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11.
Immunity to tuberculosis (TB) required a Th1 pattern of cytokine release. In experimental models even a minor Th2 component abrogates immunity, and leads to an immunopathology that mimics the human disease. There to determine if Th2 cells are present in a peripheral blood, we analyzed the intracellular IL-4 using a flow cytometer. IL-4 producing cells were founded in CD4+ and CD4- Tells. Moreover, we studied about gamma delta (gamma delta) T cells in TB patients. V gamma 9-expressing gamma delta T cells were decreased in patients. However, the proliferative response to PPD by V gamma 9-expressing gamma delta T cells from some patients were higher levels compared with controls. The roles of gamma delta T cells of TB were not yet revealed completely.  相似文献   
12.
电子封装业界正遭受着前所未有的来自手机和其他移动通讯终端设备挑战。在这一领域里,IC封装的关键是尺寸微型化,缩减成本和市场时机。这一挑战的背后隐含着手机技术发展的两大趋势:系统模块化和日益增长的复杂性及功能。越来越多的功能正在被组合到手机上即PDA、MP3、照相机、互联网等等。功能的增加需要靠模块化来实现,而模块化又促进了更多功能的组合。同时,模块化使得移动通讯终端设备得以微型化、降低成本和缩短设计周期。业界越来越多地感受到整体射频模块和通讯模块解决方案的必要性。这些整体模块把手机设计师从电路设计的细节中解脱出来,从而能专著于高层的手机应用和系统的设计。为了满足上诉移动通讯产品的苛刻要求,大量的新兴电子封装技术和封装产品应运而生。最引人注目的例子在于对系统模块穴SiP雪和三维穴3D雪封装的重点资金和技术投入。这两项先进封装技术有着各自不同的特征和应用范围。总体介绍先进封装技术在移动通讯中的应用,重点讨论电子封装材料和工艺所面临的挑战和最新发展趋势。对移动通讯带来的新一轮集成化及其所产生的潜在供应链问题也做了适当的讨论。  相似文献   
13.
A micro-space cell culture system was recently developed in which cells such as hepatocytes can be cultured and formed into a multicellular three-dimensional (3D) architecture. In this study, we assessed the performance of HepG2 cells cultured in this micro-space cell culture system in a drug toxicity test, and evaluated the effects of micro-space culture on their hepatocyte-specific functions. The micro-space cell culture facilitated the formation of 3D HepG2 cell architecture. HepG2 cells cultured in a micro-space culture plate exhibited increased albumin secretion and enhanced mRNA expression levels of cytochrome P450 (CYP) enzyme compared to those cultured in a monolayer culture. When the cells were exposed to acetaminophen, a hepatotoxic drug, the damage to the HepG2 cells grown in micro-space culture was greater than the damage to the HepG2 cells grown in monolayer culture. In addition, human primary hepatocytes grown in micro-space culture also exhibited increased albumin secretion, enhanced CYP mRNA expression levels and increased sensitivity to acetaminophen compared to those grown in monolayer culture. These results suggest that this micro-space culture method enhances the hepatocyte-specific functions of hepatocytes, including drug-metabolizing enzyme activities, making hepatocytes grown in the micro-space culture system a useful tool for evaluating drug toxicity in vitro.  相似文献   
14.
This study demonstrates, for the first time, the principle of nuclear transmutation of minor actinide (MA) by the accelerator-driven system (ADS) through the injection of high-energy neutrons into the subcritical core at the Kyoto University Critical Assembly. The main objective of the experiments is to confirm fission reactions of neptunium-237 (237Np) and americium-241 (241Am), and capture reactions of 237Np. Subcritical irradiation of 237Np and 241Am foils is conducted in a hard spectrum core with the use of the back-to-back fission chamber that obtains simultaneously two signals from specially installed test (237Np or 241Am) and reference (uranium-235) foils. The first nuclear transmutation of 237Np and 241Am by ADS soundly implemented by combining the subcritical core and the 100 MeV proton accelerator, and the use of a lead-bismuth target, is conclusively demonstrated through the experimental results of fission and capture reaction events.  相似文献   
15.
Many circular motion measuring methods for NC machine tools have been proposed, however, the drawback common to many of these methods is the restriction on the radius size due to the short measuring range of the displacement transducers used. Moreover, most of these measurement tools are specialized, and can only perform circular test path measurements. A circularity test method using a laser displacement interferometer and a rotary encoder has been developed. The measuring method features a much longer range of motion than ordinal circular test methods such as the double ball bar (DBB) method and, therefore, the radius restriction on these measurements is greatly reduced. Moreover, this measuring system can also be used for the evaluation of positioning accuracy and other more complex test paths.

The proposed device consists primarily of a laser displacement interferometer and a rotary encoder. The holders for the interferometer head and the retroreflector are connected with a stainless steel rod. The retroreflector holder has a synthetic resin linear bearing allowing it to move relative to the interferometer head so that both optical components are always facing each other. The laser interferometer measures the change in distance between the interferometer head and the retroreflector, and the rotary encoder measures the rotation angle of the stainless steel rod.

In this paper, the background, measuring principle and apparatus structure are briefly described. The experimental setup is also presented. The apparatus was employed in several measuring experiments, including circularity tests for a vertical machining center. The results from these experiments support the validity of this measurement apparatus.  相似文献   

16.
A gripper comprising a jamming membrane was developed with the capability of grasping collapsible, soft, and fragile objects without applying heavy pressure. In disaster sites, it is necessary for robots to grab various types of objects, such as fragile objects. Deformable grippers that contain bags filled with powder cannot handle collapsible or soft objects without excessive pressure. Changing powder density relatively by changing inner volume is one approach to overcome this problem. By expanding the concept and simplifying the variable inner volume of the gripping mechanism, we developed a jamming membrane comprising the following three layers: outer layer and inner layer made of rubber and a powder layer in between the outer and inner rubber layer. This jamming membrane allows collapsible, soft, or fragile objects to be held securely without applying too much pressure. We designed and developed a prototype of the jamming membrane gripper. Our experiments confirmed the validity of the proposed jamming membrane mechanism.  相似文献   
17.
A simple instrument has been developed to carry out temperature dependent submillimeter/terahertz-wave spectroscopy using a polyvinylidene fluoride flexible hollow waveguide and an eggplant-shape launching lens.  相似文献   
18.
The death of photoreceptor cells is induced by continuous light exposure. However, it is unclear whether light damage was induced in retinal ganglion cells with photosensitivity by transduction of optogenetic genes. In this study, we evaluated the phototoxicities of continuous light exposure on retinal ganglion cells after transduction of the optogenetic gene mVChR1 using an adeno-associated virus vector. Rats were exposed to continuous light for a week, and visually evoked potentials (VEPs) were recorded. The intensities of continuous light (500, 1000, 3000, and 5000 lx) increased substantially after VEP recordings. After the final recording of VEPs, retinal ganglion cells (RGCs) were retrogradely labeled with a fluorescein tracer, FluoroGold, and the number of retinal ganglion cells was counted under a fluorescent microscope. There was no significant reduction in the amplitudes of VEPs and the number of RGCs after exposure to any light intensity. These results indicated that RGCs were photosensitive after the transduction of optogenetic genes and did not induce any phototoxicity by continuous light exposure.  相似文献   
19.
Herein, a nanoporous alumina was fabricated to use as a mold in transforming nanopillar structures onto a thin film polymer by thermal nanoimprint lithography (NIL). The size of the pores was successfully controlled by varying the applied voltages and etching time. These nanoporous structures were transferred to the Cyclo-olefin polymer (COP) film surface from the porous mold by a thermal nanoimprinting process. A plasmonic substrate was fabricated by sputtering a thin layer of gold onto this nanopillar polymer structure, and the refractive index response in a variety of media was evaluated. Finally, the biosensing capacity of this novel plasmonic substrate was verified by analysis of Human immunoglobulin and achieved a minimum detection limit of 1.0 ng/mL. With the advantages of mass production with consistent reproducibility stemming from the nanoimprint fabrication process, our gold-capped polymeric pillars are ready for the transition from academic interest into commercialization systems for practical use in diagnostic applications.  相似文献   
20.
Yao H  Kitaoka N  Sasaki A 《Nanoscale》2012,4(3):955-963
Versatile functionalization of metal clusters is a key step in understanding the reactivity of protective monolayers. We here demonstrate that reaction of the outermost amino groups on (S)-/(R)-penicillamine-protected gold clusters with ethyl isocyanate readily modifies the chiral surface structure through carbamoylation. Interestingly, the clusters are electrophoretically separated by the size of the surface ligand, not by the size of the gold core, which is revealed by UV-vis, IR, and energy dispersive X-ray (EDX) spectroscopy as well as SAXS measurements. The ligand size (or length) is extended through additional reactions of the carbamoylated amino groups with isocyanate, while the chemical similarity in ligand structures is realized by their IR spectral similarity. Optical and chiroptical responses of the separated cluster compounds are thus overall similar to each other, but a close inspection reveals that the ligand size has a small but distinct influence on the chiroptical response of the gold clusters.  相似文献   
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