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1.
Some of the modern electronic and optoelectronic devices exploit ferrofluids contained in narrow gaps between two material plates. When the width of the gap becomes below a micrometer, the boundary plates are subjected to the Casimir force arising from the zero-point and thermal fluctuations of the electromagnetic field. These forces should be taken into account in microdevices with the dimensions decreased to below a micrometer. In this paper, we review recently performed calculations of the attractive Casimir pressure in three-layer systems containing a ferrofluid. We also find the ferrofluidic system where the Casimir pressure is repulsive. This result is obtained in the framework of the fundamental Lifshitz theory of van der Waals and Casimir forces. The conclusion is made that enhanced repulsion due to the presence of a ferrofluid may prevent from sticking of closely spaced elements of a microdevice.  相似文献   
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Elina 《中国宝石》2021,(1):54-55
从业十五载,从生产、行政到设计,多重身份的转变让他对珠宝有了更多的认识。以精巧细致追求完美,以灵动设计谋求共鸣。本期,就让我们跟随笔者的脚步,共同走近珠宝追梦人——黄颖聪的珠宝世界。梦幻宝石在黄颖聪的众多设计作品中,亚历山大变石可谓“常客”。  相似文献   
4.
Abstract

It has been argued that continuous-variable quantum teleportation at optical frequencies has not been achieved because the source used (a laser) was not ‘truly coherent’. Here it is shown that ‘true coherence’ is always illusory, as the concept of absolute time on a scale beyond direct human experience is meaningless. A laser is as good a clock as any other, even in principle, and this objection to teleportation experiments is baseless.  相似文献   
5.
Samples from three oil shows in Western Greece were studied following a suite of analytical geochemical procedures, aiming to reveal the origin of the organic matter and characterize its depositional environment. The authors’ findings were compared, and confirmed to a great extent, to geochemical results from previously published studies. Certain compositional differences exist between the three oil shows, reflecting different source rock and/or different facies. The influence of different analytical methodologies commonly used to separate compound groups (saturates, aromatics, resins, asphaltenes) on the obtained geochemical indices was also examined. The results demonstrate that bulk composition of maltenes, as well as most biomarker indices, are not affected significantly by the employed group-type separation procedures.  相似文献   
6.
In this paper, we demonstrate that interleaved sampling techniques can be used to characterize the Hamiltonian of a qubit and its environmental decoherence rate. The technique offers a significant advantage in terms of the number of measurements that are required to characterize a qubit. When compared to the standard Nyquist?CShannon sampling rate, the saving in the total measurement time for the interleaved method is approximately proportional to the ratio of the sample rates.  相似文献   
7.
Vitamin A deficiency (VAD) is a serious and widespread public health problem and the leading cause of preventable blindness in young children. It is also associated with increased rates of death from severe infections, especially in developing countries. Over the past 35 years, researchers have examined the numerous activities of vitamin A in different tissues of the human body. VAD can lead to a series of ocular symptoms, anemia, and weak resistance to infection, which can increase the severity of infectious diseases and the risk of death. Cell development, vision, growth, and normal metabolism are among the vital processes that are insufficiently supported in the presence of VAD. VAD leads to impaired tissue function especially during the developmental periods of infancy, childhood, pregnancy, and lactation. We describe a multidirectional model of VAD that demonstrates how VAD can have progressive, negative effects on vital processes of the human body throughout the life cycle. This model starts with impaired intake and its link to decreased absorption and digestion and includes outcomes such as malnutrition, inflammation, and improper growth processes, including possible mechanisms. Together, these clinical and biochemical manifestations contribute to the vicious cycle of VAD.  相似文献   
8.
The present level of the development of water/wastewater treatment methods, including advanced oxidation processes, allows removal of pollutants of wide spectrum under no question. However, the overall process cost and, especially, associated energy consumption are of increased importance. The present review presents the energy cost calculations made for the pollutants removal reported in more than forty publications for over the last four decades. Phenol, glycols, methyl-tert-butyl ether (MTBE), aliphatic unsaturated compounds, humic acids and lignin were considered as water pollutants for economic evaluation of their removal. Two oxidation processes, ozonation and Fenton reaction, were chosen as water treatment methods.  相似文献   
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Control of histone acetylation is a part of the epigenetic mechanism that regulates gene expression and chromatin architecture. The members of the bromodomain and extra terminal domain (BET) protein family are a group of epigenetic readers that recognize histone acetylation, whereas histone deacetyl‐ ases such as sirtuin 1 (SIRT1) function as epigenetic erasers. We observed that BET inhibition by the specific inhibitor JQ1 upregulated SIRT1 expression and activated SIRT1. Moreover, we observed that BET inhibition functionally reversed the pro‐inflammatory effect of SIRT1 inhibition in a cellular lung disease model. SIRT1 activation is desirable in many age‐related, metabolic and inflammatory diseases; our results suggest that BET protein inhibition would be beneficial in treatment of those conditions. Most importantly, our findings demonstrate a novel mechanism of SIRT1 activation by inhibition of the BET proteins.  相似文献   
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