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31.
随着太赫兹技术的发展,太赫兹传输波导器件的研究成为待解决的重要问题之一。太赫兹波位于微波与红外光之间,寻找高效的传输、耦合器件一直是研究人员的目标。主要介绍了太赫兹传输波导研究现状,并总结了各类型太赫兹波导的优势与不足。根据材料与结构分别对金属波导、介质波导的研究进展进行了分析。其中金属波导包括裸金属线波导、微结构波导、空芯波导以及平板波导,介质波导包括介质空芯波导、多孔芯波导以及微结构波导。最后分别对太赫兹传输波导未来需要解决的研究方向进行了展望。  相似文献   
32.
Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in reproductive-aged women, and it typically involves elevated androgen levels. Recently, it has been reported that human bone marrow mesenchymal stem cells (hBM-MSCs) can regulate androgen synthesis pathways. However, the details of the mechanism are still unclear. hBM-MSC-derived secreted factors (the secretome) are promising sources of cell-based therapy as they consist of various types of proteins. It is thus important to know which proteins interact with disease-implicated biomolecules. This work aimed to investigate which secretome components contain the key factor that inhibits testosterone synthesis. In this study, we fractionated hBM-MSC-conditioned media into three fractions based on their molecular weights and found that, of the three fractions, one had the ability to inhibit the androgen-producing genes efficiently. We also analyzed the components of this fraction and established a protein profile of the hBM-MSC secretome, which was shown to inhibit androgen synthesis. Our study describes a set of protein components present in the hBM-MSC secretome that can be used therapeutically to treat PCOS by regulating androgen production for the first time.  相似文献   
33.
Adiponectin administration to pregnant mice decreases nutrient transport and fetal growth. An adiponectin deficiency, on the other hand, as seen in obese women during pregnancy, alters fetal growth; however, the mechanism is unclear. To determine the role of adiponectin on placenta function and fetal growth, we used adiponectin knockout, adiponectin heterozygote that displays reduced adiponectin levels, and wild-type mice on a control diet or high fat/high sucrose (HF/HS) diet. Triglycerides (TGs) in the serum, liver, and placenta were measured using colorimetric assays. Gene expression was measured using quantitative RT-PCR. Adiponectin levels did not affect fetal weight, but it reduced adiponectin levels, increased fetal serum and placenta TG content. Wildtype dams on a HF/HS diet protected the fetuses from fatty acid overload as judged by increased liver TGs in dams and normal serum and liver TG levels in fetuses, while low adiponectin was associated with increased fetal liver TGs. Low maternal adiponectin increased the expression of genes involved in fatty acid transport; Lpl and Cd36 in the placenta. Adiponectin deficiency does not affect fetal growth but induces placental dysfunction and increases fetal TG load, which is enhanced with obesity. This could lead to imprinting effects on the fetus and the development of metabolic dysfunction in the offspring.  相似文献   
34.
Mitochondria play a crucial role in cell physiology and pathophysiology. In this context, mitochondrial dynamics and, subsequently, mitochondrial ultrastructure have increasingly become hot topics in modern research, with a focus on mitochondrial fission and fusion. Thus, the dynamics of mitochondria in several diseases have been intensively investigated, especially with a view to developing new promising treatment options. However, the majority of recent studies are performed in highly energy-dependent tissues, such as cardiac, hepatic, and neuronal tissues. In contrast, publications on mitochondrial dynamics from the orthopedic or trauma fields are quite rare, even if there are common cellular mechanisms in cardiovascular and bone tissue, especially regarding bone infection. The present report summarizes the spectrum of mitochondrial alterations in the cardiovascular system and compares it to the state of knowledge in the musculoskeletal system. The present paper summarizes recent knowledge regarding mitochondrial dynamics and gives a short, but not exhaustive, overview of its regulation via fission and fusion. Furthermore, the article highlights hypoxia and its accompanying increased mitochondrial fission as a possible link between cardiac ischemia and inflammatory diseases of the bone, such as osteomyelitis. This opens new innovative perspectives not only for the understanding of cellular pathomechanisms in osteomyelitis but also for potential new treatment options.  相似文献   
35.
This study describes the development process of Kor-Factor, which is a novel composite evaluation index that was developed to promote Korean domestic academic journals. As more data accumulate, the Kor-Factor’s optimization process was modified in an attempt to address possible drawbacks of the original form; the result is presented in this study. This study compares Kor-Factor with the Impact Factor, which is the most well-known single element evaluation index. We found that Kor-Factor demonstrates a better power of differentiation and a greater capacity to reflect the reputability of key journals. The modified Kor-Factor, which has been developed through an optimization process, reveals a greater power of differentiation than the original Kor-Factor; however, the modified version has less capacity to reflect reputability. The evaluation elements of the modified Kor-Factor are better and are more evenly reflected on the index value than those of the original version. Finally, we propose the establishment of an appropriate data measurement period for the actual application of the index.  相似文献   
36.
凝汽器管板和水室的防腐   总被引:1,自引:0,他引:1  
根据凝汽器水室和管板的腐蚀机理,提出用环氧煤沥青做防腐涂层。本文介绍了环氧煤沥青的主要成分、性能以及凝汽器用环氧煤沥青防腐的施工工艺及涂层质量的检测方法等。  相似文献   
37.
We propose a new arbitration method for an input buffered switch with a buffered crossbar. In the proposed method, an exhaustive polling method is used to decrease the synchronization. Using an approximate analysis, we explain how the proposed method improves the switch performance. Also, using computer simulations, we show the proposed method outperforms the previous methods under burst traffic.  相似文献   
38.
面向服务的综合电子信息系统软件策略   总被引:1,自引:0,他引:1  
针对SOA在综合电子信息系统中的应用,介绍了SOA的概念,分析了应用需求,研究了基于SOA的系统软件结构和主要特征;从标准化、构件化、工具化、数据模型、服务总线、治理和管理等方面提出了SOA软件发展策略;探索了SOA软件的实现方法.  相似文献   
39.
基于Matlab/Simulink的电路分析   总被引:2,自引:0,他引:2  
为使电路分析更加直观生动,可以将Matlab软件包引入到分析过程中.以具体的直流稳态电路、交流稳态电路和一阶暂态电路为例,详述了如何分别应用Matlab语言编程的方法和直接利用可视化仿真环境Simulink/PSB设计电路模型图的方法进行建模、计算和仿真分析.通过实例说明,Matlab软件包方便、简单、调节容易、可视性好,可成功地应用于电路的仿真与分析中,在教学和研究等领域具有广泛的应用前景和一定的推广价值.  相似文献   
40.
为了更有效的进行高压静电除尘,设计了一种新型除尘控制器,该系统以PLC为控制核心,以触摸屏为人机界面,实现了控制器与上位机之间的联机交互,兼顾了其他静电除尘器除尘效率高与易于操作维护的特点。  相似文献   
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