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81.
This work is devoted to the numerical study of the interaction of an inclined plane turbulent jet with a moving horizontal isothermal hot wall. The inclination of the jet allows the control of the stagnation point location. The numerical predictions based on statistical modeling are achieved using second order Reynolds stress turbulence model coupled to the enhanced wall treatment. The jet Reynolds number (Re), surface‐to‐jet velocity ratio (Rsj); and optimal inclination angle of the jet (α) are varied. The calculations are in good agreement with the available data. The numerical results show that the heat transfer is greatly influenced by the jet Re and the velocity of the moving wall. The local Nusselt number (Nu) decreases with increasing Rsj (until Rsj = 1). However, the optimal inclination of the jet enhances heat transfer and modifies significantly the stagnation point location. Average Nu is correlated according with the problem parameters as . 相似文献
82.
Dr. Anibal Cuetos Dr. Fabian Steffen‐Munsberg Dr. Juan Mangas Sanchez Amina Frese Prof. Dr. Uwe T. Bornscheuer Prof. Dr. Matthias Höhne Prof. Dr. Gideon Grogan 《Chembiochem : a European journal of chemical biology》2016,17(24):2308-2311
Pyridoxal‐phosphate (PLP)‐dependent enzymes catalyse a remarkable diversity of chemical reactions in nature. A1RDF1 from Arthrobacter aurescens TC1 is a fold type I, PLP‐dependent enzyme in the class III transaminase (TA) subgroup. Despite sharing 28 % sequence identity with its closest structural homologues, including β‐alanine:pyruvate and γ‐aminobutyrate:α‐ketoglutarate TAs, A1RDF1 displayed no TA activity. Activity screening revealed that the enzyme possesses phospholyase (E.C. 4.2.3.2) activity towards O‐phosphoethanolamine (PEtN), an activity described previously for vertebrate enzymes such as human AGXT2L1, enzymes for which no structure has yet been reported. In order to shed light on the distinctive features of PLP‐dependent phospholyases, structures of A1RDF1 in complex with PLP (internal aldimine) and PLP ? PEtN (external aldimine) were determined, revealing the basis of substrate binding and the structural factors that distinguish the enzyme from class III homologues that display TA activity. 相似文献
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Ahmed F. El‐Koraie Yasmine S. Naga Amina M. Saaran Nahla G. Farahat Walaa A. Hazzah 《Hemodialysis international. International Symposium on Home Hemodialysis》2013,17(3):359-365
Long‐term endotoxin challenge may promote frequent complications in dialysis patients, namely malnutrition, chronic inflammation, and atherosclerosis, which are recognized as the so‐called MIA syndrome. Circulating soluble vascular cell adhesion molecule‐1 (sVCAM‐1) levels may be used to determine the stage of atherosclerosis. This study aimed to assess endotoxin level in hemodialysis (HD) patients and its role in inducing inflammation. The study was conducted on 50 HD patients, chosen from four dialysis centers in Alexandria. Serum blood samples were collected for the determination of albumin and C‐reactive protein (CRP), and whole blood samples were used for the measurement of hemoglobin level. A heparinized whole blood sample was taken postdialysis for endotoxin assay by limulus amebocyte lysate test, and in addition to sVCAM‐1 was estimated using enzyme‐linked immunosorbent assay. The mean endotoxin level was 76.30 pg/mL;80% exhibited values higher than 60 pg/mL. Half the studied patients had CRP values that exceeded the upper limit of the laboratory reference range (<6.0 mg/L). A statistically significant correlation was found between endotoxin and CRP levels (r = 0.47, P = 0.001). The mean pre‐HD level of VCAM was 1851.00 ng/mL, while the mean post‐HD level was 2829.00 ng/mL with statistically significant correlation (r = 0.354, P = 0.012) and it also correlated significantly with endotoxin as well as CRP levels. Endotoxemia may play an important role in the aggravation of endothelial dysfunction in HD patients as indicated by the post‐HD rise in sVCAM‐1. 相似文献
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Mariarosaria De Falco Alessandra Porritiello Federica Rota Viviana Scognamiglio Amina Antonacci Giovanni del Monaco Mariarita De Felice 《International journal of molecular sciences》2022,23(5)
Generation of the 3′ overhang is a critical step during homologous recombination (HR) and replication fork rescue processes. This event is usually performed by a series of DNA nucleases and/or helicases. The nuclease NurA and the ATPase HerA, together with the highly conserved MRE11/RAD50 proteins, play an important role in generating 3′ single-stranded DNA during archaeal HR. Little is known, however, about HerA-NurA function and activation of this fundamental and complicated DNA repair process. Herein, we analyze the functional relationship among NurA, HerA and the single-strand binding protein SSB from Saccharolubus solfataricus. We demonstrate that SSB clearly inhibits NurA endonuclease activity and its exonuclease activities also when in combination with HerA. Moreover, we show that SSB binding to DNA is greatly stimulated by the presence of either NurA or NurA/HerA. In addition, if on the one hand NurA binding is not influenced, on the other hand, HerA binding is reduced when SSB is present in the reaction. In accordance with what has been observed, we have shown that HerA helicase activity is not stimulated by SSB. These data suggest that, in archaea, the DNA end resection process is governed by the strictly combined action of NurA, HerA and SSB. 相似文献
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Eyewitness research has identified sequential lineup testing as a way of reducing false lineup choices while maintaining accurate identifications. The authors examined the usefulness of this procedure for reducing false choices in older adults. Young and senior witnesses viewed a crime video and were later presented with target present or absent lineups in a simultaneous or sequential format. In addition, some participants received prelineup questions about their memory for a perpetrator's face and about their confidence in their ability to identify the culprit or to correctly reject the lineup. The sequential lineup reduced false choosing rates among young and older adults in target-absent conditions. In target-present conditions, sequential testing significantly reduced the correct identification rate in both age groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Amina Alrustamani Branimir Vojcic Andrej Stefanov 《Journal of Signal Processing Systems》2002,30(1-3):179-195
In this paper, we introduce a new greedy algorithm developed for communication systems characterized with multiple simultaneous data transmission. Specifically, we consider code-division multiple-access (CDMA) systems and systems employing space-time coding (STC). The optimum detection in such systems has an exponential complexity and cannot be used in practical systems. We show that performance close to the optimum performance yet with significantly lower complexity can be achieved by the proposed algorithm. Also, we show that its performance is significantly better than that of most of the existing sub-optimum schemes for a wide range of operating conditions. 相似文献