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51.
Carolina Simó Clara Ibá?ez Alberto Valdés Alejandro Cifuentes Virginia García-Ca?as 《International journal of molecular sciences》2014,15(10):18941-18966
Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs) making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not) the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade. 相似文献
52.
Xin Zhang Janet L. Huebner Virginia Byers Kraus 《International journal of molecular sciences》2021,22(15)
Along with cytokines, extracellular vesicles (EVs) released by immune cells in the joint contribute to osteoarthritis (OA) pathogenesis. By high-resolution flow cytometry, we characterized 18 surface markers and 4 proinflammatory cytokines carried by EVs of various sizes in plasma and synovial fluid (SF) from individuals with knee OA, with a primary focus on immune cells that play a major role in OA pathogenesis. By multiplex immunoassay, we also measured concentrations of cytokines within (endo) and outside (exo) EVs. EVs carrying HLA-DR, -DP and -DQ were the most enriched subpopulations in SF relative to plasma (25–50-fold higher depending on size), suggesting a major contribution to the SF EV pool from infiltrating immune cells in OA joints. In contrast, the CD34+ medium and small EVs, reflecting hematopoietic stem cells, progenitor cells, and endothelial cells, were the most significantly enriched subpopulations in plasma relative to SF (7.3- and 7.7-fold higher). Ratios of EVs derived from neutrophils and lymphocytes were highly correlated between SF and plasma, indicating that plasma EVs could reflect OA severity and serve as systemic biomarkers of OA joint pathogenesis. Select subsets of plasma EVs might also provide next generation autologous biological products for intra-articular therapy of OA joints. 相似文献
53.
Maria Virginia Gelfuso Juan Oswaldo Montoya Uribe Daniel Thomazini 《International Journal of Applied Ceramic Technology》2019,16(2):868-882
The influence of the CuO–TiO2 phase (CT) on dielectric properties of the CCTO ceramic was investigated. CaCuXTiYO12 (CCXTYO) powders were prepared based on the coprecipitated method, where 2.70 ≤ x ≤ 3.30 and 3.25 ≤ y ≤ 4.75. XRD patterns confirmed the presence of CCTO and also the secondary phases as CuO, TiO2, and CaTiO3 for each sample and aided in its quantification. Scanning Electron Microscopy (SEM) shows secondary phases evolution in the grain boundaries, and its influence on size and morphology of the grains. Impedance spectroscopy measurements showed that the ceramics with lower amount of CuO and TiO2 phases (CT/deficient ceramics) exhibited the highest ε′ values (2.1 × 104 at 1 kHz for CC2.9T3.75O ceramic). Also, CT/deficient ceramics showed lower tanδ values (0.090 at 1 kHz for CC2.9T3.75O ceramic) than ceramics prepared with excessive CuO–TiO2 phase (0.241 at 1 kHz for CC3.1T4.25O ceramics). The deficiency of CuO and TiO2 phases associated with high percentage of CCTO and CaTiO3 phases resulted in ceramics with the higher ε′ values. 相似文献
54.
Ester Rojo M. Virginia Alonso Beln Del Saz‐Orozco Mercedes Oliet Francisco Rodriguez 《应用聚合物科学杂志》2015,132(26)
Viscose cellulosic fibers from eucalyptus wood were treated with organosilanes to introduce specific functionalities on the fibers and enhance their wettability and adhesion with phenolic matrices in composites. Modeling procedures were employed to optimize the conditions of the treatments of the fibers with the silanes (3‐aminopropyl) trimethoxysilane (APS) and 3‐(2‐aminoethylamino) propyltrimethoxysilane (AAPS). The analyzed responses were relative intensities of the bands 1565/897 and 1120/897 cm−1, measured by Fourier transform infrared spectroscopy, and the silicon amount incorporated into the cellulosic fibers, which was determined by energy dispersive X‐ray analysis. In addition, surface morphology of the silane treated fibers was observed using scanning electron microscopy. The treatments of the cellulosic fibers with 2.2% APS for 120 min and 1.5% AAPS for 100 min were selected as optimums. According to contact angle measurements, both treatments enhanced the wettability between the fibers and a resol‐type phenolic resin, revealing the possible use of the silane treated fibers as reinforcement in phenolic composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42157. 相似文献
55.
Age-normed tests of listening comprehension, oral expression, reading comprehension, and written expression were administered in Grades 1 (n = 128), 3, and 5, or 3 (n = 113), 5, and 7. Confirmatory factor analyses compared 1- and 4-factor models at each grade level and supported a 4-factor model of language by ear, mouth, eye, and hand. Multiple regressions identified which of the 3 other language skills explained unique variance in each of the 4 language skill outcomes and provided additional evidence that language is not a single skill. Individuals' ipsative scores (amount that the standard score for age on each language measure deviated from individual's mean for all 4 measures) showed that 25% to 30% of individuals showed relative strengths or weaknesses (±1 SD) in specific language skills, but only 7% were stable across Grades 3 and 5. Findings are discussed in reference to (a) theoretical implications for idea comprehension and expression via language by ear, mouth, eye, and hand; and (b) educational applications of observed developmental and individual differences for general, special, and gifted education. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Federico Peinado Virginia Francisco Raquel Hervás Pablo Gervás 《Minds and Machines》2010,20(4):565-588
Novelty is a key concept to understand creativity. Evaluating a piece of artwork or other creation in terms of novelty requires comparisons to other works and considerations about the elements that have been reused in the creative process. Human beings perform this analysis intuitively, but in order to simulate it using computers, the objects to be compared and the similarity metrics to be used should be formalized and explicitly implemented. In this paper we present a study on relevant elements for the assessment of novelty in computer-generated narratives. We focus on the domain of folk-tales, working with simple plots and basic narrative elements: events, characters, props and scenarios. Based on the empirical results of this study we propose a set of computational metrics for the automatic assessment of novelty. Although oriented to the implementation of our own story generation system, the measurement methodology we propose can be easily generalized to other creative systems. 相似文献
57.
58.
Artificial Intelligence (AI) is the science of building computer devices and software applications that mimic many of the characteristics that we associate with human behaviour, such as the ability to reason, see, learn, solve problems, understand languages, and so on. AI systems include natural languages, robotics, expert systems and neural networks. This article focuses on neural networks, which can be designed for problems that arise at any managerial level and may be used to predict the occurrence of fraud. 相似文献
59.
Estimation of evaporative fraction and evapotranspiration from MODIS products using a complementary based model 总被引:5,自引:0,他引:5
We present a new formulation to derive evaporative fraction (EF) and evapotranspiration (ET) maps from remotely sensed data without auxiliary relationships or site-specific relationships. This formulation is based on Granger's complementary relationship and Priestley-Taylor's equation. The proposed model eliminates the wind function and resistance parameters commonly applied to ET calculation by including a relative evaporation parameter (ET/Epot). By combining this relative evaporation parameter, Granger's complementary relationship and Priestley-Taylor equation, we obtain a simple equation to estimate ET. We tested and validated the proposed formulation over the Southern Great Plains (SGP) region of the United States for seven clear sky days during March-October 2003. MODIS Atmospheric and Land products were the only source of data used in this study. Estimates of ET show an overall root mean square error and bias of 33.89 and − 10.96 Wm− 2, respectively. Our results suggest that the proposed approach is robust and valid for a wide range of atmospheric and surface conditions. 相似文献
60.
Virginia Hamilton Youling Yuan Debbie A Rigney Betsy M Chesnutt Aaron D Puckett Joo L Ong Yunzhi Yang Warren O Haggard Steven H Elder Joel D Bumgardner 《Polymer International》2007,56(5):641-647
Chitosan has been widely researched for bone tissue and implant applications. While initial results are promising, there are inconsistent reports regarding the biological responses. This may be due to inadequate evaluation of chitosan material properties. This study evaluated normal human osteoblast precursor cell attachment and proliferation on a series of well‐characterized chitosan films. The chitosan films exhibited a range of properties: 76–96% degree of de‐acetylation (DDA), 2400–8200 kDa viscosity‐average molecular weight, 62–90° contact angle, 0.24–2.46% residual ash, 5.3–287 µg cm?2 residual protein and 23–40% crystallinity. There was no trend or correlation between DDA, crystallinity, contact angle, molecular weight, residual ash or protein content and the attachment or growth of bone cells on chitosan films. All films supported higher levels of bone cell proliferation than tissue culture plastic, which supports the general hypothesis that chitosans are osteocompatible. The 78 and 92% DDA chitosan films supported the most cell proliferation, approximately 16 times that of tissue culture plastic controls, but no chitosan physiochemical property correlated with the increased cell growth. The lack of correlation is hindered since more than one physiochemical property changed for each chitosan material. Data do indicate that there may be much variability in chitosan materials, and this variability may make understanding and comparing biological performance of chitosan materials difficult. These results highlight the need for systematic characterizations of chitosan materials for predictable biomedical applications. Copyright © 2006 Society of Chemical Industry 相似文献