2,763 research outputs found
Integrated Scenarios of Regional Development in Two Semi-Arid States of North-Eastern Brazil
Scenario analysis of the future is an important tool for supporting sustainability-oriented regional planning. To assist regional planning in two federal states in semi-arid North-eastern Brazil, CearĂĄ and PiauĂ, we developed integrated qualitativeÂżquantitative scenarios that show potential developments of the agricultural and water resources situation as well as the internal migration until the year 2025. In these states, regional development is negatively influenced by the high seasonality of rainfall and El-NiĂąo-related drought years. Two reference scenarios, 'Coastal Boom and Cash Crops' and 'Decentralisation - Integrated Rural Development' were developed. First, story lines were created and the development of the driving forces was quantified. Then, an integrated model, which includes modules for simulating water availability, water demand, and agricultural production and income, was applied to compute the temporal development of relevant system indicators in each of the 332 municipalities of CearĂĄ and PiauĂ. These indicators encompass the fraction of the irrigation water demand than can be satisfied, the volume of water which is stored in the reservoirs at the beginning of the dry season, agricultural productivity and production as well as the internal migration among scenario regions. In addition, the impact of certain policy measures was assessed in the context of both reference scenarios. Reference and intervention scenarios were derived by an interdisciplinary group of scientists and were discussed and refined during policy workshops with planning agencies of CearĂĄ
Scheduling and Allocation of Non-Manifest Loops on Hardware Graph-Models
We address the problem of scheduling non-manifest data dependant periodic loops for high throughput DSP-applications based on a streaming data model. In contrast to manifest loops, non-manifest data dependant loops are loops where the number of iterations needed in order to perform a calculation is data dependant and hence not known at compile time. For the case of manifest loops, static scheduling techniques have been devised which produce near optimal schedules. Due to the lack of exact run-time execution knowledge of non-manifest loops, these static scheduling techniques are not suitable for tackling scheduling problems of DSP-algorithms with non-manifest loops embedded in them. We consider the case where (a) a-priori knowledge of the data distribution, and (b) worst case execution time of the non-manifest loop are known and a constraint on the total execution time has been given. Under these conditions dynamic schedules of the non-manifest data dependant loops within the DSP-algorithm are possible. We show how to construct hardware which dynamically schedules these non-manifest loops. The sliding window execution, which is the execution of a non-manifest loop when the data streams through it, of the constructed hardware will guarantee real time performance for the worst case situation. This is the situation when each non-manifest loop requires its maximum number of iterations
Language arts enrichment activities for gifted students in grade five
Renewed interest, growing research and implications of state and federal legislation has prompted school districts to initiate programs to provide for the educational needs of the gifted and talented students
Importance of fossil fuel emission uncertainties over Europe for CO2 modeling: model intercomparison
Inverse modeling techniques used to quantify surface carbon fluxes commonly assume that the uncertainty of fossil fuel CO2 (FFCO2) emissions is negligible and that intra-annual variations can be neglected. To investigate these assumptions, we analyzed the differences between four fossil fuel emission inventories with spatial and temporal differences over Europe and their impact on the model simulated CO2 concentration. Large temporal flux variations characterize the hourly fields (~40 % and ~80 % for the seasonal and diurnal cycles, peak-to-peak) and annual country totals differ by 10 % on average and up to 40 % for some countries (i.e., the Netherlands). These emissions have been prescribed to seven different transport models, resulting in 28 different FFCO2 concentrations fields. The modeled FFCO2 concentration time series at surface sites using time-varying emissions show larger seasonal cycles (+2 ppm at the Hungarian tall tower (HUN)) and smaller diurnal cycles in summer (-1 ppm at HUN) than when using constant emissions. The concentration range spanned by all simulations varies between stations, and is generally larger in winter (up to ~10 ppm peak-to-peak at HUN) than in summer (~5 ppm). The contribution of transport model differences to the simulated concentration std-dev is 2â3 times larger than the contribution of emission differences only, at typical European sites used in global inversions. These contributions to the hourly (monthly) std-dev's amount to ~1.2 (0.8) ppm and ~0.4 (0.3) ppm for transport and emissions, respectively. First comparisons of the modeled concentrations with 14C-based fossil fuel CO2 observations show that the large transport differences still hamper a quantitative evaluation/validation of the emission inventories. Changes in the estimated monthly biosphere flux (Fbio) over Europe, using two inverse modeling approaches, are relatively small (less that 5 %) while changes in annual Fbio (up to ~0.15 % GtC yr-1) are only slightly smaller than the differences in annual emission totals and around 30 % of the mean European ecosystem carbon sink. These results point to an urgent need to improve not only the transport models but also the assumed spatial and temporal distribution of fossil fuel emission inventories
Corrigendum to âEvaluation of black carbon estimations in global aerosol modelsâ published in Atmos. Chem. Phys., 9, 9001-9026, 2009
Potential of using remote sensing techniques for global assessment of water footprint of crops
Remote sensing has long been a useful tool in global applications, since it provides physically-based, worldwide, and consistent spatial information. This paper discusses the potential of using these techniques in the research field of water management, particularly for âWater Footprintâ (WF) studies. The WF of a crop is defined as the volume of water consumed for its production, where green and blue WF stand for rain and irrigation water usage, respectively. In this paper evapotranspiration, precipitation, water storage, runoff and land use are identified as key variables to potentially be estimated by remote sensing and used for WF assessment. A mass water balance is proposed to calculate the volume of irrigation applied, and green and blue WF are obtained from the green and blue evapotranspiration components. The source of remote sensing data is described and a simplified example is included, which uses evapotranspiration estimates from the geostationary satellite Meteosat 9 and precipitation estimates obtained with the Climatic Prediction Center Morphing Technique (CMORPH). The combination of data in this approach brings several limitations with respect to discrepancies in spatial and temporal resolution and data availability, which are discussed in detail. This work provides new tools for global WF assessment and represents an innovative approach to global irrigation mapping, enabling the estimation of green and blue water use
Case 213: Primary Spenic Angiosarcoma
A 75-year-old woman with a medical history of gastroesophageal reflux disease and type II diabetes presented to the hospital with a 3-month history of gradually worsening headaches, vague upper abdominal pain, and lower back pain. The patient denied fevers, night sweats, contact with sick individuals, occupational exposure to infection, bleeding, immunodeficiency, intravenous drug use, alcohol or tobacco abuse, history of malignancy, family history of genetic disorders, and international travel. Physical examination revealed a skin-colored mass protruding from the right side of her forehead, but there were no other notable abnormalities. Her diabetes was managed with diet, and the only prescription medication she was taking was esomeprazole. She was not taking anticoagulants. Initial laboratory work-up revealed anemia and profound thrombocytopenia (hemoglobin level, 9.4 g/dL; platelet count, 16 Ă 109/L); these were refractory to aggressive treatment, including plasmapheresis, immunosuppression with prednisolone, and numerous transfusions. Contrast materialâenhanced magnetic resonance (MR) imaging of the head was performed at admission to further evaluate the patientâs headache and the mass on the patientâs forehead. Ultrasonography (US) of the abdomen was performed to evaluate the cause of abdominal pain. The discovery of liver lesions at US led us to perform contrast-enhanced computed tomography (CT) of the chest, abdomen, and pelvis. Contrast-enhanced MR imaging of the abdomen was performed to narrow the diagnostic considerations for the lesions identified at CT. Bone marrow biopsy revealed no evidence of infectious or neoplastic processes. Endoscopy and colonoscopy were performed; however, they revealed no abnormalities. Further laboratory work-up included extensive testing for parasites, fungi, bacteria, and viruses, including the human immunodeficiency virus (HIV). All of the results were negative. On the 17th day of admission, the patient became acutely unresponsive, her condition deteriorated rapidly, and she died. Unenhanced head CT was performed at the time of the patientâs acute decompensation
Advances and visions in large-scale hydrological modelling: findings from the 11th Workshop on Large-Scale Hydrological Modelling
Large-scale hydrological modelling has become increasingly wide-spread during the last decade. An annual workshop series on large-scale hydrological modelling has provided, since 1997, a forum to the German-speaking community for discussing recent developments and achievements in this research area. In this paper we present the findings from the 2007 workshop which focused on advances and visions in large-scale hydrological modelling. We identify the state of the art, difficulties and research perspectives with respect to the themes "sensitivity of model results", "integrated modelling" and "coupling of processes in hydrosphere, atmosphere and biosphere". Some achievements in large-scale hydrological modelling during the last ten years are presented together with a selection of remaining challenges for the future
Sustainability of small reservoirs and large scale water availability under current conditions and climate change
Semi-arid river basins often rely on reservoirs for water supply. Small reservoirs may impact on large-scale water availability both by enhancing availability in a distributed sense and by subtracting water for large downstream user communities, e.g. served by large reservoirs. Both of these impacts of small reservoirs are subject to climate change. Using a case-study on North-East Brazil, this paper shows that climate change impacts on water availability may be severe, and impacts on distributed water availability from small reservoirs may exceed impacts on centralised water availability from large reservoirs. Next, the paper shows that the effect of small reservoirs on water availability from large reservoirs may be significant, and increase both in relative and absolute sense under unfavourable climate change
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