25 research outputs found

    Multiwavelength study of the starburst galaxy NGC7714. I: Ultraviolet-Optical spectroscopy

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    We have studied the physical conditions in the central 300 pc of the proto-typical starburst galaxy NGC 7714. Our analysis is based on ultraviolet spectroscopy with the HST+GHRS and ground-based optical observations.The data are interpreted using evolutionary models optimized for young starburst regions. The massive stellar population is derived in a self-consistent way using the continuum and stellar absorption lines in the ultraviolet and the nebular emission line optical spectrum. The central starburst has an age of about 4.5 Myr, with little evidence for an age spread. Wolf-Rayet features at the ultraviolet indicates a stellar population of \sim 2000 Wolf-Rayet stars. The overall properties of the newly formed stars are quite similar to those derived, e.g., in 30 Doradus. A standard Salpeter IMF is consistent with all observational constraints. We find evidence for spatial structure within the central 300 pc sampled. Therefore it is unlikely that the nucleus of NGC 7714 hosts a single star cluster exceeding the properties of other known clusters. Contrary to previous suggestions, we find no evidence for a nuclear supernova rate that would significantly exceed the total disk-integrated rate. About one supernova event per century is predicted.Comment: 19 pages, 9 figures in a tar file. Accepted for publication in ApJ, 1999, March, issue 51

    Hypoxic pulmonary vasoconstriction, carotid body function and erythropoietin production in adult rats perinatally exposed to hyperoxia

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    Adult mammalians possess three cell systems that are activated by acute bodily hypoxia: pulmonary artery smooth muscle cells (PASMC), carotid body chemoreceptor cells (CBCC) and erythropoietin (EPO)-producing cells. In rats, chronic perinatal hyperoxia causes permanent carotid body (CB) atrophy and functional alterations of surviving CBCC. There are no studies on PASMC or EPO-producing cells. Our aim is to define possible long-lasting functional changes in PASMC or EPO-producing cells (measured as EPO plasma levels) and, further, to analyse CBCC functional alterations. We used 3- to 4-month-old rats born and reared in a normal atmosphere or exposed to perinatal hyperoxia (55–60% O2 for the last 5–6 days of pregnancy and 4 weeks after birth). Perinatal hyperoxia causes an almost complete loss of hypoxic pulmonary vasoconstriction (HPV), which was correlated with lung oxidative status in early postnatal life and prevented by antioxidant supplementation in the diet. O2-sensitivity of K+ currents in the PASMC of hyperoxic animals is normal, indicating that their inhibition is not sufficient to trigger HPV. Perinatal hyperoxia also abrogated responses elicited by hypoxia on catecholamine and cAMP metabolism in the CB. An increase in EPO plasma levels elicited by hypoxia was identical in hyperoxic and control animals, implying a normal functioning of EPO-producing cells. The loss of HPV observed in adult rats and caused by perinatal hyperoxia, comparable to oxygen therapy in premature infants, might represent a previously unrecognized complication of such a medical intervention capable of aggravating medical conditions such as regional pneumonias, atelectases or general anaesthesia in adult life.This work was supported by Grants BFU2012-37459 from the Ministry of Economy and Competitiveness (Spain) and Grant CIBER CB06/06/0050 from the Institute of Health Carlos III (Spain) to C. G. Also supported by Grants SAF2011-28150 to F.P-V and SAF2010-22066-C02-02 to AC from the Ministry of Economy and Competitiveness (Spain).Peer Reviewe

    Equality, Equity, and Diversity: Educational Solutions in the Basque Country

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    Public education is one of the greatest achievements of European countries during the twentieth century. While schooling systems neither exclusively form citizens, nor are they sufficient to alleviate all inequalities, education plays an increasingly important strategic role in relieving social problems and promoting the civic and ethical upbringing of our children. Researchers and professors at the UPV/EHU have had the privilege to design and implement important educational projects in conjunction with government of Autonomous Community of the Basque Country, which has the authority over education in its territory. This book presents the timely (in most cases since 2000) observations, research, and programs that have resulted from this cooperation. Our stress—in both our theoretical and analytical dimensions—has been on the importance of diversity, the promotion of social and human values, and respect for basic human rights. In addition, we describe the cooperation that must be fostered—and the various needs met—between all educational "agents": academic researchers, administrators, teachers, parents, and the community at large to promote equality and fairness in our society.This book was published with generous financial support from the Basque Government.Introduction: Alfonso Unceta and Concepción Medrano ? Part 1 Education in the Basque Country ? 1. Education Provision in the Basque Country by Alfonso Unceta and Andrés Davila ? 2. Addressing Basque Diversity in the Classroom: Measures to Avoid Excluding At-Risk Youth by Begoña Martínez Domínguez ? 3. Improving Social Interaction: Experimentally Validated Proposals for Psycho-educational Intervention by Maite Garaigodobil and Jone Aliri ? 4. Socialization to Prevent Gender Violence in the Basque Country by Maria José Alonso Olea, Aitor Gómez González, and Nekane Beloki Arizti ? 5. Resolution and Transformation of At-School Conflicts by Ramón Alzate Sáez de Heredia, Lucía Gorbeña, and Cristina Merino ? Part 2 Socioeducational Context in the Basque Country ? 6. Learning Communities: A Basque Egalitarian Educational Project by Maite Arandia Loroño, Isabel Martínez Domínguez, and Iñaki Santa Cruz Ayo ? 7. Migrants en Route: Community Socioeducational Action by Miguel Arriaga Landeta and Begoña Abad Miguélez ? 8. Educating from the Family: A Proposal to Connect Homes and Institutions by Enrique Arranz Freijo, Fernando Olabarrieta Artetxe, Juan Luis Martín Ayala ? 9. The Development of Values and the Media by Concepción Medrano, Ana Aierbe, and Juan Ignacio Martínez de Morentin ? Index ? List of Contributor

    Utility of a thematic network in primary health care: a controlled interventional study in a rural area

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    BACKGROUND: UniNet is an Internet-based thematic network for a virtual community of users (VCU). It supports a virtual multidisciplinary community for physicians, focused on the improvement of clinical practice. This is a study of the effects of a thematic network such as UniNet on primary care medicine in a rural area, specifically as a platform of communication between specialists at the hospital and doctors in the rural area. METHODS: In order to study the effects of a thematic network such as UniNet on primary care medicine in a rural area, we designed an interventional study that included a control group. The measurements included the number of patient displacements due to disease, number of patient hospital stays and the number of prescriptions of drugs of low therapeutic utility and generic drug prescriptions by doctors. These data were analysed and compared with those of the control center. RESULTS: Our study showed positive changes in medical practice, reflected in the improvement of the evaluated parameters in the rural health area where the interventional study was carried out, compared with the control area. We discuss the strengths and weaknesses of UniNet as a potential medium to improve the quality of medical care in rural areas. CONCLUSION: The rural doctors had an effective, useful, user-friendly and cheap source of medical information that may have contributed to the improvement observed in the medical quality indices

    The International Natural Product Sciences Taskforce (INPST) and the power of Twitter networking exemplified through #INPST hashtag analysis

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    Background: The development of digital technologies and the evolution of open innovation approaches have enabled the creation of diverse virtual organizations and enterprises coordinating their activities primarily online. The open innovation platform titled "International Natural Product Sciences Taskforce" (INPST) was established in 2018, to bring together in collaborative environment individuals and organizations interested in natural product scientific research, and to empower their interactions by using digital communication tools. Methods: In this work, we present a general overview of INPST activities and showcase the specific use of Twitter as a powerful networking tool that was used to host a one-week "2021 INPST Twitter Networking Event" (spanning from 31st May 2021 to 6th June 2021) based on the application of the Twitter hashtag #INPST. Results and Conclusion: The use of this hashtag during the networking event period was analyzed with Symplur Signals (https://www.symplur.com/), revealing a total of 6,036 tweets, shared by 686 users, which generated a total of 65,004,773 impressions (views of the respective tweets). This networking event's achieved high visibility and participation rate showcases a convincing example of how this social media platform can be used as a highly effective tool to host virtual Twitter-based international biomedical research events

    Dynamic methods for catalytic kinetics

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    The application of various transient techniques in heterogeneous catalysis (TAP, step-response experiments, SSITKA, TEOM), with the aim to determine reaction kinetics for design purposes, is presented for several cases. These cases, comprising catalytic cracking, diffusion in zeolites, simultaneous NO, and SO, removal, syngas production from methane by chemical looping and selective catalytic reduction of NOx, show that transient techniques can be well used for the purpose of rapid determination of the reaction kinetics without the laborious classical approach of steady-state kinetic measurements and without the need of high levels of sophistication to interpret and process the experimental data. In this respect transient kinetics deserve, next to fundamental catalysis studies, more frequent application in design Studies for industrially relevant reaction systems. Topics and challenges for further developments in transient studies are indicated. (c) 2008 Elsevier B.V. All rights reserved

    New supported vanadia catalysts for oxidation reactions prepared by sputter deposition

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    Model vanadia catalysts were synthesised using magnetron sputtering of the active species for precisely controlled and clean catalyst design. Two series of supported vanadia catalysts were produced on inert beads with silica surface: vanadia/silica through single vanadia coating and vanadia/titania/silica by subsequent deposition of titania and vanadia. Loadings were varied by changing deposition time. All catalysts were characterised for structure and reducibility. Catalytic performance was tested by steady-state and transient experiments with propane oxidative dehydrogenation. Both supports yielded similar vanadia structures and equal dispersion. The vanadia loading strongly influenced structure and chemical behaviour. Shorter depositions gave surface vanadia monomers and polymers, whereas for longer depositions, crystalline species developed on either support. In propane oxidative dehydrogenation, very high turnover frequencies were obtained, especially for thinner depositions. An intermediate titania layer strongly influenced the vanadia activity. Maximum activity was obtained for a few vanadia layers supported on titania. (c) 2006 Elsevier Inc. All rights reserved
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