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351.
Food Biophysics - The aim of this study was to obtain a stable flaxseed oil (FSO)-in-water Pickering emulsion (PE) stabilized by chitosan (CS)-myristic acid (MA) nanogels and to investigate the...  相似文献   
352.
ABSTRACT: INTRODUCTION: Air guns, either modern or traditional models, are powerful weapons that are capable ofcausing serious or life-threatening injuries. CASE PRESENTATION: Here, we present a case of an air gun pellet injury, with the pellet trapped between the thyroidcartilage and the lining mucosa of a 58-year-old Iranian man. CONCLUSION: Entrapment of air gun pellet between thyroid cartilage and the lining mucosa, as presented inour case, may cause diagnostic challenges through the clinical presentation of slightodynophagia.  相似文献   
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Some microorganisms such as Sporoscarcina pasteurii precipitate calcium carbonate and are suitable for biocementation. This study aimed to investigate the effects of several factors including concentration of bacteria, chemical reactants, temperature, and pH on precipitation of calcium carbonate. The results showed that after 7 and 14 days of curing, the compressive strength of silty clay soil samples increased steadily as pH increased from 5 to 9. It was observed that pH plays an important role in biocementation. The highest compressive strength (i.e. 92 kPa) was observed when the soil was treated with 50 ml of bacterial solution after 14 days of curing. In addition, it was observed that the highest compressive strength of samples was achieved when the temperature was 40°C.  相似文献   
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Abstract: Paracoccus denitrificans strain PD1222 (from N. Harms, Vrije Universiteit, Amsterdam, The Netherlands), which is deficient in a host-specific restriction system, could be successfully used for (1) transposon Tn5 mutagenesis, (2) phage P1-mediated generalized transduction and (3) construction of Hfr strains. Experimental protocols and some properties of an ammonium transport-deficient mutant are described.  相似文献   
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We have carried out a nanosecond molecular dynamics simulation of an analogue of the ribonuclease C-peptide in water. The overall conformation has an extended region for the first three amino acids connected to an α-helix for residues 4–13, and this basic structure is preserved throughout the simulation, with helical hydrogen bonds present 87% of the time, on average. The final helical hydrogen bond is spontaneously broken and re-formed several times, providing a detailed picture of such winding/unwinding events. The simulation was used to estimate the effects of internal motion on proton nuclear Overhauser effect spectroscopy (NOESY) intensities for several classes of important cross peaks. Within the helical regions, the effects of internal motion vary only a little from one residue to another for backbone–backbone cross peaks, and the relevant correlation functions reach plateau values within about 50 ps. The spectral simulations show, however, that it may be difficult to establish a close quantitative connection between NOESY cross-peak volumes and measures of helical content. © 1993 John Wiley & Sons, Inc.  相似文献   
358.
State space methods have proven indispensable in neural data analysis. However, common methods for performing inference in state-space models with non-Gaussian observations rely on certain approximations which are not always accurate. Here we review direct optimization methods that avoid these approximations, but that nonetheless retain the computational efficiency of the approximate methods. We discuss a variety of examples, applying these direct optimization techniques to problems in spike train smoothing, stimulus decoding, parameter estimation, and inference of synaptic properties. Along the way, we point out connections to some related standard statistical methods, including spline smoothing and isotonic regression. Finally, we note that the computational methods reviewed here do not in fact depend on the state-space setting at all; instead, the key property we are exploiting involves the bandedness of certain matrices. We close by discussing some applications of this more general point of view, including Markov chain Monte Carlo methods for neural decoding and efficient estimation of spatially-varying firing rates.  相似文献   
359.
Maturation of rotavirus occurs in the endoplasmic reticulum (ER), a site of intracellular calcium storage. It was demonstrated previously that calcium plays an important role in the maturation of bovine rotavirus. We used protein A colloidal gold conjugated to an antibody to localize VP7, the outer capsid protein of the simian rotavius SA11, in permeabilized infected cells in the presence and absence of calcium in the culture medium. In medium containing calcium, VP7 was associated with nonenveloped double-shelled particles and membranous structures of the ER. In calcium-free medium, gold particles were not associated with the ER or with virus particles. Gold particles were distributed through the cytoplasm and were mainly associated with granular structures, but did not assemble onto virus particles. Our data suggest that in calcium-free medium, VP7 is synthesized, but does not remain incorporated, in the ER.  相似文献   
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