Subjects: Mechanics >> Applied Mechanics submitted time 2023-03-20 Cooperative journals: 《应用力学学报》
Abstract： The ice load is a key factor affecting the vibration response and fatigue life of wind turbinestructure in the Bohai Sea and the North Huanghai Sea of China. For the flexible monopile of wind tur-bine , the anti-ice cones installed on the structure at the water level can effectively reduce the ice load,which can ensure safe operation. To analyze the ice load of conical pile of wind turbine , the dilated poly-hedron based discrete element method ( DPDEM) is adopted to model the level ice and broken ice floes.The ice loads and ice-induced vibration of conical stnucture are simulated with various conical diametersand ice concentrations of broken ice field. The simulated results show that the ice loads of level ice andbroken ice perform the characteristics of randomness and periodicity. The ice load of level ice is obvioushigher than that of ice floes. The ice load of level ice on the upward cone is larger than that on the down-ward cone , while the ice load of broken ice on the upward cone is smaller than that on the downward cone.The study shows that the DPDEM can be applied to simulate the ice load on conical strnucture of wind tur-bine effectively. It can be applied to the ice-resistant structure design and safe operation of offshore coni-cal structures in ice-covered regions.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-12-01 Cooperative journals: 《中国全科医学》
Abstract：
Background China's national basic public health service provides free health examination services for the older adults aged 65 and above once a year, and health examination is the first step of "early detection, early diagnosis and early treatment" of common diseases in the older adults. The contribution of the older adults health examination service of basic public health services to the detection of health abnormalities in the older adults and the information of the older adults have been reported in less relevant studies. This paper mainly focuses on the abnormal detection rate of health examination of the older adults in basic public health services, and understands the effect of health examination for the older adults in the national basic public health service project from the perspective of the demand side. Objective Understand the abnormal detection rate in the health examination services provided by the basic public health service for the older adults over 65 years of age. Methods Multi-stage stratified sampling was used to take the older adults aged >=65 years old from 20 primary medical institutions in 3 provinces and 5 cities in the eastern, central and western regions of China as the survey subjects, and according to the basic public health management, they were divided into three categories: general older adults (not suffering from hypertension or diabetes), hypertension older adults and diabetic older adults people, and one-to-one questionnaire survey was conducted for all survey subjects. Results (1) The abnormal detection rate of health examination for the older adults was 67.4%, and the rural older adults were higher than those in urban areas (70.6%> 64.1%, P<0.001); (2) Abnormal blood pressure: the highest detection rate of abnormal physical examination in the older adults is abnormal blood pressure, 38.9% of the respondents self-reported abnormal blood pressure in the latest annual physical examination results, which is higher in rural areas than in urban areas (41.2%> 36.6%, P=0.010); 49.1% of the older adults who have been diagnosed with hypertension have abnormal blood pressure values in the annual physical examination, 36.1% of the older adults with diabetes have abnormal blood pressure values, and 18.3% of the general older adults have found abnormal blood pressure values in the latest physical examination. (3) Abnormal blood sugar: 24.8% of the respondents reported that they found abnormal blood glucose in the latest physical examination; The proportion of abnormal blood glucose in the older adults who have been diagnosed with diabetes is 60.5%, the abnormal blood glucose rate of the hypertensive older adults is 9.7%, and the screening rate of abnormal blood glucose in the general older adults is 8.4%. (4) The overall detection rate of anemia was 2.0%, and the older adults in rural areas were higher than those in urban areas (2.6% > 1.4%, P=0.021); The overall detection rate of fatty liver was 14.7%, and the urban older adults were higher than those in rural areas (17.2% > 12.3%, P<0.001). (5) Compared with the general older adults, the detection rate of abnormal blood pressure in the older adults with high blood sugar is 2.66 times, the detection rate of abnormal blood lipids in the older adults with hypertension and hyperglycemia is 1.64 and 1.41 times, the detection rate of overweight and obesity in the older adults with hypertension and hyperglycemia is 2.81 and 2.57 times, the detection rate of fatty liver in the older adults with hypertension and hyperglycemia is 2.10 and 1.52 times, respectively, and the detection rate of anemia in the older adults with hypertension and hyperglycemia is 0.26 and 0.50 times that of the general older adults; Compared with urban areas, the abnormal blood pressure, abnormal blood sugar and anemia of the rural older adults were 1.29, 1.36 and 1.76 times higher, respectively, while the detection rate of fatty liver among the rural older adults was 0.30 times. Conclusion The detection rate of abnormal blood pressure in the health examination is high, the blood pressure and blood sugar control of the older adults with hypertension and diabetes has improved, and the health prevention and treatment of the older adults in rural areas is not as good as that in cities.
Subjects: Geosciences >> Geography submitted time 2021-12-12 Cooperative journals: 《干旱区研究》
Abstract：研究极端暖事件，对于应对气候变化、制定防灾减灾政策具有重要的理论价值与实际意义。利用1961—2017年中国地面气温日值格点数据集和1961—2050年CMIP6气候模式数据，通过模拟精度验证，筛选出模拟效果较好模式进行多模式集合平均，采用气候倾向率和反距离加权法（IDW）对新疆过去及未来6—9月极端暖事件日数、频率和强度时空变化进行研究。结果表明：过去57 a，新疆极端暖事件日数、频率和强度呈增加趋势，倾向率分别为0.2 d·(10a)-1、0.02次·(10a)-1和0.04 ℃·(10a)-1；极端暖事件日数和频率的空间分布具有南疆高于北疆的特征，高发区为南疆西部，而强度则为北高南低的空间分布特征，高值区分布在北疆。未来33 a，在SSP245与SSP585情景下，新疆极端暖事件日数、频率和强度均呈显著增加趋势；相对于1961—2017年平均极端暖事件日数分别增加21 d和28 d，平均极端暖事件频率分别增加1.6次和1.8次，平均极端暖事件强度分别升高1.2 ℃和1.3 ℃，且SSP585情景下增速更显著；极端暖事件日数和频率高发区位于南疆中部，强度高发区仍在北疆；南疆极端暖事件日数、频率和强度增幅均大于北疆。伊朗副热带高压、西太平洋副热带高压位置的变化与土壤湿度变化会影响新疆极端暖事件的强弱。关键词：极端暖事件；多模式集合；时空变化；情景预估；新疆
Subjects: Geosciences >> Geography submitted time 2021-08-11 Cooperative journals: 《干旱区研究》
Abstract：为了解生态输水后地下水埋深和植被的变化，采用统计方法和遥感影像数据分析输水后孔雀河地下水埋深时空变化特征、地下水埋深和累积输水量的关系以及输水后NDVI和植被覆盖度的变化。结果表明：从时间变化来看，生态输水后孔雀河地下水埋深呈现稳步抬升趋势，年内地下水埋深变化主要受人类农业生产活动影响；从空间变化来看，垂直于河道方向上各断面地下水埋深的抬升幅度随距离的增加而减小，沿河道方向上，中游断面埋深抬升变化量最大；地下水埋深与累积生态输水量呈负相关，中游断面相关性最显著；2016—2019年上游和中游断面所在的研究河段NDVI分别增长了64.28%和100%，下游河段NDVI值稳定在0.05，距河道2 km范围内植被覆盖度呈增长趋势。生态输水对孔雀河流域地下水埋深和植被已产生积极作用，建议在未来的生态输水过程中保持合理输水量的同时，加强地下水监管力度，保护生态安全。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-27 Cooperative journals: 《干旱区研究》
Abstract：以砒砂岩为母质发育的栗钙土作为供试土壤，沙棘作为供试树种，基于茎热平衡法（SHB）在温室内研究不同灌水梯度下T1（田间持水量θFC25%）、T2（θFC40%）、T3（θFC55%）沙棘液流速率变化特征。采用HOBO小型气象站监测环境因子，研究沙棘液流速率对环境因子的响应关系。结果表明：① 沙棘液流速率除明显的昼夜变化外，还伴有“光合午休”现象，液流变化曲线呈双峰形；② 沙棘液流速率与土壤含水率呈正比，液流速率和日累积量为T1＜T2＜T3，其中，T2和T3差距较小；③ 沙棘液流速率与光合有效辐射、空气温度呈正相关，与空气湿度呈负相关；不同灌水梯度下液流速率与各环境因子的相关性绝对值表现为T1＜T3＜T2。回归方程R2表现为T1＜T3＜T2。T2梯度下沙棘液流速率处于较高水平，对环境因子响应程度最高，温度是影响沙棘液流速率变化的主导因子。
Subjects: Psychology >> Developmental Psychology submitted time 2018-12-26
Abstract： 为探究不同卷入情境下儿童基于资源价值的分配行为特点以及内群体偏爱在其中的作用，呈现给儿童两种实验情境：实验一，134名5~8岁儿童在第一方情境下与来自内、外群体的一名儿童分配不同价值的物品，结果发现7~8岁儿童公平分配比例与5~6岁儿童无显著差异；实验二，130名5~8岁儿童在第三方情境下给来自特定群体的两名儿童分配资源，结果发现7~8岁儿童公平分配比例显著高于5~6岁儿童。两个实验均发现儿童的分配行为表现出内群体偏爱，5~6岁儿童比7~8岁儿童更明显。并且，5~6岁女生比男生有更明显的内群体偏爱，但在7~8岁组无性别差异。此外，只有7~8岁儿童的公平分配行为表现出卷入情境上的差异，他们在第三方情境比第一方情境下更能做出公平分配，但5~6岁儿童的公平分配行为并无情境差异。综上可见，比起年幼儿童，年长儿童基于资源价值的公平行为发展得更好，并且在两种卷入情境下受内群体偏爱的影响均更小。
Subjects: Biology >> Bioengineering submitted time 2018-04-19 Cooperative journals: 《中国生物工程杂志》
Abstract：SpyCatcher和SpyTag可通过自发反应形成共价键，产生稳定的分子自组装体。酶分子自组装体因具有高效有序的催化特性在合成生物学和纳米技术领域具有重要的应用价值。为探索SpyTag/SpyCatcher在大肠杆菌胞内多酶复合体系形成有序自组装分子能力，将SpyCatcher和SpyTag分别与P450BM3m单加氧酶和葡萄糖脱氢酶GDH进行融合表达，以期产生具有辅酶再生循环系统、高效生物合成靛蓝分子的SpyTag/SpyCatcher双酶自组装复合体。首先，通过电泳及质谱对重组工程菌表达蛋白进行分析，证实SpyCatcher-P450BM3m与SpyTag-GDH在胞内成功形成了自组装多酶复合体；然后，系统分析了不同培养条件下组装体合成靛蓝的能力，结果发现，经0.5mmol/L IPTG诱导后，菌体在16 ℃继续培养18 h后，工程菌对吲哚（2 mmol/L）与葡萄糖（4 mmol/L）的全细胞催化能力最强，靛蓝产量最高达258 mg/L，是未组装多酶系统的1.9倍，比P450BM3m单酶表达系统高约2.4倍；反应70 min后达到反应平衡，转化率为52%。本研究成功实现了SpyTag/SpyCatcher介导的多酶体系在大肠杆菌细胞中的自组装和高效转化体系，为胞内多酶复合物组装体的设计提供了新思路。
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