82 research outputs found

    Key paramaters in the design of HiPER reaction chamber

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    The future chamber reactor of HiPER will have to withstand short energy pulses (3 μs long) of up to 5 MJ of charged particles and X-rays with different repetition rates. Nowadays, tungsten has been selected as first wall material for a 5m radius reaction chamber. From the thermo-mechanical point of view, experiments have demonstrated that tungsten can withstand heat flux parameters up to 28 MJm-2 s -1/2 without roughening and 40 MJm-2 s -1/2 without undergoing melting. From the atomic point of view, He retention and bubble formation represents the biggest threat to its survivability, being doses of ~10 17 He/cm2 the upper limit for safe operation. Comparison of these limiting values with those proposed for a 48 MJ shock ignition target in HiPER reveals that, under a reasonable plan of 1000 fusion shots during the chamber lifetime, tungsten should guarantee a proper performance of the first wall

    Prevalencia del síndrome metabólico en población laboral española: registro MESYAS

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    Introducción y objetivos. Estudiar la prevalencia del síndrome metabólico (SM) en la población laboral activa española y analizar sus diferencias según las categorías laborales. Sujetos y método. Se recogieron los datos de 7.256 trabajadores activos (un 82,4% varones), con una edad media de 45,4 ± 9,8 años, empleados en una factoría de coches y unos grandes almacenes. El diagnóstico del SM se realizó mediante los criterios modificados del ATP-III (se utilizó el índice de masa corporal en lugar del perímetro abdominal). Resultados. La prevalencia bruta del SM fue del 10,2%. Ajustada por edad y sexo en una población plana (20-60 años) fue del 5,8% (intervalo de confianza [IC] del 95%, 4,1-7,6%), significativamente más alta en varones que en mujeres (el 8,7%; IC del 95%, 7,3-10,0 frente al 3,0%; IC del 95%, 0,8-5,1). Todos los componentes del SM fueron significativamente más prevalentes en varones, excepto las concentraciones de lipoproteínas de alta densidad, que fueron más bajas. La prevalencia aumentó con la edad y el sexo masculino (odds ratio [OR] = 1,7), la obesidad (OR = 9,6), la hipertensión (OR = 3,4) y la diabetes (OR = 15,4). Los trabajadores manuales presentaron la mayor prevalencia de SM (11,8%), seguidos por EPIDEMIOLOGÍA Y PREVENCIÓN Prevalencia del síndrome metabólico en población laboral española: registro MESYAS Eduardo Alegríaa, Alberto Corderoa, Martín Laclaustrab, Alberto Grimac, Montserrat Leónb, José A. Casasnovasb, Emilio Luengod, Alfonso del Ríob e Ignacio Ferreirab, en representación de los investigadores del registro MESYAS* aDepartamento de Cardiología. Clínica Universitaria de Navarra. Pamplona. Navarra. España. bUnidad de Investigación Cardiovascular. Hospital Clínico Universitario. Zaragoza. España. cServicio de Cardiología Preventiva. Asepeyo. Valencia. España. dServicio de Cardiología. Hospital Militar. Zaragoza. España. *Al final del artículo se relacionan los miembros del equipo de investigación MESYAS. Martín Laclaustra está contratado como investigador en el Instituto Aragonés de Ciencias de la Salud dentro del programa de ayudas a contratos para investigadores que han finalizado su formación médica especializada del Instituto de Salud Carlos III. El registro MESYAS cuenta con una beca de la Sociedad Española de Cardiología (Sevilla, 2003) y la Sección de Cardiología Preventiva y Rehabilitadora. Correspondencia: Dr. E. Alegría Ezquerra. Departamento de Cardiología. Clínica Universitaria de Navarra. Avda. Pío XII, 36. 31008 Pamplona. Navarra. España. Correo electrónico: [email protected] Recibido el 5 de octubre de 2004. Aceptado para su publicación el 18 de marzo de 2005. los trabajadores de oficina (9,3%) y los directivos (7,7%) (gradiente social inverso). Los trabajadores manuales tienen un riesgo superior de presentar SM, con independencia de la edad y el sexo (OR = 1,3); este efecto parece depender de las concentraciones de triglicéridos. Conclusiones. Uno de cada 10 trabajadores activos tiene SM; la prevalencia aumenta con la edad y el sexo masculino. La obesidad y la diabetes suponen gran incremento de la prevalencia. Los trabajadores manuales son el colectivo con mayor prevalencia

    Rapid Intensity Decrease During the Second Half of the First Millennium BCE in Central Asia and Global Implications

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    Recent paleomagnetic studies have shown that important short-lived intensity fluctuations occurred during the first millennium BCE. However, the knowledge of the spatial and temporal extension of these features is still limited by the scarce availability of robust data. In this study we focus on the study of the intensity decrease that took place in Central Asia during the second half of the 1st millennium BCE after the high intensities that characterized the Levantine Iron Age Anomaly. Since previous archeointensities available for this period and region were obtained without accomplishing modern standards of quality, we present here new archeointensities that are derived from classical Thellier and Thellier experiments, including partial thermoremanent magnetization (pTRM) checks, thermoremanent magnetization (TRM) anisotropy and cooling rate corrections at the specimen level. The new 51 archeointensities, together with previous archeointensities, have been used to present a new local paleosecular variation curve for Central Asia. The results confirm the existence of an important geomagnetic field intensity decrease in South Uzbekistan from the 4th century BCE to the end of the 1st century BCE associated with rates of changes up to −15 μT/century. A critical analysis of the archeointensity global database indicates that this feature was present at continental scale, from Western Europe to Central Asia. However, this trend is not identified in other regions such as Japan or Mexico. Finally, the comparison with the dipole moment derived from recent global geomagnetic field reconstructions suggests a strong influence of non-dipolar sources upon this continental intensity feature.Financial support was given by the Spanish Ministry of Science and Innovation thorough the projects CERAC (HAR2016-75133-C3-1-P), CONCERAC (HAR2016-75133-C3-3-P), SPYKE (CGL2017-87015-P), SÚMATE (PID2020-113316GB-I00) and PULSES 5.K (PID2020-117105RB-I00). R. Bonilla-Alba thanks the FPI fellowship (PRE2018-085949) associated with the SPYKE project. This study has been also funded by the Ramón y Cajal program (contracts of M. Gómez-Paccard and V. Martínez-Ferreras, refs. RYC-2013-14405 and RYC-2014-15789). The authors wish to acknowledge the professional support of the CSIC Interdisciplinary Thematic Platform Open Heritage: Research and Society (PTI-PAIS). E. Beamud thanks the Geomodels Research Institute (UB) and the Grup de Geodinàmica i Anàlisi de Conques-2017SGR596 (Generalitat de Catalunya). A. Palencia-Ortas thanks the PTA contract of the Spanish Ministry of Science and Innovation

    Variation in plasma oxidative status and testosterone level in relation to egg-eviction effort and age of brood-parasitic common cuckoo nestlings

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    To avoid competition for parental care, brood-parasitic Common Cuckoo (Cuculus canorus) nestlings evict all of the host's eggs and nestlings within a few days after hatching. Little is known about the physiological effects of eviction behavior on the cuckoo nestling's oxidative balance or about age-related variation in plasma oxidative status and testosterone level of developing birds. We examined whether the cuckoo nestling's plasma oxidative status was related to prior effort in eviction and quantified variation in the level of reactive oxygen metabolites, of nonenzymatic antioxidant capacity, and of testosterone concentration in plasma at various phases of the cuckoo's development. Levels of both reactive oxygen metabolites and antioxidant capacity were greater in older than in younger nestlings, suggesting that younger nestlings effectively counterbalance their increased production of free radicals, whereas, near fledging, levels of reactive oxygen metabolites increase despite improved antioxidant capacity. Possibly, overall energy expenditure increases with age and elevates the production of reactive oxygen species to a rate higher than what the antioxidant system could eliminate. Plasma testosterone level was the highest at nestlings' intermediate phase of growth. High levels of testosterone may be required during the period of fastest growth, and when the growth rate levels off near fledging, testosterone levels may also decline. Cuckoo chicks that evicted more host eggs from steeper nests had higher plasma levels of reactive oxygen metabolites shortly after the eviction period, suggesting that eviction is costly in terms of an increased level of oxidative stress. Para evitar la competencia por el cuidado parental, los polluelos parásitos de nidada de Cuculus canorus desalojan todos los huevos y los polluelos del hospedador a los pocos días después de la eclosión. Se sabe poco sobre los efectos fisiológicos del comportamiento de desalojo en el balance oxidativo de los polluelos de C. canorus o sobre la variación en el estatus oxidativo del plasma y el nivel de testosterona relacionado con la edad de las aves en desarrollo. Examinamos si el estatus oxidativo del plasma de los polluelos de C. canorus se relacionaba con un esfuerzo previo de desalojo y cuantificamos la variación en el nivel de metabolitos reactivos de oxígeno, la capacidad antioxidante no enzimática y la concentración de testosterona en el plasma en varias fases del desarrollo de C. canorus. Tanto los niveles de metabolitos reactivos de oxígeno como la capacidad antioxidante fueron superiores en los polluelos de mayor edad que en los más jóvenes, lo que sugiere que los polluelos de menor edad contrarrestan eficazmente el aumento de la producción de radicales libres, mientras que, cuando se apróximan al abandono del nido, los niveles de metabolitos reactivos de oxígeno aumentan a pesar de una mejora en la capacidad antioxidante. Posiblemente, el gasto total de energía se incrementa con la edad, elevándose la producción de formas reactivas de oxígeno a una tasa mayor de la que el sistema antioxidante puede eliminar. El nivel de testosterona en el plasma fue máximo en la fase intermedia del crecimiento de los polluelos. Pueden requerirse altos niveles de testosterona durante el período de mayor crecimiento y, cuando la tasa de crecimiento se estabiliza cerca del abandono del nido, los niveles de testosterona también podrián disminuir. Los polluelos de C. canorus que desalojaron más huevos del hospedador en nidos con una estructura más empinada tuvieron niveles de plasma de metabolitos reactivos de oxígeno en plasma más altos poco después del período de desalojo, sugiriendo que el desalojo es costoso en términos de un incremento en el nivel de estrés oxidativo

    Rapid Intensity Decrease During the Second Half of the First Millennium BCE in Central Asia and Global Implications

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    Recent paleomagnetic studies have shown that important short-lived intensity fluctuations occurred during the first millennium BCE. However, the knowledge of the spatial and temporal extension of these features is still limited by the scarce availability of robust data. In this study we focus on the study of the intensity decrease that took place in Central Asia during the second half of the 1st millennium BCE after the high intensities that characterized the Levantine Iron Age Anomaly. Since previous archeointensities available for this period and region were obtained without accomplishing modern standards of quality, we present here new archeointensities that are derived from classical Thellier and Thellier experiments, including partial thermoremanent magnetization (pTRM) checks, thermoremanent magnetization (TRM) anisotropy and cooling rate corrections at the specimen level. The new 51 archeointensities, together with previous archeointensities, have been used to present a new local paleosecular variation curve for Central Asia. The results confirm the existence of an important geomagnetic field intensity decrease in South Uzbekistan from the 4th century BCE to the end of the 1st century BCE associated with rates of changes up to -15 mu T/century. A critical analysis of the archeointensity global database indicates that this feature was present at continental scale, from Western Europe to Central Asia. However, this trend is not identified in other regions such as Japan or Mexico. Finally, the comparison with the dipole moment derived from recent global geomagnetic field reconstructions suggests a strong influence of non-dipolar sources upon this continental intensity feature

    Socio-Demographic Health Determinants Are Associated with Poor Prognosis in Spanish Patients Hospitalized with COVID-19

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    Introduction Social vulnerability is a known determinant of health in respiratory diseases. Our aim was to identify whether there are socio-demographic factors among COVID-19 patients hospitalized in Spain and their potential impact on health outcomes during the hospitalization. Methods A multicentric retrospective case series study based on administrative databases that included all COVID-19 cases admitted in 19 Spanish hospitals from 1 March to 15 April 2020. Socio-demographic data were collected. Outcomes were critical care admission and in-hospital mortality. Results We included 10,110 COVID-19 patients admitted to 18 Spanish hospitals (median age 68 (IQR 54–80) years old; 44.5% female; 14.8% were not born in Spain). Among these, 779 (7.7%) cases were admitted to critical care units and 1678 (16.6%) patients died during the hospitalization. Age, male gender, being immigrant, and low hospital saturation were independently associated with being admitted to an intensive care unit. Age, male gender, being immigrant, percentile of average per capita income, and hospital experience were independently associated with in-hospital mortality. Conclusions Social determinants such as residence in low-income areas and being born in Latin American countries were associated with increased odds of being admitted to an intensive care unit and of in-hospital mortality. There was considerable variation in outcomes between different Spanish centers.JPA is under contract within the Ramón y Cajal Program (RYC-2016-20155, Ministerio de Economía, Industria y Competitividad, Spain). Investigators of Spanish Social-Environmental COVID-19 Register: Steering Committee: F. Javier Martín-Sánchez, Adrián Valls Carbó, Carmen Martínez Valero, Juan de D. Miranda, Juan Pedro Arrebola, Marta Esteban López, Annika Parviainen, Òscar Miró, Pere Llorens, Sònia Jiménez, Pascual Piñera, Guillermo Burillo, Alfonso Martín, Jorge García Lamberechts, Javier Jacob, Aitor Alquézar, Juan González del Castillo, Amanda López Picado and Iván Núñez. Participating centers: Oscar Miró y Sonia Jimenez. Hospital Clinic de Barcelona. José María Ferreras Amez. Hospital Clínico Universitario Lozano Blesa. Rafael Rubio Díaz. Complejo Hospitalario de Toledo. Julio Javier Gamazo del Rio. Hospital Universitario de Galdakao. Héctor Alonso. Hospital Universitario Miguel de Valdecilla. Pablo Herrero. Hospital Universitario Central de Asturias. Noemí Ruiz de Lobera. Hospital San Pedro de Logroño. Carlos Ibero. Complejo Hospitalario de Navarra. Plácido Mayan. Hospital Clínico Universitario de Santiago. Rosario Peinado. Complejo Hospitalario Universitario de Badajoz. Carmen Navarro Bustos. Hospital Universitario Virgen de la Macarena. Jesús Álvarez Manzanares. Hospital Universitario Rio Hortega. Francisco Román. Hospital Universitario General de Alicante. Pascual Piñera. Hospital Universitario Reina Sofia de Murcia. Guillermo Burillo. Hospital Universitario de Canarias de Tenerife. Javier Jacob. Hospital Universitario de Bellvitge. Carlos Bibiano. Hospital Universitario Infanta Leonor.Peer reviewe

    Inhibitory effects of pharmacological doses of melatonin on aromatase activity and expression in rat glioma cells

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    Melatonin exerts oncostatic effects on different kinds of neoplasias, especially on oestrogen-dependent tumours. Recently, it has been described that melatonin, on the basis of its antioxidant properties, inhibits the growth of glioma cells. Glioma cells express oestrogen receptors and have the ability to synthesise oestrogens from androgens. In the present study, we demonstrate that pharmacological concentrations of melatonin decreases the growth of C6 glioma cells and reduces the local biosynthesis of oestrogens, through the inhibition of aromatase, the enzyme that catalyses the conversion of androgens into oestrogens. These results are supported by three types of evidence. Firstly, melatonin counteracts the growth stimulatory effects of testosterone on glioma cells, which is dependent on the local synthesis of oestrogens from testosterone. Secondly, we found that melatonin reduces the aromatase activity of C6 cells, measured by the tritiated water release assay. Finally, by (RT)–PCR, we found that melatonin downregulates aromatase mRNA steady-state levels in these glioma cells. We conclude that melatonin inhibits the local production of oestrogens decreasing aromatase activity and expression. By analogy to the implications of aromatase in other forms of oestrogen-sensitive tumours, it is conceivable that the modulation of the aromatase by pharmacological melatonin may play a role in the growth of glioblastomas

    Consumer–brand identification revisited: An integrative framework of brand identification, customer satisfaction, and price image and their role for brand loyalty and word of mouth

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    Consumer–brand identification has received considerable attraction among scholars and practitioners in recent years. We contribute to previous research by proposing an integrative model that includes consumer–brand identification, customer satisfaction, and price image to investigate the interrelationships among these constructs as well as their effects on brand loyalty and positive word of mouth. To provide general results, we empirically test the model using a sample of 1443 respondents from a representative consumer panel and 10 service/product brands. The results demonstrate that identification, satisfaction, and price image significantly influence both loyalty and word of mouth. Moreover, we find significant interrelationships among the constructs: Identification positively influences both satisfaction and price image, which also increases satisfaction. By disclosing the relative importance of three separate ways of gaining and retaining customers, this study helps managers more appropriately choose the right mix of branding, pricing, and relationship marketing. From an academic point of view, our research is the first to explicitly examine the effects of the concept of identification for price management and to integrate variables from the fields of branding, relationship marketing, and behavioral pricing, which have separately been identified as particularly important determinants of marketing outcomes

    Measurement of ϒ production in pp collisions at √s = 2.76 TeV

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    The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons decaying into the dimuon final state is studied with the LHCb detector using a data sample corresponding to an integrated luminosity of 3.3 pb−1 collected in proton–proton collisions at a centre-of-mass energy of √s = 2.76 TeV. The differential production cross-sections times dimuon branching fractions are measured as functions of the ϒ transverse momentum and rapidity, over the ranges pT < 15 GeV/c and 2.0 < y < 4.5. The total cross-sections in this kinematic region, assuming unpolarised production, are measured to be σ (pp → ϒ(1S)X) × B ϒ(1S)→μ+μ− = 1.111 ± 0.043 ± 0.044 nb, σ (pp → ϒ(2S)X) × B ϒ(2S)→μ+μ− = 0.264 ± 0.023 ± 0.011 nb, σ (pp → ϒ(3S)X) × B ϒ(3S)→μ+μ− = 0.159 ± 0.020 ± 0.007 nb, where the first uncertainty is statistical and the second systematic
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