4,103 research outputs found

    A NEW FORM OF DIFFRACTOMETER

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    A simple diffractometer is described, in which monochromatic light is focused on a pinhole, rendered parallel, and passed through a film of red cells or other objects the size of which is sought. The diffraction patterns are photographed on special plates, and the positions of the first minimum and of the first maximum are subsequently found by the use of a simplified microphotometer. The method gives substantially the same results for red cell radius and (calculated) volume as do other standard methods

    Comparison of Environmental Assessments of Two Proposed Harbor Expansions on the Mississippi River

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    The National Environmental Policy Act of 1969 requires federally funded projects to be evaluated for environmental impact to determine if a complete environmental impact statement must be prepared. Such an environmental assessment must also be included in any feasibility study for harbor enlargement and bank stabilization measures under the Water Resources Development Act. Population increases, coupled with economic growth from increased agricultural and industrial productivity, have resulted in increased Mississippi River barge transportation needs for Arkansas and Missouri. We report here two such environmental assessments of planned harbor expansions of the New Madrid County and Pemiscot County ports in the Missouri bootheel along the Mississippi River. We evaluated the environmental settings, presence of wetlands, and the presence of hazardous, toxic or radioactive wastes (HTRW) at the two sites. The results of these evaluations were used to determine the possible significant resources and impacts (including endangered species) associated with harbor expansion at the two sites. No significant HTRW were present or likely to be encountered during construction at either site. However, differences in 1) the environmental settings (open high banks vs. bottomland forest), 2) significant resources (historical accounts of least tern colonies at one site), and 3) presence of wetland habitat at one site may preclude or reduce the level of one or both harbor expansions. Careful consideration of possible environmental impacts may help guide the choice of sites for similar harbor expansions in Arkansas

    Study of atmospheric dynamics

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    In order to better understand the dynamics of the global atmosphere, a data set of precision temperature measurements was developed using the NASA built Microwave Sounding Unit. Modeling research was carried out to validate global model outputs using various satellite data. Idealized flows in a rotating annulus were studied and applied to the general circulation of the atmosphere. Dynamic stratospheric ozone fluctuations were investigated. An extensive bibliography and several reprints are appended

    Probability of a Clear Line-of-Sight Through the Atmosphere for a Satellite Based Laser Communications System: A Feasibility Study

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    The NASA Earth Resources Technology Satellite (ERTS) program is considering the possible use of laser communications to transmit data between a satellite and earth. Such a transmission requires a relatively clear line-of-sight between the satellite and a receiving station on earth. This study considers the effect of clouds on laser transmissions from space. To get an indication of the receiving capabilities for a selection of ground receiving stations, the authors made a preliminary evaluation of the monthly mean percentage-of-possible-sunshine statistics. With a network of six stations optimally placed, a satellite passing over the contiguous United States would generally be within range of three or more of the stations. With this choice of receiving stations the preliminary evaluation indicated a high probability of data receipt via laser communications. To test the capability of such a network of ground stations more rigorously and to consider only the planned (morning) hours of ERTS passage, a simulated operation used 5 years of January and July data. A relationship was established between the reported opaque sky cover and the minutes of sunshine recorded in the hour in which the cloud observation was made. The simulations involved a series of hypothetical satellite crossings over the United States. For each crossing, probabilities of clear line-of-sight were calculated from the opaque sky cover observations and the relationship established between opaque sky cover and sunshine

    As Time Goes by: Understanding Child and Family Factors Shaping Behavioral Outcomes After Traumatic Brain Injury

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    Objective: To model pre-injury child and family factors associated with the trajectory of internalizing and externalizing behavior problems across the first 3 years in children with pediatric traumatic brain injury (TBI) relative to children with orthopedic injuries (OI). Parent-reported emotional symptoms and conduct problems were expected to have unique and shared predictors. We hypothesized that TBI, female sex, greater pre-injury executive dysfunction, adjustment problems, lower income, and family dysfunction would be associated with less favorable outcomes. Methods: In a prospective longitudinal cohort study, we examined the level of behavior problems at 12 months after injury and rate of change from pre-injury to 12 months and from 12 to 36 months in children ages 4–15 years with mild to severe TBI relative to children with OI. A structural equation model framework incorporated injury characteristics, child demographic variables, as well as pre-injury child reserve and family attributes. Internalizing and externalizing behavior problems were indexed using the parent-rated Emotional Symptoms and Conduct Problems scales from the Strengths and Difficulties questionnaire. Results: The analysis cohort of 534 children [64% boys, M (SD) 8.8 (4.3) years of age] included 395 with mild to severe TBI and 139 with OI. Behavior ratings were higher after TBI than OI but did not differ by TBI severity. TBI, higher pre-injury executive dysfunction, and lower income predicted the level and trajectory of both Emotional Symptoms and Conduct Problems at 12 months. Female sex and poorer family functioning were vulnerability factors associated with greater increase and change in Emotional Symptoms by 12 months after injury; unique predictors of Conduct Problems included younger age and prior emotional/behavioral problems. Across the long-term follow-up from 12 to 36 months, Emotional Symptoms increased significantly and Conduct Problems stabilized. TBI was not a significant predictor of change during the chronic stage of recovery. Conclusions: After TBI, Emotional Symptoms and Conduct Problem scores were elevated, had different trajectories of change, increased or stayed elevated from 12 to 36 months after TBI, and did not return to pre-injury levels across the 3 year follow-up. These findings highlight the importance of addressing behavioral problems after TBI across an extended time frame

    Yours ever (well, maybe): Studies and signposts in letter writing

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    Electronic mail and other digital communications technologies seemingly threaten to end the era of handwritten and typed letters, now affectionately seen as part of snail mail. In this essay, I analyze a group of popular and scholarly studies about letter writing-including examples of pundits critiquing the use of e-mail, etiquette manuals advising why the handwritten letter still possesses value, historians and literary scholars studying the role of letters in the past and what it tells us about our present attitudes about digital communications technologies, and futurists predicting how we will function as personal archivists maintaining every document including e-mail. These are useful guideposts for archivists, providing both a sense of the present and the past in the role, value and nature of letters and their successors. They also provide insights into how such documents should be studied, expanding our gaze beyond the particular letters, to the tools used to create them and the traditions dictating their form and function. We also can discern a role for archivists, both for contributing to the literature about documents and in using these studies and commentaries, suggesting not a new disciplinary realm but opportunities for new interdisciplinary work. Examining a documentary form makes us more sensitive to both the innovations and traditions as it shifts from the analog to the digital; we can learn not to be caught up in hysteria or nostalgia about one form over another and archivists can learn about what they might expect in their labors to document society and its institutions. At one time, paper was part of an innovative technology, with roles very similar to the Internet and e-mail today. It may be that the shifts are far less revolutionary than is often assumed. Reading such works also suggests, finally, that archivists ought to rethink how they view their own knowledge and how it is constructed and used. © 2010 Springer Science+Business Media B.V

    Exploring Entrepreneurial Skills and Competencies in Farm Tourism

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    Diversification to farm tourism is increasingly seen as a viable development strategy to promote a more diverse and sustainable rural economy and to counter declining farm incomes. However, our understanding of the dynamics of the modern farm tourism business and the entrepreneurial and competitive skills farmers require in making the transition from agriculture to a diversified - and service based - enterprise remains limited. Hence, the aim of this paper is to explore the range of skills and competencies that farmers in the North West of England identify as important when adopting a diversification strategy to farm tourism. With the findings indicating that that whilst a range of managerial skills are valued by farmers, they lack many of the additional business and entrepreneurial competencies required for success. Moreover, this paper acknowledges the need to generate consensus on the requisite skill-set that farm tourism operators require, along with a need for a currently fragmented rural tourism literature to acknowledge the significance of rural entrepreneurship and the characteristics of successful farmers and farm tourism ventures

    Essentially English : Sherlock Holmes at the BBC

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    Sir Arthur Conan Doyle’s Sherlock Holmes stories, currently enjoying renewed popularity on television via the BBC’s Sherlock (2010- ), have been adapted for the screen countless times around the world. Arguably best remembered are Granada’s long-running strand with Jeremy Brett (1984-94), and the Universal film series of the 1940s, featuring Basil Rathbone and Nigel Bruce. Less frequently cited, however, are the two series produced by the BBC between 1965 and 1968, in which first Douglas Wilmer and later Peter Cushing took on the mantle of the Baker Street detective. Typically for the time – but against the wishes of the Conan Doyle estate - these programmes adopted a multi-camera studio model; a mode of production which made them less attractive to US networks than the single camera 35mm film output of commercial rivals such as ITC. Drawing upon material from the BBC’s Written Archives Centre, this article investigates the motivations underpinning the Corporation’s refusal to accommodate the estate’s exhortations to seek American co-production and utilise single camera filming, not least of which was the BBC’s stated desire to maintain the ‘essentially English’ quality of Sherlock Holmes. This decision would have significant repercussions for the series’ overseas saleability, and – despite impressive viewing figures and positive audience reaction at home in the UK – helped contribute to its ‘forgotten’ status with regard to the television canon

    iSchools and archival studies

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    Whispers and rumors about the iSchool movement lead some to fear that this represents yet another shift away from the valued traditions of library schools, threatening something far different than what library science pioneers ever envisioned. Predating the iSchool movement, however, were other programmatic shifts such as those that led to the formalization of graduate archival education. This essay argues that such evolution is essential to our future, as iSchools tackle the increasingly complex issues confronting a digital society. We consider the mission and history of iSchools and of archival studies, the basic elements and concepts of archival studies that are critical to iSchools, and the relationship between iSchools and the changing nature of personal and institutional archives. © 2009 Springer Science+Business Media B.V
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