一种新型金属化空心微球电磁功能材料

介绍了一种新型电磁功能材料．该材料由表面无电子镀镍的空心微球组成．采用扫瞄电镜观测了镀镍前后的表面微观结构，制备成样品放入X波段波导框中，在微波网络分析仪上进行散射参数测量，计算了电磁特性参数．结果表明，该材料在表面镀镍后取得了较高的磁导率(19．0)和磁损耗正切(0．6)，而介电常数保持较低(1．8)．与非金属化微球材料相比，可作为超薄型多层微波吸收材料的基本材料．     

结核病

结核病(Tuberculosis)是一种十分常见的传染病。据WHO报道，每年约有800万新病例发生，至少有300万人死于该病。我国解放前病死率达200～300人／10万，居各种病死原因之首。解放后，随着人民生活水平提高、卫生状况改善，特别是儿童普遍接种卡介苗，结核病的发病率与死亡率大大降低。但是，因艾滋病、吸毒、免疫制剂的应用、酗酒、贫困等原因，     

Influence of substrate surface morphology on wetting behavior of tracks during selective laser melting of aluminum-based alloys

AlSi12 samples were prepared by selective laser melting (SLM) under different processing conditions in order to obtain different top surface morphologies, where single tracks were produced using a fixed processing parameter to reveal the mechanism of the single track on different morphologies. The results show that the morphologies of single tracks changed with roughness of the top surface (Top R_a) of SLM parts, reflected in the variation of wetting angles on the surface processed previously as well as in dimensions of height, width, and depth at the cross-section of each single track. These changes were mainly caused by different wettability and flow behavior of the molten metal under various solidification environments of the single track during SLM. A poor solidification environment in which numerous balls existed limited an effective wetting behavior of molten metal on a previously processed surface of a SLM sample because of an increasing solid-liquid contact area, thus causing dramatical instability of the melt pool and attendant inferior processability of the single track. Meanwhile, under the action of surface tension, the molten metal had a high tendency to transfer into a pore near the single track to form an extending track or flow toward an upper region of melt to form a balling track, hence showing various morphologies of single tracks. This study proposes a theory of the solidification mechanism of single track on the non-ideal surface to provide a better understanding of the SLM processing of Al-Si alloy.     

网络时代教师面临的挑战--网上教学与传统课堂教学时间分配的对比

本文对网上教学与传统课堂教学环境中教师时间分配作了一个对比,并作了相关分析,提出在现代教学中教师必须掌握更多的知识与技能,迎接网络时代一场新的教育技术革命.     

现代食品检测技术课程项目化教学改革研究

简述了现代食品检测技术课程的概况,结合课程特点,将项目化教学引入现代食品检测技术课程教学中,打破传统的教学方法所遵循的理论讲解-实验操作的教学模式,教学质量和效率得到很大提升,以"原子吸收分光光度法在食品检测中的应用"项目为例,分析了项目教学法的具体设计与应用。     

谈大学生社会实践的几个问题

本文从社会实践教育是大学生教育过程中的重要组成部分这样一个基本原则出发,分析了社会实践教育的现实意义,论述了大学生社会实践的三种基本形式,阐明了社会实践活动中的组织管理与思想教育问题。     

我国高校科研傩制改革30年——成就与经验、问题与展望

改革开放30年,高校科研体制改革成就卓著,高校科研已经成为国家基础研究主力军和应用研究的重要方面军,其中的经验是丰富而宝贵的.梳理这30年的发展历程,总结改革和发展的成就与经验,分析其中的问题,是为了在新的历史起点上更好地深化改革,推动我国高校科研体制的进一步完善.     

幼儿园家长志愿者研究综述

幼儿园家长志愿者作为家长参与幼儿园活动的一种有效形式已经引起国内外研究者的关注.无论是从家长本身的需要角度还是从加强家长与教师的紧密关系、促进孩子更好发展的角度来看,家长志愿者参与幼儿园活动都具有重要意义.本文从家长志愿者的招募、培训、激励与评价等方面对国内外的相关研究进行概括与分析,以期对我国家园合作的实践提供一些启示.     

Immune recovery after fluid resuscitation in rats with severe hemorrhagic shock

Objective

To investigate the effects of resuscitation with normal saline (NS), hypertonic saline (HTS), and hydroxyethyl starch (HES) on regulatory T cells (Tregs), helper T 1 (Th1)/Th2 and cytotoxic T 1 (Tc1)/Tc2 profiles in the treatment of hemorrhagic shock.

Methods

Rats subjected to severe hemorrhagic shock were resuscitated for 30 min with NS (n=8), HTS (n=8), or HES (n=8); sham (n=8) and naive control (n=8) groups were used for comparison. Following fluid resuscitation, the whole shed blood was reinfused for 30 min, and the rats were observed with continuous hemodynamic monitoring for 120 min. CD4⁺CD25⁺Foxp3⁺ Treg proportions, Th1/Th2 and Tc1/Tc2 profiles in spleen were analyzed by three-color flow cytometry.

Results

The proportion of CD4⁺CD25⁺Foxp3⁺ Tregs and ratios of Th1/Th2 and Tc1/Tc2 did not differ among control, sham, and HTS groups, but were significantly lower in NS and HES groups (both P<0.05 vs. sham); NS and HES levels were similar. The level of Tc1 was significantly increased in HTS (P<0.05 vs. sham), and levels of Tc2 were increased in NS, HES, and HTS groups compared to sham (all P<0.05), but did not differ from each other.

Conclusions

HTS resuscitation has a greater impact on immune system recovery than NS or HES by preserving the proportion of Tregs and maintaining the balance between Th1/Th2 and Tc1/Tc2 cells in the spleen. Thus, HTS resuscitation provides potential immunomodulatory activity in the early stage after hemorrhagic shock.

     

连接光异构化非天然氨基酸的RGD肽抑制细胞的附着

利用固相肽合成方法 ,将带有光敏基团偶氮苯的非天然氨基酸———苯基偶氮苯基苯丙氨酸与RGD肽连接 ,得到具有光敏功能的RGD肽 .非天然氨基酸连接在C端的RGD肽与HeLa细胞表面的整合素有很强的结合能力 .RGD侧链上的光敏基团的光致异构化对RGD肽与HeLa细胞表面的整合素的结合有一定的影响