165 research outputs found

    Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation: Special Report of the Intergovernmental Panel on Climate Change

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    This Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX) has been jointly coordinated by Working Groups I (WGI) and II (WGII) of the Intergovernmental Panel on Climate Change (IPCC). The report focuses on the relationship between climate change and extreme weather and climate events, the impacts of such events, and the strategies to manage the associated risks. The IPCC was jointly established in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), in particular to assess in a comprehensive, objective, and transparent manner all the relevant scientific, technical, and socioeconomic information to contribute in understanding the scientific basis of risk of human-induced climate change, the potential impacts, and the adaptation and mitigation options. Beginning in 1990, the IPCC has produced a series of Assessment Reports, Special Reports, Technical Papers, methodologies, and other key documents which have since become the standard references for policymakers and scientists.This Special Report, in particular, contributes to frame the challenge of dealing with extreme weather and climate events as an issue in decisionmaking under uncertainty, analyzing response in the context of risk management. The report consists of nine chapters, covering risk management; observed and projected changes in extreme weather and climate events; exposure and vulnerability to as well as losses resulting from such events; adaptation options from the local to the international scale; the role of sustainable development in modulating risks; and insights from specific case studies

    Efectos del programa "Mi clase favorita" para la mejora de la producción oral del inglés en niños de primer grado de primaria de la IE FAP José A. Quiñones

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    Tesis para optar el título de Licenciada en EducaciónEsta tesis se propone mostrar que para lograr la habilidad en speaking (producción oral), una de las cuatro habilidades que conforman la enseñanza del idioma inglés (listening, speaking, reading, writing), es necesario que el docente conozca los principios que deben ser considerados para que esta competencia se haga posible. Enseñar el inglés no solo requiere que el docente posea dominio lingüístico sino también un dominio metodológico, de manera que propicie mejores aprendizajes en dicha lengua extranjera.Índice general Índice general .................................................................................................................. 2 Introducción .................................................................................................................... 4 CAPÍTULO I................................................................................................................... 7 PLANTEAMIENTO DEL PROBLEMA ..................................................................... 7 1.1. Descripción del problema.................................................................................... 7 1.1.1 Formulación del problema................................................................................ 10 1.2. Formulación de objetivos.................................................................................. 10 1.2.1. Objetivo general.................................................................................................. 10 1.2.2. Objetivos Específicos.......................................................................................... 11 1.3. Justificación.......................................................................................................... 11 1.4. Limitaciones de la investigación ........................................................................... 11 CAPÍTULO II .............................................................................................................. 13 MARCO TEÓRICO .................................................................................................... 13 2.1. Antecedentes de la investigación .......................................................................... 13 2.2 Bases teóricas........................................................................................................... 18 2.2.1. Recursos didácticos............................................................................................. 18 2.2.1.1 Clasificación de Recursos Didácticos. ............................................................. 19 2.2.1.2. Criterios para la clasificación de Recursos Didácticos................................. 21 2.2.2. Producción oral. .................................................................................................. 22 2.2.2.1. Tipos de situaciones de habla para los niños................................................. 24 2.2.2.2. Actividades comunicativas basadas en la precisión...................................... 24 2.2.2.3. Actividades comunicativas basadas en la fluidez.......................................... 24 2.2.3. Naturaleza del programa “Mi clase favorita”.................................................. 27 2.2.4. Objetivos del programa..................................................................................... 28 2.2.5. Formulación de las hipótesis............................................................................. 29 CAPÍTULO III.............................................................................................................. 30 METODOLOGÍA......................................................................................................... 30 3.1 Método de investigación ......................................................................................... 30 3.2 Diseño de investigación........................................................................................... 30 3.3 Sujetos de investigación.......................................................................................... 31 3.3.1 Criterios de inclusión y exclusión de la muestra ............................................... 31 3.4 Instrumentos............................................................................................................ 32 3.4.1 Programa “Mi clase favorita” ............................................................................ 32 3.4.2 Test de Cambrigde............................................................................................... 32 3.5 Procedimiento para la recolección de datos. ........................................................ 33 CAPÍTULO IV.............................................................................................................. 34 RESULTADOS ............................................................................................................. 34 4.1 Resultados................................................................................................................ 34 4.2 Resultados descriptivos .......................................................................................... 34 4.3 Contrastación de hipótesis ..................................................................................... 36 4.4 Análisis y discusión de resultados.......................................................................... 41 CAPÍTULO V ............................................................................................................... 44 CONCLUSIONES Y RECOMENDACIONES.......................................................... 44 5.1 Conclusiones....................................................................................................... 44 5.2 Recomendaciones.................................................................................................... 45 REFERENCIAS BIBLIOGRÁFICAS........................................................................ 46 ANEXO 1 DESARROLLO DEL PROGRAMA “MI CLASE FAVORITA”......... 49 ANEXO 2 ESTRUCTURA DEL TEST DE CAMBRIGDE ..................................... 62 ANEXO 3 RESULTADOS DE APLICACIÓN DEL PRE Y POST TEST ……….63Tesí

    Constraining the initial state granularity with bulk observables in Au+Au collisions at sNN=200\sqrt{s_{\rm NN}}=200 GeV

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    In this paper we conduct a systematic study of the granularity of the initial state of hot and dense QCD matter produced in ultra-relativistic heavy-ion collisions and its influence on bulk observables like particle yields, mTm_T spectra and elliptic flow. For our investigation we use a hybrid transport model, based on (3+1)d hydrodynamics and a microscopic Boltzmann transport approach. The initial conditions are generated by a non-equilibrium hadronic transport approach and the size of their fluctuations can be adjusted by defining a Gaussian smoothing parameter σ\sigma. The dependence of the hydrodynamic evolution on the choices of σ\sigma and tstartt_{start} is explored by means of a Gaussian emulator. To generate particle yields and elliptic flow that are compatible with experimental data the initial state parameters are constrained to be σ=1\sigma=1 fm and tstart=0.5t_{\rm start}=0.5 fm. In addition, the influence of changes in the equation of state is studied and the results of our event-by-event calculations are compared to a calculation with averaged initial conditions. We conclude that even though the initial state parameters can be constrained by yields and elliptic flow, the granularity needs to be constrained by other correlation and fluctuation observables.Comment: 14 pages, 8 figures, updated references, version to appear in J. Phys.

    Cell morphology governs directional control in swimming bacteria

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    The ability to rapidly detect and track nutrient gradients is key to the ecological success of motile bacteria in aquatic systems. Consequently, bacteria have evolved a number of chemotactic strategies that consist of sequences of straight runs and reorientations. Theoretically, both phases are affected by fluid drag and Brownian motion, which are themselves governed by cell geometry. Here, we experimentally explore the effect of cell length on control of swimming direction. We subjected Escherichia coli to an antibiotic to obtain motile cells of different lengths, and characterized their swimming patterns in a homogeneous medium. As cells elongated, angles between runs became smaller, forcing a change from a run-and-tumble to a run-and-stop/reverse pattern. Our results show that changes in the motility pattern of microorganisms can be induced by simple morphological variation, and raise the possibility that changes in swimming pattern may be triggered by both morphological plasticity and selection on morphology

    The alpha(2)delta auxiliary subunit reduces affinity of omega-conotoxins for recombinant N-type (Ca(v)2.2) calcium channels

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    The omega-conotoxins from fish-hunting cone snails are potent inhibitors of voltage-gated calcium channels. The omega-conotoxins MVIIA and CVID are selective N-type calcium channel inhibitors with potential in the treatment of chronic pain. The beta and alpha(2)delta-1 auxiliary subunits influence the expression and characteristics of the alpha(1B) subunit of N-type channels and are differentially regulated in disease states, including pain. In this study, we examined the influence of these auxiliary subunits on the ability of the omega-conotoxins GVIA, MVIIA, CVID and analogues to inhibit peripheral and central forms of the rat N-type channels. Although the beta3 subunit had little influence on the on- and off-rates of omega-conotoxins, coexpression of alpha(2)delta with alpha(1B) significantly reduced on- rates and equilibrium inhibition at both the central and peripheral isoforms of the N-type channels. The alpha(2)delta also enhanced the selectivity of MVIIA, but not CVID, for the central isoform. Similar but less pronounced trends were also observed for N-type channels expressed in human embryonic kidney cells. The influence of alpha(2)delta was not affected by oocyte deglycosylation. The extent of recovery from the omega-conotoxin block was least for GVIA, intermediate for MVIIA, and almost complete for CVID. Application of a hyperpolarizing holding potential ( - 120 mV) did not significantly enhance the extent of CVID recovery. Interestingly, [R10K] MVIIA and [O10K] GVIA had greater recovery from the block, whereas [K10R] CVID had reduced recovery from the block, indicating that position 10 had an important influence on the extent of omega-conotoxin reversibility. Recovery from CVID block was reduced in the presence of alpha(2)delta in human embryonic kidney cells and in oocytes expressing alpha(1B-b). These results may have implications for the antinociceptive properties of omega-conotoxins, given that the alpha(2)delta subunit is up-regulated in certain pain states

    State of the Antarctic and Southern Ocean Climate System

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    This paper reviews developments in our understanding of the state of the Antarctic and Southern Ocean climate and its relation to the global climate system over the last few millennia. Climate over this and earlier periods has not been stable, as evidenced by the occurrence of abrupt changes in atmospheric circulation and temperature recorded in Antarctic ice core proxies for past climate. Two of the most prominent abrupt climate change events are characterized by intensification of the circumpolar westerlies (also known as the Southern Annular Mode) between ∼6000 and 5000 years ago and since 1200–1000 years ago. Following the last of these is a period of major trans-Antarctic reorganization of atmospheric circulation and temperature between A.D. 1700 and 1850. The two earlier Antarctic abrupt climate change events appear linked to but predate by several centuries even more abrupt climate change in the North Atlantic, and the end of the more recent event is coincident with reorganization of atmospheric circulation in the North Pacific. Improved understanding of such events and of the associations between abrupt climate change events recorded in both hemispheres is critical to predicting the impact and timing of future abrupt climate change events potentially forced by anthropogenic changes in greenhouse gases and aerosols. Special attention is given to the climate of the past 200 years, which was recorded by a network of recently available shallow firn cores, and to that of the past 50 years, which was monitored by the continuous instrumental record. Significant regional climate changes have taken place in the Antarctic during the past 50 years. Atmospheric temperatures have increased markedly over the Antarctic Peninsula, linked to nearby ocean warming and intensification of the circumpolar westerlies. Glaciers are retreating on the peninsula, in Patagonia, on the sub-Antarctic islands, and in West Antarctica adjacent to the peninsula. The penetration of marine air masses has become more pronounced over parts of West Antarctica. Above the surface, the Antarctic troposphere has warmed during winter while the stratosphere has cooled year-round. The upper kilometer of the circumpolar Southern Ocean has warmed, Antarctic Bottom Water across a wide sector off East Antarctica has freshened, and the densest bottom water in the Weddell Sea has warmed. In contrast to these regional climate changes, over most of Antarctica, near-surface temperature and snowfall have not increased significantly during at least the past 50 years, and proxy data suggest that the atmospheric circulation over the interior has remained in a similar state for at least the past 200 years. Furthermore, the total sea ice cover around Antarctica has exhibited no significant overall change since reliable satellite monitoring began in the late 1970s, despite large but compensating regional changes. The inhomogeneity of Antarctic climate in space and time implies that recent Antarctic climate changes are due on the one hand to a combination of strong multidecadal variability and anthropogenic effects and, as demonstrated by the paleoclimate record, on the other hand to multidecadal to millennial scale and longer natural variability forced through changes in orbital insolation, greenhouse gases, solar variability, ice dynamics, and aerosols. Model projections suggest that over the 21st century the Antarctic interior will warm by 3.4° ± 1°C, and sea ice extent will decrease by ∼30%. Ice sheet models are not yet adequate enough to answer pressing questions about the effect of projected warming on mass balance and sea level. Considering the potentially major impacts of a warming climate on Antarctica, vigorous efforts are needed to better understand all aspects of the highly coupled Antarctic climate system as well as its influence on the Earth\u27s climate and oceans

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

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    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

    Inhibitory muscarinic acetylcholine receptors enhance aversive olfactory learning in adult Drosophila

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    Olfactory associative learning in Drosophila is mediated by synaptic plasticity between the Kenyon cells of the mushroom body and their output neurons. Both Kenyon cells and their inputs from projection neurons are cholinergic, yet little is known about the physiological function of muscarinic acetylcholine receptors in learning in adult flies. Here we show that aversive olfactory learning in adult flies requires type A muscarinic acetylcholine receptors (mAChR-A), particularly in the gamma subtype of Kenyon cells. mAChR-A inhibits odor responses and is localized in Kenyon cell dendrites. Moreover, mAChR-A knockdown impairs the learning-associated depression of odor responses in a mushroom body output neuron. Our results suggest that mAChR-A function in Kenyon cell dendrites is required for synaptic plasticity between Kenyon cells and their output neurons
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