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排序方式: 共有719条查询结果,搜索用时 218 毫秒
61.
A. Oral Salman 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(2):196-213
The millimeter wave radiation of a dielectric leaky-wave antenna (DLWA) coupled with a metallic diffraction grating with a
sinusoidal height profile is experimentally investigated. The interaction between dielectric and grating is contactless and
it is from the broad-face of the dielectric line. The measured field patterns are compared with the simulated HFSS patterns.
Antenna parameters such as polarization, HPBW, cross-polarization and side lobe levels are measured. The effects of the geometrical
parameters of the grating to the radiation are also investigated. Some results are compared with a DLWA which has another
diffraction grating profile shape (rectangular). The investigated antenna can be used as a frequency scanning antenna in mm-wave
radars because it has low cross and side lobe levels and narrow beam width. 相似文献
62.
Salman R. Salman 《Polymer-Plastics Technology and Engineering》2013,52(1-2):115-122
Photooxidative aging of high-impact polystyrene sheets at 25°C was followed for different intervals of 25, 40, 50, 75, and 80 h. Five different types of samples were used, viz. virgin, and recycled once, twice, three, and four times. The optical properties of exposed samples exhibited changes as a result of discoloration. The transmittance and reflection deceases whereas absorbance increases with increasing recycling of high-impact polystyrene. 相似文献
63.
Adnan Khan Bushra Shal Ashraf Ullah Khan Rahim Ullah Muhammad Waleed Baig Ihsan ul Haq Eun Kyoung Seo Salman Khan 《International journal of molecular sciences》2021,22(11)
Vincristine (VCR) is a widely used chemotherapy drug that induced peripheral painful neuropathy. Yet, it still lacks an ideal therapeutic strategy. The transient receptor potential (TRP) channels, purinergic receptor (P2Y), and mitogen-activated protein kinase (MAPK) signaling play a crucial role in the pathogenesis of neuropathic pain. Withametelin (WMT), a potential Phytosteroid isolated from datura innoxa, exhibits remarkable neuroprotective properties. The present investigation was designed to explore the effect of withametelin on VCR-induced neuropathic pain and its underlying molecular mechanism. Initially, the neuroprotective potential of WMT was confirmed against hydrogen peroxide (H2O2)-induced PC12 cells. To develop potential candidates for neuropathic pain treatment, a VCR-induced neuropathic pain model was established. Vincristine (75 μg/kg) was administered intraperitoneally (i.p.) for 10 consecutive days (day 1–10) for the induction of neuropathic pain. Gabapentin (GBP) (60 mg/kg, i.p.) and withametelin (0.1 and 1 mg/kg i.p.) treatments were given after the completion of VCR injection on the 11th day up to 21 days. The results revealed that WMT significantly reduced VCR-induced pain hypersensitivity, including mechanical allodynia, cold allodynia, and thermal hyperalgesia. It reversed the VCR-induced histopathological changes in the brain, spinal cord, and sciatic nerve. It inhibited VCR-induced changes in the biochemical composition of the myelin sheath of the sciatic nerve. It markedly downregulated the expression levels of TRPV1 (transient receptor potential vanilloid 1); TRPM8 (Transient receptor potential melastatin 8); and P2Y nociceptors and MAPKs signaling, including ERK (Extracellular Signal-Regulated Kinase), JNK (c-Jun N-terminal kinase), and p-38 in the spinal cord. It suppressed apoptosis by regulating Bax (Bcl2-associated X-protein), Bcl-2 (B-cell-lymphoma-2), and Caspase-3 expression. It considerably attenuated inflammatory cytokines, oxidative stress, and genotoxicity. This study suggests that WMT treatment suppressed vincristine-induced neuropathic pain by targeting the TRPV1/TRPM8/P2Y nociceptors and MAPK signaling. 相似文献
64.
King Eden B.; Dunleavy Dana G.; Dunleavy Eric M.; Jaffer Salman; Morgan Whitney Botsford; Elder Katie; Graebner Raluca 《Canadian Metallurgical Quarterly》2011,17(1):54
Although scholars agree that traditional forms of discrimination have generally been supplanted by subtler interpersonal manifestations of discrimination, it is yet unknown whether targets of these behaviors or the American judicial branch recognize such negative behaviors as violations of extant law. Extending research and theory, we propose that denigrating messages toward women and ethnic minorities (i.e., microaggressions) emerge in workplace interactions and are sometimes interpreted as discrimination. Specifically, this research explores the presence, severity, and frequency of microaggressions that appear in a random sample of race and gender discrimination cases in federal court dockets since the year 2000. The results suggest that microinsults, microinvalidations, and microassaults are reported in a variety of discrimination claims. However, only overt and intentional forms of microaggressions (microassaults) increased the likelihood that decisions favored plaintiffs. Thus, there may be a disconnect between forms of discrimination perceived by claimants and how those forms are evaluated by the legal system that protects victims of discrimination. This potential misalignment of science and practice is discussed, as are directions for future research. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
65.
Salman M. A. Salman 《国际水》2013,38(4):580-585
Abstract International rivers serve a number of purposes, the most obvious are the navigational and non-navigational uses. Less noticed is the fact that international rivers are also used to delimit boundaries between nations. The immediate question that would arise is: Where are such boundaries actually drawn across the river? Boundaries, however, are established by treaties and the answer to this question is often included in the interpretation of treaties delimiting such water boundaries, taking into account the special characteristics of the international river. Indeed, this has been the case regarding the boundaries across the Chobe river between Botswana and Namibia. Determining where such boundaries lie would result in deciding to whom a disputed Island, the Kasikili/Sedudu, belongs. In a praiseworthy step, the two countries agreed to take their dispute over the Island, after failure to resolve it through negotiations, to the International Court of Justice. This paper discusses the uses of international rivers as boundaries, and reviews the dispute between Botswana and Namibia, and the decision of the Court thereon. 相似文献
66.
The crystallization behaviour of lithia calcia silicate system containing MgO, SrO, and Al2O3 has been investigated using DTA, XRD and SEM. The coefficient of thermal expansion and Vicker's microhardness of the obtained products were also evaluated. The main crystalline phases formed after different heat-treatments were lithium metasilicate, wollastonite, diopside, β-spodumene ss, pseudo-wollastonite, Sr2SiO4, Sr2Mg(Si2O7) and μ-(Ca,Sr)SiO3. The wollastonite structure can accept considerable amount of strontium to form wollastonite strontium solid solution, while there is no solid solution of strontium in pseudo-wollastonite. 相似文献
67.
Leen Seok Kang Hyoun Seok Moon Nashwan Dawood Min Su Kang 《Automation in Construction》2010,19(8):1000-1015
Current virtual reality (VR) and augmented reality (AR) tools do not lend themselves well to the simulation of non-repetitive activities that could be involved in road construction and heavy civil engineering projects. Therefore it is argued in this paper that specialised functions are required to support the use of VR and AR tools to visually design and simulate such projects. The prime objective of this study is to develop visual design and simulation analysis functions to support optimum road design by extending the applicability of current virtual reality (VR) systems to the design phase of road construction projects. The VR simulation functions developed in this research enable visual inspection of road alignment and earthwork status, simulation of alternative routes, and selection of optimum design route. This study implements a methodology for configuring VR simulation functions and develops a VR system for optimising the road design data. The research results include an improved road design process as a result of the application of the VR functions developed. 相似文献
68.
Salman M.A. Salman 《国际水》2013,38(3):415-418
Abstract Of the voluminous resolutions issued by United Nations General Assembly, the Millennium Declaration, adopted in 2000, is one of the most significant. It specifies eight development goals and sets the year 2015 as the target date for achieving such goals. Although water is not explicitly mentioned as one of those eight principal goals, it is specified as a subset under one of those goals. Three years later, the United Nations General Assembly paid special attention to water by issuing a separate resolution declaring the period 2005 to 2015 as the “International Decade for Action, Water for Life.” This article reviews and discusses the Resolution and analyzes its added value. 相似文献
69.
70.
BH Güven? T Salman B Tokar E Sürmen T AltuG A Celik 《Canadian Metallurgical Quarterly》1997,12(5-6):367-369
Fetal tissue transplantation has gathered considerable interest among researchers dealing with organ transplantation. A large number of studies concerning fetal intestinal transplantation have been published in the past 2 decades, almost all of them aiming to determine the feasibility of a properly functioning fetal transplant in continuity with the host's own enteral system. This study was designed to determine the absorptive capacity of the neogut in vivo, without anastomosing the transplant to the host's intestine, and to evaluate its use as an accessory enteral segment. Intestinal segments taken from Wistar albino fetuses were transplanted subcutaneously into the abdominal wall of 20 Sprague-Dawley rats. Immunosuppression was maintained by daily cyclosporin A (Cy A) 10 mg/kg injections s.c. and evaluated by determination of serum Cy A level and T-helper/T-suppressor cell ratio. The neogut was converted into a Thiry-Vella loop 2 weeks after transplantation. A test solution composed of 20% glucose and Trophamine was perfused via the stomas; glucose and amino acid absorption gradients were calculated. The gamma-glutamyl transferase (GGT) activity and mitotic index of the neogut were determined. Results were compared to those obtained from the host. There was no significant difference (P > 0.05) in glucose absorption between the neogut and the host tissue. Amino acid absorption and specific GGT activity were significantly less (P < 0.01) in the neogut. There was no significant difference (P > 0.05) between neogut and host intestine in mitotic index. Our data support the idea of using a transplanted fetal intestinal segment as an accessory feeding route. 相似文献