Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
Abstract： Global warming intensifies regional water cycles and alters water vapor transport routes. Investigatingstable isotope traits in diverse precipitation grades and identifying water vapor origins can offer insights forefficient water resource utilization and drought- flood management. By analyzing precipitation samples fromYinchuan Plain in the May- October summer half- years of 2018- 2020, the hydrogen and oxygen isotopefluctuations across precipitation levels and their secondary evaporation effects were estimated in this study.Backward trajectory modeling and water vapor flux methods were applied to determine vapor sources andpotential evaporation areas. The findings revealed that the stable isotope signature in Yinchuan Plain during thesummer half-year decreased with increased rainfall levels; light rain exhibited negative d-excess values, whereasmoderate and heavy rains showed positive values. The slope and intercept of the regional atmosphericprecipitation line diminished as rainfall magnitude increased. Secondary evaporation intensified with higher airtemperature, but decreased with increased precipitation, air relative humidity, and raindrop diameter. Distinctwater vapor origins existed across precipitation levels: westerly vapor dominated light rain, whereas moderateand heavy rains originated not only from westerly vapor but also from high latitude land evaporation vapor andsoutheast ocean vapor, respectively. Potential evaporative vapor source areas predominantly influenced light andmoderate rainfall, encompassing the study area’s vicinity as well as northwest and southeast regions. Moderaterainfall events were largely observed in the study area’s vicinity, as well as northwest and southeast regions,whereas heavy rainfall clustered around the study area and the southeastern region.
Subjects: Medicine, Pharmacy >> Clinical Medicine Subjects: Management Science >> Science ology and Management submitted time 2023-12-09
Abstract： A comparison of pivotal studies for high-risk medical devices between China and the US including 40 approved products and some undergoing studies, covering coronary intervention, structural heart disease, left ventricular assistant device, neuromodulation, and electrophysiology, showed that pivotal studies in China were relatively simple-designed, with more quantitative endpoints, and relatively small sample size. Direct comparison of pivotal studies between different class medical devices is difficult, but achieving consensus between sponsors and regulation administration agency before conducting of the pivotal studies should be our future direction.
Peer Review Status:
Awaiting Review
Subjects: Medicine, Pharmacy >> Clinical Medicine Subjects: Management Science >> Other Disciplines of Management Science submitted time 2023-12-09
Abstract： We collected summaries/review reports of fractional flow reserve (FFR) and related products approved in the US and China, and together with relevant clinical literature and clinical guidelines, analyzed the registration administration strategy for such medical device software, especially clinical data requirement. In general, the US is more flexible regarding clinical data request, which was not even submitted for early FFR products when clinical benefits were not claimed. Clinical data was submitted for the following products during equivalence demonstration; however, mainly being diagnostic consistence comparison study with predicate device instead of strict prospective clinical trials. When the clinical benefits were confirmed in clinical trials with clinical outcome as the primary endpoint, this claim was added to product indications. Besides, the practice of efficiently leveraging social resources via data sharing in the US is worth learning.
Peer Review Status:Awaiting Review
Subjects: Medicine, Pharmacy >> Clinical Medicine Subjects: Statistics >> Biomedical Statistics submitted time 2022-11-21
Abstract： Sample size determination for clinical trials is one of the key components of study design. Based on medical device registration review recently published by National Medical Products Administration, Center for Medical Device Evaluation, and other public information, we conducted an analysis of the sample size for medical device registration clinical trials, including study design, part of which being compared with that in the US. Our results showed that the median sample size for Class III medical device registration trials is 120 (IQR 90~167.5). Sample size was influenced significantly by regulation policies, and some differed significantly from that in the US. Disclose of registration review is a giant leap for medical device regulation in China; however, the disclosed information needs to be further improved.
Peer Review Status:Awaiting Review
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2021-04-23 Cooperative journals: 《干旱区研究》
Abstract：饱和水汽压差是土壤-植被-大气连续体水分传输过程的关键影响因素，在全球气候变化背景下，预测西北地区饱和水汽压差，对于植被恢复和农林业气象灾害风险评估具有重要的现实意义。基于西北五省（区）1990—2019年月饱和水汽压差值，采用趋势分析和小波分析等方法研究了西北地区饱和水汽压差年际变化特征和周期性变化规律；采用指数模型和ARIMA模型，筛选最佳样本步长和预测步长，对西北地区饱和水汽压差进行模拟和预测。结果表明：（1）西北五省（区）中，新疆年均饱和水汽压差最高，其次为宁夏、陕西、甘肃和青海；近30 a整体上西北地区饱和水汽压差呈上升趋势，其中宁夏和新疆饱和水汽压差上升幅度最大，分别为0.036 kPa·(10a)-1和0.033kPa·(10a)-1，其次为甘肃［0.026 kPa·(10a)-1］、青海［0.021 kPa·(10a)-1］和陕西［0.012 kPa·(10a)-1］；（2）西北各省（区），16 a尺度周期对小波方差贡献最大，为饱和水汽压差变化的主周期。此外，陕西、甘肃和新疆还存在24~27 a的周期特征，方差贡献较小；（3）相对于指数模型，ARIMA模型均方根误差平均减少42.3%，决定系数R2平均提高11.1%，Nash-Sutclife效率系数平均提高17.7%，有效提高了饱和水汽压差预测精度；（4）未来一段时间内，西北各地区饱和水汽压差均存在不同程度的升高趋势，以宁夏和新疆地区的饱和水汽压差增幅最为明显，分别为9.5%和8.9%。
Subjects: Biology >> Bioengineering submitted time 2017-06-01 Cooperative journals: 《中国生物工程杂志》
Abstract： The relationship between Fas apoptosis inhibitory molecule FAIM 1 and simple obesity was studied by using the blood of obese patients and the model of obese rats to provide the new experimental basis for revealing the molecular mechanism of obesity and the diagnosis and treatment for obesity. The correlation between FAIM 1 expression and simple obesity was determined through testing the expression of FAIM 1 protein in white blood cells for 17 cases of normal individuals and 40 cases of obese patients. To further reveal the relationship between FAIM1 and the occurrence and development of simple obesity, the model of obese rats was established by using high-fat diet, and the body weight and blood glucose levels of obese and control rats were measured. The successfully constructed obese model rats and normal rats were fasted for 12 hours. Blood taken from heart were used to measure the change of total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C) after anesthetizing animals. The epididymal fat pad and perirenal fat weights of obese rats and control rats were analyzed. The expression changes of FAIM 1 and insulin receptor beta (IR β) protein were detected by Western-blot. The results showed the expression of FAIM1 protein in white blood cells of patients with simple obesity was reduced by 36.4% compared with normal control. Compared with the normal control rats, the serum levels of TC, TG and LDL-C in the obese model group were respectively increased by 37.1%, 25.6% and 39.1%, while HDL-C was reduced by 33.3%. The epididymal fat pad and perirenal fat weights of the obese model rats were respectively 1.85- and 2.24-fold of that in the normal control rats. Compared with the control group, the expression of FAIM 1 and IR β in the liver of obese rats were decreased by 45.9% and 32.6%, respectively, which was consistent with the results of clinical blood samples. The study displayed that the expression of FAIM 1 is significantly nagtively correlated with simple obesity, and FAIM 1 may be a new target for diagnosis and treatment for simple obesity.
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