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51.
Adult hippocampal neurogenesis has been implicated in the pathophysiology of depression and in the therapeutic effects of antidepressant drugs. Current immunohistochemical methods that study neurogenesis are time consuming and labor intensive. Therefore, a significantly more rapid flow cytometric method was characterized to measure neurogenesis in the adult mouse brain. The sensitivity of mice to the effects of antidepressant treatments is dependent on genetic background. Thus, studies were conducted comparing the responsiveness of 2 inbred mouse strains, MRL/MpJ and C57BL/6J, to the acute and chronic effects of antidepressants on neurochemistry and behavior. Acutely, MRL/MpJ mice displayed more robust behavioral and neurochemical responses to pharmacologically distinct antidepressants than C57BL/6J mice. Chronic administration of the antidepressant drugs fluoxetine and desipramine produced robust elevations in hippocampal cell proliferation and brain-derived neurotrophic factor (BDNF) protein levels in MRL/MpJ mice. C57BL/6J mice treated similarly with antidepressant drugs were mainly unresponsive on these measures. Mice were tested in the novelty-induced hypophagia (NIH) paradigm to examine a behavioral response associated with chronic, but not acute, antidepressant treatment. Only MRL/MpJ mice were behaviorally responsive to chronic antidepressant administration in the NIH paradigm. The positive effects of chronic antidepressants on hippocampal cell proliferation and BDNF paralleled the ability of these drugs to produce changes in NIH behavior. These studies highlight the advantages of using flow cytometry to study hippocampal neurogenesis and identify the MRL/MpJ mouse as a strain with superior response to antidepressant drug treatments that may lead to a better understanding of the genetics behind antidepressant efficacy and sensitivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
In power system studies, congestion in transmission lines and utilization of flexible alternating current transmission system (FACTS) devices are closely associated. These devices are very important due to their role in power delivery system enhancement. It is to be noted that the generation companies can exercise their market power which depends on the line flows, line constraints, generators’ location and its share to the individual loads. This issue cannot be overlooked as it creates monopoliness which is against the deregulated market policy. The objective of this paper is to study the impact of market power when FACTS devices like thyristor controlled switching capacitor (TCSC) and thyristor controlled phase angle regulator (TCPAR) are used under steady state operation. The market power is determined using nodal must-run share (NMRS) index for the standard IEEE 14-bus system with and without the above FACTS devices and the results obtained are compared. All the above simulations are conducted in a MATLAB 7.9-R2009b environment. 相似文献
53.
Maria Krisandra L. Mendoza Bernard John V. Tongol Sangaraju Shanmugam Hasuck Kim 《International Journal of Hydrogen Energy》2018,43(43):19930-19938
Pulse electrodeposition of Pt and Sn using 10 mM H2PtCl6?6H2O in 0.10 M H2SO4 and 10 mM SnCl2?2H2O in 0.10 M HCl was conducted on a support matrix consisting of electropolymerized poly (3,4-ethylenedioxythiophene) (PEDOT) and electrochemically exfoliated graphene oxide (EGO). The Field Emission – Scanning Electron Microscopy (FE-SEM) studies of PtSn/PEDOT/EGO (i.e., PEDOT on EGO) showed a homogeneous globular composite, while PtSn/EGO/PEDOT (i.e., EGO on PEDOT) revealed a heterogeneous composite with wrinkled and globular surface morphologies. An Energy Dispersive X-ray (EDX) analysis (as a percentage of Pt and Sn) of PtSn/PEDOT/EGO is in agreement with the X-ray Photoelectron Spectroscopy (XPS) analysis, indicative of a homogeneous surface for the dispersion of metallic particles. However, the EDX and XPS analyses of PtSn/EGO/PEDOT showed variations in the amount of Pt and Sn, indicative of possible mixing of the EGO and PEDOT support matrices. Cyclic voltammetry (CV) and chronoamperometry using 1.0 M ethanol in 0.1 M H2SO4 demonstrated higher electrocatalytic activity (83.7 mA/cm2) and electrochemical stability (29.0% current retention) in PtSn/PEDOT/EGO than PtSn/EGO/PEDOT. 相似文献
54.
Shanmugam K Yoshinobu T Moon W Iwasaki H 《Journal of nanoscience and nanotechnology》2011,11(5):3808-3813
Oxide dots fabricated on silicon (111) by the Atomic Force Microscopy (AFM) anodic oxidation technique was used for the patterning of two different proteins namely, ferritin and fibronectin. Si surfaces were oxidized by the SC1 process and then modified with octadecyltrichlorosilane (OTS) for passivation. Oxide dots were fabricated by applying a bias voltage between the AFM probe and the silicon surface. Furthermore, surface functionalization of oxide dots was achieved through gamma-aminopropyltriethoxysilane (gamma-APTES) and glutaraldehye modification to establish a covalent bond between aldehydes and amino groups of protein molecules. Topographies after each modification steps were monitored by AFM. We were able to achieve positive patterning of ferritin molecules up to an average density of 6 x 10(9)/cm2 on gamma-APTES-covered dots, while 9 x 10(8)/cm2 of ferritin molecules remained on the OTS surface. In contrast to this observation, fibronectin molecules were patterned successfully only on oxide dots, and we did not observe any fibronectin molecules on the OTS surface. 相似文献
55.
衬衫织物是采用 6tex~ 3 0tex的纱线 ,根据最终要求织成的不同组织和结构的织物。高价值衬衫由 1 2tex较细的纱线制成 ,以上织物具有较高的经纬密度。这些纱线由环锭纺纱系统生产。尽管环锭纺纱线具有足够强度 ,但是它们的疵点水平仍然比自由端转杯纺纱线高。在转杯纺过程中生产出低水平的不太完善的纱线是可能的 ,但问题是转杯纺纱线常常是低强度 ,粗糙的手感和高的断头率 ,这在细纱转杯纺纱线的纺制过程中是要防止的。转杯纺要求纱线的横截面有 1 0 0根~ 1 2 0根纤维 ,这比环锭纺 5 0根纤维更令人满意。印度生产了单丝为 0 8… 相似文献
56.
Sundaresan Mohanraj Shanmugam Kodhaiyolii Mookan Rengasamy Velan Pugalenthi 《International Journal of Hydrogen Energy》2014
The effects of FeSO4 and synthesized iron oxide nanoparticles (0–250 mg/L) on fermentative hydrogen production from glucose and sucrose, using Enterobacter cloacae were investigated, to find out the enhancement of efficiency. The maximum hydrogen yields of 1.7 ± 0.017 mol H2/mol glucose and 5.19 ± 0.12 mol H2/mol sucrose were obtained with 25 mg/L of ferrous iron supplementation. In comparison, the maximum hydrogen yields of 2.07 ± 0.07 mol H2/mol glucose and 5.44 ± 0.27 mol H2/mol sucrose were achieved with 125 mg/L and 200 mg/L of iron oxide nanoparticles, respectively. These results indicate that the enhancement of hydrogen production on the supplementation of iron oxide nanoparticles was found to be considerably higher than that of ferrous iron supplementation. The activity of E. cloacae in a glucose and sucrose fed systems was increased by the addition of iron oxide nanoparticles, but the metabolic pathway was not changed. The results revealed that the glucose and sucrose fed systems conformed to the acetate/butyrate fermentation type. 相似文献
57.
Tensile and Impact Properties of Shielded Metal Arc Welded AISI 409M Ferritic Stainless Steel Joints
The present study is concerned with the effect of filler metals such as austenitic stainless steel, ferritic stainless steel and duplex stainless steel on tensile and impact properties of the ferritic stainless steel conforming to AISI 409M grade. Rolled plates of 4 mm thickness were used as the base material for preparing single pass butt welded joints. Tensile and impact properties, microhardness, microstructure and fracture surface morphology of the joints fabricated by austenitic stainless steel, ferritic stainless steel and duplex stainless steel filler metals were evaluated and the results were reported. From this investigation, it is found that the joints fabricated by duplex stainless steel filler metal showed higher tensile strength and hardness compared to the joints fabricated by austenitic and ferritic stainless steel filler metals. Joints fabricated by austenitic stainless steel filler metal exhibited higher ductility and impact toughness compared with the joints fabricated by ferritic stainless steel and duplex stainless steel filler metals. 相似文献
58.
V. Abhilash R. Balu S. Balaji S. Senthil Nathan S. Mohan 《Computational Materials Science》2004,30(3-4):523-529
In facing target sputtering (FTS) technique two targets facing each other are sputtered simultaneously and the particles are collected in the off axis position. When these two targets constitute two different materials having different sputtering yields, the deposited films show a gradation in composition along the axis parallel to the targets. The process parameters involved, increase the complexity of understanding the composition profile of the deposited films. Here an attempt has been made to simulate the transport behavior of the sputtered species, which leads to the theoretical realization of the variation in composition. The simulation has been performed for SmCo system using the Monte Carlo approach based on the empirical formula proposed by Sigmund and Thompson. The theoretical results have been compared with the experimental results obtained and are explained in detail. 相似文献
59.
60.
MP Shanmugam P De Potter L Gopal J Biswas MP Bhende 《Canadian Metallurgical Quarterly》1997,45(3):143-161
The management of intraocular tumours has come a long way since the days when enucleation was the only modality of treatment available to the ophthalmologist. Despite the fact that enucleation is still necessary in certain situations, the emphasis is currently on conservative management, thereby saving the eye and some amount of useful vision wherever possible. This review highlights the current trends in the management of adult intraocular tumours with emphasis on newer diagnostic modalities such as computed tomography, magnetic resonance imaging, and fine needle aspiration biopsy. Only those tumours that are most likely to be seen in clinical practice are included. 相似文献