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排序方式: 共有467条查询结果,搜索用时 78 毫秒
41.
Harsh Kumar Kanchan Bhardwaj Natlia Cruz-Martins Eugenie Nepovimova Patrik Oleksak Daljeet Singh Dhanjal Sonali Bhardwaj Reena Singh Chirag Chopra Rachna Verma Prem Parkash Chauhan Dinesh Kumar Kamil Ku
a 《Molecules (Basel, Switzerland)》2021,26(11)
The ingestion of contaminated water and food is known to cause food illness. Moreover, on assessing the patients suffering from foodborne disease has revealed the role of microbes in such diseases. Concerning which different methods have been developed for protecting food from microbes, the treatment of food with chemicals has been reported to exhibit an unwanted organoleptic effect while also affecting the nutritional value of food. Owing to these challenges, the demand for natural food preservatives has substantially increased. Therefore, the interest of researchers and food industries has shifted towards fruit polyphenols as potent inhibitors of foodborne bacteria. Recently, numerous fruit polyphenols have been acclaimed for their ability to avert toxin production and biofilm formation. Furthermore, various studies have recommended using fruit polyphenols solely or in combination with chemical disinfectants and food preservatives. Currently, different nanoparticles have been synthesized using fruit polyphenols to curb the growth of pathogenic microbes. Hence, this review intends to summarize the current knowledge about fruit polyphenols as antibacterial agents against foodborne pathogens. Additionally, the application of different fruit extracts in synthesizing functionalized nanoparticles has also been discussed. 相似文献
42.
Tijen Tanyalcin Diler Aslan Yusuf Kurtulmus Nalan Gökalp Kamil Kumanlioğlu 《Accreditation and quality assurance》2000,5(9):383-387
In this study the reference intervals for folate and vitamin B12 were estimated according to the National Committee for Clinical Laboratory Standards Approved Guideline C28-A and International
Federation of Clinical Chemistry recommendations. The study included 155 women and 124 men between ages 18–40. The health
status was confirmed by history, physical examination and a questionnaire. The central 95% reference intervals of serum folate
and vitamin B12 for women, determined non-parametrically, were found to be 3.9–18.1 ng/ml and 101–666.7 pg/ml, respectively.
The reference values of serum folate and vitamin B12 for men were also found to be 2,5–17.6 ng/ml and 100–699.57 pg/ml, respectively.
We did not observe subclass differences between females and males.
Received: 15 April 2000 · Accepted: 15 April 2000 相似文献
43.
Kamil Kaminski Marian Paluch R. Wrzalik Jerzy Ziolo Radoslav Bogoslovov C. Michael Roland 《Journal of polymer science. Part A, Polymer chemistry》2008,46(11):3795-3801
The polymerization and crosslinking of tetraethylene glycol dimethacrylate were induced by high pressure. The product was analyzed by both swelling experiments and broadband dielectric spectroscopy to determine the structure, with IR measurements used to follow the extent of reaction and its temperature dependence. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3795–3801, 2008 相似文献
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46.
In this Letter, we introduce an algorithm that overcomes limitations in shape measurement by holographic microscopic methods in cases of micro-optical elements with high NA, such as microlenses. The presented algorithm provides a simple method for shape reconstruction from interferometrically measured phase. The algorithm is based on the analysis of local ray transition through the measured object. We develop algorithms for holographic configurations working in transmission and reflection. The accuracy of the developed algorithms is proved by experiments and extensive simulations. We present an experiment in a holographic Mach-Zehnder configuration where we have measured and successfully reconstructed the height distribution of spherical and cylindrical microlenses with NA up to 0.3. 相似文献
47.
Dual Lukacs type characterizations of random variables in free probability are studied here. First, we develop a freeness property satisfied by Lukacs type transformations of free-Poisson and free-binomial non-commutative variables which are free. Second, we give a characterization of non-commutative free-Poisson and free-binomial variables by properties of first two conditional moments, which mimic Lukacs type assumptions known from classical probability. More precisely, our result is a non-commutative version of the following result known in classical probability: if U, V are independent real random variables, such that E(V(1−U)|UV) and E(V2(1−U)2|UV) are non-random then V has a gamma distribution and U has a beta distribution. 相似文献
48.
Sensitivity analysis provides useful information for equation-solving, optimization, and post-optimality analysis. However, obtaining useful sensitivity information for systems with nonsmooth dynamic systems embedded is a challenging task. In this article, for any locally Lipschitz continuous mapping between finite-dimensional Euclidean spaces, Nesterov’s lexicographic derivatives are shown to be elements of the plenary hull of the (Clarke) generalized Jacobian whenever they exist. It is argued that in applications, and in several established results in nonsmooth analysis, elements of the plenary hull of the generalized Jacobian of a locally Lipschitz continuous function are no less useful than elements of the generalized Jacobian itself. Directional derivatives and lexicographic derivatives of solutions of parametric ordinary differential equation (ODE) systems are expressed as the unique solutions of corresponding ODE systems, under Carathéodory-style assumptions. Hence, the scope of numerical methods for nonsmooth equation-solving and local optimization is extended to systems with nonsmooth parametric ODEs embedded. 相似文献
49.
Kamil Pawowicz Dominika Ludowicz Marta Kara
niewicz-ada Kamil Wdowiak Judyta Cielecka-Piontek 《Molecules (Basel, Switzerland)》2021,26(11)
The aim of the study is to evaluate the composition of lyophilisates obtained from Aloe arborescens leaf gel at the age of one to four years. The leaves were obtained from controlled crops, which allowed to exclude environmental factors as variables. It was confirmed that the lyophilisates obtained from different years of Aloe arborescens leaf gel varied in chromatographic analyses in terms of aloin A and aloenin A content (high-performance liquid chromatography with diode-array detection HPLC-DAD, high-performance liquid chromatography with tandem mass spectrometric detection HPLC-MS/MS). Similarly, while testing the phenolic acids and the sum of polyphenols content, differences in their levels in leaf gel lyophilisates from plants of individual years were observed (spectrophotometric method UV-VIS). The lyophilisate composition analysis showed that the one-year-old leaves were characterized by the highest content of aloin A and aloenin A. While the content of polyphenols, including phenolic acids, was higher in the leaves of older plants. The antioxidant potential of the tested lyophilisates was assessed simultaneously. Regardless of the research model used (CUPRAC, DPPH, ABTS), an antioxidant effect was noted for Aloe arborescens leaves. 相似文献
50.
Sans résuméThe first author is supported by the Scientific and Technical Research Council of Turkey, T.B.A.G-Ç2 相似文献