209 research outputs found

    Assessing Economic Viability of Pasture Enterprise as Adaptation Strategy in Dry Land Ecosystems - A Case of Ijara, Kenya

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    To adapt to impacts of climate change and variability that outwit traditional coping mechanisms, communities in the semi-arid Ijara, spontaneously took to pasture enterprise strategy. The spontaneity translated into unclear costs and benefits that impeded management of the scarce resources. The study clarified costs and benefits by isolating them for analysis and measuring the strategies’ viability for adaptation. The objective was to measure costs incurred and benefits gained from avoided damages through adoption of the strategy at community farm-level. Costs-benefit-analysis was the design used, complemented by the financial market-driven 15% discounting rates and net present values. Also co-ordinated regional downscaling experiment models were used to ascertain climate performance and projection. Household questionnaire was administered to 240 sample size calculated from 9000 farmer population.  Fifty-seven per cent pastoralists had  embraced agro-pastoralism to incorporate on-farm rain-fed Sudan grass, whose input costs were US1333/ha/seasonwithestimatedyieldsof1.8tons/haofdrymatter.CashflowacrossthreerainfedseasonsnettedUS 1333/ha/season with estimated yields of 1.8 tons/ha of dry matter. Cash flow across three rain-fed seasons netted US21390, US45214andUS45214 and US67820 per hectare from one, two and three seasons respectively. Overall net present value was US$ 2000p.a. Equal to 50.5% agro-pastoralists produced fodder that cushioned against the high costs on inter-county importation.  Land size inadequacy and the communal tenure  upset 86.26% producers  whereas 47.5%  were concerned that drought raised production costs the most after that lack of skills 53.08%, feed deficit at 30.41%, and diseases 20.41% in that order. Overall benefits from the strategy exceeded costs, making the investment viable for adaptation. Going forward and considering the limited adaptation capacities, disease control and feed deficit costs, policies need to focus on formulating livestock improvement guidelines to include revitalizing traditional grazing management practices. Other pertinent investment opportunities include strategic value-chain linkages and infrastructure, promotion of rain-fed and irrigated fodder production technologies incorporating climate-smart water harvesting, supporting post-harvest feed reserves technologies, reviewing land tenure system and investing in local farmer-friendly weather data collection and application Keywords: Adaptation strategy, benefits and costs, climate change, pasture enterpris

    Effects of Culture Conditions on Growth of Kefir Grains using Milk for Nutrition and Health: An Application of Response Surface Methodoly with Box-behnken Design.

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    This combined process was successfully modeled by response surface methodology method with a Box–Behnken design. In this work, Box-Behnken Design of response surface methodology was used to investigate the effects of fat content in milk, incubation time and the number of rotations or shaking as culture conditions to for  growing kefir grains using milk as culture liquid. The implementation of first order factorial experiment was based on a 3k Box- Benhnken experimental factorial design with one replicate. Response surface methodology was adopted to express the output parameter (Size of the kefir grain) that is decided by the input parameters (Number of rotations, Time and milk fat content) which yielded the response surface models. The effects of the culture conditions on growth of kefir grains using milk was studied by use of first order model. The adequacy of the first order model was examined by use residual analysis, the normal plot, the main affects plots, the contour plot, and ANOVA statistics F-test, t-test, R2, and the adjusted R. The optimization of culture conditions was achieved by the help of the steepest ascent method to locate the optimal domain and direction of growth of kefir grains. The first order model was predicted using a D-optimal criterion which was used to evaluate the growth of kefir grains. The confidence level to check the growth of kefir grain was at 95%. The data was analyzed using R statistical software and excel. Data was presented using tables and graphs. Milk fat content and number of rotations per minute had a positive effects  while time had a negative effects on the growth of kefir grains using milk. Keywords: Kefir grains; Response Surface Methodology; Box-behnken design; Culture condition

    Unique arbuscular mycorrhizal fungal communities uncovered in date palm plantations and surrounding desert habitats of Southern Arabia

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    The main objective of this study was to shed light on the previously unknown arbuscular mycorrhizal fungal (AMF) communities in Southern Arabia. We explored AMF communities in two date palm (Phoenix dactylifera) plantations and the natural vegetation of their surrounding arid habitats. The plantations were managed traditionally in an oasis and according to conventional guidelines at an experimental station. Based on spore morphotyping, the AMF communities under the date palms appeared to be quite diverse at both plantations and more similar to each other than to the communities under the ruderal plant, Polygala erioptera, growing at the experimental station on the dry strip between the palm trees, and to the communities uncovered under the native vegetation (Zygophyllum hamiense, Salvadora persica, Prosopis cineraria, inter-plant area) of adjacent undisturbed arid habitat. AMF spore abundance and species richness were higher under date palms than under the ruderal and native plants. Sampling in a remote sand dune area under Heliotropium kotschyi yielded only two AMF morphospecies and only after trap culturing. Overall, 25 AMF morphospecies were detected encompassing all study habitats. Eighteen belonged to the genus Glomus including four undescribed species. Glomus sinuosum, a species typically found in undisturbed habitats, was the most frequently occurring morphospecies under the date palms. Using molecular tools, it was also found as a phylogenetic taxon associated with date palm roots. These roots were associated with nine phylogenetic taxa, among them eight from Glomus group A, but the majority could not be assigned to known morphospecies or to environmental sequences in public databases. Some phylogenetic taxa seemed to be site specific. Despite the use of group-specific primers and efficient trapping systems with a bait plant consortium, surprisingly, two of the globally most frequently found species, Glomus intraradices and Glomus mosseae, were not detected neither as phylogenetic taxa in the date palm roots nor as spores under the date palms, the intermediate ruderal plant, or the surrounding natural vegetation. The results highlight the uniqueness of AMF communities inhabiting these diverse habitats exposed to the harsh climatic conditions of Southern Arabia

    NESTOR: A neutrino particle astrophysics underwater laboratory for the Mediterranean

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    Abstract An underwater neutrino astrophysics laboratory, to be located in the international waters off the Southwest of Greece, near the town of Pylos is now under construction. In the last two years a group of physicists from Greece and Russia have carried out two demonstration experiments in 4km deep water, counting muons and verifying the adequacy of the deep sea site. Plans are presented for a 100, 000 m 2 high energy neutrino detector composed of a hexagon of hexagonal towers, with 1176 optical detector units. A progress report is given and the physics potential of a siggle tower with 168 phototubes (currently under construction) is described

    Expansion cone for the 3-inch PMTs of the KM3NeT optical modules

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    [EN] Detection of high-energy neutrinos from distant astrophysical sources will open a new window on the Universe. The detection principle exploits the measurement of Cherenkov light emitted by charged particles resulting from neutrino interactions in the matter containing the telescope. A novel multi-PMT digital optical module (DOM) was developed to contain 31 3-inch photomultiplier tubes (PMTs). In order to maximize the detector sensitivity, each PMT will be surrounded by an expansion cone which collects photons that would otherwise miss the photocathode. Results for various angles of incidence with respect to the PMT surface indicate an increase in collection efficiency by 30% on average for angles up to 45 degrees with respect to the perpendicular. Ray-tracing calculations could reproduce the measurements, allowing to estimate an increase in the overall photocathode sensitivity, integrated over all angles of incidence, by 27% (for a single PMT). Prototype DOMs, being built by the KM3NeT consortium, will be equipped with these expansion cones.This work is supported through the EU, FP6 Contract no. 011937, FP7 grant agreement no. 212252, and the Dutch Ministry of Education, Culture and Science.Adrián Martínez, S.; Ageron, M.; Aguilar, JA.; Aharonian, F.; Aiello, S.; Albert, A.; Alexandri, M.... (2013). Expansion cone for the 3-inch PMTs of the KM3NeT optical modules. Journal of Instrumentation. 8(3):1-19. https://doi.org/10.1088/1748-0221/8/03/T03006S1198

    The Efficiency and Equity of the Tax and Transfer System in France

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    Taxes and cash transfers reduce income inequality more in France than elsewhere in the OECD, because of the large size of the flows involved. But the system is complex overall. Its effectiveness could be enhanced in many ways, for example so as to achieve the same amount of redistribution at lower cost. This Working Paper relates to the 2013 OECD Economic Review of France (www.oecd.org/eco/surveys/France).http://deepblue.lib.umich.edu/bitstream/2027.42/133065/1/wp1047.pd

    Detection potential of the KM3NeT detector for high-energy neutrinos from the Fermi bubbles

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    A recent analysis of the Fermi Large Area Telescope data provided evidence for a high-intensity emission of high-energy gamma rays with a E 2 spectrum from two large areas, spanning 50 above and below the Galactic centre (the ‘‘Fermi bubbles’’). A hadronic mechanism was proposed for this gamma-ray emission making the Fermi bubbles promising source candidates of high-energy neutrino emission. In this work Monte Carlo simulations regarding the detectability of high-energy neutrinos from the Fermi bubbles with the future multi-km3 neutrino telescope KM3NeT in the Mediterranean Sea are presented. Under the hypothesis that the gamma-ray emission is completely due to hadronic processes, the results indicate that neutrinos from the bubbles could be discovered in about one year of operation, for a neutrino spectrum with a cutoff at 100 TeV and a detector with about 6 km3 of instrumented volume. The effect of a possible lower cutoff is also considered.Published7–141.8. Osservazioni di geofisica ambientaleJCR Journalrestricte
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