17 resultados para Supply route

em Brock University, Canada


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BACKGROUND: Capillaries function to provide a surface area for nutrient and waste exchange with cells. The capillary supply of skeletal muscle is highly organized, and therefore, represents an excellent choice to study factors regulating diffusion. Muscle is comprised of three specific fibre types, each with specific contractile and metabolic characteristics, which influence the capillary supply of a given muscle; in addition, both environmental and genetic factors influence the capillary supply, including aging, physical training, and various disease processes. OBJECTIVE: The present study was undertaken to develop and assess the functionality of a data base, from which virtual experiments can be conducted on the capillary supply of human muscle, and the adaptations of the capillary bed in muscle to various perturbations. METHODS: To create the database, an extensive search of the literature was conducted using various search engines, and the three key words - "capillary, muscle, and human". This search yielded 169 papers from which the data for the 46 variables on the capillary supply and fibre characteristics of muscle were extracted for inclusion in the database. A series of statistical analyses (ANOVA) were done on the capillary database to examine differences in skeletal muscle capillarization and fibre characteristics between young and old individuals, between healthy and diseased individuals, and between untrained, endurance trained, endurance welltrained, and resistance trained individuals, using SAS. RESULTS: There was a significantly higher capillarization in the young compared to the old individuals, in the healthy compared to the diseased individuals, and in the endurance-trained and endurance well-trained compared to the untrained individuals. CONCLUSIONS: The results of this study support the conclusion that the capillary supply of skeletal muscle is closely regulated by factors aimed at optimizing oxygen and nutrient supply and/or waste removal in response to changes in muscle mass and/or metabolic activity.

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This research was directed towards the investigation and development of an aryne route to the syntheses of aporphi ne and dibenzopyrrocolinium (dibenzoindolizinium) alkaloids and to the stability of the latter under the conditions used for aryne formation. The work c an be divided into three main sections . i) - Synthesis of Glaucine 6-Bromo-3,4-dimethoxyphenylacetic acid, prepared by the action of bromine i n acetic acid on3,4-dimethoxyphenylacetic a cid, was converted into its acid chloride by t he action of thionyl chloride. This on treatment with 3,4- dimethoxyphenylethylamine pr ovided N-(3, 4-dimethoxyphenylethyl)- 2-(2-bromo-4,S-dimethoxyphenyl)-acetamide which on dehydration with phosphoryl chloride (Bischler Napieralski reaction) in dry benzene afforded l -(2-bromo-4,S-dimethoxybenzyl)- 3,4-dihydro-6,7-dimethoxyisoquinoline, isolated as hydrochl oride. A new method o f destroying the excess of phosphoryl chloride was developed which proved to be quite useful. Methylation of the dihydroisoquinoline'with methyl iodide in methanol , and subsequent reduction with sodium borohydride provided (±)-6-bromolaudanosine. Act ion of potassamide or sodamide in anhydrous liquid ammonia on (±)-6-bromolaudanosine yielded the corresponding amino derivative along with other products. Diazotization and ring closure of (±)-6-aminolaudanosine then a f forded (±)-glaucine which was isolated as methiodide. ii) - Intramolecular Capture of Aryne During Glaucine Synthesis, and Subsequent Reactions . This section deals with the by-products formed under the conditions of the aryne stage of t he glaucine synthesis. The crude product, obtained in the reaction of potassamide or sodamide in liquid ammonia on (±)-6-bromolaudanosine, was s eparated by chromatography, Three products were separated and identified. a ) - 5,6-Dimethoxy-2-( 3,4-dimethoxy-6-ethylphenyl)-lmethylindole. Two mechanisms are proposed for the formation of this interesting product. This compound also was prepared by the action of potassamide in l,iquid ammonia on 5,6 ,l2,l2atetrahydro- 2,3,9,lO-tetramethoxy-7-methyldibenz[b,g]indolizinium i odide . b) - 5,6-Dimethoxy-2-(3,4-dimethoxy-6-vinylphenyl)-lmethylindoline. Its formation represented a new method of Hofmann degradation . Further confirmation of structure was done by performing the normal Hofmann reaction on 5, 6,12,12a-tetrahydro -2/3,9,lO-tetramethoxy ~7-methyldibe nz[ b,g]indolizinium iodide. The indoline prepared i n this way was identical in all respects with that prepared above . c) - 1- (2-amino-4,5-dimethoxybenzyl ) -l,2,3,4-tetrahydro-2- methyl-6,7-dimethoxyisoquinoline, was converted t o glaucine as stated in section 1 . iii) - Attempt:,ed Sxnthesis of Liriodenine Piperonal was converted into 3,4-methylenedioxyinitrostyrene which on reduction with lithium aluminium hydride provided 3,4-methylenedioxyphenylethylamine. The method of extraction after the reduction was improved t o some extent. The amine on condensation with m-chlorophenylacetyl chloride, prepared by the action of oxalyl chloride on 3,4-methylenedioxyphenylacetic acid, provided N-[ ~ -(3,4-methylenedioxyphenyl)- e thyl)-3-chlorophenylacetamide. This on dehydration with phosphoryl chloride in dry benzene followed by air oxidation afforded l-(3-chlorobenzoyl)-6,7-methylenedioxyi soquinoline. This compound on r eaction with potassamide in liquid ammonia afforded a crude product from which. one product was separated by chromatography i n a pure condition . This yellow compound analysed as,c17Hl ON2021 and was t he main product i n the reaction ; a t entative structure is proposed. A second compound, not obtained in pure condition, was submitted to Pschorr reaction in the hope of obtaining liriodenine, but without success.

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The implementation of imagery and video feedback programs has become an important tool for aiding athletes in achieving peak performance (Halliwell, 1990). The purpose of the study was to determine the effect of strategic imagery training and video feedback on immediate performance. Participants were two university goaltenders. An alternating treatment design (ATD; Barlow & Hayes, 1979; Tawney & Gast, 1984) was employed. The strategies were investigated using three plays originating from the right side by a right-handed shooting defenceman from the blueline. The baseline condition consisted of six practices and was used to establish a stable and "ideal" measure of performance. The intervention conditions included alternating the use of strategic imagery (Cognitive general; Paivio, 1985) and video feedback. Both participants demonstrated an increase in the frequency of Cognitive general use. Specific and global performance measures were assessed to determine the relative effectiveness of the interventions. Poor inter-rater reliability resulted in the elimination of specific performance measures. Consequently, only the global measure (i.e., save percentage) was used in subsequent analyses. Visual inspection of participant save percentage was conducted to determine the benefits of the intervention. Strategic imagery training resulted in performance improvements for both participants. Video feedback facilitated performance for Participant 2, but not Participant 1. Results are discussed with respect to imagery and video interventions and the challenges associated with applied research. KEYWORDS: imagery, video, goaltenders, alternating treatment design.

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The Niagara Navigation Company Limited, popularly known as the Niagara River Line.

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In this thesis, I focus on supply chain risk related ambiguity, which represents the ambiguities firms exhibit in recognizing, assessing, and responding to supply chain disruptions. I, primarily, argue that ambiguities associated with recognizing and responding to supply chain risk are information gathering and processing problems. Guided by the theoretical perspective of bounded rationality, I propose a typology of supply chain risk related ambiguity with four distinct dimensions. I, also, argue that the major contributor to risk related ambiguity is often the environment, specifically the web of suppliers. Hence, I focus on the characteristics of these supplier networks to examine the sources of ambiguity. I define three distinct elements of network embeddedness – relational, structural, and positional embeddedness – and argue that the ambiguity faced by a firm in appropriately identifying the nature or impacts of major disruptions is a function of these network properties. Based on a survey of large North American manufacturing firms, I found that the extent of the relational ties a firm has and its position in the network are significantly related to supply chain risk related ambiguity. However, this study did not provide any significant support for the hypothesized relationship between structural embeddedness and ambiguity. My research contributes towards the study of supply chain disruptions by using the idea of bounded rationality to understand supply chain risk related ambiguity and by providing evidence that the structure of supply chain networks influences the organizational understanding of and responses to supply chain disruptions.

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Report (20 page booklet) on a water supply for the town of St. Catharines by Thomas Monro, civil engineer. This is addressed to Lucious S. Oille, M.D., chairman of the Water Committee of St. Catharines, June 10, 1875.