ApoA1 Deficiency Reshapes the Phenotypic and Molecular Characteristics of Bone Marrow Adipocytes in Mice

In the present study, we studied the effect of apolipoprotein A-1 (APOA1) on the spatial and molecular characteristics of bone marrow adipocytes, using well-characterized ApoA1 knockout mice. APOA1 is a central regulator of high-density lipoprotein cholesterol (HDL-C) metabolism, and thus HDL; our recent work showed that deficiency of APOA1 increases bone marrow adiposity in mice. We found that ApoA1 deficient mice have greatly elevated adipocytes within their bone marrow compared to wild type counterparts. Morphologically, the increased adipocytes were similar to white adipocytes, and displayed proximal tibial-end localization. Marrow adipocytes from wild type mice were significantly fewer and did not display a bone-end distribution pattern. The mRNA levels of the brown/beige adipocyte-specific markers Ucp1, Dio2, Pat2, and Pgc1a; and the expression of leptin were greatly reduced in the ApoA1 knock-out in comparison to the wild-type mice. In the knock-out mice, adiponectin was remarkably elevated. In keeping with the close ties of hematopoietic stem cells and marrow adipocytes, using flow cytometry we found that the elevated adiposity in the ApoA1 knockout mice is associated with a significant reduction in the compartments of hematopoietic stem cells and common myeloid, but not of the common lymphoid, progenitors. Moreover, the ‘beiging’-related marker osteopontin and the angiogenic factor VEGF were also reduced in the ApoA1 knock-out mice, further supporting the notion that APOA1—and most probably HDL-C—regulate bone marrow microenvironment, favoring beige/brown adipocyte characteristics.     

HDPE在高压毛细管挤出过程中的温度窗口效应

对三种不同类型高密度聚乙烯(HDPE)进行高压毛细管挤出,均发现特殊的温度窗口效应,线性均聚5000S在v=8mm/min时的温度窗口为145℃~150℃;己烯共聚HXM TR-571在v=1mm/min时的窗口为150℃~153℃;双峰型GC100S在v=5mm/min的窗口为143℃~145℃,温度窗口内挤出压力骤降至最小值,挤出平稳,挤出物表面光滑,避免了压力振荡和变形,窗口与PE的分子量、支化度和柱塞速率有关。效应产生的原因是在温度窗口内发生了PE晶形相转变。不同挤出温度挤出物的差示扫描量热(DSC)分析表明,HXM TR-571和GC100S在窗口温度下挤出物具有较高的结晶温度(Tc)和较低熔点(T(m 2))。     

偶氮染料:新型高密度、多功能光盘存储介质

偶氮染料在短波区具有优良的光学和热学性质以及光致顺反异的特性,既是一类新型高密度可录光盘存储介质,又是一类可望作为可擦重写的光盘存储介质。本文在总结近几年最新研究成果的基础上,分别阐述了偶氮染料作为高密度可录光盘和可擦重写光盘存储介质的作用机理以及对记录介质的基本要求,讨论了影响偶氮染料光学、热学性质以及光存储性能的主要因素,并对未来的发展趋势作了展望。     

Research of Application of Passive Natural Ventilated Strategies of High-Density Urban Area

High-density development is becoming an inevitable tendency in Chinese urbanization. In this study, the application of natural ventilation in high-density urban development is discussed. Based on the domestic and foreign study on natural ventilation, indoor and outdoor natural ventilated strategies, and the application on natural ventilation in underground space development are analyzed. From the study, the relationship between passive and active ventilated technologies is interpreted into what is described to be synergistic, complementary and additive.     

采用截面流量统计的高密度人群行人计数

利用摄像头实现行人计数在智能视频监控领域有着重要的价值,但是行人互相遮挡、噪声、摄像机透视效果和图像背景等问题影响了人群计数的准确性.针对高密度人群场景的行人计数准确率的问题,提出了基于截面流量统计的行人计数方法,该方法基于梯度运动历史图像检测前景,并用有效运动图像改进了基于特征提取的行人计数方法,结合运动速度提取方法实现了行人计数.实验结果表明,提出的计数方法在高密度人群场景中具有较高的准确率和实时性,是一种针对高密度人群有效的行人计数方法.     

高密度烃燃料合成进展

总结了液体高密度烃燃料合成的最新进展,从原料、合成路线、使用性能等方面评价了多环高密度烃、高张力笼状烃、纳米添加剂等的优缺点及发展前景,分析了高密度烃燃料合成中存在的问题,介绍了作者所在课题组在此领域的工作进展。     

乳酸菌高密度培养条件优化研究

该试验通过单因素试验和响应面试验探究了乳酸菌高密度培养过程中碳酸钠缓冲盐添加时间、培养pH值、营养因子添加量以及后发酵时间对菌落总数的影响。结果表明，乳酸菌高密度培养的最优条件为接种量3%，培养温度42 ℃，培养2 h时添加15%碳酸钠缓冲盐，将pH调为6.5，同时添加与原发酵培养基等体积的营养因子（乳清∶番茄汁∶胡萝卜汁∶牛奶=4∶6∶6∶5）后再培养4 h。在此优化条件下，培养液的活菌数较高，为5.68×1011 CFU/mL。     

Molecular fractionation in melt-crystallized polyethylene: 4. Fracture

The macroscopically brittle fracture of five high-density polyethylenes subjected to different constant uniaxial tensile loads was studied by s.e.m. fractography on both untreated and solvent-etched samples. The low molecular weight systems showed three types of fracture propagation: interspherulitic propagation with and without reorientation and trans-spherulitic interlamellar propagation. There is evidence that the development of fracture is associated with a strength distribution in the structure caused by molecular weight segregation occurring during solidification of the samples.