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51.
Building on fairness heuristic theory, fairness theory, and trust development models, we argue that unfairly enacted procedures decrease followers' trust in the authority particularly when authorities have high power over their followers. Moreover, we expected trust to mediate procedural fairness effects on followers' attitudes (authorities' legitimacy and charisma attributed to authorities) and organizational citizenship behavior. Procedural fairness effects on these variables, as mediated by trust, should therefore also be stronger when authority power is high. The results of a single- and multisource field study and a laboratory experiment supported these predictions. These studies support the role of authority power as a theoretically and practically relevant moderator of procedural fairness effects and show that its effectiveness is explained through trust in authorities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Marius Eugen Ciurea Ada Maria Georgescu Stefana Oana Purcaru Stefan-Alexandru Artene Ghazaleh Hooshyar Emami Mihai Virgil Boldeanu Daniela Elise Tache Anica Dricu 《International journal of molecular sciences》2014,15(5):8169-8185
Almost all tumors are composed of a heterogeneous cell population, making them difficult to treat. A small cancer stem cell population with a low proliferation rate and a high tumorigenic potential is thought to be responsible for cancer development, metastasis and resistance to therapy. Stem cells were reported to be involved in both normal development and carcinogenesis, some molecular mechanisms being common in both processes. No less controversial, stem cells are considered to be important in treatment of malignant diseases both as targets and drug carriers. The efforts to understand the role of different signalling in cancer stem cells requires in depth knowledge about the mechanisms that control their self-renewal, differentiation and malignant potential. The aim of this paper is to discuss insights into cancer stem cells historical background and to provide a brief review of the new therapeutic strategies for targeting cancer stem cells. 相似文献
53.
54.
Sampling Archimedean copulas 总被引:2,自引:0,他引:2
Marius Hofert 《Computational statistics & data analysis》2008,52(12):5163-5174
The challenge of efficiently sampling exchangeable and nested Archimedean copulas is addressed. Specific focus is put on large dimensions, where methods involving generator derivatives are not applicable. Additionally, new conditions under which Archimedean copulas can be mixed to construct nested Archimedean copulas are presented. Moreover, for some Archimedean families, direct sampling algorithms are given. For other families, sampling algorithms based on numerical inversion of Laplace transforms are suggested. For this purpose, the Fixed Talbot, Gaver Stehfest, Gaver Wynn rho, and Laguerre series algorithm are compared in terms of precision and runtime. Examples are given, including both exchangeable and nested Archimedean copulas. 相似文献
55.
Barbara M. Rothen-Rutishauser Marius J. Messerli Hans van der Voort Maja Günthert Heidi Wunderli-Allenspach 《Journal of Computer-Assisted Microscopy》1998,10(3):103-111
The relative spatial distribution of proteins was investigated with immunofluorescent methods by confocal laser scanning microscopy and digital image restoration. For confocal data sets recorded with a voxel dimension of 50 × 50 × 150 nm noise and blur can be decreased and the resolution in the z-axis increased by applying the maximum likelihood estimation algorithm of the Huygens software. This approach was successfully applied to the study of tight and adherens junctions in relation to the actin cytoskeleton in Madin Darby Canine Kidney cells. Colocalization analysis was done for pairs of probes using a histogram-based method. F-actin, occludin, zonula occludens 1, and E-cadherin were included in the study. Double-labeled preparations were used. The combination of deconvolution with the colocalization of confocal data sets offers a powerful tool to investigate the spatial arrangement of proteins. 相似文献
56.
Silica‐containing polyimide films were prepared by sol‐gel technique using a poly(amic acid) and tetraethoxysilane. The poly(amic acid) was synthesized by solution polycondensation reaction of 4,4′‐oxydiphthalic anhydride with 2,6‐bis(3‐aminophenoxy)benzene and an aminosilane coupling agent, 3‐aminopropyltriethoxysilane. The properties of these films, such as water vapors sorption capacity, dynamic contact angles and contact angle hysteresis, thermal, and electrical behavior have been evaluated with respect to their structure. The polymer films exhibited good thermal stability having the initial decomposition temperature above 450°C, glass transition temperature in the range of 223?228°C, and low‐dielectric constant in the range of 2.64?3.16. Two subglass transitions, γ and β, were evidenced by dynamic mechanical analysis and dielectric spectroscopy. The surface morphology and the roughness were investigated by atomic force microscopy and scanning electron microscopy. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers 相似文献
57.
Florin Mingireanu Lucian P. Georgescu Gabriel Murariu Ionut Mocanu Marius Stoia-Djeska Nicolae Jula 《Surface Engineering and Applied Electrochemistry》2014,50(3):267-274
This paper presents an innovative method to increase the regression speed of a solid fuel grain by using oxidizer doping. The results obtained on a propulsion application showing the performance parameters as an output of a numerical model are provided. Two models are given that predict the regression speed increase for embedding wires and for oxidizer doping with a factor of ~2 to 3. Also, it is shown that this increase of the regression speed by using a low oxidizer doping percentage, which is based on the assumption that at a higher doping rate the combustion instabilities, can lead to detonations. Next, a thermochemical model for the combustion within the oxidizer doping model is afforded. For this model, the burn is assumed to take place around the surface of each of the oxidizer particles, being composed of two different burning processes: one is the burning on the surface of the solid fuel grain and the other is the burning between the solid fuel and the solid oxidizer. For a non-doped fuel grain, the burning takes place only on the surface of the fuel grain. Finally, a potential application of such propulsion units to small satellite launchers is presented, and a case study of such a vehicle intended to place a 50 kg payload on a low earth orbit (300 to 500 km altitude) is described. The modelling proposed is based on the assumption that the use of solid methane makes this launcher environmentally friendly. 相似文献
58.
Gillian R. Hayes Sen Hirano Gabriela Marcu Mohamad Monibi David H. Nguyen Michael Yeganyan 《Personal and Ubiquitous Computing》2010,14(7):663-680
Interventions to support children with autism often include the use of visual supports, which are cognitive tools to enable learning and the production of language. Although visual supports are effective in helping to diminish many of the challenges of autism, they are difficult and time-consuming to create, distribute, and use. In this paper, we present the results of a qualitative study focused on uncovering design guidelines for interactive visual supports that would address the many challenges inherent to current tools and practices. We present three prototype systems that address these design challenges with the use of large group displays, mobile personal devices, and personal recording technologies. We also describe the interventions associated with these prototypes along with the results from two focus group discussions around the interventions. We present further design guidance for visual supports and discuss tensions inherent to their design. 相似文献
59.
Marius Zimand 《Theory of Computing Systems》2010,46(4):707-722
The randomness rate of an infinite binary sequence is characterized by the sequence of ratios between the Kolmogorov complexity
and the length of the initial segments of the sequence. It is known that there is no effective procedure that transforms one
input sequence into another sequence with higher randomness rate. By contrast, we display such a uniform effective procedure
having as input two independent sequences with positive but arbitrarily small constant randomness rate. Moreover the transformation
is a truth-table reduction and the output has randomness rate arbitrarily close to 1. 相似文献
60.
Judit Molera Trinitat Pradell Nati Salvadó Marius Vendrell-Saz 《Journal of the American Ceramic Society》1999,82(10):2871-2875
Tin oxide (SnO2 ) particles that are a few hundred nanometers in size and are embedded in a lead glaze act as a white opacifier. The insolubility of SnO2 particles in a lead glaze is responsible for this microstructure. Although it is assumed that SnO2 particles do not react during the glaze formation, we demonstrate that the development of metastable phases prior to the fusion of the PbO-SiO2 -SnO2 mixture allows the SnO2 particles to react and then recrystallize subsequent to the fusion of the mixture. The recrystallization of SnO2 occurs during heating and/or cooling until the temperature is sufficiently low and/or the tin supply is exhausted. 相似文献