24,353 research outputs found
Electronic charge density in helium in the first order shielding approximation
Electronic charge density for ground state of helium as function of nuclear charg
Some Remarks on the Use of the Variational Principle for the Second Order Energy
Approximate ground state wave function used in variational principle for second order energ
Leave No Youth Behind: Opportunities for Congress to Reach Disconnected Youth
This report discusses six programs being considered by the 108th Congress for reauthorization, focusing on policies designed to assist disconnected and at-risk youth. The review seeks to identify how the programs do or do not consider at-risk or disconnected youth ad how such programs might be improved. After an introduction by Alan Houseman, six papers include: "The Adult Education and Family Literacy Act and Disconnected Youth" (Cynthia G. Brown and Andy Hartman); "The Higher Education Act and Disconnected Youth" (Thomas R. Wolanin); "The Individuals with Disabilities Education Act and Disconnected Youth" (Cynthia G Brown and Jennifer Mezey); "The Runaway and Homeless Youth Act and Disconnected Youth" (Bob Reeg); "The Temporary Assistance for Needy Families Program and Disconnected Youth" (Jodie Levin-Epstein); and "The Workforce Investment Act and Disconnected Youth" (Nisha Patel and Steve Savner)
Yet Another Poincare's Polyhedron Theorem
Poincar\'e's Polyhedron Theorem is a widely known valuable tool in
constructing manifolds endowed with a prescribed geometric structure. It is one
of the few criteria providing discreteness of groups of isometries. This work
contains a version of Poincar\'e's Polyhedron Theorem that is applicable to
constructing fibre bundles over surfaces and also suits geometries of
nonconstant curvature. Most conditions of the theorem, being as local as
possible, are easy to verify in practice.Comment: 9 pages, 2 figures, 5 references. Final versio
Lower bounds for several online variants of bin packing
We consider several previously studied online variants of bin packing and
prove new and improved lower bounds on the asymptotic competitive ratios for
them. For that, we use a method of fully adaptive constructions. In particular,
we improve the lower bound for the asymptotic competitive ratio of online
square packing significantly, raising it from roughly 1.68 to above 1.75.Comment: WAOA 201
Health needs of the Roma population in the Czech and Slovak Republics.
In the growing literature on the human rights of Roma people in Central Europe, their relatively poor health status is often mentioned. However, little concrete information exists about the contemporary health status of the Roma in this region. We sought information on the health of the Roma in two of countries with significant Roma minorities, the Czech and Slovak Republics, by means of systematic searches for literature on the health of Roma people published in Czech or Slovak or by authors from the two countries. Published research on health of the Roma population is sparse. The topics that have received attention suggest a focus on concepts of contagion or social Darwinism, indicating a greater concern with the health needs of the majority populations with which they live. What limited evidence exists indicates that the health needs of the Roma population are considerable. With very few exceptions, the health status of Roma is worse than that of non-Roma population in both countries. The burden of communicable disease among Roma is high and diseases associated with poor hygiene seem to be particularly important. Evidence on health care suggests poor communication between Roma and health workers and low uptake of preventative care. The health needs of Roma lack visibility, not only because of the absence of research but also the absence of advocacy on their behalf. Since 1989, Czech and Slovak researchers have largely turned away from health research on particular ethnic groups. This probably reflects a growing sensitivity about stigmatising Roma, but it also makes it difficult to know how their circumstances might be improved. There is a need for further research into the health of Roma people with particular emphasis on non-communicable disease and for interventions that would improve their health
Photovoltaic effect in ferroelectric ceramics
The ceramic structure was simulated in a form that is more tractable to correlation between experiment and theory. Single crystals (of barium titanate) were fabricated in a simple corrugated structure in which the pedestals of the corrugation simulated the grain while the intervening cuts could be filled with materials simulating the grain boundaries. The observed photovoltages were extremely small (100 mv)
Recientes tendencias en la teoría de la educación comparada
Antes de realizar la descripción de las actuales tendencias en la teoría de la Educación Comparada, se recuerdan las etapas a través de las cuales ha llegado a su estado actual. De esta manera se mencionan los periodos que Kazamias, Bereday, Noah y Eckstein han indicado en el desarrollo de la Educación Comparada, concluyendo con las que han indicado Kelly y Altbach. El autor no se muestra conforme con esta costumbre de diferenciar etapas pues cree que la evolución de la Educación Comparada ha sido efecto, más de unas doctrinas epistemológicas concretas que de unos movimientos globales. A continuación describe las tres principales de estas doctrinas, que han marcado unas tendencias en el modo de concebir y realizar la Educación Comparada. 1ª El pensamiento neopositivista busca una explicación funcional de la realidad, tratando de descubrir las leyes que explican sus fenómenos. Durkheim aplico este modo de ver a la Sociología, y Anderson lo ha hecho a la Educación Comparada. Se trata de aislar distintas variables y de descubrir las relaciones constantes que unen unas a otras. Dentro de esta línea Anderson utiliza el método hologeístico, que mide las variables teóricas en amplias muestras (de alcance mundial) de culturas humanas. Se puede aplicar este método también a la educación, como ha hecho Zern, defendiendo la idea de que la buena educación supone exigir al niño un esfuerzo y una sumisión disciplinada, lo cua1 mejora su socialización y su rendimiento intelectual. La investigación hologeística ha sido poco explotada y, si se superan las dificultades metodológicas que le son propias, promete llegar a ser el instrumento positivista más importante en Educación Comparada. 2ª E1 neomarxismo se halla presente también en los enfoques de la Educación Comparada, aportando las mismas ideas que va repitiendo en todas partes: que en los países capitalistas la educación está dirigida por una minoría privilegiada que busca, a través de ella, establecer la división de clases y explotar a los trabajadores. El principal representante de esta tendencia es Carnoy; algunos, como Wallert, pretenden que los análisis han de hacerse a nivel no nacional, sino mundial. 3º El neorrelativismo está representado por Brian Holmes. Desconfiando del concepto de medición absoluta y de la validez incondicional de leyes generales, y afirmando la relatividad de las Ciencias Naturales, se pretende una mera aproximación al "problema". Según esto, las Ciencias Sociales y la Educación Comparada han de abandonar la investigación pura y realizar una búsqueda de generalizaciones contextuales que ayuden a resolver los problemas prácticos. También están en esta línea los autores pertenecientes a la "nueva Sociología de la Educación" y a la etnometodología. Una realidad que esta tendencia no puede explicar son ciertas necesidades y exigencias humanas que revelan una tendencia invariable y universal, en lo más profundo de la persona humana.Before carrying out the description of the actual tendencies in the theory of Comparative Education the steps by which it has arrived at its present state should be remembered. The periods that Kazamias, Bereday, Noah and Eckstein have pointed out in the development of Comparative Education are mentioned concluding with those suggested by Kelly and Altbach. The author does not agree with this custom of distinguishing phases, he thinks that the evolution of Comparative Education has been effected more by concrete epistemological doctrines which have effected some tendencies in the way of conceiving and putting Comparative Education into effect. 1 Neopositivism looks for a functional explanation of reality, trying to discover the laws which explain its phenomenons. Durkheim applied this view to Sociology and Anderson has done so to Comparative Education. He tries to isolate distinct variables and to discover the constant relations that unite some to others. Within this framework Anderson utilises the hologeistic method which measures theoretical variables in worldwide samples of human cultures. This method can also be applied to education, as Zern has done, defending the idea that a good education requires the obedience and discipline of the child, which should improve its socialization and intellectual achievement. Hologeistic research has barely been tapped. If the methodological difficulties inherent in the approah can be overcome it promises to become the most important tool in Comparative Education. 2 Neomarxism is also an approach to Comparative Education with the same ideas that are being repeated everywhere: that in capitalist countries education is controlled by a privileged minority who seek by means of it to establish the division of classes and exploit the workers. The principal exponent of this theory is Carnoy; others like Wallert state that analysis has to be made at a national level. 3. Neorelativzsm is represented by B. Holmes. Distrusting the concept of absolute measurement and the unconditional validity of general laws and affirming the relationship of the Natural Sciences, it achieves a mere approximation to the problem. According to this the Social Sciences and Comparative Education have to give up pure research and carry out a search for contextual generalisations that would help to resolve the practical problems. The authorities of the new Sociology of education and tnomethodology are also following this line. This trend is not able to explain certain human necessities and requirements which reveal an invariable and universal tendency at the deepest leve
Computer methods for the reduction, correlation and analysis of space battery test data, phase 2, part 1 Final report, 1 Nov. - 31 Dec. 1967
Computer methods for reduction, correlation, and analysis of space battery test dat
Magnetic resonance imaging of myocardial strain after acute ST-segment-elevation myocardial infarction: a systematic review
The purpose of this systematic review is to provide a clinically relevant, disease-based perspective on myocardial strain imaging in patients with acute myocardial infarction or stable ischemic heart disease. Cardiac magnetic resonance imaging uniquely integrates myocardial function with pathology. Therefore, this review focuses on strain imaging with cardiac magnetic resonance. We have specifically considered the relationships between left ventricular (LV) strain, infarct pathologies, and their associations with prognosis. A comprehensive literature review was conducted in accordance with the PRISMA guidelines. Publications were identified that (1) described the relationship between strain and infarct pathologies, (2) assessed the relationship between strain and subsequent LV outcomes, and (3) assessed the relationship between strain and health outcomes. In patients with acute myocardial infarction, circumferential strain predicts the recovery of LV systolic function in the longer term. The prognostic value of longitudinal strain is less certain. Strain differentiates between infarcted versus noninfarcted myocardium, even in patients with stable ischemic heart disease with preserved LV ejection fraction. Strain recovery is impaired in infarcted segments with intramyocardial hemorrhage or microvascular obstruction. There are practical limitations to measuring strain with cardiac magnetic resonance in the acute setting, and knowledge gaps, including the lack of data showing incremental value in clinical practice. Critically, studies of cardiac magnetic resonance strain imaging in patients with ischemic heart disease have been limited by sample size and design. Strain imaging has potential as a tool to assess for early or subclinical changes in LV function, and strain is now being included as a surrogate measure of outcome in therapeutic trials
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