3,652 research outputs found

    LeRC reduced gravity fluid management technology program

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    A survey of the reduced gravity fluid management technology program is presented. Information on reduced gravity fluid behavior, techniques for thermal control of cryogenic tankage, and design for fluid management systems are discussed. The development of Spacelab experiments, propellant management systems for orbit transfer vehicles, and computer techniques for simulating reduced gravity fluid dynamic processes is reported

    The Mining and Smelting of Copper in England and Wales, 1760-1820

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    This thesis traces the development of the copper industry, mining and smelting, located mainly in Cornwall and South Wales respectively, between 1760 and 1820, and the interaction between them. It is especially concerned with the impact on the mining industry of new sources of ore, technological change, and the regionalisation of copper smelting. Whereas previous work has tended to regard mining and smelting as two regionally distinct quasi–independent industries, they are here treated as interdependent, exemplified by a complex web of collusion, cartel and monopoly. The thesis is in four main sections. Initially, it examines the geology and geography of the two industries to establish the reasons for their segregation. This is followed by a chapter explaining the structure and economics of mining. The third chapter explores the growth of the smelting industry, examining the early regional distribution of the industry, and its ultimate consolidation in South Wales. The fourth chapter opens with a brief overview of the demand for copper, continuing with an extended discussion on the marketing of ore and metal. The effect of Boulton and Watt’s patent in respect of the improvements made to the steam engine is examined. To date our understanding of the copper industry in the eighteenth and early nineteenth centuries has been derived largely from studies of the late nineteenth century. This thesis argues that it is misleading to reach conclusions about an earlier period on the conclusions of later studies. Available statistical evidence for the period from 1760 to 1820 is examined, notably that contained in the 'Report from the Committee Appointed to Enquire into the State of the Copper Mines and Copper Trade of this Kingdom', published on 7th May 1799. This provides the basis for an evaluation of productivity, and of company and shareholder profits. It is also shown that there was a correlation with the output of tin, many mines being producers of both ores. In relation to the marketing of ore in this period it is argued that the value of the copper content was not the only determinant of market price, as previous accounts have suggested. Instead, the value based on an assumed constant yield appears to have been a key factor in the early years. Finally, collusion emerges as an important theme. Previous work has pointed to the tendency of the South Wales smelting companies to collude for the purpose of price fixing. It is also argued that they also sought through collusion to achieve an optimum mix of ore to facilitate efficient smelting. Other restrictive practices are identified, notably those relating to Boulton and Watt's monopoly in the imposition of their engine patent, and the emergence of a short–lived marketing cartel in the form of the Cornish Metal Company (1785 – 92), which sought to counter the dominant influence of the South Wales smelting companies. For much of the fourth quarter of the eighteenth century, the industry was dominated by Thomas Williams, managing director of the Anglesey mines, associated smelters and other manufacturing interests, whose opposition to the South Wales smelting companies resulted in him achieving a total monopoly of the copper trade in the late 1780s and early 1790s

    L'avis d'ouverture de chantier informatisé: un moyen de prévention et de management

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    L’instruction de sécurité IS 39 stipule que les travaux exécutés par des entreprises sur le domaine du CERN doivent faire l’objet d’un Avis d’Ouverture de Chantier (AOC) rédigé par le superviseur des travaux avant le démarrage de ceux-ci, dans le but d’attirer l’attention sur les risques et les nuisances qu’ils peuvent engendrer pour les usagers dans la zone de travaux. A cet effet, un groupe de travail a spécifié une version informatisée du document AOC sur EDH afin d’en faciliter la saisie, la visualisation ainsi que la gestion et l’archivage ; à cela s’ajoutent la description des risques et mesures préventives possibles, la consultation des différentes bases de données CFU (Contract Follow Up), du patrimoine immobilier et finalement toutes les commodités liées à EDH pour le routage du document selon la liste des rôles des personnes concernées (approbation, distribution pour information). Dès lors, l’AOC devient un moyen d’analyse et de gestion (détection et traçabilité des co-activités, des travaux selon les emplacements, firmes intervenantes et dates) grâce aux différents critères et calculs selon lesquels il est manipulé par les utilisateurs

    Growth hormone receptor and insulin-like growth factor-I immunoreactivity in osteoclast-like cells during tooth eruption in the toothless (Osteopetrotic) rat following treatment with colony-stimulating factor-1

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    In the toothless (tl/tl) osteopetrotic rat, teeth form but fail to erupt. Treatment of tl/tl rats with colony-stimulating factor-1 (CSF-1) activates bone resorption by osteoclasts, permits tooth eruption, and up-regulates the immunoreactivity of bone marrow mononuclear cells to growth hormone receptor (GHr) and insulin-like growth factor (IGF)-I. This study examined the distribution of tartrate-resistant acid phosphatase (TRAP) and immunoreactivity for GHr and IGF-I in osteoclast-like cells located on the alveolar bone margin, adjacent to the lower first molar crown, in 14-day-old normal and tl/tl rats, following treatment with CSF-1. Osteoclast-like cells demonstrated a positive reaction for TRAP, GHr, and IGF-I in all groups. However, in tl/tl tissue, osteoclast-like cells were generally negative for GHr. There was no significant difference in the total number of TRAP, GHr, and IGF-I-positive osteoclast-like cells on the adjacent bone margin in normal, normal treated with CSF-1, and tl/tl rats. CSF-1 treatment of the tl/tl rat significantly increased the total number of osteoclast-like cells, which were positive for TRAP (p < 0.001), GHr (p < 0.05) and IGF-I (P < 0.01)

    C1 inhibitor deficiency: 2014 United Kingdom consensus document

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    C1 inhibitor deficiency is a rare disorder manifesting with recurrent attacks of disabling and potentially life-threatening angioedema. Here we present an updated 2014 United Kingdom consensus document for the management of C1 inhibitor-deficient patients, representing a joint venture between the United Kingdom Primary Immunodeficiency Network and Hereditary Angioedema UK. To develop the consensus, we assembled a multi-disciplinary steering group of clinicians, nurses and a patient representative. This steering group first met in 2012, developing a total of 48 recommendations across 11 themes. The statements were distributed to relevant clinicians and a representative group of patients to be scored for agreement on a Likert scale. All 48 statements achieved a high degree of consensus, indicating strong alignment of opinion. The recommendations have evolved significantly since the 2005 document, with particularly notable developments including an improved evidence base to guide dosing and indications for acute treatment, greater emphasis on home therapy for acute attacks and a strong focus on service organisation. This article is protected by copyright. All rights reserved

    Guide pour l'établissement des plans de prévention et de sécurité des entreprises extérieures: Travaux et prestations de catégorie 2

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    Ce document a été élaboré par un groupe de travail ST/DI et TIS/GS en collaboration avec un préventeur / consultant de l'APAVE. Il est destiné à servir de guide et de référence pour l'élaboration des plans de prévention au sein de la division ST

    The genetic control of avascular area in mouse oxygen-induced retinopathy

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    Purpose: The C57BL/6ByJ and BALB/cByJ inbred strains of mice are, respectively, susceptible and resistant to oxygen-induced retinopathy (OIR). The purpose of this work was to investigate the genetic control of the retinal avascular area in mouse OIR using a mapping cross. Methods: The central retinal avascular area was measured on postnatal day 16 (P16) in C57BL/6ByJ, BALB/cByJ, 101 (C57BL/6ByJ x BALB/cByJ)F2, and 116 (BALB/cByJ x C57BL/6ByJ)F2 mice that had been subjected to the OIR protocol. A genome-wide scan was performed of selected albino and non-albino mice to determine quantitative trait loci associated with weight and avascular area. Results: C57BL/6ByJ mice had significantly larger avascular areas than BALB/cByJ ones. Albino mice of the F2 generation had smaller avascular areas than the non-albino mice. Genotyping was performed at 856 informative single nucleotide polymorphisms approximately evenly distributed across the genome from each of 85 selected F2 mice. Weight, sex, and the paternal grandmother were found to act as additive covariates associated with the avascular area on P16; mapping analyses that used a model incorporating these covariates found a quantitative trait locus on chromosome 7 related to avascular area. Mapping analyses that used a model that did not incorporate covariates found a quantitative trait locus on chromosome 9 related to avascular area. A quantitative trait locus for bodyweight on P16 was mapped to chromosome 5. Conclusions: The retinal avascular area in the mouse OIR model is under genetic control. Revascularization in OIR is related to the weight, strain of paternal grandmother, sex, and albinism. Our data support the existence of a quantitative trait locus on chromosome 5 that influences weight after exposure to hyperoxia, as well as quantitative trait loci on chromosomes 7 and 9 that modify susceptibility to OIR

    Growth hormone receptor and IGF-1 receptor immunoreactivity during orthodontic tooth movement in the prednisolone-treated rat

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    Bone remodeling during tooth movement is regulated by local and systemic factors. Two regulators of bone metabolism are growth hormone (GH) and insulin-like growth factor-I (IGF-1). Their effects are mediated via binding to GH receptor (GHR) and IGF-I receptor (IGF-IR) in target tissues. Corticosteroids may affect the activity of these growth factors. This study examined the effect of prednisolone on GHR and IGF-IR expression in dental tissues following orthodontic tooth movement. The corti ticosteroid-treated group (N = 6) was administered prednisolone ( 1 mg/kg,) daily and the control group (N = 6) received equivalent volumes of saline. An orthodontic force (30 g) was applied to the maxillary first molar. Animals were sacrificed 12 days postappliance insertion. Sagittal sections of the first molar were stained for GHR and IGF-IR immunoreactivity. GHR and IGF-IR cell counts were elevated following appliance-treatment. Orthodontic tooth movement appeared to up-regulate GHR and IGF-IR immunoreactivity, but this up-regulation was reduced following prednisolone treatment. The suppression of GHR and IGF-I immunoreactivity in steroid-treated animals infers the mechanism whereby bone resorption and deposition, necessary for orthodontic tooth movement, may be inhibited by prednisolone. However, at 12 days postappliance insertion. no difference in orthodontic tooth movement was observed following low-dose prednisolone treatment
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