1,739 research outputs found

    Investigation of abort procedures for space shuttle-type vehicles

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    An investigation has been made of abort procedures for space shuttle-type vehicles using a point mass trajectory optimization program known as POST. This study determined the minimum time gap between immediate and once-around safe return to the launch site from a baseline due-East launch trajectory for an alternate space shuttle concept which experiences an instantaneous loss of 25 percent of the total main engine thrust

    The equilibrium free surface of a contained liquid under low gravity and centrifugal forces

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    Equilibrium free surface of contained liquid under effects of low gravity, translational and angular acceleration, and capillary force

    Locke, Tocqueville, Liberalism, and Restlessness

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    Thesis advisor: Robert K. FaulknerWhy are men in modern societies so busy and anxious? Modern, liberal democratic society is distinguished both by the unprecedented strength and prosperity it has achieved, as well as its remarkable number of psychologists per capita. Why is this? This dissertation explores the connection between restlessness and modernity by way of an examination of the themes of liberalism and restlessness in the thought of Locke and Tocqueville. "Restlessness" refers to a way of life characterized by three features: limitless desires, mildness, and an orientation towards material goods. Tocqueville argues in Democracy in America that democracy, by way of individualism, makes men materialistic and restless (inquiét), or restlessly materialistic. The intense, limitless pursuit of material well-being is a historical phenomenon, one of the many results of the centuries-long development of equality of conditions. Modern democrats are restless; pre-modern aristocrats were not. Tocqueville is ambivalent about restlessness. According to him, the incessant, energetic movement of American life conceals an underlying absurdity and mediocrity. Many of what Tocqueville views as the more undesirable qualities of democratic American life are associated with restlessness, but any solution is likely to be worse than the problem. It could be worse: we must tolerate restlessness if we want to remain free. "All free peoples are grave." Locke by contrast could be described as a partisan of restlessness. The anxious understand the world better than the complacent or vegetative. There are two dimensions to Locke's teaching on restlessness, an "is" (found in Essay concerning Human Understanding Book II Chapter 21) and an "ought" (found in "Of Property," Chapter Five of the Second Treatise). Our desires are naturally limitless-this we can only understand, we cannot change it. But if we know what's good for us, we will orient ourselves towards a milder and more materialistic way of life. We master restlessness by becoming more restless, or restless in a more enlightened way. Locke's teaching on restlessness in the fullest sense is partly his account of necessity, and partly his recommended response to necessity. This difference in their views on restlessness points to certain important differences in their liberalisms. Tocqueville's liberalism is more pessimistic than Locke's: some fundamental problems have no solutions, and some of the highest goods cannot be reconciled with one another. Lockean liberalism is more confident about its ability to find solutions to the fundamental problems of political life, and there is no problem of the harmony of the goods for Locke.Thesis (PhD) — Boston College, 2010.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Political Science

    A novel 2- and 3-choice touchscreen-based continuous trial-unique nonmatching-to-location task (cTUNL) sensitive to functional differences between dentate gyrus and CA3 subregions of the hippocampus.

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    RATIONALE: The touchscreen continuous trial-unique non-matching-to-location task (cTUNL) has been developed to optimise a battery of tasks under NEWMEDS (Novel Methods leading to New Medication in Depression and Schizophrenia, http://www.newmeds-europe.com ). It offers novel task features of both a practical and a theoretical nature compared to existing touchscreen tasks for spatial working memory. OBJECTIVES: The objective of this study was to determine whether the cTUNL task is sufficiently sensitive to differentiate between dentate gyrus (DG) and CA3 hippocampal subregion contributions to performance. METHODS: The effect of DG and CA3 dysfunction on memory for locations in the cTUNL task was tested. Rats were assessed on versions of the task-two-choice and three-choice-that differed in memory load. Performance was challenged using manipulations of delay and the spatial separation between target and sample locations. RESULTS: Dysfunction of the DG disrupts performance across both delay and spatial separations in two-choice cTUNL when the delay is variable and unpredictable. Increasing the working memory load (three stimuli) increases sensitivity to DG dysfunction, with deficits apparent at fixed, short delays. In contrast, CA3 dysfunction did not disrupt performance. CONCLUSION: Acquisition of cTUNL was rapid, and the task was sensitive to manipulations of delays and separations. A three-choice version of the task was found to be viable. Finally, both the two- and three-choice versions of the task were able to differentiate between limited dysfunction to different areas within the hippocampus. DG dysfunction affected performance when using unpredictable task parameters. CA3 dysfunction did not result in impairment, even at the longest delays tested.This work was supported by the Innovative Medicine Initiative Joint Undertaking under grant agreement no. 115008 of which resources are composed of EFPIA inkind contribution and financial contribution from the European Union’s Seventh Framework Programme (FP7/2007-2013). As part of this project, CAO was funded by Janssen Pharmaceuticals, Inc., of Johnson & Johnson.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s00213-015-4019-

    Leptospirosis severity may be associated with the intensity of humoral immune response

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    Leptospirosis severity may be increasing, with pulmonary involvement becoming more frequent. Does this increase result from an intense immune response to leptospire? Notice that renal failure, thrombocytopenia and pulmonary complications are found during the immune phase. Thirty-five hospitalized patients with Weil's disease had 5 blood samples drawn, from the 15th day to the 12th month of symptoms, for ELISA-IgM, -IgG and -IgA specific antibody detection. According their 1st IgG titer, the patients were divided into: group 1 (n = 13) titer >; 1:400 (positive) and group 2 (n = 22) titerA gravidade da leptospirose parece estar aumentando principalmente quanto ao envolvimento pulmonar. Essa maior gravidade poderia ser decorrente de uma resposta imunológica mais intensa, já que tanto a insuficiência renal, quanto a plaquetopenia e as lesões pulmonares são encontradas na fase imune da doença. Para investigar esta hipótese foram detectados por ELISA anticorpos IgM, IgG e IgA específicos em amostras de sangue de 35 pacientes internados com síndrome de Weil colhidas a partir de cerca de 15 dias do início dos sintomas até 1 ano após a alta. Os pacientes foram divididos em 2 grupos conforme o seu título de IgG na primeira amostra, colhida com até 2 semanas de sintomas: grupo 1 (n = 13) com título >;1:400 (positivo) e grupo 2 (n = 22) com títul

    Cardiac output in idiopathic normal pressure hydrocephalus: association with arterial blood pressure and intracranial pressure wave amplitudes and outcome of shunt surgery

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    <p>Abstract</p> <p>Background</p> <p>In patients with idiopathic normal pressure hydrocephalus (iNPH) responding to shunt surgery, we have consistently found elevated intracranial pressure (ICP) wave amplitudes during diagnostic ICP monitoring prior to surgery. It remains unknown why ICP wave amplitudes are increased in these patients. Since iNPH is accompanied by a high incidence of vascular co-morbidity, a possible explanation is that there is reduced vascular compliance accompanied by elevated arterial blood pressure (ABP) wave amplitudes and even altered cardiac output (CO). To investigate this possibility, the present study was undertaken to continuously monitor CO to determine if it is correlated to ABP and ICP wave amplitudes and the outcome of shunting in iNPH patients. It was specifically addressed whether the increased ICP wave amplitudes seen in iNPH shunt responders were accompanied by elevated CO and/or ABP wave amplitude levels.</p> <p>Methods</p> <p>Prospective iNPH patients (29) were clinically graded using an NPH grading scale. Continuous overnight minimally-invasive monitoring of CO and ABP was done simultaneously with ICP monitoring; the CO, ABP, and ICP parameters were parsed into 6-second time windows. Patients were assessed for shunt surgery on clinical grade, Evan's index, and ICP wave amplitude. Follow-up clinical grading was performed 12 months after surgery.</p> <p>Results</p> <p>ICP wave amplitudes but not CO or ABP wave amplitude, showed good correlation with the response to shunt treatment. The patients with high ICP wave amplitude did not have accompanying high levels of CO or ABP wave amplitude. Correlation analysis between CO and ICP wave amplitudes in individual patients showed different profiles [significantly positive in 10 (35%) and significantly negative in 16 (55%) of 29 recordings]. This depended on whether there was also a correlation between ABP and ICP wave amplitudes and on the average level of ICP wave amplitude.</p> <p>Conclusions</p> <p>These results gave no evidence that the increased levels of ICP wave amplitudes seen in iNPH shunt responders prior to surgery were accompanied by elevated levels of ABP wave amplitudes or elevated CO. In the individual patients the correlation between CO and ICP wave amplitude was partly related to an association between ABP and ICP wave amplitudes which can be indicative of the state of cerebrovascular pressure regulation, and partly related to the ICP wave amplitude which can be indicative of the intracranial compliance.</p

    Clinical Pharmacy: Looking 20 Years Back… Looking 20 Years Forward

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90209/1/phco.20.16.235S.35021.pd

    Sugar Beet Root Storage Properties Are Unaffected by Cercospora Leaf Spot

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    © 2023 The American Phytopathological Society. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1094/PDIS-09-22-2156-RECercospora leaf spot (CLS; causal agent Cercospora beticola Sacc.) is endemic in many sugar beet production regions due to the widespread distribution of C. beticola and the inability of current management practices to provide complete control of the disease. Roots harvested from plants with CLS, therefore, are inevitably incorporated into sugar beet root storage piles, even though the effects of CLS on root storage properties are largely unknown. Research was conducted to determine the effects of CLS on storage properties including root respiration rate, sucrose loss, invert sugar accumulation, loss in recoverable sucrose yield, and changes in sucrose loss to molasses with respect to CLS disease severity and storage duration. Roots were obtained from plants with four levels of CLS severity in each of three production years, stored at 5°C and 95% relative humidity for up to 120 days, and evaluated for storage characteristics after 30, 90 and 120 days storage. No significant or repeatable effects of CLS on root respiration rate, sucrose loss, invert sugar accumulation, loss in recoverable sucrose yield, or change in sucrose loss to molasses were detected after 30, 90 or 120 days storage regardless of the severity of CLS disease symptoms. Therefore, no evidence was found that CLS accelerates sugar beet storage losses, and it is concluded that roots harvested from plants with CLS can be stored without additional or specialized precaution, regardless of CLS symptom severity.Peer reviewe
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