3,358 research outputs found
Space Station alpha joint bearing
Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described
VALUING WATER QUALITY MONITORING: A CONTINGENT VALUATION EXPERIMENT INVOLVING HYPOTHETICAL AND REAL PAYMENTS
This paper studies the preferences and willingness-to-pay for individuals for volunteer water quality monitoring programs. The study involves supporting water quality monitoring at two ponds in the state of Rhode Island. The paper uses both a hypothetical and a real-payment contingent valuation survey to directly measure individual preferences and willingness-to-pay (WTP) for volunteer water quality monitoring at the two ponds. The overall results of the study suggest that hypothetical WTP is not statistically greater than real WTP, and that the average survey respondent is willing to support water quality monitoring on one of the two ponds. The study also finds that the specified purpose of water quality monitoring and certain socioeconomic characteristics of a respondent significantly affect the respondent's decision to support volunteer water quality monitoring.Environmental Economics and Policy,
Policing Diversity: Lessons from Lambeth
This report describes a local initiative, Policing Diversity in Lambeth (PDL), which was developed to address the challenges of policing a highly ethnically diverse population.
The report is timely. The report of the Macpherson Inquiry into the death of Stephen Lawrence has substantially redrawn the policy landscape in relation to policing and race issues. The Home Secretary’s priorities for policing in 2000-1 emphasise the need for improved community relations. The follow-up report by Her Majesty’s Inspectorate of Constabulary, ‘Winning the Race Revisited’, further stressed the need for urgent action. Parallel with these developments, the 1998 Crime and Disorder Act imposed a duty on police and local authorities to work to reduce crime in partnerships with local communities, and to engage more fully in consultation with local communities.
The report provides a snapshot of PDL at a particular stage in its development, and this report may seem of historical interest only. However, the analysis of underlying relations between the police and the community will have wider applicability for both the police and crime and disorder partnerships, as do the lessons that can be drawn from PDL’s first year
Long-term effects of adolescent stress on neophobic behaviors in zebra finches are modulated by social context when in adulthood
Funding was provided by a BBSRC Research Fellowship to KAS and a University of St Andrews postgraduate scholarship to MGE.Experiencing stress during adolescence can increase neophobic behaviors in adulthood, but most tests have been conducted in the absence of conspecifics. Conspecifics can modulate responses to stressors, for example by acting as ‘social buffers’ to attenuate the aversive appraisal of stressors. Here, we investigate the long-term effects of adolescent stress on the behavioral responses to novel stimuli (a mild stressor) across social contexts in an affiliative passerine bird, the zebra finch. During early (days 40–60) or late (days 65–85) adolescence the birds (n = 66) were dosed with either saline or the hormone corticosterone (CORT). CORT was given in order to mimic a physiological stress response and saline was given as a control. In adulthood, the birds' behavioral responses to a novel environment were recorded in both the presence and absence of conspecifics. An acute CORT response was also quantified in adolescence and adulthood. Our findings show clear evidence of social context mediating any long-term effects of adolescent stress. In the presence of familiar conspecifics no treatment effects were detected. Individually, birds dosed with CORT in early adolescence were slower to enter a novel environment, spent more time perching in the same novel environment, and, if female, engaged in more risk assessment. Birds dosed in late adolescence were unaffected. No treatment effects were detected on CORT, but adolescents had a higher CORT concentration than adults. Our results are the first to suggest that familiar conspecifics in adulthood can buffer the long-term effects of stress that occurred during early adolescence.Publisher PDFPeer reviewe
Culture and rapport promotion in service encounters: protecting the ties that bind
The present study aimed at investigating possible cultural effects on the perceived importance of interactional concerns in service encounters. Individual values were examined to establish an explanatory framework for any effects that might emerge. Hong Kong Chinese and Filipinos participated in the present study by rating the importance of 12 interactional concerns in five hypothetical scenarios involving service provision. “Rapport promotion” was the only consistent factor of interactional concerns to emerge from the five scenarios in each of the two cultural groups. The dimensions of individual values, labeled “Conservation” and “Self-Transcendence” by Schwartz (1992), significantly predicted a respondent’s level of rapport promotion across all scenarios, with self-transcendence partially unpackaging the cultural difference that emerged in one of the service scenarios. We use these results to support a model of communication in service provision that predicts communication concerns as arising from cultural socialization for personal characteristics and situational features of the encounter, leading to the petitioner’s being more dependent on the good will of the service provider
Group housing during adolescence has long-term effects on the adult stress response in female, but not male, zebra finches (Taeniopygia guttata)
Funding was provided by a BBSRC David Phillips Research Fellowship to KAS and a University of St Andrews postgraduate scholarship to MGE.Adolescent social interactions can have long-term effects on physiological responses to stressors in later-life. A larger adolescent group size can result in higher stressor-induced secretion of glucocorticoids in adulthood. The effect may be due to a socially-mediated modulation of gonadal hormones, e.g. testosterone. However, group size (number of animals) has been conflated with social density (space per animal). Therefore it is hard to determine the mechanisms through which adolescent group size can affect the stress response. The current study aimed to tease apart the effects of group size and social density during adolescence on the physiological stress response and gonadal hormone levels in adulthood. Adolescent zebra finches were housed in groups varying in size (2 vs. 5 birds per cage) and density (0.03m3 vs. 0.06m3 per bird) during early adolescence (day 40-60). Density was only manipulated in birds raised in groups of five. Glucocorticoid concentration secreted in response to a standard capture and restraint stressor was quantified in adolescence (day 55±1) and adulthood (day 100+). Basal gonadal hormones concentrations (male testosterone, female estradiol) were also quantified in adulthood. Female birds housed in larger groups, independent of social density, secreted a higher glucocorticoid concentration 45 mins into restraint regardless of age, and had higher peak glucocorticoid concentration in adulthood. Adult gonadal hormone concentrations were not affected by group size or density. Our results suggest that group size, not density, is a social condition that influences the development of the endocrine response to stressors in female zebra finches, and that these effects persist into adulthood. The findings have clear relevance to the social housing conditions necessary for optimal welfare in captive animals, but also elucidate the role of social rearing conditions in the emergence of responses to stressors that may persist across the lifespan and affect fitness of animals in wild populations.Publisher PDFPeer reviewe
Evolution in Natural Area Monitoring at Indianapolis Parks
The Indianapolis Land Stewardship (ILS) team’s first restoration was in 1992 with high school students planting acorns in a 13-acre field. Since then, managed acreage has increased to nearly 1,900 acres across 37 parks. ILS’ monitoring has evolved to meet the challenges of an expanding program. This is accomplished through improved GIS tracking and mapping techniques. Additionally, scientific survey work has broadened from initially a few vegetation surveys to now include longer-duration studies and other taxa for a more balanced and complete assessment
Good functional recovery following intervention for delayed suprachoroidal haemorrhage post bleb needling: a case report
<p>Abstract</p> <p>Introduction</p> <p>Bleb needling is a recognised procedure in the management of patients with failing trabeculectomies. Suprachoroidal haemorrhage can occur as an unusual complication. We report a pseudophakic man who had early surgical intervention for this complication. This intervention may have contributed to the good recovery of his visual acuity and the minimum changes to his visual fields.</p> <p>Case presentation</p> <p>A 79-year-old pseudophakic man with chronic open angle glaucoma presented with further deterioration of his right visual field despite maximum medical therapy and a previous trabeculectomy. The right visual acuity was 6/9 with an intraocular pressure (IOP) of 16 mmHg. Bleb needling with 5-fluouracil was performed in a standard manner. His postoperative IOP was 6 mmHg. Thirty-six hours later the visual acuity was reduced to hand movements and two large choroidal detachments where observed clinically, which progressed to suprachoroidal haemorrhages. Five days after the initial needling, the patient had complex surgery involving anterior chamber reformation, a bleb compression suture and drainage of the haemorrhagic suprachoroidal detachments. Subsequently, the patient had a right vitrectomy with endolaser following a vitreous haemorrhage. The final visual acuity was 6/9 with an intraocular pressure of 8 mmHg on travoprost and brinzolamide. The final visual field showed little change when compared with the pre-suprachoroidal haemorrhage visual field.</p> <p>Conclusion</p> <p>It is important to consider the possibility of delayed suprachoroidal haemorrhage as a complication in bleb needling, and early surgical intervention may be beneficial.</p
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