3,837 research outputs found

    Cohousing for older people: Housing innovation in the Netherlands and Denmark

    Get PDF
    Objective: The aim of this paper is to elucidate cohousing for older people. Method: The research is based on a literature review and interviews (in English) with residents of seven schemes in the Netherlands and Denmark, a social housing organisation and several researchers in the field (in 1995 and 2002). Results and Conclusions: Cohousing for older people is now well established in its countries of origin - Denmark and the Netherlands - as a way for older people to live in their own house or unit, with a self-chosen group of other older people as neighbours, with shared space and facilities they collectively determine or control. As more such housing is built and occupied it has become easier to choose and assess this option. It remains to be seen how widespread its appeal will be, but cohousing for older people is now a valued housing niche

    A comparison of GC-FID and PTR-MS toluene measurements in ambient air under conditions of enhanced monoterpene loading

    Get PDF
    Toluene was measured using both a gas chromatographic system (GC), with a flame ionization detector (FID), and a proton transfer reaction-mass spectrometer (PTR-MS) at the AIRMAP atmospheric monitoring station Thompson Farm (THF) in rural Durham, NH during the summer of 2004. Simultaneous measurements of monoterpenes, including alpha- and beta-pinene, camphene, Delta(3)-carene, and d-limonene, by GC-FID demonstrated large enhancements in monoterpene mixing ratios relative to toluene, with median and maximum enhancement ratios of similar to 2 and similar to 30, respectively. A detailed comparison between the GC-FID and PTR-MS toluene measurements was conducted to test the specificity of PTR-MS for atmospheric toluene measurements under conditions often dominated by biogenic emissions. We derived quantitative estimates of potential interferences in the PTR-MS toluene measurements related to sampling and analysis of monoterpenes, including fragmentation of the monoterpenes and some of their primary carbonyl oxidation products via reactions with H(3)O(+), O(2)(+) and NO(+) in the PTR-MS drift tube. The PTR-MS and GC-FID toluene measurements were in good quantitative agreement and the two systems tracked one another well from the instrumental limits of detection to maximum mixing ratios of similar to 0.5 ppbv. A correlation plot of the PTR-MS versus GC-FID toluene measurements was described by the least squares regression equation y=(1.13 +/- 0.02)x-(0.008 +/- 0.003) ppbv, suggesting a small similar to 13% positive bias in the PTR-MS measurements. The bias corresponded with a similar to 0.055 ppbv difference at the highest measured toluene level. The two systems agreed quantitatively within the combined 1 sigma measurement precisions for 60% of the measurements. Discrepancies in the measured mixing ratios were not well correlated with enhancements in the monoterpenes. Better quantitative agreement between the two systems was obtained by correcting the PTR-MS measurements for contributions from monoterpene fragmentation in the PTR-MS drift tube; however, the improvement was minor (\u3c10%). Interferences in the PTRMS measurements from fragmentation of the monoterpene oxidation products pinonaldehyde, caronaldehyde and alpha-pinene oxide were also likely negligible. A relatively large and variable toluene background in the PTR-MS instrument likely drove the measurement bias; however, the precise contribution was difficult to accurately quantify and thus was not corrected for in this analysis. The results from THF suggest that toluene can be reliably quantified by PTR-MS using our operating conditions (drift tube pressure, temperature and voltage of 2.0 mbar, 45 degrees C and 600V, respectively) under the ambient compositions probed. This work extends the range of field conditions under which PTR-MS validation studies have been conducted

    Measuring the quantum efficiency of single radiating dipoles using a scanning mirror

    Full text link
    Using scanning probe techniques, we show the controlled manipulation of the radiation from single dipoles. In one experiment we study the modification of the fluorescence lifetime of a single molecular dipole in front of a movable silver mirror. A second experiment demonstrates the changing plasmon spectrum of a gold nanoparticle in front of a dielectric mirror. Comparison of our data with theoretical models allows determination of the quantum efficiency of each radiating dipole.Comment: 4 pages, 4 figure

    Bromoform and dibromomethane measurements in the seacoast region of New Hampshire, 2002–2004

    Get PDF
    Atmospheric measurements of bromoform (CHBr3) and dibromomethane (CH2Br2) were conducted at two sites, Thompson Farm (TF) in Durham, New Hampshire (summer 2002–2004), and Appledore Island (AI), Maine (summer 2004). Elevated mixing ratios of CHBr3 were frequently observed at both sites, with maxima of 37.9 parts per trillion by volume (pptv) and 47.4 pptv for TF and AI, respectively. Average mixing ratios of CHBr3 and CH2Br2 at TF for all three summers ranged from 5.3–6.3 and 1.3–2.3 pptv, respectively. The average mixing ratios of both gases were higher at AI during 2004, consistent with AI\u27s proximity to sources of these bromocarbons. Strong negative vertical gradients in the atmosphere corroborated local sources of these gases at the surface. At AI, CHBr3 and CH2Br2 mixing ratios increased with wind speed via sea‐to‐air transfer from supersaturated coastal waters. Large enhancements of CHBr3 and CH2Br2 were observed at both sites from 10 to 14 August 2004, coinciding with the passage of Tropical Storm Bonnie. During this period, fluxes of CHBr3 and CH2Br2 were 52.4 ± 21.0 and 9.1 ± 3.1 nmol m−2 h−1, respectively. The average fluxes of CHBr3 and CH2Br2 during nonevent periods were 18.9 ± 12.3 and 2.6 ± 1.9 nmol m−2 h−1, respectively. Additionally, CHBr3 and CH2Br2 were used as marine tracers in case studies to (1) evaluate the impact of tropical storms on emissions and distributions of marine‐derived gases in the coastal region and (2) characterize the transport of air masses during pollution episodes in the northeastern United States

    Rare Kaon Decays

    Get PDF
    The current status of rare kaon decay experiments is reviewed. New limits in the search for Lepton Flavor Violation are discussed, as are new measurements of the CKM matrix.Comment: 8 pages, 3 figures, LaTeX, presented at the 3rd International Conference on B Phyiscs and CP Violation, Taipei December 3-7, 199

    The Design and Validation of the Quantum Mechanics Conceptual Survey

    Full text link
    The Quantum Mechanics Conceptual Survey (QMCS) is a 12-question survey of students' conceptual understanding of quantum mechanics. It is intended to be used to measure the relative effectiveness of different instructional methods in modern physics courses. In this paper we describe the design and validation of the survey, a process that included observations of students, a review of previous literature and textbooks and syllabi, faculty and student interviews, and statistical analysis. We also discuss issues in the development of specific questions, which may be useful both for instructors who wish to use the QMCS in their classes and for researchers who wish to conduct further research of student understanding of quantum mechanics. The QMCS has been most thoroughly tested in, and is most appropriate for assessment of (as a posttest only), sophomore-level modern physics courses. We also describe testing with students in junior quantum courses and graduate quantum courses, from which we conclude that the QMCS may be appropriate for assessing junior quantum courses, but is not appropriate for assessing graduate courses. One surprising result of our faculty interviews is a lack of faculty consensus on what topics should be taught in modern physics, which has made designing a test that is valued by a majority of physics faculty more difficult than expected.Comment: Submitted to Physical Review Special Topics: Physics Education Researc

    Robonaut Mobile Autonomy: Initial Experiments

    Get PDF
    A mobile version of the NASA/DARPA Robonaut humanoid recently completed initial autonomy trials working directly with humans in cluttered environments. This compact robot combines the upper body of the Robonaut system with a Segway Robotic Mobility Platform yielding a dexterous, maneuverable humanoid ideal for interacting with human co-workers in a range of environments. This system uses stereovision to locate human teammates and tools and a navigation system that uses laser range and vision data to follow humans while avoiding obstacles. Tactile sensors provide information to grasping algorithms for efficient tool exchanges. The autonomous architecture utilizes these pre-programmed skills to form complex behaviors. The initial behavior demonstrates a robust capability to assist a human by acquiring a tool from a remotely located individual and then following the human in a cluttered environment with the tool for future use

    Study on the role of microfinance on indebtedness in marine fisheries sector in Odisha

    Get PDF
    The microfinance organizations and self help groups mobilised in marine fisheries sector play vital role in reducing the indebtedness among marine fisherfolk. The study makes an attempt on the assessment of the extent of indebtedness among marine fisherfolk in mechanized, motorized and traditional fisheries sectors and the impact assessment of Microfinance Institutions (MFI) on coastal indebtedness. The study was carried out in four coastal districts of Odisha state. Situational analysis was done through PLA in the selected locations and the sample respondents were selected from mechanized, motorized and traditional sectors. Data were collected through personal interview from members of 12 selected MFIs and non members in these sectors comprising a total of 600 respondents. The results showed that the level of indebtedness of members of MFIs was less compared to the non members. Even if the indebtedness was more in certain cases, the repayment capacity was found to be significantly improved in MFIs. There is an extreme necessity for strengthening the MFI ventures in the traditional and tertiary fisheries sectors in the state. A comparative assessment of the sources of credit, purposes of credit and utilization pattern of loans in the state also was undertaken to draw valid conclusions. It was also found that the MFIs ranked better in most of the major attributes in the perception of stakeholders compared to banks and non-institutional credit sources. Success cases of MFIs on entrepreneurial capacity building, those significantly played the role in the debt redemption and poverty alleviation were documented as a practical manual for mobilizing MFIs in any key areas on a sustainable basis

    Cigar Smoking Among U.S. Students: Reported Use After Adding Brands to Survey Items

    Get PDF
    Background: Among U.S. youth overall, cigars are the most commonly used tobacco product after cigarettes. However, youth who identify their products by brand names, not general terms like “cigar,” may underreport use. Purpose: To examine changes in reported cigar (cigar, cigarillo, or little cigar) smoking among students following inclusion of cigar brand examples on the National Youth Tobacco Survey (NYTS). Methods: Data from the 2011 and 2012 NYTS and National Survey on Drug Use and Health (NSDUH) were analyzed in 2013 to estimate ever and current cigar smoking, overall and by race/ ethnicity. The 2012 NYTS included cigar brand examples (Black and Mild, Swisher Sweets, Dutch Masters, White Owl, Phillies Blunt) in the survey instructions and ever use question, but the 2011 NYTS and 2011 and 2012 NSDUH did not. Results: NYTS ever cigar smoking was higher in 2012 (27.8%) than 2011 (19.5%) among black students overall. Current cigar smoking was 60%–70% higher among black females and students agedZ17 years, in 2012 than 2011. For black females, current cigar smoking (11.5%) was two times greater than that of white females (4.3%) in 2012, whereas the prevalence among these subgroups was comparable in 2011. Similar changes were not observed among these subgroups in the 2011– 2012 NSDUH. Conclusions: This study highlights the high burden of cigar use among U.S. youth and suggests that NYTS ascertainment of cigar smoking may have improved by including brands. Disparities in cigar smoking need to be addressed to prevent and reduce all youth tobacco use. (Am J Prev Med 2014;47(2S1):S28–S35) Published by Elsevier Inc. on behalf of American Journal of Preventive Medicin
    corecore