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71.
The H + D2 reactive system was studied in the energy range 0.84 < Etr < 2.70 eV employing the ordinary Quasi-Classical Trajectory Approach (QCTA), the Classical and the Quantum Reactive Infinite Order Sudden Approximations (CRIOSA and QRIOSA), and the Angle-Oriented Transition State Theory (AOTST). From a detailed analysis of the various integral cross-sections and opacity functions, it was concluded that pronounced quantum effects ( > 10%) are expected in the high-energy region (≤ 2 eV). 相似文献
72.
Ron Commander 《化工中间体》2008,4(11):77-79
丁基橡胶是一种具有多种独特属性的神奇材料。这是我们所有的产品线中为数不多可食用产品。我们是全球口香糖行业唯一的原料供应商。然而,并不是出于这个原因,我的业务部才决定在新加坡兴建新的丁基橡胶生产厂——朗盛历史上金额最大的投资项目。下面,我将向大家解释朗盛为什么要将新工厂设在新加坡,以及我们是如何应对轮胎行业(为公车、卡车和汽车提供轮胎)市场变化。同时,这些变化为朗盛带来了绝佳的发展机会。 相似文献
73.
Keith Rozenburg Ivar E. Reimanis Hans-Joachim Kleebe Ron L. Cook 《Journal of the American Ceramic Society》2008,91(2):444-450
The sintering kinetics of a pure magnesium aluminate spinel, MgAl2 O4 , and that doped with LiF were determined through the use of the master sintering curve technique developed by Su and Johnson. 20 Powders with 0%, 0.5%, and 1.0% by mass LiF were densified in a vacuum hot press under a range of unaxial pressures. After the sintering mechanisms in each temperature and pressure regime were determined, an optimized vacuum hot-pressing schedule was formulated for spinel powders doped with 1.0% by mass of LiF. In addition to forming a transient liquid phase, the presence of LiF leads to the formation of oxygen vacancies that promote late-stage sintering in MgAl2 O4 . 相似文献
74.
Ola Gutziet Roee Iluz Hila Ben Asher Linoy Segal Dikla Ben Zvi Yuval Ginsberg Nizar Khatib Osnat Zmora Michael G. Ross Zeev Weiner Ron Beloosesky 《International journal of molecular sciences》2021,22(24)
Perinatal hypoxia is a major cause of infant brain damage, lifelong neurological disability, and infant mortality. N-Acetyl-Cysteine (NAC) is a powerful antioxidant that acts directly as a scavenger of free radicals. We hypothesized that maternal-antenatal and offspring-postnatal NAC can protect offspring brains from hypoxic brain damage.Sixty six newborn rats were randomized into four study groups. Group 1: Control (CON) received no hypoxic intervention. Group 2: Hypoxia (HYP)-received hypoxia protocol. Group 3: Hypoxia-NAC (HYP-NAC). received hypoxia protocol and treated with NAC following each hypoxia episode. Group 4: NAC Hypoxia (NAC-HYP) treated with NAC during pregnancy, pups subject to hypoxia protocol. Each group was evaluated for: neurological function (Righting reflex), serum proinflammatory IL-6 protein levels (ELISA), brain protein levels: NF-κB p65, neuronal nitric oxide synthase (nNOS), TNF-α, and IL-6 (Western blot) and neuronal apoptosis (histology evaluation with TUNEL stain). Hypoxia significantly increased pups brain protein levels compared to controls. NAC administration to dams or offspring demonstrated lower brain NF-κB p65, nNOS, TNF-α and IL-6 protein levels compared to hypoxia alone. Hypoxia significantly increased brain apoptosis as evidenced by higher grade of brain TUNEL reaction. NAC administration to dams or offspring significantly reduce this effect. Hypoxia induced acute sensorimotor dysfunction. NAC treatment to dams significantly attenuated hypoxia-induced acute sensorimotor dysfunction. Prophylactic NAC treatment of dams during pregnancy confers long-term protection to offspring with hypoxia associated brain injury, measured by several pathways of injury and correlated markers with pathology and behavior. This implies we may consider prophylactic NAC treatment for patients at risk for hypoxia during labor. 相似文献
75.
Umakanta Swain Gilgi Friedlander Urmila Sehrawat Avital Sarusi-Portuguez Ron Rotkopf Charlotte Ebert Tamar Paz-Elizur Rivka Dikstein Thomas Carell Nicholas E. Geacintov Zvi Livneh 《International journal of molecular sciences》2021,22(13)
TENT4A (PAPD7) is a non-canonical poly(A) polymerase, of which little is known. Here, we show that TENT4A regulates multiple biological pathways and focuses on its multilayer regulation of translesion DNA synthesis (TLS), in which error-prone DNA polymerases bypass unrepaired DNA lesions. We show that TENT4A regulates mRNA stability and/or translation of DNA polymerase η and RAD18 E3 ligase, which guides the polymerase to replication stalling sites and monoubiquitinates PCNA, thereby enabling recruitment of error-prone DNA polymerases to damaged DNA sites. Remarkably, in addition to the effect on RAD18 mRNA stability via controlling its poly(A) tail, TENT4A indirectly regulates RAD18 via the tumor suppressor CYLD and via the long non-coding antisense RNA PAXIP1-AS2, which had no known function. Knocking down the expression of TENT4A or CYLD, or overexpression of PAXIP1-AS2 led each to reduced amounts of the RAD18 protein and DNA polymerase η, leading to reduced TLS, highlighting PAXIP1-AS2 as a new TLS regulator. Bioinformatics analysis revealed that TLS error-prone DNA polymerase genes and their TENT4A-related regulators are frequently mutated in endometrial cancer genomes, suggesting that TLS is dysregulated in this cancer. 相似文献
76.
77.
During my career in Congress, we have achieved some success in expanding health insurance coverage and keeping services affordable, but the problem of 46 million uninsured and 25 million underinsured must be addressed. In February 2009, I introduced the Healthy Americans Act (S. 391/H.R. 1321; Wyden, 2009), a comprehensive bipartisan health care reform bill that covers all Americans without breaking the bank, by weaving together the Democratic idea that we need to give every single person in the country health care coverage and the Republican belief in a private-market approach. This bill would favorably affect providers in nonprofit institutions, public institutions, and school systems, by ending cost shifting from public program underpayments to the privately insured. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Krishnamoorthy A.V. Ron Ho Xuezhe Zheng Schwetman H. Jon Lexau Koka P. GuoLiang Li Shubin I. Cunningham J.E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2009,97(7):1337-1361
We present a computing microsystem that uniquely leverages the bandwidth, density, and latency advantages of silicon photonic interconnect to enable highly compact supercomputer-scale systems. We describe and justify single-node and multinode systems interconnected with wavelength-routed optical links, quantify their benefits vis-a-vis electrically connected systems, analyze the constituent optical component and system requirements, and provide an overview of the critical technologies needed to fulfill this system vision. This vision calls for more than a hundredfold reduction in energy to communicate an optical bit of information. We explore the power dissipation of a photonic link, suggest a roadmap to lower the energy-per-bit of silicon photonic interconnects, and identify the challenges that will be faced by device and circuit designers towards this goal. 相似文献
79.
随着半导体制造业的不断发展,对现场浓度测量的需求也不断增加。化学品浓度细微变化都会对晶圆缺陷等级造成不良影响,最为重要的是会对产量产生影响。另外,减少液态化学品废弃物流,使其对环境的影响最小化面临着不断增长的压力。 相似文献
80.
Prof. Dr. Hans Ulrich Buhl Dr. Bernd Heinrich Prof. Dr. Peter Loos Prof. Dr. Ulrich Frank Visiting Prof. Daniel L. Moody PhD Prof. Jeffrey Parsons PhD Prof. Dr. Michael Rosemann Prof. Dr. Elmar J. Sinz Prof. Ron Weber PhD Achim Kindler Dr. Prof. Dr. Claus Rautenstrauch Dipl.-Wirt.-Inf. Peter Fettke 《WIRTSCHAFTSINFORMATIK》2005,47(2):152-161