Research on PM2.5 estimation and prediction method and changing characteristics analysis under long temporal and large spatial scale - A case study in China typical regions.

High concentration of fine particulate matter (PM2.5) has been shown to be a major contributor to haze weather, which has been associated with an increased prevalence in lung cancer. An accurate estimation and predication of PM2.5 historical levels, and its spatial-temporal variability can assist in strategically improving regional air quality and reducing its harmful effects on population health. This paper targets Beijing, Tianjin, and Hebei province (BTH), three northeast province of china (TNPC), Yangtze river delta (YRD) and pearl river delta (PRD) as the study areas. Data used in this study include PM2.5 measurements from April 2013 to December 2016, MODIS AOD raster imageries and five meteorological factors from 2000 to 2016. By combining back propagation artificial neural network (BPANN) and ε-support vector regression (ε-SVR), a novel hybrid model was constructed to impute the historical PM2.5 missing values in the long time series from 2000 to 2012, and to predict the concentration of PM2.5 from April 2014 to December 2017. The hybrid model produced results superior to BPANN and ε-SVR with a higher accuracy, lower error rate, and a stable performance. This model can be applied to the other four regions with consistent results. Results of spatial-temporal analysis indicated that the PM2.5 concentration has increased along with a pollution range expansion in BTH from 2000 to 2010. In addition, the PM2.5 concentration decreased slowly in PRD. The concentration and pollution range of PM2.5 in TNPC and YRD showed a stable trend. In 2012, the four research areas all showed decreased trend, and the pollution range narrowed. From 2013 to 2016, the PM2.5 concentration increased shortly then decreased; in particular, the high pollution areas saw a decrease in PM2.5 concentration, which correlated with control measures adopted by the state during the same time period. The hot spots of PM2.5 were mainly distributed in the inland cities.

Thermodynamic analysis of air-ground and water-ground energy exchange process in urban space at micro scale.

With an acceleration of urbanization in China, a large number of natural underlying surface have been replaced by impervious surface, which seriously affect the urban thermal and water environment. In this study, we focus on four typical urban underlying surfaces, asphalt, cement, pervious brick, and lawn. Based on the theory of heat transfer and fluid mechanics, we establish a solar radiation model and a rainfall convection model to analyze the heat transfer process of thermal radiation, thermal conduction, and thermal convection of urban underlying surface under different meteorological conditions. The fitting effects of both models are good: For solar radiation model, 0.89 ≤ R2 ≤ 0.99, 1.93 °C ≤ RMSE≤2.45 °C, 1.87 °C ≤ MAE ≤ 2.17 °C. For rainfall convection model, 0.95 ≤ R2 ≤ 0.96, 0.17 °C ≤ RMSE≤0.21 °C, 0.15 °C ≤ MAE ≤ 0.2 °C. Results show that: 1) In the absence of rainfall, the land-surface temperature of asphalt, cement, and pervious brick underlying surface is higher than air temperature, which has a positive effect on urban near-surface air temperature. In addition, the lawn underlying surface with the lowest temperature and the lowest temperature difference has a negative impact on the urban surface temperature. 2) In the rainfall, the underlying surface transfers heat to the runoff in the form of convection, forcing the runoff temperature to rise. Asphalt has the most obvious heating effect on runoff and lawn has the least effect on runoff temperature. The study proposes that the land-surface temperature can be lowered by paving lawn in hot places, and the pervious underlying surface should be adopted in the areas adjacent to the water bodies to reduce the influence of the underlying surface on runoff temperature.

Expression and polyclonal antibody preparation of the tegument protein UL48 encoded by MDV / 中国兽医学报

UL48 plays essential role in replication of MDV genome and interacts with UL36 as well as other MDV tegument proteins.To investigate the interaction between UL48 and UL36 during MDV oncogenisis,antibody against UL48 was prepared and characterized in current study.UL48 gene was amplified from MDV-Ⅰ genome and then subcloned into pTYB1 and pGEX-4T3 vectors for UL48 expression with induction of IPTG in BL21(DE3) E..coli cells.Chitin-sepharose and Glutathion-sepharose were,respectively,used to purify fusion protein intein-UL48 and GST-UL48.Four subcutaneous injections of intein-UL48 fusion protein were done on the lower back and the thigh of rabbit and then other three injections with an interval 10 days.The titer of antibody was measured by the sandwich ELISA with UL48 protein isolated from GST-UL48 after cleavage of thrombin.Western blot was carried out for specificity analysis of antibody against UL48 protein.The results suggested that UL48 antibody was succesfully prepared,and its titer was 1 ∶ 512 000.

Dynamic change of cystathionine β-synthase during cerebral ischemia-reperfusion and its effect in rats / 中国免疫学杂志

Objective:To observe the dynamic change of cystathionine β-synthase during cerebral ischemia-reperfusion and its effect in rats.Methods:The ischemic model was established with line embolism to block the middle cerebral artery .The reverse tran-scription-polymerase chain reaction ( RT-PCR) and Western blot assay were used to assess the expression of cystathionine β-synthase (CBS) in SHAM group,I group,and IR group.ELISA assay was performed to detected the homocysteine (HCY) level in plasma.After treating with the inhibitor of cystathionine β-synthase called hydroxyla mine(HA),the expression of hemeoxygenase 1(HO-1) and the pathologic change of the brain was evaluated .Results:As compared to sham group ,the expression of CBS was significantly up-regulated in ischemia-reperfusion group at 12 h post-reperfusion.Meanwhile,it existed the lowest level of HCY at 12 h post-reperfusion,comparing to sham grouzp ( 5.73 ±1.17 vs 2.88 ±0.93 , F=25.56 , P=0.001 ) .When inhibited the activity of CBS via using HA , the down-regulation of HO-1 protein and further damage in neuron were observed .Conclusion:Cystathionine β-synthase serves as an protective factor during cerebral ischemia-reperfusion.

Investigation and analysis of hand hygiene facilities at all levels of TCM hospitals in Guangxi / 中华医院管理杂志

Objective Survey of Guangxi Traditional Chinese Medicine hospital hand hygiene facilities at all levels was made with improvement measures proposed.Methods Hand Hygiene Norms for Medical Workers questionnaires designed by the Ministry of Health was used in a field survey on hand hygiene facilities of 89 TCM hospitals in Guangxi.Results Facilities of the non-hand-touch taps,hand sanitizer and hand disinfectants were found satisfactory at key departments at all TCM hospitals in the region,yet poor performance with the hand drying facilities.Hospitals with such departments with non-hand-touch taps,hand sanitizer and hand disinfectants accounted for 93.3％,100.0％ and 100.0％.Only 41.6％ of the hospitals were found to use dry hand towels as drying facilities.Significant difference was found at various levels of hospitals' hand hygiene facilities.Conclusion The hand hygiene facilities at such hospitals in Guangxi are receiving growing attention,yet further investment is still required for further improvement and compliance of the medical staff in hand hygiene.

MSCT measurement of anterior clinoid process and clinoid segment of internal carotid artery / 实用放射学杂志

Objective To observe the anatomy status of the anterior clinoid process (ACP)and the anterior clinoid segment of in-ternal carotid artery (ICA)respectively by multisliced computed tomography (MSCT),and to provide useful imaging information for ACP removal surgery.Methods A total of 100 patients (200 sides)had volume rendering reconstruction of skull.Cranium was removed along cranio-orbital bone in simulation.Then the anatomical structures of the ACP and its surrounding were observed in cephalad direction.The total length,medium length,basic width,medium width of the ACP and the sagittal view curve length of anterior clinoid segment of the ICA from both sides were measured.Results Total length of left ACP was (9.82±2.48)mm,basal width was (9.47±1.88)mm,medium length was (5.03±1.55)mm,medium width was (6.1 9 ±1.75)mm;for right side total length was (10.41±2.1 6)mm,basal width was (9.66 ±2.21)mm,medium length was (5.86 ±2.48)mm,medium width was (6.66±1.5 1)mm.Left anterior clinoid segment of ICA curve length was (6.74±2.25)mm;right was (8.54±3.00)mm.Paired sample t test showed no significant difference in total length,basal width and medium width of ACP in both sides (P >0.05);while the difference in medium length and curve length of the anterior clinoid segment of ICA were statistically significant respectively (P <0.05).Conclusion MSCT can clearly display the vivisection and variation status of the ACP and the anterior clinoid segment of the ICA and can provide useful imaging information for removal of ACP in operation.

Multislice Spiral CT-based Simulation in Enlarging Exposure Extent of Internal Carotid Artery Siphon Before and After Removing Anterior Clinoid / 中国医学影像学杂志

Purpose To study the exposure extent of internal carotid artery siphon (ICAS) before and after removing anterior clinoid process (ACP) using multislice spiral CT (MSCT) simulation, and to improve the tumor resection rate and ensure the operation effect. Materials and Methods MSCT three-dimensional images reconstruction simulating supraorbital keyhole approach of 100 patients (200 sides) were observed, the distance between the crotch of anterior cerebral artery and middle cerebral artery and ICAS before and after removing ACP (exposure extent) was measured. Results In 100 patients (200 sides ACP), the exposure extent before and after removing ACP were (14.3±3.9) mm and (30.5±4.2) mm, respectively on the left side with statistical difference (t=45.278, P0.05). Conclusion MSCT simulating supraorbital keyhole approach in removing ACP can effectively increase the exposure length of ICA, and enlarge the exposure extent of sella region, thus provide reliable imaging information for removing tumor and selecting surgical project in this region.

Spatially refined time-varying reproduction numbers of SARS-CoV-2 in Arkansas and Kentucky and their relationship to population size and public health policy, March - November, 2020

PurposeTo examine the time-varying reproduction number, Rt, for COVID-19 in Arkansas and Kentucky and investigate the impact of policies and preventative measures on the variability in Rt. MethodsArkansas and Kentucky county-level COVID-19 cumulative case count data (March 6-November 7, 2020) were obtained. Rt was estimated using the R package EpiEstim, by county, region (Delta, non-Delta, Appalachian, non-Appalachian), and policy measures. ResultsThe Rt was initially high, falling below 1 in May or June depending on the region, before stabilizing around 1 in the later months. The median Rt for Arkansas and Kentucky at the end of the study were 1.15 (95% credible interval [CrI], 1.13, 1.18) and 1.10 (95% CrI, 1.08, 1.12), respectively, and remained above 1 for the non-Appalachian region. Rt decreased when facial coverings were mandated, changing by -10.64% (95% CrI, -10.60%, -10.70%) in Arkansas and -5.93% (95% CrI, -4.31%, -7.65%) in Kentucky. The trends in Rt estimates were mostly associated with the implementation and relaxation of social distancing measures. ConclusionsArkansas and Kentucky maintained a median Rt above 1 during the entire study period. Changes in Rt estimates allows quantitative estimates of potential impact of policies such as facemask mandate.