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Experimental determination of mechanical properties and short-time creep of AISI 304 stainless steel at elevated temperatures 下载免费PDF全文
The high temperature properties of AISI 304 stainless steel were studied. Basic data about the employed experimental equipment, testing procedures, and specimen geometry were given. The experimental setup was used to obtain stress-strain diagrams from tensile tests at room temperature as well as several elevated temperatures. Furthermore, the specimens were subjected to short-time creep tests at various temperatures. Stress levels for creep testing were established as a percentage of yield stress. The results indicate that at lowered temperatures and lower stress levels, AISI 304 stainless steel can be used as a sufficiently creep resistant material. 相似文献
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Sam Kaitaniemi Heli Elovaara Kirsi Grön Heidi Kidron Janne Liukkonen Tiina Salminen Marko Salmi Sirpa Jalkanen Kati Elima 《Cellular and molecular life sciences : CMLS》2009,66(16):2743-2757
Semicarbazide-sensitive amine oxidases (SSAOs) catalyze oxidative deamination of primary amines, but the true physiological
function of these enzymes is still poorly understood. Here, we have studied the functional and structural characteristics
of a human cell-surface SSAO, AOC2, which is homologous to the better characterized family member, AOC3. The preferred in
vitro substrates of AOC2 were found to be 2-phenylethylamine, tryptamine and p-tyramine instead of methylamine and benzylamine, the favored substrates of AOC3. Molecular modeling suggested structural
differences between AOC2 and AOC3, which provide AOC2 with the capability to use the larger monoamines as substrates. Even
though AOC2 mRNA was expressed in many tissues, the only tissues with detectable AOC2-like enzyme activity were found in the
eye. Characterization of AOC2 will help in evaluating the contribution of this enzyme to the pathological processes attributed
to the SSAO activity and in designing specific inhibitors for the individual members of the SSAO family.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Sla?ana Laketi? Marko Rakin Milo? Mom?ilovi? Jovan Ciganovi? ?or?e Veljovi? Ivana Cvijovi?-Alagi? 《北京科技大学学报》2021,(2)
The effects of picosecond Nd:YAG laser irradiation on chemical and morphological surface characteristics of the commercially pure titanium and Ti–13 Nb–13 Zr alloy in air and argon atmospheres were studied under different laser output energy values. During the interaction of laser irradiation with the investigated materials, a part of the energy was absorbed on the target surface, influencing surface modifications.Laser beam interaction with the target surface resulted in various morphological alterations, resulting in crater formation and the presence of microcracks and hydrodynamic structures. Moreover, different chemical changes were induced on the target materials' surfaces, resulting in the titanium oxide formation in the irradiation-affected area and consequently increasing the irradiation energy absorption. Given the high energy absorption at the site of interaction, the dimensions of the surface damaged area increased. Consequently, surface roughness increased.The appearance of surface oxides also led to the increased material hardness in the surface-modified area. Observed chemical and morphological changes were pronounced after laser irradiation of the Ti–13 Nb–13 Zr alloy surface. 相似文献
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Chipping away at the chip bias: RNA degradation in microarray analysis 总被引:11,自引:0,他引:11
Auer H Lyianarachchi S Newsom D Klisovic MI Marcucci G Marcucci U Kornacker K 《Nature genetics》2003,35(4):292-293
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The chemotaxis signalling network in Escherichia coli that controls the locomotion of bacteria is a classic model system for signal transduction. This pathway modulates the behaviour of flagellar motors to propel bacteria towards sources of chemical attractants. Although this system relaxes to a steady state in response to environmental changes, the signalling events within the chemotaxis network are noisy and cause large temporal variations of the motor behaviour even in the absence of stimulus. That the same signalling network governs both behavioural variability and cellular response raises the question of whether these two traits are independent. Here, we experimentally establish a fluctuation-response relationship in the chemotaxis system of living bacteria. Using this relationship, we demonstrate the possibility of inferring the cellular response from the behavioural variability measured before stimulus. In monitoring the pre- and post-stimulus switching behaviour of individual bacterial motors, we found that variability scales linearly with the response time for different functioning states of the cell. This study highlights that the fundamental relationship between fluctuation and response is not constrained to physical systems at thermodynamic equilibrium but is extensible to living cells. Such a relationship not only implies that behavioural variability and cellular response can be coupled traits, but it also provides a general framework within which we can examine how the selection of a network design shapes this interdependence. 相似文献
17.
Barrett JH Iles MM Harland M Taylor JC Aitken JF Andresen PA Akslen LA Armstrong BK Avril MF Azizi E Bakker B Bergman W Bianchi-Scarrà G Bressac-de Paillerets B Calista D Cannon-Albright LA Corda E Cust AE Dębniak T Duffy D Dunning AM Easton DF Friedman E Galan P Ghiorzo P Giles GG Hansson J Hocevar M Höiom V Hopper JL Ingvar C Janssen B Jenkins MA Jönsson G Kefford RF Landi G Landi MT Lang J Lubiński J Mackie R Malvehy J Martin NG Molven A Montgomery GW van Nieuwpoort FA Novakovic S Olsson H 《Nature genetics》2011,43(11):1108-1113
We report a genome-wide association study for melanoma that was conducted by the GenoMEL Consortium. Our discovery phase included 2,981 individuals with melanoma and 1,982 study-specific control individuals of European ancestry, as well as an additional 6,426 control subjects from French or British populations, all of whom were genotyped for 317,000 or 610,000 single-nucleotide polymorphisms (SNPs). Our analysis replicated previously known melanoma susceptibility loci. Seven new regions with at least one SNP with P < 10(-5) and further local imputed or genotyped support were selected for replication using two other genome-wide studies (from Australia and Texas, USA). Additional replication came from case-control series from the UK and The Netherlands. Variants at three of the seven loci replicated at P < 10(-3): an SNP in ATM (rs1801516, overall P = 3.4 × 10(-9)), an SNP in MX2 (rs45430, P = 2.9 × 10(-9)) and an SNP adjacent to CASP8 (rs13016963, P = 8.6 × 10(-10)). A fourth locus near CCND1 remains of potential interest, showing suggestive but inconclusive evidence of replication (rs1485993, overall P = 4.6 × 10(-7) under a fixed-effects model and P = 1.2 × 10(-3) under a random-effects model). These newly associated variants showed no association with nevus or pigmentation phenotypes in a large British case-control series. 相似文献
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This paper concentrates on quantifying the behavioral aspects of systemic risk by using a novel approach based on entropy. More specifically, we study aggregate market expectations and the predictability of systemic risk before and during the financial crisis in 2008. Two underlying signals for estimating entropic risk measures are considered: (i) skewness premium of deepest out‐of‐the‐money options; and (ii) implied volatility ratio in regard to deepest out‐of‐the‐money options. The findings confirm the predictive and contemporaneous usefulness of our entropy setting in market risk management. The degree of predictability is closely linked to both the type of entropy and the nature of the underlying signal. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Pesu M Watford WT Wei L Xu L Fuss I Strober W Andersson J Shevach EM Quezado M Bouladoux N Roebroek A Belkaid Y Creemers J O'Shea JJ 《Nature》2008,455(7210):246-250
Furin is one of seven proprotein convertase family members that promote proteolytic maturation of proproteins. It is induced in activated T cells and is reported to process a variety of substrates including the anti-inflammatory cytokine transforming growth factor (TGF)-beta1 (refs 2-4), but the non-redundant functions of furin versus other proprotein convertases in T cells are unclear. Here we show that conditional deletion of furin in T cells allowed for normal T-cell development but impaired the function of regulatory and effector T cells, which produced less TGF-beta1. Furin-deficient T regulatory (Treg) cells were less protective in a T-cell transfer colitis model and failed to induce Foxp3 in normal T cells. Additionally, furin-deficient effector cells were inherently over-active and were resistant to suppressive activity of wild-type Treg cells. Thus, our results indicate that furin is indispensable in maintaining peripheral tolerance, which is due, at least in part, to its non-redundant, essential function in regulating TGF-beta1 production. Targeting furin has emerged as a strategy in malignant and infectious disease. Our results suggest that inhibiting furin might activate immune responses, but may result in a breakdown in peripheral tolerance. 相似文献
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