37 research outputs found

    What climate change means for farmers in Africa: A triptych review middle panel: Introductional matters and consequences of global warming for African farmers

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    Climate change seriously influences the livelihoods of African farmers. It was, therefore, felt useful to make an inventory of what climate change really means for them. In this review in three parts, climate change is approached by dealing with the three sides from which the danger comes: (i) global warming, (ii) increasing climate variability, (iii) more (and possibly more severe) meteorological and climatological extreme events. These are the three panels of this triptych review. Vulnerable communities already suffer. They are, therefore, urgently in need of assistance aimedat building resilience, and at undertaking climate change adaptation  efforts to survive and to maintain their livelihoods. Climate change adaptation projects - especially if implemented in the context of adaptation strategies at the macro level - often mobilize public and private stakeholders, engaging them in the problem-solving process. Scientists have an important role to play in these projects. One of the major  problems in guiding rural change, in a rural response to climate change, is the low formal level of education that most farmers have and for which governments have done very little to upgrade it. Improved climate literacy is needed among farmers and a better trained extension that can guide farmers in further rainfall monitoring and rainfall interpretation. Further agro-ecosystem observations that, with the rainfall distribution, explain yields and yield differences are also needed. While it is relatively easy todefine technical messages that can be communicated, one must look beyond “adaptation to current climate variability“. The basic vulnerability factors of communities must be targeted. One of the problems faced is that experts on climate variability and climate change do not really know what information the grassroots need in the short- and medium-term. However, people assisting vulnerable communities do not know what science generated products are available and how to use them. In this first part of the paper, the consequences of global warming are dealt with at length. Increasing temperatures and changing rainfall patterns get attention first. Other consequences of increasing atmospheric  carbondioxide contents and how they influence agricultural production in Africa are also discussed. Ten text boxes distributed over the three parts illustrate local conditions that must be taken into account to understand the impacts/consequences of climate change for African farmers and how they may cope with them.Key words: African farmers, climate change, vulnerabilitie

    Traditional Underground Grain Storage in Clay Soils in Sudan Improved by Recent Innovations

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    In the central clay plain of the Sudan, traditional subsistence farmers and small farmers that also produce for local markets want to keep the region near food self-sufficiency. They combine annual production of sorghum with underground pit storage of part of the harvest. With increasing climate variability this food security is coming more and more under pressure. Farmers recently experimented with pit innovations that would allow storage for more than one season. These innovations were quantified and further improvements were suggested. It was found that in the most abundantly occurring cracking clay soils, wide shallow pits, using thick chaff linings, with wider above ground soil caps, are most suitable for longer term storage

    Effects of external nutrient sources and extreme weather events on the nutrient budget of a Southern European coastal lagoon

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    The seasonal and annual nitrogen (N), phosphorus (P), and carbon (C) budgets of the mesotidal Ria Formosa lagoon, southern Portugal, were estimated to reveal the main inputs and outputs, the seasonal patterns, and how they may influence the ecological functioning of the system. The effects of extreme weather events such as long-lasting strong winds causing upwelling and strong rainfall were assessed. External nutrient inputs were quantified; ocean exchange was assessed in 24-h sampling campaigns, and final calculations were made using a hydrodynamic model of the lagoon. Rain and stream inputs were the main freshwater sources to the lagoon. However, wastewater treatment plant and groundwater discharges dominated nutrient input, together accounting for 98, 96, and 88 % of total C, N, and P input, respectively. Organic matter and nutrients were continuously exported to the ocean. This pattern was reversed following extreme events, such as strong winds in early summer that caused upwelling and after a period of heavy rainfall in late autumn. A principal component analysis (PCA) revealed that ammonium and organic N and C exchange were positively associated with temperature as opposed to pH and nitrate. These variables reflected mostly the benthic lagoon metabolism, whereas particulate P exchange was correlated to Chl a, indicating that this was more related to phytoplankton dynamics. The increase of stochastic events, as expected in climate change scenarios, may have strong effects on the ecological functioning of coastal lagoons, altering the C and nutrient budgets.Portuguese Science and Technology Foundation (FCT) [POCI/MAR/58427/2004, PPCDT/MAR/58427/2004]; Portuguese Science and Technology Foundation (FCT

    Metalloporphyrin intercalation in liposome membranes: ESR study

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    Liposomes characterized by membranes featuring diverse fluidity (liquid-crystalline and/or gel phase), prepared from egg yolk lecithin (EYL) and dipalmitoylphosphatidylcholine (DPPC), were doped with selected metalloporphyrins and the time-related structural and dynamic changes within the lipid double layer were investigated. Porphyrin complexes of Mg(II), Mn(III), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and the metal-free base were embedded into the particular liposome systems and tested for 350 h at 24°C using the electron spin resonance (ESR) spin probe technique. 5-DOXYL, 12-DOXYL, and 16-DOXYL stearic acid methyl ester spin labels were applied to explore the interior of the lipid bilayer. Only the 16-DOXYL spin probe detected evident structural changes inside the lipid system due to porphyrin intercalation. Fluidity of the lipid system and the type of the porphyrin complex introduced significantly affected the intermolecular interactions, which in certain cases may result in self-assembly of metalloporphyrin molecules within the liposome membrane, reflected in the presence of new lines in the relevant ESR spectra. The most pronounced time-related effects were demonstrated by the EYL liposomes (liquid-crystalline phase) when doped with Mg and Co porphyrins, whereas practically no spectral changes were revealed for the metal-free base and both the Ni and Zn dopants. ESR spectra of the porphyrin-doped gel phase of DPPC liposomes did not show any extra lines; however, they indicated the formation of a more rigid lipid medium. Electronic configuration of the porphyrin’s metal center appeared crucial to the degree of molecular reorganization within the phospholipid bilayer system

    Induction of labour versus expectant monitoring in women with pregnancy induced hypertension or mild preeclampsia at term: the HYPITAT trial

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    Contains fulltext : 53183.pdf ( ) (Open Access)BACKGROUND: Hypertensive disorders, i.e. pregnancy induced hypertension and preeclampsia, complicate 10 to 15% of all pregnancies at term and are a major cause of maternal and perinatal morbidity and mortality. The only causal treatment is delivery. In case of preterm pregnancies conservative management is advocated if the risks for mother and child remain acceptable. In contrast, there is no consensus on how to manage mild hypertensive disease in pregnancies at term. Induction of labour might prevent maternal and neonatal complications at the expense of increased instrumental vaginal delivery rates and caesarean section rates. METHODS/DESIGN: Women with a pregnancy complicated by pregnancy induced hypertension or mild preeclampsia at a gestational age between 36+0 and 41+0 weeks will be asked to participate in a multi-centre randomised controlled trial. Women will be randomised to either induction of labour or expectant management for spontaneous delivery. The primary outcome of this study is severe maternal morbidity, which can be complicated by maternal mortality in rare cases. Secondary outcome measures are neonatal mortality and morbidity, caesarean and vaginal instrumental delivery rates, maternal quality of life and costs. Analysis will be by intention to treat. In total, 720 pregnant women have to be randomised to show a reduction in severe maternal complications of hypertensive disease from 12 to 6%. DISCUSSION: This trial will provide evidence as to whether or not induction of labour in women with pregnancy induced hypertension or mild preeclampsia (nearly) at term is an effective treatment to prevent severe maternal complications. TRIAL REGISTRATION: The protocol is registered in the clinical trial register number ISRCTN08132825

    Disproportionate Intrauterine Growth Intervention Trial At Term: DIGITAT

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    Contains fulltext : 65628.pdf ( ) (Open Access)BACKGROUND: Around 80% of intrauterine growth restricted (IUGR) infants are born at term. They have an increase in perinatal mortality and morbidity including behavioral problems, minor developmental delay and spastic cerebral palsy. Management is controversial, in particular the decision whether to induce labour or await spontaneous delivery with strict fetal and maternal surveillance. We propose a randomised trial to compare effectiveness, costs and maternal quality of life for induction of labour versus expectant management in women with a suspected IUGR fetus at term. METHODS/DESIGN: The proposed trial is a multi-centre randomised study in pregnant women who are suspected on clinical grounds of having an IUGR child at a gestational age between 36+0 and 41+0 weeks. After informed consent women will be randomly allocated to either induction of labour or expectant management with maternal and fetal monitoring. Randomisation will be web-based. The primary outcome measure will be a composite neonatal morbidity and mortality. Secondary outcomes will be severe maternal morbidity, maternal quality of life and costs. Moreover, we aim to assess neurodevelopmental and neurobehavioral outcome at two years as assessed by a postal enquiry (Child Behavioral Check List-CBCL and Ages and Stages Questionnaire-ASQ). Analysis will be by intention to treat. Quality of life analysis and a preference study will also be performed in the same study population. Health technology assessment with an economic analysis is part of this so called Digitat trial (Disproportionate Intrauterine Growth Intervention Trial At Term). The study aims to include 325 patients per arm. DISCUSSION: This trial will provide evidence for which strategy is superior in terms of neonatal and maternal morbidity and mortality, costs and maternal quality of life aspects. This will be the first randomised trial for IUGR at term. TRIAL REGISTRATION: Dutch Trial Register and ISRCTN-Register: ISRCTN10363217

    What Climate Change Means For Farmers In Africa: A Triptych Review Right Panel: Climate Extremes And Society’S Responses, Including Mitigation Attempts As Part Of Preparedness Of African Farmers

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    In this paper in three parts, climate change is approached by dealing with the three sides from which the danger comes: (i) global warming, (ii) increasing climate variability, (iii) more (and possibly more severe) meteorological and climatological extreme events. These are the three panels of this triptych review and the right panel on climate extremes and society’s responses, including mitigation attempts as part of preparedness of African farmers, is this part. The occurrence of more (and possibly more severe) extreme meteorological/climatological events, as another likely consequence of climate change, is discussed, reviewing the literature and dealing for Africa with recent droughts and famines. It appears that there is more than sufficient proof that the numbers of disasters have risen globally, and on average at an increasing rate, over the last half a century, with more evidence in the later decades. Extreme hazards have a shorter recurrence time but whether they also have become more severe cannot be easily determined. This is due to developments in observations, populations and vulnerabilities and lack of developments in climate models. Only for increased temperature related disasters, severity has clearly become larger. However, recent more realistic calculations appear to suggest that there has been little change in drought over the past 60 years. In physical terms, there is also little or no evidence of increased severity of floods over the past century. Increasing farmer preparedness will be an important part of better responses to these conditions. The traditional response farming as to droughts, floods (annual recession and recurrent occasional ones), strong winds and other serious disasters should be among starting points. At the end of this paper, the contributions that tropical agriculture can make to reduce greenhouse gases (GHGs) in win-win situations are also dealt with. Soil carbon sequestration has a higher mitigation potential than emission reductions in African agriculture, although both may be important. These are best achieved under management systems with higher carbon density, as well as improved soil conservation. Agroforestry, assisted natural regeneration, forest rehabilitation, forest gardens, and improved forest fallow projects should all be eligible under the Clean Development Mechanism. Throughout the paper text boxes are used that illustrate local conditions that must be taken into account to understand the impacts/consequences of climate change for African farmers and how they may cope with them
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