Science.gov

Sample records for agricultural return flow

  1. Changes in Soil Chemistry and Agricultural Return Flow in an Integrated Seawater Agriculture System (ISAS) Demonstration in Abu Dhabi

    NASA Astrophysics Data System (ADS)

    Ning, Q.; Matiin, W. A.; Ahmad, F.

    2012-12-01

    Growing halophytes using Integrated Seawater Agriculture Systems (ISAS) offers a sustainable solution for the generation of biomass feedstock for carbon neutral biofuels - halophytes do not enter the foodchain and they do not compete with food-crops for natural resources. A field demonstration of ISAS in the coastal regions of Abu Dhabi, UAE, scheduled to start in 2013, will likely face a number of region-specific challenges not encountered in past demonstrations of ISAS at coastal locations in Mexico and Eritrea. The arid climate, unique soil chemistry (evaporite deposits, especially gypsum), and hypersaline coastal hydrogeology of Abu Dhabi will affect long-term halophyte agricultural productivity when Arabian Gulf seawater is applied to coastal soils as part of ISAS. Therefore, the changes in irrigation return flow quality and soil chemistry must be monitored closely over time to establish transient salt and water balances in order to assess the sustainability of ISAS in the region. As an initial phase of the ISAS demonstration project, numerical modeling of different seawater loadings onto coastal soils was conducted to estimate the chemical characteristics of soil and the irrigation return flow over time. These modeling results will be validated with field monitoring data upon completion of one year of ISAS operation. The results from this study could be used to (i) determine the optimal saline water loading that the soils at the ISAS site can tolerate, (ii) potential for sodicity of the soil with saline water application, (iii) impacts of land application of saline water on underlying coastal groundwater, and (iv) develop strategies to control soil water activities in favor of halophyte agricultural productivity.

  2. River water quality management considering agricultural return flows: application of a nonlinear two-stage stochastic fuzzy programming.

    PubMed

    Tavakoli, Ali; Nikoo, Mohammad Reza; Kerachian, Reza; Soltani, Maryam

    2015-04-01

    In this paper, a new fuzzy methodology is developed to optimize water and waste load allocation (WWLA) in rivers under uncertainty. An interactive two-stage stochastic fuzzy programming (ITSFP) method is utilized to handle parameter uncertainties, which are expressed as fuzzy boundary intervals. An iterative linear programming (ILP) is also used for solving the nonlinear optimization model. To accurately consider the impacts of the water and waste load allocation strategies on the river water quality, a calibrated QUAL2Kw model is linked with the WWLA optimization model. The soil, water, atmosphere, and plant (SWAP) simulation model is utilized to determine the quantity and quality of each agricultural return flow. To control pollution loads of agricultural networks, it is assumed that a part of each agricultural return flow can be diverted to an evaporation pond and also another part of it can be stored in a detention pond. In detention ponds, contaminated water is exposed to solar radiation for disinfecting pathogens. Results of applying the proposed methodology to the Dez River system in the southwestern region of Iran illustrate its effectiveness and applicability for water and waste load allocation in rivers. In the planning phase, this methodology can be used for estimating the capacities of return flow diversion system and evaporation and detention ponds. PMID:25740683

  3. Assessment of agricultural return flows under changing climate and crop water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water rights, policy and emergent water markets in the semi-arid regions of the western USA, and worldwide, call for improved estimates of agricultural water budgets. Agricultural water is seen as a major potential water supply with high commodity value as municipalities seek water security under g...

  4. Environmental water incentive policy and return flows

    NASA Astrophysics Data System (ADS)

    Qureshi, M. E.; Schwabe, K.; Connor, J.; Kirby, M.

    2010-04-01

    With increasing urban, industrial, and agricultural water demand and projected reduced supply under climate change, allocations to the environment are critically low in many arid and semiarid basins. Consequently, many governments are striving to augment environmental flows, often through market-oriented mechanisms that involve compensating irrigated agriculture, the largest water user in most basins, for reducing diversions. A widely documented challenge with policies to recover water for the environment arises because part of the water diversion reduction can form the basis for downstream consumptive water rights or environmental flows. This article gives an empirical comparison of two incentive policies to acquire water for environmental flows for a part of the Murray-Darling Basin (MDB), Australia. One policy consists of paying irrigators and water delivery firms to make capital and management investments that improve on-farm irrigation and water-conveyance; the other policy consists of having the government buy water from irrigators on the active MDB water market. The results show that the first option results in relatively larger return flow reduction, while the second option tends to induce significant irrigated land retirement with relatively large reductions in consumptive use and small reductions in return flow. In cases where irrigation losses result in little useful return flow (e.g., evaporative loss reduction or during drought in some instances), efficiency-improving investments may provide some cost-effective opportunities. Where a large portion of loss forms valuable return flow, it is difficult to make a case for the cost-effectiveness of policies involving payments for investments in irrigation and conveyance system upgrades.

  5. Heat Pipe Blocks Return Flow

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1982-01-01

    Metal-foil reed valve in conventional slab-wick heat pipe limits heat flow to one direction only. With sink warmer than source, reed is forced closed and fluid returns to source side through annular transfer wick. When this occurs, wick slab on sink side of valve dries out and heat pipe ceases to conduct heat.

  6. ACHIEVING IRRIGATION RETURN FLOW QUALITY CONTROL THROUGH IMPROVED LEGAL SYSTEMS

    EPA Science Inventory

    The key to irrigated agricultural return flow quality control is proper utilization and management of the resource itself, and an accepted tool in out society is the law. This project is designed to develop legal alternatives that will facilitate the implementation of improved wa...

  7. Occurrence, distribution, and transport of pesticides in agricultural irrigation-return flow from four drainage basins in the Columbia Basin Project, Washington, 2002-04, and comparison with historical data

    USGS Publications Warehouse

    Wagner, Richard J.; Frans, Lonna M.; Huffman, Raegan L.

    2006-01-01

    Water-quality samples were collected from sites in four irrigation return-flow drainage basins in the Columbia Basin Project from July 2002 through October 2004. Ten samples were collected throughout the irrigation season (generally April through October) and two samples were collected during the non-irrigation season. Samples were analyzed for temperature, pH, specific conductance, dissolved oxygen, major ions, trace elements, nutrients, and a suite of 107 pesticides and pesticide metabolites (pesticide transformation products) and to document the occurrence, distribution, and pesticides transport and pesticide metabolites. The four drainage basins vary in size from 19 to 710 square miles. Percentage of agricultural cropland ranges from about 35 percent in Crab Creek drainage basin to a maximum of 75 percent in Lind Coulee drainage basin. More than 95 percent of cropland in Red Rock Coulee, Crab Creek, and Sand Hollow drainage basins is irrigated, whereas only 30 percent of cropland in Lind Coulee is irrigated. Forty-two pesticides and five metabolites were detected in samples from the four irrigation return-flow drainage basins. The most compounds detected were in samples from Sand Hollow with 37, followed by Lind Coulee with 33, Red Rock Coulee with 30, and Crab Creek with 28. Herbicides were the most frequently detected pesticides, followed by insecticides, metabolites, and fungicides. Atrazine, bentazon, diuron, and 2,4-D were the most frequently detected herbicides and chlorpyrifos and azinphos-methyl were the most frequently detected insecticides. A statistical comparison of pesticide concentrations in surface-water samples collected in the mid-1990s at Crab Creek and Sand Hollow with those collected in this study showed a statistically significant increase in concentrations for diuron and a statistically significant decrease for ethoprophos and atrazine in Crab Creek. Statistically significant increases were in concentrations of bromacil, diuron, and

  8. Quantifying Irrigation Return Flows Using Stable Isotopes of Water along the South Platte River, Colorado USA

    NASA Astrophysics Data System (ADS)

    Sanford, W. E.; Davila Olmo, K.; Stednick, J. D.

    2011-12-01

    As the South Platte River flows from Denver, CO to the Nebraska border it crosses urban and agricultural settings which affect water quality and quantity. This reach of the river is highly regulated, with numerous diversions, off-channel reservoirs, and flow-augmentation projects. Water in the river is used 7 different times between Denver and the state line. Much of the water diverted from the river is used for irrigation. A significant portion of this water returns to the river as groundwater flow, often during times of low stream flow. Groundwater return flows, coupled with wastewater treatment plant and reservoir storage, have turned the once ephemeral river into a perennial one. The goal of this research was to determine if the stable isotopes of water (δ 2H and δ18O) in the river can be used to identify and to help quantify groundwater return flows to the river. Water samples were collected and analyzed for their isotopic signature at 17 sites from Denver to Julesburg. Nine rounds of samples were collected from June 2009 to June 2010. Well defined linear patterns of isotope ratios are observed on individual sampling events indicating that the water in the river is becoming enriched as it moves downstream. The enrichment is caused by evaporation from irrigation waters and their discharge to the river as groundwater return flows. These promising results indicate that it may be possible to quantify irrigation return flow to the South Platte River using the stable isotopes of water.

  9. WESTERN WATER LAWS AND IRRIGATION RETURN FLOW

    EPA Science Inventory

    The impact of water law allocation and use of waters within the Western United States is currently recognized as one of the major constraints to adaptation by irrigated agriculture of more efficient operation practices. This project provides a background of the law and evaluation...

  10. Return of the Gentleman Farmer?: Conceptualising Gentrification in UK Agriculture

    ERIC Educational Resources Information Center

    Sutherland, Lee-Ann

    2012-01-01

    In this paper, processes of gentrification are assessed in relation to non-commercial farming: the production of agricultural commodities without the intent of earning a living. The author argues that due to the connection between residence and productive assets (particularly land) inherent in farming, agricultural gentrification represents a…

  11. PREDICTION OF MINERAL QUALITY OF IRRIGATION RETURN FLOW. VOLUME V. DETAILED RETURN FLOW SALINITY AND NUTRIENT SIMULATION MODEL

    EPA Science Inventory

    A return flow quality simulation model is described which models the plant-soil-aquifer system from the soil surface to a tile or open drain. Processes simulated include evapotranspiration, unsaturated and saturated water flow, solution-precipitation of slightly soluble salts, io...

  12. Returns to Human and Research Capital, United States Agriculture, 1949-1964.

    ERIC Educational Resources Information Center

    Fishelson, Gideon

    This study estimated rates of return to public investments in human and research capital (formal schooling and extension and vocational agricultural education) in the United States agricultural industry. (Southern states were excluded because of demographic and educational factors that would have biased the variables.) Output per farm was defined…

  13. Role of Suspended Sediment in Irrigation Return Flow Chemistry, Southern Alberta

    NASA Astrophysics Data System (ADS)

    Joseph, Helen C.; Ongley, Edwin D.

    1986-05-01

    Chemical impact of irrigation return flows upon receiving waters has historically focussed on salt and sediment production. Transport of other agricultural pollutants which are preferentially associated with suspended sediment is largely unknown in western Canada and poorly addressed elsewhere because of the traditional emphasis upon whole and filtered water chemistry. This study examines the role of suspended sediment in the flux of phosphorus and metals from large-scale irrigation in semiarid southern Alberta. It establishes temporal patterns of chemical flux over the irrigation season, identifies the chemical species of phosphorus and metals, and assesses the potential for phosphorus and heavy metal impact from irrigation return flows upon receiving riverine systems. Whole and filtered water chemistry is found to be not especially useful in determining either chemical enrichment of return flows nor for evaluating impact upon receiving waters. Suspended sediment plays a major role in transport of phosphorus and heavy metals. Evidence from parent materials, prairie soils, chemical speciation, statistical relationships for metals and for phosphorus, and comparative data for suspended sediment during spring high flow in receiving rivers when sediments originate from eroding diffuse sources, all indicate that sediment-associated phosphorus and metals in irrigation return flows are not anthropogenically enriched and do not represent an impact beyond that which is naturally occurring in receiving rivers.

  14. MINIMIZING SALT IN RETURN FLOW THROUGH IRRIGATION MANAGEMENT

    EPA Science Inventory

    Two field experiments were conducted in southwest Arizona to investigate the potential of reducing the salt load in irrigation return flow by decreased leaching. Three leaching treatments of 5, 10, and 20%, replicated nine times for citrus and five times for alfalfa, were establi...

  15. Agricultural Virtual Water Flows in the USA

    NASA Astrophysics Data System (ADS)

    Konar, M.; Dang, Q.; Lin, X.

    2014-12-01

    Global virtual water trade is an important research topic that has yielded several interesting insights. In this paper, we present a comprehensive assessment of virtual water flows within the USA, a country with global importance as a major agricultural producer and trade power. This is the first study of domestic virtual water flows based upon intra-national food flow data and it provides insight into how the properties of virtual water flows vary across scales. We find that both the value and volume of food flows within the USA are roughly equivalent to half that of international flows. However, USA food flows are more water intensive than international food trade, due to the higher fraction of water-intensive meat trade within the USA. The USA virtual water flow network is more social, homogeneous, and equitable than the global virtual water trade network, although it is still not perfectly equitable. Importantly, a core group of U.S. States is central to the network structure, indicating that both domestic and international trade may be vulnerable to disruptive climate or economic shocks in these U.S. States.

  16. SOCIO-ECONOMIC AND INSTITUTIONAL FACTORS IN IRRIGATION RETURN FLOW QUALITY CONTROL. VOLUME IV. GRAND VALLEY CASE STUDY

    EPA Science Inventory

    The Grand Valley was used as a case study area for developing an effective process for implementing technical and institutional solutions to the problem of pollution from irrigation return flows. This area is the most significant agricultural salt source in the Upper Colorado Riv...

  17. Effects of crop residue returning on nitrous oxide emissions in agricultural soils

    NASA Astrophysics Data System (ADS)

    Shan, Jun; Yan, Xiaoyuan

    2013-06-01

    Crop residue returning is a common practice in agricultural system that consequently influences nitrous oxide (N2O) emissions. Much attention has been focused on the effects of crop residue on N2O release. However, no systematic result has yet been drawn because environmental factors among different studies vary. A meta-analysis was described to integrate 112 scientific assessments of crop residue returning on N2O emissions in this study. Results showed that crop residue returning, when averaged across all studies, had no statistically significant effect on N2O release compared with control treatments. However, the range of effects of crop residue returning on N2O emission was significantly affected by synthetic nitrogen (N) fertilizer application, type of crop residue, specific manner in which crop residue has returned, and type of land-use. N2O release was significantly inhibited by 11.7% and 27.1% (P < 0.05) when crop residue was with synthetic N fertilizer and when type of land-use was paddy, respectively. While N2O emissions were significantly enhanced by 42.1% and 23.5% (P < 0.05) when crop residue was applied alone and when type of land-use was upland, respectively. N2O emissions were likewise increased when crop residue with lower C/N ratio was used, mulching of crop residue was performed, and type of land-use was fallow. Our study provides the first quantitative analysis of crop residue returning on N2O emissions, indicating that crop residue returning has no statistically significant effect on N2O release at regional scale, and underlining that the Intergovernmental Panel on Climate Change guidelines should take the opposite effects of crop residue returning on upland and paddy into account when estimating the N2O emission factor of crop residue for different land-use types. Given that most of data are dominated by certain types of crop residue and specific application methods, more field data are required to reduce uncertainty.

  18. Effect of irrigation return flow on groundwater recharge in an overexploited aquifer in Bangladesh

    NASA Astrophysics Data System (ADS)

    Touhidul Mustafa, Syed Md.; Shamsudduha, Mohammad; Huysmans, Marijke

    2016-04-01

    Irrigated agriculture has an important role in the food production to ensure food security of Bangladesh that is home to over 150 million people. However, overexploitation of groundwater for irrigation, particularly during the dry season, causes groundwater-level decline in areas where abstraction is high and surface geology inhibits direct recharge to underlying shallow aquifer. This is causing a number of potential adverse socio-economic, hydrogeological, and environmental problems in Bangladesh. Alluvial aquifers are primarily recharged during monsoon season from rainfall and surface sources. However, return flow from groundwater-fed irrigation can recharge during the dry months. Quantification of the effect of return flow from irrigation in the groundwater system is currently unclear but thought to be important to ensure sustainable management of the overexploited aquifer. The objective of the study is to investigate the effect of irrigation return flow on groundwater recharge in the north-western part of Bangladesh, also known as Barind Tract. A semi-physically based distributed water balance model (WetSpass-M) is used to simulate spatially distributed monthly groundwater recharge. Results show that, groundwater abstraction for irrigation in the study area has increased steadily over the last 29 years. During the monsoon season, local precipitation is the controlling factor of groundwater recharge; however, there is no trend in groundwater recharge during that period. During the dry season, however, irrigation return-flow plays a major role in recharging the aquifer in the irrigated area compared to local precipitation. Therefore, during the dry season, mean seasonal groundwater recharge has increased and almost doubled over the last 29 years as a result of increased abstraction for irrigation. The increase in groundwater recharge during dry season has however no significant effect in the improvement of groundwater levels. The relation between groundwater

  19. The steady-state flow quality in a model of a non-return wind tunnel

    NASA Technical Reports Server (NTRS)

    Mort, K. W.; Eckert, W. T.; Kelly, M. W.

    1972-01-01

    The structural cost of non-return wind tunnels is significantly less than that of the more conventional closed-circuit wind tunnels. However, because of the effects of external winds, the flow quality of non-return wind tunnels is an area of concern at the low test speeds required for V/STOL testing. The flow quality required at these low speeds is discussed and alternatives to the traditional manner of specifying the flow quality requirements in terms of dynamic pressure and angularity are suggested. The development of a non-return wind tunnel configuration which has good flow quality at low as well as at high test speeds is described.

  20. Water temperature in irrigation return flow from the Upper Snake Rock watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water returning to a river from an irrigated watershed could increase the water temperature in the river. The objective of this study was to compare the temperature of irrigation return flow water with the temperature of the diverted irrigation water. Water temperature was measured weekly in the mai...

  1. Partitioning groundwater recharge between rainfall infiltration and irrigation return flows using stable isotopes: the Crau aquifer.

    NASA Astrophysics Data System (ADS)

    Seraphin, Pierre; Vallet-Coulomb, Christine; Gonçalvès, Julio

    2016-04-01

    Traditional flood irrigation is used since the 16th century in the Crau plain (Southern France) for hay production. To supply this high consuming irrigation practice, water is diverted from the Durance River, originating from the Alps, and the large amount of irrigation return flows constitutes the main recharge of the Crau aquifer, which is in turn largely exploited for domestic, industrial and agricultural water use. A possible reduction of irrigation fluxes due to a need of water saving or to a future land-use change could endanger the groundwater resource. A robust quantification of the groundwater mass balance is thus required to assess a sustainable water management in the region. The high isotopic contrast between these exogenous irrigation waters and local precipitations allows the use of stable isotopes of water as conservative tracers to deduce their contributions to the surface recharge. An extensive groundwater sampling was performed to obtain δ18O and δ2H over the whole aquifer. Based on a new piezometric contour map, combined with a reestimate of the aquifer geometry, the isotopic data are implemented in a geostatistical approach to produce a conceptual equivalent-homogeneous reservoir, in order to apply a simple water and isotope mass balance mixing model. The isotopic composition of the two end-members is assessed, and the quantification of groundwater flows is then used to calculate the two recharge fluxes. Near to steady-state condition, the set of isotopic data treated by geostatistics leads to a recharge by irrigation of 5.20 ± 0.93 m3 s-1 i.e. 1173 ± 210 mm yr-1, and a natural recharge of 2.26 ± 0.91 m3 s-1 i.e. 132 ± 53 mm yr-1. Thus, 70 ± 9% of the effective surface recharge comes from the irrigation return flow, consistent with the literature (between 67% and 78%). This study constitutes a straightforward and independent approach to assess groundwater surface recharges with uncertainties and will help to constrain a future transient

  2. Agricultural phosphorus flow and its environmental impacts in China.

    PubMed

    Chen, M; Chen, J; Sun, F

    2008-11-01

    The transfer of nutrients from agricultural land to waters attracts the attention of policy makers as well as scientists as it plays an increasingly significant role in affecting the water environment. It is therefore essential to first understand the nutrient flow in agricultural systems and then correspondingly formulate a series of cost-effective policies and best management practices (BMPs). On the basis of an emission inventory analysis (EIA) and a nutrient full balance (NFB) calculation, this paper presents a partial substance flow analysis (SFA) method, as well as an Agricultural Phosphorus Flow Analysis (AgiPhosFA) model, to describe the phosphorus (P) flow in the agricultural systems in China and assess the impact of human activities on waters driven by agriculture and rural life. It is estimated that average P input and output were 28.9 kg ha(-1) a(-1) and 14.2 kg ha(-1) a(-1) respectively in China in 2004, while the total P utilization efficiency (Plant uptake P/P input) in agriculture was 45.7% leading to an average P surplus of 14.7 kg ha(-1) a(-1). Excessive P application through mineral fertilizer in the arable farming system has led to the accumulation of soil P and constituted a risk to the recipient water quality, whereas the grassland grazing system is confronted with a severe P deficit problem which has resulted in widespread grass degradation. Therefore it may be an efficient way to mitigate the problems simultaneously by regulating and balancing the P flows between the two systems. Uncertainties of the method and model are also discussed in terms of model conceptualization, data and parameters, and spatial and temporal variability. PMID:18649924

  3. Return Flow in the Gulf of Mexico. Part II: Variability in Return-Flow Thermodynamics Inferred from Trajectories over the Gulf.

    NASA Astrophysics Data System (ADS)

    Lewis, John M.; Crisp, Charlie A.

    1992-08-01

    A return-flow case study is examined with the benefit of an unprecedented set of observations obtained during the Gulf of Mexico Experiment (GUFMEX). This case represents the return of modified continental air to the coastal plain in mid-February, and the work is designed to complement the classificatory study of return flow that is found in the companion paper by Crisp and Lewis.Surface air trajectories are combined with land- and ocean-based upper-air data to methodically follow the airmass modification process from the exit point off the Gulf coastal plain to its subsequent entry point on land. Upper-air data from the U.S. Coast Guard (USCG) ship Salvia are especially valuable in this tracking process, but data from an oil platform at the edge of the continental shelf, as well as special onshore observations, significantly contribute to a macroscopic tracking of air involved in the return flow.Results indicate that the warming and moistening process is complicated and requires careful assessment of both air-sea interaction processes and larger-scale vertical motion. The principal results are 1) the thermodynamic character of the returning air mass exhibits significant differences along the entire Gulf coast, and 2) the mixed-layer modeling theory appears to account for the warming and moistening processes for air in the central Gulf that tracks over the Loop Current. The processes determining the character and stratification of the air mass become very complicated, however, as the air approaches neutrally stable conditions and begins its northward track back toward land.The paper concludes with a synopsis of the airmass modification process built upon a composite chart that combines analyses from the various observational platforms.

  4. Estimating Monthly Water Withdrawals, Return Flow, and Consumptive Use in the Great Lakes Basin

    USGS Publications Warehouse

    Shaffer, Kimberly H.; Stenback, Rosemary S.

    2010-01-01

    Water-resource managers and planners require water-withdrawal, return-flow, and consumptive-use data to understand how anthropogenic (human) water use affects the hydrologic system. Water models like MODFLOW and GSFLOW use calculations and input values (including water-withdrawal and return flow data) to simulate and predict the effects of water use on aquifer and stream conditions. Accurate assessments of consumptive use, interbasin transfer, and areas that are on public supply or sewer are essential in estimating the withdrawal and return-flow data needed for the models. As the applicability of a model to real situations depends on accurate input data, limited or poor water-use data hampers the ability of modelers to simulate and predict hydrologic conditions. Substantial differences exist among the many agencies nationwide that are responsible for compiling water-use data including what data are collected, how the data are organized, how often the data are collected, quality assurance, required level of accuracy, and when data are released to the public. This poster presents water-use information and estimation methods summarized from recent U.S. Geological Survey (USGS) reports with the intent to assist water-resource managers and planners who need estimates of monthly water withdrawals, return flows, and consumptive use. This poster lists references used in Shaffer (2009) for water withdrawals, consumptive use, and return flows. Monthly percent of annual withdrawals and monthly consumptive-use coefficients are used to compute monthly water withdrawals, consumptive use, and return flow for the Great Lakes Basin.

  5. [Response of Soil Respiration and Organic Carbon to Returning of Different Agricultural Straws and Its Mechanism].

    PubMed

    Cao, Zhan-bo; Wang, Lei; Li, Fan; Fu, Xiao-hua; Le, Yi-quan; Wu, Ji-hua; Lu, Bing; Xu, Dian-sheng

    2016-05-15

    Soybean, maize and rice straws were selected as raw materials to study the response of the soil respiration (SR) and soil organic carbon (SOC) to returning of different straws in the Chongming Dongtan area. The results showed that all of SR, SOC and the plant biomass of the lands with returning of different straws were higher than those of the controls. The soil with soybean straw returning possessed the lowest SR and highest SOC among the three kinds of straws, meaning its higher soil organic carbon sequestration capability than corn and maize straws returning. Straw returning significantly enhanced soil dehydrogenase, β-glycosidase activities and microbial biomass, and soil dehydrogenase activity was significantly correlated with soil respiration. The dehydrogenase activity of the soil with soybean straw returning was the lowest, thus, the lowest SR and highest SOC. Soybean straw had the highest cellulose and lignin contents and the lowest N content among the three kinds of straws, resulting in its lowest biodegradability. Therefore, when soybean straw was returned to soil, it was difficult to degrade completely by soil microorganisms, thus the lowest soil microbial activity, eventually leading to the lowest SR and highest SOC. PMID:27506047

  6. Quality of the Arkansas River and irrigation-return flows in the lower Arkansas River Valley, Colorado

    USGS Publications Warehouse

    Cain, Doug

    1985-01-01

    Irrigation-return flows in the lower Arkansas River valley of Colorado were investigated using one-time data at 59 sites, monthly data at 4 sites, and intensive data in a small irrigated area. Specific conductance of return flows increased downstream, paralleling specific conductance of irrigation water. During July 1977, Arkansas River streamflow below Manzanola was mostly irrigation-return flow. A similar situation existed during periods of little precipitation in the early and late irrigation seasons during 1974 to 1978. Irrigation-return flows had a large effect on Arkansas River water quality during these times. (USGS)

  7. Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns for New Instrument Standards

    SciTech Connect

    Walker, Iain; Stratton, Chris

    2015-08-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The study team prepared a draft test method through ASTM International to determine the uncertainty of air flow measurements at residential heating ventilation and air conditioning returns and other terminals. This test method, when finalized, can be used by the Energy Commission and other entities to specify required accuracy of measurement devices used to show compliance with standards.

  8. Climate change and environmental water reallocation in the Murray-Darling Basin: Impacts on flows, diversions and economic returns to irrigation

    NASA Astrophysics Data System (ADS)

    Kirby, J. M.; Connor, J.; Ahmad, M. D.; Gao, L.; Mainuddin, M.

    2014-10-01

    Increasing river environment degradation from historical growth in withdrawal is leading to reallocation of water from irrigation in many basins. We examine how potential reduction in irrigation allocations under a newly enacted environmental water plan for the Murray Darling Basin in Australia, in combination with projected climate change, impact on flows, diversions and the economic returns to irrigation. We use an integrated hydrology-economics model capable of simulating the year-to-year variability of flows, diversions, and economic returns to model three levels of reallocation (2400, 2750 and 3200 GL) under the historical climate, and under a dry, a median and a wet climate change projection. Previous assessments of the reallocation plan do not address climate change impacts, nor the impact of year to year variability in flows on economic returns. The broad results of this analysis are that estimated river flows and diversions are more sensitive to the range of climate change projections than to the range of diversion reallocation scenarios considered. The projected median climate change more or less removes from flows the gains to the environment resulting from reallocation. Reallocations only in combination with no climate change, or climate change at the wetter end of the range of projections, will lead to flows greater than those experienced under the water management regime prior to reallocation. The reduction in economic returns to irrigation is less than the reduction in water available for irrigation: a 25% reduction in the annual average water availability is estimated to reduce the annual average gross value of irrigated agricultural production by about 10%. This is consistent with expectation of economic theory (since more marginal activities are reduced first) and also with observations of reduced water availability and returns in the recent drought in the Murray-Darling Basin. Irrigation returns vary less across the range of climate change

  9. NITROGEN AND IRRIGATION MANAGEMENT TO REDUCE RETURN-FLOW POLLUTION IN THE COLUMBIA BASIN

    EPA Science Inventory

    Cooperative field studies have evaluated dissolved-N levels and leaching, and corresponding crop yields, for potato production practices in the Columbia Basin area of Washington. High dissolved-N levels (with resultant high potential for return-flow pollution) were found througho...

  10. ON-FARM IMPROVEMENTS TO REDUCE SEDIMENT AND NUTRIENTS IN IRRIGATION RETURN FLOW

    EPA Science Inventory

    Research on an 800-hectare irrigated tract in central Washington's Columbia Basin Project studied the effects of on-farm improvements on reduction of the discharge of sediment and nutrients via irrigation return flow. Technical assistance and financial cost-sharing were provided ...

  11. Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns

    SciTech Connect

    Walker, Iain; Stratton, Chris

    2015-07-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent).

  12. Reaping the Return on Agricultural Research and Education in Virginia. Information Series 93-3.

    ERIC Educational Resources Information Center

    Norton, George W.; Paczkowski, Remi

    This report focuses upon the economic and other contributions that agricultural research and education have made to Virginia over the past 40 years. Agricultural research, extension, and classroom instruction contribute in the following ways to Virginia's citizens: increased supplies and reduced costs, improved competitiveness, multiplier effects…

  13. Agricultural virtual water flows within the United States

    NASA Astrophysics Data System (ADS)

    Dang, Qian; Lin, Xiaowen; Konar, Megan

    2015-02-01

    Trade plays an increasingly important role in the global food system, which is projected to be strained by population growth, economic development, and climate change. For this reason, there has been a surge of interest in the water resources embodied in international trade, referred to as "global virtual water trade." In this paper, we present a comprehensive assessment of virtual water flows within the United States (U.S.), a country with global importance as a major agricultural producer and trade power. This is the first study of domestic virtual water flows based upon intranational food transfer empirical data and it provides insight into how the properties of virtual water transfers vary across scales. We find that the volume of virtual water flows within the U.S. is equivalent to 51% of international flows, which is slightly higher than the U.S. food value and mass shares, due to the fact that water-intensive meat commodities comprise a much larger fraction of food transfers within the U.S.. The U.S. virtual water flow network is more social, homogeneous, and equitable than the global virtual water trade network, although it is still not perfectly equitable. Importantly, a core group of U.S. States is central to the network structure, indicating that both domestic and international trade may be vulnerable to disruptive climate or economic shocks in these U.S. States.

  14. Crop diversity effects on productivity and economic returns under dryland agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing crop diversity has been identified as a method to improve agronomic performance of cropping systems and increase provision of ecosystem services. However, there is a need to understand the economic performance of more diverse cropping systems. Crop productivity and economic net returns we...

  15. Return-flow assessment for irrigation command in the Palleru river basin using SWAT model

    NASA Astrophysics Data System (ADS)

    Gosain, A. K.; Rao, Sandhya; Srinivasan, R.; Gopal Reddy, N.

    2005-02-01

    Due to the ever-increasing demand for water resources, the pressure on their judicious utilization is also increasing. Besides being precious, water is also a very complex commodity. The dynamic nature of weather as well as the spatial variability of landmass contribute to the dynamic behaviour of the response of the watersheds to the natural and artificial inputs of water. This requirement has led to the formulation of continuous, distributed parameter, water balance simulation models capable of providing insight into the distribution and utilization of water in a watershed. Since they mimic the natural processes prevalent in the area, they are capable of providing many answers that are normally not easily available otherwise. In the present paper one such situation has been tackled using the SWAT (Soil and Water Assessment Tool) model. The target question was to assess the return flow on account of introducing canal irrigation in a basin (Palleru river basin in the southern state of Andhra Pradesh, India). Since the return flow is dependent on many aspects such as soil characteristics, method of irrigation, etc., it is not appropriate to put a rule-of-thumb value on such quantities. Through modelling, the return flow has been assessed and validated. The temporal variation of such return flows has also been captured. The virgin flows from the basin, before the manmade changes in construction of reservoir and importing water for irrigation were introduced, were also computed as per the requirement of the department. In fact this has been an exercise in demonstrating the usefulness of creating such a base framework capable of helping water managers in planning and management of this very vital resource.

  16. Likelihood of burrow flow in Canadian agricultural lands

    NASA Astrophysics Data System (ADS)

    Dadfar, Humaira; Allaire, Suzanne E.; van Bochove, Eric; Denault, Jean-Thomas; Thériault, Georges; Charles, Anaïs

    2010-05-01

    SummaryIndicators of risk of water contamination (IROWCs) by agricultural contaminants are developed to assess sustainability of agriculture. Burrow flow ( BF) is part of the transport hydrology algorithm used in IROWCs since it is a key pathway for sub-surface contaminant transport. The objectives of this study were to develop a methodology for predicting the likelihood of BF occurrence in agricultural soils across Canada at the landscape scale, and to determine its variation over a 25-year period (1981-2006). The BF algorithm considers the influence of climate, soil properties, and soil management on the likely frequency of BF and distribution of burrows ( B) made by Lumbricus terrestris L. Nova Scotia, Prince Edward Island, Ontario, Quebec, followed by New Brunswick, had the highest likelihood of BF due to favourable humidity, sufficient heat, medium-textured soils, and strong runoff during the growing season and spring thaw. Alberta and Saskatchewan are too dry to favour BF. Areas with high risk of BF fall within locations of high potential for lateral flow due to shallow soils, or to the presence of tile drainage, which may connect BF pathways to important water bodies such as the Great Lakes and the St-Lawrence River. Sensitivity analyses on threshold values used in the BF algorithm indicated that Manitoba is the most sensitive province to changes in precipitation, Quebec to temperature, Prince Edward Island to soil depth, and Ontario to manure application. The BF algorithm can be used as a simple tool to predict the likelihood of water and contaminant transport along earthworm burrows with data available across Canada. It will be upgraded with new data (e.g. climate change) and with an improved algorithm after statistical analyses and correlations with actual water quality data.

  17. Effect of High School Completion of the Agricultural Education Program on the Rate of Return on Investment for the Commonwealth of Virginia

    ERIC Educational Resources Information Center

    Bevins, Phillip Scott

    2010-01-01

    This research study sought to determine the effect high school completion of the agricultural career and technical education program has on the rate of return on investment by public schools in Virginia. The research questions guiding this study included: (1) Were students able to find employment related to the agricultural career and technical…

  18. LOWER PAYETTE RIVER, IDAHO AGRICULTURE IRRIGATION WATER RETURN STUDY AND GROUND WATER EVALUATION, 1992-1993

    EPA Science Inventory

    This report covers the final 17 miles of the Payette River (17050112) and 32,000 acres of irrigated cropland referred to as the Lower Payette State Agricultural Water Quality Project. An in-depth surface and ground water monitoring effort was initiated in June 1992 and completed...

  19. Agricultural policy and social returns to eradication programs: the case of Aujeszky's disease in Sweden.

    PubMed

    Andersson, H; Lexmon, A; Robertsson, J A; Lundeheim, N; Wierup, M

    1997-02-01

    Economic-welfare analysis of animal disease prevention programs frequently ignore the constraints of the agricultural policy environment. Prevention programs affect producers, consumers and the government. The policy environment to a large extent determines the magnitude as well as the distribution of benefits of the program among these groups. The Swedish hog industry has been exposed to three major policy changes during the 1990-1995 period. These scenarios involve various degrees of government intervention in the agricultural sector including internal market deregulation and EU-membership. Aujeszky's disease is a virus disease with swine as the natural infection reservoir. Piglets are the most fragile and an outbreak of the disease results in symptoms such as shaking, cramps and convulsions with an increase in the mortality rate. Slaughter hogs suffer from coughing, fever and reduce their feed consumption. During the last 20-25 years the incidence of Aujeszky's disease (AD) has been increasing in Sweden. In 1989 an eradication program was undertaken. A model is developed to analyze social benefits of an eradication program given variations in agricultural policy. The model refers to the specifics of the AD-program implemented in Sweden. The expected benefits of the program are evaluated using a welfare-economic analysis applying cost-benefit analysis. Total benefits of the program are evaluated across herd and size categories and different regions. Data concerning the frequency of the virus among various categories of herds prior to enacting the program were used (Wahlström et al., 1990). In addition, data from an agricultural insurance company were used to estimate the conditional probability of an outbreak given that the herd is infected. Biological and technical parameter values were collected from a variety of sources. The results of the analysis indicate that the program is economically viable given a social rate of discount in the range of 3-5% without

  20. LABORATORY EVALUATION OF AIR FLOW MEASUREMENT METHODS FOR RESIDENTIAL HVAC RETURNS

    SciTech Connect

    Walker, Iain; Stratton, Chris

    2015-02-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent). Because manufacturers’ accuracy estimates for their equipment do not include many of the sources of error found in actual field measurements (and replicated in the laboratory testing in this study) it is essential for a test method that could be used to determine the actual uncertainty in this specific application. The study team prepared a draft test method through ASTM International to determine the uncertainty of air flow measurements at residential heating ventilation and air conditioning returns and other terminals. This test method, when finalized, can be used by the Energy Commission and other entities to specify required accuracy of measurement devices used to show compliance with standards.

  1. Some Aspects of Forecasting Severe Thunderstorms during Cool-Season Return-Flow Episodes.

    NASA Astrophysics Data System (ADS)

    Weiss, Steven J.

    1992-08-01

    Historically, the Gulf of Mexico has been considered a primary source of water vapor that influences the weather for much of the United States east of the Rocky Mountains. Although severe thunderstorms and tornadoes occur most frequently during the spring and summer months, the periodic transport of Gulf moisture inland ahead of traveling baroclinic waves can result in significant severe-weather episodes during the cool season.To gain insight into the short-range skill in forecasting surface synoptic patterns associated with moisture return from the Gulf, operational numerical weather prediction models from the National Meteorological Center were examined. Sea level pressure fields from the Limited-Area Fine-Mesh Model (LFM), Nested Grid Model (NGM), and the aviation (AVN) run of the Global Spectral Model, valid 48 h after initial data time, were evaluated for three cool-season cases that preceded severe local storm outbreaks. The NGM and AVN provided useful guidance in forecasting the onset of return flow along the Gulf coast. There was a slight tendency for these models to be slightly slow in the development of return flow. In contrast the LFM typically overforecasts the occurrence of return flow and tends to `open the Gulf' from west to east too quickly.Although the low-level synoptic pattern may be forecast correctly, the overall prediction process is hampered by a data void over the Gulf. It is hypothesized that when the return-flow moisture is located over the Gulf, model forecasts of stability and the resultant operational severe local storm forecasts are less skillful compared to situations when the moisture has spread inland already. This hypothesis is tested by examining the performance of the initial second-day (day 2) severe thunderstorm outlook issued by the National Severe Storms Forecast Center during the Gulf of Mexico Experiment (GUFMEX) in early 1988.It has been found that characteristically different air masses were present along the Gulf coast

  2. Development and evaluation of a meter for measuring return line fluid flow rates during drilling

    SciTech Connect

    Loeppke, G.E.; Schafer, D.M.; Glowka, D.A.; Scott, D.D.; Wernig, M.D. ); Wright, E.K. )

    1992-06-01

    The most costly problem routinely encountered in geothermal drilling is lost circulation, which occurs when drilling fluid is lost to the formation rather than circulating back to the surface. The successful and economical treatment of lost circulation requires the accurate measurement of drilling fluid flow rate both into and out of the well. This report documents the development of a meter for measuring drilling fluid outflow rates in the return line of a drilling rig. The meter employs a rolling counterbalanced float that rides on the surface of the fluid in the return line. The angle of the float pivot arm is sensed with a pendulum potentiometer, and the height of the float is calculated from this measurement. The float height is closely related to the fluid height and, therefore, the flow rate in the line. The prototype rolling float meter was extensively tested under laboratory conditions in the Wellbore Hydraulics Flow Facility; results from these tests were used in the design of the field prototype rolling float meter. The field prototype meter was tested under actual drilling conditions in August and September 1991 at the Long Valley Exploratory Well near Mammoth Lakes, Ca. In addition, the performance of several other commercially available inflow and outflow meters was evaluated in the field. The tested inflow meters included conventional pump stroke counters, rotary pump speed counters, magnetic flowmeters, and an ultrasonic Doppler flowmeter. On the return flow line, a standard paddlemeter, an acoustic level meter, and the prototype rolling float meter were evaluated for measuring drilling fluid outflow rates.

  3. Phosphorus transport by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of phosphorus transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. While considerable attention has been devoted to understanding phosphorus losses in overland flow, comparatively limited research has examined ph...

  4. Numerical analysis and simulation of an assured crew return vehicle flow field

    NASA Technical Reports Server (NTRS)

    Weilmuenster, K. James; Smith, Robert E., Jr.; Greene, Francis A.

    1991-01-01

    A lifting body was proposed as a candidate for the Assured Crew Return Vehicle (ACRV) which will serve as a crew rescue vehicle for the Space Station Freedom. The focus is on body surface definition, both surface and volume grid definition, and the computation of inviscid flow fields about the vehicle at wind tunnel conditions. Very good agreement is shown between the computed aerodynamic characteristics of the vehicle at M(sub infinity) = 10 and those measured in wind tunnel tests at high Reynolds numbers.

  5. Control of respiration-driven retrograde flow in the subdiaphragmatic venous return of the Fontan circulation

    PubMed Central

    Vukicevic, M; Conover, T; Jaeggli, M; Zhou, J; Pennati, G; Hsia, TY; Figliola, RS

    2014-01-01

    Respiration influences the subdiaphragmatic venous return in the total cavopulmonary connection (TCPC) of the Fontan circulation whereby both the inferior vena cava (IVC) and hepatic vein flows can experience retrograde motion. Controlling retrograde flows could improve patient outcomes. Using a patient-specific model within a Fontan mock circulatory system with respiration, we inserted a valve into the IVC to examine its effects on local hemodynamics while varying retrograde volumes by changing vascular impedances. A bovine valved conduit reduced IVC retrograde flow to within 3% of antegrade flow in all cases. The valve closed only under conditions supporting retrograde flow and its effects on local hemodynamics increased with larger retrograde volume. Liver and TCPC pressures improved only while the valve leaflets were closed while cycle-averaged pressures improved only slightly (italic>1 mm Hg). Increased pulmonary vascular resistance raised mean circulation pressures but the valve functioned and cardiac output improved and stabilized. Power loss across the TCPC improved by 12–15% (pbold>0.05) with a valve. The effectiveness of valve therapy is dependent on patient vascular impedance. PMID:24814833

  6. Control of respiration-driven retrograde flow in the subdiaphragmatic venous return of the Fontan circulation.

    PubMed

    Vukicevic, Marija; Conover, Timothy; Jaeggli, Michael; Zhou, Jian; Pennati, Giancarlo; Hsia, Tain-Yen; Figliola, Richard S

    2014-01-01

    Respiration influences the subdiaphragmatic venous return in the total cavopulmonary connection (TCPC) of the Fontan circulation whereby both the inferior vena cava (IVC) and hepatic vein flows can experience retrograde motion. Controlling retrograde flows could improve patient outcomes. Using a patient-specific model within a Fontan mock circulatory system with respiration, we inserted a valve into the IVC to examine its effects on local hemodynamics while varying retrograde volumes by changing vascular impedances. A bovine valved conduit reduced IVC retrograde flow to within 3% of antegrade flow in all cases. The valve closed only under conditions supporting retrograde flow and its effects on local hemodynamics increased with larger retrograde volume. Liver and TCPC pressures improved only when the valve leaflets were closed whereas cycle-averaged pressures improved only slightly (<1 mm Hg). Increased pulmonary vascular resistance raised mean circulation pressures, but the valve functioned and cardiac output improved and stabilized. Power loss across the TCPC improved by 12%-15% (p < 0.05) with a valve. The effectiveness of valve therapy is dependent on patient vascular impedance. PMID:24814833

  7. DSMC Dusty Flow Simulation for Non-stop Mars Sample Return Mission

    NASA Astrophysics Data System (ADS)

    Ozawa, T.; Suzuki, T.; Takayanagi, H.; Fujita, K.

    2011-05-01

    At Japan Aerospace Exploration Agency, a non-stop Mars sample return project has been planned. In the project, sampling of Martian dust particles is planned between 35 and 45 km, and the impact of Martian dust particles on a shock structure and aerodynamics for a spacecraft must be clarified. In this work, a mechanism for hypersonic dusty flow simulations in DSMC has been developed, and hypersonic dusty flows were simulated for clear weather and dust storm conditions using two dust-surface interaction models at the descent altitude. It was found that although the impact of dust particles on the shock structure and drag is negligible, the total heat flux is increased with the consideration of dust particles.

  8. Hydraulic flow characteristics of agricultural residues for denitrifying bioreactor media

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrifying bioreactors are a promising technology to mitigate agricultural subsurface drainage nitrate-nitrogen losses, a critical water quality goal for the Upper Mississippi River Basin. This study was conducted to evaluate the hydraulic properties of agricultural residues that are potential bio...

  9. Multiobjective genetic algorithm conjunctive use optimization for production, cost, and energy with dynamic return flow

    NASA Astrophysics Data System (ADS)

    Peralta, Richard C.; Forghani, Ali; Fayad, Hala

    2014-04-01

    Many real water resources optimization problems involve conflicting objectives for which the main goal is to find a set of optimal solutions on, or near to the Pareto front. E-constraint and weighting multiobjective optimization techniques have shortcomings, especially as the number of objectives increases. Multiobjective Genetic Algorithms (MGA) have been previously proposed to overcome these difficulties. Here, an MGA derives a set of optimal solutions for multiobjective multiuser conjunctive use of reservoir, stream, and (un)confined groundwater resources. The proposed methodology is applied to a hydraulically and economically nonlinear system in which all significant flows, including stream-aquifer-reservoir-diversion-return flow interactions, are simulated and optimized simultaneously for multiple periods. Neural networks represent constrained state variables. The addressed objectives that can be optimized simultaneously in the coupled simulation-optimization model are: (1) maximizing water provided from sources, (2) maximizing hydropower production, and (3) minimizing operation costs of transporting water from sources to destinations. Results show the efficiency of multiobjective genetic algorithms for generating Pareto optimal sets for complex nonlinear multiobjective optimization problems.

  10. Environmental flow deficit at global scale - implication on irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Pastor, Amandine; Ludwig, Fulco; Biemans, Hester; Kabat, Pavel

    2016-04-01

    Freshwater species belong to the most degraded ecosystem on earth. At the beginning of the 21st century, scientists have developed the concept of environmental flow requirements (Brisbane declaration 2003) with the aim of protecting freshwater species in the long term. However, the ecological state of rivers is different across the world depending on their fragmentation, on the presence of dams and reservoirs and on the degree of pollution. To implement new regulations on river flow, it is necessary to evaluate the degree of alteration of rivers which we called "environmental flow deficit". The European water framework directive is still working on evaluating the ecological states of river across Europe. In this study, we calculated monthly environmental flow deficit with the global vegetation dynamic and hydrological model LPJml. Environmental flow requirements were first calculated with the Variable Monthly Flow method (Pastor et al., 2014). Then, we checked in each river basin where and when the actual flow (flow minus abstraction for irrigation) does not satisfy environmental flow requirements. We finally show examples of different river basins such as the Nile and the Amazon to show how climate and irrigation can impact river flow and harm freshwater ecosystems.

  11. On the Pathways of the Return Flow of the Meridional Overturning Circulation in the Tropical Atlantic

    NASA Technical Reports Server (NTRS)

    Jochum, Markus

    2002-01-01

    A numerical model of the tropical Atlantic ocean is used to investigate the upper layer pathways of the Meridional Overturning Circulation (MOC) in the tropical Atlantic. The main focus of this thesis is on those parts of the tropical circulation that are thought to be important for the MOC return flow, but whose dynamics have not been understood yet. It is shown how the particular structure of the tropical gyre and the MOO act to inhibit the flow of North Atlantic water into the equatorial thermocline. As a result, the upper layers of the tropical Atlantic are mainly fed by water from the South Atlantic. The processes that carry the South Atlantic water across the tropical Atlantic into the North Atlantic as part of the MOO are described here, and three processes that were hitherto not understood are explained as follows: The North Brazil Current rings are created as the result of the reflection of Rossby waves at the South American coast. These Rossby waves are generated by the barotropically unstable North Equatorial Countercurrent. The deep structure of the rings can be explained by merger of the wave's anticyclones with the deeper intermediate eddies that are generated as the intermediate western boundary current crosses the equator. The bands of strong zonal velocity in intermediate depths along the equator have hitherto been explained as intermediate currents. Here, an alternative interpretation of the observations is offered: The Eulerian mean flow along the equator is negligible and the observations are the signature of strong seasonal Rossby waves. The previous interpretation of the observations can then be explained as aliasing of the tropical wave field. The Tsuchyia Jets are driven by the Eliassen-Palm flux of the tropical instability waves. The equatorial current system with its strong shears is unstable and generates tropical instability waves.

  12. INTEGRATING DESALINATION AND AGRICULTURAL SALINITY CONTROL ALTERNATIVES

    EPA Science Inventory

    The cost-effectiveness relationships for various agricultural and desalination alternatives for controlling salinity in irrigation return flows are developed. Selection of optimal salinity management strategies on a river basin scale is described as a problem of integrating optim...

  13. Fragipan controls on nitrogen loss by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of nutrient transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. We sought to compare nitrogen loss in overland and subsurface flow on two opposing hillslopes (north versus south facing), each with contrasting so...

  14. Field Observations Of The 29 September Tsunami In American Samoa: Spatial Variability And Indications Of Strong Return Flow

    NASA Astrophysics Data System (ADS)

    Jaffe, B. E.; Richmond, B. M.; Gelfenbaum, G. R.; Watt, S.; Apotsos, A. A.; Buckley, M. L.; Dudley, W. C.; Peck, B.

    2009-12-01

    The 29 September 2009 tsunami caused 181 fatalities and displaced more than 5000 people on the islands of Samoa, American Samoa, and Tonga. This is the first tsunami to cause significant damage and fatalities on U.S. soil in more than 30 years. Scientists from around the world quickly mobilized to help document the tsunami water levels before this ephemeral data was forever lost as recovery activities and natural processes overtook the effected area. A USGS team collected data in American Samoa from October 6-22 and November 5-12, 2009. The tsunami was large, reaching elevations of greater than 15 m, however wave heights and devastation varied from village to village in American Samoa. Even within villages, some structures were completely destroyed, some flooded and left standing, and others barely touched. Wave heights, flow depths, runup heights, inundation distances, and flow directions were collected for use in ground-truthing inundation models. The team also collected nearshore bathymetry, topography and reef flat elevation, sediment samples, and documented the distribution and characteristics of both sand and boulder deposits. Eyewitness accounts of the tsunami were also videotaped. One striking aspect of this tsunami was the abundance of indicators of strong return flow. For example at Poloa in the northwest of Tutuila, where the runup was greater than 11 m along a 300-m stretch of coast and flow depths exceeded 4 m, the coral reef flat was strewn with debris including chairs, desks, and books from a school. On land, River channels were excavated and new channels formed as return flow scoured sediment and transported it offshore. Possible causes for the strong return flow and the relation between the stength of the return flow, inundation distance, and runup in American Samoa are presented. These relationships and others based on data collected by field survey teams will ultimately reduce loss of life and destruction from tsunamis in the Pacific and

  15. Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture within the United States is varied and produces a large value ($200 billion in 2002) of production across a wide range of plant and animal production systems. Because of this diversity, changes in climate will likely impact agriculture throughout the United States. Climate affects crop, ...

  16. Puerto Rican Migration: The Return Flow = La Migracion Puertorriquena: El Reflujo a la Isla.

    ERIC Educational Resources Information Center

    Vivo, Paquita, Comp.

    This is a guide to materials and research on Puerto Ricans who have returned to Puerto Rico after living in the United States. Part 1 is an annotated bibliography of books, journal articles, printed documents, doctoral dissertations, master's theses, journalistic accounts, and unpublished papers on characteristics of Puerto Rican return migrants;…

  17. Establishing standards and assessment criteria for ecological instream flow needs in agricultural regions of Canada.

    PubMed

    Peters, Daniel L; Baird, Donald J; Monk, Wendy A; Armanini, David G

    2012-01-01

    Agricultural land use can place heavy demands on regional water resources, strongly influencing the quantity and timing of water flows needed to sustain natural ecosystems. The effects of agricultural practices on streamflow conditions are multifaceted, as they also contribute to the severity of impacts arising from other stressors within the river ecosystem. Thus, river scientists need to determine the quantity of water required to sustain important aquatic ecosystem components and ecological services, to support wise apportionment of water for agricultural use. It is now apparent that arbitrarily defined minimum flows are inadequate for this task because the complex habitat requirements of the biota, which underpin the structure and function of a river ecosystem, are strongly influenced by predictable temporal variations in flow. We present an alternative framework for establishing a first-level, regional ecological instream flow needs standard based on adoption of the Indicators of Hydrologic Alteration/Range of Variability Approach as a broadly applicable hydrological assessment tool, coupling this to the Canadian Ecological Flow Index which assesses ecological responses to hydrological alteration. By explicitly incorporating a new field-based ecological assessment tool for small agricultural streams, we provide a necessary verification of altered hydrology that is broadly applicable within Canada and essential to ensure the continuous feedback between the application of flow management criteria and ecological condition. PMID:22218172

  18. [Contribution of Base Flow to Total Nitrogen Loading in Subtropical Agricultural Catchments].

    PubMed

    Ma, Qiu-mei; Li, Wei; Wang, Yi; Liu, Xin-liang; Li, Yong; Wu, Jin-shui

    2016-04-15

    With the fast development of economics and improvement of people's living standard, non-point source pollution of the agricultural catchments in subtropical China has become more and more severe, where water quality deterioration has become a main barrier for sustainable development and ecological restoration. The process of ecohydrology in catchment is greatly influenced by the process of base flow in channel. This study selected the Tuojia and Jianshan catchments located in Changsha County, Hunan Province, to quantify and compare the contribution of base flow to total nitrogen (TN) loading from January 2011 to December 2013, through field observation and model estimation. The results suggested that the Tuojia catchment with higher intensity of rice agriculture had the greater volume of base flow, higher average flow-weighted TN concentration in base flow, and greater monthly TN loading via base flow [15.2 mm · month⁻¹, 4.14 mg · L⁻¹ and 0.54 kg · (hm² · month)⁻¹, respectively] than those in the Jianshan catchment with lower intensity [11.4 mm · month⁻¹, 1.72 mg · L⁻¹ and 0.20 kg · (hm² · month)⁻¹, respectively]. The base flow contribution to TN loading showed an apparently seasonal pattern. During rice-growing seasons, the contributions of base flow to TN loading were 23.2% and 18.6% in the Tuojia and Jianshan catchments, respectively, lower than those in the fallow seasons (46.9% and 40.0% correspondingly. These results suggested that rice agriculture increased the contribution of base flow in the fallow season to TN loading. Therefore, to alleviate the suffering of non-point source pollution in the rice agriculture catchments, reasonable management measure of rice fields should be implemented to decrease contrihution of base flow to TN loading. PMID:27548958

  19. The future of irrigated agriculture under environmental flow requirements restrictions

    NASA Astrophysics Data System (ADS)

    Pastor, Amandine; Palazzo, Amanda; Havlik, Petr; Kabat, Pavel; Obersteiner, Michael; Ludwig, Fulco

    2016-04-01

    Water is not an infinite resource and demand from irrigation, household and industry is constantly increasing. This study focused on including global water availability including environmental flow requirements with water withdrawal from irrigation and other sectors at a monthly time-step in the GLOBIOM model. This model allows re-adjustment of land-use allocation, crop management, consumption and international trade. The GLOBIOM model induces an endogenous change in water price depending on water supply and demand. In this study, the focus was on how the inclusion of water resources affects land-use and, in particular, how global change will influence repartition of irrigated and rainfed lands at global scale. We used the climate change scenario including a radiative forcing of 8.5 W/m2 (RCP8.5), the socio-economic scenario (SSP2: middle-of-road), and the environmental flow method based on monthly flow allocation (the Variable Monthly Flow method) with high and low restrictions. Irrigation withdrawals were adjusted to a monthly time-step to account for biophysical water limitations at finer time resolution. Our results show that irrigated land might decrease up to 40% on average depending on the choice of EFR restrictions. Several areas were identified as future hot-spots of water stress such as the Mediterranean and Middle-East regions. Other countries were identified to be in safe position in terms of water stress such as North-European countries. Re-allocation of rainfed and irrigated land might be useful information for land-use planners and water managers at an international level to decide on appropriate legislations on climate change mitigation/adaptation when exposure and sensitivity to climate change is high and/or on adaptation measures to face increasing water demand. For example, some countries are likely to adopt measures to increase their water use efficiencies (irrigation system, soil and water conservation practices) to face water shortages, while

  20. Computer program for discounted cash flow/rate of return evaluations

    NASA Technical Reports Server (NTRS)

    Robson, W. D.

    1971-01-01

    Technique, incorporated into set of three computer programs, provides economic methodology for reducing all parameters to financially sound common denominator of present worth, and calculates resultant rate of return on new equipment, processes, or systems investments.

  1. Incorporating a Time Horizon in Rate-of-Return Estimations: Discounted Cash Flow Model in Electric Transmission Rate Cases

    SciTech Connect

    Chatterjee, Bishu; Sharp, Peter A.

    2006-07-15

    Electric transmission and other rate cases use a form of the discounted cash flow model with a single long-term growth rate to estimate rates of return on equity. It cannot incorporate information about the appropriate time horizon for which analysts' estimates of earnings growth have predictive powers. Only a non-constant growth model can explicitly recognize the importance of the time horizon in an ROE calculation. (author)

  2. Financial modeling in medicine: cash flow, basic metrics, the time value of money, discount rates, and internal rate of return.

    PubMed

    Lexa, Frank James; Berlin, Jonathan W

    2005-03-01

    In this article, the authors cover tools for financial modeling. Commonly used time lines and cash flow diagrams are discussed. Commonly used but limited terms such as payback and breakeven are introduced. The important topics of the time value of money and discount rates are introduced to lay the foundation for their use in modeling and in more advanced metrics such as the internal rate of return. Finally, the authors broach the more sophisticated topic of net present value. PMID:17411805

  3. Ensemble Forecasting of Return Flow over the Gulf of Mexico: Value of the Single Upper Air Obseration

    NASA Astrophysics Data System (ADS)

    Lewis, J. M.; Lakshmivarahan, S.; Hu, J.; Weiss, S.

    2014-12-01

    Abstract A case study of return flow over the Gulf of Mexico has been conducted with the intention of determining the value of a single upper-air observation. This case study makes use of a set of upper-air observations collected by the U. S. Coast Guard ship Salvia that followed the trajectory of return-flow air parcels—essentially collecting observations in a Lagrangian frame of reference. A mixed layer model is used to make an ensemble forecast during the outflow phase of the phenomenon—that period when surface-driven buoyancy is the dynamical mechanism that transports moisture and heat into the atmospheric boundary layer. With this low-order nonlinear model, the contributions to forecast uncertainty that stem from initial conditions, boundary conditions, and physical/empirical parameters can be determined separately. These uncertainties serve as input to a three-dimensional variational (3D-Var) data assimilation scheme. Results indicate that the uncertainty in initial conditions dominates the full complement of uncertainties. An experiment is conducted to evaluate the value of a single set of upper-air observations over the Gulf (at a point near the onset of return flow). It is clear from this experiment that observations near the initial onset point significantly improves the forecast of mixing ratio and offers hope for improvement in operational forecasting with a modest increase in resources.

  4. Grassland agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from: shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Degrad...

  5. Nitrogen and salt loads in the irrigation return flows of the Ebro River Basin (Spain)

    NASA Astrophysics Data System (ADS)

    Isidoro, Daniel; Balcells, Maria; Clavería, Ignacio; Dechmi, Farida; Quílez, Dolores; Aragüés, Ramón

    2013-04-01

    The conservation of the quality of surface waters demanded by the European Water Framework Directive requires, among others, an assessment of the irrigation-induced pollution. The contribution of the irrigation return flows (IRF) to the pollution of the receiving water bodies is given by its pollutant load, since this load determines the quality status or pollutant concentration in these water bodies. The aim of this work was to quantify the annual nitrogen and salt loads in the IRF of four irrigated catchments within the Ebro River Basin: Violada (2006-10), Alcanadre (2008-10), Valcuerna (2010), and Clamor Amarga (2010). The daily flow (Q), salt (EC) and nitrate concentration (NO3) were measured in the drainage outlets of each basin. The net irrigation-induced salt and nitrogen loads were obtained from these measurements after discounting the salt and nitrogen inputs from outside the catchments and the non-irrigated areas. The N-fertilizer applications were obtained from farmer surveys and animal farming statistical sources. Irrigation water salinity was very low in all catchments (EC < 0.4 dS/m), but IRF salinity was very high in Valcuerna (7.9 dS/m) with underlain saline lutites, high to moderate in Clamor (2.6 dS/m) and Violada (2.1 dS/m) with gypsum-rich soils, and low in Alcanadre (1.0 dS/m) due to dilution in the inefficient traditional flood-irrigation system. Annual salt loads were highest in Valcuerna (11.9 Mg/ha) and lowest in Alcanadre (3.6 Mg/ha) and Clamor (3.3 Mg/ha). Salt load was also high in flood-irrigated Violada (10.3 Mg/ha), but dropped to 2.6 Mg/ha after its modernization to sprinkler irrigation (in 2008-09). N-fertilizer applications ranged from 221 kg/ha in the corn-dominated Valcuerna in 2010 to 63 kg/ha in 2008 in Violada, when farmers barely applied fertilizers due to the irrigation modernization works in progress that year. The highest N applications derived from pig slurry applications by farmers that used their lands as disposal sites

  6. The Flow of Agricultural Manpower: Its Vocational and Educational Correlates. Final Report.

    ERIC Educational Resources Information Center

    Marvin, R. Paul; Gilbertson, Osmond

    To determine if rural secondary schools were a feasible source of agricultural manpower flow characteristics, 1,302 farmers from 27 southern Minnesota schools were identified on the basis of 1965-1967 school census data. Questionnaires were sent to a random sample of 279, which was divided into those becoming established, those leaving farming,…

  7. Ploidy of USDA (United States Department of Agriculture) world pear germplasm collection determined by flow cytometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Living germplasm collections representing world diversity of pear (Pyrus L.) are maintained by the U.S. Department of Agriculture at the National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon, USA. Flow cytometry was performed on young leaf tissue from 1,284 genebank accessions to assess p...

  8. MODELING LONG-TERM NITRATE BASE-FLOW LOADING FROM TWO AGRICULTURAL WATERSHEDS

    EPA Science Inventory

    Nitrate contamination of ground water from agricultural practices may be contributing to the eutrophication of the Chesapeake Bay, degrading water quality and aquatic habitats. Groundwater flow and nitrate transport and fate are modeled, using MODFLOW and MT3D computer models, in...

  9. Controls of evaporative irrigation return flows in comparison to seawater intrusion in coastal karstic aquifers in northern Sri Lanka: evidence from solutes and stable isotopes

    NASA Astrophysics Data System (ADS)

    Chandrajith, Rohana; Diyabalanage, Saranga; Premathilake, Mahinda; Hanke, Christian; van Geldern, Robert; Barth, Johannes A. C.

    2016-04-01

    region occurs through anthropogenic pollution, and particularly so due to agricultural activities. Extensive groundwater use in the peninsula may also further add concerns of active seawater intrusion after intense abstraction. The area should remain under close monitoring for both quality and quantity in order to protect groundwater as a vulnerable resource. Reference Chandrajith, R., Diyabalanage, S., Premathilake, K.M., Hanke, C., van Geldern, R. and Barth, J.A.C. (2016): Controls of evaporative irrigation return flows in comparison to seawater intrusion in coastal karstic aquifers in northern Sri Lanka: evidence from solutes and stable isotopes. - Science of the Total Environment, in press, [doi:10.1016/j.scitotenv.2016.01.050].

  10. Estimates of Lagrangian particle transport by wave groups: forward transport by Stokes drift and backward transport by the return flow

    NASA Astrophysics Data System (ADS)

    van den Bremer, Ton S.; Taylor, Paul H.

    2014-11-01

    Although the literature has examined Stokes drift, the net Lagrangian transport by particles due to of surface gravity waves, in great detail, the motion of fluid particles transported by surface gravity wave groups has received considerably less attention. In practice nevertheless, the wave field on the open sea often has a group-like structure. The motion of particles is different, as particles at sufficient depth are transported backwards by the Eulerian return current that was first described by Longuet-Higgins & Stewart (1962) and forms an inseparable counterpart of Stokes drift for wave groups ensuring the (irrotational) mass balance holds. We use WKB theory to study the variation of the Lagrangian transport by the return current with depth distinguishing two-dimensional seas, three-dimensional seas, infinite depth and finite depth. We then provide dimensional estimates of the net horizontal Lagrangian transport by the Stokes drift on the one hand and the return flow on the other hand for realistic sea states in all four cases. Finally we propose a simple scaling relationship for the transition depth: the depth above which Lagrangian particles are transported forwards by the Stokes drift and below which such particles are transported backwards by the return current.

  11. The effects of self-generated and applied magnetic fields on the computation of flow over a Mars return aerobrake

    NASA Technical Reports Server (NTRS)

    Palmer, Grant

    1991-01-01

    A CFD technique is developed to calculate the electromagnetic phenomena simultaneously with the fluid flow in the shock layer over an axisymmetric blunt body in a thermal-equilibrium chemical-nonequilibrium environment. The flowfield is solved using an explicit time-marching, first-order spatially accurate scheme. The electromagnetic phenomena are coupled to the real-gas flow solver through an iterative procedure. The electromagnetic terms introduce a strong stiffness, which was overcome by using significantly smaller time steps for the electromagnetic conservation equation. The technique is applied in calculating the flow over a Mars return aerobrake vehicle entering the Earth's atmosphere. For the case where no external field is applied, the electromagnetic effects have little impact on the flowfield.

  12. Sampling strategies for the estimation of salt and nitrate loads in irrigation return flows: La Violada Gully (Spain) as a case study

    NASA Astrophysics Data System (ADS)

    Isidoro, D.; Quílez, D.; Aragüés, R.

    2003-02-01

    Appropriate estimates of salt and nitrate loads exported by irrigated agriculture are needed to ascertain the potential negative impacts on the quality of the receiving water bodies. The irrigation return flows of the La Violada irrigation district (NE Spain), collected by La Violada Gully, were monitored for 4 years (1995-1998) in order to estimate salt and nitrate loads. The existence of a daily cycle in the Gully flow during the April to September 1995 irrigation season, associated with a cycle in the electrical conductivity, made it necessary to analyse the influence of the sampling hour on the daily estimates of salt and nitrate loads. Interpolation and regression methods were evaluated using nine 2-days surveys with samples taken at all even hours. The interpolation approach proved to be reliable for daily load estimations, whereas the regression approach was unacceptable due to the poor salinity-flow and nitrate concentration-flow relationships. The sampling time was important for the determination of salt load by the interpolation method, but resulted almost irrelevant for the estimation of nitrate load. Although the biases represent a small percentage of the mean (<7% for both salt and nitrate load estimates), the lack of consideration of the sampling hour will result, depending on the time of sampling, in a systematic over- or under-estimation of the measured loads. The number of samples needed to estimate salt and nitrate loads within a pre-specified margin of error was determined using the 1995 and 1996 irrigation seasons series and confirmed through a Monte Carlo test for the four irrigation seasons. A systematic sampling interval of 9 days (i.e. 21 samples along the irrigation season) allowed estimating salt loading within a 5% error and nitrating loading within a 10% error at the 95% confidence level.

  13. Preferential flow estimates to an agricultural tile drain with implications for glyphosate transport

    USGS Publications Warehouse

    Stone, W.W.; Wilson, J.T.

    2006-01-01

    Agricultural subsurface drains, commonly referred to as tile drains, are potentially significant pathways for the movement of fertilizers and pesticides to streams and ditches in much of the Midwest. Preferential flow in the unsaturated zone provides a route for water and solutes to bypass the soil matrix and reach tile drains faster than predicted by traditional displacement theory. This paper uses chloride concentrations to estimate preferential flow contributions to a tile drain during two storms in May 2004. Chloride, a conservative anion, was selected as the tracer because of differences in chloride concentrations between the two sources of water to the tile drain, preferential and matrix flow. A strong correlation between specific conductance and chloride concentration provided a mechanism to estimate chloride concentrations in the tile drain throughout the storm hydrographs. A simple mixing analysis was used to identify the preferential flow component of the storm hydrograph. During two storms, preferential flow contributed 11 and 51% of total storm tile drain flow; the peak contributions, 40 and 81%, coincided with the peak tile drain flow. Positive relations between glyphosate [N-(phosphonomethyl)glycine] concentrations and preferential flow for the two storms suggest that preferential flow is an important transport pathway to the tile drain. ?? ASA, CSSA, SSSA.

  14. Energy Vs. Productivity: Diminishing Returns

    ERIC Educational Resources Information Center

    MOSAIC, 1975

    1975-01-01

    Energy invested in corn production is compared with food energy returned in calculations by David Pimentel at Cornell University. The rate of return is falling off sharply in this already energy-intensive agriculture. Increased energy input, in the form of fertilizer, would yield far greater returns where agriculture is less sophisticated.…

  15. Virtual water flows in the international trade of agricultural products of China.

    PubMed

    Zhang, Yu; Zhang, Jinhe; Tang, Guorong; Chen, Min; Wang, Lachun

    2016-07-01

    With the rapid development of the economy and population, water scarcity and poor water quality caused by water pollution have become increasingly severe in China. Virtual water trade is a useful tool to alleviate water shortage. This paper focuses on a comprehensive study of China's international virtual water flows from agricultural products trade and completes a diachronic analysis from 2001 to 2013. The results show that China was in trade surplus in relation to the virtual water trade of agricultural products. The exported virtual water amounted to 29.94billionm(3)/yr. while 155.55billionm(3)/yr. was embedded in imported products. The trend that China exported virtual water per year was on the decline while the imported was on a rising trend. Virtual water trade of China was highly concentrated. Not all of the exported products had comparative advantages in virtual water content. Imported products were excessively concentrated on water intensive agricultural products such as soya beans, cotton, and palm oil. The exported virtual water mainly flowed to the Republic of Korea, Hong Kong of China and Japan, while the imported mainly flowed from the United States of America, Brazil and Argentina. From the ethical point of view, the trade partners were classified into four types in terms of "net import" and "water abundance": mutual benefit countries, such as Australia and Canada; unilateral benefit countries, such as Mongolia and Norway; supported countries, such as Egypt and Singapore; and double pressure countries, such as India and Pakistan. Virtual water strategy refers to water resources, agricultural products and human beings. The findings are beneficial for innovating water resources management system, adjusting trade structure, ensuring food security in China, and promoting the construction of national ecological security system. PMID:26994788

  16. Long-lasting Science Returns from the Apollo Heat Flow Experiments

    NASA Astrophysics Data System (ADS)

    Nagihara, S.; Taylor, P. T.; Williams, D. R.; Zacny, K.; Hedlund, M.; Nakamura, Y.

    2012-12-01

    The Apollo astronauts deployed geothermal heat flow instruments at landing sites 15 and 17 as part of the Apollo Lunar Surface Experiments Packages (ALSEP) in July 1971 and December 1972, respectively. These instruments continuously transmitted data to the Earth until September 1977. Four decades later, the data from the two Apollo sites remain the only set of in-situ heat flow measurements obtained on an extra-terrestrial body. Researchers continue to extract additional knowledge from this dataset by utilizing new analytical techniques and by synthesizing it with data from more recent lunar orbital missions such as the Lunar Reconnaissance Orbiter. In addition, lessons learned from the Apollo experiments help contemporary researchers in designing heat flow instruments for future missions to the Moon and other planetary bodies. For example, the data from both Apollo sites showed gradual warming trends in the subsurface from 1971 to 1977. The cause of this warming has been debated in recent years. It may have resulted from fluctuation in insolation associated with the 18.6-year-cycle precession of the Moon, or sudden changes in surface thermal environment/properties resulting from the installation of the instruments and the astronauts' activities. These types of re-analyses of the Apollo data have lead a panel of scientists to recommend that a heat flow probe carried on a future lunar mission reach 3 m into the subsurface, ~0.6 m deeper than the depths reached by the Apollo 17 experiment. This presentation describes the authors' current efforts for (1) restoring a part of the Apollo heat flow data that were left unprocessed by the original investigators and (2) designing a compact heat flow instrument for future robotic missions to the Moon. First, at the conclusion of the ALSEP program in 1977, heat flow data obtained at the two Apollo sites after December 1974 were left unprocessed and not properly archived through NASA. In the following decades, heat flow data

  17. Long-Lasting Science Returns from the Apollo Heat Flow Experiments

    NASA Technical Reports Server (NTRS)

    Nagihara, S.; Taylor, P. T.; Williams, D. R.; Zacny, K.; Hedlund, M.; Nakamura, Y.

    2012-01-01

    The Apollo astronauts deployed geothermal heat flow instruments at landing sites 15 and 17 as part of the Apollo Lunar Surface Experiments Packages (ALSEP) in July 1971 and December 1972, respectively. These instruments continuously transmitted data to the Earth until September 1977. Four decades later, the data from the two Apollo sites remain the only set of in-situ heat flow measurements obtained on an extra-terrestrial body. Researchers continue to extract additional knowledge from this dataset by utilizing new analytical techniques and by synthesizing it with data from more recent lunar orbital missions such as the Lunar Reconnaissance Orbiter. In addition, lessons learned from the Apollo experiments help contemporary researchers in designing heat flow instruments for future missions to the Moon and other planetary bodies. For example, the data from both Apollo sites showed gradual warming trends in the subsurface from 1971 to 1977. The cause of this warming has been debated in recent years. It may have resulted from fluctuation in insolation associated with the 18.6-year-cycle precession of the Moon, or sudden changes in surface thermal environment/properties resulting from the installation of the instruments and the astronauts' activities. These types of reanalyses of the Apollo data have lead a panel of scientists to recommend that a heat flow probe carried on a future lunar mission reach 3 m into the subsurface, approx 0.6 m deeper than the depths reached by the Apollo 17 experiment. This presentation describes the authors current efforts for (1) restoring a part of the Apollo heat flow data that were left unprocessed by the original investigators and (2) designing a compact heat flow instrument for future robotic missions to the Moon. First, at the conclusion of the ALSEP program in 1977, heat flow data obtained at the two Apollo sites after December 1974 were left unprocessed and not properly archived through NASA. In the following decades, heat flow

  18. Ditch network sustains functional connectivity and influences patterns of gene flow in an intensive agricultural landscape.

    PubMed

    Favre-Bac, L; Mony, C; Ernoult, A; Burel, F; Arnaud, J-F

    2016-02-01

    In intensive agricultural landscapes, plant species previously relying on semi-natural habitats may persist as metapopulations within landscape linear elements. Maintenance of populations' connectivity through pollen and seed dispersal is a key factor in species persistence in the face of substantial habitat loss. The goals of this study were to investigate the potential corridor role of ditches and to identify the landscape components that significantly impact patterns of gene flow among remnant populations. Using microsatellite loci, we explored the spatial genetic structure of two hydrochorous wetland plants exhibiting contrasting local abundance and different habitat requirements: the rare and regionally protected Oenanthe aquatica and the more commonly distributed Lycopus europaeus, in an 83 km(2) agricultural lowland located in northern France. Both species exhibited a significant spatial genetic structure, along with substantial levels of genetic differentiation, especially for L. europaeus, which also expressed high levels of inbreeding. Isolation-by-distance analysis revealed enhanced gene flow along ditches, indicating their key role in effective seed and pollen dispersal. Our data also suggested that the configuration of the ditch network and the landscape elements significantly affected population genetic structure, with (i) species-specific scale effects on the genetic neighborhood and (ii) detrimental impact of human ditch management on genetic diversity, especially for O. aquatica. Altogether, these findings highlighted the key role of ditches in the maintenance of plant biodiversity in intensive agricultural landscapes with few remnant wetland habitats. PMID:26486611

  19. Investigating summer flow paths in a Dutch agricultural field using high frequency direct measurements

    NASA Astrophysics Data System (ADS)

    Delsman, J. R.; Waterloo, M. J.; Groen, M. M. A.; Groen, J.; Stuyfzand, P. J.

    2014-11-01

    The search for management strategies to cope with projected water scarcity and water quality deterioration calls for a better understanding of the complex interaction between groundwater and surface water in agricultural catchments. We separately measured flow routes to tile drains and an agricultural ditch in a deep polder in the coastal region of the Netherlands, characterized by exfiltration of brackish regional groundwater flow and intake of diverted river water for irrigation and water quality improvement purposes. We simultaneously measured discharge, electrical conductivity and temperature of these separate flow routes at hourly frequencies, disclosing the complex and time-varying patterns and origins of tile drain and ditch exfiltration. Tile drainage could be characterized as a shallow flow system, showing a non-linear response to groundwater level changes. Tile drainage was fed primarily by meteoric water, but still transported the majority (80%) of groundwater-derived salt to surface water. In contrast, deep brackish groundwater exfiltrating directly in the ditch responded linearly to groundwater level variations and is part of a regional groundwater flow system. We could explain the observed salinity of exfiltrating drain and ditch water from the interaction between the fast-responding pressure distribution in the subsurface that determined groundwater flow paths (wave celerity), and the slow-responding groundwater salinity distribution (water velocity). We found water demand for maintaining water levels and diluting salinity through flushing to greatly exceed the actual sprinkling demand. Counterintuitively, flushing demand was found to be largest during precipitation events, suggesting the possibility of water savings by operational flushing control.

  20. A classification of drainage and macropore flow in an agricultural catchment

    NASA Astrophysics Data System (ADS)

    Heppell, C. M.; Worrall, F.; Burt, T. P.; Williams, R. J.

    2002-01-01

    This paper uses a variety of multivariate statistical techniques in order to improve current understanding of the antecedent and rainfall controls on drainage characteristics for an agricultural underdrained clay site. Using the dataset obtained from a two-year hillslope study at Wytham (Oxfordshire, UK) a number of patterns in the nature and style of drainage events were explored. First, using principal components analysis, a distinction was drawn between drainflow controlled by antecedent conditions and drainflow controlled by rainfall characteristics. Dimensional analysis then distinguished between two further types of drainflow event: antecedent limited events (ALE) and non-antecedent limited events (NALE). These were drainflow events requiring a minimum antecedent hydraulic head to occur (ALE) and events that occurred in response to rainfall irrespective of the antecedent conditions, because the rainfall was either of high enough intensity or duration to prompt a response in drainflow (NALE). 2. The dataset also made possible a preliminary investigation into the controls on and types of macropore flow at the site. Principal components analysis identified that rainfall characteristics were more important than antecedent conditions in generating high proportions of macropore flow in drainflow. Of the rainfall characteristics studied, rainfall amount and intensity were the dominant controls on the amount of macropore flow, with duration as a secondary control. Two styles of macropore flow were identified: intensity-driven and duration-driven. Intensity-driven events are characterized by rainfall of high intensity and short duration. During such events the amount of macropore flow is proportional to the rainfall intensity and the interaction between macropore and matrix flow is kinetically limited. The second style of macropore flow is characterized by long-duration events. For these events the amount of macropore flow approaches a maximum value whatever the

  1. Trading and non-trading period Internet information flow and intraday return volatility

    NASA Astrophysics Data System (ADS)

    Shen, Dehua; Zhang, Wei; Xiong, Xiong; Li, Xiao; Zhang, Yongjie

    2016-06-01

    This paper employs the news appeared in Baidu News as the proxy for Internet information flow, separates them into trading period and non-trading period information and provides alternative evidence for the Mixture of Distribution Hypothesis (MDH). The empirical results show that the contemporary information can effectively reduce the volatility persistence; meanwhile, the lead information and the aggregate information also show some explanatory power. Some future directions are pointed out in the concluding remarks.

  2. IRIS Observations of Coronal Rain and Prominences: Return Flows of the Chromosphere-Corona Mass Cycle

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Berger, Thomas; Antolin, Patrick; Schrijver, Karel

    2014-06-01

    It has recently been recognized that a mass cycle (e.g., Berger et al. 2011; McIntosh et al. 2012) between the hot, tenuous solar corona and the cool, dense chromosphere underneath it plays an important role in the mass budget and dynamic evolution of the solar atmosphere. Although the corona ultimately loses mass through the solar wind and coronal mass ejections, a fraction of its mass returns to the chromosphere in coronal rain, downflows of prominences, and other as-yet unidentified processes. We present here analysis of joint observations of IRIS, SDO/AIA, and Hinode/SOT of such phenomena. By utilizing the wide temperature coverage (logT: 4 - 7) provided by these instruments combined, we track the coronal cooling sequence (e.g., Schrijver 2001; Liu et al. 2012; Berger et al. 2012) leading to the formation of such material at transition region or chromospheric temperatures (logT: 4 - 5) in the million-degree corona. We compare the cooling times with those expected from the radiative cooling instability. We also measure the kinematics and densities of such downflows and infer their mass fluxes, which are compared to the upward mass fluxes into the corona, e.g., those associated with spicules and flux emergence. Special attention is paid to coronal rain formed near cusp-shaped portions of coronal loops, funnel-shaped prominences at dips of coronal loops, and their respective magnetic environments. With the information about where and when such catastrophic cooling events take place, we discuss the implications for the enigmatic coronal heating mechanisms (e.g., Antolin et al. 2010).

  3. Modelling the effects of recent agricultural land use change on catchment flow and sediment generation

    NASA Astrophysics Data System (ADS)

    Escobar Ruiz, Veronica; Smith, Hugh; Blake, William

    2016-04-01

    Intensive agricultural practices can exacerbate runoff and soil erosion leading to detrimental impacts downstream. Physically-based models have previously been used to assess the impacts on flow and sediment transport in response to land use change, but there has been little investigation of the effect shorter-term changes linked to variations in the extent of cultivated land. The aim of this project is to quantify the impacts on flow generation and sediment transport of different catchment conditions related to both actual recent changes in agricultural land use as well as future change scenarios. To this end, a physically-based distributed hydrological model, SHETRAN was applied in the Blackwater catchment (12 km2) located in south-west England. Land cover was simulated on the basis of satellite-derived land cover maps (1990, 2000 and 2007) as well as a catchment-scale field survey (2011). Soils were represented in the model using five layers for five different soil types in which parameter values were varied in accordance with land use and literature values. Rainfall data (15 min) combined with monthly calculations of evapotranspiration using a simple temperature-based PE model were used to represent contemporary climatic conditions spanning 2010-2014. Calibration was undertaken for selected events during 2011 when land use information was concurrent with available flow and suspended sediment yield data. All land use simulations were then completed for the period 2010-2014 to enable the comparison of model outputs. This contribution will present preliminary results from these land use simulations alongside the effect of several future changes scenarios on catchment flow and sediment generation.

  4. Contribution of base flow to nonpoint source pollution loads in an agricultural watershed

    USGS Publications Warehouse

    Schilling, K.E.; Wolter, C.F.

    2001-01-01

    Nonpoint source pollution of surface water from overland flow, drainage tiles, and ground water discharge is a major cause of water quality impairment in Iowa. Nonpoint source pollution from base flow ground water was estimated in the Walnut Creek watershed by measuring chemical loads of atrazine, nitrate, chloride, and sulfate at 18 tributary creeks and 19 tiles. Loads were measured during a stable base flow period at creeks and files that discharged into Walnut Creek between two stream gauges. Chemical concentrations of atrazine (< 0.1-12 ??g/L), nitrate (0.1 to 15 mg/L, and chloride (1.5 to 26 mg/L) in water were similar for creek and tile samples. Water draining predominantly agricultural row crop areas had much higher concentrations than water draining restored prairie areas. Three methods were used to estimate base flow discharge in the watershed: (1) Darcy flux; (2) watershed discharge budget; and (3) discharge-drainage area; each yielded similar results (31.2 L/s to 62.3 L/s). Base flow loads to the main channel were estimated by subtracting the loads from the upstream gauge; creeks and tiles, from the total load measured at the downstream gauge station. Base flow concentration for atrazine ranged from 0.15 to 0.29 ??g/L and sulfate concentration ranged from 32 to 64 mg/L, whereas concentrations for nitrate and chloride were negative (-1 to -4 mg/L). Calculated base flow concentrations of atrazine and sulfate appeared to be reasonable estimates, but negative concentrations of nitrate and chloride imply either loss of chemical mass in the stream from upstream to downstream sampling points or measurement error. Load data suggest little contribution from base flow pollutants to Walnut Creek water quality, with most of the pollutant load derived from major tributary creeks. Results from this study have implications for determining total maximum daily loads in agricultural watersheds where contributions from point sources (creeks and tiles) can he used to

  5. Shuttle Return-to-Flight IH-108 Aerothermal Test at CUBRC - Flow Field Calibration and CFD

    NASA Technical Reports Server (NTRS)

    Lau, Kei Y.; Holden, Michael

    2010-01-01

    This paper discusses one specific aspect of the Shuttle Retrun-To-Flight IH-108 Aerothermal Test at CUBRC, the test flow field calibration. It showed the versatility of the CUBRC LENS II wind tunnel for an aerothermal test with unique and demanding requirements. CFD analyses were used effectively to extend the test range at the low end of the Mach range. It demonstrated how ground test facility and CFD synergy can be utilitzed iteratively to enhance the confidence in the fedility of both tools. It addressed the lingering concerns of the aerothermal community on use of inpulse facility and CFD analysis. At the conclusion of the test program, members from the NASA Marshall (MSFC), CUBRC and USA (United Space Alliance) Consultants (The Grey Beards) were asked to independently verify the flight scaling data generated by Boeing for flight certification of the re-designed external tank (ET) components. The blind test comparison showed very good results. A more comprehensive discussion of the topics in this paper can be found in Chapter 6 of Reference [1]. The overall aspect of the test program has been discussed in an AIAA paper by Tim Wadhams [2]. The Shuttle Ascent Stack performance and related issues discussed in the Report [1] are not included in this paper. No ITAR data is included in this paper.

  6. Rapid decline and recovery of cerebral blood flow on return to upright posture

    NASA Astrophysics Data System (ADS)

    Zuj, Kathryn; Harvey, D.; Wheaton, L.; Hughson, R. L.

    2006-05-01

    We examined cardiovascular and cerebrovascular regulation during standing. Nine women and nine men completed 10 min supine rest followed by 70 s standing. We also studied the effectiveness of the cardiopulmonary baroreflex (CPBR) during three levels of LBNP (-10,-20,-30mmHg). Mean flow velocity (MFVMCA) from the right middle cerebral artery (MCA, transcranial Doppler ultrasound), mean arterial pressure (MAP, Finapres), blood pressure at the level of the MCA (BPMCA), and heart rate (HR) were monitored. An index of cerebrovascular resistance (CVRi) was calculated by CVRi=BPMCA/MFVMCA. Baseline values for MAP, MFVMCA, BPMCA, CVRi, and HR were not statistically different between men and women (P>0.1). The 'stand' tests resulted in initial decreases in MAP (19.6-40.5%), MFVMCA (13.0-51.5%), BPMCA (54.6-81.0%), CVRi (49.3-73.1%) and an increase in HR (30.1-106.3%). A greater decrease in MFVMCA, as a percentage of baseline, was seen for men (P=0.007). Men also showed a greater percentage change in MAP (P<0.004) and BPMCA(P<0.04). In the subjects studied for CPBR gain, the preliminary data revealed a negative correlation between reduction in MAP and CPBR gain (r=-0.648). Thus, it is possible the gender difference of smaller declines in MAP for women might have been related to relatively greater CPBR gains.

  7. Shuttle Return-to-Flight IH-108 Aerothermal Test at CUBRC - Flow Field Calibration and CFD

    NASA Technical Reports Server (NTRS)

    Lau, Kei Y.; Holden, M. S.

    2011-01-01

    This paper discusses one specific aspect of the Shuttle Retrun-To-Flight IH-108 Aerothermal Test at Calspan-University of Buffalo Research Center (CUBRC), the test flow field calibration. It showed the versatility of the CUBRC Large Energy National Shock Tunnel (LENS) II wind tunnel for an aerothermal test with unique and demanding requirements. CFD analyses were used effectively to extend the test range at the low end of the Mach range. It demonstrated how ground test facility and CFD synergy can be utilitzed iteratively to enhance the confidence in the fedility of both tools. It addressed the lingering concerns of the aerothermal community on use of inpulse facility and CFD analysis. At the conclusion of the test program, members from the NASA Marshall (MSFC), CUBRC and USA (United Space Alliance) Consultants (The Grey Beards) were asked to independently verify the flight scaling data generated by Boeing for flight certification of the re-designed external tank (ET) components. The blind test comparison showed very good results.

  8. Scaling preferential flow processes in agricultural soils affected by tillage and trafficking at the field scale

    NASA Astrophysics Data System (ADS)

    Filipović, Vilim; Coquet, Yves

    2016-04-01

    There is an accumulation of experimental evidences that agricultural soils, at least the top horizons affected by tillage practices, are not homogeneous and present a structure that is strongly dependent on farming practices like tillage and trafficking. Soil tillage and trafficking can create compacted zones in the soil with hydraulic properties and porosity which are different from those of the non-compacted zones. This spatial variability can strongly influence transport processes and initiate preferential flow. Two or three dimensional models can be used to account for spatial variability created by agricultural practices, but such models need a detailed assessment of spatial heterogeneity which can be rather impractical to provide. This logically raises the question whether and how one dimensional model may be designed and used to account for the within-field spatial variability in soil structure created by agricultural practices. Preferential flow (dual-permeability) modelling performed with HYDRUS-1D will be confronted to classical modelling based on the Richards and convection-dispersion equations using HYDRUS-2D taking into account the various soil heterogeneities created by agricultural practices. Our goal is to derive one set of equivalent 1D soil hydraulic parameters from 2D simulations which accounts for soil heterogeneities created by agricultural operations. A field experiment was carried out in two phases: infiltration and redistribution on a plot by uniform sprinkle irrigation with water or bromide solution. Prior to the field experiment the soil structure of the tilled layer was determined along the face of a large trench perpendicular to the tillage direction (0.7 m depth and 3.1 m wide). Thirty TDR probes and tensiometers were installed in different soil structural zones (Δ compacted soil and Γ macroporous soil) which ensured soil water monitoring throughout the experiment. A map of bromide was constructed from small core samples (4 cm diam

  9. A Community Returns to Agriculture

    ERIC Educational Resources Information Center

    Saavedra-Vela, Pilar

    1978-01-01

    Aiming to keep the land in the hands of the people, the Cooperativa del pueblo's first venture of steer grazing on land held communally was abandoned due to financial pressure and the community's social needs. Today its plans include teaching families to grow vegetables for longer periods in an organic manner and developing a marketing…

  10. Simulation of the Effects of Water Withdrawals, Wastewater Return Flows, and Land-Use Change on Streamflow in the Blackstone River Basin, Massachusetts and Rhode Island

    USGS Publications Warehouse

    Barbaro, Jeffrey R.

    2007-01-01

    Streamflow in many parts of the Blackstone River Basin in south-central Massachusetts and northern Rhode Island is altered by water-supply withdrawals, wastewater-return flows, and land-use change associated with a growing population. Simulations from a previously developed and calibrated Hydrological Simulation Program?FORTRAN (HSPF) precipitation-runoff model for the basin were used to evaluate the effects of water withdrawals, wastewater-return flows, and land-use change on streamflow. Most of the simulations were done for recent (1996?2001) conditions and potential buildout conditions in the future when all available land is developed to provide a long-range assessment of the effects of possible future human activities on water resources in the basin. The effects of land-use change were evaluated by comparing the results of long-term (1960?2004) simulations with (1) undeveloped land use, (2) 1995?1999 land use, and (3) potential buildout land use at selected sites across the basin. Flow-duration curves for these land-use scenarios were similar, indicating that land-use change, as represented in the HSPF model, had little effect on flow in the major tributary streams and rivers in the basin. However, land-use change?particularly increased effective impervious area?could potentially have greater effects on the hydrology, water quality, and aquatic habitat of the smaller streams in the basin. The effects of water withdrawals and wastewater-return flows were evaluated by comparing the results of long-term simulations with (1) no withdrawals and return flows, (2) actual (measured) 1996?2001 withdrawals and wastewater-return flows, and (3) potential withdrawals and wastewater-return flows at buildout. Overall, the results indicated that water use had a much larger effect on streamflow than did land use, and that the location and magnitude of wastewater-return flows were important for lessening the effects of withdrawals on streamflow in the Blackstone River Basin

  11. Integrated Modelling on Flow and Water Quality Under the Impacts of Climate Change and Agricultural Activities

    NASA Astrophysics Data System (ADS)

    SHI, J.

    2014-12-01

    Climate change is expected to have a significant impact on flooding in the UK, inducing more intense and prolonged storms. Frequent flooding due to climate change already exacerbates catchment water quality. Land use is another contributing factor to poor water quality. For example, the move to intensive farming could cause an increase in faecal coliforms entering the water courses. In an effort to understand better the effects on water quality from land use and climate change, the hydrological and estuarine processes are being modelled using SWAT (Soil and Water Assessment Tool), linked to a 2-D hydrodynamic model DIVAST(Depth Integrated Velocity and Solute Transport). The coupled model is able to quantify how much of each pollutant from the catchment reaches the harbour and the impact on water quality within the harbour. The work is focused on the transportation and decay of faecal coliforms from agricultural runoff into the rivers Frome and Piddle in the UK. The impact from the agricultural land use and activities on the catchment river hydrology and water quality are evaluated. The coupled model calibration and validation showed the good model performance on flow and faecal coliform in the watershed and estuary.

  12. Estimating nutrient releases from agriculture in China: an extended substance flow analysis framework and a modeling tool.

    PubMed

    Chen, M; Chen, J; Sun, F

    2010-10-01

    Agriculture related pollution has attracted the attention of policy makers as well as scientists in China as its contribution to water impairment has increased, and quantitative information at the national and regional levels is being sought to support decision making. However, traditional approaches are either time-consuming, expensive (e.g. national surveys) or oversimplified and crude (e.g. coefficient methods). Therefore, this study proposed an extended substance flow analysis (SFA) framework to estimate nutrient releases from agricultural and rural activities in China by depicting the nutrient flows in Chinese agro-ecosystems. The six-step process proposed herein includes: (a) system definition; (b) model development; (c) database development; (d) model validation; (e) results interpretation; and (f) uncertainty analysis. The developed Eubolism (Elementary Unit based nutrient Balance mOdeLIng in agro-ecoSysteM) model combined a nutrient balance module with an emission inventory module to quantify the nutrient flows in the agro-ecosystem. The model was validated and then applied to estimate the total agricultural nutrient loads, identify the contribution of different agricultural and rural activities and different land use types to the total loads, and analyze the spatial pattern of agricultural nutrient emissions in China. These results could provide an entire picture of agricultural pollution at the national level and be used to support policy making. Furthermore, uncertainties associated with the structure of the elementary units, spatial resolution, and inputs/parameters were also analyzed to evaluate the robustness of the model results. PMID:20691463

  13. 7 CFR 356.8 - Return procedure.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Return procedure. 356.8 Section 356.8 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FORFEITURE PROCEDURES § 356.8 Return procedure. If, at the conclusion...

  14. Characterization of flow and infiltration processes on agricultural plots irrigated by submersion.

    NASA Astrophysics Data System (ADS)

    Alkassem Alosman, Mohamed; Ruy, Stéphane; Olioso, Albert; Bader, Jean Claude; Buis, Samuel; Lecharpentier, Patrice; Charron, Francois

    2015-04-01

    The surface irrigation (flood irrigation, trickle and furrow) is a traditional irrigation system widely used worldwide. This system is recognized as being highly water consumer: high volumes of water are injected to the plot, which generate significant loss of water (drainage and run-off). Although these unused water flows can generate positive externalities (feeding wetlands, groundwater recharge) a decrease of water volume used is sought in a context of limited water resource. In this system of irrigation, the amount of water that is actually brought to the plot surface ("irrigation dose") is insufficiently known because it depends on the interaction between the propagation of water at surface of the plot and its infiltration into the soil. These two processes are conditioned by multiple factors: input flow rate in the plot, irrigation duration, soil properties (hydraulic conductivity, water reserve and depth), geometry of the parcel, hydraulic factors (slope of flow, coefficient of friction hydraulic). A methodology is therefore needed for calculating the doses given on an agricultural plot in order to analyse current practices and to propose ways for optimization. The aim of this study is to develop a methodology to estimate (i) the amount of infiltrated water at the scale of a flood irrigated agricultural field, and (ii) soil properties (permeability, useful water reserve). This work is based on the use of a flood irrigation model (CALHY, model Bader et al., 2010, Hydrol. Sci. J., 55, 177-191) combined with a device for tracking the infiltration and the advancing of water in several fields of hay which are irrigated through submersion. Firstly, a sensitivity analysis was used to define an optimal experimental configuration with respect to the estimation of parameters of interest (hydraulic friction, soil water storage capacity, hydraulic conductivity, soil depth). This analysis was performed on each of the model parameters and for different output variables

  15. Seventeenth century organic agriculture in China: II. Energy flows through an agroecosystem in Jiaxing Region

    SciTech Connect

    Dazhong, W.; Pimentel, D.

    1986-03-01

    The energy flows in a seventeenth century agroecosystem in Jiaxing Region of eastern China were analyzed on the basis of historical data. The agroecosystem included cropping, mulberry-silkworm livestock, and fishing systems. In terms of energy, the agroecosystem was sustainable. Human labor provided all the power with inputs of about 3700 hr per hectare of farmland. Most or 70% of the labor was expended in the cropping system. Human and animal manure provided most of the nutrients for crop and mulberry production. About two-thirds of the total manure was used in crop production and one-third in the mulberry plantations. The only fossil energy input was a few hand tools. Approximately 55% of the grain was consumed directly by local residents, about one-third of the grain was used to make an alcohol drink and produce distillers' grains, which was fed to pigs, and only 2% of the grains were exported outside the agroecosystem. About two-thirds of the harvested crop residues were used as household fuel, while the remainder was returned to the field as an organic fertilizer. Pork accounted for 85% and silk cocoons 14% of the total animal products produced. Even though the agroecosystem was generally sustainable in terms of energy, the major environmental problem was that two-thirds of the harvested crop residues were used for household fuel. This reduced nutrient cycling in the system. Insufficient land was available to produce fuelwood; thus, crop residues were the primary source of fuel for the people.

  16. Methods to determine transit losses for return flows of transmountain water in Fountain Creek between Colorado Springs and the Arkansas River, Colorado

    USGS Publications Warehouse

    Kuhn, Gerhard

    1988-01-01

    Methods were developed by which transit losses could be determined for transmountain return flows in Fountain Creek between Colorado Springs, Colorado, and its confluence with the Arkansas River. The study reach is a complex hydrologic system wherein a substantially variable streamflow interacts with an alluvial aquifer. The study approach included: (1) calibration and verification of a streamflow-routing model that contained a bank-storage-discharge component; (2) use of the model to develop the methods by which transit losses could be calculated; and (3) design of an application method for calculating daily transit loss using the model results. Sources of transit losses that were studied are bank storage, channel storage, and evaporation. Magnitude of bank-storage loss primarily depends on duration of a recovery period during which water lost to bank storage is returned to the stream. Net loss to bank storage can vary from about 50% for a 0-day recovery period to about 2% for a 180-day recovery period. Virtually all water lost to bank storage could be returned to the stream with longer recovery periods. Channel-storage loss was determined to be about 10% of a release quantity. Because the loss on any given day is totally recovered in the form of gains from channel storage on the subsequent day, channel storage is a temporary transit loss. Evaporation loss generally is less than 5% of a given daily transmountain return-flow release, depending on month of year. Evaporation losses are permanently lost from the system. (USGS)

  17. Agricultural practices influence flow regimes of headwater streams in western Iowa.

    PubMed

    Tomer, M D; Meek, D W; Kramer, L A

    2005-01-01

    Agricultural tillage influences runoff and infiltration, but consequent effects on watershed hydrology are poorly documented. This study evaluated 25 yr (1971-1995) hydrologic records from four first-order watersheds in Iowa's loess hills. Two watersheds were under conventional tillage and two were under conservation (ridge) tillage, one of which was terraced. All four watersheds grew corn (Zea mays L.) every year. Flow-frequency statistics and autoregressive modeling were used to determine how conservation treatments influenced stream hydrology. The autoregressive modeling characterized variations in discharge, baseflow, and runoff at multi-year, annual, and shorter time scales. The ridge-tilled watershed (nonterraced) had 47% less runoff and 36% more baseflow than the conventional watershed of similar landform and slope. Recovery of baseflow after drought was quicker in the conservation watersheds, as evidenced by 365-d moving average plots, and 67% greater baseflow during the driest 2 yr. The two conventional watersheds were similar, except the steeper watershed discharged more runoff and baseflow during short (<30 d), wet periods. Significant multi-year and annual cycles occurred in all variables. Under ridge-till, seasonal (annual-cycle) variations in baseflow had greater amplitude, showing the seasonality of subsurface contaminant movement could increase under conservation practices. However, deviations from the modeled cycles of baseflow were also more persistent under conservation practices, indicating baseflow was more stable. Indeed, flow-frequency curves showed wet-weather discharge decreased and dry-weather discharge increased under conservation practices. Although mean discharge increased in the conservation watersheds, variance and skewness of daily values were smaller. Ridge tillage with or without terraces increased stream discharge but reduced its variability. PMID:16091607

  18. Irrigation-dependent wetlands versus instream flow enhancement: economics of water transfers from agriculture to wildlife uses.

    PubMed

    Peck, Dannele E; McLeod, Doanald M; Hewlett, John P; Lovvorn, James R

    2004-12-01

    Irrigated agriculture throughout western North America faces increasing pressure to transfer water to nonagricultural uses, including instream flows for fish and wildlife management. In an important case, increased instream flows are needed in Nebraska's Platte River for recovery of threatened and endangered fish and wildlife species. Irrigated agriculture in the Laramie Basin of southeast Wyoming is a potential water source for the effort to enhance instream flow. However, flood irrigation of hayfields in the Laramie Basin has created many wetlands, both ephemeral and permanent, over the last century. Attempting to increase Platte River instream flows by purchasing water rights or improving irrigation efficiency in the Laramie Basin would transform irrigated agriculture, causing a substantial fraction of the Laramie Basin's wetlands to be lost. A creative solution is needed to prevent the sacrifice of one ecosystem on behalf of another. A rotating short-term water-leasing program is proposed. The program allows Laramie Basin producers to contribute to instream flows while continuing to support local wetlands. Permanent wetland desiccation is prevented and regional environmental water needs are met without impairing local ecological resources. Budget analysis is used to provide an initial cost estimate for acquiring water from agriculture through the short-term leasing program. The proposed approach is more expensive than traditional programs but allows contribution to instream flows without major wetland loss. Short-term leasing is a more efficient approach if benefits from wetlands exceed the difference in cost between the short-term lease program and programs that do not conserve wetlands. PMID:15633027

  19. Estimation of water withdrawal and distribution, water use, and wastewater collection and return flow in Cumberland, Rhode Island, 1988. Water resources investigation

    SciTech Connect

    Horn, M.A.; Craft, P.A.; Bratton, L.

    1994-12-31

    The purpose of the report is to demonstrate integration of water-use data collected by different State agencies or maintained by different public suppliers and wastewater-treatment facilities. The report presents a brief discussion of data compilation, organization and computer storage, and analysis. A detailed description of the methods used and the resulting water-use data are presented on withdrawal, distribution, use, wastewater collection, return flow, and import of water into and export of water out of Cumberland. At the end of each section, an overview provides a discussion of how water that is withdrawn, distributed, used, collected, and returned in the study area affects the availability and distribution of water resources.

  20. Food, Feed, or Fuel? Phosphorus Flows Embodied in US Agricultural Production and Trade

    NASA Astrophysics Data System (ADS)

    MacDonald, G.; Bennett, E.; Carpenter, S.

    2012-12-01

    Agricultural phosphorus (P) use is integral to sustainable food production and water quality regulation. Globalization of agricultural systems, changing diets, and increasing biofuel production pose new challenges for managing non-renewable P reserves, particularly in key agricultural producing regions such as the US. We used a detailed model of the US agricultural system to assess the quantity of mineral P fertilizers used to produce food crops, livestock, and biofuels relative to the P ultimately consumed in domestic diets. We also quantified linkages in fertilizer use between the US and its trading partners globally via agricultural trade. Feed and livestock production drove by far the largest demand for P fertilizers in the US (56% of all P use for domestic and imported products). Of the total mineral P inputs to US domestic agriculture in 2007 (1905 Gg P), 28% were retained in agricultural soils as surplus P, 40% were lost through processing and waste prior to consumption in human diets, while 10% were diverted directly to biofuel production. One quarter of P fertilizer in the US was required to produce exports, particularly major food and feed crops (corn, soybean, and wheat) that drove a large net P flux out of the country (338 Gg P) with strongly crop-specific effects on soil P imbalances nationally. However, US meat consumption involved considerable reliance on P fertilizer use in other countries to produce red meat imports linked primarily to soil P surpluses abroad. We show that changes in domestic farm management and consumer waste could together reduce the P fertilizer needed to produce food consumed in the US by half, which is comparable to the P fertilizer reduction attainable by cutting domestic meat consumption (44%). More effective distribution of P use for major crops nationally and greater recycling of all agricultural wastes is critical to using US phosphate rock reserves as efficiently as possible while maintaining export-oriented agriculture.

  1. Migratory Patterns of Wild Chinook Salmon Oncorhynchus tshawytscha Returning to a Large, Free-Flowing River Basin

    PubMed Central

    Eiler, John H.; Evans, Allison N.; Schreck, Carl B.

    2015-01-01

    Upriver movements were determined for Chinook salmon Oncorhynchus tshawytscha returning to the Yukon River, a large, virtually pristine river basin. These returns have declined dramatically since the late 1990s, and information is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio tagged during 2002–2004. Most (97.5%) of the fish tracked upriver to spawning areas displayed continual upriver movements and strong fidelity to the terminal tributaries entered. Movement rates were substantially slower for fish spawning in lower river tributaries (28–40 km d-1) compared to upper basin stocks (52–62 km d-1). Three distinct migratory patterns were observed, including a gradual decline, pronounced decline, and substantial increase in movement rate as the fish moved upriver. Stocks destined for the same region exhibited similar migratory patterns. Individual fish within a stock showed substantial variation, but tended to reflect the regional pattern. Differences between consistently faster and slower fish explained 74% of the within-stock variation, whereas relative shifts in sequential movement rates between “hares” (faster fish becoming slower) and “tortoises” (slow but steady fish) explained 22% of the variation. Pulses of fish moving upriver were not cohesive. Fish tagged over a 4-day period took 16 days to pass a site 872 km upriver. Movement rates were substantially faster and the percentage of atypical movements considerably less than reported in more southerly drainages, but may reflect the pristine conditions within the Yukon River, wild origins of the fish, and discrete run timing of the returns. Movement data can provide numerous insights into the status and management of salmon returns, particularly in large river drainages with widely scattered fisheries where management actions in the lower river potentially impact harvests and escapement farther upstream. However, the substantial variation

  2. Migratory Patterns of Wild Chinook Salmon Oncorhynchus tshawytscha Returning to a Large, Free-Flowing River Basin.

    PubMed

    Eiler, John H; Evans, Allison N; Schreck, Carl B

    2014-01-01

    Upriver movements were determined for Chinook salmon Oncorhynchus tshawytscha returning to the Yukon River, a large, virtually pristine river basin. These returns have declined dramatically since the late 1990s, and information is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio tagged during 2002-2004. Most (97.5%) of the fish tracked upriver to spawning areas displayed continual upriver movements and strong fidelity to the terminal tributaries entered. Movement rates were substantially slower for fish spawning in lower river tributaries (28-40 km d-1) compared to upper basin stocks (52-62 km d-1). Three distinct migratory patterns were observed, including a gradual decline, pronounced decline, and substantial increase in movement rate as the fish moved upriver. Stocks destined for the same region exhibited similar migratory patterns. Individual fish within a stock showed substantial variation, but tended to reflect the regional pattern. Differences between consistently faster and slower fish explained 74% of the within-stock variation, whereas relative shifts in sequential movement rates between "hares" (faster fish becoming slower) and "tortoises" (slow but steady fish) explained 22% of the variation. Pulses of fish moving upriver were not cohesive. Fish tagged over a 4-day period took 16 days to pass a site 872 km upriver. Movement rates were substantially faster and the percentage of atypical movements considerably less than reported in more southerly drainages, but may reflect the pristine conditions within the Yukon River, wild origins of the fish, and discrete run timing of the returns. Movement data can provide numerous insights into the status and management of salmon returns, particularly in large river drainages with widely scattered fisheries where management actions in the lower river potentially impact harvests and escapement farther upstream. However, the substantial variation exhibited among

  3. Analysis of Employment Flow of Landscape Architecture Graduates in Agricultural Universities

    ERIC Educational Resources Information Center

    Yao, Xia; He, Linchun

    2012-01-01

    A statistical analysis of employment flow of landscape architecture graduates was conducted on the employment data of graduates major in landscape architecture in 2008 to 2011. The employment flow of graduates was to be admitted to graduate students, industrial direction and regional distribution, etc. Then, the features of talent flow and factors…

  4. 7 CFR 3560.305 - Return on investment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI)...

  5. 7 CFR 3560.305 - Return on investment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI)...

  6. 7 CFR 3560.305 - Return on investment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI)...

  7. Controls of evaporative irrigation return flows in comparison to seawater intrusion in coastal karstic aquifers in northern Sri Lanka: Evidence from solutes and stable isotopes.

    PubMed

    Chandrajith, Rohana; Diyabalanage, Saranga; Premathilake, K M; Hanke, Christian; van Geldern, Robert; Barth, Johannes A C

    2016-04-01

    Groundwater in Miocene karstic aquifers in the Jaffna Peninsula of Sri Lanka is an important resource since no other fresh water sources are available in the region. The subsurface is characterized by highly productive limestone aquifers that are used for drinking and agriculture purposes. A comprehensive hydrogeochemical study was carried out to reveal the processes affecting the groundwater quality in this region. Major and trace element composition and environmental isotope ratios of oxygen and hydrogen (δ(18)OH2O and δ(2)HH2O) were determined in 35 groundwater samples for this investigation. The ion abundance of groundwater in the region was characterized by an anion sequence order with HCO3->Cl->SO4->NO3-. For cations, average Na(+)+K(+) contents in groundwater exceeded those of Ca(2+)+Mg(2+) in most cases. Ionic relationships of major solutes indicated open system calcite dissolution while seawater intrusions are also evident but only close to the coast. The solute contents are enriched by agricultural irrigation returns and associated evaporation. This was confirmed by the stable isotope composition of groundwater that deviated from the local meteoric water line (LMWL) and formed its own regression line denoted as the local evaporation line (LEL). The latter can be described by δ(2)HH2O=5.8×δ(18)OH2O -- 2.9. Increased contents of nitrate-N (up to 5mg/L), sulfate (up to 430mg/L) and fluoride (up to 1.5mg/L) provided evidences for anthropogenic inputs of solutes, most likely from agriculture activities. Among trace elements Ba, Sr, As and Se levels in the Jaffna groundwater were higher compared to that of the dry zone metamorphic aquifers in Sri Lanka. Solute geochemistry and stable isotope evidences from the region indicates that groundwater in the area is mainly derived from local modern precipitation but modified heavily by progressive evaporative concentration rather than seawater intrusion. PMID:26803741

  8. 7 CFR 3560.68 - Permitted return on investment (ROI).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Permitted return on investment (ROI). 3560.68 Section 3560.68 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, DEPARTMENT OF AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Direct Loan and Grant Origination § 3560.68 Permitted return on investment...

  9. Prehistoric Agriculture and Soil Fertility on Lava Flows in Northern Arizona, USA: Results from the San Francisco Volcanic Field REU

    NASA Astrophysics Data System (ADS)

    Broadman, E.; Anderson, K. C.

    2013-12-01

    The San Francisco Volcanic Field in northern Arizona is home to ~600 cinder cones, the youngest of which is Sunset Crater (erupted ~AD 1100). This study documents trends in available phosphate and nitrate content with time, testing whether lowered soil pH from the addition of Sunset cinders increased soil fertility and became a factor in Anasazi agricultural success. Soil fertility is examined both before and after Sunset's eruption in soils of different ages that have developed from eolian deposition on top of lava flows. An increase in phosphate and nitrate levels following acidification would suggest that the presence of Sunset cinders brought the soils to the optimal pH for mobilization of these nutrients. The combined effects of the cinder layer retaining nutrients and water, wetter climates, and increases in phosphate and nitrate (both limiting nutrients for plant growth), would have contributed to Anasazi agricultural success after Sunset's eruption. Samples for this study were taken from eolian-derived soils of different ages atop lava flows in the San Francisco Volcanic Field. OSL data from these soils on Strawberry and SP Craters' lava flows yielded age estimates of ~12.3 ka (Strawberry) and ~32.7 ka (SP), on which a soil chronosequence was based. Results from the chronosequence supported these OSL ages, indicating that soils on the SP flow are older than those on the Strawberry flow. Field descriptions, Harden Development Indices, particle size analysis, and nutrient content analysis were used for this aspect of the project. An experimental acid wash method will be used to simulate the addition of Sunset's acidic cinders, and will yield data for phosphate and nitrate content after Sunset erupted. Preliminary results indicate that phosphate and nitrate accumulate in upper, eolian-derived horizons (Av, Bw) and in more deeply buried carbonate horizons (Bk). Higher concentrations of phosphate and nitrate were found in older (SP) soils than younger

  10. Cryptic diversity and gene flow among three African agricultural pests: Ceratitis rosa, Ceratitis fasciventris and Ceratitis anonae (Diptera, Tephritidae).

    PubMed

    Virgilio, M; Delatte, H; Quilici, S; Backeljau, T; De Meyer, M

    2013-05-01

    The 'Ceratitis FAR complex' is a species complex of African fruit flies (Diptera, Tephritidae) including the major agricultural pest Ceratitis rosa and the morphologically similar Ceratitis fasciventris and Ceratitis anonae. To resolve their intra- and interspecific genetic relationships and to estimate gene flow within this complex, we surveyed allelic variation at 16 microsatellite loci in 27 African populations of the three morphospecies. Interpopulation genetic distances and individual Bayesian assignments distinguished five genotypic clusters: two involving C. rosa (R1, R2; that may occur in sympatry), two involving C. fasciventris (F1, F2; with parapatric distributions) and one involving C. anonae (A). Intra- and interspecific patterns of genetic differentiation were not hierarchically structured and genetic differentiation between conspecific clusters (F1-F2 and R1-R2) was higher or comparable with differentiation between heterospecific clusters (e.g. F1-A or R2-A). In some cases, gene flow estimates among morphospecies or among heterospecific genotypic clusters were significantly different from zero, showing the lack of reproductive isolation. Genetic differentiation between genotypic clusters was partly supported by morphological differences observed a posteriori in male secondary sexual characters. These results suggest important revisions to current models of ecological niche requirements and invasion risk of the major agricultural pest C. rosa and provide a basis for a taxonomic re-interpretation of the FAR complex. PMID:23506441

  11. Estimation of water withdrawal and distribution, water use, and wastewater collection and return flow in Cumberland, Rhode Island, 1988

    USGS Publications Warehouse

    Horn, M.A.; Craft, P.A.; Bratton, Lisa

    1994-01-01

    Water-use data collected in Rhode Island by different State agencies or maintained by different public suppliers and wastewater- treatment facilities need to be integrated if these data are to be used in making water- resource management decisions. Water-use data for the town of Cumberland, a small area in northeastern Rhode Island, were compiled and integrated to provide an example of how the procedure could be applied. Integration and reliability assessment of water-use data could be facilitated if public suppliers, wastewater- treatment facilities, and State agencies used a number of standardized procedures for data collection and computer storage. The total surface water and ground water withdrawn in the town of Cumberland during 1988 is estimated to be 15.39 million gallons per day, of which 11.20 million gallons per day was exported to other towns. Water use in Cumberland included 2.51 million gallons per day for domestic use, 0.68 million gallons per day for industrial use, 0.27 million gallons per day for commercial use, and 0.73 million gallons per day for other use, most of which were unmetered use. Disposal of waste- water in Cumberland included 2.03 million gallons per day returned to the hydrologic system and 1.73 million gallons per day exported from Cumberland for wastewater treatment. Consumptive use during 1988 is estimated to be 0.43 million gallons per day.

  12. Stable isotope and groundwater flow dynamics of agricultural irrigation recharge into groundwater resources of the Central Valley, California

    SciTech Connect

    Davisson, M.L.; Criss, R.E.

    1995-01-01

    Intensive agricultural irrigation and overdraft of groundwater in the Central Valley of California profoundly affect the regional quality and availability of shallow groundwater resources. In the natural state, the {delta}{sup 18}O values of groundwater were relatively homogeneous (mostly -7.0 {+-} 0.5{per_thousand}), reflecting local meteoric recharge that slowly (1-3m/yr) flowed toward the valley axis. Today, on the west side of the valley, the isotope distribution is dominated by high {sup 18}O enclosures formed by recharge of evaporated irrigation waters, while the east side has bands of low {sup 18}O groundwater indicating induced recharge from rivers draining the Sierra Nevada mountains. Changes in {delta}{sup 18}O values caused by the agricultural recharge strongly correlate with elevated nitrate concentrations (5 to >100 mg/L) that form pervasive, non-point source pollutants. Small, west-side cities dependent solely on groundwater resources have experienced increases of >1.0 mg/L per year of nitrate for 10-30 years. The resultant high nitrates threaten the economical use of the groundwater for domestic purposes, and have forced some well shut-downs. Furthermore, since >80% of modern recharge is now derived from agricultural irrigation, and because modern recharge rates are {approximately}10 times those of the natural state, agricultural land retirement by urbanization will severely curtail the current safe-yields and promote overdraft pumping. Such overdrafting has occurred in the Sacramento metropolitan area for {approximately}40 years, creating cones of depression {approximately}25m deep. Today, groundwater withdrawal in Sacramento is approximately matched by infiltration of low {sup 18}O water (-11.0{per_thousand}) away from the Sacramento and American Rivers, which is estimated to occur at 100-300m/year from the sharp {sup 18}O gradients in our groundwater isotope map.

  13. Municipal water reuse for urban agriculture in Namibia: Modeling nutrient and salt flows as impacted by sanitation user behavior.

    PubMed

    Woltersdorf, L; Scheidegger, R; Liehr, S; Döll, P

    2016-03-15

    Adequate sanitation, wastewater treatment and irrigation infrastructure often lacks in urban areas of developing countries. While treated, nutrient-rich reuse water is a precious resource for crop production in dry regions, excessive salinity might harm the crops. The aim of this study was to quantify, from a system perspective, the nutrient and salt flows a new infrastructure connecting water supply, sanitation, wastewater treatment and nutrient-rich water reuse for the irrigation of agriculture, from a system perspective. For this, we developed and applied a quantitative assessment method to understand the benefits and to support the management of the new water infrastructure in an urban area in semi-arid Namibia. The nutrient and salt flows, as affected by sanitation user behavior, were quantified by mathematical material flow analysis that accounts for the low availability of suitable and certain data in developing countries, by including data ranges and by assessing the effects of different assumptions in cases. Also the nutrient and leaching requirements of a crop scheme were calculated. We found that, with ideal sanitation use, 100% of nutrients and salts are reclaimed and the slightly saline reuse water is sufficient to fertigate 10 m(2)/cap/yr (90% uncertainty interval 7-12 m(2)/cap/yr). However, only 50% of the P contained in human excreta could be finally used for crop nutrition. During the pilot phase fewer sanitation users than expected used slightly more water per capita, used the toilets less frequently and practiced open defecation more frequently. Therefore, it was only possible to reclaim about 85% of nutrients from human excreta, the reuse water was non-saline and contained less nutrient so that the P was the limiting factor for crop fertigation. To reclaim all nutrients from human excreta and fertigate a larger agricultural area, sanitation user behavior needs to be improved. The results and the methodology of this study can be generalized and

  14. Overland flow and sediment transport in an agricultural lowland catchments: a focus on tile drain export

    NASA Astrophysics Data System (ADS)

    Vandromme, Rosalie; Grangeon, Thomas; Cerdan, Olivier; Manière, Louis; Salvador Blanes, Sébastien; Foucher, Anthony; Chapalain, Marion; Evrard, Olivier; Le Gall, Marion

    2016-04-01

    Rural landscapes have been extensively modified by human activities in Western Europe since the beginning of the 20th century in order to intensify agricultural production. Cultivated areas often expanded at the expense of grassland and wetlands located in lowland areas (de Groot et al., 2002). Therefore, large modifications were made to the agricultural landscapes: stream redesign, land consolidation, removal of hedges, and installation of tile drainage networks to drain the hydromorphic soils. These changes modified sediment processes and resulted in large morphological alterations (e.g. channel bed incision, deposition of fine sediment, channel bank erosion). Accordingly, these alterations threaten water quality and prevent to meet the requirements of the European directives. Improving water quality requires a clear understanding of the hydrosedimentary dynamics in these lowland cultivated catchments. However, few studies were conducted in drained environments. To fill this research gap, a pilot study was started in cultivated catchment of the Loire River basin, France, where tile drain densities are very high (> 1.5 km/km²). Six hydro-sedimentary monitoring stations were installed in the Louroux catchment (24 km²). One of them was specifically dedicated to measuring water/sediment fluxes from tile drains. Water level and turbidity were continuously monitored and sediments were sampled during floods and low stage periods. Samples were measured for particle size distribution, and sediment tracing studies are currently being developed to quantify the contribution of potential sources (e.g. surface vs subsurface, lithologies) to river sediment. Hydro-sedimentary fluxes were quantified and modelled for some selected events. The catchment hydrosedimentary fluxes and their properties were shown to be impacted by tile drain sediment transport, especially regarding particle size distribution, with the dominant export of very fine particles (< 2 μm) from tile drains

  15. Effect of subsurface flow on nutrient transport between a eutrophic coastal lake and agricultural reclamation land

    NASA Astrophysics Data System (ADS)

    Onodera, S. I.; Saito, M.; Jin, G.; Hayakawa, A.; Maruyama, Y.

    2014-12-01

    We examined to confirm the effect of surface water-groundwater interaction on the nutrient transport in Hachiro-gata Lake of coastal Akita prefecture and nutrient transport with the water flow. The area of Hachiro-gata lake have decreased since 1960s due to the land reclamation. The reclamation land covered mainly at the east and south side to the Hachiro-gata Lake. The elevation of the reclamation land is about 3m lower than the lake water level. It suggests water flow in the underground between the lake and land would have the stable direction from the lake to the land. Because the eutrophication often occurs in Hachiro-gata Lake, the nutrient would be accumulated in sediment. We installed three piezometers at the bankside of the lake and reclamation land, respectively. The water levels were monitored from September to December in 2013 and May to August in 2014. In addition, water samples were collected in September and December in 2013, May in 2014. We confirmed water flow from the lake to the land with the hydraulic gradient from 0.05 to 0.1. In addition, DOC and phosphorus concentrations of groundwater were higher in the land than in the lake water. The lake water has recently eutrophic condition, and so many organic matter originated from phytoplankton are deposited. The porewater in the lake sediment near the bank had the high nutrient and DOC concentrations. Based on this research, we can make a hypothesis of nutrient transport from the lake to the land with groundwater flow.

  16. Mechanism and rate of denitrification in an agricultural watershed: Electron and mass balance along groundwater flow paths

    USGS Publications Warehouse

    Tesoriero, A.J.; Liebscher, H.; Cox, S.E.

    2000-01-01

    The rate and mechanism of nitrate removal along and between groundwater flow paths were investigated using a series of well nests screened in an unconfined sand and gravel aquifer. Intensive agricultural activity in this area has resulted in nitrate concentrations in groundwater often exceeding drinking water standards. Both the extent and rate of denitrification varied depending on the groundwater flow path. While little or no denitrification occurred in much of the upland portions of the aquifer, a gradual redox gradient is observed as aerobic upland groundwater moves deeper in the aquifer. In contrast, a sharp shallow redox gradient is observed adjacent to a third-order stream as aerobic groundwater enters reduced sediments. An essentially complete loss of nitrate concurrent with increases in excess N2 provide evidence that denitrification occurs as groundwater enters this zone. Electron and mass balance calculations suggest that iron sulfide (e.g., pyrite) oxidation is the primary source of electrons for denitrification. Denitrification rate estimates were based on mass balance calculations using nitrate and excess N2 coupled with groundwater travel times. Travel times were determined using a groundwater flow model and were constrained by chlorofluorocarbon-based age dates. Denitrification rates were found to vary considerably between the two areas where denitrification occurs. Denitrification rates in the deep, upland portions of the aquifer were found to range from < 0.01 to 0.14 mM of N per year; rates at the redoxcline along the shallow flow path range from 1.0 to 2.7 mM of N per year. Potential denitrification rates in groundwater adjacent to the stream may be much faster, with rates up to 140 mM per year based on an in situ experiment conducted in this zone.The rate and mechanism of nitrate removal along and between groundwater flow paths were investigated using a series of well nests screened in an unconfined sand and gravel aquifer. Intensive

  17. Tatanka Returns.

    ERIC Educational Resources Information Center

    Simonelli, Richard

    1993-01-01

    Describes efforts of the InterTribal Bison Cooperative (Rapid City, SD) to reintroduce the buffalo for cultural purposes to American Indian reservations. Explains how the buffalo's return is contributing to community wellness. Discusses career opportunities for both Native and non-Native people in buffalo management. (LP)

  18. Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow

    USGS Publications Warehouse

    Wildman, R.A., Jr.; Domagalski, J.L.; Hering, J.G.

    2009-01-01

    The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural irrigation. Filtered ground water samples were collected from 30 drive point locations in March, June, and October 2004. Hydrologic processes, described previously, were verified by observations of bromine concentrations; manganese was used to indicate redox conditions. The separate responses of the minor solutes strontium, barium, uranium, and phosphorus to these influences were examined. Correlation and principal component analyses indicate that hydrologic processes dominate the distribution of trace elements in the ground water. Redox conditions appear to be independent of hydrologic processes and account for most of the remaining data variability. With some variability, major processes are consistent in two sampling transects separated by 100 m. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  19. MODFLOW-2000, the U.S. Geological Survey Modular Ground-Water Model; documentation of packages for simulating evapotranspiration with a segmented function (ETS1) and drains with return flow (DRT1)

    USGS Publications Warehouse

    Banta, Edward R.

    2000-01-01

    Two new packages for the U.S. Geological Survey modular finite-difference ground-water-flow model MODFLOW-2000 are documented. The new packages provide flexibility in simulating evapotranspiration and drain features not provided by the MODFLOW-2000 Evapotranspiration (EVT) and Drain (DRN) Packages. The report describes conceptualization of the packages, input instructions, listings and explanations of the source code, and example simulations. The new Evapotranspiration Segments (ETS 1) Package allows simulation of evapotranspiration with a user-defined relation between evapotranspiration rate and hydraulic head. This capability provides a degree of flexibility not supported by the EVT Package, which has been available in MODFLOW since its initial release. In the ETS 1 Package, the relation of evapotranspiration rate to hydraulic head is conceptualized as a segmented line between an evaporation surface, defined as the elevation where the evapotranspiration rate reaches a maximum, and an elevation located at an extinction depth below the evaporation surface, where the evapotranspiration rate reaches zero. The user supplies input to define as many intermediate segment endpoints as desired to define the relation of evapotranspiration rate to head between these two elevations. The EVT Package, in contrast, simulates evapotranspiration with a single linear function. The new Drain Return (DRT1) Package can be used to simulate the return flow of water discharged from a drain feature back into the ground-water system. The DRN Package, which has been available in MODFLOW since its initial release, does not have the capability to simulate return of flow. If the return-flow option of the DRT1 Package is selected, for each cell designated as a drain-return cell, the user has the option of specifying a proportion of the water simulated as leaving the ground-water system through the drain feature that is to be simulated as returning simultaneously to one other cell in the model.

  20. Regional gene flow and population structure of the wind-dispersed plant species Hypochaeris radicata (Asteraceae) in an agricultural landscape.

    PubMed

    Mix, C; Arens, P F P; Rengelink, R; Smulders, M J M; Van Groenendael, J M; Ouborg, N J

    2006-06-01

    Using microsatellites, we investigated population structure and gene flow of the short-lived, wind-dispersed plant species Hypochaeris radicata in a fragmented agricultural landscape where more than 99% of the nutrient-poor grasslands have disappeared over the last century. We sampled populations in the few remaining high density populations in conservation areas, as well as individuals that occurred, with lower densities, in linear landscape elements, at two spatial scales. In a re-inventory of the landscape, after 3 years, both extinctions and colonizations of populations were observed. Contrary to expectations, no differences in genetic diversity between high and low density populations were observed. Both types of populations had relatively high levels of diversity. Overall genetic differentiation (theta) was 0.04 and significantly different from zero (P < 0.01). A significant isolation-by-distance pattern was found when all populations were simultaneously analysed (r = 0.24, P = 0.013). Isolation by distance was (marginally) significant at the small scale (r = 0.32, P = 0.06), whereas nonsignificant at the large spatial scale (r = -0.05, P = 0.66). A maximization-of-explained-variance procedure resulted in a threshold distance of 3.5 km above which populations were effectively genetically isolated. An additional partial exclusion Bayesian-based assignment test showed that overall 32.3% of the individuals were assigned to their population of origin, 48% were assigned to another population in the area and 19.7% were not assigned. Together, these results suggest high levels of gene flow. Seed dispersal contributes to the observed gene flow up to several hundred metres, which is higher than previously modelled using aerodynamic models on seed dispersal of H. radicata. We discuss the consequences of these results for an evaluation of the probability of persistence of this species in the fragmented landscape. PMID:16689895

  1. Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions

    USGS Publications Warehouse

    Kalkhoff, S.J.; Lee, K.E.; Porter, S.D.; Terrio, P.J.; Thurman, E.M.

    2003-01-01

    Herbicide concentrations in streams of the U.S. Midwest have been shown to decrease through the growing season due to a variety of chemical and physical factors. The occurrence of herbicide degradation products at the end of the growing season is not well known. This study was conducted to document the occurrence of commonly used herbicides and their degradation products in Illinois, Iowa, and Minnesota streams during base-flow conditions in August 1997. Atrazine, the most frequently detected herbicide (94%), was present at relatively low concentrations (median 0.17 μg L−1). Metolachlor was detected in 59% and cyanazine in 37% of the samples. Seven of nine compounds detected in more than 50% of the samples were degradation products. The total concentration of the degradation products (median of 4.4 μg L−1) was significantly greater than the total concentration of parent compounds (median of 0.26 μg L−1). Atrazine compounds were present less frequently and in significantly smaller concentrations in streams draining watersheds with soils developed on less permeable tills than in watersheds with soils developed on more permeable loess. The detection and concentration of triazine compounds was negatively correlated with antecedent rainfall (April–July). In contrast, acetanalide compounds were positively correlated with antecedant rainfall in late spring and early summer that may transport the acetanalide degradates into ground water and subsequently into nearby streams. The distribution of atrazine degradation products suggests regional differences in atrazine degradation processes.

  2. Five year water and nitrogen balance for a constructed surface flow wetland treating agricultural drainage waters.

    PubMed

    Borin, Maurizio; Tocchetto, Davide

    2007-07-15

    The performance of a constructed surface flow wetland in reducing diffuse N pollution coming from croplands is being investigated in an ongoing experiment, begun in 1998 in NE Italy. The 0.32 ha wetland is vegetated with Phragmites australis (Cav.) Trin. and Typha latifolia (L.). It receives drainage water from 6 ha of land managed for an experiment on drainage systems, where maize, sugarbeet, winter wheat and soybean are cultivated. During the period 1998-2002, the wetland received from 4698 to 8412 mm of water per year (on average, about 9 times the environmental rainfall); its water regimen was discontinuous and flooding occurred on a variable number of days per year (from 13 to 126). Nitric nitrogen was the most important form of element load. Its concentration in the inflow water over time was rather discontinuous, with median values ranging from 0.2 (in 2001) to 4.5 (in 2000) mg L(-1). Inflow nitric N concentrations were occasionally in the 5-15 mg L(-1) range. Concentrations reduced passing through the wetland, with a more evident effect in the last year. Over 5 years, the wetland received slightly more than 2000 kg ha(-1) of nitrogen, 87% in nitric form mostly from farmland drainage. The remaining 13% of N was applied as organic slurry directly onto the wetland, with 5 distributions during 1998 to assess wetland performance in treating occasional organic loads. Field drainage loads had a discontinuous time pattern and occurred mostly during autumn-winter, with the exception of the 2001-2002 season which was a very dry. The wetland discharged 206 kg ha(-1) of N, over the 5-year period, with an apparent removal efficiency of about 90%. The disappearance was mostly due to plant uptake (1110 kg ha(-1)) and soil accumulation (570 kg ha(-1)), with the contribution of denitrification being estimated at around 7%. PMID:17270250

  3. Modelling Water Flow, Heat Transport, Soil Freezing and Thawing, and Snow Processes in a Clayey, Subsurface Drained Agricultural Field

    NASA Astrophysics Data System (ADS)

    Warsta, L.; Turunen, M.; Koivusalo, H. J.; Paasonen-Kivekäs, M.; Karvonen, T.; Taskinen, A.

    2012-12-01

    Simulation of hydrological processes for the purposes of agricultural water management and protection in boreal environment requires description of winter time processes, including heat transport, soil freezing and thawing, and snow accumulation and melt. Finland is located north of the latitude of 60 degrees and has one third to one fourth of the total agricultural land area (2.3 milj. ha) on clay soils (> 30% of clay). Most of the clayey fields are subsurface drained to provide efficient drainage and to enable heavy machines to operate on the fields as soon as possible after the spring snowmelt. Generation of drainflow and surface runoff in cultivated fields leads to nutrient and sediment load, which forms the major share of the total load reaching surface waters at the national level. Water, suspended sediment, and soluble nutrients on clayey field surface are conveyed through the soil profile to the subsurface drains via macropore pathways as the clayey soil matrix is almost impermeable. The objective of the study was to develop the missing winter related processes into the FLUSH model, including soil heat transport, snow pack simulation and the effects of soil freezing and thawing on the soil hydraulic conductivity. FLUSH is an open source (MIT license), distributed, process-based model designed to simulate surface runoff and drainflow in clayey, subsurface drained agricultural fields. 2-D overland flow is described with the diffuse wave approximation of the Saint Venant equations and 3-D subsurface flow with a dual-permeability model. Both macropores and soil matrix are simulated with the Richards equation. Soil heat transport is described with a modified 3-D convection-diffusion equation. Runoff and groundwater data was available from different periods from January 1994 to April 1999 measured in a clayey, subsurface drained field section (3.6 ha) in southern Finland. Soil temperature data was collected in two locations (to a depth of 0.8 m) next to the

  4. Storm flow dynamics and loads of fecal bacteria associated with ponds in southern piedmont and coastal plain watersheds with animal agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Storm events that increase hydrologic flow rates can disturb sediments and produce overland runoff in watersheds with animal agriculture, and, thus, can increase surface water concentrations of fecal bacteria and risk to public health. We tested the hypothesis that strategically placed ponds in wate...

  5. Estimation of long-term Ca(2+) loss through outlet flow from an agricultural watershed and the influencing factors.

    PubMed

    Zhang, Wenzhao; Yin, Chunmei; Chen, Chunlan; Chen, Anlei; Xie, Xiaoli; Fu, Xingan; Hou, Haijun; Wei, Wenxue

    2016-06-01

    Soil Ca(2+) loss from agricultural lands through surface runoff can accelerate soil acidification and render soil degradation, but the characteristics of Ca(2+) loss and influencing factors in watershed scale are unclear. This study was carried out in a watershed with various land uses in a subtropical region of China. The outlet flow was automatically monitored every 5 min all year round, and the water samples were collected twice a year from 2001 to 2011. The concentrations of Ca(2+), Mg(2+), K(+), total nitrogen (TN), and total phosphorus (TP) of water samples were measured. The dynamic losses of the nutrients through the outlet flow were estimated, and the relationships between the nutrient losses and rainfall intensity as well as antecedent soil moisture were investigated. The results showed that great variations of nutrient concentrations and losses appeared during the investigation period. The average concentrations of Ca(2+), Mg(2+), K(+), TN, and TP were 0.43, 0.08, 0.10, 0.19, and 0.003 mmol L(-1), respectively. The average Ca(2+) loss reached 1493.79 mol ha(-1) year(-1) and was several times higher than for Mg(2+), K(+), and TN, about 140 times higher than for TP. Rainfall intensity had remarkable effects on Ca(2+) concentration (P < 0.01) and loss (P < 0.05) when it reached rainstorm level (50 mm day(-1)), while a quadratic relationship was observed between antecedent soil moisture and Ca(2+) concentration only when rainfall intensity was less than 50 mm day(-1). In a word, much greater amounts of Ca(2+) were lost from the watershed, and this may be one important contributor to the increasing acidification of acidic soils in subtropical regions. PMID:26898929

  6. Water flowing north of the border: export agriculture and water politics in a rural community in Baja California.

    PubMed

    Zlolniski, Christian

    2011-01-01

    Favored by neoliberal agrarian policies, the production of fresh crops for international markets has become a common strategy for economic development in Mexico and other Latin American countries. But as some scholars have argued, the global fresh produce industry in developing countries in which fresh crops are produced for consumer markets in affluent nations implies “virtual water flows,” the transfer of high volumes of water embedded in these crops across international borders. This article examines the local effects of the production of fresh produce in the San Quintín Valley in northwestern Mexico for markets in the United States. Although export agriculture has fostered economic growth and employment opportunities for indigenous farm laborers, it has also led to the overexploitation of underground finite water resources, and an alarming decline of the quantity and quality of water available for residents’ domestic use. I discuss how neoliberal water policies have further contributed to water inequalities along class and ethnic lines, the hardships settlers endure to secure access to water for their basic needs, and the political protests and social tensions water scarcity has triggered in the region. Although the production of fresh crops for international markets is promoted by organizations such as the World Bank and Inter-American Development Bank as a model for economic development, I argue that it often produces water insecurity for the poorest, threatening the UN goal of ensuring access to clean water as a universal human right. PMID:22171411

  7. COST-EFFECTIVE STRATEGIES FOR ALLEVIATING WATER QUALITY DEGRADATION FROM IRRIGATED AGRICULTURE

    EPA Science Inventory

    The study moves from a concern for maximizing crop production on a single plot, or farm, to evaluating large-area agricultural systems in order to maximize economic gains under the constraint of minimizing pollution resulting from return flows. To accomplish this objective may re...

  8. Some perspective decisions for the regeneration system equipment of the thermal and nuclear power plants decreasing the probability of water ingress into the turbine and rotor acceleration by return steam flow

    NASA Astrophysics Data System (ADS)

    Trifonov, N. N.; Svyatkin, F. A.; Sintsova, T. G.; Ukhanova, M. G.; Yesin, S. B.; Nikolayenkova, E. K.; Yurchenko, A. Yu.; Grigorieva, E. B.

    2016-03-01

    The regeneration system heaters are one of the sources of possible ingress of the water into the turbine. The water penetrates into the turbine either at the heaters overflow or with the return flow of steam generated when the water being in the heater boils up in the dynamic operation modes or at deenergization of the power-generating unit. The return flow of steam and water is dangerous to the turbine blades and can result in the rotor acceleration. The known protective devices used to prevent the overflow of the low-pressure and high-pressure heaters (LPH and HPH), of the horizontal and vertical heaters of heating-system water (HWH and VWH), as well as of the deaerators and low-pressure mixing heaters (LPMH) were considered. The main protective methods of the steam and water return flows supplied by the heaters in dynamic operation modes or at deenergization of the power-generating unit are described. Previous operating experience shows that the available protections do not fully prevent water ingress into the turbine and the rotor acceleration and, therefore, the development of measures to decrease the possibility of ingress of the water into the turbine is an actual problem. The measures allowing eliminating or reducing the water mass in the heaters are expounded; some of them were designed by the specialists of OAO Polzunov Scientific and Development Association on Research and Design of Power Equipment (NPO CKTI) and are efficiently introduced at heat power plants and nuclear power plants. The suggested technical solutions allow reducing the possibility of the water ingress into the turbine and rotor acceleration by return steam flow in the dynamic operation modes or in the case of power generating unit deenergization. Some of these solutions have been tested in experimental-industrial exploitation and can be used in industry.

  9. Groundwater flow path dynamics and nitrogen transport potential in the riparian zone of an agricultural headwater catchment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stream riparian zones are often thought of as areas that provide natural remediation for groundwater contaminants, especially agricultural nitrogen (N). While denitrification and vegetative uptake tend to be efficient N removal processes in slow moving shallow groundwater, these mechanisms decrease ...

  10. PROCEEDINGS OF NATIONAL CONFERENCE ON IRRIGATION RETURN FLOW QUALITY MANAGEMENT, HELD AT COLORADO STATE UNIVERSITY, FORT COLLINS, COLORADO, ON MAY 16-19, 1977

    EPA Science Inventory

    Research projects and investigations were reported which focused upon defining appropriate technologies for alleviating water quality problems from irrigated agriculture. The emphasis was on better water management practices. Case studies provided insights as to how these technol...

  11. Relative Path Impact Index (RPII): a morphometric approach to quantify the effect of anthropogenic features on surface flow processes in agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Tarolli, P.; Prosdocimi, M.; Sofia, G.; Preti, F.; Dalla Fontana, G.

    2014-12-01

    Soil erosion in cultivated land is one of the main critical issue because of its significant economic consequences, especially whether it occurs in hilly and mountainous environments. Among the cultivated lands, vineyards deserve a particular attention. In fact, they not only represent one of the most important crop in terms of income and employment, but they also constitute the form of agricultural land use that causes the highest soil loss. In these cultivated lands, the construction of terraces is one of the most widely used system for soil and water conservation measures. However, while favoring agricultural activities, terraces may cause local instabilities as well, if they are not properly maintained. Terraced fields are also served by agricultural roads and the construction of these anthropogenic features can have deep effects on water flows and instabilities. In fact, the plane surface of roads can intercept the overland and the subsurface flow and can modify the natural flow directions expanding the drainage network. The main objective of this work is to use high-resolution topography derived from lidar technology for a hydro-geomorphological analysis of terraced vineyards. We considered few case studies located in Italy. At first, the Relative Path Impact Index (RPII) is used to identify likely sections of terraces and agricultural roads subject to potential landsliding or erosion. Statistical thresholds of RPII are then defined to label the most critical areas. Afterwards, using the index and the defined thresholds, different scenarios of soil conservation measures are simulated, to establish the optimal solution for erosion reduction. The results prove the effectiveness of high-resolution topography in the analysis of surface erosion in terraced vineyards, when the surface water flow is the main factor triggering the instabilities. This preliminary analysis can help in scheduling a suitable planning to mitigate the consequences of the anthropogenic

  12. Effect of the submergence, the bed form geometry, and the speed of the surface water flow on the mitigation of pesticides in agricultural ditches

    NASA Astrophysics Data System (ADS)

    Boutron, Olivier; Margoum, Christelle; Chovelon, Jean-Marc; Guillemain, CéLine; Gouy, VéRonique

    2011-08-01

    Pesticides, which have been extensively used in agriculture, have become a major environmental issue, especially regarding surface and groundwater contamination. Of particular importance are vegetated farm drainage ditches, which can play an important role in the mitigation of pesticide contamination by adsorption onto ditch bed substrates. This role is, however, poorly understood, especially regarding the influence of hydrodynamic parameters, which make it difficult to promote best management practice of these systems. We have assessed the influence of three of these parameters (speed of the surface water flow, submergence, and geometrical characteristics of the bed forms) on the transfer and adsorption of selected pesticides (isoproturon, diuron, tebuconazole, and azoxystrobin) into the bed substrate by performing experiments with a tilted experimental flume, using hemp fibers as a standard of natural organic substrates that are found at the bottom of agricultural ditches. Results show the transfer of pesticides from surface water flow into bed substrate is favored, both regarding the amounts transferred into the bed substrate and the kinetics of the transfer, when the surface water speed and the submergence increase and when the bed forms are made of rectangular shapes. Extrapolation of flume data over a distance of several hundred meters suggests that an interesting possibility for improving the mitigation of pesticides in ditches would be to increase the submergence and to favor bed forms that tend to enhance perturbations and subsequent infiltration of the surface water flow.

  13. HYDROGEOLOGIC FOUNDATIONS IN SUPPORT OF ECOSYSTEM RESTORATION: BASE-FLOW LOADINGS OF NITRATE IN MID-ATLANTIC AGRICULTURAL WATERSHEDS

    EPA Science Inventory

    Field evidence suggests that deep denitrification in the subsurface has the potential for
    removal of nitrate from ground water. Two adjacent agricultural watersheds in the mid-
    Atlantic coastal plain display remarkable differences in their ground-water nitrate discharges.

  14. Agriculture Education. Agriculture Structures.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in agriculture structures. The guide presents units of study in the following areas: (1) shop safety, (2) identification and general use of hand tools, (3) power tools, (4) carpentry, (5) blueprint…

  15. Development of Nested, Heterogeneous Ground-Water Flow Models for Study of Transport and Fate of Agricultural Chemicals, Merced County, California

    NASA Astrophysics Data System (ADS)

    Phillips, S. P.; Green, C. T.; Zamora, C.

    2006-05-01

    Multi-scale models of ground-water flow were developed as part of a study of the transport and fate of agricultural chemicals by the National Water-Quality Assessment (NAWQA) Program of the US Geological Survey. Agricultural chemicals of interest included forms of nitrogen and selected pesticides A three- dimensional local-scale model (17 square km) surrounds a well-instrumented, 1-km transect near the Merced River within a principally agricultural land-use setting. This model is nested within a regional-scale model (2,700 square km) of northeastern San Joaquin Valley, California, which provides hydrologically reasonable boundary conditions for the local model. Boundary fluxes were passed from the regional to local model using a hydraulic-conductivity-weighted distribution. The heterogeneity of aquifer materials was incorporated explicitly into the regional and local models. Three-dimensional kriging was used to interpolate sediment texture data from about 3,500 drillers' logs in the regional model area. The resulting distribution of sediment texture was used to estimate hydraulic parameters for each cell in the 16-layer regional model. A subset of these data was used to generate multiple transition-probability-based realizations of hydrofacies distributions for the 110-layer local model. Explicit depiction of heterogeneity in hydraulic conductivity and porosity in the local model incorporates macro-scale hydrodynamic dispersion into the flow model, allowing more direct comparison of particle-tracking results to tracer-derived estimates of ground-water age. Water levels measured in multi-depth wells along the 1-km transect were used to calibrate the local model (median error 0.12 m). Two-dimensional heat-flow models calibrated using continuous multi-depth temperature data from below the bed of the Merced River suggest an annual range of ground-water inflow of about 0-2.4 cm/d for water year 2005. This estimate compares reasonably well to the 4 cm/d simulated in the

  16. Estimates of consumptive use and ground-water return flow and the effect of rising and sustained high river stage on the method of estimation in Cibola Valley, Arizona and California, 1983 and 1984

    USGS Publications Warehouse

    Owen-Joyce, Sandra J.

    1990-01-01

    In Cibola Valley, Arizona, water is pumped from the Colorado River to irrigate crops and to maintain wildlife habitat. Unused water percolates to the water table and, as groundwater, moves downgradient into areas of phreatophytes, into a drainage ditch, out of the flood plain, and back to the river. In 1983 and 1984, groundwater return flow was negligible because in most of Cibola Valley the river lost water to the aquifer. Evapotranspiration was used as an approximation for consumptive use by vegetation. Evapotranspiration was calculated as the sum of the products of the area of vegetation types and water-use rate by vegetation type. Evapotranspiration was estimated to be 70,100 acre-ft in 1983 and 62,600 acre-ft in 1984. These estimates may be in error because of the effect of sustained inundation on the rate of water use by phreatophytes. The effects cannot be quantified and therefore adjustments to rates calculated for dry-surface conditions could not be made. The method of estimating consumptive use of water by vegetation and groundwater return flow is affected by changing conditions during years of rising and sustained high river stage caused by flood-control releases at Parker Dam. Most of the bank storage that will return to the river when the high river stage subsides did not originate as irrigation water. High river stage caused some areas to be flooded directly or raised groundwater levels above the land surface. No crops could be grown in flooded fields. The decreased depth to water and inundation with fresh water resulted in new phreatophyte growth in some areas. In some areas that were flooded, many phreatophytes died. Changes in the inundated and flooded areas throughout the years made it difficult to estimate the evaporation losses from the increased water surface. (USGS)

  17. [Ecological management model of agriculture-pasture ecotone based on the theory of energy and material flow--a case study in Houshan dryland area of Inner Mongolia].

    PubMed

    Fan, Jinlong; Pan, Zhihua; Zhao, Ju; Zheng, Dawei; Tuo, Debao; Zhao, Peiyi

    2004-04-01

    The degradation of ecological environment in the agriculture-pasture ecotone in northern China has been paid more attentions. Based on our many years' research and under the guide of energy and material flow theory, this paper put forward an ecological management model, with a hill as the basic cell and according to the natural, social and economic characters of Houshan dryland farming area inside the north agriculture-pasture ecotone. The input and output of three models, i.e., the traditional along-slope-tillage model, the artificial grassland model and the ecological management model, were observed and recorded in detail in 1999. Energy and material flow analysis based on field test showed that compared with traditional model, ecological management model could increase solar use efficiency by 8.3%, energy output by 8.7%, energy conversion efficiency by 19.4%, N output by 26.5%, N conversion efficiency by 57.1%, P output by 12.1%, P conversion efficiency by 45.0%, and water use efficiency by 17.7%. Among the models, artificial grassland model had the lowest solar use efficiency, energy output and energy conversion efficiency; while the ecological management model had the most outputs and benefits, was the best model with high economic effect, and increased economic benefits by 16.1%, compared with the traditional model. PMID:15334949

  18. Gene flow in the green mirid, Creontiades dilutus (Hemiptera: Miridae), across arid and agricultural environments with different host plant species

    PubMed Central

    Hereward, J P; Walter, G H; DeBarro, P J; Lowe, A J; Riginos, C

    2013-01-01

    Creontiades dilutus (Stål), the green mirid, is a polyphagous herbivorous insect endemic to Australia. Although common in the arid interior of Australia and found on several native host plants that are spatially and temporally ephemeral, green mirids also reach pest levels on several crops in eastern Australia. These host-associated dynamics, distributed across a large geographic area, raise questions as to whether (1) seasonal fluctuations in population size result in genetic bottlenecks and drift, (2) arid and agricultural populations are genetically isolated, and (3) the use of different host plants results in genetic differentiation. We sequenced a mitochondrial COI fragment from individuals collected over 24 years and screened microsatellite variation from 32 populations across two seasons. The predominance of a single COI haplotype and negative Tajima D in samples from 2006/2007 fit with a population expansion model. In the older collections (1983 and 1993), a different haplotype is most prevalent, consistent with successive population contractions and expansions. Microsatellite data indicates recent migration between inland sites and coastal crops and admixture in several populations. Altogether, the data suggest that long-distance dispersal occurs between arid and agricultural regions, and this, together with fluctuations in population size, leads to temporally dynamic patterns of genetic differentiation. Host-associated differentiation is evident between mirids sampled from plants in the genus Cullen (Fabaceae), the primary host, and alternative host plant species growing nearby in arid regions. Our results highlight the importance of jointly assessing natural and agricultural environments in understanding the ecology of pest insects. PMID:23610626

  19. An investigation of used electronics return flows: A data-driven approach to capture and predict consumers storage and utilization behavior

    SciTech Connect

    Sabbaghi, Mostafa; Esmaeilian, Behzad; Raihanian Mashhadi, Ardeshir; Behdad, Sara; Cade, Willie

    2015-02-15

    Highlights: • We analyzed a data set of HDDs returned back to an e-waste collection site. • We studied factors that affect the storage behavior. • Consumer type, brand and size are among factors which affect the storage behavior. • Commercial consumers have stored computers more than household consumers. • Machine learning models were used to predict the storage behavior. - Abstract: Consumers often have a tendency to store their used, old or un-functional electronics for a period of time before they discard them and return them back to the waste stream. This behavior increases the obsolescence rate of used still-functional products leading to lower profitability that could be resulted out of End-of-Use (EOU) treatments such as reuse, upgrade, and refurbishment. These types of behaviors are influenced by several product and consumer-related factors such as consumers’ traits and lifestyles, technology evolution, product design features, product market value, and pro-environmental stimuli. Better understanding of different groups of consumers, their utilization and storage behavior and the connection of these behaviors with product design features helps Original Equipment Manufacturers (OEMs) and recycling and recovery industry to better overcome the challenges resulting from the undesirable storage of used products. This paper aims at providing insightful statistical analysis of Electronic Waste (e-waste) dynamic nature by studying the effects of design characteristics, brand and consumer type on the electronics usage time and end of use time-in-storage. A database consisting of 10,063 Hard Disk Drives (HDD) of used personal computers returned back to a remanufacturing facility located in Chicago, IL, USA during 2011–2013 has been selected as the base for this study. The results show that commercial consumers have stored computers more than household consumers regardless of brand and capacity factors. Moreover, a heterogeneous storage behavior is

  20. Thresholds of flow-induced bed disturbances and their effects on stream metabolism in an agricultural river

    USGS Publications Warehouse

    O'Connor, Ben L.; Harvey, Judson W.; McPhillips, Lauren E.

    2012-01-01

    Storm-driven flow pulses in rivers destroy and restructure sediment habitats that affect stream metabolism. This study examined thresholds of bed disturbances that affected patch- and reach-scale sediment conditions and metabolism rates. A 4 year record of discharge and diel changes in dissolved oxygen concentrations (ΔDO) was analyzed for disturbances and recovery periods of the ΔDO signal. Disturbances to the ΔDO signal were associated with flow pulses, and the recovery times for the ΔDO signal were found to be in two categories: less than 5 days (30% of the disturbances) or greater than 15 days (70% of the disturbances). A field study was performed during the fall of 2007, which included a storm event that increased discharge from 3.1 to 6.9 m3/s over a 7 h period. During stable flow conditions before the storm, variability in patch-scale stream metabolism values were associated with sediment texture classes with values ranging from −16.4 to 2.3 g O22/d (negative sign indicates net respiration) that bounded the reach-averaged rate of −5.6 g O22/d. Hydraulic modeling of bed shear stresses demonstrated a storm-induced flow pulse mobilized approximately 25% of the bed and reach-scale metabolism rates shifted from −5 to −40 g O22/d. These results suggest that storm-induced bed disturbances led to threshold behavior with respect to stream metabolism. Small flow pulses resulted in partial-bed mobilization that disrupted stream metabolism by increased turbidity with short recovery times. Large flow pulses resulted in full-bed mobilization that disrupted stream metabolism by destroying periphyton habitats with long recovery times.

  1. Amazon river flow regime and flood recessional agriculture: Flood stage reversals and risk of annual crop loss

    NASA Astrophysics Data System (ADS)

    Coomes, Oliver T.; Lapointe, Michel; Templeton, Michael; List, Geneva

    2016-08-01

    The annual flood cycle is an important driver of ecosystem structure and function in large tropical rivers such as the Amazon. Riparian peasant communities rely on river fishing and annual floodplain agriculture, closely adapted to the recession phase of the flood pulse. This article reports on a poorly documented but important challenge facing farmers practicing flood recessional agriculture along the Amazon river: frequent, unpredictable stage reversals (repiquetes) which threaten to ruin crops growing on channel bars. We assess the severity of stage reversals for rice production on exposed river mud bars (barreales) near Iquitos, Peru. Crop loss risk is estimated based on a quantitative analysis of 45 years of daily Amazon stage data and field data from floodplain communities nearby in the Muyuy archipelago, upstream of Iquitos. Rice varieties selected, elevations of silt rich bars where rice is sown, as well as planting and harvest dates are analyzed in the light of the timing, frequencies and amplitudes of observed stage reversals that have the potential to destroy growing rice. We find that unpredictable stage reversals can produce substantial crop losses and shorten significantly the length of average growing seasons on lower elevation river bars. The data reveal that local famers extend planting down to lower bar elevations where the mean probabilities of re-submergence before rice maturity (due to reversals) approach 50%, below which they implicitly consider that the risk of crop loss outweighs the potential reward of planting.

  2. An investigation of used electronics return flows: a data-driven approach to capture and predict consumers storage and utilization behavior.

    PubMed

    Sabbaghi, Mostafa; Esmaeilian, Behzad; Raihanian Mashhadi, Ardeshir; Behdad, Sara; Cade, Willie

    2015-02-01

    Consumers often have a tendency to store their used, old or un-functional electronics for a period of time before they discard them and return them back to the waste stream. This behavior increases the obsolescence rate of used still-functional products leading to lower profitability that could be resulted out of End-of-Use (EOU) treatments such as reuse, upgrade, and refurbishment. These types of behaviors are influenced by several product and consumer-related factors such as consumers' traits and lifestyles, technology evolution, product design features, product market value, and pro-environmental stimuli. Better understanding of different groups of consumers, their utilization and storage behavior and the connection of these behaviors with product design features helps Original Equipment Manufacturers (OEMs) and recycling and recovery industry to better overcome the challenges resulting from the undesirable storage of used products. This paper aims at providing insightful statistical analysis of Electronic Waste (e-waste) dynamic nature by studying the effects of design characteristics, brand and consumer type on the electronics usage time and end of use time-in-storage. A database consisting of 10,063 Hard Disk Drives (HDD) of used personal computers returned back to a remanufacturing facility located in Chicago, IL, USA during 2011-2013 has been selected as the base for this study. The results show that commercial consumers have stored computers more than household consumers regardless of brand and capacity factors. Moreover, a heterogeneous storage behavior is observed for different brands of HDDs regardless of capacity and consumer type factors. Finally, the storage behavior trends are projected for short-time forecasting and the storage times are precisely predicted by applying machine learning methods. PMID:25534039

  3. Dynamics of stream nitrate sources and flow pathways during storm flows on urban, forest, and agricultural watersheds in central PA, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potential sources and flow paths of stream water nitrate were assessed using stable isotopes in nitrate (delta 15N-NO3 and delta 18O-NO3) and water (delta 18O-H2O) in Spring Creek, a 201 square-kilometer mixed land-use watershed located in central Pennsylvania. Six storm events were sampled during ...

  4. Why Do Staff Return?

    ERIC Educational Resources Information Center

    Magnuson, Connie

    1992-01-01

    Surveyed 211 returning staff from 25 camps and interviewed 19 returning staff to study factors that influence a counselor's decision to return to camp. Examined the following dimensions of motivation and hygiene factors: (1) stimulation or inspiration; (2) personal; (3) job-related experience; (4) living conditions and camp life; (5) camp…

  5. Finding Multiple Internal Rates of Return for a Project with Non-Conventional Cash Flows: Utilizing Popular Financial/Graphing Calculators and Spreadsheet Software

    ERIC Educational Resources Information Center

    Chen, Jeng-Hong

    2008-01-01

    This study demonstrates that a popular graphing calculator among students, TI-83 Plus, has a powerful function to draw the NPV profile and find the accurate multiple IRRs for a project with non-conventional cash flows. However, finance textbooks or related supplementary materials do not provide students instructions for this part. The detailed…

  6. 26 CFR 301.6103(j)(5)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... returns to officers and employees of the Department of Agriculture for conducting the census of agriculture. 301.6103(j)(5)-1 Section 301.6103(j)(5)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... officers and employees of the Department of Agriculture for conducting the census of agriculture....

  7. 26 CFR 301.6103(j)(5)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... returns to officers and employees of the Department of Agriculture for conducting the census of agriculture. 301.6103(j)(5)-1 Section 301.6103(j)(5)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... officers and employees of the Department of Agriculture for conducting the census of agriculture....

  8. 26 CFR 301.6103(j)(5)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... returns to officers and employees of the Department of Agriculture for conducting the census of agriculture. 301.6103(j)(5)-1 Section 301.6103(j)(5)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... officers and employees of the Department of Agriculture for conducting the census of agriculture....

  9. 26 CFR 301.6103(j)(5)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... returns to officers and employees of the Department of Agriculture for conducting the census of agriculture. 301.6103(j)(5)-1 Section 301.6103(j)(5)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... officers and employees of the Department of Agriculture for conducting the census of agriculture....

  10. 26 CFR 301.6103(j)(5)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... returns to officers and employees of the Department of Agriculture for conducting the census of agriculture. 301.6103(j)(5)-1 Section 301.6103(j)(5)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... officers and employees of the Department of Agriculture for conducting the census of agriculture....

  11. Cost-Effectiveness Analysis of Surface Flow Constructed Wetlands (SFCW) for Nutrient Reduction in Drainage Discharge from Agricultural Fields in Denmark

    NASA Astrophysics Data System (ADS)

    Gachango, F. G.; Pedersen, S. M.; Kjaergaard, C.

    2015-12-01

    Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW could be a better optimal nutrients reduction measure in drainage catchments characterized with higher nutrient loads.

  12. Developing an Integrated Understanding of the Relationship Between Urban Wastewater Flows and Downstream Reuse in Irrigated Agriculture: A Global Perspective

    NASA Astrophysics Data System (ADS)

    Thebo, A.; Nelson, K.; Drechsel, P.; Lambin, E.

    2015-12-01

    Globally, less than ten percent of collected wastewater receives any form of treatment. This untreated wastewater is discharged to surface waters where it is diluted and reused by farmers and municipalities downstream. Without proper safeguards, the use of these waters can present health risks. However, these same waters also provide a reliable and nutrient rich water source for farmers, often in regions where water is already physically or economically scarce. Case studies show the prevalence and diversity of motivations for indirect reuse, but are difficult to interpret in aggregate at the global scale. This study quantifies the global extent and characteristics of the reuse of wastewater in irrigated agriculture through three main components: Quantifying the global extent of urban and peri-urban irrigated and rainfed croplands; Evaluating the contribution of urban wastewater production to available blue water at the catchment scale; Developing an irrigation water quality indicator and classifying irrigated croplands downstream of cities on the basis of this indicator. Each of these components integrates several global scale spatial datasets including MIRCA2000 (irrigated croplands); GDBD (stream channels and catchments); and compilations of water use, sewerage and wastewater treatment data. All analyses were conducted using spatial analysis tools in ArcGIS and Python. This analysis found that 60 percent of all irrigated croplands (130 Mha) were within 20 km of cities. Urban irrigated croplands were found to be farmed with greater cropping intensity (1.48) as compared to non-urban irrigated croplands. Ten percent of the global catchment area is in catchments where domestic wastewater constitutes greater than five percent of available blue water. In contrast, 25 percent of irrigated croplands are located in catchments where domestic wastewater exceeds five percent of available blue water. Particularly in the water scarce regions of North Africa and East Asia, a

  13. Nitrate pollution from agriculture in different hydrogeological zones of the regional groundwater flow system in the North China Plain

    NASA Astrophysics Data System (ADS)

    Chen, Jianyao; Tang, Changyuan; Sakura, Yasuo; Yu, Jingjie; Fukushima, Yoshihiro

    2005-06-01

    A survey of the quality of groundwater across a broad area of the North China Plain, undertaken in 1998 to 2000, indicates that nitrate pollution is a serious problem affecting the drinking water for a vast population. The use of nitrogen (N)-fertilizer in agriculture has greatly increased over the past 20 years to meet the food needs of the rapidly expanding population. During the study, 295 water samples were collected from wells and springs to determine the water chemistry and the extent of nitrate pollution. High concentrations of nitrate, especially in a recharge area along the western side, but also in the vicinity of Beijing and locally in other parts of the plain, pose a serious problem for the drinking water supply. In places, the nitrate concentration exceeds the maximum for safe drinking water of 45 mg/L. The intense use of N-fertilizer and the widespread use of untreated groundwater for crop irrigation contribute greatly to the problem, but no doubt the disposal of industrial and municipal waste into streams and infiltrating the aquifer also contribute to the problem; however, the lack of data prevents evaluation of those sources. In the recharge area, nitrate is found at depths of as much as 50 m. Near Beijing, relatively high concentrations of nitrate occur at depths of as much as 80 m. In the discharge area, in the vicinity of the Yellow River, high concentrations of nitrate occur at depths of <8 m.

  14. Detecting transition in agricultural systems

    NASA Technical Reports Server (NTRS)

    Neary, P. J.; Coiner, J. C.

    1979-01-01

    Remote sensing of agricultural phenomena has been largely concentrated on analysis of agriculture at the field level. Concern has been to identify crop status, crop condition, and crop distribution, all of which are spatially analyzed on a field-by-field basis. A more general level of abstraction is the agricultural system, or the complex of crops and other land cover that differentiate various agricultural economies. The paper reports on a methodology to assist in the analysis of the landscape elements of agricultural systems with Landsat digital data. The methodology involves tracing periods of photosynthetic activity for a fixed area. Change from one agricultural system to another is detected through shifts in the intensity and periodicity of photosynthetic activity as recorded in the radiometric return to Landsat. The Landsat-derived radiometric indicator of photosynthetic activity appears to provide the ability to differentiate agricultural systems from each other as well as from conterminous natural vegetation.

  15. Return flux experiment

    NASA Technical Reports Server (NTRS)

    Tveekrem, June L.

    1992-01-01

    All spacecraft emit molecules via outgassing, thruster plumes, vents, etc. The return flux is the portion of those molecules that scatter from the ambient atmosphere and return to the spacecraft. Return flux allows critical spacecraft surfaces to become contaminated even when there is no direct line of sight between the contamination source and the critical surface. Data from the Long Duration Exposure Facility (LDEF) show that contamination of LDEF surfaces could not have come entirely from direct flux. The data suggest significant return flux. Several computer models have been developed to simulate return flux, but the predictions have never been verified in orbit. Large uncertainties in predictions lead to overly conservative spacecraft designs. The purpose of the REturn FLux EXperiment (REFLEX) is to fly a controlled experiment that can be directly compared with predictions from several models.

  16. Assured crew return vehicle

    NASA Technical Reports Server (NTRS)

    Cerimele, Christopher J. (Inventor); Ried, Robert C. (Inventor); Peterson, Wayne L. (Inventor); Zupp, George A., Jr. (Inventor); Stagnaro, Michael J. (Inventor); Ross, Brian P. (Inventor)

    1991-01-01

    A return vehicle is disclosed for use in returning a crew to Earth from low earth orbit in a safe and relatively cost effective manner. The return vehicle comprises a cylindrically-shaped crew compartment attached to the large diameter of a conical heat shield having a spherically rounded nose. On-board inertial navigation and cold gas control systems are used together with a de-orbit propulsion system to effect a landing near a preferred site on the surface of the Earth. State vectors and attitude data are loaded from the attached orbiting craft just prior to separation of the return vehicle.

  17. Production of carbonaceous adsorbents from agricultural by-products and novolac resin under a continuous countercurrent flow type pyrolysis operation.

    PubMed

    Ioannou, Z; Simitzis, J

    2013-02-01

    Carbonaceous adsorbents based on novolac resin (N) and olive stone biomass (B) in a proportion of 20/80 and 40/60 w./w. N/O were produced. The specimens were cured (c) and pyrolyzed/carbonized (C) up to 1000 °C under a continuous countercurrent flow type pyrolysis operation (N20B-cC, N40B-cC). Commercial activated carbon (AC) was used for comparison reasons. Methylene blue adsorption from its aqueous solutions onto the adsorbents and kinetic analysis were investigated. The specific surface area of adsorbents and the gross calorific values (GCV) of cured materials were determined. The results show that N40B-cC presents lower weight loss and shrinkage but higher methylene blue adsorption than N20B-cC. Pseudo-second order mechanism describes better methylene blue adsorption onto all adsorbents. The specific surface area of carbonaceous and the gross calorific values of cured materials follow the order: AC>N20B-cC>N40B-cC and N100-c>N40B-c>N20B-c>B respectively. Olive stone biomass may constitute a suitable precursor for the production of carbonaceous materials. PMID:23246760

  18. Farming with Grass: Achieving Sustainable Mixed Agricultural Landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Grassla...

  19. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 4 2012-01-01 2012-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  20. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  1. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  2. 7 CFR 273.32 - Households who return to TANF during the transitional period.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Households who return to TANF during the transitional period. 273.32 Section 273.32 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION...

  3. Martian base agriculture: The effect of low gravity on water flow, nutrient cycles, and microbial biomass dynamics

    NASA Astrophysics Data System (ADS)

    Maggi, Federico; Pallud, Céline

    2010-11-01

    The latest advances in bioregenerative strategies for long-term life support in extraterrestrial outposts such as on Mars have indicated soil-based cropping as an effective approach for waste decomposition, carbon sequestration, oxygen production, and water biofiltration as compared to hydroponics and aeroponics cropping. However, it is still unknown if cropping using soil systems could be sustainable in a Martian greenhouse under a gravity of 0.38 g. The most challenging aspects are linked to the gravity-induced soil water flow; because water is crucial in driving nutrient and oxygen transport in both liquid and gaseous phases, a gravitational acceleration lower than g = 9.806 m s -2 could lead to suffocation of microorganisms and roots, with concomitant emissions of toxic gases. The effect of Martian gravity on soil processes was investigated using a highly mechanistic model previously tested for terrestrial crops that couples soil hydraulics and nutrient biogeochemistry. Net leaching of NO3- solute, gaseous fluxes of NH 3, CO 2, N 2O, NO and N 2, depth concentrations of O 2, CO 2 and dissolved organic carbon (DOC), and pH in the root zone were calculated for a bioregenerative cropping unit under gravitational acceleration of Earth and for its homologous on Mars, but under 0.38 g. The two cropping units were treated with the same fertilizer type and rate, and with the same irrigation regime, but under different initial soil moisture content. Martian gravity reduced water and solute leaching by about 90% compared to Earth. This higher water holding capacity in soil under Martian gravity led to moisture content and nutrient concentrations that favoured the metabolism of various microbial functional groups, whose density increased by 5-10% on Mars as compared to Earth. Denitrification rates became substantially more important than on Earth and ultimately resulted in 60%, 200% and 1200% higher emissions of NO, N 2O and N 2 gases, respectively. Similarly, O 2 and DOC

  4. In science communication, why does the idea of a public deficit always return? How do the shifting information flows in healthcare affect the deficit model of science communication?

    PubMed

    Ko, Henry

    2016-05-01

    The healthcare field contains a multitude of opportunities for science communication. Given the many stakeholders dancing together in a multidirectional tango of communication, we need to ask how much does the deficit model apply to the health field? History dictates that healthcare professionals are the holders of all knowledge, and the patients and other stakeholders are the ones that need the scientific information communicated to them. This essay argues otherwise, in part due to the rise of shared decision-making and patients and other stakeholders acting as partners in healthcare. The traditional deficit model in health held that: (1) doctors were experts and patients were consumers, (2) it is impossible for the public to grasp the many disciplines of knowledge in medicine, (3) if experts have trouble keeping up with medical research then the public surely can't keep up, and (4) it is safer for healthcare professionals to communicate to the public using a deficit model. However, with the rise of partnerships with patients in healthcare decision-making, the deficit model might be weakening. Examples of public participation in healthcare decision-making include: (1) crowd-sourcing public participation in systematic reviews, (2) public participation in health policy, (3) public collaboration in health research, and (4) health consumer groups acting as producers of health information. With the challenges to the deficit model in science communication in health, caution is needed with the increasing role of technology and social media, and how these may affect the legitimacy of healthcare information flows away from the healthcare professional. PMID:27117770

  5. A Comparison of Methods for Estimating Evapotranspiration (ET) in a Semi-Arid Agricultural System

    NASA Astrophysics Data System (ADS)

    Gordon, B. L.; Claes, N.; Miller, S. N.; Paige, G. B.; Parsekian, A.; Beverly, D.

    2015-12-01

    In the intermountain West, much like the rest of the world, agriculture is the oldest and largest water consumer. Particularly in the arid headwaters states of the intermountain west changing water demands are highlighting the importance of water use efficiency in agriculture. In flood irrigation an area is irrigated until saturation is achieved although crops only consume a portion of the total water applied. The remaining water eventually returns to streams or aquifers. Accurately quantifying the portion of applied water that is consumptively used—and its corollary in the form of return flows—represents an important avenue for potential water use reduction in the face of increasing demands from sundry downstream users. Consumptive use has historically been understood as the difference between the irrigation water applied and irrigation water returned to adjacent surface waters via quick or delayed return flow as well as overland flow. Penman-derived models, which calculate evapotranspiration based on meteorological data, are another widely recognized method for estimating consumptive use. We determined consumptive use on an agricultural field in northeastern Wyoming using both of these two traditional methods as well as a quantitative scintillometer-based estimate, which couples meteorological data with the latent heat flux across a field to measure evapotranspiration for a given area. Since the wider application of the scintillometer is limited by the instrument's complexity and cost, a comparison of the resulting data with these two more customary methods provides critical insight in to where certain methods might under or overestimate consumptive use. The purpose of this comparison is twofold. First, the comparison of these three methods allows for the optimization of a reach-scale water budget that aims to better characterize and quantify return flow processes. Second, the addition of information that couples hydrology, meteorology, geophysics, and heat

  6. Surge Driven Return Flow Results in Deposition of Coarse Grain Horizons Archiving a 4000 Year Record of Extreme Storm Events, Cape Cod, Massachusetts

    NASA Astrophysics Data System (ADS)

    Maio, C. V.; Donnelly, J. P.; Sullivan, R.; Weidman, C. R.; Sheremet, V.

    2014-12-01

    The brevity of the instrumental record and lack of detailed historical accounts is a limiting factor in our understanding of the relationship between climate change and the frequency and intensity of extreme storm events. This study applied paleotempestologic and hydrographic methods to identify the mechanisms of storm-induced coarse grain deposition and reconstruct a late Holocene storm record within Waquoit Bay, Massachusetts. Three sediment cores (6.0 m, 8.4 m, and 8.2 m) were collected in 3 m of water using a vibracore system. Grain sizes were measured along core to identify coarse grain anomalies that serve as a proxy for past storm events. An historical age model (1620-2011 AD) was developed based on Pb pollution chronomarkers derived from X-Ray Florescence bulk Pb data, equating to a sedimentation rate of 8-8.3 mm/yr (R2 = 0.99). A long-term (4000 to 275 years before present) sedimentation rate of 1.1-1.4 mm/yr (R2 = 0.89) was calculated based on twenty-four continuous flow atomic mass spectrometry 14C ages of marine bivalves. To determine hydrographic conditions within the embayment during storm events current meters and tide gauges were deployed during Hurricane Irene (2011) which measured a storm surge of 88 cm above mean sea level. The buildup of storm water against the landward shoreline resulted in a measured 10 cm/s seaward moving bottom current capable of transporting coarse sand eroded from the adjacent shoreface into the coring site. Modeled surges for eleven modern and historic storm events ranged in height from 0.37 m (2011) to 3.72 m (1635) above mean high water. The WAQ1, WAQ2, and WAQ3 cores recorded a total of 89, 139, and 137 positive anomalies that exceeded the lower threshold and 15, 34, and 12 that exceeded the upper threshold respectively. Events recorded during the historic period coincide with documented storm events. The mean frequency within the three cores applying the lower threshold was 2.6 events per century, while applying the

  7. News Particle Physics: ATLAS unveils mural at CERN Prize: Corti Trust invites essay entries Astrophysics: CERN holds cosmic-ray conference Researchers in Residence: Lord Winston returns to school Music: ATLAS scientists record physics music Conference: Champagne flows at Reims event Competition: Students triumph at physics olympiad Teaching: Physics proves popular in Japanese schools Forthcoming Events

    NASA Astrophysics Data System (ADS)

    2011-01-01

    Particle Physics: ATLAS unveils mural at CERN Prize: Corti Trust invites essay entries Astrophysics: CERN holds cosmic-ray conference Researchers in Residence: Lord Winston returns to school Music: ATLAS scientists record physics music Conference: Champagne flows at Reims event Competition: Students triumph at physics olympiad Teaching: Physics proves popular in Japanese schools Forthcoming Events

  8. A Profile of Southern Agriculture Students. Journal Series No. 1-810032 of the Alabama Agricultural Experiment Station.

    ERIC Educational Resources Information Center

    Dunkelberger, John E.; And Others

    Questionnaires which focused on attributes of undergraduate agriculture students and their reasons for enrolling in agriculture were returned by 3,182 students attending land-grant universities in the South, and a profile of Southern agriculture students evolved. During the 1970's, more women and fewer Blacks enrolled in agricultural curricula.…

  9. The seasonal dynamics of the stream sources and input flow paths of water and nitrogen of an Austrian headwater agricultural catchment.

    PubMed

    Exner-Kittridge, Michael; Strauss, Peter; Blöschl, Günter; Eder, Alexander; Saracevic, Ernis; Zessner, Matthias

    2016-01-15

    Our study examines the source aquifers and stream inputs of the seasonal water and nitrogen dynamics of a headwater agricultural catchment to determine the dominant driving forces for the seasonal dynamics in the surface water nitrogen loads and concentrations. We found that the alternating aquifer contributions throughout the year of the deep and shallow aquifers were the main cause for the seasonality of the nitrate concentration. The deep aquifer water typically contributed 75% of the total outlet discharge in the summer and 50% in the winter when the shallow aquifer recharges due to low crop evapotranspiration. The shallow aquifer supplied the vast majority of the nitrogen load to the stream due to the significantly higher total nitrogen concentration (11 mg-N/l) compared to the deep aquifer (0.50 mg-N/l). The main stream input pathway for the shallow aquifer nitrogen load was from the perennial tile drainages providing 60% of the total load to the stream outlet, while only providing 26% of the total flow volume. The diffuse groundwater input to the stream was the largest input to the stream (39%), but only supplied 27% to the total nitrogen load as the diffuse water was mostly composed of deep aquifer water. PMID:26562340

  10. Development of multianalyte flow-through and lateral-flow assays using gold particles and horseradish peroxidase as tracers for the rapid determination of carbaryl and endosulfan in agricultural products.

    PubMed

    Zhang, Can; Zhang, Yan; Wang, Shuo

    2006-04-01

    Membrane-based competitive immunoassays using gold particles and horseradish peroxidase (HRP) as tracers in flow-through and lateral-flow formats for multianalysis of carbaryl and endosulfan were developed. For gold-based immunoassay, membrane strips were coated with goat anti-rabbit IgG (control line) and carbaryl hapten-ovalbumin (OVA) and endosulfan hapten-OVA (test lines). The visual detection limits for carbaryl and endosulfan were 100 and 10 microg/L in gold-based assays, respectively. For immunoassay using HRP as tracer, anti-carbaryl and anti-endosulfan antibodies were separately coated on the membrane as test lines, and the visual detection limits were 10 microg/L for carbaryl and 1 microg/L for endosulfan. The developed assays used gold particles and HRP as labels, respectively; 10 times enhancement in the visual detection limit using HRP label was obtained in the study. Matrix interference was eliminated by appropriate dilution of sample extracts with buffer. For the validation of the multianalyte assay, the samples were screened by multianalyte gold-based assay and confirmed by HPLC for carbaryl determination and by GC for endosulfan determination. The results of multianalyte gold-based flow-through assay for the determination of carbaryl and endosulfan were in good agreement with the results of instrumental analysis (HPLC with ultraviolet detection and GC with electron capture detection). The developed multianalyte immunoassays for which the results were interpreted visually can be used as convenient qualitative tools for on-site rapid screening of carbaryl and endosulfan simultaneously in agricultural products. PMID:16569035

  11. Lightning return stroke models

    NASA Technical Reports Server (NTRS)

    Lin, Y. T.; Uman, M. A.; Standler, R. B.

    1980-01-01

    We test the two most commonly used lightning return stroke models, Bruce-Golde and transmission line, against subsequent stroke electric and magnetic field wave forms measured simultaneously at near and distant stations and show that these models are inadequate to describe the experimental data. We then propose a new return stroke model that is physically plausible and that yields good approximations to the measured two-station fields. Using the new model, we derive return stroke charge and current statistics for about 100 subsequent strokes.

  12. Agricultural Production.

    ERIC Educational Resources Information Center

    Lehigh County Area Vocational-Technical School, Schnecksville, PA.

    This brochure describes the philosophy and scope of a secondary-level course in agricultural production. Addressed in the individual units of the course are the following topics: careers in agriculture and agribusiness, animal science and livestock production, agronomy, agricultural mechanics, supervised occupational experience programs, and the…

  13. 7 CFR 46.21 - Returns, rejections, or credit memorandums on sales.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Returns, rejections, or credit memorandums on sales... COMMODITIES ACT, 1930 Records of Market Receivers § 46.21 Returns, rejections, or credit memorandums on sales. In the event of the rejection and return of any produce sold for or on behalf of another,...

  14. 7 CFR 46.21 - Returns, rejections, or credit memorandums on sales.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Returns, rejections, or credit memorandums on sales... COMMODITIES ACT, 1930 Records of Market Receivers § 46.21 Returns, rejections, or credit memorandums on sales. In the event of the rejection and return of any produce sold for or on behalf of another,...

  15. 7 CFR 46.21 - Returns, rejections, or credit memorandums on sales.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Returns, rejections, or credit memorandums on sales... COMMODITIES ACT, 1930 Records of Market Receivers § 46.21 Returns, rejections, or credit memorandums on sales. In the event of the rejection and return of any produce sold for or on behalf of another,...

  16. 7 CFR 46.21 - Returns, rejections, or credit memorandums on sales.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Returns, rejections, or credit memorandums on sales... COMMODITIES ACT, 1930 Records of Market Receivers § 46.21 Returns, rejections, or credit memorandums on sales. In the event of the rejection and return of any produce sold for or on behalf of another,...

  17. 43 CFR 3872.3 - Presumption as to land returned as mineral.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Presumption as to land returned as mineral... CONFLICTS Protests, Contests and Conflicts § 3872.3 Presumption as to land returned as mineral. Public land returned upon the survey records as mineral shall be withheld from entry as agricultural land until...

  18. 43 CFR 3872.3 - Presumption as to land returned as mineral.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Presumption as to land returned as mineral... CONFLICTS Protests, Contests and Conflicts § 3872.3 Presumption as to land returned as mineral. Public land returned upon the survey records as mineral shall be withheld from entry as agricultural land until...

  19. 43 CFR 3872.3 - Presumption as to land returned as mineral.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Presumption as to land returned as mineral... CONFLICTS Protests, Contests and Conflicts § 3872.3 Presumption as to land returned as mineral. Public land returned upon the survey records as mineral shall be withheld from entry as agricultural land until...

  20. 43 CFR 3872.3 - Presumption as to land returned as mineral.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Presumption as to land returned as mineral... CONFLICTS Protests, Contests and Conflicts § 3872.3 Presumption as to land returned as mineral. Public land returned upon the survey records as mineral shall be withheld from entry as agricultural land until...

  1. Enhancement of the southward return flow of the Atlantic Meridional Overturning Circulation by data assimilation and its influence in an assimilative ocean simulation forced by CORE-II atmospheric forcing

    NASA Astrophysics Data System (ADS)

    Fujii, Yosuke; Tsujino, Hiroyuki; Toyoda, Takahiro; Nakano, Hideyuki

    2015-08-01

    This paper examines the difference in the Atlantic Meridional Overturning Circulation (AMOC) mean state between free and assimilative simulations of a common ocean model using a common interannual atmospheric forcing. In the assimilative simulation, the reproduction of cold cores in the Nordic Seas, which is absent in the free simulation, enhances the overflow to the North Atlantic and improves AMOC with enhanced transport of the deeper part of the southward return flow. This improvement also induces an enhanced supply of North Atlantic Deep Water (NADW) and causes better representation of the Atlantic deep layer despite the fact that correction by the data assimilation is applied only to temperature and salinity above a depth of 1750 m. It also affects Circumpolar Deep Water in the Southern Ocean. Although the earliest influence of the improvement propagated by coastal waves reaches the Southern Ocean in 10-15 years, substantial influence associated with the arrival of the renewed NADW propagates across the Atlantic Basin in several decades. Although the result demonstrates that data assimilation is able to improve the deep ocean state even if there is no data there, it also indicates that long-term integration is required to reproduce variability in the deep ocean originating from variations in the upper ocean. This study thus provides insights on the reliability of AMOC and the ocean state in the Atlantic deep layer reproduced by data assimilation systems.

  2. Return to Bangka Island.

    PubMed

    Spence, J

    2001-07-01

    This article is a return in a couple of ways to one of the most tragic events in the history of Australian military nursing. Firstly, it describes how the evacuation of nurses from Singapore in 1941 led to circumstances that resulted in the massacre or internment of many of those women. Then in 1993, a group of surviving World War II nurses and current serving Australian Army nurses returned to the site of their sorrow. PMID:15129536

  3. Agricultural Waste.

    PubMed

    Xue, Ling; Zhang, Panpan; Shu, Huajie; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2016-10-01

    In recent years, the quantity of agricultural waste has been rising rapidly all over the world. As a result, the environmental problems and negative impacts of agricultural waste are drawn more and more attention. Therefore, there is a need to adopt proper approaches to reduce and reuse agricultural waste. This review presented about 200 literatures published in 2015 relating to the topic of agricultural waste. The review examined research on agricultural waste in 2015 from the following four aspects: the characterization, reuse, treatment, and management. Researchers highlighted the importance to reuse agricultural waste and investigated the potential to utilize it as biofertilizers, cultivation material, soil amendments, adsorbent, material, energy recycling, enzyme and catalyst etc. The treatment of agricultural waste included carbonization, biodegradation, composting hydrolysis and pyrolysis. Moreover, this review analyzed the differences of the research progress in 2015 from 2014. It may help to reveal the new findings and new trends in this field in 2015 comparing to 2014. PMID:27620093

  4. Vocational Agriculture Education. Agricultural Mechanics.

    ERIC Educational Resources Information Center

    Smith, Eddie; And Others

    To assist teachers in agricultural mechanics in providing comprehensive instruction to their students, this curriculum guide treats both the mechanical skills and knowlege necessary for this specialized area. Six sections are included, as follow: orientation and safety; agricultural mechanics skills; agricultural power and machinery; agricultural…

  5. Quality of returns: Is it a factor in remanufacturing?

    NASA Astrophysics Data System (ADS)

    Behret, Hülya; Korugan, Aybek

    2005-11-01

    The return flow of remanufacturing processes is highly variable in terms of the quality of returned products. This fact causes higher variability in remanufacturing processing times. In order to decrease the variability in the process the returns can be inspected and classified according to their quality following their arrival. However this classification will add an extra cost to the remanufacturing process. In this study we investigate the pros and cons of such a classification.

  6. Agriculture, summary

    NASA Technical Reports Server (NTRS)

    Baldwin, R.

    1975-01-01

    Applications of remotely sensed data in agriculture are enumerated. These include: predictions of forage for range animal consumption, forest management, soil mapping, and crop inventory and management.

  7. Estimations of the maximum tangential velocity V θm in the vortex core region and also the mean rotational velocity V oi near the concave wall surface in the returned flow type cyclone dust collector

    NASA Astrophysics Data System (ADS)

    Ogawa, Akira

    2010-12-01

    There are many types of cyclone dust collectors for separating the fine solid and dust particles from gases in the various industries and also in the home used purposes. For estimating the power loss and the collection efficiency, one of the most important factors is the maximum tangential velocity V θm in the vortex core region in the cyclone body. In order to determine V θm by the simple method, it is useful to apply the mechanical balance of the angular momentum fluxes under the assumption of Ogawa combined vortex model which is composed of the quasi-forced vortex in the vortex core region and also the quasi-free vortex surrounded the vortex core region and also under the assumption of the introduction of equivalent length Heq corresponding to the cone spaces of the cyclone body and the dust bunker. On the other hand, the mean rotational velocity V oi near the concave wall surface is also estimated by the mechanical balance of angular momentum fluxes with the moment of viscous friction force. For confirming the general applications of the obtained equations, the returned flow types cyclones changed the throat diameter D3 are designed. The material of the cyclone is the transparent acrylic resin. Therefore the inner surface of the cyclone body can be regarded as smooth surface. The comparisons of the measured velocities V θm and V oi by a cylindrical Pitot tube are shown in good agreement with those of the proposed equations. The above stated results are described in detail.

  8. [Fever in returning travelers].

    PubMed

    Burchard, G

    2014-03-01

    Travel-related illness is most often due to gastrointestinal, febrile, and dermatologic diseases. Fever in a returned traveler demands prompt attention because it may be a manifestation of an infection that could be rapidly progressive and lethal. The approach to the febrile patient should be stepwise and consider travel and exposure history. Malaria is the most common cause of fever in patients returning from Sub-Saharan Africa, whereas dengue is more frequent in travelers from other tropical and subtropical areas. Other serious diseases are typhoid and paratyphoid fever, amebic liver abscess, visceral leishmaniasis, leptospirosis and-rarely-viral hemorrhagic fevers. PMID:24557143

  9. Electrostatic Return of Contaminants

    NASA Technical Reports Server (NTRS)

    Rantanen, R.; Gordon, T.

    2003-01-01

    A Model has been developed capable of calculating the electrostatic return of spacecraft-emitted molecules that are ionized and attracted back to the spacecraft by the spacecraft electric potential on its surfaces. The return of ionized contaminant molecules to charged spacecraft surfaces is very important to all altitudes. It is especially important at geosynchronous and interplanetary environments, since it may be the only mechanism by which contaminants can degrade a surface. This model is applicable to all altitudes and spacecraft geometries. In addition to results of the model will be completed to cover a wide range of potential space systems.

  10. Agricultural Wastes.

    ERIC Educational Resources Information Center

    Jewell, W. J.; Switzenbaum, M. S.

    1978-01-01

    Presents a literature review of agricultural wastes, covering publications of 1976-77. Some of the areas covered are: (1) water characteristics and impacts; (2) waste treatment; (3) reuse of agricultural wastes; and (4) nonpoint pollution sources. A list of 150 references is also presented. (HM)

  11. VOCATIONAL AGRICULTURE.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Research Coordinating Unit.

    TO ASSIST THOSE WHO MAKE DECISIONS RELATING TO EDUCATIONAL PROGRAMS IN AGRICULTURE, RECENT RESEARCH IN VOCATIONAL AGRICULTURE IS SUMMARIZED. A 1963 STUDY TREATS THE RELATIONSHIP BETWEEN WORK EXPERIENCE AND STUDENT CHARACTERISTICS, PLANS, AND ASPIRATIONS. STUDIES ON POST-SECONDARY EDUCATION CONCERN GUIDELINES FOR TECHNICIAN PROGRAMS, JUSTIFICATION…

  12. The effects of agriculture on the volcanic aquifers of the canary islands

    NASA Astrophysics Data System (ADS)

    Custodio, E.; Guerra, J. A.; Jiménez, J.; Medina, J. A.; Soler, C.

    1983-12-01

    Agriculture is a basic economic activity in the Canary Islands, a Spanish region in the Atlantic Ocean, facing the Sahara. The main crops are bananas, tomatoes, and other special ones suitable for exportation. Fertilizers are applied in high quantities on the scarce land available. The relatively good vertical permeability of the soils favors the deep infiltration of irrigation return flows. Water is obtained by an extraordinary net of shaft wells and water galleries, supplemented when possible by surface reservoirs in the deep gullies. Water is distributed by an extensive network of pipes and canals, allowing the transportation of water to virtually any point from any water source. Water quality is widely variable, from almost rain water to brackish, with a high frequency of sodium bicarbonate types. Return flows, especially when water is applied with good irrigation techniques and the original quality is poor, are saline and contain chemicals leached from the fertilizers. On Tenerife Island, most of the return flows go to coastal aquifers, while most of the water comes from high-altitude water galleries. Agricultural pollution is not generally appraised, but it exists. It can be masked by the frequent, high natural nitrate content in groundwater. On Gran Canaria Island, since water comes mainly from deep shaft wells near the irrigated areas, the nitrate pollution is much more clear. On La Palma Island, besides the nitrate pollution, a potassium pollution of agricultural origin has been mentioned. Other situations on the remaining islands are also discussed. It can be concluded that agriculture is a big concern for the water quality in many areas and impairs its suitability for other uses. Because of the great depth of the water table, the nitrate pollution may not become obvious for many years, especially for the deep-water galleries.

  13. Sustainable Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert

    2011-01-01

    The proposed Mars sample return mission will be completed using natural Martian resources for the majority of its operations. The system uses the following technologies: In-Situ Propellant Production (ISPP), a methane-oxygen propelled Mars Ascent Vehicle (MAV), a carbon dioxide powered hopper, and a hydrogen fueled balloon system (large balloons and small weather balloons). The ISPP system will produce the hydrogen, methane, and oxygen using a Sabatier reactor. a water electrolysis cell, water extracted from the Martian surface, and carbon dioxide extracted from the Martian atmosphere. Indigenous hydrogen will fuel the balloon systems and locally-derived methane and oxygen will fuel the MAV for the return of a 50 kg sample to Earth. The ISPP system will have a production cycle of 800 days and the estimated overall mission length is 1355 days from Earth departure to return to low Earth orbit. Combining these advanced technologies will enable the proposed sample return mission to be executed with reduced initial launch mass and thus be more cost efficient. The successful completion of this mission will serve as the next step in the advancement of Mars exploration technology.

  14. Higher Education Endowments Return

    ERIC Educational Resources Information Center

    Bahlmann, David; Walda, John D.; Sedlacek, Verne O.

    2012-01-01

    A new study of endowments by the National Association of College and University Business Officers (NACUBO) and the Commonfund Institute has brought good news to college and universities: While endowment returns dropped precipitously in fiscal year 2009 as a result of the financial crisis and accompanying slide in equity markets, they climbed to an…

  15. Return to Play

    ERIC Educational Resources Information Center

    Mangan, Marianne

    2013-01-01

    Call it physical activity, call it games, or call it play. Whatever its name, it's a place we all need to return to. In the physical education, recreation, and dance professions, we need to redesign programs to address the need for and want of play that is inherent in all of us.

  16. Phobos Sample Return mission

    NASA Astrophysics Data System (ADS)

    Zelenyi, Lev; Zakharov, A.; Martynov, M.; Polischuk, G.

    Very mysterious objects of the Solar system are the Martian satellites, Phobos and Deimos. Attempt to study Phobos in situ from an orbiter and from landers have been done by the Russian mission FOBOS in 1988. However, due to a malfunction of the onboard control system the landers have not been delivered to the Phobos surface. A new robotics mission to Phobos is under development now in Russia. Its main goal is the delivery of samples of the Phobos surface material to the Earth for laboratory studies of its chemical, isotopic, mineral composition, age etc. Other goals are in situ studies of Phobos (regolith, internal structure, peculiarities in orbital and proper rotation), studies of Martian environment (dust, plasma, fields). The payload includes a number of scientific instruments: gamma and neutron spectrometers, gaschromatograph, mass spectrometers, IR spectrometer, seismometer, panoramic camera, dust sensor, plasma package. To implement the tasks of this mission a cruise-transfer spacecraft after the launch and the Earth-Mars interplanetary flight will be inserted into the first elliptical orbit around Mars, then after several corrections the spacecraft orbit will be formed very close to the Phobos orbit to keep the synchronous orbiting with Phobos. Then the spacecraft will encounter with Phobos and will land at the surface. After the landing the sampling device of the spacecraft will collect several samples of the Phobos regolith and will load these samples into the return capsule mounted at the returned vehicle. This returned vehicle will be launched from the mother spacecraft and after the Mars-Earth interplanetary flight after 11 monthes with reach the terrestrial atmosphere. Before entering into the atmosphere the returned capsule will be separated from the returned vehicle and will hopefully land at the Earth surface. The mother spacecraft at the Phobos surface carrying onboard scientific instruments will implement the "in situ" experiments during an year

  17. Agricultural Microbiology.

    ERIC Educational Resources Information Center

    Brill, Winston J.

    1981-01-01

    Elucidates strategies for applying microbiological techniques to traditional agricultural practices. Discusses the manipulation of microorganisms that live with plants and also the problems involved in the introduction of new genes into crop plants by recombinant DNA methods. (CS)

  18. Agricultural Geophysics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The four geophysical methods predominantly used for agricultural purposes are resistivity, electromagnetic induction, ground penetrating radar (GPR), and time domain reflectometry (TDR). Resistivity and electromagnetic induction methods are typically employed to map lateral variations of apparent so...

  19. Assured Crew Return Vehicle

    NASA Technical Reports Server (NTRS)

    Stone, D. A.; Craig, J. W.; Drone, B.; Gerlach, R. H.; Williams, R. J.

    1991-01-01

    The developmental status is discussed regarding the 'lifeboat' vehicle to enhance the safety of the crew on the Space Station Freedom (SSF). NASA's Assured Crew Return Vehicle (ACRV) is intended to provide a means for returning the SSF crew to earth at all times. The 'lifeboat' philosophy is the key to managing the development of the ACRV which further depends on matrixed support and total quality management for implementation. The risk of SSF mission scenarios are related to selected ACRV mission requirements, and the system and vehicle designs are related to these precepts. Four possible ACRV configurations are mentioned including the lifting-body, Apollo shape, Discoverer shape, and a new lift-to-drag concept. The SCRAM design concept is discussed in detail with attention to the 'lifeboat' philosophy and requirements for implementation.

  20. Agricultural Waste.

    PubMed

    Shu, Huajie; Zhang, Panpan; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2015-10-01

    The management and disposal of agricultural waste are drawn more and more attention because of the increasing yields and negative effects on the environment. However, proper treatments such as converting abundant biomass wastes into biogas through anaerobic digestion technology, can not only avoid the negative impacts, but also convert waste into available resources. This review summarizes the studies of nearly two hundred scholars from the following four aspects: the characterization, reuse, treatment, and management of agricultural waste. PMID:26420088

  1. Modeling the effect of soil structure on water flow and isoproturon dynamics in an agricultural field receiving repeated urban waste compost application.

    PubMed

    Filipović, Vilim; Coquet, Yves; Pot, Valérie; Houot, Sabine; Benoit, Pierre

    2014-11-15

    Transport processes in soils are strongly affected by heterogeneity of soil hydraulic properties. Tillage practices and compost amendments can modify soil structure and create heterogeneity at the local scale within agricultural fields. The long-term field experiment QualiAgro (INRA-Veolia partnership 1998-2013) explores the impact of heterogeneity in soil structure created by tillage practices and compost application on transport processes. A modeling study was performed to evaluate how the presence of heterogeneity due to soil tillage and compost application affects water flow and pesticide dynamics in soil during a long-term period. The study was done on a plot receiving a co-compost of green wastes and sewage sludge (SGW) applied once every 2 years since 1998. The plot was cultivated with a biannual rotation of winter wheat-maize (except 1 year of barley) and a four-furrow moldboard plow was used for tillage. In each plot, wick lysimeter outflow and TDR probe data were collected at different depths from 2004, while tensiometer measurements were also conducted during 2007/2008. Isoproturon concentration was measured in lysimeter outflow since 2004. Detailed profile description was used to locate different soil structures in the profile, which was then implemented in the HYDRUS-2D model. Four zones were identified in the plowed layer: compacted clods with no visible macropores (Δ), non-compacted soil with visible macroporosity (Γ), interfurrows created by moldboard plowing containing crop residues and applied compost (IF), and the plow pan (PP) created by plowing repeatedly to the same depth. Isoproturon retention and degradation parameters were estimated from laboratory batch sorption and incubation experiments, respectively, for each structure independently. Water retention parameters were estimated from pressure plate laboratory measurements and hydraulic conductivity parameters were obtained from field tension infiltrometer experiments. Soil hydraulic

  2. Returns to Education in Bangladesh

    ERIC Educational Resources Information Center

    Asadullah, Mohammad Niaz

    2006-01-01

    This paper reports labour market returns to education in Bangladesh using data from recent nationwide household survey. Returns are estimated separately for rural and urban samples, males, females and private-sector employees. Substantial heterogeneity in returns is observed; for example, estimates are higher for urban (than rural sample) and…

  3. A Look at Returning Teachers

    ERIC Educational Resources Information Center

    DeAngelis, Karen J.

    2013-01-01

    Research shows that one-quarter to one-third of teachers who leave the profession return, the majority after only a short absence. Though returning teachers can constitute a substantial share of newly hired teachers in schools each year, little is known about them, the factors associated with their decisions to return, or the schools to which…

  4. Puerto Rican Return Migrant Youth.

    ERIC Educational Resources Information Center

    Carrasquillo, Angela; Carrasquillo, Ceferino

    Among Puerto Ricans who have migrated to the United States, a significant number have returned to Puerto Rico, while others shuttle between Puerto Rico and the United States. These groups of people are identified as return migrants. Studies suggest that return migrant youth in Puerto Rico have had to make environmental and cultural adjustments…

  5. HYDROGEOLOGIC FOUNDATION IN SUPPORT OF ECOSYSTEM RESTORATION: BASE-FLOW LOADINGS OF NITRATE IN MID-ATLANTIC AGRICULTURAL WATERSHEDS (EPA/600/R-99/104)

    EPA Science Inventory

    Field evidence suggests that deep denitrification in the subsurface has the potential forremoval of nitrate from ground water. Two adjacent agricultural watersheds in the mid-Atlantic coastal plain display remarkable differences in their ground-water nitrate discharges.It is b...

  6. Sample Return Science

    NASA Astrophysics Data System (ADS)

    Williford, K. H.; Allwood, A.; Beegle, L. W.; Bhartia, R.; Flannery, D.; Hoffmann, A.; Mora, M. F.; Orbay, J.; Petrizzo, D. A.; Tuite, M. L., Jr.; Willis, P. A.

    2014-12-01

    The first clear identification of an ancient habitable environment on Mars by the Mars Science Laboratory (MSL) rover mission relied on a synthetic analytical approach combining orbital and surface imagery and spectroscopy with sophisticated sample acquisition and handling technology including a rotary percussive drill that provided powdered rock for bulk geochemical analysis [1]. The recent announcement of the instrument package for the proposed NASA Mars2020 rover mission, including micro x-ray fluorescence (PIXL) for elemental mapping as well as scanning ultraviolet laser fluorescence and Raman (SHERLOC) suggests a shift in emphasis of Mars surface science towards spatially resolved geochemical analysis that will support the selection and acquisition of samples for coring, caching, and possible return to Earth for further analysis. During a recent field expedition to investigate Archean and Proterozoic biosignatures in the Pilbara region of Western Australia, we deployed a dry, rotary percussive coring drill with a bit assembly analogous to that being considered for Mars2020. Six targets of varying age and lithology were sampled with the coring drill, and surrounding and adjacent rock samples were collected simultaneously. These samples were subsequently prepared and subsampled for bulk and in situ, spatially resolved analysis using conventional laboratory methods as well as the existing PIXL and SHERLOC platforms currently in development. Here we present new approaches and data from this integrated and ongoing program of "sample return science" designed to simulate, and eventually reduce risk associated with a long-term effort towards Mars sample return. [1] Grotzinger, J.P. et al. 2014. Science 343 DOI: 10.1126/science.1242777.

  7. Mars sample return - Science

    NASA Technical Reports Server (NTRS)

    Blanchard, Douglas P.

    1988-01-01

    The possible scientific goals of a Mars sample return mission are reviewed, including the value of samples and the selection of sampling sites. The fundamental questions about Mars which could be studied using samples are examined, including planetary formation, differentiation, volcanism and petrogenesis, weathering, and erosion. Scenarios are presented for sample acquisition and analysis. Possible sampling methods and tools are discussed, including drilling techniques, types of rovers, and processing instruments. In addition, the possibility of aerocapture out of elliptical or circular orbit is considered.

  8. Titan Science Return Quantification

    NASA Technical Reports Server (NTRS)

    Weisbin, Charles R.; Lincoln, William

    2014-01-01

    Each proposal for a NASA mission concept includes a Science Traceability Matrix (STM), intended to show that what is being proposed would contribute to satisfying one or more of the agency's top-level science goals. But the information traditionally provided cannot be used directly to quantitatively compare anticipated science return. We added numerical elements to NASA's STM and developed a software tool to process the data. We then applied this methodology to evaluate a group of competing concepts for a proposed mission to Saturn's moon, Titan.

  9. Agricultural Biodiversity.

    ERIC Educational Resources Information Center

    Postance, Jim

    1998-01-01

    The extinction of farm animals and crops is rarely brought up during discussions of endangered species and biodiversity; however, the loss of diversity in crops and livestock threatens the sustainability of agriculture. Presents three activities: (1) "The Colors of Diversity"; (2) "Biodiversity among Animals"; and (3) "Heirloom Plants." Discusses…

  10. AGRICULTURAL EXTENSION.

    ERIC Educational Resources Information Center

    FARQUHAR, R.N.

    AUSTRALIAN AGRICULTURAL EXTENSION HAS LONG EMPHASIZED TECHNICAL ADVISORY SERVICE AT THE EXPENSE OF THE SOCIOECONOMIC ASPECTS OF FARM PRODUCTION AND FARM LIFE. ONLY IN TASMANIA HAS FARM MANAGEMENT BEEN STRESSED. DEMANDS FOR THE WHOLE-FARM APPROACH HAVE PRODUCED A TREND TOWARD GENERALISM FOR DISTRICT OFFICERS IN MOST STATES. THE FEDERAL GOVERNMENT,…

  11. AGRICULTURAL EDUCATION.

    ERIC Educational Resources Information Center

    DEALTON, ERNEST L.

    TODAY'S SUCCESSFUL FARMER MUST POSSESS THE SKILLS OF A BUSINESSMAN, SCIENTIST, AND MECHANIC TO SURVIVE COMPETITION IN AGRICULTURE, THE LARGEST INDUSTRY IN THE UNITED STATES. THIS COMPETITION HAS CAUSED AN INCREASE IN THE SIZE OF FARMS AND RANCHES IN AN ATTEMPT TO CURTAIL OPERATIONAL EXPENSES AND TO INCREASE PRODUCTION. WITH THE SCIENTIFIC…

  12. Agriculture and climate change

    SciTech Connect

    Abelson, P.H.

    1992-07-03

    How will increases in levels of CO{sub 2} and changes in temperature affect food production A recently issued report analyzes prospects for US agriculture 1990 to 2030. The report, prepared by a distinguished Task Force, first projects the evolution of agriculture assuming increased levels of CO{sub 2} but no climate change. Then it deals with effects of climate change, followed by a discussion of how greenhouse emissions might be diminished by agriculture. Economic and policy matters are also covered. How the climate would respond to more greenhouse gases is uncertain. If temperatures were higher, there would be more evaporation and more precipitation. Where would the rain fall That is a good question. Weather in a particular locality is not determined by global averages. The Dust Bowl of the 1930s could be repeated at its former site or located in another region such as the present Corn Belt. But depending on the realities at a given place, farmers have demonstrated great flexibility in choosing what they may grow. Their flexibility has been increased by the numerous varieties of seeds of major crops that are now available, each having different characteristics such as drought resistance and temperature tolerance. In past, agriculture has contributed about 5% of US greenhouse gases. Two large components have involved emissions of CO{sub 2} from farm machinery and from oxidation of organic matter in soil due to tillage. Use of diesel fuel and more efficient machinery has reduced emissions from that source by 40%. In some areas changed tillage practices are now responsible for returning carbon to the soil. The report identifies an important potential for diminishing net US emissions of CO{sub 2} by growth and utilization of biomass. Large areas are already available that could be devoted to energy crops.

  13. 7 CFR 46.21 - Returns, rejections, or credit memorandums on sales.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Returns, rejections, or credit memorandums on sales... COMMODITIES ACT, 1930 Records of Market Receivers § 46.21 Returns, rejections, or credit memorandums on sales..., a credit memorandum showing the buyer's name, sales ticket number, lot number, date of the...

  14. U and Sr Isotope Tracers of Agricultural Salinity Sources to the Lower Rio Grande River

    NASA Astrophysics Data System (ADS)

    Nyachoti, S. K.; Ma, L.; Szynkiewicz, A.; Jin, L.; McIntosh, J. C.

    2014-12-01

    Elevated salinity of the lower Rio Grande River deteriorates water quality and limits domestic and agricultural water use. Both natural and anthropogenic processes contribute salts in the Rio Grande. Previous studies have focused on natural salt contributions with less emphasis on anthropogenic sources of salinity in the Rio Grande. Using (234U/238U) activity ratios (UAR), 87Sr/86Sr isotope ratios, and major element concentrations, we aim to trace and quantify the salt loads in the Lower Rio Grande watershed which is greatly impacted by agricultural activities. Between 2009 and 2010, we sampled the Rio Grande stretch and irrigation return flows between the Elephant Butte Reservoir, New Mexico and El Paso, Texas. Furthermore, we monitored in monthly intervals the temporal changes of chemical and isotopic compositions of the Rio Grande at Canutillo, Tx. Our results show higher U and Sr fluxes in the Rio Grande during the irrigation season as compared to the non-irrigation season. The UAR (1.62 to 2.13) and 87Sr/86Sr ratios (0.7099 to 0.7138) were higher in the non-irrigation season compared to the irrigation season (UAR: 1.69 to 1.77; 87Sr/86Sr: 0.7100 to 0.7106). These variations of UAR and 87Sr/86Sr ratios imply multiple sources of U and Sr in the Rio Grande. In contrast, the agricultural return flows show a narrow range of UAR (1.31 to 1.37) and 87Sr/86Sr ratios (0.7091 to 0.7099) in the studied seasons. This is consistent with salinity contributions from agricultural sources. Rio Grande at Canutillo shows low UAR (1.62 to 1.77) and 87Sr/86Sr ratios (0.7104 to 0.7105) during the irrigation season as compared to the non-irrigation season (UAR: 2.04 to 2.24; 87Sr/86Sr: 0.7105 to 0.7109). The low U and Sr signature at Canutillo during the irrigation season is close to that of the agricultural return flows, indicative of agricultural salinity sources. These results provide useful elemental and isotopic constraints for future mass balance calculations of salinity

  15. Returning Samples from Enceladus

    NASA Astrophysics Data System (ADS)

    Tsou, P.; Kanik, I.; Brownlee, D.; McKay, C.; Anbar, A.; Glavin, D.; Yano, H.

    2012-12-01

    From the first half century of space exploration, we have obtained samples only from the Moon, comet Wild 2, the Solar Wind and the asteroid Itokawa. The in-depth analyses of these samples in terrestrial laboratories have yielded profound knowledge that could not have been obtained without the returned samples. While obtaining samples from Solar System bodies is crucial science, it is rarely done due to cost and complexity. Cassini's discovery of geysers on Enceladus and organic materials, indicate that there is an exceptional opportunity and science rational to do a low-cost flyby sample return mission, similar to what was done by the Stardust. The earliest low cost possible flight opportunity is the next Discovery Mission [Tsou et al 2012]. Enceladus Plume Discovery - While Voyager provided evidence for young surfaces on Enceladus, the existence of Enceladus plumes was discovered by Cassini. Enceladus and comets are the only known solar system bodies that have jets enabling sample collection without landing or surface contact. Cassini in situ Findings -Cassini's made many discoveries at Saturn, including the break up of large organics in the plumes of Enceladus. Four prime criteria for habitability are liquid water, a heat source, organics and nitrogen [McKay et al. 2008, Waite et al. 2009, Postberg et al. 2011]. Out of all the NASA designated habitability targets, Enceladus is the single body that presents evidence for all four criteria. Significant advancement in the exploration of the biological potential of Enceladus can be made on returned samples in terrestrial laboratories where the full power of state-of-the-art laboratory instrumentation and procedures can be used. Without serious limits on power, mass or even cost, terrestrial laboratories provide the ultimate in analytical capability, adaptability, reproducibility and reliability. What Questions can Samples Address? - Samples collected from the Enceladus plume will enable a thorough and replicated

  16. Return to Space

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This video documents the preparations for Shuttle Flight STS-26 with Shuttle Discovery, NASA's return to manned space flight after the Challenger disaster. Footage and descriptions document such changes to the new Shuttle as new joints, improved insulation, and added O-rings to the solid rocket boosters; new safety hardware and procedures such as parachute and sidewire evacuations during liftoff, and new pressure suits; modified landing gear, brakes, and nose wheel steering, as well as a modified landing runway. Also profiled are the 5 member crew of all veteran Shuttle astronauts, the TDRS 3 Satellite to be released from the cargo bay in orbit, and 11 commercial and student experiments to be performed during the mission.

  17. Dealing with returned manuscripts.

    PubMed

    Peh, W C G; Ng, K H

    2009-11-01

    It is useful for authors to learn to deal with returned manuscripts with a rejection decision or a request for revision. Common reasons for rejection include contents outside the scope of the journal or inappropriate for the journal, incomplete submission, poor methodology, faulty experimental design, major flaws in the interpretation of results, extremely poor writing, and duplicated or plagiarised work. Authors should use the editor's and reviewers' comments to improve their manuscripts and resubmit elsewhere. Common reasons for revision requests include minor faults in the methodology, minor inaccuracies in data, inconsistencies among different sections of the manuscript, faulty deductions, data that do not support the conclusions, excessive data or text, poor or excessive illustrations, and poor but salvageable writing. A request for revision should be viewed positively, as it means that there is a possibility that the manuscript may still be potentially publishable, provided that all the editor's and reviewers' comments are addressed. PMID:19960157

  18. Return to space

    NASA Astrophysics Data System (ADS)

    1989-08-01

    This video documents the preparations for Shuttle Flight STS-26 with Shuttle Discovery, NASA's return to manned space flight after the Challenger disaster. Footage and descriptions document such changes to the new Shuttle as new joints, improved insulation, and added O-rings to the solid rocket boosters; new safety hardware and procedures such as parachute and sidewire evacuations during liftoff, and new pressure suits; modified landing gear, brakes, and nose wheel steering, as well as a modified landing runway. Also profiled are the 5 member crew of all veteran Shuttle astronauts, the TDRS 3 Satellite to be released from the cargo bay in orbit, and 11 commercial and student experiments to be performed during the mission.

  19. Aerodynamics of Stardust Sample Return Capsule

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.; Wilmoth, R. G.; Cheatwood, F. M.; Brauckmann, G. J.; Greene, F. A.

    1997-01-01

    Successful return of interstellar dust and cometary material by the Stardust Sample Return Capsule requires an accurate description of the Earth entry vehicle's aerodynamics. This description must span the hypersonic-rarefied, hypersonic-continuum, supersonic, transonic, and subsonic flow regimes. Data from numerous sources are compiled to accomplish this objective. These include Direct Simulation Monte Carlo analyses, thermochemical nonequilibrium computational fluid dynamics, transonic computational fluid dynamics, existing wind tunnel data, and new wind tunnel data. Four observations are highlighted: 1) a static instability is revealed in the free-molecular and early transitional-flow regime due to aft location of the vehicle s center-of-gravity, 2) the aerodynamics across the hypersonic regime are compared with the Newtonian flow approximation and a correlation between the accuracy of the Newtonian flow assumption and the sonic line position is noted, 3) the primary effect of shape change due to ablation is shown to be a reduction in drag, and 4) a subsonic dynamic instability is revealed which will necessitate either a change in the vehicle s center-of-gravity location or the use of a stabilizing drogue parachute.

  20. 17. Internal view of boiler in steam space above return ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Internal view of boiler in steam space above return flues. View looks forward in ship toward fireboxes; tubes (flues) below carry hot combustion gases from return chamber to smoke chamber. From thence gasses flow through vertical pipe at left into steam stack, and eventually to ship's smokestack. Inclined and radiating straps are stays used to reinforce boiler plates against distortion under pressure. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

  1. 11. VIEW OF A SITE RETURN WEAPONS COMPONENT. SITE RETURNS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. VIEW OF A SITE RETURN WEAPONS COMPONENT. SITE RETURNS WERE NUCLEAR WEAPONS SHIPPED TO THE ROCKY FLATS PLANT FROM THE NUCLEAR WEAPON STOCKPILE FOR RETIREMENT, TESTING, OR UPGRADING. FISSILE MATERIALS (PLUTONIUM, URANIUM, ETC.) AND RARE MATERIALS (BERYLLIUM) WERE RECOVERED FOR REUSE, AND THE REMAINDER WAS DISPOSED. (8/7/62) - Rocky Flats Plant, Plutonium Fabrication, Central section of Plant, Golden, Jefferson County, CO

  2. Christmas Island birds returning

    NASA Astrophysics Data System (ADS)

    Six months after their mass exodus, birds are beginning to return to Christmas Island. Roughly 17 million birds, almost the entire adult bird population, either perished or fled their mid-Pacific atoll home last autumn, leaving behind thousands of nestlings to starve (Eos, April 5, 1983, p. 131). It is believed that the strong El Niño altered the ecology of the surrounding waters and forced the birds to flee. Christmas Island is the world's largest coral atoll.“Ocean and atmosphere scientists are unsure of future directions for the El Niño conditions and cannot now predict what will happen to the birds in the coming months,” said Ralph W. Schreiber, curator of ornithology at the Natural History Museum of Los Angeles County in California. Heisthe ornithologist who discovered the disappearance. “The recovery of the bird populations depends on the food supply in the waters surrounding the island.” The island's birds feed exclusively on small fish and squid.

  3. The Point of No Return

    PubMed Central

    Logan, Gordon D.

    2015-01-01

    Bartlett (1958) described the point of no return as a point of irrevocable commitment to action, which was preceded by a period of gradually increasing commitment. As such, the point of no return reflects a fundamental limit on the ability to control thought and action. I review the literature on the point of no return, taking three perspectives. First, I consider the point of no return from the perspective of the controlled act, as a locus in the architecture and anatomy of the underlying processes. I review experiments from the stop-signal paradigm that suggest that the point of no return is located late in the response system. Then I consider the point of no return from the perspective of the act of control that tries to change the controlled act before it becomes irrevocable. From this perspective, the point of no return is a point in time that provides enough “lead time” for the act of control to take effect. I review experiments that measure the response time to the stop signal as the lead time required for response inhibition in the stop-signal paradigm. Finally, I consider the point of no return in hierarchically controlled tasks, in which there may be many points of no return at different levels of the hierarchy. I review experiments on skilled typing that suggest different points of no return for the commands that determine what is typed and the countermands that inhibit typing, with increasing commitment to action the lower the level in the hierarchy. I end by considering the point of no return in perception and thought as well as action. PMID:25633089

  4. Animal Enterprise Record Book. Agricultural Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Agricultural Curriculum Materials Service.

    This record book is intended for use by agricultural education students who have ownership arrangements in animal enterprise experience programs. A major purpose of this book is to aid in separating out or allocating the costs and returns to a specific enterprise. The financial, labor, and management aspects of each enterprise can then be studied…

  5. FLOW SYSTEM FOR REACTOR

    DOEpatents

    Zinn, W.H.

    1963-06-11

    A reactor is designed with means for terminating the reaction when returning coolant is below a predetermined temperature. Coolant flowing from the reactor passes through a heat exchanger to a lower reservoir, and then circulates between the lower reservoir and an upper reservoir before being returned to the reactor. Means responsive to the temperature of the coolant in the return conduit terminate the chain reaction when the temperature reaches a predetermined minimum value. (AEC)

  6. Non-Returning Student Survey.

    ERIC Educational Resources Information Center

    Charles County Community Coll., La Plata, MD. Dept. of Institutional Research and Assessment.

    In spring 1992, Charles County Community College (CCCC) conducted a telephone survey of non-returning fall 1991 students to determine their reasons for not returning to CCCC. In order to obtain comparison data, a questionnaire designed and administered by Prince George's Community College (PGCC) (Largo, Maryland) in 1988 was used with one minor…

  7. Capital Structure and Stock Returns

    ERIC Educational Resources Information Center

    Welch, Ivo

    2004-01-01

    U.S. corporations do not issue and repurchase debt and equity to counteract the mechanistic effects of stock returns on their debt-equity ratios. Thus over one- to five-year horizons, stock returns can explain about 40 percent of debt ratio dynamics. Although corporate net issuing activity is lively and although it can explain 60 percent of debt…

  8. A RESEARCH STUDY OF AGRICULTURAL TRAINING NEEDS IN VENTURA COUNTY.

    ERIC Educational Resources Information Center

    RODRIGUES, DONALD F.

    QUESTIONNAIRE RETURNS FROM 103 EMPLOYERS IN AGRICULTURE AND RELATED INDUSTRIES WERE COMBINED WITH 50 INTERVIEWS WITHIN THE SAME GROUP TO PROVIDE INFORMATION ABOUT AGRICULTURAL TRAINING NEEDS IN VENTURA COUNTY. MOST FIRMS EMPLOYED FEWER THAN 15 WORKERS ON A PERMANENT BASIS, SUPPLEMENTED BY LARGE MEMBERS OF SEASONAL WORKERS, ESPECIALLY IN THE…

  9. Trophic relationships of small nonnative fishes in a natural creek and several agricultural drains flowing into the Salton Sea, and their potential, effects on the endangered desert pupfish

    USGS Publications Warehouse

    Martin, Barbara A.; Saiki, Michael K.

    2009-01-01

    This study was conducted to characterize trophic relationships of small nonnative fishes and to determine if predation by these fishes contributes to the decline of desert pupfish (Cyprinodon macularius), an endangered cyprinodont on the verge of extinction. We sampled 403 hybrid Mozambique tilapias (Oreochromis mossambica by O. urolepis), 107 redbelly tilapias (Tilapia zillii), 32 longjaw mudsuckers (Gillkhthys mirabilis), 182 western mosquitofish (Gambusia affinis), 222 sailfin mollies (Poecilia latipinna), 63 shortfin mollies (Poecilia mexicana), and 235 porthole livebearers (Poecilurpsis gracilis) from a natural creek and four agricultural drains during September 1999- December 2001. Evidence of piscivory was in gastrointestinal contents of 14 hybrid Mozambique tilapias, 3 redbelly tilapias, 10 longjaw mudsuckers, 8 western mosquitofish, 2 sailfin mollies, and 8 porthole livebearers. Although digestion often was too advanced for identification of fishes consumed by nonnative fishes, remains of desert pupfish were in gastrointestinal contents of a longjaw mudsucker. Our findings, along with Field evidence from other studies that inverse relationships exist between abundances of desert pupfish and nonnative species, are consistent with the hypothesis that predation by nonnative species is contributing to decline of desert pupfish. We suspect that competitive interactions with nonnative fishes might also adversely affect abundance of desert pupfish.

  10. APOLLO 11: The heroes Return

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The crew of APOLLO 11 return as heroes after their succesfull landing on the lunar surface. From the film documentary 'APOLLO 11:'The Eagle Has Landed'', part of a documentary series on the APOLLO missions made in the early '70's and narrated by Burgess Meredith. APOLLO 11: First manned lunar landing and return to Earth with Neil A. Armstrong, Michael Collins, and Edwin E. Aldrin. Landed in the Sea of Tranquilityon July 20, 1969; deployed TV camera and EASEP experiments, performed lunar surface EVA, returned lunar soil samples. Mission Duration 195 hrs 18 min 35sec

  11. Variational principles for the return current in encephalography

    SciTech Connect

    Heller, L.

    1989-01-01

    The total electric current within the brain has been written as a sum of two terms, of distinctly different nature. The first, /rvec J//sup /iota//, is the 'primary' or 'impressed' intracellular current that flows within the neurons, and is the quantity of interest in neuroscience. This current leaks across the cell membrane, however, and since the cells are embedded in an electrically conducting medium the extracellular ('return') current flows through a large volume of this medium before returning to the cell. With the return current written as the product of the conductivity /sigma/ and the electric field intensity /rvec E/ = /minus//del/V, at low frequencies the electric potential V is determined by the continuity equation. 9 refs.

  12. 28 CFR 540.24 - Returned mail.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... contraband all undelivered mail returned to an institution by the Post Office before returning it to the.... Any returned mail qualifying as “special mail” is opened and inspected for contraband in the...

  13. 28 CFR 540.24 - Returned mail.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contraband all undelivered mail returned to an institution by the Post Office before returning it to the.... Any returned mail qualifying as “special mail” is opened and inspected for contraband in the...

  14. The Fertile Grounds Initiative: A new way to close nutrient flows at regional level resulting in better agricultural productivity and less environmental losses

    NASA Astrophysics Data System (ADS)

    van Beek, Christy; van Duivenbooden, Niek; Noij, Gert-Jan

    2014-05-01

    The threat of declining soil fertility levels is well known. Yet, and despite numerous efforts, we seem incapable of changing the current situation of sink areas in developed countries and depletion areas in developing countries. With negative consequences (i.e. loss in productive capacity and loss in environmental quality) in both areas. Moreover, due to globalization and urbanization nutrient flows become increasingly disconnected. Soil nutrient depletion cannot simply be compensated for with mineral fertilisers, for the following reasons: • mineral fertilisers are often not affordable for smallholders and fertiliser subsidy systems are not always successful • mineral fertilisers do not contain organic matter and therefore do not halt the degradation of the soil • mineral fertilisers work best in combination with organic sources of nutrients (compost, farm yard manure, etc.) • To halt soil degradation an integrated approach is needed, including reducing losses of nutrients and organic matter from soils at risk. Presently, more actors are getting involved in reallocation of nutrients, especially in the energy and waste sector. Time has come for a new approach to bring together demands and supplies for nutrients. We therefore present the Fertile Grounds Initiative: a broker for nutrient supply and demand in the region. The Fertile Grounds Initiative is based on the findings that: • Organic ánd mineral nutrients are required for increased and sustainable production; • Nutrients have a value and should be treated as such; • Due to globalization and urbanization nutrient flows are ever more polarized between depletion and concentration areas; • The demand for energy poses new threats and opportunities for nutrient management. In the Fertile Grounds Initiative nutrient suppliers from the energy sector, waste management, fertilizer companies, etc. and demands for nutrients from farmers are brought together in a dynamic platform. This platform acts as a

  15. Programs in Animal Agriculture.

    ERIC Educational Resources Information Center

    Herring, Don R.; And Others

    1980-01-01

    Five topics relating to programs in animal agriculture are addressed: (1) the future of animal agriculture; (2) preparing teachers in animal agriculture; (3) how animal programs help young people; (4) a nontraditional animal agriculture program; and (5) developing competencies in animal agriculture. (LRA)

  16. Predictors of returning to work.

    PubMed

    Ash, P; Goldstein, S I

    1995-01-01

    An investigation of predictors of returning to work in a sample of physically injured persons who are receiving workers' compensation benefits and vocational rehabilitation is presented. One hundred fourteen injured subjects (86 with back injury; 28, other injury) undergoing vocational rehabilitation and receiving workers' compensation benefits were assessed on demographic, emotional, cognitive, financial incentive, and miscellaneous variables. Predictors for returning to work were identified using stepwise logistic regression. Patients with moderate or severe depression, defined as a score greater than 16 on the Beck Depression Inventory (BDI), were significantly less likely to return to work following vocational rehabilitation efforts than patients with less severe depression (for back-injured patients, odds ratio (OR) = 31, 95% CI [8.8, 108]). BDI scores correctly classified 84 percent of the back-injury and 86% of the other-injury groups with respect to their return to work. The level of workers' compensation benefit was the only variable that added (marginally) to the predictive power of the BDI. In a physically injured population receiving workers' compensation benefits, who are judged to be not clearly permanently disabled, level of depressive symptoms is a strong predictor of returning to work. Caution is warranted in using the BDI as the sole determinant in a forensic situation for making a real-world prediction, as BDI responses are easy to fake. Treatment of concurrent depression is an important component of helping physically injured workers resume gainful employment. PMID:8605404

  17. Private and Social Rates of Return to Higher Education in Science and Technology in a Caribbean Economy.

    ERIC Educational Resources Information Center

    Bourne, Compton; Dass, Anand

    2003-01-01

    Estimates private and social rates of return for university science and technology graduates in Trinidad and Tobago. Makes comparisons with other fields of study such as agriculture, natural sciences, engineering, and humanities. Concludes that rates of return are inconsistent with the allocative preferences of policymakers. (Authors/PKP)

  18. 7 CFR 735.7 - Return of suspended or revoked certificates of licensing or certificates of authorization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Return of suspended or revoked certificates of... FOR THE UNITED STATES WAREHOUSE ACT General Provisions § 735.7 Return of suspended or revoked... or service license ends or is suspended or revoked by DACO, such certificates of licensing...

  19. Agricultural production and stability of settlement systems in Upper Mesopotamia during the Early Bronze Age (third millennium BCE)

    NASA Astrophysics Data System (ADS)

    Kalayci, Tuna

    This study investigates the relationship between rainfall variation and rain-fed agricultural production in Upper Mesopotamia with a specific focus on Early Bronze Age urban settlements. In return, the variation in production is used to explore stability of urban settlement systems. The organization of the flow of agricultural goods is the key to sustaining the total settlement system. The vulnerability of a settlement system increases due to the increased demand for more output from agricultural lands. This demand is the key for the success of urbanization project. However, without estimating how many foodstuffs were available at the end of a production cycle, further discussions on the forces that shaped and sustained urban settlement systems will be lacking. While large scale fluctuations in the flow of agricultural products between settlements are not the only determinants of hierarchical structures, the total available agricultural yield for each urban settlement in a hierarchy must have influenced settlement relations. As for the methodology, first, Early Bronze Age precipitation levels are estimated by using modern day associations between the eastern Mediterranean coastal areas and the inner regions of Upper Mesopotamia. Next, these levels are integrated into a remote-sensing based biological growth model. Also, a CORONA satellite imagery based archaeological survey is conducted in order to map the Early Bronze Age settlement system in its entirety as well as the ancient markers of agricultural intensification. Finally, ancient agricultural production landscapes are modeled in a GIS. The study takes a critical position towards the traditionally held assumption that large urban settlements (cities) in Upper Mesopotamia were in a state of constant demand for food. The results from this study also suggest that when variations in ancient precipitation levels are translated into the variations in production levels, the impact of climatic aridification on ancient

  20. Atrial natriuretic peptide increases resistance to venous return in rats

    SciTech Connect

    Chien, Y.W.; Frohlich, E.D.; Trippodo, N.C.

    1987-05-01

    To examine mechanisms by which administration of atrial natriuretic peptide (ANP) decreases venous return, the authors compared the hemodynamic effects of ANP furosemide (FU), and hexamethonium (HEX) with those of vehicle (VE) in anesthetized rats. Compared with VE, ANP reduced mean arterial pressure, central venous pressure, and cardiac index and increased calculated resistance to venous return. /sup 141/Ce-labeled microspheres were used to determine cardiac output. Mean circulatory filling pressure, distribution of blood flow between splanchnic organs and skeletal muscles, and total peripheral resistance remained unchanged. FU increased urine output similar to that of ANP, yet produced no hemodynamic changes, dissociating diuresis, and decreased cardiac output. HEX lowered arterial pressure through a reduction in total peripheral resistance without altering cardiac output or resistance to venous return. The results confirm previous findings that ANP decreases cardiac output through a reduction in venous return and suggest that this results partly from increased resistance to venous return and not from venodilation or distribution of blood flow.

  1. Uncertain Educational Returns in a Developing Economy

    ERIC Educational Resources Information Center

    Mohapatra, Sandeep; Luckert, Martin K.

    2012-01-01

    This paper estimates the distribution of educational returns by gender for India. While previous studies focus on mean returns, the variance of educational returns has important implications for policy-making and micro-level decision making with respect to education. If the variance of educational returns is large, it can leave large sections of…

  2. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information and Returns § 1.6001-2 Returns. For rules relating to returns required...

  3. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information and Returns § 1.6001-2 Returns. For rules relating to returns required...

  4. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Information and Returns § 1.6001-2 Returns. For rules relating to returns required...

  5. 26 CFR 1.6001-2 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Returns. 1.6001-2 Section 1.6001-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Information and Returns § 1.6001-2 Returns. For rules relating to returns required to be made...

  6. The Genesis Solar Wind Sample Return Mission

    NASA Technical Reports Server (NTRS)

    Wiens, Roger C.; Burnett, Donald S.; Neugebauer, Marcia; Sasaki, Chester; Sevilla, Donald; Stansbery, Eileen; Clark, Ben; Smith, Nick; Oldham, Lloyd

    1990-01-01

    The Genesis spacecraft was launched on August 8 from Cape Canaveral on a journey to become the first spacecraft to return from interplanetary space. The fifth in NASA's line of low-cost Discovery-class missions, its goal is to collect samples of solar wind and return them to Earth for detailed isotopic and elemental analysis. The spacecraft is to collect solar wind for over two years, while circling the L1 point 1.5 million km sunward of the earth, before heading back for a capsule-style re-entry in September, 2004. After parachute deployment, a mid-air helicopter recovery will be used to avoid a hard landing. The mission has been in the planning stages for over ten years. Its cost, including development, mission operations, and sample analysis, is approximately $209M. The Genesis science team, headed by principal investigator Donald Burnett of Caltech, consists of approximately 20 co-investigators from universities and science centers around the country and internationally. The spacecraft consists of a relatively flat spacecraft bus containing most of the subsystem components, situated below a sample return capsule (SRC) which holds the solar-wind collection substrates and an electrostatic solar wind concentrator. Some of the collectors are exposed throughout the collection period, for a sample of bulk solar wind, while others are exposed only to certain solar wind regimes, or types of flow. Ion and electron spectrometers feed raw data to the spacecraft control and data-handling (C&DH) unit, which determines ion moments and electron flux geometries in real time. An algorithm is used to robotically decide between interstream (IS), coronal hole (CH), and coronal mass ejection (CME) regimes, and to control deployment of the proper arrays to sample these wind regimes independently. This is the first time such a solar-wind decision algorithm has been used on board a spacecraft.

  7. Return to the Red Planet

    NASA Technical Reports Server (NTRS)

    Lee, W.

    1996-01-01

    In November 1996, NASA and the Jet Propulsion Laboratory will begin America's return to Mars after a 20-year absence by launching the Mars Global Surveyor (MGS) spacecraft. This mission will usher in a new and exciting era of scientific missions to study the red planet.

  8. Return to the Social Studies.

    ERIC Educational Resources Information Center

    Consuela, Sister Mary

    In this speech, a plea is made to return content to the social studies. Content is seen as essential to cognitive and affective learning. Although the author feels that the introduction of behavioral objectives is a significant development of the various social studies projects, it is meaningless unless it is related to content. Clearly stated…

  9. Comet coma sample return instrument

    NASA Technical Reports Server (NTRS)

    Albee, A. L.; Brownlee, Don E.; Burnett, Donald S.; Tsou, Peter; Uesugi, K. T.

    1994-01-01

    The sample collection technology and instrument concept for the Sample of Comet Coma Earth Return Mission (SOCCER) are described. The scientific goals of this Flyby Sample Return are to return to coma dust and volatile samples from a known comet source, which will permit accurate elemental and isotopic measurements for thousands of individual solid particles and volatiles, detailed analysis of the dust structure, morphology, and mineralogy of the intact samples, and identification of the biogenic elements or compounds in the solid and volatile samples. Having these intact samples, morphologic, petrographic, and phase structural features can be determined. Information on dust particle size, shape, and density can be ascertained by analyzing penetration holes and tracks in the capture medium. Time and spatial data of dust capture will provide understanding of the flux dynamics of the coma and the jets. Additional information will include the identification of cosmic ray tracks in the cometary grains, which can provide a particle's process history and perhaps even the age of the comet. The measurements will be made with the same equipment used for studying micrometeorites for decades past; hence, the results can be directly compared without extrapolation or modification. The data will provide a powerful and direct technique for comparing the cometary samples with all known types of meteorites and interplanetary dust. This sample collection system will provide the first sample return from a specifically identified primitive body and will allow, for the first time, a direct method of matching meteoritic materials captured on Earth with known parent bodies.

  10. Neurocognitive Performance: Returning to Competition

    ERIC Educational Resources Information Center

    McDaniel, Larry W.; McIntire, Kyle

    2010-01-01

    Athletes who suffer from concussions under report their symptoms in order to expedite their return to competition. Athletic trainers and coaches must be aware of what is going on with athletes, even if it means requiring them to refrain from competition. Ninety percent of concussions are minor and can be difficult to diagnosis. There is a lack of…

  11. Skin lesions in returning travellers.

    PubMed

    Korzeniewski, Krzysztof; Juszczak, Dariusz; Jerzemowski, Janusz

    2015-01-01

    Skin lesions, apart from diarrhoeas, fever of unknown origin, and respiratory tract infections belong to the most frequent medical problems in travellers returned from tropical and subtropical destinations, accounting more than 10% of reported cases. Most dermatoses have their clinical onset during travel, although some of them can occur after return. Travel-related dermatological problems can have a wide spectrum of clinical picture, from macular, popular or nodular rash, linear and migratory lesions, to plaques, vesicles, bullae, erosions or ulcers. Skin conditions in returning travellers may be of infectious and non-infectious aetiologies. Infectious lesions may be originally tropical (e.g. dengue, chikungunya, schistosomiasis, leishmaniasis, myiasis, tungiasis, loiasis), although the majority are cosmopolitan (arthropod bites, sunburns, allergic rashes). The evaluation of skin lesions depends on many factors, including immune status of patients, use of medicines, exposure on health hazards (fauna, flora, risky behaviours), as well as the time, duration and location of travel. As the number of travellers to tropical and subtropical destinations has been continuously rising, the number of skin illnesses has also been increasing. This means that specialists in travel medicine need to extend their knowledge of epidemiology, clinical features and diagnosis of travel-related health problems including skin lesions in returning travellers. PMID:26394319

  12. The Returns to Apprenticeship Training

    ERIC Educational Resources Information Center

    McIntosh, Steven

    2005-01-01

    This paper uses recent data from the UK Labour Force Survey to estimate the wage gains that individuals make on average if they complete an apprenticeship programme. The results suggest gains of around 5-7% for men, but no benefit for women. Further analysis extends the results by considering the returns by age group, by qualification obtained, by…

  13. The Returns to Community College

    ERIC Educational Resources Information Center

    Agan, Amanda Yvonne

    2013-01-01

    Almost half of postsecondary students are currently enrolled in community colleges. These institutions imply that even amongst students with the same degree outcome there is considerable heterogeneity in the path taken to get there. I estimate the life-cycle private and social returns to the different postsecondary paths and sequential decisions…

  14. Analysing Enterprise Returns on Training.

    ERIC Educational Resources Information Center

    Moy, Janelle; McDonald, Rod

    Recent Australian and overseas studies on evaluation of enterprises' return on training investment (ROTI) were reviewed to identify key issues in encouraging increased evaluation of training benefits by enterprises and successful approaches that may inform future "enterprise-friendly" studies of ROTI. It was concluded that more practical,…

  15. Phobos Sample Return: Next Approach

    NASA Astrophysics Data System (ADS)

    Zelenyi, Lev; Martynov, Maxim; Zakharov, Alexander; Korablev, Oleg; Ivanov, Alexey; Karabadzak, George

    The Martian moons still remain a mystery after numerous studies by Mars orbiting spacecraft. Their study cover three major topics related to (1) Solar system in general (formation and evolution, origin of planetary satellites, origin and evolution of life); (2) small bodies (captured asteroid, or remnants of Mars formation, or reaccreted Mars ejecta); (3) Mars (formation and evolution of Mars; Mars ejecta at the satellites). As reviewed by Galimov [2010] most of the above questions require the sample return from the Martian moon, while some (e.g. the characterization of the organic matter) could be also answered by in situ experiments. There is the possibility to obtain the sample of Mars material by sampling Phobos: following to Chappaz et al. [2012] a 200-g sample could contain 10-7 g of Mars surface material launched during the past 1 mln years, or 5*10-5 g of Mars material launched during the past 10 mln years, or 5*1010 individual particles from Mars, quantities suitable for accurate laboratory analyses. The studies of Phobos have been of high priority in the Russian program on planetary research for many years. Phobos-88 mission consisted of two spacecraft (Phobos-1, Phobos-2) and aimed the approach to Phobos at 50 m and remote studies, and also the release of small landers (long-living stations DAS). This mission implemented the program incompletely. It was returned information about the Martian environment and atmosphere. The next profect Phobos Sample Return (Phobos-Grunt) initially planned in early 2000 has been delayed several times owing to budget difficulties; the spacecraft failed to leave NEO in 2011. The recovery of the science goals of this mission and the delivery of the samples of Phobos to Earth remain of highest priority for Russian scientific community. The next Phobos SR mission named Boomerang was postponed following the ExoMars cooperation, but is considered the next in the line of planetary exploration, suitable for launch around 2022. A

  16. Vocational Agriculture Computer Handbook.

    ERIC Educational Resources Information Center

    Kentucky State Dept. of Education, Frankfort.

    This document is a catalog of reviews of computer software suitable for use in vocational agriculture programs. The reviews were made by vocational agriculture teachers in Kentucky. The reviews cover software on the following topics: farm management, crop production, livestock production, horticulture, agricultural mechanics, general agriculture,…

  17. Handbook of Agricultural Geophysics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Geophysical methods continue to show great promise for use in agriculture. The term “agricultural geophysics” denotes a subdiscipline of geophysics that is focused only on agricultural applications. The Handbook of Agricultural Geophysics was compiled to include a comprehensive overview of the geoph...

  18. AGRICULTURAL CHEMICAL USAGE DATA

    EPA Science Inventory

    This report, which summarizes the use of agricultural chemicals is issued by the National Agricultural Statistics Service (NASS) as part of its series on Agricultural Chemical Usage. Other publications in the series present statistics for on-farm agricultural chemical usage for f...

  19. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint return after filing separate return. 1... filing separate return. (a) In general. (1) Where an individual has filed a separate return for a taxable... separate return of either spouse are to be taken into account in determining the extent to which the...

  20. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Joint return after filing separate return. 1.6013-2 Section 1.6013-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return after filing separate return. (a) In general....

  1. 26 CFR 20.6075-1 - Returns; time for filing estate tax return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 14 2011-04-01 2010-04-01 true Returns; time for filing estate tax return. 20.6075-1 Section 20.6075-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Administration § 20.6075-1 Returns; time for filing estate tax return. The estate tax return required by...

  2. 26 CFR 20.6075-1 - Returns; time for filing estate tax return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Returns; time for filing estate tax return. 20.6075-1 Section 20.6075-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Administration § 20.6075-1 Returns; time for filing estate tax return. The estate tax return required by...

  3. Return to nursing home investment: Issues for public policy

    PubMed Central

    Baldwin, Carliss Y.; Bishop, Christine E.

    1984-01-01

    Because Government policy does much to determine the return available to nursing home investment, the profitability of the nursing home industry has been a subject of controversy since Government agencies began paying a large portion of the Nation's nursing home bill. Controversy appears at several levels. First is the rather narrow concern, often conceived in accounting terms, of the appropriate reimbursement of capital-related expense under Medicaid and Medicare. Second is the concern about how return to capital affects the flow of investment into nursing homes, leading either to inadequate access to care or to over-capacity. Third is the concern about how-sources of return to nursing home investment affect the pattern of nursing home ownership and the amount of equity held by owners since the pattern of ownership and amount of equity have been linked to quality of care. PMID:10310945

  4. Landscape irrigation management for maintaining an aquifer and economic returns.

    PubMed

    Kovacs, Kent Forrest; Mancini, Mattia; West, Grant

    2015-09-01

    Expanding irrigated agriculture and dryer climatic conditions has led to large-scale withdrawals of groundwater and the decline in shallow aquifers. Policy makers must wrestle with the challenge of maintaining economic growth while conserving the groundwater resource. A spatially explicit landscape level model analyzes consequences of optimally chosen crop mix patterns on an aquifer and economic returns. The model of the groundwater use incorporates irrigation needs of the crops grown, initial aquifer thickness, hydro-conductivity of the aquifer, and distance to surrounding grid cells. The economic model incorporates the site specific yield, crop mix, and irrigation practice investments to predict economic returns. A tradeoff occurs between the volume of the aquifer and economic returns due to groundwater withdrawal for irrigation, but the farm's ability to grow profitable lower irrigation crops dampens the intensity of this tradeoff. Allowing for multiple unconventional irrigation practices that are yield increasing and water conserving significantly increases the economic returns of a given crop mix while maintaining the aquifer. PMID:26144558

  5. Asteroid Return Mission Feasibility Study

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Gershman, Robert; Landau, Damon; Polk, James; Porter, Chris; Yeomans, Don; Allen, Carlton; Williams, Willie; Asphaug, Erik

    2011-01-01

    This paper describes an investigation into the technological feasibility of finding, characterizing, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the International Space Station (ISS) for scientific investigation, evaluation of its resource potential, determination of its internal structure and other aspects important for planetary defense activities, and to serve as a testbed for human operations in the vicinity of an asteroid. Reasonable projections suggest that several dozen candidates NEAs in the size range of interest (approximately 2-m diameter) will be known before the end of the decade from which a suitable target could be selected. The conceptual mission objective is to return an approximately 10,000-kg asteroid to the ISS in a total flight time of approximately 5 years using a single Evolved Expendable Launch Vehicle. Preliminary calculations indicate that this could be accomplished using a solar electric propulsion (SEP) system with high-power Hall thrusters and a maximum power into the propulsion system of approximately 40 kW. The SEP system would be used to provide all of the post-launch delta V. The asteroid would have an unrestricted Earth return Planetary Protection categorization, and would be curated at the ISS where numerous scientific and resource utilization experiments would be conducted. Asteroid material brought to the ground would be curated at the NASA Johnson Space Center. This preliminary study identified several areas where additional work is required, but no show stoppers were identified for the approach that would return an entire 10,000-kg asteroid to the ISS in a mission that could be launched by the end of this decade.

  6. Comet nucleus sample return mission

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A comet nucleus sample return mission in terms of its relevant science objectives, candidate mission concepts, key design/technology requirements, and programmatic issues is discussed. The primary objective was to collect a sample of undisturbed comet material from beneath the surface of an active comet and to preserve its chemical and, if possible, its physical integrity and return it to Earth in a minimally altered state. The secondary objectives are to: (1) characterize the comet to a level consistent with a rendezvous mission; (2) monitor the comet dynamics through perihelion and aphelion with a long lived lander; and (3) determine the subsurface properties of the nucleus in an area local to the sampled core. A set of candidate comets is discussed. The hazards which the spacecraft would encounter in the vicinity of the comet are also discussed. The encounter strategy, the sampling hardware, the thermal control of the pristine comet material during the return to Earth, and the flight performance of various spacecraft systems and the cost estimates of such a mission are presented.

  7. Tick size and stock returns

    NASA Astrophysics Data System (ADS)

    Onnela, Jukka-Pekka; Töyli, Juuso; Kaski, Kimmo

    2009-02-01

    Tick size is an important aspect of the micro-structural level organization of financial markets. It is the smallest institutionally allowed price increment, has a direct bearing on the bid-ask spread, influences the strategy of trading order placement in electronic markets, affects the price formation mechanism, and appears to be related to the long-term memory of volatility clustering. In this paper we investigate the impact of tick size on stock returns. We start with a simple simulation to demonstrate how continuous returns become distorted after confining the price to a discrete grid governed by the tick size. We then move on to a novel experimental set-up that combines decimalization pilot programs and cross-listed stocks in New York and Toronto. This allows us to observe a set of stocks traded simultaneously under two different ticks while holding all security-specific characteristics fixed. We then study the normality of the return distributions and carry out fits to the chosen distribution models. Our empirical findings are somewhat mixed and in some cases appear to challenge the simulation results.

  8. The Mars Sample Return Project.

    PubMed

    O'Neil, W J; Cazaux, C

    2000-01-01

    The Mars Sample Return (MSR) Project is underway. A 2003 mission to be launched on a Delta III Class vehicle and a 2005 mission launched on an Ariane 5 will culminate in carefully selected Mars samples arriving on Earth in 2008. NASA is the lead agency and will provide the Mars landed elements, namely, landers, rovers, and Mars ascent vehicles (MAVs). The French Space Agency CNES is the largest international partner and will provide for the joint NASA/CNES 2005 Mission the Ariane 5 launch and the Earth Return Mars Orbiter that will capture the sample canisters from the Mars parking orbits the MAVs place them in. The sample canisters will be returned to Earth aboard the CNES Orbiter in the Earth Entry Vehicles provided by NASA. Other national space agencies are also expected to participate in substantial roles. Italy is planning to provide a drill that will operate from the Landers to provide subsurface samples. Other experiments in addition to the MSR payload will also be carried on the Landers. This paper will present the current status of the design of the MSR missions and flight articles. PMID:11708368

  9. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 18 2014-04-01 2014-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  10. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 18 2013-04-01 2013-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  11. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 18 2012-04-01 2012-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  12. 26 CFR 301.6103(c)-1 - Disclosure of returns and return information to designee of taxpayer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 18 2011-04-01 2011-04-01 false Disclosure of returns and return information to... and Returns Returns and Records § 301.6103(c)-1 Disclosure of returns and return information to... Service to disclose a taxpayer's return or return information to such person or persons as the...

  13. Agricultural Aircraft for Site-Specific Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural aircraft provide a convenient platform to aid in precision agriculture, in which pesticide, fertilizer or other field inputs are applied only where they are needed. This saves on chemical and farm resources, and reduces environmental loading. Remote sensing is used to spot areas of the ...

  14. Agricultural Chartbook 1988. Agriculture Handbook No. 673.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    These charts present an overview of the current economic health of American agriculture. The charts move from the national and international arenas to farm economic health measures and crop and livestock trends. A small amount of descriptive narrative accompanies most of the charts. Charts depicting the economic picture of U.S. agriculture include…

  15. 1986 Agricultural Chartbook. Agriculture Handbook No. 663.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    This book contains 310 charts, tables, and graphs containing statistical information about agriculture-related commodities and services, primarily in the United States, in 1986. The book is organized in seven sections that cover the following topics: (1) the farm (farm income, farm population, farm workers, food and fiber system, agriculture and…

  16. Comet coma sample return via Giotto II

    NASA Technical Reports Server (NTRS)

    Tsou, P.; Brownlee, D. E.; Albee, A. L.

    1985-01-01

    A comet coma sample return is possible with a low-cost flyby mission. Collecting coma materials and returning them to earth can be accomplished in a free-return trajectory. Intact capture of coma dust, preserving the cometary dust mineralogy, is possible at low encounter speeds. Samples from a known cometary source can then be compared with the wealth of information on meteorites and interplanetary dust. Sample return via Giotto II is a unique, low-cost NASA/ESA cooperative opportunity. With ESA providing the Giotto spacecraft and payload and NASA the sample return capability, first-class science can be accomplished at a very low cost for both NASA and ESA. This paper focuses on the sample return aspects, including sample return objectives, sample collection techniques, experimental work to verify collection concepts, and some of the characteristics of the cometary targets for sample return.

  17. FGD gypsum's place in American agriculture

    SciTech Connect

    Haynes, C.

    2007-07-01

    Surface cracks and soil clumps form when saline-sodic, high-clay soil dries out. Treatment with FGD gypsum and irrigation water flowing into these cracks leaches salts until the aggregates swell and the cracks close up. The article describes research projects to develop agricultural uses of FGD gypsum from coal-fired power plants that have been conducted by university researchers and USDA-Agricultural Research Service scientists.

  18. Sustainable intensification in agricultural systems

    PubMed Central

    Pretty, Jules; Bharucha, Zareen Pervez

    2014-01-01

    Background Agricultural systems are amended ecosystems with a variety of properties. Modern agroecosystems have tended towards high through-flow systems, with energy supplied by fossil fuels directed out of the system (either deliberately for harvests or accidentally through side effects). In the coming decades, resource constraints over water, soil, biodiversity and land will affect agricultural systems. Sustainable agroecosystems are those tending to have a positive impact on natural, social and human capital, while unsustainable systems feed back to deplete these assets, leaving fewer for the future. Sustainable intensification (SI) is defined as a process or system where agricultural yields are increased without adverse environmental impact and without the conversion of additional non-agricultural land. The concept does not articulate or privilege any particular vision or method of agricultural production. Rather, it emphasizes ends rather than means, and does not pre-determine technologies, species mix or particular design components. The combination of the terms ‘sustainable’ and ‘intensification’ is an attempt to indicate that desirable outcomes around both more food and improved environmental goods and services could be achieved by a variety of means. Nonetheless, it remains controversial to some. Scope and Conclusions This review analyses recent evidence of the impacts of SI in both developing and industrialized countries, and demonstrates that both yield and natural capital dividends can occur. The review begins with analysis of the emergence of combined agricultural–environmental systems, the environmental and social outcomes of recent agricultural revolutions, and analyses the challenges for food production this century as populations grow and consumption patterns change. Emergent criticisms are highlighted, and the positive impacts of SI on food outputs and renewable capital assets detailed. It concludes with observations on policies and

  19. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  20. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  1. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  2. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  3. 5 CFR 1650.5 - Returned funds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Returned funds. 1650.5 Section 1650.5 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN General § 1650.5 Returned funds. If a withdrawal is returned as undeliverable, the TSP...

  4. 50 CFR 12.51 - Return procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Return procedure. 12.51 Section 12.51 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR TAKING... SEIZURE AND FORFEITURE PROCEDURES Return of Property § 12.51 Return procedure. If, at the conclusion...

  5. 21 CFR 203.23 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Returns. 203.23 Section 203.23 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL PRESCRIPTION DRUG MARKETING Sales Restrictions § 203.23 Returns. The return of a prescription drug purchased...

  6. Biotechnology Enters Vocational Agriculture.

    ERIC Educational Resources Information Center

    Martin, Robert A.

    1988-01-01

    Points out that the agriculture industry is changing and that vocational agriculture students must learn more science than before to be prepared. Iowa formed groups of educators and business representatives to advise on which curricula should be funded. (JOW)

  7. Strategies for Agriculture.

    ERIC Educational Resources Information Center

    Crosson, Pierre R.; Rosenberg, Norman J.

    1989-01-01

    Discusses the change of agricultural methods with human population growth. Describes the trends of world food production, changes in farmland, use of fertilizer, and 13 agricultural research institutions. Lists 5 references for further reading. (YP)

  8. Traditional Agriculture and Permaculture.

    ERIC Educational Resources Information Center

    Pierce, Dick

    1997-01-01

    Discusses benefits of combining traditional agricultural techniques with the concepts of "permaculture," a framework for revitalizing traditions, culture, and spirituality. Describes school, college, and community projects that have assisted American Indian communities in revitalizing sustainable agricultural practices that incorporate cultural…

  9. 9 CFR 355.22 - Designation of place of receipt of returned products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Designation of place of receipt of returned products. 355.22 Section 355.22 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION...

  10. Mars 2005 Sample Return Workshop

    NASA Technical Reports Server (NTRS)

    Gulick, V. C. (Editor)

    1997-01-01

    Convened at the request of Dr. Jurgen Rahe of the NASA Office of Space Science, the purpose of this workshop was to reexamine the science issues that will determine how an optimum sample return mission would be carried out in 2005 given the new context that has emerged for Mars exploration since the last such workshop was held (in 1987). The results and summary of discussion that took place at the meeting are contained in this volume. The community was invited to participate in the preparation of the final written report by browsing through the agenda and reading the text and viewgraphs provided by workshop participants and submitting comments for that section.

  11. Data link and return link

    NASA Astrophysics Data System (ADS)

    Meuron, Bruce R.; Lyons, Joseph B., Jr.

    1991-05-01

    This invention relates to a data coder, code searching mechanism, data decoder, and range computer for a missile wherein the missile receiver is able to discriminate between the real signals and jamming signals. The system provides discrimination in aircraft receiver systems for the return synchronization signal. This is accomplished by utilizing a random code generator wherein the command data signals modulate the code train which in turn modulates the RF carrier. The missile contains a second code generator with a code searching mechanism which synchronizes the second code generator with the first generator. The comparison of the second code generator signal with the received signal produces the command signal as an output.

  12. Mars rover sample return missions

    NASA Technical Reports Server (NTRS)

    Cunningham, Glenn E.; Rea, Donald G.; Pivirotto, Donna; Kwok, Johnny; Craig, Mark K.

    1988-01-01

    An important intermediate step in the path to human exploration of Mars is the accomplishment of a mission which lands an unmanned rover on the Martian surface, selects and collects various samples of the terrain and atmosphere, and returns them to earth for analysis. Such a mission is being developed under the management of NASA's JPL and the Johnson Space Center. The concepts for a wide range of rover capabilities are studied and an assessment of the driving technological developments required to implement these capabilities is made.

  13. Return to Flight Task Group

    NASA Technical Reports Server (NTRS)

    2005-01-01

    It has been 29 months since Columbia was lost over East Texas in February 2003. Seven months after the accident, the Columbia Accident Investigation Board (CAIB) released the first volume of its final report, citing a variety of technical, managerial, and cultural issues within NASA and the Space Shuttle Program. To their credit, NASA offered few excuses, embraced the report, and set about correcting the deficiencies noted by the accident board. Of the 29 recommendations issued by the CAIB, 15 were deemed critical enough that the accident board believed they should be implemented prior to returning the Space Shuttle to flight. Some of these recommendations were relatively easy, most were straightforward, a few bordered on the impossible, and others were largely overcome by events, particularly the decision by the President to retire the Space Shuttle by 2010. The Return to Flight Task Group (RTF TG, or simply, the Task Group) was chartered by the NASA Administrator in July 2003 to provide an independent assessment of the implementation of the 15 CAIB return-to-flight recommendations. An important observation must be stated up-front: neither the CAIB nor the RTF TG believes that all risk can be eliminated from Space Shuttle operations; nor do we believe that the Space Shuttle is inherently unsafe. What the CAIB and RTF TG do believe, however, is that NASA and the American public need to understand the risks associated with space travel, and that NASA must make every reasonable effort to minimize such risk. Since the release of the CAIB report, NASA and the Space Shuttle Program expended enormous effort and resources toward correcting the causes of the accident and preparing to fly again. Relative to the 15 specific recommendations that the CAIB indicated should be implemented prior to returning to flight, NASA has met or exceeded most of them the Task Group believes that NASA met the intent of the CAIB for 12 of these recommendations. The remaining three

  14. GUIDELINES FOR VOCATIONAL AGRICULTURE.

    ERIC Educational Resources Information Center

    Maryland State Dept. of Education, Baltimore.

    AREAS OF TRAINING WHICH ARE OFFERED IN THE VOCATIONAL AGRICULTURE DEPARTMENTS OF MARYLAND ARE PRESENTED IN THIS DOCUMENT. AGRICULTURE TEACHERS AND ADVISORY GROUPS MAY SELECT AREAS OF TRAINING FROM THE TOPICAL OUTLINE OR ADD NEW AREAS AS NEEDED IN THE LOCAL INSTRUCTIONAL PROGRAM. PHILOSOPHY, SPECIFIC OBJECTIVES, GROUPS SERVED, AGRICULTURAL TRENDS…

  15. Biotechnology and Agriculture.

    ERIC Educational Resources Information Center

    Kenney, Martin

    Even at this early date in the application of biotechnology to agriculture, it is clear that agriculture may provide the largest market for new or less expensive biotechnologically manufactured products. The chemical and pharmaceutical industries that hold important positions in agricultural inputs are consolidating their positions by purchasing…

  16. Connecticut Vocational Agriculture Curriculum.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Bureau of Vocational Services.

    Designed for use in the Connecticut Regional Vocational Agriculture Centers, this curriculum provides exploratory and specialization units for four major areas of agriculture. These are Agriculture Mechanics, Animal Science, Natural Resources, and Plant Science. The exploratory units are required for grades 9 and 10, while the specialization units…

  17. Agriculture, Environmental Education Guide.

    ERIC Educational Resources Information Center

    Project I-C-E, Green Bay, WI.

    This agriculture guide, for use at the secondary level, is one of a series of guides, K-12, which were developed by teachers to help introduce environmental education into the total curriculum. Environmental problems are present in every community where agriculture education is offered, and therefore many agriculture teachers have included some…

  18. Agricultural Structures, Volume II.

    ERIC Educational Resources Information Center

    Linhardt, Richard E.; Burhoe, Steve

    This guide to a curriculum unit in agricultural structures is designed to expand the curriculum materials available in vocational agriculture in Missouri. It and Agricultural Structures I (see note) provide reference materials to systematize the curriculum. The six units cover working with concrete (19 lessons, 2 laboratory exercises), drawing and…

  19. Dutch Agricultural Education.

    ERIC Educational Resources Information Center

    Netherlands Ministry of Agriculture and Fisheries, The Hauge.

    Agricultural Education in the Netherlands is categorized as Scientific, Higher Secondary, Middle Secondary, and Lower Secondary. Scientific education is given at the agricultural university which has a 6- or 7-year curriculum. Higher secondary education is given at agricultural and horticultural colleges with a 3- to 4-year curriculum. Middle…

  20. Agriculture Business and Management.

    ERIC Educational Resources Information Center

    Seperich, George; And Others

    This curriculum guide is intended for vocational agriculture teachers who deliver agricultural business and management programs at the secondary or postsecondary level. It is based on the Arizona validated occupational competencies and tasks for management and supervisory positions in agricultural business. The competency/skill and task list…

  1. Information for Agricultural Development.

    ERIC Educational Resources Information Center

    Kaungamno, E. E.

    This paper describes the major international agricultural information services, sources, and systems; outlines the existing information situation in Tanzania as it relates to problems of agricultural development; and reviews the improvements in information provision resources required to support the process of agricultural development in Tanzania.…

  2. Chapter 3: Cropland Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2013, cropland agriculture resulted in total emissions of approximately 209 MMT CO2 eq. of greenhouse gases (GHG). Cropland agriculture is responsible for almost half (46%) of all emissions from the agricultural sector. Nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) emissions from c...

  3. Return to Play After Lumbar Spine Surgery.

    PubMed

    Cook, Ralph W; Hsu, Wellington K

    2016-10-01

    Surgical management of lumbar spine conditions can produce excellent outcomes in athletes. Microdiscectomy for lumbar disc herniation has favorable outcomes; most athletes return to play at preoperative performance levels. Direct pars repair is successful in younger athletes, with high rates of return to play for a variety of fixation techniques. Fusion in athletes with scoliosis is a negative predictor. There are few evidence-based return to play criteria. Athletes should demonstrate full resolution of symptoms and flexibility, endurance, and strength before returning to play. Deciding when to return an athlete to sport depends on particular injury sustained, sport, and individual factors. PMID:27543402

  4. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of the excess. (ii) If any part of such excess is attributable to fraud with intent to evade tax at... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return... which the tax based on the joint return has been paid. (2) If a joint return is made under section...

  5. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of the excess. (ii) If any part of such excess is attributable to fraud with intent to evade tax at... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return... which the tax based on the joint return has been paid. (2) If a joint return is made under section...

  6. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of the excess. (ii) If any part of such excess is attributable to fraud with intent to evade tax at... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-2 Joint return... which the tax based on the joint return has been paid. (2) If a joint return is made under section...

  7. 12 CFR 210.12 - Return of cash items and handling of returned checks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... accounting entries) subject to this subpart and to the Reserve Banks' operating circulars. (2) Warranties for... the returned check, in paper or electronic form, for forward collection or return. (3) Warranties for all returned checks that are electronic items. A paying bank or returning bank that sends a...

  8. Removal of Nitrogen and Pathogens in Agricultural or Urban Channles using Engineered Streambeds

    NASA Astrophysics Data System (ADS)

    McCray, J. E.; Herzog, S.; Higgins, C. P.

    2015-12-01

    Treating non-point source pollution is one of our greatest challenges in environmental hydrology. Previous efforts in agricultural or urban settings have focused on removing sources or implementing distributed best management practices (BMPs) throughout a watershed. However, for stream pollution, the most efficient point of treatment would be within the stream itself, which integrates flows from the entire watershed. Engineered streambed modifications in urban or agricultural streams and constructed channels have the potential to mitigate nonpoint source pollution. Geomedia designed to treat water pollutants and achieve an optimal residence time via hydraulic conductivity modifications are termed biohydrochemical enhancement structures for stream water treatment (BEST). BEST modules can efficiently drive interchange, attenuating nutrients and pathogens (and can be designed to remove other pollutants such as phosphorus, metals or trace organics). Numerical models, combined with data from bench-top and 2D experiments, demonstrate effective contaminant removal potential for practical applications. Nitrogen and pathogens could be attenuated within a series of BEST on the order of 50 m of stream length, and at a favorable cost compared to traditional BMPs, suggesting that BEST could be an effective best management practice for constructed stormwater channels (particularly outlets of detention ponds) or channels carrying irrigation return flows. New results from a constructed stream demonstrate the real-world applicability of the BEST system.

  9. Investigation of the effects of returning electrons on klystron performance

    NASA Astrophysics Data System (ADS)

    Roybal, William Thomas

    The klystron, as part of an RF distribution system for an accelerator, is one of the most important components contributing to the cost, reliability, and longevity of the overall system. Operating cost is one of the primary concerns for klystrons. Achieving high direct current (DC) to radio frequency (RF) conversion efficiency, free of instabilities is very important. There is uncertainty concerning the effects of returning electrons within the klystron and the impact that they have on klystron performance. The effects of reverse traveling electrons on klystron performance, such as efficiency, are poorly defined. Classical and even modern klystron design avoids the consideration of return electrons, and thus the effects have not been numerically analyzed and quantified. A better understanding of the electron beam-to-RF conversion process and the effects of return electrons within the klystron output circuit is needed. Accurate klystron modeling and simulation of return electron effects are required to better understand the implications of the problem. This analysis identifies the influence that returning electrons have on the overall beam dynamics and self-consistent cavity voltages. Closer examination of the harmonic content within the reverse beam current, along with comparison to the nominal klystron design, reveals the effects that reverse flowing electrons can have on klystron performance and design. The results of this work include a description of the electron beam dynamics for a beam decelerated in the output cavity, with separation occurring between forward and reverse electrons. Varying the output parameter of the klystron causes an unexpected response in return current quantity and bunching quality, yielding periodic correlations and responses to two-stream interaction.

  10. The dynamics of health and return migration.

    PubMed

    Davies, Anita A; Borland, Rosilyne M; Blake, Carolyn; West, Haley E

    2011-06-01

    The increasing importance and complexity of migration globally also implies a global increase in return migration, and thus an increased interest in the health of returning migrants. The health of returning migrants is impacted by the cumulative exposure to social determinants and risk factors of health during the migration process, during the return movement, and following return. Circular migration often occurs among the diaspora, which can result in the transfer of knowledge and skills that contribute to development, including health system strengthening. Migrants with dual nationality often return to countries with better health services than their country of origin when they are sick and can not get care at home. To maintain and improve the health of returning migrants, multi-sectoral policies at global and national levels should facilitate access to appropriate and equitable health services, social services, and continuity of care across and within borders. PMID:21738448

  11. Supervised Occupational Experience Programs in Vocational Agriculture. Bulletin No. 705.

    ERIC Educational Resources Information Center

    Pals, Douglas A.; Slocombe, John W.

    A 1985 study examined the quality and quantity of Idaho supervised occupational experience (SOE) programs as perceived by a sample of 38 instructors and 1,198 students who returned questionnaires sent to all vocational agriculture students and teachers throughout the state. Data on the value of SOE as perceived by parents, employers, and…

  12. [Agricultural migration has changed face].

    PubMed

    Ouedraogo, D

    1991-04-01

    decertification of the Sahel. Rural population transfers sponsored by the government have also entailed high costs and met with only partial success. Local populations displaced by dams, large reforestation projects, and other large projects have not always been compensated and relocated adequately. The more significant type of government population transfer program involves relocation at greater distances of residents of relatively poor and overpopulated regions to managed zones where agricultural intensification makes better returns and incomes possible. Large resettlement projects based on improved agricultural techniques including irrigation have yielded disappointing results since the 1960s due to high cost, inadequate management of irrigation, and difficult recruitment of settlers. Results of these projects should be kept in mind when plan for rural population redistribution are made. PMID:12343343

  13. The economic returns to investment in project-related training: Some empirical evidence

    NASA Astrophysics Data System (ADS)

    Mingat, Alain; Tan, Jee-Peng

    1988-06-01

    This paper assesses the efficiency of investing in project related training (PRT) to overcome skill deficiencies that are identified in project populations. Data for the analysis comes from 115 World Bank agricultural and non-agricultural projects (transportation, urban, chemicals, and manufacturing). Unlike most other studies, this paper does not rely on earnings data to derive the relevant rates of return, using instead project success as the outcome measure. The results indicate that PRT yields high economic returns in both agricultural and non-agricultural projects, even under conservative assumptions. However, they also underline that training investment achieves high returns only when the educational base of a country is sufficiently developed. In the absence of this condition, PRT — as it is currently designed and implemented — is an uneconomic investment. The results suggest the following implications: (a) expand PRT investment, particularly in agriculture projects, when a sufficiently high proportion of the population is literate; (b) in countries with a weak educational base, make significant efforts to adapt the design and management of PRT to overcome effectively the existing skill deficiencies in the project population; and (c) in countries where education is poorly developed, overall long run development strategy should probably stress investment in basic education so as to create the conditions for other investments to achieve economic protitability.

  14. Performance Improvement of a Return Channel in a Multistage Centrifugal Compressor Using Multiobjective Optimization.

    PubMed

    Nishida, Yoshifumi; Kobayashi, Hiromi; Nishida, Hideo; Sugimura, Kazuyuki

    2013-05-01

    The effect of the design parameters of a return channel on the performance of a multistage centrifugal compressor was numerically investigated, and the shape of the return channel was optimized using a multiobjective optimization method based on a genetic algorithm to improve the performance of the centrifugal compressor. The results of sensitivity analysis using Latin hypercube sampling suggested that the inlet-to-outlet area ratio of the return vane affected the total pressure loss in the return channel, and that the inlet-to-outlet radius ratio of the return vane affected the outlet flow angle from the return vane. Moreover, this analysis suggested that the number of return vanes affected both the loss and the flow angle at the outlet. As a result of optimization, the number of return vane was increased from 14 to 22 and the area ratio was decreased from 0.71 to 0.66. The radius ratio was also decreased from 2.1 to 2.0. Performance tests on a centrifugal compressor with two return channels (the original design and optimized design) were carried out using two-stage test apparatus. The measured flow distribution exhibited a swirl flow in the center region and a reversed swirl flow near the hub and shroud sides. The exit flow of the optimized design was more uniform than that of the original design. For the optimized design, the overall two-stage efficiency and pressure coefficient were increased by 0.7% and 1.5%, respectively. Moreover, the second-stage efficiency and pressure coefficient were respectively increased by 1.0% and 3.2%. It is considered that the increase in the second-stage efficiency was caused by the increased uniformity of the flow, and the rise in the pressure coefficient was caused by a decrease in the residual swirl flow. It was thus concluded from the numerical and experimental results that the optimized return channel improved the performance of the multistage centrifugal compressor. PMID:24891759

  15. Modeling agriculture in the Community Land Model

    NASA Astrophysics Data System (ADS)

    Drewniak, B.; Song, J.; Prell, J.; Kotamarthi, V. R.; Jacob, R.

    2012-12-01

    The potential impact of climate change on agriculture is uncertain. In addition, agriculture could influence above- and below-ground carbon storage. Development of models that represent agriculture is necessary to address these impacts. We have developed an approach to integrate agriculture representations for three crop types - maize, soybean, and spring wheat - into the coupled carbon-nitrogen version of the Community Land Model (CLM), to help address these questions. Here we present the new model, CLM-Crop, validated against observations from two AmeriFlux sites in the United States, planted with maize and soybean. Seasonal carbon fluxes compared well with field measurements. CLM-Crop yields were comparable with observations in some regions, although the generality of the crop model and its lack of technology and irrigation made direct comparison difficult. CLM-Crop was compared against the standard CLM3.5, which simulates crops as grass. The comparison showed improvement in gross primary productivity in regions where crops are the dominant vegetation cover. Crop yields and productivity were negatively correlated with temperature and positively correlated with precipitation. In case studies with the new crop model looking at impacts of residue management and planting date on crop yield, we found that increased residue returned to the litter pool increased crop yield, while reduced residue returns resulted in yield decreases. Using climate controls to signal planting date caused different responses in different crops. Maize and soybean had opposite reactions: when low temperature threshold resulted in early planting, maize responded with a loss of yield, but soybean yields increased. Our improvements in CLM demonstrate a new capability in the model - simulating agriculture in a realistic way, complete with fertilizer and residue management practices. Results are encouraging, with improved representation of human influences on the land surface and the potentially

  16. Modeling agriculture in the Community Land Model

    NASA Astrophysics Data System (ADS)

    Drewniak, B.; Song, J.; Prell, J.; Kotamarthi, V. R.; Jacob, R.

    2013-04-01

    The potential impact of climate change on agriculture is uncertain. In addition, agriculture could influence above- and below-ground carbon storage. Development of models that represent agriculture is necessary to address these impacts. We have developed an approach to integrate agriculture representations for three crop types - maize, soybean, and spring wheat - into the coupled carbon-nitrogen version of the Community Land Model (CLM), to help address these questions. Here we present the new model, CLM-Crop, validated against observations from two AmeriFlux sites in the United States, planted with maize and soybean. Seasonal carbon fluxes compared well with field measurements for soybean, but not as well for maize. CLM-Crop yields were comparable with observations in countries such as the United States, Argentina, and China, although the generality of the crop model and its lack of technology and irrigation made direct comparison difficult. CLM-Crop was compared against the standard CLM3.5, which simulates crops as grass. The comparison showed improvement in gross primary productivity in regions where crops are the dominant vegetation cover. Crop yields and productivity were negatively correlated with temperature and positively correlated with precipitation, in agreement with other modeling studies. In case studies with the new crop model looking at impacts of residue management and planting date on crop yield, we found that increased residue returned to the litter pool increased crop yield, while reduced residue returns resulted in yield decreases. Using climate controls to signal planting date caused different responses in different crops. Maize and soybean had opposite reactions: when low temperature threshold resulted in early planting, maize responded with a loss of yield, but soybean yields increased. Our improvements in CLM demonstrate a new capability in the model - simulating agriculture in a realistic way, complete with fertilizer and residue management

  17. Orbiter Atlantis returns to KSC

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Stairs are rolled to the forward opening of the Shuttle Carrier Aircraft -- with its piggyback cargo, the orbiter Atlantis -- after it rolls to a stop at the Shuttle Landing Facility. Atlantis returns home after a 10-month stay in the Palmdale, CA, orbiter processing facility undergoing extensive inspections and modifications. They included several upgrades enabling it to support International Space Station missions, such as adding an external airlock for ISS docking missions and installing thinner, lighter thermal protection blankets for weight reduction which will allow it to haul heavier cargo. The flight from Palmdale included a fueling stop in Ft. Hood, TX, and overnight stay at Ft. Campbell, KY. Atlantis will undergo preparations in the Orbiter Processing Facility at KSC for its planned flight in June 1999.

  18. Sepsis, venous return, and teleology.

    PubMed

    McNeilly, R G

    2014-11-01

    An understanding of heart-circulation interaction is crucial to our ability to guide our patients through an episode of septic shock. Our knowledge has advanced greatly in the last one hundred years. There are, however, certain empirical phenomena that may lead us to question the wisdom of our prevailing treatment algorithm. Three extreme but iatrogenically possible haemodynamic states exist. Firstly, inappropriately low venous return; secondly, overzealous arteriolar constriction; and finally, misguided inotropy and chronotropy. Following an unsuccessful fluid challenge, it would be logical to first set the venous tone, then set the cardiac rate and contractility, and finally set the peripheral vascular resistance. It is hypothesized that a combination of dihydroergotamine, milrinone and esmolol should be superior to a combination of noradrenaline and dobutamine for surviving sepsis. PMID:25245463

  19. Partial Return Yoke for MICE

    SciTech Connect

    Witte H.; Plate, S

    2013-05-03

    The international Muon Ionization Cooling Experiment (MICE) is a large scale experiment which is presently assembled at the Rutherford Appleton Laboratory in Didcot, UK. The purpose of MICE is to demonstrate the concept of ionization cooling experimentally. Ionization cooling is an important accelerator concept which will be essential for future HEP experiments such as a potential Muon Collider or a Neutrino Factory. The MICE experiment will house up to 18 superconducting solenoids, all of which produce a substantial amount of magnetic flux. Recently it was realized that this magnetic flux leads to a considerable stray magnetic field in the MICE hall. This is a concern as technical equipment in the MICE hall may may be compromised by this. In July 2012 a concept called partial return yoke was presented to the MICE community, which reduces the stray field in the MICE hall to a safe level. This report summarizes the general concept, engineering considerations and the expected shielding performance.

  20. 76 FR 65158 - Agricultural Career and Employment Grants Program or “ACE”

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ...To improve the supply of skilled agricultural workers and bring greater stability to the workforce in this sector through provision of services specifically designed to assist farmworkers in securing, retaining, upgrading or returning from an agricultural job. The intended outcomes are that, as a result of the services to be provided, farmers will have access to a more skilled pool of workers......

  1. An assessment of flow data from Klamath River sites between Link River Dam and Keno Dam, south-central Oregon

    USGS Publications Warehouse

    Risley, John C.; Hess, Glen W.; Fisher, Bruce J.

    2006-01-01

    Records of diversion and return flows for water years 1961?2004 along a reach of the Klamath River between Link River and Keno Dams in south-central Oregon were evaluated to determine the cause of a water-balance inconsistency in the hydrologic data. The data indicated that the reach was losing flow in the 1960s and 1970s and gaining flow in the 1980s and 1990s. The absolute mean annual net water-balance difference in flows between the first and second half of the 44-year period (1961-2004) was approximately 103,000 acre-feet per year (acre-ft/yr). The quality of the diversion and return-flow records used in the water balance was evaluated using U.S. Geological Survey (USGS) criteria for accuracy. With the exception of the USGS Klamath River at Keno record, which was rated as 'good' or 'excellent,' the eight other flow records, all from non-USGS flow-measurement sites, were rated as 'poor' by USGS standards due to insufficient data-collection documentation and a lack of direct discharge measurements to verify the rating curves. The record for the Link River site, the most upstream in the study area, included both river and westside power canal flows. Because of rating curve biases, the river flows might have been overestimated by 25,000 acre-ft/yr on average from water years 1961 to 1982 and underestimated by 7,000 acre-ft/yr on average from water years 1983 to 2004. For water years 1984-2004, westside power canal flows might have been underestimated by 11,000 acre-ft/yr. Some diversion and return flows (for mostly agricultural, industrial, and urban use) along the Klamath River study reach, not measured continuously and not included in the water-balance equation, also were evaluated. However, the sum of these diversion and return flows was insufficient to explain the water-balance inconsistency. The possibility that ground-water levels in lands adjacent to the river rose during water years 1961-2004 and caused an increase in ground-water discharge to the river

  2. Aerothermodynamic Environment Definition for the Genesis Sample Return Capsule

    NASA Technical Reports Server (NTRS)

    Cheatwood, F. McNeil; Merski, N. Ronald, Jr.; Riley, Christopher J.; Mitcheltree, Robert A.

    2001-01-01

    NASA's Genesis sample return mission will be the first to return material from beyond the Earth-Moon system. NASA Langley Research Center supported this mission with aerothermodynamic analyses of the sample return capsule. This paper provides an overview of that effort. The capsule is attached through its forebody to the spacecraft bus. When the attachment is severed prior to Earth entry, forebody cavities remain. The presence of these cavities could dramatically increase the heating environment in their vicinity and downstream. A combination of computational fluid dynamics calculations and wind tunnel phosphor thermography tests were employed to address this issue. These results quantify the heating environment in and around the cavities, and were a factor in the decision to switch forebody heat shield materials. A transition map is developed which predicts that the flow aft of the penetrations will still be laminar at the peak heating point of the trajectory. As the vehicle continues along the trajectory to the peak dynamic pressure point, fully turbulent flow aft of the penetrations could occur. The integrated heat load calculations show that a heat shield sized to the stagnation point levels will be adequate for the predicted environment aft of the penetrations.

  3. Modeling the impacts of regulatory frameworks on self-organization in dryland agricultural systems

    NASA Astrophysics Data System (ADS)

    Gower, D.; Caylor, K. K.; McCord, P. F.; Evans, T. P.

    2015-12-01

    The climatological conditions that characterize dryland environments - high potential evapotranspiration combined with low and variable total rainfall - pose challenges for farmers deciding when and how much to irrigate. These challenges are greater in developing countries where the absence of sufficient storage infrastructure means that irrigation water is sometimes applied to agricultural fields directly from rivers. Because soil moisture and river flow both depend on recent rainfall, high irrigation demand often coincides with low river flow, limiting access to water when it is most needed. These feedbacks can constrain the yield increases expected from irrigation in such settings. Scaled up to the catchment level, irrigation water availability varies spatially as well as temporally. Irrigators in upstream areas of the catchment have first access to river water but rely on a smaller drainage network while those in downstream areas are affected by the opposite conditions. During periods of high rainfall, downstream users have the greatest access to water while upstream users are then favored during drought intervals. In the absence of rules governing water access, these flow dynamics will constrain the distribution of potential agricultural yields within the catchment. A simple numerical model simulating catchment and irrigation processes was constructed in order to better understand how climate and geomorphologic characteristics affect crop yield, economic returns and the spatial distribution of irrigated areas. By assuming a statistically representative river network structure, the model was first used to explore the effect of unregulated irrigation withdrawals on these variables. Multiple water management programs, including withdrawal limits, rotational systems and flow minima, were then simulated and the results compared to the unregulated case. This analysis shows the potential for simple models to provide insight into complex irrigation systems and to make

  4. Sample Returns Missions in the Coming Decade

    NASA Technical Reports Server (NTRS)

    Desai, Prasun N.; Mitcheltree, Robert A.; Cheatwood, F. McNeil

    2000-01-01

    In the coming decade, several missions will attempt to return samples to Earth from varying parts of the solar system. These samples will provide invaluable insight into the conditions present during the early formation of the solar system, and possibly give clues to how life began on Earth. A description of five sample return missions is presented (Stardust, Genesis, Muses-C. Mars Sample Return, and Comet Nucleus Sample Return). An overview of each sample return mission is given, concentrating particularly on the technical challenges posed during the Earth entry, descent, and landing phase of the missions. Each mission faces unique challenges in the design of an Earth entry capsule. The design of the entry capsule must address the aerodynamic, heating, deceleration, landing, and recovery requirements for the safe return of samples to Earth.

  5. Agricultural Occupations Programs Planning Guides

    ERIC Educational Resources Information Center

    Stitt, Thomas R.; And Others

    1977-01-01

    A set of program planning guides that include seven areas (1) Agricultural Production, (2) Agricultural Supplies and Services, (3) Agricultural Mechanics, (4) Agricultural Products, (5) Ornamental Horticulture, (6) Agricultural Resources, and (7) Forestry, were developed and introduced to high school applied biological and agricultural occupations…

  6. Return to sport after ACL reconstruction.

    PubMed

    Harris, Joshua D; Abrams, Geoffrey D; Bach, Bernard R; Williams, Donna; Heidloff, Dave; Bush-Joseph, Charles A; Verma, Nikhil N; Forsythe, Brian; Cole, Brian J

    2014-02-01

    Objective guidelines permitting safe return to sport following anterior cruciate ligament (ACL) reconstruction are infrequently used. The purpose of this study was to determine the published return to sport guidelines following ACL reconstruction in Level I randomized controlled trials. A systematic review was performed using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Level I randomized controlled trials were included if they reported a minimum 2-year follow-up after ACL reconstruction and return to sport criteria. Outcomes analyzed were the timing of initiation of return to sport, follow-up duration, and use of quantitative/qualitative criteria to determine return to sport. Forty-nine studies were included (N=4178; 68% male; mean patient age, 27.5±3.2 years; mean follow-up, 3.0±1.9 years; mean time from injury to reconstruction, 379±321 days). Ninety-six percent of reconstructions used autograft and 87% were single-bundle reconstructions. Lysholm score, single-leg hop, isokinetic strength, and KT-1000 or KT-2000 arthrometer (MEDmetric, San Diego, California) testing were performed in 67%, 31%, 31%, and 82% of studies, respectively. Only 5 studies reported whether patients were able to successfully return to sport. Ninety percent and 65% of studies failed to use objective criteria or any criteria, respectively, to permit return to sport. Description of permission/allowance to return to sport was highly variable and poor. Twenty-four percent of studies failed to report when patients were allowed return to sport without restrictions. Overall, 39%, 45%, and 51% of studies permitted running at 3 months, return to cutting/pivoting sports at 6 months, and return to sport without restrictions at 6 months, respectively. Further research into validated return to sport guidelines is necessary to fill the existing void in contemporary literature and to guide clinical practice. PMID:24679194

  7. Agricultural aviation research

    NASA Technical Reports Server (NTRS)

    Chevalier, H. L. (Compiler); Bouse, L. F. (Compiler)

    1977-01-01

    A compilation of papers, comments, and results is provided during a workshop session. The purpose of the workshop was to review and evaluate the current state of the art of agricultural aviation, to identify and rank potentially productive short and long range research and development areas, and to strengthen communications between research scientists and engineers involved in agricultural research. Approximately 71 individuals actively engaged in agricultural aviation research were invited to participate in the workshop. These were persons familiar with problems related to agricultural aviation and processing expertise which are of value for identifying and proposing beneficial research.

  8. Illness in the Returned International Traveler.

    PubMed

    Sanford, Christopher A; Fung, Claire

    2016-03-01

    Familiarity with the distribution, mode of transmission, and risk factors for acquisition of illnesses commonly transmitted to travelers to low-income nations can help guide clinicians in their work-up of an ill returned traveler. The 3 most common categories of illness in returned international travelers are gastrointestinal illness, fever, and dermatoses. Diarrhea is the most common illness reported in returned international travelers. Fever is a marker of a potentially significant illness; work-up of the ill febrile returned traveler should be conducted promptly. PMID:26900121

  9. Bulgarian Turkish emigration and return.

    PubMed

    Vasileva, D

    1992-01-01

    The main factors which determined the 1989 migration of Turks in Bulgaria back to Turkey are discussed. Background history is provided. After World War I, Turks in bulgaria comprised 10% of the total population. Bulgarian policy had been, up to the 1980s to send Rumelian Turks back, but the policy after 1980 was one of a national revival process to integrate Turks into the developed socialist society. Muslim traditions, customs, and Turkish language were interfered with. International disfavor resulted. In May 1989, the Communist Party declared, in an effort to show democratic ideals, open borders. Thus began the new emigration wave. 369,839 people fled to the Turkish border. 43% of the 9.47 ethnic Turks in bulgaria went to Turkey within 4 months. The numbers decreased in November, and soon after the communist regime ended. New laws were adopted allowing Turks to assume their original Turkish names. The huge migration was clearly political, and as such, the emigrant Turks should be determined as refugees and asylum seekers. The provocation of ethnic Turks was used by the communist regime to solve potential social conflicts. Not only did Turks flee to escape from violence or for religious, cultural, and moral reasons but also due to free market initiatives begun in Turkey in the early 1980s which improved Turkish quality of life. Food and consumer goods were cheaper and economic advantages were perceived. Emigrants were primarily peasants with lower levels of education, professional qualifications, and labor skills. 154,937 (42%) returned to bulgaria and 58% stayed in Turkey to comprise 25% of the former Turkish population. During this period, tensions between countries was high.l Bulgarians actively encouraged emigration and Turkey welcomed it. The emigrants to Turkey were seen as foreigners (muhacir or gocmen) but were received with good will and were readily accepted into menial positions. Emigrants were confronted with political, linguistic, and cultural

  10. Vocational Agriculture Education: Agricultural Livestock Skills.

    ERIC Educational Resources Information Center

    Pierce, Greg

    Ten units of instruction are provided in this curriculum guide on agricultural livestock skills. Unit topics are as follow: (1) restraining, (2) vaccination, (3) livestock castration, (4) dehorning, (5) docking, (6) growth stimulants, (7) identification, (8) shearing, (9) hoof trimming, and (10) birth assistance. Each instructional unit generally…

  11. Modules in Agricultural Education for Agricultural Resources.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational and Career Curriculum Development.

    Each of the 31 curriculum modules in this packet for agricultural resources instruction contains a brief description of the module content, a list of the major division or units, the overall objective, objectives by units, content outline and suggested teaching methods, student application activities, and evaluation procedures. A list of resource…

  12. VOCATIONAL AGRICULTURE RECORD BOOK FOR PRODUCTION AGRICULTURE.

    ERIC Educational Resources Information Center

    1966

    FORMS ARE PROVIDED FOR RECORDING FINANCIAL INFORMATION ABOUT SUPERVISED FARM PROGRAM ENTERPRISES BY INDIVIDUAL VOCATIONAL AGRICULTURE STUDENTS. THE BOOK IS DESIGNED ON AN ENTERPRISE BASIS AND PROVIDES SPACE FOR AGREEMENTS, INVENTORIES, EXPENSES, INCOME, SUMMARIES, AND ANALYSES. ASSISTANCE FOR TEACHERS USING THIS RECORD BOOK IS AVAILABLE IN "GUIDE…

  13. Modules in Agricultural Education for Agricultural Mechanics.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational and Career Curriculum Development.

    Each of the 38 curriculum modules in this packet for agricultural mechanics instruction contains a brief description of the module content, a list of the major divisions or units, the overall objectives, objectives by unit, content outline and suggested teaching methods, student application activities, and evaluation procedures. A listing of…

  14. Flow separation detector

    NASA Technical Reports Server (NTRS)

    Mateer, G. C.; Brosh, A. (Inventor)

    1977-01-01

    An arrangement for sensing the fluid separation along a surface which employs a thermally insulating element having a continuous surface blending into and forming a part of the fluid flow surface is described. A sudden decrease in the temperature of the downstream sensor conductor and concomitant increase in the temperature of the upstream sensor conductor is an indication of the separation. When the temperatures are returned to the state achieved during normal flow, the indicator thereby indicates the normal, attached fluid flow. The conductors may be, for example, wires or thin films, and should be within the viscous sub-layer of the expected fluid flow. A single heater and several pairs of sensors and corresponding sensor conductors may be used to detect not only the fluid flow and the separation, but the direction of the fluid flow, over the fluid flow surface.

  15. 12 CFR 210.12 - Return of cash items and handling of returned checks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Bank, and any other Reserve Bank or returning bank to which the returned check is sent, to handle the... paragraph (c)(3) of this section. (h) Reserve Bank's responsibility. A Reserve Bank shall handle a...

  16. AGRICULTURAL HEALTH STUDY

    EPA Science Inventory

    The Agricultural Health Study is a large cohort of 90,000 licensed pesticide applicators, plus 30,000 spouses and 20,000 children who are exposed either directly or indirectly. Exposure to pesticides is widespread and is important beyond the agricultural community. Other exposure...

  17. Personal Achievement Reading: Agriculture.

    ERIC Educational Resources Information Center

    Rozeboom, Deborah A.

    Exercises are provided in a set of five workbooks designed to aid students in agricultural programs in building vocabulary and reading skills. Each workbook borrows from terminology of agriculture to provide explanations and exercises for a sequential series of instructional objectives. One workbook concentrates on the ability to determine word…

  18. Agriculture and Rural Viability.

    ERIC Educational Resources Information Center

    North Carolina State Univ., Raleigh. Agricultural Experiment Station.

    Agriculture and the rural economic bases in mining, fisheries, forestry, and natural resource extraction are experiencing major social and economic changes. The farm and rural crises of the 1980s are not short-term aberrations, but symptoms of long-term trends that were partially hidden by the relatively good times for agriculture and rural areas…

  19. Theme: Urban Agriculture.

    ERIC Educational Resources Information Center

    Ellibee, Margaret; And Others

    1990-01-01

    On the theme of secondary agricultural education in urban areas, this issue includes articles on opportunities, future directions, and implications for the profession; creative supervised experiences for horticulture students; floral marketing, multicultural education; and cultural diversity in urban agricultural education. (JOW)

  20. Precision agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture is a new farming practice that has been developing since late 1980s. It has been variously referred to as precision farming, prescription farming, site-specific crop management, to name but a few. There are numerous definitions for precision agriculture, but the central concept...

  1. Agriculture in the Midwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in the Midwest United States (Illinois, Indiana, Iowa, Michigan, Minnesota, Ohio, and Wisconsin) represents one of the most intense areas of agriculture in the world. This area is not only critically important for the United States, but also for world exports of grain and meat for the Un...

  2. Agricultural Technology Opportunities.

    ERIC Educational Resources Information Center

    North Carolina State Board of Education, Raleigh. Agricultural Technology Education Section.

    Agricultural education programs available through North Carolina's newly created system of industrial education center, technical institutes, and community colleges are described. The information is for use by administrators, and teachers of adult agricultural courses and counselors of high school dropouts and graduates. It describes the need for…

  3. Vocational Agriculture I.

    ERIC Educational Resources Information Center

    Patton, Bob; Harp, Keith

    These course materials are designed to provide a foundation of basic knowledge in production agriculture as a prelude to further education in vocational agriculture. The guide contains 6 sections and 22 units of instruction. Each unit includes all or most of eight basic components: performance objectives, suggested activities for the teacher,…

  4. Ecological Models: Agricultural Models

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The agricultural research community is faced with a wide array of complex problems to solve. Continued population increases in developing countries require increased agricultural production, while agroecosystems are being stressed and negatively impacted by greater use of water and agrochemicals. F...

  5. Agriculture Power and Machinery.

    ERIC Educational Resources Information Center

    Rogers, Tom

    This guide is intended to assist vocational agriculture teachers who are teaching secondary- or postsecondary-level courses in agricultural power and machinery. The materials presented are based on the Arizona validated occupational competencies and tasks for the following occupations: service manager, shop foreman, service technician, and tractor…

  6. Global Transformations and Agriculture.

    ERIC Educational Resources Information Center

    Campbell, Rex R.

    1990-01-01

    Examines worldwide political, economic, and social transformations and their impact on agriculture, focusing on biotechnology. Discusses rise of international corporations and accompanying constraints on government power. Sees trend toward increasing agribusiness role in world food and agricultural sectors. Calls for broader views and research in…

  7. Managing agricultural drainage ditches for water quality protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are essential for the removal of surface and ground water to allow for crop production in poorly drained agricultural landscapes. Ditches also mediate the flow of pollutants from agroecosystems to downstream water bodies. This paper provides an overview of the science, ...

  8. Teaching Materials for Environmental Related Courses in Agriculture Occupations Programs.

    ERIC Educational Resources Information Center

    Bohning, Kermit B.; Stitt, Thomas R.

    The lesson plans were designed to provide the practicing applied biological and agricultural occupations teacher with a series of units setting down a basic foundation in Environmental Education. Nine lesson plans cover (1) ecosystems and agriculture, (2) biotic communities and food chains, (3) energy and nutrient flow, (4) land use and supply,…

  9. Direct flow crystal growth system

    DOEpatents

    Montgomery, Kenneth E.; Milanovich, Fred P.

    1992-01-01

    A crystal is grown in a constantly filtered solution which is flowed directly into the growing face of a crystal. In a continuous flow system, solution at its saturation temperature is removed from a crystal growth tank, heated above its saturation temperature, filtered, cooled back to its saturation temperature, and returned to the tank.

  10. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  11. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  12. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  13. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  14. 27 CFR 41.112 - Tax return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Tax return. 41.112 Section 41.112 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... States Deferred Payment of Tax in Puerto Rico on Tobacco Products § 41.112 Tax return. The...

  15. Returned Solar Max hardware degradation study results

    NASA Technical Reports Server (NTRS)

    Triolo, Jack J.; Ousley, Gilbert W.

    1989-01-01

    The Solar Maximum Repair Mission returned with the replaced hardware that had been in low Earth orbit for over four years. The materials of this returned hardware gave the aerospace community an opportunity to study the realtime effects of atomic oxygen, solar radiation, impact particles, charged particle radiation, and molecular contamination. The results of these studies are summarized.

  16. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Return premium. 308.514 Section 308.514 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will...

  17. Anxiety and the Newly Returned Adult Student

    ERIC Educational Resources Information Center

    Cleary, Michelle Navarre

    2012-01-01

    Based on interviews with students who had recently returned to school, this essay demonstrates the need for, challenges of, and ways to respond to the writing anxiety many adults bring with them back to school. Jessica and Sam were two of twenty-five newly returned adult students whom the author spent over sixty hours interviewing in the fall of…

  18. Aggregate Unemployment Decreases Individual Returns to Education

    ERIC Educational Resources Information Center

    Ammermueller, Andreas; Kuckulenz, Anja; Zwick, Thomas

    2009-01-01

    Aggregate unemployment may affect individual returns to education through qualification-specific responses in participation and wage bargaining. This paper shows that an increase in regional unemployment by 1% decreases returns to education by 0.005 percentage points. This implies that higher skilled employees are better sheltered from labour…

  19. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Return premium. 308.514 Section 308.514 Shipping... Cargo Insurance Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be... in the computation of a premium, or the insured goods were short-shipped. An application for...

  20. 46 CFR 308.514 - Return premium.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Return premium. 308.514 Section 308.514 Shipping... Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.514 Return premium. No premium will be... in the computation of a premium, or the insured goods were short-shipped. An application for...

  1. 26 CFR 50.7 - Returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) REGULATIONS RELATING TO THE TAX IMPOSED WITH RESPECT TO CERTAIN HYDRAULIC MINING § 50.7 Returns. (a) Form of... on which hydraulic mining operations began and ended during the taxable year for which the return is made; (7) The number of cubic yards mined by the hydraulic process at the mine during the taxable...

  2. 76 FR 14827 - Disclosure of Returns and Return Information to Designee of Taxpayer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... Internal Revenue Service 26 CFR Part 301 RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice of proposed... the period for submission to the IRS of taxpayer authorizations permitting disclosure of returns...

  3. Agricultural sustainability: concepts, principles and evidence.

    PubMed

    Pretty, Jules

    2008-02-12

    Concerns about sustainability in agricultural systems centre on the need to develop technologies and practices that do not have adverse effects on environmental goods and services, are accessible to and effective for farmers, and lead to improvements in food productivity. Despite great progress in agricultural productivity in the past half-century, with crop and livestock productivity strongly driven by increased use of fertilizers, irrigation water, agricultural machinery, pesticides and land, it would be over-optimistic to assume that these relationships will remain linear in the future. New approaches are needed that will integrate biological and ecological processes into food production, minimize the use of those non-renewable inputs that cause harm to the environment or to the health of farmers and consumers, make productive use of the knowledge and skills of farmers, so substituting human capital for costly external inputs, and make productive use of people's collective capacities to work together to solve common agricultural and natural resource problems, such as for pest, watershed, irrigation, forest and credit management. These principles help to build important capital assets for agricultural systems: natural; social; human; physical; and financial capital. Improving natural capital is a central aim, and dividends can come from making the best use of the genotypes of crops and animals and the ecological conditions under which they are grown or raised. Agricultural sustainability suggests a focus on both genotype improvements through the full range of modern biological approaches and improved understanding of the benefits of ecological and agronomic management, manipulation and redesign. The ecological management of agroecosystems that addresses energy flows, nutrient cycling, population-regulating mechanisms and system resilience can lead to the redesign of agriculture at a landscape scale. Sustainable agriculture outcomes can be positive for food

  4. Maximizing your return on people.

    PubMed

    Bassi, Laurie; McMurrer, Daniel

    2007-03-01

    Though most traditional HR performance metrics don't predict organizational performance, alternatives simply have not existed--until now. During the past ten years, researchers Laurie Bassi and Daniel McMurrer have worked to develop a system that allows executives to assess human capital management (HCM) and to use those metrics both to predict organizational performance and to guide organizations' investments in people. The new framework is based on a core set of HCM drivers that fall into five major categories: leadership practices, employee engagement, knowledge accessibility, workforce optimization, and organizational learning capacity. By employing rigorously designed surveys to score a company on the range of HCM practices across the five categories, it's possible to benchmark organizational HCM capabilities, identify HCM strengths and weaknesses, and link improvements or back-sliding in specific HCM practices with improvements or shortcomings in organizational performance. The process requires determining a "maturity" score for each practice, based on a scale of 1 (low) to 5 (high). Over time, evolving maturity scores from multiple surveys can reveal progress in each of the HCM practices and help a company decide where to focus improvement efforts that will have a direct impact on performance. The authors draw from their work with American Standard, South Carolina's Beaufort County School District, and a bevy of financial firms to show how improving HCM scores led to increased sales, safety, academic test scores, and stock returns. Bassi and McMurrer urge HR departments to move beyond the usual metrics and begin using HCM measurement tools to gauge how well people are managed and developed throughout the organization. In this new role, according to the authors, HR can take on strategic responsibility and ensure that superior human capital management becomes central to the organization's culture. PMID:17348175

  5. Issues of sustainable irrigated agriculture in the San Joaquin Valley of California in a changing regulatory environment concerning water quality and protection of wildlife

    SciTech Connect

    Quinn, N.W.T.; Delamore, M.L.

    1994-06-01

    Since the discovery of selenium toxicosis in the Kesterson Reservoir in the San Joaquin Valley, California, public perception of irrigated agriculture as a benign competitor for California`s developed water supply has been changed irrevocably. Subsurface return flows from irrigated agriculture were implicated as the source of selenium which led to incidents of reproductive failure in waterfowl and threatened survival of other fish and wildlife species. Stringent water quality objectives were promulgated to protect rivers, tributaries, sloughs and other water bodies receiving agricultural discharges from selenium contamination. Achieving these objectives was left to the agricultural water districts, federal and state agencies responsible for drainage and water quality enforcement in the San Joaquin Basin. This paper describes some of the strategies to improve management of water resources and water quality in response to these new environmental objectives. Similar environmental objectives will likely be adopted by other developed and developing countries with large regions of arid zone agriculture and susceptible wildlife resources. A series of simulation models have been developed over the past four years to evaluate regional drainage management strategies such as: irrigation source control; drainage recycling; selective retirement of agricultural land; regional shallow ground water pumping; coordination of agricultural drainage, wetland and reservoir releases; and short-term ponding of drainage water. A new generation of Geographic Information Service-based software is under development to bridge the gap between planning and program implementation. Use of the decision support system will allow water districts and regulators to continuously monitor drainage discharges to the San Joaquin River in real-time and to assess impacts of management strategies that have been implemented to take advantage of the River`s assimilative capacity for trace elements and salts.

  6. Feeding and healing the world: through regenerative agriculture and permaculture.

    PubMed

    Rhodes, Christopher J

    2012-01-01

    The study of soil is a mature science, whereas related practical methods of regenerative agriculture and permaculture are not. However, despite a paucity of detailed peer reviewed research published on these topics, there is overwhelming evidence both that the methods work and they may offer the means to address a number of prevailing environmental challenges, e.g. peak oil, climate change, carbon capture, unsustainable agriculture and food shortages, peak phosphorus (phosphate), water shortages, environmental pollution, desert reclamation, and soil degradation. What is lacking is a proper scientific study, made in hand with actual development projects. By elucidating the scientific basis of these remarkable phenomena, we may obtain the means for solving some of the otherwise insurmountable problems confronting humanity, simply by observing, and working with, the patterns and forces of nature. This article is intended as a call to arms to make serious investment in researching and actualising these methods on a global scale. Despite claims that peak oil is no longer a threat because vast resources of gas and shale oil (tight oil) can now be recovered by fracking (hydraulic fracturing) combined with horizontal drilling, the reality is that proven actual reserves are only adequate to delay the peak by a few years. Furthermore, because of the rapid depletion rates of flow from gas wells and oil wells that are accessed by fracking, it will be necessary to drill continuously and relentlessly to maintain output, and there are material limits of equipment, technology and trained personnel to do this. Moreover, to make any sensible difference to the liquid fuel crisis, which is the most immediate consequence of peak oil, it would be necessary to convert the worlds one billion vehicles to run on natural gas rather than liquid fuels refined from crude oil, and this would take some considerable time and effort. The loss of widespread personalised transportation is thus

  7. An Analysis of Profitability Factors for Selected Farming Types in the Minnesota Vocational Agriculture Farm Management Education Program.

    ERIC Educational Resources Information Center

    Kleene, Marvin

    1980-01-01

    A study was conducted to determine the impact profitability factors have on farm labor earnings for farms enrolled in the Minnesota Vocational Agriculture Farm Management Education Program. The most important predictors of labor earnings were size of business, gross return per cropped acre, and index return per $100 of feed fed. (LRA)

  8. Agricultural lung disease.

    PubMed

    Spurzem, John R; Romberger, Debra J; Von Essen, Susanna G

    2002-12-01

    Agricultural work is associated with high rates of injury, disability, and illness. Agricultural workers are at increased risk for a variety of illnesses including respiratory disorders, dermatologic conditions, and cancer. The recognition of ODTS led to increased understanding of acute illness in farmers and grain workers. Previously, many cases of acute illness were probably erroneously called farmer's lung. The same agents that are responsible for ODTS are responsible for the high prevalence of bronchitis in certain agricultural workers. The recent description of the innate immune system is very exciting because it will lead to increased understanding of the pathogenesis of organic dust induced disorders. PMID:12512166

  9. A coupled stochastic inverse-management framework for dealing with nonpoint agriculture pollution under groundwater parameter uncertainty

    NASA Astrophysics Data System (ADS)

    Llopis-Albert, Carlos; Palacios-Marqués, Daniel; Merigó, José M.

    2014-04-01

    In this paper a methodology for the stochastic management of groundwater quality problems is presented, which can be used to provide agricultural advisory services. A stochastic algorithm to solve the coupled flow and mass transport inverse problem is combined with a stochastic management approach to develop methods for integrating uncertainty; thus obtaining more reliable policies on groundwater nitrate pollution control from agriculture. The stochastic inverse model allows identifying non-Gaussian parameters and reducing uncertainty in heterogeneous aquifers by constraining stochastic simulations to data. The management model determines the spatial and temporal distribution of fertilizer application rates that maximizes net benefits in agriculture constrained by quality requirements in groundwater at various control sites. The quality constraints can be taken, for instance, by those given by water laws such as the EU Water Framework Directive (WFD). Furthermore, the methodology allows providing the trade-off between higher economic returns and reliability in meeting the environmental standards. Therefore, this new technology can help stakeholders in the decision-making process under an uncertainty environment. The methodology has been successfully applied to a 2D synthetic aquifer, where an uncertainty assessment has been carried out by means of Monte Carlo simulation techniques.

  10. Reliability, return periods, and risk under nonstationarity

    NASA Astrophysics Data System (ADS)

    Read, Laura K.; Vogel, Richard M.

    2015-08-01

    Water resources design has widely used the average return period as a concept to inform management and communication of the risk of experiencing an exceedance event within a planning horizon. Even though nonstationarity is often apparent, in practice hydrologic design often mistakenly assumes that the probability of exceedance, p, is constant from year to year which leads to an average return period To equal to 1/p; this expression is far more complex under nonstationarity. Even for stationary processes, the common application of an average return period is problematic: it does not account for planning horizon, is an average value that may not be representative of the time to the next flood, and is generally not applied in other areas of water planning. We combine existing theoretical and empirical results from the literature to provide the first general, comprehensive description of the probabilistic behavior of the return period and reliability under nonstationarity. We show that under nonstationarity, the underlying distribution of the return period exhibits a more complex shape than the exponential distribution under stationary conditions. Using a nonstationary lognormal model, we document the increased complexity and challenges associated with planning for future flood events over a planning horizon. We compare application of the average return period with the more common concept of reliability and recommend replacing the average return period with reliability as a more practical way to communicate event likelihood in both stationary and nonstationary contexts.

  11. Comet nucleus and asteroid sample return missions

    NASA Astrophysics Data System (ADS)

    Melton, Robert G.; Thompson, Roger C.; Starchville, Thomas F., Jr.; Adams, C.; Aldo, A.; Dobson, K.; Flotta, C.; Gagliardino, J.; Lear, M.; McMillan, C.

    During the 1991-92 academic year, the Pennsylvania State University has developed three sample return missions: one to the nucleus of comet Wild 2, one to the asteroid Eros, and one to three asteroids located in the Main Belt. The primary objective of the comet nucleus sample return mission is to rendezvous with a short period comet and acquire a 10 kg sample for return to Earth. Upon rendezvous with the comet, a tethered coring and sampler drill will contact the surface and extract a two-meter core sample from the target site. Before the spacecraft returns to Earth, a monitoring penetrator containing scientific instruments will be deployed for gathering long-term data about the comet. A single asteroid sample return mission to the asteroid 433 Eros (chosen for proximity and launch opportunities) will extract a sample from the asteroid surface for return to Earth. To limit overall mission cost, most of the mission design uses current technologies, except the sampler drill design. The multiple asteroid sample return mission could best be characterized through its use of future technology including an optical communications system, a nuclear power reactor, and a low-thrust propulsion system. A low-thrust trajectory optimization code (QuickTop 2) obtained from the NASA LeRC helped in planning the size of major subsystem components, as well as the trajectory between targets.

  12. Comet nucleus and asteroid sample return missions

    NASA Technical Reports Server (NTRS)

    Melton, Robert G.; Thompson, Roger C.; Starchville, Thomas F., Jr.; Adams, C.; Aldo, A.; Dobson, K.; Flotta, C.; Gagliardino, J.; Lear, M.; Mcmillan, C.

    1992-01-01

    During the 1991-92 academic year, the Pennsylvania State University has developed three sample return missions: one to the nucleus of comet Wild 2, one to the asteroid Eros, and one to three asteroids located in the Main Belt. The primary objective of the comet nucleus sample return mission is to rendezvous with a short period comet and acquire a 10 kg sample for return to Earth. Upon rendezvous with the comet, a tethered coring and sampler drill will contact the surface and extract a two-meter core sample from the target site. Before the spacecraft returns to Earth, a monitoring penetrator containing scientific instruments will be deployed for gathering long-term data about the comet. A single asteroid sample return mission to the asteroid 433 Eros (chosen for proximity and launch opportunities) will extract a sample from the asteroid surface for return to Earth. To limit overall mission cost, most of the mission design uses current technologies, except the sampler drill design. The multiple asteroid sample return mission could best be characterized through its use of future technology including an optical communications system, a nuclear power reactor, and a low-thrust propulsion system. A low-thrust trajectory optimization code (QuickTop 2) obtained from the NASA LeRC helped in planning the size of major subsystem components, as well as the trajectory between targets.

  13. Mars sample return: The critical next step

    NASA Astrophysics Data System (ADS)

    Clark, Benton C.

    2007-06-01

    Before humans trek the mountains and canyons of Mars, a key event must happen. That vital undertaking will be to fly a roundtrip mission to Mars for acquiring representative surface materials and returning them to Earth. Mars sample return has also been a premier objective of planetary scientists for more than four decades. In the meantime, the Stardust mission has returned dust grains from a comet, and Genesis has collected and returned solar wind. Yet at this time, Mars sample return is no longer an official project in any space agency. Inestimable value would also accrue for engineering the systems needed for future human missions. Sample return from the surface will validate our collective ability to successfully accomplish such a roundtrip to Mars in absence of the ability for end-to-end testing on Earth. Embarking on a historic Mars surface sample return mission will provide the confirming signal that a space program is ready, willing, and capable to achieve the next major engineering challenge for exploration of our solar system. Beginning serious development of the missing critical link, the Mars Ascent Vehicle, will signal the beginning of this undertaking.

  14. Integrating public perspectives in sample return planning.

    PubMed

    Race, M S; MacGregor, D G

    2000-01-01

    Planning for extraterrestrial sample returns--whether from Mars or other solar system bodies--must be done in a way that integrates planetary protection concerns with the usual mission technical and scientific considerations. Understanding and addressing legitimate societal concerns about the possible risks of sample return will be a critical part of the public decision making process ahead. This paper presents the results of two studies, one with lay audiences, the other with expert microbiologists designed to gather information on attitudes and concerns about sample return risks and planetary protection. Focus group interviews with lay subjects, using generic information about Mars sample return and a preliminary environmental impact assessment, were designed to obtain an indication of how the factual content is perceived and understood by the public. A research survey of microbiologists gathered information on experts' views and attitudes about sample return, risk management approaches and space exploration risks. These findings, combined with earlier research results on risk perception, will be useful in identifying levels of concern and potential conflicts in understanding between experts and the public about sample return risks. The information will be helpful in guiding development of the environmental impact statement and also has applicability to proposals for sample return from other solar system bodies where scientific uncertainty about extraterrestrial life may persist at the time of mission planning. PMID:12038482

  15. Integrating Public Perspectives in Sample Return Planning

    NASA Technical Reports Server (NTRS)

    Race, Margaret S.; MacGregor, G.

    2001-01-01

    Planning for extraterrestrial sample returns, whether from Mars or other solar system bodies, must be done in a way that integrates planetary protection concerns with the usual mission technical and scientific considerations. Understanding and addressing legitimate societal concerns about the possible risks of sample return will be a critical part of the public decision making process ahead. This paper presents the results of two studies, one with lay audiences, the other with expert microbiologists, designed to gather information, on attitudes and concerns about sample return risks and planetary protection. Focus group interviews with lay subjects, using generic information about Mars sample return and a preliminary environmental impact assessment, were designed to obtain an indication of how the factual content is perceived and understood by the public. A research survey of microbiologists gathered information on experts' views and attitudes about sample return, risk management approaches and space exploration risks. These findings, combined with earlier research results on risk perception, will be useful in identifying levels of concern and potential conflicts in understanding between experts and the public about sample return risks. The information will be helpful in guiding development of the environmental impact statement and also has applicability to proposals for sample return from other solar system bodies where scientific uncertainty about extraterrestrial life may persist at the time of mission planning.

  16. An Urban Agricultural Program

    ERIC Educational Resources Information Center

    Foster, Parker V.

    1974-01-01

    A program of Agricultural Education (primarily horticulture) was started in the San Diego, California school district in 1967. The philosophy behind the program, the growth in terms of students involved, and the structural framework of the program are outlined. (KP)

  17. Serving Agriculture's "Big Business"

    ERIC Educational Resources Information Center

    Schake, L. M.

    1970-01-01

    A new dimension and challenge in Extension activities is emerging as some phases of agriculture evolve from small operations to multimillion dollar agribusiness ventures; the beef cattle commercial feedlot industry in the Southwest is a good example. (EB)

  18. Agricultural chemistry and bioenergy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Renewed interest in converting biomass to biofuels such as ethanol, other forms of bioenergy, and bioenergy byproducts or coproducts of commercial value opens opportunities for chemists, including agricultural chemists and related disciplines. Applications include feedstock characterization and quan...

  19. Department of Agriculture

    MedlinePlus

    ... and Science Rural and Community Development Rural Opportunities Trade Travel and Recreation USDA for Kids Programs and ... and Agriculture Research OPEDA Scholarship Program MARKETING AND TRADE Exporting Goods Importing Goods Newsroom Agency News Releases ...

  20. Agricultural Research Service

    MedlinePlus

    ... Quality Review Office of Technology Transfer National Program Research Areas Animal Production and Protection Crop Production and Protection Natural Resources and Sustainable Agricultural Systems Nutrition, Food Safety, and Quality Overseas ...

  1. The Agriculture Grants Program.

    ERIC Educational Resources Information Center

    Krogmann, David W.; Key, Joe

    1981-01-01

    Reviews historical background surrounding the origins of the Competitive Research Grants Office, established in 1978 to support basic research related to agriculture. Describes current controversy within the legislature which threatens its existence. (CS)

  2. GREENHOUSE GASES AND AGRICULTURE

    EPA Science Inventory

    Agriculture ranks third in its contribution to Earth's anthropogenically nhanced greenhouse effect. Energy use and production and chlorofluorocarbons are anked first and second, respectively.) pecifically, greenhouse gas sources and inks are increased, and sinks are decreased, by...

  3. Toward a Sustainable Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Future trends in population growth, energy use, climate change, and globalization will challenge agriculturists to develop innovative production systems that are highly productive and environmentally sound. Furthermore, future agricultural production systems must possess an inherent capacity to adap...

  4. Technology for return of planetary samples

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Technological requirements of a planetary return sample mission were studied. The state-of-the-art for problems unique to this class of missions was assessed and technological gaps were identified. The problem areas where significant advancement of the state-of-the-art is required are: life support for the exobiota during the return trip and within the Planetary Receiving Laboratory (PRL); biohazard assessment and control technology; and quarantine qualified handling and experimentation methods and equipment for studying the returned sample in the PRL. Concepts for solving these problems are discussed.

  5. Return to Play Following Hip Arthroscopy.

    PubMed

    Lee, Simon; Kuhn, Andrew; Draovitch, Pete; Bedi, Asheesh

    2016-10-01

    Femoroacetabular impingement may be particularly disabling to the high-demand athlete, especially those with significant cutting and pivoting requirements. If nonoperative treatment fails to adequately alleviate symptoms or sufficiently restore function in the athlete, hip arthroscopy can lead to improved pain, improved range of motion, and high rates of return to play with proper postoperative rehabilitation. The rate of return to previous level of competition is also high with accurate diagnosis and well-executed correction of deformity. A clear understanding of the etiology, diagnosis, management, and outcomes is essential for clinicians to optimally help patients to return to play. PMID:27543404

  6. GEOS-1 laser pulse return shape analysis

    NASA Technical Reports Server (NTRS)

    Felsentreger, T. L.

    1972-01-01

    An attempt has been made to predict the shape of the laser return pulse from the corner cube retroreflectors on the GEOS-1 spacecraft. The study is geometrical only, and neglects factors such as optical interference, atmospheric perturbations, etc. A function giving the intensity of the return signal at any given time has been derived. In addition, figures are given which show the predicted return pulse shape as a function of time, the angle between the beam and the spin axis, and an in-plane angle (designating the orientation of the intersection of the planar waves with the plane of the corner cubes).

  7. Irrigated Agriculture, Saudi Arabia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    In Saudi Arabia, center-pivot, swing-arm irrigated agriculture complexes such as the one imaged at Jabal Tuwayq (20.5N, 45.0 E) extract deep fossil water reserves to achieve food crop production self sufficiency in this desert environment. The significance of the Saudi expanded irrigated agriculture is that the depletion of this finite water resource is a short term solution to a long term need that will still exist when the water has been extracted.

  8. Lunar agriculture in Mesoamerica

    NASA Astrophysics Data System (ADS)

    Iwaniszewski, S.

    Through the moon' s role in choosing the proper time for planting, harvesting and woodcutting is widely attested in ethnographic reports, the cultural logic and structure of actions by which this celestial body is perceived and used has not been satisfactorily explained. The aim of this paper is to offer such an explanatory framework within which the role of the moon in the agricultural cycle may be explained. My examples of the beliefs about lunar agriculture derive from the Mesoamerican cultural tradition.

  9. Agriculture increases individual fitness.

    PubMed

    Kovaka, Karen; Santana, Carlos; Patel, Raj; Akçay, Erol; Weisberg, Michael

    2016-01-01

    We question the need to explain the onset of agriculture by appealing to the second type of multilevel selection (MLS2). Unlike eusocial insect colonies, human societies do not exhibit key features of evolutionary individuals. If we avoid the mistake of equating Darwinian fitness with health and quality of life, the adoption of agriculture is almost certainly explicable in terms of individual-level selection and individual rationality. PMID:27561384

  10. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...—(i) Form CT-1. An employer required to make returns on Form CT-1 who in any return period ceases to pay taxable compensation shall make the return on Form CT-1 for such period as a final return. Such... ceased to pay taxable compensation shall continue to file returns on Form CT-1. (ii) Form CT-2....

  11. Evaluating alternative agricultural management practices for a minor agricultural watershed using the ADAPT method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, a spatial-process based water quality model was calibrated (2001-2002) for flow, sediment, nitrate and phosphorus losses from the High Island Creek, a 3856 ha agricultural watershed located in south-central Minnesota. The calibrated model was used to evaluate alternative tillage and ...

  12. Agricultural land management options following large-scale environmental contamination.

    PubMed

    Vandenhove, Hildegarde; Turcanu, Catrinel

    2011-07-01

    The recent events at the Fukushima Daiichi nuclear power plant, in Japan, have raised questions about the accumulation of radionuclides in soils, the transfer in the food chain, and the possibility for restricted land use in the foreseeable future. This article summarizes what is generally understood about the application of agricultural countermeasures as a land management option to reduce the transfer of radionuclides in the food chain and to facilitate the return of potentially affected soils to agricultural practices in the vicinity of the Fukushima plant. PMID:21608113

  13. Fluctuation behaviors of financial return volatility duration

    NASA Astrophysics Data System (ADS)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  14. Returning to sports after a back injury

    MedlinePlus

    ... to return to the sport with your doctor, physical therapist, or other health care providers? Have you been ... sport, talk to your health care provider and physical therapist about whether you can do this safely. Contact ...

  15. Analysis and representation of sonar echo returns

    NASA Astrophysics Data System (ADS)

    Hackman, Roger H.; Abatzoglou, Theagenis J.; Arnold, Hal B.; Reagan, John T.

    1993-10-01

    Active acoustic classification of underwater targets is an important problem of current interest. The echo return of such objects has components related to such distinct dynamical elements as the specular (geometric) return, reradiation of elastic resonances, diffracted (or Franz) waves, etc. The arrival times and spectral content of these components will generally give information about the structure and geometry of the scatterer. This information is reflected to the time- frequency structure of the echo return. In this paper, a comparative study is presented of the time-frequency analysis capability of a number of tools in applications to the echo structure of finite elastic cylinders. The time-frequency tools considered include the Wigner-Ville distribution, the Choi-Williams distribution, the Gabor transform, and the continuous wavelet transforms. The comparison is based on echo returns that have been synthesized from numerical T-matrix solutions to the associated free-field scattering problems.

  16. Spectral characteristics of the MST radar returns

    NASA Technical Reports Server (NTRS)

    Rastogi, P. K.

    1983-01-01

    The salient features of the spectra of atmospheric returns due to random refractivity fluctuations in the Mesosphere, Stratosphere, Troposphere MST region are reviewed. The nonhomogeneous layered structure of turbulence is often evident as multiple peaks in the spectra. The time evolution of the spectra observed with a fine Doppler resolution provides evidence for thin regions of turbulence associated with gravity waves and shear instabilities. Embedded in these regions are horizontally extended refractivity structures that produce enhanced returns due to specular reflections. It is conceivable that some enhanced returns arise due to anisotropy of small scale refractivity structures. Observed correlations of the strength of the returns with their Doppler spread, wind shears, and winds provide insights into the physical mechanisms that produce turbulence.

  17. Oxygen production for interplanetary return missions

    NASA Technical Reports Server (NTRS)

    Richter, R.; Ash, R.; Dowler, W.

    1980-01-01

    Interplanetary missions with extraterrestrial returns are limited by large propulsion mass requirements. The injected mass landed on an extraterrestrial body can be reduced substantially by utilizing indigenous materials for the production of propellant on the extraterrestrial body. Analyses reported show that for Mars return missions, in situ production of oxygen during the wait between landing and the next low-energy return opportunity reduces the Earth-launch mass requirements to the allowable limit for direct entry and direct return missions. A small chemical processor using radioisotope thermal energy can extract oxygen several times its own mass from carbon dioxide, during the several-hundred-days wait on Mars. The fundamental element of the concept is the electrolytic process. Solid electrolyte cells for extracting oxygen from gaseous feedstock are identified. The basic physical principles underlying the extraction process are analyzed, and the relations between the major parameters established. The laboratory equipment for experimental investigation of the process is presented.

  18. Insulate Steam Distribution and Condensate Return Lines

    SciTech Connect

    Not Available

    2006-01-01

    This revised ITP tip sheet on insulating steam distribution and condensate return lines provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  19. STS-26: The return to flight

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The major activities leading up to the return to flight of the Space Shuttles are summarized. Major orbiter modifications and solid rocket motor redesign are described. Shuttle payloads are discussed briefly. Also provided are the biographies of the crew.

  20. Mercury Sample Return using Solar Sails

    NASA Technical Reports Server (NTRS)

    Montgomery, Edward E.; Young, Roy M.; Adams, Charles L.

    2006-01-01

    A conventional Mercury sample return mission requires significant launch mass due to the large deltav required for the outbound and return trips, and the large mass of a planetary lander and ascent vehicle. Solar sailing can be used to reduce lander mass allocation by delivering the lander to a low, thermally safe orbit close to the terminator. Propellant mass is not an issue for solar sails so a sample can be returned relatively easily, without resorting to lengthy, multiple gravity assists. The initial Mercury sample return studies reported here were conducted under ESA contract ESTEC/16534/02/NL/NR, PI Colin McInnes, Technical Officer Peter Falkner. Updated solar sail capabilities were developed under the Ground System Demonstration program, funded by the NASA's In-Space Propulsion Technology (ISPT) Program.

  1. Catchment scale analysis on river-return ratio of irrigation water from densely developed paddy areas

    NASA Astrophysics Data System (ADS)

    Yoshida, T.; Masumoto, T.; Horikawa, N.; Kudo, R.; Minakawa, H.; Nawa, N.

    2013-12-01

    Irrigation in Japan is predominantly used for rice cultivation, and it accounts for 70% of total water withdrawal. Water loss, which is attributable to nature of open channel irrigation system and percolation from fields, leads to relatively low irrigation efficiencies compared with ones for upland crops. However, because part of water gradually returns to rivers (river-return flow), it contributes to stable water use in downstream. This study investigated how irrigation water circulates and returns to rivers, and quantified a ratio of river-return flow to irrigation intake for an irrigation area (river-return ratio). One difficulty in river-return flow analysis lies in the fact that two types of flow pathways exist in an irrigation area; natural rivers that drain water from the areas, and channel networks whose directions do not necessarily coincide with river directions. In addition, outflux from irrigation area is consisted of water from different sources, such as water loss during water allocation, rainfall, irrigation, and influx from adjacent upstream areas. To cope with such difficulties, we used a grid-based distributed water circulation model that represents both catchment scale hydrological cycles and water flows related to irrigation channel network. The model calculates water flow for irrigation networks based on a GIS database of water use facilities. The model also incorporates operation rules for facilities and field level water management. Using the modeled river network, we first identify grid-cells where influx and outflux occurs across boundaries of irrigation areas. Then, to eliminate the effect of influx from adjacent upstream areas, we subtract influx from outflux. This makes us to capture outflux that purely originates in rainfall and irrigation within an irrigated area. Next, we separate the amount of outflux that originates in irrigation from the total amount of outflux. As residence time of each flow pathway had not been clarified yet, we

  2. Characterizing water flows in irrigated valleys of northern New Mexico

    NASA Astrophysics Data System (ADS)

    Ochoa, C. G.; Fernald, A.; Guldan, S.; Tidwell, V. C.

    2009-12-01

    Ditch seepage and deep percolation from irrigation in agricultural valleys of semi-arid regions can have multiple hydrological benefits including aquifer recharge, temporary storage, and delayed return flow. This study aims to advance scientific understanding of surface water and groundwater interactions in semi-arid region valleys of the western USA. The study is being conducted in three different irrigated valleys of the Rio Grande basin in northern New Mexico. The first site is a floodplain valley along the main stem of the Rio Grande; the second site is an upper valley along the Rio Hondo, a tributary to the Rio Grande; and the third site is a floodplain valley along the Rio Chama, which also is a tributary to the Rio Grande. Beginning in 2002, we instrumented the first study site to measure climate variables, surface water flows, and groundwater fluctuations due to deep percolation from irrigation and ditch seepage. Currently, we are installing field equipment at the second study site, and we will start instrumentation at the third study site in the spring of 2010. A multi-modeling approach is being used to extrapolate field-based results to larger spatial scales. One and two dimensional models like the Root Zone Water Quality Model and Hydrus, respectively, are being used to simulate physical processes in the vadose zone at the field scale, and the model GSFlow will be used to integrate surface water and groundwater components at the valley scale. Results from an ongoing study aimed to quantify water budget components at the first study site showed that up to 92% of the water diverted for irrigation in this floodplain valley returns back to the river, either as surface return flow (59%) or as shallow groundwater return flow that originated as canal seepage (12%) and deep percolation from irrigation (21%). Also, simulations with a System Dynamics Model showed that the coupled surface water irrigation system and shallow aquifer act together to store water

  3. Notes on Earth Atmospheric Entry for Mars Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Rivell, Thomas

    2006-01-01

    The entry of sample return vehicles (SRVs) into the Earth's atmosphere is the subject of this document. The Earth entry environment for vehicles, or capsules, returning from the planet Mars is discussed along with the subjects of dynamics, aerodynamics, and heat transfer. The material presented is intended for engineers and scientists who do not have strong backgrounds in aerodynamics, aerothermodynamics and flight mechanics. The document is not intended to be comprehensive and some important topics are omitted. The topics considered in this document include basic principles of physics (fluid mechanics, dynamics and heat transfer), chemistry and engineering mechanics. These subjects include: a) fluid mechanics (aerodynamics, aerothermodynamics, compressible fluids, shock waves, boundary layers, and flow regimes from subsonic to hypervelocity; b) the Earth s atmosphere and gravity; c) thermal protection system design considerations; d) heat and mass transfer (convection, radiation, and ablation); e) flight mechanics (basic rigid body dynamics and stability); and f) flight- and ground-test requirements; and g) trajectory and flow simulation methods.

  4. Hayabusa: Navigation Challenges for Earth Return

    NASA Technical Reports Server (NTRS)

    Haw, Robert J.; Bhaskaran, S.; Strauss, W.; Sklyanskiy, E.; Graat, E. J.; Smith, J. J.; Menom, P.; Ardalan, S.; Ballard, C.; Williams, P.; Kawaguchi, J.; Makoto, Y.; Ohnishi, T.

    2011-01-01

    Hayabusa was a JAXA sample-return mission to Itokawa navigated, in part, by JPL personnel. Hayabusa survived several near mission-ending failures at Itokawa yet returned to Earth with an asteroid regolith sample on June 13, 2010. This paper describes NASA/JPL's participation in the Hayabusa mission during the last 100 days of its mission, wherein JPL provided tracking data and orbit determination, plus verification of maneuver design and entry, descent and landing.

  5. 26 CFR 1.6033-4 - Required use of magnetic media for returns by organizations required to file returns under...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Required use of magnetic media for returns by...) Information Returns § 1.6033-4 Required use of magnetic media for returns by organizations required to file returns under section 6033. The return of an organization that is required to be filed on magnetic...

  6. Biosurfactants in agriculture.

    PubMed

    Sachdev, Dhara P; Cameotra, Swaranjit S

    2013-02-01

    Agricultural productivity to meet growing demands of human population is a matter of great concern for all countries. Use of green compounds to achieve the sustainable agriculture is the present necessity. This review highlights the enormous use of harsh surfactants in agricultural soil and agrochemical industries. Biosurfactants which are reported to be produced by bacteria, yeasts, and fungi can serve as green surfactants. Biosurfactants are considered to be less toxic and eco-friendly and thus several types of biosurfactants have the potential to be commercially produced for extensive applications in pharmaceutical, cosmetics, and food industries. The biosurfactants synthesized by environmental isolates also has promising role in the agricultural industry. Many rhizosphere and plant associated microbes produce biosurfactant; these biomolecules play vital role in motility, signaling, and biofilm formation, indicating that biosurfactant governs plant-microbe interaction. In agriculture, biosurfactants can be used for plant pathogen elimination and for increasing the bioavailability of nutrient for beneficial plant associated microbes. Biosurfactants can widely be applied for improving the agricultural soil quality by soil remediation. These biomolecules can replace the harsh surfactant presently being used in million dollar pesticide industries. Thus, exploring biosurfactants from environmental isolates for investigating their potential role in plant growth promotion and other related agricultural applications warrants details research. Conventional methods are followed for screening the microbial population for production of biosurfactant. However, molecular methods are fewer in reaching biosurfactants from diverse microbial population and there is need to explore novel biosurfactant from uncultured microbes in soil biosphere by using advanced methodologies like functional metagenomics. PMID:23280539

  7. Invariant Measures for Cherry Flows

    NASA Astrophysics Data System (ADS)

    Saghin, Radu; Vargas, Edson

    2013-01-01

    We investigate the invariant probability measures for Cherry flows, i.e. flows on the two-torus which have a saddle, a source, and no other fixed points, closed orbits or homoclinic orbits. In the case when the saddle is dissipative or conservative we show that the only invariant probability measures are the Dirac measures at the two fixed points, and the Dirac measure at the saddle is the physical measure. In the other case we prove that there exists also an invariant probability measure supported on the quasi-minimal set, we discuss some situations when this other invariant measure is the physical measure, and conjecture that this is always the case. The main techniques used are the study of the integrability of the return time with respect to the invariant measure of the return map to a closed transversal to the flow, and the study of the close returns near the saddle.

  8. Comet nucleus and asteroid sample return missions

    NASA Astrophysics Data System (ADS)

    1992-06-01

    Three Advanced Design Projects have been completed this academic year at Penn State. At the beginning of the fall semester the students were organized into eight groups and given their choice of either a comet nucleus or an asteroid sample return mission. Once a mission had been chosen, the students developed conceptual designs. These were evaluated at the end of the fall semester and combined into three separate mission plans, including a comet nucleus same return (CNSR), a single asteroid sample return (SASR), and a multiple asteroid sample return (MASR). To facilitate the work required for each mission, the class was reorganized in the spring semester by combining groups to form three mission teams. An integration team consisting of two members from each group was formed for each mission so that communication and information exchange would be easier among the groups. The types of projects designed by the students evolved from numerous discussions with Penn State faculty and mission planners at the Johnson Space Center Human/Robotic Spacecraft Office. Robotic sample return missions are widely considered valuable precursors to manned missions in that they can provide details about a site's environment and scientific value. For example, a sample return from an asteroid might reveal valuable resources that, once mined, could be utilized for propulsion. These missions are also more adaptable when considering the risk to humans visiting unknown and potentially dangerous locations, such as a comet nucleus.

  9. Mars Earth Return Vehicle (MERV) Propulsion Options

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; McGuire, Melissa L.; Burke, Laura; Fincannon, James; Warner, Joe; Williams, Glenn; Parkey, Thomas; Colozza, Tony; Fittje, Jim; Martini, Mike; Packard, Tom; Hemminger, Joseph; Gyekenyesi, John

    2010-01-01

    The COMPASS Team was tasked with the design of a Mars Sample Return Vehicle. The current Mars sample return mission is a joint National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) mission, with ESA contributing the launch vehicle for the Mars Sample Return Vehicle. The COMPASS Team ran a series of design trades for this Mars sample return vehicle. Four design options were investigated: Chemical Return /solar electric propulsion (SEP) stage outbound, all-SEP, all chemical and chemical with aerobraking. The all-SEP and Chemical with aerobraking were deemed the best choices for comparison. SEP can eliminate both the Earth flyby and the aerobraking maneuver (both considered high risk by the Mars Sample Return Project) required by the chemical propulsion option but also require long low thrust spiral times. However this is offset somewhat by the chemical/aerobrake missions use of an Earth flyby and aerobraking which also take many months. Cost and risk analyses are used to further differentiate the all-SEP and Chemical/Aerobrake options.

  10. Comet nucleus and asteroid sample return missions

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Three Advanced Design Projects have been completed this academic year at Penn State. At the beginning of the fall semester the students were organized into eight groups and given their choice of either a comet nucleus or an asteroid sample return mission. Once a mission had been chosen, the students developed conceptual designs. These were evaluated at the end of the fall semester and combined into three separate mission plans, including a comet nucleus same return (CNSR), a single asteroid sample return (SASR), and a multiple asteroid sample return (MASR). To facilitate the work required for each mission, the class was reorganized in the spring semester by combining groups to form three mission teams. An integration team consisting of two members from each group was formed for each mission so that communication and information exchange would be easier among the groups. The types of projects designed by the students evolved from numerous discussions with Penn State faculty and mission planners at the Johnson Space Center Human/Robotic Spacecraft Office. Robotic sample return missions are widely considered valuable precursors to manned missions in that they can provide details about a site's environment and scientific value. For example, a sample return from an asteroid might reveal valuable resources that, once mined, could be utilized for propulsion. These missions are also more adaptable when considering the risk to humans visiting unknown and potentially dangerous locations, such as a comet nucleus.

  11. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit, common return. 236.720 Section...

  12. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit, common return. 236.720 Section...

  13. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, common return. 236.720 Section...

  14. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit, common return. 236.720 Section...

  15. 49 CFR 236.720 - Circuit, common return.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Circuit, common return. A term applied where one wire is used for the return of more than one electric circuit. ... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, common return. 236.720 Section...

  16. MITIGATION CAPACITIES OF AGRICULTURAL DRAINAGE DITCHES FOR FERTILIZER CONTAMINATION FROM NO-TILL COTTON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are important routes of preferential flow in agricultural systems providing a rapid, more direct path for nutrient (N and P) laden drainage waters to reach downstream environments. Drainage ditches are forgotten links between agricultural farms and receiving waters, th...

  17. The 2011 Thailand flood: climate causes and return periods

    NASA Astrophysics Data System (ADS)

    Gale, Emma; Saunders, Mark

    2013-04-01

    Thailand is one of the most developed and wealthiest countries in Southeast Asia. However, its tropical location and the influence of seasonal monsoon rains and local topography make it prone to floods. The Thailand floods in 2011 were especially severe causing estimated losses of US 30 billion (economic) and US 12 billion (insured) (Swiss Re, 2012). This insured loss ranks easily as the highest ever worldwide from a freshwater flood disaster (Swiss Re, 2012). We review the nature, impacts and historical ranking of the 2011 Thailand flood, and then discuss the climate causes for the exceptional rainfall which triggered the flood - annual rainfall in 2011 was the highest in Thailand's 61-year precipitation record (Thai Meteorological Department, 2011). Thai precipitation data from 100 stations for the period 1992-2011, NCEP/NCAR mean sea level pressure (MSLP) data and best-track data from the Joint Typhoon Warning Center for the period 1992-2011 are used in this study. We find that the floods were caused by a combination of a strong Southeast Asian summer monsoon that brought high rainfall across the country between May and October, and by the remnants of four tropical storms that brought high rainfall to northern Thailand between June and October. During the monsoon season the Southern Oscillation was moderately positive and, as a result, likely contributed to the high monsoonal rains. We estimate the return periods for the 2011 Thai rains and compare these to satellite-derived return periods for 2011 Thai river flow. The rainfall return period varies from 8-20 years in the north and south of the country to 1-8 years in the east and centre of Thailand. Satellite-derived river flows at two locations on the Chao Phraya River suggest a return period of 10-20 years. The return period is also estimated using historical flood records (Brakenridge, 2012) which suggest a return period of 5-6 years. A 'consensus' return period for the 2011 Thai flood is estimated to be 10

  18. Facilities for Agricultural Education Curriculums.

    ERIC Educational Resources Information Center

    South Carolina State Dept. of Education, Columbia. Agricultural Education Section.

    Expansion of the vocational agriculture program to include education for off-farm agricultural occupations has placed increasing demands on existing facilities for agricultural programs. The facility requirements of the new curriculums are often not met by the existing facilities. Vocational agriculture teachers, state supervisory staff members,…

  19. 76 FR 49291 - Agricultural Swaps

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... Commission recently promulgated a final rule defining the term ``agricultural commodity.'' See 76 FR 41048... Agricultural Swaps, 76 FR 6095, February 3, 2011. \\8\\ See Agricultural Swaps, 75 FR 59666, Sept. 28, 2010. C... specifically addressing the costs and benefits of the proposed agricultural swaps rules. \\10\\ See NPRM, 76...

  20. Urban Agriculture Program Planning Guide.

    ERIC Educational Resources Information Center

    Hemp, Paul E.; Ethridge, Jim

    Urban agriculture may be defined as those areas of agriculture that are practiced in metropolitan settings, plus knowledge and skills in agricultural subject areas which lead to vocational proficiency and improved quality of life or effective citizenship. Agriculture areas that are especially significant in urban settings include ornamental…

  1. Theme: Changes in Agricultural Education.

    ERIC Educational Resources Information Center

    Agricultural Education Magazine, 1997

    1997-01-01

    Includes "Changes in Agricultural Education in Tennessee" (Byerley, Todd); "Evolving Focus for Agricultural Education Graduates?" (Schlink); "Researching Adult Organizations in Agricultural Education" (Seevers, Dormody); "Past 25 Years" (Klein, Luft); "Agricultural Education" (Sibiga, Mannebach); "Don't Look Back" (Butcher); "Changes in…

  2. Comet Odyssey: Comet Surface Sample Return

    NASA Astrophysics Data System (ADS)

    Weissman, Paul R.; Bradley, J.; Smythe, W. D.; Brophy, J. R.; Lisano, M. E.; Syvertson, M. L.; Cangahuala, L. A.; Liu, J.; Carlisle, G. L.

    2010-10-01

    Comet Odyssey is a proposed New Frontiers mission that would return the first samples from the surface of a cometary nucleus. Stardust demonstrated the tremendous power of analysis of returned samples in terrestrial laboratories versus what can be accomplished in situ with robotic missions. But Stardust collected only 1 milligram of coma dust, and the 6.1 km/s flyby speed heated samples up to 2000 K. Comet Odyssey would collect two independent 800 cc samples directly from the surface in a far more benign manner, preserving the primitive composition. Given a minimum surface density of 0.2 g/cm3, this would return two 160 g surface samples to Earth. Comet Odyssey employs solar-electric propulsion to rendezvous with the target comet. After 180 days of reconnaissance and site selection, the spacecraft performs a "touch-and-go” maneuver with surface contact lasting 3 seconds. A brush-wheel sampler on a remote arm collects up to 800 cc of sample. A duplicate second arm and sampler collects the second sample. The samples are placed in a return capsule and maintained at colder than -70 C during the return flight and at colder than -30 C during re-entry and for up to six hours after landing. The entire capsule is then refrigerated and transported to the Astromaterials Curatorial Facility at NASA/JSC for initial inspection and sample analysis by the Comet Odyssey team. Comet Odyssey's planned target was comet 9P/Tempel 1, with launch in December 2017 and comet arrival in June 2022. After a stay of 300 days at the comet, the spacecraft departs and arrives at Earth in May 2027. Comet Odyssey is a forerunner to a flagship Cryogenic Comet Sample Return mission that would return samples from deep below the nucleus surface, including volatile ices. This work was supported by internal funds from the Jet Propulsion Laboratory.

  3. Optimization of return electrodes in neurostimulating arrays

    NASA Astrophysics Data System (ADS)

    Flores, Thomas; Goetz, Georges; Lei, Xin; Palanker, Daniel

    2016-06-01

    Objective. High resolution visual prostheses require dense stimulating arrays with localized inputs of individual electrodes. We study the electric field produced by multielectrode arrays in electrolyte to determine an optimal configuration of return electrodes and activation sequence. Approach. To determine the boundary conditions for computation of the electric field in electrolyte, we assessed current dynamics using an equivalent circuit of a multielectrode array with interleaved return electrodes. The electric field modeled with two different boundary conditions derived from the equivalent circuit was then compared to measurements of electric potential in electrolyte. To assess the effect of return electrode configuration on retinal stimulation, we transformed the computed electric fields into retinal response using a model of neural network-mediated stimulation. Main results. Electric currents at the capacitive electrode-electrolyte interface redistribute over time, so that boundary conditions transition from equipotential surfaces at the beginning of the pulse to uniform current density in steady state. Experimental measurements confirmed that, in steady state, the boundary condition corresponds to a uniform current density on electrode surfaces. Arrays with local return electrodes exhibit improved field confinement and can elicit stronger network-mediated retinal response compared to those with a common remote return. Connecting local return electrodes enhances the field penetration depth and allows reducing the return electrode area. Sequential activation of the pixels in large monopolar arrays reduces electrical cross-talk and improves the contrast in pattern stimulation. Significance. Accurate modeling of multielectrode arrays helps optimize the electrode configuration to maximize the spatial resolution, contrast and dynamic range of retinal prostheses.

  4. Migratory beekeeping practices contribute insignificantly to transgenic pollen flow among fields of alfalfa produced for seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increased use of genetically engineered crops in agriculture has raised concerns over pollinator-mediated gene flow between transgenic and conventional agricultural varieties. This study evaluated whether contracted migratory beekeeping practices influence transgenic pollen flow among spatially iso...

  5. Land Grabbing and the Commodification of Agricultural Land in Africa

    NASA Astrophysics Data System (ADS)

    D'Odorico, P.; Rulli, M. C.

    2014-12-01

    The increasing global demand for farmland products is placing unprecedented pressure on the global agricultural system. The increasing demand can be met through either the intensification or the expansion of agricultural production at the expenses of other ecosystems. The ongoing escalation of large scale land acquisitions in the developing world may contribute to both of these two processes. Investments in agriculture have become a priority for a number of governments and corporations that are trying to expand their agricultural production while securing good profits. It is unclear however to what extent these investments are driving the intensification or the expansion of agriculture. In the last decade large scale land acquisitions by external investors have increased at unprecedented rates. This global land rush was likely enhanced by recent food crises, when prices skyrocketed in response to crop failure, new bioenergy policies, and the increasing demand for agricultural products by a growing and increasingly affluent human population. Corporations recognized the potential for high return investments in agricultural land, while governments started to enhance their food security by purchasing large tracts of land in foreign countries. It has been estimated that, to date, about 35.6 million ha of cropland - more than twice the agricultural land of Germany - have been acquired by foreign investors worldwide. As an effect of these land deals the local communities lose legal access to the land and its products. Here we investigate the effect of large scale land acquisition on agricultural intensification or expansion in African countries. We discuss the extent to which these investments in agriculture may increase crop production and stress how this phenomenon can greatly affect the local communities, their food security, economic stability and the long term resilience of their livelihoods, regardless of whether the transfer of property rights is the result of an

  6. AgBase: a functional genomics resource for agriculture

    PubMed Central

    McCarthy, Fiona M; Wang, Nan; Magee, G Bryce; Nanduri, Bindu; Lawrence, Mark L; Camon, Evelyn B; Barrell, Daniel G; Hill, David P; Dolan, Mary E; Williams, W Paul; Luthe, Dawn S; Bridges, Susan M; Burgess, Shane C

    2006-01-01

    Background Many agricultural species and their pathogens have sequenced genomes and more are in progress. Agricultural species provide food, fiber, xenotransplant tissues, biopharmaceuticals and biomedical models. Moreover, many agricultural microorganisms are human zoonoses. However, systems biology from functional genomics data is hindered in agricultural species because agricultural genome sequences have relatively poor structural and functional annotation and agricultural research communities are smaller with limited funding compared to many model organism communities. Description To facilitate systems biology in these traditionally agricultural species we have established "AgBase", a curated, web-accessible, public resource for structural and functional annotation of agricultural genomes. The AgBase database includes a suite of computational tools to use GO annotations. We use standardized nomenclature following the Human Genome Organization Gene Nomenclature guidelines and are currently functionally annotating chicken, cow and sheep gene products using the Gene Ontology (GO). The computational tools we have developed accept and batch process data derived from different public databases (with different accession codes), return all existing GO annotations, provide a list of products without GO annotation, identify potential orthologs, model functional genomics data using GO and assist proteomics analysis of ESTs and EST assemblies. Our journal database helps prevent redundant manual GO curation. We encourage and publicly acknowledge GO annotations from researchers and provide a service for researchers interested in GO and analysis of functional genomics data. Conclusion The AgBase database is the first database dedicated to functional genomics and systems biology analysis for agriculturally important species and their pathogens. We use experimental data to improve structural annotation of genomes and to functionally characterize gene products. AgBase is also

  7. Agricultural Meteorology in China.

    NASA Astrophysics Data System (ADS)

    Rosenberg, Norman J.

    1982-03-01

    During nearly five weeks in China (May-June 1981), the author visited scientific institutions and experiment stations engaged in agricultural meterology and climatology research and teaching. The facilities, studies, and research programs at each institution are described and the scientific work in these fields is evaluated. Agricultural meteorology and climatology are faced with some unique problems and opportunities in China and progress in these fields may be of critical importance to that nation in coming years. The author includes culinary notes and comments on protocol in China.

  8. Proceedings: Agricultural Technology Alliance

    SciTech Connect

    1997-09-01

    This report is a compilation of field trip overviews, presentations and committee reports from the EPRI-ATA meeting held in Boise, Idaho, May 28-30, 1997. The field trips consisted of an Agriculture and Aquaculture Tour, a tour of Idaho as America's Seed Supplier, and a Production of Milk, Cheese and Electricity tour. Presentations and committee reports include the following: (1) Idaho Seed Industry; (2) Controlled Environment Agriculture; (3) Irrigation in the North West: An Overview; (4) Drip Irrigation; (5) Sprinkler Irrigation; (6) Current Status of the ATA; (7) ATA Office Report; (8) Committee Reports; (9) Steering Committee Minutes.

  9. 7 CFR 42.123 - Flow diagram for skip lot sampling and inspection.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Flow diagram for skip lot sampling and inspection. 42.123 Section 42.123 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING... Procedures § 42.123 Flow diagram for skip lot sampling and inspection. EC02SE91.000 Notes: 1. Only...

  10. 7 CFR 42.123 - Flow diagram for skip lot sampling and inspection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Flow diagram for skip lot sampling and inspection. 42.123 Section 42.123 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING... Procedures § 42.123 Flow diagram for skip lot sampling and inspection. EC02SE91.000 Notes: 1. Only...

  11. 7 CFR 42.123 - Flow diagram for skip lot sampling and inspection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Flow diagram for skip lot sampling and inspection. 42.123 Section 42.123 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING... Procedures § 42.123 Flow diagram for skip lot sampling and inspection. EC02SE91.000 Notes: 1. Only...

  12. A spatial and seasonal description of return-levels for the Berlin-Brandenburg region (Germany)

    NASA Astrophysics Data System (ADS)

    Fischer, Madlen; Rust, Henning W.; Ulbrich, Uwe

    2016-04-01

    Extreme precipitation events have a strong impact on the environment, society and economy. Besides the direct effect, e.g. damage due to hail, extreme precipitation can cause flood events, mudslides and increased erosion, which in turn lead to serious damage. Typically, return levels derived from annual maxima of daily precipitation sums are used for the design of hydraulic structures or for risk assessment in insurance companies. Seasonally or monthly resolved return levels are rarely considered, although they provide additional information: the higher temporal resolution can be beneficial for risk management, e.g. for agriculture or tourism sector. In addition, annual return levels derived from monthly maxima offer lower uncertainties, since a larger data basis are used for estimation. Here, the generalized extreme value distribution (GEV) is used to calculate monthly resolved return levels for 323 stations in the region Berlin-Brandenburg (Germany). Instead of estimating the parameters of the GEV for each month separately, the seasonal variation is captured by harmonic functions. This natural approach is particularly suitable for an efficient characterization of the seasonal variation of extreme precipitation. In a first step, a statistical model is developed for each station separately to estimate the monthly return levels. Besides the seasonal smoothness, also smoothness in space is exploited here. We use functions of longitude, latitude and altitude to describe the spatial variation of GEV parameters in the second step. Thus, uncertainty is reduced at gauges with short time series and estimates for ungauged sites can be obtained in a meaningful way.

  13. IMPLEMENTATION OF AGRICULTURAL SALINITY CONTROL TECHNOLOGY IN GRAND VALLEY

    EPA Science Inventory

    A summary of the results of applied research on salinity control of irrigation return flows in the Grand Valley of Colorado is presented for the period of 1969 to 1976. Salinity and economic impacts are described for the Grand Valley Salinity Control Demonstration Project which c...

  14. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... employees of a contractor for purposes of programming, maintaining, repairing, or testing computer equipment... reproduction of returns or return information, the programming, maintenance, repair, or testing of equipment...

  15. Changes in Discharge in an Agricultural Watershed in Iowa: Modeling and Projections

    NASA Astrophysics Data System (ADS)

    Villarini, G.

    2014-12-01

    Our improved capability to adapt to future changes in discharge is unavoidably linked to our capability to predict the magnitude or at least the direction of these changes. The importance of improving discharge projections is particularly relevant in an agricultural state like Iowa. Iowa has been affected by a sequence of extreme events over the most recent years, with the flood events of 1993, 2008, 2010, 2013 and 2014 interrupted by the droughts of 2012 and summer 2013. It is clear that too much or too little water will have severe economic and societal impacts for this state, and the agricultural U.S. Midwest more generally. Therefore, being able to increase our confidence in the direction and magnitude of the projected changes in discharge (from low to high flow) will be of key importance for improving our mitigation and management strategies during both flooding and droughts. Here we focus on the Raccoon River at Van Meter, Iowa, and use a statistical approach to examine projected changes in discharge. We build on statistical models using rainfall and harvested corn and soybean acreage to explain the observed stream flow variability. We then use projections of these two predictors to examine the projected discharge response. Results are based on seven state-of-the-art global climate models (GCMs) produced under the Fifth Coupled Model Intercomparison Project (CMIP5), and two representative concentration pathways (RCPs 4.5 and 8.5). We find that there is not a strong signal of change in the discharge projections under the RCP 4.5. On the other hand, the results for the RCP 8.5 point to a stronger changing signal, in particular increasing trends in the upper part of the discharge distribution. Examination of two hypothetical agricultural scenarios indicates that these increasing trends could be potentially offset by decreasing the extent of the agricultural production. Finally, we discuss how to move forward with the concept of return period for engineering

  16. Goryachkin's agricultural mechanics

    NASA Astrophysics Data System (ADS)

    Chinenova, Vera

    2016-03-01

    The paper contributes to the development of applied mechanics by establishing a new discipline, namely, agricultural mechanics by academician Vasilii Prohorovich Goryachkin (1868-1935) who was an apprentice of Nikolay Yegorovich Zhukovsky and a graduate of the Moscow University (current known as Moscow State University) and the Imperial Higher Technical School.

  17. Agriculture. Dairy Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for dairy livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

  18. Agriculture. Beef Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for beef livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

  19. Agriculture Issues. Transition Series.

    ERIC Educational Resources Information Center

    Comptroller General of the U.S., Washington, DC.

    This report is one of a series by the General Accounting Office that summarizes major policy, management, and program issues facing agency heads in the Bush administration. Many concerns have been identified, some new, others long-standing. This report on the Department of Agriculture describes concerns about the following six issues: (1)…

  20. Agriculture Education. Farm Machinery.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in farm machinery. The guide presents units of study in the following areas: (1) small gas engines, (2) job opportunities, (3) tractors, (4) engines, (5) hydraulics, (6) electrical system, (7) combine…

  1. Vocational Agriculture II.

    ERIC Educational Resources Information Center

    Harp, Keith; Steward, Jim

    This curriculum guide was developed for second-year courses in vocational agriculture in Oklahoma. The curriculum contains 5 sections organized in 16 instructional units. The units follow a standard format established in 1970 for development of instructional materials for all Oklahoma vocational teachers. This format includes eight basic…

  2. Agriculture Education. Horticulture.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in ornamental horticulture. The guide presents units of study in the following areas: (1) horticulture and job opportunities, (2) preparing soil mixtures, (3) control, (4) plant propagation, (5) plant…

  3. AGRICULTURAL SIMULATION MODEL (AGSIM)

    EPA Science Inventory

    AGSIM is a large-scale econometric simulation model of regional crop and national livestock production in the United States. The model was initially developed to analyze the aggregate economic impacts of a wide variety issues facing agriculture, such as technological change, pest...

  4. Agriculture. Sheep Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for sheep, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task list. Each…

  5. Agricultural Education in Australia.

    ERIC Educational Resources Information Center

    Farquhar, R. N.

    This document is an English-language abstract (approximately 1,500 words) of a comprehensive survey of education and training for agriculture in Australia. The present facilities are described, and then set against estimates of present and future needs. Constructive proposals are made as to how these needs can best be met by agricultural…

  6. Nanotechnology in Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An overview is given of the application of nanotechnology to agriculture. This is an active field of R&D, where a large number of findings and innovations have been reported. For example, in soil management, applications reported include nanofertilizers, soil binders, water retention aids, and nut...

  7. Agriculture. Swine Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for swine, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task list. Each…

  8. Agriculture. Poultry Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for poultry, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task list.…

  9. Metrics for Agricultural Mechanics.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of agricultural mechanics students, this instructional package is one of four for the agribusiness and natural resources occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  10. [Vibration on agricultural tractors].

    PubMed

    Peretti, Alessandro; Delvecchio, Simone; Bonomini, Francesco; di Bisceglie, Anita Pasqua; Colosio, Claudio

    2013-01-01

    In the article, details related to the diffusion of agricultural tractors in Italy are given and considerations about the effects of vibration on operators, the sources of vibration and suggestions to reduce them are presented. The acceleration values observed in Italy amongst 244 tractors and levels of worker exposure are shown by means of histograms. The relevant data variability is discussed. PMID:24303716

  11. COMMUNITY SUPPORTED AGRICULTURE

    EPA Science Inventory

    NRMRL employees at the Air Pollution Prevention and Control Division in Research Triangle Park, North Carolina, are sharing in a unique community agriculture program that supports EPA environmental goals?off the job as well as on. Every Wednesday afternoon, bags of farm-fresh org...

  12. Agriculture, forestry, range resources

    NASA Technical Reports Server (NTRS)

    Macdonald, R. B.

    1974-01-01

    The necessary elements to perform global inventories of agriculture, forestry, and range resources are being brought together through the use of satellites, sensors, computers, mathematics, and phenomenology. Results of ERTS-1 applications in these areas, as well as soil mapping, are described.

  13. Curriculum Guide for Agriculture.

    ERIC Educational Resources Information Center

    Oregon State Board of Education, Salem. Div. of Community Colleges and Career Education.

    Developed through a cooperative effort by industry and education, this curriculum guide outlines the basic knowledge and skills necessary for entry-level competencies in the broad field of agriculture, or for entrance into a post-high school program. This guide is one of several developed for Oregon's new approach to secondary education called…

  14. Teaching Traditional Tropical Agriculture.

    ERIC Educational Resources Information Center

    Clawson, David L.

    1987-01-01

    Maintains that the teaching of traditional tropical agriculture through the presentation of large numbers of categories or types tends to overemphasize superficial differences at the expense of comprehending the inner essence of life as it exists for the majority of the world's farmers. Offers an alternative approach which claims to foster greater…

  15. Agricultural lung diseases.

    PubMed Central

    Kirkhorn, S R; Garry, V F

    2000-01-01

    Agriculture is considered one of the most hazardous occupations. Organic dusts and toxic gases constitute some of the most common and potentially disabling occupational and environmental hazards. The changing patterns of agriculture have paradoxically contributed to both improved working conditions and increased exposure to respiratory hazards. Animal confinement operations with increasing animal density, particularly swine confinement, have contributed significantly to increased intensity and duration of exposure to indoor air toxins. Ongoing research has implicated bacterial endotoxins, fungal spores, and the inherent toxicity of grain dusts as causes of upper and lower airway inflammation and as immunologic agents in both grain and animal production. Animal confinement gases, particularly ammonia and hydrogen sulfide, have been implicated as additional sources of respiratory irritants. It has become evident that a significant percentage of agricultural workers have clinical symptoms associated with long-term exposure to organic dusts and animal confinement gases. Respiratory diseases and syndromes, including hypersensitivity pneumonitis, organic dust toxic syndrome, chronic bronchitis, mucous membrane inflammation syndrome, and asthmalike syndrome, result from ongoing acute and chronic exposures. In this review we focus upon the emerging respiratory health issues in a changing agricultural economic and technologic environment. Environmental and occupational hazards and exposures will be emphasized rather than clinical diagnosis and treatment. Methods of prevention, from both engineering controls and personal respiratory perspectives, are also addressed. PMID:10931789

  16. Microcomputer Applications in Agriculture.

    ERIC Educational Resources Information Center

    Hilgenberg, Gene; And Others

    This curriculum guide is intended to assist persons teaching a course in microcomputer applications in agriculture. (These applications are designed to be used on Apple IIe or TRS-80 microcomputers.) Addressed in the individual units of instruction are the following topics: microcomputer operating procedures; procedures for evaluating and…

  17. Urban conservation agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetables are important sources of vitamins and nutrients for human nutrition. United States Department of Agriculture recommends filling half of the food plates with vegetables in every meal. While it is important in promoting good health, access to fresh vegetables is limited especially in urban ...

  18. Agriculture: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This guide, which was written as an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System, outlines the suggested scope and sequence of a 3-year program in agriculture. The guide consists of a course description; general course objectives;…

  19. Effect of Weather on Agricultural Futures Markets on the Basis of DCCA Cross-Correlation Coefficient Analysis

    NASA Astrophysics Data System (ADS)

    Cao, Guangxi; He, Cuiting; Xu, Wei

    2016-03-01

    This study investigates the correlation between weather and agricultural futures markets on the basis of detrended cross-correlation analysis (DCCA) cross-correlation coefficients and q-dependent cross-correlation coefficients. In addition, detrended fluctuation analysis (DFA) is used to measure extreme weather and thus analyze further the effect of this condition on agricultural futures markets. Cross-correlation exists between weather and agricultural futures markets on certain time scales. There are some correlations between temperature and soybean return associated with medium amplitudes. Under extreme weather conditions, weather exerts different influences on different agricultural products; for instance, soybean return is greatly influenced by temperature, and weather variables exhibit no effect on corn return. Based on the detrending moving-average cross-correlation analysis (DMCA) coefficient and DFA regression results are similar to that of DCCA coefficient.

  20. Where Are "Women Returners" Returning From? Deconstructing Domestication in the Context of Lifelong Learning.

    ERIC Educational Resources Information Center

    Clarke, Julia

    The question of where "women returners" to education are returning from was examined through an exploration of the life histories of 18 women in southern England. The study focused on the biographies of women who regarded themselves as primarily responsible for the care of others and yet whose aspirations involved some form of continuing…

  1. 78 FR 26506 - Disclosure of Returns and Return Information to Designee of Taxpayer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-07

    ... Internal Revenue Service 26 CFR Part 301 RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Final regulations. SUMMARY... proposed rulemaking (REG-153338-09) in the Federal Register, 76 FR 14827, on March 18, 2011, which...

  2. 76 FR 31543 - Disclosure of Returns and Return Information to Designee of Taxpayer; Hearing Cancellation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ... Internal Revenue Service 26 CFR Part 301 RIN 1545-BJ19 Disclosure of Returns and Return Information to Designee of Taxpayer; Hearing Cancellation AGENCY: Internal Revenue Service (IRS), Treasury. ACTION... (76 FR 14827) announced that a public hearing was scheduled for June 9, 2011, at 10 a.m. in the...

  3. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  4. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  5. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 false Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  6. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 false Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  7. 27 CFR 479.151 - Failure to make returns: Substitute returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true Failure to make returns: Substitute returns. 479.151 Section 479.151 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS,...

  8. Return Migration: A Study of College Graduates Returning to Rural U.S. Homes

    ERIC Educational Resources Information Center

    Mahoney, Elizabeth D.

    2009-01-01

    The purpose of this study is to explore perceptions of return migration experiences and gain knowledge from rural residents who have left to obtain a college education and start careers in non-rural areas, and who then returned to their rural hometowns with the social and economic benefits of a college education, and other valuable resources. This…

  9. Return to Play After Cervical Disc Surgery.

    PubMed

    Kang, Daniel G; Anderson, Justin C; Lehman, Ronald A

    2016-10-01

    Criteria for return to sports and athletic activities after cervical spine surgery are unclear. There is limited literature regarding the outcomes and optimal criteria. Determining return to play criteria remains a challenge and continues to depend on the experience and good judgment of the treating surgeon. There is strong consensus in the literature, despite lack of evidence-based data, that athletes after single-level anterior cervical discectomy and fusion (ACDF) may safely return to collision and high-velocity sports. The athlete should be counseled and managed on a case-by-case basis, taking into consideration the type of sport, player-specific variables, and type of surgery performed. PMID:27543397

  10. SOCCER: Comet Coma Sample Return Mission

    NASA Technical Reports Server (NTRS)

    Albee, A. L.; Uesugi, K. T.; Tsou, Peter

    1994-01-01

    Comets, being considered the most primitive bodies in the solar system, command the highest priority among solar system objects for studying solar nebula evolution and the evolution of life through biogenic elements and compounds. Sample Of Comet Coma Earth Return (SOCCER), a joint effort between NASA and the Institute of Space and Astronautical Science (ISAS) in Japan, has two primary science objectives: (1) the imaging of the comet nucleus and (2) the return to Earth of samples of volatile species and intact dust. This effort makes use of the unique strengths and capabilities of both countries in realizing this important quest for the return of samples from a comet. This paper presents an overview of SOCCER's science payloads, engineering flight system, and its mission operations.

  11. Planetary Protection Technology for Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Gershman, Robert

    2005-01-01

    The NASA Mars Exploration Program has recently adopted a plan that includes a first Mars sample return (MSR) mission proposed for launch in 2013. Such a mission would deal with two new categories of planetary protection requirements: (1) assuring a very low probability of inadvertent release of the sample in order to provide extra protection against the extremely unlikely possibility of biological hazards in the returned material and (2) keeping the samples free of round-trip Earth organisms to facilitate confirmation of safety after return to Earth. This paper describes the planetary-protection-related technical challenges awaiting any MSR mission and describes work in progress on technology needed to meet these challenges. New technology is needed for several functions. Containment assurance requires breaking the chain of contact with Mars: the exterior of the sample container must not be contaminated with Mars material either during the loading process or during launch from the Mars surface.

  12. The Hayabusa Spacecraft Sample Return Mission

    NASA Technical Reports Server (NTRS)

    Abell, Paul A.

    2010-01-01

    The Hayabusa (originally known as MUSES-C) engineering spacecraft was launched by the 5th Mu V launch vehicle on May 9, 2003 by the Japan Aerospace Exploration Agency (JAXA). It was designed to acquire samples from the surface of near-Earth asteroid 25143 Itokawa (1998 SF36) and return them to Earth. The main objectives of the mission were to demonstrate the performance of various technologies such as ion engine performance, autonomous navigation and control, asteroid surface sampling, and recovery of the return capsule after high speed re-entry. Hayabusa successfully returned a small capsule to Earth in June 2010 with a parachute assisted landing in Woomera, Australia. Details of the Hayabusa mission and the recovery operation will be presented for discussion.

  13. Earth Entry Vehicle for Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Mitcheltree, R. A.; Braun, R. D.; Hughes. S. J.; Simonsen, L. C.

    2000-01-01

    The driving requirement for design of a Mars Sample return mission is assuring containment of the returned samples. The impact of this requirement on developmental costs, mass allocation, and design approach of the Earth Entry Vehicle is significant. A simple Earth entry vehicle is described which can meet these requirements and safely transport the Mars Sample Return mission's sample through the Earth's atmosphere to a recoverable location on the surface. Detailed analysis and test are combined with probabilistic risk assessment to design this entirely passive concept that circumvents the potential failure modes of a parachute terminal descent system. The design also possesses features that mitigate other risks during the entry, descent, landing and recovery phases. The results of a full-scale drop test are summarized.

  14. Stakeholder views on returning research results.

    PubMed

    Haga, Susanne B; Zhao, Jennifer Q

    2013-01-01

    While the disclosure of research findings is relevant to all types of biomedical research, it has garnered particular attention with respect to genetics and genomics research due to some of the unique aspects of the data and the high public profile of the field. In this chapter, we review the attitudes of stakeholders (research participants, policymakers, and researchers) to define areas of consensus regarding the issue of returning research results across and within groups. In addition to stakeholder attitudes about obligations and interest in research results, other major related issues related to returning research results, such as informed consent, communication of research results, and cost, are discussed. Given the consensus between stakeholders to return summary reports of a study's outcomes and individual research results of clinical significance, we conclude that the time has come to encourage, if not require, researchers to consider these issues in the developmental planning stages of a project and to plan and budget accordingly. PMID:24262096

  15. Planetary protection issues for sample return missions.

    PubMed

    DeVincenzi, D L; Klein, H P

    1989-01-01

    Sample return missions from a comet nucleus and the Mars surface are currently under study in the US, USSR, and by ESA. Guidance on Planetary Protection (PP) issues is needed by mission scientists and engineers for incorporation into various elements of mission design studies. Although COSPAR has promulgated international policy on PP for various classes of solar system exploration missions, the applicability of this policy to sample return missions, in particular, remains vague. In this paper, we propose a set of implementing procedures to maintain the scientific integrity of these samples. We also propose that these same procedures will automatically assure that COSPAR-derived PP guidelines are achieved. The recommendations discussed here are the first step toward development of official COSPAR implementation requirements for sample return missions. PMID:11537373

  16. The Agricultural Health Study.

    PubMed Central

    Alavanja, M C; Sandler, D P; McMaster, S B; Zahm, S H; McDonnell, C J; Lynch, C F; Pennybacker, M; Rothman, N; Dosemeci, M; Bond, A E; Blair, A

    1996-01-01

    The Agricultural Health Study, a large prospective cohort study has been initiated in North Carolina and Iowa. The objectives of this study are to: 1) identify and quantify cancer risks among men, women, whites, and minorities associated with direct exposure to pesticides and other agricultural agents; 2) evaluate noncancer health risks including neurotoxicity reproductive effects, immunologic effects, nonmalignant respiratory disease, kidney disease, and growth and development among children; 3) evaluate disease risks among spouses and children of farmers that may arise from direct contact with pesticides and agricultural chemicals used in the home lawns and gardens, and from indirect contact, such as spray drift, laundering work clothes, or contaminated food or water; 4) assess current and past occupational and nonoccupational agricultural exposures using periodic interviews and environmental and biologic monitoring; 5) study the relationship between agricultural exposures, biomarkers of exposure, biologic effect, and genetic susceptibility factors relevant to carcinogenesis; and 6) identify and quantify cancer and other disease risks associated with lifestyle factors such as diet, cooking practices, physical activity, smoking and alcohol consumption, and hair dye use. In the first year of a 3-year enrollment period, 26,235 people have been enrolled in the study, including 19,776 registered pesticide applicators and 6,459 spouses of registered farmer applicators. It is estimated that when the total cohort is assembled in 1997 it will include approximately 75,000 adult study subjects. Farmers, the largest group of registered pesticide applicators comprise 77% of the target population enrolled in the study. This experience compares favorably with enrollment rates of previous prospective studies. Images Figure 1. Figure 2. Figure 3. Figure 4. PMID:8732939

  17. Medical returns as class transformation: situating migrants' medical returns within a framework of transnationalism.

    PubMed

    Horton, Sarah B

    2013-01-01

    Because studies of migrants' 'medical returns' have been largely confined to the field of public health, such forms of return migration are rarely contextualized within the rich social scientific literature on transnational migration. Drawing on ethnographic interviews with Mexican migrants in an immigrant enclave in central California, I show that migrants' reasons for returning to their hometowns for care must be understood within the class disjunctures facilitated by migration. While migrants' Medicaid insurance confined them to public clinics and hospitals in the United States, their migrant dollars enabled them to visit private doctors and clinics in Mexico. Yet medical returns were not mere medical arbitrage, but also allowed migrants to access care that had previously been foreclosed to them as poor peasants in Mexico. Thus crossing the border enabled a dual class transformation, as Mexican migrants transitioned from Medicaid recipients to cash-paying patients, and from poor rural peasants to 'returning royalty.' PMID:23944244

  18. Horizontal fields generated by return strokes

    NASA Technical Reports Server (NTRS)

    Cooray, Vernon

    1991-01-01

    Horizontal fields generated by return strokes play an important role in the interaction of lightning generated electric fields with power lines. In many of the recent investigations on the interaction of lightning electromagnetic fields with power lines, the horizontal field was calculated by employing the expression for the tilt of the electric field of a plane wave propagating over finitely conducting earth. The method is suitable for calculating horizontal fields generated by return strokes at distances as close as 200m. At these close ranges, the use of the wavetilt expression can cause large errors.

  19. Cerebral vascular reactivity on return from the International Space Station

    NASA Astrophysics Data System (ADS)

    Zuj, Kathryn; Greaves, Danielle; Shoemaker, Kevin; Blaber, Andrew; Hughson, Richard L.

    Returning from spaceflight, astronauts experience a high incidence of orthostatic intolerance and syncope. Longer duration space flight may result in greater adaptations to microgravity which could increase the post-flight incidence of syncope. CCISS (Cardiovascular and Cerebovascular Control on return from the International Space Station) is an ongoing project designed to help determine adaptations that occur during spaceflight which may contribute to orthostatic intolerance. One component of this project involves looking at cerebral vascular responses before and after long duration spaceflight. As a known vasodilator, carbon dioxide (CO2) has been frequently used to assess changes in cerebral vascular reactivity. In this experiment, end tidal PCO2 was manipulated through changes in respired air. Two breaths of a 10% CO2 gas mixture were administered at 1-min intervals resulting in an increase in end tidal PCO2 . Throughout the testing, cerebral blood flow velocity (CBFV) was determined using transcranial Doppler ultrasound. The cerebral resistance index (RI) was calculated from the Doppler wave form using the equation; RI=(CBFVsystolic-CBFVdiastolic)/CBFVsystolic. Changes in this index have been shown to reflect changes in cerebral vascular resistance. Peak responses to the CO2 stimulus were determined and compared to baseline measures taken at the beginning of the testing. Cerebral blood flow velocity increased and RI decreased with the two breaths of CO2. Preliminary data show a 36.0% increase in CBFV and a 9.0% decrease in RI pre-flight. Post flight, the response to CO2 appears to change showing a potentially blunted decrease in resistance (6.8%) and a smaller increase in CBFV (22.8%). Long term spaceflight may result in cerebrovascular changes which could decrease the vasodilatory capacity of cerebral resistance vessels. Further investigations in the CCISS project will reveal the interactive role of CO2 and arterial blood pressure on maintenance of brain

  20. Flow line sampler

    DOEpatents

    Nicholls, Colin I.

    1992-07-14

    An on-line product sampling apparatus and method for measuring product samples from a product stream (12) in a flow line (14) having a sampling aperture (11), includes a sampling tube (18) for containing product samples removed from flow line (14). A piston (22) removes product samples from the product stream (12) through the sampling aperture (11) and returns samples to product stream (12). A sensor (20) communicates with sample tube (18), and senses physical properties of samples while the samples are within sample tube (18). In one embodiment, sensor (20) comprises a hydrogen transient nuclear magnetic resonance sensor for measuring physical properties of hydrogen molecules.

  1. Fuel cell with internal flow control

    DOEpatents

    Haltiner, Jr., Karl J.; Venkiteswaran, Arun

    2012-06-12

    A fuel cell stack is provided with a plurality of fuel cell cassettes where each fuel cell cassette has a fuel cell with an anode and cathode. The fuel cell stack includes an anode supply chimney for supplying fuel to the anode of each fuel cell cassette, an anode return chimney for removing anode exhaust from the anode of each fuel cell cassette, a cathode supply chimney for supplying oxidant to the cathode of each fuel cell cassette, and a cathode return chimney for removing cathode exhaust from the cathode of each fuel cell cassette. A first fuel cell cassette includes a flow control member disposed between the anode supply chimney and the anode return chimney or between the cathode supply chimney and the cathode return chimney such that the flow control member provides a flow restriction different from at least one other fuel cell cassettes.

  2. 75 FR 14539 - Furnishing Identifying Number of Tax Return Preparer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-26

    ...This document contains proposed regulations under section 6109 of the Internal Revenue Code (Code) that provide guidance to tax return preparers on furnishing an identifying number on tax returns and claims for refund of tax that they prepare. These proposed regulations provide guidance on the identifying number of a tax return preparer for tax returns and claims for refund filed before and......

  3. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  4. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  5. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  6. 26 CFR 31.6011(a)-6 - Final returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... person filing a final return (other than a final return on Form 942 or Form 943) must furnish information... return, and such person shall furnish information showing the date of the last payment of taxable... make a return on a particular form pursuant to § 31.6011(a)-1, § 31.6011(a)-4, or § 31.6011(a)-5,...

  7. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  8. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  9. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  10. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES (CONTINUED) Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses...

  11. 26 CFR 1.6013-1 - Joint returns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint returns. 1.6013-1 Section 1.6013-1...) INCOME TAXES Tax Returns Or Statements § 1.6013-1 Joint returns. (a) In general. (1) A husband and wife may elect to make a joint return under section 6013(a) even though one of the spouses has no...

  12. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  13. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  14. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  15. 26 CFR 301.6501(e)-1 - Omission from return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... taxes. (i) If a private foundation omits from its annual return with respect to the tax imposed by... after the return was filed. If a private foundation discloses in its return (or in a schedule or... foundation has omitted more than 25 percent of the tax reported on its return. (ii) If a private...

  16. Agricultural trade and the global phosphorus cycle

    NASA Astrophysics Data System (ADS)

    Schipanski, M.; Bennett, E.; Riskin, S.; Porder, S.

    2012-12-01

    Trends of increasing agricultural trade, increased concentration of livestock production systems, and increased human consumption of livestock products influence the distribution of nutrients across the global landscape. Phosphorus (P) represents a unique management challenge as we are rapidly depleting mineable reserves of this essential and non-renewable resource. At the same time, its overuse can lead to pollution of aquatic ecosystems. We analyzed the relative contributions of food crop, feed crop, and livestock product trade to P flows through agricultural soils for twelve countries from 1961 to 2007. We then used case studies of P fertilizer use in the world's three major soybean export regions: Iowa (USA), Mato Grosso (Brazil), and Buenos Aires (Argentina) to examine the influence of historical P management and soil types on agriculture's environmental consequences. Due to the intensification of agricultural production, average soil surface P balances more than tripled from 6 to 21 kg P per ha between 1961 and 2007 for the twelve study countries. Consequently, countries that are primarily agricultural exporters carried increased risks for water pollution or, for Argentina, reduced soil fertility due to soil P mining to support exports. In 2007, nations imported food and feed from regions with higher apparent P fertilizer use efficiencies than if those crops were produced domestically. However, this was largely because imports were sourced from regions depleting soil P resources to support export crop production. In addition, the pattern of regional specialization and intensification of production systems also reduced the potential to recycle P resources, with greater implications for livestock production than crop production. In a globalizing world, it will be increasingly important to integrate biophysical constraints of our natural resources and environmental impacts of agricultural systems into trade policy and agreements and to develop mechanisms that

  17. Reality Check: A Teacher Educator Returns Home

    ERIC Educational Resources Information Center

    Scherff, Lisa; Kaplan, Jeff

    2006-01-01

    This collaborative self-study, told through email excerpts and reflections, explores a teacher educator's return to high school teaching. In this study, we juxtapose our voices and alternate between past and present to develop insights that reveal how going back can lead to moving forward with respect to educating prospective teachers. While the…

  18. There's Little Return for Attentional Momentum

    ERIC Educational Resources Information Center

    Snyder, Janice J.; Schmidt, William C.; Kingstone, Alan

    2009-01-01

    Inhibition of return (IOR) refers to a delay in response time (RT) to targets appearing at a previously cued location. The prevailing view is that IOR reflects visual-motor inhibition. The "attentional momentum" account rejects this idea, and instead proposes that IOR reflects an automatic shift of attention away from the cued location resulting…

  19. Mars Sample Return from Meridiani Planum

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.

    2008-01-01

    The NASA Mars Exploration Program has four main goals: (i) determine if life ever arose there, (ii) understand the processes and history of its climate, (iii) determine the evolution of its surface and interior, and (iv) prepare for human exploration of Mars. These goals are embodied in the NASA Mars exploration strategy Follow the Water. Current Mars exploration tactics for lander missions build on knowledge gained by prior orbital investigations; the science rationale for choosing landing sites is based on the current best interpretation of the geology. A future Mars sample return mission will greatly exceed in cost typical lander missions because of the need to design for return to Earth and the infrastructure needed on Earth to curate and process the samples safely and cleanly. Because of this added cost burden, expectations for science return are higher. There must be some prospect that the returned samples will allow for testing higher level hypotheses relevant to NASA's goals. Site selection must be based on knowledge gained from prior in situ measurements to enhance the prospects for successfully meeting these goals. I will argue that Meridiani Planum should be that site.

  20. A Sample Return Container with Hermetic Seal

    NASA Technical Reports Server (NTRS)

    Kong, Kin Yuen; Rafeek, Shaheed; Sadick, Shazad; Porter, Christopher C.

    2000-01-01

    A sample return container is being developed by Honeybee Robotics to receive samples from a derivative of the Champollion/ST4 Sample Acquisition and Transfer Mechanism or other samplers and then hermetically seal samples for a sample return mission. The container is enclosed in a phase change material (PCM) chamber to prevent phase change during return and re-entry to earth. This container is designed to operate passively with no motors and actuators. Using the sampler's featured drill tip for interfacing, transfer-ring and sealing samples, the container consumes no electrical power and therefore minimizes sample temperature change. The circular container houses a few isolated canisters, which will be sealed individually for samples acquired from different sites or depths. The drill based sampler indexes each canister to the sample transfer position, below the index interface for sample transfer. After sample transfer is completed, the sampler indexes a seal carrier, which lines up seals with the openings of the canisters. The sampler moves to the sealing interface and seals the sample canisters one by one. The sealing interface can be designed to work with C-seals, knife edge seals and cup seals. Again, the sampler provides all sealing actuation. This sample return container and co-engineered sample acquisition system are being developed by Honeybee Robotics in collaboration with the JPL Exploration Technology program.