不同接地体冲击接地阻抗的时域分析

用时域有限差分(FDTD)法对接地体冲击接地阻抗进行了时域分析.计算了脉冲泄流时不同接地体的冲击接地阻抗(TGR),并分析了接地体自身形状及电磁参数对TGR的影响.通过分析得到如下结论:在接地体上下表面埋深相同,表面积相同,但接地体形状不同时,TGR基本相同;体积相同,表面积越大,TGR越小,但用刻槽方法使表面积增大不能减小TGR;非金属接地体电导率足够大时具有与导体一样的泄流效果;接地体磁导率变化对TGR影响很小.     

Chenodeoxycholic Acid Has Non-Thermogenic,Mitodynamic Anti-Obesity Effects in an In Vitro CRISPR/Cas9 Model of Bile Acid Receptor TGR5 Knockdown

Bile acids (BA) have shown promising effects in animal models of obesity. However, the said effects are thought to rely on a thermogenic effect, which is questionably present in humans. A previous work has shown that the BA chenodeoxycholic acid (CDCA) can revert obesity and accelerate metabolism in animal and cell culture models. Thus, the aim of this study was to understand if this obesity reduction is indeed thermogenically-dependent. A CRISPR/Cas9 model of TGR5 (BA receptor) knockdown in 3T3-L1 adipocytes was developed to diminish thermogenic effects. Various parameters were assessed, including mitochondrial bioenergetics by Seahorse flux analysis, oxidative stress and membrane potential by fluorometry, intermediary metabolism by NMR, protein content assessment by Western Blot, gene expression by qPCR, and confocal microscopy evaluation of mitophagy. CDCA was still capable, for the most part, of reversing the harmful effects of cellular obesity, elevating mitophagy and leading to the reduction of harmed mitochondria within the cells, boosting mitochondrial activity, and thus energy consumption. In summary, CDCA has a non-thermogenic, obesity reducing capacity that hinges on a healthy mitochondrial population, explaining at least some of these effects and opening avenues of human treatment for metabolic diseases.     

Factors influencing thermal structure in a tributary bay of Three Gorges Reservoir

To better understand the factors influencing the thermal structure of tributaries in the Three Gorges Reservoir(TGR),a well validated three-dimensional hydrodynamic and water temperature model was proposed to simulate the water temperature distribution in the Xiangxi Bay, a representative tributary of TGR.The numerical results show that water temperature stratification seasonally occurred in the Xiangxi Bay, with stable vertical temperature profiles.It is found from the numerical experiments that three key factors are responsible for the formation of water temperature structure:(1) very often,the locations of thermocline are mainly determined by wind speeds, and the higher the wind speed is, the deeper the thermocline is located beneath the water surface,which could be expressed by a fitted exponential function,(2) the thermal structure is affected by static stability of water column, and the thermocline becomes closer to the water surface and its thickness increases with the increase of temperature, (3) due to the effect of the thermal density inflow, the water temperature of the hypolimnion tends to be uniform, however, even under the condition of larger inflow discharge,the influence of the inflow on the epilimnion and the thermocline is not significant.     

三峡水库动态汛限水位控制范围探讨

为了充分发挥三峡水库的防洪兴利效益,将当前单一汛限水位控制的运行方式改为动态汛限水位控制是必要的,也是可行的.在满足水库下游防洪标准和允许水库下泄安全流量要求的前提下,对主汛期和汛末期分别采用预泄方式和预蓄方式进行调洪演算,研究不同动态汛限水位控制范围的影响,得到了符合水库实际调度的动态汛限水位控制范围.结果表明,三峡水库实施动态汛限水位控制的运行方式,既可以避免抬高汛限水位引起的防洪风险,又能增加水库兴利效益.