[Summer Ozone Mechanism and Control Strategy in Beijing-Tianjin-Hebei Region Using Brute-Force Method]

In recent years, the ozone (O3) volume fraction in the Beijing-Tianjin-Hebei Region in summer have remained high, light to moderate pollution occurs frequently, and research on related response mechanisms is urgently needed. This study applied the WRF-Chem model to simulate the change in ozone volume fraction in this region by setting 13 precursor emission scenarios in a representative month in the summer of 2018. The results revealed that VOC-sensitivity and no-sensitivity regimes commonly occurred in the Beijing-Tianjin-Hebei Region in July, and the VOC-sensitivity regimes were mainly accumulated in the central Beijing-Tianjin-Hebei Region, with a north-to-south zonal distribution and an area share of 15.60%-26.59%. The relative response intensity (RRI) of O3 volume fraction to precursor emissions in urban areas had large spatial variability, with RRI_VOC and RRI_NOx in the ranges of 0.03-0.16 and -0.40-0.03, respectively. The higher the latitude of urban areas, the more dramatic were the RRI values, indicating a more significant regional transport influence. The lower RRI_NOx values in urban areas with high intensity of precursor emissions implied a negative dependence of RRI_NOx on local NO2 concentrations; however, RRI_VOC was not significantly correlated with NO2levels and was more dependent on the relative abundance of precursors (VOCs:NOx). The ratio of RRI_VOC to RRI_NOx showed negative values in majority of the cities; therefore, collaborative VOCs emission reduction is necessary to suppress the deterioration of O3 volume fraction. The absolute value of this ratio was much lower in cities with high industrialization and urbanization than in ordinary small and medium-sized cities, implying that the demand for collaborative VOCs emission reduction in these cities will be higher. However, even under 50% reduction of precursors, the improvement in O3 volume fraction was limited in regional cities, and the combined prevention in neighboring cities remains important.

[Difference in PM2.5 Pollution and Transport Characteristics Between Urban and Suburban Areas]

Based on multi-source observation data, such as lidar ceilometer, aircraft AMDAR, and conventional sites, combined with numerical simulation (CAMx-PSAT), this study took the typical cities of the Beijing-Tianjin-Hebei region-Beijing (BJ) urban area and suburbs (Miyun) and Shijiazhuang (SJZ) urban area and suburbs (Pingshan) as the case study areas. The differences in boundary layer height between urban areas and suburbs (ΔPBLH), surface PM_2.5 mass concentration (ΔSurf_PM_2.5), vertical PM_2.5 mass concentration (ΔVert_PM_2.5), and transmission flux intensity and height distribution characteristics were analyzed. The results showed:due to factors such as anthropogenic heat sources, short-wave radiation, and thermal turbulence, the annual average planetary boundary layer height in urban areas was 8%-29% higher than that in the suburbs, and in different seasons, the monthly average planetary boundary layer height in urban areas was 2% (April in SJZ)-47% (July in BJ) higher than that in the suburbs. Due to the combined effects of anthropogenic emissions, inversions, and atmospheric turbulence, the annual averageρ(PM_2.5) in urban areas between 0-1260 m was higher than that in suburbs by 0.1 (SJZ)-29.7 (BJ) μg·m^-3 and decreased with the increase in height. The annual average total net flux intensity in urban areas was much greater than that in suburbs, with outflows in urban areas and inflows in suburbs; due to the urban low pressure and the suburban high pressure, suburban thermal circulation was formed. The annual average total net flux intensity in BJ (44.77 t·d^-1) was greater than that in SJZ (34.44 t·d^-1). Affected by wind speed and PM_2.5 mass concentration, between 0-1260 m, the fluxes in urban areas and suburbs and surrounding areas showed an obvious trend of increasing net flux intensity with the increase in height above the ground. Furthermore, the transmission exchange between urban areas and suburbs and surrounding areas in January and April had the most obvious impact on the environment. The intensity of the maximum net flux in the lower urban areas and the suburbs in different seasons was significantly different, and the difference between the two was 2.23-4.48 times; however, the height characteristic difference in the intensity of the maximum net flux was small, mainly located at 611-1260 m.

[Effects of salivary microbiota on tryptophan-aryl hydrocarbon receptor signaling axis in mice with periodontitis]

Objective: To study the effects of salivary microbiota in patients with periodontitis on the tryptophan-aryl hydrocarbon receptor (AhR) signaling axis in mice with periodontitis and to provide theoretical basis as well as new ideas for the influences of periodontitis on systemic metabolism. Methods: Salivary microbiota of 12 healthy individuals and 14 patients with periodontitis were collected in Nanjing Stomatological Hospital, Medical School of Nanjing University from June to December of 2020. According to the random number table method, twenty-four mice were randomly divided into three groups: Sham group (control group), P group (periodontitis patients' salivary microbiota group) and H group (periodontal healthy individuals' salivary microbiota group). The maxillary second molars of all mice were treated with silk thread ligation to induce periodontitis. Phosphate buffer as well as salivary microbiota of periodontal healthy individuals and periodontitis patients were gavaged into periodontitis mice for 2 weeks. The expression of inflammatory factors in mice serum were detected by enzyme linked immunosorbent assay, and the expression of tryptophan and indole metabolites in intestinal tract and serum were detected by liquid chromatography-mass spectrometry. The expression of AhR in intestinal tract of mice was detected by immunohistochemistry and quantitative real time-PCR while gut microbiota constitution was detected by 16S rRNA gene sequencing. The remaining saliva samples of periodontitis patients and periodontal healthy individuals were applied to detect the expression of tryptophan and indole metabolites themselves. Results: The salivary microbiota of periodontitis patients could induce the expression of interleukin-1β [P group: (162.38±39.46) pg/ml, H group: (82.83±20.01) pg/ml; t=4.40, P=0.001) and tumor necrosis factor-α [P group: (361.16±123.90) pg/ml, H group: (191.66±106.87) pg/ml; t=2.54, P=0.030) in serum of periodontitis mice, and reduce the expression of AhR in colon (P group: 1.18±0.05, H group:1.83±0.47; t=3.09, P=0.015) and ileum (P group: 0.80±0.13, H group: 1.18±0.11; t=4.93, P=0.001). After gavage of salivary microbiota of periodontitis patients to the mice, tryptophan (P group: (18.1±3.8)×10⁷, H group: (26.6±6.6)×10⁷; t=2.49, P=0.037] and indole lactic acid [P group: (1.9±0.7)×10⁷, H group: (3.7±0.6)×10⁷; t=4.49, P=0.002) in serum of periodontitis mice were significantly decreased, but was relatively disorder in intestinal tract. However, the expressions of tryptophan and indole metabolites in saliva of periodontitis patients were higher than those of periodontal healthy individuals. There were significant differences in indole propionic acid [P group: (1 239.39±818.72) nmol/L, H group: (56.96±38.33) nmol/L; t=2.83, P=0.022]. What we find noteworthy was that the expressions of indolelactic acid metabolism in saliva, serum and intestinal were consistent, and salivary microbiota of periodontitis patients could reduce the relative abundance of indolelactic acid-producing bacteria in the gut, suggesting that the salivary microbiota of periodontitis patients might affect the expression of AhR through gut microbiota disorder and indolelactic acid downregulation. Conclusions: Salivary microbiota in patients with periodontitis may affect the systemic inflammatory state through down-regulating the expression of tryptophan-AhR signal axis.

[Applying Photochemical Indicators to Analyze Ozone Sensitivity in Handan]

Ozone pollution in Handan has become severe in recent years and in the summer of 2018, the average maximum daily 8-hour average ozone concentration in Handan was 175 μg·m^-3 with a maximum of 257 μg·m^-3. Ozone concentrations exceeded the National Air Quality Grade Ⅱ Standard in 59% of cases. In this study, the H₂O₂/HNO₃ indicator was applied to analyze summertime ozone sensitivity in Handan using the WRF-CMAQ modeling system. The results showed that H₂O₂/HNO₃ was more appropriate than other ozone indicators, both theoretically and based on simulation outputs. The good simulation effect of CMAQ on H₂O₂ and HNO₃ was attributed to fine emission inventory and grid resolution. The H₂O₂/HNO₃ simulation results showed that the relative importance of a VOCs-limited regime decreased month by month; a VOCs-NO_x-mixed-limited regime was dominant in June; and a NO_x-limited regime was more dominant in July and August than in June. The remarkable spatial difference in VOCs and NO_x emission ratios among the counties of Handan led to differences in ozone sensitivity. The VOCs-limited regime was concentrated in counties where VOCs/NO_x emission ratios were lower than 1.7. Southern counties had a NO_x-limited regime, where VOCs/NO_x emission ratios were higher than 6.9. Counties with VOCs/NO_x emission ratios varying from 1.7 to 6.9 were more susceptible to both VOCs and NO_x. According to these results, the transition range of HCHO/NO₂, O₃/HNO₃, and O₃/NO_x ratios were adjusted to 0.35-0.6, 20-35, and 10-25 respectively. Adjusting the transition range of H₂O₂/(O₃+NO₂) was not effective, indicating that this indicator may not be applicable to Handan.

[Multidimensional Verification of Anthropogenic VOCs Emissions Inventory Through Satellite Retrievals and Ground Observations]

In this paper, a regional emissions inventory of anthropogenic VOCs was established based on the traditional emissions factor method for the Beijing-Tianjin-Hebei (BTH) region, followed by a multidimensional calibration study based on regional satellite remote sensing information for formaldehyde and typical urban ground VOCs. Inventory calculations showed that the VOCs emissions in BTH in 2013, 2015, and 2017 were 2026700, 2073400, and 1934200 tons, respectively, comprising alkanes (29.83% to 30.72%), unsaturated hydrocarbons (16.54% to 17.68%), aromatic hydrocarbons (27.14% to 27.51%), aldehydes (8.75% to 9.52%), ketones (8.13% to 9.04%), and aldehydes and ketones lipids (5.13% to 6.60%). During 2013-2017, the emission of VOCs in Zhangjiakou, Qinhuangdao, and Hengshui increased slightly (1.10% to 1.66% per year); emissions in Xingtai and Handan decreased slightly (-1.46% to -1.12% per year); and emissions in Chengde, Tangshan, Baoding, and Cangzhou were stable. There trends were consistent with the inter-annual trend of satellite-derived HCHO column concentrations. However, in Beijing, Tianjin, Langfang, and Shijiazhuang, annual variations in VOCs emissions (-6.51%, -3.30%, 2.16%, and 0.11% per year) and HCHO column concentrations (-1.17%, 7.19%, -0.24%, and 6.68% per year) were observed, respectively. In the regional VOCs inventory, a good linear correlation (R>0.5) was achieved between the grid emissions of VOCs and HCHO column concentrations in urban areas, while the correlation was only 0.33 in suburban areas. This is mainly due to the important influence of secondary conversion of VOCs originating from natural sources to HCHO in suburban areas. In addition, ground-level VOCs concentrations were observed in the urban areas of Beijing and Handan, where the emission ratios (ERs) of VOCs and CO were regressed. The ERs of most hydrocarbons were in good agreement with the regressed ERs, but the ERs of ethane were significantly lower (-156% to -73%) and the ERs of aromatic hydrocarbons above C8 were relatively high (54% to 74%). In general, the regional anthropogenic VOCs emissions inventory established in this paper offers high accuracy and reliability.

Hydrophobic Interface Starch Nanofibrous Film for Food Packaging: From Bioinspired Design to Self-Cleaning Action

Starch-derived edible food films have great potential as biodegradable food packaging materials because they reduce the overuse of traditional petroleum-based plastic. Herein, we demonstrate a direct method of mass producing a pure starch food packaging film that consisted of starch nanofibers by using a temperature-assisted electrospinning technique without addition of any nonstarch components. To overcome the major issue of ultralow hydrophobicity of starch nanofibrous film (SNF), we used a facile and low-cost solution immersion approach to create a fiber coating of stearic acid (STA) inspired by biological organisms with superhydrophobic properties, such as lotus leaves. Hierarchical flower-like micronanostructures were obtained on SNF by controlled assembly of STA onto the surface of starch nanofibers. Benefiting from the effective formation of STA self-assembled lamella, the multiscale microstructure surface features, low surface energy, and enhancing thermal stability of SNF were obtained and confirmed to result in the variety of its hydrophobicity, which can be also tailored by simple controlling of the solution concentration of STA. Importantly, the STA-self-assembled coated SNF enabled water to roll freely in all directions, which is a crucial factor for self-cleaning. Our novel strategy based on self-assembly can guide development of bioinspired hydrophobic interfaces for starch-based films for edible hydrophobic materials.

Starch/tea polyphenols nanofibrous films for food packaging application: From facile construction to enhance mechanical, antioxidant and hydrophobic properties

Starch based food packaging has been receiving increasing attention. However, the inherent poor properties of starch restrict its practical applications in the versatile material science field. In this study, a fast, simple, and environmentally friendly route to construct polyfunctional starch/tea polyphenols nanofibrous films (STNFs) by one-step temperature-assisted electrospinning was developed. The effects of introduction of tea polyphenols (TP) on the mechanical and antioxidant activity of STNFs were comprehensively investigated. Results of ABTS·+ free radical scavenging assay showed that the antioxidant activity of STNFs was endowed by addition of TP with optimum mechanical properties confirmed by tensile test. More interestingly, the hydrophobicity of STNFs was improved dramatically with increasing cross-linking time as indicated by water contact angle (WCA) measurement showing no effect on the antioxidant activity of the films. The results of this work offer a major step forward to promote functional starch-based materials for sustainable application in food packaging.

[Current status and research progress of third-line treatment for patients with gastric cancer in China]

Gastric cancer (GC) is one of the most common malignant tumors in the world. The prognosis of advanced GC is extremely poor, characterized by the high recurrence or disease progression rate after the first-line chemotherapy, and the extremely low long-term survival rate. Meanwhile, the options for subsequent treatment are limited. Studies have shown that the third-line therapy can provide significant survival benefits for selected patients with advanced GC. Currently, a series of randomized controlled trials and real-world studies related to chemotherapy, targeted therapy, and immunotherapy are conducted. In addition, the explorations of combination therapy, and screening the optimal clinical features or predictive biomarkers for the suitable population who might benefit from the third-line regimens are the hot spots for researchers. This article will provide a detailed overview of the current status and progress of the third-line treatment for advanced GC, and to illustrate the characteristics of Chinese GC treatment.

Polysaccharide-Based Hydrogels Derived from Cellulose: The Architecture Change from Nanofibers to Hydrogels for a Putative Dual Function in Dye Wastewater Treatment

Agricultural production-caused water contamination has become an urgent environmental issue that has drawn much attention in recent years. One such contamination case is the environmental disposal of colored effluents from the food processing industry (i.e., food dyes). Effective methods for removing dye contaminants from water have been increasingly sought, and different adsorbents have been developed for this purpose. Here, polysaccharide-based hydrogels derived from cellulose were constructed and used in the removal of methylene blue (MB) (as the representative dye) from an aqueous medium (as simulated dye liquor wastewater). To improve the purification efficiency, TiO₂ nanoparticles were encapsulated into cellulose nanofibers, which were consequently changed to hydrogels with respective advantages. The morphology, chemical composition, and structure of the as-prepared polysaccharide-based hydrogels and the transformation process from nanofibers to hydrogels were revealed by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction, and the presence of a gel network structure and TiO₂ nanoparticles was confirmed. As expected, the polysaccharide-based hydrogels exhibited good MB removal performance because of their synergistic effects of absorption and photocatalytic degradation. Furthermore, the cell cytotoxicity test showed that the polysaccharide-based hydrogels possessed good biocompatibility. The facile, noncytotoxic, and general strategy presented here could be extended to the preparation of other polysaccharide-based hydrogel materials and has good prospects for application in wastewater treatment.

Screening and identification of miRNAs related to sexual differentiation of strobili in Ginkgo biloba by integration analysis of small RNA, RNA, and degradome sequencing

BACKGROUND

Ginkgo biloba, a typical dioecious plant, is a traditional medicinal plant widely planted. However, it has a long juvenile period, which severely affected the breeding and cultivation of superior ginkgo varieties.

RESULTS

In order to clarify the complex mechanism of sexual differentiation in G. biloba strobili. Here, a total of 3293 miRNAs were identified in buds and strobili of G. biloba, including 1085 known miRNAs and 2208 novel miRNAs using the three sequencing approaches of transcriptome, small RNA, and degradome. Comparative transcriptome analysis screened 4346 and 7087 differentially expressed genes (DEGs) in male buds (MB) _vs_ female buds (FB) and microstrobilus (MS) _vs_ ovulate strobilus (OS), respectively. A total of 6032 target genes were predicted for differentially expressed miRNA. The combined analysis of both small RNA and transcriptome datasets identified 51 miRNA-mRNA interaction pairs that may be involved in the process of G. biloba strobili sexual differentiation, of which 15 pairs were verified in the analysis of degradome sequencing.

CONCLUSIONS

The comprehensive analysis of the small RNA, RNA and degradome sequencing data in this study provided candidate genes and clarified the regulatory mechanism of sexual differentiation of G. biloba strobili from multiple perspectives.

[Comparison Analysis of the Effect of Emission Reduction Measures for Major Events and Heavy Air Pollution in the Capital]

Taking the "9.3" military parade in 2015 and two red alerts of heavy air pollution in December of the same year as examples, the characteristics of meteorological factors and pollutant concentration variation were compared. Based on the estimation of pollutant emission reduction under different periods, the WRF-CAMx model was used to evaluate the effect of PM_2.5 pollution improvement. The results showed that the daily average PM_2.5 concentration (19.0 μg·m^-3) during the parade (from August 20 to September 4) decreased by 60.0% and 48.0%, respectively, in comparison to that before (August 15-19) and after (September 5-15) the parade. The daily average PM_2.5 concentration (232.3 μg·m^-3) during the first red alert period was higher than that of the second red alert (216.6 μg·m^-3). The air quality before the second red alert was better than that before the first red alert. The proportion of emission reduction during the parade was generally larger than that during the red alert periods, which provided a controllable and favorable condition for the realization of the "Parade Blue". The PM_2.5 concentration in Beijing decreased by 32.4%, 17.1%, and 22.0% under the control measures during the periods of the "9.3" parade, the first red alert, and second red alert, respectively. The higher proportion of PM_2.5 concentration reduction could be attributed to the more intensive regional emission reduction and the favorable meteorological conditions. The intensity of the pollution reduction, the timing of the implementation of emergency control measures, and meteorological conditions were the most important factors that may have influenced the improvement of pollution.

Perioperative outcomes of women with and without class III obesity undergoing hysterectomy for endometrioid endometrial cancer: A population-based study

OBJECTIVE

Population-based data on perioperative complications among women with endometrial cancer and severe obesity are lacking. We evaluated 30-day complication rates among women with and without class III obesity (body mass index ≥ 40 kg/m²) undergoing primary surgical management for endometrioid endometrial cancer (EEC), and how outcomes differed according to surgical approach (open vs. minimally invasive).

METHODS

We performed a retrospective population-based cohort study of women with EEC undergoing hysterectomy in Ontario, Canada, between 2006 and 2015. We evaluated perioperative complications in the whole cohort, and in a 1:1 matched analysis using hard and propensity score matching to ensure similar distributions of patient, tumour, provider and institution-level factors between women with and without class III obesity (identified using a surgical billing code). The primary outcome of interest was the 30-day perioperative complication rate.

RESULTS

12,112 women met inclusion criteria; 2697 (22.3%) had class III obesity. We matched 2320 (86%) women with class III obesity to those without. The composite complication rate was significantly higher among women with class III obesity (23.2% vs. 18.4%, standardized mean difference [SMD] = 0.12), primarily due to wound infection/disruption (12.1% vs. 6.2%). There was no difference in outcomes for women with and without class III obesity when a minimally invasive approach was used.

CONCLUSIONS

Wound infection/disruption was increased for women with class III obesity compared to women without. Otherwise, perioperative complications were similar between the matched pairs. When minimally invasive approaches were used, women with class III obesity had a similar risk of complications as women without obesity.

Temperature and excitation wavelength dependence of circular and linear photogalvanic effect in a three dimensional topological insulator Bi2Se3

The circular (CPGE) and linear photogalvanic effect (LPGE) of a three-dimensional topological insulator Bi₂Se₃ thin film of seven quintuple layers excited by near-infrared (1064 nm) and mid-infrared (10.6 [Formula: see text]m) radiations have been investigated. The comparison of the CPGE current measured parallel and perpendicular to the incident plane, together with the comparison of the CPGE current under front and back illuminations, indicates that the CPGE under front illumination of 1064 nm light is dominated by the top surface states of the Bi₂Se₃ thin film. The CPGE current excited by 10.6 [Formula: see text]m light is about one order larger than that excited by 1064 nm light, which may be attributed to the smaller cancelation effect of the CPGE generated in the two-dimensional electron gas when excited by 10.6 [Formula: see text]m light. Under the excitation of 1064 nm light, the LPGE current is dominated by the component which shows an even parity of incident angles, while the LPGE current excited by 10.6 [Formula: see text]m light is mainly contributed by the component which is an odd parity of incident angles. Both of the CPGE and LPGE currents excited by 1064 nm decrease with increasing temperature, which may be owing to the decrease of the momentum relaxation time and the stronger electron-electron scattering with increasing temperature, respectively.

The generation of two specific cancer costing algorithms using Ontario administrative databases

Cancer treatment and management have become increasingly economically burdensome. Consequently, to help with planning health service delivery, it is vital to understand the associated costs. Administrative databases can be used to help understand and generate real-world system-level costs. Using databases to generate costs can take one of two approaches: top-down or bottom-up. Top-down approaches disaggregate the total health care spending from a global health care budget by sector and provider. A bottom-up approach begins with individual-level health care use and its costs, which are then aggregated.

[Concentration Characteristics of PM2.5 and the Causes of Heavy Air Pollution Events in Beijing During Autumn and Winter]

To study the changing of characteristics and formation mechanisms of PM_2.5 in Beijing during the last two years, particulate matter concentrations, weather conditions, and air-mass trajectories were analyzed during severe pollution episodes in fall and winter 2016-2017 using routine observations and the TrajStat model. Results showed that 13 heavy pollution events, each lasting at least two days, occurred in Beijing. Of these, approximately 61.5% occurred in winter, characterized by heavier pollution concentrations and longer durations than those occurring in autumn. A low-pressure gradient, high humidity, low surface wind speed, low boundary layer, and particular terrain (i. e., being surrounded by mountains on three sides) all contributed to the high occurrence frequency of severe pollution episodes in autumn and winter. During the pollution episodes, the average ratio of PM_2.5 to PM₁₀ reached 0.86. The air-masses during the accumulation stage were mainly transported from the northwest, west, southwest, and southeast of Beijing. The southwestern and southeastern transmission paths accounted for 21.6% of the total pollution load. In addition, the WRF-CAMx model was used to quantitatively analyze the contributions of local and external sources to the concentrations of PM_2.5 in Beijing during 16-22 December 2016. Based on this analysis, PM_2.5 contributions notably varied with different air-masses; in the case of southern air-masses, external sources dominated the PM_2.5 concentrations in Beijing and local contributions decreased rapidly; in contrast, in the case of northwestern air-masses, the opposite pattern occurred. Overall, the contribution of local sources to PM_2.5 concentrations in Beijing varied from 16.5% to 69.3% during the monitored pollution episodes.

[Characteristics of PM2.5 Pollution and the Efficiency of Concentration Control During a Red Alert in the Beijing-Tianjin-Hebei Region, 2016]

The Beijing-Tianjin-Hebei (BTH) region experienced a heavy pollution episode in December 2016. Beijing and Tianjin issued a red alert from 20:00 December 16 to 24:00 December 21, while every city in Hebei Province (except Zhangjiakou, Chengde, and Qinhuangdao) issued a red alert from 00:00 December 16 to 18:00 December 22. In order to study the process of heavy pollution and the effect of implementing emergency measures, pollutant concentrations, meteorological conditions, air mass transmission and region transmission, and control effects were analyzed based on environmental monitoring data and simulation. Mean PM_2.5 concentrations during the heavy pollution episode in each city all exceeded 200 μg·m^-3 and the peak value of hourly averaged concentration (834.5 μg·m^-3) occurred in Handan. The meteorological conditions during the heavy pollution episode restricted the diffusion of pollutants, with low pressure and air mass transmission exacerbating the problem. The mean fraction of PM_2.5 concentrations in local emissions was 47.1%, but this differed between cities due to variable meteorological conditions. The average reduction of PM_2.5 concentrations was 27.6%, indicating that the implementation of a red alert measure was effective. If the emergency measures had been implemented a few days earlier, a greater reduction ratio would have been achieved; a 4.4% greater average reduction in PM_2.5 concentrations would have occurred if the measures were implemented two days earlier, while taking action three or more days in advance would not have achieved significant improvement.

[Characteristics of VOCs Emitted from the Rubber Tire Manufacturing Industry Based on the Inverse-Dispersion Calculation Method]

This study selected a rubber tire manufacturing factory located in the North China Plain, and conducted ambient volatile organic compounds (VOCs) observation tests, and calculated the emission of VOCs based on the inverse-dispersion calculation method. The monitoring results found significant differences in both VOC concentrations and chemical composition between the up-wind (background) and the downwind receptors. The average concentrations of VOCs measured by the background and receptors were 53.8 μg·m^-3 and 127.5 μg·m^-3, respectively. Propane (7.2 μg·m^-3), cetone (7.5 μg·m^-3), nonanal (12.7 μg·m^-3), n-butane (4.9 μg·m^-3), and acetaldehyde (2.7 μg·m^-3) were the dominant components of background VOCs, and nonanal (43.5 μg·m^-3), propane (11.4 μg·m^-3), acetaldehyde (7.4 μg·m^-3), hexane (11.9 μg·m^-3), and n-butane (7.3 μg·m^-3) were the dominant components of receptor VOCs. The difference in VOCs between the background and receptors is considered to reflect contributions from the factory, the main components of which were of alkanes (31.39%) and oxygenated organic compounds (33.15%). Using the ISC3 model, the relation coefficient γ between the downwind VOCs increment and the emissions of the factory was calculated for each receptor of each test based on the hourly average meteorological conditions during the observation period. Combining the relation coefficient γ with the difference in VOCs between the receptor and the background, we calculated VOC emission amounts from this factory of 152.8±188.2 t·a^-1 and a VOC emission factor (EF) for the rubber tire manufacturing industry of VOC 101.9 g·tire^-1. Our estimated EF was loser to EF of U. S. AP42 (55 g·tire^-1), but greatly lower than the EF of China's reference (900 g·tire^-1). Although our calculations had a relatively higher standard deviation, these results are helpful for better understanding the emission of VOCs from the rubber manufacturing industry. Based on our calculated EF, China's national VOCs emissions from the rubber tire manufacturing industry would be approximately 62.13 kt·a^-1, which represents a significant potential contribution to ozone formation (130.87 kt·a^-1), but the organic aerosol formation potential is small (0.86 kt·a^-1).

[Pollution Characteristics and Regional Transport of Atmospheric Particulate Matter in Beijing from October to November, 2016]

In this study, the Aerosol Chemical Speciation Monitor (ACSM) was used to conduct real-time and continuous comprehensive observation of chemical components in non-refractory submicron aerosols (NR-PM₁) from October 15 to November 15, 2016. In addition to that, the evolution characteristics of NR-PM₁ chemical components were discussed. The potential source contribution function (PSCF) method and a meteorology-air quality coupling model system (WRF-CAMx) were applied to identify the potential PM_2.5 emission sources and transport path in Beijing, and the vertical distribution characteristics of PM_2.5 net transport flux. The results indicate that the monthly average mass concentrations of NR-PM₁ and PM_2.5 were (59.16±57.05) μg·m^-3 and (89.82±66.66) μg·m^-3, respectively. On average, NR-PM₁ accounted for (70.31±22.28)% of PM_2.5. During the whole study period, Org, NO₃^-, SO₄^2-, NH₄⁺, and Chl represented (42.75±11.35)%, (21.27±7.72)%, (19.11±7.08)%, (12.19±2.64)%, and (4.68±3.24)% of NR-PM₁, respectively. The diurnal variation characteristics of different chemical components were disparate. The high potential source areas were mainly located in southern Hebei, northeastern Henan, and western Shandong provinces during the whole study period. During the haze episode, the potential regions of higher contribution were concentrated in Baoding, southern Beijing, and Langfang. The simulation results of WRF-CAMx showed that the vertical distribution characteristics of PM_2.5 net flux varied with different altitudes. The adjacent cities mainly export PM_2.5 to Beijing, and the PM_2.5 net fluxes mainly occurred at 600-800 m during the whole study period. PM_2.5 in Beijing from external sources mainly occurred in high altitudes during the early stage of the heavy pollution episode. Then it turned to near-ground transport until November 5, when the pollution was the most severe. This indicated that high-altitude and near-ground transport both played an essential role in the formation of heavy PM_2.5 pollution in Beijing during the autumn. Moreover, two important transport pathways were identified:the southwest-northeast pathway (Baoding→Beijing→Chengde) and the northwest-southeast pathway (Zhangjiakou→Beijing→Langfang-south→Tianjin).

[Cause and Effect Evaluation of PM2.5 During Three Red Alerts in Beijing from 2015 to 2016]

Beijing authorities issued three red alerts for heavy air pollution at 6 pm on December 7 and 7 am on December 18, 2015, and at 1 pm on December 15, 2016, respectively. To better understand the different causes of the three red alerts and assess the effectiveness of emergency measures dealing with heavy air pollution, the PM_2.5 concentrations, meteorological conditions, weather conditions, and air mass transmission were analyzed during the red alerts using data from environmental and meteorological monitoring stations in Beijing. All three red alerts were affected by secondary transformation, but the high PM_2.5 concentrations were mainly affected by meteorological conditions. During the first and second red alerts, the ground in Beijing was controlled by a uniform pressure field and the regional transport was mainly affected by southwestern and southern air masses. During the third red alert, the ground was under the control of a wide range of low pressure and affected by the superposition of southwestern and local air masses. During the third red alert, the PM_2.5 pollution was the most serious. Its average concentration was the highest (273.6 μg·m^-3), that is, 1.2 times and 1.3 times higher than that of the previous two alerts, respectively. The WRF-CMAQ model was used in combination with the emission reduction of each source to evaluate the effects of the emergency measures related to the third red alert. The results show that the average daily emission reduction of pollutants was 678.4 t, the average concentration of PM_2.5 decreased by 79.1 μg·m^-3, and the average reduction ratio was 26.9% after the emergency measures were implemented. The increase of coal-fires, traffic, and other sources control the emergency measures, early alert start-up time, and inter-region joint prevention and effectively mitigate the increasing PM_2.5 concentration.

[Precipitation and Its Effects on Atmospheric Pollutants in a Representative Region of Beijing in Summer]

Atmospheric precipitation samples were collected in a representative region of Beijing in summer of 2015 to investigate the physical and chemical characteristics of atmospheric precipitation, the changes and causes of major chemical components in rainwater during the course of typical precipitation, and the impacts of typical precipitation processes on atmospheric pollutants. The volume-weighted mean pH value of rainwater in the representative region of Beijing in summer was 6.21 with the range of 5.15-7.34,and acid rain seldom occurred. The pollution elements Cd, Ca and Mn were moderately enriched, and Cu, Zn, Pb and S were seriously enriched in rainwater, of which Ca and S were main pollution elements, which accounted for 45.43% and 43.93% of the total pollution elements respectively, and Zn, Mn, Cu, Pb and Cd were main heavy metal pollution elements, which accounted for 1.32% of the total pollution elements. Different rates of precipitations could have different impacts on atmospheric pollutants. PM_2.5 could be scavenged by raindrop, and SO₂, NO₂ and O₃ could be scavenged greatly by raindrop during the precipitation episode at a relatively high rainfall rate, containing four significant stages, such as clear-out of atmospheric pollutants, accumulation, both accumulation and clear-out, and another clear-out of airborne pollutants. Atmospheric pollutants such as PM_2.5, SO₂, NO₂ and O₃ could mainly be scavenged by in-cloud scavenging processes during the precipitation episode at a relatively low rainfall rate, including four important stages, such as clear-out, both clear-out and accumulation, accumulation, and another clear-out of atmospheric pollutants. The effect of rainfall at a relatively high rate on atmospheric pollutants was bigger than that of rainfall at a relatively low rate.

[Seasonal Variation and Source Analysis for PM2.5, PM1 and Their Carbonaceous Components in Beijing]

Atmospheric particulate matter is the primary pollutant affecting the ambient air quality in most Chinese cities. In recent years, with the progress of monitoring technology and improvement in sampling equipment, the relevant research objects gradually shift from larger particle sizes (PM₁₀ and PM_2.5) to smaller particle size (PM₁). The carbonaceous component is an important part of atmospheric particulate matter. Taking Beijing as the research area, sampling for PM_2.5 and PM₁ was conducted in July and October of 2016, and January and April of 2017 as representative months of four seasons. Mass concentrations and seasonal variation characteristics for PM_2.5 and PM₁ were analyzed. The two-layer, nested, meteorology-air quality coupling model system (WRF-CMAQ) was used to model air circulation during the sampling period and thus analyze the source contributions for PM_2.5 and PM₁. The factor analysis method was also used to analyze the source apportionment of carbonaceous components. The results are as followed:the mass concentrations of PM_2.5 and PM₁ showed an increasing trend by spring, summer, autumn and winter. PM₁ was the main part of PM_2.5, and with the increasing frequency of haze in autumn and winter, the mass concentration ratio of PM₁/PM_2.5 became significantly higher. The authors contend that secondary pollution exists in Beijing's atmosphere, and SOC is more likely to accumulate in smaller particle size. Widespread coal combustion, vehicle emission, residential emission source and biomass combustion emissions are the major contributors to atmospheric particulates, while gasoline engine exhaust, diesel vehicle exhaust, biomass combustion and coal combustion emission are the main source of carbonaceous components in PM_2.5 and PM₁ in Beijing.

Effects of an Oral-Pharyngeal Motor Training Programme on Children with Obstructive Sleep Apnea Syndrome in Hong Kong: A Retrospective Pilot Study

Background

This study aimed to investigate the effects of an oropharyngeal motor training programme on children with Obstructive Sleep Apnea Syndrome (OSAS) in Hong Kong.

Methods

In this retrospective study, we reviewed the outcomes of 10 children with OSAS who had received an oropharyngeal motor training programme in Occupational Therapy Department of an acute hospital in Hong Kong over a 1-year programme. Each participant attended an individual oropharyngeal motor training programme plus a follow-up session after 2 months. The training programme consisted of 10 individual mobilization exercises involving the orofacial and pharyngeal area for 45 minutes. Each exercise had to be repeated for 10 times. Three outcome measures were chosen to study the effectiveness of the training programme including tongue strength, tongue endurance level and orofacial function. Tongue strength and tongue endurance level were assessed using the Iowa Oral Pressure Instrument (IOPI). The Nordic Orofacial Test-Screening (NOT-S) Assessment was used to assess the orofacial function. Seven out of 10 participants completed the training programme and attended the follow-up session after two months.

Results

The tongue strength and the scores of NOT-S of the 7 participants were found to have significant improvement after training. However, there was no significant difference in tongue endurance level.

Conclusion

The findings of this study support the role of occupational therapist in oromotor training modalities to improve the respiratory function for children with OSAS in Hong Kong. Copyright © 2017, Hong Kong Occupational Therapy Association. Published by Elsevier (Singapore) Pte Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

[Impact of the Electric Power Industry on Air Quality in Winter of Urban Agglomerations Along the Middle Reaches of the Yangtze River]

A WRF-CAMx-PSAT model was applied to analyze the impact of the electric power industry on urban agglomerations along the middle reaches of the Yangtze River. A high-resolution emission inventory based on a bottom-up approach was developed for air quality simulation. A typical month with heavy air pollution in this region (i.e., January) was chosen for simulation, and two mitigation scenarios were set for assessing lower capacity power units' impact on regional air quality. One scenario was for shutting down the lower capacity power units, and the other was for replacing lower capacity power units with higher capacity power units. Results showed that lower capacity power units contributed bigger pollutant concentrations to the regional contribution of the electric power industry. The concentration contributions of SO₂, NO_x, and PM_2.5 in the two mitigation scenarios were reduced by 36.2%-39.8%、30.5%-33.5%, and 25.9%-30.7%, respectively, than those under the current situation. Meanwhile, the decreases in pollutant concentration contribution for different regions were very similar for the two mitigation scenarios. In addition, lower capacity power units in four regions (i.e., northwest of Hubei province, west of Hunan province, Xiang-Jing-Yi economic belt region, and Hefei-centered urban agglomerations) contributed obviously to the regional pollutant concentration contributions of the electric power industry. Regional pollutant concentration contributions in the two mitigation scenarios were reduced by 40%-70%. Therefore, lower capacity power units make a bigger impact on the air quality of urban agglomerations along the middle reaches of the Yangtze River and should be paid special attention to achieve better regional air quality.

[Air Pollutant Emission Inventory from Iron and Steel Industry in the Beijing-Tianjin-Hebei Region and Its Impact on PM2.5]

The iron and steel industry, which discharges a large amount of pollutants including SO₂, NO_x, and PM_2.5, is the main source of atmospheric pollution in the Beijing-Tianjin-Hebei region. Based on the bottom-up method, a high temporal and spatial resolution emission inventory of the iron and steel industry in the Beijing-Tianjin-Hebei region was developed, which took into account the multiple air pollutants released during coking, sintering, pelletizing, ironmaking, steelmaking, and the steel rolling process. As the emission inventory showed, the total emissions of SO₂, NO_x, TSP, PM₁₀, PM_2.5, CO, and VOC from the iron and steel industry in the Beijing-Tianjin-Hebei region in 2015 were 388.2, 272.3, 791.9, 531.5, 386.8, 8233.8, and 265.3 kilotons, respectively, among which, sintering and pelletizing were the two processes discharging the most pollutants (17.0%-72.0%), followed by the ironmaking process (4.6%-42.4%) and the steel rolling process (3.5%-35.7%); the iron and steel industry in Tangshan discharged the most pollutants (39.1%-63.5%) among those in all the 13 cities. The impact of the iron and steel industry on the regional PM_2.5 concentration was simulated by a two-layer nested meteorology-air quality coupling model system (WRF-CMAx) with Particulate Source Apportionment Technology (PSAT). The simulation results showed that the iron and steel industry contributed 14.0%, 15.9%, 12.3%, and 8.7% of the PM_2.5 concentrations of the Beijing-Tianjin-Hebei region in spring, summer, autumn, and winter, respectively, and that the iron and steel industry had the most significant impact on the PM_2.5 concentrations in Tangshan among all the 13 cities, with a contribution rate up to 41.2%, followed by those in Qinhuangdao, Shijiazhuang, and Handan, with contributions of 19.3%, 15.3%, and 15.1%, respectively. The iron and steel industry has an important impact on the PM_2.5 concentration of the Beijing-Tianjin-Hebei region to which the government should pay more attention, and take more effective control measures to address this problem.

Magnetic surface molecularly imprinted poly(3-aminophenylboronic acid) for selective capture and determination of diethylstilbestrol

Imprinted poly(APBA) nanoshell on Fe₃O₄@SiO₂ surface was first synthesized and used for MSPE of diethylstilbestrol followed by HPLC determination.

[Characteristics of C2-C6 Hydrocarbons During the Winter Air Pollution Period in Beijing Urban Area]

A C2-C6 hydrocarbons monitoring campaign was carried out in the Beijing Southeastern Urban Area during December 2015. Twenty-five compounds excluding benzene were detected by an on-line VOCs analyzer; the sum of their concentrations is referred to as C2-C6 HCs in this study. During the monitoring period, C2-C6 HCs ranged from 12.4×10^-9 to 297.5×10^-9. The mean value of C2-C6 HCs reached 29.4×10^-9, 63.2×10^-9, 85.5×10^-9, 94.9×10^-9, and 131.8×10^-9, respectively, in AQ Ⅰ (air quality) (hourly PM_2.5<35 μg·m^-3), AQ Ⅱ (hourly PM_2.5:35-75 μg·m^-3), AQ Ⅲ (hourly PM_2.5:75-150 μg·m^-3), AQ Ⅳ (hourly PM_2.5:150-250 μg·m^-3), and AQ Ⅴ (hourly PM_2.5:>250 μg·m^-3). Moreover, the mole percentage of alkanes, alkenes, and ethyne significantly varied, 47% vs. 59%, 45% vs. 30%, and 7% vs. 12% (AQ I vs. AQ V). The diurnal variation of C2-C6 HCs presented two peaks at 08:00-09:00 and 17:00-18:00 not only in clean days (when 24-h PM_2.5<75 μg·m^-3) but also in polluted days (when 24-h PM_2.5>75 μg·m^-3). This result is consistent with the normal traffic pattern and indicates the significant impact of vehicle emissions on atmospheric hydrocarbon concentrations. Furthermore, we calculated the HCs/CO (×10^-9/×10^-6) ratio to prevent the impact of meteorological diffusion on C2-C6 HCs and to trace the physical transport process and the chemical degradation process of hydrocarbons. The C2-C6 HCs/CO ratio and the individual hydrocarbon to CO ratio presented a notable decreasing trend with worsening air quality, 90.6 (AQ Ⅰ), 63.8 (AQ Ⅱ), 56.9 (AQ Ⅲ), 37.4 (AQ Ⅳ), and 36.4 (AQ Ⅴ). However, the rate of decrease in the ratio of individual hydrocarbons to CO in the polluted period (AQ Ⅲ-Ⅴ) relative to the clean period (AQ I-Ⅱ) was never effectively related to the kinetic parameters of the reactions with the OH radical. Therefore, the strong chemical degradation of C2-C6 hydrocarbons in the polluted air was denied as the main reason. The HYSPLIT trajectory model showed that the transported air mass from the north and northwest and from the south and southwest prevail in the clean period and in the polluted period, respectively. Compared to the northern region, there were more sources of fossil fuel combustion in the southern region, which led to a lower HCs/CO ratio for the air mass in the southern region. Therefore, the increase in C2-C6 hydrocarbons during the polluted period was not only caused by the accumulation of local emissions but also by the air mass transport from the south.

[Clinical value of T-cell interferon releases detection of tuberculosis infection assay in quick diagnosis of spinal tuberculosis]

OBJECTIVE

To evaluate the value of T-cell interferon releases detection of tuberculosis infection(T-SPOT.TB)assay in quick diagnosis of spinal tuberculosis.

METHODS

From January 2012 to June 2015, a group of 122 diagnosed patients with spinal tuberculosis in the Qingdao Municipal Chest Hospital and a group of 86 patients suspected with spinal tuberculosis in Department of Orthopaedic, the Qingdao Third People's Hospital were accepted to undergone TB-DOT, T-SPOT.TB and TB-DNA PCR tests Department of Clinical Laboratory.

RESULTS

The sensitivity of TB-DOT, T-SPOT.TB and TB-DNA PCR tests were 69.7%, 86.1% and 56.6%, respectively.The sensitivity of T-SPOT.TB was significantly higher than TB-DOT and TB-DNA PCR tests (χ(2)=9.51, P<0.05; χ(2)=25.96, P<0.05). The specificity of TB-DOT, T-SPOT.TB and TB-DNA PCR tests were 62.8%, 88.3% and 91.9%, respectively.The specificity of T-SPOT.TB was significantly higher than TB-DOT test (χ(2)=15.25, P<0.05).

CONCLUSIONS

T-SPOT.TB assay possesses high sensitivity and specificity in quick diagnosis of patients with spinal tuberculosis, which is valuable in diagnosis of spinal tuberculosis.

[Air Pollutant Emission Inventory and Impact of Typical Industries on PM2.5 in Chengde]

In this study, detailed activity level of typical sector in Chengde in 2013 was obtained through a full-coverage investigation. A comprehensive emission inventory with country-level resolution in 2013 was developed based on guide of atmospheric pollutant emission inventory and updated emission factors. Then, the emission inventory within 1 km×1 km grid was generated using source-based spastial surrogates including population, road network and landuse date. Furthemore, meteorology-air quality modeling system (WRF-CMAx) including Particulate Source Apportionment Technology (PSAT) module was established in order to evaluate the impact of topical sector (e. g., electric power, the production of construction materials, the metallurgical industry, etc.) on PM_2.5 concentration in January, April, July and October which were considered as the representative months of winter, spring, summer and autumn. The results showed the total emission of SO₂, NO_x, TSP, PM₁₀, PM_2.5, CO, VOCs and NH₃ in Chengde in 2013 was respectively 81134 t, 72556 t, 368750 t, 119974 t, 51152 t, 1281371 t, 170642 t and 81742 t. Industrial source was the main emission contributor of SO₂, NO_x, CO, VOCs, accounting for 89.5%, 51.9%, 82.5% and 45.6% of total emissions, respectively. The major emission source of NO_x also included on-road and non-road mobile source, respectively accounting for 26.7% and 10.8%. The major emission source of TSP, PM₁₀ and PM_2.5 was fugitive dust, accounting for 76.7%, 65.6% and 46.54%, respectively. Ammonia emissions from animals and farm accounted for 67.1% and 15.8% of total emissions, respectively. The numerical simulation result showed that the fugitive dust, the others, the metallurgical industry and boilers industry had relatively higher contributions to PM_2.5 concentration, accounting for 23.1%, 20.6%, 13.3% and 11.2%, respectively. These emission sources should be paid more attention during the decision-making with respect to control strategies.

Highly sensitive aptasensor based on synergetic catalysis activity of MoS2-Au-HE composite using cDNA-Au-GOD for signal amplification

Single or few-layer nanosheets of MoS₂ (MoS₂ nanosheets) and a composite composed of MoS₂ nanosheets, Au nanoparticles (AuNPs) and hemin (HE) (denoted as MoS₂-Au-HE) were prepared. The composites possessed high synergetic catalysis activity towards the electroreduction of hydrogen peroxide. Furthermore, glucose oxidase (GOD) and AuNPs were used as marker of the complementary DNA (cDNA) strand of kanamycin aptamer to prepare a conjugate (reffered as cDNA-Au-GOD) that was designed as the signal probe. Both cDNA-Au-GOD and MoS₂-Au-HE were applied to fabricate aptasensor for kanamycin. MoS₂-Au-HE acted as solid platform for kanamycin aptamer and signal transmitters. AuNPs were employed as the supporter of cDNA and GOD which catalyze dissolved oxygen to produce hydrogen peroxide in the presence of glucose. Then cathodic peak current of H₂O₂ was recorded by differential pulse voltammetry (DPV). The electrochemical reduction of H₂O₂ was catalyzed by MoS₂-Au-HE that was modified onto the surface of a glassy carbon electrode (GCE). The cathodic peak current of H₂O₂ was highly linearly decreased with an increase of kanamycin concentrations from 1.0ng/L to 1.0×10⁵ng/L, with a detection limit of 0.8ng/L. This aptasensor can be used to detect kanamycin in milk with high specificity, sensitivity and selectivity.

[Second-line treatment for metastatic or locally advanced gastric cancer]

Gastric cancer is one of the major causes of cancer-related deaths. Many patients with metastatic gastric cancer after first-line chemotherapy received salvage chemotherapy in routine clinical practice. Recent phase Ⅲ trials demonstrated substantial prolongation of overall survival to support this chemotherapy or targeted therapy as a second-line treatment. Both ramucirumab monotherapy and ramucirumab plus paclitaxel were approved by FDA in patients with previously treated advanced gastric or gastroesophageal junction adenocarcinoma. In addition, paclitaxel, irinotecan, or docetaxel monotherapy is also recommended for preferred regimens. This review will summarize chemotherapy or targeted therapy as a second-line treatment in advanced gastric cancer.

Radiation costing methods: a systematic review

OBJECTIVE

Costs for radiation therapy (rt) and the methods used to cost rt are highly diverse across the literature. To date, no study has compared various costing methods in detail. Our objective was to perform a thorough review of the radiation costing literature to identify sources of costs and methods used.

METHODS

A systematic review of Ovid medline, Ovid oldmedline, embase, Ovid HealthStar, and EconLit from 2005 to 23 March 2015 used search terms such as "radiation," "radiotherapy," "neoplasm," "cost," " cost analysis," and "cost benefit analysis" to locate relevant articles. Original papers were reviewed for detailed costing methods. Cost sources and methods were extracted for papers investigating rt modalities, including three-dimensional conformal rt (3D-crt), intensity-modulated rt (imrt), stereotactic body rt (sbrt), and brachytherapy (bt). All costs were translated into 2014 U.S. dollars.

RESULTS

Most of the studies (91%) reported in the 33 articles retrieved provided rt costs from the health system perspective. The cost of rt ranged from US$2,687.87 to US$111,900.60 per treatment for imrt, followed by US$5,583.28 to US$90,055 for 3D-crt, US$10,544.22 to US$78,667.40 for bt, and US$6,520.58 to US$19,602.68 for sbrt. Cost drivers were professional or personnel costs and the cost of rt treatment. Most studies did not address the cost of rt equipment (85%) and institutional or facility costs (66%).

CONCLUSIONS

Costing methods and sources were widely variable across studies, highlighting the need for consistency in the reporting of rt costs. More work to promote comparability and consistency across studies is needed.

Expression Patterns of Three Genes Under Short and Long Term Cold Exposure in Thitarodes pui (Lepidoptera: Hepialidae), A Host of Ophiocordyceps sinensis

　　BACKGROUND: Thitarodes larvae are the host of the caterpillar fungus Ophiocordyceps sinensis. Low temperature is the main environmental limitation for larvae growth.

OBJECTIVE

To better understand the cold adaption process in T. pui larvae, the expression patterns of trehalose-6-phosphate synthase (TpTPS), heat shock protein 70 (TpHSP70), and heat shock protein 90 (TpHSP90) were investigated upon short and long-term exposure to 0°C.

MATERIALS AND METHODS

The 6th instar T. pui larvae were collected in July 2013. TpTPS was firstly sequenced and expression patterns of TpTPS, TpHSP70 and TpHSP90 were investigated using quantitative PCR.

RESULTS

Full-length cDNA of TpTPS was 3,012 bp, with an open reading frame of 2,472 bp and an encoding protein of 823 amino acids. TpTPS up-regulation was induced by cold exposure. TpHSP70 expression is altered by cold exposure, but remained low. TpHSP90 expression was obviously up regulated in long-term cold stimulation.

CONCLUSION

All three genes (TpTPS, TpHSP70 and TpHSP90) have likely contributed to cold tolerance in T. pui larvae, TpTPS and TpHSP90 potentially being more important.

Molecular cloning and characterization of GbMECT and GbMECP gene promoters from Ginkgo biloba

Ginkgolides are key pharmaceutical components in Ginkgo biloba. Using the cDNA sequence of the MECP and MECT genes to design primers, we obtained the promoters of these genes from Ginkgo genomic DNA using the genome walking method. The two promoters were 744 and 982 bp in length, respectively. The cis-elements of the GbMECPs and GbMECT promoters were predicted and analyzed using the plant cis-acting regulatory element database. We found major cis-elements in the sequence of the GbMECT and GbMECPs promoters. The GbMECP promoter contains six TATA boxes and eight CAAT boxes. The GbMECT contains five TATA boxes and seven CAAT boxes. Furthermore, some cis-elements in the promoters of GbMECPs and GbMECT included hormone and light-regulated elements, UB-B-induced elements, and stress-related dehydration-responsive elements. Expression analysis results showed that the MECP gene is mainly involved in responses to CCC (cycocel) and UV-B, and that MECT is mainly involved in responses to wounding treatment. These results also showed that the expression model was consistent with the cis-elements present. During the annual growth cycle, the level of GbMECPs was significantly correlated with terpene lactones accumulation in leaves. A fitted quadratic curve showed the best model for correlating GbMECPs with terpene lactones in leaves. These results will help us to understand the transcriptional regulatory mechanisms involved in key gene expression and ginkgolide accumulation in G. biloba.

Dietary Supplementation of Magnesium Sulfate during Late Gestation and Lactation Affects the Milk Composition and Immunoglobulin Levels in Sows

This experiment was conducted to investigate the effects of dietary supplementation of magnesium sulfate (MgSO₄) during late gestation and lactation on sow and litter performance, fecal moisture, blood biochemistry parameters, immunoglobulin levels and milk composition in sows. Forty-eight sows (Yorkshire×Landrace, 4th to 5th parity) were randomly allocated to 1 of 4 dietary treatments supplemented with 0, 200, 400, or 600 mg/kg MgSO₄ (n = 12). The experiment started on day 90 of gestation and continued through day 21 of lactation. Blood samples were collected on day 107 of gestation, day 0 (farrowing) and 21 (weaning) of lactation for the analyses of the blood biochemistry parameters and immunoglobulin levels. The colostrum and milk samples were obtained on day 0 and 14 of lactation, respectively. Fecal samples were collected from the sows on day 107 of gestation as well as day 7 and 20 of lactation to determine fecal moisture content. The results showed that the survival percentage of piglets and the litter weight at weaning were decreased linearly (p<0.05) and other parameters of the sow or litter performance were not influenced (p>0.05) by MgSO₄ supplementation. The fecal moisture content of the sows were increased (p<0.05) linearly as dietary MgSO₄ increased on day 7 and 20 of lactation. Supplementation with MgSO₄ increased the plasma magnesium (Mg) level linearly (p<0.05) and had a trend to increase total protein level (p>0.05 and p<0.10). However, an increase in the dietary MgSO₄ level resulted in a linear decrease in the colostrum fat content (p<0.05). Dietary MgSO₄ supplementation enhanced the immunoglobulin G (IgG) level (linear, p<0.05) in plasma on day of farrowing and immunoglobulin A (IgA) level in colostrum (quadratic, p<0.05) and milk (linear, p<0.05) of the sows. These results indicated that supplementation with MgSO₄ during late gestation and lactation may have the potential to prevent sow constipation, but may also result in some negative effects.

Functional characterization of the Ginkgo biloba chalcone synthase gene promoter in transgenic tobacco

The regulative sequence (2273 bp) of the chalcone synthase gene promoter of biloba was cloned by genomic walking. A 2273-bp promoter 5' upstream translation start site of GbCHS was cloned and designated as GbCHSP. pBI121+CHSP:GUS and pBI121-35S:GUS were constructed and transformed into tobacco by LBA4404. We found that GbCHSP could drive transient expression of GUS in tobacco and differentially expressed in root, stem and leaf tissues of this plant. GUS activity regulated by the CHSP promoter were located in tissues (apical meristems) at the growing points of roots and stems. pBI121+CHSP:GUS could be induced by wounding, copper, UV-B, abscisic acid, and ethephon treatments of transgenic seedlings. This activity was weakly inhibited by gibberellin. Deletion analysis of the CHSP promoter in transgenic tobacco showed that CHSP1 complete promoter conferred a GUS expression and activity similar to that of 35 S(CaMV). GUS activity dropped dramatically when there were CHSP4, CHSP5 constructs and was almost totally absent when the CHSP6 construct was present. We conclude that the upstream sequence -1548 to -306 of GbCHSP is the main region for transcriptional regulation of the CHS gene and that it is activated by hormone and stress factors in G. biloba. These results will help us to understand the transcriptional regulatory mechanisms involved in GbCHS expression and flavonoid accumulation in G. biloba.

Effectiveness of maifanite in reducing the detrimental effects of cadmium on growth performance, cadmium residue, hematological parameters, serum biochemistry, and the activities of antioxidant enzymes in pigs

This study was conducted to investigate the toxicity of cadmium and to evaluate the effectiveness of maifanite in preventing cadmium-induced adverse effects. Thirty-two crossbred pigs (Duroc × Landrace × Large white, sex balanced, 17.25 ± 0.07 kg average body weight) were randomly allotted to one of four dietary treatments in a 2 × 2 factorial arrangement, with eight replicates per treatment and one pig per replicate. The dietary treatments included two cadmium (as CdCl2) doses (0.32 and 30.49 mg/kg) and two maifanite doses (0 and 1%). The results showed that pigs treated with cadmium decreased their average daily feed intake (P < 0.05) and increased (P < 0.05) the feed/gain ratio. Cadmium was found in the tissues of pigs that were fed with cadmium-contaminated diets, but the level of cadmium was much lower when maifanite was added to the cadmium-contaminated diets. Ingestion of diets that were artificially contaminated with cadmium (30.49 mg/kg of cadmium) reduced (P < 0.05) the number of lymphocytes, the total erythrocyte count, the hemoglobin level, and the hematocrit. However, the activities of serum aspartate aminotransferase and gamma glutamyltransferase were increased (P < 0.05). The total protein level was lower (P < 0.05) in pigs fed with cadmium-contaminated diets. The contents of malondialdehyde increased (P < 0.05), while the total antioxidant capacity and the activities of total superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and catalase decreased (P < 0.05) in pigs fed with cadmium-contaminated diets. Dietary addition of maifanite can, to some extent, prevent the negative effects associated with feeding cadmium diets (30.49 mg/kg of cadmium) to pigs.

Molecular cloning and characterization of GbDXS and GbGGPPS gene promoters from Ginkgo biloba

Ginkgolides are key pharmaceutical components in Ginkgo biloba leaves. 1-Deoxy-D-xylulose-5-phosphate synthase (GbDXS) and geranylgeranyl pyrophosphate (GbGGPPS) genes are critical genes involved in ginkgolide biosynthesis. In this study, the promoters of GbDXS and GGPPS, with 676 and 570 bp in length, respectively, were cloned by chromosome walking. The cis-elements of GbDXS and GbGGPPS promoters were predicted and analyzed by the plant cis-acting regulatory element (CARE) database. We found some major cis-elements in the sequence of GbDXS and GbGGPPS promoters. The GbDXS promoter has 3 TATA boxes, 10 CAAT boxes, 6 GATA boxes, and 1 I box. The GbGGPPS promoter has 1 TATA box, 6 CAAT boxes, 6 GATA boxes, and 4 I boxes. Furthermore, some stress-related cis-elements in the promoters of GbDXS and GbGGPPS were found to be light-regulated elements, including sequences over-represented in light-induced promoters (SORLIP1- AT), GATA box, and I box, a gibberellin-responsive element (WRKY), salicylic acid-induced (GT-1), cold- and dehydration-responsive (MYC-Core), and copper-inducible (CURE-Core). Further analyses of these cis-elements will aid in elucidating the molecular mechanisms regulating the expression of the GbDXS and GbGGPPS genes during ginkgolide accumulation in G. biloba.

Changes in first hip fracture rates in British Columbia Canada, 1990-2004

We determined age-standardized first hip fracture rates in British Columbia between 1990 and 2004. We found sex and fracture type rates in keeping with previous reports and that fracture rates have decreased approximately 18% overall in both men and women.

INTRODUCTION

To determine whether there have been changes in the age-, sex-, and subtype-specific first hip fracture rates in Canadian province of British Columbia (BC) between 1990 and 2004.

METHODS

Records of all persons aged 60 years and older hospitalized with hip fractures in BC between 1985 and 2004 were obtained from the Canadian Institute for Health Information Discharge Abstract Database. Only the first hip fracture records were included, and fractures likely due to causes other than trauma were excluded. Age- and sex-specific rates were calculated using population denominators from Statistics Canada and direct standardization was used. Age-standardized rates allowed for comparison across years with adjustment for age distribution.

RESULTS

There were 41,990 records of first hip fracture included, and 73% were in women. Trends in age-specific rates by fracture type were similar to previous reports. Between 1990 and 2004, there has been an age-adjusted 18% decrease in first hip fracture rates in women, and 19% decrease in first hip fracture rates in men. The decrease was statistically significant in femoral neck fractures in women, but not in men.

CONCLUSIONS

There has been a decrease in age-adjusted hip fracture rates in BC between 1990 and 2004, which is in contrast to previous projections for hip fracture rates in Canada.

Geographic trends in incidence of hip fractures: a comprehensive literature review

A comprehensive review of literature was conducted to investigate variation in hip fracture incident rates around the world. The original crude incidence rates were standardized for age and sex for comparability. After standardization, the highest rates of hip fracture were found in Scandinavia and the lowest rates in Africa.

INTRODUCTION

This study was conducted to investigate the geographic trends of the incidence of osteoporotic hip fractures through a comprehensive review of literature.

METHODS

Studies were identified for inclusion in the review by searching the MEDLINE database via PubMed and applying strict inclusion and exclusion criteria. Age-specific incidence rates were extracted from the articles, and in order to provide a common platform for analysis, we used directly age-standardized and age-sex-standardized rates (using the 2005 United Nations estimates of the world population as standard) to complete the analysis.

RESULTS

Forty-six full text articles spanning 33 countries/regions were included in the review. For ease of comparison, the results were analyzed by geographic regions: North America, Latin America, Scandinavia, Europe (excluding Scandinavia), Africa, Asia, and Australia. The highest hip fracture rates were found in Scandinavia and the lowest in Africa. We found comparable rates from countries in North America, Australia, and Europe outside of Scandinavia. The diverse makeup of the Asian continent also resulted in quite variable hip fracture rates: ranging from relatively high rates in Iran to low rates, comparable to those from Africa, in mainland China.

CONCLUSIONS

Given the aging of populations globally, and in the industrialized countries specifically, hip fractures will become a progressively larger public health burden. The geographic trends observed in hip fracture incidence rates can provide important clues to etiology and prevention.

[Self-assembled gold nanoparticles modified electrode for electrochemical detection nitrite]

A modified sensor was fabricated by N-[3-(trimethoxysilyl) propyl]-ethylene diamine (TSPED) and colloidal gold particles (AuNPs) on glass carbon electrode (GCE). Atomic force microscopy (AFM) demonstrated that the colloidal gold particles were self-assembled onto the amine groups of the sol-gel. Due to the excellent electrocatalytic activity of gold nanoparticles toward the oxidation of nitrite and the interaction between the protonated TSPED film and the negatively-charged nitrite, the operating potential for nitrite oxidation was shifted about 140 mV to negative side, compared to bare GCE. The differential pulse voltammetry and the differential pulse amperometry were employed in the process of electrochemical measurements. Under the optimal conditions, a highly linear response to nitrite in the concentration range of 5.0 x 10(-7)-1.0 x 10(-3) mol x L- was observed, with a detection limit of 2.0 x 10(-7) mol x L(-1) (S/N = 3). The real water samples were investigated and the results were in good agreement with those obtained by standard spectrophotometric method. This method proposed by this paper possesses high sensitivity and good reproducibility.

Play fighting and corticotropin-releasing hormone in the lateral septum of golden hamsters

This study was focused on determining the possible role of corticotropin-releasing hormone (CRH) on play fighting in juvenile golden hamsters. As no specific neural sites have been proposed, we looked for changes in CRH innervations at the peak of play-fighting activity on postnatal day 35 (P-35) from a week before on P-28. We noted that the increase in play-fighting activity between these two dates was associated with a 100% increase of the density of CRH fibers within the lateral septum. We, then, tested the possible role of CRH receptors on play fighting within the lateral septum through microinjections of alpha-helical CRH, a CRH receptor antagonist (either 0, 30, or 300 ng), directly into the area. The treatments inhibited play-fighting attacks and pins as well as reduced the duration of time that the resident hamsters spent in contact with the intruders, though locomotor activity remained unaffected. The possible source of CRH release in the lateral septum was addressed by quantification of CRH neurons also labeled with a marker of cellular activity, c-Fos, after consummation of play fighting. CRH neurons in the horizontal part of the diagonal band, an area reciprocally connected with the lateral septum, showed a 75% increase in double labeling with c-Fos as compared to controls. Together, these data show that CRH receptors in the lateral septum have a general role on play fighting, not just facilitating its consummation, but also likely enhancing appetitive aspects as well. In addition, this effect is associated with enhanced CRH availability in the area and enhanced neuronal activity within interconnected areas.

CALHM1 variant is not associated with Alzheimer's disease among Asians

In a case control study involving 484 study subjects, we showed that the CALHM1 allele (13.5% vs 16.7%) and genotype frequency was not significantly different between Alzheimer's disease (AD) and controls. Logistic regression analysis did not reveal any interaction between ApoE4 allele and CALHM1 allele.