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The region of the investigated receptor is situated in the southern part of the Adriatic Sea in the Mediterranean. The measuring station is located on the seashore, which, being considered as a border area, is representative for the qualitative and quantitative estimation of the influence of marine and continental aerosols on the content of major ions in precipitation. In the sampling period, precipitation in the region of the investigated receptor was more abundant during the summer and autumn than during the winter and spring. The most frequent precipitation heights were up to 20 mm, while high precipitation came exclusively from the continental region. The results of the measurements of ions readily soluble in water were used for the differentiation of marine from continental contributions of primary and secondary aerosols to their content in the precipitation. Using PCA, it was shown that main contribution of Cl(-), Na(+) and Mg(2+) came from primary marine aerosols, while the contribution from continental sources was dominant for the content of SO(4)(2-), NO(3)(-), NH(4)(+) and Ca(2+) in the precipitation. The continental origin of Ca(2+) was from a primary source, while SO(4)(2-), NO(3)(-) and NH(4)(+) were representatives of secondary aerosols produced by reactions between acid oxides and alkaline species in the atmosphere, but SO(4)(2-) and NO(3)(-) also exist in the precipitation as free acids. The origin of the trace elements Cd, Cu, Pb and Zn in the precipitation came from anthropogenic emission sources. The results obtained in this work are based on experimental data from 609 samples collected during the period 1995-2000.  相似文献   
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In the present study, we studied the effect of apolipoprotein A-1 (APOA1) on the spatial and molecular characteristics of bone marrow adipocytes, using well-characterized ApoA1 knockout mice. APOA1 is a central regulator of high-density lipoprotein cholesterol (HDL-C) metabolism, and thus HDL; our recent work showed that deficiency of APOA1 increases bone marrow adiposity in mice. We found that ApoA1 deficient mice have greatly elevated adipocytes within their bone marrow compared to wild type counterparts. Morphologically, the increased adipocytes were similar to white adipocytes, and displayed proximal tibial-end localization. Marrow adipocytes from wild type mice were significantly fewer and did not display a bone-end distribution pattern. The mRNA levels of the brown/beige adipocyte-specific markers Ucp1, Dio2, Pat2, and Pgc1a; and the expression of leptin were greatly reduced in the ApoA1 knock-out in comparison to the wild-type mice. In the knock-out mice, adiponectin was remarkably elevated. In keeping with the close ties of hematopoietic stem cells and marrow adipocytes, using flow cytometry we found that the elevated adiposity in the ApoA1 knockout mice is associated with a significant reduction in the compartments of hematopoietic stem cells and common myeloid, but not of the common lymphoid, progenitors. Moreover, the ‘beiging’-related marker osteopontin and the angiogenic factor VEGF were also reduced in the ApoA1 knock-out mice, further supporting the notion that APOA1—and most probably HDL-C—regulate bone marrow microenvironment, favoring beige/brown adipocyte characteristics.  相似文献   
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Nowadays a large variety of applications are based on solid nanoparticles dispersed in liquids—so called nanofluids. The interaction between the fluid and the nanoparticles plays a decisive role in the physical properties of the nanofluid. A novel approach based on the nonradiative energy transfer between two small luminescent nanocrystals (GdVO4:Nd3+ and GdVO4:Yb3+) dispersed in water is used in this work to investigate how temperature affects both the processes of interaction between nanoparticles and the effect of the fluid on the nanoparticles. From a systematic analysis of the effect of temperature on the GdVO4:Nd3+ → GdVO4:Yb3+ interparticle energy transfer, it can be concluded that a dramatic increase in the energy transfer efficiency occurs for temperatures above 45 °C. This change is properly explained by taking into account a crossover existing in diverse water properties that occurs at about this temperature. The obtained results allow elucidation on the molecular arrangement of water molecules below and above this crossover temperature. In addition, it is observed that an energy transfer process is produced as a result of interparticle collisions that induce irreversible ion exchange between the interacting nanoparticles.  相似文献   
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Multimedia Tools and Applications - In recent years, the rapid development of diverse media has been evident in disparate fields such as consumer electronics, automotive infotainment and healthcare...  相似文献   
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This paper addresses the problems of coding complexity and power consumption in a recent contribution on integer codes.  相似文献   
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A novel readout procedure for a mercury sensor has been proposed. The sensor is based on the surface adsorption. Mercury vapor is adsorbed at the surface of a thin gold layer patterned into four meanders which are connected into a Wheatstone bridge configuration. Sensing is achieved by the resistivity change of the gold film during mercury adsorption. Direct output from the sensor is electric voltage. It takes an additional procedure to convert voltage to mercury concentration. This type of sensor is improved by introducing continuous readout procedure for the voltage–concentration conversion. By using this readout procedure it is possible to monitor mercury vapor concentration as a function of time. Readout is based on the Langmuir time–dependent adsorption theory. This paper illustrates a practical implementation of the new readout procedure.  相似文献   
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