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This study evaluated the use of pea (Pisum sativum) and cowpea (Vigna unguiculata) protein isolates (PPI and CPI) in the microencapsulation of ascorbic acid (AA), by spray drying. PPI and CPI were used pure or mixed with maltodextrin (M) as wall materials of AA. The process yield was improved from 66% to 86% by the addition of M (CPI/M and PPI/M); also, AA particles yield was 79%. The AA retention from the drying process was higher in PPI/M (69%) than in CPI/M (66%), and this was attributed to PPI proteolysis profile, demonstrated by the SDS–PAGE electrophoresis. Scanning electron microscopy revealed that AA particles were similarly spherical and shriveled. Mean particle sizes of PPI/M/AA and CPI/M/AA were 7 and 8 μm, respectively. This study showed the exploration of protein isolates from legumes in the development of a microparticulate system containing AA with great potential for use in human health.  相似文献   
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This paper reports an innovative development: concentrating gibbsite via reverse froth flotation in order to obtain a metallurgical-grade bauxite concentrate. Tailings from an industrial plant have undergone attrition scrubbing and desliming; the quartz silica contained in the tailings has undergone flotation. Starch was used as a depressant, and ether-amine as the cationic collector. Optimum pH is around 10.0. In pilot plant scale, a metallurgical-grade concentrate was obtained by assaying 42.3% available alumina with an alumina/insoluble silica mass ratio of 11.1. It contained the gibbsite and the iron and titanium bearing minerals. The concentrate was further upgraded by magnetic separation, leading to 54.0% available alumina, with an alumina/insoluble silica mass ratio of 12.6 at an overall available alumina recovery of 69.3% in the final concentrate (non-magnetic product).  相似文献   
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Benefiting from an understanding of economic and political markets includes recognition that engineers themselves can change these environments. Understanding healthcare and other technology markets includes an understanding that the markets sometimes don't just exist-they are altered and sometimes created by the technology. A less expensive and more effective means to monitor a disease such as PKU enhances the likelihood that insurers will cover costs of such monitoring. Recognizing the complexity of economics and policy recognizes that understanding sometimes comes in a burst of insight but more usually, and surely, builds in steps. Since improvements in quality of life are inadequately captured by the market, will political "markets" develop subsidies or regulations to encourage technology?.  相似文献   
105.
We investigated linear aliphatic dialkynes as a new structural class of i,i+7 linkers for the double‐click stapling of p53‐based peptides. The optimal combination of azido amino acids and dialkynyl linker length for MDM2 binding was determined. In a direct comparison between aliphatic and aromatic staple scaffolds, the aliphatic staples resulted in superior binding to MDM2 in vitro and superior p53‐activating capability in cells when using a diazidopeptide derived from phage display. This work demonstrates that the nature of the staple scaffold is an important factor that can affect peptide bioactivity in cells.  相似文献   
106.
Superparamagnetic nanoparticles are of high interest for therapeutic applications. In this work, nanoparticles of calcium-doped manganese ferrites (CaxMn1−xFe2O4) functionalized with citrate were synthesized through thermally assisted oxidative precipitation in aqueous media. The method provided well dispersed aqueous suspensions of nanoparticles through a one-pot synthesis, in which the temperature and Ca/Mn ratio were found to influence the particles microstructure and morphology. Consequently, changes were obtained in the optical and magnetic properties that were studied through UV-Vis absorption and SQUID, respectively. XRD and Raman spectroscopy studies were carried out to assess the microstructural changes associated with stoichiometry of the particles, and the stability in physiological pH was studied through DLS. The nanoparticles displayed high values of magnetization and heating efficiency for several alternating magnetic field conditions, compatible with biological applications. Hereby, the employed method provides a promising strategy for the development of particles with adequate properties for magnetic hyperthermia applications, such as drug delivery and cancer therapy.  相似文献   
107.
Enterocutaneous fistulas are not a minor problem in gastrointestinal tract surgery. Significant reduction of mortality and morbidity has been attained but they still remain high. The authors report three clinical cases in which they sealed and treated enterocutaneous, chronic, iatrogenic fistulas by injecting biological glue (N-Butil 2-Cyanoacrylate-Histoacryl) into the internal opening and fistulous tract. We believe that the technic we propose here, in the proper setting, may be an important contribution to the management of iatrogenic (postoperative) enterocutaneous fistulas.  相似文献   
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