Elementary computer-mediated online distance education : identification of criteria for successful implementation and practice

This study had three purposes related to the effective implem,entation and practice of computer-mediated online distance education (C-MODE) at the elementary level: (a) To identify a preliminary framework of criteria 'or guidelines for effective implementation and practice, (b) to identify areas ofC-MODE for which criteria or guidelines of effectiveness have not yet been developed, and (c) to develop an implementation and practice criteria questionnaire based on a review of the distance education literature, and to use the questionnaire in an exploratory survey of elementary C-MODE practitioners. Using the survey instrument, the beliefs and attitudes of 16 elementary C'- MODE practitioners about what constitutes effective implementation and practice principles were investigated. Respondents, who included both administrators and instructors, provided information about themselves and the program in which they worked. They rated 101 individual criteria statenlents on a 5 point Likert scale with a \. point range that included the values: 1 (Strongly Disagree), 2 (Disagree), 3 (Neutral or Undecided), 4 (Agree), 5 (Strongly Agree). Respondents also provided qualitative data by commenting on the individual statements, or suggesting other statements they considered important. Eighty-two different statements or guidelines related to the successful implementation and practice of computer-mediated online education at the elementary level were endorsed. Response to a small number of statements differed significantly by gender and years of experience. A new area for investigation, namely, the role ofparents, which has received little attention in the online distance education literature, emerged from the findings. The study also identified a number of other areas within an elementary context where additional research is necessary. These included: (a) differences in the factors that determine learning in a distance education setting and traditional settings, (b) elementary students' ability to function in an online setting, (c) the role and workload of instructors, (d) the importance of effective, timely communication with students and parents, and (e) the use of a variety of media.

The versatility and utilization of phosphorus based compounds in classic carbon-carbon bond forming and esterification reactions

The phosphonium salt room temperature ionic liquid tetradecyltrihexylphosphonium chloride (THPC) has been employed as an efficient reusable media for the palladium catalyzed Suzuki cross-coupling reaction of aryl halides, including aryl chlorides, under mild conditions. The cross-coupling reactions were found to proceed in THPC containing small amounts ofwater and toluene (single phase) using potassium phosphate and 1% Pd2(dba)3'CHCI3. Variously substituted iodobenzenes, including electron rich derivatives, reacted efficiently in THPC with a variety of arylboronic acids and were all complete within 1 hour at 50°C. The corresponding aryl bromides also reacted under these conditions with the addition of a catalytic amount of triphenylphosphine that allowed for complete conversion and high isolated yields. The reactions involving aryl chlorides were considerably slower, although the addition of triphenylphosphine and heating at 70°C allowed high conversion of electron deficient derivatives. Addition of water and hexane to the reaction products results in a triphasic system, from which the catalyst was then recycled by removing the top (hexanes) and bottom (aqueous) layers and adding the reagents to the ionic liquid which was heated again at 50°C; resulting in complete turnover of iodobenzene. Repetition of this procedure gave the biphenyl product in 82-97% yield (repeated five times) for both the initial and recycled reaction sequences. IL ESTERIFICATIONREACTION A new class oftrialkylphosphorane has been prepared through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence oftriethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a subtle interplay involving basicity of the reaction media, solvent, and tuning the electronic and steric nature of the carboxylic acid and stenc nature of the phosphorane employed. A coherent mechanism is postulated to explain these observations involving reaction via an initial acyloxyphosphonium ion.

Quand _Refus global_ devient "Refus global" : l'histoire d'une réception partielle

Refus global, le recueil, n’est pas « Refus global », le texte rédigé par Paul-Émile Borduas et cosigné par 15 membres du groupe automatiste. Partant de cette distinction entre le recueil automatiste et son texte éponyme et du constat selon lequel la partie éclipse le tout dans le discours critique, cette thèse a pour objectif d’expliquer l’occultation du recueil dans l’histoire sociale et artistique québécoise. À partir de l’étude de la réception de 1948 à 2008, j’interroge la constitution du récit commun entourant l’œuvre, duquel le recueil est exclu. Il s’agit donc de mettre au jour les obstacles qui se sont présentés dans le parcours de réception du recueil, nuisant à la formation d’un discours unifié et cohérent à son sujet et l’empêchant de s’inscrire dans l’histoire. Dégagés de l’étude du corpus composé de 639 objets sémiotiques secondaires (OSS, selon le concept proposé par Brigitte Louichon), les obstacles à la réception du recueil relèvent à la fois de facteurs pragmatiques, telles la composition hétérogène de l’œuvre ou sa disponibilité; de facteurs institutionnels ou historiographiques, comme la disciplinarisation du champ culturel ou l’impact du récit de la Révolution tranquille sur l’histoire littéraire; et de facteurs humains, reposant sur le rôle des auteurs et de certains critiques dans l’accueil réservé à l’œuvre. Les différentes étapes de la réception sont ainsi considérées : de l’horizon d’attente (Jauss) à la réception productive (Link), en passant par la publication, les premières critiques, les rééditions, les lectures savantes, l’historicisation et l’entrée de l’œuvre dans la mémoire à titre de symbole ou d’hypotexte. Or, plutôt qu’à ce parcours de réception exemplaire, c’est son envers qui est interrogé ici, c’est-à-dire les difficultés et les déviations de la réception du recueil Refus global. Cette thèse est divisée en trois parties. La première, théorique et méthodologique, situe mon propos dans les domaines de l’histoire culturelle et des études de réception, et présente diverses considérations concernant la constitution du corpus et le traitement des données. La deuxième aborde l’horizon d’attente et la première réception, moment crucial pour la survie de l’œuvre, comme l’ont montré Hans Robert Jauss et Daniel Chartier. On y observe notamment l’effet de verrou (Cambron) qu’a le renvoi de Borduas sur la constitution du récit de réception, de même que les critères éthiques et esthétiques en fonction desquels s’est opérée la hiérarchisation des composantes du recueil. La troisième partie couvre la réception subséquente (1950-2008). À l’étude des obstacles empêchant l’intégration du recueil dans l’histoire s’ajoute alors l’étude des réceptions parallèles, parcellaires et autonomes dont a bénéficié Refus global pour survivre – ponctuellement et partiellement – en dehors du récit commun formé autour de « Refus global ». Avec les différentes catégories d’OSS (directs, indirects, hypertextuels, métacritiques et parcellaires), ces trois types de réception font partie des outils heuristiques développés dans le but d’expliquer la réception partielle dont a fait l’objet le recueil. Selon l’approche quantitative et environnementaliste de l’histoire culturelle, Refus global est envisagé comme un microcosme de la culture, dans lequel certaines œuvres sont retenues et d’autres négligées. L’analyse d’un corpus critique large et varié permet ainsi de saisir non seulement les phénomènes conduisant à la consécration du texte éponyme ou à l’oubli relatif du recueil, mais aussi les tendances critiques, les parutions marginales, les critiques isolées, etc. qui, enfouies dans les angles morts de la réception, offrent au recueil et à ses composantes des voies de contournement du discours dominant. En somme, l’étude de la réception du recueil Refus global a permis à la fois de déplacer la focalisation critique depuis « Refus global » vers Refus global, de développer des outils pour envisager la réception d’œuvres marginalisées et de mettre en évidence des critères privilégiés dans la constitution de l’histoire et de la mémoire culturelles québécoises depuis 1948.

Mortalidad en pacientes de 65 o más años, en los primeros 3 meses posfractura de cadera de origen traumático

Tercera parte de personas de 65 años o mayores caen anualmente con consecuencias variables. Los riesgos de caída aumentan con la edad y los de lesiones graves con cada caída. Lesiones severas son debido a fracturas, principalmente de cadera y más del 75% no recuperan funcionalidad previa. Estudio descriptivo cohorte retrospectiva, Clínica Los Rosales, Pereira, 1 de Enero/2007 a 31 de Diciembre/2008, la clínica avaló revisión de base de datos, escogidos códigos CIE 10 relacionados con Fractura de cadera origen traumático, excluyendo accidentes de tránsito y lesiones metastásicas óseas, edad 65 o más años. Historias clínicas fueron revisadas, información recolectada acorde al Instrumento diseñado. Consolidación base de datos, procesada por la herramienta estadística SPSS 17.0 para análisis descriptivo y obtener información demográfica, y cruce de variables con variable muerte buscando relación entre resultado y mortalidad. Total 48 pacientes, 33 cumplían criterios de ingreso, 15 excluidos por no tener información del tratamiento, 4 fueron remitidos, 11 restantes sin información por historia clínica ni telefónica de sobrevida. Edad promedio 83,4 años, género femenino 60,6% y 75,8% procedían del área urbana de Pereira, comorbilidades previas predominantes enfermedades cardiovasculares, 32,8%. Mayor consumo de medicamentos previos antihipertensivos, 81,8%, el 18,2% no recibían. Intrahospitalariamente 90,9% pacientes recibieron profilaxis antitrombotica, cirugía realizada en 90,9%, en 36,7% hecha los primeros 2 días y 42,4% al 5 día habían egresado. 9,1% registro un evento previo de fractura de cadera. 81,8% sin complicación, 9,1% murieron los primeros 3 meses posfractura. No se encontró asociación entre muerte y variables: cirugía, tromboprofilaxis.

Laser Safety in higher education - Classic video!

Vintage video (1986) on laser safety, presented by Dr. Gillian Rice. This is a 37 minute video, explaining the hazards which are likely to be encountered and ways to reduce those hazards in teaching and research laboratories in higher education. Presented in 5 parts: Part 1 (1:49) Laser radiation and the body Part 2 (8:49) Classes of laser Part 3 (13:32) Safety measures Part 4 (21:32) Other risks: precautions Part 5 (31:49) Summary

Los conceptos de salud financiera, riesgo y epidemiología en los estados financieros de las compañías del sector de extracción de petróleo crudo y gas natural en Colombia

El presente proyecto tiene como objeto identificar cuáles son los conceptos de salud, enfermedad, epidemiología y riesgo aplicables a las empresas del sector de extracción de petróleo y gas natural en Colombia. Dado, el bajo nivel de predicción de los análisis financieros tradicionales y su insuficiencia, en términos de inversión y toma de decisiones a largo plazo, además de no considerar variables como el riesgo y las expectativas de futuro, surge la necesidad de abordar diferentes perspectivas y modelos integradores. Esta apreciación es pertinente dentro del sector de extracción de petróleo y gas natural, debido a la creciente inversión extranjera que ha reportado, US$2.862 millones en el 2010, cifra mayor a diez veces su valor en el año 2003. Así pues, se podrían desarrollar modelos multi-dimensional, con base en los conceptos de salud financiera, epidemiológicos y estadísticos. El termino de salud y su adopción en el sector empresarial, resulta útil y mantiene una coherencia conceptual, evidenciando una presencia de diferentes subsistemas o factores interactuantes e interconectados. Es necesario mencionar también, que un modelo multidimensional (multi-stage) debe tener en cuenta el riesgo y el análisis epidemiológico ha demostrado ser útil al momento de determinarlo e integrarlo en el sistema junto a otros conceptos, como la razón de riesgo y riesgo relativo. Esto se analizará mediante un estudio teórico-conceptual, que complementa un estudio previo, para contribuir al proyecto de finanzas corporativas de la línea de investigación en Gerencia.

New delay-dependent stability criteria for uncertain neutral systems with mixed time-varying delays and nonlinear perturbations

The problem of stability analysis for a class of neutral systems with mixed time-varying neutral, discrete and distributed delays and nonlinear parameter perturbations is addressed. By introducing a novel Lyapunov-Krasovskii functional and combining the descriptor model transformation, the Leibniz-Newton formula, some free-weighting matrices, and a suitable change of variables, new sufficient conditions are established for the stability of the considered system, which are neutral-delay-dependent, discrete-delay-range dependent, and distributeddelay-dependent. The conditions are presented in terms of linear matrix inequalities (LMIs) and can be efficiently solved using convex programming techniques. Two numerical examples are given to illustrate the efficiency of the proposed method

Estilos de vida, atitude face à disciplina de educação física, percepção de competência, clima motivacional e orientação de objectivos em alunos do 3º ciclo e secundário

Este estudo tem como objectivo analisar os estilos de vida, a atitude face à disciplina de Educação Física, percepção de competência, clima motivacional e orientação de objectivos em alunos do género masculino e feminino do 3º ciclo e secundário. Participaram no estudo 199 alunos, sendo 102 do género masculino e 97 do género feminino, com idades compreendidas entre os 14 e os 20 anos, oriundos de Escolas com Estágio Pedagógico do Mestrado em Ensino da Educação Física nos Ensinos Básico e Secundário. A escolha das turmas teve como critérios de selecção: (1) serem leccionadas por professores estagiários ou professores orientadores de estágio pedagógico e (2) pertencerem ao período de escolaridade entre o 9º e o 11º ano. Os dados foram recolhidos através de um questionário desenvolvido por Papaioannou, Milosis, Kosmidou e Tsigihis (2007) e validado para a população portuguesa por João Martins, bem como utilizado na tese de doutoramento que está a realizar na Faculdade de Motricidade Humana. A análise inferencial foi realizada através da aplicação dos testes estatísticos: T-test para amostras independentes e Teste de Correlação de Pearson. O resultado final permitiu concluir que os estilos de vida, a atitude face à disciplina de Educação Física, percepção de competência, clima motivacional e orientação de objectivos variam relativamente aos alunos do género masculino e feminino.

Unravelling the rationale of 'overgrazing' and stocking rates in the beef production systems of Central Brazil using a bi-criteria compromise programming model

In Central Brazil, the long-term, sustainability of beef cattle systems is under threat over vast tracts of farming areas, as more than half of the 50 million hectares of sown pastures are suffering from. degradation. Overgrazing practised to maintain high stocking rates is regarded as one of the main causes. High stocking rates are deliberate and crucial decisions taken by the farmers, which appear paradoxical, even irrational given the state of knowledge regarding the consequences of overgrazing. The phenomenon however appears inextricably linked with the objectives that farmers hold. In this research those objectives were elicited first and from their ranking two, 'asset value of cattle (representing cattle ownership and 'present value of economic returns', were chosen to develop an original bi-criteria Compromise Programming model to test various hypotheses postulated to explain the overgrazing behaviour. As part of the model a pasture productivity index is derived to estimate the pasture recovery cost. Different scenarios based on farmers' attitudes towards overgrazing, pasture costs and capital availability were analysed. The results of the model runs show that benefits from holding more cattle can outweigh the increased pasture recovery and maintenance costs. This result undermines the hypothesis that farmers practise overgrazing because they are unaware or uncaring caring about overgrazing costs. An appropriate approach to the problem of pasture degradation requires information on the economics,and its interplay with farmers' objectives, for a wide range of pasture recovery and maintenance methods. Seen within the context of farmers' objectives, some level of overgrazing appears rational. Advocacy of the simple 'no overgrazing' rule is an insufficient strategy to maintain the long-term sustainability of the beef production systems in Central Brazil. (C) 2004 Elsevier Ltd. All rights reserved.

Stability criteria for the contextual emergence of macrostates in neural networks

More than thirty years ago, Amari and colleagues proposed a statistical framework for identifying structurally stable macrostates of neural networks from observations of their microstates. We compare their stochastic stability criterion with a deterministic stability criterion based on the ergodic theory of dynamical systems, recently proposed for the scheme of contextual emergence and applied to particular inter-level relations in neuroscience. Stochastic and deterministic stability criteria for macrostates rely on macro-level contexts, which make them sensitive to differences between different macro-levels.

A fuzzy multi-criteria decision approach for enhanced auto-tracking of seismic events

The main activity carried out by the geophysicist when interpreting seismic data, in terms of both importance and time spent is tracking (or picking) seismic events. in practice, this activity turns out to be rather challenging, particularly when the targeted event is interrupted by discontinuities such as geological faults or exhibits lateral changes in seismic character. In recent years, several automated schemes, known as auto-trackers, have been developed to assist the interpreter in this tedious and time-consuming task. The automatic tracking tool available in modem interpretation software packages often employs artificial neural networks (ANN's) to identify seismic picks belonging to target events through a pattern recognition process. The ability of ANNs to track horizons across discontinuities largely depends on how reliably data patterns characterise these horizons. While seismic attributes are commonly used to characterise amplitude peaks forming a seismic horizon, some researchers in the field claim that inherent seismic information is lost in the attribute extraction process and advocate instead the use of raw data (amplitude samples). This paper investigates the performance of ANNs using either characterisation methods, and demonstrates how the complementarity of both seismic attributes and raw data can be exploited in conjunction with other geological information in a fuzzy inference system (FIS) to achieve an enhanced auto-tracking performance.

Field manual 3-24 and the heritage of counterinsurgency theory

The Counterinsurgency Manual FM 3-24 has been accused of being over-dependent on the counterinsurgency 'classics' Galula and Thompson. But comparison reveals that it is different in spirit. Galula and Thompson seek practical control; the Manual seeks to build 'legitimacy'. Its concept of legitimacy is superficially Weberian, but owes more to the writings of the American Max Manwaring. The Manual presupposes that a rights-based legal order can (other things being equal) be made to be cross-culturally attractive; 'effective governance' by itself can build legitimacy. The fusion of its methods with an ideology creates unrealistic criteria for success. Its weaknesses suggest a level of incapacity to think politically that will, in time, result in further failures.

On the existence of two-dimensional Euler flows satisfying energy-Casimir stability criteria

The energy-Casimir stability method, also known as the Arnold stability method, has been widely used in fluid dynamical applications to derive sufficient conditions for nonlinear stability. The most commonly studied system is two-dimensional Euler flow. It is shown that the set of two-dimensional Euler flows satisfying the energy-Casimir stability criteria is empty for two important cases: (i) domains having the topology of the sphere, and (ii) simply-connected bounded domains with zero net vorticity. The results apply to both the first and the second of Arnold’s stability theorems. In the spirit of Andrews’ theorem, this puts a further limitation on the applicability of the method. © 2000 American Institute of Physics.