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991.
In this paper we present the results of AC loss measurements on silver clad monocore tapes of Tl-1223 prepared by the powder-in-tube method. Losses arising from an external AC magnetic field are compared with those generated by AC transport currents (self-field losses). Critical current densities are derived from magnetic loss data and compared with those measured by the four point transport method. It was found that mechanically induced stresses (introduced by bending) only have a significant effect on the transport losses, via the critical current degradation. Such changes are not seen in measured magnetic losses, which are independent of mechanical stress, and remain unchanged, at least in the stress range used in our experiment.  相似文献   
992.
周平  孙文婷  任志平 《工业工程》2011,14(2):109-111
针对营业厅固网业务服务流程繁琐、服务不及时、客户长时间排队等待的现状,基于工业工程(IE)理论,重新定义IE理论图表技术符号,应用“5W1H”提问技术分析现状,确定需要优化的项目;应用“ECRS”4大原则优化固网业务流程。以某市营业厅固网业务流程为例,优化后客户平均移动距离由69 m缩短至34 m、高峰期平均停留时间由58 min缩短至29 min,说明使用该方法优化固网业务流程效果明显。这对于提高客户满意度、提升服务质量和效率以及企业竞争实力具有指导作用。  相似文献   
993.
994.
As carbon-based nanomaterials, water-soluble C60 derivatives have potential applications in various fields of biomedicine. In this study, a water-soluble fullerene C60 derivative bearing alanine residues (Ala-C60) was synthesized. The effects of Ala-C60 on neural stem cells (NSCs) as seed cells were explored. Ala-C60 can promote the proliferation of NSCs, induce NSCs to differentiate into neurons, and inhibit the migration of NSCs. Most importantly, the Ala-C60 can significantly increase the cell viability of NSCs treated with hydrogen peroxide (H2O2). The glutathioneperoxidase (GSH-Px) and superoxide dismutase (SOD) activities and glutathione (GSH) content increased significantly in NSCs treated even by 20 μM Ala-C60. These findings strongly indicate that Ala-C60 has high potential to be applied as a scaffold with NSCs for regeneration in nerve tissue engineering for diseases related to the nervous system.  相似文献   
995.
Smoking is a risk factor for a variety of deleterious conditions, such as cancer, respiratory disease and cardiovascular disease. Thrombosis is an important and common aspect of several cardiovascular disease states, whose risk is known to be increased by both first- and secondhand smoke. More recently, the residual cigarette smoke that persists after someone has smoked (referred to as thirdhand smoke or THS) has been gaining more attention, since it has been shown that it also negatively affects health. Indeed, we have previously shown that 6-month exposure to THS increases the risk of thrombogenesis. However, neither the time-dependence of THS-induced thrombus formation, nor its sex dependence have been investigated. Thus, in the present study, we investigated these issues in the context of a shorter exposure to THS, specifically 3 months, in male and female mice. We show that the platelets from 3-month THS-exposed mice exhibited enhanced activation by agonists. Moreover, we also show that mice of both sexes exposed to THS have decreased tail bleeding as well as decreased thrombus occlusion time. In terms of the role of sex, intersex disparities in thrombus development and hemostasis as well as in platelet aggregation were, interestingly, observed. Together, our findings show that exposing mice to THS for 3 months is sufficient to predispose them to thrombosis; which seems to be driven, at least in part, by an increased activity in platelets, and that it does not manifest equally in both sexes.  相似文献   
996.
The evolution of mining-induced stress field in longwall panel is closely related to the fracture field and the breaking characteristics of strata.Few laborator...  相似文献   
997.
Zyxin is an LIM-domain-containing protein that regulates the assembly of F-actin filaments in cell contacts. Additionally, as a result of mechanical stress, Zyxin can enter nuclei and regulate gene expression. Previously, we found that Zyxin could affect mRNA stability of the maternally derived stemness factors of Pou5f3 family in Xenopus laevis embryos through binding to Y-box factor1. In the present work, we demonstrate that Zyxin can also affect mRNA stability of the maternally derived retinoid receptor Rxrγ through the same mechanism. Moreover, we confirmed the functional link between Zyxin and Rxrγ-dependent gene expression. As a result, Zyxin appears to play an essential role in the regulation of the retinoic acid signal pathway during early embryonic development. Besides, our research indicates that the mechanism based on the mRNA destabilization by Zyxin may take part in the control of the expression of a fairly wide range of maternal genes.  相似文献   
998.
Shi  Shun  Wang  JiaYu  Wang  TianRan  Ren  Hui  Zhou  YuHao  Li  Gao  He  ChaoLiang  Chen  XueSi 《中国科学:技术科学(英文版)》2021,64(3):641-650
Science China Technological Sciences - Glycopolypeptides as analogs of glycoproteins or glycosaminoglycans represent attractive building blocks for the construction of biomimetic biomaterials....  相似文献   
999.
1000.
Cysteine oxidation states of extracellular proteins participate in functional regulation and in disease pathophysiology. In the most common inherited dementia, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), mutations in NOTCH3 that alter extracellular cysteine number have implicated NOTCH3 cysteine states as potential triggers of cerebral vascular smooth muscle cytopathology. In this report, we describe a novel property of the second EGF-like domain of NOTCH3: its capacity to alter the cysteine redox state of the NOTCH3 ectodomain. Synthetic peptides corresponding to this sequence (NOTCH3 N-terminal fragment 2, NTF2) readily reduce NOTCH3 N-terminal ectodomain polypeptides in a dose- and time-dependent fashion. Furthermore, NTF2 preferentially reduces regional domains of NOTCH3 with the highest intensity against EGF-like domains 12–15. This process requires cysteine residues of NTF2 and is also capable of targeting selected extracellular proteins that include TSP2 and CTSH. CADASIL mutations in NOTCH3 increase susceptibility to NTF2-facilitated reduction and to trans-reduction by NOTCH3 produced in cells. Moreover, NTF2 forms complexes with the NOTCH3 ectodomain, and cleaved NOTCH3 co-localizes with the NOTCH3 ectodomain in cerebral arteries of CADASIL patients. The potential for NTF2 to reduce vascular proteins and the enhanced preference for it to trans-reduce mutant NOTCH3 implicate a role for protein trans-reduction in cerebrovascular pathological states such as CADASIL.  相似文献   
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