Dynamic “Molecular Portraits” of Biomembranes Drawn by Their Lateral Nanoscale Inhomogeneities

To date, it has been reliably shown that the lipid bilayer/water interface can be thoroughly characterized by a sophisticated so-called “dynamic molecular portrait”. The latter reflects a combination of time-dependent surface distributions of various physicochemical properties, inherent in both model lipid bilayers and natural multi-component cell membranes. One of the most important features of biomembranes is their mosaicity, which is expressed in the constant presence of lateral inhomogeneities, the sizes and lifetimes of which vary in a wide range—from 1 to 10³ nm and from 0.1 ns to milliseconds. In addition to the relatively well-studied macroscopic domains (so-called “rafts”), the analysis of micro- and nanoclusters (or domains) that form an instantaneous picture of the distribution of structural, dynamic, hydrophobic, electrical, etc., properties at the membrane-water interface is attracting increasing interest. This is because such nanodomains (NDs) have been proven to be crucial for the proper membrane functioning in cells. Therefore, an understanding with atomistic details the phenomena associated with NDs is required. The present mini-review describes the recent results of experimental and in silico studies of spontaneously formed NDs in lipid membranes. The main attention is paid to the methods of ND detection, characterization of their spatiotemporal parameters, the elucidation of the molecular mechanisms of their formation. Biological role of NDs in cell membranes is briefly discussed. Understanding such effects creates the basis for rational design of new prospective drugs, therapeutic approaches, and artificial membrane materials with specified properties.     

How Cancer Cells Invade Bladder Epithelium and Form Tumors: The Mouse Bladder Tumor Model as a Model of Tumor Recurrence in Patients

Non-muscle-invasive bladder cancer is the most common form of bladder cancer. The main problem in managing bladder tumors is the high recurrence after the transurethral resection of bladder tumors (TURBT). Our study aimed to examine the fate of intravesically applied cancer cells as the implantation of cancer cells after TURBT is thought to be a cause of tumor recurrence. We established an orthotopic mouse bladder tumor model with MB49-GFP cancer cells and traced them during the first three days to define their location and contacts with normal urothelial cells. Data were obtained by Western blot, immunolabeling, and light and electron microscopy. We showed that within the first two hours, applied cancer cells adhered to the traumatized epithelium by cell projections containing α3β1 integrin on their tips. Cancer cells then migrated through the epithelium and on day 3, they reached the basal lamina or even penetrated it. In established bladder tumors, E-cadherin and desmoplakin 1/2 were shown as feasible immunohistochemical markers of tumor margins based on the immunolabeling of various junctional proteins. Altogether, these results for the first time illustrate cancer cell implantation in vivo mimicking cellular events of tumor recurrence in bladder cancer patients.     

六水氯化镁在六种多元醇中溶解度的测定和关联

六水氯化镁的溶解度是镁盐综合利用的重要基础数据。采用静态平衡法测定了六水氯化镁在1,2-丙二醇、1,3-丙二醇、1,3-丁二醇、一缩二乙二醇、二缩三乙二醇、一缩二丙二醇6种多元醇中的溶解度（278.15~328.15 K）。实验结果表明,六水氯化镁在6种多元醇中的溶解度均随着温度的升高而增大,其中在一缩二乙二醇中的溶解度最大,在二缩三乙二醇中的溶解度随着温度的变化较其他多元醇变化更为明显。使用Apelblat方程、λh方程、Van′t Hoff方程和多项式方程对溶解度数据进行了关联,结果良好,其中Apelblat方程和多项式方程拟合结果优于其他方程。利用Van′t Hoff方程计算了6种体系的溶解焓、溶解熵和吉布斯自由能。这些结果对镁盐的分离提取及镁基功能材料的制备具有重要的参考价值。     

微电网跟踪调度计划双层双时间尺度实时控制策略

为了提升微电网跟踪调度计划的能力,并降低分布式电源和负荷的功率波动对跟踪效果的影响,提出一种利用由超级电容和电池储能组成的混合储能系统跟踪调度计划的双层双时间尺度实时控制策略。上层基于模型预测控制方法建立日内滚动优化模型,结合分布式电源和负荷的超短期功率预测结果,综合考虑一段时域内的跟踪偏差及混合储能系统的功率和荷电状态对跟踪调度计划进行滚动优化;下层在上层优化结果的基础上,采用基于荷电状态的混合储能系统实时控制策略对超级电容和电池储能的实时功率进行协调分配,进一步降低分布式电源和负荷的实时功率波动对跟踪效果的影响。通过仿真算例对所提控制策略进行验证,结果表明:所提策略不但实现了良好的实时跟踪调度计划的控制效果,而且优化了超级电容和电池储能的荷电状态。     

考虑样本类别不平衡的电网故障事件智能识别方法

电网中不同设备的故障概率存在差异,影响智能诊断技术的准确性.为解决此问题,提出了一种基于代价敏感学习和模型自适应选择融合的电网故障事件智能识别方法.首先,利用Word2vec模型将预处理后的电网告警信息向量化,并搭建2个双向长短期记忆网络作为基础分类器;然后,设计代价敏感损失函数,将交叉熵损失函数与代价敏感损失函数分别应用于2个分类器中;最后,提出一种模型自适应选择融合法,融合上述分类器,得到故障事件识别结果.实际数据测试表明,所提方法能够有效降低故障事件识别中样本类别不平衡的影响.     

基于模型预测控制算法的多风储直流微电网分布式电压二次控制策略

针对含多组风储单元的直流微电网中蓄电池的电压优化控制问题,提出了一种基于模型预测控制算法的分布式电压二次控制策略.设计了一种多步长预测一致性模型作为电压预测模型,通过目标函数最小化求解预测系数,得到最优电压二次控制补偿量加入一次控制中,将传统一致性算法中比例积分控制器下的偏差调节问题转化为模型预测控制器下的电压跟踪问题进行求解,从而实现对直流母线电压动态响应的滚动优化.该方法有效解决了传统一致性算法下电压控制策略瞬态特性差和部分工况下存在控制误差等问题,并通过MATLAB/Simulink仿真平台搭建模型验证了不同工况下所提策略的有效性和优越性.     

Sulfuric acid recovery from rare earth sulphate solutions by diffusion dialysis

1 Introduction As an important industrial chemical, sulfuric acids are widely used in metallurgical and chemical processes, in which some waste solutions containing free sulfuric acids and metallic ions are therefore produced[1, 2]. If these waste acids …     

自动壳封焊机焊缝位置控制的实验研究

为解决自动壳封焊机机械凸轮式仿形的缺点，提出了基于电子凸轮的控制方案，为实现电子凸轮控制方案，在焊接轨迹形成分析的基础上，建立了焊枪位置控制的数学模型，改进后的自动焊机焊接试验表明，焊接位置误差较小，可以满足生产的需要。     

5%Si高硅奥氏体不锈钢元素偏析及均匀化处理

 高硅奥氏体不锈钢由于高含量硅元素的加入使其具有优异的耐高温腐蚀性能和较低的成本,在制酸行业有着潜在的应用价值。然而,该合金中高含量硅元素的加入会促进凝固过程中溶质再分配,进而造成显著的元素偏析,最终导致合金内部产生枝晶组织和大量的有害相。对铸锭组织进行均匀化处理能够有效消除枝晶与元素偏析,促进析出相回溶和枝晶消融,从而改善材料的热塑性,有效应对热变形开裂问题。因此,采用金相显微镜(OM)、扫描电镜能谱分析(SEM/EDS)、电子探针(EPMA)、JMatPro软件计算等方法,研究了实验室条件下制备的5%Si高硅奥氏体不锈钢铸锭的显微组织和元素分布状态,通过残余偏析指数、扩散动力学计算并结合均匀化处理试验验证,最终确定了5%Si高硅奥氏体不锈钢合理的均匀化处理工艺。结果表明,5%Si高硅奥氏体不锈钢凝固过程中钼元素偏析最为严重,通过残余偏析指数模型计算得到的均匀化动力学方程可用来指导该成分合金的均匀化处理工艺;5%Si高硅奥氏体不锈钢经过1 150 ℃×12 h均匀化处理后,铸锭内枝晶消融,元素偏析基本消除,析出相与铁素体回溶到基体中,合金转变为全奥氏体组织,热塑性得到改善;当加热温度达到1 250 ℃时,合金出现过烧现象,晶界开始熔化。     

基于RHT模型双孔同时爆破均质岩体损伤的数值模拟

为探究双孔爆破时炮孔间距和额外自由面对爆破过程中爆破损伤的影响,基于RHT（Riedel-Hiermaier-Thoma）损伤本构建立了多组三维数值模型,利用模型损伤云图研究不同爆破条件下的岩石爆破过程,通过自定义变量—有效损伤率的变化探究炮孔周围岩石损伤的时空演化过程。结果表明：随着炮孔间距的增加,岩石有效损伤率逐渐递减,相同截面处的有效损伤率在炮孔间距最小的方案中最大,相邻炮孔间的爆破能量叠加作用随炮孔间距的增大而减弱,合适的炮孔间距可以获得更加理想的爆破效果;岩石有效损伤率随着自由面到炮孔中心处距离的增大而逐渐减小,爆破能量倾向于向自由面方向传播,额外自由面对爆破能量分布的影响随自由面与炮孔间距的增大而减弱。数值模拟结果对研究双孔爆破能量的传递法则具有一定的借鉴意义。