122 research outputs found
Food security for sub-Saharan Africa: does water scarcity limit the options?
Future food security can be achieved only by delivering substantial increases in agricultural production, but this has important implications for water availability. Water scarcity is not currently a major issue in sub-Saharan Africa, but it would be a mistake to neglect this issue. It would be a mistake also to assume that only plans for irrigated agriculture are affected. It should be recognised that a land-use decision is also a water-use decision. A plan based on improving rain-fed agriculture through adoption of measures to make better use of rainfall brings trade-offs in that there may be less runoff to satisfy the water needs of downstream users and environmental functions. Planning for future food security requires integrated analysis of land-use and water resources issues.food security, water scarcity, irrigation, agriculture, Africa, Resource /Energy Economics and Policy,
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Development of rapid techniques based on selective dissolution for the determination of the precious metals in geological samples
The development of a rapid analytical technique for the determination of the platinumgroup elements (PGE) and gold in geological samples is described. The technique is based on selective aqua regia acid leach followed by a selective extraction (using diphenylthiourea and 1,2-dichloroethane) to separate the PGE and Au as a group from concomitant matrix elements. Organic extracts and aqueous raffinates were analysed by graphite furnace atomic absorption spectrometry, for which a comprehensive assessment of matrix interference effects was undertaken. Direct analysis of the aqua regia acid leachates by inductively coupled plasma-mass spectrometry (ICP-MS) was also evaluated. A number of other techniques were used to evaluate recoveries following acid attack, including x-ray fluorescence spectrometry and instrumental neutron activation analysis of solid residues and beta-autoradiography of thin sections to characterise PGE mineral solubility.
The results of these investigations identified optimum conditions for aqua regia extraction (20 ml of normal (3: 1) aqua regia for a 10 g sample, stirring for two hours at room temperature) and that quantitative recoveries can be expected for Au and semiquantitative for Pd with lower, but variable recoveries for Pt, Rh, Ru and Os and very low recovery of Ir. The solvent extraction procedure was effective in selectively extracting Au and Rh but was not quantitative in the extraction of Pt, Pd and Ru, the extraction of which appeared to be influenced by the sample matrix.
Further studies on the solubility in aqua regia of individual PGE minerals indicated that the main control of aqua regia extraction efficiency was sample mineralogy. The aqua regia leach procedure was applied to a range of samples that had been independently analysed by NiS fire assay as well as appropriate reference materials. This extraction procedure, with direct analysis of leachates by ICP-MS, was also used as the primary technique for characterising the homogeneity of two new chromitite reference materials, CHR-Pt+ and CHR-Bkg
Dealing with messy problems: lessons from water harvesting systems for crop production in Burkina Faso
Despite the identification of areas exhibiting successful adoption and use of water harvesting technologies (WHTs) by small-scale farmers in SSA, on the whole WHT use remains low and hence impacts on crop production and livelihoods marginal. Past research has determined the importance of social factors in the adoption and use of WHTs, but little attempt has been made to fully understand their role. This paper presents qualitative, micro level research conducted in Botswana and Burkina Faso that has increased understanding of the effect of social factors. The main lesson learnt is that WHTs sit within a highly complex and dynamic system and the problem of low adoption and use cannot be solved using approaches that attempt to over-simplify it. Ensuring the sustainability of WHTs into the future requires that the complexity and messiness of the system is fully embraced by researchers and practitioners seeking solutions
The terrestrial landscapes of tetrapod evolution in earliest Carboniferous seasonal wetlands of SE Scotland
The Lower Mississippian (Tournaisian) Ballagan Formation in SE Scotland yields tetrapod fossils that provide fresh insights into the critical period when these animals first moved onto land. The key to understanding the palaeoenvironments where they lived is a detailed analysis of the sedimentary architecture of this formation, one of the thickest and most completely documented examples of a coastal floodplain and marginal marine succession from this important transitional time anywhere in the world. Palaeosols are abundant, providing a unique insight into the early Carboniferous habitats and climate.
More than 200 separate palaeosols are described from three sections through the formation. The palaeosols range in thickness from 0.02 to 1.85 m and are diverse: most are Entisols and Inceptisols (63%), indicating relatively brief periods of soil development. Gleyed Inseptisols and Vertisols are less common (37%). Vertisols are the thickest palaeosols (up to 185 cm) in the Ballagan Formation and have common vertic cracks. Roots are abundant through all the palaeosols, from shallow mats and thin hair-like traces to sporadic thicker root traces typical of arborescent lycopods.
Geochemical, isotope and clay mineralogical analyses of the palaeosols indicate a range in soil alkalinity and amount of water logging. Estimates of mean annual rainfall from palaeosol compositions are 1000 –1500 mm per year. The high mean annual rainfall and variable soil alkalinities contrast markedly with dry periods that developed deep penetrating cracks and evaporite deposits. It is concluded that during the early Carboniferous, this region experienced a sharply contrasting seasonal climate and that the floodplain hosted a mosaic of closely juxtaposed but distinct habitats in which the tetrapods lived. The diversification of coastal floodplain environments identified here may link to the evolution and movement of tetrapods into the terrestrial realm
New Australian guidelines for the treatment of alcohol problems: an overview of recommendations
Summary of recommendations and levels of evidence
Chapter 2: Screening and assessment for unhealthy alcohol use
Screening
Screening for unhealthy alcohol use and appropriate interventions should be implemented in general practice (Level A), hospitals (Level B), emergency departments and community health and welfare settings (Level C).
Quantity–frequency measures can detect consumption that exceeds levels in the current Australian guidelines (Level B).
The Alcohol Use Disorders Identification Test (AUDIT) is the most effective screening tool and is recommended for use in primary care and hospital settings. For screening in the general community, the AUDIT-C is a suitable alternative (Level A).
Indirect biological markers should be used as an adjunct to screening (Level A), and direct measures of alcohol in breath and/or blood can be useful markers of recent use (Level B).
Assessment
Assessment should include evaluation of alcohol use and its effects, physical examination, clinical investigations and collateral history taking (Level C).
Assessment for alcohol-related physical problems, mental health problems and social support should be undertaken routinely (GPP).
Where there are concerns regarding the safety of the patient or others, specialist consultation is recommended (Level C).
Assessment should lead to a clear, mutually acceptable treatment plan which specifies interventions to meet the patient’s needs (Level D).
Sustained abstinence is the optimal outcome for most patients with alcohol dependence (Level C).
Chapter 3: Caring for and managing patients with alcohol problems: interventions, treatments, relapse prevention, aftercare, and long term follow-up
Brief interventions
Brief motivational interviewing interventions are more effective than no treatment for people who consume alcohol at risky levels (Level A).
Their effectiveness compared with standard care or alternative psychosocial interventions varies by treatment setting. They are most effective in primary care settings (Level A).
Psychosocial interventions
Cognitive behaviour therapy should be a first-line psychosocial intervention for alcohol dependence. Its clinical benefit is enhanced when it is combined with pharmacotherapy for alcohol dependence or an additional psychosocial intervention (eg, motivational interviewing) (Level A).
Motivational interviewing is effective in the short term and in patients with less severe alcohol dependence (Level A).
Residential rehabilitation may be of benefit to patients who have moderate-to-severe alcohol dependence and require a structured residential treatment setting (Level D).
Alcohol withdrawal management
Most cases of withdrawal can be managed in an ambulatory setting with appropriate support (Level B).
Tapering diazepam regimens (Level A) with daily staged supply from a pharmacy or clinic are recommended (GPP).
Pharmacotherapies for alcohol dependence
Acamprosate is recommended to help maintain abstinence from alcohol (Level A).
Naltrexone is recommended for prevention of relapse to heavy drinking (Level A).
Disulfiram is only recommended in close supervision settings where patients are motivated for abstinence (Level A).
Some evidence for off-label therapies baclofen and topiramate exists, but their side effect profiles are complex and neither should be a first-line medication (Level B).
Peer support programs
Peer-led support programs such as Alcoholics Anonymous and SMART Recovery are effective at maintaining abstinence or reductions in drinking (Level A).
Relapse prevention, aftercare and long-term follow-up
Return to problematic drinking is common and aftercare should focus on addressing factors that contribute to relapse (GPP).
A harm-minimisation approach should be considered for patients who are unable to reduce their drinking (GPP).
Chapter 4: Providing appropriate treatment and care to people with alcohol problems: a summary for key specific populations
Gender-specific issues
Screen women and men for domestic abuse (Level C).
Consider child protection assessments for caregivers with alcohol use disorder (GPP).
Explore contraceptive options with women of reproductive age who regularly consume alcohol (Level B).
Pregnant and breastfeeding women
Advise pregnant and breastfeeding women that there is no safe level of alcohol consumption (Level B).
Pregnant women who are alcohol dependent should be admitted to hospital for treatment in an appropriate maternity unit that has an addiction specialist (GPP).
Young people
Perform a comprehensive HEEADSSS assessment for young people with alcohol problems (Level B).
Treatment should focus on tangible benefits of reducing drinking through psychotherapy and engagement of family and peer networks (Level B).
Aboriginal and Torres Strait Islander peoples
Collaborate with Aboriginal or Torres Strait Islander health workers, organisations and communities, and seek guidance on patient engagement approaches (GPP).
Use validated screening tools and consider integrated mainstream and Aboriginal or Torres Strait Islander-specific approaches to care (Level B).
Culturally and linguistically diverse groups
Use an appropriate method, such as the “teach-back” technique, to assess the need for language and health literacy support (Level C).
Engage with culture-specific agencies as this can improve treatment access and success (Level C).
Sexually diverse and gender diverse populations
Be mindful that sexually diverse and gender diverse populations experience lower levels of satisfaction, connection and treatment completion (Level C).
Seek to incorporate LGBTQ-specific treatment and agencies (Level C).
Older people
All new patients aged over 50 years should be screened for harmful alcohol use (Level D).
Consider alcohol as a possible cause for older patients presenting with unexplained physical or psychological symptoms (Level D).
Consider shorter acting benzodiazepines for withdrawal management (Level D).
Cognitive impairment
Cognitive impairment may impair engagement with treatment (Level A).
Perform cognitive screening for patients who have alcohol problems and refer them for neuropsychological assessment if significant impairment is suspected (Level A).
Summary of key recommendations and levels of evidence
Chapter 5: Understanding and managing comorbidities for people with alcohol problems: polydrug use and dependence, co-occurring mental disorders, and physical comorbidities
Polydrug use and dependence
Active alcohol use disorder, including dependence, significantly increases the risk of overdose associated with the administration of opioid drugs. Specialist advice is recommended before treatment of people dependent on both alcohol and opioid drugs (GPP).
Older patients requiring management of alcohol withdrawal should have their use of pharmaceutical medications reviewed, given the prevalence of polypharmacy in this age group (GPP).
Smoking cessation can be undertaken in patients with alcohol dependence and/or polydrug use problems; some evidence suggests varenicline may help support reduction of both tobacco and alcohol consumption (Level C).
Co-occurring mental disorders
More intensive interventions are needed for people with comorbid conditions, as this population tends to have more severe problems and carries a worse prognosis than those with single pathology (GPP).
The Kessler Psychological Distress Scale (K10 or K6) is recommended for screening for comorbid mental disorders in people presenting for alcohol use disorders (Level A).
People with alcohol use disorder and comorbid mental disorders should be offered treatment for both disorders; care should be taken to coordinate intervention (Level C).
Physical comorbidities
Patients should be advised that alcohol use has no beneficial health effects. There is no clear risk-free threshold for alcohol intake. The safe dose for alcohol intake is dependent on many factors such as underlying liver disease, comorbidities, age and sex (Level A).
In patients with alcohol use disorder, early recognition of the risk for liver cirrhosis is critical. Patients with cirrhosis should abstain from alcohol and should be offered referral to a hepatologist for liver disease management and to an addiction physician for management of alcohol use disorder (Level A).
Alcohol abstinence reduces the risk of cancer and improves outcomes after a diagnosis of cancer (Level A)
The terrestrial landscapes of tetrapod evolution in earliest Carboniferous seasonal wetlands of SE Scotland
<scp>ReSurveyEurope</scp>: A database of resurveyed vegetation plots in Europe
AbstractAimsWe introduce ReSurveyEurope — a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We describe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, including potential research questions.ResultsReSurveyEurope includes resurveyed vegetation plots from all habitats. Version 1.0 of ReSurveyEurope contains 283,135 observations (i.e., individual surveys of each plot) from 79,190 plots sampled in 449 independent resurvey projects. Of these, 62,139 (78%) are permanent plots, that is, marked in situ, or located with GPS, which allow for high spatial accuracy in resurvey. The remaining 17,051 (22%) plots are from studies in which plots from the initial survey could not be exactly relocated. Four data sets, which together account for 28,470 (36%) plots, provide only presence/absence information on plant species, while the remaining 50,720 (64%) plots contain abundance information (e.g., percentage cover or cover–abundance classes such as variants of the Braun‐Blanquet scale). The oldest plots were sampled in 1911 in the Swiss Alps, while most plots were sampled between 1950 and 2020.ConclusionsReSurveyEurope is a new resource to address a wide range of research questions on fine‐scale changes in European vegetation. The initiative is devoted to an inclusive and transparent governance and data usage approach, based on slightly adapted rules of the well‐established European Vegetation Archive (EVA). ReSurveyEurope data are ready for use, and proposals for analyses of the data set can be submitted at any time to the coordinators. Still, further data contributions are highly welcome.</jats:sec
Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.
BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden
Drip Irrigation For Agriculture: Untold Stories of Efficiency, Innovation And Development
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