2,666 research outputs found

    Adsorption of proteins to thin-films of PDMS and its effect on the adhesion of human endothelial cells

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    This paper describes a simple and inexpensive procedure to produce thin-films of poly(dimethylsiloxane). Such films were characterized by a variety of techniques (ellipsometry, nuclear magnetic resonance, atomic force microscopy, and goniometry) and used to investigate the adsorption kinetics of three model proteins (fibrinogen, collagen type-I, and bovine serum albumin) under different conditions. The information collected from the protein adsorption studies was then used to investigate the adhesion of human dermal microvascular endothelial cells. The results of these studies suggest that these films can be used to model the surface properties of microdevices fabricated with commercial PDMS. Moreover, the paper provides guidelines to efficiently attach cells in BioMEMS devices.Fil: Chumbimuni Torres, Karin Y.. The University of Texas at San Antonio; Estados UnidosFil: Coronado, Ramon E.. The University of Texas at San Antonio; Estados UnidosFil: Mfuh, Adelphe M.. The University of Texas at San Antonio; Estados UnidosFil: Castro Guerrero, Carlos. The University of Texas at San Antonio; Estados UnidosFil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Negrete, George R.. The University of Texas at San Antonio; Estados UnidosFil: Bizios, Rena. The University of Texas at San Antonio; Estados UnidosFil: Garcia, Carlos D.. The University of Texas at San Antonio; Estados Unido

    Structural studies of two Tinuvin® P analogs: 2-(2,4-Dimethylphenyl)- 2H-benzotriazole and 2-phenyl-2H-benzotriazole

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    2-(2,4-Dimethylphenyl)-2H-benzotriazole (1) has been synthesized in a three step procedure starting from 2,4-dimethyl-N-(2-nitrophenyl)benzamide via a 5-(2,4-dimethylphenyl)-1-(2-nitrophenyl)-1H-tetrazole intermediate. Its structure and those of Tinuvin® P and 2-phenyl-2H-benzotriazole (5) have been studied by multinuclear NMR (1H-, 13C- and 15N-) in solution and in the solid state. X-ray diffraction analysis of 1 and 5 allowed to us establish the molecular conformation around the single bond connecting the two aromatic systems, in agreement with the conclusions drawn from the NMR study. In the case of 1 ab initio geometry optimization was achieved at the Hartree-Fock HF/6-31G** and DFT B3LYP/6-31G ** levels. © 2007 by MDPI.Peer Reviewe

    Current paradigms in intelligent transportation systems

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    Intelligent transportation systems (ITS) constitute today a multidisciplinary field of study involving a large number of different research areas. As a consequence, it is difficult to achieve a structured view of ITS, which is necessary to unify efforts and as guidance for future developments. This study aims to identify the main paradigms in the field of ITS by semantically analysing studies related to this general topic. An understanding about which research is considered valuable by the research community to build upon may provide valuable insights in this field. As a result of the statistical treatment of data, up to 13 paradigms are obtained. The scope of these paradigms and the relationships between them have also been detailed, providing a structured vision of ITS synthesised in a map formMinisterio de Educación y Ciencia DPI2007- 60128Junta de Andalucía. Consejería de Innovación, Ciencia y Empresa P07-TIC-0262

    An approach to identify solutions of interest from multi and many-objective optimization problems

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    The result of a multiobjective or a many-objective optimization problem is a large set of non-dominated solutions. Once the Pareto Front (or a good approximation of it) has been found, then providing the decision maker with a smaller set of “interesting solutions” is a key step. Here, the focus is on how to select such a set of solutions of interest which, in contrast to previous approaches that relied on geometrical features, is carried out considering the decision maker’s preferences. The proposed a posteriori approach consists in assigning an interval of potential scores to every solution, where such scores depend on the decision maker’s preferences. The solutions are then compared and filtered according to their corresponding intervals, using a recently proposed possibility degree formula. Three examples, with two, three and many objectives are used to show the benefits of the proposal.D. A. Pelta and M. T. Lamata acknowledge support through Project TIN2017-86647-P from the Spanish Ministry of Economy and Competitiveness (including European Regional Development Funds). M. Torres enjoys a Ph.D. research training staff grant associated with the Project TIN2014-55024-P from the Spanish Ministry of Economy and Competitiveness and co-funded by the European Social Fund. R. Yager acknowledges the support of the United States Office of Naval Research (ONR)

    A cross-country review on energy efficiency drivers

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    Energy efficiency remains as the main mitigation factor to slow down the growth of energy consumption and related CO2 emissions, undoubtedly the major responsible for climate change. Gaining insights into the driving forces that make efficiency change is a keystone to define energy policies and examine pathways to sustainable development. To this aim, this paper proposes a pyramidal approach for the analysis and decomposition of energy intensity, the main global efficiency indicator, using the LMDI method. First, the effects related to supply and demand sides of the energy system are separated in Primary Energy Factor and final energy intensity, respectively. Then, supply side is further decomposed to progressively reveal structural effects associated to transformation processes and fuel types. The approach is applied to the most emitting and consuming nations (China, United States, European Union, India, Russia, Japan) to provide a meaningful cross-country analysis over the period 1995–2017. Results show that energy intensity gains have been mainly driven by widespread demand side efficiency improvements from 25% to 61%. Regarding the supply side, unfavourable structural changes due to electrification, up to 12% in China, have only been offset by transformation efficiency gains about 6% in developed countries. Consequently, emerging economies have worsened their energy sector efficiency as they thrive. Changes in fuel mixes have generally contributed to energy intensity reductions (up to 4%) mainly due to shifts from coal and nuclear power towards gas and renewables plants. The proposed methodology could help stakeholders to effectively analyse the energy system and to develop policies to reduce its environmental impact

    Health Through a Human Right Lens at the US-Mexico Border: Increasing Access to Healthcare for Central American Immigrants

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    The number of immigrants seeking entry into the U.S. through asylum requests or through irregular means is increasing, and most come from the Northern Triangle of El Salvador, Guatemala, and Honduras. Immigrants come fleeing extreme poverty, violence, health and social inequities, and drastic climate changes. Most had limited access to healthcare at home, and even more limited care along the journey. Those that are allowed entry into the U.S., are confronted with feeling unwelcome in many communities, having to navigate an array of local, state, and federal laws that regulate access to healthcare. We need immigration policies that preserve the health, dignity with a multinational policy for provision of healthcare through a human rights lens from point of origin to point of destination

    A Study on the Phytotoxic Potential of the Seasoning Herb Marjoram (Origanum majorana L.) Leaves

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    In the search of new alternatives for weed control, spices appear as an option with great potential. They are rich in bioactive natural products and edible, which might minimize toxicity hazard. Marjoram (Origanum majorana L.) is an aromatic herb that has been widely employed as a seasoning herb in Mediterranean countries. Although marjoram boasts a plethora of therapeutic properties (painkiller, antibiotic, treatment for intestinal disorders, etc.), the potential for its extracts for weed control is still to be more thoroughly explored. In order to determine their phytotoxic potential, marjoram leaves were subjected to different bioguided extraction processes, using water, ethyl acetate, acetone or methanol. The most active extract (acetone) was sequentially fractionated to identify its most active compounds. This fractionation led to the isolation and identification of 25 compounds that were classified as monoterpenes, diterpenes or flavonoids. Among them, a new compound named majoradiol and several compounds are described in marjoram for the first time. The phytotoxicity of the major compounds to etiolated wheat coleoptiles was compared against that of the commercial herbicide (Logran(R)), with similar or higher activity in some cases. These results confirm the extraordinary potential of the extracts from this edible plant to develop safer and more environmentally friendly herbicides

    NDT-Driver: A Java Tool to Support QVT Transformations for NDT

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    Ministerio de Ciencia e Innovación TIN2010-20057-C03-02Ministerio de Ciencia e Innovación TIN2010-12312-EMinisterio de Educación y Ciencia TIN2007-67843-C06-0

    Nosocomial outbreak of Pseudomonas aeruginosa endophthalmitis

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    We describe an outbreak of nosocomial endophthalmitis due to a common source, which was determined to be trypan blue solution prepared in the hospital's pharmacy service. We assume that viable bacteria probably gained access to the trypan blue stock solution during cooling after autoclaving. The temporal cluster of Pseudomonas aeruginosa endophthalmitis was readily perceived on the basis of clinical and microbiological findings, and an exogenous source of contamination was unequivocally identified by means of DNA fingerprinting. © 2006 by The Society for Healthcare Epidemiology of America. All rights reserved
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