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BackgroundFamilies in high mortality settings need regular contact with high quality services, but existing population-based measurements of contacts do not reflect quality. To address this, in 2012, we designed linked household and frontline worker surveys for Gombe State, Nigeria, Ethiopia, and Uttar Pradesh, India. Using reported frequency and content of contacts, we present a method for estimating the population level coverage of high quality contacts.ConclusionsMeasuring content of care to reflect the quality of contacts can reveal missed opportunities to deliver best possible health care.  相似文献   
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This study is concerned with characterizing cell-bound inducible beta-xylosidase produced by a strain of the thermophilic bacterial genus Thermomonospora. A crude preparation of this enzyme recovered from sonicated cells of this organism displayed high activity against paranitrophenyl-beta-xylopyranoside over a pH range of 5.5-7.7. The temperature optimum, based on a 30-min assay of activity, at pH 6.5 was 70 degrees C. The crude enzyme had a thermal half-life of approximately 1 week at 55 degrees C and pH 6.5. Xylose inhibited the enzyme. Values of K(m) and V(max) are estimated from the reaction rate data as 0.82 mM and 8 U/L, respectively.  相似文献   
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Although the color of indigo is strongly dependent on its environment, it is blue in most commonly encountered situations. Indigo's absorption at such long wavelengths for such a small molecule is unique, and I provide here an overview of the concepts advanced to account for this feature. A traditional valence–bond approach may be used to provide a reasonable qualitative explanation. A more rigorous, quantitative explanation is provided by molecular orbital methods of varying degrees of sophistication and several explanations have been proposed based on these models. Commonly, it is suggested that the important structural unit in determining color is based on the cross-conjugated “H-chromophore” concept. A second closely related explanation describes it as two symmetrically coupled merocyanine chains. Another proposal suggests that the basic chromophore may be interpreted as the aza analogue of two coupled anti aromatic-cyclopentadienyl ions. PiSYSTEM, a commercially available quantum mechanics program, has been used to provide a successful quantitative account of the colors of indigo and indirubin, a red isomer.  相似文献   
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The production of single cell protein (SCP) form ethanol is an interesting process to study from a biochemical engineering viewpoint. The cellular yield mainly depends upon the metabolic activity of the cells and the amount of substrate available. Fedbatch fermentations Were run in a 70 liter highly instrumented computer-coupled fermentor using Candida utilis. Respiratory quotient and culture fluorescence, measuring NADH, indicate by which pathway ethanol is utilized. By monitoring these parameters it is possible to control the ethanol concentration so that accumulation of acetate is minimized and the conversion of ethanol to cell mass is maximized.  相似文献   
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Relaxation dynamics is universal in science and engineering; its study serves to parameterize a system's response and to help identify a microscopic model of the processes involved. When measured data for a phenomenon cannot be fitted using one exponential, the choice of an alternative function to describe the decay becomes nontrivial. Here, we contrast two different, but fundamentally related approaches to fitting nontrivial decay curves; exponential decomposition and the gamma probability density function. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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In vitro selection has been an essential tool in the development of recombinant antibodies against various antigen targets. Deep sequencing has recently been gaining ground as an alternative and valuable method to analyze such antibody selections. The analysis provides a novel and extremely detailed view of selected antibody populations, and allows the identification of specific antibodies using only sequencing data, potentially eliminating the need for expensive and laborious low-throughput screening methods such as enzyme-linked immunosorbant assay. The high cost and the need for bioinformatics experts and powerful computer clusters, however, have limited the general use of deep sequencing in antibody selections. Here, we describe the AbMining ToolBox, an open source software package for the straightforward analysis of antibody libraries sequenced by the three main next generation sequencing platforms (454, Ion Torrent, MiSeq). The ToolBox is able to identify heavy chain CDR3s as effectively as more computationally intense software, and can be easily adapted to analyze other portions of antibody variable genes, as well as the selection outputs of libraries based on different scaffolds. The software runs on all common operating systems (Microsoft Windows, Mac OS X, Linux), on standard personal computers, and sequence analysis of 1–2 million reads can be accomplished in 10–15 min, a fraction of the time of competing software. Use of the ToolBox will allow the average researcher to incorporate deep sequence analysis into routine selections from antibody display libraries.  相似文献   
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Groups of Fischer 344 rats were injected intravenously with Bacillus anthracis culture supernatant containing crude anthrax toxin. Times to death of rats given identical toxin preparations varied directly with the weights of the rats (P = 0.0001). In contrast to previous reports, the data indicate that rat weight must be taken into account during in vivo assays of anthrax lethal toxin activity.  相似文献   
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The great challenges for researchers working in the field of vaccinology are optimizing DNA vaccines for use in humans or large animals and creating effective single-dose vaccines using appropriated controlled delivery systems. Plasmid DNA encoding the heat-shock protein 65 (hsp65) (DNAhsp65) has been shown to induce protective and therapeutic immune responses in a murine model of tuberculosis (TB). Despite the success of naked DNAhsp65-based vaccine to protect mice against TB, it requires multiple doses of high amounts of DNA for effective immunization. In order to optimize this DNA vaccine and simplify the vaccination schedule, we coencapsulated DNAhsp65 and the adjuvant trehalose dimycolate (TDM) into biodegradable poly (DL-lactide-co-glycolide) (PLGA) microspheres for a single dose administration. Moreover, a single-shot prime-boost vaccine formulation based on a mixture of two different PLGA microspheres, presenting faster and slower release of, respectively, DNAhsp65 and the recombinant hsp65 protein was also developed. These formulations were tested in mice as well as in guinea pigs by comparison with the efficacy and toxicity induced by the naked DNA preparation or BCG. The single-shot prime-boost formulation clearly presented good efficacy and diminished lung pathology in both mice and guinea pigs.  相似文献   
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