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991.
Ribeiro Vieira P de Faria E de Faria F Sperandio N Araújo C Stofeles R Alves D Castro Sdo C Bressan J Eloiza S 《Archivos latinoamericanos de nutrición》2011,61(3):279-287
Factors associated with adiposity in normal weight female adolescents with adequate and high percent body fat: elaborating a risk model. This study was carried out to evaluate the factors associated with adiposity in normal weight adolescents presenting appropriate or high percent body fat, who attended the public schools in Vi?osa county-Minas Gerais/Brazil. A total of 118 female adolescents at age range from 14 to 19 years and have already presented the menarche were evaluated. The adolescents were divided into 2 groups: G1 with high percent body fat and G2 with appropriate percent body fat. The following variables were evaluated: anthropometric, body composition, lifestyle and the family history of non-communicable chronic diseases. In subsample, the basal energy consumption was determined by indirect calorimetry. The G1-grouped adolescents showed higher values for most anthropometric and body composition variables (p < 0.001). No differences were observed (p > 0.05) for basal metabolism and metabolism of lean body mass, smoking habit, total energy consumption and protein and lipid as well between groups. When comparing the physical activity level, the G1 adolescents spent more time with 1-level sedentary activities whereas the G2 ones showed higher total caloric consumption with daily activities (p < 0.001). According to risk factors under analysis, the variables related to lifestyle, as distinguishing the use of sweeteners (OR = 13.47), provided higher contribution to excessive adiposity in the normal weight adolescents. The detailed analysis of the body composition as well as the risk factors associated with excessive body fat makes possible the early diagnosis and the development of more appropriate intervention means. 相似文献
992.
Daniela Stoica Paul J. Brewer Richard J.C. Brown Paola Fisicaro 《Electrochimica acta》2011,(27):10009
The influence of several parameters in the preparation procedure of thermal–electrolytic Ag/AgCl electrodes on the resulting electrode performance has been studied. In particular, we report the effect on electrode performance of subtle variations in the preparation of silver oxide paste used for electrode manufacture, in thermal annealing conditions employed and in the procedure for electrochemically converting a fraction of the electrode from silver to silver chloride. Scanning electron microscopy and electrochemical impedance spectroscopy have been used to study the characteristics of the electrodes produced. This work reveals a correlation between the electrochemical behaviour and surface physical characteristics – in particular electrode porosity. The outputs of this study have positive implications for improving the accuracy and comparability of primary pH measurement. 相似文献
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994.
In this paper, the web crippling strength of cold-formed steel plain channel beams subjected to concentrated loads is evaluated on the basis of numerical models and available test results. The design equations existing in current steel codes display many coefficients, have not theoretical background and overlook the slenderness concept, which is a trademark of safety checking rules related with other failure modes such as column flexural-torsional buckling, web shear buckling and plate buckling. The main objective is to show that such slenderness-based approach is possible for web crippling design. Firstly, some considerations about the web crippling of cold-formed steel beams are drawn and a brief review is made. Secondly, the equations for web crippling design available in current Eurocode 3 and AISI steel codes are described. Then, the numerical model is explained in detail. On the basis of numerical and experimental results, it is shown that an approach based on the slenderness concept leads to fairly good estimates of web crippling load. Finally, some conclusions are drawn. 相似文献
995.
Second‐order statistics of system with N‐branch microdiversity and L‐branch macrodiversity operating over gamma shadowed Nakagami‐m fading channels
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Nikola M. Sekulović Mihajlo Č. Stefanović Daniela M. Milović Selena Ž. Stanojčić 《International Journal of Communication Systems》2014,27(2):390-400
The problem concerning short‐term fading and long‐term fading (shadowing) and their deleterious effects on wireless systems performance has been in focus for a long time. In this paper, motivated by the results of propagation measurements in land‐mobile and indoor‐mobile systems, and by the fact that gamma distribution can describe shadowing reliably, Nakagami‐m distribution is used to model the signal envelope and gamma distribution is used to model the average signal power. Receive diversity with maximal‐ratio combining and selection combining is implemented at the microlevel and macrolevel, respectively. The general case is explored, which assumes that microdiversity and macrodiversity are provided through arbitrary number of channels. Because shadowing has larger correlation distance than short‐term fading, correlated macrodiversity channels are studied. This paper investigates the dynamics of the received signal. A novel rapidly converging infinite‐series expression for average level crossing rate and average fade duration are obtained. Numerical results are graphically presented to examine the impact of fading severity, shadowing severity, number of diversity branches at the microlevel, number of base stations and correlation between base stations to the system's performance. Computer simulations are also performed to verify the validity and the accuracy of proposed theoretical analysis. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
996.
Lorenza Pastorino Bruna Dalmasso Eleonora Allavena Irene Vanni Filippo Ugolini Gianna Baroni Michela Croce Antonio Guadagno Francesco Cabiddu Virginia Andreotti William Bruno Gabriele Zoppoli Lorenzo Ferrando Enrica Teresa Tanda Francesco Spagnolo Chiara Menin Rosaria Gangemi Daniela Massi Paola Ghiorzo 《International journal of molecular sciences》2022,23(24)
ATM germline pathogenic variants were recently found enriched in high-risk melanoma patients. However, ATM loss of heterozygosity (LOH) has never been investigated in melanoma and, therefore, a causal association with melanoma development has not been established yet. The purpose of this study was to functionally characterize 13 germline ATM variants found in high-risk melanoma patients—and classified by in silico tools as pathogenic, uncertain significance, or benign—using multiple assays evaluating ATM/pATM expression and/or LOH in melanoma tissues and cell lines. We assessed ATM status by Immunohistochemistry (IHC), Western Blot, Whole-Exome Sequencing/Copy Number Variation analysis, and RNA sequencing, supported by Sanger sequencing and microsatellite analyses. For most variants, IHC results matched those obtained with in silico classification and LOH analysis. Two pathogenic variants (p.Ser1135_Lys1192del and p.Ser1993ArgfsTer23) showed LOH and complete loss of ATM activation in melanoma. Two variants of unknown significance (p.Asn358Ile and p.Asn796His) showed reduced expression and LOH, suggestive of a deleterious effect. This study, showing a classic two-hit scenario in a well-known tumor suppressor gene, supports the inclusion of melanoma in the ATM-related cancer spectrum. 相似文献
997.
Federico Zappaterra Chiara Tupini Daniela Summa Virginia Cristofori Stefania Costa Claudio Trapella Ilaria Lampronti Elena Tamburini 《International journal of molecular sciences》2022,23(4)
Biocatalyzed synthesis can be exploited to produce high-value products, such as prodrugs. The replacement of chemical approaches with biocatalytic processes is advantageous in terms of environmental prevention, embracing the principles of green chemistry. In this work, we propose the covalent attachment of xylitol to ibuprofen to produce an IBU-xylitol ester prodrug. Xylitol was chosen as a hydrophilizer for the final prodrug, enhancing the water solubility of ibuprofen. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) extensively used as an analgesic, anti-inflammatory, and antipyretic. Despite being the third-most-prescribed medicine in the world, the aqueous solubility of ibuprofen is just 21 mg/L. This poor water solubility greatly limits the bioavailability of ibuprofen. We aimed to functionalize ibuprofen with xylitol using the reusable immobilized N435 biocatalyst. Instead of a biphasic media, we proposed a monophasic reaction environment. The characterization of the IBU-xylitol ester was performed by 1H, 13C-NMR, DEPT, COSY, HMQC, HMBC, FTIR, and MS spectroscopy. Preliminary in vitro tests showed that this enzymatically synthesized prodrug of ibuprofen reduced the expression of the interleukin 8 genes in human bronchial epithelial cells (IB3-1) from cystic fibrosis (CF) patients. 相似文献
998.
999.
1000.
Daniela Passarella Maurizio Ronci Valentina Di Liberto Mariachiara Zuccarini Giuseppa Mud Carola Porcile Monica Frinchi Patrizia Di Iorio Henning Ulrich Claudio Russo 《International journal of molecular sciences》2022,23(15)
Recent studies have highlighted the mechanisms controlling the formation of cerebral cholesterol, which is synthesized in situ primarily by astrocytes, where it is loaded onto apolipoproteins and delivered to neurons and oligodendrocytes through interactions with specific lipoprotein receptors. The “cholesterol shuttle” is influenced by numerous proteins or carbohydrates, which mainly modulate the lipoprotein receptor activity, function and signaling. These molecules, provided with enzymatic/proteolytic activity leading to the formation of peptide fragments of different sizes and specific sequences, could be also responsible for machinery malfunctions, which are associated with neurological, neurodegenerative and neurodevelopmental disorders. In this context, we have pointed out that purines, ancestral molecules acting as signal molecules and neuromodulators at the central nervous system, can influence the homeostatic machinery of the cerebral cholesterol turnover and vice versa. Evidence gathered so far indicates that purine receptors, mainly the subtypes P2Y2, P2X7 and A2A, are involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s and Niemann–Pick C diseases, by controlling the brain cholesterol homeostasis; in addition, alterations in cholesterol turnover can hinder the purine receptor function. Although the precise mechanisms of these interactions are currently poorly understood, the results here collected on cholesterol–purine reciprocal control could hopefully promote further research. 相似文献