5,951 research outputs found
Measurement of tW the production cross-section at 13 TeV with CMS
The inclusive cross-section for tW production in proton-proton collisions at
TeV is measured with a dataset corresponding to an integrated
luminosity of 35.9 fb collected by the CMS experiment. The measurement
is performed in events with one electron and one muon, and exploits kinematic
differences between the signal and the dominating background through
the use of multivariate discriminants designed to separate the two processes.
The measured cross-section of pb is in agreement with standard model
expectations
Dejar la profesión docente: análisis del papel del apoyo social, el engagement y la inteligencia emocional en la intención de abandono del profesorado
The study aimed to test mediator and moderator factors in the relationship between workplace social support (i.e., perceived support from colleagues and supervisors) and intentions to quit in a sample of teaching professionals. Specifically, utilizing job-demands-resources theory to focus on social support, we examined whether work engagement mediated the relationship between workplace social support and intentions to quit. Moreover, the potential moderator role of emotional intelligence in the proposed model was tested. The study sample comprised 1,297 teaching professionals (64.8% females) working as preschool, primary, and secondary teachers in several centers in eastern and southern Spain. The main results demonstrated that work engagement totally mediated the relationship between social support from colleagues/supervisors and intentions to quit. The findings showed that teachers’ levels of emotional intelligence significantly moderated the indirect paths between perceived support from colleagues/supervisors and intentions to quit. Teachers with the lowest levels of work engagement reported low support from colleagues or supervisors, togetherwith low emotional intelligence. Similarly, highest intentions to quit was reported by those teachers reporting low work engagement and low emotional intelligence. Finally, we discuss the relevance of these findings for basic and applied research seeking to retain a more engaged teaching force.Este estudio pretende evaluar los factores mediadores y moderadores en la relación entre el apoyo social organizacional (apoyo percibido de compañeros y supervisores) y los niveles de intención de abandono en una muestra de profesionales de la enseñanza. Específicamente, usando la teoría de demandas y recursos laborales y centrándose en el apoyo social, se examina si el engagement laboral media la relación entre apoyo social organizacional e intención de abandono. Además, se analiza el posible papel moderador de la inteligencia emocional en el modelo propuesto. La muestra del estudio esta compuesta por 1,297 profesionales de la enseñanza (64.8% mujeres) que trabajaban como docentes de Infantil, Primaria y Secundaria en varios centros del este y sur de España. Los resultados principales demostraron que el engagement laboral mediaba totalmente la relación entre el apoyo social de compañeros y supervisores y la intención de abandono. Los hallazgos mostraron que el nivel de inteligencia emocional de los docentes moderaba significativamente las relaciones indirectas entre el apoyo percibido de compañeros y supervisores y la intención de abandono. Los docentes con un nivel más bajo de engagement laboral informaron de bajo apoyo de compañeros y supervisores, así como de un bajo nivel de inteligencia emocional. Igualmente, aquellos docentes con bajo engagement laboral y baja inteligencia emocional informaron de mayores niveles de intención de abandono. Finalmente, se discute la importancia de estos hallazgos para la investigación básica y aplicada enfocada a la retención de un capital docente comprometido
Influence of Embankments with Parapets on the Cross-Wind Turbulence Intensity at the Contact Wire of Railway Overheads
Winds as an environmental factor can cause significant difficulties for the railway system operation. The railway overhead has been particularly vulnerable to cross-winds related problems, such as development of undamped oscillations due to galloping phenomenon. The installation of windbreaks to decrease the aerodynamic loads on the train can affect the loads on railway overheads triggering cable galloping. One essential parameter to indicate the influence of the parapet wake on the catenary contact wire is the turbulence intensity. In this paper the results of an experimental analysis of the turbulence intensity due to the presence of parapets carried out in a wind tunnel are reported. Embankments equipped with different parapets have been tested and turbulence intensity has been measured at both contact wire locations, windward and leeward. The relative influence of the parapets is measured through a reduced turbulence intensity, defined as the ratio between the turbulence intensity measured with parapet and the turbulence intensity in the case without any parapet on the embankment. In general the reduced turbulence intensity increases as the height of the parapet increases
E-commerce and Business Case of a US E-commerce firm
What do we know as E-commerce and E-Business? Unique features of E-commerce. Types of E-commerce. History and feature of E-commerce. Why does E-commerce develop better in some places than in others? What make a current E-commerce success? Introduction of the US E-commerce firm studied. Bussiness case (customer, product, company and competition). Conclusions.Outgoin
The Impact of the Financial Crisis on Poverty and Income Distribution: Insights from Simulations in Selected Countries
As the financial crisis has spread through the world, the lack of real-time data has made it difficult to track its impact in developing countries. We use a microsimulation approach to assess the poverty and distributional effects of the crisis. In Bangladesh, Mexico, and the Philippines, we find increases in both the level and the depth of aggregate poverty. Income shocks are relatively large in the middle (and, in Mexico, the bottom) parts of the income distribution. We also find that characteristics of people who become poor because of the crisis are different from those of both chronically poor people and the general population. Our findings will be useful for policy makers wishing to identify leading monitoring indicators to track the impact of macroeconomic shocks and to design policies that protect vulnerable groups.Financial crisis, poverty, income, income distribution, developing countries, Bangladesh, Mexico, Philippines, macroeconomic shocks, poor
Assessing poverty and distributional impacts of the global crisis in the Philippines : a microsimulation approach
As the financial crisis has spread through the world, the lack of real-time data has made it difficult to track its impact in developing countries. This paper uses a micro-simulation approach to assess the poverty and distributional effects of the crisis in the Philippines. The authors find increases in both the level and the depth of aggregate poverty. Income shocks are relatively large in the middle part of the income distribution. They also find that characteristics of people who become poor because of the crisis are different from those of both chronically poor people and the general population. The findings can be useful for policy makers wishing to identify leading monitoring indicators to track the impact of macroeconomic shocks and to design policies that protect vulnerable groups.Rural Poverty Reduction,Regional Economic Development,Labor Policies,Achieving Shared Growth,Economic Theory&Research
Assessing ex ante the poverty and distributional impact of the global crisis in a developing country : a micro-simulation approach with application to Bangladesh
Measuring the poverty and distributional impact of the global crisis for developing countries is not easy, given the multiple channels of impact and the limited availability of real-time data. Commonly-used approaches are of limited use in addressing questions like who are being affected by the crisis and by how much, and who are vulnerable to falling into poverty if the crisis deepens? This paper develops a simple micro-simulation method, modifying models from existing economic literature, to measure the poverty and distributional impact of macroeconomic shocks by linking macro projections with pre-crisis household data. The approach is then applied to Bangladesh to assess the potential impact of the slowdown on poverty and income distribution across different groups and regions. A validation exercise using past data from Bangladesh finds that the model generates projections that compare well with actual estimates from household data. The results can inform the design of crisis monitoring tools and policies in Bangladesh, and also illustrate the kind of analysis that is possible in other developing countries with similar data availability.Rural Poverty Reduction,Regional Economic Development,Achieving Shared Growth,Economic Theory&Research
Subnormothermic Perfusion in the Isolated Rat Liver Preserves the Antioxidant Glutathione and Enhances the Function of the Ubiquitin Proteasome System.
The reduction of oxidative stress is suggested to be one of the main mechanisms to explain the benefits of subnormothermic perfusion against ischemic liver damage. In this study we investigated the early cellular mechanisms induced in isolated rat livers after 15 min perfusion at temperatures ranging from normothermia (37°C) to subnormothermia (26°C and 22°C). Subnormothermic perfusion was found to maintain hepatic viability. Perfusion at 22°C raised reduced glutathione levels and the activity of glutathione reductase; however, lipid and protein oxidation still occurred as determined by malondialdehyde, 4-hydroxynonenal-protein adducts, and advanced oxidation protein products. In livers perfused at 22°C the lysosomal and ubiquitin proteasome system (UPS) were both activated. The 26S chymotrypsin-like (β5) proteasome activity was significantly increased in the 26°C (46%) and 22°C (42%) groups. The increased proteasome activity may be due to increased Rpt6 Ser120 phosphorylation, which is known to enhance 26S proteasome activity. Together, our results indicate that the early events produced by subnormothermic perfusion in the liver can induce oxidative stress concomitantly with antioxidant glutathione preservation and enhanced function of the lysosomal and UPS systems. Thus, a brief hypothermia could trigger antioxidant mechanisms and may be functioning as a preconditioning stimulus
Problematización de la responsabilidad social o colectiva
Se pretende contribuir a la problematización del concepto de Responsabilidad Social o Colectiva, no sólo en términos de un deber ser incuestionable y una forma de actuación plural e inclusiva, sino además de una intervención vigilante y cooperativa de los ciudadanos. Para ello, se argumenta a favor de elaborar el pensamiento de ese concepto desde una doble perspectiva: con Giles Deleuze, quien exige un verdadero pensamiento como condición de cualquier problematización; y con Hannah Arendt, quien demuestra la necesidad de asumir la responsabilidad colectiva como una cuestión moral para la supervivencia de la humanidad. Esto supone mover el objeto del pensamiento en torno al vacío del mal, cuando no se actúa a favor de la vida
On the rotation periods of the components of the triple system TYC9300-0891-1AB/TYC9300-0529-1 in the Octans Association
Stellar rotation depends on different parameters. The range of values of
these parameters causes the dispersion in the rotation period distributions
observed in young stellar clusters/associations. We focus our investigation on
the effects of different circumstellar environments on stellar rotation. More
specifically, we are searching in stellar Associations for visual triple
systems where all stellar parameters are similar, with the only exceptions of
the unknown initial rotation period, and of the circum-stellar environment, in
the sense that one of the two about equal-mass components has a close-by third
'perturber' component. In the present study we analyse the 35-Myr old visual
triple system TYC 9300-0891-1AB + TYC 9300-0529-1 in the young Octans stellar
association consisting of three equal-mass K0V components. We collected from
the literature all information that allowed us to infer that the three
components are actually physically bound forming a triple system and are
members of the Octans Association. We collected broad-band photometric
timeseries in two observation seasons. We discovered that all the components
are variable, magnetically active, and from periodogram analysis we found the
unresolved components TYC 9300-0891-1AB to have a rotation period P = 1.383d
and TYC 9300-0529-1 a rotation period P = 1.634d. TYC 9300-0891-1A, TYC
9300-0891-1B, and TYC 9300-0529-1 have same masses, ages, and initial chemical
compositions. The relatively small 16% rotation period difference measured by
us indicates that all components had similar initial rotation periods and disc
lifetimes, and the separation of 157AU between the component A and the
'perturber' component B (or vice-versa) has been sufficiently large to prevent
any significant perturbation/shortening of the accretion-disc lifetime.Comment: Accepted by New Astronomy 201
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