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Luo Q, Yang X, Hang J, Fan X, Luo Z, Gu Z, Ou C. Influence of natural ventilation design on the dispersion of pathogen-laden droplets in a coach bus. Sci Total Environ 2023; 885:163827. [PMID: 37121320 PMCID: PMC10147445 DOI: 10.1016/j.scitotenv.2023.163827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 04/19/2023] [Accepted: 04/25/2023] [Indexed: 05/04/2023]
Abstract
Natural ventilation is an energy-efficient design approach to reduce infection risk (IR), but its optimized design in a coach bus environment is less studied. Based on a COVID-19 outbreak in a bus in Hunan, China, the indoor-outdoor coupled CFD modeling approach is adopted to comprehensively explore how optimized bus natural ventilation (e.g., opening/closing status of front/middle/rear windows (FW/MW/RW)) and ceiling wind catcher (WCH) affect the dispersion of pathogen-laden droplets (tracer gas, 5 μm, 50 μm) and IR. Other key influential factors including bus speed, infector's location, and ambient temperature (Tref) are also considered. Buses have unique natural ventilation airflow patterns: from bus rear to front, and air change rate per hour (ACH) increases linearly with bus speed. When driving at 60 km/h, ACH is only 6.14 h-1 and intake fractions of tracer gas (IFg) and 5 μm droplets (IFd) are up to 3372 ppm and 1394 ppm with ventilation through leakages on skylights and no windows open. When FW and RW are both open, ACH increases by 43.5 times to 267.50 h-1, and IFg and IFd drop rapidly by 1-2 orders of magnitude compared to when no windows are open. Utilizing a wind catcher and opening front windows significantly increases ACH (up to 8.8 times) and reduces IF (5-30 times) compared to only opening front windows. When the infector locates at the bus front with FW open, IFg and IFd of all passengers are <10 ppm. More droplets suspend and further spread in a higher Tref environment. It is recommended to open two pairs of windows or open front windows and utilize the wind catcher to reduce IR in coach buses.
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Affiliation(s)
- Qiqi Luo
- School of Atmospheric Sciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, PR China; Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai 519000, PR China
| | - Xia Yang
- Guangdong Province Engineering Laboratory for Air Pollution Control, Guangzhou, PR China
| | - Jian Hang
- School of Atmospheric Sciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, PR China; Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai 519000, PR China
| | - Xiaodan Fan
- School of Atmospheric Sciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, PR China; Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai 519000, PR China
| | - Zhiwen Luo
- Welsh School of Architecture, Cardiff University, UK
| | - Zhongli Gu
- Guangdong Fans-tech Agro Co., Ltd., PR China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, PR China; Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai 519000, PR China.
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Ou C, Hang J, Hua J, Li Y, Deng Q, Zhao B, Ling H. Particle Deposition in Large-Scale Human Tracheobronchial Airways Predicted by Single-Path Modelling. Int J Environ Res Public Health 2023; 20:4583. [PMID: 36901592 PMCID: PMC10002109 DOI: 10.3390/ijerph20054583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 02/22/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
The health effects of particles are directly related to their deposition patterns (deposition site and amount) in human airways. However, estimating the particle trajectory in a large-scale human lung airway model is still a challenge. In this work, a truncated single-path, large-scale human airway model (G3-G10) with a stochastically coupled boundary method were employed to investigate the particle trajectory and the roles of their deposition mechanisms. The deposition patterns of particles with diameters (dp) of 1-10 μm are investigated under various inlet Reynolds numbers (Re = 100-2000). Inertial impaction, gravitational sedimentation, and combined mechanism were considered. With the increasing airway generations, the deposition of smaller particles (dp < 4 μm) increased due to gravitational sedimentation, while that of larger particles decreased due to inertial impaction. The obtained formulas of Stokes number and Re can predict the deposition efficiency due to the combined mechanism in the present model, and the prediction can be used to assess the dose-effect of atmospheric aerosols on the human body. Diseases in deeper generations are mainly attributed to the deposition of smaller particles under lower inhalation rates, while diseases at the proximal generations mainly result from the deposition of larger particles under higher inhalation rates.
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Affiliation(s)
- Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Jian Hang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Jiajia Hua
- China Meteorological Administration Xiong’an Atmospheric Boundary Layer Key Laboratory, Baoding 071800, China
| | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Qihong Deng
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Bo Zhao
- China Meteorological Administration Xiong’an Atmospheric Boundary Layer Key Laboratory, Baoding 071800, China
| | - Hong Ling
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
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Malik M, Ou C, Curry M, Novack V, Weinstein J, Ahmed M, Sarwar A. Abstract No. 232 Evaluating HCC Patient Experiences to Identify Factors Associated with Underutilization of HCC Treatment in the US: A SEER-CAHPS Analysis. J Vasc Interv Radiol 2023. [DOI: 10.1016/j.jvir.2022.12.293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
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Yu LC, Hu C, Yang W, Ou C, Jan H, Jan. Prognostic significance of multifocal upper tumors with presence of high inflammation status in upper tract urothelial carcinoma following radical nephrouretectomy. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00958-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Luo Q, Ou C, Hang J, Luo Z, Yang H, Yang X, Zhang X, Li Y, Fan X. Role of pathogen-laden expiratory droplet dispersion and natural ventilation explaining a COVID-19 outbreak in a coach bus. Build Environ 2022; 220:109160. [PMID: 35615259 PMCID: PMC9122785 DOI: 10.1016/j.buildenv.2022.109160] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 04/28/2022] [Accepted: 04/30/2022] [Indexed: 05/30/2023]
Abstract
The influencing mechanism of droplet transmissions inside crowded and poorly ventilated buses on infection risks of respiratory diseases is still unclear. Based on experiments of one-infecting-seven COVID-19 outbreak with an index patient at bus rear, we conducted CFD simulations to investigate integrated effects of initial droplet diameters(tracer gas, 5 μm, 50 μm and 100 μm), natural air change rates per hour(ACH = 0.62, 2.27 and 5.66 h-1 related to bus speeds) and relative humidity(RH = 35% and 95%) on pathogen-laden droplet dispersion and infection risks. Outdoor pressure difference around bus surfaces introduces natural ventilation airflow entering from bus-rear skylight and leaving from the front one. When ACH = 0.62 h-1(idling state), the 30-min-exposure infection risk(TIR) of tracer gas is 15.3%(bus rear) - 11.1%(bus front), and decreases to 3.1%(bus rear)-1.3%(bus front) under ACH = 5.66 h-1(high bus speed).The TIR of large droplets(i.e., 100 μm/50 μm) is almost independent of ACH, with a peak value(∼3.1%) near the index patient, because over 99.5%/97.0% of droplets deposit locally due to gravity. Moreover, 5 μm droplets can disperse further with the increasing ventilation. However, TIR for 5 μm droplets at ACH = 5.66 h-1 stays relatively small for rear passengers(maximum 0.4%), and is even smaller in the bus middle and front(<0.1%). This study verifies that differing from general rooms, most 5 μm droplets deposit on the route through the long-and-narrow bus space with large-area surfaces(L∼11.4 m). Therefore, tracer gas can only simulate fine droplet with little deposition but cannot replace 5-100 μm droplet dispersion in coach buses.
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Affiliation(s)
- Qiqi Luo
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
| | - Jian Hang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
| | - Zhiwen Luo
- School of the Built Environment, University of Reading, Reading, UK
| | - Hongyu Yang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
| | - Xia Yang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
| | - Xuelin Zhang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
| | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Xiaodan Fan
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai, 519000, China
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Huang J, Hao T, Liu X, Jones P, Ou C, Liang W, Liu F. Airborne transmission of the Delta variant of SARS-CoV-2 in an auditorium. Build Environ 2022; 219:109212. [PMID: 35645452 PMCID: PMC9128309 DOI: 10.1016/j.buildenv.2022.109212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/23/2022] [Accepted: 05/16/2022] [Indexed: 05/30/2023]
Abstract
The Delta variant of SARS-CoV-2 has inflicted heavy burdens on healthcare systems globally, although direct evidence on the quantity of exhaled viral shedding from Delta cases is lacking. The literature remains inconclusive on whether existing public health guidance, based on earlier evidence of COVID-19, should respond differently to more infectious viral strains. This paper describes a study on an outbreak of the Delta variant of COVID-19 in an auditorium, where one person contracted the virus from three asymptomatic index cases sitting in a different row. Field inspections were conducted on the configuration of seating, building and ventilation systems. Numerical simulation was conducted to retrospectively assess the exhaled viral emission, decay, airborne dispersion, with a modified Wells-Riley equation used to calculate the inhalation exposure and disease infection risks at the seat level. Results support the airborne disease transmission. The viral emission rate for Delta cases was estimated at 31 quanta per hour, 30 times higher than those of the original variant. The high quantity of viral plume exhaled by delta cases can create a high risk zone nearby, which, for a mixing ventilation system, cannot be easily mitigated by raising mixing rates or introducing fresh air supply. Such risks can be reduced by wearing an N95 respirator, less so for social distancing. A displacement ventilation system, through which the air is supplied at the floor and returned from the ceiling, can reduce risks compared with a mixing system. The study has implications for ventilation guidelines and hygiene practices in light of more infectious viral strains of COVID-19.
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Affiliation(s)
- Jianxiang Huang
- Department of Urban Planning and Design, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China
- The University of Hong Kong Shenzhen Institute of Research and Innovation, 5/F, Key Laboratory Platform Building, Shenzhen Virtual University Park, No.6, Yuexing 2nd Rd, Nanshan, Shenzhen, 518057, China
- Sustainable High Density Cities Lab, HKUrban Lab, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China
| | - Tongping Hao
- Department of Urban Planning and Design, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China
- The University of Hong Kong Shenzhen Institute of Research and Innovation, 5/F, Key Laboratory Platform Building, Shenzhen Virtual University Park, No.6, Yuexing 2nd Rd, Nanshan, Shenzhen, 518057, China
- Sustainable High Density Cities Lab, HKUrban Lab, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China
| | - Xiao Liu
- School of Architecture, South China University of Technology, Guangzhou, 510641, China
- Sustainable High Density Cities Lab, HKUrban Lab, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China
| | - Phil Jones
- Welsh School of Architecture, Cardiff University, King Edward VII Avenue, Cardiff, United Kingdom
| | - Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Weihui Liang
- School of Architecture and Urban Planning, Nanjing University, Nanjing, 210093, China
| | - Fuqiang Liu
- Office of Emergency Response to Public Health Emergencies, Hunan Provincial Center for Disease Control and Prevention, No. 450, Section 1, Furong Middle Road, Kaifu District, Changsha City, Hunan Province, China
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Cheng P, Luo K, Xiao S, Yang H, Hang J, Ou C, Cowling BJ, Yen HL, Hui DS, Hu S, Li Y. Predominant airborne transmission and insignificant fomite transmission of SARS-CoV-2 in a two-bus COVID-19 outbreak originating from the same pre-symptomatic index case. J Hazard Mater 2022; 425:128051. [PMID: 34910996 PMCID: PMC8656245 DOI: 10.1016/j.jhazmat.2021.128051] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 05/22/2023]
Abstract
The number of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to increase worldwide, but despite extensive research, there remains significant uncertainty about the predominant routes of SARS-CoV-2 transmission. We conducted a mechanistic modeling and calculated the exposure dose and infection risk of each passenger in a two-bus COVID-19 outbreak in Hunan province, China. This outbreak originated from a single pre-symptomatic index case. Some human behavioral data related to exposure including boarding and alighting time of some passengers and seating position and mask wearing of all passengers were obtained from the available closed-circuit television images/clips and/or questionnaire survey. Least-squares fitting was performed to explore the effect of effective viral load on transmission risk, and the most likely quanta generation rate was also estimated. This study reveals the leading role of airborne SARS-CoV-2 transmission and negligible role of fomite transmission in a poorly ventilated indoor environment, highlighting the need for more targeted interventions in such environments. The quanta generation rate of the index case differed by a factor of 1.8 on the two buses and transmission occurred in the afternoon of the same day, indicating a time-varying effective viral load within a short period of five hours.
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Affiliation(s)
- Pan Cheng
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Kaiwei Luo
- Hunan Provincial Center for Disease Control and Prevention, Changsha, China
| | - Shenglan Xiao
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China; School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Hongyu Yang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Jian Hang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | | | - Hui-Ling Yen
- School of Public Health, The University of Hong Kong, Hong Kong, China
| | - David Sc Hui
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China
| | - Shixiong Hu
- Hunan Provincial Center for Disease Control and Prevention, Changsha, China
| | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China; School of Public Health, The University of Hong Kong, Hong Kong, China.
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Ou C, Hu S, Luo K, Yang H, Hang J, Cheng P, Hai Z, Xiao S, Qian H, Xiao S, Jing X, Xie Z, Ling H, Liu L, Gao L, Deng Q, Cowling BJ, Li Y. Insufficient ventilation led to a probable long-range airborne transmission of SARS-CoV-2 on two buses. Build Environ 2022; 207:108414. [PMID: 34629689 PMCID: PMC8487323 DOI: 10.1016/j.buildenv.2021.108414] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 05/02/2023]
Abstract
Uncertainty remains on the threshold of ventilation rate in airborne transmission of SARS-CoV-2. We analyzed a COVID-19 outbreak in January 2020 in Hunan Province, China, involving an infected 24-year-old man, Mr. X, taking two subsequent buses, B1 and B2, in the same afternoon. We investigated the possibility of airborne transmission and the ventilation conditions for its occurrence. The ventilation rates on the buses were measured using a tracer-concentration decay method with the original driver on the original route. We measured and calculated the spread of the exhaled virus-laden droplet tracer from the suspected index case. Ten additional passengers were found to be infected, with seven of them (including one asymptomatic) on B1 and two on B2 when Mr. X was present, and one passenger infected on the subsequent B1 trip. B1 and B2 had time-averaged ventilation rates of approximately 1.7 and 3.2 L/s per person, respectively. The difference in ventilation rates and exposure time could explain why B1 had a higher attack rate than B2. Airborne transmission due to poor ventilation below 3.2 L/s played a role in this two-bus outbreak of COVID-19.
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Affiliation(s)
- Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Shixiong Hu
- Hunan Provincial Center for Disease Control and Prevention, Changsha, China
| | - Kaiwei Luo
- Hunan Provincial Center for Disease Control and Prevention, Changsha, China
| | - Hongyu Yang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Jian Hang
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Pan Cheng
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Zheng Hai
- Shaodong County Center for Disease Control and Prevention, Shaodong, China
| | - Shanliang Xiao
- Shaoyang City Center for Disease Control and Prevention, Shaoyang, China
| | - Hua Qian
- School of Energy and Environment, Southeast University, Nanjing, China
| | - Shenglan Xiao
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Xinping Jing
- Shaodong County Center for Disease Control and Prevention, Shaodong, China
| | - Zhengshen Xie
- Shaodong County Center for Disease Control and Prevention, Shaodong, China
| | - Hong Ling
- School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Li Liu
- School of Architecture, Tsinghua University, Beijing, China
| | - Lidong Gao
- Hunan Provincial Center for Disease Control and Prevention, Changsha, China
| | - Qihong Deng
- XiangYa School of Public Health, Central South University, Changsha, China
| | | | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
- School of Public Health, The University of Hong Kong, Hong Kong, China
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Ng Y, Nguyen E, Bei B, Hamilton G, Rajaratnam S, Ou C, Mansfield D. P103 Impact of the COVID-19 pandemic on the sleep of patients of a multidisciplinary sleep clinic. SLEEP Advances 2021. [PMCID: PMC8500137 DOI: 10.1093/sleepadvances/zpab014.147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Introduction
This study aimed to assess the impact of the COVID-19 pandemic on the sleep of adult patients of a multidisciplinary sleep clinic.
Methods
Patients were invited to complete online surveys: Survey 1 in October 2020 (increased COVID-19 restrictions) followed by Survey 2 in February 2021 (after easing of restrictions for a COVIDSafe summer).
Results
Of the 746 patients invited to participate, 73 completed and 8 partially returned Survey 1 (mean age 50.1 years, range 21–83 years, 58% female). Subsequently, 46 completed and 5 partially answered Survey 2. In Survey 1, 22/74 (29.7%) reported reduced sleep quantity and 31/75 (41.3%) indicated worse sleep quality compared with prior to the pandemic. In Survey 2, 33/46 (71.7%) described unchanged sleep quantity whilst 5/46 (10.9%) reported increased sleep quantity since easing COVID-19 restrictions. 36/46 (78.3%) indicated unchanged sleep quality whereas 5/46 (10.9%) described improved sleep quality since easing restrictions. However, 9/46 (19.6%) reported that their sleep remained worse compared with pre-pandemic. For patients who completed both surveys, there was no significant change in Insomnia Severity Index scores (Survey 1 mean 13.6, Survey 2 mean 12.9, mean difference -0.67 [95%CI -2.02, 0.68], p=0.32) or PROMIS Sleep-Related Impairment 8a T-scores (Survey 1 mean 59.0, Survey 2 mean 59.5, mean difference 0.44 [95%CI -1.55, 2.42], p=0.66).
Discussion
The COVID-19 pandemic has negatively affected the sleep of 44% of patients. Following easing of restrictions, symptoms of insomnia and sleep-related impairment did not change significantly, and 19.6% reported that their sleep was not back to their pre-pandemic baseline.
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Affiliation(s)
- Y Ng
- Monash University, Notting Hill, Australia
- Monash Lung, Sleep, Allergy and Immunology, Monash Health, Clayton, Australia
| | - E Nguyen
- Monash University, Notting Hill, Australia
| | - B Bei
- Monash University, Notting Hill, Australia
| | - G Hamilton
- Monash University, Notting Hill, Australia
- Monash Lung, Sleep, Allergy and Immunology, Monash Health, Clayton, Australia
| | | | - C Ou
- Monash University, Notting Hill, Australia
| | - D Mansfield
- Monash University, Notting Hill, Australia
- Monash Lung, Sleep, Allergy and Immunology, Monash Health, Clayton, Australia
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Zhang N, Chen X, Jia W, Jin T, Xiao S, Chen W, Hang J, Ou C, Lei H, Qian H, Su B, Li J, Liu D, Zhang W, Xue P, Liu J, Weschler LB, Xie J, Li Y, Kang M. Evidence for lack of transmission by close contact and surface touch in a restaurant outbreak of COVID-19. J Infect 2021; 83:207-216. [PMID: 34062182 PMCID: PMC8164346 DOI: 10.1016/j.jinf.2021.05.030] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/23/2021] [Accepted: 05/26/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND Coronavirus disease 2019 (COVID-19) is primarily a respiratory disease that has become a global pandemic. Close contact plays an important role in infection spread, while fomite may also be a possible transmission route. Research during the COVID-19 pandemic has identified long-range airborne transmission as one of the important transmission routes although lack solid evidence. METHODS We examined video data related to a restaurant associated COVID-19 outbreak in Guangzhou. We observed more than 40,000 surface touches and 13,000 episodes of close contacts in the restaurant during the entire lunch duration. These data allowed us to analyse infection risk via both the fomite and close contact routes. RESULTS There is no significant correlation between the infection risk via both fomite and close contact routes among those who were not family members of the index case. We can thus rule out virus transmission via fomite contact and interpersonal close contact routes in the Guangzhou restaurant outbreak. The absence of a fomite route agrees with the COVID-19 literature. CONCLUSIONS These results provide indirect evidence for the long-range airborne route dominating SARS-CoV-2 transmission in the restaurant. We note that the restaurant was poorly ventilated, allowing for increasing airborne SARS-CoV-2 concentration.
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Affiliation(s)
- Nan Zhang
- Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology, Beijing University of Technology, Beijing, China
| | - Xuguang Chen
- Guangdong Provincial Center for Disease Control and Prevention, Guangdong province, China
| | - Wei Jia
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Tianyi Jin
- Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology, Beijing University of Technology, Beijing, China
| | - Shenglan Xiao
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangzhou, China
| | - Wenzhao Chen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Jian Hang
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China
| | - Hao Lei
- School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hua Qian
- School of Energy and Environment, Southeast University, Nanjing, China
| | - Boni Su
- China Electric Power Planning & Engineering Institute, Beijing, China
| | - Jiansen Li
- Guangdong Provincial Center for Disease Control and Prevention, Guangdong province, China
| | - Dongmei Liu
- Fogang County Center for Disease Control and Prevention, Guangdong, China
| | - Weirong Zhang
- Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology, Beijing University of Technology, Beijing, China
| | - Peng Xue
- Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology, Beijing University of Technology, Beijing, China
| | - Jiaping Liu
- Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology, Beijing University of Technology, Beijing, China
| | | | - Jingchao Xie
- Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology, Beijing University of Technology, Beijing, China.
| | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong; School of Public Health, The University of Hong Kong, Pokfulam Road, Hong Kong.
| | - Min Kang
- Guangdong Provincial Center for Disease Control and Prevention, Guangdong province, China; School of Public Health, Southern Medical University, Guangzhou, China.
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11
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Yang X, Yang H, Ou C, Luo Z, Hang J. Airborne transmission of pathogen-laden expiratory droplets in open outdoor space. Sci Total Environ 2021; 773:145537. [PMID: 33582331 DOI: 10.1016/j.scitotenv.2021.145537] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 01/27/2021] [Accepted: 01/27/2021] [Indexed: 06/12/2023]
Abstract
Virus-laden droplets dispersion may induce transmissions of respiratory infectious diseases. Existing research mainly focuses on indoor droplet dispersion, but the mechanism of its dispersion and exposure in outdoor environment is unclear. By conducting CFD simulations, this paper investigates the evaporation and transport of solid-liquid droplets in an open outdoor environment. Droplet initial sizes (dp = 10 μm, 50 μm, 100 μm), background relative humidity (RH = 35%, 95%), background wind speed (Uref = 3 m/s, 0.2 m/s) and social distances between two people (D = 0.5 m, 1 m, 1.5 m, 3 m, 5 m) are investigated. Results show that thermal body plume is destroyed when the background wind speed is 3 m/s (Froude number Fr ~ 10). The inhalation fraction (IF) of susceptible person decreases exponentially when the social distance (D) increases from 0.5 m to 5 m. The exponential decay rate of inhalation fraction (b) ranges between 0.93 and 1.06 (IF=IF0e-b(D-0.5)) determined by the droplet initial diameter and relative humidity. Under weak background wind (Uref = 0.2 m/s, Fr ~ 0.01), the upward thermal body plume significantly influences droplet dispersion, which is similar with that in indoor space. Droplets in the initial sizes of 10 μm and 50 μm disperse upwards while most of 100 μm droplets fall down to the ground due to larger gravity force. Interestingly, the deposition fraction on susceptible person is ten times higher at Uref = 3 m/s than that at Uref = 0.2 m/s. Thus, a high outdoor wind speed does not necessarily lead to a smaller exposure risk if the susceptible person locating at the downwind region of the infected person, and people in outdoors are suggested to not only keep distance of greater than 1.5 m from each other but also stand with considerable angles from the prevailing wind direction.
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Affiliation(s)
- Xia Yang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, 510275 Guangzhou, China
| | - Hongyu Yang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, 510275 Guangzhou, China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, 510275 Guangzhou, China; State Key Laboratory of Green Building in Western China, Xian University of Architecture & Technology, 710055 Xi'an, China
| | - Zhiwen Luo
- School of the Built Environment, University of Reading, Reading, UK.
| | - Jian Hang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, 510275 Guangzhou, China.
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12
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Lam CKC, Gao Y, Yang H, Chen T, Zhang Y, Ou C, Hang J. Interactive effect between long-term and short-term thermal history on outdoor thermal comfort: Comparison between Guangzhou, Zhuhai and Melbourne. Sci Total Environ 2021; 760:144141. [PMID: 33341630 DOI: 10.1016/j.scitotenv.2020.144141] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 11/09/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Thermal history can influence human thermal comfort through physiological (short-term) and psychological (long-term) aspects. However, the nature of the interaction between long-term and short-term thermal history is unclear. To investigate the interactive effects of long-term and short-term thermal history on outdoor thermal comfort, we conducted summer thermal comfort surveys in Melbourne (n = 3293, January-February 2014), Guangzhou, and Zhuhai (n = 4304, September 2018). The mean thermal sensation of residents of Guangzhou was higher than that of Melbourne and Zhuhai residents under a similar Universal Thermal Climate Index (UTCI) range. The preferred UTCI was the highest for Melbourne residents (19.62 °C). When UTCI was 25.6-38.4 °C, respondents' mean thermal sensation from Köppen climate zones A, B, and C was significantly higher in Guangzhou than those of Zhuhai and Melbourne. A three-way ANOVA test revealed that peoples' thermal sensations depended on a significant interaction among UTCI thermal stress levels, climate zones, and prior exposure environment. The prior exposure environment could affect the difference in thermal perception between climate zones. However, there was no significant interaction between climate zones and activity engaged in before taking the survey on thermal sensation. The difference in the thermal perception of various climate zones diminished under universally uncomfortable conditions for specific prior exposure environments and activities. The socio-ecological system model, environmental perception theory, climatocultural adaptation, and alliesthesia are useful for understanding the interactive effect of long- and short-term thermal history on outdoor thermal comfort. By revealing how people adapt to different climatic environments, our results can help ensure that people with diverse climatic backgrounds can experience thermal comfort outdoors.
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Affiliation(s)
- Cho Kwong Charlie Lam
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, Guangzhou, China
| | - Yanping Gao
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
| | - Hongyu Yang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
| | - Taihan Chen
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
| | - Yong Zhang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, Guangzhou, China
| | - Jian Hang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Guangdong Provincial Field Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, Guangzhou, China.
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13
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Yang X, Ou C, Yang H, Liu L, Song T, Kang M, Lin H, Hang J. Transmission of pathogen-laden expiratory droplets in a coach bus. J Hazard Mater 2020; 397:122609. [PMID: 32361671 PMCID: PMC7152903 DOI: 10.1016/j.jhazmat.2020.122609] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 03/25/2020] [Accepted: 03/27/2020] [Indexed: 05/04/2023]
Abstract
Droplet dispersion carrying viruses/bacteria in enclosed/crowded buses may induce transmissions of respiratory infectious diseases, but the influencing mechanisms have been rarely investigated. By conducting high-resolution CFD simulations, this paper investigates the evaporation and transport of solid-liquid mixed droplets (initial diameter 10 μm and 50 μm, solid to liquid ratio is 1:9) exhaled in a coach bus with 14 thermal manikins. Five air-conditioning supply directions and ambient relative humidity (RH = 35 % and 95 %) are considered. Results show that ventilation effectiveness, RH and initial droplet size significantly influence droplet transmissions in coach bus. 50 μm droplets tend to evaporate completely within 1.8 s and 7 s as RH = 35 % and 95 % respectively, while 0.2 s or less for 10 μm droplets. Thus 10 μm droplets diffuse farther with wider range than 50 μm droplets which tend to deposit more on surfaces. Droplet dispersion pattern differs due to various interactions of gravity, ventilation flows and the upward thermal body plume. The fractions of droplets suspended in air, deposited on wall surfaces are quantified. This study implies high RH, backward supply direction and passengers sitting at nonadjacent seats can effectively reduce infection risk of droplet transmission in buses. Besides taking masks, regular cleaning is also recommended since 85 %-100 % of droplets deposit on object surfaces.
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Affiliation(s)
- Xia Yang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China
| | - Cuiyun Ou
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China
| | - Hongyu Yang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China
| | - Li Liu
- Department of Building Science, School of Architecture, Tsinghua University, Beijing, 100084, PR China
| | - Tie Song
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, PR China
| | - Min Kang
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, PR China
| | - Hualiang Lin
- Department of Epidemiology, School of Public Health, Sun Yat-sen University Guangzhou, PR China
| | - Jian Hang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, PR China.
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14
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Chen G, Wang D, Wang Q, Li Y, Wang X, Hang J, Gao P, Ou C, Wang K. Scaled outdoor experimental studies of urban thermal environment in street canyon models with various aspect ratios and thermal storage. Sci Total Environ 2020; 726:138147. [PMID: 32305749 DOI: 10.1016/j.scitotenv.2020.138147] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/18/2020] [Accepted: 03/21/2020] [Indexed: 06/11/2023]
Abstract
Street aspect ratios and urban thermal storage largely determine the thermal environment in cities. By performing scaled outdoor measurements in summer of 2017 in Guangzhou, China, we investigate these impacts on spatial/temporal characteristics of urban thermal environment which are still unclear so far. Two types of street canyon models are investigated, i.e. the 'hollow' model resembling hollow concrete buildings and the 'sand' model consisting of buildings filled with sand attaining much greater thermal storage. For each model, three street aspect ratios (building height/street width, H/W = 1, 2, 3; H = 1.2 m) are considered. The diurnal variations of air-wall surface temperatures are observed and their characteristics are quantified for various cases. The daily average temperature and daily temperature range (DTR) of wall temperature vary significantly with different aspect ratios and thermal storage. During the daytime, wider street canyon (H/W = 1) with less shading area experiences higher temperature than narrower ones (H/W = 2, 3) as more solar radiation received by wall surfaces. At night, wider street canyon cools down quicker due to stronger upward longwave radiation and night ventilation. For hollow models, H/W = 1 attains DTR of 12.1 °C, which is 1.2 and 2.1 °C larger than that of H/W = 2, 3. Moreover, the sand models experience smaller DTR and a less changing rate of wall temperature than hollow models because larger thermal storage absorbs more heat in the daytime and releases more at night. DTR of hollow models with H/W = 1, 2, 3 is 4.5, 4.6 and 3.8 °C greater than sand models respectively. For both hollow and sand models, wider streets experience a little higher daily average temperature (0.3-0.6 °C) than narrower ones. Our study provides direct evidence in how man-made urban structures influence urban climate and also suggests the possibility to control outdoor thermal environment by optimize urban morphology and thermal storage.
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Affiliation(s)
- Guanwen Chen
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China 510275
| | - Dongyang Wang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China 510275
| | - Qun Wang
- Department of Mechanical Engineering, the University of Hong Kong, Pokfulam Road, Hong Kong
| | - Yuguo Li
- Department of Mechanical Engineering, the University of Hong Kong, Pokfulam Road, Hong Kong
| | - Xuemei Wang
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, PR China
| | - Jian Hang
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China 510275; Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai), Zhuhai, China; Key Laboratory of Tropical Atmosphere-Ocean System (Sun Yat-sen University), Ministry of Education, Zhuhai (519000), China.
| | - Peng Gao
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China 510275
| | - Cuiyun Ou
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, PR China 510275
| | - Kai Wang
- Department of Mechanical Engineering, the University of Hong Kong, Pokfulam Road, Hong Kong.
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15
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Zhang Y, Song X, Zhang P, Gao H, Ou C, Kong X. Production of activated carbons from four wastes via one-step activation and their applications in Pb 2+ adsorption: Insight of ash content. Chemosphere 2020; 245:125587. [PMID: 31864062 DOI: 10.1016/j.chemosphere.2019.125587] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 12/03/2019] [Accepted: 12/08/2019] [Indexed: 06/10/2023]
Abstract
Natural biomass is a renewable source for precursors of porous carbon. Four agriculture wastes of corn cob (CC), wheat bran (WB), rice husk (RH), and soybean shell (SS) were applied to produce activated carbons (ACs) via one-step activation by sodium hydroxide. The effects of ash contents and NaOH dosage ratio (1-5) on surface area for ACs were investigated. Owing to ash etching, the high ash precursor (like RH) exhibited less alkali consumption and larger surface area than low ash one (like CC). All four ACs expressed developed pore structure and outstanding surface area of ∼2500 m2g-1. During adsorption of lead ions in simulated wastewater, RH-based AC revealed superior capture capacity of 492 ± 15 mgg-1. One-step activation had the potential to deliver savings around 1/3 of energy consumption, enabling the cost performance of high ash RH-based AC reaching 194 ± 12 g Pb2+$-1, 76% larger than low ash CC-based AC. High ash biomass is a promising candidate to obtain eco-friendly carbon products.
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Affiliation(s)
- Ying Zhang
- Key Laboratory for Mineral Materials and Application of Hunan Province, School of Mineral Processing and Bioengineering, Central South University, Changsha, 410083, China
| | - Xiaolan Song
- Key Laboratory for Mineral Materials and Application of Hunan Province, School of Mineral Processing and Bioengineering, Central South University, Changsha, 410083, China.
| | - Pu Zhang
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, United States
| | - Hongpeng Gao
- Department of NanoEngineering, University of California San Diego, La Jolla, CA, 92093, United States
| | - Cuiyun Ou
- School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, 510275, China; Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Zhuhai, China
| | - Xiaodong Kong
- Key Laboratory for Mineral Materials and Application of Hunan Province, School of Mineral Processing and Bioengineering, Central South University, Changsha, 410083, China
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16
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Zhang W, Xiang Y, Lu C, Ou C, Deng Q. Numerical modeling of particle deposition in the conducting airways of asthmatic children. Med Eng Phys 2019; 76:40-46. [PMID: 31879223 DOI: 10.1016/j.medengphy.2019.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 09/30/2019] [Accepted: 10/20/2019] [Indexed: 02/05/2023]
Abstract
Mounting evidence has linked long- and short-term exposure to particulate air pollution with the incidence and exacerbation of asthma in children, but the biological pathogenesis is unclear. We examined the deposition of particles in the airways of asthmatic children. A planar and symmetric model of airways for 4-year-old asthmatic children was considered. Airflow and particle deposition in the upper (G3-G6) and lower (G9-G12) conducting airways were numerically investigated using computation fluid dynamics (CFD) method. We considered the manifestation of moderate (30% reduction in airway diameter) and severe (60% reduction) asthma. Micron particles (1-10 µm) were considered. We found that particle deposition in the asthmatic children was significantly higher than that in healthy children. The deposition efficiency increased slowly with particle size for healthy children, but increased rapidly for asthmatic children, such that smaller particles could be deposited in the conducting airways of asthmatics. For healthy children, particles were deposited by inertial impaction and gravitational sedimentation respectively in the upper and lower airways, but deposited by inertial impaction in asthmatic children. The severity of the asthma increased the particle deposition in the airways. Our study indicated that asthmatic children were more susceptible to the effect of particulate air pollution. The constricted airways increased the particle deposition by inertial impaction, which may be the biological pathogenesis that causes the hospitalization of asthma in children. Avoiding exposure during air pollution events will be an effective measure to reduce the asthma attack.
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Affiliation(s)
- Wenwen Zhang
- School of Energy Science and Engineering, Central South University, Changsha 410083, China
| | - Yuguang Xiang
- School of Energy Science and Engineering, Central South University, Changsha 410083, China
| | - Chan Lu
- School of Energy Science and Engineering, Central South University, Changsha 410083, China; XiangYa School of Public Health, Central South University, Changsha 410078, China
| | - Cuiyun Ou
- School of Energy Science and Engineering, Central South University, Changsha 410083, China; School of Atmospheric Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Qihong Deng
- School of Energy Science and Engineering, Central South University, Changsha 410083, China; XiangYa School of Public Health, Central South University, Changsha 410078, China; School of Public Health, Zhengzhou University, Zhengzhou 450001, China; School of School of Architecture and Art, Central South University, Changsha 410083, China.
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17
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Gao P, Hu J, Song J, Chen X, Ou C, Wang H, Sha C, Hang J, Xing B. Inhalation bioaccessibility of polycyclic aromatic hydrocarbons in heavy PM 2.5 pollution days: Implications for public health risk assessment in northern China. Environ Pollut 2019; 255:113296. [PMID: 31600706 DOI: 10.1016/j.envpol.2019.113296] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 06/10/2023]
Abstract
Airborne (PM2.5) with aerodynamic diameter ≤ 2.5 μm was collected from 4 types of cities in northeast China during the heating period. The objectives of this study were to assess the concentrations variation of PM2.5-bound 12 carcinogenic polycyclic aromatic hydrocarbons (PAH12), to study the influence of simulated lung fluids on bioaccessibility of PAH12 and to estimate the variation of lifetime excess cancer risk to the residents, artificial lysosomal fluid (ALF) and Gamble's solution were used. The number of lifetime excess cancer cases (determined by California Environmental Protection Agency method) as a result of PAH12 exposure (total concentration) was 4.00-430 (provincial central cities), 24.0-261 (energy-mining cities), 17.0-109 (forested city), and 20.0-69.0 (agricultural city) per million people, which relatively corresponded to a 92.2% and 96.2%, 92.6% and 97.3%, 92.2% and 94.2%, and 86.5% and 92.6% decrease after considering bioaccessibility following 24-h of Gamble's solution and ALF extraction, respectively. Phenanthrene (Phe), dibenz[a,h]anthracene (DahA) and benzo[a]pyrene (BaP) were found to be the most bioaccessible types of PAH12 after the Gamble's solution and ALF extraction in the PM2.5 samples from all the studied cities. Based on the point-estimate approach, short-term predictions of pulmonary toxicity caused by potential inhalation of airborne PM into the pulmonary system might be overestimated if bioaccessibility of PM2.5-bound PAH12 is not fully evaluated.
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Affiliation(s)
- Peng Gao
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Jian Hu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, PR China
| | - Jie Song
- School of Geography and Planning, Sun Yat-sen University, Guangzhou, PR China
| | - Xin Chen
- China National Environmental Monitoring Centre, Beijing, PR China
| | - Cuiyun Ou
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Hao Wang
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Chenyuan Sha
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Jian Hang
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, PR China.
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, USA
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18
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Mao AY, Chen MJ, Yang C, Ou C, Ye XQ, Qin QH, Mo M, Wei CY. [Comparison of modeling effects of two different 7, 12-dimethylbenz[a] anthracene induced breast cancer models in tree shrew]. Zhonghua Zhong Liu Za Zhi 2019; 41:346-350. [PMID: 31137167 DOI: 10.3760/cma.j.issn.0253-3766.2019.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the feasibility of 7, 12-dimethylbenz[a] anthracene (DMBA) induced tree shrew breast cancer model, and compare the effects of two administration modes by gavage and mammary gland injection. Methods: A total of 40 tree shrews were randomly divided into two groups (20 animals per group): DMBA gavage group and mammary gland injection group. DMBA was dissolved in edible vegetable oil. For gavage group, tree shrews were administered with DMBA solutions (15 mg/kg) by gavage once a day. For mammary gland injection group, DMBA solution (10 mg/kg) was injected into the mammary fat pad of tree shrews, and the injection was performed for a total of 3 times. From the first administration of DMBA, medroxyprogesterone acetate (MPA, 100 mg/kg) was intramuscularly injected into the muscles of the lateral thighs of tree shrews at the same time, for a total of 5 times. The tumorigenesis and survival of tree shrews were monitored. The tumor histological morphology was observed by HE staining. The expression of estrogen receptor (ER), progesterone receptor (PR), cytokeratin5/6 (CK5/6) and human epidermal factor receptor-2 (HER-2) was detected by immunohistochemical staining. Results: In the gavage group, there were 10 deaths, and 4 tree shrews developed mammary tumors with 20.0% (4/20) tumor formation rate. The success rate of mammary cancer modeling was 10.0% (2/20), and the tumor formation time was 197.3±15.1 days. In the mammary gland injection group, there were 8 tree shrews died, and 9 tree shrews formed tumors with 45.0% (9/20) tumor formation rate. The success rate of mammary cancer modeling was 40.0% (8/20), and the tumor formation time was 71.8±19.0 days. There was no significant difference in mortality and tumor formation rate (P>0.05) between the two groups (all P>0.05). However, in the mammary gland injection group, the success rate of mammary cancer modeling was significantly higher than that in the gavage group (P<0.05), whereas the tumor formation time was markedly shorter than that in the gavage group (P<0.01). The pathological types in the gavage group included ductal hyperplasia, intraductal papilloma and ductal carcinoma in situ, while those in the breast injection group included intraductal papilloma and ductal carcinoma in situ. In both groups, immunohistochemical staining showed the negative expression of HER-2 but positive expression of ER, PR and CK5/6 with varying degrees. Conclusion: Both the DMBA gavage and mammary gland injection can successfully establish the tree shrew breast cancer model, and the modeling effect of mammary gland injection is better than gavage.
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Affiliation(s)
- A Y Mao
- Department of Breast Surgery, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - M J Chen
- Department of Breast Surgery, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - C Yang
- Department of Experimental Research, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - C Ou
- Department of Experimental Research, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - X Q Ye
- Department of Pathology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - Q H Qin
- Department of Breast Surgery, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - M Mo
- Department of Breast Surgery, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
| | - C Y Wei
- Department of Breast Surgery, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, China
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19
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Deng Q, Ou C, Shen YM, Xiang Y, Miao Y, Li Y. Health effects of physical activity as predicted by particle deposition in the human respiratory tract. Sci Total Environ 2019; 657:819-826. [PMID: 30677947 DOI: 10.1016/j.scitotenv.2018.12.067] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/05/2018] [Accepted: 12/05/2018] [Indexed: 05/04/2023]
Abstract
Although health benefits of physical activity are well known, the risk of physical activity in polluted air is unclear. Our objective is to investigate health effects resulting from physical activity in polluted air by looking at particle deposition in human tracheobronchial (TB) airways. Airflow and particle deposition in TB airways were investigated using a computational fluid dynamics (CFD) method. We chose three regional airways: upper (G3-G5), central (G9-G11) and lower (G14-G16). Physical activity was described by breathing rate at the mouth, for three levels of activity: sedentary (15 l/min), moderate (30 l/min) and intense (60 l/min). We found that particle deposition was strongly affected by physical activity. Particles are deposited in greater number in the lower airways (G14-G16) during sedentary activity, more in the upper airways (G3-G5) during intense activity, and uniformly in the airways during moderate activity. The difference in the deposition pattern was due to the reason that physical activity increased the airflow which increased inertial impaction. Our modeling of particle deposition in the human respiratory airways shows that there are different health effects for different activity levels: sedentary activity leads to chronic health effects, intense activity results in acute effects, and moderate activity minimizes the adverse health effects of physical activity in polluted air.
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Affiliation(s)
- Qihong Deng
- School of Energy Science and Engineering, Central South University, Changsha 410083, China; XiangYa School of Public Health, Central South University, Changsha 410078, China.
| | - Cuiyun Ou
- School of Energy Science and Engineering, Central South University, Changsha 410083, China; School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou 510275, PR China
| | - Yong-Ming Shen
- Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China
| | - Yuguang Xiang
- School of Energy Science and Engineering, Central South University, Changsha 410083, China
| | - Yufeng Miao
- School of Energy Science and Engineering, Central South University, Changsha 410083, China
| | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
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Gao P, Guo H, Zhang Z, Ou C, Hang J, Fan Q, He C, Wu B, Feng Y, Xing B. Bioaccessibility and exposure assessment of trace metals from urban airborne particulate matter (PM 10 and PM 2.5) in simulated digestive fluid. Environ Pollut 2018; 242:1669-1677. [PMID: 30077404 DOI: 10.1016/j.envpol.2018.07.109] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 07/18/2018] [Accepted: 07/23/2018] [Indexed: 05/17/2023]
Abstract
We describe a batch-extraction with simulated digestive fluid (salivary fluid, gastric fluid and intestinal fluid) to estimate the bioaccessibility of inhaled trace metals (TMs) in particulate matter less than 10 and 2.5 μm in aerodynamic diameter (PM10 and PM2.5). Concentrations of the assayed TMs (As, Cd, Cr, Ni, Mn, Cu, Zn, Sb, Hg and Pb) were determined in PM10 and PM2.5 samples by inductively coupled plasma-mass spectrometry. The TMs with the largest soluble fractions for airborne PM collected from winter and summer in saliva were Mn and Sb, respectively; in seasons this became Co in gastric fluid and Cu in intestinal fluid. Clearly, bioaccessibility is strongly dependent on particle size, the component of simulated digestive fluids (e.g., pH, digestive enzymes pepsin and trypsin), and the chemical properties of metal ions. The particle size and seasonal variation affected the inhaled bioaccessible fraction of PM-bound TMs during mucociliary clearance, which transported PM from the tracheal and the bronchial region to the digestive system. This study provides direct evidence for TMs in airborne PM being bioaccessible TMs are likely to possess an enhanced digestive toxic potential due to airborne PM pollution.
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Affiliation(s)
- Peng Gao
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, 510275, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Huiyuan Guo
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA, 01003, USA
| | - Zhaohan Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Cuiyun Ou
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Jian Hang
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, 510275, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Qi Fan
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, 510275, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Chuan He
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Bing Wu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Yujie Feng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA, 01003, USA.
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Zhang Y, Xu H, Jiang S, Wang F, Ou C, Zhao Y, Ma L, Li Y. First Report of Colletotrichum truncatum Causing Anthracnose on the Berry Stalk and the Rachis of Kyoho Grape (Vitis labruscana × V. vinifera) Clusters in Hebei, China. Plant Dis 2018; 102:PDIS02180275PDN. [PMID: 30095322 DOI: 10.1094/pdis-02-18-0275-pdn] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Affiliation(s)
- Y Zhang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - H Xu
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - S Jiang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - F Wang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - C Ou
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - Y Zhao
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - L Ma
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Germplasm Resources Utilization, Ministry of Agriculture, and Research Institute of Pomology, Chinese Academy of Agricultural Sciences, Xingcheng 125100, China
| | - Y Li
- Hebei Agricultural University, National Engineering Research Center for Agriculture in Northern Mountainous Areas, Biological Control Center of Plant Diseases and Plant Pests of Hebei Province, Baoding 071001, China
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22
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Deng Q, Ou C, Chen J, Xiang Y. Particle deposition in tracheobronchial airways of an infant, child and adult. Sci Total Environ 2018; 612:339-346. [PMID: 28854390 DOI: 10.1016/j.scitotenv.2017.08.240] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 08/22/2017] [Accepted: 08/22/2017] [Indexed: 05/04/2023]
Abstract
BACKGROUND Particle deposition in human airways is important for assessing both health effects of inhaled particles and therapeutic efficacy of inhaled drug aerosols, but is not well understood for infants and children. OBJECTIVE We investigate particle deposition in infants and children by using computational fluid dynamics (CFD), and compare this with particle deposition in adults. METHODS We chose three population age groups: 7-month infant, 4-year old child, and 20-year old adult. Both airway structures and breathing conditions are considered to vary as a human grows from infancy to adulthood. We investigated deposition of micron-size particles (1-10μm) in both the upper (G3-G6) and lower (G9-G12) tracheobronchial (TB) airways under sedentary conditions. RESULTS We found that particle deposition in both upper and lower airways is the highest in an infant, next in a child, and lowest in an adult. As age increases, particle deposition decreases in the upper airways but increases in the lower. For infants, inertial impaction is the dominant deposition mechanism, thus particles are deposited more in the upper airways than in the lower. However, particles are deposited more in the lower airways than in the upper in adults, as gravitational sedimentation is the dominant deposition mechanism. CONCLUSION Given the differences in the airway structure and particle deposition mechanisms, particle deposition in infants and children differs from that in adults, not only in the efficiency of deposition but also in the site. Our findings provide evidence that "children are not small adults".
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Affiliation(s)
- Qihong Deng
- School of Energy Science and Engineering, Central South University, Changsha, China; XiangYa School of Public Health, Central South University, Changsha, China.
| | - Cuiyun Ou
- School of Energy Science and Engineering, Central South University, Changsha, China
| | - Jiao Chen
- School of Energy Science and Engineering, Central South University, Changsha, China
| | - Yuguang Xiang
- School of Energy Science and Engineering, Central South University, Changsha, China
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Xu B, Lefringhouse J, Liu Z, West D, Baldwin LA, Ou C, Chen L, Napier D, Chaiswing L, Brewer LD, St Clair D, Thibault O, van Nagell JR, Zhou BP, Drapkin R, Huang JA, Lu ML, Ueland FR, Yang XH. Inhibition of the integrin/FAK signaling axis and c-Myc synergistically disrupts ovarian cancer malignancy. Oncogenesis 2017; 6:e295. [PMID: 28134933 PMCID: PMC5294249 DOI: 10.1038/oncsis.2016.86] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/23/2016] [Accepted: 11/16/2016] [Indexed: 02/06/2023] Open
Abstract
Integrins, a family of heterodimeric receptors for extracellular matrix, are promising therapeutic targets for ovarian cancer, particularly high-grade serous-type (HGSOC), as they drive tumor cell attachment, migration, proliferation and survival by activating focal adhesion kinase (FAK)-dependent signaling. Owing to the potential off-target effects of FAK inhibitors, disruption of the integrin signaling axis remains to be a challenge. Here, we tackled this barrier by screening for inhibitors being functionally cooperative with small-molecule VS-6063, a phase II FAK inhibitor. From this screening, JQ1, a potent inhibitor of Myc oncogenic network, emerged as the most robust collaborator. Treatment with a combination of VS-6063 and JQ1 synergistically caused an arrest of tumor cells at the G2/M phase and a decrease in the XIAP-linked cell survival. Our subsequent mechanistic analyses indicate that this functional cooperation was strongly associated with the concomitant disruption of activation or expression of FAK and c-Myc as well as their downstream signaling through the PI3K/Akt pathway. In line with these observations, we detected a strong co-amplification or upregulation at genomic or protein level for FAK and c-Myc in a large portion of primary tumors in the TCGA or a local HGSOC patient cohort. Taken together, our results suggest that the integrin–FAK signaling axis and c-Myc synergistically drive cell proliferation, survival and oncogenic potential in HGSOC. As such, our study provides key genetic, functional and signaling bases for the small-molecule-based co-targeting of these two distinct oncogenic drivers as a new line of targeted therapy against human ovarian cancer.
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Affiliation(s)
- B Xu
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - J Lefringhouse
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA.,Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, USA.,Department of Pathology, University of Kentucky, Lexington, KY, USA
| | - Z Liu
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA.,Department of Respiratory Medicine, First Affiliated Hospital of Soochow University, Jiangsu Province, PR China
| | - D West
- Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, USA.,Department of Pathology, University of Kentucky, Lexington, KY, USA
| | - L A Baldwin
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA.,Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, USA.,Department of Pathology, University of Kentucky, Lexington, KY, USA
| | - C Ou
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - L Chen
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - D Napier
- Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, USA.,Department of Pathology, University of Kentucky, Lexington, KY, USA
| | - L Chaiswing
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, USA
| | - L D Brewer
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - D St Clair
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, USA
| | - O Thibault
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - J R van Nagell
- Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, USA.,Department of Pathology, University of Kentucky, Lexington, KY, USA
| | - B P Zhou
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - R Drapkin
- Department of Gynecologic Cancer Research, Basser Center for BRCA, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - J-A Huang
- Department of Respiratory Medicine, First Affiliated Hospital of Soochow University, Jiangsu Province, PR China
| | - M L Lu
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, FL, USA
| | - F R Ueland
- Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, USA.,Department of Pathology, University of Kentucky, Lexington, KY, USA
| | - X H Yang
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA.,Department of Respiratory Medicine, First Affiliated Hospital of Soochow University, Jiangsu Province, PR China
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Lu C, Deng L, Ou C, Yuan H, Chen X, Deng Q. Preconceptional and perinatal exposure to traffic-related air pollution and eczema in preschool children. J Dermatol Sci 2016; 85:85-95. [PMID: 27865567 DOI: 10.1016/j.jdermsci.2016.11.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 10/31/2016] [Accepted: 11/08/2016] [Indexed: 12/26/2022]
Abstract
BACKGROUND Evidence linking prenatal exposure to outdoor air pollution with eczema in early childhood is scare, and the role of components of air pollution and exposure timing remains unclear. OBJECTIVES We investigated the association between exposure to air pollution during preconceptional and perinatal period and the risk of eczema in preschool children. METHODS We conducted a prospective cohort study of 2598 children aged 3-6 years in Changsha, China. The prevalence of eczema was assessed by a standardized health questionnaire administered by the parents. Individual exposures to nitrogen dioxide (NO2), sulfur dioxide (SO2) and particulate matter with an aerodynamic diameter≤10μm (PM10) during the 4th-6th and 1st-3rd month before pregnancy, entire pregnancy, and three trimesters were estimated by an inverse distance weighted (IDW) method based on concentrations measured at monitoring stations. Association between childhood eczema and exposure to air pollution was examined by logistic regression models in terms of odds ratio (OR) and 95% confidence interval (CI) for an interquartile range (IQR) increase in exposure. RESULTS Life-time prevalence of eczema in preschool children in Changsha was 28.6%. Childhood eczema was associated with traffic-related air pollutant NO2 during 3 months before pregnancy and entire pregnancy with adjusted ORs=1.19 (95% CI: 1.04-1.37) and 1.21 (95% CI: 1.03-1.42) respectively. The highest risk of eczema was observed for the 1st trimester exposure to NO2 [OR=1.26 (95% CI: 1.09-1.46)]. However, no association was detected for SO2 and PM10 exposure during any window. High-level exposure to NO2 during the whole time period significantly increased the effect of NO2 in all windows on eczema risk as compared with low-level exposure. Sensitivity analysis indicated that the association between both preconceptional and perinatal exposure to NO2 and childhood eczema was consistent and robust, and this association was modified by some personal, parental hereditary and indoor environmental factors. CONCLUSION Our findings support the hypothesis that early childhood eczema is associated with exposure to traffic-related air pollutant during both preconceptional and perinatal period, especially at a high level of exposure.
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Affiliation(s)
- Chan Lu
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China
| | - Linjing Deng
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China
| | - Cuiyun Ou
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China
| | - Hong Yuan
- Institute of Environmental Health, Central South University, Changsha, Hunan, China; The Third XiangYa Hospital, Central South University, Changsha, Hunan, China
| | - Xiang Chen
- Department of Dermatology, XiangYa Hospital, Central South University, Changsha, Hunan, China; The State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China
| | - Qihong Deng
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China; Institute of Environmental Health, Central South University, Changsha, Hunan, China; XiangYa School of Public Health, Central South University, Changsha, Hunan, China.
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25
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Li S, Zhou Y, Williams G, Jaakkola J, Ou C, Chen S, Yao T, Qin T, Wu S, Guo Y. Seasonality and temperature effects on fasting plasma glucose: A population-based longitudinal study in China. Diabetes & Metabolism 2016; 42:267-75. [DOI: 10.1016/j.diabet.2016.01.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 01/05/2016] [Accepted: 01/08/2016] [Indexed: 01/05/2023]
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Deng Q, Lu C, Ou C, Chen L, Yuan H. Preconceptional, prenatal and postnatal exposure to outdoor and indoor environmental factors on allergic diseases/symptoms in preschool children. Chemosphere 2016; 152:459-67. [PMID: 27003368 DOI: 10.1016/j.chemosphere.2016.03.032] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 02/28/2016] [Accepted: 03/08/2016] [Indexed: 05/19/2023]
Abstract
BACKGROUND Environmental factors have been found to be associated with allergic diseases, but it is unclear which environmental factor during which exposure window causes what kind of allergic diseases. OBJECTIVES We investigated association between exposure to some predominant outdoor and indoor environmental factors during preconceptional, prenatal, and postnatal periods and allergic diseases/symptoms in 2598 children in China. METHODS Children's lifetime incidence of allergic diseases and current prevalence of allergic symptoms and exposure to indoor new furniture/redecoration and mold/dampness was surveyed by a questionnaire. Exposure to outdoor air pollutants was estimated by the concentrations measured at air quality monitoring stations. Multiple logistic regression model was used to evaluate the associations between outdoor air pollutants and indoor environmental factors and allergic diseases (asthma, allergic rhinitis, and eczema) and symptoms (wheezing, night cough, and rhinitis-like). RESULTS We found that preconceptional, prenatal, and postnatal exposure to outdoor industrial and traffic air pollutants were significantly associated with increase in the risk of childhood asthma, and also positively associated with allergic rhinitis and eczema. However, we cannot distinguish the effect of outdoor air pollutants and exposure windows because of their high correlations. New furniture was associated with eczema and allergic rhinitis during postnatal exposure, but redecoration associated with asthma and eczema during prenatal exposure. Indoor visible mold/damp stains was significant for eczema during prenatal exposure and asthma during postnatal exposure respectively, but window condensation was significant for all childhood allergic diseases during both prenatal and postnatal exposures. Allergic symptoms in children were found to be associated with exposure to indoor factors only. CONCLUSIONS Associations between outdoor air pollutants and indoor environmental factors and childhood allergic diseases/symptoms were divergent and related to the timing of exposure.
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Affiliation(s)
- Qihong Deng
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China; School of Public Health, Central South University, Changsha, Hunan, China; Institute of Environmental Health, Central South University, Changsha, Hunan, China.
| | - Chan Lu
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China
| | - Cuiyun Ou
- School of Energy Science and Engineering, Central South University, Changsha, Hunan, China
| | - Lv Chen
- School of Public Health, Central South University, Changsha, Hunan, China
| | - Hong Yuan
- Institute of Environmental Health, Central South University, Changsha, Hunan, China; The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
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27
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Winemiller KO, McIntyre PB, Castello L, Fluet-Chouinard E, Giarrizzo T, Nam S, Baird IG, Darwall W, Lujan NK, Harrison I, Stiassny MLJ, Silvano RAM, Fitzgerald DB, Pelicice FM, Agostinho AA, Gomes LC, Albert JS, Baran E, Petrere M, Zarfl C, Mulligan M, Sullivan JP, Arantes CC, Sousa LM, Koning AA, Hoeinghaus DJ, Sabaj M, Lundberg JG, Armbruster J, Thieme ML, Petry P, Zuanon J, Torrente Vilara G, Snoeks J, Ou C, Rainboth W, Pavanelli CS, Akama A, van Soesbergen A, Sáenz L. Balancing hydropower and biodiversity in the Amazon, Congo, and Mekong. Science 2016; 351:128-9. [PMID: 26744397 DOI: 10.1126/science.aac7082] [Citation(s) in RCA: 346] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
| | - P B McIntyre
- See supplementary materials for author affiliations
| | - L Castello
- See supplementary materials for author affiliations
| | | | - T Giarrizzo
- See supplementary materials for author affiliations
| | - S Nam
- See supplementary materials for author affiliations
| | - I G Baird
- See supplementary materials for author affiliations
| | - W Darwall
- See supplementary materials for author affiliations
| | - N K Lujan
- See supplementary materials for author affiliations
| | - I Harrison
- See supplementary materials for author affiliations
| | | | | | | | - F M Pelicice
- See supplementary materials for author affiliations
| | | | - L C Gomes
- See supplementary materials for author affiliations
| | - J S Albert
- See supplementary materials for author affiliations
| | - E Baran
- See supplementary materials for author affiliations
| | - M Petrere
- See supplementary materials for author affiliations
| | - C Zarfl
- See supplementary materials for author affiliations
| | - M Mulligan
- See supplementary materials for author affiliations
| | - J P Sullivan
- See supplementary materials for author affiliations
| | - C C Arantes
- See supplementary materials for author affiliations
| | - L M Sousa
- See supplementary materials for author affiliations
| | - A A Koning
- See supplementary materials for author affiliations
| | | | - M Sabaj
- See supplementary materials for author affiliations
| | - J G Lundberg
- See supplementary materials for author affiliations
| | - J Armbruster
- See supplementary materials for author affiliations
| | - M L Thieme
- See supplementary materials for author affiliations
| | - P Petry
- See supplementary materials for author affiliations
| | - J Zuanon
- See supplementary materials for author affiliations
| | | | - J Snoeks
- See supplementary materials for author affiliations
| | - C Ou
- See supplementary materials for author affiliations
| | - W Rainboth
- See supplementary materials for author affiliations
| | | | - A Akama
- See supplementary materials for author affiliations
| | | | - L Sáenz
- See supplementary materials for author affiliations
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28
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Lu XX, Zhu LQ, Pang F, Sun W, Ou C, Li Y, Cao J, Hu YL. Relationship between RUNX3 methylation and hepatocellular carcinoma in Asian populations: a systematic review. Genet Mol Res 2014; 13:5182-9. [PMID: 25061743 DOI: 10.4238/2014.july.7.11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Runt-related transcription factor 3 (RUNX3) is a potential tumor suppressor that is frequently hypermethylated in hepatocellular carcinoma (HCC). The present meta-analysis of case-control studies was carried out to determine whether RUNX3 hypermethylation is associated with HCC. The PubMed, Embase, and Chinese National Knowledge Infrastructure databases were searched for all relevant studies published between May 2000 and May 2012. A total of 11 studies were identified, and 8 studies involving 491 patients with HCC and 409 patients without tumors were found to satisfy the inclusion criteria for the meta-analysis. All tissue samples were from Asian populations. There was significant heterogeneity between the studies. Over the entire sample, the odds ratio (OR) of RUNX3 promoter methylation was 18.5 [95% confidence interval (CI), 11.6-29.6] for HCC tissues relative to control tissues. The ORs of RUNX3 methylation were 16.6 (95%CI = 6.5-42.4) for tumor tissues relative to tumor-adjacent tissues in patients with HCC, 67.3 (95%CI = 13.0-348.5) for tumor tissues from patients with HCC relative to liver tissues from patients with non-neoplastic liver diseases, and 3.26 (95%CI = 1.54-6.90) for tissues from patients with hepatitis C virus (HCV)- related HCC relative to liver tissues from patients with HCC unrelated to HCV. There was no association between RUNX3 methylation and age, gender, pathological stage, or hepatitis B virus infection in HCC tissues. Methylation of the RUNX3 promoter strongly correlated with HCC in Asian populations, especially in individuals with HCV-related HCC, and may be a useful marker for HCC diagnosis in these populations.
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Affiliation(s)
- X X Lu
- Research Department, Tumor Hospital of Guangxi Medical University, Nanning, China
| | - L Q Zhu
- Research Department, Tumor Hospital of Guangxi Medical University, Nanning, China
| | - F Pang
- Guangxi Medical University, Nanning, China
| | - W Sun
- Research Department, Tumor Hospital of Guangxi Medical University, Nanning, China
| | - C Ou
- Research Department, Tumor Hospital of Guangxi Medical University, Nanning, China
| | - Y Li
- Research Department, Tumor Hospital of Guangxi Medical University, Nanning, China
| | - J Cao
- Research Department, Tumor Hospital of Guangxi Medical University, Nanning, China
| | - Y L Hu
- Medical Scientific Research Centre, Guangxi Medical University, Nanning, China
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Wong CM, Peiris JSM, Yang L, Chan KP, Thach TQ, Lai HK, Lim WWL, Hedley AJ, He J, Chen P, Ou C, Deng A, Zhang X, Zhou D, Ma S, Chow A. Effect of influenza on cardiorespiratory and all-cause mortality in Hong Kong, Singapore and Guangzhou. Hong Kong Med J 2012; 18 Suppl 2:8-11. [PMID: 22311353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
Abstract
1. Using a common modelling approach, mortality attributable to influenza was higher in the two subtropical cities Guangzhou and Hong Kong than in the tropical city Singapore. 2. The virus activity appeared more synchronised in subtropical cities, whereas seasonality of influenza tended to be less marked in the tropical city. 3. High temperature was associated with increased mortality after influenza infection in Hong Kong, whereas relative humidity was an effect modifier for influenza in Guangzhou. No effect modification was found for Singapore. 4. Seasonal and environmental factors probably play a more important role than socioeconomic factors in regulating seasonality and disease burden of influenza. Further studies are needed in identifying the mechanism behind the regulatory role of environmental factors.
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Affiliation(s)
- C M Wong
- Department of Community Medicine and School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong
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Hsu S, Tseng Y, Liu J, Shih S, Ou C, Chang L, Chen Y, Hong K, Melillo G, Yang L. TLC388, a Novel Topotecan Derivative, as a Chemoradiosensitizer. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Mitchell JA, Ou C, Chen Z, Nishimura T, Lye SJ. Parathyroid hormone-induced up-regulation of connexin-43 messenger ribonucleic acid (mRNA) is mediated by sequences within both the promoter and the 3'untranslated region of the mRNA. Endocrinology 2001; 142:907-15. [PMID: 11159864 DOI: 10.1210/endo.142.2.7930] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The gap junction protein connexin 43 (Cx43) mediates communication between osteoblasts and is important for maximal PTH responsiveness. We examined the role of the Cx43 promoter and messenger RNA 3' untranslated region (UTR) in conferring responsiveness to PTH in the rat osteosarcoma cell line UMR-106. PTH induced a 4-fold increase in luciferase activity of a reporter construct containing 1.6 kb 5' of the transcription start site. Deletion analysis of the promoter localized responsive sequences to between -31 to +1 bp. PTH treatment of transgenic mice containing the 1.6 kb promoter luciferase construct induced increases in luciferase and Cx43 immunoreactivity in bone cells underlying the tibial growth plate. The full Cx43 3'UTR conferred a 3-fold response to PTH when placed 3' of a CMV-luciferase construct. Deletion analysis localized responsive sequences to between 2510 and 3132 of the 3'UTR. Cloning of this segment 5' of the CMV promoter disrupted the PTH response, indicating this sequence does not function as an enhancer. Sequences within the promoter conferred responsiveness to forskolin, whereas the 3'UTR responded to both TPA and forskolin. These data indicate that PTH responsive sequences are present in the Cx43 promoter and 3'UTR, suggesting that transcriptional and posttranscriptional pathways operate to regulate PTH-induced Cx43 expression in osteoblast cells.
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Affiliation(s)
- J A Mitchell
- Program in Development and Fetal Health, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
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Shulman RJ, Ou C, Reed T, Gardner P. Central venous catheters versus peripheral veins for sampling blood levels of commonly used drugs. JPEN J Parenter Enteral Nutr 1998; 22:234-7. [PMID: 9661125 DOI: 10.1177/0148607198022004234] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Our objective was to compare the accuracy of drug levels in blood samples obtained from central venous catheters with those from peripheral blood samples taken to monitor various drug levels. METHODS Pediatric patients with central venous catheters receiving aminoglycosides, vancomycin, or cyclosporine had central and peripheral blood samples obtained within 5 minutes of each other and analyzed simultaneously. We ascertained how well blood levels from central venous catheters compared with those from peripheral blood (the criterion standard). RESULTS There were no clinically significant differences between central and peripheral values for amikacin, gentamicin, tobramycin, and vancomycin (both peaks and troughs). Preliminary data indicated that oral cyclosporine can be monitored via central venous catheter. In contrast, there was poor agreement between peripheral and central values when cyclosporine was administered by IV. CONCLUSIONS Amikacin, gentamicin, tobramycin, vancomycin, and probably oral cyclosporine can be monitored accurately via central venous catheter. In contrast, IV cyclosporine should be monitored via peripheral blood.
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Affiliation(s)
- R J Shulman
- US Department of Agriculture/Agriculture Research Service Children's Nutrition Research Center, Department of Pediatrics; Houston, TX, USA
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Amend J, Ou C, Ryan-MacFarlane C, Anderson PJ, Amend N, Biro GP. Systemic responses to SFHS-infusion in hemorrhaged dogs. Artif Cells Blood Substit Immobil Biotechnol 1996; 24:19-34. [PMID: 8714716 DOI: 10.3109/10731199609117428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Anesthetized mongrel (weight range: 16-27 Kg) dogs were prepared for monitoring hemodynamics, blood flow distribution, plasma colloid osmotic pressure and renal functional parameters at various intervals. Removal of 35 ml/Kg blood resulted in marked drop and only partial spontaneous recovery in systemic and pulmonary arterial pressures, cardiac output and organ blood flows (> 50% flow-decrements occurred in kidney, spleen, heart, gut and pancreas); plasma colloid osmotic pressure as well as urine output and creatinine clearance also fell. Group I (n = 6) of dogs was transfused after 45 minutes of hypovolemia with their own anticoagulated blood, while Group II (n = 6) received an equal volume of unmodified 6% stromafree hemoglobin solution (SFHS). Comparison of the two groups' responses to resuscitation yielded some differences. There was a significant overshoot (30 mmHg) in systemic arterial blood pressure accompanied by bradycardia in Group II only. Cardiac output recovered in both groups but was less well sustained in Group II. Cerebral blood flow rose higher and hepatic arterial flow-increment was less in Group II than in Group I; the responses to resuscitation in the other organs were comparable. Colloid osmotic pressure decreased in Group I whereas it rose immediately after resuscitation in Group II, declining thereafter with a converging trend and 30 minutes thereafter the differences were not significant between the groups. Urine excretion and creatinine clearance recovered to comparable extents in both groups, but N-acetyl-beta-D-glucosaminidase (N.A.G.) excretion rose over 10-fold higher in Group II than in Group I. These experiments have defined the response of bled animals to resuscitation with unmodified, unpurified SFHS, when compared to resuscitation with whole blood, showing a less well sustained but adequate hemodynamic and renal functional recovery while revealing indications of early renal tubular cellular injury, providing baseline comparison for testing highly purified and modified hemoglobin solutions.
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Affiliation(s)
- J Amend
- Dept. of Physiology, University of Ottawa, ON, Canada
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Abstract
STUDY OBJECTIVE To determine the digestion and absorption of lactose, a combination of lactose and glucose polymers, and glucose polymers alone in infants born at 28 to 42 weeks of gestation. DESIGN Each infant received the three carbohydrate solutions (85 gm/L concentration) in random order. SETTING Tertiary care urban children's hospital. INTERVENTIONS A double-lumen perfusion catheter was placed in the duodenum-jejunum. Absorption was defined as the disappearance of the carbohydrate and all its components (e.g., for lactose: galactose, glucose). MEASUREMENTS AND MAIN RESULTS Absorption of lactose was less than that of the lactose-glucose polymer combination and the glucose polymers alone. There was no relationship between lactose absorption and postnatal age, whereas absorption of the lactose-glucose polymer combination and the glucose polymers alone correlated with age. Lactose absorption was not related to the number of days that the infants received full-strength feedings or the total number of days of feeding before the study, whereas absorption of both the lactose-glucose polymer combination and the glucose polymers alone was related to both. Absorption of the three solutions was not related to gestational age or to the number of days before the initial feeding. Lactose absorption was greater in infants who received formula alone than in infants fed formula together with human milk. CONCLUSIONS Premature infants do not digest and absorb lactose as well as glucose polymers. However, lactose does not impair the absorption of glucose polymers. Lactose assimilation is not affected by maturation, but the type of diet may affect lactose digestion and absorption. In contrast, digestion and absorption of glucose polymers are related to both postnatal age and diet.
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Affiliation(s)
- R J Shulman
- U.S. Department of Agriculture/Agricultural Research Service (USDA/ARS) Children's Nutrition Research Center, Houston, TX, USA
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Biro GP, Ou C, Ryan-MacFarlane C, Anderson PJ. Oxyradical generation after resuscitation of hemorrhagic shock with blood or stroma-free hemoglobin solution. Artif Cells Blood Substit Immobil Biotechnol 1995; 23:631-45. [PMID: 8556138 DOI: 10.3109/10731199509117977] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Hypovolemic states are characterized by inadequate tissue perfusion; when this state is reversed, the reintroduction of oxygen is accompanied by the excess generation of oxyradicals and these, in turn, may cause "reperfusion injury" in susceptible tissues. When hemoglobin solution is used to resuscitate the hypovolemic state, the generation of oxyradicals may be enhanced by catalytic means. The generation of oxyradicals was estimated in dogs subjected to the acute removal of 35 ml/Kg blood, and resuscitated 45 mins thereafter with an equal volume of either autologous blood (Group I, n = 6) or 6% stromafree hemoglobin solution (S.F.H.S.) (Group II, n = 6). Hepatic and pancreatic enzymes were measured in blood drawn at intervals. The hypovolemic state was characterized by profound hypotension which was reversed by resuscitation. Oxyradical generation in arterial blood samples, drawn at various times, was estimated by the generation of oxidation products (2,3- and 2,5-dihydroxybenzoic acid) of exogenously administered sodium salicylate, determined by HPLC in plasma samples extracted with diethyl ether. Salicylate oxidation products rose significantly above the baseline value in Group I dogs, whereas they rose 5-6-fold higher than the baseline values in those of Group II. The actual values attained and the increments were significantly (p < .05) greater in Group II than in Group I. In the group resuscitated with S.F.H.S., catalytically active iron concentration in plasma also rose 10-12-fold higher and was associated with spuriously elevated levels of gamma-glutamyl transferase due to interference with the assay. These findings are consistent with the hypothesis that blood-resuscitation of hypovolemic shock is accompanied by oxyradical generation of a modest degree; in contrast, S.F.H.S.-resuscitation introduces catalytically active iron and is accompanied by oxyradical generation of a significantly greater degree.
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Affiliation(s)
- G P Biro
- Dept. of Physiology, Faculty of Medicine, University of Ottawa, ON, Canada
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Leenen FH, Harmsen E, Yu H, Ou C. Effects of dietary sodium on central and peripheral ouabain-like activity in spontaneously hypertensive rats. Am J Physiol 1993; 264:H2051-5. [PMID: 8322933 DOI: 10.1152/ajpheart.1993.264.6.h2051] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
High dietary Na+ intake enhances pressor and sympathoexcitatory responses in spontaneously hypertensive rats (SHR) but not Wistar-Kyoto (WKY) rats. To evaluate the possible contribution of central ouabain-like activity (OLA), brain and peripheral OLA was assessed in SHR vs. WKY rats at 4 wk of age and after 2 and 4 wk of high vs. control Na+ intake started at 4 wk of age. In SHR, hypertension developed with maturation and was exacerbated by high Na+ intake. With control Na+ intake, SHR showed higher OLA at 4, 6, and 8 wk of age in the pituitary and hypothalamus and also by 8 wk in the adrenals and left ventricle but not in plasma. High Na+ intake increased OLA in all tissues examined in both WKY rats and SHR. After 2 wk on high Na+, only OLA in hypothalamus and pituitary was higher in SHR vs. WKY rats; after 4 wk on high Na+, peripheral (i.e., adrenals, left ventricle, and plasma) OLA was also higher. These results indicate that in SHR the development of hypertension is associated early on with increases in central OLA and in a later phase with increases in peripheral OLA as well. High Na+ intake increases OLA in both SHR and WKY rats, but the higher OLA may affect sympathetic activity and blood pressure only in SHR.
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Affiliation(s)
- F H Leenen
- Hypertension Unit, University of Ottawa Heart Institute, Ontario, Canada
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Abstract
The phospholipase D (PL D), which catalyzes the formation of phosphatidic acid (PA), was studied in rat myocardium using 14C-labelled phosphatidylcholine (PC) as an exogenous substrate. Subcellular distribution experiments indicated the presence of PL D in particulate fractions only. Different procedures for the isolation of purified cardiac subcellular organelles showed the presence of PL D in sarcolemma (SL), sarcoplasmic reticulum (SR) and mitochondria with 14-, 11- and 5-fold enrichment when compared to the homogenate value, respectively. The activity of SL PL D was observed over a narrow acid pH range with an optimum at 6.5, and it showed a high specificity for PC while phosphatidylethanolamine and phosphatidylinositol showed a low rate of hydrolysis. Under optimal conditions, PA formation was linear for a 90-min period of incubation and the reaction rate was constant for 10 to 100 micrograms SL protein in the assay medium. The SR PL D displayed properties similar to those seen with the SL PL D. In membrane fractions PL D was also found to catalyze a transphosphatidylation reaction for the synthesis of phosphatidylglycerol. Assessment of the intramembranal levels of radioactive 1,2-diacylglycerol (DAG) in the absence or presence of KF suggested the presence of an active PA phosphohydrolase activity. This study indicates that a PC-specific PL D activity is localized in different membrane systems of the myocardium and may be associated with PA phosphohydrolase to act in a coordinated manner. The functional significance of PL D-dependent formation of PA in cardiac membranes is discussed.
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Affiliation(s)
- V Panagia
- Division of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Winnipeg, Manitoba, Canada
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Moriya M, Ou C, Bodepudi V, Johnson F, Takeshita M, Grollman AP. Site-specific mutagenesis using a gapped duplex vector: a study of translesion synthesis past 8-oxodeoxyguanosine in E. coli. Mutat Res 1991; 254:281-8. [PMID: 2052015 DOI: 10.1016/0921-8777(91)90067-y] [Citation(s) in RCA: 237] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have constructed a gapped plasmid vector in which a single defined lesion is introduced, site-specifically, within a single-strand region. Efficiency of translesional synthesis is determined by the number of colonies recovered following transformation of E. coli. The nucleotide sequence of progeny plasmids in the gapped region of the vector reflects incorporation of bases opposite and near the lesion. The analysis detects non-mutagenic as well as mutagenic events. This system was used to establish the mutagenic potential of 2'-deoxy-7,8-dihydro-8-oxoguanosine (8-oxodG), a lesion produced by the action of active oxygen species on DNA. The presence of 8-oxodG did not affect the number of transformants recovered. Most transformants (greater than 99%) contained G:C pairs at the site of the lesion; however, a limited number of targeted G----T transversions were observed in the presence and absence of SOS induction. Base substitutions neighboring the lesion, reported for an in vitro system, were not observed. We conclude that the 8-oxodG lesion in DNA is weakly mutagenic in E. coli.
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Affiliation(s)
- M Moriya
- Department of Pharmacological Sciences, State University of New York, Stony Brook 11794-8651
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Kaneko M, Panagia V, Paolillo G, Majumder S, Ou C, Dhalla NS. Inhibition of cardiac phosphatidylethanolamine N-methylation by oxygen free radicals. Biochim Biophys Acta 1990; 1021:33-8. [PMID: 2153025 DOI: 10.1016/0005-2736(90)90380-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study was undertaken to examine the effects of oxygen free radicals on phosphatidylethanolamine (PE) N-methylation in rat heart sarcolemmal (SL) and sarcoplasmic reticular (SR) membranes. Three catalytic sites involved in the sequential methyl transfer reaction were studied by assaying the incorporation of radiolabeled methyl groups from S-adenosyl-L-methionine (0.055, 10, and 150 microM) into SL or SR PE molecules under optimal conditions. In the presence of xanthine + xanthine oxidase (superoxide anion radicals generating system), PE N-methylation was inhibited at site I and III in the heavy SL fraction isolated by the hypotonic shock-LiBr treatment method. In the light SL fraction isolated by sucrose-density gradient, a significant inhibition of PE N-methylation was seen at all three sites. These inhibitory effects of xanthine + xanthine oxidase on PE N-methylation were prevented by the addition of superoxide dismutase. Hydrogen peroxide showed a significant inhibition of PE N-methylation at site I in the heavy SL fraction, and at site I and II in the light SL fraction. Catalase blocked the inhibitory effects of hydrogen peroxide. The effects of both xanthine + xanthine oxidase and hydrogen peroxide on the SR membranes were similar to those seen for the heavy SL fraction. These results suggest that, in addition to lipid peroxidation, the oxygen free radicals may affect the function of cardiac membranes by decreasing the phospholipid N-methylation activity.
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Affiliation(s)
- M Kaneko
- Division of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Winnipeg, Canada
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Abstract
Poor penetration of antibiotics into paralyzed tissue may contribute to the difficulty of curing soft tissue infections in paralyzed limbs. A novel model of spinal cord hemisection was used to induce paralysis of one hind leg in mice. Five, 10, or 20 days after induction of paralysis, six groups of 10 mice were injected intravenously with a single dose or with four sequential doses of cefepime, a new broad-spectrum cephalosporin, and then sacrificed. High-performance liquid chromatography was used to compare cefepime levels in soft tissue homogenates of paralyzed and normal hind legs; no significant differences were found in any group. Factors other than antibiotic delivery may be responsible for difficulty in curing infections in paralyzed soft tissue.
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Affiliation(s)
- R Darouiche
- Medical Service (Infectious Disease Section), Houston Veterans Administration Medical Center, Texas
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Yang WK, d'Auriol L, Yang DM, Kiggnas JO, Ou C, Périès J, Emanoil-Ravicovitch R. Restricted infectivity of ecotropic type C retroviruses in mouse teratocarcinoma cells: studies on viral DNA intermediates. J Supramol Struct 1980; 14:223-32. [PMID: 6262577 DOI: 10.1002/jss.400140211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Replication of Gross strain N-tropic type C retrovirus was markedly restricted in a pluripotential undifferentiated embryonal cell line (PCC4) of murine teratocarcinoma, whereas the same virus could cause productive infection in a myoblast-derived differentiated line (PCD1) of the same tumor origin. To investigate the restriction mechanism, we compared the initial viral DNA formation in these two cell lines. Analyses by means of a modified Hirt extraction procedure and a modified Southern gel transfer method indicated that PCC4 and PCD1 cells supported the synthesis of viral DNA intermediates after inoculation of the Gross virus. In both cells, a linear DNA duplex (from III viral DNA) appeared at 4 hr, reached a maximal level at 8-9 hr, and declined rapidly thereafter, while two closed-circular supercoiled DNA duplexes (form I viral DNA) showed their appearance, increase and decline in the 8-24 hr period. During the period from 34 to 78 hr after virus inoculation, another burst of viral DNA synthesis occurred in PCD1 cells, presumably due to secondary virus infection, while at this period both form III and form I viral DNAs became undetectable in PCC4 cells. The Hirt supernatant DNAs prepared from PCD1 and PCC4 cells 10 hr after virus inoculation were equally infectious for NIH3T3 cells in a DNA transfection, although one positive result with PCD1 cells might suggest a difference between the two cell types in this aspect. These results indicate that restriction of type C retrovirus in undifferentiated embryonal carcinoma cells occurs at a step subsequent to formation and maturation of viral DNA intermediates.
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Schugar HJ, Ou C, Thich JA, Potenza JA, Lalancette RA, Furey W. Letter: Molecular structure and copper(II)-mercaptide charge-transfer spectra of a novel Cu14(SC(CH3)2CH2NH2)12Cl cluster. J Am Chem Soc 1976; 98:3047-8. [PMID: 1262637 DOI: 10.1021/ja00426a078] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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