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61.
The operation of a cutting wedge is studied in order to improve coating application on tools. A method of investigating the coating characteristics in plant conditions is outlined. The mechanisms of coating failure in cutting are established. The blunting of tools in the course of operation is analyzed. Coating application is optimized.  相似文献   
62.
The isothermal fuel cell model, given in an earlier publication, will be generalized to describe the behaviour of non-isothermal fuel cells of co-flow type. To this end the temperalure distribution inside a fuel cell in steady state is investigated analytically. A simplified relation between the local temperature and the fuel utilization is derived and its practical significance elucidated. Furthermore, it is shown that the solution of the non-isothermal model is accurately approximated by analytical expressions obtained from a so-called quasi-isothermal approach. This new approach yields a similar expression for the cell voltage as derived from the isothermal model. The quasi-isothermal approach is also used to make a clear comparison between the isothermal and the non-isothermal fuel cell model.  相似文献   
63.
Traditional behavioral tests, such as the open field test, measure an animal's responsiveness to a novel environment. However, it is generally difficult to assess whether the behavioral response obtained from these tests relates to the expression level of motor activity and/or to avoidance of anxiogenic areas. Here, an automated home cage environment for mice was designed to obtain independent measures of motor activity levels and of sheltered feeding preference during three consecutive days. Chronic treatment with the anxiolytic drug chlordiazepoxide (5 and 10 mg/kg/day) in C57BL/6J mice reduced sheltered feeding preference without altering motor activity levels. Furthermore, two distinct chromosome substitution strains, derived from C57BL/6J (host strain) and A/J (donor strain) inbred strains, expressed either increased sheltering preference in females (chromosome 15) or reduced motor activity levels in females and males (chromosome 1) when compared to C57BL/6J. Longitudinal behavioral monitoring revealed that these phenotypic differences maintained after adaptation to the home cage. Thus, by using new automated behavioral phenotyping approaches, behavior can be dissociated into distinct behavioral domains (e.g., anxiety-related and motor activity domains) with different underlying genetic origin and pharmacological responsiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
65.
DNA cleavage stimulated by different topoisomerase II inhibitors shows in vitro a characteristic sequence specificity. Since chromatin structure and genome organization are expected to influence drug-enzyme interactions and repair of drug-induced DNA lesions, we investigated topoisomerase II DNA cleavage sites stimulated by teniposide (VM-26), 4-demethoxy-3'-deamino-3'-hydroxy-4'-epi-doxorubicin (dh-EPI, a doxorubicin derivative), 4'-(9-acridinylamino)-methanesulfon-m-anisidide, and amonafide in the histone gene locus and satellite III DNA of Drosophila cells with Southern blottings and genomic sequencing by primer extension. VM-26 stimulated cleavage in the satellite III DNA, whereas the other studied drugs did not. All four drugs stimulated cleavage in the histone gene cluster, but they yielded drug-specific cleavage intensity patterns. Cleavage sites by dh-EPI and VM-26 were sequenced in the histone H2A gene promoter and were shown to be distinct. DNA cleavage analysis in cloned DNA fragments with Drosophila topoisomerase II showed that drugs stimulated the same sites in vivo and in vitro. Strand cuts were in vivo staggered by 4 bases, and base sequences at major dh-EPI and VM-26 sites completely agreed with known in vitro drug sequence specificities. Moreover, DNA cleavage reverted faster in the satellite III than in the histone repeats. While stimulating similar levels of DNA breakage in bulk genomic DNA, dh-EPI and VM-26 markedly differed for cleavage extent and reversibility in specific chromatin loci. The results demonstrate a high heterogeneity in the localization, extent, and reversibility of drug-stimulated DNA cleavage in the chromatin of living cells.  相似文献   
66.
Regulatory T cells (Tregs) are major drivers behind immunosuppressive mechanisms and present a major hurdle for cancer therapy. Tregs are characterized by a high expression of CD25, which is a potentially valuable target for Treg depletion to alleviate immune suppression. The preclinical anti-CD25 (αCD25) antibody, clone PC-61, has met with modest anti-tumor activity due to its capacity to clear Tregs from the circulation and lymph nodes, but not those that reside in the tumor. The optimization of the Fc domain of this antibody clone has been shown to enhance the intratumoral Treg depletion capacity. Here, we generated a stable cell line that produced optimized recombinant Treg-depleting antibodies. A genome engineering strategy in which CRISPR-Cas9 was combined with homology-directed repair (CRISPR-HDR) was utilized to optimize the Fc domain of the hybridoma PC-61 for effector functions by switching it from its original rat IgG1 to a mouse IgG2a isotype. In a syngeneic tumor mouse model, the resulting αCD25-m2a (mouse IgG2a isotype) antibody mediated the effective depletion of tumor-resident Tregs, leading to a high effector T cell (Teff) to Treg ratio. Moreover, a combination of αCD25-m2a and an αPD-L1 treatment augmented tumor eradication in mice, demonstrating the potential for αCD25 as a cancer immunotherapy.  相似文献   
67.
Reinforced 3 male Carneaux pigeons for depressing a foot treadle according to multiple VI/VI schedules. After rates of responding stabilized, the schedule in 1 component was changed to extinction. This manipulation resulted in either no change or a decrease in rate of responding in the unchanged component. The Ss were then reinforced for key pecking under the same procedure. When key pecking was the operant, the experimental manipulation resulted in behavioral contrast. Results are discussed in terms of Pavlovian * Instrumental interactions. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
We prepared micron and submicron polymethylmethacrylate (PMMA) layers by the spin-coating method. We investigated the possibility to orientate polymer dipoles in electric field in the glass transition area (T g) and the fluid temperature of PMMA with the aim to increase its refractive index (n) after the layer is cooled below T g. We have studied the effect of electric field (up to 12 kV cm−1) on change of surface morphology of the layer, dependence of n and contact angle (surface wettability) on the field and dependence of layers orientation on orientation of electric field. The surface morphology was examined using atomic force microscopy (AFM), contact angles were measured by goniometer, film thickness was measured by profilometer, refractive index of films was determined using refractometer. The change of refractive index as dependent on the PMMA layer orientation in electric field depends on temperature and electric field. The highest change in n was found for electric field 11 kV cm−1. The change in contact angle (wettability) on surface of an orientated PMMA layer confirms the dipoles orientation in electric field unambiguously. The orientation of layers causes a “slight” change in their morphology and a “slight” increase of surface roughness only for one direction of field effect. Change in colour for oriented layers does not depend on orientation of electric field.  相似文献   
69.
像吞吃羚羊的蛇一样,隔音屏包含着Hessing 展示厅。隔音屏有1.5 km长,13m高,使A2高速公路旁的新公寓楼不受噪音干扰。A2高速公路自重建后有14条车道。在隔音屏中间融合的是国有的 Hessing公司的汽车展示厅,展示着罗尔斯·罗易  相似文献   
70.
咸水亭     
状态:完成;地点:Necltje、Jans Zeeland;建筑面积:656 m2;预算:1.2百万欧元;日期:1997。咸水亭最开始是从一个三维计算机模型的设计过程中演变而来的。我们揉,舒展,弯曲, 重新测量,定型和擦亮。形式的描述被制定在  相似文献   
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