498 research outputs found

    Developments in adaptation to salinity at the crop level

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    The domestication of halophytic species and their use in agriculture has been tested by several authors to replace or supplement the vegetation of saline rangelands. In adopting plants that were originally gathered in nature for controlled cultivation under farmers’ care, the selection favored plant species that were fast-growing, performed well in the absence of other competition and disturbed soil, did not have extensive defense traits, such as thorns or toxins, and produced many seeds. Most of the saline agriculture crops have only recently been entered into breeding and selection programs, although several studies have been done on what people can consider landraces, many of the traits associated with elite varieties have not been systematically studied yet

    Salt-Tolerant Forages for Irrigated Saline Land in Central Iraq

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    Salinity is a major problem in the irrigated zones of central and southern Iraq. We investigated biomass production from five salt-tolerant forage species, represented by 15 introduced accessions and 3 local accessions, during two successive summer growing seasons. Species included pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolour), guar (Cluster bean; Cyamopsis tetragonoloba), cowpea (Vigna unguiculata) and sesbania (Sesbania aculeata and S. sesban). The research site was located in the Al-Dujaila irrigation project area in Wasit. The soil had a silty clay texture with moderate salinity (ECe 10-20 dS/m). The site was irrigated with water (ECw 1.1 dS/m) from the Tigris River on a 3 to 8 day basis. We hypothesised that there would be variation in biomass production, salt accumulation and crude protein both between and within species. In addition, we thought that the legumes would be less productive than grasses as they tend to be more sensitive to salinity. Over 2 experimental seasons, the plants produced an average shoot dry mass of 12.1 t/ha with a range for accessions of 3 to 35 t/ha. There was significant variation both within and between species, supporting the first hypothesis. None of the plants accumulated excessive salt (ash \u3c 12% DM); crude protein was variable (6 to 12%), but higher in two legumes – cowpea and sesbania. Furthermore, there was no evidence that grasses were more productive than legumes, with sesbania and cowpea achieving the highest mean biomass production across the years. We conclude that moderately saline irrigated areas of Iraq can sustain high levels of biomass production for livestock although protein may be limited

    Profitable and Sustainable Grazing Systems for Livestock Producers with Saline Land in Southern Australia

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    Dryland salinity affects over 2.5 M ha in Australia, mostly in southern states and is expanding at 3-5% per year (NLWRA, 2001). The prognosis is for considerable expansion of the area affected by salinity and waterlogging (1217 M ha at equilibrium), because groundwater levels continue to rise and only small-scale land management programmes have been implemented. In addition, many waterways are increasingly saline, especially in the Murray Darling Basin and in Western Australia (WA). Sustainable Grazing on Saline Land (SGSL) addresses the need to make productive use of saline land and water resources. Its research component operates at 12 sites across WA, South Australia (SA), Victoria and New South Wales (NSW) and consists of coordinated activities that have regional relevance and contribute nationally. The programme seeks to develop and demonstrate profitable and sustainable grazing systems on saline land that have positive environmental and social impacts. Whilst there are different priority research issues at each site, data collection is governed by common measurement protocols for salt and water movement, biodiversity, and pasture and animal performance in order to make comparisons and data sharing across sites practical

    Profitable and Sustainable Grazing Systems for Livestock Producers with Saline Land in Southern Australia

    Get PDF
    Dryland salinity affects over 2.5 M ha in Australia, mostly in southern states and is expanding at 3-5% per year (NLWRA, 2001). The prognosis is for considerable expansion of the area affected by salinity and waterlogging (12–17 M ha at equilibrium), because groundwater levels continue to rise and only small-scale land management programmes have been implemented. In addition, many waterways are increasingly saline, especially in the Murray Darling Basin and in Western Australia (WA). Sustainable Grazing on Saline Land (SGSL) addresses the need to make productive use of saline land and water resources. Its research component operates at 12 sites across WA, South Australia (SA), Victoria and New South Wales (NSW) and consists of coordinated activities that have regional relevance and contribute nationally. The programme seeks to develop and demonstrate profitable and sustainable grazing systems on saline land that have positive environmental and social impacts. Whilst there are different priority research issues at each site, data collection is governed by common measurement protocols for salt and water movement, biodiversity, and pasture and animal performance in order to make comparisons and data sharing across sites practical

    Metabolic syndrome components and their response to lifestyle and metformin interventions are associated with differences in diabetes risk in persons with impaired glucose tolerance

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    AIMS: To determine the association of metabolic syndrome (MetS) and its components with diabetes risk in participants with impaired glucose tolerance (IGT), and whether intervention-related changes in MetS lead to differences in diabetes incidence. METHODS: We used the National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATP III) revised MetS definition at baseline and intervention-related changes of its components to predict incident diabetes using Cox models in 3234 Diabetes Prevention Program (DPP) participants with IGT over an average follow-up of 3.2 years. RESULTS: In an intention-to-treat analysis, the demographic-adjusted hazard ratios (95% confidence interval) for diabetes in those with MetS (vs. no MetS) at baseline were 1.7 (1.3-2.3), 1.7 (1.2-2.3) and 2.0 (1.3-3.0) for placebo, metformin and lifestyle groups, respectively. Higher levels of fasting plasma glucose and triglycerides at baseline were independently associated with increased risk of diabetes. Greater waist circumference (WC) was associated with higher risk in placebo and lifestyle groups, but not in the metformin group. In a multivariate model, favourable changes in WC (placebo and lifestyle) and high-density lipoprotein cholesterol (placebo and metformin) contributed to reduced diabetes risk. CONCLUSIONS: MetS and some of its components are associated with increased diabetes incidence in persons with IGT in a manner that differed according to DPP intervention. After hyperglycaemia, the most predictive factors for diabetes were baseline hypertriglyceridaemia and both baseline and lifestyle-associated changes in WC. Targeting these cardiometabolic risk factors may help to assess the benefits of interventions that reduce diabetes incidence

    Subsoil contraints and their management: Overview from five years of R&D

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    Subsoil constraints cost the grains industry more than $1.6b in lost production each year. Diagnosing and mapping subsoil constraints (SSC) was achieved at a shire scale using the DPIRD soils database and historic surveys

    Aβ Vaccination in Combination with Behavioral Enrichment in Aged Beagles: Effects on Cognition, Aβ, and Microhemorrhages

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    Beta-amyloid (Aβ) immunotherapy is a promising intervention to slow Alzheimer’s disease (AD). Aging dogs naturally accumulate Aβ and show cognitive decline. An active vaccine against fibrillar Aβ 1–42 (VAC) in aged beagles resulted in maintenance but not improvement of cognition along with reduced brain Aβ. Behavioral enrichment (ENR) led to cognitive benefits but no reduction in Aβ. We hypothesized cognitive outcomes could be improved by combining VAC with ENR in aged dogs. Aged dogs (11–12 years) were placed into 4 groups: (1) control/control (C/C); (2) control/VAC (C/V); (3) ENR/control (E/C); (4) ENR and VAC (E/V) and treated for 20 months. VAC decreased brain Aβ, pyroglutamate Aβ, increased CSF Aβ42 and BDNF RNA levels but also increased microhemorrhages. ENR reduced brain Aβ and prevented microhemorrhages. The combination treatment resulted in a significant maintenance of learning over time, reduced Aβ and increased BDNF mRNA despite increased microhemorrhages, however there were no benefits to memory. These results suggest that the combination of immunotherapy with behavioral enrichment leads to cognitive maintenance associated with reduced neuropathology that may benefit people with AD

    Full Agreement and the Provision of Threshold Public Goods

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    The experimental evidence suggests that groups are inefficient at providing threshold public goods. This inefficiency appears to reflect an inability to coordinate over how to distribute the cost of providing the good. So, why do groups not just split the cost equally? We offer an answer to this question by demonstrating that in a standard threshold public good game there is no collectively rational recommendation. We also demonstrate that if full agreement is required in order to provide the public good then there is a collectively rational recommendation, namely, to split the cost equally. Requiring full agreement may, therefore, increase efficiency in providing threshold public goods. We test this hypothesis experimentally and find support for it

    Radio Astronomy

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    Contains table of contents for Section 4 and reports on twelve research projects.National Science Foundation Grant AST 88-19848Jet Propulsion Laboratory Contract 957687National Aeronautics and Space Administration Grant NAGW 1386National Science Foundation Grant AST 88-19848Annie Jump Cannon AwardSM Systems and Research, Inc.U.S. Navy Office of Naval Research Contract N00014-88-K-2016NASA/Goddard Space Flight Center Grant NAG 5-537NASA/Goddard Space Flight Center Grant NAG 5-10Woods Hole Oceanographic Institution Contract SC-28860Leaders for Manufacturing Progra
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