Fair‐Weather Friends: Evidence of Lipoxin Dysregulation in Neurodegeneration

Lipoxins (LXs) are autacoids, specialized proresolving lipid mediators (SPMs) acting locally in a paracrine or autocrine fashion. They belong to a complex superfamily of dietary small polyunsaturated fatty acid (PUFA)–metabolites, which direct potent cellular responses to resolve inflammation and restore tissue homeostasis. Together, these SPM activities have been intensely studied in systemic inflammation and acute injury or infection, but less is known about LX signaling and activities in the central nervous system. LXs are derived from arachidonic acid, an omega‐6 PUFA. In addition to well‐established roles in systemic inflammation resolution, they have increasingly become implicated in regulating neuroinflammatory and neurodegenerative processes. In particular, chronic inflammation plays a central role in Alzheimer's disease (AD) etiology, and dysregulated LX production and activities have been reported in a variety of AD rodent models and clinical tissue samples, yet with complex and sometimes conflicting results. In addition, reduced LX production following retinal injury has been reported recently by the authors, and an intriguing direct neuronal activity promoting survival and homeostasis in retinal and cortical neurons is demonstrated. Here, the authors review and clarify this growing literature and suggest new research directions to further elaborate the role of lipoxins in neurodegeneration.     

PP－g－AA的制备和表征

用熔融接枝方法制备了聚丙烯－ｇ－丙烯酸（ＰＰ－ｇ－ＡＡ）。用光电子能谱，广角Ｘ射线衍射，红外光谱和化学滴定方法对接枝物进行了定性和定量表征。讨论了单体和引发剂浓度对接枝率的影响，确定了用红外光谱法测定接枝物含量的经验公式     

Biaxiale Ermüdung reibrührgeschweißter Strukturelemente

Biaxial fatigue of friction stir welded stiffened panels Within the framework of the European WelAir project, cruciform specimens made from stiffening FSW overlap joints were fatigued in the DLR biaxial test rig. To resemble the loading situation of pressurized fuselage structures, proportional loading without any phase shift, but with different load ratios λ between the loading components in both directions was applied.Natural crack initiation and subsequent crack growth were governed by the stiffness gradient caused by introducing the stringer. Cracks initiated and propagated at run‐in and run‐out locations in a direction perpendicular to the weld seam. The shortest fatigue life was observed for uniaxial loading in welding direction (λ = 0). An additional stress component perpendicular to the joint line (λ > 0) resulted in a higher number of cycles to failure. Similar to single stringer panels, increasing the load ratio also increased the number of cycles to failure for FSW clip‐stringer structural members, but additionally gives a different location of the fatal crack.     

疏水缔合AM/C10AM/AMPS三元共聚物的合成与盐水溶液粘度性能

采用胶束氧化还原聚合方法合成了AM/C10AM/AMPS三元疏水缔合共聚物。简介了合成过程,给出了主要的合成参数。保持其他合成条件不变,分别改变疏水单体N 癸基丙烯酰胺C10AM和阴离子单体2 丙烯胺基 2 甲基丙磺酸AMPS在单体总量中的摩尔百分数(0～1.5%和15%～40%),得到了16个共聚物,在45℃、3.67和7.34s-1下测定了用矿化度4000mg/L的模拟大庆盐水配制的1000mg/L共聚物溶液的粘度,讨论了引起粘度变化的原因。有7个样品的粘度能满足大庆油田聚合物驱油的要求(7.34s-1下的粘度大于40mPa·s),其中由1.2%C10AM、35%AMPS及AM合成的共聚物样品粘度最高(61.5mPa·s)。对共聚温度等合成条件的影响作了一般性的讨论。表1参6。     

μC／OS—Ⅲ在Cortex—M3处理器上的移植

为了将μC／OS-Ⅲ移植到Cortex—M3处理器上,选用RealView MDK作为软件开发平台,针对Cortex—M3处理器特性编写了移植所需的C语言和汇编语言源代码,并验证了移植的正确性。移植后的μC／OS-Ⅲ能够稳定运行于Cortex～M3处理器上。该移植对大部分Cortex—M3处理器具有通用性,对其他架构处理器的μC／OS-Ⅲ移植具有参考作用。     

Effect of atmospheric pollutants on the corrosion of high power electrical conductors: Part 1. Aluminium and AA6201 alloy

The aim of this study was to evaluate the joint effect of marine and industrial pollutants on the atmospheric corrosion of aluminium and its AA6201 alloy. Weight loss was determined after 4, 11, 16 and 24 months exposure being morphology and attack intensity analysed through SEM-EDX. Both materials showed the most intense attack for the highest SO₂ contents. Good correlation among weight loss, attack depth and tensile strength to rupture with time and with pollutant contents was determined for both materials in most sites. The cause for low aggressiveness of the heaviest Cl⁻ polluted atmosphere on aluminium was electrochemically demonstrated.     

Influence of the aluminum surface on the final results of a two-step anodizing

1050 Aluminum alloy sheets were used to analyze the influence of a surface treatment on the characteristics of the alumina layer formed in a two-step anodizing. The study was mainly focused on two pretreatment steps, electropolishing and acid etching, as well as on the intermediate stripping step. The pretreatment procedure was optimized by accounting for the chemical nature of the substrate, with the results indicating that additional pretreatment steps enhanced the self-ordered porous arrangement. The E-t curves recorded during the experiments demonstrated that the best alumina layers were obtained when the first barrier layer had a high resistance; i.e., a high anodizing potential. The application time of the stripping step was optimized to clean the surface from alumina remains, without damaging the aluminum substrate. By optimizing all of these experimental conditions, we were able to obtain porous anodic aluminum oxide layers displaying ordered domains several hundreds of nanometers in length.     

VAc/AA改性的VAE乳液高速接嘴卷烟胶的研制

介绍了VAc/AA改性的VAE乳液高速接嘴卷烟胶的制备方法。研究了各种因素对胶粘剂性能的影响。结果表明 :VAc/AA用量增加 ,VAE乳液的粘接性能增强。选择与VAE乳液相适应的乳化剂和控制适宜的pH值 ,可以增加VAE乳液的稳定性。采用滴加引发剂和混合单体的方法 ,可以避免过速反应产生及大粒径胶粒生成     

微波诱导稀土复合固体超强酸SO4^2-／ZrO2-Nd2O3催化合成乙酸苄酯

以新型稀土复合固体超强酸为催化剂，在微波辐射下苯甲醇和乙酸反应合成了乙酸苄酯，探索反应各因素对酯化率的影响。实验结果表明：SO4^2-／ZrO2-Nd2O3具有较高的催化活性。最佳反应条件为：醇酸摩尔比2．0（乙酸用量为0．2mol前提下），催化剂用量为1．8g，带水剂环己烷12mL，微波辐射功率550W，辐射时间25min，酯化率可达96．3％。该催化剂易于回收且可重复使用，具有良好的活性稳定性。     

牙膏胶黏剂单体AMPS的合成工艺

2-丙烯酰胺基-2-甲基丙磺酸（简称AMPS）是优秀的功能高分子材料的单体，其均聚物作牙膏胶黏剂，尤其是加盐牙膏，分散性好，稳定性高。本文研究了AMPS的合成工艺，采用丙烯腈、异丁烯和发烟硫酸为原料，一步合成AMPS，考察了反应物的配比、三氧化硫的浓度、反应温度、反应时间等对产品收率的影响。实验结果表明：当丙烯腈：异丁烯：发烟硫酸=5：1：1（摩尔比），三氧化硫质量分数10％（质量），反应温度20℃，反应时间2h，可得AMPS的收率为90％（质量），产品纯度99％（质量）左右。在最佳工艺条件下合成的AMPS产品为白色粉末，纯度99．1％（质量），熔点187℃，酸值270．7mgKOH／g，Fe离子含量小于0．0003％（质量）。