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排序方式: 共有272条查询结果,搜索用时 15 毫秒
91.
Marine Lambert Abderrahim Benmoussa Idrissa Diallo Katheryn Ouellet-Boutin Vronique Dorval Nathalie Majeau Charles Joly-Beauparlant Arnaud Droit Alain Bergeron Bernard Têtu Yves Fradet Frdric Pouliot Patrick Provost 《International journal of molecular sciences》2021,22(18)
Using a modified RNA-sequencing (RNA-seq) approach, we discovered a new family of unusually short RNAs mapping to ribosomal RNA 5.8S, which we named dodecaRNAs (doRNAs), according to the number of core nucleotides (12 nt) their members contain. Using a new quantitative detection method that we developed, we confirmed our RNA-seq data and determined that the minimal core doRNA sequence and its 13-nt variant C-doRNA (doRNA with a 5′ Cytosine) are the two most abundant doRNAs, which, together, may outnumber microRNAs. The C-doRNA/doRNA ratio is stable within species but differed between species. doRNA and C-doRNA are mainly cytoplasmic and interact with heterogeneous nuclear ribonucleoproteins (hnRNP) A0, A1 and A2B1, but not Argonaute 2. Reporter gene activity assays suggest that C-doRNA may function as a regulator of Annexin II receptor (AXIIR) expression. doRNAs are differentially expressed in prostate cancer cells/tissues and may control cell migration. These findings suggest that unusually short RNAs may be more abundant and important than previously thought. 相似文献
92.
The association between memory self-efficacy (MSE) and memory performance is highly documented in the literature. However, previous studies have produced inconsistent results, and there is no consensus on the existence of a significant link between these two variables. In order to evaluate whether or not the effect size of the MSE–memory performance relationship in healthy adults is significant and to test several theory-driven moderators, we conducted a meta-analysis of published and unpublished studies. A random-effects model analysis of data from 107 relevant studies (673 effect sizes) indicated a low but significant weighted mean correlation between MSE and memory performance, r = .15, 95% CI [.13, .17]. In addition, the mean effect size was significantly moderated by the way MSE was assessed. Memory performance was more strongly related to concurrent MSE (perceived current ability to perform a given task) than it was to global MSE (perceived usual memory ability in general). Furthermore, we found marginally larger MSE–memory performance correlations when the memory situations used to assess MSE involved familiar stimuli. No effect of the method used to assess global MSE or domain MSE (memory rating vs. performance predictions) was found. The results also show that the resource demands of the memory tasks have a moderator effect, as the MSE–performance correlation is larger with free-recall and cued-recall tasks than it is with recognition tasks. Limitations (generalization issues, moderators not considered) and implications for future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
93.
WEI Xing & WU XiaoXing Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China Center for Coastal Ocean Science Technology Research Sun Yetsen University Guangzhou South China Sea Marine Prediction Center State Oceanic Administration Guangzhou 《中国科学:技术科学(英文版)》2011,(6)
One of eight gates of the Pearl River Estuary,the Yamen Inlet is a bedrock channel mouth connecting the Huangmao Sea and Yamen Channel.The wider water surfaces of the upper and lower reaches of the entrance produce a unique bidirectional asymmetrical jet system.Using observed hydrology and historical charts,the ECOMSED model was applied in morphodynamic analysis of the dynamic structures and dynamic equilibrium of the Yamen jet system and its effect on sedimentation.It was found that (1) the nonlinear inter... 相似文献
94.
Reinventing classics is a well-used yet complex design pattern. Indeed, a reinterpreted classic needs to relate to the original object while simultaneously challenging the initial model and providing a new and fresh look to the well-established classic. However, this design strategy remains understudied, and we aimed to contribute to the literature by addressing the lack of theoretical models for reinventing classics. Reinterpreting tradition is a key process for chefs in the culinary world. Our paper explores how design theories elucidate how chefs reinterpret classics and innovate in their kitchens by stepping away from tradition. Our contribution to the study of design is twofold. First, from a methodological point of view, we used a framework based on C–K theory and axiomatic design theory to conduct a comparative analysis of recipes for 30 dishes that were reinterpreted by the renowned chef Alain Ducasse. Second, our study identified two design regimes used by chefs to reinvent classics by focusing on the nature of the set of functions a recipe aims to fulfill. The first regime consists of retaining the same functions from the original recipe while changing the means to achieve them. The second requires changing the set of functions by removing old ones, adding new ones, and occasionally designing new ways to achieve the functions. 相似文献
95.
In recent years, a series of cruises have been launched by China Ocean Mineral Resources Research and Development Association (COMRA) to conduct hydrothermal activity investigation at mid-ocean ridges (MOR). Since the first active hydrothermal field at 49.6°E Southwest 相似文献
96.
Ira Katz Marine Pichelin Spyridon Montesantos Alexander Murdock Samuel Fromont Jose Venegas 《Aerosol science and technology》2017,51(2):214-223
In this article, we address a fundamental question regarding computational fluid dynamics (CFD) modeling within lung airways: does the inhaled volume during imaging have a significant effect on CFD computations of aerosol deposition? High resolution computed tomography (HRCT) images taken at mean lung volume (MLV) and at total lung capacity (TLC) obtained as part of a previous study of ventilation and aerosol deposition using positron emission tomography (PET) in challenged asthmatics were utilized to construct two airway models for each subject, and the differences in CFD calculated deposition metrics were subsequently quantified. These models included all the airway generations that could be rendered from the HRCT images. CFD calculations for three inhalation flow rates and four monodisperse aerosol sizes used images at MLV and at TLC from 24 volunteer subjects. Both large scale and detailed measures of particle deposition distribution were used in the analysis. The influence of lung volume during imaging is to increase airway dimensions in realistic models and thus reduce flow velocity and deposition due to impaction in the upper airways as calculated by CFD. However, large-scale deposition measures are confounded when the TLC models include deeper generations in the lung that increase the total airway deposition. These trends are modulated by the flow and particle characteristics of the aerosol, making consistent quantifiable differences between MLV and TLC difficult to predict unless both models consider the same anatomical airways.© 2017 American Association for Aerosol Research 相似文献
97.
DAI Lu & WENG ChengYu State Key Laboratory of Marine Geology Tongji University Shanghai China 《中国科学:技术科学(英文版)》2011,(2)
Pollen grains deposited in marine sediments are transported from land to sea by wind or surface water flows.We analyzed pollen collected from the air and seawater from the coast of the Yellow Sea near China and into the western Pacific Ocean between December 2008 and January 2009 during the cruise KX08-973.Results showed that abundant pollen grains of Artemisia and Chenopodiaceae were probably transported to the continental shelf of the East China Sea,the East Philippine Sea and the equatorial regions of th... 相似文献
98.
Kornél Nagy Karine Redeuil Sabine Lahrichi Marine Nicolas 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(5):712-721
This paper reports the first results on depleting certain organochlorines from vegetable oils without the use of any solvent in order to mitigate monochloropropanediol diesters (MCDPE). The concept is based on separating the organochlorines from the bulk oil by using trapping agents (e.g. monoacylglycerols) that can be easily separated from the oil. The process starts by mixing and homogenizing crude vegetable oils with the trapping agent and subsequently separating the trapping agent from the oil bulk via crystallization. The proof-of-concept of the approach is demonstrated on a spiked sunflower model system, solvent extracted crude sunflower oil, industrially produced crude soybean and corn oils. The depletion of organochlorines in the crude oils and its beneficial effect on the MCPDE content in the heat treated samples is measured by LC-MS. The depletion efficacy of the monitored organochlorines was estimated to be in the 60–95 % range. Both the melting point and polarity of the trapping agents affected the depletion efficacy of the organochlorines. Trapping agents with higher melting point and polarity, such as monostearin were more effective in comparison to high melting point but less polar agents such as palm stearin or agents rich in polar but low melting point monolinolein/monoolein. The effect of organochlorine depletion on the subsequent MPCDE levels in heat treated oil was in the range of 60–90 % reduction depending on the type of the studied oil. 相似文献
99.
100.
Marine Desage-El Murr Louis Fensterbank Cyril Ollivier 《Israel journal of chemistry》2017,57(12):1160-1169
This account describes some advances we have made in the field of iron catalysis. Two types of reactivity have been uncovered. Based on the use of an iron(II) precatalyst in the presence of NaBH4, the first one consists in a SET which can be useful for the reductive dehalogenation of iodide and bromide derivatives. Switching to the non-innocent bis-iminopyridine ligands promotes a previously undescribed Csp2−H activation reaction leading to biaryl derivatives. First clues into the intricate nature of the mechanism were obtained and suggested that the redox-active bis-iminopyridine ligand acts as an electron reservoir. The resulting buildup of electron density triggers the C−H bond breaking. All these findings are discussed in light of the existing literature and perspectives are given. 相似文献