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151.
The aim of this work was to identify the main sources of uncertainty, quantify the standard deviation of each source of uncertainty, and calculated combined and expended uncertainties for the determination of linezolid in injectable dosage forms by UV spectrophotometry. The contributions of precision, linearity and weight of linezolid reference standard are the most significant, contributing with about 77% of the overall uncertainty. The uncertainties on the absorbances (sample and standard), volumetric flasks and volumetric pipettes have virtually no influence on the overall uncertainty. The estimated uncertainty of the spectrophotometric method for determination of linezolid was adequate for the scope of the method. 相似文献
152.
Major Brenda; Appelbaum Mark; Beckman Linda; Dutton Mary Ann; Russo Nancy Felipe; West Carolyn 《Canadian Metallurgical Quarterly》2009,64(9):863
The authors evaluated empirical research addressing the relationship between induced abortion and women’s mental health. Two issues were addressed: (a) the relative risks associated with abortion compared with the risks associated with its alternatives and (b) sources of variability in women’s responses following abortion. This article reflects and updates the report of the American Psychological Association Task Force on Mental Health and Abortion (2008). Major methodological problems pervaded most of the research reviewed. The most rigorous studies indicated that within the United States, the relative risk of mental health problems among adult women who have a single, legal, first-trimester abortion of an unwanted pregnancy is no greater than the risk among women who deliver an unwanted pregnancy. Evidence did not support the claim that observed associations between abortion and mental health problems are caused by abortion per se as opposed to other preexisting and co-occurring risk factors. Most adult women who terminate a pregnancy do not experience mental health problems. Some women do, however. It is important that women’s varied experiences of abortion be recognized, validated, and understood. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
153.
Felix A. Reifler Felipe A.L. Sánchez Frank J. Clemens Ksenija Varga Rudolf Hufenus 《Composites Science and Technology》2010
A concept for the realisation of composite layers on the surface of synthetic fibres by continuous liquid film coating of spread roving or monofilaments with a slurry containing ceramic particles and a polymeric binder is successfully demonstrated. Polyamide 6 monofilaments were coated with alumina particles and a polyurethane elastomer based binder system to achieve higher abrasion resistance. Under frictional load, the coating is abraded in small units consisting of some particles and the surrounding polyurethane matrix, which predetermines it to be used as sacrificial layer. The slurries showed shear thinning behaviour. Increasing the content of the rheological agent (carboxymethylcellulose [CMC]) led to an exponential increase of the viscosity, which therefore can be tailored by varying the CMC content. An increase of fibre radius, slurry viscosity or withdrawal speed led to an increase of the coating thickness, which is in accordance to published results of Newtonian or non-Newtonian coating fluids. 相似文献
154.
Felipe Correa 《Architectural Design》2007,77(2):98-105
Underfoot, obscured from view, ground is the most fundamental material of construction and the urban landscape. As New Orleans has proved, we forget it at our peril. Shaped by the mound, the levee and most recently the pump, the ground of the Crescent City was neglected and overlooked even in areas of new development. Felipe Correa describes how, in the aftermath of Hurricane Katrina, the thorough re-evaluation of the city's ground is a prerequisite to urban reorganisation. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
155.
156.
Felipe Espinosa Elena López Raúl Mateos Manuel Mazo Ricardo García 《Autonomous Robots》2001,11(2):137-148
This paper presents the theoretical support and experimental results of the application of advanced and intelligent control techniques to the drive control and trajectory tracking systems on a robotic wheelchair. The adaptive optimal control of the differential drive helps to improve the automatic guidance system's safety and comfort taking into consideration operating conditions such as load and distribution changes or motion actuator limitations. Furthermore, the incorporation of an optimal controller to minimize location errors and a fuzzy controller to adapt the linear velocity to the characteristics of the trajectory, provide the vehicle with a high degree of intelligence and autonomy, even when faced with obstacles. The global control solution implemented increases the features of the wheelchair for handicapped people, especially for those with a high degree of disability. 相似文献
157.
Camila Reyes Estefanía Nova-Lamperti Daniel Duran-Sandoval Daniela Rojas Jorge Gajardo Enrique Guzman-Gutierrez Camila Bustos-Ruiz Valeska Ormazbal Felipe A. Zúiga Carlos Escudero Claudio Aguayo 《International journal of molecular sciences》2022,23(13)
Oxidized low-density lipoprotein (ox-LDL) is the most harmful form of cholesterol associated with vascular atherosclerosis and hepatic injury, mainly due to inflammatory cell infiltration and subsequent severe tissue injury. Lox-1 is the central ox-LDL receptor expressed in endothelial and immune cells, its activation regulating inflammatory cytokines and chemotactic factor secretion. Recently, a Lox-1 truncated protein isoform lacking the ox-LDL binding domain named LOXIN has been described. We have previously shown that LOXIN overexpression blocked Lox-1-mediated ox-LDL internalization in human endothelial progenitor cells in vitro. However, the functional role of LOXIN in targeting inflammation or tissue injury in vivo remains unknown. In this study, we investigate whether LOXIN modulated the expression of Lox-1 and reduced the inflammatory response in a high-fat-diet mice model. Results indicate that human LOXIN blocks Lox-1 mediated uptake of ox-LDL in H4-II-E-C3 cells. Furthermore, in vivo experiments showed that overexpression of LOXIN reduced both fatty streak lesions in the aorta and inflammation and fibrosis in the liver. These findings were associated with the down-regulation of Lox-1 in endothelial cells. Then, LOXIN prevents hepatic and aortic tissue damage in vivo associated with reduced Lox-1 expression in endothelial cells. We encourage future research to understand better the underlying molecular mechanisms and potential therapeutic use of LOXIN. 相似文献
158.
Pablo Sendín‐Raña Francisco J. González‐Castaño Enrique Pérez‐Barros Pedro S. Rodríguez‐Hernández Felipe Gil‐Castiñeira José M. Pousada‐Carballo 《Software》2009,39(3):279-298
For a long time, the design of relational databases has focused on the optimization of atomic transactions (insert, select, update or delete). Currently, relational databases store tactical information of data warehouses, mainly for select‐like operations. However, the database paradigm has evolved, and nowadays on‐line analytical processing (OLAP) systems handle strategic information for further analysis. These systems enable fast, interactive and consistent information analysis of data warehouses, including shared calculations and allocations. OLAP and data warehouses jointly allow multidimensional data views, turning raw data into knowledge. OLAP allows ‘slice and dice’ navigation and a top‐down perspective of data hierarchies. In this paper, we describe our experience in the migration from a large relational database management system to an OLAP system on top of a relational layer (the data warehouse), and the resulting contributions in open‐source ROLAP optimization. Existing open‐source ROLAP technologies rely on summarized tables with materialized aggregate views to improve system performance (in terms of response time). The design and maintenance of those tables are cumbersome. Instead, we intensively exploit cache memory, where key data reside, yielding low response times. A cold start process brings summarized data from the relational database to cache memory, subsequently reducing the response time. We ensure concurrent access to the summarized data, as well as consistency when the relational database updates data. We also improve the OLAP functionality, by providing new features for automating the creation of calculated members. This makes it possible to define new measures on the fly using virtual dimensions, without re‐designing the multidimensional cube. We have chosen the XML/A de facto standard for service provision. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
159.
160.
Sara de Souza Comapa Luciedry Matheus Souza Carvalho Carlos Victor Lamarão Francisca das Chagas do Amaral Souza Jaime Paiva Lopes Aguiar Laiane Souza da Silva Josiana Moreira Mar Edgar Aparecido Sanches Felipe Faccini dos Santos Jaqueline de Araújo Bezerra Pedro Henrique Campelo 《Journal of Food Processing and Preservation》2019,43(7):e13989