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Trypsin is often used to detach adhered cell subculture from a substrate. However, the proteolytic activity of trypsin may harm cells by cleaving the cell membrane proteins. The present study shows that cellular uptake of fluorescent nanoparticles is remarkably increased within 24 h after trypsinization. These results highlight the trypsin-induced protein digestion, provoking leaky cell plasma membrane which leads to the strongly enhanced cellular uptake of the nanoparticles. To prevent this effect, one should expose cells to the nanoparticle (NP)-based fluorescent labels at least 48 h after trypsinization.  相似文献   
53.
This review paper deals with colligated aspects of the BioPlus Project (ERA-ARD) implemented by Institute of Technology and Life Sciences (Poland) and Lithuanian University of Agriculture Institute of Agro-Engineering (Lithuania) in cooperation with National University of Life and Environmental Sciences of Ukraine Institute of Ecobiotechnologies and Bioenergy (Ukraine). The drawn inferences intended to be an auxiliary material for policy makers and can briefly indicate on direction of the regional development of rural Ukraine, focusing on: (i) country's specific and sub-regional assessments of renewable energy potentials and spheres of its application; (ii) identification of major barriers for the expansion of renewable energy technologies and policy guidance to overcome those barriers; (iii) recommendations for future actions and strategies concerning renewable energy in Ukraine. The article concludes that low contribution of bioenergy towards rural development is to a large extent driven by energy policy that inhibits the delivery and use of modern energy sources in rural Ukraine. Consequently, an incentive for achieving bioenergy's future that has greater relevance to development of the Ukraine's regions requires a mix of policy tools and institutional actions, briefly summarized in this paper.  相似文献   
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Journal of Materials Science - Tertiary fatty amide, namely N,N-dibutylundecenamide (DBUA), has been synthesized and evaluated as potential plasticizer for polyvinyl chloride (PVC). Homogeneous...  相似文献   
55.
The effect of context on the identification of common environmental sounds (e.g., dogs barking or cars honking) was tested by embedding them in familiar auditory background scenes (street ambience, restaurants). Initial results with subjects trained on both the scenes and the sounds to be identified showed a significant advantage of about five percentage points better accuracy for sounds that were contextually incongruous with the background scene (e.g., a rooster crowing in a hospital). Further studies with naive (untrained) listeners showed that this incongruency advantage (IA) is level-dependent: there is no advantage for incongruent sounds lower than a Sound/Scene ratio (So/Sc) of ?7.5 dB, but there is about five percentage points better accuracy for sounds with greater So/Sc. Testing a new group of trained listeners on a larger corpus of sounds and scenes showed that the effect is robust and not confined to a specific stimulus set. Modeling using spectral-temporal measures showed that neither analyses based on acoustic features, nor semantic assessments of sound-scene congruency can account for this difference, indicating the IA is a complex effect, possibly arising from the sensitivity of the auditory system to new and unexpected events, under particular listening conditions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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The paper presents the history and major results of research into resources, regime and quality of the surface water in the Ob basin, concentrated in such water bodies as glaciers, rivers, lakes, reservoirs and wetlands. Studies have long been carried out by such government agencies as the Hydrometeorological Service (Hydromet), the Ministry of Energy and others, engineering organizations, scientific research institutes of the academy of sciences and universities. The studies included large complex tasks aimed at economic development of the basin territory. By the 1980s, an expanded network of stationary hydrological observations existed, and basic information about the factors of resources formation, regime and surface water quality, as well as long-term dynamics of hydrological characteristics had been obtained. Today, a multidisciplinary and interdisciplinary approach to the hydrological cycle and geo-run-off at the global and regional scales is related to the changes in climate and the environment in general.  相似文献   
58.
A comparative study has been made of the processes involved in the consolidation of nanosized barium titanate powders by nonisothermal sintering at a linear heating rate, by rate-controlled sintering, and high-pressure sintering (up to 5 GPa). The use of linear heating and high-pressure has been found to be ineffective for obtaining nonporous ceramics (residual porosity of about 2%) and for miniziming grain growth. The application of external pressure does not prevent coalescent grain growth controlled by surface diffusion. When rate-controlled sintering is employed a densification/grain growth optimum can be attained with a relative density of 99.9% of the theoretical value and a grain size of about 100 nm.  相似文献   
59.
Speckle-field long- and short-exposure spatial correlation characteristics for target-in-the-loop (TIL) laser beam propagation and scattering in atmospheric turbulence are analyzed through the use of two different approaches: the conventional Monte Carlo (MC) technique and the recently developed brightness function (BF) method. Both the MC and the BF methods are applied to analysis of speckle-field characteristics averaged over target surface roughness realizations under conditions of 'frozen' turbulence. This corresponds to TIL applications where speckle-field fluctuations associated with target surface roughness realization updates occur within a time scale that can be significantly shorter than the characteristic atmospheric turbulence time. Computational efficiency and accuracy of both methods are compared on the basis of a known analytical solution for the long-exposure mutual correlation function. It is shown that in the TIL propagation scenarios considered the BF method provides improved accuracy and requires significantly less computational time than the conventional MC technique. For TIL geometry with a Gaussian outgoing beam and Lambertian target surface, both analytical and numerical estimations for the speckle-field long-exposure correlation length are obtained. Short-exposure speckle-field correlation characteristics corresponding to propagation in 'frozen' turbulence are estimated using the BF method. It is shown that atmospheric turbulence-induced static refractive index inhomogeneities do not significantly affect the characteristic correlation length of the speckle field, whereas long-exposure spatial correlation characteristics are strongly dependent on turbulence strength.  相似文献   
60.
We have used polished stainless steel as a mirror substrate to provide focusing of soft x rays in grazing-incidence reflection. The critical issue of the quality of the steel surface, polished and coated with gold, is discussed in detail. A comparison is made to a polished, gold-coated, electroless nickel surface, which provides a smoother finish. We used the surface height distributions, measured with an interferometric microscope and complemented by atomic-force microscope measurements, to compute power spectral densities and then to evaluate the surface roughness. The effects of roughness in reducing the specular reflectivity were verified by soft-x-ray measurements.  相似文献   
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