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51.
Melinda E. Tth Brigitta Dukay Mria Pter Gbor Balogh Gerg Szcs gnes Zvara Gbor J. Szebeni Petra Hajdu Mrta Srkzy Lszl G. Pusks Zsolt Trk Tams Csont Lszl Vígh Mikls Sntha 《International journal of molecular sciences》2021,22(8)
Inappropriate nutrition and a sedentary lifestyle can lead to obesity, one of the most common risk factors for several chronic diseases. Although regular physical exercise is an efficient approach to improve cardiometabolic health, the exact cellular processes are still not fully understood. We aimed to analyze the morphological, gene expression, and lipidomic patterns in the liver and adipose tissues in response to regular exercise. Healthy (wild type on a normal diet) and hyperlipidemic, high-fat diet-fed (HFD-fed) apolipoprotein B-100 (APOB-100)-overexpressing mice were trained by treadmill running for 7 months. The serum concentrations of triglyceride and tumor necrosis factor α (TNFα), as well as the level of lipid accumulation in the liver, were significantly higher in HFD-fed APOB-100 males compared to females. However, regular exercise almost completely abolished lipid accumulation in the liver of hyperlipidemic animals. The expression level of the thermogenesis marker, uncoupling protein-1 (Ucp1), was significantly higher in the subcutaneous white adipose tissue of healthy females, as well as in the brown adipose tissue of HFD-fed APOB-100 females, compared to males. Lipidomic analyses revealed that hyperlipidemia essentially remodeled the lipidome of brown adipose tissue, affecting both the membrane and storage lipid fractions, which was partially restored by exercise in both sexes. Our results revealed more severe metabolic disturbances in HFD-fed APOB-100 males compared to females. However, exercise efficiently reduced the body weight, serum triglyceride levels, expression of pro-inflammatory factors, and hepatic lipid accumulation in our model. 相似文献
52.
All existing models of the rock freezing process are able to simulate the conductive heat transfer, but, however the convective terms are dominant in many cases, when water seepage also occurs. The origin of the majority of failures were caused by the effect of water seepage. A new integrated finite difference simulation technique has been developed to model rock freezing and water seepage simultaneously. The mathematical model, the base of numerical algorithm, the input and output data, the verification of the model using analytical solutions and a rather sophisticated practical case history are discussed in the paper. Finally, the first practical application of the model to support decisions on the proper system of freezing and on the proper combination with depressurization of water bearing layers is presented as well. 相似文献
53.
This paper describes the introduction of a new interaction paradigm to augmented reality applications. The everyday tool handling experience of working with pen and notebooks is extended to create a three dimensional two-handed interface, that supports easy-to-understand manipulation tasks in augmented and virtual environments. In the design step we take advantage from the freedom, given by our very low demands on hardware and augment form and functionality to this device. On the basis of examples from object manipulation, augmented research environments and scientific visualization we show the generality of applicability. Although being in the first stages implementation, we consider the wide spectrum of suitability for different purposes. 相似文献
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The general equilibrium theory — the most elaborated form of the value theory — is unable to integrate firms unless under the etiquette of 'techniques'. However, to study important economic questions, as for example growth, without firms is at most doubtful. As an alternative to the attempts aiming to rehabilitate firms (as for example Coase and the theory of organization) we propose to adopt a new approach which not only treats firms as real decision makers, i.e. they make irreversible economic decisions, but describes them from a dynamic point of view, i.e. an Onsagerian type of dynamics is developed. The main charateristics of this approach are the no-loss choice rule vis-à-vis the profit maximization, and the integration of quantity signals (and past experience) vis-à-vis the unique price signals. As a result, we are capable of separating three questions which are generally not distinguished in neoclassical economics, namely the evaluation (profitability), the choice of production level and that of trade. Hence, even in the linear technology and price taker case we have a meaningful answer as, for instance, the level of output. 相似文献
57.
Zsolt Pónya Ilaria Corsi Richárd Hoffmann Melinda Kovács Anikó Dobosy Attila Zoltán Kovács Mauro Cresti Beáta Barnabás 《International journal of molecular sciences》2014,15(12):23766-23791
During in vitro fertilization of wheat (Triticum aestivum, L.) in egg cells isolated at various developmental stages, changes in cytosolic free calcium ([Ca2+]cyt) were observed. The dynamics of [Ca2+]cyt elevation varied, reflecting the difference in the developmental stage of the eggs used. [Ca2+]cyt oscillation was exclusively observed in fertile, mature egg cells fused with the sperm cell. To determine how [Ca2+]cyt oscillation in mature egg cells is generated, egg cells were incubated in thapsigargin, which proved to be a specific inhibitor of the endoplasmic reticulum (ER) Ca2+-ATPase in wheat egg cells. In unfertilized egg cells, the addition of thapsigargin caused an abrupt transient increase in [Ca2+]cyt in the absence of extracellular Ca2+, suggesting that an influx pathway for Ca2+ is activated by thapsigargin. The [Ca2+]cyt oscillation seemed to require the filling of an intracellular calcium store for the onset of which, calcium influx through the plasma membrane appeared essential. This was demonstrated by omitting extracellular calcium from (or adding GdCl3 to) the fusion medium, which prevented [Ca2+]cyt oscillation in mature egg cells fused with the sperm. Combined, these data permit the hypothesis that the first sperm-induced transient increase in [Ca2+]cyt depletes an intracellular Ca2+ store, triggering an increase in plasma membrane Ca2+ permeability, and this enhanced Ca2+ influx results in [Ca2+]cyt oscillation. 相似文献
58.
Péter L. Sóti Lőrinc Telkes Zsolt Rapi András Tóth Tamás Vigh Zsombor K. Nagy Péter Bakó György Marosi 《Journal of Inorganic and Organometallic Polymers and Materials》2014,24(4):713-721
We report on the synthesis of a new, supported phase transfer catalyst and its asymmetric induction. An inorganic-polymer-supported chiral crown ether was prepared by the reaction between an optically active macrocycle deriving from methyl-α-d-glucopyranoside and silica nanofibres. The inorganic carrier of the catalyst has high specific surface area due to its nanofibrous structure, which is favourable for heterogeneous catalytic reactions. SiO2 fibres were electrospun from silica sol which was prepared via sol–gel reactions from tetraethylorthosilicate. The asymmetric Michael reaction of diethyl acetamidomalonate and β-nitrostyrene was selected for the comparison of the performance of various glucopyranoside-based macrocycles. The asymmetric inductions of macrocycles provided 20–99 % enantiomeric excess. A triethoxysilyl derivative was prepared from the highly enantioselective macrocycle in order to immobilize it on the surface of the silica nanofibres. The supported glucose based monoaza-15-crown-5 type macrocycle was characterized by X-ray photoelectron spectroscopy and compared with non-supported native crown ethers in the asymmetric Michael addition. The immobilized phase-transfer catalyst generated high enantiomeric excess (82 %) in spite of the fact that it was used in a three-phase reaction. 相似文献
59.
Thian-Khok YongSek-Sean Tan Chen-Hon NeeSeong-Shan Yap Yeh-Yee KeeGyörgy Sáfrán Zsolt Endre HorváthJason Moscatello Yoke-Khin YapTeck-Yong Tou 《Materials Letters》2012,66(1):280-281
Nanowires of indium tin oxide (ITO) were grown on catalyst-free amorphous glass substrates at relatively low temperature of 250 °C in argon and helium ambient by the Nd:YAG pulsed laser deposition technique. All the ITO samples showed crystalline structure due to substrate heating and the (400) X-ray diffraction peak became relatively stronger as the pressure was increased. The surface morphology was also changed from compact, polycrystalline thin-film layers to a dendritic layer consisting of nanowires for some limited pressure ranges. The transition from the normal thin-film structure to nanowires was likely due to the vapor-liquid-solid mechanism but under catalyst-free condition. These nanowires tended to grow perpendicularly on the glass substrate, as observed with the transmission electron microscopy (TEM), which also confirmed that these nanowires were crystalline. 相似文献
60.
Complying with the objectives of the European Union Water Framework Directive, the water management organisations of Hungary and Serbia launched a common project in 2010 in order to improve the status of the channel crossing the national border. During reconstruction planning they intended to take ecological aspects into consideration. Therefore the evaluation of ecological state has been carried out for the Baja-Bezdan channel complemented by on-the-spot monitoring and biological examinations. Such a detailed survey of the channel has no precedent to date. Besides the evaluation, ecology-based proposals were phrased, which not only serve the sustainable functioning of the channel, but also help to preserve its flora and fauna. 相似文献