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Julia Radwan-Pragłowska Marek Piątkowski Diana Kitala Łukasz Janus Agnieszka Klama-Baryła Wojciech Łabuś 《国际聚合物材料杂志》2019,68(7):351-359
In this work we present a novel strategy for chitosan-based scaffolds. Chitosan is a versatile biopolymer obtained from waste biomass known of its favorable biological properties. Thus it can replace other polymers in the preparation of bioactive scaffolds. To increase its durability chitosan can be crosslinked into form of the hydrogel yet application of toxic crosslinkers may lead to loss of biocompability. Mesenchymal stem cells can be used in cell therapy for advanced wound treatment. However their culture requires special biomaterials application. In this article a novel microwave-assisted synthesis method for bioactive chitosan scaffolds is presented. 相似文献
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Marek Zukowski 《Journal of Modern Optics》2013,60(6-7):1151-1163
Abstract New types of Bell inequalities and new versions of the Bell theorem will be presented here. They lead to stronger constraints for local realistic theories than the standard inequalities. It will be shown that the fact that such inequalities can be violated indicates not only that we have to abandon classical concepts, but is also a direct indication that quantum states which lead to such violations can, without any further processing, like distillation, etc., be applied to perform tasks with efficiency unattainable for classical systems. Misinterpretations of Bell theorem will be discussed. On one hand, the root of some erroneous claims that there exists a local realistic model for EPR-Bell correlations will be exposed. On the other hand, over-interpretations using vague terms like quantum non-locality or just non-locality will be criticized. 相似文献
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The use of probiotic cultures in the production of Dutch-type cheeses did not lead to significant changes in their chemical composition but it lowered their acidity. The availability of calcium and magnesium analyzed by in vitro enzymatic hydrolysis was 19 and 35%, respectively; the availability of phosphorus was significantly higher, at >90%. The use of probiotic cultures significantly increased the availability of calcium (~2.5%), phosphorus (~6%), and magnesium (~18%). The in vitro method supports accurate determination of the effect of the Lactobacillus spp. cultures on the availability of mineral compounds ingested with Dutch-type cheese. 相似文献
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Marek Choratzy ;Marta Majcher ;Katarzyna Fedyszyn Urbanowicz ;Jedrzej Gtasek ;Maciej Gawlikowicz ;Tomasz Duniec 《材料科学与工程:中英文B版...》2014,(12):376-384
The authors compared their earlier results of the tumor biopsies performed under computer tomography (CT) guidance against the results of their recently modified-combined method of visualization and measurement of lung tumor parameters by CT imaging followed by US guided biopsy. In 238 (6.36%) of 3,745 patients in CT examination, the lung tumor was located peripherally, and obtaining histopathological confirmation was crucial to start the proper treatment. The patients were divided into two groups, the division was based on the biopsy method. Within the first group in I 18 patients, parietal lung tumor was confirmed and CT guided biopsy was performed. Within the second group, parietal lung tumor was confirmed in 120 patients and combined method of CT pre- biopsy planning and US guided biopsy were used. Pre-biopsy planning was performed using CT, measurements such as depth and distance of the tumor were made, obtained data were then saved on CT image and patient's skin was marked. Then obtained results were analyzed using test for two proportions. The analysis of the results confirmed the higher efficacy of the combined method taking into account the number of complications (p 〈 0.01) and diagnostic histopathological results (P 〈 0.001). Suggested innovative method, involving both CT pre-biopsy planning and US guided biopsy, allows to analyze simultaneously static CT and dynamic US images and it is considered to be an easy and effective method comparing to relying on static in nature CT images only. Our method is related to a lower complication risk rate. 相似文献
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Effect of the structure of polymer inclusion membranes on zn(II) transport from chloride aqueous solutions
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This article presents application of polymer inclusion membranes (PIM) containing polymer matrices: cellulose triacetate (CTA) or poly(vinyl) chloride (PVC), o‐nitrophenyloctyl ether (NPOE) as a plasticizer and phosphonium ionic liquids, i.e., trihexyltetradecylphosphonium chloride (Cyphos IL 101), bis(2,4,4‐trimethylpentyl)phosphinate (Cyphos IL 104) and tributyltetradecylphosphonium chloride (Cyphos IL 167), as carriers for Zn(II) transport from chloride medium. Cyphos IL167 application as an ion carrier in PIMs is reported for the first time. The membrane composition is found to affect Zn(II) transport significantly. SEM and AFM images show the differences in the surface morphology of PVC and CTA based membranes. Better transport abilities of CTA membranes (Zn(II) recovery factors exceed 80%) compared with those of PVC, indicate that the structural differences between the two polymers play a crucial role for the membrane permeability. The best initial flux and permeability coefficient are obtained for the membranes with Cyphos IL 101 and Cyphos IL 104 as carriers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42319. 相似文献
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The purpose of the study was to obtain a composite material with the self‐reinforced structure, which processing provide increased mechanical properties. The composites used in presented work were prepared from the two types of fiber mixtures, both were based on polypropylene fibers, the difference was in used cellulose or wood flour filler. Composites were prepared using the hot compaction method. The presented research describes the effect of the composite composition and processing conditions. The results include the static tension measurements, tensile impact tests and thermal analysis, including: DSC and DMTA. The structure has been studies using the SEM observations. Results of presented studies confirm the self‐reinforcing effect in obtained hybrid composites. It provides in the comparison to the standard wood polymer composites to the higher level of material reinforcement with lower amount of natural filler. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43283. 相似文献