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排序方式: 共有2183条查询结果,搜索用时 15 毫秒
61.
Valeria Fedeli Alessandra Cucina Simona Dinicola Gianmarco Fabrizi Angela Catizone Luisa Gesualdi Simona Ceccarelli Abdel Halim Harrath Saleh H. Alwasel Giulia Ricci Paola Pedata Mariano Bizzarri Noemi Monti 《International journal of molecular sciences》2022,23(4)
Microgravity impairs tissue organization and critical pathways involved in the cell–microenvironment interplay, where fibroblasts have a critical role. We exposed dermal fibroblasts to simulated microgravity by means of a Random Positioning Machine (RPM), a device that reproduces conditions of weightlessness. Molecular and structural changes were analyzed and compared to control samples growing in a normal gravity field. Simulated microgravity impairs fibroblast conversion into myofibroblast and inhibits their migratory properties. Consequently, the normal interplay between fibroblasts and keratinocytes were remarkably altered in 3D co-culture experiments, giving rise to several ultra-structural abnormalities. Such phenotypic changes are associated with down-regulation of α-SMA that translocate in the nucleoplasm, altogether with the concomitant modification of the actin-vinculin apparatus. Noticeably, the stress associated with weightlessness induced oxidative damage, which seemed to concur with such modifications. These findings disclose new opportunities to establish antioxidant strategies that counteract the microgravity-induced disruptive effects on fibroblasts and tissue organization. 相似文献
62.
Klaus Kirschke Angela Mller Ernst Schmitz 《Advanced Synthesis \u0026amp; Catalysis》1985,327(6):893-898
New Azoolefines and their Acidic cleavage to Aryldiimines 3-Amino-1-aryl-3′,3′-dimethyl-pyrazolin-4-spiro-2′-oxiran-5-ones ( 3a – c ) undergo ring opening with methoxide forming methyl 3-amino-3-arylazo-propenoates ( 5a – c ). 5a – c are cleaved under acidic conditions. The main products of the cleavage of 5c with methanolic hydrochloric acid are nitrogen, 2, 4, 6-trichloro-benzen ( 6 ), 2, 4, 6-trichloro-aniline ( 9 ) and 2, 4, 6-trichlorophenylhydrazine ( 10 ). Intermediates of the cleavage of 5 are aryldiimines trapped with benzaldehyde as the corresponding benzhydrazides ( 12a , b ). 相似文献
63.
Giuseppa Di Bella Elisabetta Russo Angela Giorgia Potortì Emanuele Saija Hedi Ben Mansour 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(2):282-291
Farmed European sea bass (Dicentrarchus labrax, Linnaeus, 1758) were collected during 2016 from one Sicilian fish farm that uses two different rearing systems – sea cage and concrete tank – for determination of polychlorinated biphenyls (PCB), organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) residues by HRGC-MS/MS. Moreover, commercial feed was analysed. This study aimed to determine whether the different rearing systems affect the concentration of these compounds, and to assess the safety of cultured fish. PCBs represent the pollutants with the highest concentration; in particular, PCB138 and 153 have the highest concentration in almost all samples. Among OCPs, only 4,4′-DDE, 4,4′-DDD and 4,4′-DDT residues have been detected. Concerning PAHs, only fluorene and phenanthrene were detected, in both rearing systems. Although some residues of organic pollutants were found in the analysed samples, they were always below the MRLs, so the results suggest that farmed sea bass are safe for human consumption. 相似文献
64.
A viable way to develop optimal control strategies for multi-particle quantum systems is to consider the framework of time-dependent density functional theory (TDDFT), where low-dimensional nonlinear Schrödinger models are developed to compute the electronic density of related high-dimensional linear Schrödinger equations. Among these models, the Kohn-Sham TDDFT system allows to accommodate control mechanisms in the same potentials that appear in the original multi-dimensional Schrödinger equations, thus allowing a physical interpretation and a laboratory implementation. The purpose of this paper is the mathematical analysis of optimal control problems governed by the time-dependent Kohn-Sham (TDKS) equations including a control potential that has the purpose to drive the evolution of the electron density to perform given tasks. For the resulting optimal control problems, existence of optimal solutions is proved and their characterization as solutions of TDKS optimality systems is investigated. 相似文献
65.
This paper provides an introduction and an editorial to this special issue of River Research and Applications by documenting the contributions made by Professor Geoffrey Petts to our interdisciplinary understanding of the functioning of rivers and their floodplains and their sustainable management. We outline Geoff's career, which framed not only his research but its communication through his inspirational teaching but also included very high level and innovative contributions to the management and development of several UK universities. We then explain how and why Geoff was an outstanding interdisciplinary river scientist and how he communicated his science through both integrative books and book chapters and also research papers that developed eight complementary research themes. Lastly, we introduce the papers in this special issue and show how they provide inputs to Geoff's areas of research interest. 相似文献
66.
67.
Angela Pietrafesa Angela Capece Rocchina Pietrafesa Marina Bely Patrizia Romano 《Yeast (Chichester, England)》2020,37(11):609-621
The growing trend in the wine industry is the revaluation of the role of non-Saccharomyces yeasts, promoting the use of these yeasts in association with Saccharomyces cerevisiae. Non-Saccharomyces yeasts contribute to improve wine complexity and organoleptic composition. However, the use of mixed starters needs to better understand the effect of the interaction between these species during alcoholic fermentation. The aim of this study is to evaluate the influence of mixed starter cultures, composed by combination of different S. cerevisiae and Hanseniaspora uvarum strains, on wine characteristics and to investigate the role of cell-to-cell contact on the metabolites produced during alcoholic fermentation. In the first step, three H. uvarum and two S. cerevisiae strains, previously selected, were tested during mixed fermentations in natural red grape must in order to evaluate yeast population dynamics during inoculated fermentation and influence of mixed starter cultures on wine quality. One selected mixed starter was tested in a double-compartment fermentor in order to compare mixed inoculations of S. cerevisiae/H. uvarum with and without physical separation. Our results revealed that physical contact between S. cerevisiae and H. uvarum affected the viability of H. uvarum strain, influencing also the metabolic behaviour of the strains. Although different researches are available on the role of cell-to-cell contact-mediated interactions on cell viability of the strains included in the mixed starter, to our knowledge, very few studies have evaluated the influence of cell-to-cell contact on the chemical characteristics of wine. 相似文献
68.
Angela Bianco Francesco Fancello Virgilio Balmas Marco Dettori Andrea Motroni Giacomo Zara Marilena Budroni 《Journal of the Institute of Brewing》2019,125(2):222-229
Durum wheat (Triticum durum Desf.) has potential as an adjunct in brewing given its agronomic, chemical and technological properties. The aim of this work were to identify the cultivable microflora and evaluate the technological quality of the durum wheat variety ‘Senatore Cappelli’ grown and used by a craft brewery in Sardinia, Italy. The isolated bacterial strains were mainly rhizospheric (Kocuria rizophila, Microbacterium aerolatum and Bacillus pumilus) and associated with the microbiota of wheat (Staphylococcus spp.). None have been reported previously as spoilage species in brewing. The dominant yeast genera were Cryptococcus spp. and Rhodotorula spp., followed by Saccharomyces cerevisiae. The dominant filamentous fungus genera were Alternaria and Rhizopus. Low levels of mycotoxigenic Fusarium spp., Aspergillus spp. and Penicillium spp. were isolated. However, the levels of deoxynivalenol, T2‐HT2, fumonisin, aflatoxin and ochratoxin detected in the malt and grain were below the thresholds defined by European law. Malt obtained from raw grain showed interesting technological properties, but required specific malting parameters different from those of common wheat and barley. These data suggest that the use of locally grown durum wheat in brewing can increase sustainability and reduce costs, while reinforcing the link with the terroir and promoting reduced mycotoxin levels. © 2019 The Institute of Brewing & Distilling 相似文献
69.