2,723 research outputs found

    Managing droughts in the low-rainfall areas of the Middle East and North Africa:

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    Drought is a recurrent and often devastating threat to the welfare of countries in the Middle East and North Africa (MENA) where three-quarters of the arable land has less than 400 mm of annual rainfall, and the natural grazings, which support a majority of the 290 million ruminant livestock, have less than 200 mm. Its impact has been exacerbated in the last half century by the human population increasing yearly at over 3%, while livestock numbers have risen by 50% over the quinquennium. Virtually no scope exists for further expansion of rainfed farming and very little for irrigation, hence there is competition between mechanized cereal production and grazing in the low rainfall areas, and traditional nomadic systems of drought management through mobility are becoming difficult to maintain. Moreover droughts seem to be increasing in frequency, and their high social, economic, and environmental costs have led governments to intervene with various forms of assistance to farmers and herders, including distribution of subsidized animal feed, rescheduling of loans, investments in water development, and in animal health. In this paper we examine the nature and significance of these measures, both with respect to their immediate benefits and costs to the recipients and to governments, and to their longer term impact on poverty and the environment. We conclude that while they have been valuable in reducing catastrophic losses of livestock and thus alleviating poverty, especially in the low rainfall areas where they are the predominant source of income, continued dependence on these programs has sent inappropriate signals to farmers and herders, leading to moral hazards, unsustainable farming practices, and environmental degradation, while generally benefiting the affluent recipients most.Rainfed farming., Environmental impact analysis., Irrigation., Droughts., Middle East., North Africa.,

    Lordship and Environmental Change in Central Highland Scotland c.1300–c.1400

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    Whilst there has been an increasing recognition of the infl uence of natural agency on human society in Scotland in the medieval period, conventional historiography has generally presented the wholesale reconfi guration of structures of secular lordship in the Scottish central Highlands in the 14th century as an essentially political consequence of the sociopolitical dislocation associated with the Anglo-Scottish wars that occurred after 1296. The establishment within the region of militarised Gaelic kindreds from the West Highlands and Hebrides of Scotland has come to be regarded as either a symptom of efforts by externally based regional lords to bolster their authority, or an opportunistic territorial aggrandisement by newly dominant neighbouring lords. Feuding and predatory raiding associated with these kindreds is recognised as competition for resources but generally in a context of projection of superior lordship over weaker neighbours. Evidence for long-term changes in climate extrapolated from North Atlantic proxy data, however, suggests that the cattle-based economy of Atlantic Scotland was experiencing protracted environmentally induced stress in the period c.1300–c.1350. Using this evidence, we discuss whether exchange systems operating within traditional lordship structures could offset localised and short-term pressures on the livestock-based regime, but could not be sustained long-term on the reduced fodder and contracting herd sizes caused by climatic deterioration. Territorial expansion and development of a predatory culture, it is argued, were responses to an environment-triggered economic crisis

    Patients' experiences of assessment and detention under mental health legislation: systematic review and qualitative meta-synthesis

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    Background Understanding patient experiences of detention under mental health legislation is crucial to efforts to reform policy and practice. Aims To synthesise qualitative evidence on patients' experiences of assessment and detention under mental health legislation. Method Five bibliographic databases were searched, supplemented by reference list screening and citation tracking. Studies were included if they reported on patient experiences of assessment or detention under mental health legislation; reported on patients aged 18 years or older; collected data using qualitative methods; and were reported in peer-reviewed journals. Findings were analysed and synthesised using thematic synthesis. Results The review included 56 papers. Themes were generally consistent across studies and related to information and involvement in care, the environment and relationships with staff, as well as the impact of detention on feelings of self-worth and emotional state. The emotional impact of detention and views of its appropriateness varied, but a frequent theme was fear and distress during detention, including in relation to the use of force and restraint. Where staff were perceived as striving to form caring and collaborative relationships with patients despite the coercive nature of treatment, and when clear information was delivered, the negative impact of involuntary care seemed to be reduced. Conclusions Findings suggest that involuntary in-patient care is often frightening and distressing, but certain factors were identified that can help reduce negative experiences. Coproduction models may be fruitful in developing new ways of working on in-patient wards that provide more voice to patients and staff, and physical and social environments that are more conducive to recovery

    Modelling marine emissions and atmospheric distributions of halocarbons and dimethyl sulfide: the influence of prescribed water concentration vs. prescribed emissions

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    Marine-produced short-lived trace gases such as dibromomethane (CH2Br2), bromoform (CHBr3), methyliodide (CH3I) and dimethyl sulfide (DMS) significantly impact tropospheric and stratospheric chemistry. Describing their marine emissions in atmospheric chemistry models as accurately as possible is necessary to quantify their impact on ozone depletion and Earth's radiative budget. So far, marine emissions of trace gases have mainly been prescribed from emission climatologies, thus lacking the interaction between the actual state of the atmosphere and the ocean. Here we present simulations with the chemistry climate model EMAC (ECHAM5/MESSy Atmospheric Chemistry) with online calculation of emissions based on surface water concentrations, in contrast to directly prescribed emissions. Considering the actual state of the model atmosphere results in a concentration gradient consistent with model real-time conditions at the ocean surface and in the atmosphere, which determine the direction and magnitude of the computed flux. This method has a number of conceptual and practical benefits, as the modelled emission can respond consistently to changes in sea surface temperature, surface wind speed, sea ice cover and especially atmospheric mixing ratio. This online calculation could enhance, dampen or even invert the fluxes (i.e. deposition instead of emissions) of very short-lived substances (VSLS). We show that differences between prescribing emissions and prescribing concentrations (−28 % for CH2Br2 to +11 % for CHBr3) result mainly from consideration of the actual, time-varying state of the atmosphere. The absolute magnitude of the differences depends mainly on the surface ocean saturation of each particular gas. Comparison to observations from aircraft, ships and ground stations reveals that computing the air–sea flux interactively leads in most of the cases to more accurate atmospheric mixing ratios in the model compared to the computation from prescribed emissions. Calculating emissions online also enables effective testing of different air–sea transfer velocity (k) parameterizations, which was performed here for eight different parameterizations. The testing of these different k values is of special interest for DMS, as recently published parameterizations derived by direct flux measurements using eddy covariance measurements suggest decreasing k values at high wind speeds or a linear relationship with wind speed. Implementing these parameterizations reduces discrepancies in modelled DMS atmospheric mixing ratios and observations by a factor of 1.5 compared to parameterizations with a quadratic or cubic relationship to wind spee

    High Purity Pion Beam at TRIUMF

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    An extension of the TRIUMF M13 low-energy pion channel designed to suppress positrons based on an energy-loss technique is described. A source of beam channel momentum calibration from the decay pi+ --> e+ nu is also described.Comment: 5 page

    Non-invasive methods for the estimation of mPAP in COPD using Cardiovascular Magnetic Resonance Imaging

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    Purpose Pulmonary hypertension (PH) is associated with a poor outcome in chronic obstructive pulmonary disease (COPD) and is diagnosed invasively. We aimed to assess the diagnostic accuracy and prognostic value of non-invasive cardiovascular magnetic resonance (CMR) models. Methods Patients with COPD and suspected PH, who underwent CMR and right heart catheter (RHC) were identified. Three candidate models were assessed: 1, CMR-RV model, based on right ventricular (RV) mass and interventricular septal angle; 2, CMR PA/RV includes RV mass, septal angle and pulmonary artery (PA) measurements; 3, the Alpha index, based on RV ejection fraction and PA size. Results Of 102 COPD patients, 87 had PH. The CMR-PA/RV model had the strongest diagnostic accuracy (sensitivity 92%, specificity 80%, positive predictive value 96% and negative predictive value 63%, AUC 0.93, p<0.0001). Splitting RHCmPAP, CMR-RV and CMR-PA/RV models by 35mmHg gave a significant difference in survival, with log-rank chi-squared 5.03, 5.47 and 7.10. RV mass and PA relative area change were the independent predictors of mortality at multivariate Cox regression (p=0.002 and 0.030). Conclusion CMR provides diagnostic and prognostic information in PH-COPD. The CMR-PA/RV model is useful for diagnosis, the RV mass index and PA relative area change are useful to assess prognosis. Key Points • Pulmonary hypertension is a marker of poor outcome in COPD. • MRI can predict invasively measured mean pulmonary artery pressure. • Cardiac MRI allows for estimation of survival in COPD. • Cardiac MRI may be useful for follow up or future trials. • MRI is potentially useful to assess pulmonary hypertension in patients with COPD
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