10,021 research outputs found

    Synthesis and Characterization of Sugar Derivatives as Functional Gelators

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    Systems formed by the supramolecular assemblages of organic molecules known as organogelators and hydrogelators are currently, and only recently, a subject of great attention and promise. In this context, low molecular weight gelators (LMWGs) are of particular interest because they provide a bottom-up approach to the formation of supramolecular architectures through self-assembly. Gelator molecules do so via the initial formation of a one-dimensional array of individual molecules bound non-covalently through forces such as: hydrogen bonds, electrostatic forces, Van der Waals interactions, and other weak forces such as π-π interactions. These interactions then lead to secondary structure formation through a similar assembly mechanism. Understanding the gelation process through characterization techniques is critical to the development of a design rationale for gelator molecules. Past and current research performed by the Wang group indicates that analogues of various 4,6-benzylidene acetals form stable gels in organic, aqueous, and organic/aqueous solvents at varying concentrations. The basis of varying the 4,6-protecting groups on glucose and glucosamine derivatives is to discern the relative structure activity relationships of these systems, and as well to fabricate functional systems which respond to external stimulus. Stimuli responsive or trigger release gel systems formed by sugar based low molecular weight gelators (LMWGs) have applications as smart biocompatible materials, and such responsiveness in various media was explored and developed to determine the feasibility of such applications using monosaccharide derivatives

    Construction productivity analysis for asphalt concrete pavement rehabilitation in urban corridors

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    The results of a constructibility and productivity analysis for the California Department of Transportation Long Life Asphalt Concrete Pavement Rehabilitation Strategies program are presented. With the assistance of California asphalt concrete (AC) paving contractors, the analysis explored the effects on construction productivity of rehabilitation materials, design strategy (crack seat and overlay, full-depth replacement), layer profiles, AC cooling time, resource constraints, and alternative lane closure tactics. Deterministic and stochastic analysis programs were developed. A sensitivity study that examined the construction production capability within a 55-h weekend closure was performed. Weekend closures were also compared with continuous closures. Demolition and AC delivery truck flows were the major constraints limiting the AC rehabilitation production capability. It was concluded from the study that efficient lane closure tactics designed to work with the pavement profile (an minimize the nonworking time to increase the construction product! on efficiency. The results of the study will help road agencies evaluate rehabilitation strategies and tactics with the goal of balancing the maximization of production capability and minimization of traffic delay during urban pavement rehabilitation.open114sciescopu

    Cadre conceptuel pour dĂ©finir la population statistique de l’économie sociale au QuĂ©bec

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    Sous la direction de Marie J. BouchardL’objectif du cadre conceptuel est de fournir des concepts et des dĂ©finitions pour guider la collecte de donnĂ©es et la production de statistiques cohĂ©rentes et comparables sur l’économie sociale quĂ©bĂ©coise. L’objectif est aussi de contribuer au dĂ©veloppement de la recherche analytique sur l’économie sociale en identifiant des indicateurs pertinents pour la dĂ©crire quantitativement. Le cadre conceptuel doit ĂȘtre Ă  la fois assez gĂ©nĂ©ral pour tĂ©moigner de l’appartenance de l’économie sociale Ă  un mouvement international, et assez particulier pour bien reflĂ©ter son originalitĂ© quĂ©bĂ©coise. Dans ce document, nous employons le terme Ă©conomie sociale dans une dĂ©finition large et inclusive, couvrant les domaines de l’économie sociale coopĂ©rative, mutualiste et sans but lucratif ainsi que l’action communautaire et l’action communautaire autonome, tels que gĂ©nĂ©ralement reconnus au QuĂ©bec. Le point de dĂ©part de la conceptualisation d’une dĂ©finition « statistique » de l’économie sociale est la DĂ©finition de l’économie sociale adoptĂ©e au QuĂ©bec en 1996. Cette dĂ©finition, Ă  l’instar d’autres dĂ©finitions employĂ©es ailleurs dans le monde, montre la primautĂ© de la finalitĂ© sociale sur l’activitĂ© Ă©conomique. Ceci se manifeste notamment dans les traits empiriques qui sont caractĂ©ristiques des structures et du fonctionnement de l’économie sociale et qui la distinguent du reste de l’économie. Le cadre conceptuel qui en dĂ©coule Ă©tablit le type d’entitĂ©s, les statuts juridiques, les secteurs d’activitĂ©s exclus et un faisceau de critĂšres de qualification des organisations de l’économie sociale. Il Ă©tablit aussi une typologie des organisations. Le cadre conceptuel permet Ă©galement d’évaluer les composantes pĂ©riphĂ©riques du champ et de prĂ©voir sa propre Ă©volution (par ex. pour l’intĂ©gration de nouvelles organisations qui seraient reconnues d’économie sociale). Les entitĂ©s de l’économie sociale sont des entreprises (au sens de Statistique Canada) ayant les statuts juridiques de coopĂ©ratives, mutuelles, ou d’organismes sans but lucratif (OSBL). Le terme « entreprise » n’étant pas utilisĂ© dans tous les milieux de l’économie sociale, nous employons le terme « organisations d’économie sociale » de maniĂšre Ă  toutes les englober. Les secteurs du SystĂšme de comptabilitĂ© nationale du Canada (SCNC) les plus susceptibles Ă  contenir des organisations d’économie sociale sont le secteur des sociĂ©tĂ©s non financiĂšres, celui des sociĂ©tĂ©s financiĂšres et celui des institutions sans but lucratif au service des mĂ©nages. Il est peu probable de trouver des organisations d’économie sociale dans les autres secteurs Ă©conomiques du SCNC, Ă  savoir le secteur de l’administration publique, celui des mĂ©nages, certaines parties du secteur des institutions du secteur public au service des mĂ©nages et le secteur des entreprises non constituĂ©es en sociĂ©tĂ©s. Certains secteurs d’activitĂ© du SystĂšme de classification des industries de l’AmĂ©rique du Nord (SCIAN) ne font pas partie de l’économie sociale : les organismes religieux, les regroupements patronaux, les regroupements professionnels, les syndicats et les partis politiques. Des critĂšres permettent de qualifier les organisations qui font partie de l’économie sociale (et leurs filiales respectives) : la gouvernance dĂ©mocratique; la distribution limitĂ©e ou interdite des excĂ©dents ; l’autonomie et l’indĂ©pendance ; et la production organisĂ©e de biens ou de services. Un seul de ces traits ne suffit pas pour caractĂ©riser l’économie sociale, et ces traits ne sont pas hiĂ©rarchisĂ©s entre eux. C’est plutĂŽt un ensemble de traits, ou un « faisceau de critĂšres », qui doit ĂȘtre observĂ© pour qualifier l’économie sociale. L’opĂ©rationnalisation de ces critĂšres se fait par tris successifs, du plus simple au plus exigeant sur le plan mĂ©thodologique, de maniĂšre Ă  filtrer progressivement la population statistique de l’économie sociale. Au QuĂ©bec, les statuts juridiques de la coopĂ©rative et de la mutuelle couvrent l’ensemble des critĂšres du cadre conceptuel et permettent d’emblĂ©e de classer ces organisations dans le champ. Les organisations ayant un statut juridique d’organisme sans but lucratif rencontrent le critĂšre de distribution limitĂ©e ou interdite des excĂ©dents, mais doivent ĂȘtre examinĂ©es pour Ă©tablir (successivement, cette fois) qu’ils correspondent aux critĂšres de : a) production organisĂ©e de biens ou de services ; b) autonomie et indĂ©pendance et c) gouvernance dĂ©mocratique. Ainsi, puisque les organismes sans but lucratif peuvent ĂȘtre mis sur pied pour de multiples fins, seuls ceux qui produisent de maniĂšre organisĂ©e des biens ou des services font partie de l’économie sociale. Étant donnĂ© que les OSBL peuvent ĂȘtre contrĂŽlĂ©s par des personnes ou des entitĂ©s qui n’en sont pas les membres, seuls ceux qui sont exempts de contrĂŽle externe font partie de l’économie sociale. Enfin, puisque OSBL n’ont pas d’obligation lĂ©gale en matiĂšre d’inspection, seuls ceux qui peuvent tĂ©moigner du fonctionnement de leurs instances de gouvernance dĂ©mocratique font partie de l’économie sociale. Le cadre conceptuel sert aussi Ă  dĂ©velopper une typologie qui vise Ă  rendre compte de dynamiques Ă©conomiques diffĂ©renciĂ©es des organisations d’économie sociale. Se basant sur la capacitĂ© d’hybridation des ressources qui caractĂ©rise l’économie sociale, la typologie Ă©tablit six grands types d’organisations de l’économie sociale suivant le mode dominant d’allocation des ressources (Ă©change marchand, redistribution ou rĂ©ciprocitĂ©) et leur principale provenance (de source privĂ©e ou publique). Cette typologie n’est certes pas suffisante pour classer les entitĂ©s de la population, mais elle est complĂ©mentaire Ă  d’autres classifications existantes1. L’adaptation du cadre conceptuel aux particularitĂ©s quĂ©bĂ©coises de l’économie sociale permet de tenir compte des entitĂ©s qui, aux vues du cadre conceptuel, paraissent ĂȘtre des « exceptions » puisqu’elles ne correspondent pas aux critĂšres du modĂšle logique, mais appartiennent nĂ©anmoins au « mouvement » de l’économie sociale du QuĂ©bec. Quelques‐uns de ces cas sont analysĂ©s en dĂ©tail et sont intĂ©grĂ©s dans le ModĂšle logique opĂ©rationnel de l’économie sociale au QuĂ©bec en 2011, qui reprend les Ă©tapes du cadre gĂ©nĂ©ral et tient compte des particularitĂ©s quĂ©bĂ©coises. Enfin, une analyse du cas des fondations permet de voir les caractĂ©ristiques de celles qui seraient le plus susceptibles d’ĂȘtre reconnues comme faisant partie de l’économie sociale si la dĂ©finition quĂ©bĂ©coise venait Ă  les inclure. Ce type d’analyse peut ĂȘtre repris pour d’autres organisations ou secteurs d’activitĂ©s, dans le contexte oĂč le cadre conceptuel viendrait Ă  Ă©voluer.The objective of the conceptual framework is to supply concepts and definitions to guide the data collection and the production of statistics which are coherent and comparable regarding QuĂ©bec’s social economy. The objective is also to contribute to the development of analytical research on social economy by identifying relevant indicators to quantitatively describe it. The conceptual framework must be quite general to establish the fact that the social economy is part of an international movement and at the same time specific enough to properly reflect its QuĂ©bec originality. In this document, we will use the term “social economy” in a large and inclusive definition, which will cover the fields of cooperative, mutual and non‐profit social economy, as well as community action and autonomous community action as generally acknowledged in QuĂ©bec. The starting point of the conceptualization of the “statistical” definition of social economy is the Definition of Social Economy adopted in QuĂ©bec in 1996. Like other definitions used elsewhere in the world, this definition underlines the primacy of social purpose over economic activity. This is especially shown in the empirical features which are typical of the structures and operation of the social economy and which distinguish it from the rest of the economy. The resulting conceptual framework establishes the type of entities, the legal status, sectors of activity which are excluded and a cluster of qualification criteria of social economy organizations. It also establishes a typology of organizations. The conceptual framework also allows assessing the peripheral components in this field and forecasting its own progress (for example, for the integration of new organizations which would be acknowledged as being part of the social economy). Social economy entities are enterprises (within the meaning given by Statistics Canada) which have legal status as cooperative, mutuals or non‐profit organizations (NPOs). Because the term “enterprise” is not used in all sectors of the social economy, we will use the term “social economy organizations” so as to include all of them. The sectors of the Canadian System of National Accounts (CSNA) which are the most likely to include social economy organizations are those of non‐financial corporations, financial corporations and non‐profit institutions serving households. It is highly improbable that social economy organizations will be found in other CSNA economic sectors, that is, the sectors of government, households, some parts of the government institutions serving households sector and the unincorporated business sector. Some sectors of activity of the North American Industry Classification System (NAICS) are not part of the social economy. These are religious organizations, employers’ associations, professional associations, trade unions and political parties. Some criteria allow qualifying organizations which are part of the social economy (and their respective subsidiaries): democratic governance; restricted or prohibited distribution of surplus; autonomy and independence; and the organized production of goods or services. Only one criterion is insufficient to characterize the social economy and there is no hierarchy of criteria. Instead, it is a series of features or a “cluster of features” which must be noted to qualify the social economy. The operationalization of these criteria is done through successive triage from the simplest to the most demanding from a methodological point of view, so as to progressively filter the statistical population of the social economy. In QuĂ©bec, the legal status of the cooperative and mutual cover all of the criteria of the conceptual framework and allow classifying these organizations in this field. Organizations that have legal status as non‐profit organizations meet the criterion of limited or prohibited distribution of surplus, but they must be examined to determine (successively this time) if they correspond to the criteria of: a) organized production of goods or services; b) autonomy and independence; and c) democratic governance. Accordingly, because non‐profit organizations may be established for many purposes, only those which produce goods or services in an organized manner are part of the social economy. Considering that non‐profit organizations may be controlled by persons or entities which are not part of their membership, only those organizations which are not externally controlled are part of the social economy. Finally, because non‐profit organizations have no legal requirement regarding inspection, only those which may attest to the operation of their democratic processes of governance are part of the social economy. The conceptual framework is also used to create a typology, the purpose of which is to account for the differentiated economic dynamics of social economy organizations. Based on the capacity for hybridization of the resources which characterizes the social economy, the typology establishes six major types of organizations of the social economy according to the dominant mode of allocation of resources (commercial exchange, redistribution or reciprocity) and their main source (private or public). This typology is certainly insufficient to classify entities within the population but it is a complement to other existing classifications2. Adapting the conceptual framework to the specifics of QuĂ©bec’s social economy allows taking into consideration entities which seem to be “exceptions” as far as the conceptual framework is concerned, because they do not correspond to the criteria of the logical model but nevertheless belong to the social economy “movement” of QuĂ©bec. Some of these cases are analyzed in detail and are integrated to the ModĂšle logique opĂ©rationnel de l’économie sociale au QuĂ©bec en 2011 [Logical Operational Model of the Social Economy in QuĂ©bec in 2011], which repeats the steps of the general framework and takes the specifics of QuĂ©bec into consideration. Finally, a case analysis of foundations shows the characteristics of those which would most likely be acknowledged as being part of the social economy if the QuĂ©bec definition would eventually include them. If the conceptual framework should progress, this type of analysis may be repeated for other organizations or sectors of activity.Le cadre conceptuel pour dĂ©finir la population statistique de l’économie sociale au QuĂ©bec rĂ©sulte d’une Ă©tude commandĂ©e par l’Institut de la statistique du QuĂ©bec (ISQ), le ministĂšre de l’Emploi et de la SolidaritĂ© sociale (MESS), le ministĂšre de la SantĂ© et des Services sociaux (MSSS) et le SecrĂ©tariat Ă  l’action communautaire autonome et aux initiatives sociales (SACAIS). Le mandat a Ă©tĂ© confiĂ© Ă  la Chaire de recherche du Canada en Ă©conomie sociale de l’UQAM suite Ă  un avis aux chercheurs se clĂŽturant le 26 aoĂ»t 2010

    Temptations, techniques and typologies: Insights from a Western Australian sample of young people who burgle

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    A significant amount of property crime is committed by young people. In this novel qualitative study, 50 young people were interviewed to obtain an insight into their motivations to burgle. Decisions were based on peer pressure, opportunity and perceived need. Bennett and Wright’s typologies of adult burglars were applied to young burglars. Young burglars were more prone than adults in Bennett and Wright’s study to commit opportunistic burglaries, but were deterred by similar target characteristics. The social and psychological factors are strong motivators for youth burglary and should guide the development of intervention and deterrence strategies

    Congestion delays at hub airports

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    Cover titleJune 1986Includes bibliographical references (p. 146)A deterministic model was developed to study the effects of inefficient scheduling on flight delays at hub airports. The model bases the delay calculation on published schedule data and on user-defined airport capacities. Data from the Official Airline Guide of May, 1977 and May, 1985 was used for the analysis. Twelve large airports were studied in the hopes of finding a correlation between airport delay due to congestion and hubs. Data for both time periods was analyzed for the twelve airports in order to find historical trends in the growth of hubbing. Among the airports studied, those that were hubs had significantly more delays due to inefficient scheduling than the non-hubs, even for an equivalent number of operations. Also, these relative inefficiencies were shown to exist from hub to hub. Delays at hubs of similar size differed by up to 200 percent

    Environmental enteric dysfunction and the fecal microbiota in malawian children

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    Environmental enteric dysfunction (EED) is often measured with a dual sugar absorption test and implicated as a causative factor in childhood stunting. Disturbances in the gut microbiota are hypothesized to be a mechanism by which EED is exacerbated, although this supposition lacks support. We performed 16S ribosomal RNA gene sequencing of fecal samples from 81 rural Malawian children with varying degrees of EED to determine which bacterial taxa were associated with EED. At the phyla level, Proteobacteria abundance is reduced with severe EED. Among bacterial genera, Megasphaera, Mitsuokella, and Sutterella were higher in EED and Succinivibrio, Klebsiella, and Clostridium_XI were lower in EED. Bacterial diversity did not vary with the extent of EED. Though EED is a condition that is typically believed to affect the proximal small bowel, and our focus was on stool, our data do suggest that there are intraluminal microbial differences that reflect, or plausibly lead to, EED
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