554 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%

    The Influence of Pregnancy on the Recurrence of Cutaneous Malignant Melanoma in Women

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    Objective. The aim of this study was to determine whether pregnancy increases the recurrence risk of cutaneous malignant melanoma (CMM) in women with a history of stage I CMM. Methods. The electronic medical databases of Medline and Embase were explored. All 1084 obtained articles were screened on title and abstract using predetermined inclusion and exclusion criteria. A critical appraisal of relevance and validity was conducted on the remaining full text available articles. Results. Two studies were selected. Both studies revealed no significant difference in disease-free survival between women with stage I CMM and the control population. Conclusion. Pregnancy does not increase the recurrence risk of CMM in women with a history of stage I CMM

    The utilization of ethanol by dairy cows

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    A preliminary study of the possibility of using large amounts of ethanol as an energy source for milking cows has been made. During the whole of the experimental period the cows were stall fed. Maximum blood ethanol levels were found ½—2 hours after dosing. Measurements of the rate of decrease of blood ethanol concentration, which is affected in part by elimination of ethanol in urine, milk and exhaled air, gave an apparent rate of oxidation in the animal organism (mean value for 4 cows) of 1.39 (range 0.75—1.59) kg per 500 kg live weight per 24 hr. During a 7-day experiment the cows’ drinking water contained about 1.4 % (w/v) ethanol. Their health did not appear to be affected adversely and blood glucose levels measured on the 7th day were normal. Milk yields decreased slightly at the beginning of the ethanol administration but then rose again during a period of a few days to pre-experiment levels. Drinking water containing 2 % ethanol caused clear intoxication in the cow which drank most (animal fell over). Administration of ethanol in the drinking water gave rise to a distinct off-flavour in the milk

    The Causes of Foehn Warming in the Lee of Mountains

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    The foehn effect is well known as the warming, drying, and cloud clearance experienced on the lee side of mountain ranges during “flow over” conditions. Foehn flows were first described more than a century ago when two mechanisms for this warming effect were postulated: an isentropic drawdown mechanism, where potentially warmer air from aloft is brought down adiabatically, and a latent heating and precipitation mechanism, where air cools less on ascent—owing to condensation and latent heat release—than on its dry descent on the lee side. Here, for the first time, the direct quantitative contribution of these and other foehn warming mechanisms is shown. The results suggest a new paradigm is required after it is demonstrated that a third mechanism, mechanical mixing of the foehn flow by turbulence, is significant. In fact, depending on the flow dynamics, any of the three warming mechanisms can dominate. A novel Lagrangian heat budget model, back trajectories, high-resolution numerical model output, and aircraft observations are all employed. The study focuses on a unique natural laboratory—one that allows unambiguous quantification of the leeside warming—namely, the Antarctic Peninsula and Larsen C Ice Shelf. The demonstration that three foehn warming mechanisms are important has ramifications for weather forecasting in mountainous areas and associated hazards such as ice shelf melt and wildfires

    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

    Accounting for risk in valuing forest carbon offsets

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    <p>Abstract</p> <p>Background</p> <p>Forests can sequester carbon dioxide, thereby reducing atmospheric concentrations and slowing global warming. In the U.S., forest carbon stocks have increased as a result of regrowth following land abandonment and in-growth due to fire suppression, and they currently sequester approximately 10% of annual US emissions. This ecosystem service is recognized in greenhouse gas protocols and cap-and-trade mechanisms, yet forest carbon is valued equally regardless of forest type, an approach that fails to account for risk of carbon loss from disturbance.</p> <p>Results</p> <p>Here we show that incorporating wildfire risk reduces the value of forest carbon depending on the location and condition of the forest. There is a general trend of decreasing risk-scaled forest carbon value moving from the northern toward the southern continental U.S.</p> <p>Conclusion</p> <p>Because disturbance is a major ecological factor influencing long-term carbon storage and is often sensitive to human management, carbon trading mechanisms should account for the reduction in value associated with disturbance risk.</p
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