833 research outputs found

    Poly[[tri-μ-cyanido-cyanido(1,4,10,13-tetra­oxa-7,16-diaza­cyclo­octa­deca­ne)barium(II)platinum(II)] hemihydrate]

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    The title compound, {[BaPt(CN)4(C12H26N2O4)]·0.5H2O}n, is a two-dimensional coordination polymer in which the sheets are oriented approximately parallel to the (01) set of crystal planes. In the crystal structure, disordered water mol­ecules (half occupancy) connect the sheets into a three-dimensional network via inter­molecular O—H⋯O hydrogen bonds. An N—H⋯N inter­action is also present. The shortest Pt⋯Pt contacts are 7.5969 (4) Å by an inversion relationship and 7.6781 (4) Å by translation along the a axis

    Combining the bulk transfer formulation and surface renewal analysis for estimating the sensible heat flux without involving the parameter KB-1

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    The single‐source bulk transfer formulation (based on the Monin‐Obukhov Similarity Theory, MOST) has been used to estimate the sensible heat flux, H, in the framework of remote sensing over homogeneous surfaces (HMOST). The latter involves the canopy parameter, , which is difficult to parameterize. Over short and dense grass at a site influenced by regional advection of sensible heat flux, HMOST with  = 2 (i.e., the value recommended) correlated strongly with the H measured using the Eddy Covariance, EC, method, HEC. However, it overestimated HEC by 50% under stable conditions for samples showing a local air temperature gradient larger than the measurement error, 0.4 km−1. Combining MOST and Surface Renewal analysis, three methods of estimating H that avoid dependency have been derived. These new expressions explain the variability of H versus , where is the friction velocity, is the radiometric surface temperature, and is the air temperature at height, z. At two measurement heights, the three methods performed excellently. One of the methods developed required the same readily/commonly available inputs as HMOST due to the fact that the ratio between and the ramp amplitude was found fairly constant under stable and unstable cases. Over homogeneous canopies, at a site influenced by regional advection of sensible heat flux, the methods proposed are an alternative to the traditional bulk transfer method because they are reliable, exempt of calibration against the EC method, and are comparable or identical in cost of application. It is suggested that the methodology may be useful over bare soil and sparse vegetation.This research was funded by CERESS project AGL2011–30498 (Ministerio de Economía y Competitividad of Spain, cofunded FEDER), CGL2012–37416‐C04‐01 (Ministerio de Ciencia y Innovación of Spain), and CEI Iberus, 2014 (Proyecto financiado por el Ministerio de Educación en el marco del Programa Campus de Excelencia Internacional of Spain)

    Monomers, dimers, and trimers of [Au(CN)2]− in a Ba(diaza-18-crown-6)2+ coordination polymer

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    The structure of the title compound, poly[triaquatetra-μ-cyanido-tetracyanidobis­(1,4,10,13-tetra­oxa-7,16-diaza­cyclo­octa­deca­ne)di­barium(II)tetra­gold(I)], [Au4Ba2(CN)8(C12H26N2O4)2(H2O)3]n, displays O—H⋯N hydrogen bonding between water molecules and cyano ligands and an unusual pattern of aurophilic inter­actions that yields a monomer, dimer, and trimer of [Au(CN)2]− within the same crystal structure. In two of the five Au positions, the atom resides on a center of inversion. The overall arrangement is that of a coordination polymer assisted by aurophilic and hydrogen-bonded inter­actions

    Modeling Regional Carbon Dioxide Flux over California using the WRF‑ACASA Coupled Model

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    Many processes and interactions in the atmosphere and the biosphere influence the rate of carbon dioxide exchange between these two systems. However, it is difficult to estimate the carbon dioxide flux over regions with diverse ecosystems and complex terrains, such as California. Traditional carbon dioxide measurements are sparse and limited to specific ecosystems. Therefore, accurately estimating carbon dioxide flux on a regional scale remains a major challenge. In this study, we couple the Weather Research and Forecasting Model (WRF) with the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA), a high complexity land surface model. Although WRF is a state-of-the-art regional atmospheric model with high spatial and temporal resolutions, the land surface schemes available in WRF lack the capability to simulate carbon dioxide. ACASA is a complex multilayer land surface model with interactive canopy physiology and full surface hydrological processes. It allows microenvironmental variables such as air and surface temperatures, wind speed, humidity, and carbon dioxide concentration to vary vertically. Carbon dioxide, sensible heat, water vapor, and momentum fluxes between the atmosphere and land surface are estimated in the ACASA model through turbulence equations with a third order closure scheme. It therefore permits counter-gradient transports that low-order turbulence closure models are unable to simulate. A new CO2 tracer module is introduced into the model framework to allow the atmospheric carbon dioxide concentration to vary according to terrestrial responses. In addition to the carbon dioxide simulation, the coupled WRF-ACASA model is also used to investigate the interactions of neighboring ecosystems in their response to atmospheric carbon dioxide concentration. The model simulations with and without the CO2 tracer for WRF-ACASA are compared with surface observations from the AmeriFlux network.This work is supported in part by the National Science Foundation under Awards No.ATM-0619139 and EF-1137306. The Joint Program on the Science and Policy of Global Change is funded by a number of federal agencies and a consortium of 40 industrial and foundation sponsors. (For the complete list see http://globalchange.mit.edu/sponsors/current.html)

    Effects of resistance and functional-skills training on habitual activity and constipation among older adults living in long-term care facilities: a randomized controlled trial

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    BACKGROUND: Large-scale RCTs comparing different types of exercise training in institutionalised older people are scarce, especially regarding effects on habitual physical activity and constipation. This study investigated the effects of different training protocols on habitual physical activity and constipation of older adults living in long-term care facilities. METHODS: A randomized controlled trial with 157 participants, aged 64 to 94 years, who were randomly assigned to 1) resistance training; 2) all-round functional-skills training; 3) both; or 4) an 'educational' control condition. Habitual physical activity was assessed with a physical activity questionnaire and accelerometers. Constipation was assessed by a questionnaire. Measurements were performed at baseline and after six months of training. RESULTS: At baseline the median time spent sitting was 8.2 hr/d, the median time spent on activity of at least moderate intensity was 32 min/d. At baseline, about 22% of the subjects were diagnosed with constipation and 23% were taking laxatives. There were no between-group differences for changes in habitual physical activity or constipation over 6-months. CONCLUSION: Six months of moderate intensity exercise training neither enhances habitual physical activity nor affects complaints of constipation among older people living in long-term care facilities

    Effects of resistance and all-round, functional training on quality of life, vitality and depression of older adults living in long-term care facilities: a 'randomized' controlled trial [ISRCTN87177281]

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    BACKGROUND: Regular physical activity may improve different aspects of wellbeing in older people, such as quality of life, vitality and depression. However, there is little experimental evidence to support this assumption. Therefore, we examined the effect of different training protocols on quality of life, vitality and depression of older adults living in long-term care facilities. METHODS: Subjects (n = 173, aged 64 to 94 years, living in long-term care facilities), were randomized to six months of three different moderate-intensity group exercise training protocols, or to an 'educational' control condition. Exercise consisted of two 45–60-minute training sessions per week of 1) resistance training; 2) all-round, functional training; or 3) a combination of both. Perceived health, the Geriatric Depression Scale (GDS), the Vitality Plus Scale (VPS) and the Dementia Quality of Life questionnaire (DQoL) were administered at baseline and after six months. RESULTS: In the combined training group a small but significant decline was seen in perceived health, DQoL and VPS score compared to the control group. CONCLUSIONS: We conclude that neither strength training nor all-round, functional training of moderate intensity is effective in improving quality of life, vitality or depression of older people living in long-term care facilities
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