2,142 research outputs found
Functional anatomy of non-REM sleep
The state of non-REM sleep (NREM), or slow wave sleep, is associated with a synchronized
EEG pattern in which sleep spindles and/or K complexes and high-voltage slow wave
activity (SWA) can be recorded over the entire cortical surface. In humans, NREM is subdivided
into stages 2 and 3–4 (presently named N3) depending on the proportions of each
of these polygraphic events. NREM is necessary for normal physical and intellectual performance
and behavior. An overview of the brain structures involved in NREM generation
shows that the thalamus and the cerebral cortex are absolutely necessary for the most
significant bioelectric and behavioral events of NREM to be expressed; other structures
like the basal forebrain, anterior hypothalamus, cerebellum, caudal brain stem, spinal cord
and peripheral nerves contribute to NREM regulation and modulation. In NREM stage 2,
sustained hyperpolarized membrane potential levels resulting from interaction between
thalamic reticular and projection neurons gives rise to spindle oscillations in the membrane
potential; the initiation and termination of individual spindle sequences depends on
corticothalamic activities. Cortical and thalamic mechanisms are also involved in the generation
of EEG delta SWA that appears in deep stage 3–4 (N3) NREM; the cortex has
classically been considered to be the structure that generates this activity, but delta oscillations
can also be generated in thalamocortical neurons. NREM is probably necessary to
normalize synapses to a sustainable basal condition that can ensure cellular homeostasis.
Sleep homeostasis depends not only on the duration of prior wakefulness but also on its
intensity, and sleep need increases when wakefulness is associated with learning. NREM
seems to ensure cell homeostasis by reducing the number of synaptic connections to a
basic level; based on simple energy demands, cerebral energy economizing during NREM
sleep is one of the prevalent hypotheses to explain NREM homeostasis.Grant BFU2009-06991/BFI from the Spanish Ministry of Science
and Innovation supported this wor
Evaluating the Chile Solidario program: results using the Chile Solidario panel and the administrative databases
This paper presents the results of a three-year evaluation performed on the first cohorts of Chile Solidario, the most important anti-poverty program in Chile. The paper presents a description of the program, emphasizing the mechanism by which people were admitted into the program. We then propose evaluation strategies and discuss their validity. The final evaluation is conducted using a Matching estimator, and we discuss the principles surrounding the potential for this to be a valid evaluation method. The initial results using the Chile Solidario Panel suggest that the program had positive effects on psychosocial welfare and on take-up of subsidies and social programs. However, it is not possible to obtain reliable results due to data shortcomings, particularly the lack of baseline data. In order to solve the problem, we generated a database using six years of administrative data, including around 1,000,000 family records per year. A method for overcoming the treatment substitution problem is discussed and implemented. Results are much more robust than those of the Chile Solidario Panel and show small, but clearly positive effects for several variables, especially the number of workers in the family, the percentage of workers in the famly and the employment of the head of the family.Matching, Extreme poverty, Impact evaluation, Treatment substitution, Administrative data.
Can Rational Choice Cope with Identity?
Social identity poses one of the most important challenges to rational choice theory, but rational
choice theorists do not hold a common position regarding identity. On the one hand, externalist
rational choice ignores the concept of identity or reduces it to revealed preferences. On the other
hand, internalist rational choice considers identity as a key concept in explaining social action,
because it permits expressive motivations to be included in the models. However, internalist
theorists tend to reduce identity to desire -the desire of a person to express her social being. From an
internalist point of view, that is, from a viewpoint in which not only desires but also beliefs play a
key role in social explanations as mental entities, this paper rejects externalist reductionism and
proposes a redefinition of social identity as a net of beliefs about oneself, beliefs that are indexical,
robust and socially shaped.the First ISA Forum of Sociology. Barcelona, Spain.September 5-8, 200
Rational choice, social identity, and beliefs about oneself
Social identity poses one of the most important challenges to rational choice theory, but rational choice theorists do not hold a common position regarding identity. On one hand, externalist rational choice ignores the concept of identity or reduces it to revealed preferences. On the other hand, internalist rational choice considers identity as a key concept in explaining social action because it permits expressive motivations to be included in the models. However, internalist theorists tend to reduce identity to desire—the desire of a person to express his or her social being. From an internalist point of view, that is, from a viewpoint in which not only desires but also beliefs play a key role in social explanations as mental entities, this article rejects externalist reductionism and proposes a redefinition of social identity as a net of beliefs about oneself, beliefs that are indexical, robust, and socially shaped
Eletriptan in the management of acute migraine. An update on the evidence for efficacy, safety, and consistent response
Migraine is a multifactorial, neurological and disabling disorder, also characterized by several autonomic symptoms. Triptans, selective serotonin 5-HT1B/1D agonists, are the first-line treatment option for moderate-to-severe headache attacks. In this paper, we review the recent data on eletriptan clinical efficacy, safety, and tolerability, and potential clinically relevant interactions with other drugs. Among triptans, eletriptan shows a consistent and significant clinical efficacy and a good tolerability profile in the treatment of migraine, especially for patients with cardiovascular risk factors without coronary artery disease. It shows the most favorable clinical response, together with sumatriptan injections, zolmitriptan and rizatriptan. Additionally, eletriptan shows the most complex pharmacokinetic/dynamic profile compared with the other triptans. It is metabolized primarily by the CYP3A4 hepatic enzyme and therefore the concomitant administration of CYP3A4-potent inhibitors should be carefully evaluated. A relatively low risk of serotonin syndrome is given by the co-administration with serotoninergic drugs. No clinically relevant interaction has been found with drugs used for migraine prophylactic treatment or other acute drugs, with the exception of ergot derivatives that should not be co-administered with eletriptan
Réplica de los autores
6 páginas.-- Artículo de debate sobre: "El giro analítico en Sociología".Nuestro escrito tenía dos partes bien diferenciadas, una negativa y otra positiva. La
primera denunciaba lo que no debía ser (pero en parte es) la sociología y la segunda proponía lo que debería ser, y en parte ya es.Peer reviewe
Cadena de valor del sector turístico de la ciudad de La Plata : Identificación y comportamiento de los subsectores de servicios que la componen
El trabajo contextualiza el sector turístico de la ciudad de La Plata, dentro de las pesrpectivas coyunturales del sector a nivel global. En el Capítulo II se desarrolla el marco teórico, partiendo desde el tradicional modelo de cadena de valor de los 90, (Porter, Garralda Ruiz, Sanchez Quintero) y analizado también desde la mirada del enfoque de sistemas de valor (Porter 1999), y exponiendo en la parte final del capítulo, una metodología para el análisis de las cadenas de valor. En el Capítulo III se refiere la visión que la literatura le asigna específicamente a la Cadena de Valor del Sector Turístico, incorporándole los nuevas tendencias y conceptos que se hacen indivisibles en el análisis del sector turístico, las buenas prácticas para la Gobernanza y la visión de los destinos turísticos inteligentes, dentro del marco de los objetivos de desarrollo sustentable 2030 (ODS). El Capítulo IV describe un modelo de cadena de valor para el desarrollo sustentable del sector turístico contemplando los nuevos enfoques y tendencias y se procede a la identificación y análisis de cada uno de los subsectores de servicios que componen la cadena de valor en la Ciudad, del que surgen las reflexiones finales y recomendaciones del Capítulo V.Facultad de Ciencias Económica
Educar a través del arte abstracto, una propuesta didáctica a realizar en colaboración con el Museo de Arte Contemporáneo Esteban Vicente de Segovia
Poniendo en sintonía las actuales teorías sobre Educación Artística en las aulas y en los museos, el presente Trabajo Fin de Grado propone una serie de actividades y metodologías para educar a través del Arte Abstracto, y a realizar en colaboración con el Museo de Arte Abstracto Esteban Vicente de Segovia.
Se revisan las reciente teorías en Educación Artística, así como la evolución de los planteamientos educativos en los museos, promulgando una colaboración sinérgica y enriquecedora de ambas instituciones en el presente.
La propuesta didáctica se concreta en cinco actividades consensuadas con el Departamento de Educación del Museo de Arte Contemporáneo Esteban Vicente de Segovia.Grado en Educación Primari
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