It is shown that use of the equation of motion of the Universe scale factor allows calculation of the contribution of the vacuum influctuations to the acceleration of the Universe expansion. Renormalization of the equ...
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It is shown that use of the equation of motion of the Universe scale factor allows calculation of the contribution of the vacuum influctuations to the acceleration of the Universe expansion. Renormalization of the equation is needed only in the case of massive particles. Under a known number of the different kinds of fundamental fields, this provides the determination of momentum of the ultraviolet cut-off from the observed value of acceleration.
Introduction and Aim: Myogenic response is an autoregulatory arterial constriction to elevated blood pressure – a reflex essential for proper blood flow distribution. Historically, it’s mechanistic basis is explaine...
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Introduction and Aim: Myogenic response is an autoregulatory arterial constriction to elevated blood pressure – a reflex essential for proper blood flow distribution. Historically, it’s mechanistic basis is explained as arterial depolarization opening voltage-gated Ca2+ channels (VGCC), the primary subtype being L-type (CaV1.2). While unarguably important, additional regulatory mechanisms may exist including one where T-type (CaV3.1) Ca2+ channels alone or in interaction with CaV1.2 play a facilitatory role in myogenic tone development. Methods: A detailed electrical analysis was completed using patch-clamp electrophysiology (whole-cell & cell-attached) on rodent cerebral arterial smooth muscle cells. Intracellular [Ca2+] ([Ca2+]i) in resistant arteries was assessed using pressure myography and Fura-2AM. Results: Whole-cell patch-clamp revealed that pressure-like stimuli increased the CaV1.2, but not the CaV3.1 current. Single channel analysis tied the CaV1.2 activity rise to enhanced 1) functional coupling and 2) subunit trafficking to caveolae. Pressure-induced functional coupling was observed in intact arteries as manifested by elevated [Ca2+]i (at 80 vs 20 mmHg) in the presence of 30 mM K+ to standardize membrane potential (-40mV). To test the role of CaV3.1 in pressure-regulation of CaV1.2, single channel analysis was repeated in arterial myocytes from CaV3.1−/− animals. Intriguingly, while pressure continued to foster CaV1.2 trafficking, it didn’t augment functional coupling. Likewise, we didn’t observe the elevated Ca2+ response in arteries (at 80 vs 20 mmHg) when membrane potential was standardized. There was, however, evidence of higher baseline CaV1.2 activity in both experimental sets. Conclusions: Our results indicate that pressure increases CaV1.2 activity by enhancing perimembrane trafficking and functional coupling. We propose that the latter is tied to CaV3.1 and the induction of Ca2+-induced inactivation, an effect that partly dissipates as an arter
Mesopelagic fishes were collected from depths of 400 to 900 m off Oregon (USA) in September 1983, October 1985 and June 1989. Species of mesopelagic fish without diel vertical migrations (non-migrators) are known to h...
Mesopelagic fishes were collected from depths of 400 to 900 m off Oregon (USA) in September 1983, October 1985 and June 1989. Species of mesopelagic fish without diel vertical migrations (non-migrators) are known to have high body- and muscle-water contents relative to epipelagic and vertically migrating mesopelagic species. This characteristic is reported to correlate with low food availability. Through histology, we show that four species of swimbladderless non-migrators (Bathylagus pacificus, B. milleri, Tactostoma macropus and Chauliodus macouni) have large deposits of gelatinous material which stain positively for acidic glycosaminoglycans (GAGs) and negatively for lipid and protein. GAGs are highly hygroscopic and are thus responsible in part for the high body-water content of these species. The material is located between myotomal (swimming) muscle cells, along the dorsal midline and surrounding the spine in all four species, and the two Bathylagus species have an additional subcutaneous layer. The subcutaneous layer of B. pacificus has very high (96%) water, low protein (3%) and low ion contents and is positively buoyant, unlike myotomal muscle (89% water, 6.7% protein, negatively buoyant). In contrast, four species of vertical migrators (***, Stenobrachius leucopsarus, Tarletonbeania crenularis and Diaphus theta) have no such deposits. The role of this gelatinous material as a possible buoyancy mechanism in an energy-poor habitat is discussed.
文档一体化理论在档案管理学中已经出现多年,并逐渐被认识与接受.但真正被运用到医院的管理上,确是近些年才开始,还有一段很长的距离要走.随着21世纪信息化的发展越来越快,各个部门开始越来越重视对文件档案信息的管理.本文正是从这个立足点出发,先阐述文档一体化的概念,其中具体分析了文档一体化出现的原因以及其重要性,并对比传统的文档管理中的文件处理和档案管理.然后本文将会介绍文档一体化的发展所需要的几个重要条件,强调文档一体化管理是提高档案管理质量和工作效率有效方法.最后,将会介绍文档一体化实用的软件,比如OA(office automation)和PDE(Public data editor or personal data editor).总的来说,本文阐述医学文档一体化的必然性,发展以及在医院的应用.
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