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141.
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Mrton Richrd Szab Mrton Pipicz Tams Csont Csaba Csonka 《International journal of molecular sciences》2020,21(24)
There is a growing body of evidence showing the importance of physical activity against acute ischemic events in various organs. Ischemia/reperfusion injury (I/R) is characterized by tissue damage as a result of restriction and subsequent restoration of blood supply to an organ. Oxidative stress due to increased reactive oxygen species formation and/or insufficient antioxidant defense is considered to play an important role in I/R. Physical activity not only decreases the general risk factors for ischemia but also confers direct anti-ischemic protection via myokine production. Myokines are skeletal muscle-derived cytokines, representing multifunctional communication channels between the contracting skeletal muscle and other organs through an endocrine manner. In this review, we discuss the most prominent members of the myokines (i.e., brain-derived neurotrophic factor (BDNF), cathepsin B, decorin, fibroblast growth factors-2 and -21, follistatin, follistatin-like, insulin-like growth factor-1; interleukin-6, interleukin-7, interleukin-15, irisin, leukemia inhibitory factor, meteorin-like, myonectin, musclin, myostatin, and osteoglycin) with a particular interest in their potential influence on reactive oxygen and nitrogen species formation or antioxidant capacity. A better understanding of the mechanism of action of myokines and particularly their participation in the regulation of oxidative stress may widen their possible therapeutic use and, thereby, may support the fight against I/R. 相似文献
144.
Laszlo Racz Daniel Fozer Tibor Nagy Andras Jozsef Toth Eniko Haaz Janka Ariella Tarjani Anita Andre Asmaa Selim Nora Valentinyi Laszlo Tamas Mika Csaba Deak Peter Mizsey 《Clean Technologies and Environmental Policy》2018,20(9):2013-2024
Biodiesel production showed an immense increase worldwide in the past decade. Since the comprehensive analyses of biodiesel production processes and their comparative evaluation are both rare and not informative enough, e.g., for scientists and decision makers, in this work different, favored biodiesel production alternatives (rapeseed, soybean and palm) are analyzed from multiple viewpoints and compared. A complex examination is carried out with Political, Economic, Social, Technological, Legal and Environmental (PESTLE) analysis, where cradle-to-grave life cycle analysis is incorporated and performed within PESTLE factors. Life cycle inventory is set up based on Ecoinvent 3.3 database, while life cycle impact assessments are achieved by IPCC 2013, IMPACT 2002+, EPS 2000 and 2015dx methods. Monte Carlo analysis is also carried out in order to make certain about the robustness of input data. The investigated factors are weighted and ranked with multi-criteria decision analysis, wherein Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) method is applied for the comparison of alternatives. Our work presents a clear methodology for the comprehensive evaluation of biodiesel production alternatives, but the guideline can be followed for the evaluation of other production alternatives. In spite that the life cycle analysis shows the palm oil as the best alternative, the results of our comprehensive analysis show that the highest overall TOPSIS score can be achieved with rapeseed-based biodiesel pathway, especially for the European region. 相似文献
145.
The transport, trapping, and subsequent detrapping of charge in single crystals of semi-insulating cadmium zinc telluride
(CdZnTe) has been analyzed using multiple-scale perturbation techniques. This method has the advantage of not only treating
impulse charge generation typical in spectroscopic analysis, but also a large class of continuous generation sources more
relevant to high-flux x-ray imaging applications. We first demonstrate that the multiple-scale solutions obtained for small-current
transients induced by an impulse generation of charge are consistent with well-known exact solutions. Further, we use the
multiple-scale solutions to derive an analytic generalization of the Hecht equation that incorporates detrapping over times
much longer than the carrier transit time (i.e., delayed signal components). The method is then applied to a continuous charge
generation source that approximates that of an x-ray source. The space–time solutions obtained are relevant to detector design
in high-flux x-ray imaging applications. Throughout this work the multiple-scale solutions are compared with exact solutions
as well as full numerical solutions of the fundamental charge conservation equations. 相似文献
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Michele Pra György Csaba Christoph Erlen Paolo Lugli 《Journal of Computational Electronics》2008,7(3):146-150
As passive crossbar memories contain no amplifying/signal restoring components, their scalability, reliability and speed depends
exclusively on the quality of diodes, fuse/antifuse elements and interconnections that constitute them. This paper presents
a computational study of ZnO-based Schottky diodes which are thought to be a good candidate for the junction of a crossbar
memory, mainly due to their limited thermal budget which guarantees the compatibility with Silicon technology. The simulation
shows that the diode characteristics are indeed suitable for their use as junctions. A circuit level simulation demonstrates
that optimized ZnO devices would allow the realization of many-megabit memory arrays. 相似文献
148.
Csaba P. Keszthelyi 《Electrochimica acta》1981,26(9):1261-1263
1:2 molar ratio 1-methylpyridinium chloride—aluminium chloride and 1:2 m/o 1-butylpyridinium chloride—aluminium chloride melts offer a suitable solvent/supporting electrolyte medium for electrochemical studies of organic as well as inorganic solutes. Novel radical cation formation due to homogeneous electron transfer has also been observed for aromatic compounds having an oxidation potential more negative than + 1.5 V vs sce. Formation of the radical cations via homogeneous electron transfer has been confirmed by electrochemical, uv-vis spectroscopic, and esr techniques. The cation formation depends on the melt acidity, ie the 1-alkylpyridinium chloride—aluminium chloride ratio. These observations indicate that the 1:2 molar ratio 1-alkylpyridinium chloride—aluminium chloride melts are far more acidic than the corresponding 1:2 m/o alkali halide—aluminium chloride fused salt systems. 相似文献
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150.
Most game programs have a large number of parameters that are crucial for their performance. While tuning these parameters
by hand is rather difficult, efficient and easy to use generic automatic parameter optimisation algorithms are known only
for special problems such as the adjustment of the parameters of an evaluation function. The SPSA algorithm (Simultaneous
Perturbation Stochastic Approximation) is a generic stochastic gradient method for optimising an objective function when an
analytic expression of the gradient is not available, a frequent case in game programs. Further, SPSA in its canonical form
is very easy to implement. As such, it is an attractive choice for parameter optimisation in game programs, both due to its
generality and simplicity. The goal of this paper is twofold: (i) to introduce SPSA for the game programming community by
putting it into a game-programming perspective, and (ii) to propose and discuss several methods that can be used to enhance
the performance of SPSA. These methods include using common random numbers and antithetic variables, a combination of SPSA
with RPROP, and the reuse of samples of previous performance evaluations. SPSA with the proposed enhancements was tested in
some large-scale experiments on tuning the parameters of an opponent model, a policy and an evaluation function in our poker
program, MCRAISE. Whilst SPSA with no enhancements failed to make progress using the allocated resources, SPSA with the enhancements proved
to be competitive with other methods, including TD-learning; increasing the average payoff per game by as large as 0.19 times
the size of the amount of the small bet. From the experimental study, we conclude that the use of an appropriately enhanced
variant of SPSA for the optimisation of game program parameters is a viable approach, especially if no good alternative exist
for the types of parameters considered.
Editors: Michael Bowling · Johannes Fürnkranz · Thore Graepel · Ron Musick 相似文献