绕扰流片分离流动的壁面压力测量

在风洞中用电子扫描阀进行测压实验，研究了底部间隙和锯齿高度对扰流片引起的壁面压力分布的影响。结果表明底部间隙在g／h≥1．0时对扰流片上游壁面压力分布曲线有较大影响，而对下游回流区压力分布曲线的影响主要在0≤g／h≤2．0的区域内；并且在g／^=0．2、1．0时，流动结构发生改变。另外，锯齿扰流片的当量面积与平板扰流片相等时，锯齿高度对下游底板压力分布特性的影响亦主要限于0≤x／h≤2．0的区域。     

Epidermal lipids

From the time an epidermal cell leaves the basal layer to the time it is desquamated, the cell lipids change dramatically, both qualitatively and quantitatively. The most abundant lipid class in basal cells is phospholipid with the remaining lipid being accounted for by roughly equal proportions of cholesterol, non-esterified fatty acid, triacylglycerol and glycolipid: minor components include cholesteryl esters and ceramide. In contrast, approximately half of the lipid in a desquamated cell consists of ceramide, with the remainder consisting largely of cholesterol and non-esterified fatty acid. Immediately before desquamation, small concentrations of cholesteryl sulphate and glycolipid have been found and there is evidence that these polar lipids are important components of the water barrier and also contribute towards the physical integrity of the lower part of the stratum corneum. The change in lipid content as cornification proceeds is no less dramatic than the change in lipid composition. A basal cell contains about 10 pg lipid, whereas a desquamated stratum corneum cell contains approximately six times this amount. The change in lipid composition of a cell undergoing cornification results, therefore, largely from de novo synthesis of lipid, especially cholesterol, non-esterified fatty acid and ceramide.
Les lipides de l'épiderme     

ZZS型钻井液自同步直线振动筛及其工作原理

介绍了ZZS型钻井液自同步直线振动筛的特点及性能，给出了该振动筛的简化力学模型，从力学角度分析了该振动筛的工作原理、动力学特性及自同步原理，提出直线筛工作时，直线振动条件是相位差角△α为零，若不满足该条件，振动将是直线振动与摇摆振动的组合。还推导了直线筛自同步条件，两电动机特性愈接近，其摩擦阻矩愈接近相等，两筛愈容易实现同步运转。     

静电除尘振打系统的技术改进

根据静电除尘振打系统的结构，建立振动模型，应用机械振动理论进行原理分析，找出相关因素。据此进行改进方案分析，并提出以改进极板自然频率为主要措施的实施方法，使静电除尘振打系统结构合理，从而延长静电除尘装置的使用寿命。     

钻井液振动筛传动方式初探

钻井液振动筛大都为惯性振动筛，按筛箱振动型式分有圆型振动筛、直线型振动筛和椭圆型振动筛。由于激振器与筛箱一起参振，激振器与动力机之间必须采用常规的万向节或柔性带实现动力传递。为克服常规的万向节、柔性带传动的传动链长、结构复杂和易损坏等缺点，提出采用胶带直接驱动代替常规的万向节或柔性带传动，并在激振器胶带轮和传动方式上作一定改变，便可满足使用要求。这种传动方式具有传递可靠和结构简单等优点，已成功地应用于2ZZS－T直线型振动筛上，使用效果良好。     

IgG and IgA with Potential Microbial-Binding Activity Are Expressed by Normal Human Skin Epidermal Cells

The innate immune system of the skin is thought to depend largely on a multi-layered mechanical barrier supplemented by epidermis-derived antimicrobial peptides. To date, there are no reports of antimicrobial antibody secretion by the epidermis. In this study, we report the expression of functional immunoglobulin G (IgG) and immunoglobulin A (IgA), previously thought to be only produced by B cells, in normal human epidermal cells and the human keratinocyte line HaCaT. While B cells express a fully diverse Ig, epidermal cell-expressed IgG or IgA showed one or two conservative V_HDJ_H rearrangements in each individual. These unique VDJ rearrangements in epidermal cells were found neither in the B cell-derived Ig VDJ databases published by others nor in our positive controls. IgG and IgA from epidermal cells of the same individual had different VDJ rearrangement patterns. IgG was found primarily in prickle cells, and IgA was mainly detected in basal cells. Both epidermal cell-derived IgG and IgA showed potential antibody activity by binding pathogens like Staphylococcus aureus, the most common pathogenic skin bacteria, but the microbial-binding profile was different. Our data indicates that normal human epidermal cells spontaneously express IgG and IgA, and we speculate that these Igs participate in skin innate immunity.     

Starting to Gel: How Arabidopsis Seed Coat Epidermal Cells Produce Specialized Secondary Cell Walls

For more than a decade, the Arabidopsis seed coat epidermis (SCE) has been used as a model system to study the synthesis, secretion and modification of cell wall polysaccharides, particularly pectin. Our detailed re-evaluation of available biochemical data highlights that Arabidopsis seed mucilage is more than just pectin. Typical secondary wall polymers such as xylans and heteromannans are also present in mucilage. Despite their low abundance, these components appear to play essential roles in controlling mucilage properties, and should be further investigated. We also provide a comprehensive community resource by re-assessing the mucilage phenotypes of almost 20 mutants using the same conditions. We conduct an in-depth functional evaluation of all the SCE genes described in the literature and propose a revised model for mucilage production. Further investigation of SCE cells will improve our understanding of plant cell walls.     

带蒂胸大肌肌皮瓣修复口底癌术后缺损的应用

目的探讨口底癌手术后大型组织缺损采用带蒂胸大肌肌皮瓣修复的可行性及疗效。方法对10例临床Ⅲ期和Ⅳ期的口底癌患者大型组织缺损经带蒂胸大肌肌皮瓣修复后的临床资料进行回顾性分析。结果 10例口底癌患者手术后的缺损均成功以带蒂胸大肌肌皮瓣修复,9例患者皮瓣全部成活,1例皮瓣部分边缘有坏死,伤口经换药后愈合。结论带蒂胸大肌肌皮瓣是口底癌术后缺损的良好修复组织,手术操作、全身情况、吸烟酗酒等因素是影响胸大肌肌皮瓣成功的关键因素。     

Gust alleviation using rapidly deployed trailing-edge flaps

This paper presents the results of a numerical and experimental investigation into the use of a small, rapidly actuated, actively controlled trailing-edge flap (4% chord) to alleviate the unsteady loading experienced by wind turbine blades due to atmospheric turbulence and the atmospheric boundary layer.The computational investigation demonstrated that the rejection of realistic flow disturbances should be feasible with the use of load measurements on the blade and the feedback control of a small flap. The experimental prototype subsequently successfully rejected intentionally introduced flow disturbances from the vortex street of a square block located upstream of a sting-mounted, strain-gauged wing fitted with flap. This application of control provided a very significant reduction in the unsteady loading experienced (∼81% of C_LRMS).The findings show the potential of this method of load control for the rejection of unsteady aerodynamic loading by the sole use of load measurements from the wing for simple feedback control (PID/LQG).     

折叠带蒂髂腹股沟皮瓣修复手掌洞穿性缺损的围手术期护理

目的探讨带蒂髂腹股沟皮瓣折叠修复手掌洞穿性缺损的围手术期护理。方法2004～2008年,12例手掌洞穿性缺损应用带蒂髂腹股沟皮瓣折叠修复,采取心理护理、皮瓣受区、皮瓣供区准备、皮瓣血运监测、皮瓣固定护理、体位护理、饮食控制等围手术期护理。结果皮瓣全部成活,康复顺利,无并发症发生。结论该围手术期系统护理策略对带蒂髂腹股沟皮瓣折叠修复方法修复手掌洞穿性缺护理是安全有效的护理方法。