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Liu HF, Hu XZ, Huang RW, Guo ZH, Gao JR, Xiang M, Lu R, Ban D, Liu CY, Wang YY, Li W, Li Y, Guo YJ, Lu Q, Fu HM. Evaluation of disease severity and prediction of severe cases in children hospitalized with influenza A (H1N1) infection during the post-COVID-19 era: a multicenter retrospective study. BMC Pediatr 2024; 24:234. [PMID: 38566022 PMCID: PMC10985932 DOI: 10.1186/s12887-024-04645-x] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 02/13/2024] [Indexed: 04/04/2024] Open
Abstract
BACKGROUND The rebound of influenza A (H1N1) infection in post-COVID-19 era recently attracted enormous attention due the rapidly increased number of pediatric hospitalizations and the changed characteristics compared to classical H1N1 infection in pre-COVID-19 era. This study aimed to evaluate the clinical characteristics and severity of children hospitalized with H1N1 infection during post-COVID-19 period, and to construct a novel prediction model for severe H1N1 infection. METHODS A total of 757 pediatric H1N1 inpatients from nine tertiary public hospitals in Yunnan and Shanghai, China, were retrospectively included, of which 431 patients diagnosed between February 2023 and July 2023 were divided into post-COVID-19 group, while the remaining 326 patients diagnosed between November 2018 and April 2019 were divided into pre-COVID-19 group. A 1:1 propensity-score matching (PSM) was adopted to balance demographic differences between pre- and post-COVID-19 groups, and then compared the severity across these two groups based on clinical and laboratory indicators. Additionally, a subgroup analysis in the original post-COVID-19 group (without PSM) was performed to investigate the independent risk factors for severe H1N1 infection in post-COIVD-19 era. Specifically, Least Absolute Shrinkage and Selection Operator (LASSO) regression was applied to select candidate predictors, and logistic regression was used to further identify independent risk factors, thus establishing a prediction model. Receiver operating characteristic (ROC) curve and calibration curve were utilized to assess discriminative capability and accuracy of the model, while decision curve analysis (DCA) was used to determine the clinical usefulness of the model. RESULTS After PSM, the post-COVID-19 group showed longer fever duration, higher fever peak, more frequent cough and seizures, as well as higher levels of C-reactive protein (CRP), interleukin 6 (IL-6), IL-10, creatine kinase-MB (CK-MB) and fibrinogen, higher mechanical ventilation rate, longer length of hospital stay (LOS), as well as higher proportion of severe H1N1 infection (all P < 0.05), compared to the pre-COVID-19 group. Moreover, age, BMI, fever duration, leucocyte count, lymphocyte proportion, proportion of CD3+ T cells, tumor necrosis factor α (TNF-α), and IL-10 were confirmed to be independently associated with severe H1N1 infection in post-COVID-19 era. A prediction model integrating these above eight variables was established, and this model had good discrimination, accuracy, and clinical practicability. CONCLUSIONS Pediatric H1N1 infection during post-COVID-19 era showed a higher overall disease severity than the classical H1N1 infection in pre-COVID-19 period. Meanwhile, cough and seizures were more prominent in children with H1N1 infection during post-COVID-19 era. Clinicians should be aware of these changes in such patients in clinical work. Furthermore, a simple and practical prediction model was constructed and internally validated here, which showed a good performance for predicting severe H1N1 infection in post-COVID-19 era.
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Affiliation(s)
- Hai-Feng Liu
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China
| | - Xiao-Zhong Hu
- Department of Pediatrics, The People's Hospital of Lincang, Lincang, 677000, China
| | - Rong-Wei Huang
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China
| | - Zheng-Hong Guo
- Department of Pediatrics, Zhaotong Hospital Affiliated to Kunming Medical University, Zhaotong, 657000, China
| | - Jin-Rong Gao
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China
| | - Mei Xiang
- Department of Pediatrics, The First People's Hospital of Honghe, Honghe, 651400, China
| | - Rui Lu
- Department of Pediatrics, The People's Hospital of Wenshan, Wenshan, 663000, China
| | - Deng Ban
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China
| | - Cong-Yun Liu
- Department of Pediatrics, The People's Hospital of Baoshan, Baoshan, 678000, China
| | - Ya-Yu Wang
- Department of Pediatrics, The Third Affiliated Hospital of Dali University, Dali, 671000, China
| | - Wang Li
- Department of Pediatrics, The Fifth People's Hospital of Kunming, Kunming, 650200, China
| | - Yin Li
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China
| | - Yun-Jie Guo
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China
| | - Quan Lu
- Department of Pulmonary Medicine, Shanghai Children's Hospital, Shanghai Jiao Tong University, No. 1400 West Beijing Road, Jinan District, Shanghai, 200040, China.
| | - Hong-Min Fu
- Department of Pulmonary and Critical Care Medicine, Yunnan Key Laboratory of Children's Major Disease Research, Yunnan Medical Center for Pediatric Diseases, Kunming Children's Hospital, Kunming Medical University, No. 28, Shulin Street, Xishan District, Kunming, 650034, China.
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Wang Q, Khosropanah P, van der Kuur J, de Lange G, Audley MD, Aminaei A, Ilyas S, Ridder ML, van der Linden AJ, Bruijn MP, van der Tak F, Gao JR. Frequency division multiplexing readout of a transition edge sensor bolometer array with microstrip-type electrical bias lines. Rev Sci Instrum 2022; 93:124901. [PMID: 36586892 DOI: 10.1063/5.0108786] [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] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 11/26/2022] [Indexed: 06/17/2023]
Abstract
We demonstrate multiplexed readout of 43 transition edge sensor (TES) bolometers operating at 90 mK using a frequency division multiplexing (FDM) readout chain with bias frequencies ranging from 1 to 3.5 MHz and a typical frequency spacing of 32 kHz. We improve the previously reported performance of our FDM system by two important steps. First, we replace the coplanar wires with microstrip wires, which minimize the cross talk from mutual inductance. From the measured electrical cross talk (ECT) map, the ECT of all pixels is carrier leakage dominated. Only five pixels show an ECT level higher than 1%. Second, we reduce the thermal response speed of the TES detectors by a factor of 20 by increasing the heat capacity of the TES, which allows us to bias all TES detectors below 50% in transition without oscillations. We compare the current-voltage curves and noise spectra of the TESs measured in single-pixel mode and multiplexing mode. We also compare the noise equivalent power (NEP) and the saturation power of the bolometers in both modes, where 38 pixels show less than 10% difference in NEP and 5% difference in saturation power when measured in the two different modes. The measured noise spectrum is in good agreement with the simulated noise based on measured parameters from an impedance measurement, confirming that our TES is dominated by phonon noise.
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Affiliation(s)
- Q Wang
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - P Khosropanah
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - J van der Kuur
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - G de Lange
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - M D Audley
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - A Aminaei
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - S Ilyas
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - M L Ridder
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - A J van der Linden
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - M P Bruijn
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - F van der Tak
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - J R Gao
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen and Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
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Jia XX, Xu K, Che BB, Gao JR, Huang ZY, Wang J, Wei XX, Le KL, Gong ZY, Sun YQ, Xie CC, Xi JC, Cheng YZ, Zhuyan ZY, Ding Y, Chen D. [Comparative analysis on prevalence of tobacco and e-cigarettes uses in junior middle school students in Shanghai, 2013 and 2019]. Zhonghua Liu Xing Bing Xue Za Zhi 2022; 43:1408-1414. [PMID: 36117347 DOI: 10.3760/cma.j.cn112338-20211012-00786] [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] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To examine the prevalence and trend of tobacco and e-cigarettes uses and identify the influencing factors for smoking behavior in junior middle school students in Shanghai, and provide data support and scientific basis for the development of tobacco control intervention strategy in adolescents. Methods: Multi-stage stratified random sampling method was used to select junior middle school students in 8 districts and 10 districts in Shanghai in 2013 and in 2019 respectively. Information about tobacco and e-cigarettes uses in the students were collected by using self-administrated questionnaire. The prevalence of tobacco and e-cigarettes uses were calculated, the difference between two years was compared with χ2 test. The influencing factors were identified by multivariate logistic regression analysis. Results: In 2019, the current smoking rate was 0.6% in junior middle school students in Shanghai, and the smoking attempt rate was 2.9%, both were lower than the levels in 2013 (0.7% and 6.9%). The current use rate of e-cigarettes was 0.6% in 2019,with no significant change compared with 2013 (0.6%). The proportion of the students who had heard of e-cigarettes in 2019 (78.4%) was higher than that in 2013 (47.2%). In 2019, the second-hand smoke (SHS) exposure rate at home, in both indoor and outdoor public places and on public transportations was 72.5%, which was slightly lower than the level in 2013 (73.0%), the differences were all significant (P<0.05). In 2019, the students seeing close friend smoking (OR=27.381, 95%CI: 12.037-62.287), seeing someone smoking in school (OR=2.477, 95%CI: 1.155-5.312), believing that SHS may not be harmful (OR=8.471, 95%CI: 1.464-49.005) had higher possibility of smoking. Being aged ≥15 years (compared with being aged ≤12 years, OR=8.688, 95%CI: 1.922-39.266), exposure to SHS in outdoor public place (OR=8.608, 95%CI: 1.048-70.692), close friend smoking (OR=8.115, 95%CI: 1.754-37.545) were positively associated with e-cigarettes use, and believing that smoking results in uncomfortable social contact [compared with believing that smoking results in comfortable social contact (OR=0.105,95%CI: 0.018-0.615)] were negatively associated with e-cigarettes use, the difference was significant (P<0.05). Conclusion: The prevalence of tobacco and e-cigarette uses in junior middle school students in Shanghai remained at a low level in recent years. The SHS exposure rate in junior middle school students is high. Smoking behavior of junior middle school students is closely related to personal attitude and awareness of tobacco, exposure to SHS, peer smoking and the situation of tobacco control in schools. Prevention and intervention should be carried out from multi-dimensions to effectively protect teenagers from tobacco hazards.
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Affiliation(s)
- X X Jia
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - K Xu
- Business Promotion Office, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China
| | - B B Che
- School of Public Health, Fudan University, Shanghai 200032, China
| | - J R Gao
- Shanghai Association of Tobacco Control, Shanghai 200040, China Shanghai Aging Development and Promotion Center, Shanghai 200011, China
| | - Z Y Huang
- Health Promotion Division, Shanghai Municipal Health Commission, Shanghai 200125, China
| | - J Wang
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - X X Wei
- Department of Research and Evaluation, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China
| | - K L Le
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - Z Y Gong
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - Y Q Sun
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - C C Xie
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - J C Xi
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - Y Z Cheng
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - Z Y Zhuyan
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
| | - Y Ding
- Shanghai Municipal Center for Health Promotion, Shanghai 200040, China
| | - D Chen
- Department of Tobacco Control and Behavioral Intervention, Shanghai Municipal Center for Health Promotion, Shanghai 200040, China Shanghai Association of Tobacco Control, Shanghai 200040, China
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4
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Vaccaro D, Akamatsu H, van der Kuur J, van der Hulst P, Nieuwenhuizen ACT, van Winden P, Gottardi L, den Hartog R, Bruijn MP, D'Andrea M, Gao JR, den Herder JWA, Hoogeveen RWM, Jackson B, van der Linden AJ, Nagayoshi K, Ravensberg K, Ridder ML, Taralli E, de Wit M. Frequency shift algorithm: Application to a frequency-domain multiplexing readout of x-ray transition-edge sensor microcalorimeters. Rev Sci Instrum 2021; 92:033103. [PMID: 33820098 DOI: 10.1063/5.0032011] [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] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
In the frequency-domain multiplexing (FDM) scheme, transition-edge sensors (TESs) are individually coupled to superconducting LC filters and AC biased at MHz frequencies through a common readout line. To make efficient use of the available readout bandwidth and to minimize the effect of non-linearities, the LC resonators are usually designed to be on a regular grid. The lithographic processes, however, pose a limit on the accuracy of the effective filter resonance frequencies. Off-resonance bias carriers could be used to suppress the impact of intermodulation distortions, which, nonetheless, would significantly affect the effective bias circuit and the detector spectral performance. In this paper, we present a frequency shift algorithm (FSA) to allow off-resonance readout of TESs, while preserving the on-resonance bias circuit and spectral performance, demonstrating its application to the FDM readout of an x-ray TES microcalorimeter array. We discuss the benefits in terms of mitigation of the impact of intermodulation distortions at the cost of increased bias voltage and the scalability of the algorithm to multi-pixel FDM readout. We show that with FSA, in the multi-pixel and frequencies shifted on-grid, the line noises due to intermodulation distortion are placed away from the sensitive region in the TES response and the x-ray performance is consistent with the single-pixel, on-resonance level.
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Affiliation(s)
- D Vaccaro
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - H Akamatsu
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J van der Kuur
- NWO-I/SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
| | - P van der Hulst
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - A C T Nieuwenhuizen
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - P van Winden
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - L Gottardi
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - R den Hartog
- NWO-I/SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
| | - M P Bruijn
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M D'Andrea
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J R Gao
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J W A den Herder
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - R W M Hoogeveen
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - B Jackson
- NWO-I/SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
| | - A J van der Linden
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - K Nagayoshi
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - K Ravensberg
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M L Ridder
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - E Taralli
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M de Wit
- NWO-I/SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
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Taralli E, D'Andrea M, Gottardi L, Nagayoshi K, Ridder ML, de Wit M, Vaccaro D, Akamatsu H, Bruijn MP, Gao JR. Performance and uniformity of a kilo-pixel array of Ti/Au transition-edge sensor microcalorimeters. Rev Sci Instrum 2021; 92:023101. [PMID: 33648117 DOI: 10.1063/5.0027750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/10/2021] [Indexed: 06/12/2023]
Abstract
Uniform large transition-edge sensor (TES) arrays are fundamental for the next generation of x-ray space observatories. These arrays are required to achieve an energy resolution ΔE < 3 eV full width at half maximum (FWHM) in the soft x-ray energy range. We are currently developing x-ray microcalorimeter arrays for use in the future laboratory and space-based x-ray astrophysics experiments and ground-based spectrometers. In this contribution, we report on the development and the characterization of a uniform 32 × 32 pixel array with 140 × 30 μm2 Ti/Au TESs with the Au x-ray absorber. We report on extensive measurements on 60 pixels in order to show the uniformity of our large TES array. The averaged critical temperature is Tc = 89.5 ± 0.5 mK, and the variation across the array (∼1 cm) is less than 1.5 mK. We found a large region of detector's bias points between 20% and 40% of the normal-state resistance where the energy resolution is constantly lower than 3 eV. In particular, results show a summed x-ray spectral resolution ΔEFWHM = 2.50 ± 0.04 eV at a photon energy of 5.9 keV, measured in a single-pixel mode using a frequency domain multiplexing readout system developed at SRON/VTT at bias frequencies ranging from 1 MHz to 5 MHz. Moreover, we compare the logarithmic resistance sensitivity with respect to temperature and current (α and β, respectively) and their correlation with the detector's noise parameter M, showing a homogeneous behavior for all the measured pixels in the array.
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Affiliation(s)
- E Taralli
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M D'Andrea
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - L Gottardi
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - K Nagayoshi
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M L Ridder
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M de Wit
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - D Vaccaro
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - H Akamatsu
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M P Bruijn
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J R Gao
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
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6
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Wang Q, Khosropanah P, van der Kuur J, de Lange G, Audley MD, Aminaei A, Hijmering R, Ridder ML, Ilyas S, van der Linden AJ, Bruijn MP, van der Tak F, Gao JR. Electrical cross talk of a frequency division multiplexing readout for a transition edge sensor bolometer array. Rev Sci Instrum 2021; 92:014710. [PMID: 33514257 DOI: 10.1063/5.0032929] [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] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 12/29/2020] [Indexed: 06/12/2023]
Abstract
We have characterized and mapped the electrical cross talk (ECT) of a frequency division multiplexing (FDM) system with a transition edge sensor (TES) bolometer array, which is intended for space applications. By adding a small modulation at 120 Hz to the AC bias voltage of one bolometer and measuring the cross talk response in the current noise spectra of the others simultaneously, we have for the first time mapped the ECT level of 61 pixels with a nominal frequency spacing of 32 kHz in a 61 × 61 matrix and a carrier frequency ranging from 1 MHz to 4 MHz. We find that about 94% of the pixels show an ECT level of less than 0.4%. Only the adjacent pixels reach this level, and the ECT for the rest of the pixels is less than 0.1%. We also observe higher ECT levels, up to 10%, between some of the pixels, which have bundled long, parallel coplanar wires connecting TES bolometers to inductor-capacitor filters. In this case, the high mutual inductances dominate. To mitigate this source of ECT, the coplanar wires should be replaced by microstrip wires in the array. Our study suggests that an FDM system can have a relatively low ECT level, e.g., around 0.4% if the frequency spacing is 30 kHz. Our results successfully demonstrate a low electrical cross talk for a space FDM technology.
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Affiliation(s)
- Q Wang
- SRON Netherlands Institute for Space Research, 9700 AV Groningen, The Netherlands
| | - P Khosropanah
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - J van der Kuur
- SRON Netherlands Institute for Space Research, 9700 AV Groningen, The Netherlands
| | - G de Lange
- SRON Netherlands Institute for Space Research, 9700 AV Groningen, The Netherlands
| | - M D Audley
- SRON Netherlands Institute for Space Research, 9700 AV Groningen, The Netherlands
| | - A Aminaei
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - R Hijmering
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - M L Ridder
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - S Ilyas
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - A J van der Linden
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - M P Bruijn
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - F van der Tak
- SRON Netherlands Institute for Space Research, 9700 AV Groningen, The Netherlands
| | - J R Gao
- SRON Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
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7
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Li Z, Gao JR, Song L, Wang PG, Ren JA, Wu XW, Luo SM, Zeng QJ, Weng YH, Xu XJ, Yuan QZ, Zhao J, Liao NS, Mai W, Wang F, Cao H, Wang SC, Han G, Wang DR, Wang H, Zhang J, Zhang H, Zhang DM, Liao WS, Zhao WW, Li W, Cui P, Chen X, Zhang HY, Yang T, Wang L, Gao YS, Li J, Wu JJ, Zhou W, Lyu ZJ, Fang J. [Risk factors for surgical site infection after emergency abdominal surgery: a multicenter cross-sectional study in China]. Zhonghua Wei Chang Wai Ke Za Zhi 2020; 23:1043-1050. [PMID: 33212552 DOI: 10.3760/cma.j.issn.441530-20200527-00315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: Surgical site infection (SSI) is the most common infectious complication after emergency abdominal surgery (EAS). To a large extent, most SSI can be prevented, but there are few relevant studies in China. This study mainly investigated the current situation of SSI occurrence after EAS in China, and further explored risk factors for SSI occurrence. Methods: Multi-center cross-sectional study was conducted. Clinical data of patients undergoing EAS in 33 hospitals across China between May 1, 2019 and June 7, 2019 were prospectively collected, including perioperative data and microbial culture results from infected incisions. The primary outcome was the incidence of SSI after EAS, while the secondary outcomes were postoperative hospital stay, ICU occupancy rate, length of ICU stay, hospitalization cost, and mortality within postoperative 30 days. Univariate and multivariate logistic regression models were used to analyze the risk factors of SSI after EAS. Results: A total of 660 EAS patients aged (47.9±18.3) years were enrolled in this study, including 56.5% of males (373/660). Forty-nine (7.4%) patients developed postoperative SSI. The main pathogen of SSI was Escherichia coli [culture positive rate was 32.7% (16/49)]. As compared to patients without SSI, those with SSI were more likely to be older (median 56 years vs. 46 years, U=19 973.5, P<0.001), male [71.4% (35/49) vs. 56.1% (343/611), χ(2)=4.334, P=0.037] and diabetes [14.3% (7/49) vs. 5.1% (31/611), χ(2)=5.498, P=0.015]; with-lower preoperative hemoglobin (median: 122.0 g/L vs. 143.5 g/L, U=11 471.5, P=0.006) and albumin (median: 35.5 g/L vs. 40.8 g/L, U=9452.0, P<0.001), with higher blood glucose (median: 6.9 mmol/L vs. 6.0 mmol/L, U=17 754.5, P<0.001); with intestinal obstruction [32.7% (16/49) vs. 9.2% (56/611), χ(2)=25.749, P<0.001], with ASA score 3-4 [42.9% (21/49) vs. 13.9% (85/611), χ(2)=25.563, P<0.001] and with high surgical risk [49.0% (24/49) vs. 7.0% (43/611), χ(2)=105.301, P<0.001]. The main operative procedure resulting in SSI was laparotomy [81.6%(40/49) vs. 35.7%(218/611), χ(2)=40.232, P<0.001]. Patients with SSI experienced significantly longer operation time (median: 150 minutes vs. 75 minutes, U=25 183.5, P<0.001). In terms of clinical outcome, higher ICU occupancy rate [51.0% (25/49) vs. 19.5% (119/611), χ(2)=26.461, P<0.001], more hospitalization costs (median: 44 000 yuan vs. 15 000 yuan, U=24 660.0, P<0.001), longer postoperative hospital stay (median: 10 days vs. 5 days, U=23 100.0, P<0.001) and longer ICU occupancy time (median: 0 days vs. 0 days, U=19 541.5, P<0.001) were found in the SSI group. Multivariate logistic regression analysis showed that the elderly (OR=3.253, 95% CI: 1.178-8.985, P=0.023), colorectal surgery (OR=9.156, 95% CI: 3.655-22.937, P<0.001) and longer operation time (OR=15.912, 95% CI:6.858-36.916, P<0.001) were independent risk factors of SSI, while the laparoscopic surgery (OR=0.288, 95% CI: 0.119-0.694, P=0.006) was an independent protective factor for SSI. Conclusions: For patients undergoing EAS, attention should be paid to middle-aged and elderly patients and those of colorectal surgery. Laparoscopic surgery should be adopted when feasible and the operation time should be minimized, so as to reduce the incidence of SSI and to reduce the burden on patients and medical institutions.
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Affiliation(s)
- Z Li
- Department of Emergency Surgery, the Affiliated Hospital of Qingdao University, Qingdao, Shandong 266000, China
| | - J R Gao
- Department of Emergency Surgery, the Affiliated Hospital of Qingdao University, Qingdao, Shandong 266000, China
| | - L Song
- Department of Emergency Surgery, the Affiliated Hospital of Qingdao University, Qingdao, Shandong 266000, China
| | - P G Wang
- Department of Emergency Surgery, the Affiliated Hospital of Qingdao University, Qingdao, Shandong 266000, China
| | - J A Ren
- Research Institute of General Surgery, East War Zone Hospital of PLA, Nanjing, Jiangsu 210002, China
| | - X W Wu
- Research Institute of General Surgery, East War Zone Hospital of PLA, Nanjing, Jiangsu 210002, China
| | - S M Luo
- Department of Gastrointestinal Surgery, the People's Hospital of Xinjiang Uygur Autonomous Region, Urumq, Xinjiang 830001, China
| | - Q J Zeng
- Department of General Surgery, Yueyang First People's Hospital, Yueyang, Hunan 414000, China
| | - Y H Weng
- Department of General Surgery, Shoukang Hospital, Huangshan, Anhui 245000, China
| | - X J Xu
- Department of General Surgery, the First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830001, China
| | - Q Z Yuan
- Department of Hepatobiliary Surgery, Shengli Oilfield Central Hospital, Dongying, Shandong 257000, China
| | - J Zhao
- Department of General Surgery, Shangqiu First People's Hospital, Shangqiu, Henan 476000, China
| | - N S Liao
- Department of General Surgery, Taizhou First People's Hospital, Taizhou, Zhejiang 318000, China
| | - W Mai
- Department of Gastrointestinal Surgery, the People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, Guangxi 530021, China
| | - F Wang
- Department of Gastrointestinal Surgery, the Affiliated Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing 102218, China
| | - H Cao
- Department of General Surgery, General Hospital of Oriental Hospital Group, Huainan, Anhui 232001, China
| | - S C Wang
- Department of General Surgery, the 901th Hospital of PLA Joint Logistic Support Force, Hefei, Anhui 230031, China
| | - G Han
- Department of Gastrointestinal Surgery, the Second Hospital of Jilin University, Changchun, Jilin 130000, China
| | - D R Wang
- Department of General Surgery, Subei People's Hospital, Yangzhou, Jiangsu 225001, China
| | - H Wang
- Department of General Surgery, Dongying People's Hospital, Dongying, Shandong 257091, China
| | - J Zhang
- Department of General Surgery, FAW General Hospital, Changchun, Jilin 100191, China
| | - H Zhang
- Department of General Surgery, Dongguan Kanghua Hospital, Dongguan, Guangdong 523080, China
| | - D M Zhang
- Department of General Surgery, Baotou Central Hospital, Baotou, Inmer Mongolia 014040, China
| | - W S Liao
- Department of General Surgery, Traditional Chinese Medicine Hospital of Langxi County, Xuancheng, Anhui 242000, China
| | - W W Zhao
- Department of General Surgery, Xishan People's Hospital, Wuxi, Jiangsu 214100, China
| | - W Li
- Department of General Surgery, Xuzhou First People's Hospital, Xuzhou, Jiangsu 221002, China
| | - P Cui
- Department of General Surgery, Heji Hospital Affiliated to Changzhi Medical College, Changzhi, Shanxi 140400, China
| | - X Chen
- Department of General Surgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116023, China
| | - H Y Zhang
- Department of General Surgery, Nanyang Central Hospital, Nanyang, Henan 476000, China
| | - T Yang
- Department of General Surgery, Tianjin First Central Hospital, Tianjin 300192, China
| | - L Wang
- Department of General Surgery, the 900th Hospital of the PLA, Fuzhou, Fujian 350000, China
| | - Y S Gao
- Department of Gastrointestinal Surgery,the First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| | - J Li
- Department of Hepatobiliary Surgery, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, China
| | - J J Wu
- Department of General Surgery, Liyang People's Hospital, Liyang, Jiangsu 213300, China
| | - W Zhou
- Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310020, China
| | - Z J Lyu
- Department of Gastrointestinal Surgery, Guangdong Provincial People's Hospital, Guangzhou, Guangdong 510030, China
| | - J Fang
- Department of General Surgery, the First People's Hospital, Zhangjiagang, Jiangsu 100191, China
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8
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Gottardi L, van Weers H, Dercksen J, Akamatsu H, Bruijn MP, Gao JR, Jackson B, Khosropanah P, van der Kuur J, Ravensberg K, Ridder ML. A six-degree-of-freedom micro-vibration acoustic isolator for low-temperature radiation detectors based on superconducting transition-edge sensors. Rev Sci Instrum 2019; 90:055107. [PMID: 31153243 DOI: 10.1063/1.5088364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 04/18/2019] [Indexed: 06/09/2023]
Abstract
Dilution and adiabatic demagnetization refrigerators based on pulse tube cryocoolers are nowadays used in many low temperature physics experiments, such as atomic force and scanning tunneling microscopy, quantum computing, radiation detectors, and many others. A pulse tube refrigerator greatly simplifies the laboratory activities being a cryogen-free system. The major disadvantage of a pulse tube cooler is the high level of mechanical vibrations at the warm and cold interfaces that could substantially affect the performance of very sensitive cryogenic instruments. In this paper, we describe the performance of a very simple mechanical attenuation system used to eliminate the pulse-tube-induced low frequency noise of the superconducting transition-edge sensors under development for the instruments of the next generation of infra-red and X-ray space observatories.
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Affiliation(s)
- L Gottardi
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - H van Weers
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J Dercksen
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - H Akamatsu
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M P Bruijn
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J R Gao
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - B Jackson
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
| | - P Khosropanah
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - J van der Kuur
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
| | - K Ravensberg
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - M L Ridder
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
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9
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Mirzaei B, Silva JRG, Hayton D, Groppi C, Kao TY, Hu Q, Reno JL, Gao JR. 8-beam local oscillator array at 4.7 THz generated by a phase grating and a quantum cascade laser. Opt Express 2017; 25:29587-29596. [PMID: 29220996 DOI: 10.1364/oe.25.029587] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/16/2017] [Indexed: 06/07/2023]
Abstract
We present an 8-beam local oscillator (LO) for the astronomically significant [OI] line at 4.7 THz. The beams are generated using a quantum cascade laser (QCL) in combination with a Fourier phase grating. The grating is fully characterized using a third order distributed feedback (DFB) QCL with a single mode emission at 4.7 THz as the input. The measured diffraction efficiency of 74.3% is in an excellent agreement with the calculated result of 75.4% using a 3D simulation. We show that the power distribution among the diffracted beams is uniform enough for pumping an array receiver. To validate the grating bandwidth, we apply a far-infrared (FIR) gas laser emission at 5.3 THz as the input and find a very similar performance in terms of efficiency, power distribution, and spatial configuration of the diffracted beams. Both results represent the highest operating frequencies of THz phase gratings reported in the literature. By injecting one of the eight diffracted 4.7 THz beams into a superconducting hot electron bolometer (HEB) mixer, we find that the coupled power, taking the optical loss into account, is in consistency with the QCL power value.
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10
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Zhang J, Wang JJ, Yang RG, Liu K, Gao JR. Large-scale continuous-variable dual-rail cluster entangled state based on spatial mode comb. Opt Express 2017; 25:27172-27181. [PMID: 29092196 DOI: 10.1364/oe.25.027172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/11/2017] [Indexed: 06/07/2023]
Abstract
In recent continuous-variable (CV) multipartite entanglement researches, the number of fully inseparable light modes has been increased dramatically by the introduction of a multiplexing scheme in either the time domain or the frequency domain. In this paper, we propose a scheme that a large-scale (≥ 20) CV dual-rail cluster entangled state is established based on a spatial mode comb in a self-imaging optical parametric oscillator, which is pumped by two spatial Laguerre-Gaussian modes with different polarization and identical frequency. A sufficient condition of full inseparability for a CV dual-rail cluster entangled state is used to evaluate the degree of quantum entanglement. It is shown that entanglement exists over a wide range of analyzing frequency and pump parameter. We have found a new scheme that uses the optical parametric cavity to generate a large-scale entanglement based on optical spatial mode comb. The presented system will be hopefully as a practical entangled source for quantum information.
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11
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Mirzaei B, Silva JRG, Luo YC, Liu XX, Wei L, Hayton DJ, Gao JR, Groppi C. Efficiency of multi-beam Fourier phase gratings at 1.4 THz. Opt Express 2017; 25:6581-6588. [PMID: 28381005 DOI: 10.1364/oe.25.006581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We compare the results of simulated and measured power efficiency and far-field beam pattern, for two reflective Fourier phase gratings, designed to generate 2 × 2 and 2 × 4 beams respectively from a single-beam, coherent source at 1.4 THz. The designed surface structures were manufactured on aluminum plates by a computer numerical control (CNC) micro-milling machine. Despite small differences between the designed and fabricated gratings, we measured power efficiencies of both gratings to be around 70%, which is in a good agreement with the simulated values. We also find a good agreement between the simulated and measured diffracted beam size and spatial distribution. We demonstrate the application of both gratings as multiple beam local oscillators to simultaneously pump (or operate) a 4-pixel array of superconducting heterodyne mixers.
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12
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Yang RG, Zhang J, Zhai ZH, Zhai SQ, Liu K, Gao JR. Scheme for efficient extraction of low-frequency signal beyond the quantum limit by frequency-shift detection. Opt Express 2015; 23:21323-21333. [PMID: 26367980 DOI: 10.1364/oe.23.021323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Low-frequency (Hz~kHz) squeezing is very important in many schemes of quantum precision measurement. But it is more difficult than that at megahertz-frequency because of the introduction of laser low-frequency technical noise. In this paper, we propose a scheme to obtain a low-frequency signal beyond the quantum limit from the frequency comb in a non-degenerate frequency and degenerate polarization optical parametric amplifier (NOPA) operating below threshold with type I phase matching by frequency-shift detection. Low-frequency squeezing immune to laser technical noise is obtained by a detection system with a local beam of two-frequency intense laser. Furthermore, the low-frequency squeezing can be used for phase measurement in Mach-Zehnder interferometer, and the signal-to-noise ratio (SNR) can be enhanced greatly.
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13
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Zhang R, Zhang F, Liu FC, Yin FJ, Ding YJ, Gao JR, Chen J, Shao W. [History of heavy metal pollution from tidal flat in Haizhou Bay]. Huan Jing Ke Xue 2013; 34:1044-1054. [PMID: 23745413] [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] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Coastal zone could be considered as an important sink of regional source to sink and preserve historical records of environmental evolution. Four sediment cores, collected from tidal flat at Haizhou Bay near Lianyungang City, were examined for concentrations of heavy metals including Cd, Cr, Cu, Mn, Pb and Zn in core sediments to investigate the historical input of trace metals. In addition, sediment rates of cores LH3 and LH4 were determined based on radionuclide 210Pb. The results showed that grain size control effect was not the main factor that influenced the distribution of heavy metals. Heavy metals concentrations in the surface sediments were higher than these regional background values. Furthermore, Al element as a proxy of grain size was selected for normalization and calculation of metal enrichment factor (EF) and anthropogenic heavy metal fluxes. The results revealed that heavy metals in tidal flats were continuously enriched in the past decades, meanwhile, tidal flats have been significantly subjected to contaminations due to anthropogenic activities. Moreover, the depth profiles of heavy metals fluxes correspond to scenario of social-economy development of Lianyungang, which is an important urban area near Haizhou Bay. From 1950s to 2005, anthropogenic fluxes of metals increased with fluctuations, whereas, since 2005 anthropogenic fluxes declined, which may be correlated to the adjustment of industrial structure as well as the strengthened environmental regulation.
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Affiliation(s)
- Rui Zhang
- Department of Marine Technology, School of Geodesy and Geomatics Engineering, Huaihai Institute of Technology, Lianyungang 222005, China.
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14
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Abstract
We demonstrate for the first time that the Hartmann wavefront sensor (HWS) principle can be applied for characterizing the wavefronts of terahertz (THz) electromagnetic radiation. The THz Hartmann wavefront sensor consists of a metallic plate with an array of holes and a two-dimensional scanable pyro-electric detector. The THz radiation with different wavefronts was generated by a far-infrared gas laser operated at 2.5 THz in combination with a number of objects that result in known wavefronts. To measure the wavefront, a beam passing through an array of holes generates intensity spots, for which the positions of the individual spot centroids are measured and compared with reference positions. The reconstructed wavefronts are in good agreement with the model expectations.
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Affiliation(s)
- M Cui
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands.
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15
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Abstract
Myopia is a significant public health problem and its prevalence is increasing over time and genetic factors in disease development are important. The prevalence and incidence of myopia within sampled population often varies with age, country, sex, race, ethnicity, occupation, environment, and other factors. Myopia growth is under a combination of genes and their products in time and space to complete the coordination role of the guidance. Myopia-related genes include about 70 genetic loci to which primary myopias have been mapped, although the number is constantly increasing and depends to some extent on definition. Of these, several are associated with additional abnormalities, mostly as part of developmental syndromes. These tend to result from mutations in genes encoding transcriptional activators, and most of these have been identified by sequencing candidate genes in patients with developmental anomalies. Currently, COL1A1 (collagen alpha-1 chain of type I), COL2A1 (collagen alpha-1 chain of type II), ACTC1 (actin, alpha, cardiac muscle 1), PAX6 (paired box gene 6) and NIPBL (nipped-B homolog), and so on have been mapped. Myopia is most commonly treated with spectacles or glasses. The most common surgical procedure performed to correct myopia is laser in situ keratomileusis (LASIK). This review of the recent advances on epidemiology, genetic locations and treatments of myopia are summarized.
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Affiliation(s)
- Lei Yu
- Department of Ophthalmology, Xi'an Fourth Municipal People's Hospital, Xi'an 710004, Shaanxi Province, China
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16
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Khosropanah P, Baryshev A, Zhang W, Jellema W, Hovenier JN, Gao JR, Klapwijk TM, Paveliev DG, Williams BS, Kumar S, Hu Q, Reno JL, Klein B, Hesler JL. Phase locking of a 2.7 THz quantum cascade laser to a microwave reference. Opt Lett 2009; 34:2958-2960. [PMID: 19794781 DOI: 10.1364/ol.34.002958] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We demonstrate the phase locking of a 2.7 THz metal-metal waveguide quantum cascade laser (QCL) to an external microwave signal. The reference is the 15th harmonic, generated by a semiconductor superlattice nonlinear device, of a signal at 182 GHz, which itself is generated by a multiplier chain (x12) from a microwave synthesizer at approximately 15 GHz. Both laser and reference radiations are coupled into a bolometer mixer, resulting in a beat signal, which is fed into a phase-lock loop. The spectral analysis of the beat signal confirms that the QCL is phase locked. This result opens the possibility to extend heterodyne interferometers into the far-infrared range.
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Affiliation(s)
- P Khosropanah
- SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
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17
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Barends R, Baselmans JJA, Yates SJC, Gao JR, Hovenier JN, Klapwijk TM. Quasiparticle relaxation in optically excited high-Q superconducting resonators. Phys Rev Lett 2008; 100:257002. [PMID: 18643694 DOI: 10.1103/physrevlett.100.257002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Indexed: 05/26/2023]
Abstract
The quasiparticle relaxation time in superconducting films has been measured as a function of temperature using the response of the complex conductivity to photon flux. For tantalum and aluminum, chosen for their difference in electron-phonon coupling strength, we find that at high temperatures the relaxation time increases with decreasing temperature, as expected for electron-phonon interaction. At low temperatures we find in both superconducting materials a saturation of the relaxation time, suggesting the presence of a second relaxation channel not due to electron-phonon interaction.
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Affiliation(s)
- R Barends
- Kavli Institute of NanoScience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
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18
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Hajenius M, Khosropanah P, Hovenier JN, Gao JR, Klapwijk TM, Barbieri S, Dhillon S, Filloux P, Sirtori C, Ritchie DA, Beere HE. Surface plasmon quantum cascade lasers as terahertz local oscillators. Opt Lett 2008; 33:312-314. [PMID: 18278094 DOI: 10.1364/ol.33.000312] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We characterize a heterodyne receiver based on a surface-plasmon waveguide quantum cascade laser (QCL) emitting at 2.84 THz as a local oscillator, and an NbN hot electron bolometer as a mixer. We find that the envelope of the far-field pattern of the QCL is diffraction-limited and superimposed onto interference fringes, which are similar to those found in narrow double-metal waveguide QCLs. Compared to the latter, a more directional beam allows for better coupling of the radiation power to the mixer. We obtain a receiver noise temperature of 1050 K when the mixer is at 2 K, which, to our knowledge, is the highest sensitivity reported at frequencies beyond 2.5 THz.
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Affiliation(s)
- M Hajenius
- Kavli Institute of NanoScience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ, Delft, The Netherlands
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19
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Yang XJ, Liu J, Ye L, Liao QJ, Wu JG, Gao JR, She YL, Wu ZH, Ye LB. HCV NS2 protein inhibits cell proliferation and induces cell cycle arrest in the S-phase in mammalian cells through down-regulation of cyclin A expression. Virus Res 2006; 121:134-43. [PMID: 16797769 DOI: 10.1016/j.virusres.2006.02.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2005] [Revised: 01/28/2006] [Accepted: 02/07/2006] [Indexed: 11/29/2022]
Abstract
Chronic hepatitis C virus (HCV) infection often leads to liver cancer. NS2 protein is a HCV hydrophobic transmembrane protein that associates with several cellular proteins in mammalian cells. In this report, we investigated the functions of NS2 protein by examining its effects on cell growth and cell cycle progression. Stable NS2-expressing HeLa and Vero cell lines were established by transfection of the cells with pcDNA3.1(-)-NS2 followed by selection of the transfected cells in the presence of G418. We found that the proliferation rates of both NS2-expressing cell lines were inhibited by 40-50% compared with the control cells that were transfected with pcDNA3.1(-) control vector. Cell cycle analysis of these NS2-expressing cell lines shows that the proportion of cells in the S-phase increased significantly compared to that of control cells that do not express NS2 protein, suggesting NS2 protein induces cell cycle arrest in the S-phase. Further studies showed that the induction of cell cycle arrest in the S-phase by NS2 protein is associated with the decrease of cyclin A level. In contrast, the expression of NS2 protein does not affect the levels of cyclin-dependent kinase CDK2, CDK4, cyclin D1, or cyclin E. Our results suggest that HCV NS2 protein inhibits cell growth and induces the cell cycle arrest in the S-phase through down-regulation of cyclin A expression, which may be beneficial to HCV viral replication. Our findings not only provide information in the understanding mechanism of HCV infection, but also provide guidance for the future development of potential therapeutics for the prevention and treatment of the viral infection.
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Affiliation(s)
- Xiao-Jun Yang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, Hubei, PR China
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20
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Orlova EE, Hovenier JN, Klaassen TO, Kasalynas I, Adam AJL, Gao JR, Klapwijk TM, Williams BS, Kumar S, Hu Q, Reno JL. Antenna model for wire lasers. Phys Rev Lett 2006; 96:173904. [PMID: 16712299 DOI: 10.1103/physrevlett.96.173904] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Indexed: 05/09/2023]
Abstract
An antenna model is proposed for long (L >> A) lasers with subwavelength cross sections (wire lasers). It is shown that the far-field pattern of the wire lasers is determined by the ratio of the wavelength to the length. The radiation of the wire laser is predicted to be concentrated in a narrow beam theta approximately radical(2lambda/L) for laser modes where the longitudinal phase velocity is in synchronism with the velocity of light in air. Experimental results obtained using a terahertz quantum cascade wire laser are in agreement with the model.
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Affiliation(s)
- E E Orlova
- Institute for Physics of Microstructures, Russian Academy of Sciences, Nishny Novgorod GSP-105.
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21
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Yang XJ, Liu J, Ye LB, Yang F, Ye L, Gao JR, Wu ZH. In vitro and in vivo protective effects of proteoglycan isolated from mycelia of Ganoderma lucidum on carbon tetrachloride-induced liver injury. World J Gastroenterol 2006; 12:1379-85. [PMID: 16552805 PMCID: PMC4124314 DOI: 10.3748/wjg.v12.i9.1379] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the possible mechanism of the protective effects of a bioactive fraction, Ganoderma lucidum proteoglycan (GLPG) isolated from Ganoderma lucidum mycelia, against carbon tetrachloride-induced liver injury.
METHODS: A liver injury model was induced by carbon tetrachloride. Cytotoxicity was measured by MTT assay. The activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined with an automatic multifunction-biochemical analyzer and the levels of superoxide dismutase (SOD) and TNF-α were determined following the instructions of SOD kit and TNF radioimmunoassay kit. Liver sections were stained with hematoxylin and eosin (H&E) for histological evaluation and examined under light microscope.
RESULTS: We found that GLPG can alleviate the L-02 liver cells injury induced by carbon tetrachloride (CCl4) through the measurements of ALT and AST activities and the administration of GLPG to L-02 cells did not display any toxicity. Furthermore, histological analysis of mice liver injury induced by CCl4 with or without GLPG pretreatment indicated that GLPG can significantly suppress the toxicity induced by CCl4 in mice liver. We also found that GLPG reduced TNF-α level induced by CCl4 in the plasma of mice, whereas increased SOD activity in the rat serum.
CONCLUSION: GLPG has hepatic protective activity against CCl4-induced injury both in vitro and in vivo. The possible anti-hepatotoxic mechanisms may be related to the suppression of TNF-α level and the free radical scavenging activity.
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Affiliation(s)
- Xiao-Jun Yang
- College of Life Sciences, Wuhan University, Wuhan 430072, Hubei Province, China
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22
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Han X, Ye LB, Li BZ, She YL, Ye L, Zheng H, Gao B, Gao JR, Wu ZH. [The purification of HBV full-length PreS protein in Pichia pastoris]. Sheng Wu Gong Cheng Xue Bao 2005; 21:708-12. [PMID: 16285509] [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] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The Pichia pastoris strain GS115-PreS could produce a high expression level of full-length PreS protein that secreted to the supernatant after methanol induction in the fermentation. The Western blot analysis showed a single band with expected molecular mass of 48kD and that the major component of the particles was the full-length PreS protein (PreS1 + PreS2 + S) and small envelope protein (S) of 48 and 28 kD, respectively. Electron microscopy image showed PreS particles with 30 nm in diameter. The supernatants of the fermentation were desalted and concentrated. Purified PreS protein was obtained by DEAE-SFF anion exchange column chromatography and the PreS particles were obtained by ultracentrifugation and sucrose density gradient. The ELISA assay results proved that both full-length PreS protein and particles showed high immunogenicity and specificity. P/N ratio further demonstrated that the immunogenicity of the particles is higher than the full-length PreS protein.
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Affiliation(s)
- Xue Han
- National Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
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Gao JR, Zhu KY. An acetylcholinesterase purified from the greenbug (Schizaphis graminum) with some unique enzymological and pharmacological characteristics. Insect Biochem Mol Biol 2001; 31:1095-1104. [PMID: 11520688 DOI: 10.1016/s0965-1748(01)00057-1] [Citation(s) in RCA: 12] [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: 05/23/2023]
Abstract
An acetylcholinesterase (AChE, EC 3.1.1.7) was purified from the greenbug, Schizaphis graminum (Rondani). The maximum velocities (Vmax) for hydrolyzing acetylthiocholine (ATC), acetyl-(beta-methyl) thiocholine (AbetaMTC), propionylthiocholine, and S-butyrylthiocholine were 78.0, 67.0, 37.4, and 2.3 micromol/min/mg, and the Michaelis constants (Km) were 57.6, 60.6, 31.3, and 33.4 microM, respectively. More than 98% of AChE activity was inhibited by 10 microM eserine or BW284C51, but only 7% of the activity was inhibited by ethopropazine at the same concentration. Based on the substrate and inhibitor specificities, the purified enzyme appeared to be a true AChE. Nondenaturing polyacrylamide gel electrophoresis (PAGE) and isoelectric focusing of the purified AChE revealed three molecular forms. The isoelectric points were 7.3 for the major form and 6.3 and 7.1 for two minor forms. The major form of purified AChE showed molecular masses of 129 kDa for its native protein and 72 kDa for its subunits on SDS-PAGE. However, the purified AChE exhibited some distinctive characteristics including: (1) lack of affinity to the affinity ligand 3-(carboxyphenyl) ethyldimethyl ammonium, which has been used widely in purification of AChE from various insect species; and (2) 20-200-fold higher substrate-inhibition thresholds for ATC and AbetaMTC than AChE from other insect species. These biochemical properties may reflect structural differences of AChE purified from the greenbug compared with that from other insect species.
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Affiliation(s)
- J R Gao
- Department of Entomology, 123 Waters Hall, Kansas State University, Manhattan, KS 66506, USA
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24
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Gao JR, Zhu KY. Comparative toxicity of selected organophosphate insecticides against resistant and susceptible clones of the greenbug, Schizaphis graminum (Homoptera: aphididae). J Agric Food Chem 2000; 48:4717-4722. [PMID: 11052723 DOI: 10.1021/jf000548p] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Comparative toxicity of selected organophosphate (OP) insecticides against resistant and susceptible clones of the greenbug, Schizaphis graminum, were studied both in vitro and in vivo. Two resistant (OR-1 and OR-2) clones of the greenbug showed marginal to high levels of resistance to all seven OPs tested, ranging from 11- to 327-fold greater than those of a susceptible (OSS) clone. The OR-1 clone showed lower levels of resistance to phenyl (parathion and parathion-methyl) and heterocyclic (chlorpyrifos) OPs than to aliphatic OPs (dimethoate, omethoate, disulfoton, and demeton-S-methyl), whereas the OR-2 clone showed a rather broad spectrum of resistance to nearly all OP insecticides examined. In vitro inhibition of acetylcholinesterase (AChE) using six selected OP oxon analogues showed that alterations of AChE were involved in resistance to all OP compounds examined in both the OR-1 and OR-2 clones. Although the levels of insensitivity of AChE to these OPs were relatively low, ranging from 1.1- to 3.8-fold, the insensitivity spectrum of AChE to different OPs was rather broad. The general esterase activity in the OR-1 and OR-2 clones was 1.3-8. 4-fold higher than that in the OSS clone, depending on the substrates used. The AChE activity in both the OR-1 and OR-2 clones was 1.8-fold higher than that in the OSS clone. High resistance levels of the OR-2 clone to phenyl and heterocyclic OPs appeared to be associated with the ability of the esterases to hydrolyze beta-naphthyl acetate and more hydrophobic substrates.
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Affiliation(s)
- J R Gao
- Department of Entomology, 123 Waters Hall, Kansas State University, Manhattan, Kansas 66506, USA
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25
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Gao JR, Rao JV, Wilde GE, Zhu KY. Purification and kinetic analysis of acetylcholinesterase from western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae). Arch Insect Biochem Physiol 1998; 39:118-125. [PMID: 9880902 DOI: 10.1002/(sici)1520-6327(1998)39:3<118::aid-arch4>3.0.co;2-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Acetylcholinesterase (AChE, EC 3.1.1.7) was purified from western corn rootworm (WCR, Diabrotica virgifera virgifera) beetles by affinity chromatography. The purification factor reached over 20,000-fold with a specific activity of 169.5 mumol/min/mg and a yield of 23%. The Vmax values for hydrolyzing acetylthiocholine (ATC), acetyl-(beta-methyl) thiocholine (A beta MTC), propionylthiocholine (PTC), and S-butyrylthiocholine (BTC) were 184.8, 140.5, 150.2, and 18.8 mumol/min/mg, respectively, and K(m) values were 19.7, 18.5, 14.1, and 11.0 microM, respectively. The first three substrates showed significant inhibition to the AChE at higher concentrations, whereas BTC showed inhibition at the concentrations of 0.25-2 nM but activation at > 4 mM. AChE activity was almost completely inhibited by 1 microM eserine and BW284C15, respectively, but only 12% of AChE activity were inhibited by ethopropazine at the same concentration. These results suggested that the purified AChE from WCR was a typical insect AChE. Insecticides or their oxidative metabolites, chlorpyrifos-methyl oxon, carbofuran, carbaryl, malaoxon, and paraoxon, used in in vitro kinetic study exhibited high inhibition to AChE purified from WCR. However, chlorpyrifos-methyl oxon and carbofuran showed at least 36- and 4-fold, respectively, higher inhibitory potency than the remaining insecticides examined. Results from our in vitro inhibition of AChE agreed quite well with the previously published in vivo bioassay data.
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Affiliation(s)
- J R Gao
- Department of Entomology, Kansas State University, Manhattan 66506, USA
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26
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Zhang Q, Hu YL, Guo JY, Gao JR, Gao Y. [Study on the individual sensitivity to some tumors and their related biological markers in residents in Guangdong Province]. Zhonghua Liu Xing Bing Xue Za Zhi 1997; 18:379-80. [PMID: 9812549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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27
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Gao JR, Liu HX, Xu SZ. [Carrying out standardized management, improving nursing quality]. Zhonghua Hu Li Za Zhi 1996; 31:88-90. [PMID: 8716756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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28
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Gao JR, Schüssler AS, Caro J, Radelaar S, Heyers K. Lateral-superlattice effect on weak localization in silicon inversion layers. Phys Rev B Condens Matter 1992; 46:9885-9888. [PMID: 10002820 DOI: 10.1103/physrevb.46.9885] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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29
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Gao JR, Caro J, Radelaar S, Offenberg M, Lauer V, Singleton J, Janssen TJ, Perenboom JA. One-dimensional subband effects in the conductance of multiple quantum wires in Si metal-oxide-semiconductor field-effect transistors. Phys Rev B Condens Matter 1990; 41:12315-12318. [PMID: 9993697 DOI: 10.1103/physrevb.41.12315] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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30
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Gao JR, Caro J, Verbruggen AH, Radelaar S, Middelhoek J. Temperature dependence of universal conductance fluctuations in narrow mesoscopic Si inversion layers. Phys Rev B Condens Matter 1989; 40:11676-11682. [PMID: 9991770 DOI: 10.1103/physrevb.40.11676] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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31
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Gao JR. [Screening of temperature-sensitive mutants of Bacillus thuringiensis phages and the identification of its character]. Wei Sheng Wu Xue Bao 1988; 28:91-2. [PMID: 3388831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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32
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Gao JR. [Isolation and purification of mumps virus nucleocapsid and calculation of its RNA molecular weight]. Wei Sheng Wu Xue Bao 1988; 28:93-5. [PMID: 3388832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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33
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Gao JR, Hung LS, Chiang S, Ku KY. Detergent, Brij, increasing the area of new surface membrane during the early cleavage of eggs of Rana amurensis. Cell Biol Int Rep 1986; 10:969-77. [PMID: 3802217 DOI: 10.1016/0309-1651(86)90118-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The exposure of new surface membrane occurred in the cleavage furrow of Rana amurensis eggs enclosed in fertilization membrane immersed in Brij solution. The exposed area increased gradually and reached a maximum while the furrow extended to 240 degrees around the egg surface. At this time, the new membrane area of the treated eggs was significantly larger than that of the control. Afterwards, the exposed new membrane area decreased gradually. This may result from the extent of new membrane increase being less than the extent of contraction of cleavage furrow.
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