755 research outputs found

    Development of an autonomous in situ instrument for stable and precise freshwater pH measurements

    Get PDF

    LAND RIGHTS AND INTRA-HOUSEHOLD EMPLOYMENT AND RESOURCE USE IN THE PERI-URBAN AREA OF BANJUL, THE GAMBIA

    Get PDF
    As part of cooperative research program examining factor markets in peri-urban areas of The Gambia (Banjul and Serekunda) to see if they are constraining agricultural growth and employment, particularly in the horticultural subsector, the household production survey reported in this study assesses inter- and intrahousehold issues of market access and constraints to land-improving investment and productivity. Implemented in 1993, survey is highly disaggregated by plot, gender, enterprise, and type of employment.Land tenure--Gambia--Banjul Region, Vendors and purchasers--Gambia--Banjul Region, Household production--Gambia, Research methods, Rural conditions--Gambia, Rural off-farm employment--Gambia, Income and wealth--Gambia, Land markets--Gambia, Tenure types, Traditional--Gambia, Labor and Human Capital, Land Economics/Use,

    Who Should be Interviewed in Surveys of Household Income?

    Get PDF
    This study tests the null hypothesis that it is sufficient to interview only the household head to obtain accurate information on household income. Results show that using a husband’s estimate of his wife’s income does not produce statistically reliable results for poverty analysis. Estimates of the wife’s income provided by the husband and wife are in agreement in only six percent of households. While limiting interviews to one person has the advantage of reducing the time and expense of household surveys, this appears detrimental in terms of accuracy, and may lead to incorrect conclusions on the determinants of poverty.Africa, gender, household dynamics, household surveys, Malawi, poverty, Agricultural Finance,

    The FUV spectrum of TW Hya. I. Observations of H2_2 Fluorescence

    Get PDF
    We observed the classical T Tauri star TW Hya with \textit{HST}/STIS using the E140M grating, from 1150--1700 \AA, with the E230M grating, from 2200--2900 \AA, and with \FUSE from 900--1180 \AA. Emission in 143 Lyman-band H2_2 lines representing 19 progressions dominates the spectral region from 1250--1650 \AA. The total H2_2 emission line flux is 1.94×10−121.94 \times 10^{-12} erg cm−2^{-2} s−1^{-1}, which corresponds to 1.90×10−41.90\times10^{-4} L⊙L_\odot at TW Hya's distance of 56 pc. A broad stellar \Lya line photoexcites the H2_2 from excited rovibrational levels of the ground electronic state to excited electronic states. The \ion{C}{2} 1335 \AA doublet, \ion{C}{3} 1175 \AA\ multiplet, and \ion{C}{4} 1550 \AA doublet also electronically excite H2_2. The velocity shift of the H2_2 lines is consistent with the photospheric radial velocity of TW Hya, and the emission is not spatially extended beyond the 0\farcs05 resolution of \textit{HST}. The H2_2 lines have an intrinsic FWHM of 11.91±0.1611.91\pm0.16 \kms. One H2_2 line is significantly weaker than predicted by this model because of \ion{C}{2} wind absorption. We also do not observe any H2_2 absorption against the stellar \Lya profile. From these results, we conclude that the H2_2 emission is more consistent with an origin in a disk rather than in an outflow or circumstellar shell. We also analyze the hot accretion-region lines (e.g., \ion{C}{4}, \ion{Si}{4}, \ion{O}{6}) of TW Hya, which are formed at the accretion shock, and discuss some reasons why Si lines appear significantly weaker than other TR region lines.Comment: accepted by ApJ, 42 pages -- 20 text, 11 figure

    Augmented Reality Technician Assistance Program

    Get PDF
    The Augmented Reality Technician Assistance Program is a proof-of-concept project for allowing a remote expert to communicate with and assist a field technician in completing procedures with which the technician may be unfamiliar. For example, an expert in Navy aircraft maintenance could advise an Air Force flight mechanic about performing repairs or maintenance on Navy aircraft. The end goal of our Cedarville computer science capstone project is to create an experimental prototype to deliver to the Air Force Research Laboratory. In our prototype the expert uses a Microsoft Surface Pro tablet to communicate via marked up still images with a Hololens-enabled field technician. As a wearable computer, the Hololens provides the technician a hands-free advantage over traditional devices, because it’s interface does not use typical input devices such as a mouse and keyboard. The advantage of the Surface Pro is that it allows the expert to mark up instructional images naturally with the stylus, providing better precision for the annotations

    Driving performance in older adults: Current measures, findings, and implications for roadway safety

    Get PDF
    BACKGROUND AND OBJECTIVES: Over 10,000 people a day turn 65 in the United States. For many older adults, driving represents an essential component of independence and is one of the most important factors in overall mobility. Recent survey studies in older adults suggest that up to 60% of older adult drivers with mild cognitive impairment, and up to 30% with dementia, continue to drive. The purpose of this review is to provide a comprehensive and detailed resource on the topics of cognition and driving for clinicians, researchers, and policymakers working on efforts related to older adult drivers. RESEARCH DESIGN AND METHODS: Publications on PubMed and Medline and discussions with experts working in geriatrics, technology, driving policy, psychology, and diverse aspects of driving performance were utilized to inform the current review. RESULTS: Research indicates that there is a complex and inverse correlation between multiple cognitive measures, driving performance, and risky driving behaviors. The fragmented nature of available peer-reviewed literature, and a reliance on correlative data, do not currently allow for the identification of the temporal and reciprocal nature of the interplay between cognition and driving endpoints. DISCUSSION AND IMPLICATIONS: There are currently no widely accepted definitions, conceptual models, or uniform set of analyses for conducting geriatric research that is focused on driving. Establishing conventions for conducting research that harmonizes the fields of geriatrics, cognition, and driving research is critical for the development of the evidence base that will inform clinical practice and road safety policy

    Renal artery calcified plaque associations with subclinical renal and cardiovascular disease

    Get PDF
    Renal artery calcified plaque associations with subclinical renal and cardiovascular disease.BackgroundThe prognostic significance of renal artery calcified plaque (RAC) and its relationship with renal function, albuminuria, and systemic atherosclerosis are unknown.MethodsCalcified atherosclerotic plaque was measured in the renal arteries of 96 unrelated Caucasian subjects with type 2 diabetes mellitus (DM) using four-channel multidetector–row computed tomography (MDCT4). Renal artery calcium was measured as the sum of ostial and main renal artery calcium scores. Participants also underwent MDCT scanning to measure coronary artery calcium (CAC), carotid artery calcium, common iliac artery calcium, infra-renal aorta calcium, and B-mode ultrasound to measure carotid artery intima-medial thickness (IMT). Spearman's rank correlation coefficients were used to assess associations between RAC and measures of subclinical renal and cardiovascular disease. Partial correlation coefficients were computed to adjust for the potential confounding effects of age, gender, body mass index (BMI), DM duration, smoking, and serum cholesterol and triglyceride levels.ResultsCharacteristics of the study group were 54% (52/96) female with a mean ± SD (median) age 62.8 ± 8.4 (62.5) years, DM duration 10.6 ± 6.3 (8.0) years, hemoglobin A1C 7.5 ± 1.5 (7.2)%, BMI 32.1 ± 6.3 (31.1) kg/m2, serum creatinine concentration 1.11 ± 0.18 (1.10) mg/dL, urine albumin:creatinine ratio (ACR) 105.3 ± 423.1 (17.6) mg/g, modified MDRD equation glomerular filtration rate (GFR) 64.3 ± 12.6 (63.6) mL/min, RAC 372 ± 799 (101), CAC 1819 ± 2594 (622), carotid artery calcium 264 ± 451 (72), and B-mode ultrasound carotid IMT 0.70 ± 0.12 (0.69) mm. Sixty-five percent of subjects (62/96) had detectable RAC. Renal artery calcium was significantly associated with CAC (r = 0.50, P < 0.0001), carotid artery calcium (r = 0.58, P < 0.0001), common iliac artery calcium (r = 0.45, P < 0.0001), infra-renal aorta calcium (r = 0.70, P < 0.0001), IMT (r = 0.40, P = 0.0004), diastolic blood pressure (r=-0.33, P = 0.0009), BMI (r=-0.19, P = 0.0573), and age (r = 0.54, P < 0.0001). There was no association between RAC and GFR (r=-0.15, P = 0.1637) or between RAC and urine ACR (r = 0.07, P = 0.5083).ConclusionRenal artery calcium is strongly associated with older age, diastolic blood pressure, BMI, carotid artery IMT, and coronary, carotid, common iliac artery, and infra-renal aorta calcium in Caucasians with type 2 diabetes mellitus. Renal artery calcium, similar to CAC and IMT, appears to be a useful noninvasive marker of subclinical atherosclerosis. However, RAC is not significantly associated with either GFR or albuminuria
    • 

    corecore