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Reliable and timely information on socio-economic status and divides is critical to social and economic research and policing. Novel data sources from mobile communication platforms have enabled new cost-effective approaches and models to investigate social disparity, but their lack of interpretability, accuracy or scale has limited their relevance to date. We investigate the divide in digital mobile service usage with a large dataset of 3.7 billion time-stamped and geo-referenced mobile traffic records in a major European country, and find profound geographical unevenness in mobile service usage—especially on news, e-mail, social media consumption and audio/video streaming. We relate such diversity with income, educational attainment and inequality, and reveal how low-income or low-education areas are more likely to engage in video streaming or social media and less in news consumption, information searching, e-mail or audio streaming. The digital usage gap is so large that we can accurately infer the socio-economic status of a small area or even its Gini coefficient only from aggregated data traffic. Our results make the case for an inexpensive, privacy-preserving, real-time and scalable way to understand the digital usage divide and, in turn, poverty, unemployment or economic growth in our societies through mobile phone data.  相似文献   
123.
Little is known about the effect of lead on the activity of the vacuolar K+ channels. Here, the patch-clamp technique was used to compare the impact of lead (PbCl2) on the slow-activating (SV) and fast-activating (FV) vacuolar channels. It was revealed that, under symmetrical 100-mM K+, the macroscopic currents of the SV channels exhibited a typical slow activation and a strong outward rectification of the steady-state currents, while the macroscopic currents of the FV channels displayed instantaneous currents, which, at the positive potentials, were about three-fold greater compared to the one at the negative potentials. When PbCl2 was added to the bath solution at a final concentration of 100 µM, it decreased the macroscopic outward currents of both channels but did not change the inward currents. The single-channel recordings demonstrated that cytosolic lead causes this macroscopic effect by a decrease of the single-channel conductance and decreases the channel open probability. We propose that cytosolic lead reduces the current flowing through the SV and FV channels, which causes a decrease of the K+ fluxes from the cytosol to the vacuole. This finding may, at least in part, explain the mechanism by which cytosolic Pb2+ reduces the growth of plant cells.  相似文献   
124.
Gamma rays and electrons with kinetic energy up to 10 MeV are routinely used to sterilize biomaterials. To date, the effects of irradiation upon human acellular dermal matrices (hADMs) remain to be fully elucidated. The optimal irradiation dosage remains a critical parameter affecting the final product structure and, by extension, its therapeutic potential. ADM slides were prepared by various digestion methods. The influence of various doses of radiation sterilization using a high-energy electron beam on the structure of collagen, the formation of free radicals and immune responses to non-irradiated (native) and irradiated hADM was investigated. The study of the structure changes was carried out using the following methods: immunohistology, immunoblotting, and electron paramagnetic resonance (EPR) spectroscopy. It was shown that radiation sterilization did not change the architecture and three-dimensional structure of hADM; however, it significantly influenced the degradation of collagen fibers and induced the production of free radicals in a dose-dependent manner. More importantly, the observed effects did not disrupt the therapeutic potential of the new transplants. Therefore, radiation sterilization at a dose of 35kGy can ensure high sterility of the dressing while maintaining its therapeutic potential.  相似文献   
125.
A series of nanostructured titanium oxide particles were synthesized by a simple wet chemical method and characterized by means of small-angle x-ray scattering (SAXS)/wide-angle x-ray scattering (WAXS), atomic force microscope (AFM), scanning electron microscope (SEM), transmission electron microscope (TEM), thermal analysis, and rheometry. Tetrabutyl titanate (TBT) and ethylene glycol (EG) can be combined to form either TiO(x) nanowires or smooth nanorods, and the molar ratio of TBT:EG determines which of these is obtained. Therefore, TiO(x) nanorods with a highly rough surface can be obtained by hydrolysis of TBT with the addition of cetyl-trimethyl-ammonium bromide (CTAB) as surfactant in an EG solution. Furthermore, TiO(x) nanorods with two sharp ends can be obtained by hydrolysis of TBT with the addition of salt (LiCl) in an EG solution. The AFM results show that the TiO(x) nanorods with rough surfaces are formed by the self-assembly of TiO(x) nanospheres. The electrorheological (ER) effect was investigated using a suspension of titanium oxide nanowires or nanorods dispersed in silicone oil. Oil suspensions of titanium oxide nanowires or nanorods exhibit a dramatic reorganization when submitted to a strong DC electric field and the particles aggregate to form chain-like structures along the direction of applied electric field. Two-dimensional SAXS images from chains of anisotropically shaped particles exhibit a marked asymmetry in the SAXS patterns, reflecting the preferential self-assembly of the particles in the field. The suspension of rough TiO(x) nanorods shows stronger ER properties than that of the other nanostructured TiO(x) particles. We find that the particle surface roughness plays an important role in modification of the dielectric properties and in the enhancement of the ER effect.  相似文献   
126.
In an era of ever‐increasing energy demands, a promising technology is being developed: the use of oleaginous microorganisms such as Yarrowia lipolytica to convert waste materials into biofuels. Here, we constructed two Y. lipolytica strains that displayed both increased lipid accumulation and more efficient use of biomass‐derived sugars, including glucose, fructose, galactose and inulin. The first strain, Y. lipolytica YLZ150, was derived from the French wild‐type strain W29. It had inhibited triacylglycerol mobilization (?tgl4 ) and β‐oxidation (?pox1–6 ), and it overexpressed GPD1 , DGA2 , HXK1 , the native Leloir pathway, SUC2 from Saccharomyces cerevisiae and INU1 from Kluyveromyces marxianus . The second strain, Y. lipolytica Y4779, was derived from the Polish A‐101 strain. It had inhibited β‐oxidation (?mfe2 ) and overexpressed GPD1 , DGA1 , HXK1 , YHT3, SUC2 and INU1 . In the first experiment, strain YLZ150 was batch‐cultured in media containing different hexoses; the highest values for lipid concentration and yield of lipids from the substrate were obtained using fructose (20.3 g dm?3 and 0.14 g g?1, respectively). In the second experiment, we grew the two strains in fed‐batch cultures to examine lipid biosynthesis from inulin (a fructose polymer). For Y4779, the lipid concentration was 10.3 g dm?3 and the yield of lipids from substrate was 0.07 g g?1; in contrast, for YLZ150, these values were 24 g dm?3 and 0.16 g g?1, respectively. The YLZ150 strain is thus able to efficiently exploit glucose, fructose, galactose, sucrose and inulin for lipid biosynthesis. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
127.
128.
Milk protein concentrate powder with 85% protein (MPC85) was jet‐milled to give 2 particle size distributions (that is, JM‐Coarse and JM‐Fine) or freeze‐dried (FD), in order to improve the functional properties of MPC85 for use in high‐protein nutrition (HPN) bars. Volume‐weighted mean diameter decreased from 86 μm to 49, 22, and 8 μm in FD, JM‐Coarse, and JM‐Fine, respectively (P < 0.05). The MPC85 powders modified by jet‐milling and freeze‐drying were significantly denser than the control MPC85 (P < 0.05). Volume of occluded air in the modified powders decreased (P < 0.05) by an order of magnitude, yet only FD possessed a lower volume of interstitial air (P < 0.05). Particle size reduction and freeze‐drying MPC85 decreased its water holding capacity and improved its dispersibility by at least 20%. Contact angle measurements showed that these modifications increased initial hydrophobicity and did not improve wettability. HPN bars made from JM‐Fine or FD were firmer by 40 or 17 N, respectively, than the control on day 0 (P < 0.05). HPN bar maximum compressive force increased by 38%, 33%, and 242% after 42 d at 32 °C when formulated with JM‐Fine, FD, or control MPC85, respectively. HPN bars prepared with JM‐Fine were less crumbly than those formulated with control or FD MPC85. Physically altering the particle structure of MPC85 improved its ability to plasticize within HPN bars and this improved their cohesiveness and textural stability.  相似文献   
129.
Milk protein concentrates with more than 80% protein (that is, MPC80) are underutilized as the primary protein source in high‐protein nutrition bars as they impart crumbliness and cause hardening during storage. High‐protein nutrition bar texture changes are often associated with internal protein aggregations and macronutrient phase separation. These changes were investigated in model high‐protein nutrition bars formulated with MPC80 and physically modified MPC80s. High‐protein nutrition bars formulated with extruded MPC80s hardened slower than those formulated with toasted or unmodified MPC80. Extruded MPC80 had reduced free sulfhydryl group exposure, whereas measurable increases were seen in the toasted MPC80. High‐protein nutrition bar textural performance may be related to the number of exposed free sulfhydryl groups in MPC80. Protein aggregations resulting from ingredient modification and high‐protein nutrition bar storage were studied with sodium dodecyl sulfate polyacrylamide gel electrophoresis. Disulfide‐based protein aggregations and changes in free sulfhydryl concentration were not consistently relatable to high‐protein nutrition bar texture change. However, the high‐protein nutrition bars formulated with extruded MPC80 were less prone to phase separations, as depicted by confocal laser scanning microscopy, and underwent less texture change during storage than those formulated with toasted or unmodified MPC80.  相似文献   
130.
Abstract

A new apodization principle is introduced, according to which the amplitude function is realized as a varying diffraction efficiency of the multistep phase diffractive element. A proper modification of the phase-step heights within the apodization region allows one to redirect light from the main diffraction order into its conjugate, simultaneously avoiding the presence of light in the two nearest neighbouring orders. The analysis is confirmed by the simulation results.  相似文献   
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