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71.
G Stuhler A Zobywalski F Grünebach P Brossart VL Reichardt H Barth S Stevanovic W Brugger L Kanz SF Schlossman 《Canadian Metallurgical Quarterly》1999,96(4):1532-1535
Help for the induction of cytolytic T lymphocytes is mediated by dendritic cells (DC) that are conditioned by CD40 signaling. We identified tumor necrosis factor family member CD27L/CD70, which is expressed by cytolytic T lymphocytes on interaction with DC to control CD154 (CD40L) up-regulation on CD45RA+ helper T cells for subsequent DC stimulation. The results show that the initiation of a cytolytic immune response is determined by regulatory circuits, requiring simultaneous activation and differentiation of all cells involved in T lymphocyte-DC cluster formation. 相似文献
72.
How do the professional lives of psychologists influence their personal and family lives? Data from 485 psychologists who responded to a survey on professional and family life were analyzed to examine work-to-family spillover, life satisfaction, and family support. Respondents reported a significantly higher incidence of positive spillover, termed family enhancers, than negative spillover, termed family stressors. The low incidence of family stressors suggested that stresses associated with the professional work of psychology do not routinely spill over into professionals' family lives. Both positive and negative spillover, however, played significant roles in mediating the relationship between work and family domains. On the positive side, a sense of personal accomplishment at work was associated with increased family enhancers, which appeared to lead to greater family support and life satisfaction. On the negative side, emotional exhaustion at work was associated with more family stressors, which appeared to lead to less family support and life satisfaction. The implications of these findings for training and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
74.
ABSTRACT In this paper we are promoting the properties related to wood anatomy and chemical composition as the factor of influence to limit of hygroscopicity of wood (LH). The wood samples of the most important domestic Hood species: oak Ouercus robur, beech Fogus sylvatica, fir Abies alba and spruce Picea abies were selected for this investigation. For determining LH in our investigations we have applied the method of compression strength parallel to grain. The results of experimental measurements were statistically analyzed and the empirical equation for LH dependance upon the significant (influential) factors: temperature. cellullse content and wood density in oven dry state is defined. 相似文献
75.
Reliability of masonry walls subjected to in‐plane loading: A slip failure along head joints / Zuverlässigkeit von Mauerwerkswänden bei Belastung in der Ebene: Versagen entlang der Stoßfugenflucht 下载免费PDF全文
Masonry structures are a sustainable, economical and traditionally widely used type of construction. However, current masonry design codes are rather conservative, so there is a growing need for revision i.e. calibration of safety factors to improve the allocation of material resources. In this paper, we investigate the probability of occurrence of slip failure along head joints (perpends) in masonry subjected to in‐plane loading. An appropriate limit state function is established and the masonry material properties and loads are defined as random variables in order to simulate likelihood of occurrence of a slip failure regime along the head joints. Furthermore, an example of masonry wall with probabilistic analysis outcomes using Monte Carlo simulation is presented and recommendations for further work are provided. 相似文献
76.
Miroslav Ćirić Aleksandar Stamenković Jelena Ignjatović Tatjana Petković 《Journal of Computer and System Sciences》2010,76(7):609-633
We show that the state reduction problem for fuzzy automata is related to the problem of finding a solution to a particular system of fuzzy relation equations in the set of all fuzzy equivalences on its set of states. This system may consist of infinitely many equations, and finding its non-trivial solutions may be a very difficult task. For that reason we aim our attention to some instances of this system which consist of finitely many equations and are easier to solve. First, we study right invariant fuzzy equivalences, and their duals, the left invariant ones. We prove that each fuzzy automaton possesses the greatest right (resp. left) invariant fuzzy equivalence, which provides the best reduction by means of fuzzy equivalences of this type, and we give an effective procedure for computing this fuzzy equivalence, which works if the underlying structure of truth values is a locally finite residuated lattice. Moreover, we show that even better reductions can be achieved alternating reductions by means of right and left invariant fuzzy equivalences. We also study strongly right and left invariant fuzzy equivalences, which give worse reductions than right and left invariant ones, but whose computing is much easier. We give an effective procedure for computing the greatest strongly right (resp. left) invariant fuzzy equivalence, which is applicable to fuzzy automata over an arbitrary complete residuated lattice. 相似文献
77.
Nakrst J Bistan M Tisler T Zagorc-Koncan J Derco J Gotvajn AZ 《Water science and technology》2011,63(10):2131-2137
This study compares efficiency of Fenton's oxidation and ozonation of 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) as two possible processes for removal of estrogens from aqueous solutions. The effectiveness of Fenton's oxidative removal was studied at different ratios of reagents Fe2+:H2O2 (1:0.5; 1:10; 1:20; 1:33), where with some molar ratios up to 100% removal of E2 and EE2 was achieved in the first few minutes of reaction. The best molar ratio for E2 (17beta-estradiol) removal was 1:33, while in the case of EE2 the most efficient one was 1:20 ratio. Ozonation was much faster, because complete removal of estrogens was achieved in 30 seconds (pH approximately eaqual 6), but the time of ozonation was extended up to 60 minutes trying to decompose formed by-products, expressing estrogenic activity, detected by YES (Yeast Estrogen Screening) assay. The obtained results showed that the removal efficiency of estrogens from waters should be assessed by a combination of chemical analyses and bioassay. 相似文献
78.
Ioannis Z. Emiris Tatjana Kalinka Christos Konaxis Thang Luu Ba 《Computer aided design》2013,45(2):252-261
We revisit implicitization by interpolation in order to examine its properties in the context of sparse elimination theory. Based on the computation of a superset of the implicit support, implicitization is reduced to computing the nullspace of a numeric matrix. The approach is applicable to polynomial and rational parameterizations of curves and (hyper)surfaces of any dimension, including the case of parameterizations with base points. Our support prediction is based on sparse (or toric) resultant theory, in order to exploit the sparsity of the input and the output. Our method may yield a multiple of the implicit equation: we characterize and quantify this situation by relating the nullspace dimension to the predicted support and its geometry. In this case, we obtain more than one multiple of the implicit equation; the latter can be obtained via multivariate polynomial GCD (or factoring). All of the above techniques extend to the case of approximate computation, thus yielding a method of sparse approximate implicitization, which is important in tackling larger problems. We discuss our publicly available Maple implementation through several examples, including the benchmark of a bicubic surface. For a novel application, we focus on computing the discriminant of a multivariate polynomial, which characterizes the existence of multiple roots and generalizes the resultant of a polynomial system. This yields an efficient, output-sensitive algorithm for computing the discriminant polynomial. 相似文献
79.
Peng Ren Tatjana Aleksi? David Emms Richard C. Wilson Edwin R. Hancock 《Quantum Information Processing》2011,10(3):405-417
In this paper we explore an interesting relationship between discrete-time quantum walks and the Ihara zeta function of a
graph. The paper commences by reviewing the related literature on the discrete-time quantum walks and the Ihara zeta function.
Mathematical definitions of the two concepts are then provided, followed by analyzing the relationship between them. Based
on this analysis we are able to account for why the Ihara zeta function can not distinguish cospectral regular graphs. This
analysis suggests a means by which to develop zeta functions that have potential in distinguishing such structures. 相似文献
80.
Radovi? T Gruji? S Dujakovi? N Radi?i? M Vasiljevi? T Petkovi? A Boreli-Zdravkovi? D Dimki? M Lau?evi? M 《Water science and technology》2012,66(3):659-665
Pharmaceuticals are emerging contaminants with damaging effects to the environment and human health. Their presence in surface and especially groundwaters is regarded as detrimental, as they can ultimately reach drinking water. The aim of this work was to monitor pharmaceutical contamination of the Danube River and its tributaries in Serbia, and to assess the potential of their passing through all natural filtrations and reaching the groundwater. A total of 70 surface and groundwater samples was collected at 38 sampling sites at the Danube in Serbia. They were taken in five sampling campaigns performed in summer and autumn of 2009 and winter, spring and autumn of 2010. Samples were analyzed using a previously developed method which includes solid-phase extraction followed by liquid chromatography-tandem mass spectrometry. 相似文献