289 research outputs found

    Future humidity trends over the western United States in the CMIP5 global climate models and variable infiltration capacity hydrological modeling system

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    Global climate models predict relative humidity (RH) in the western US will decrease at a rate of about 0.1–0.6 percentage points per decade, albeit with seasonal differences (most drying in spring and summer), geographical variability (greater declines in the interior), stronger reductions for greater anthropogenic radiative forcing, and notable spread among the models. Although atmospheric moisture content increases, this is more than compensated for by higher air temperatures, leading to declining RH. Fine-scale hydrological simulations driven by the global model results should reproduce these trends. It is shown that the MT-CLIM meteorological algorithms used by the Variable Infiltration Capacity (VIC) hydrological model, when driven by daily Tmin, Tmax, and precipitation (a configuration used in numerous published studies), do not preserve the original global model\u27s humidity trends. Trends are biased positive in the interior western US, so that strong RH decreases are changed to weak decreases, and weak decreases are changed to increases. This happens because the MT-CLIM algorithms VIC incorporates infer an overly large positive trend in atmospheric moisture content in this region, likely due to an underestimate of the effect of increasing aridity on RH. The result could downplay the effects of decreasing RH on plants and wildfire. RH trends along the coast have a weak negative bias due to neglect of the ocean\u27s moderating influence. A numerical experiment where the values of Tdew are altered to compensate for the RH error suggests that eliminating the atmospheric moisture bias could, in and of itself, decrease runoff up to 14% in high-altitude regions east of the Sierra Nevada and Cascades, and reduce estimated Colorado River runoff at Lees Ferry up to 4% by the end of the century. It could also increase the probability of large fires in the northern and central US Rocky Mountains by 13 to 60%

    Behavioral adaptation to climate change in wildfireâ prone forests

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146375/1/wcc553.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146375/2/wcc553_am.pd

    The socio-technical organisation of community pharmacies as a factor in the Electronic Prescription Service Release Two implementation: a qualitative study

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    Background The introduction of a new method of transmitting prescriptions from general practices to community pharmacies in England (Electronic Prescription Service Release 2 (EPS2)) has generated debate on how it will change work practice. As EPS2 will be a key technical element in dispensing, we reviewed the literature to find that there were no studies on how social and technical elements come together to form work practice in community pharmacies. This means the debate has little point of reference. Our aim therefore was to study the ways social and technical elements of a community pharmacy are used to achieve dispensing through the development of a conceptual model on pharmacy work practice, and to consider how a core technical element such the EPS2 could change work practice. Method We used ethnographic methods inclusive of case-study observations and interviews to collect qualitative data from 15 community pharmacies that were in the process of adopting or were soon to adopt EPS2. We analysed the case studies thematically and used rigorous multi-dimensional and multi-disciplinary interpretive validation techniques to cross analyse findings. Results In practice, dispensing procedures were not designed to take into account variations in human and technical integration, and assumed that repetitive and collective use of socio-technical elements were at a constant. Variables such as availability of social and technical resources, and technical know-how of staff were not taken into account in formalised procedures. Yet community pharmacies were found to adapt their dispensing in relation to the balance of social and technical elements available, and how much of the social and technical elements they were willing to integrate into dispensing. While some integrated as few technical elements as possible, some depended entirely on technical artefacts. This pattern also applied to the social elements of dispensing. Through the conceptual model development process, we identified three approaches community pharmacies used to appropriate procedures in practice. These were ‘technically oriented’, ‘improvising’ or ‘socially oriented’. Conclusion We offer a model of different work approaches community pharmacies use to dispense, which suggests that when adopting a core technical element such as the EPS2 system of dispensing there could be variations in its successful adoption. Technically oriented pharmacies might find it easiest to integrate a similar artefact into work practice although needs EPS2 to synchronise effectively with existing technologies. Pharmacies adopting an improvising-approach have the potential to improve how they organise dispensing through EPS2 although they will need to improve how they apply their operating procedures. Socially oriented pharmacies will need to dramatically adapt their approach to dispensing since they usually rely on few technical tools

    The structure of quality systems is important to the process and outcome, an empirical study of 386 hospital departments in Sweden

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    <p>Abstract</p> <p>Background</p> <p>Clinicians, nurses, and managers in hospitals are continuously confronted by new technologies and methods that require changes to working practice. Quality systems can help to manage change while maintaining a high quality of care. A new model of quality systems inspired by the works of Donabedian has three factors: structure (resources and administration), process (culture and professional co-operation), and outcome (competence development and goal achievement). The objectives of this study were to analyse whether structure, process, and outcome can be used to describe quality systems, to analyse whether these components are related, and to discuss implications.</p> <p>Methods</p> <p>A questionnaire was developed and sent to a random sample of 600 hospital departments in Sweden. The adjusted response rate was 75%. The data were analysed with confirmatory factor analysis and structural equation modeling in LISREL. This is to our knowledge the first large quantitative study that applies Donabedian's model to quality systems.</p> <p>Results</p> <p>The model with relationships between structure, process, and outcome was found to be a reasonable representation of quality systems at hospital departments (p = 0.095, indicating no significant differences between the model and the data set). Structure correlated strongly with process (0.72) and outcome (0.60). Given structure, process also correlated with outcome (0.20).</p> <p>Conclusion</p> <p>The model could be used to describe and evaluate single quality systems or to compare different quality systems. It could also be an aid to implement a systematic and evidence-based system for working with quality improvements in hospital departments.</p

    SN 2023ixf in Messier 101: Photo-ionization of Dense, Close-in Circumstellar Material in a Nearby Type II Supernova

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    We present UV/optical observations and models of supernova (SN) 2023ixf, a type II SN located in Messier 101 at 6.9 Mpc. Early-time ("flash") spectroscopy of SN 2023ixf, obtained primarily at Lick Observatory, reveals emission lines of H I, He I/II, C IV, and N III/IV/V with a narrow core and broad, symmetric wings arising from the photo-ionization of dense, close-in circumstellar material (CSM) located around the progenitor star prior to shock breakout. These electron-scattering broadened line profiles persist for \sim8 days with respect to first light, at which time Doppler broadened features from the fastest SN ejecta form, suggesting a reduction in CSM density at r1015r \gtrsim 10^{15} cm. The early-time light curve of SN2023ixf shows peak absolute magnitudes (e.g., Mu=18.6M_{u} = -18.6 mag, Mg=18.4M_{g} = -18.4 mag) that are 2\gtrsim 2 mag brighter than typical type II supernovae, this photometric boost also being consistent with the shock power supplied from CSM interaction. Comparison of SN 2023ixf to a grid of light curve and multi-epoch spectral models from the non-LTE radiative transfer code CMFGEN and the radiation-hydrodynamics code HERACLES suggests dense, solar-metallicity, CSM confined to r=(0.51)×1015r = (0.5-1) \times 10^{15} cm and a progenitor mass-loss rate of M˙=102\dot{M} = 10^{-2} M_{\odot}yr1^{-1}. For the assumed progenitor wind velocity of vw=50v_w = 50 km s1^{-1}, this corresponds to enhanced mass-loss (i.e., ``super-wind'' phase) during the last \sim3-6 years before explosion.Comment: 18 pages, 8 figures. Submitted to ApJ

    Cause-specific mortality time series analysis: a general method to detect and correct for abrupt data production changes

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    <p>Abstract</p> <p>Background</p> <p>Monitoring the time course of mortality by cause is a key public health issue. However, several mortality data production changes may affect cause-specific time trends, thus altering the interpretation. This paper proposes a statistical method that detects abrupt changes ("jumps") and estimates correction factors that may be used for further analysis.</p> <p>Methods</p> <p>The method was applied to a subset of the AMIEHS (Avoidable Mortality in the European Union, toward better Indicators for the Effectiveness of Health Systems) project mortality database and considered for six European countries and 13 selected causes of deaths. For each country and cause of death, an automated jump detection method called Polydect was applied to the log mortality rate time series. The plausibility of a data production change associated with each detected jump was evaluated through literature search or feedback obtained from the national data producers.</p> <p>For each plausible jump position, the statistical significance of the between-age and between-gender jump amplitude heterogeneity was evaluated by means of a generalized additive regression model, and correction factors were deduced from the results.</p> <p>Results</p> <p>Forty-nine jumps were detected by the Polydect method from 1970 to 2005. Most of the detected jumps were found to be plausible. The age- and gender-specific amplitudes of the jumps were estimated when they were statistically heterogeneous, and they showed greater by-age heterogeneity than by-gender heterogeneity.</p> <p>Conclusion</p> <p>The method presented in this paper was successfully applied to a large set of causes of death and countries. The method appears to be an alternative to bridge coding methods when the latter are not systematically implemented because they are time- and resource-consuming.</p

    Estimates of CO2 from fires in the United States: implications for carbon management

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    <p>Abstract</p> <p>Background</p> <p>Fires emit significant amounts of CO<sub>2 </sub>to the atmosphere. These emissions, however, are highly variable in both space and time. Additionally, CO<sub>2 </sub>emissions estimates from fires are very uncertain. The combination of high spatial and temporal variability and substantial uncertainty associated with fire CO<sub>2 </sub>emissions can be problematic to efforts to develop remote sensing, monitoring, and inverse modeling techniques to quantify carbon fluxes at the continental scale. Policy and carbon management decisions based on atmospheric sampling/modeling techniques must account for the impact of fire CO<sub>2 </sub>emissions; a task that may prove very difficult for the foreseeable future. This paper addresses the variability of CO<sub>2 </sub>emissions from fires across the US, how these emissions compare to anthropogenic emissions of CO<sub>2 </sub>and Net Primary Productivity, and the potential implications for monitoring programs and policy development.</p> <p>Results</p> <p>Average annual CO<sub>2 </sub>emissions from fires in the lower 48 (LOWER48) states from 2002–2006 are estimated to be 213 (± 50 std. dev.) Tg CO<sub>2 </sub>yr<sup>-1 </sup>and 80 (± 89 std. dev.) Tg CO<sub>2 </sub>yr<sup>-1 </sup>in Alaska. These estimates have significant interannual and spatial variability. Needleleaf forests in the Southeastern US and the Western US are the dominant source regions for US fire CO<sub>2 </sub>emissions. Very high emission years typically coincide with droughts, and climatic variability is a major driver of the high interannual and spatial variation in fire emissions. The amount of CO<sub>2 </sub>emitted from fires in the US is equivalent to 4–6% of anthropogenic emissions at the continental scale and, at the state-level, fire emissions of CO<sub>2 </sub>can, in some cases, exceed annual emissions of CO<sub>2 </sub>from fossil fuel usage.</p> <p>Conclusion</p> <p>The CO<sub>2 </sub>released from fires, overall, is a small fraction of the estimated average annual Net Primary Productivity and, unlike fossil fuel CO<sub>2 </sub>emissions, the pulsed emissions of CO<sub>2 </sub>during fires are partially counterbalanced by uptake of CO<sub>2 </sub>by regrowing vegetation in the decades following fire. Changes in fire severity and frequency can, however, lead to net changes in atmospheric CO<sub>2 </sub>and the short-term impacts of fire emissions on monitoring, modeling, and carbon management policy are substantial.</p
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