Science.gov

Sample records for production cycle argentine

  1. Hydrological cycles and trends in the NW Argentine Andes since 1940

    NASA Astrophysics Data System (ADS)

    Castino, Fabiana; Bookhagen, Bodo; Strecker, Manfred

    2016-04-01

    Strong spatiotemporal variability characterizes the hydrometeorological pattern in the NW Argentine Andes, draining parts of the most populated and economically important areas of South America. During the summer monsoon season (DJF), the eastern flanks of the central Andes are characterized by deep convection, exposing them to extreme hydrometeorological events. These often result in floods and landslides with disastrous effects on the local populations. Here, we analyze river discharge to explore long-term hydrological variability in NW Argentine Andes and the linked climate controlling processes. We rely on 13 daily river discharge time series relevant to drainage basins spanning several size orders (102-104 km2) starting in 1914 and define different hydro-climate indices both for the mean and the extreme hydrological events. We apply quantile regression to investigate long-term trends and spectral analysis associated with cross-correlation with SST-based climate indices to identify links to large-scale climate variability modes. River discharge presents a pronounced and coherent variability signal in South America, particularly for wide drainage basins, such as the Amazon and Paraná/La Plata rivers, strongly associated to Pacific and Atlantic Oceans Sea Surface Temperature (SST) anomalies (i.e. ENSO, PDO, AMO). Our analysis evidences that in the NW Argentine Andes, mean discharge values are characterized by statistically significant, mostly positive, long-term trends since 1940, whereas the extreme events present a more non-unidirectional trend pattern. Also, coherent multi-annual to multi-decadal cycles characterizing the discharge pattern have been identified, suggesting that processes linked to SST anomaly-modes strongly control the hydrometeorology variability in the NW Argentina Andes.

  2. Adaptation to Interannual and Interdecadal Climate Variability in Agricultural Production Systems of the Argentine Pampas

    NASA Astrophysics Data System (ADS)

    Podestá, G. P.; Bert, F.; Weber, E.; Laciana, C.; Rajagopalan, B.; Letson, D.

    2007-05-01

    Agricultural ecosystems play a central role in world food production and food security, and involve one of the most climate-sensitive sectors of society-agriculture. We focus on crop production in the Argentine Pampas, one of the world's major agricultural regions. Climate of the Pampas shows marked variability at both interannual and decadal time scales. We explored the scope for adaptive management in response to climate information on interannual scales. We show that different assumptions about what decision makers are trying to achieve (i.e., their objective functions) may change what actions are considered as "optimal" for a given climate context. Optimal actions also were used to estimate the economic value of forecasts of an ENSO phase. Decision constraints (e.g., crop rotations) have critical influence on value of the forecasting system. Gaps in knowledge or misconceptions about climate variability were identified in open-ended "mental model" interviews. Results were used to design educational interventions. A marked increase in precipitation since the 1970s, together with new production technologies, led to major changes in land use patterns in the Pampas. Continuous cropping has widely replaced agriculture-pasture rotations. Nevertheless, production systems that evolved partly in response to increased rainfall may not be viable if climate reverts to a drier epoch. We use historical data to define a range of plausible climate trajectories 20-30 years hence. Regional scenarios are downscaled using semi-parametric weather generators to produce multiple realizations of daily weather consistent with decadal scenarios. Finally, we use the synthetic climate, crop growth models, and realistic models of decision-making under risk to compute risk metrics (e.g., probability of yields or profits being below a threshold). Climatically optimal and marginal locations show differential responses: probabilities of negative economic results are much higher in currently

  3. Selection of the Argentine indicator region

    NASA Technical Reports Server (NTRS)

    Ramirez, C. J.; Reed, C. R. (Principal Investigator)

    1982-01-01

    Determined from available Argentine crop statistics, selection of the Indicator Region was based on the highest wheat, corn, and soybean producing provinces, which were: Buenos Aires, Cordoba, Entre Rios, and Santa Fe. Each province in Argentina was examined for the availability of LANDSAT data; area, yield and production statistics; crop calendars; and other ancillary data. The Argentine Indicator Region is described.

  4. Contemporary Argentine Cinema during Neoliberalism

    ERIC Educational Resources Information Center

    Rocha, Carolina

    2009-01-01

    In this article I analyze contemporary Argentine cinematic production assessing the impact of Law 24,377 that was implemented in 1995 and that provided much-needed funds for national productions. By looking at film production and consumption, the emergence of young filmmakers and the performance of both commercial films and those belonging to the…

  5. Salvadora persica agro-ecological suitability for oil production in Argentine dryland salinity.

    PubMed

    Falasca, Silvia; Pitta-Alvarez, Sandra; del Fresno, Carolina Miranda

    2015-12-15

    One of the major causes of crop stress is soil or water salinity. Thus, selection of the best species for cultivation in semiarid and arid climates is fundamental. Salvadora persica is an evergreen perennial halophyte that can grow under extreme conditions, from very dry environments to highly saline soils. Based on international bibliography, the authors outlined an agro-ecological zoning model to determine the potential cultivation zones for S. persica in Argentina. This model may be applied to any part of the world, using the agro-ecological limits presented in this work. All the maps were developed by the implementation of a geographic information system (GIS) that can be updated by the further incorporation of complementary information, with the consequent improvement of the original database. The overlap of the agroclimatic suitability map on the drylands' saline soils and the drylands' alkaline soils maps, determined the agro-ecological zoning. Since some areas in the agro-ecological zoning can overlap with land that is already assigned for other uses, protected areas, current land use/cover of the different zones, and urban areas maps were incorporated into the GIS and subtracted by a mask. This resulted in the delimitation of "potential cultivation zoning", thus avoiding possible conflicts surrounding the use of land and making the agro-ecological zonation more efficient. There is a broad agro-ecological zone for cultivation of S. persica that extends from Northern Argentina to approximately 41° South latitude, under dry-subhumid to semiarid climates. Lands classified with different degrees of suitability in the potential cultivation zoning could be used for production of this species for energy purposes on lands that are either unsuitable for food production or currently assigned for other purposes. This paper represents pioneering work since there are no previous studies concerning the introduction of S. persica in Argentina.

  6. Salvadora persica agro-ecological suitability for oil production in Argentine dryland salinity.

    PubMed

    Falasca, Silvia; Pitta-Alvarez, Sandra; del Fresno, Carolina Miranda

    2015-12-15

    One of the major causes of crop stress is soil or water salinity. Thus, selection of the best species for cultivation in semiarid and arid climates is fundamental. Salvadora persica is an evergreen perennial halophyte that can grow under extreme conditions, from very dry environments to highly saline soils. Based on international bibliography, the authors outlined an agro-ecological zoning model to determine the potential cultivation zones for S. persica in Argentina. This model may be applied to any part of the world, using the agro-ecological limits presented in this work. All the maps were developed by the implementation of a geographic information system (GIS) that can be updated by the further incorporation of complementary information, with the consequent improvement of the original database. The overlap of the agroclimatic suitability map on the drylands' saline soils and the drylands' alkaline soils maps, determined the agro-ecological zoning. Since some areas in the agro-ecological zoning can overlap with land that is already assigned for other uses, protected areas, current land use/cover of the different zones, and urban areas maps were incorporated into the GIS and subtracted by a mask. This resulted in the delimitation of "potential cultivation zoning", thus avoiding possible conflicts surrounding the use of land and making the agro-ecological zonation more efficient. There is a broad agro-ecological zone for cultivation of S. persica that extends from Northern Argentina to approximately 41° South latitude, under dry-subhumid to semiarid climates. Lands classified with different degrees of suitability in the potential cultivation zoning could be used for production of this species for energy purposes on lands that are either unsuitable for food production or currently assigned for other purposes. This paper represents pioneering work since there are no previous studies concerning the introduction of S. persica in Argentina. PMID:26348151

  7. Product development cycle time reduction

    NASA Astrophysics Data System (ADS)

    Farran, Robin

    1992-05-01

    We are facing here today the key issues that face us in the competitive environment. North American companies are struggling to compete in the global marketplace. Gone are the days when presence ensured success. Then, sales and earnings were guaranteed. Today the competition is intense. Many manufacturing and service companies are no longer competitive. Traditionally, manufacturing companies have created the most wealth for the community and economy. Losing this ability to create wealth is tragic and unnecessary. A company can only be successful by focusing on customer satisfaction at competitive costs. Revenue growth and earnings growth require a continuous stream of products that anticipate the customers' needs, result from shorter and shorter innovation cycles, continually improve in quality, and are produced at improved costs on each cycle. The best opportunities for increased quality and decreased costs are with new products. Sure, work on quality and costs everyday. The biggest changes, however, will come through the new product development cycle. We must improve our development processes to provide leadership products which result in high levels of customer satisfaction. This is a prerequisite for business success. When presence in the marketplace was a virtual guarantee of success for a North American company, technology tended to drive the products, and the customers bought virtually everything that was produced. Functional excellence was stressed within companies ... and that was enough. Effective planning processes were not a prerequisite for success. Today success demands highly developed business research and planning processes, and functional excellence combined with organizational capabilities that ensure commercialization excellence.

  8. The agro-ecological suitability of Atriplex nummularia and A. halimus for biomass production in Argentine saline drylands

    NASA Astrophysics Data System (ADS)

    Falasca, Silvia Liliana; Pizarro, María José; Mezher, Romina Nahir

    2014-09-01

    The choice of the best species to cultivate in semi-arid and arid climates is of fundamental importance, and is determined by many factors, including temperature and rainfall, soil type, water availability for irrigation and crop purposes. Soil or water salinity represents one of the major causes of crop stress. Species of the genus Atriplex are characterized by high biomass productivity, high tolerance to drought and salinity, and high efficiency in use of solar radiation and water. Based on a search of the international literature, the authors outline an agro-climatic zoning model to determine potential production areas in Argentina for Atriplex halimus and Atriplex numularia. Using the agroclimatic limits presented in this work, this model may be applied to any part of the world. When superimposed on the saline areas map, the agroclimatic map shows the suitability of agro-ecological zoning for both species for energy purposes on land unsuitable for food production. This innovative study was based on the implementation of a geographic information system that can be updated by further incorporation of complementary information, with consequent improvement of the original database.

  9. Fecundity and longevity of Argentine ant (Hymenoptera: Formicidae) queens in response to irradiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation is a postharvest quarantine treatment option to control ants and other hitchhiker pests on fresh horticultural products traded between countries. As little is known about irradiation effects on ants, radiotolerance of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae...

  10. Break free from the product life cycle.

    PubMed

    Moon, Youngme

    2005-05-01

    Most firms build their marketing strategies around the concept of the product life cycle--the idea that after introduction, products inevitably follow a course of growth, maturity, and decline. It doesn't have to be that way, says HBS marketing professor Youngme Moon. By positioning their products in unexpected ways, companies can change how customers mentally categorize them. In doing so, they can shift products lodged in the maturity phase back--and catapult new products forward--into the growth phase. The author describes three positioning strategies that marketers use to shift consumers' thinking. Reverse positioning strips away"sacred" product attributes while adding new ones (JetBlue, for example, withheld the expected first-class seating and in-flight meals on its planes while offering surprising perks like leather seats and extra legroom). Breakaway positioning associates the product with a radically different category (Swatch chose not to associate itself with fine jewelry and instead entered the fashion accessory category). And stealth positioning acclimates leery consumers to a new offering by cloaking the product's true nature (Sony positioned its less-than-perfect household robot as a quirky pet). Clayton Christensen described how new, simple technologies can upend a market. In an analogous way, these positioning strategies can exploit the vulnerability of established categories to new positioning. A company can use these techniques to go on the offensive and transform a category by demolishing its traditional boundaries. Companies that disrupt a category through positioning create a lucrative place to ply their wares--and can leave category incumbents scrambling.

  11. Break free from the product life cycle.

    PubMed

    Moon, Youngme

    2005-05-01

    Most firms build their marketing strategies around the concept of the product life cycle--the idea that after introduction, products inevitably follow a course of growth, maturity, and decline. It doesn't have to be that way, says HBS marketing professor Youngme Moon. By positioning their products in unexpected ways, companies can change how customers mentally categorize them. In doing so, they can shift products lodged in the maturity phase back--and catapult new products forward--into the growth phase. The author describes three positioning strategies that marketers use to shift consumers' thinking. Reverse positioning strips away"sacred" product attributes while adding new ones (JetBlue, for example, withheld the expected first-class seating and in-flight meals on its planes while offering surprising perks like leather seats and extra legroom). Breakaway positioning associates the product with a radically different category (Swatch chose not to associate itself with fine jewelry and instead entered the fashion accessory category). And stealth positioning acclimates leery consumers to a new offering by cloaking the product's true nature (Sony positioned its less-than-perfect household robot as a quirky pet). Clayton Christensen described how new, simple technologies can upend a market. In an analogous way, these positioning strategies can exploit the vulnerability of established categories to new positioning. A company can use these techniques to go on the offensive and transform a category by demolishing its traditional boundaries. Companies that disrupt a category through positioning create a lucrative place to ply their wares--and can leave category incumbents scrambling. PMID:15929406

  12. [Argentine consensus on the treatment of bipolar disorders].

    PubMed

    Vázquez, Gustavo Héctor; Strejilevich, Sergio; García Bonetto, Gerardo; Cetkovich-Bakmas, Marcelo; Zaratiegui, Rodolfo; Lagomarsino, Alejandro; Goldchluk, Aníbal; Kalina, Eduardo; Herbst, Luis; Gutiérrez, Benigno

    2005-01-01

    The consensus guidelines of argentine experts in the treatment of bipolar disorders are the result of three days of work of the 10 main local experts under the organization of the Argentine Association of Biological Psychiatry (AAPB). It was adopted a mixed criterion for its preparation: all the recent data of the evidence medicine based published until now were discussed and were balanced with the knowledge acquired from clinical experience of the local experts on the bipolar field. It presents general recommendations and suggested therapeutic sequences for the phase of maintenance, the manic/hypomanic or mixed episode and the depressive episode. These have been divided according to the classification in type I and II; with or without rapid cycling. Since the group of experts identified the delay and miss-diagnoses like the most important barrier for a suitable treatment enclosed a series of recommendations for differential diagnosis of bipolar disorders.

  13. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 3 2013-04-01 2013-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative...

  14. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 3 2014-04-01 2014-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative...

  15. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 3 2012-04-01 2012-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative...

  16. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative...

  17. 19 CFR 207.27 - Short life cycle products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 3 2011-04-01 2011-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... short life cycle merchandise which has been the subject of two or more affirmative...

  18. Trap-mulching Argentine ants.

    PubMed

    Silverman, Jules; Sorenson, Clyde E; Waldvogel, Michael G

    2006-10-01

    Argentine ant, Linepithema humile (Mayr), management is constrained, in large part, by polydomy where nestmates are distributed extensively across urban landscapes, particularly within mulch. Management with trap-mulching is a novel approach derived from trap-cropping where ants are repelled from a broad domain of nest sites to smaller defined areas, which are subsequently treated with insecticide. This concept was field-tested with mulch surrounding ornamental trees replaced with a narrow band of pine (Pinus spp.) needle mulch (trap) within a much larger patch of repellent aromatic cedar (Juniperus spp.) mulch. After ants reestablished around the trees, the pine needle mulch band was treated with 0.06% fipronil (Termidor). Poor results were obtained when the trap extended from the tree trunk to the edge of the mulched area. When the trap was applied as a circular band around the tree trunk reductions in the number of foraging ants were recorded through 14 d compared with an untreated mulch control, but not for longer periods. Reductions in the number of ant nests within mulch were no different between the trap mulch and any of the other treatments. We conclude that trap-mulching offers limited benefits, and that successful management of Argentine ants will require implementation of complementary or perhaps alternative strategies.

  19. Alternate thermochemical cycles for advanced hydrogen production

    SciTech Connect

    Bowman, M.G.; Hollabaugh, C.M.; Jones, W.M.; Mason, C.F.V.

    1982-01-01

    Experimental studies have validated three classes of thermochemical cycles (Bismuth sulfate-sulfuric acid, magnesium sulfate-magnesium iodide, and oxide-based) based on high temperature solids decomposition as an endothermic step. Such cycles offer the possibility of high efficiency when coupled with high temperature isothermal heat sources. Methods for handling solids in high temperature decomposition reactions have been tested. The results suggest that efficient and practical cycles can be based on such reactions.

  20. USING LIFE CYCLE ASSESSMENT TOOLS FOR INTEGRATED PRODUCT POLICY

    EPA Science Inventory

    The European Union's new Integrated Product Policy directs governments and companies to consider the entire product life cycle, from cradle to grave, in their environmental decision-making process. A life-cycle based approach is intended to lead toward true environmental improvem...

  1. Agronomic characterization of the Argentina Indicator Region. [U.S. corn belt and Argentine pampas

    NASA Technical Reports Server (NTRS)

    Hicks, D. R. (Principal Investigator)

    1982-01-01

    An overview of the Argentina indicator region including information on topography, climate, soils and vegetation is presented followed by a regionalization of crop livestock land use. Corn/soybean production and exports as well as agricultural practices are discussed. Similarities and differences in the physical agronomic scene, crop livestock land use and agricultural practices between the U.S. corn belt and the Argentine pampa are considered. The Argentine agricultural economy is described. Crop calendars for the Argentina indicator region, an accompanying description, notes on crop-livestock zones, wheat production, field size, and agricultural problems and practices are included.

  2. Metabolic Engineering of TCA Cycle for Production of Chemicals.

    PubMed

    Vuoristo, Kiira S; Mars, Astrid E; Sanders, Johan P M; Eggink, Gerrit; Weusthuis, Ruud A

    2016-03-01

    The tricarboxylic acid (TCA) cycle has been used for decades in the microbial production of chemicals such as citrate, L-glutamate, and succinate. Maximizing yield is key for cost-competitive production. However, for most TCA cycle products, the maximum pathway yield is lower than the theoretical maximum yield (Y(E)). For succinate, this was solved by creating two pathways to the product, using both branches of the TCA cycle, connected by the glyoxylate shunt (GS). A similar solution cannot be applied directly for production of compounds from the oxidative branch of the TCA cycle because irreversible reactions are involved. Here, we describe how this can be overcome and what the impact is on the yield.

  3. Metabolic Engineering of TCA Cycle for Production of Chemicals.

    PubMed

    Vuoristo, Kiira S; Mars, Astrid E; Sanders, Johan P M; Eggink, Gerrit; Weusthuis, Ruud A

    2016-03-01

    The tricarboxylic acid (TCA) cycle has been used for decades in the microbial production of chemicals such as citrate, L-glutamate, and succinate. Maximizing yield is key for cost-competitive production. However, for most TCA cycle products, the maximum pathway yield is lower than the theoretical maximum yield (Y(E)). For succinate, this was solved by creating two pathways to the product, using both branches of the TCA cycle, connected by the glyoxylate shunt (GS). A similar solution cannot be applied directly for production of compounds from the oxidative branch of the TCA cycle because irreversible reactions are involved. Here, we describe how this can be overcome and what the impact is on the yield. PMID:26702790

  4. Organic flash cycles for efficient power production

    DOEpatents

    Ho, Tony; Mao, Samuel S.; Greif, Ralph

    2016-03-15

    This disclosure provides systems, methods, and apparatus related to an Organic Flash Cycle (OFC). In one aspect, a modified OFC system includes a pump, a heat exchanger, a flash evaporator, a high pressure turbine, a throttling valve, a mixer, a low pressure turbine, and a condenser. The heat exchanger is coupled to an outlet of the pump. The flash evaporator is coupled to an outlet of the heat exchanger. The high pressure turbine is coupled to a vapor outlet of the flash evaporator. The throttling valve is coupled to a liquid outlet of the flash evaporator. The mixer is coupled to an outlet of the throttling valve and to an outlet of the high pressure turbine. The low pressure turbine is coupled to an outlet of the mixer. The condenser is coupled to an outlet of the low pressure turbine and to an inlet of the pump.

  5. Internal cycle modeling and environmental assessment of multiple cycle consumer products

    SciTech Connect

    Tsiliyannis, C.A.

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Dynamic flow models are presented for remanufactured, reused or recycled products. Black-Right-Pointing-Pointer Early loss and stochastic return are included for fast and slow cycling products. Black-Right-Pointing-Pointer The reuse-to-input flow ratio (Internal Cycle Factor, ICF) is determined. Black-Right-Pointing-Pointer The cycle rate, which is increasing with the ICF, monitors eco-performance. Black-Right-Pointing-Pointer Early internal cycle losses diminish the ICF, the cycle rate and performance. - Abstract: Dynamic annual flow models incorporating consumer discard and usage loss and featuring deterministic and stochastic end-of-cycle (EOC) return by the consumer are developed for reused or remanufactured products (multiple cycle products, MCPs), including fast and slow cycling, short and long-lived products. It is shown that internal flows (reuse and overall consumption) increase proportionally to the dimensionless internal cycle factor (ICF) which is related to environmental impact reduction factors. The combined reuse/recycle (or cycle) rate is shown capable for shortcut, albeit effective, monitoring of environmental performance in terms of waste production, virgin material extraction and manufacturing impacts of all MCPs, a task, which physical variables (lifetime, cycling frequency, mean or total number of return trips) and conventional rates, via which environmental policy has been officially implemented (e.g. recycling rate) cannot accomplish. The cycle rate is shown to be an increasing (hyperbolic) function of ICF. The impact of the stochastic EOC return characteristics on total reuse and consumption flows, as well as on eco-performance, is assessed: symmetric EOC return has a small, positive effect on performance compared to deterministic, while early shifted EOC return is more beneficial. In order to be efficient, environmental policy should set higher minimum reuse targets for higher trippage MCPs. The

  6. Terpenoids and bibenzyls from three Argentine liverworts.

    PubMed

    Nagashima, Fumihiro; Asakawa, Yoshinori

    2011-12-16

    A new rosane diterpenoid, 3a-hydroxy-5,15-rosadien-11-one (3), was isolated, together with a known rosane diterpenoid, 5,15-rosadiene-3,11-dione (4), and an aromadendrane sesquiterpenoid, ent-cyclocolorenone (5), from the Et(2)O extract of an unidentified Argentine liverwort Anastrophyllum species. Moreover, four known sesquiterpene lactones 6-9 and two known bibenzyls 10, 11 were isolated from the Et(2)O extracts of Argentine Frullania brasiliensis and Radula voluta, respectively. The structures of compounds 3-11 were determined by the use of NMR techniques.

  7. Life Cycle Assessment Software for Product and Process Sustainability Analysis

    ERIC Educational Resources Information Center

    Vervaeke, Marina

    2012-01-01

    In recent years, life cycle assessment (LCA), a methodology for assessment of environmental impacts of products and services, has become increasingly important. This methodology is applied by decision makers in industry and policy, product developers, environmental managers, and other non-LCA specialists working on environmental issues in a wide…

  8. 76 FR 41525 - Hewlett Packard Global Parts Supply Chain, Global Product Life Cycles Management Unit Including...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-14

    ... Employment and Training Administration Hewlett Packard Global Parts Supply Chain, Global Product Life Cycles... Chain, Global Product Life Cycles Management Unit, including teleworkers reporting to Houston, Texas... Parts Supply Chain, Global Product Life Cycles Management Unit, including teleworkers reporting...

  9. Characteristics of mercury cycling in the cement production process.

    PubMed

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Wu, Qingru; Hao, Jiming

    2016-01-25

    The mercury cycling caused by dust shuttling significantly increases the atmospheric emissions from cement production. A comprehensive understanding of this mercury cycling can promote the development of mercury emission control technologies. In this study, the characteristics of mercury cycling in the cement production process were first investigated. Furthermore, the mercury enrichment and effects of dust treatment were evaluated based on the field tests conducted in two Chinese cement plants. The mercury cycling between the kiln system and the raw mill system was the most important aspect and contributed 57-73% to the total amount of mercury emitted from the kiln system. Mercury emitted from the kiln system with flue gas was enriched as high as 3.4-8.8 times in the two tested plants compared to the amount of mercury in the raw materials and coal due to mercury cycling. The mercury enrichment can be significantly affected by the proportion of mercury cycled back to the kiln system. The effects of dust treatment were evaluated, and dust treatment can efficiently reduce approximately 31-70% of atmospheric mercury emissions in the two plants. The reduction proportion approximately linearly decreased with the proportion of mercury removed from the collected dust. PMID:26448491

  10. Waste management through life cycle assessment of products

    NASA Astrophysics Data System (ADS)

    Borodin, Yu V.; Aliferova, T. E.; Ncube, A.

    2015-04-01

    The rapid growth of a population in a country can contribute to high production of waste. Municipal waste and industrial waste can bring unhealthy and unpleasant environment or even diseases to human beings if the wastes are not managed properly.With increasing concerns over waste and the need for ‘greener’ products, it is necessary to carry out Life Cycle Assessments of products and this will help manufacturers take the first steps towards greener designs by assessing their product's carbon output. Life Cycle Assessment (LCA) is a process to evaluate the environmental burdens associated with a product, process or activity by identifying and quantifying energy and materials used and wastes released to the environment, and to assess the impact of those energy and material used and released to the environment. The aim of the study was to use a life cycle assessment approach to determine which waste disposal options that will substantially reduce the environmental burdens posed by the Polyethylene Terephthalate (PET) bottle. Several important observations can be made. 1) Recycling of the PET bottle waste can significantly reduce the energy required across the life cycle because the high energy inputs needed to process the requisite virgin materials greatly exceeds the energy needs of the recycling process steps. 2) Greenhouse gases can be reduced by opting for recycling instead of landfilling and incineration. 3) Quantity of waste emissions released from different disposal options was identified. 4) Recycling is the environmentally preferable disposal method for the PET bottle. Industry can use the tools and data in this study to evaluate the health, environmental, and energy implications of the PET bottle. LCA intends to aid decision-makers in this respect, provided that the scientific underpinning is available. Strategic incentives for product development and life cycle management can then be developed.

  11. End-of-life flows of multiple cycle consumer products

    SciTech Connect

    Tsiliyannis, C.A.

    2011-11-15

    Explicit expressions for the end-of-life flows (EOL) of single and multiple cycle products (MCPs) are presented, including deterministic and stochastic EOL exit. The expressions are given in terms of the physical parameters (maximum lifetime, T, annual cycling frequency, f, number of cycles, N, and early discard or usage loss). EOL flows are also obtained for hi-tech products, which are rapidly renewed and thus may not attain steady state (e.g. electronic products, passenger cars). A ten-step recursive procedure for obtaining the dynamic EOL flow evolution is proposed. Applications of the EOL expressions and the ten-step procedure are given for electric household appliances, industrial machinery, tyres, vehicles and buildings, both for deterministic and stochastic EOL exit, (normal, Weibull and uniform exit distributions). The effect of the physical parameters and the stochastic characteristics on the EOL flow is investigated in the examples: it is shown that the EOL flow profile is determined primarily by the early discard dynamics; it also depends strongly on longevity and cycling frequency: higher lifetime or early discard/loss imply lower dynamic and steady state EOL flows. The stochastic exit shapes the overall EOL dynamic profile: Under symmetric EOL exit distribution, as the variance of the distribution increases (uniform to normal to deterministic) the initial EOL flow rise becomes steeper but the steady state or maximum EOL flow level is lower. The steepest EOL flow profile, featuring the highest steady state or maximum level, as well, corresponds to skew, earlier shifted EOL exit (e.g. Weibull). Since the EOL flow of returned products consists the sink of the reuse/remanufacturing cycle (sink to recycle) the results may be used in closed loop product lifecycle management operations for scheduling and sizing reverse manufacturing and for planning recycle logistics. Decoupling and quantification of both the full age EOL and of the early discard flows is

  12. SAC-B, Argentine scientific satellite

    NASA Technical Reports Server (NTRS)

    Gulich, J. M.; White, C.

    1994-01-01

    The project and the missions of the Argentine scientific satellite, SAC-B, are summarized. SAC-B is an international cooperative project between NASA and the Secretariat of State of Science and Technology of the Argentine Republic. The objective of SAC-B is to advance the study of solar physics and astrophysics through the examination of solar flares, gamma ray burst sources and the diffuse soft X-ray cosmic background. The scientific payload comprises an instrument to measure the temporal evolution of X-ray emissions from solar flares as well as nonsolar gamma ray bursts, a combined soft X-ray and gamma ray burst detector, a diffuse X-ray background detector, and an energetic neutral atoms detector.

  13. Argentine hemorrhagic fever: a primate model.

    PubMed

    Weissenbacher, M C; Calello, M A; Colillas, O J; Rondinone, S N; Frigerio, M J

    1979-01-01

    Experimental Junin virus infection of a New World primate, Callithrix jacchus, was evaluated. The virus produced anorexia, loss of weight, thrombocytopenia, leukopenia, and hemorrhagic and neurological symptoms and terminated in death. Virus was recovered from urine, blood samples and all tissues taken at autopsy. These preliminary observations show that several aspects of the experimental disease in C. jacchus are quite similar to severe natural Argentine hemorrhagic fever of man.

  14. Beef production in balance: considerations for life cycle analyses.

    PubMed

    Place, Sara E; Mitloehner, Frank M

    2012-11-01

    Life Cycle Assessments (LCA) are useful tools to analyze a product's "carbon footprint" (e.g., the net greenhouse gas (GHG) emissions expressed as standardized carbon dioxide equivalents per unit of product) considering all phases of the production chain. For beef, an LCA would include the GHG emissions from feed production, from the enteric fermentation of the cattle, from the cattle's waste, and from processing and transportation. Identifying the scope and scale of the LCA is critical and key to preventing inappropriate applications of the analysis (e.g., applying a global LCA for beef to the regional or national scale). Ideally, a LCA can integrate the complex biogeochemical processes responsible for GHG emissions and the disparate animal and agricultural management techniques used be different phases of the beef production chain (e.g., feedlot vs. cow-calf) and different production systems (e.g., conventional vs. organic). PMID:22551868

  15. Performance improvement: an active life cycle product management

    NASA Astrophysics Data System (ADS)

    Cucchiella, Federica; Gastaldi, Massimo; Lenny Koh, S. C.

    2010-03-01

    The management of the supply chain has gained importance in many manufacturing firms. Operational flexibility can be considered a crucial weapon to increase competitiveness in a turbulent marketplace. It reflects the ability of a firm to properly and rapidly respond to a variable and dynamic environment. For the firm operating in a fashion sector, the management of the supply chain is even more complex because the product life cycle is shorter than that of the firm operating in a non-fashion sector. The increase of firm flexibility level can be reached through the application of the real option theory inside the firm network. In fact, real option may increase the project value by allowing managers to more efficiently direct the production. The real option application usually analysed in literature does not take into account that the demands of products are well-defined by the product life cycle. Working on a fashion sector, the life cycle pattern is even more relevant because of an expected demand that grows according to a constant rate that does not capture the demand dynamics of the underlying fashion goods. Thus, the primary research objective of this article is to develop a model useful for the management of investments in a supply chain operating in a fashion sector where the system complexity is increased by the low level of unpredictability and stability that is proper of the mood phenomenon. Moreover, unlike the traditional model, a real option framework is presented here that considers fashion product characterised by uncertain stages of the production cycle.

  16. Powerful motors: Kinship, citizenship and the transformation of the Argentine oil industry

    NASA Astrophysics Data System (ADS)

    Shever, Elana

    The privatization of the Argentine oil industry has been described as an unprecedented transfer of property, capital and control from the state to the corporate sphere, but this study demonstrates that the privatization process is better understood as a transformation of the historical configurations of oil-fueled development, political communities and human subjectivities. This dissertation probes the development of the state-led oil industry, and the shift to a corporate-led one, through an ethnography of Argentines differently positioned in relation to the global oil industry. The ethnography explores the lives of middle class oil workers and their families in Northwest Patagonia, impoverished residents of the shanty neighborhoods near the refineries in metropolitan Buenos Aires, and affluent employees of the translocal corporations operating in the Argentine oil fields. After the Introduction delineates this study's four principal interventions into anthropological scholarship, each subsequent chapter engages a particular problem that cuts across the Argentine oil fields and the anthropological theoretical fields. Chapter Two scrutinizes the historical construction of the Argentine subterritory as a "natural" space of value. Chapters Three and Four investigate the articulation of capitalist production and filial reproduction. These chapters argue that sentiment is a crucial generative force that has shaped the oil industry, company towns and worker families from the founding of the state-owned oil company in beginning of the twentieth century to its conversion into a corporate-owned one at the century's close. Chapters Five and Six examine the emergence of consumer citizenship and corporate citizenship out of Argentine neoliberalismo and its transformation of the oil industry. They argue that consumer and corporate citizenship are both reformulations of the older traditions of liberalism and Peronism. All the chapters of this dissertation illustrate that the

  17. Microalgal biomass production pathways: evaluation of life cycle environmental impacts

    PubMed Central

    2013-01-01

    Background Microalgae are touted as an attractive alternative to traditional forms of biomass for biofuel production, due to high productivity, ability to be cultivated on marginal lands, and potential to utilize carbon dioxide (CO2) from industrial flue gas. This work examines the fossil energy return on investment (EROIfossil), greenhouse gas (GHG) emissions, and direct Water Demands (WD) of producing dried algal biomass through the cultivation of microalgae in Open Raceway Ponds (ORP) for 21 geographic locations in the contiguous United States (U.S.). For each location, comprehensive life cycle assessment (LCA) is performed for multiple microalgal biomass production pathways, consisting of a combination of cultivation and harvesting options. Results Results indicate that the EROIfossil for microalgae biomass vary from 0.38 to 1.08 with life cycle GHG emissions of −46.2 to 48.9 (g CO2 eq/MJ-biomass) and direct WDs of 20.8 to 38.8 (Liters/MJ-biomass) over the range of scenarios analyzed. Further anaylsis reveals that the EROIfossil for production pathways is relatively location invariant, and that algae’s life cycle energy balance and GHG impacts are highly dependent on cultivation and harvesting parameters. Contrarily, algae’s direct water demands were found to be highly sensitive to geographic location, and thus may be a constraining factor in sustainable algal-derived biofuel production. Additionally, scenarios with promising EROIfossil and GHG emissions profiles are plagued with high technological uncertainty. Conclusions Given the high variability in microalgae’s energy and environmental performance, careful evaluation of the algae-to-fuel supply chain is necessary to ensure the long-term sustainability of emerging algal biofuel systems. Alternative production scenarios and technologies may have the potential to reduce the critical demands of biomass production, and should be considered to make algae a viable and more efficient biofuel alternative

  18. Life Cycle Assessment for the Production of Oil Palm Seeds

    PubMed Central

    Muhamad, Halimah; Ai, Tan Yew; Khairuddin, Nik Sasha Khatrina; Amiruddin, Mohd Din; May, Choo Yuen

    2014-01-01

    The oil palm seed production unit that generates germinated oil palm seeds is the first link in the palm oil supply chain, followed by the nursery to produce seedling, the plantation to produce fresh fruit bunches (FFB), the mill to produce crude palm oil (CPO) and palm kernel, the kernel crushers to produce crude palm kernel oil (CPKO), the refinery to produce refined palm oil (RPO) and finally the palm biodiesel plant to produce palm biodiesel. This assessment aims to investigate the life cycle assessment (LCA) of germinated oil palm seeds and the use of LCA to identify the stage/s in the production of germinated oil palm seeds that could contribute to the environmental load. The method for the life cycle impact assessment (LCIA) is modelled using SimaPro version 7, (System for Integrated environMental Assessment of PROducts), an internationally established tool used by LCA practitioners. This software contains European and US databases on a number of materials in addition to a variety of European- and US-developed impact assessment methodologies. LCA was successfully conducted for five seed production units and it was found that the environmental impact for the production of germinated oil palm was not significant. The characterised results of the LCIA for the production of 1000 germinated oil palm seeds showed that fossil fuel was the major impact category followed by respiratory inorganics and climate change. PMID:27073598

  19. Life Cycle Assessment for the Production of Oil Palm Seeds.

    PubMed

    Muhamad, Halimah; Ai, Tan Yew; Khairuddin, Nik Sasha Khatrina; Amiruddin, Mohd Din; May, Choo Yuen

    2014-12-01

    The oil palm seed production unit that generates germinated oil palm seeds is the first link in the palm oil supply chain, followed by the nursery to produce seedling, the plantation to produce fresh fruit bunches (FFB), the mill to produce crude palm oil (CPO) and palm kernel, the kernel crushers to produce crude palm kernel oil (CPKO), the refinery to produce refined palm oil (RPO) and finally the palm biodiesel plant to produce palm biodiesel. This assessment aims to investigate the life cycle assessment (LCA) of germinated oil palm seeds and the use of LCA to identify the stage/s in the production of germinated oil palm seeds that could contribute to the environmental load. The method for the life cycle impact assessment (LCIA) is modelled using SimaPro version 7, (System for Integrated environMental Assessment of PROducts), an internationally established tool used by LCA practitioners. This software contains European and US databases on a number of materials in addition to a variety of European- and US-developed impact assessment methodologies. LCA was successfully conducted for five seed production units and it was found that the environmental impact for the production of germinated oil palm was not significant. The characterised results of the LCIA for the production of 1000 germinated oil palm seeds showed that fossil fuel was the major impact category followed by respiratory inorganics and climate change.

  20. Life Cycle Assessment for the Production of Oil Palm Seeds.

    PubMed

    Muhamad, Halimah; Ai, Tan Yew; Khairuddin, Nik Sasha Khatrina; Amiruddin, Mohd Din; May, Choo Yuen

    2014-12-01

    The oil palm seed production unit that generates germinated oil palm seeds is the first link in the palm oil supply chain, followed by the nursery to produce seedling, the plantation to produce fresh fruit bunches (FFB), the mill to produce crude palm oil (CPO) and palm kernel, the kernel crushers to produce crude palm kernel oil (CPKO), the refinery to produce refined palm oil (RPO) and finally the palm biodiesel plant to produce palm biodiesel. This assessment aims to investigate the life cycle assessment (LCA) of germinated oil palm seeds and the use of LCA to identify the stage/s in the production of germinated oil palm seeds that could contribute to the environmental load. The method for the life cycle impact assessment (LCIA) is modelled using SimaPro version 7, (System for Integrated environMental Assessment of PROducts), an internationally established tool used by LCA practitioners. This software contains European and US databases on a number of materials in addition to a variety of European- and US-developed impact assessment methodologies. LCA was successfully conducted for five seed production units and it was found that the environmental impact for the production of germinated oil palm was not significant. The characterised results of the LCIA for the production of 1000 germinated oil palm seeds showed that fossil fuel was the major impact category followed by respiratory inorganics and climate change. PMID:27073598

  1. Integrated design strategy for product life-cycle management

    NASA Astrophysics Data System (ADS)

    Johnson, G. Patrick

    2001-02-01

    Two major trends suggest new considerations for environmentally conscious manufacturing (ECM) -- the continuation of dematerialization and the growing trend toward goods becoming services. A diversity of existing research could be integrated around those trends in ways that can enhance ECM. Major research-based achievements in information, computation, and communications systems, sophisticated and inexpensive sensing capabilities, highly automated and precise manufacturing technologies, and new materials continue to drive the phenomenon of dematerialization - the reduction of the material and energy content of per capita GDP. Knowledge is also growing about the sociology, economics, mathematics, management and organization of complex socio-economic systems. And that has driven a trend towards goods evolving into services. But even with these significant trends, the value of material, energy, information and human resources incorporated into the manufacture, use and disposal of modern products and services often far exceeds the benefits realized. Multi-disciplinary research integrating these drivers with advances in ECM concepts could be the basis for a new strategy of production. It is argued that a strategy of integrating information resources with physical and human resources over product life cycles, together with considering products as streams of service over time, could lead to significant economic payoff. That strategy leads to an overall design concept to minimize costs of all resources over the product life cycle to more fully capture benefits of all resources incorporated into modern products. It is possible by including life cycle monitoring, periodic component replacement, re-manufacture, salvage and human factor skill enhancement into initial design.

  2. Mitochondrial engineering of the TCA cycle for fumarate production.

    PubMed

    Chen, Xiulai; Dong, Xiaoxiang; Wang, Yuancai; Zhao, Zihao; Liu, Liming

    2015-09-01

    Microbial fumarate production from renewable feedstock is a promising and sustainable alternative to petroleum-based chemical synthesis. Here, mitochondrial engineering was used to construct the oxidative pathway for fumarate production starting from the TCA cycle intermediate α-ketoglutarate in Candida glabrata. Accordingly, α-ketoglutarate dehydrogenase complex (KGD), succinyl-CoA synthetase (SUCLG), and succinate dehydrogenase (SDH) were selected to be manipulated for strengthening the oxidative pathway, and the engineered strain T.G-K-S-S exhibited increased fumarate biosynthesis (1.81 g L(-1)). To further improve fumarate production, the oxidative route was optimized. First, three fusion proteins KGD2-SUCLG2, SUCLG2-SDH1 and KGD2-SDH1 were constructed, and KGD2-SUCLG2 led to improved fumarate production (4.24 g L(-1)). In addition, various strengths of KGD2-SUCLG2 and SDH1 expression cassettes were designed by combinations of promoter strengths and copy numbers, resulting in a large increase in fumarate production (from 4.24 g L(-1) to 8.24 g L(-1)). Then, through determining intracellular amino acids and its related gene expression levels, argininosuccinate lyase in the urea cycle was identified as the key factor for restricting higher fumarate production. Correspondingly, after overexpression of it, the fumarate production was further increased to 9.96 g L(-1). Next, two dicarboxylic acids transporters facilitated an improvement of fumarate production, and, as a result, the final strain T.G-KS(H)-S(M)-A-2S reached fumarate titer of 15.76 g L(-1). This strategy described here paves the way to the development of an efficient pathway for microbial production of fumarate.

  3. Mitochondrial engineering of the TCA cycle for fumarate production.

    PubMed

    Chen, Xiulai; Dong, Xiaoxiang; Wang, Yuancai; Zhao, Zihao; Liu, Liming

    2015-09-01

    Microbial fumarate production from renewable feedstock is a promising and sustainable alternative to petroleum-based chemical synthesis. Here, mitochondrial engineering was used to construct the oxidative pathway for fumarate production starting from the TCA cycle intermediate α-ketoglutarate in Candida glabrata. Accordingly, α-ketoglutarate dehydrogenase complex (KGD), succinyl-CoA synthetase (SUCLG), and succinate dehydrogenase (SDH) were selected to be manipulated for strengthening the oxidative pathway, and the engineered strain T.G-K-S-S exhibited increased fumarate biosynthesis (1.81 g L(-1)). To further improve fumarate production, the oxidative route was optimized. First, three fusion proteins KGD2-SUCLG2, SUCLG2-SDH1 and KGD2-SDH1 were constructed, and KGD2-SUCLG2 led to improved fumarate production (4.24 g L(-1)). In addition, various strengths of KGD2-SUCLG2 and SDH1 expression cassettes were designed by combinations of promoter strengths and copy numbers, resulting in a large increase in fumarate production (from 4.24 g L(-1) to 8.24 g L(-1)). Then, through determining intracellular amino acids and its related gene expression levels, argininosuccinate lyase in the urea cycle was identified as the key factor for restricting higher fumarate production. Correspondingly, after overexpression of it, the fumarate production was further increased to 9.96 g L(-1). Next, two dicarboxylic acids transporters facilitated an improvement of fumarate production, and, as a result, the final strain T.G-KS(H)-S(M)-A-2S reached fumarate titer of 15.76 g L(-1). This strategy described here paves the way to the development of an efficient pathway for microbial production of fumarate. PMID:25708514

  4. Advanced Electrochemical Technologies for Hydrogen Production by Alternative Thermochemical Cycles

    SciTech Connect

    Lvov, Serguei; Chung, Mike; Fedkin, Mark; Lewis, Michele; Balashov, Victor; Chalkova, Elena; Akinfiev, Nikolay; Stork, Carol; Davis, Thomas; Gadala-Maria, Francis; Stanford, Thomas; Weidner, John; Law, Victor; Prindle, John

    2011-01-06

    Hydrogen fuel is a potentially major solution to the problem of climate change, as well as addressing urban air pollution issues. But a key future challenge for hydrogen as a clean energy carrier is a sustainable, low-cost method of producing it in large capacities. Most of the world's hydrogen is currently derived from fossil fuels through some type of reforming processes. Nuclear hydrogen production is an emerging and promising alternative to the reforming processes for carbon-free hydrogen production in the future. This report presents the main results of a research program carried out by a NERI Consortium, which consisted of Penn State University (PSU) (lead), University of South Carolina (USC), Tulane University (TU), and Argonne National Laboratory (ANL). Thermochemical water decomposition is an emerging technology for large-scale production of hydrogen. Typically using two or more intermediate compounds, a sequence of chemical and physical processes split water into hydrogen and oxygen, without releasing any pollutants externally to the atmosphere. These intermediate compounds are recycled internally within a closed loop. While previous studies have identified over 200 possible thermochemical cycles, only a few have progressed beyond theoretical calculations to working experimental demonstrations that establish scientific and practical feasibility of the thermochemical processes. The Cu-Cl cycle has a significant advantage over other cycles due to lower temperature requirements – around 530 °C and below. As a result, it can be eventually linked with the Generation IV thermal power stations. Advantages of the Cu-Cl cycle over others include lower operating temperatures, ability to utilize low-grade waste heat to improve energy efficiency, and potentially lower cost materials. Another significant advantage is a relatively low voltage required for the electrochemical step (thus low electricity input). Other advantages include common chemical agents and

  5. Hybrid life-cycle assessment of algal biofuel production.

    PubMed

    Malik, Arunima; Lenzen, Manfred; Ralph, Peter J; Tamburic, Bojan

    2015-05-01

    The objective of this work is to establish whether algal bio-crude production is environmentally, economically and socially sustainable. To this end, an economic multi-regional input-output model of Australia was complemented with engineering process data on algal bio-crude production. This model was used to undertake hybrid life-cycle assessment for measuring the direct, as well as indirect impacts of producing bio-crude. Overall, the supply chain of bio-crude is more sustainable than that of conventional crude oil. The results indicate that producing 1 million tonnes of bio-crude will generate almost 13,000 new jobs and 4 billion dollars' worth of economic stimulus. Furthermore, bio-crude production will offer carbon sequestration opportunities as the production process is net carbon-negative.

  6. Hybrid life-cycle assessment of algal biofuel production.

    PubMed

    Malik, Arunima; Lenzen, Manfred; Ralph, Peter J; Tamburic, Bojan

    2015-05-01

    The objective of this work is to establish whether algal bio-crude production is environmentally, economically and socially sustainable. To this end, an economic multi-regional input-output model of Australia was complemented with engineering process data on algal bio-crude production. This model was used to undertake hybrid life-cycle assessment for measuring the direct, as well as indirect impacts of producing bio-crude. Overall, the supply chain of bio-crude is more sustainable than that of conventional crude oil. The results indicate that producing 1 million tonnes of bio-crude will generate almost 13,000 new jobs and 4 billion dollars' worth of economic stimulus. Furthermore, bio-crude production will offer carbon sequestration opportunities as the production process is net carbon-negative. PMID:25465782

  7. Fuel-cycle assessment of selected bioethanol production.

    SciTech Connect

    Wu, M.; Wang, M.; Hong, H.; Energy Systems

    2007-01-31

    A large amount of corn stover is available in the U.S. corn belt for the potential production of cellulosic bioethanol when the production technology becomes commercially ready. In fact, because corn stover is already available, it could serve as a starting point for producing cellulosic ethanol as a transportation fuel to help reduce the nation's demand for petroleum oil. Using the data available on the collection and transportation of corn stover and on the production of cellulosic ethanol, we have added the corn stover-to-ethanol pathway in the GREET model, a fuel-cycle model developed at Argonne National Laboratory. We then analyzed the life-cycle energy use and emission impacts of corn stover-derived fuel ethanol for use as E85 in flexible fuel vehicles (FFVs). The analysis included fertilizer manufacturing, corn farming, farming machinery manufacturing, stover collection and transportation, ethanol production, ethanol transportation, and ethanol use in light-duty vehicles (LDVs). Energy consumption of petroleum oil and fossil energy, emissions of greenhouse gases (carbon dioxide [CO{sub 2}], nitrous oxide [N{sub 2}O], and methane [CH{sub 4}]), and emissions of criteria pollutants (carbon monoxide [CO], volatile organic compounds [VOCs], nitrogen oxide [NO{sub x}], sulfur oxide [SO{sub x}], and particulate matter with diameters smaller than 10 micrometers [PM{sub 10}]) during the fuel cycle were estimated. Scenarios of ethanol from corn grain, corn stover, and other cellulosic feedstocks were then compared with petroleum reformulated gasoline (RFG). Results showed that FFVs fueled with corn stover ethanol blends offer substantial energy savings (94-95%) relative to those fueled with RFG. For each Btu of corn stover ethanol produced and used, 0.09 Btu of fossil fuel is required. The cellulosic ethanol pathway avoids 86-89% of greenhouse gas emissions. Unlike the life cycle of corn grain-based ethanol, in which the ethanol plant consumes most of the fossil fuel

  8. Life cycle assessment of biodiesel production in China.

    PubMed

    Liang, Sai; Xu, Ming; Zhang, Tianzhu

    2013-02-01

    This study aims to evaluate energy, economic, and environmental performances of seven categories of biodiesel feedstocks by using the mixed-unit input-output life cycle assessment method. Various feedstocks have different environmental performances, indicating potential environmental problem-shift. Jatropha seed, castor seed, waste cooking oil, and waste extraction oil are preferred feedstocks for biodiesel production in the short term. Positive net energy yields and positive net economic benefits of biodiesel from these four feedstocks are 2.3-52.0% of their life cycle energy demands and 74.1-448.4% of their economic costs, respectively. Algae are preferred in the long term mainly due to their less arable land demands. Special attention should be paid to potential environmental problems accompanying feedstock choice: freshwater use, ecotoxicity potentials, photochemical oxidation potential, acidification potential and eutrophication potential. Moreover, key processes are identified by sensitivity analysis to direct future technology improvements. Finally, supporting measures are proposed to optimize China's biodiesel development.

  9. An evaluation of life cycle assessment of European milk production.

    PubMed

    Yan, Ming-Jia; Humphreys, James; Holden, Nicholas M

    2011-03-01

    Life cycle assessment (LCA) is a method regulated by ISO that conveys the environmental impact of products. LCA studies of the same product should be comparable to benefit environmental policy making. LCA of milk production has evaluated environmental issues such as greenhouse gas emissions, resource utilisation and land use change. Thirteen LCA studies of European milk production were analysed for comparability, and direct comparison was difficult due to technical issues, arbitrary choices and inconsistent assumptions. The strengths and weaknesses of LCA for evaluating an agricultural system are identified and improvements for comparability of future studies are also considered. Future LCA of milk production should ensure that: (1) the production system is appropriately characterized according to the goal of study; (2) a clear description of the system boundary and allocation procedures is provided according to ISO standards; (3) a common functional unit, probably Energy Corrected Milk, should be used or assumed fat and protein content presented to enable comparisons; (4) where appropriate, site-specific emission factors and characterization factors should be used in environmental hotspots (e.g. manure management, spreading of synthetic fertilizer, production of purchased feed), and phosphorous loss should be better addressed; (5) a range of impact categories including climate change, energy use, land use, acidification and eutrophication should be used to assess pollution swapping, all of which are subject to national or regional directives; perhaps in the future biodiversity should also be included; and (6) the sensitivity to choices of methods and uncertainty of final results should be evaluated. PMID:21055870

  10. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese.

    PubMed

    Martino, Gabriela P; Quintana, Ingrid M; Espariz, Martín; Blancato, Victor S; Gallina Nizo, Gabriel; Esteban, Luis; Magni, Christian

    2016-02-04

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production.

  11. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese

    PubMed Central

    Martino, Gabriela P.; Quintana, Ingrid M.; Espariz, Martín; Blancato, Victor S.; Gallina Nizo, Gabriel; Esteban, Luis

    2016-01-01

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production. PMID:26847907

  12. Entropy production and fluctuation theorem along a stochastic limit cycle.

    PubMed

    Xiao, Tie Jun; Hou, Zhonghuai; Xin, Houwen

    2008-09-21

    Entropy production along a trajectory in the stochastic irreversible Brusselator model of chemical oscillating reactions is discussed. Particular attention is paid to a parameter region near the deterministic supercritical Hopf bifurcation. In the stationary state, detailed fluctuation theorem holds due to the reversibility in the state space, which is verified by direct simulations via Gillespie's algorithm [J. Comput. Phys. 22, 403 (1976); J. Phys. Chem. 81, 2340 (1977)]. In addition, we have considered how the entropy production along a noisy limit cycle depends on the system size. Interestingly, in the large system size limit, the entropy production approaches a constant value when the control parameter stays at the deterministic steady state region, while it increases linearly in the deterministic oscillatory region. Such simulation results can be well understood by a stochastic normal form analysis. PMID:19044968

  13. Entropy production and fluctuation theorem along a stochastic limit cycle

    NASA Astrophysics Data System (ADS)

    Xiao, Tie Jun; Hou, Zhonghuai; Xin, Houwen

    2008-09-01

    Entropy production along a trajectory in the stochastic irreversible Brusselator model of chemical oscillating reactions is discussed. Particular attention is paid to a parameter region near the deterministic supercritical Hopf bifurcation. In the stationary state, detailed fluctuation theorem holds due to the reversibility in the state space, which is verified by direct simulations via Gillespie's algorithm [J. Comput. Phys. 22, 403 (1976); J. Phys. Chem. 81, 2340 (1977)]. In addition, we have considered how the entropy production along a noisy limit cycle depends on the system size. Interestingly, in the large system size limit, the entropy production approaches a constant value when the control parameter stays at the deterministic steady state region, while it increases linearly in the deterministic oscillatory region. Such simulation results can be well understood by a stochastic normal form analysis.

  14. Life-Cycle Assessment of Pyrolysis Bio-Oil Production*

    SciTech Connect

    Steele, Philip; Puettmann, Maureen E.; Penmetsa, Venkata Kanthi; Cooper, Jerome E.

    2012-07-01

    As part ofthe Consortium for Research on Renewable Industrial Materials' Phase I life-cycle assessments ofbiofuels, lifecycle inventory burdens from the production of bio-oil were developed and compared with measures for residual fuel oil. Bio-oil feedstock was produced using whole southern pine (Pinus taeda) trees, chipped, and converted into bio-oil by fast pyrolysis. Input parameters and mass and energy balances were derived with Aspen. Mass and energy balances were input to SimaPro to determine the environmental performance of bio-oil compared with residual fuel oil as a heating fuel. Equivalent functional units of 1 MJ were used for demonstrating environmental preference in impact categories, such as fossil fuel use and global warming potential. Results showed near carbon neutrality of the bio-oil. Substituting bio-oil for residual fuel oil, based on the relative carbon emissions of the two fuels, estimated a reduction in CO2 emissions by 0.075 kg CO2 per MJ of fuel combustion or a 70 percent reduction in emission over residual fuel oil. The bio-oil production life-cycle stage consumed 92 percent of the total cradle-to-grave energy requirements, while feedstock collection, preparation, and transportation consumed 4 percent each. This model provides a framework to better understand the major factors affecting greenhouse gas emissions related to bio-oil production and conversion to boiler fuel during fast pyrolysis.

  15. Support for life-cycle product reuse in NASA's SSE

    NASA Technical Reports Server (NTRS)

    Shotton, Charles

    1989-01-01

    The Software Support Environment (SSE) is a software factory for the production of Space Station Freedom Program operational software. The SSE is to be centrally developed and maintained and used to configure software production facilities in the field. The PRC product TTCQF provides for an automated qualification process and analysis of existing code that can be used for software reuse. The interrogation subsystem permits user queries of the reusable data and components which have been identified by an analyzer and qualified with associated metrics. The concept includes reuse of non-code life-cycle components such as requirements and designs. Possible types of reusable life-cycle components include templates, generics, and as-is items. Qualification of reusable elements requires analysis (separation of candidate components into primitives), qualification (evaluation of primitives for reusability according to reusability criteria) and loading (placing qualified elements into appropriate libraries). There can be different qualifications for different installations, methodologies, applications and components. Identifying reusable software and related components is labor-intensive and is best carried out as an integrated function of an SSE.

  16. Identifying improvement potentials in cement production with life cycle assessment.

    PubMed

    Boesch, Michael Elias; Hellweg, Stefanie

    2010-12-01

    Cement production is an environmentally relevant process responsible for 5% of total anthropogenic carbon dioxide emissions and 7% of industrial fuel use. In this study, life cycle assessment is used to evaluate improvement potentials in the cement production process in Europe and the USA. With a current fuel substitution rate of 18% in Europe and 11% in the USA, both regions have a substantial potential to reduce greenhouse gas emissions and save virgin resources by further increasing the coprocessing of waste fuels. Upgrading production technology would be particularly effective in the USA where many kiln systems with very low energy efficiency are still in operation. Using best available technology and a thermal substitution rate of 50% for fuels, greenhouse gas emissions could be reduced by 9% for Europe and 18% for the USA per tonne of cement. Since clinker production is the dominant pollution producing step in cement production, the substitution of clinker with mineral components such as ground granulated blast furnace slag or fly ash is an efficient measure to reduce the environmental impact. Blended cements exhibit substantially lower environmental footprints than Portland cement, even if the substitutes feature lower grindability and require additional drying and large transport distances. The highest savings in CO(2) emissions and resource consumption are achieved with a combination of measures in clinker production and cement blending. PMID:21047057

  17. Identifying improvement potentials in cement production with life cycle assessment.

    PubMed

    Boesch, Michael Elias; Hellweg, Stefanie

    2010-12-01

    Cement production is an environmentally relevant process responsible for 5% of total anthropogenic carbon dioxide emissions and 7% of industrial fuel use. In this study, life cycle assessment is used to evaluate improvement potentials in the cement production process in Europe and the USA. With a current fuel substitution rate of 18% in Europe and 11% in the USA, both regions have a substantial potential to reduce greenhouse gas emissions and save virgin resources by further increasing the coprocessing of waste fuels. Upgrading production technology would be particularly effective in the USA where many kiln systems with very low energy efficiency are still in operation. Using best available technology and a thermal substitution rate of 50% for fuels, greenhouse gas emissions could be reduced by 9% for Europe and 18% for the USA per tonne of cement. Since clinker production is the dominant pollution producing step in cement production, the substitution of clinker with mineral components such as ground granulated blast furnace slag or fly ash is an efficient measure to reduce the environmental impact. Blended cements exhibit substantially lower environmental footprints than Portland cement, even if the substitutes feature lower grindability and require additional drying and large transport distances. The highest savings in CO(2) emissions and resource consumption are achieved with a combination of measures in clinker production and cement blending.

  18. Cycle Configurations for a PBMR Steam and Electricity Production Plant

    SciTech Connect

    Matzner, Dieter; Kriel, Willem; Correia, Michael; Greyvenstein, Renee

    2006-07-01

    The Pebble Bed Modular Reactor (PBMR) is an advanced helium-cooled, graphite moderated High Temperature Gas-cooled Reactor (HTGR) that is capable of multiple missions. The petrochemical industry requires the use of high temperature steam and electricity for their processes. Currently coal or natural gas is utilised for the generation of high temperature steam and electricity, which under-utilises natural resources and in the process emits CO{sub 2} into the atmosphere. This paper provides an overview of the PBMR product development path and discusses how steam production forms part of the future possibilities of the PBMR technology. Suitable cycle configurations for both process steam and electricity generation as required by petrochemical plants are discussed. (authors)

  19. Microbial nitrogen cycling response to forest-based bioenergy production.

    PubMed

    Minick, Kevan J; Strahm, Brian D; Fox, Thomas R; Sucre, Eric B; Leggett, Zakiya H

    2015-12-01

    Concern over rising atmospheric CO2 and other greenhouse gases due to fossil fuel combustion has intensified research into carbon-neutral energy production. Approximately 15.8 million ha of pine plantations exist across the southeastern United States, representing a vast land area advantageous for bioenergy production without significant landuse change or diversion of agricultural resources from food production. Furthermore, intercropping of pine with bioenergy grasses could provide annually harvestable, lignocellulosic biomass feedstocks along with production of traditional wood products. Viability of such a system hinges in part on soil nitrogen (N) availability and effects of N competition between pines and grasses on ecosystem productivity. We investigated effects of intercropping loblolly pine (Pinus taeda) with switchgrass (Panicum virgatum) on microbial N cycling processes in the Lower Coastal Plain of North Carolina, USA. Soil samples were collected from bedded rows of pine and interbed space of two treatments, composed of either volunteer native woody and herbaceous vegetation (pine-native) or pure switchgrass (pine-switchgrass) in interbeds. An in vitro 15N pool-dilution technique was employed to quantify gross N transformations at two soil depths (0-5 and 5-15 cm) on four dates in 2012-2013. At the 0-5 cm depth in beds of the pine-switchgrass treatment, gross N mineralization was two to three times higher in November and February compared to the pine-native treatment, resulting in increased NH4(+) availability. Gross and net nitrification were also significantly higher in February in the same pine beds. In interbeds of the pine-switchgrass treatment, gross N mineralization was lower from April to November, but higher in February, potentially reflecting positive effects of switchgrass root-derived C inputs during dormancy on microbial activity. These findings indicate soil N cycling and availability has increased in pine beds of the pine

  20. Microbial nitrogen cycling response to forest-based bioenergy production.

    PubMed

    Minick, Kevan J; Strahm, Brian D; Fox, Thomas R; Sucre, Eric B; Leggett, Zakiya H

    2015-12-01

    Concern over rising atmospheric CO2 and other greenhouse gases due to fossil fuel combustion has intensified research into carbon-neutral energy production. Approximately 15.8 million ha of pine plantations exist across the southeastern United States, representing a vast land area advantageous for bioenergy production without significant landuse change or diversion of agricultural resources from food production. Furthermore, intercropping of pine with bioenergy grasses could provide annually harvestable, lignocellulosic biomass feedstocks along with production of traditional wood products. Viability of such a system hinges in part on soil nitrogen (N) availability and effects of N competition between pines and grasses on ecosystem productivity. We investigated effects of intercropping loblolly pine (Pinus taeda) with switchgrass (Panicum virgatum) on microbial N cycling processes in the Lower Coastal Plain of North Carolina, USA. Soil samples were collected from bedded rows of pine and interbed space of two treatments, composed of either volunteer native woody and herbaceous vegetation (pine-native) or pure switchgrass (pine-switchgrass) in interbeds. An in vitro 15N pool-dilution technique was employed to quantify gross N transformations at two soil depths (0-5 and 5-15 cm) on four dates in 2012-2013. At the 0-5 cm depth in beds of the pine-switchgrass treatment, gross N mineralization was two to three times higher in November and February compared to the pine-native treatment, resulting in increased NH4(+) availability. Gross and net nitrification were also significantly higher in February in the same pine beds. In interbeds of the pine-switchgrass treatment, gross N mineralization was lower from April to November, but higher in February, potentially reflecting positive effects of switchgrass root-derived C inputs during dormancy on microbial activity. These findings indicate soil N cycling and availability has increased in pine beds of the pine

  1. Enforced ATP futile cycling increases specific productivity and yield of anaerobic lactate production in Escherichia coli.

    PubMed

    Hädicke, Oliver; Bettenbrock, Katja; Klamt, Steffen

    2015-10-01

    The manipulation of cofactor pools such as ATP or NAD(P)H has for long been recognized as key targets for metabolic engineering of microorganisms to improve yields and productivities of biotechnological processes. Several works in the past have shown that enforcing ATP futile cycling may enhance the synthesis of certain products under aerobic conditions. However, case studies demonstrating that ATP wasting may also have beneficial effects for anaerobic production processes are scarce. Taking lactic acid as an economically relevant product, we demonstrate that induction of ATP futile cycling in Escherichia coli leads to increased yields and specific production rates under anaerobic conditions, even in the case where lactate is already produced with high yields. Specifically, we constructed a high lactate producer strain KBM10111 (= MG1655 ΔadhE::Cam ΔackA-pta) and implemented an IPTG-inducible overexpression of ppsA encoding for PEP synthase which, together with pyruvate kinase, gives rise to an ATP consuming cycle. Under induction of ppsA, KBM10111 exhibits a 25% higher specific lactate productivity as well as an 8% higher lactate yield. Furthermore, the specific substrate uptake rate was increased by 14%. However, trade-offs between specific and volumetric productivities must be considered when ATP wasting strategies are used to shift substrate conversion from biomass to product synthesis and we discuss potential solutions to design optimal processes. In summary, enforced ATP futile cycling has great potential to optimize a variety of production processes and our study demonstrates that this holds true also for anaerobic processes.

  2. Enriching step-based product information models to support product life-cycle activities

    NASA Astrophysics Data System (ADS)

    Sarigecili, Mehmet Ilteris

    The representation and management of product information in its life-cycle requires standardized data exchange protocols. Standard for Exchange of Product Model Data (STEP) is such a standard that has been used widely by the industries. Even though STEP-based product models are well defined and syntactically correct, populating product data according to these models is not easy because they are too big and disorganized. Data exchange specifications (DEXs) and templates provide re-organized information models required in data exchange of specific activities for various businesses. DEXs show us it would be possible to organize STEP-based product models in order to support different engineering activities at various stages of product life-cycle. In this study, STEP-based models are enriched and organized to support two engineering activities: materials information declaration and tolerance analysis. Due to new environmental regulations, the substance and materials information in products have to be screened closely by manufacturing industries. This requires a fast, unambiguous and complete product information exchange between the members of a supply chain. Tolerance analysis activity, on the other hand, is used to verify the functional requirements of an assembly considering the worst case (i.e., maximum and minimum) conditions for the part/assembly dimensions. Another issue with STEP-based product models is that the semantics of product data are represented implicitly. Hence, it is difficult to interpret the semantics of data for different product life-cycle phases for various application domains. OntoSTEP, developed at NIST, provides semantically enriched product models in OWL. In this thesis, we would like to present how to interpret the GD & T specifications in STEP for tolerance analysis by utilizing OntoSTEP.

  3. Exploration of Possible Astroblemes in the Argentine Puna

    NASA Astrophysics Data System (ADS)

    Acevedo, R. D.; Alonso, R.; Rocca, M.; Klajnik, K.; Tálamo, E.

    2014-09-01

    Potential three new astrobleme sites have been detected by remote sensors and checked in situ in Argentine Puna: an elevated plateau that it has remained stable and invariable across long geological periods.

  4. A Descriptive Study of the Argentine Music Teacher.

    ERIC Educational Resources Information Center

    Gratzer, Dina; Sima, Marta

    1987-01-01

    Reports on a research study which examined the professional status of music teachers in Argentina. Describes various areas of concern for Argentine music teachers including general training, the workplace, teacher training and musical activities. (RKM)

  5. Life cycle assessment of gasoline production and use in Chile.

    PubMed

    Morales, Marjorie; Gonzalez-García, Sara; Aroca, Germán; Moreira, María Teresa

    2015-02-01

    Gasoline is the second most consumed fuel in Chile, accounting for 34% of the total fuel consumption in transportation related activities in 2012. Chilean refineries process more than 97% of the total gasoline commercialized in the national market. When it comes to evaluating the environmental profile of a Chilean process or product, the analysis should consider the characteristics of the Chilean scenario for fuel production and use. Therefore, the identification of the environmental impacts of gasoline production turns to be very relevant for the determination of the associated environmental impacts. For this purpose, Life Cycle Assessment has been selected as a useful methodology to assess the ecological burdens derived from fuel-based systems. In this case study, five subsystems were considered under a "well-to-wheel" analysis: crude oil extraction, gasoline importation, refinery, gasoline storage and distribution/use. The distance of 1 km driven by a middle size passenger car was chosen as functional unit. Moreover, volume, economic and energy-based allocations were also considered in a further sensitivity analysis. According to the results, the main hotspots were the refining activities as well as the tailpipe emissions from car use. When detailing by impact category, climate change was mainly affected by the combustion emissions derived from the gasoline use and refining activities. Refinery was also remarkable in toxicity related categories due to heavy metals emissions. In ozone layer and mineral depletion, transport activities played an important role. Refinery was also predominant in photochemical oxidation and water depletion. In terms of terrestrial acidification and marine eutrophication, the combustion emissions from gasoline use accounted for large contributions. This study provides real inventory data for the Chilean case study and the environmental results give insight into their influence of the assessment of products and processes in the country

  6. Life cycle assessment of gasoline production and use in Chile.

    PubMed

    Morales, Marjorie; Gonzalez-García, Sara; Aroca, Germán; Moreira, María Teresa

    2015-02-01

    Gasoline is the second most consumed fuel in Chile, accounting for 34% of the total fuel consumption in transportation related activities in 2012. Chilean refineries process more than 97% of the total gasoline commercialized in the national market. When it comes to evaluating the environmental profile of a Chilean process or product, the analysis should consider the characteristics of the Chilean scenario for fuel production and use. Therefore, the identification of the environmental impacts of gasoline production turns to be very relevant for the determination of the associated environmental impacts. For this purpose, Life Cycle Assessment has been selected as a useful methodology to assess the ecological burdens derived from fuel-based systems. In this case study, five subsystems were considered under a "well-to-wheel" analysis: crude oil extraction, gasoline importation, refinery, gasoline storage and distribution/use. The distance of 1 km driven by a middle size passenger car was chosen as functional unit. Moreover, volume, economic and energy-based allocations were also considered in a further sensitivity analysis. According to the results, the main hotspots were the refining activities as well as the tailpipe emissions from car use. When detailing by impact category, climate change was mainly affected by the combustion emissions derived from the gasoline use and refining activities. Refinery was also remarkable in toxicity related categories due to heavy metals emissions. In ozone layer and mineral depletion, transport activities played an important role. Refinery was also predominant in photochemical oxidation and water depletion. In terms of terrestrial acidification and marine eutrophication, the combustion emissions from gasoline use accounted for large contributions. This study provides real inventory data for the Chilean case study and the environmental results give insight into their influence of the assessment of products and processes in the country

  7. Pheromone disruption of Argentine ant trail integrity

    USGS Publications Warehouse

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  8. Pheromone disruption of Argentine ant trail integrity.

    PubMed

    Suckling, D M; Peck, R W; Manning, L M; Stringer, L D; Cappadonna, J; El-Sayed, A M

    2008-12-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m(2)) to 1- and 4-m(2) plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. PMID:19034574

  9. The Statistical Relationship between Product Life Cycle and Repeat Purchase Behavior in Convenience Stores

    NASA Astrophysics Data System (ADS)

    Mizuno, T.; Takayasu, M.

    The density function of product life cycles in convenience stores is found to follow the Weibull distribution. To clarify the parameters that determine these life cycles, we introduce the conditional market share---defined as the probability that a product is selected by customers only if it had been previously purchased---and the market share without any conditions. The product life cycle is more strongly correlated with the conditional market share of the product than with the latter type of market share.

  10. Exergetic life cycle assessment of hydrogen production from renewables

    NASA Astrophysics Data System (ADS)

    Granovskii, Mikhail; Dincer, Ibrahim; Rosen, Marc A.

    Life cycle assessment is extended to exergetic life cycle assessment and used to evaluate the exergy efficiency, economic effectiveness and environmental impact of producing hydrogen using wind and solar energy in place of fossil fuels. The product hydrogen is considered a fuel for fuel cell vehicles and a substitute for gasoline. Fossil fuel technologies for producing hydrogen from natural gas and gasoline from crude oil are contrasted with options using renewable energy. Exergy efficiencies and greenhouse gas and air pollution emissions are evaluated for all process steps, including crude oil and natural gas pipeline transportation, crude oil distillation and natural gas reforming, wind and solar electricity generation, hydrogen production through water electrolysis, and gasoline and hydrogen distribution and utilization. The use of wind power to produce hydrogen via electrolysis, and its application in a fuel cell vehicle, exhibits the lowest fossil and mineral resource consumption rate. However, the economic attractiveness, as measured by a "capital investment effectiveness factor," of renewable technologies depends significantly on the ratio of costs for hydrogen and natural gas. At the present cost ratio of about 2 (per unit of lower heating value or exergy), capital investments are about five times lower to produce hydrogen via natural gas rather than wind energy. As a consequence, the cost of wind- and solar-based electricity and hydrogen is substantially higher than that of natural gas. The implementation of a hydrogen fuel cell instead of an internal combustion engine permits, theoretically, an increase in a vehicle's engine efficiency of about of two times. Depending on the ratio in engine efficiencies, the substitution of gasoline with "renewable" hydrogen leads to (a) greenhouse gas (GHG) emissions reductions of 12-23 times for hydrogen from wind and 5-8 times for hydrogen from solar energy, and (b) air pollution (AP) emissions reductions of 38

  11. Carbohydrate supply limits invasion of natural communities by Argentine ants.

    PubMed

    Rowles, Alexei D; Silverman, Jules

    2009-08-01

    The ability of species to invade new habitats is often limited by various biotic and physical factors or interactions between the two. Invasive ants, frequently associated with human activities, flourish in disturbed urban and agricultural environments. However, their ability to invade and establish in natural habitats is more variable. This is particularly so for the invasive Argentine ant (Linepithema humile). While biotic resistance and low soil moisture limits their invasion of natural habitats in some instances, the effect of food availability has been poorly explored. We conducted field experiments to determine if resource availability limits the spread and persistence of Argentine ants in remnant natural forest in North Carolina. Replicated transects paired with and without sucrose solution feeding stations were run from invaded urban edges into forest remnants and compared over time using baits and direct counts at feeding stations. Repeated under different timing regimes in 2006 and 2007, access to sucrose increased local Argentine ant abundances (1.6-2.5 fold) and facilitated their progression into the forest up to 73 +/- 21% of 50-m transects. Resource removal caused an expected decrease in Argentine ant densities in 2006, in conjunction with their retreat to the urban/forest boundary. However, in 2007, Argentine ant numbers unexpectedly continued to increase in the absence of sugar stations, possibly through access to alternative resources or conditions not available the previous year such as honeydew-excreting Hemiptera. Our results showed that supplementing carbohydrate supply facilitates invasion of natural habitat by Argentine ants. This is particularly evident where Argentine ants continued to thrive following sugar station removal.

  12. Simultaneous production of desalinated water and power using a hybrid-cycle OTEC plant

    SciTech Connect

    Panchal, C.B.; Bell, K.J.

    1987-05-01

    A systems study for simultaneous production of desalinated water and electric power using the hybrid-cycle OTEC system was carried out. The hybrid cycle is a combination of open and closed-cycle OTEC systems. A 10 MWe shore-based hybrid-cycle OTEC plant is discussed and corresponding operating parameters are presented. Design and plant operating criteria for adjusting the ratio of water production to power generation are described and their effects on the total system were evaluated. The systems study showed technical advantages of the hybrid-cycle power system as compared to other leading OTEC systems for simultaneous production of desalinated water and electric power generation.

  13. Contribution of cyanobacterial alkane production to the ocean hydrocarbon cycle.

    PubMed

    Lea-Smith, David J; Biller, Steven J; Davey, Matthew P; Cotton, Charles A R; Perez Sepulveda, Blanca M; Turchyn, Alexandra V; Scanlan, David J; Smith, Alison G; Chisholm, Sallie W; Howe, Christopher J

    2015-11-01

    Hydrocarbons are ubiquitous in the ocean, where alkanes such as pentadecane and heptadecane can be found even in waters minimally polluted with crude oil. Populations of hydrocarbon-degrading bacteria, which are responsible for the turnover of these compounds, are also found throughout marine systems, including in unpolluted waters. These observations suggest the existence of an unknown and widespread source of hydrocarbons in the oceans. Here, we report that strains of the two most abundant marine cyanobacteria, Prochlorococcus and Synechococcus, produce and accumulate hydrocarbons, predominantly C15 and C17 alkanes, between 0.022 and 0.368% of dry cell weight. Based on global population sizes and turnover rates, we estimate that these species have the capacity to produce 2-540 pg alkanes per mL per day, which translates into a global ocean yield of ∼ 308-771 million tons of hydrocarbons annually. We also demonstrate that both obligate and facultative marine hydrocarbon-degrading bacteria can consume cyanobacterial alkanes, which likely prevents these hydrocarbons from accumulating in the environment. Our findings implicate cyanobacteria and hydrocarbon degraders as key players in a notable internal hydrocarbon cycle within the upper ocean, where alkanes are continually produced and subsequently consumed within days. Furthermore we show that cyanobacterial alkane production is likely sufficient to sustain populations of hydrocarbon-degrading bacteria, whose abundances can rapidly expand upon localized release of crude oil from natural seepage and human activities.

  14. Contribution of cyanobacterial alkane production to the ocean hydrocarbon cycle

    PubMed Central

    Lea-Smith, David J.; Biller, Steven J.; Davey, Matthew P.; Cotton, Charles A. R.; Perez Sepulveda, Blanca M.; Turchyn, Alexandra V.; Scanlan, David J.; Smith, Alison G.; Chisholm, Sallie W.; Howe, Christopher J.

    2015-01-01

    Hydrocarbons are ubiquitous in the ocean, where alkanes such as pentadecane and heptadecane can be found even in waters minimally polluted with crude oil. Populations of hydrocarbon-degrading bacteria, which are responsible for the turnover of these compounds, are also found throughout marine systems, including in unpolluted waters. These observations suggest the existence of an unknown and widespread source of hydrocarbons in the oceans. Here, we report that strains of the two most abundant marine cyanobacteria, Prochlorococcus and Synechococcus, produce and accumulate hydrocarbons, predominantly C15 and C17 alkanes, between 0.022 and 0.368% of dry cell weight. Based on global population sizes and turnover rates, we estimate that these species have the capacity to produce 2–540 pg alkanes per mL per day, which translates into a global ocean yield of ∼308–771 million tons of hydrocarbons annually. We also demonstrate that both obligate and facultative marine hydrocarbon-degrading bacteria can consume cyanobacterial alkanes, which likely prevents these hydrocarbons from accumulating in the environment. Our findings implicate cyanobacteria and hydrocarbon degraders as key players in a notable internal hydrocarbon cycle within the upper ocean, where alkanes are continually produced and subsequently consumed within days. Furthermore we show that cyanobacterial alkane production is likely sufficient to sustain populations of hydrocarbon-degrading bacteria, whose abundances can rapidly expand upon localized release of crude oil from natural seepage and human activities. PMID:26438854

  15. Life cycle and landscape impacts of biofuel production

    NASA Astrophysics Data System (ADS)

    Hill, J.

    2012-12-01

    Achieving the biofuel volumes mandated in the Renewable Fuels Standard of the United States Energy Independence and Security Act of 2007 will require large amounts of biomass such as crop residues and dedicated bioenergy crops. Growing sufficient amounts of these feedstocks would greatly transform the agricultural landscape of the United States, and depending on where and how they are grown, may have vastly different implications for the sustainability of the biofuels industry. This presentation describes ongoing research into how biomass can best be produced on the landscape so as to benefit rural economies and provide ecosystem services such as greenhouse gas mitigation and improved air quality. The focus is on newly developed methods for integrating spatial and temporal information into life cycle assessment so as to both allow for more detailed impact assessment and to provide insight into how to improve efficiency along bioenergy production supply chains. Results will benefit stakeholders both by offering recommendations for guiding sustainable growth of the emerging bioeconomy and by advancing understanding of the inherent tradeoffs among alternate scenarios.

  16. Combined cycle energy production: Overview of worldwide utilization and techniques

    NASA Astrophysics Data System (ADS)

    Roche, M.

    1982-06-01

    The worldwide distribution of combined cycle generators using simple recuperation, supercharged boilers, post combustion, and parallel combustion and complex cycles is summarized. Clean energy, fuel oil, coal, fluidized bed, and gasification based processes are discussed. With clean energy systems, up to 46% efficiency is achieved using a single recuperation - double evaporation cycle. Using gas turbine output to feed a higher power steam turbine is also economically attractive, but no one system is an obvious choice. Around 100 combined generators are now operating.

  17. Response of Argentine ants and red imported fire ants to permethrin-impregnated plastic strips: foraging rates, colonization of potted soil, and differential mortality.

    PubMed

    Costa, Heather S; Greenberg, Les; Klotz, John; Rust, Michael K

    2005-12-01

    This study investigated the effects of the permethrin-impregnated plastic on ant mortality and foraging rates, and tested its potential for preventing ants from colonizing potted soil. Direct exposure to the plastic for as short as 1 min caused significant mortality of both red imported fire ants, Solenopsis invicta Buren, and Argentine ants, Linepithema humile (Mayr); however, red imported fire ants were more susceptible than Argentine ants. Knockdown of virtually all ants initially occurred within 15 min after exposure. However, some moribund ants recovered from the effects within 24 h. For example, after 1 min of direct exposure to the permethrin-impregnated plastic, 70% of Argentine ants and 5% of red imported fire ants recovered from the treatment. In established colonies of Argentine ants, significantly fewer ants foraged for food up posts treated with the plastic compared with untreated posts. In addition, colonies responded to introduction of the treatment by significantly reducing their overall foraging rates, even on untreated posts. When pots filled with moistened soil were introduced into established ant colonies, 82% of Argentine ants and 99% of red imported fire ants moved into the soil. In contrast, when a 1-cm-wide coil of the plastic was placed under the pot, no ants moved into the soil. The potential for use of these materials in nursery production is discussed. PMID:16539136

  18. Productivity and nutrient cycling in bioenergy cropping systems

    NASA Astrophysics Data System (ADS)

    Heggenstaller, Andrew Howard

    One of the greatest obstacles confronting large-scale biomass production for energy applications is the development of cropping systems that balance the need for increased productive capacity with the maintenance of other critical ecosystem functions including nutrient cycling and retention. To address questions of productivity and nutrient dynamics in bioenergy cropping systems, we conducted two sets of field experiments during 2005-2007, investigating annual and perennial cropping systems designed to generate biomass energy feedstocks. In the first experiment we evaluated productivity and crop and soil nutrient dynamics in three prototypical bioenergy double-crop systems, and in a conventionally managed sole-crop corn system. Double-cropping systems included fall-seeded forage triticale (x Triticosecale Wittmack), succeeded by one of three summer-adapted crops: corn (Zea mays L.), sorghum-sudangrass [Sorghum bicolor (L.) Moench], or sunn hemp (Crotalaria juncea L.). Total dry matter production was greater for triticale/corn and triticale/sorghum-sudangrass compared to sole-crop corn. Functional growth analysis revealed that photosynthetic duration was more important than photosynthetic efficiency in determining biomass productivity of sole-crop corn and double-crop triticale/corn, and that greater yield in the tiritcale/corn system was the outcome of photosynthesis occurring over an extended duration. Increased growth duration in double-crop systems was also associated with reductions in potentially leachable soil nitrogen relative to sole-crop corn. However, nutrient removal in harvested biomass was also greater in the double-crop systems, indicating that over the long-term, double-cropping would mandate increased fertilizer inputs. In a second experiment we assessed the effects of N fertilization on biomass and nutrient partitioning between aboveground and belowground crop components, and on carbon storage by four perennial, warm-season grasses: big bluestem

  19. 75 FR 21632 - Draft Guidance for Industry and Food and Drug Administration Staff; Total Product Life Cycle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-26

    ... Staff; Total Product Life Cycle: Infusion Pump--Premarket Notification Submissions; Availability AGENCY... announcing the availability of the draft guidance document entitled ``Total Product Life Cycle: Infusion Pump... Life Cycle: Infusion Pump-- Premarket Notification Submissions'' to the Division of Small...

  20. Production and Cycling of Methylmercury in High Arctic Wetland Ponds

    NASA Astrophysics Data System (ADS)

    Lehnherr, I.; St. Louis, V. L.

    2010-12-01

    Some species of freshwater fish in the Canadian high Arctic contain levels of methylmercury (MeHg) that pose health risks to the northern Inuit peoples that harvest these species as a traditional food source. In temperate regions, wetlands are known natural sites of MeHg production and hence significant MeHg sources to downstream ecosystems. However, the importance of wetlands to Hg methylation in the Arctic is unclear and the sources of MeHg to arctic freshwater ecosystems are still largely unidentified. Our research is demonstrating that some shallow and warm wetland ponds on the Arctic landscape contain high MeHg concentrations compared to nearby deep and cold lakes. We used a mass-balance approach to measure the net in-pond production of MeHg in two warm wetland ponds (Ponds 1 and 2) near Lake Hazen, Ellesmere Island, Nunavut (81° N latitude). We quantified external inputs and outputs of MeHg to and from the ponds, as well as the accumulation of MeHg in the water column during the summers of 2005 and 2008. Any changes in water column MeHg concentrations that could not be accounted for by external inputs or sinks were attributed to in-pond production. The principal external input and sink of MeHg was, respectively, wet atmospheric deposition and water-column MeHg photodemethylation. For 2005, we estimate that the net flux of MeHg from sediments into the water column was 0.015 μg m-2 d-1 in Pond 1 and 0.0016 μg m-2 d-1 in Pond 2. Compared to sediment-water MeHg fluxes measured in Alaskan tundra lakes (0.0015-0.0045 μg m-2 d-1), Pond 1 sediments are a greater source of MeHg while Pond 2 is similar to the Alaskan lakes. Furthermore, the accumulation of MeHg in the water column of Pond 1 (0.0061 μg m-2 d-1) was similar to the net yield of MeHg from temperate boreal wetlands (0.0005-0.006 μg m-2 d-1), demonstrating that these Arctic wetlands are important sites of MeHg production. In addition, we used mercury stable-isotope tracers to quantify methylation and

  1. [The Argentine Health System: organization and financial features].

    PubMed

    Arce, Hugo E

    2012-01-01

    The Argentine health system is defined by the following features: a) federal country organization; b) coexistence of public and private services with either outpatients or inpatients; c) fragmented entities of social security, most of these originated outside of the state organization. Components of the system are described and weighed; making decisions strength between national and provincial health authorities is analyzed and the Argentine system is compared with that of other countries. Statistical data on distribution of health expenditures and coverage of health services are presented as well as financial flow among diverse funding sources, insurers, providers and users of each sector. PMID:23089118

  2. Integrated Metrics for Improving the Life Cycle Approach to Assessing Product System Sustainability

    EPA Science Inventory

    Life cycle approaches are critical for identifying and managing to reduce burdens in the sustainability of product systems. While these methods can indicate potential environmental impacts of a product, current Life Cycle Assessment (LCA) methods fail to integrate the multiple im...

  3. 76 FR 34271 - Hewlett Packard, Global Parts Supply Chain, Global Product Life Cycles Management Unit, Including...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-13

    ... Employment and Training Administration Hewlett Packard, Global Parts Supply Chain, Global Product Life Cycles... workers of Hewlett Packard, Global Parts Supply Chain, Global Product Life Cycles Management Unit... was published in the Federal Register on November 23, 2010 (75 FR 71460). At the request of the...

  4. Controls on silicon cycling in Southeast Asian rice production systems

    NASA Astrophysics Data System (ADS)

    Klotzbücher, Thimo; Marxen, Anika; Vetterlein, Doris; Jahn, Reinhold

    2013-04-01

    Recent research suggests that silicon (Si) is beneficial for rice plants, i.e., a sufficient Si supply improves their resistance against pests and pathogens and increases the uptake of essential nutrients. Despite its potential importance for rice yields, cycling of Si in rice production systems is poorly studied. We assess plant-available Si (Sipa; determined using acetate extraction) in topsoils (Ap+Arp horizons) and Si uptake by plants at 70 paddy fields managed by local farmers in contrasting regions of Vietnam and the Philippines. First results show that Sipa contents are considerably larger in Philippine (217 ± 100 mg Sipa kg-1 ) than in Vietnamese (32 ± 19 mg Sipa kg-1) paddy soils. Rice straw from the Philippines contains 8.6 ± 0.9 % Si, straw from Vietnam 5.0 ± 1.2 % Si. Laboratory experiments showed that Si is limiting the growth of rice plants in some of the Vietnamese soils. We assume that differences in geo-/ pedologic conditions between Vietnam and the Philippines explain the data. Large Sipa contents in the Philippine soils are due to recent rock formation by active volcanism, hence, by a large Sipa input due to mineral weathering in recent geologic history. In contrast, parent materials of the Vietnamese paddy soils derive from old and highly weathered land surfaces. Hence, our data suggest that geo-/pedologic conditions are the main control for the availability of Si in paddy soils. Currently, we examine the relevance of agricultural practices for small-scale differences in the availability of Si within regions. Inadequate practices, such as removal of rice straw from the fields, might deplete Sipa in paddy soils causing a decrease in rice yields in some regions of Vietnam. We investigate the role of phytoliths (amorphous Si bodies contained in rice straw) as source of Sipa in paddy soils. Our methods include laboratory experiments and the assessment of turnover times of phytoliths in paddy soils; first results will be presented and discussed

  5. Computational study of productive and non-productive cycles in fluoroalkene metathesis

    PubMed Central

    Rybáčková, Markéta; Hošek, Jan; Šimůnek, Ondřej; Kolaříková, Viola

    2015-01-01

    Summary A detailed DFT study of the mechanism of metathesis of fluoroethene, 1-fluoroethene, 1,1-difluoroethene, cis- and trans-1,2-difluoroethene, tetrafluoroethene and chlorotrifluoroethene catalysed with the Hoveyda–Grubbs 2nd generation catalyst was performed. It revealed that a successful metathesis of hydrofluoroethenes is hampered by a high preference for a non-productive catalytic cycle proceeding through a ruthenacyclobutane intermediate bearing fluorines in positions 2 and 4. Moreover, the calculations showed that the cross-metathesis of perfluoro- or perhaloalkenes should be a feasible process and that the metathesis is not very sensitive to stereochemical issues. PMID:26664636

  6. Reducing California's Greenhouse Gas Emissions through ProductLife-Cycle Optimization

    SciTech Connect

    Masanet, Eric; Price, Lynn; de la Rue du Can, Stephane; Worrell,Ernst

    2005-12-30

    Product life-cycle optimization addresses the reduction ofenvironmental burdens associated with the production, use, andend-of-life stages of a product s life cycle. In this paper, we offer anevaluation of the opportunities related to product life-cycleoptimization in California for two key products: personal computers (PCs)and concrete. For each product, we present the results of an explorativecase study to identify specific opportunities for greenhouse gas (GHG)emissions reductions at each stage of the product life cycle. We thenoffer a discussion of the practical policy options that may exist forrealizing the identified GHG reduction opportunities. The case studiesdemonstrate that there may be significant GHG mitigation options as wellas a number of policy options that could lead to life-cycle GHG emissionsreductions for PCs and concrete in California.

  7. Surface Uplift and Erosion of the Southernmost Argentine Precordillera Range, constrained two ways

    NASA Astrophysics Data System (ADS)

    Walcek, A. A.; Hoke, G. D.

    2010-12-01

    Studying the geomorphology of actively deforming mountain ranges in distinct plate tectonic settings provides the potential to unlock important clues related to the growth and destruction of topography. We work here to estimate the timing and magnitude of uplift in the southern Argentine Precordillera by quantifying the response of the landscape to uplift. The southern Argentine Precordillera retains vast remnants of a paleolandscape, which are broad areas of pre-uplift topography. The exposure history of these desert pavement surfaces can provide information on the uplift history of the area. The locations of the paleosurfaces, clearly visible in the Argentine Precordillera, have been mapped using satellite images and digital elevation models with confirmation in the field. This map provides valuable information about the extent to which the surfaces have been eroded. All rivers draining the paleolandscape are bounded by pronounced knickpoints. The downstream projection of stream profiles that originate above the major knickpoints provide an independent constraint on the magnitude of surface uplift due to the predictable relationship between drainage area and channel slope. The erosion rates above and below knickpoints were measured from stream sediment using the cosmogenic nuclides 26Al and 10Be. The erosion rates below the knickpoint show order of magnitude differences in erosion rates than those above. Using the cosmogenic nuclides 26Al, 10Be, and 21Ne measured from surface samples of desert pavements, we estimate the uplift history of the paleosurfaces through modeling various uplift histories and their corresponding cosmogenic nuclide production rates. From multiple nuclides, both age and erosion rate is determined. The preliminary 21Ne data shows that the paleosurfaces are older than 1 Ma and slowly eroding at less than 10 m/Ma, with a second population of ages around 300,000 years. However, since the area has been uplifted, the elevation is changing through

  8. The Mindful Attention Awareness Scale (MAAS) in an Argentine Population

    ERIC Educational Resources Information Center

    Montes, Silvana Andrea; Ledesma, Rubén Daniel; García, Natalia Mariana; Poó, Fernando Martín

    2014-01-01

    The purpose of this study was to provide evidence of validity for the Mindful Attention Awareness Scale scores in an Argentine sample (Spanish-language version). Results indicated satisfactory psychometric properties (a one-factor structure, good item discrimination, high reliability, and significant correlations with additional measures). This…

  9. Different Argentine Rural Extensionists' Mindsets and Their Practical Implications

    ERIC Educational Resources Information Center

    Landini, Fernando

    2015-01-01

    Purpose: This paper reflects upon the practice of Argentine rural extensionists working in the extension public system through the process of identifying different rural extensionists' types of mindsets and comparing them with transfer of technology extension approach, dialogical processes of horizontal knowledge exchange, participatory…

  10. Glacial cycles drive variations in the production of oceanic crust.

    PubMed

    Crowley, John W; Katz, Richard F; Huybers, Peter; Langmuir, Charles H; Park, Sung-Hyun

    2015-03-13

    Glacial cycles redistribute water between oceans and continents, causing pressure changes in the upper mantle, with consequences for the melting of Earth's interior. Using Plio-Pleistocene sea-level variations as a forcing function, theoretical models of mid-ocean ridge dynamics that include melt transport predict temporal variations in crustal thickness of hundreds of meters. New bathymetry from the Australian-Antarctic ridge shows statistically significant spectral energy near the Milankovitch periods of 23, 41, and 100 thousand years, which is consistent with model predictions. These results suggest that abyssal hills, one of the most common bathymetric features on Earth, record the magmatic response to changes in sea level. The models and data support a link between glacial cycles at the surface and mantle melting at depth, recorded in the bathymetric fabric of the sea floor. PMID:25766231

  11. Portrayals of character smoking and drinking in Argentine-, Mexican- and US-produced films.

    PubMed

    Kollath-Cattano, Christy; Abad-Vivero, Erika N; Mejia, Raul; Perez-Hernandez, Rosaura; Sargent, James D; Thrasher, James F

    2016-09-01

    The aim of this study was to assess film character portrayals of tobacco and alcohol use in US and nationally-produced films that were popular in Argentina and Mexico from 2004-2012. We performed a content analysis of these films (n=82 Argentine, 91 Mexican, and 908 US films, respectively). Chi-squares and t-tests were used to compare characteristics of characters who smoked or drank by country of movie production. Then data from all countries were pooled, and generalized estimating equation (GEE) models were used to determine independent correlates of character smoking or drinking. There were 480 major characters for Argentine-, 364 for Mexican-, and 4962 for US-produced films. Smoking prevalence among movie characters was similar to population smoking prevalence in Mexico (21%) and Argentina (26%), but about half in the US (11%), where movie product placements are restricted. Movie smoking declined over the period in all three countries. Movie alcohol prevalence was 40-50% across all countries and did not change with time. Demographic predictors of character smoking included: being male, 18 and older, having negative character valence. Movie smoking was not associated with lower SES. Predictors of character drinking included: being age 18 and older and positive character valence. Smoking and drinking predicted each other, illicit drug use, and higher scores for other risk behaviors. This suggests that policy development in Mexico and Argentina may be necessary to reduce the amount of character tobacco and alcohol use in films. PMID:27404576

  12. Thermochemical cycles

    NASA Technical Reports Server (NTRS)

    Funk, J. E.; Soliman, M. A.; Carty, R. H.; Conger, W. L.; Cox, K. E.; Lawson, D.

    1975-01-01

    The thermochemical production of hydrogen is described along with the HYDRGN computer program which attempts to rate the various thermochemical cycles. Specific thermochemical cycles discussed include: iron sulfur cycle; iron chloride cycle; and hybrid sulfuric acid cycle.

  13. The Argentine ant persists through unfavorable winters via a mutualism facilitated by a native tree.

    PubMed

    Brightwell, Robert J; Silverman, Jules

    2011-10-01

    Mutualisms and facilitations can fundamentally change the relationship between an organism's realized and fundamental niche. Invasive species may prove particularly suitable models for investigating this relationship as many are dependent on finding new partners for successful establishment. We conducted field-based experiments testing whether a native tree facilitates the successful survival of the invasive Argentine ant, Linepithema humile (Mayr), through unfavorable winter conditions in the southeastern United States. We found Argentine ant nests aggregated around the native loblolly pine, Pinus taeda L., during the winter months. The bark of this tree absorbed enough radiant solar energy to reach temperatures suitable for Argentine ant foraging even when ambient temperatures should have curtailed all foraging. Conversely, foraging ceased when the trunk was shaded. The sun-warmed bark of this tree gave the Argentine ant access to a stable honeydew resource. Argentine ants were not found on or near deciduous trees even though bark temperatures were warm enough to permit Argentine ant foraging on cold winter days. Augmenting deciduous trees with sucrose water through the winter months lead to Argentine ant nests remaining at their base and Argentine ants foraging on the tree. The Argentine ant requires both foraging opportunity and a reliable winter food source to survive through unfavorable winter conditions in the southeastern United States. The loblolly pine provided both of these requirements extending the realized niche of Argentine ants beyond its fundamental niche.

  14. Improving Knowledge for Green Textile Products: Life Cycle Analysis

    ERIC Educational Resources Information Center

    Nam, Jinhee

    2012-01-01

    Textile products are used heavily every day. The apparel industry is one of the largest industrial polluters, causing damage to both human health and the environment. Despite increasing consumer concern about environmental issues and a growing trend toward supporting sustainable production, consumers are often unable to evaluate accurately which…

  15. Methane-methanol cycle for the thermochemical production of hydrogen

    DOEpatents

    Dreyfuss, Robert M.; Hickman, Robert G.

    1976-01-01

    A thermochemical reaction cycle for the generation of hydrogen from water comprising the following sequence of reactions wherein M represents a metal: CH.sub.4 + H.sub.2 O .fwdarw. CO + 3H.sub.2 (1) co + 2h.sub.2 .fwdarw. ch.sub.3 oh (2) ch.sub.3 oh + so.sub.2 + mo .fwdarw. mso.sub.4 + ch.sub.4 (3) mso.sub.4 .fwdarw. mo + so.sub.2 + 1/2o.sub.2 (4) the net reaction is the decomposition of water into hydrogen and oxygen.

  16. Self-cycling operation increases productivity of recombinant protein in Escherichia coli.

    PubMed

    Storms, Zachary J; Brown, Tobin; Sauvageau, Dominic; Cooper, David G

    2012-09-01

    Self-cycling fermentation (SCF), a cyclical, semi-continuous process that induces cell synchrony, was incorporated into a recombinant protein production scheme. Escherichia coli CY15050, a lac(-) mutant lysogenized with temperature-sensitive phage λ modified to over-express β-galactosidase, was used as a model system. The production scheme was divided into two de-coupled stages. The host cells were cultured under SCF operation in the first stage before being brought to a second stage where protein production was induced. In the first stage, the host strain demonstrated a stable cycling pattern immediately following the first cycle. This reproducible pattern was maintained over the course of the experiments and a significant degree of cell synchrony was obtained. By growing cells using SCF, productivity increased 50% and production time decreased by 40% compared to a batch culture under similar conditions. In addition, synchronized cultures induced from the end of a SCF cycle displayed shorter lysis times and a more complete culture-wide lysis than unsynchronized cultures. Finally, protein synthesis was influenced by the time at which the lytic phase was induced in the cell life cycle. For example, induction of a synchronized culture immediately prior to cell division resulted in the maximum protein productivity, suggesting protein production can be optimized with respect to the cell life cycle using SCF. PMID:22407770

  17. Ocean fronts drive marine fishery production and biogeochemical cycling.

    PubMed

    Woodson, C Brock; Litvin, Steven Y

    2015-02-10

    Long-term changes in nutrient supply and primary production reportedly foreshadow substantial declines in global marine fishery production. These declines combined with current overfishing, habitat degradation, and pollution paint a grim picture for the future of marine fisheries and ecosystems. However, current models forecasting such declines do not account for the effects of ocean fronts as biogeochemical hotspots. Here we apply a fundamental technique from fluid dynamics to an ecosystem model to show how fronts increase total ecosystem biomass, explain fishery production, cause regime shifts, and contribute significantly to global biogeochemical budgets by channeling nutrients through alternate trophic pathways. We then illustrate how ocean fronts affect fishery abundance and yield, using long-term records of anchovy-sardine regimes and salmon abundances in the California Current. These results elucidate the fundamental importance of biophysical coupling as a driver of bottom-up vs. top-down regulation and high productivity in marine ecosystems. PMID:25624488

  18. Ocean fronts drive marine fishery production and biogeochemical cycling

    PubMed Central

    Woodson, C. Brock; Litvin, Steven Y.

    2015-01-01

    Long-term changes in nutrient supply and primary production reportedly foreshadow substantial declines in global marine fishery production. These declines combined with current overfishing, habitat degradation, and pollution paint a grim picture for the future of marine fisheries and ecosystems. However, current models forecasting such declines do not account for the effects of ocean fronts as biogeochemical hotspots. Here we apply a fundamental technique from fluid dynamics to an ecosystem model to show how fronts increase total ecosystem biomass, explain fishery production, cause regime shifts, and contribute significantly to global biogeochemical budgets by channeling nutrients through alternate trophic pathways. We then illustrate how ocean fronts affect fishery abundance and yield, using long-term records of anchovy–sardine regimes and salmon abundances in the California Current. These results elucidate the fundamental importance of biophysical coupling as a driver of bottom–up vs. top–down regulation and high productivity in marine ecosystems. PMID:25624488

  19. Ocean fronts drive marine fishery production and biogeochemical cycling.

    PubMed

    Woodson, C Brock; Litvin, Steven Y

    2015-02-10

    Long-term changes in nutrient supply and primary production reportedly foreshadow substantial declines in global marine fishery production. These declines combined with current overfishing, habitat degradation, and pollution paint a grim picture for the future of marine fisheries and ecosystems. However, current models forecasting such declines do not account for the effects of ocean fronts as biogeochemical hotspots. Here we apply a fundamental technique from fluid dynamics to an ecosystem model to show how fronts increase total ecosystem biomass, explain fishery production, cause regime shifts, and contribute significantly to global biogeochemical budgets by channeling nutrients through alternate trophic pathways. We then illustrate how ocean fronts affect fishery abundance and yield, using long-term records of anchovy-sardine regimes and salmon abundances in the California Current. These results elucidate the fundamental importance of biophysical coupling as a driver of bottom-up vs. top-down regulation and high productivity in marine ecosystems.

  20. Energy and nutrient cycling in pig production systems

    NASA Astrophysics Data System (ADS)

    Lammers, Peter J.

    United States pig production is centered in Iowa and is a major influence on the economic and ecological condition of that community. A pig production system includes buildings, equipment, production of feed ingredients, feed processing, and nutrient management. Although feed is the largest single input into a pig production system, nearly 30% of the non-solar energy use of a conventional--mechanically ventilated buildings with liquid manure handling--pig production system is associated with constructing and operating the pig facility. Using bedded hoop barns for gestating sows and grow-finish pigs reduces construction resource use and construction costs of pig production systems. The hoop based systems also requires approximately 40% less non-solar energy to operate as the conventional system although hoop barn-based systems may require more feed. The total non-solar energy input associated with one 136 kg pig produced in a conventional farrow-to-finish system in Iowa and fed a typical corn-soybean meal diet that includes synthetic lysine and exogenous phytase is 967.9 MJ. Consuming the non-solar energy results in emissions of 79.8 kg CO2 equivalents. Alternatively producing the same pig in a system using bedded hoop barns for gestating sows and grow-finish pigs requires 939.8 MJ/pig and results in emission of 70.2 kg CO2 equivalents, a reduction of 3 and 12% respectively. Hoop barn-based swine production systems can be managed to use similar or less resources than conventional confinement systems. As we strive to optimally allocate non-solar energy reserves and limited resources, support for examining and improving alternative systems is warranted.

  1. Open Cycle OTEC System with Fresh Water Product

    NASA Astrophysics Data System (ADS)

    Amano, Masatugu; Tanaka, Tadayosi

    An open-cycle ocean thermal energy conversion (OC-OTEC) system is one of energy conversion methods to generate electricity from ocean thermal energy. For OC-OTEC system, steam evaporated from the surface seawater due to flash evaporation drives the turbine. At that time, dissolved gas such as air is introduced into the low-pressure system (OC-OTEC system) as the non-condensable gas, which degrades the performance of condensation heat transfer. In this paper, a small scale OC-OTEC experimental unit experimentally investigates the effect of non-condensable gas on the heat transfer performance in a condenser. The experimental results are discussed in comparison with theoretical estimation by Sparrow-Lin method. It is shown that the condensation is occupied by heat and mass transfer near a condensation surface and that the condensation efficiency is affected by exhaust quantity of non-condensable gas at relative high concentration ratio of condensable gas.

  2. Closed cycle osmotic power plants for electric power production

    NASA Astrophysics Data System (ADS)

    Reali, M.

    1980-04-01

    The paper deals with closed-cycle osmotic power plants (CCOPPs), which are not meant for the exploitation of natural salinity gradients but, rather, for the exploitation of those abundant heat sources having temperatures slightly higher than ambient temperature, e.g., geothermal fields, ocean temperature gradients, waste heat from power plants, and solar energy. The paper gives a general description of the CCOPP, along with some indications of its potential for energy generation. The concept of the CCOPP lies in producing electric power by means of the osmotic flows of suitable solvents and subsequently in separating them again from their solutes by means of thermal energy obtained from any available heat source. The discussion covers osmotic phenomena and the CCOPP, as well as important features of the CCOPP.

  3. Carbonate thermochemical cycle for the production of hydrogen

    DOEpatents

    Collins, Jack L [Knoxville, TN; Dole, Leslie R [Knoxville, TN; Ferrada, Juan J [Knoxville, TN; Forsberg, Charles W [Oak Ridge, TN; Haire, Marvin J [Oak Ridge, TN; Hunt, Rodney D [Oak Ridge, TN; Lewis, Jr, Benjamin E [Knoxville, TN; Wymer, Raymond G [Oak Ridge, TN

    2010-02-23

    The present invention is directed to a thermochemical method for the production of hydrogen from water. The method includes reacting a multi-valent metal oxide, water and a carbonate to produce an alkali metal-multi-valent metal oxide compound, carbon dioxide, and hydrogen.

  4. Spatially Explicit Life Cycle Assessment of Biofuel Feedstock Production

    EPA Science Inventory

    Biofuels derived from renewable resources have gained increased research and development priority due to increasing energy demand and national security concerns. In the US, the Energy Independence and Security Act (EISA) of 2007 mandated the annual production of 56.8 billion L of...

  5. Hydroacoustical evidence of the expansion of pelagic swarms of Munida gregaria (Decapoda, Munididae) in the Beagle Channel and the Argentine Patagonian Shelf, and its relationship with habitat features

    NASA Astrophysics Data System (ADS)

    Diez, Mariano J.; Cabreira, Ariel G.; Madirolas, Adrián; Lovrich, Gustavo A.

    2016-08-01

    Squat lobsters are highly diversified and widespread decapods, of which only three species form pelagic swarms. Here we infer the expansion of Munida gregaria populations in the Beagle Channel and the Argentine Patagonian Shelf by means of acoustic surveys of pelagic swarms. We also describe the habitat characteristics in which these swarms occur. Acoustic data was collected during three multidisciplinary scientific cruises on board of the R/V Puerto Deseado during 2009, 2012 and 2014. Despite differences in the environmental conditions between the two surveyed areas, between 2009 and 2014 pelagic swarms increased their occurrence and abundance both in the Beagle Channel and on the Argentine Patagonian Shelf. Towards the end of the studied period, pelagic swarms of M. gregaria occurred in new locations, supporting the notion of a population expansion. Within the Beagle Channel swarm expansions were more marked than on the Patagonian Shelf. We here postulate that M. gregaria expansions occur in association with productive areas of the Argentine continental shelf, such as frontal zones, favoured by the squat lobster phenotypic plasticity that permit to exploit resources in both the neritic and benthic environments. At a regional scale on the Patagonian Shelf, three main groups of pelagic swarms of M. gregaria were clearly associated to respective frontal zones. The information presented here is necessary to understand fluctuations in both distribution and abundance patterns of a key species on the Argentine continental shelf. These fluctuations could be direct or indirect indicators of changes in the ecosystem.

  6. Empowering patients: total product life cycle for medical devices.

    PubMed

    Ciarkowski, Arthur A

    2003-01-01

    Patients today demand a stake in the care of their own health. The expectation is that patients who take responsibility for their own care will communicate more effectively with their health care team and be productive citizens in our society. Medical technology today and those products visible on the horizon, coupled in a telehealth network, provide promise to empower patients to participate fully in the management of their own health. Technology alone, however, will not integrate the elements required for an effective telehealth system. This chapter considers the non-technical matters of this issue such as trends in the medical device industry, trends in the point of care, public health care policies, and the role of government regulation, working together to achieve these public health goals.

  7. Fast and Flexible: Argentine Ants Recruit from Nearby Trails

    PubMed Central

    Flanagan, Tatiana P.; Pinter-Wollman, Noa M.; Moses, Melanie E.; Gordon, Deborah M.

    2013-01-01

    Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources. PMID:23967129

  8. Ribavirin prophylaxis and therapy for experimental argentine hemorrhagic fever.

    PubMed Central

    McKee, K T; Huggins, J W; Trahan, C J; Mahlandt, B G

    1988-01-01

    Junin virus-infected rhesus macaques received prophylactic and therapeutic ribavirin to assess the potential of this drug for treating humans with Argentine hemorrhagic fever. When ribavirin was administered intramuscularly at the time of experimental infection with the lethal P3790 strain of Junin virus, all animals were protected from clinical disease. A delay in the initiation of therapy until after the onset of illness resulted in improvement and resolution of systemic signs of disease; however, survivors subsequently developed a late-onset central nervous system infection which was fatal in two of three animals. Side effects of ribavirin included thrombocytosis and severe anemia, both of which resolved promptly on withdrawal of drug therapy. Results of this study suggest that ribavirin may prove useful in treating humans with Argentine hemorrhagic fever. PMID:2848441

  9. Life-Cycle Assessment of Oilseeds for Biojet Production Using Localized Cold-Press Extraction.

    PubMed

    Sieverding, Heidi L; Zhao, Xianhui; Wei, Lin; Stone, James J

    2016-05-01

    As nonfood oilseed varieties are being rapidly developed, new varieties may affect agricultural production efficiency and life-cycle assessment results. Current, detailed feedstock production information is necessary to accurately assess impacts of the biofuel life-cycle. The life-cycle impacts of four nonfood oilseeds (carinata [ L. Braun], camelina [ L. Crantz], canola or rapeseed [ L.], and sunflower [ L.]) were modeled using Argonne National Laboratory's GREET model to compare feedstocks for renewable biojet production using cold-press oil extraction. Only feedstock-related inputs were varied, allowing isolation of feedstock influence. Carinata and camelina performed slightly better than other oilseed crops at most product stages and impact categories as a result of current, low-input agricultural information and new feedstock varieties. Between 40 to 50% of SO and NO emissions, ∼25% of greenhouse gas (GHG) emissions, and ∼40% of total energy consumption for the biojet production impact occurred during feedstock production. Within the first standard deviation, total well-to-tank emissions varied between ∼13% (GHG) and ∼35% (SO) for all feedstocks emphasizing the importance of accurate agricultural production information. Nonfood oilseed feedstock properties (e.g., oil content, density) and agricultural management (e.g., fertilization, yield) affect life-cycle assessment results. Using biofuels in feedstock production and focusing on low-impact management would assist producers in improving overall product sustainability.

  10. Life-Cycle Assessment of Oilseeds for Biojet Production Using Localized Cold-Press Extraction.

    PubMed

    Sieverding, Heidi L; Zhao, Xianhui; Wei, Lin; Stone, James J

    2016-05-01

    As nonfood oilseed varieties are being rapidly developed, new varieties may affect agricultural production efficiency and life-cycle assessment results. Current, detailed feedstock production information is necessary to accurately assess impacts of the biofuel life-cycle. The life-cycle impacts of four nonfood oilseeds (carinata [ L. Braun], camelina [ L. Crantz], canola or rapeseed [ L.], and sunflower [ L.]) were modeled using Argonne National Laboratory's GREET model to compare feedstocks for renewable biojet production using cold-press oil extraction. Only feedstock-related inputs were varied, allowing isolation of feedstock influence. Carinata and camelina performed slightly better than other oilseed crops at most product stages and impact categories as a result of current, low-input agricultural information and new feedstock varieties. Between 40 to 50% of SO and NO emissions, ∼25% of greenhouse gas (GHG) emissions, and ∼40% of total energy consumption for the biojet production impact occurred during feedstock production. Within the first standard deviation, total well-to-tank emissions varied between ∼13% (GHG) and ∼35% (SO) for all feedstocks emphasizing the importance of accurate agricultural production information. Nonfood oilseed feedstock properties (e.g., oil content, density) and agricultural management (e.g., fertilization, yield) affect life-cycle assessment results. Using biofuels in feedstock production and focusing on low-impact management would assist producers in improving overall product sustainability. PMID:27136164

  11. [Behavior of Argentine lymphocytic choriomeningitis virus strains in rodents].

    PubMed

    Saavedra, María del Cármen; Ambrosio, Ana M; Riera, Laura; Sabattini, Marta S

    2007-01-01

    The activity of LCM virus was first reported in Argentina at the beginning of the seventies and only five strains have been isolated from rodents Mus domesticus and two from humans. The objective of this paper was to find differential biological characteristics of Argentine strains of LCM virus comparing them in relation to the historical strains WE and Armstrong. Regarding the results obtained in tissue culture, when L 929 cells were used, plaque forming units (PFU) were obtained with human and mouse strains, whilst on Vero cells only human strains developed PFU. Differentials characteristics of historical and Argentine strain's plates were not found, neither differences related to the strain's origin. Neither historical nor Argentine strains were lethal to new-born mice giving a persistent infection, that was demonstrated when we inoculated new-born mouse by intracranial route with different strains of LCM virus and virus was isolated from brains harvested at different days post inoculation. The only exception was Cba An 13065 strain that exhibited virulence in new-born mice, only with 0.026 PFU was obtained 1 DL50. All the strains resulted lethal to adult mice. The mouse strains were more virulent than human strains, being Cba An 13065 the most virulent. These results demonstrate a different behavior in tissue culture between human and mouse strains and allow the identification of virulence markers by intracranial inoculation into new-born or adult mice.

  12. Argentine Population Genetic Structure: Large Variance in Amerindian Contribution

    PubMed Central

    Seldin, Michael F.; Tian, Chao; Shigeta, Russell; Scherbarth, Hugo R.; Silva, Gabriel; Belmont, John W.; Kittles, Rick; Gamron, Susana; Allevi, Alberto; Palatnik, Simon A.; Alvarellos, Alejandro; Paira, Sergio; Caprarulo, Cesar; Guillerón, Carolina; Catoggio, Luis J.; Prigione, Cristina; Berbotto, Guillermo A.; García, Mercedes A.; Perandones, Carlos E.; Pons-Estel, Bernardo A.; Alarcon-Riquelme, Marta E.

    2011-01-01

    Argentine population genetic structure was examined using a set of 78 ancestry informative markers (AIMs) to assess the contributions of European, Amerindian, and African ancestry in 94 individuals members of this population. Using the Bayesian clustering algorithm STRUCTURE, the mean European contribution was 78%, the Amerindian contribution was 19.4%, and the African contribution was 2.5%. Similar results were found using weighted least mean square method: European, 80.2%; Amerindian, 18.1%; and African, 1.7%. Consistent with previous studies the current results showed very few individuals (four of 94) with greater than 10% African admixture. Notably, when individual admixture was examined, the Amerindian and European admixture showed a very large variance and individual Amerindian contribution ranged from 1.5 to 84.5% in the 94 individual Argentine subjects. These results indicate that admixture must be considered when clinical epidemiology or case control genetic analyses are studied in this population. Moreover, the current study provides a set of informative SNPs that can be used to ascertain or control for this potentially hidden stratification. In addition, the large variance in admixture proportions in individual Argentine subjects shown by this study suggests that this population is appropriate for future admixture mapping studies. PMID:17177183

  13. Staging Rankine Cycles Using Ammonia for OTEC Power Production

    SciTech Connect

    Bharathan, D.

    2011-03-01

    Recent focus on renewable power production has renewed interest in looking into ocean thermal energy conversion (OTEC) systems. Early studies in OTEC applicability indicate that the island of Hawaii offers a potential market for a nominal 40-MWe system. a 40-MWe system represents a large leap in the current state of OTEC technology. Lockheed Martin Inc. is currently pursuing a more realistic goal of developing a 10-MWe system under U.S. Navy funding (Lockheed 2009). It is essential that the potential risks associated with the first-of-its-kind plant should be minimized for the project's success. Every means for reducing costs must also be pursued without increasing risks. With this in mind, the potential for increasing return on the investment is assessed both in terms of effective use of the seawater resource and of reducing equipment costs.

  14. Life Cycle Assessment as a Tool to Enhance the Environmental Performanceof Carbon Nanotube Products: A Review

    EPA Science Inventory

    The importance of evaluating the environmental performance of emerging carbon nanotube (CNT) products from a life cycle perspective is emphasized in this work. Design, development and deployment of CNT products offer many potential benefits to society, but not without negative im...

  15. Human exposure modeling in a life cycle framework for chemicals and products

    EPA Science Inventory

    A chemical enters into commerce to serve a specific function in a product or process. This decision triggers both the manufacture of the chemical and its potential release over the life cycle of the product. Efficiently evaluating chemical safety and sustainability requires combi...

  16. Cell Cycle Arrest by a Natural Product via G2/M Checkpoint

    PubMed Central

    2005-01-01

    CKBM is a natural product that exhibits a novel anti-tumor activity through the induction of cell cycle arrest and apoptosis. We have investigated its effects on cell cycle regulation using a gastric cancer cell line, AGS. The effects of CKBM on cell proliferation, cell cycle regulation and apoptosis were analyzed using BrdU (5-bromo-2'-deoxyuridine) cell proliferation assay and flow cytometric analysis, respectively. Specific cellular protein expressions were measured using Western blot analysis. Flow cytometric analysis indicated that CKBM induced G2/M cell cycle arrest and apoptosis, whereas differential protein expressions of p21, p53 and 14-3-3σ (stratifin) using Western blot analysis were enhanced. The differential expressions of p21, p53 and 14-3-3σ in AGS cancer cells after CKBM treatment may play critical roles in the G2/M cell cycle arrest that blocks cell proliferation and induces apoptosis. PMID:15968342

  17. Thermodynamic analysis of liquefied natural gas (LNG) production cycle in APCI process

    NASA Astrophysics Data System (ADS)

    Nezhad, Shahrooz Abbasi; Shabani, Bezhan; Soleimani, Majid

    2012-12-01

    The appropriate production of liquefied natural gas (LNG) with least consuming energy and maximum efficiency is quite important. In this paper, LNG production cycle by means of APCI Process has been studied. Energy equilibrium equations and exergy equilibrium equations of each equipment in the APCI cycle were established. The equipments are described using rigorous thermodynamics and no significant simplification is assumed. Taken some operating parameters as key parameters, influences of these parameters on coefficient of performance (COP) and exergy efficiency of the cascading cycle were analyzed. The results indicate that COP and exergy efficiency will be improved with the increasing of the inlet pressure of MR (mixed refrigerant) compressors, the decreasing of the NG and MR after precooling process, outlet pressure of turbine, inlet temperature of MR compressor and NG temperature after cooling in main cryogenic heat exchanger (MCHE). The COP and exergy efficiency of the APCI cycle will be above 2% and 40%, respectively, after optimizing the key parameters.

  18. LIFE CYCLE INVENTORY ANALYSIS IN THE PRODUCTION OF METALS USED IN PHOTOVOLTAICS.

    SciTech Connect

    FTHENAKIS,V.M.; KIM, H.C.; WANG, W.

    2007-03-30

    Material flows and emissions in all the stages of production of zinc, copper, aluminum, cadmium, indium, germanium, gallium, selenium, tellurium, and molybdenum were investigated. These metals are used selectively in the manufacture of solar cells, and emission and energy factors in their production are used in the Life Cycle Analysis (LCA) of photovoltaics. Significant changes have occurred in the production and associated emissions for these metals over the last 10 years, which are not described in the LCA databases. Furthermore, emission and energy factors for several of the by-products of the base metal production were lacking. This report aims in updating the life-cycle inventories associated with the production of the base metals (Zn, Cu, Al, Mo) and in defining the emission and energy allocations for the minor metals (Cd, In, Ge, Se, Te and Ga) used in photovoltaics.

  19. An analysis of hydrogen production via closed-cycle schemes. [thermochemical processings from water

    NASA Technical Reports Server (NTRS)

    Chao, R. E.; Cox, K. E.

    1975-01-01

    A thermodynamic analysis and state-of-the-art review of three basic schemes for production of hydrogen from water: electrolysis, thermal water-splitting, and multi-step thermochemical closed cycles is presented. Criteria for work-saving thermochemical closed-cycle processes are established, and several schemes are reviewed in light of such criteria. An economic analysis is also presented in the context of energy costs.

  20. Mist eliminators for freshwater production from open-cycle OTEC systems

    SciTech Connect

    Bharathan, D.; Penney, T.

    1983-12-01

    For freshwater production from open-cycle OTEC systems, the suitability of commercially available mist eliminators is examined. The mist eliminators are characterized in terms of their liquid collection efficiencies, allowable vapor velocities at the onset of reentrainment, and pressure losses. Suitable design modifications can be projected to allow steam velocities of up to 35 m/s, with a corresponding parasitic power loss of less than 5% of the gross potential of an open-cycle OTEC power system.

  1. Life-cycle energy and environmental analysis of bioethanol production from cassava in Thailand.

    PubMed

    Papong, Seksan; Malakul, Pomthong

    2010-01-01

    In this study, the life-cycle energy and environmental assessment was conducted for bioethanol production from cassava in Thailand. The scope covered all stages in the life cycle of bioethanol production including cultivating, chip processing, transportation and bioethanol conversion. The input-output data were collected at plantation sites and ethanol plants which included materials usage, energy consumption, and all emissions. From the energy analysis, the results show that cassava-based bioethanol has a negative net energy value with an energy ratio was less than 1, indicating a net energy loss. For the environmental performance, the results show that throughout the life cycle of bioethanol, the conversion stage contributes most to the environmental impacts which is due to the use of coal for power and steam production in the bioethanol plants. It is suggested that a partial substitution of coal with biogas produced from existing wastewater treatment could lead to a significant reduction in the environmental impact.

  2. Time-dependent Variation in Life Cycle Assessment of Microalgal Biorefinery Co-products

    NASA Astrophysics Data System (ADS)

    Montazeri, Mahdokht

    Microalgae can serve as a highly productive biological feedstock for fuels and chemicals. The lipid fraction of algal seeds has been the primary target of research for biofuel production. However, numerous assessments have found that valorization of co-products is essential to achieve economic and environmental goals. The relative proportion of co-products depends on the biomolecular composition of algae at the time of harvesting. In the present study the productivity of lipid, starch, and protein fractions were shown through growth experiments to vary widely with species, feeding regime, and harvesting time. Four algae species were cultivated under nitrogen-replete and -deplete conditions and analyzed at regular harvesting intervals. Dynamic growth results were then used for life cycle assessment using the U.S. Department of Energy's GREET model to determine optimal growth scenarios that minimize life cycle greenhouse gas (GHG) emissions, eutrophication, and cumulative energy demand (CED), while aiming for an energy return on investment (EROI) greater than unity. Per kg of biodiesel produced, C. sorokiniana in N-replete conditions harvested at 12 days was most favorable for GHG emissions and CED, despite having a lipid content of <20%. N. oculata under the same conditions had the lowest life cycle eutrophication impacts, driven by efficient nutrient cycling and valorization of microalgal protein and anaerobic digester residue co-products. The results indicate that growth cycle times that maximize a single fraction do not necessarily result in the most favorable environmental performance on a life cycle basis, underscoring the importance of designing biorefinery systems that simultaneously optimize for lipid and non-lipid fractions.

  3. Trail pheromone of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae).

    PubMed

    Choe, Dong-Hwan; Villafuerte, David B; Tsutsui, Neil D

    2012-01-01

    The Argentine ant (Linepithema humile) is recognized as one of the world's most damaging invasive species. One reason for the ecological dominance of introduced Argentine ant populations is their ability to dominate food and habitat resources through the rapid mobilization and recruitment of thousands of workers. More than 30 years ago, studies showed that (Z)-9-hexadecenal strongly attracted Argentine ant workers in a multi-choice olfactometer, suggesting that (Z)-9-hexadecenal might be the trail pheromone, or a component of a trail pheromone mixture. Since then, numerous studies have considered (Z)-9-hexadecenal as the key component of the Argentine ant trails. Here, we report the first chemical analyses of the trails laid by living Argentine ants and find that (Z)-9-hexadecenal is not present in a detectible quantity. Instead, two iridoids, dolichodial and iridomyrmecin, appear to be the primary chemical constituents of the trails. Laboratory choice tests confirmed that Argentine ants were attracted to artificial trails comprised of these two chemicals significantly more often than control trails. Although (Z)-9-hexadecenal was not detected in natural trails, supplementation of artificial dolichodial+iridomyrmecin trails with an extremely low concentraion of (Z)-9-hexadecenal did increase the efficacy of the trail-following behavior. In stark contrast with previous dogma, our study suggests that dolichodial and iridomyrmecin are major components of the Argentine ant trail pheromone. (Z)-9-hexadecenal may act in an additive manner with these iridoids, but it does not occur in detectable quantities in Argentine ant recruitment trails. PMID:23028739

  4. Including indoor offgassed emissions in the life cycle inventories of wood products.

    PubMed

    Chaudhary, Abhishek; Hellweg, Stefanie

    2014-12-16

    Volatile organic compounds (VOCs) that negatively affect human health are emitted from wood products used indoors. However, the existing life cycle inventories of these products only document the emissions occurring during production and disposal phases. Consequently, the life cycle assessment (LCA) of indoor wooden products conducted using these inventories neglect the use-phase impacts from exposure to offgassed VOCs and therefore underestimate the product's total environmental impact. This study demonstrates a methodology to calculate the use phase inventory and the corresponding human health impacts resulting from indoor use of any VOC emitting product. For the five most commonly used types of boards used in indoor wood products, the mass of each VOC emitted into the indoor compartment over their service life was calculated by statistically analyzing data from 50 published chamber testing studies. Uncertainty was assessed using Monte Carlo simulations. The calculated inventory data were used in a case study to calculate and compare the health impacts of five different wooden floorings made of above materials. The results show that the use-phase human-toxicity impacts are an order of magnitude higher than those occurring during the rest of the flooring's life cycle. The factors influencing the offgassing of VOCs from wood products and measures to reduce exposure are discussed.

  5. Including indoor offgassed emissions in the life cycle inventories of wood products.

    PubMed

    Chaudhary, Abhishek; Hellweg, Stefanie

    2014-12-16

    Volatile organic compounds (VOCs) that negatively affect human health are emitted from wood products used indoors. However, the existing life cycle inventories of these products only document the emissions occurring during production and disposal phases. Consequently, the life cycle assessment (LCA) of indoor wooden products conducted using these inventories neglect the use-phase impacts from exposure to offgassed VOCs and therefore underestimate the product's total environmental impact. This study demonstrates a methodology to calculate the use phase inventory and the corresponding human health impacts resulting from indoor use of any VOC emitting product. For the five most commonly used types of boards used in indoor wood products, the mass of each VOC emitted into the indoor compartment over their service life was calculated by statistically analyzing data from 50 published chamber testing studies. Uncertainty was assessed using Monte Carlo simulations. The calculated inventory data were used in a case study to calculate and compare the health impacts of five different wooden floorings made of above materials. The results show that the use-phase human-toxicity impacts are an order of magnitude higher than those occurring during the rest of the flooring's life cycle. The factors influencing the offgassing of VOCs from wood products and measures to reduce exposure are discussed. PMID:25405704

  6. A comprehensive life cycle assessment (LCA) of Jatropha biodiesel production in India.

    PubMed

    Kumar, Sunil; Singh, Jasvinder; Nanoti, S M; Garg, M O

    2012-04-01

    A life cycle approach was adopted for energy, green house gas (GHG) emissions and renewability assessment for production of 1ton of Jatropha biodiesel. Allocation and displacement approaches were applied for life cycle inventory, process energy and process GHG emission attribution to co-products. The results of process energy and GHG emission analyses revealed that the amount of process energy consumption and GHG emission in the individual stages of the life cycle assessment (LCA) were a strong function of co-product handling and irrigation. The GHG emission reduction with respect to petroleum diesel for generating 1GJ energy varied from 40% to 107% and NER values from 1.4 to 8.0 depending upon the methodology used for energy and emission distribution between product and co-products as well as irrigation applied. However, GHG emission reduction values of 54 and 40 and NER (net energy ratio) values of 1.7 and 1.4 for irrigated and rain-fed scenarios, respectively indicate the eco-friendly nature and renewability of biodiesel even in the worst scenario where total life cycle inventory (LCI), process energy and GHG emission were allocated to biodiesel only.

  7. Staphylococcus epidermidis Polysaccharide Intercellular Adhesin Production Significantly Increases during Tricarboxylic Acid Cycle Stress

    PubMed Central

    Vuong, Cuong; Kidder, Joshua B.; Jacobson, Erik R.; Otto, Michael; Proctor, Richard A.; Somerville, Greg A.

    2005-01-01

    Staphylococcal polysaccharide intercellular adhesin (PIA) is important for the development of a mature biofilm. PIA production is increased during growth in a nutrient-replete or iron-limited medium and under conditions of low oxygen availability. Additionally, stress-inducing stimuli such as heat, ethanol, and high concentrations of salt increase the production of PIA. These same environmental conditions are known to repress tricarboxylic acid (TCA) cycle activity, leading us to hypothesize that altering TCA cycle activity would affect PIA production. Culturing Staphylococcus epidermidis with a low concentration of the TCA cycle inhibitor fluorocitrate dramatically increased PIA production without impairing glucose catabolism, the growth rate, or the growth yields. These data lead us to speculate that one mechanism by which staphylococci perceive external environmental change is through alterations in TCA cycle activity leading to changes in the intracellular levels of biosynthetic intermediates, ATP, or the redox status of the cell. These changes in the metabolic status of the bacteria result in the attenuation or augmentation of PIA production. PMID:15838022

  8. Methods Used to Support a Life Cycle of Complex Engineering Products

    NASA Astrophysics Data System (ADS)

    Zakharova, Alexandra A.; Kolegova, Olga A.; Nekrasova, Maria E.; Eremenko, Andrey O.

    2016-08-01

    Management of companies involved in the design, development and operation of complex engineering products recognize the relevance of creating systems for product lifecycle management. A system of methods is proposed to support life cycles of complex engineering products, based on fuzzy set theory and hierarchical analysis. The system of methods serves to demonstrate the grounds for making strategic decisions in an environment of uncertainty, allows the use of expert knowledge, and provides interconnection of decisions at all phases of strategic management and all stages of a complex engineering product lifecycle.

  9. Key issues in life cycle assessment of ethanol production from lignocellulosic biomass: Challenges and perspectives.

    PubMed

    Singh, Anoop; Pant, Deepak; Korres, Nicholas E; Nizami, Abdul-Sattar; Prasad, Shiv; Murphy, Jerry D

    2010-07-01

    Progressive depletion of conventional fossil fuels with increasing energy consumption and greenhouse gas (GHG) emissions have led to a move towards renewable and sustainable energy sources. Lignocellulosic biomass is available in massive quantities and provides enormous potential for bioethanol production. However, to ascertain optimal biofuel strategies, it is necessary to take into account environmental impacts from cradle to grave. Life cycle assessment (LCA) techniques allow detailed analysis of material and energy fluxes on regional and global scales. This includes indirect inputs to the production process and associated wastes and emissions, and the downstream fate of products in the future. At the same time if not used properly, LCA can lead to incorrect and inappropriate actions on the part of industry and/or policy makers. This paper aims to list key issues for quantifying the use of resources and releases to the environment associated with the entire life cycle of lignocellulosic bioethanol production. PMID:20015644

  10. Comparative Life Cycle Assessment of Lignocellulosic Ethanol Production: Biochemical Versus Thermochemical Conversion

    NASA Astrophysics Data System (ADS)

    Mu, Dongyan; Seager, Thomas; Rao, P. Suresh; Zhao, Fu

    2010-10-01

    Lignocellulosic biomass can be converted into ethanol through either biochemical or thermochemical conversion processes. Biochemical conversion involves hydrolysis and fermentation while thermochemical conversion involves gasification and catalytic synthesis. Even though these routes produce comparable amounts of ethanol and have similar energy efficiency at the plant level, little is known about their relative environmental performance from a life cycle perspective. Especially, the indirect impacts, i.e. emissions and resource consumption associated with the production of various process inputs, are largely neglected in previous studies. This article compiles material and energy flow data from process simulation models to develop life cycle inventory and compares the fossil fuel consumption, greenhouse gas emissions, and water consumption of both biomass-to-ethanol production processes. The results are presented in terms of contributions from feedstock, direct, indirect, and co-product credits for four representative biomass feedstocks i.e., wood chips, corn stover, waste paper, and wheat straw. To explore the potentials of the two conversion pathways, different technological scenarios are modeled, including current, 2012 and 2020 technology targets, as well as different production/co-production configurations. The modeling results suggest that biochemical conversion has slightly better performance on greenhouse gas emission and fossil fuel consumption, but that thermochemical conversion has significantly less direct, indirect, and life cycle water consumption. Also, if the thermochemical plant operates as a biorefinery with mixed alcohol co-products separated for chemicals, it has the potential to achieve better performance than biochemical pathway across all environmental impact categories considered due to higher co-product credits associated with chemicals being displaced. The results from this work serve as a starting point for developing full life cycle

  11. Experiencing the Product Life Cycle Management Highs and Lows through Dramatic Simulation

    ERIC Educational Resources Information Center

    Pearce, Glenn; Jackson, John

    2009-01-01

    Product life cycle (PLC) stages and diagrams are briefly and dispassionately covered in the standard marketing textbook format with little attention to the social-psychological experiences of those actually participating. This qualitative study used process drama as a teaching tool and a research instrument to probe the PLC phenomenon in a…

  12. LIFE CYCLE DESIGN GUIDANCE MANUAL - ENVIRONMENTAL REQUIREMENTS AND THE PRODUCT SYSTEM

    EPA Science Inventory

    This document seeks to promote the reduction of environmental impacts and health risks through a systems approach to design. The approach is based on die product life cycle, which includes raw materials acquisition and processing, manufacturing, use/service, resource recovery, an...

  13. LIFE CYCLE DESIGN GUIDANCE MANUAL - ENVIRONMENTAL REQUIREMENTS AND THE PRODUCT SYSTEM

    EPA Science Inventory

    The U.S Environmental Protection Agency's (EPA) Risk Reduction Engineering Laboratory and the University of Michigan are cooperating in a project to reduce environmental impacts and health risks through product system design. The resulting framework for life cycle design is pr...

  14. Thermochemical hydrogen production via a cycle using barium and sulfur - Reaction between barium sulfide and water

    NASA Technical Reports Server (NTRS)

    Ota, K.; Conger, W. L.

    1977-01-01

    The reaction between barium sulfide and water, a reaction found in several sulfur based thermochemical cycles, was investigated kinetically at 653-866 C. Gaseous products were hydrogen and hydrogen sulfide. The rate determining step for hydrogen formation was a surface reaction between barium sulfide and water. An expression was derived for the rate of hydrogen formation.

  15. Effectively Serving the Needs of Today's Business Student: The Product Life Cycle Approach to Class Organization

    ERIC Educational Resources Information Center

    Eastman, Jacqueline K.; Aviles, Maria; Hanna, Mark

    2012-01-01

    We illustrate a class organization process utilizing the concept of the Product Life Cycle to meet the needs of today's millennial student. In the Introduction stage of a business course, professors need to build structure to encourage commitment. In the Growth stage, professors need to promote the structure through multiple, brief activities that…

  16. LIFE CYCLE ASSESSMENT IN MANAGEMENT, PRODUCT AND PROCESS DESIGN, AND POLICY DECISION MAKING: A CONFERENCE REPORT

    EPA Science Inventory

    On 24 September 2003, life cycle assessment (LCA) practitioners and decision makers gathered at the InLCA/LCM Conference in Seattle, Washington, USA (see http://www.lcacenter.org/InLCA-LCM03/index.html) to discuss the role of LCA in management, product design, process development...

  17. SHORTER MENSTRUAL CYCLES ASSOCIATED WITH CHLORINATION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Shorter Menstrual Cycles Associated with Chlorination by-Products in Drinking Water.
    Gayle Windham, Kirsten Waller, Meredith Anderson, Laura Fenster, Pauline Mendola, Shanna Swan. California Department of Health Services.

    In previous studies of tap water consumption we...

  18. CHLORINATION BY-PRODUCTS IN DRINKING WATER AND MENSTRUAL CYCLE FUNCTION

    EPA Science Inventory

    Chlorination by-Products in Drinking Water and Menstrual Cycle Function

    Gayle C. Windham1, Kirsten Waller2, Meredith Anderson2, Laura Fenster1, Pauline Mendola3, Shanna Swan4

    1California Department of Health Services, Division of Environmental and Occupational Disea...

  19. Topographic patterns of above- and below ground production and nitrogen cycling in alpine tundra

    SciTech Connect

    Fisk, M.C.; Schmidt, S.K.; Seastedt, T.R.

    1998-10-01

    Topography controls snowpack accumulation and hence growing-season length, soil water availability, and the distribution of plant communities in the Colorado Front Range alpine. Nutrient cycles in such an environment are likely to be regulated by interactions between topographically determined climate and plant species composition. The authors investigated variation in plant and soil components of internal N cycling across topographic gradients of dry, moist, and wet alpine tundra meadows at Niwot Ridge, Colorado. They expected that plant production and N cycling would increase from dry to wet alpine tundra meadows, but they hypothesized that variation in N turnover would span a proportionately greater range than productivity, because of feedbacks between plants and soil microbial processes that determine N availability. Plant production of foliage and roots increased over topographic sequences from 280 g{center_dot}m{sup {minus}2}{center_dot}yr{sup {minus}1} in dry meadows to 600 g{center_dot}m{sup {minus}2}{center_dot}yr{sup {minus}1} in wet meadows and was significantly correlated to soil moisture. Contrary to their expectation, plant N uptake for production increased to a lesser degree, from 3.9 g N{center_dot}m{sup {minus}2}{center_dot}yr{sup {minus}1} in dry meadows to 6.8 g N{center_dot}m{sup {minus}2}{center_dot}yr{sup {minus}1} in wet meadows. In all communities, the belowground component accounted for the majority of biomass, production, and N use for production.

  20. Marine fronts are important fishing areas for demersal species at the Argentine Sea (Southwest Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Alemany, Daniela; Acha, Eduardo M.; Iribarne, Oscar O.

    2014-03-01

    The high primary and secondary production associated with frontal systems attract a diversity of organisms due to high prey availability; this is why a strong relationship between fronts and pelagic fisheries has been shown worldwide. In the Argentine Sea, demersal resources are the most important, both in economical and in ecological sense; so we hypothesize that fronts are also preferred fishing areas for demersal resources. We evaluated the relationship between spatial distribution of fishing effort and oceanographic fronts, analyzing three of the most important frontal systems located in the Argentine Sea: the shelf-break front, the southern Patagonia front and the mid-shelf front. Individual vessel satellite monitoring system data (VMS; grouped by fleet type: ice-trawlers, freezer-trawlers and jigging fleet) were studied and fishing events were identified. Fishing events per area were used as a proxy of fishing effort and its spatial distribution by fleet type was visualized and analyzed with Geographic Information Systems. Oceanographic fronts were defined using polygons based on satellite chlorophyll amplitude values, and the percentage of fishing events within each polygon was calculated. Results showed a positive association between fronts and fishing activities of the different fleets, which suggests the aggregation of target species in these zones. The coupling of the freezer-trawler and jigging fleets (that operate on lower trophic level species; Macruronus magellanicus and Illex argentinus respectively) with fronts was higher than the ice-trawler fleet, targeting species of higher trophic level (Merluccius hubbsi). Marine fronts represent important fishing areas, even for demersal resources, as the distribution of fishing fleets and fishing effort are positively associated with frontal zones.

  1. Life cycle inventory for the production of germinated oil palm seeds at a selected seed production unit in Malaysia

    NASA Astrophysics Data System (ADS)

    Khairuddin, Nik Sasha Khatrina; Ismail, B. S.; Muhamad, Halimah; May, Choo Yuen

    2013-11-01

    The increasing global demand for edible oil has encouraged Malaysia to increase the areas under oil palm cultivation. The total demand for germinated oil palm seeds in the years 2009, 2010, 2011 and 2012 were 86.4, 76.5, 72.6 and 75.2 million, respectively. Production of germinated oil palm seeds is the first link in the palm oil supply chain. Therefore, good management practices at seed production stage is required to ensure only high quality germinated oil palm seeds are produced before sale to customers. Life cycle assessment (LCA) has been used as a tool to assess environmental impact of the processes throughout a product's lifespan and this approach is an important tool for assessing green house gas (GHG) emission. For this study, a gate-to-gate life cycle inventory (LCI) of a single germinated oil palm seed production unit was carried out. The functional unit used for this LCI was one germinated oil palm seed. To determine the environmental impact for the production of germinated oil palm seeds, information on the inputs were obtained. The inputs for the production of germinated oil palm seeds involved materials such as polyethylene bags, electricity, water, chemicals and fungicides. For this study, the system boundary involved seed germination process and management of germinated oil palm seeds. It was found that the amount of input such as materials and energy used in the production of germinated oil palm seeds was very minimal.

  2. Diel cycles in calcite production and dissolution in a eutrophic basin

    SciTech Connect

    Cicerone, D.S.; Stewart, A.J.; Roh, Y.

    1999-10-01

    Calcite production is understood largely as a longer-term phenomenon (e.g., seasonal whitings) that can occur in hardwater lakes, and is significant ecologically because it can slow the rate of eutrophication by reducing, through adsorption, the availability of nutrients to primary producers. In this study the authors show that rapid changes in concentration of dissolved CO{sub 2} by photosynthesis and respiration within a eutrophic basin generated strong day-to-night cycles in calcite production and dissolution. Diel cycles in calcite production and dissolution were large enough that they could drive secondary diel cycles in the availability of metals that strongly sorb to the surfaces of calcite particles. They explored the possibility of the secondary diel cycling of metals by intensive 7-d in situ monitoring of water-quality conditions in a shallow, eutrophic spill-control basin near an industrial facility in eastern Tennessee; inspecting data from a 7-year record of water-quality parameters for this basin; analyzing physicochemical characteristics and mineralogic composition of sediments in the basin; and conducting laboratory experiments to characterize the interaction of calcite with Cd, under solid-liquid nonequilibrium conditions. The authors found that the basin accumulated and stored calcite. In situ monitoring showed that calcite was produced during daylight, and tended to dissolve again at night; the calcite production and dissolution processes seemed to be modulated by dissolved-phase CO{sub 2} dynamics, in concert with large diel fluctuations in pCa, pH, and Po{sub 2}. Laboratory experiments showed a rapid interaction ({lt}6 h) of Cd with calcite, in response to dissolved CO{sub 2} changes. Thus, concentrations of dissolved Cd can vary over daily cycles, mediated by diel changes in calcite production and dissolution. Thermodynamic considerations suggest that other metals, such as Zn, Sr, Ni, and Ba, may demonstrate this behavior as well.

  3. Pull-in urea cycle for the production of fumaric acid in Escherichia coli.

    PubMed

    Zhang, Ting; Wang, Zening; Deng, Li; Tan, Tianwei; Wang, Fang; Yan, Yajun

    2015-06-01

    Fumaric acid (FA) is an important raw material in the chemical and pharmaceutical industries. In this work, Escherichia coli was metabolically engineered for the production of FA. The fumA, fumB, fumC, and frdABCD genes were deleted to cut off the downstream pathway of FA. In addition, the iclR and arcA genes were also deleted to activate the glyoxylate shunt and to reinforce the oxidative Krebs cycle. To increase the FA yield, this base strain was further engineered to be pulled in the urea cycle by overexpressing the native carAB, argI, and heterologous rocF genes. The metabolites and the proteins of the Krebs cycle and the urea cycle were analyzed to confirm that the induced urea cycle improved the FA accumulation. With the induced urea cycle, the resulting strain ABCDIA-RAC was able to produce 11.38 mmol/L of FA from 83.33 mmol/L of glucose in a flask culture during 24 h of incubation.

  4. Methodological issues in life cycle assessment of mixed-culture polyhydroxyalkanoate production utilising waste as feedstock.

    PubMed

    Heimersson, Sara; Morgan-Sagastume, Fernando; Peters, Gregory M; Werker, Alan; Svanström, Magdalena

    2014-06-25

    Assessing the environmental performance of emerging technologies using life cycle assessment (LCA) can be challenging due to a lack of data in relation to technologies, application areas or other life cycle considerations, or a lack of LCA methodology that address the specific concerns. Nevertheless, LCA can be a valuable tool in the environmental optimisation in the technology development phase. One emerging technology is the mixed-culture production of polyhydroxyalkanoates (PHAs). PHA production by pure microbial cultures has been developed and assessed in several LCAs during the previous decade. Recent developments within mixed-culture PHA production call for environmental assessment to guide in technology development. Mixed-culture PHA production can use the organic content in wastewater as a feedstock; the production may then be integrated with wastewater treatment (WWT) processes. This means that mixed-culture PHA is produced as a by-product from services in the WWT. This article explores different methodological challenges for LCA of mixed-culture PHA production using organic material in wastewater as feedstock. LCAs of both pure- and mixed-culture PHA production were reviewed. Challenges, similarities and differences when assessing PHA production by mixed- or pure-cultures were identified and the resulting implications for methodological choices in LCA were evaluated and illustrated, using a case study with mixed- and pure-culture PHA model production systems, based on literature data. Environmental impacts of processes producing multiple products or services need to be allocated between the different products or services. Such situations occur both in feedstock production and when the studied system is providing multiple functions. The selection of allocation method is shown to determine the LCA results. The type of data used, for electricity in the energy system, is shown to be important for the results, which indicates, a strong regional dependency of

  5. Krebs cycle intermediates modulate thiobarbituric acid reactive species (TBARS) production in rat brain in vitro.

    PubMed

    Puntel, Robson L; Nogueira, Cristina W; Rocha, João B T

    2005-02-01

    The aim of this study was to investigate the effect of Krebs cycle intermediates on basal and quinolinic acid (QA)- or iron-induced TBARS production in brain membranes. Oxaloacetate, citrate, succinate and malate reduced significantly the basal and QA-induced TBARS production. The potency for basal TBARS inhibition was in the order (IC50 is given in parenthesis as mM) citrate (0.37) > oxaloacetate (1.33) = succinate (1.91) > > malate (12.74). alpha-Ketoglutarate caused an increase in TBARS production without modifying the QA-induced TBARS production. Cyanide (CN-) did not modify the basal or QA-induced TBARS production; however, CN- abolished the antioxidant effects of succinate. QA-induced TBARS production was enhanced by iron ions, and abolished by desferrioxamine (DFO). The intermediates used in this study, except for alpha-ketoglutarate, prevented iron-induced TBARS production. Oxaloacetate, citrate, alpha-ketoglutarate and malate, but no succinate and QA, exhibited significantly iron-chelating properties. Only alpha-ketoglutarate and oxaloacetate protected against hydrogen peroxide-induced deoxyribose degradation, while succinate and malate showed a modest effect against Fe2+/H2O2-induced deoxyribose degradation. Using heat-treated preparations citrate, malate and oxaloacetate protected against basal or QA-induced TBARS production, whereas alpha-ketoglutarate induced TBARS production. Succinate did not offer protection against basal or QA-induced TBARS production. These results suggest that oxaloacetate, malate, succinate, and citrate are effective antioxidants against basal and iron or QA-induced TBARS production, while alpha-ketoglutarate stimulates TBARS production. The mechanism through which Krebs cycle intermediates offer protection against TBARS production is distinct depending on the intermediate used. Thus, under pathological conditions such as ischemia, where citrate concentrations vary it can assume an important role as a modulator of oxidative

  6. Updated Life-Cycle Assessment of Aluminum Production and Semi-fabrication for the GREET Model

    SciTech Connect

    Dai, Qiang; Kelly, Jarod C.; Burnham, Andrew; Elgowainy, Amgad

    2015-09-01

    This report serves as an update for the life-cycle analysis (LCA) of aluminum production based on the most recent data representing the state-of-the-art of the industry in North America. The 2013 Aluminum Association (AA) LCA report on the environmental footprint of semifinished aluminum products in North America provides the basis for the update (The Aluminum Association, 2013). The scope of this study covers primary aluminum production, secondary aluminum production, as well as aluminum semi-fabrication processes including hot rolling, cold rolling, extrusion and shape casting. This report focuses on energy consumptions, material inputs and criteria air pollutant emissions for each process from the cradle-to-gate of aluminum, which starts from bauxite extraction, and ends with manufacturing of semi-fabricated aluminum products. The life-cycle inventory (LCI) tables compiled are to be incorporated into the vehicle cycle model of Argonne National Laboratory’s Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) Model for the release of its 2015 version.

  7. Status of the DOE (STOR)-sponsored national program on hydrogen production from water via thermochemical cycles

    NASA Technical Reports Server (NTRS)

    Baker, C. E.

    1977-01-01

    The program structure is presented. The activities of the thermochemical cycles program are grouped according to the following categories: (1) specific cycle development, (2) support research and technology, (3) cycle evaluation. Specific objectives and status of on-going activities are discussed. Chemical reaction series for the production of hydrogen are presented. Efficiency and economic evaluations are also discussed.

  8. Life cycle assessment of the production of ethanol from eastern redcedar.

    PubMed

    Olukoya, Ife A; Ramachandriya, Karthikeyan D; Wilkins, Mark R; Aichele, Clint P

    2014-12-01

    This life cycle assessment (LCA) evaluates the environmental impacts of an ethanol production system using eastern redcedar (Juniperus virginiana L.) as the feedstock. Aspen Plus® was used to model the acid bisulfite pretreatment, enzymatic hydrolysis, fermentation, and distillation steps. A cradle-to-gate LCA was conducted to evaluate the environmental impacts from cutting the trees to the production of anhydrous ethanol. The environmental impacts of the redcedar ethanol process were compared to those from the production of corn ethanol. Inventory data for the system were collected and used to calculate a life cycle impact assessment (LCIA) using the IMPACT 2002+ and BEES+ framework in SimaPro 8.0.0. Four impact categories were evaluated: land occupation, water use, greenhouse gas (GHG) emissions, and non-renewable energy use. Results indicate that acid bisulfite pretreatment contributed to 65% of GHG emissions, 81% of non-renewable energy use, and 77% of water use of the overall process.

  9. Increased production of cellulase of Trichoderma sp. By pH cycling and temperature profiling

    SciTech Connect

    Mukhopadhyay, S.N.; Malik, R.K.

    1980-01-01

    Cultivation of Trichoderma reesei QM 9414 on 3% cellulose medium (C/N ratio equal to 8.5) produced 4.5 IU/mL cellulase in 180 h at a cell growth of 8.0 g/L. It corresponded to an average cellulase productivity of 25.0 IU/L/h. In the same medium 9.5 g/L cell mass, 6.2 IU/mL cellulase, and 38.75 IU/L/h cellulase productivity could be obtained using pH cycling during cultivation. Cell mass, cellulase yield, and productivity were further increased to 10,0 g/L, 7.2 IU/mL, and 44.0 IU/L/h (4.5 IU/g cell/h), respectively, by simultaneous pH cycling and temperature profiling. Results are described.

  10. Life cycle assessment of the production of ethanol from eastern redcedar.

    PubMed

    Olukoya, Ife A; Ramachandriya, Karthikeyan D; Wilkins, Mark R; Aichele, Clint P

    2014-12-01

    This life cycle assessment (LCA) evaluates the environmental impacts of an ethanol production system using eastern redcedar (Juniperus virginiana L.) as the feedstock. Aspen Plus® was used to model the acid bisulfite pretreatment, enzymatic hydrolysis, fermentation, and distillation steps. A cradle-to-gate LCA was conducted to evaluate the environmental impacts from cutting the trees to the production of anhydrous ethanol. The environmental impacts of the redcedar ethanol process were compared to those from the production of corn ethanol. Inventory data for the system were collected and used to calculate a life cycle impact assessment (LCIA) using the IMPACT 2002+ and BEES+ framework in SimaPro 8.0.0. Four impact categories were evaluated: land occupation, water use, greenhouse gas (GHG) emissions, and non-renewable energy use. Results indicate that acid bisulfite pretreatment contributed to 65% of GHG emissions, 81% of non-renewable energy use, and 77% of water use of the overall process. PMID:25305654

  11. Life cycle assessment of nuclear-based hydrogen production via thermochemical water splitting using a copper-chlorine (Cu-Cl) cycle

    NASA Astrophysics Data System (ADS)

    Ozbilen, Ahmet Ziyaettin

    The energy carrier hydrogen is expected to solve some energy challenges. Since its oxidation does not emit greenhouse gases (GHGs), its use does not contribute to climate change, provided that it is derived from clean energy sources. Thermochemical water splitting using a Cu-Cl cycle, linked with a nuclear super-critical water cooled reactor (SCWR), which is being considered as a Generation IV nuclear reactor, is a promising option for hydrogen production. In this thesis, a comparative environmental study is reported of the three-, four- and five-step Cu-Cl thermochemical water splitting cycles with various other hydrogen production methods. The investigation uses life cycle assessment (LCA), which is an analytical tool to identify and quantify environmentally critical phases during the life cycle of a system or a product and/or to evaluate and decrease the overall environmental impact of the system or product. The LCA results for the hydrogen production processes indicate that the four-step Cu-Cl cycle has lower environmental impacts than the three- and five-step Cu-Cl cycles due to its lower thermal energy requirement. Parametric studies show that acidification potentials (APs) and global warming potentials (GWPs) for the four-step Cu-Cl cycle can be reduced from 0.0031 to 0.0028 kg SO2-eq and from 0.63 to 0.55 kg CO2-eq, respectively, if the lifetime of the system increases from 10 to 100 years. Moreover, the comparative study shows that the nuclear-based S-I and the four-step Cu-Cl cycles are the most environmentally benign hydrogen production methods in terms of AP and GWP. GWPs of the S-I and the four-step Cu-Cl cycles are 0.412 and 0.559 kg CO2-eq for reference case which has a lifetime of 60 years. Also, the corresponding APs of these cycles are 0.00241 and 0.00284 kg SO2-eq. It is also found that an increase in hydrogen plant efficiency from 0.36 to 0.65 decreases the GWP from 0.902 to 0.412 kg CO 2-eq and the AP from 0.00459 to 0.00209 kg SO2-eq for the

  12. Comparative life cycle assessment and financial analysis of mixed culture polyhydroxyalkanoate production.

    PubMed

    Gurieff, Nicholas; Lant, Paul

    2007-12-01

    A life cycle assessment and financial analysis of mixed culture PHA (PHA(MC)) and biogas production was undertaken based on treating an industrial wastewater. Internal rate of return (IRR) and non-renewable CO(2)eq emissions were used to quantify financial viability and environmental impact. PHA(MC) was preferable to biogas production for treating the specified industrial effluent. PHA(MC) was also financially attractive in comparison to pure culture PHA production. Both PHA production processes had similar environmental impacts that were significantly lower than HDPE production. A large potential for optimisation exists for the PHA(MC) process as financial and environmental costs were primarily due to energy use for downstream processing. Under the conditions used in this work PHA(MC) was shown to be a viable biopolymer production process and an effective industrial wastewater treatment technology. This is the first study of its kind and provides valuable insight into the PHA(MC) process. PMID:17632000

  13. Life cycle assessment of biofuel production from brown seaweed in Nordic conditions.

    PubMed

    Alvarado-Morales, Merlin; Boldrin, Alessio; Karakashev, Dimitar B; Holdt, Susan L; Angelidaki, Irini; Astrup, Thomas

    2013-02-01

    The use of algae for biofuel production is expected to play an important role in securing energy supply in the next decades. A consequential life cycle assessment (LCA) and an energy analysis of seaweed-based biofuel production were carried out in Nordic conditions to document and improve the sustainability of the process. Two scenarios were analyzed for the brown seaweed (Laminaria digitata), namely, biogas production (scenario 1) and bioethanol+biogas production (scenario 2). Potential environmental impact categories under investigation were Global Warming, Acidification and Terrestrial Eutrophication. The production of seaweed was identified to be the most energy intensive step. Scenario 1 showed better performance compared to scenario 2 for all impact categories, partly because of the energy intensive bioethanol separation process and the consequently lower overall efficiency of the system. For improved environmental performance, focus should be on optimization of seaweed production, bioethanol distillation, and management of digestate on land.

  14. Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

    USGS Publications Warehouse

    Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

  15. Trail pheromone disruption of Argentine ant trail formation and foraging.

    PubMed

    Suckling, David Maxwell; Peck, Robert W; Stringer, Lloyd D; Snook, Kirsten; Banko, Paul C

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2–3 m s−1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. PMID:20077128

  16. Reversal of the β-oxidation cycle in Saccharomyces cerevisiae for production of fuels and chemicals.

    PubMed

    Lian, Jiazhang; Zhao, Huimin

    2015-03-20

    Functionally reversing the β-oxidation cycle represents an efficient and versatile strategy for synthesis of a wide variety of fuels and chemicals. However, due to the compartmentalization of cellular metabolisms, reversing the β-oxidation cycle in eukaryotic systems remains elusive. Here, we report the first successful reversal of the β-oxidation cycle in Saccharomyces cerevisiae, an important cell factory for large-scale production of fuels and chemicals. After extensive gene cloning and enzyme activity assays, a reversed β-oxidation pathway was functionally constructed in the yeast cytosol, which led to the synthesis of n-butanol, medium-chain fatty acids (MCFAs), and medium-chain fatty acid ethyl esters (MCFAEEs). The resultant recombinant strain provides a new broadly applicable platform for synthesis of fuels and chemicals in S. cerevisiae.

  17. Biodiesel production in a semiarid environment: a life cycle assessment approach.

    PubMed

    Biswas, Wahidul K; Barton, Louise; Carter, Daniel

    2011-04-01

    While the use of biodiesel appears to be a promising alternative to petroleum fuel, the replacement of fossil fuel by biofuel may not bring about the intended climate cooling because of the increased soil N2O emissions due to N-fertilizer applications. Using a life cycle assessment approach, we assessed the influence of soil nitrous oxide (N2O) emissions on the life cycle global warming potential of the production and combustion of biodiesel from canola oil produced in a semiarid climate. Utilizing locally measured soil N2O emissions, rather than the Intergovernmental Panel on Climate Change (IPCC) default values, decreased greenhouse gas (GHG) emissions from the production and combustion of 1 GJ biodiesel from 63 to 37 carbon dioxide equivalents (CO2-e)/GJ. GHG were 1.1 to 2.1 times lower than those from petroleum or petroleum-based diesel depending on which soil N2O emission factors were included in the analysis. The advantages of utilizing biodiesel rapidly declined when blended with petroleum diesel. Mitigation strategies that decrease emissions from the production and application of N fertilizers may further decrease the life cycle GHG emissions in the production and combustion of biodiesel. PMID:21381655

  18. Development of a Life Cycle Inventory of Water Consumption Associated with the Production of Transportation Fuels

    SciTech Connect

    Lampert, David J.; Cai, Hao; Wang, Zhichao; Keisman, Jennifer; Wu, May; Han, Jeongwoo; Dunn, Jennifer; Sullivan, John L.; Elgowainy, Amgad; Wang, Michael; Keisman, Jennifer

    2015-10-01

    The production of all forms of energy consumes water. To meet increased energy demands, it is essential to quantify the amount of water consumed in the production of different forms of energy. By analyzing the water consumed in different technologies, it is possible to identify areas for improvement in water conservation and reduce water stress in energy-producing regions. The transportation sector is a major consumer of energy in the United States. Because of the relationships between water and energy, the sustainability of transportation is tied to management of water resources. Assessment of water consumption throughout the life cycle of a fuel is necessary to understand its water resource implications. To perform a comparative life cycle assessment of transportation fuels, it is necessary first to develop an inventory of the water consumed in each process in each production supply chain. The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model is an analytical tool that can used to estimate the full life-cycle environmental impacts of various transportation fuel pathways from wells to wheels. GREET is currently being expanded to include water consumption as a sustainability metric. The purpose of this report was to document data sources and methodologies to estimate water consumption factors (WCF) for the various transportation fuel pathways in GREET. WCFs reflect the quantity of freshwater directly consumed per unit production for various production processes in GREET. These factors do not include consumption of precipitation or low-quality water (e.g., seawater) and reflect only water that is consumed (i.e., not returned to the source from which it was withdrawn). The data in the report can be combined with GREET to compare the life cycle water consumption for different transportation fuels.

  19. Comparative life-cycle assessments for biomass-to-ethanol production from different regional feedstocks.

    PubMed

    Kemppainen, Amber J; Shonnard, David R

    2005-01-01

    This study compares life-cycle (cradle-to-gate) energy consumption and environmental impacts for producing ethanol via fermentation-based processes starting with two lignocellulosic feedstocks: virgin timber resources or recycled newsprint from an urban area. The life-cycle assessment in this study employed a novel combination of computer-aided tools. These tools include fermentation process simulation coupled with an impact assessment software tool for the manufacturing process life-cycle stage impacts. The process simulation file was provided by the National Renewable Energy Laboratory (NREL) and was modified slightly to accommodate these different feedstocks. For the premanufacturing process life-cycle stage impacts, such as the fuels and process chemicals used, transportation, and some preparatory steps (wood chipping, etc.), a life-cycle inventory database (the Boustead Model) coupled with an impact assessment software tool were used (the Environmental Fate and Risk Assessment Tool). The Newsprint process has a slightly lower overall composite environmental index (created from eight impact categories) compared to the Timber process. However, the Timber process consumes less electricity, produces fewer emissions in total, and has less of a human health impact. The amount of life-cycle fossil energy required to produce ethanol is 14% of the energy content of the product, making the overall efficiency 86%. Process improvement strategies were evaluated for both feedstock processes, including recycle of reactor vent air and heat integration. Heat integration has the greatest potential to reduce fossil-derived energy consumption, to an extent that fossil-derived energy over the life cycle is actually saved per unit of ethanol produced. These energy efficiency values are superior to those observed in conventional fossil-based transportation fuels. PMID:16080686

  20. Comparative life-cycle assessments for biomass-to-ethanol production from different regional feedstocks.

    PubMed

    Kemppainen, Amber J; Shonnard, David R

    2005-01-01

    This study compares life-cycle (cradle-to-gate) energy consumption and environmental impacts for producing ethanol via fermentation-based processes starting with two lignocellulosic feedstocks: virgin timber resources or recycled newsprint from an urban area. The life-cycle assessment in this study employed a novel combination of computer-aided tools. These tools include fermentation process simulation coupled with an impact assessment software tool for the manufacturing process life-cycle stage impacts. The process simulation file was provided by the National Renewable Energy Laboratory (NREL) and was modified slightly to accommodate these different feedstocks. For the premanufacturing process life-cycle stage impacts, such as the fuels and process chemicals used, transportation, and some preparatory steps (wood chipping, etc.), a life-cycle inventory database (the Boustead Model) coupled with an impact assessment software tool were used (the Environmental Fate and Risk Assessment Tool). The Newsprint process has a slightly lower overall composite environmental index (created from eight impact categories) compared to the Timber process. However, the Timber process consumes less electricity, produces fewer emissions in total, and has less of a human health impact. The amount of life-cycle fossil energy required to produce ethanol is 14% of the energy content of the product, making the overall efficiency 86%. Process improvement strategies were evaluated for both feedstock processes, including recycle of reactor vent air and heat integration. Heat integration has the greatest potential to reduce fossil-derived energy consumption, to an extent that fossil-derived energy over the life cycle is actually saved per unit of ethanol produced. These energy efficiency values are superior to those observed in conventional fossil-based transportation fuels.

  1. Solar Metal Sulfate-Ammonia Based Thermochemical Water Splitting Cycle for Hydrogen Production

    NASA Technical Reports Server (NTRS)

    Huang, Cunping (Inventor); T-Raissi, Ali (Inventor); Muradov, Nazim (Inventor)

    2014-01-01

    Two classes of hybrid/thermochemical water splitting processes for the production of hydrogen and oxygen have been proposed based on (1) metal sulfate-ammonia cycles (2) metal pyrosulfate-ammonia cycles. Methods and systems for a metal sulfate MSO.sub.4--NH3 cycle for producing H2 and O2 from a closed system including feeding an aqueous (NH3)(4)SO3 solution into a photoctalytic reactor to oxidize the aqueous (NH3)(4)SO3 into aqueous (NH3)(2)SO4 and reduce water to hydrogen, mixing the resulting aqueous (NH3)(2)SO4 with metal oxide (e.g. ZnO) to form a slurry, heating the slurry of aqueous (NH4)(2)SO4 and ZnO(s) in the low temperature reactor to produce a gaseous mixture of NH3 and H2O and solid ZnSO4(s), heating solid ZnSO4 at a high temperature reactor to produce a gaseous mixture of SO2 and O2 and solid product ZnO, mixing the gaseous mixture of SO2 and O2 with an NH3 and H2O stream in an absorber to form aqueous (NH4)(2)SO3 solution and separate O2 for aqueous solution, recycling the resultant solution back to the photoreactor and sending ZnO to mix with aqueous (NH4)(2)SO4 solution to close the water splitting cycle wherein gaseous H2 and O2 are the only products output from the closed ZnSO4--NH3 cycle.

  2. Products and stability of phosphate reactions with lead under freeze-thaw cycling in simple systems.

    PubMed

    Hafsteinsdóttir, Erla G; White, Duanne A; Gore, Damian B; Stark, Scott C

    2011-12-01

    Orthophosphate fixation of metal contaminated soils in environments that undergo freeze-thaw cycles is understudied. Freeze-thaw cycling potentially influences the reaction rate, mineral chemical stability and physical breakdown of particles during fixation. This study determines what products form when phosphate (triple superphosphate [Ca(H(2)PO(4))(2)] or sodium phosphate [Na(3)PO(4)]) reacts with lead (PbSO(4) or PbCl(2)) in simple chemical systems in vitro, and assesses potential changes in formation during freeze-thaw cycles. Systems were subjected to multiple freeze-thaw cycles from +10 °C to -20 °C and then analysed by X-ray diffractometry. Pyromorphite formed in all systems and was stable over multiple freeze-thaw cycles. Low temperature lead orthophosphate reaction efficiency varied according to both phosphate and lead source; the most time-efficient pyromorphite formation was observed when PbSO(4) and Na(3)PO(4) were present together. These findings have implications for the manner in which metal contaminated materials in freezing ground can be treated with phosphate. PMID:21907472

  3. Life cycle assessment of corn-based ethanol production in Argentina.

    PubMed

    Pieragostini, Carla; Aguirre, Pío; Mussati, Miguel C

    2014-02-15

    The promotion of biofuels as energy for transportation in the world is mainly driven by the perspective of oil depletion, the concerns about energy security and global warming. In Argentina, the legislation has imposed the use of biofuels in blend with fossil fuels (5 to 10%) in the transport sector. The aim of this paper is to assess the environmental impact of corn-based ethanol production in the province of Santa Fe in Argentina based on the life cycle assessment methodology. The studied system includes from raw materials production to anhydrous ethanol production using dry milling technology. The system is divided into two subsystems: agricultural system and refinery system. The treatment of stillage is considered as well as the use of co-products (distiller's dried grains with solubles), but the use and/or application of the produced biofuel is not analyzed: a cradle-to-gate analysis is presented. As functional unit, 1MJ of anhydrous ethanol at biorefinery is chosen. Two life cycle impact assessment methods are selected to perform the study: Eco-indicator 99 and ReCiPe. SimaPro is the life cycle assessment software used. The influence of the perspectives on the model is analyzed by sensitivity analysis for both methods. The two selected methods identify the same relevant processes. The use of fertilizers and resources, seeds production, harvesting process, corn drying, and phosphorus fertilizers and acetamide-anillide-compounds production are the most relevant processes in agricultural system. For refinery system, corn production, supplied heat and burned natural gas result in the higher contributions. The use of distiller's dried grains with solubles has an important positive environmental impact. PMID:24295743

  4. A Life-Cycle Assessment of Biofuels: Tracing Energy and Carbon through a Fuel-Production System

    ERIC Educational Resources Information Center

    Krauskopf, Sara

    2010-01-01

    A life-cycle assessment (LCA) is a tool used by engineers to make measurements of net energy, greenhouse gas production, water consumption, and other items of concern. This article describes an activity designed to walk students through the qualitative part of an LCA. It asks them to consider the life-cycle costs of ethanol production, in terms of…

  5. Effects of co-products on the life-cycle impacts of microalgal biodiesel.

    PubMed

    Soratana, Kullapa; Barr, William J; Landis, Amy E

    2014-05-01

    Microalgal biodiesel production has been investigated for decades, yet it is not commercially available. Part of the problem is that the production process is energy and chemical intensive due, in part, to the high portion of microalgal biomass left as residues. This study investigated cradle-to-gate life-cycle environmental impacts from six different scenarios of microalgal biodiesel and its co-products. Ozone depletion, global warming, photochemical smog formation, acidification and eutrophication potentials were assessed using the Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI). Monte Carlo Analysis was conducted to investigate the processes with major contribution in each impact category. The market opportunity for each co-product was examined based on supply, demand and prices of the products that could potentially be substituted by the co-products. The results indicated that the scenario with the least life-cycle environmental impacts in all the five impact categories with the highest net energy ratio was the scenario utilizing a multitude of co-products including bioethanol from lipid-extracted microalgae (LEA), biomethane (to produce electricity and heat) from simultaneous saccharification-fermentation (SSF) residues, land-applied material from SSF residue anaerobic digestion (AD) solid digestate, recycling nutrients from SSF residue AD liquid digestate and CO2 recovered from SSF process contributed. Decreasing the energy consumption of the centrifuge in the land-applied material production process and increasing the lipid content of microalgae can reduce environmental footprints of the co-products. The same scenario also had the highest total income indicating their potential as co-products in the market.

  6. Effects of co-products on the life-cycle impacts of microalgal biodiesel.

    PubMed

    Soratana, Kullapa; Barr, William J; Landis, Amy E

    2014-05-01

    Microalgal biodiesel production has been investigated for decades, yet it is not commercially available. Part of the problem is that the production process is energy and chemical intensive due, in part, to the high portion of microalgal biomass left as residues. This study investigated cradle-to-gate life-cycle environmental impacts from six different scenarios of microalgal biodiesel and its co-products. Ozone depletion, global warming, photochemical smog formation, acidification and eutrophication potentials were assessed using the Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI). Monte Carlo Analysis was conducted to investigate the processes with major contribution in each impact category. The market opportunity for each co-product was examined based on supply, demand and prices of the products that could potentially be substituted by the co-products. The results indicated that the scenario with the least life-cycle environmental impacts in all the five impact categories with the highest net energy ratio was the scenario utilizing a multitude of co-products including bioethanol from lipid-extracted microalgae (LEA), biomethane (to produce electricity and heat) from simultaneous saccharification-fermentation (SSF) residues, land-applied material from SSF residue anaerobic digestion (AD) solid digestate, recycling nutrients from SSF residue AD liquid digestate and CO2 recovered from SSF process contributed. Decreasing the energy consumption of the centrifuge in the land-applied material production process and increasing the lipid content of microalgae can reduce environmental footprints of the co-products. The same scenario also had the highest total income indicating their potential as co-products in the market. PMID:24650529

  7. The Conceptual Design of an Integrated Nuclearhydrogen Production Plant Using the Sulfur Cycle Water Decomposition System

    NASA Technical Reports Server (NTRS)

    Farbman, G. H.

    1976-01-01

    A hydrogen production plant was designed based on a hybrid electrolytic-thermochemical process for decomposing water. The sulfur cycle water decomposition system is driven by a very high temperature nuclear reactor that provides 1,283 K helium working gas. The plant is sized to approximately ten million standard cubic meters per day of electrolytically pure hydrogen and has an overall thermal efficiently of 45.2 percent. The economics of the plant were evaluated using ground rules which include a 1974 cost basis without escalation, financing structure and other economic factors. Taking into account capital, operation, maintenance and nuclear fuel cycle costs, the cost of product hydrogen was calculated at $5.96/std cu m for utility financing. These values are significantly lower than hydrogen costs from conventional water electrolysis plants and competitive with hydrogen from coal gasification plants.

  8. Life-cycle energy efficiency and environmental impacts of bioethanol production from sweet potato.

    PubMed

    Wang, Mingxin; Shi, Yu; Xia, Xunfeng; Li, Dinglong; Chen, Qun

    2013-04-01

    Life-cycle assessment (LCA) was used to evaluate the energy efficiency and environmental impacts of sweet potato-based bioethanol production. The scope covered all stages in the life cycle of bioethanol production, including the cultivation and treatment, transport, as well as bioethanol conversion of sweet potato. Results show that the net energy ratio of sweet potato-based bioethanol is 1.48 and the net energy gain is 6.55 MJ/L. Eutrophication is identified as the most significant environmental impact category, followed by acidification, global warming, human toxicity, and photochemical oxidation. Sensitivity analysis reveals that steam consumption during bioethanol conversion exerts the most effect on the results, followed by sweet potato yields and fertilizers input. It is suggested that substituting coal with cleaner energy for steam generation in bioethanol conversion stage and promotion of better management practices in sweet potato cultivation stage could lead to a significant improvement of energy and environmental performance.

  9. Cycle expansion for the Lyapunov exponent of a product of random matrices.

    PubMed

    Mainieri, Ronnie

    1992-01-01

    Using cycle expansion for the thermodynamic zeta function, a formula is derived for the Lyapunov exponent of a product of random hyperbolic matrices chosen from a discrete set. This allows for an accurate numerical solution of the Ising model in one dimension with quenched disorder. The formula is compared with weak disorder expansions and with the microcanonical approximation and shown to apply to matrices with degenerate eigenvalues.

  10. Life cycle impact assessment of ammonia production in Algeria: A comparison with previous studies

    SciTech Connect

    Makhlouf, Ali Serradj, Tayeb; Cheniti, Hamza

    2015-01-15

    In this paper, a Life Cycle Analysis (LCA) from “cradle to gate” of one anhydrous ton of ammonia with a purity of 99% was achieved. Particularly, the energy and environmental performance of the product (ammonia) were evaluated. The eco-profile of the product and the share of each stage of the Life Cycle on the whole environmental impacts have been evaluated. The flows of material and energy for each phase of the life cycle were counted and the associated environmental problems were identified. Evaluation of the impact was achieved using GEMIS 4.7 software. The primary data collection was executed at the production installations located in Algeria (Annaba locality). The analysis was conducted according to the LCA standards ISO 14040 series. The results show that Cumulative Energy Requirement (CER) is of 51.945 × 10{sup 3} MJ/t of ammonia, which is higher than the global average. Global Warming Potential (GWP) is of 1.44 t CO{sub 2} eq/t of ammonia; this value is lower than the world average. Tropospheric ozone precursor and Acidification are also studied in this article, their values are: 549.3 × 10{sup −6} t NMVOC eq and 259.3 × 10{sup −6} t SO{sub 2} eq respectively.

  11. Bioinformatics for the synthetic biology of natural products: integrating across the Design–Build–Test cycle

    PubMed Central

    Currin, Andrew; Jervis, Adrian J.; Rattray, Nicholas J. W.; Swainston, Neil; Yan, Cunyu; Breitling, Rainer

    2016-01-01

    Covering: 2000 to 2016 Progress in synthetic biology is enabled by powerful bioinformatics tools allowing the integration of the design, build and test stages of the biological engineering cycle. In this review we illustrate how this integration can be achieved, with a particular focus on natural products discovery and production. Bioinformatics tools for the DESIGN and BUILD stages include tools for the selection, synthesis, assembly and optimization of parts (enzymes and regulatory elements), devices (pathways) and systems (chassis). TEST tools include those for screening, identification and quantification of metabolites for rapid prototyping. The main advantages and limitations of these tools as well as their interoperability capabilities are highlighted. PMID:27185383

  12. Consumption-weighted life cycle assessment of a consumer electronic product community.

    PubMed

    Ryen, Erinn G; Babbitt, Callie W; Williams, Eric

    2015-02-17

    A new approach for quantifying the net environmental impact of a "community" of interrelated products is demonstrated for consumer electronics owned by an average U.S. household over a 15-year period (1992-2007). This consumption-weighted life cycle assessment (LCA) methodology accounts for both product consumption (number of products per household) and impact (cumulative energy demand (MJ) and greenhouse gas emissions (MT CO2 eq) per product), analyzed using a hybrid LCA framework. Despite efficiency improvements in individual devices from 1992 to 2007, the net impact of the entire product community increased, due primarily to increasing ownership and usage. The net energy impact for the product community is significant, nearly 30% of the average gasoline use in a U.S. passenger vehicle in 2007. The analysis points to a large contribution by legacy products (cathode ray tube televisions and desktop computers), due to historically high consumption rates, although impacts are beginning to shift to smaller mobile devices. This method is also applied to evaluate prospective intervention strategies, indicating that environmental impact can be reduced by strategies such as lifespan extension or energy efficiency, but only when applied to all products owned, or by transforming consumption trends toward fewer, highly multifunctional products.

  13. Life cycle water footprint of hydrogenation-derived renewable diesel production from lignocellulosic biomass.

    PubMed

    Wong, Alain; Zhang, Hao; Kumar, Amit

    2016-10-01

    The conversion of lignocellulosic biomass to biofuel requires water. This study is focused on the production of hydrogenation-derived renewable diesel (HDRD) from lignocellulosic biomass. Although there has been considerable focus on the assessment of greenhouse gas (GHG) emissions, there is limited work on the assessment of the life cycle water footprint of HDRD production. This paper presents a life cycle water consumption study on lignocellulosic biomass to HDRD via pyrolysis and hydrothermal liquefaction (HTL) processes. The results of this study show that whole tree (i.e., tree chips) biomass has water requirements of 497.79 L/MJ HDRD and 376.16 L/MJ HDRD for production through fast pyrolysis and the HTL process, respectively. Forest residues (i.e., chips from branches and tops generated during logging operations) have water requirements of 338.58 L/MJ HDRD and 255.85 L/MJ HDRD for production through fast pyrolysis and the HTL process, respectively. Agricultural residues (i.e., straw from wheat, oats, and barley), which are more water efficient, have water requirements of 83.7 L/MJ HDRD and 59.1 L/MJ HDRD through fast pyrolysis and the HTL process, respectively. Differences in water use between feedstocks and conversion processes indicate that the choices of biomass feedstock and conversion pathway water efficiency are crucial factors affecting water use efficiency of HDRD production. PMID:27379729

  14. Life cycle water footprint of hydrogenation-derived renewable diesel production from lignocellulosic biomass.

    PubMed

    Wong, Alain; Zhang, Hao; Kumar, Amit

    2016-10-01

    The conversion of lignocellulosic biomass to biofuel requires water. This study is focused on the production of hydrogenation-derived renewable diesel (HDRD) from lignocellulosic biomass. Although there has been considerable focus on the assessment of greenhouse gas (GHG) emissions, there is limited work on the assessment of the life cycle water footprint of HDRD production. This paper presents a life cycle water consumption study on lignocellulosic biomass to HDRD via pyrolysis and hydrothermal liquefaction (HTL) processes. The results of this study show that whole tree (i.e., tree chips) biomass has water requirements of 497.79 L/MJ HDRD and 376.16 L/MJ HDRD for production through fast pyrolysis and the HTL process, respectively. Forest residues (i.e., chips from branches and tops generated during logging operations) have water requirements of 338.58 L/MJ HDRD and 255.85 L/MJ HDRD for production through fast pyrolysis and the HTL process, respectively. Agricultural residues (i.e., straw from wheat, oats, and barley), which are more water efficient, have water requirements of 83.7 L/MJ HDRD and 59.1 L/MJ HDRD through fast pyrolysis and the HTL process, respectively. Differences in water use between feedstocks and conversion processes indicate that the choices of biomass feedstock and conversion pathway water efficiency are crucial factors affecting water use efficiency of HDRD production.

  15. Dissipated energy and entropy production for an unconventional heat engine: the stepwise `circular cycle'

    NASA Astrophysics Data System (ADS)

    di Liberto, Francesco; Pastore, Raffaele; Peruggi, Fulvio

    2011-05-01

    When some entropy is transferred, by means of a reversible engine, from a hot heat source to a colder one, the maximum efficiency occurs, i.e. the maximum available work is obtained. Similarly, a reversible heat pumps transfer entropy from a cold heat source to a hotter one with the minimum expense of energy. In contrast, if we are faced with non-reversible devices, there is some lost work for heat engines, and some extra work for heat pumps. These quantities are both related to entropy production. The lost work, i.e. ? , is also called 'degraded energy' or 'energy unavailable to do work'. The extra work, i.e. ? , is the excess of work performed on the system in the irreversible process with respect to the reversible one (or the excess of heat given to the hotter source in the irreversible process). Both quantities are analysed in detail and are evaluated for a complex process, i.e. the stepwise circular cycle, which is similar to the stepwise Carnot cycle. The stepwise circular cycle is a cycle performed by means of N small weights, dw, which are first added and then removed from the piston of the vessel containing the gas or vice versa. The work performed by the gas can be found as the increase of the potential energy of the dw's. Each single dw is identified and its increase, i.e. its increase in potential energy, evaluated. In such a way it is found how the energy output of the cycle is distributed among the dw's. The size of the dw's affects entropy production and therefore the lost and extra work. The distribution of increases depends on the chosen removal process.

  16. 75 FR 53731 - Culturally Significant Objects Imported for Exhibition Determinations: “Contemporary Argentine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... Culturally Significant Objects Imported for Exhibition Determinations: ``Contemporary Argentine Masterworks... of August 28, 2000, I hereby determine that the objects to be included in the exhibition..., are of cultural significance. The objects are imported pursuant to loan agreements with the...

  17. Activity of Bifenthrin, Chlorfenapyr, Fipronil, and Thiamethoxam against Argentine Ants (Hymenoptera: Formicidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bifenthrin, chlorfenapyr, fipronil, and thiamethoxam were evaluated for activity against the Argentine ant, Linepithema humile (Mayr). Mobility impairment and lethal times were determined following topical treatments. Ants were immobilized most quickly by bifenthrin, followed by chlorfenapyr and th...

  18. Sustainability evaluation of pasteurized milk production with a life cycle assessment approach: An Iranian case study.

    PubMed

    Rafiee, Shahin; Khoshnevisan, Benyamin; Mohammadi, Issa; Aghbashlo, Mortaza; Mousazadeh, Hossein; Clark, Sean

    2016-08-15

    Agro-food systems play a significant role in the economies of all nations due to energy use and the resulting environmental consequences. The sustainability of these systems is determined by a multitude of interacting economic, social and environmental factors. Dairy production presents a relevant example of the sustainability trade-offs that occur within such systems. On the one hand, dairy production constitutes an important part of the human diet, but it is also responsible for significant emissions of potent greenhouse gases and other pollutants. In this study, the environmental aspects of pasteurized milk production in Iran were investigated using a life-cycle approach. Three sub-systems, namely feed production, dairy farm and dairy factory, were taken into account to determine how and where Iranian pasteurized milk production might be made more environmentally friendly and energy efficient. The results clearly demonstrate that the feed production stage was the hot spot in pasteurized milk production in terms of energy consumption, environmental burdens and economic costs. The largest share of the total production costs belonged to animal feeds (43%), which were part of the feed production stage. The largest consumers of energy in the production of raw milk were alfalfa (30.3%), concentrate (24%), straw (17.8%) and maize (10.9%) for cows, followed by diesel fuel (6.6%) and electricity (5.6%). The global warming potential for the production of 1000kg of raw milk at the dairy-farm gate was estimated at 457kg CO2,eq. Thus, more than 69% of the total impact at the milk-processing gate resulted from the previous two sub-systems (feed production and dairy farm), with the feed-production stage accounting for the largest fractions of the environmental burdens. PMID:27110976

  19. Sustainability evaluation of pasteurized milk production with a life cycle assessment approach: An Iranian case study.

    PubMed

    Rafiee, Shahin; Khoshnevisan, Benyamin; Mohammadi, Issa; Aghbashlo, Mortaza; Mousazadeh, Hossein; Clark, Sean

    2016-08-15

    Agro-food systems play a significant role in the economies of all nations due to energy use and the resulting environmental consequences. The sustainability of these systems is determined by a multitude of interacting economic, social and environmental factors. Dairy production presents a relevant example of the sustainability trade-offs that occur within such systems. On the one hand, dairy production constitutes an important part of the human diet, but it is also responsible for significant emissions of potent greenhouse gases and other pollutants. In this study, the environmental aspects of pasteurized milk production in Iran were investigated using a life-cycle approach. Three sub-systems, namely feed production, dairy farm and dairy factory, were taken into account to determine how and where Iranian pasteurized milk production might be made more environmentally friendly and energy efficient. The results clearly demonstrate that the feed production stage was the hot spot in pasteurized milk production in terms of energy consumption, environmental burdens and economic costs. The largest share of the total production costs belonged to animal feeds (43%), which were part of the feed production stage. The largest consumers of energy in the production of raw milk were alfalfa (30.3%), concentrate (24%), straw (17.8%) and maize (10.9%) for cows, followed by diesel fuel (6.6%) and electricity (5.6%). The global warming potential for the production of 1000kg of raw milk at the dairy-farm gate was estimated at 457kg CO2,eq. Thus, more than 69% of the total impact at the milk-processing gate resulted from the previous two sub-systems (feed production and dairy farm), with the feed-production stage accounting for the largest fractions of the environmental burdens.

  20. A model of the ocean iron cycle and its influence on biological production

    NASA Astrophysics Data System (ADS)

    Dutkiewicz, S.; Parekh, P.; Follows, M.

    2003-04-01

    Biological productivity in large regions of the ocean, specifically high nutrient, low chlorophyll regions, is limited by the deficit in iron relative to other nutrients. We have developed a parameterization of the iron cycle of the world's oceans which attempts to explicitly represent the processes by which this deficit in iron occurs. We have implemented this parameterization in the context of the MIT three dimensional global ocean model and examined the consequences for nutrient distributions, new production and primary production. The iron model parameterizes the mechanisms of scavenging of iron onto sinking particles and complexation with an organic ligand and is driven by specified aeolian flux patterns. First, using an idealized representation of export production, limited by light, phosphate and iron, the model reproduces the broad features of the observed ocean phosphate and iron distributions. We replace the simplified export parameterization with an explicit, but highly idealized, ecosystem model. The model represents a simplified food web with two phytoplankton size classes and a single grazer. The base currency for this model is phosphorus, but the larger phytoplankton class (i.e. diatoms) is also limited by silica. Both classes are limited by the availability of iron. The results of this model are also generally consistent with the observed patterns of phosphate and iron. In addition, the model captures the broad features of the distributions and cycles of silica, chlorophyll and primary production. We will also explore the sensitivities of this model to the forcing fields (e.g. aeolian iron flux) and parameter choices of the ecosystem model. This model represents a step towards the explicit representation of the ocean iron cycle, and its biogeochemical influences, in global biogeochemical models.

  1. Tectonics of the Argentine and Chilean Andes: An introduction

    NASA Astrophysics Data System (ADS)

    Folguera, Andrés; Alvarado, Patricia; Arriagada, César; Ramos, Victor A.

    2015-12-01

    This Special Issue gathers a series of contributions derived from presentations at the 19° Congreso Geológico Argentino held in Córdoba in 2-6 June 2014. Specific subjects cover a wide variety of topics and regions of the Argentine and Chilean Andes, varying from sedimentological analyses and U/Pb dating of detrital zircons in different rocks to determine source areas for different times and regions along the southern Andes; satellite gravity data for monitoring earthquakes at the subduction zone to understand their complex rupture structure; fission track data from the Andes to the foreland region; use of seismic tomographies and conventional seismic reflection data for analyzing crustal structure; to paleomagnetic data and structural and morphological analyses (Fig. 1).

  2. [How do we heal the Argentine health care system?].

    PubMed

    Tobar, Federico

    2002-04-01

    This article proposes a set of measures to reform the Argentine health care system and turn the country's current crisis into an opportunity for progressive, sustainable change. The proposal consists of a model for the intergovernmental division of health responsibilities. The national government would be responsible for strengthening its leadership role and for developing national insurance for low-prevalence high-cost diseases. With the provincial governments, the insurance role would be strengthened, with public health insurance making certain that there is universal coverage. Public hospitals would function as autonomous entities financed by social insurance, private insurance, and provincial public insurance. Municipalities would have an active role in disease prevention and health promotion, principally through primary care.

  3. The prevalence of chromosomal aberrations in Argentine air crew members.

    PubMed

    De Luca, Julio César; Picco, Sebastián Julio; Macintyre, Carlos; Dulout, Fernando Noel; Lopez-Larraza, Daniel Mario

    2009-01-01

    The authors analyzed the effects of chronic exposure of Argentine air crew members to low doses of ionizing radiations. Genetic damage induced by either low doses or low rates of ionizing radiation was higher than expected. Seventy-one heparinized blood samples were obtained from technical ground workers (group A; n = 10), pilots of domestic flights (group B; n = 14), pilots of transequatorial flights (group C; n = 17;), pilots of transpolar flights (group D; n = 17) and retired pilots (group E; n = 10) The frequency of dicentric chromosomes was higher in groups B and C compared with groups D and E. These observations suggest that the exposure of the aircraft to ionizing radiations may induce chromosomal aberrations. However, dicentric chromosomes in both domestic and retired pilots are still high compared with dicentric control participants. PMID:19395340

  4. Colorado Basin Structure and Rifting, Argentine passive margin

    NASA Astrophysics Data System (ADS)

    Autin, Julia; Scheck-Wenderoth, Magdalena; Loegering, Markus; Anka, Zahie; Vallejo, Eduardo; Rodriguez, Jorge; Marchal, Denis; Reichert, Christian; di Primio, Rolando

    2010-05-01

    The Argentine margin presents a strong segmentation with considerable strike-slip movements along the fracture zones. We focus on the volcanic segment (between the Salado and Colorado transfer zones), which is characterized by seaward dipping reflectors (SDR) all along the ocean-continent transition [e.g. Franke et al., 2006; Gladczenko et al., 1997; Hinz et al., 1999]. The segment is structured by E-W trending basins, which differs from the South African margin basins and cannot be explained by classical models of rifting. Thus the study of the relationship between the basins and the Argentine margin itself will allow the understanding of their contemporary development. Moreover the comparison of the conjugate margins suggests a particular evolution of rifting and break-up. We firstly focus on the Colorado Basin, which is thought to be the conjugate of the well studied Orange Basin [Hirsch et al., 2009] at the South African margin [e.g. Franke et al., 2006]. This work presents results of a combined approach using seismic interpretation and structural, isostatic and thermal modelling highlighting the structure of the crust. The seismic interpretation shows two rift-related discordances: one intra syn-rift and the break-up unconformity. The overlying sediments of the sag phase are less deformed (no sedimentary wedges) and accumulated before the generation of oceanic crust. The axis of the Colorado Basin trends E-W in the western part, where the deepest pre-rift series are preserved. In contrast, the basin axis turns to a NW-SE direction in its eastern part, where mainly post-rift sediments accumulated. The most distal part reaches the margin slope and opens into the oceanic basin. The general basin direction is almost orthogonal to the present-day margin trend. The most frequent hypothesis explaining this geometry is that the Colorado Basin is an aborted rift resulting from a previous RRR triple junction [e.g. Franke et al., 2002]. The structural interpretation

  5. Space Weather Impact on Pipeline in La Plata City, Argentine

    NASA Astrophysics Data System (ADS)

    Gianibelli, J. C.; Dovico, R. O.; Peirtti, R. O.; Pretel, R. O.; Garcia, R. E.; Quaglino, N. M.

    2007-05-01

    In the Sun-Earth connection, some of the most important characteristic events involved are the Coronal Mass Ejections (CME) and the high speed particle streams events coming from the Coronal Holes at the Sun. These interplanetary events produce effects on space and ground-based technology. In the present work, the geomagnetic storm recorded at Las Acacias Digital Magnetic Observatory (LAS, Lat.:-35º.0; Long.: 302º.3) produced by a particle stream from a solar coronal hole and their relationship with the induction effects caused on a pipeline in the shore of La Plata city, Argentine. The result shows an increase of the induced current correlated with the registered geomagnetic storm. Also, the magnetically calm days are analized. It is concluded that the amplitude of induced current intensity verifies a logarithmic relation with the amplitude of total magnetic intensity recorded in Las Acacias Observatory.

  6. Atmospheric leakage and condensate production in NASA's biomass production chamber. Effect of diurnal temperature cycles

    NASA Technical Reports Server (NTRS)

    Wheeler, Raymond M.; Drese, John H.; Sager, John C.

    1991-01-01

    A series of tests were conducted to monitor atmospheric leakage rate and condensate production in NASA's Biomass Production Chamber (BPC). Water was circulated through the 64 plant culture trays inside the chamber during the tests but no plants were present. Environmental conditions were set to a 12-hr photoperiod with either a matching 26 C (light)/20 C (dark) thermoperiod, or a constant 23 C temperature. Leakage, as determined by carbon dioxide decay rates, averaged about 9.8 percent for the 26 C/20 C regime and 7.3 percent for the constant 23 C regime. Increasing the temperature from 20 C to 26 C caused a temporary increase in pressure (up to 0.5 kPa) relative to ambient, while decreasing the temperature caused a temporary decrease in pressure of similar magnitude. Little pressure change was observed during transition between 23 C (light) and 23 C (dark). The lack of large pressure events under isothermal conditions may explain the lower leakage rate observed. When only the plant support inserts were placed in the culture trays, condensate production averaged about 37 liters per day. Placing acrylic germination covers over the tops of culture trays reduced condensate production to about 7 liters per day. During both tests, condensate production from the lower air handling system was 60 to 70 percent greater than from the upper system, suggesting imbalances exist in chilled and hot water flows for the two air handling systems. Results indicate that atmospheric leakage rates are sufficiently low to measure CO2 exchange rates by plants and the accumulation of certain volatile contaminants (e.g., ethylene). Control system changes are recommended in order to balance operational differences (e.g., humidity and temperature) between the two halves of the chamber.

  7. Testing baits to control Argentine ants (Hymenoptera: Formicidae) in vineyards.

    PubMed

    Daane, Kent M; Cooper, Monica L; Sime, Karen R; Nelson, Erik H; Battany, Mark C; Rust, Michael K

    2008-06-01

    Liquid baits were evaluated for control of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), and associated mealybug and soft scale pests in California vineyards. In 2003, liquid baits with small doses ofimidacloprid, boric acid, or thiamethoxam dissolved in 25% sucrose water resulted in lower ant and mealybug densities and fruit damage, compared with an untreated control. Similar treatments in a soft scale-infested vineyard showed only a reduction of ant density and fruit infestation in only the boric acid and thiamethoxam treatments. In 2004, commercial and noncommercial formulations of liquid baits reduced ant densities in three separate trials, but they had inconsistent effects on mealybug densities and fruit infestation; granular protein bait had no effect. Using large plots and commercial application methodologies, liquid bait deployed in June resulted in lower ant density and fruit infestation, but it had no effect on mealybug density. Across all trials, liquid bait treatments resulted in lower ant density (12 of 14 trials) and fruit damage (11 of 14 sites), presenting the first report of liquid baits applied using commercial methodologies that resulted in a reduction of ants and their associated hemipteran crop damage. For commercialization of liquid baits, we showed that any of the tested insecticides can suppress Argentine ants when properly delivered in the crop system. For imidacloprid, bait dispensers must be protected from sunlight to reduce photodegradation. Results suggest that incomplete ant suppression can suppress mealybug densities. However, after ant populations are suppressed, there may be a longer period before hemipteran populations are effectively suppressed. Therefore, liquid baits should be considered part of a multiseason program rather than a direct, in-season control of hemipteran pest populations.

  8. Soils of the Galindez Island, Argentine archipelago, Western Antarctica

    NASA Astrophysics Data System (ADS)

    Abakumov, Evgeny; Parnikoza, Ivan

    2015-04-01

    Antarctic Peninsula is a part of Antarctica which is characterized by increased soil diversity, caused by specific of parent materials and diversity of non-vascular and vascular plants. Soils of Galindez Island have been investigated during the 18-th Ukranian Antarctic Expedition 2013/14. This Island situated in Argentine archipelago (coastal part of Antarctic Peninsula). Soils of Galindez Island presented by following types: Leptosols, Lithosols, Histic Lithosols and Leptosols and some Gleyic soils, located in lowlands and coastal parts. An average solum profile thickness is 3-19 cm which result from the small depth of debris's, underplayed by massive crystallic rocks. The permafrost layer is located within the massive rock, but not in coarse friable parent material. The soils with bird influence are widely spread both in coastal and central part of Island. In the coastal parts we can find typical Ornithosols in the penguin rockeries areas. The main aim of our investigation was characterization of soils formed under vegetation, exactly under Deschampsia antarctica Desv. localities. Argentine Islands is the central part of D. antarctica spreading area in region of Antarctic peninsula. Probably, these islands colonized by hairgrass mainly due to ornitogenic activity. So, coastal population appearance related with Larus dominicanus nest areas and feeding activity. Thus, we found typical post ornithogenic soils here. This kind of soils we also observed in population of hairgrass of Galindez mainland where it was connected with the other Antarctic bird - Catharacta maccormicki activity. Thus, the soil diversity and soil geochemistry of the Galindez Island are closely related to the activity of birds. The spatial pattern of soils, their chemistry and organic matter quality is discussed in relation with distribution of bird nesting and feeding activity.

  9. Accelerator Reactor Coupling for Energy Production in Advanced Nuclear Fuel Cycles

    DOE PAGES

    Brown, Nicholas R.; Heidet, Florent; Haj Tahar, Malek

    2016-01-01

    This article is a review of several accelerator–reactor interface issues and nuclear fuel cycle applications of acceleratordriven subcritical systems. The systems considered here have the primary goal of energy production, but that goal is accomplished via a specific application in various proposed nuclear fuel cycles, such as breed-and-burn of fertile material or burning of transuranic material. Several basic principles are reviewed, starting from the proton beam window including the target, blanket, reactor core, and up to the fuel cycle. We focus on issues of interest, such as the impact of the energy required to run the accelerator and associated systemsmore » on the potential electricity delivered to the grid. Accelerator-driven systems feature many of the constraints and issues associated with critical reactors, with the added challenges of subcritical operation and coupling to an accelerator. Reliable accelerator operation and avoidance of beam trips are critically important. One interesting challenge is measurement of blanket subcriticality level during operation. We also review the potential benefits of accelerator-driven systems in various nuclear fuel cycle applications. Ultimately, accelerator-driven subcritical systems with the goal of transmutation of transuranic material have lower 100,000-year radioactivity than a critical fast reactor with recycling of uranium and plutonium.« less

  10. Accelerator Reactor Coupling for Energy Production in Advanced Nuclear Fuel Cycles

    SciTech Connect

    Brown, Nicholas R.; Heidet, Florent; Haj Tahar, Malek

    2016-01-01

    This article is a review of several accelerator–reactor interface issues and nuclear fuel cycle applications of acceleratordriven subcritical systems. The systems considered here have the primary goal of energy production, but that goal is accomplished via a specific application in various proposed nuclear fuel cycles, such as breed-and-burn of fertile material or burning of transuranic material. Several basic principles are reviewed, starting from the proton beam window including the target, blanket, reactor core, and up to the fuel cycle. We focus on issues of interest, such as the impact of the energy required to run the accelerator and associated systems on the potential electricity delivered to the grid. Accelerator-driven systems feature many of the constraints and issues associated with critical reactors, with the added challenges of subcritical operation and coupling to an accelerator. Reliable accelerator operation and avoidance of beam trips are critically important. One interesting challenge is measurement of blanket subcriticality level during operation. We also review the potential benefits of accelerator-driven systems in various nuclear fuel cycle applications. Ultimately, accelerator-driven subcritical systems with the goal of transmutation of transuranic material have lower 100,000-year radioactivity than a critical fast reactor with recycling of uranium and plutonium.

  11. Accelerator-Reactor Coupling for Energy Production in Advanced Nuclear Fuel Cycles

    NASA Astrophysics Data System (ADS)

    Heidet, Florent; Brown, Nicholas R.; Haj Tahar, Malek

    This article is a review of several accelerator-reactor interface issues and nuclear fuel cycle applications of accelerator-driven subcritical systems. The systems considered here have the primary goal of energy production, but that goal is accomplished via a specific application in various proposed nuclear fuel cycles, such as breed-and-burn of fertile material or burning of transuranic material. Several basic principles are reviewed, starting from the proton beam window including the target, blanket, reactor core, and up to the fuel cycle. We focus on issues of interest, such as the impact of the energy required to run the accelerator and associated systems on the potential electricity delivered to the grid. Accelerator-driven systems feature many of the constraints and issues associated with critical reactors, with the added challenges of subcritical operation and coupling to an accelerator. Reliable accelerator operation and avoidance of beam trips are critically important. One interesting challenge is measurement of blanket subcriticality level during operation. We also review the potential benefits of accelerator-driven systems in various nuclear fuel cycle applications. Ultimately, accelerator-driven subcritical systems with the goal of transmutation of transuranic material have lower 100,000-year radioactivity than a critical fast reactor with recycling of uranium and plutonium.

  12. Life Cycle Assessment of Switchgrass Cellulosic Ethanol Production in the Wisconsin and Michigan Agricultural Contexts

    SciTech Connect

    Sinistore, Julie C.; Reinemann, D. J.; Izaurralde, Roberto C.; Cronin, Keith R.; Meier, Paul J.; Runge, Troy M.; Zhang, Xuesong

    2015-04-25

    Spatial variability in yields and greenhouse gas emissions from soils has been identified as a key source of variability in life cycle assessments (LCAs) of agricultural products such as cellulosic ethanol. This study aims to conduct an LCA of cellulosic ethanol production from switchgrass in a way that captures this spatial variability and tests results for sensitivity to using spatially averaged results. The Environment Policy Integrated Climate (EPIC) model was used to calculate switchgrass yields, greenhouse gas (GHG) emissions, and nitrogen and phosphorus emissions from crop production in southern Wisconsin and Michigan at the watershed scale. These data were combined with cellulosic ethanol production data via ammonia fiber expansion and dilute acid pretreatment methods and region-specific electricity production data into an LCA model of eight ethanol production scenarios. Standard deviations from the spatial mean yields and soil emissions were used to test the sensitivity of net energy ratio, global warming potential intensity, and eutrophication and acidification potential metrics to spatial variability. Substantial variation in the eutrophication potential was also observed when nitrogen and phosphorus emissions from soils were varied. This work illustrates the need for spatially explicit agricultural production data in the LCA of biofuels and other agricultural products.

  13. Prospective life cycle assessment of graphene production by ultrasonication and chemical reduction.

    PubMed

    Arvidsson, Rickard; Kushnir, Duncan; Sandén, Björn A; Molander, Sverker

    2014-04-15

    One promising future bulk application of graphene is as composite additive. Therefore, we compare two production routes for in-solution graphene using a cradle-to-gate lifecycle assessment focusing on potential differences in energy use, blue water footprint, human toxicity, and ecotoxicity. The data used for the assessment is based on information in scientific papers and patents. Considering the prospective nature of this study, environmental impacts from background systems such as energy production were not included. The production routes are either based on ultrasonication or chemical reduction. The results show that the ultrasonication route has lower energy and water use, but higher human and ecotoxicity impacts, compared to the chemical reduction route. However, a sensitivity analysis showed that solvent recovery in the ultrasonication process gives lower impacts for all included impact categories. The sensitivity analysis also showed that solvent recovery is important to lower the blue water footprint of the chemical reduction route as well. The results demonstrate the possibility to conduct a life cycle assessment study based mainly on information from patents and scientific articles, enabling prospective life cycle assessment studies of products at early stages of technological development.

  14. Combinatorial life cycle assessment to inform process design of industrial production of algal biodiesel.

    PubMed

    Brentner, Laura B; Eckelman, Matthew J; Zimmerman, Julie B

    2011-08-15

    The use of algae as a feedstock for biodiesel production is a rapidly growing industry, in the United States and globally. A life cycle assessment (LCA) is presented that compares various methods, either proposed or under development, for algal biodiesel to inform the most promising pathways for sustainable full-scale production. For this analysis, the system is divided into five distinct process steps: (1) microalgae cultivation, (2) harvesting and/or dewatering, (3) lipid extraction, (4) conversion (transesterification) into biodiesel, and (5) byproduct management. A number of technology options are considered for each process step and various technology combinations are assessed for their life cycle environmental impacts. The optimal option for each process step is selected yielding a best case scenario, comprised of a flat panel enclosed photobioreactor and direct transesterification of algal cells with supercritical methanol. For a functional unit of 10 GJ biodiesel, the best case production system yields a cumulative energy demand savings of more than 65 GJ, reduces water consumption by 585 m(3) and decreases greenhouse gas emissions by 86% compared to a base case scenario typical of early industrial practices, highlighting the importance of technological innovation in algae processing and providing guidance on promising production pathways. PMID:21662987

  15. Combinatorial life cycle assessment to inform process design of industrial production of algal biodiesel.

    PubMed

    Brentner, Laura B; Eckelman, Matthew J; Zimmerman, Julie B

    2011-08-15

    The use of algae as a feedstock for biodiesel production is a rapidly growing industry, in the United States and globally. A life cycle assessment (LCA) is presented that compares various methods, either proposed or under development, for algal biodiesel to inform the most promising pathways for sustainable full-scale production. For this analysis, the system is divided into five distinct process steps: (1) microalgae cultivation, (2) harvesting and/or dewatering, (3) lipid extraction, (4) conversion (transesterification) into biodiesel, and (5) byproduct management. A number of technology options are considered for each process step and various technology combinations are assessed for their life cycle environmental impacts. The optimal option for each process step is selected yielding a best case scenario, comprised of a flat panel enclosed photobioreactor and direct transesterification of algal cells with supercritical methanol. For a functional unit of 10 GJ biodiesel, the best case production system yields a cumulative energy demand savings of more than 65 GJ, reduces water consumption by 585 m(3) and decreases greenhouse gas emissions by 86% compared to a base case scenario typical of early industrial practices, highlighting the importance of technological innovation in algae processing and providing guidance on promising production pathways.

  16. How Many Environmental Impact Indicators Are Needed in the Evaluation of Product Life Cycles?

    PubMed

    Steinmann, Zoran J N; Schipper, Aafke M; Hauck, Mara; Huijbregts, Mark A J

    2016-04-01

    Numerous indicators are currently available for environmental impact assessments, especially in the field of Life Cycle Impact Assessment (LCIA). Because decision-making on the basis of hundreds of indicators simultaneously is unfeasible, a nonredundant key set of indicators representative of the overall environmental impact is needed. We aimed to find such a nonredundant set of indicators based on their mutual correlations. We have used Principal Component Analysis (PCA) in combination with an optimization algorithm to find an optimal set of indicators out of 135 impact indicators calculated for 976 products from the ecoinvent database. The first four principal components covered 92% of the variance in product rankings, showing the potential for indicator reduction. The same amount of variance (92%) could be covered by a minimal set of six indicators, related to climate change, ozone depletion, the combined effects of acidification and eutrophication, terrestrial ecotoxicity, marine ecotoxicity, and land use. In comparison, four commonly used resource footprints (energy, water, land, materials) together accounted for 84% of the variance in product rankings. We conclude that the plethora of environmental indicators can be reduced to a small key set, representing the major part of the variation in environmental impacts between product life cycles.

  17. How Many Environmental Impact Indicators Are Needed in the Evaluation of Product Life Cycles?

    PubMed

    Steinmann, Zoran J N; Schipper, Aafke M; Hauck, Mara; Huijbregts, Mark A J

    2016-04-01

    Numerous indicators are currently available for environmental impact assessments, especially in the field of Life Cycle Impact Assessment (LCIA). Because decision-making on the basis of hundreds of indicators simultaneously is unfeasible, a nonredundant key set of indicators representative of the overall environmental impact is needed. We aimed to find such a nonredundant set of indicators based on their mutual correlations. We have used Principal Component Analysis (PCA) in combination with an optimization algorithm to find an optimal set of indicators out of 135 impact indicators calculated for 976 products from the ecoinvent database. The first four principal components covered 92% of the variance in product rankings, showing the potential for indicator reduction. The same amount of variance (92%) could be covered by a minimal set of six indicators, related to climate change, ozone depletion, the combined effects of acidification and eutrophication, terrestrial ecotoxicity, marine ecotoxicity, and land use. In comparison, four commonly used resource footprints (energy, water, land, materials) together accounted for 84% of the variance in product rankings. We conclude that the plethora of environmental indicators can be reduced to a small key set, representing the major part of the variation in environmental impacts between product life cycles. PMID:26963880

  18. Spermatogenic cycle length and sperm production in the freshwater turtle Kinosternon scorpioides.

    PubMed

    Sousa, Alana Lislea; Campos-Junior, Paulo Henrique Almeida; Costa, Guilherme Mattos Jardim; de França, Luiz Renato

    2014-02-01

    Kinosternon scorpioides is a Brazilian freshwater turtle that belongs to the class Reptilia, encompassing almost 10,000 species. Nevertheless, very little is known about the testicular quantitative parameters, particularly those related to spermatogenesis, in this vertebrate class. Our main objectives were to investigate in detail the structure and function of the testis in K. scorpioides, particularly the aspects related to spermatogenic cycle length and Sertoli cell (SC) and spermatogenic efficiencies. Nine sexually mature turtles were examined, and intraperitoneal bromodeoxyuridine injections were administered to estimate duration of spermatogenesis. Based on the acrosome development in spermatids and the overall germ cell associations, 10 stages of the seminiferous epithelium cycle were characterized. Similar to birds, humans, and some primate species, several stages were observed per seminiferous tubule cross-sections. One spermatogenic cycle and the entire spermatogenic process lasted, respectively, 12 and 53 days. The SC efficiency (number of round spermatids per SC) and daily sperm production per gram of testis were, respectively, 20 and 40 million spermatids. As established for mammals, our findings suggest that SC efficiency is also a critical determinant of sperm production in reptiles. To our knowledge, this is the first study to investigate the kinetics of spermatogenesis and testis function in any reptilian species. Besides allowing a better understanding of reproductive biology in reptiles, these data will be useful in comparative studies. Moreover, these results could provide the basis for investigations related to the evaluation of spermatogonial stem cell physiology niche in Kinosternon scorpioides. PMID:24403547

  19. Life cycle assessment of biohydrogen production as a transportation fuel in Germany.

    PubMed

    Wulf, Christina; Kaltschmitt, Martin

    2013-12-01

    The goal of this work was to study the assessment of the life cycle of hydrogen production from biomass for transportation purposes concerning greenhouse gas emissions, emissions with an acidification potential and the fossil energy demand. As feedstocks woody biomass from forestry or short rotation coppice, herbaceous biomass (i.e., straw), energy crops (mainly maize and grain), bio-waste and organic by-products (e.g., glycerol) were considered and their potential in Germany assessed. The results showed that hydrogen produced from woody biomass emitted the least emissions due to the low emissions caused by the provision of the biomass. Regarding the cumulative fossil energy demand biomass from short rotation coppice showed the lowest values. The highest biomass potential for hydrogen production could be identified for woody biomass from forests as well as from short rotation coppice.

  20. Status of the DOE /STOR/-sponsored national program on hydrogen production from water via thermochemical cycles

    NASA Technical Reports Server (NTRS)

    Baker, C. E.

    1977-01-01

    A pure thermochemical cycle is a system of linked regenerative chemical reactions which accepts only water and heat and produces hydrogen. Thermochemical cycles are potentially a more efficient and cheaper means of producing hydrogen from water than is the generation of electricity followed by electrolysis. The Energy Storage Systems Division of the Department of Energy is currently funding a national program on thermochemical hydrogen production. The National Aeronautics and Space Administration is responsible for the technical management of this program. The goal is to develop a cycle which can potentially operate with an efficiency greater than 40% using a heat source providing a maximum available temperature of 1150 K. A closed bench-scale demonstration of such a cycle would follow. This cycle would be labeled a 'reference cycle' and would serve as a baseline against which future cycles would be compared.

  1. Biomass production and chemical cycling in a man-made geothermal wetland

    SciTech Connect

    Breckenridge, R.P.; Wheeler, L.R.; Ginsburg, J.F.

    1983-06-01

    Biomass production and, to a lesser extent, chemical cycling have been evaluated in a man-made wetland created using geothermal water in southcentral Idaho. The wetland system consisted of a 0.25 ha area divided into two ponds. The upper pond contained submerged species (Egeria, pondweeds and coontail); the lower pond was planted with emergents (cattail, bulrush, and common reed). Biomass production from emergent plants in the two-year-old system was promising and compared favorably with production values reported in the literature for natural wetlands. Chemical cycling of potassium (K) was evaluated through the lower pond system. Uptake of several other constituents (F and Na) of the geothermal water by the emergent plants was observed. However, there was little difference in elemental concentrations of the system's influent and effluent, probably due to evapotranspiration of water which effectively concentrates elements in the remaining water. Twenty-one species of diatoms were identified in the geothermal wetland, and numerous species of insects were observed. The man-made wetland also created substantial habitat for wildlife. This type of system could be used as an alternative to injection of spent geothermal fluids from small-scale projects. Study results indicate that a wetland system can be developed to produce substantial quantities of biomass in a cold desert environment.

  2. Increased production of cellulase of Trichoderma sp. by pH cycling and temperature profiling

    SciTech Connect

    Mukhopadhyay, S.N.; Malik, R.K.

    1980-11-01

    Cultivation of Trichoderma reesei QM 9414 on 3% (w/v) cellulose medium (C/N ratio equal to 8.5) produced 4.5 IU/ml cellulase in 180 hr at a cell growth of 8.0 g/liter (0.266 g cell/g cellulose). It corresponded to an average cellulase productivity 25.0 IU/liter/hr (3.5 IU/g cell/hr. In the same medium 9.5 g/liter cell mass (0.316 g cell/g cellulose), 6.2 IU/ml cellulase, and 38.75 IU/liter/hr (4.0 IU/g cell/hr) cellulase productivity could be obtained using pH cycling condition during cultivation. Cell mass, cellulase yield, and productivity were further increased to 10.0 g/liter, 7.2 IU/ml and 44.0 IU/liter/hr (4.5 IU/g cell/hr), respectively, by simultaneous pH cycling and temperature profiling strategy. Results are described.

  3. Cryoprotectant Production in Freeze-Tolerant Wood Frogs Is Augmented by Multiple Freeze-Thaw Cycles.

    PubMed

    Larson, Don J; Barnes, Brian M

    2016-01-01

    Ice nucleation across the skin of wood frogs (Lithobates sylvaticus) rapidly induces endogenous production of glucose, a cryoprotectant necessary for freeze tolerance. In laboratory studies of freeze tolerance, wood frogs are cooled slowly, often at -0.05°C h(-1), to facilitate high cryoprotectant production and survival. Under natural conditions in Alaska, however, wood frogs accumulate maximal tissue glucose concentrations while cooling at much faster rates, -0.35° to -1.6°C h(-1), and in addition undergo multiple successive freeze-thaw cycles before remaining frozen for the winter. We examined whether simulating these ecologically relevant cooling rates and repeated freeze-thaw events in captive wood frogs results in the high glucose concentrations found in naturally frozen wood frogs. We found that over successive freezing and thawing events, glucose concentrations increased stepwise in all measured tissues. Short thawing periods did not result in a statistically significant decline of glucose concentrations. Wood frogs that experienced three freeze-thaw events had fresh weight glucose concentrations that approached values found in tissues of wood frogs frozen in natural conditions. Laboratory wood frogs survive frozen for 2 mo, while wood frogs frozen under natural conditions survive frozen for up to 7 mo at temperatures below -18°C. We hypothesize that repeated freeze-thaw cycles with rapid cooling and warming rates allow for greater survival in Alaskan wood frogs through enhanced cryoprotectant production. PMID:27327184

  4. Cryoprotectant Production in Freeze-Tolerant Wood Frogs Is Augmented by Multiple Freeze-Thaw Cycles.

    PubMed

    Larson, Don J; Barnes, Brian M

    2016-01-01

    Ice nucleation across the skin of wood frogs (Lithobates sylvaticus) rapidly induces endogenous production of glucose, a cryoprotectant necessary for freeze tolerance. In laboratory studies of freeze tolerance, wood frogs are cooled slowly, often at -0.05°C h(-1), to facilitate high cryoprotectant production and survival. Under natural conditions in Alaska, however, wood frogs accumulate maximal tissue glucose concentrations while cooling at much faster rates, -0.35° to -1.6°C h(-1), and in addition undergo multiple successive freeze-thaw cycles before remaining frozen for the winter. We examined whether simulating these ecologically relevant cooling rates and repeated freeze-thaw events in captive wood frogs results in the high glucose concentrations found in naturally frozen wood frogs. We found that over successive freezing and thawing events, glucose concentrations increased stepwise in all measured tissues. Short thawing periods did not result in a statistically significant decline of glucose concentrations. Wood frogs that experienced three freeze-thaw events had fresh weight glucose concentrations that approached values found in tissues of wood frogs frozen in natural conditions. Laboratory wood frogs survive frozen for 2 mo, while wood frogs frozen under natural conditions survive frozen for up to 7 mo at temperatures below -18°C. We hypothesize that repeated freeze-thaw cycles with rapid cooling and warming rates allow for greater survival in Alaskan wood frogs through enhanced cryoprotectant production.

  5. Life Cycle, Feeding and Production of Isoptena serricornis(Pictet, 1841)

    NASA Astrophysics Data System (ADS)

    Derka, Tomá; Tierno de Figueroa, José Manuel; Krno, Il'ja

    2004-05-01

    Some aspects of the biology and ecology (life cycle, feeding and production) of a population of Isoptena serricornis in the Rudava River (Slovakia) are studied, reported and discussed. The life cycle is annual, with slow growth in autumn-winter and fast growth in late summer and spring. The growth decreased two weeks before the Fall Equinox and increased two weeks after the Spring Equinox. The flight period spans from the end of May to the beginning of July. The presence of large sand particles in the gut of all studied nymphs is of note, and indicates that I. serricornis acts as a deposit-collector species. Nymphal food is principally composed of detritus, unicellular organisms and, in nymphs of intermediate or large size, Chironomidae larvae. Adult food is composed fundamentally of different types of pollen grains. Males usually have lower food content than females. Annual production of this species (694-750 mg · m-2) is very high in relation to other previously studied Chloroperlidae. This is probably largely responsible for I. serricornis being one of the most abundant components of the macroinvertebrate community in its habitat in the Rudava River. A negative correlation between production and temperature was observed.

  6. Uncertainty quantification metrics for whole product life cycle cost estimates in aerospace innovation

    NASA Astrophysics Data System (ADS)

    Schwabe, O.; Shehab, E.; Erkoyuncu, J.

    2015-08-01

    The lack of defensible methods for quantifying cost estimate uncertainty over the whole product life cycle of aerospace innovations such as propulsion systems or airframes poses a significant challenge to the creation of accurate and defensible cost estimates. Based on the axiomatic definition of uncertainty as the actual prediction error of the cost estimate, this paper provides a comprehensive overview of metrics used for the uncertainty quantification of cost estimates based on a literature review, an evaluation of publicly funded projects such as part of the CORDIS or Horizon 2020 programs, and an analysis of established approaches used by organizations such NASA, the U.S. Department of Defence, the ESA, and various commercial companies. The metrics are categorized based on their foundational character (foundations), their use in practice (state-of-practice), their availability for practice (state-of-art) and those suggested for future exploration (state-of-future). Insights gained were that a variety of uncertainty quantification metrics exist whose suitability depends on the volatility of available relevant information, as defined by technical and cost readiness level, and the number of whole product life cycle phases the estimate is intended to be valid for. Information volatility and number of whole product life cycle phases can hereby be considered as defining multi-dimensional probability fields admitting various uncertainty quantification metric families with identifiable thresholds for transitioning between them. The key research gaps identified were the lacking guidance grounded in theory for the selection of uncertainty quantification metrics and lacking practical alternatives to metrics based on the Central Limit Theorem. An innovative uncertainty quantification framework consisting of; a set-theory based typology, a data library, a classification system, and a corresponding input-output model are put forward to address this research gap as the basis

  7. [The modification of nitric oxide production by exogenous substrates of Krebs cycle during acute hypoxia].

    PubMed

    Kurhaliuk, N M; Kotsiuruba, A V; Sahach, V F

    2005-01-01

    Hypoxia causes the disruption of mitochondria electron respiratory chain, production of active oxygen forms and the unoxidative protection. In experiments on Wistar rats the influence of sodium succinate (50 mg/kg) and 6-ketoglutarate (200 mg/kg) on NO2-, NO3-, urea and polyamines contents in blood and liver under acute hypoxia (7% O2 in N2, 30 min) was investigated. Nitrite and nitrate content decreased in erythrocytes and liver but not in plasma under acute hypoxia. The exogenous succinate (SK) stimulated production of nitric oxide in erythrocytes and liver while 6-ketoglutarate (KG) only in liver. The switch from more intensive SK oxidation that reveals adrenomimetic influence and causes the synthesis and release of NO from erythrocyte, to less intensive KG correlates with well-known decrease of tissue respiration under the activation of the cholinergic system due to urea cycle activation particularly in liver. The activation of the SK oxidation takes place mainly under the different stress conditions and causes NO production in the blood cells. These conditions of the intensive and fast action under acute hypoxia are accompanied on the one hand by the increase of oxygen input ratio and on the other hand by activation of the free radical oxidation. The protective effect of the natural Krebs cycle intermediates--SK and KG in particular, is related to the regulation of NO synthesis and its metabolism in the main organs. These results proved the existence not only metabolite control of NO system by Krebs cycle intermediates, but the existence of the systemic mechanism for the support of the functional state of mitochondria under hypoxia.

  8. Red meat production in australia: life cycle assessment and comparison with overseas studies.

    PubMed

    Peters, Gregory M; Rowley, Hazel V; Wiedemann, Stephen; Tucker, Robyn; Short, Michael D; Schulz, Matthias

    2010-02-15

    Greenhouse gas emissions from beef production are a significant part of Australia's total contribution to climate change. For the first time an environmental life cycle assessment (LCA) hybridizing detailed on-site process modeling and input-output analysis is used to describe Australian red meat production. In this paper we report the carbon footprint and total energy consumption of three supply chains in three different regions in Australia over two years. The greenhouse gas (GHG) emissions and energy use data are compared to those from international studies on red meat production, and the Australian results are either average or below average. The increasing proportion of lot-fed beef in Australia is favorable, since this production system generates lower total GHG emissions than grass-fed production; the additional effort in producing and transporting feeds is effectively offset by the increased efficiency of meat production in feedlots. In addition to these two common LCA indicators, in this paper we also quantify solid waste generation and a soil erosion indicator on a common basis. PMID:20067280

  9. Using Life Cycle Assessment methodology to assess UHT milk production in Portugal.

    PubMed

    González-García, Sara; Castanheira, Erica G; Dias, Ana Cláudia; Arroja, Luis

    2013-01-01

    Milk and dairy products constitute an important ingredient in the human diet. Ultra-high temperature (UHT) milk is the main dairy product consumed in Portugal and its production entails large inputs of resources which derive on negative environmental effects such as nutrient enrichment of the ecosystem and climate change. In this study, Life Cycle Assessment (LCA) methodology was considered for the environmental assessment of packaged UHT milk produced in Portugal, including simple (whole, semi-skimmed and skimmed) and cocoa milk from a cradle-to-gate perspective and to identify the environmental hot spots. Results showed that the production of the raw milk in the dairy farm is the main hot spot in almost all the categories under assessment mainly due to the emissions from enteric fermentation, manure management and fertilisers production and application. Furthermore, on-site emissions derived from dairy factory are remarkable together with the packages and energy requirements production. The values reported in this study are in the range of other related papers. However, differences were also identified due to several reasons such as allocation approach, data sources, characterisation factors, farm management regimes and assumptions considered. Therefore, these aspects should be carefully addressed and sensitivity to the assumptions and uncertainty of the results should be evaluated. PMID:23178782

  10. Biohydrogen production by immobilized Chlorella sp. using cycles of oxygenic photosynthesis and anaerobiosis.

    PubMed

    Song, Wei; Rashid, Naim; Choi, Wookjin; Lee, Kisay

    2011-09-01

    Hydrogen production was studied using immobilized green alga Chlorella sp. through a two-stage cyclic process where immobilized cells were first incubated in oxygenic photosynthesis followed by anaerobic incubation for H2 production in the absence of sulfur. Chlorella sp. used in this study was capable of generating H2 under immobilized state in agar. The externally added glucose enhanced H2 production rates and total produced volume while shortened the lag time required for cell adaptation prior to H2 evolution. The rate of hydrogen evolution was increased as temperature increased, and the maximum evolution rate under 30 mM glucose was 183 mL/h/L and 238 mL/h/L at 37 °C and 40 °C, respectively. In order to continue repeated cycles of H2 production, at least two days of photosynthesis stage should be allowed for cells to recover H2 production potential and cell viability before returning to H2 production stage again.

  11. Red meat production in australia: life cycle assessment and comparison with overseas studies.

    PubMed

    Peters, Gregory M; Rowley, Hazel V; Wiedemann, Stephen; Tucker, Robyn; Short, Michael D; Schulz, Matthias

    2010-02-15

    Greenhouse gas emissions from beef production are a significant part of Australia's total contribution to climate change. For the first time an environmental life cycle assessment (LCA) hybridizing detailed on-site process modeling and input-output analysis is used to describe Australian red meat production. In this paper we report the carbon footprint and total energy consumption of three supply chains in three different regions in Australia over two years. The greenhouse gas (GHG) emissions and energy use data are compared to those from international studies on red meat production, and the Australian results are either average or below average. The increasing proportion of lot-fed beef in Australia is favorable, since this production system generates lower total GHG emissions than grass-fed production; the additional effort in producing and transporting feeds is effectively offset by the increased efficiency of meat production in feedlots. In addition to these two common LCA indicators, in this paper we also quantify solid waste generation and a soil erosion indicator on a common basis.

  12. Assessment of dose during the life cycle of natural stone production.

    PubMed

    Turtiainen, Tuukka; Weltner, Anne

    2007-01-01

    The environmental impact during the life cycle of natural stone production was studied. One of the points of interest was radiation. Natural stone samples from 23 quarries were surveyed for the radioactivity. One quarry was selected for a case study where the effective dose to the workers was assessed. The use of these stones in buildings was also evaluated with respect to the excess dose caused to the residents. According to the results the excess effective dose to the workers does not exceed 1 mSv a(-1) at the quarries. In buildings, all natural stones studied can be used safely as surfacing materials.

  13. Minifactory: a precision assembly system adaptable to the product life cycle

    NASA Astrophysics Data System (ADS)

    Muir, Patrick F.; Rizzi, Alfred A.; Gowdy, Jay W.

    1997-12-01

    Automated product assembly systems are traditionally designed with the intent that they will be operated with few significant changes for as long as the product is being manufactured. This approach to factory design and programming has may undesirable qualities which have motivated the development of more 'flexible' systems. In an effort to improve agility, different types of flexibility have been integrated into factory designs. Specifically, automated assembly systems have been endowed with the ability to assemble differing products by means of computer-controlled robots, and to accommodate variations in parts locations and dimensions by means of sensing. The product life cycle (PLC) is a standard four-stage model of the performance of a product from the time that it is first introduced in the marketplace until the time that it is discontinued. Manufacturers can improve their return on investment by adapting the production process to the PLC. We are developing two concepts to enable manufacturers to more readily achieve this goal: the agile assembly architecture (AAA), an abstract framework for distributed modular automation; and minifactory, our physical instantation of this architecture for the assembly of precision electro-mechanical devices. By examining the requirements which each PLC stage places upon the production system, we identify characteristics of factory design and programming which are appropriate for that stage. As the product transitions from one stage to the next, the factory design and programing should also transition from one embodiment to the next in order to achieve the best return on investment. Modularity of the factory components, highly flexible product transport mechanisms, and a high level of distributed intelligence are key characteristics of minifactory that enable this adaptation.

  14. Microalgal productivity in an estuarine lake during a drought cycle: The St. Lucia Estuary, South Africa

    NASA Astrophysics Data System (ADS)

    van der Molen, Johan S.; Perissinotto, Renzo

    2011-03-01

    The St. Lucia estuarine lake on the north coast of KwaZulu-Natal, South Africa, is one of the largest estuarine systems in Africa and of unique importance for the adjacent marine and terrestrial ecosystems. The area regularly experiences periods of drought, resulting in hypersaline conditions in its shallow lakes and the closure of the estuarine mouth. This study aimed to assess the primary production rates of phytoplankton and microphytobenthos throughout an annual cycle of this drought phase. Primary production rates were assessed at representative sites, namely the Mouth, Narrows, South and North Lakes from June 2006 to May 2007. Because of the drought, the salinity gradient from the mouth to the head of the estuary was reversed by comparison to estuarine systems with a steady freshwater inflow and regular marine exchange. In March 2007, during the study, the mouth opened as a result of rough seas, and the marine influence broke the existing reversed gradient, producing a marine salinity throughout the system. Microphytobenthic primary productivity varied between 0 and 34 mg C m -2 h -1 and showed strong correlations with salinity, DIN:DIP ratios and irradiance. Benthic productivity was high across the system after breaching of the mouth. Pelagic primary productivity (between 0 and 180 mg C m -2 h -1), showed a correlation with temperature and irradiance and was highest across the system in February 2007 when the mouth was still closed. There was no significant correlation between production rates and biomass (chl-a) in either the benthic or pelagic habitats. The negative correlation between DIN:DIP ratio and benthic primary productivity indicated that phosphorus was the limiting nutrient. This study shows that salinity, along with seasonally dependent parameters such as temperature and irradiance, correlates with the rate of microalgal production. Hence, in these shallow lakes, the largest primary productivity can occur in either the pelagic or benthic

  15. Life cycle greenhouse gas impacts of ethanol, biomethane and limonene production from citrus waste

    NASA Astrophysics Data System (ADS)

    Pourbafrani, Mohammad; McKechnie, Jon; MacLean, Heather L.; Saville, Bradley A.

    2013-03-01

    The production of biofuel from cellulosic residues can have both environmental and financial benefits. A particular benefit is that it can alleviate competition for land conventionally used for food and feed production. In this research, we investigate greenhouse gas (GHG) emissions associated with the production of ethanol, biomethane, limonene and digestate from citrus waste, a byproduct of the citrus processing industry. The study represents the first life cycle-based evaluations of citrus waste biorefineries. Two biorefinery configurations are studied—a large biorefinery that converts citrus waste into ethanol, biomethane, limonene and digestate, and a small biorefinery that converts citrus waste into biomethane, limonene and digestate. Ethanol is assumed to be used as E85, displacing gasoline as a light-duty vehicle fuel; biomethane displaces natural gas for electricity generation, limonene displaces acetone in solvents, and digestate from the anaerobic digestion process displaces synthetic fertilizer. System expansion and two allocation methods (energy, market value) are considered to determine emissions of co-products. Considerable GHG reductions would be achieved by producing and utilizing the citrus waste-based products in place of the petroleum-based or other non-renewable products. For the large biorefinery, ethanol used as E85 in light-duty vehicles results in a 134% reduction in GHG emissions compared to gasoline-fueled vehicles when applying a system expansion approach. For the small biorefinery, when electricity is generated from biomethane rather than natural gas, GHG emissions are reduced by 77% when applying system expansion. The life cycle GHG emissions vary substantially depending upon biomethane leakage rate, feedstock GHG emissions and the method to determine emissions assigned to co-products. Among the process design parameters, the biomethane leakage rate is critical, and the ethanol produced in the large biorefinery would not meet EISA

  16. Farm and product carbon footprints of China's fruit production--life cycle inventory of representative orchards of five major fruits.

    PubMed

    Yan, Ming; Cheng, Kun; Yue, Qian; Yan, Yu; Rees, Robert M; Pan, Genxing

    2016-03-01

    Understanding the environmental impacts of fruit production will provide fundamental information for policy making of fruit consumption and marketing. This study aims to characterize the carbon footprints of China's fruit production and to figure out the key greenhouse gas emissions to cut with improved orchard management. Yearly input data of materials and energy in a full life cycle from material production to fruit harvest were obtained via field visits to orchards of five typical fruit types from selected areas of China. Carbon footprint (CF) was assessed with quantifying the greenhouse gas emissions associated with the individual inputs. Farm and product CFs were respectively predicted in terms of land use and of fresh fruit yield. Additionally, product CFs scaled by fruit nutrition value (vitamin C (Vc) content) and by the economic benefit from fruit production were also evaluated. The estimated farm CF ranged from 2.9 to 12.8 t CO2-eq ha(-1) across the surveyed orchards, whereas the product CF ranged from 0.07 to 0.7 kg CO2-eq kg(-1) fruit. While the mean product CFs of orange and pear were significantly lower than those of apple, banana, and peach, the nutrition-scaled CF of orange (0.5 kg CO2-eq g(-1) Vc on average) was significantly lower than others (3.0-5.9 kg CO2-eq g(-1) Vc). The income-scaled CF of orange and pear (1.20 and 1.01 kg CO2-eq USD(-1), respectively) was higher than apple, banana, and peach (0.87~0.39 kg CO2-eq USD(-1)). Among the inputs, synthetic nitrogen fertilizer contributed by over 50 % to the total greenhouse gas (GHG) emissions, varying among the fruit types. There were some tradeoffs in product CFs between fruit nutrition value and fruit growers' income. Low carbon production and consumption policy and marketing mechanism should be developed to cut down carbon emissions from fruit production sector, with balancing the nutrition value, producer's income, and climate change mitigation. PMID:26527344

  17. Farm and product carbon footprints of China's fruit production--life cycle inventory of representative orchards of five major fruits.

    PubMed

    Yan, Ming; Cheng, Kun; Yue, Qian; Yan, Yu; Rees, Robert M; Pan, Genxing

    2016-03-01

    Understanding the environmental impacts of fruit production will provide fundamental information for policy making of fruit consumption and marketing. This study aims to characterize the carbon footprints of China's fruit production and to figure out the key greenhouse gas emissions to cut with improved orchard management. Yearly input data of materials and energy in a full life cycle from material production to fruit harvest were obtained via field visits to orchards of five typical fruit types from selected areas of China. Carbon footprint (CF) was assessed with quantifying the greenhouse gas emissions associated with the individual inputs. Farm and product CFs were respectively predicted in terms of land use and of fresh fruit yield. Additionally, product CFs scaled by fruit nutrition value (vitamin C (Vc) content) and by the economic benefit from fruit production were also evaluated. The estimated farm CF ranged from 2.9 to 12.8 t CO2-eq ha(-1) across the surveyed orchards, whereas the product CF ranged from 0.07 to 0.7 kg CO2-eq kg(-1) fruit. While the mean product CFs of orange and pear were significantly lower than those of apple, banana, and peach, the nutrition-scaled CF of orange (0.5 kg CO2-eq g(-1) Vc on average) was significantly lower than others (3.0-5.9 kg CO2-eq g(-1) Vc). The income-scaled CF of orange and pear (1.20 and 1.01 kg CO2-eq USD(-1), respectively) was higher than apple, banana, and peach (0.87~0.39 kg CO2-eq USD(-1)). Among the inputs, synthetic nitrogen fertilizer contributed by over 50 % to the total greenhouse gas (GHG) emissions, varying among the fruit types. There were some tradeoffs in product CFs between fruit nutrition value and fruit growers' income. Low carbon production and consumption policy and marketing mechanism should be developed to cut down carbon emissions from fruit production sector, with balancing the nutrition value, producer's income, and climate change mitigation.

  18. Spermatogenic cycle length and sperm production in a feral pig species (collared peccary, Tayassu tajacu).

    PubMed

    Costa, Guilherme M J; Leal, Marcelo C; Silva, Jurupytan V; Ferreira, Ana Cássia S; Guimarães, Diva A; França, Luiz Renato de

    2010-01-01

    Although the collared peccary (Tayassu tajacu) is found throughout the Americas, with a high potential for domestication and commercial exploitation, there are few data on the reproductive biology of this mammalian species. The aim of the present study was to investigate testis structure, spermatogenic cycle length, Sertoli cell efficiency, and spermatogenic efficiency. Twelve adult peccaries were used for biometrical, histological, and stereological analyses; 3 of these peccaries received intratesticular injections of (3)H-thymidine for the determination of the duration of spermatogenesis. Testis weight and gonadosomatic index were 23.7 +/- 1.8 g and 0.2% +/- 0.1%, respectively. Seminiferous tubule volume density was 77.4% +/- 1.7%. Leydig cells occupied 12.8% +/- 1.8% of the testis parenchyma and presented a peculiar cytoarchitecture in the periphery of the seminiferous tubule lobes. The premeiotic, meiotic, and postmeiotic stage frequencies were very similar to those found for wild and domestic boars. The spermatogenic cycle and entire spermatogenic process (based on 4.5 cycles) lasted approximately 12.3 +/- 0.2 and 55.1 +/- 0.7 days, respectively. Daily sperm production per gram of testis in the collared peccary was approximately 23.4 +/- 2 x 10(6), which is similar to that of domestic and wild boars. The knowledge generated in the present study could be used in reproduction and animal improvement programs and provides important information that may be used for comparative reproductive biology with previously investigated mammalian species.

  19. Production of hydrogen from coke-oven gas by the short-cycle adsorption method

    SciTech Connect

    Podorozhanskii, M.M.; Plichko, V.S.; Shustikov, V.I.; Yavorskaya, Z.G.

    1981-01-01

    In recent years the short-cycle adsorption method has been extensively used to separate hydrogen from hydrogen-containing gases in the petrochemical and chemical industries. With regard to coke-oven gas, which contains about 60% hydrogen, this problem has been given less attention in the literature. As the adsorbent, molecular sieves obtained from carbon have been used. Investigation of the process on a pilot apparatus demonstrated the possibility of using this method to produce hydrogen at a concentration of 95 to 99%. We have obtained similar data using an IGI (Institute of Fossil Fuels) microbead adsorbent with micropore volume of about 0.35 cm/sup 3//g. As a result of the experiments, it was concluded that: (1) the short-cycle adsorption method may be used to produce technical hydrogen suitable for use in hydrorefining processes; (2) an equation was derived describing the degree of purity of the hydrogen as a function of the productivity of a unit of adsorbent volume, the quantity of blowout gases and the duration of the cycle.

  20. FRAMEWORK FOR RESPONSIBLE ENVIRONMENTAL DECISION-MAKING (FRED): USING LIFE CYCLE ASSESSMENT TO EVALUATE PREFERABILITY OF PRODUCTS

    EPA Science Inventory

    Framework for Responsible Environmental Decision-Making (FRED) demonstrates how the life-cycle concept can be used to quantify competing products' environmental performance so that this information may be integrated with considerations of total ownership cost and technical perfor...

  1. Characterization of Argentine honeys on the basis of their mineral content and some typical quality parameters

    PubMed Central

    2014-01-01

    Background The levels of 19 elements (As, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Tl, U, V, Zn) from sixteen different Argentine production sites of unifloral [eucalyptus (Eucaliptus rostrata), chilca (Baccharis salicifolia), Algarrobo (Prosopis sp.), mistol (Ziziphus mistol) and citric] and multifloral honeys were measured with the aim to test the quality of the selected samples. Typical quality parameters of honeys were also determined (pH, sugar content, moisture). Mineral elements were determined by using inductively coupled plasma mass spectrometer (ICP-MS DRC). We also evaluated the suitability of honey as a possible biomonitor of environmental pollution. Thus, the sites were classified through cluster analysis (CA) and then pattern recognition methods such as Principal Component Analysis (PCA) and discriminant analysis (DA) were applied. Results Mean values for quality parameters were: pH, 4.12 and 3.81; sugar 82.1 and 82.0 °brix; moisture, 16.90 and 17.00% for unifloral and multifloral honeys respectively. The water content showed good maturity. Likewise, the other parameters confirmed the good quality of the honeys analysed. Potassium was quantitatively the most abundant metal, accounting for 92,5% of the total metal contents with an average concentration of 832.0 and 816.2 μg g-1 for unifloral and multifloral honeys respectively. Sodium was the second most abundant major metal in honeys with a mean value of 32.16 and 33.19 μg g-1 for unifloral and multifloral honeys respectively. Mg, Ca, Fe, Mn, Zn and Cu were present at low-intermediate concentrations. For the other 11 trace elements determined in this study (As, Be, Cd, Co, Cr, Ni, Pb, Se, Tl, U and V), the mean concentrations were very low or below of the LODs. The sites were classified through CA by using elements’ and physicochemical parameters data, then DA on the PCA factors was applied. Dendrograms identified three main groups. PCA explained 52.03% of the total variability

  2. Resource consumption and environmental impacts of the agrofood sector: life cycle assessment of italian citrus-based products.

    PubMed

    Beccali, Marco; Cellura, Maurizio; Iudicello, Maria; Mistretta, Marina

    2009-04-01

    Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance. PMID:19184189

  3. Resource Consumption and Environmental Impacts of the Agrofood Sector: Life Cycle Assessment of Italian Citrus-Based Products

    NASA Astrophysics Data System (ADS)

    Beccali, Marco; Cellura, Maurizio; Iudicello, Maria; Mistretta, Marina

    2009-04-01

    Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.

  4. The Primary and Secondary Production of Germanium: A Life-Cycle Assessment of Different Process Alternatives

    NASA Astrophysics Data System (ADS)

    Robertz, Benedicte; Verhelle, Jensen; Schurmans, Maarten

    2015-02-01

    Germanium is a semiconducting metalloid element used in optical fibers, catalysis, infrared optics, solar cells, and light-emitting diodes. The need for Ge in these markets is considered to increase by a steady ~1% on a yearly basis. Its economic importance, coupled with the identified supply risks, has led to the classification of germanium as a critical raw material within Europe. Since the early 1950s, Umicore Electro-Optic Materials has supplied germanium-based materials solutions to its markets around the world. Umicore extracts germanium from a wide range of refining and recycling feeds. The main objectives of this study were to quantify the potential environmental impacts of the production of germanium from production scraps from the photovoltaic industry and to compare them with the potential impacts of the primary production of germanium from coal. The data related to the secondary production are Umicore-specific data. Environmental impact scores have been calculated for the impact categories recommended by the International reference life cycle data system. The comparison of the primary and secondary production highlights the benefit linked to the recycling of metals.

  5. Quantifying subtropical North Pacific gyre mixed layer primary productivity from Seaglider observations of diel oxygen cycles

    NASA Astrophysics Data System (ADS)

    Nicholson, David P.; Wilson, Samuel T.; Doney, Scott C.; Karl, David M.

    2015-05-01

    Using autonomous underwater gliders, we quantified diurnal periodicity in dissolved oxygen, chlorophyll, and temperature in the subtropical North Pacific near the Hawaii Ocean Time-series (HOT) Station ALOHA during summer 2012. Oxygen optodes provided sufficient stability and precision to quantify diel cycles of average amplitude of 0.6 µmol kg-1. A theoretical diel curve was fit to daily observations to infer an average mixed layer gross primary productivity (GPP) of 1.8 mmol O2 m-3 d-1. Cumulative net community production (NCP) over 110 days was 500 mmol O2 m-2 for the mixed layer, which averaged 57 m in depth. Both GPP and NCP estimates indicated a significant period of below-average productivity at Station ALOHA in 2012, an observation confirmed by 14C productivity incubations and O2/Ar ratios. Given our success in an oligotrophic gyre where biological signals are small, our diel GPP approach holds promise for remote characterization of productivity across the spectrum of marine environments.

  6. Comparison of Asian Aquaculture Products by Use of Statistically Supported Life Cycle Assessment.

    PubMed

    Henriksson, Patrik J G; Rico, Andreu; Zhang, Wenbo; Ahmad-Al-Nahid, Sk; Newton, Richard; Phan, Lam T; Zhang, Zongfeng; Jaithiang, Jintana; Dao, Hai M; Phu, Tran M; Little, David C; Murray, Francis J; Satapornvanit, Kriengkrai; Liu, Liping; Liu, Qigen; Haque, M Mahfujul; Kruijssen, Froukje; de Snoo, Geert R; Heijungs, Reinout; van Bodegom, Peter M; Guinée, Jeroen B

    2015-12-15

    We investigated aquaculture production of Asian tiger shrimp, whiteleg shrimp, giant river prawn, tilapia, and pangasius catfish in Bangladesh, China, Thailand, and Vietnam by using life cycle assessments (LCAs), with the purpose of evaluating the comparative eco-efficiency of producing different aquatic food products. Our starting hypothesis was that different production systems are associated with significantly different environmental impacts, as the production of these aquatic species differs in intensity and management practices. In order to test this hypothesis, we estimated each system's global warming, eutrophication, and freshwater ecotoxicity impacts. The contribution to these impacts and the overall dispersions relative to results were propagated by Monte Carlo simulations and dependent sampling. Paired testing showed significant (p < 0.05) differences between the median impacts of most production systems in the intraspecies comparisons, even after a Bonferroni correction. For the full distributions instead of only the median, only for Asian tiger shrimp did more than 95% of the propagated Monte Carlo results favor certain farming systems. The major environmental hot-spots driving the differences in environmental performance among systems were fishmeal from mixed fisheries for global warming, pond runoff and sediment discards for eutrophication, and agricultural pesticides, metals, benzalkonium chloride, and other chlorine-releasing compounds for freshwater ecotoxicity. The Asian aquaculture industry should therefore strive toward farming systems relying upon pelleted species-specific feeds, where the fishmeal inclusion is limited and sourced sustainably. Also, excessive nutrients should be recycled in integrated organic agriculture together with efficient aeration solutions powered by renewable energy sources.

  7. Life cycle and production of chironomidae (diptera) in Biandantang, a typical macrophytic lake (Hubei, China)

    NASA Astrophysics Data System (ADS)

    Yun-Jun, Yan

    2000-09-01

    The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang Lake at eight stations from April, 1996 to March, 1997. Instarfrequency data showed C. plumosus was univoltine, while the other three were bivoltine. Production in wet weight (g/(m2·a)) calculated by the size-frequency method for each species were: C. plumosus, 2.663; Chironomus sp., 1.161; Clinotanypus sp., 0.270; T. akamusi, 1.476. Based on the mean standing stock, their P/B ratios were 3.2, 4.0, 6.2, and 4.4, respectively.

  8. Hybrid fusion reactor for production of nuclear fuel with minimum radioactive contamination of the fuel cycle

    NASA Astrophysics Data System (ADS)

    Velikhov, E. P.; Kovalchuk, M. V.; Azizov, E. A.; Ignatiev, V. V.; Subbotin, S. A.; Tsibulskiy, V. F.

    2015-12-01

    The paper presents the results of the system research on the coordinated development of nuclear and fusion power engineering in the current century. Considering the increasing problems of resource procurement, including limited natural uranium resources, it seems reasonable to use fusion reactors as high-power neutron sources for production of nuclear fuel in a blanket. It is shown that the share of fusion sources in this structural configuration of the energy system can be relatively small. A fundamentally important aspect of this solution to the problem of closure of the fuel cycle is that recycling of highly active spent fuel can be abandoned. Radioactivity released during the recycling of the spent fuel from the hybrid reactor blanket is at least two orders of magnitude lower than during the production of the same number of fissile isotopes after the recycling of the spent fuel from a fast reactor.

  9. Life-cycle energy production and emissions mitigation by comprehensive biogas-digestate utilization.

    PubMed

    Chen, Shaoqing; Chen, Bin; Song, Dan

    2012-06-01

    In the context of global energy shortages and climate change, developing biogas plants with links to agricultural system has become an important strategy for cleaner rural energy and renewable agriculture. In this study, a life-cycle energy and environmental assessment was performed for a biogas-digestate utilization system in China. The results suggest that biogas utilization (heating, illumination, and fuel) and comprehensive digestate reuse are of equal importance in the total energy production of the system, and they also play an important role in systemic greenhouse gas mitigation. Improvement can be achieved in both energy production and emissions mitigation when the ratio of the current three biogas utilization pathways is adjusted. Regarding digestate reuse, a tradeoff between energy and environmental performance can be obtained by focusing on the substitution for top-dressing, base fertilizers, and the application to seed soaking.

  10. Life cycle assessment of advanced bioethanol production from pulp and paper sludge.

    PubMed

    Sebastião, Diogo; Gonçalves, Margarida S; Marques, Susana; Fonseca, César; Gírio, Francisco; Oliveira, Ana C; Matos, Cristina T

    2016-05-01

    This work evaluates the environmental performance of using pulp and paper sludge as feedstock for the production of second generation ethanol. An ethanol plant for converting 5400 tons of dry sludge/year was modelled and evaluated using a cradle-to-gate life cycle assessment approach. The sludge is a burden for pulp and paper mills that is mainly disposed in landfilling. The studied system allows for the valorisation of the waste, which due to its high polysaccharide content is a valuable feedstock for bioethanol production. Eleven impact categories were analysed and the results showed that enzymatic hydrolysis and neutralisation of the CaCO3 are the environmental hotspots of the system contributing up to 85% to the overall impacts. Two optimisation scenarios were evaluated: (1) using a reduced HCl amount in the neutralisation stage and (2) co-fermentation of xylose and glucose, for maximal ethanol yield. Both scenarios displayed significant environmental impact improvements.

  11. Sensitivity analysis in a life cycle assessment of an aged red wine production from Catalonia, Spain.

    PubMed

    Meneses, M; Torres, C M; Castells, F

    2016-08-15

    Sustainability in agriculture and food processing is an issue with a clear growing interest; especially in products were consumers have particular awareness regarding its environmental profile. This is the case of wine industry depending on grape production, winemaking and bottling. Also viticulture and generally agricultural production is significantly affected by climate variations. The aim of this article is to determine the environmental load of an aged red wine from a winery in Catalonia, Spain, over its entire life cycle, including sensitivity analysis of the main parameters related to the cultivation, vinification and bottling. The life cycle assessment (LCA) methodology is used for the environmental analysis. In a first step, life cycle inventory (LCI) data were collected by questionnaires and interviews with the winemaker, all data are actual operating data and all the stages involved in the production have been taken into account (viticulture, vinification, bottling and the disposal subsystem). Data were then used to determine the environmental profile by a life cycle impact assessment using the ReCiPe method. Annual variability in environmental performance, stresses the importance of including timeline analysis in the wine sector. Because of that this study is accompanied with a sensitivity analysis carried out by a Monte Carlo simulation that takes into account the uncertainty and variability of the parameters used. In this manner, the results are presented with confidence intervals to provide a wider view of the environmental issues derived from the activities of the studied wine estate regardless of the eventualities of a specific harvesting year. Since the beverage packaging has an important influence in this case, a dataset for the production of green glass was adapted to reflect the actual recycling situation in Spain. Furthermore, a hypothetical variation of the glass-recycling rate in the glass production completes this article, as a key variable

  12. Life cycle assessment on biogas production from straw and its sensitivity analysis.

    PubMed

    Wang, Qiao-Li; Li, Wei; Gao, Xiang; Li, Su-Jing

    2016-02-01

    This study aims to investigate the synthetically environmental impacts and Global Warming Potentials (GWPs) of straw-based biogas production process via cradle-to-gate life cycle assessment (LCA) technique. Eco-indicator 99 (H) and IPCC 2007 GWP with three time horizons are utilized. The results indicate that the biogas production process shows beneficial effect on synthetic environment and is harmful to GWPs. Its harmful effects on GWPs are strengthened with time. Usage of gas-fired power which burns the self-produced natural gas (NG) can create a more sustainable process. Moreover, sensitivity analysis indicated that total electricity consumption and CO2 absorbents in purification unit have the largest sensitivity to the environment. Hence, more efforts should be made on more efficient use of electricity and wiser selection of CO2 absorbent. PMID:26649899

  13. Hybrid fusion reactor for production of nuclear fuel with minimum radioactive contamination of the fuel cycle

    SciTech Connect

    Velikhov, E. P.; Kovalchuk, M. V.; Azizov, E. A. Ignatiev, V. V.; Subbotin, S. A. Tsibulskiy, V. F.

    2015-12-15

    The paper presents the results of the system research on the coordinated development of nuclear and fusion power engineering in the current century. Considering the increasing problems of resource procurement, including limited natural uranium resources, it seems reasonable to use fusion reactors as high-power neutron sources for production of nuclear fuel in a blanket. It is shown that the share of fusion sources in this structural configuration of the energy system can be relatively small. A fundamentally important aspect of this solution to the problem of closure of the fuel cycle is that recycling of highly active spent fuel can be abandoned. Radioactivity released during the recycling of the spent fuel from the hybrid reactor blanket is at least two orders of magnitude lower than during the production of the same number of fissile isotopes after the recycling of the spent fuel from a fast reactor.

  14. Life cycle assessment on biogas production from straw and its sensitivity analysis.

    PubMed

    Wang, Qiao-Li; Li, Wei; Gao, Xiang; Li, Su-Jing

    2016-02-01

    This study aims to investigate the synthetically environmental impacts and Global Warming Potentials (GWPs) of straw-based biogas production process via cradle-to-gate life cycle assessment (LCA) technique. Eco-indicator 99 (H) and IPCC 2007 GWP with three time horizons are utilized. The results indicate that the biogas production process shows beneficial effect on synthetic environment and is harmful to GWPs. Its harmful effects on GWPs are strengthened with time. Usage of gas-fired power which burns the self-produced natural gas (NG) can create a more sustainable process. Moreover, sensitivity analysis indicated that total electricity consumption and CO2 absorbents in purification unit have the largest sensitivity to the environment. Hence, more efforts should be made on more efficient use of electricity and wiser selection of CO2 absorbent.

  15. Life cycle assessment of bioethanol production from woodchips with modifications in the pretreatment process.

    PubMed

    Shadbahr, Jalil; Zhang, Yan; Khan, Faisal

    2015-01-01

    Pretreatment as a crucial step in the process of ethanol production has significant influences on the process efficiency and on the environmental performance of the bioethanol production from lignocellulosic biomass. In present life cycle analysis (LCA) study, two cases for pretreatment of woodchips were considered as the focal point of the ethanol plant. One was assumed as base scenario whereas the second is the proposed alternative by implementation of modifications on the base design. In the first stage, LCA results of pretreatment unit showed lower environmental impacts in respiratory inorganics and land use than in new scenario, while the base scenario revealed better performance in fossil fuels. The results of the second stage of LCA study demonstrated improvement in proposed design in most categories of environmental impacts such as 18.5 % in land use as well as 17 % improvement in ecosystem quality. PMID:25367284

  16. Life cycle assessment on microalgal biodiesel production using a hybrid cultivation system.

    PubMed

    Adesanya, Victoria O; Cadena, Erasmo; Scott, Stuart A; Smith, Alison G

    2014-07-01

    A life cycle assessment (LCA) was performed on a putative biodiesel production plant in which the freshwater alga Chlorella vulgaris, was grown using an existing system similar to a published commercial-scale hybrid cultivation. The hybrid system couples airlift tubular photobioreactors with raceway ponds in a two-stage process for high biomass growth and lipid accumulation. The results show that microalgal biodiesel production would have a significantly lower environmental impact than fossil-derived diesel. Based on the functional unit of 1 ton of biodiesel produced, the hybrid cultivation system and hypothetical downstream process (base case) would have 42% and 38% savings in global warming potential (GWP) and fossil-energy requirements (FER) when compared to fossil-derived diesel, respectively. Sensitivity analysis was performed to identify the most influential process parameters on the LCA results. The maximum reduction in GWP and FER was observed under mixotrophic growth conditions with savings of 76% and 75% when compared to conventional diesel, respectively.

  17. Sensitivity analysis in a life cycle assessment of an aged red wine production from Catalonia, Spain.

    PubMed

    Meneses, M; Torres, C M; Castells, F

    2016-08-15

    Sustainability in agriculture and food processing is an issue with a clear growing interest; especially in products were consumers have particular awareness regarding its environmental profile. This is the case of wine industry depending on grape production, winemaking and bottling. Also viticulture and generally agricultural production is significantly affected by climate variations. The aim of this article is to determine the environmental load of an aged red wine from a winery in Catalonia, Spain, over its entire life cycle, including sensitivity analysis of the main parameters related to the cultivation, vinification and bottling. The life cycle assessment (LCA) methodology is used for the environmental analysis. In a first step, life cycle inventory (LCI) data were collected by questionnaires and interviews with the winemaker, all data are actual operating data and all the stages involved in the production have been taken into account (viticulture, vinification, bottling and the disposal subsystem). Data were then used to determine the environmental profile by a life cycle impact assessment using the ReCiPe method. Annual variability in environmental performance, stresses the importance of including timeline analysis in the wine sector. Because of that this study is accompanied with a sensitivity analysis carried out by a Monte Carlo simulation that takes into account the uncertainty and variability of the parameters used. In this manner, the results are presented with confidence intervals to provide a wider view of the environmental issues derived from the activities of the studied wine estate regardless of the eventualities of a specific harvesting year. Since the beverage packaging has an important influence in this case, a dataset for the production of green glass was adapted to reflect the actual recycling situation in Spain. Furthermore, a hypothetical variation of the glass-recycling rate in the glass production completes this article, as a key variable

  18. Consistency analysis of the water cycle from recently derived satellite products

    NASA Astrophysics Data System (ADS)

    Berbery, E. H.; Hain, C.; Anderson, M. C.; Zhan, X.; Liu, J.; Ferraro, R. R.; Adler, R. F.; Wu, H.

    2015-12-01

    NOAA's National Environmental Satellite, Data, and Information Service (NESDIS) develops environmental data from satellites and other sources that is a critical resource for the management of energy, water, and food supplies. Variables related to the water cycle are routinely computed from satellite remote sensing from several space agencies, and the products are used at NOAA in operational or experimental modes. This study seeks to investigate to what extent there is consistency among the diverse products, and how they represent the water cycle at different scales. Remote sensing of land surface temperature and radiation is used to estimate surface energy fluxes by means of the Atmosphere Land Exchange Inverse (ALEXI) model. An Evaporative Stress Index representing anomalies in the ratio of actual-to-potential is a reliable indicator of drought also obtained from the ALEXI model. Observations from all currently available microwave satellite sensors are processed and merged to obtain the best possible estimates of soil moisture. The Global Soil Moisture Operational Product System (SMOPS) may also ingest brightness temperature observations applying a single channel algorithm to retrieve soil moisture. All satellite retrievals in SMOPS are merged into a soil moisture product that includes proxies of the errors. The Global Precipitation Climatology Project (GPCP) monthly precipitation data set (a current NOAA CDR project) uses satellite precipitation data sets over ocean and satellite plus gauge-based analyses over land. For operational needs, NESDIS's Hydro-Estimator (H-E) uses infrared data from GOES to estimate higher temporal resolution (sub-daily) rainfall rates. Streamflow at all the river mouths is estimated by the Dominant river tracing-Routing Integrated with VIC Environment model using precipitation input and other forcing data. Evapotranspiration, soil moisture, precipitation, streamflow and groundwater are derived at different resolutions, time scales and

  19. The formation of Pliocene sapropels and carbonate cycles in the Mediterranean: Diagenesis, dilution, and productivity

    NASA Astrophysics Data System (ADS)

    van Os, B. J. H.; Lourens, L. J.; Hilgen, F. J.; de Lange, G. J.; Beaufort, L.

    1994-08-01

    High-resolution micropaleontological (planktonic foraminifera and calcareous nannofossils) and geochemical (stable isotopes, organic carbon, Fe, P, S, Ca, Ba, Mn, and Al) records are presented for the first sapropel-containing carbonate cycle in the Pliocene of Sicily. The carbonate cycle is characterized by a gray to white to beige to white color layering typical of the marls of the Trubi formation. A faintly laminated sapropel is intercalated in the gray-colored bed of the carbonate cycle. CaCO3 content varies from 40% in the beige to 45-50% in the white layers. Lowest CaCO3 content of 25-30% is found in the gray layer and sapropel. Variations in carbonate and organic matter percentages can best be explained by changes in paleoproductivity rather than by variations in dilution and dissolution. Total productivity was highest during deposition of the gray layer and sapropel, as indicated by high organic carbon and Ba contents and high abundance of Globorotalia puncticulata. Carbonate production reached its highest values, however, during deposition of the white layers, as evidenced by enhanced abundances of planktonic foraminifera and nannofossils. The low carbonate content in the gray layer and sapropel is explained in terms of a collapse in carbonate production caused by extreme changes in the physical and biochemical properties of the water column, which in turn resulted in siliceous plankton and opportunistic foraminifers such as Globorotalia puncticulata outcompeting most calcareous organisms. The beige layer represents a low-productivity environment similar to the present-day eastern Mediterranean basin. Several mechanisms have previously been proposed to explain variations in productivity in the eastern Mediterranean. Both sapropels and gray layers were deposited at times when perihelion occurred in northern hemisphere summer. We envisage that the increase in seasonal contrast resulting from this orbital configuration enhanced winter mixing and stabilization

  20. HTGR-GT closed-cycle gas turbine. A plant concept with inherent cogeneration, power plus heat production, capability

    NASA Astrophysics Data System (ADS)

    McDonald, C. F.

    1980-04-01

    The high grade sensible heat rejection characteristic of the high temperature gas cooled reactor gas turbine plant is suited to cogeneration. Cogeneration broadly covers combined power and heat operation modes. Cogeneration in this nuclear closed cycle plant includes: (1) bottoming Rankine cycle, (2) hot water or process steam production, (3) desalination, and (4) urban and industrial district heating. The HTGR-CT plant thermodynamic cycles, design features, and potential applications for the cogeneration operation modes are discussed. The HTGR-CT plant, which potentially approaches 50 percent overall efficiency in a combined cycle mode, can significantly aid national energy goals, particularly resource conservation.

  1. HTGR-GT closed-cycle gas turbine: a plant concept with inherent cogeneration (power plus heat production) capability

    SciTech Connect

    McDonald, C.F.

    1980-04-01

    The high-grade sensible heat rejection characteristic of the high-temperature gas-cooled reactor-gas turbine (HTGR-GT) plant is ideally suited to cogeneration. Cogeneration in this nuclear closed-cycle plant could include (1) bottoming Rankine cycle, (2) hot water or process steam production, (3) desalination, and (4) urban and industrial district heating. This paper discusses the HTGR-GT plant thermodynamic cycles, design features, and potential applications for the cogeneration operation modes. This paper concludes that the HTGR-GT plant, which can potentially approach a 50% overall efficiency in a combined cycle mode, can significantly aid national energy goals, particularly resource conservation.

  2. Production of seed samples for the effective molecular analysis of dormancy cycling in Arabidopsis.

    PubMed

    Footitt, Steven; Finch-Savage, William E

    2011-01-01

    Most often, the samples used for molecular analysis of dormancy are populations of seeds. An essential survival characteristic of seed populations inhabiting the variable surface layers of the soil is that individuals in the population do not behave uniformly. In addition, seed dormancy (SD) status of the whole population constantly changes even in the dry state. For these and other reasons, production of appropriate and adequately characterized seed samples is the key to the correct and most informative interpretation of molecular studies. This is particularly important when the aim is to describe and explain seed behaviour in the natural environment. Molecular studies of seed dormancy, and especially ecologically relevant behaviour, such as dormancy cycling, should therefore involve characterization of dormancy status based on a sound understanding of seed physiology. This chapter discusses the problems and pitfalls of using Arabidopsis and provides protocols devised for use with the Arabidopsis ecotype Cape Verde Islands for the production and characterization of samples to be used in molecular analysis of dormancy transitions and cycling. PMID:21898250

  3. The crustal structure of the southern Argentine margin

    NASA Astrophysics Data System (ADS)

    Becker, Katharina; Franke, Dieter; Schnabel, Michael; Schreckenberger, Bernd; Heyde, Ingo; Krawczyk, Charlotte M.

    2012-06-01

    Multichannel reflection seismic profiles, combined with gravimetric and magnetic data provide insight into the crustal structure of the southernmost Argentine margin, at the transition from a rifted to a transform margin and outline the extent of the North Falkland Graben. Based on these data, we establish a regional stratigraphic model for the post-rift sediments, comprising six marker horizons with a new formation in the Barremian/Lower Cretaceous. Our observations support that a N-S trending subsidiary branch of the North Falkland Graben continues along the continental shelf and slope to the Argentine basin. During the rift phase, a wide shelf area was affected by the E-W extension, subsequently forming the North Falkland Graben and the subsidiary branch along which finally breakup occurred. We propose the division of the margin in two segments: a N-S trending rifted margin and an E-W trending transform margin. This is further underpinned by crustal scale gravity modelling. Three different tectono-dynamic processes shaped the study area. (1) The Triassic/Early Jurassic extensional phase resulting in the formation of the North Falkland Graben and additional narrower rift grabens ended synchronously with the breakup of the South Atlantic in the early Valanginian. (2) Extensional phase related to the opening of the South Atlantic. (3) The transform margin was active in the study area from about Hauterivian times and activity lasted until late Cretaceous/early Cenozoic. Both, the rifted margin and the transform margin are magma-poor. Very limited structures may have a volcanic origin but are suggested to be post-rift. The oceanic crust was found to be unusually thin, indicating a deficit in magma supply during formation. These findings in combination with the proposed breakup age in the early Valanginian that considerably predates the formation of the Paraná-Etendeka continental flood basalt provinces in Brazil and Namibia question the influence of the Tristan da

  4. Energy analyses and greenhouse gas emissions assessment for saffron production cycle.

    PubMed

    Bakhtiari, Amir Abbas; Hematian, Amir; Sharifi, Azin

    2015-10-01

    Population growth and world climate changes are putting high pressure on agri-food production systems. Exacerbating use of energy sources and expanding the environmental damaging symptoms are the results of these difficult situations. This study was conducted to determine the energy balance for saffron production cycle and investigate the corresponding greenhouse gas (GHG) emissions in Iran. Saffron (Crocus sativus L.) is one of the main spice that historically cultivated in Iran. Data were obtained from 127 randomly selected saffron growers using a face to face questionnaire technique. The results revealed that in 5 years of saffron production cycle, the overall input and output energy use were to be 163,912.09 and 184,868.28 MJ ha(-1), respectively. The highest-level of energy consumption belongs to seeds (23.7 %) followed by chemical fertilizers (23.4 %). Energy use efficiency, specific energy, net energy, and energy productivity of saffron production were 1.1, 13.4 MJ kg(-1), 20,956.2 MJ ha(-1), and 0.1 kg MJ(-1), respectively. The result shows that the cultivation of saffron emits 2325.5 kg CO2 eq. ha(-1) greenhouse gas, in which around 46.5 % belonged to electricity followed by chemical fertilizers. In addition the Cobb-Douglas production function was applied into EViews 7 software to define the functional relationship. The results of econometric model estimation showed that the impact of human labor, electricity, and water for irrigation on stigma, human labor, electricity, and seed on corm and also human labor and farmyard manure (FYM) on flower and leaf yield were found to be statistically significant. Sensitivity analysis results of the energy inputs demonstrated that the marginal physical productivity (MPP) worth of electricity energy was the highest for saffron stigma and corm, although saffron flower and leaf had more sensitivity on chemicals energy inputs. Moreover, MPP values of renewable and indirect energies were higher than non-renewable and

  5. A New Global LAI Product and Its Use for Terrestrial Carbon Cycle Estimation

    NASA Astrophysics Data System (ADS)

    Chen, J. M.; Liu, R.; Ju, W.; Liu, Y.

    2014-12-01

    For improving the estimation of the spatio-temporal dynamics of the terrestrial carbon cycle, a new time series of the leaf area index (LAI) is generated for the global land surface at 8 km resolution from 1981 to 2012 by combining AVHRR and MODIS satellite data. This product differs from existing LAI products in the following two aspects: (1) the non-random spatial distribution of leaves with the canopy is considered, and (2) the seasonal variation of the vegetation background is included. The non-randomness of the leaf spatial distribution in the canopy is considered using the second vegetation structural parameter named clumping index (CI), which quantifies the deviation of the leaf spatial distribution from the random case. Using the MODIS Bidirectional Reflectance Distribution Function product, a global map of CI is produced at 500 m resolution. In our LAI algorithm, CI is used to convert the effective LAI obtained from mono-angle remote sensing into the true LAI, otherwise LAI would be considerably underestimated. The vegetation background is soil in crop, grass and shrub but includes soil, grass, moss, and litter in forests. Through processing a large volume of MISR data from 2000 to 2010, monthly red and near-infrared reflectances of the vegetation background is mapped globally at 1 km resolution. This new LAI product has been validated extensively using ground-based LAI measurements distributed globally. In carbon cycle modeling, the use of CI in addition to LAI allows for accurate separation of sunlit and shaded leaves as an important step in terrestrial photosynthesis and respiration modeling. Carbon flux measurements over 100 sites over the globe are used to validate an ecosystem model named Boreal Ecosystem Productivity Simulator (BEPS). The validated model is run globally at 8 km resolution for the period from 1981 to 2012 using the LAI product and other spatial datasets. The modeled results suggest that changes in vegetation structure as quantified

  6. Energy analyses and greenhouse gas emissions assessment for saffron production cycle.

    PubMed

    Bakhtiari, Amir Abbas; Hematian, Amir; Sharifi, Azin

    2015-10-01

    Population growth and world climate changes are putting high pressure on agri-food production systems. Exacerbating use of energy sources and expanding the environmental damaging symptoms are the results of these difficult situations. This study was conducted to determine the energy balance for saffron production cycle and investigate the corresponding greenhouse gas (GHG) emissions in Iran. Saffron (Crocus sativus L.) is one of the main spice that historically cultivated in Iran. Data were obtained from 127 randomly selected saffron growers using a face to face questionnaire technique. The results revealed that in 5 years of saffron production cycle, the overall input and output energy use were to be 163,912.09 and 184,868.28 MJ ha(-1), respectively. The highest-level of energy consumption belongs to seeds (23.7 %) followed by chemical fertilizers (23.4 %). Energy use efficiency, specific energy, net energy, and energy productivity of saffron production were 1.1, 13.4 MJ kg(-1), 20,956.2 MJ ha(-1), and 0.1 kg MJ(-1), respectively. The result shows that the cultivation of saffron emits 2325.5 kg CO2 eq. ha(-1) greenhouse gas, in which around 46.5 % belonged to electricity followed by chemical fertilizers. In addition the Cobb-Douglas production function was applied into EViews 7 software to define the functional relationship. The results of econometric model estimation showed that the impact of human labor, electricity, and water for irrigation on stigma, human labor, electricity, and seed on corm and also human labor and farmyard manure (FYM) on flower and leaf yield were found to be statistically significant. Sensitivity analysis results of the energy inputs demonstrated that the marginal physical productivity (MPP) worth of electricity energy was the highest for saffron stigma and corm, although saffron flower and leaf had more sensitivity on chemicals energy inputs. Moreover, MPP values of renewable and indirect energies were higher than non-renewable and

  7. Environmental impact of using specialty feed ingredients in swine and poultry production: A life cycle assessment.

    PubMed

    Kebreab, E; Liedke, A; Caro, D; Deimling, S; Binder, M; Finkbeiner, M

    2016-06-01

    Livestock production has a variety of environmental impacts such as greenhouse gas emissions, water pollution, acidification, and primary energy consumption. The demand for livestock products is expected to grow substantially, creating even more environmental pressure. The use of specialty feed ingredients (SFI) such as supplemented AA and phytase can reduce nutrient input into the system without compromising productivity and consequently can reduce emissions. The global change impact of using SFI in pig and broiler production systems in Europe and North and South America was studied. A life cycle assessment according to international standards (ISO 14040/44) analyzed contributions from producing SFI and animals to global change. Three different alternatives were analyzed. In addition, partial sensitivity analysis was conducted using 5 scenarios for each region for both production systems. Specialty feed ingredient supplementation in pig and broiler diets reduced greenhouse gas emissions (cradle to farm gate) by 56% and 54% in Europe, 17% and 15% in North America, and 33% and 19% in South America, respectively, compared to an unsupplemented diet. A total of 136 Mt CO equivalent (CO eq) was saved in 2012, rising to 146 Mt CO eq in 2050 on the basis of United Nations population projections. Considerable benefits of supplementation with SFI were apparent in European and South American diets when direct land use change was considered because of the reduced demand for soybean meal. The eutrophication potential of unsupplemented diets was reduced by up to 35% in pig and 49% in broiler production systems compared to supplemented alternatives. The acidification potential of supplemented strategies was reduced by up to 30% in pig and 79% in broiler production systems. The primary energy demand was similar in all alternatives, and this could be an area where the SFI industry can improve. Overall, SFI supplementation substantially reduced the global warming, eutrophication

  8. Diet and genotype effects on the quality index of beef produced in the Argentine Pampeana region.

    PubMed

    Latimori, N J; Kloster, A M; García, P T; Carduza, F J; Grigioni, G; Pensel, N A

    2008-07-01

    Steers of varying genotypes (Aberdeen Angus, Charolais x AA and Argentine Holstein) in four feeding systems were evaluated. Feeding systems were: S1=a diet based on pastures only; S2=a similar forage base as S1 plus a daily supplementation with cracked corn, at 0.7% of l.w./head/day; S3=a similar forage base as S1 plus a daily supplementation with cracked corn, at 1.0% of l.w./head/day; and S4=a regular feedlot diet. Tenderness and marbling were not affected by the feeding system. Feedlot meat showed an n-6/n-3 ratio significantly higher than meat produced with the diets based on pastures (S1=2.1; S2=3.1; S3=4.5; S4=14.2) (P<0.05), whereas CLA content had an inverse behavior, showing S1 (0.67%) and S2 (0.64%) higher concentrations than S3 (0.55%) and S4 (0.28%) (P<0.05). Diet based on pastures plus a low level of supplementation produced meat with better nutritional characteristics than other productive alternatives, without significant effects of the biotypes. PMID:22062907

  9. Aeromonas hydrophila and its relation with drinking water indicators of microbiological quality in Argentine.

    PubMed

    Fernández, M C; Giampaolo, B N; Ibañez, S B; Guagliardo, M V; Esnaola, M M; Conca, L; Valdivia, P; Stagnaro, S M; Chiale, C; Frade, H

    2000-01-01

    In Argentine, water municipal supplies disinfection is carried out by chlorine. We have isolated Aeromonas hydrophila from a chlorinated water supply in Buenos Aires that fulfilled Argentinean microbiological quality standards. It is an aquatic organism that could produce cytotoxins and enterotoxins associated with acute gastroenteritis and wound infections in human and hemorrhagic septicaemia of fish, reptiles and amphibians. The isolated strain produced protein bands at isoelectric point in the range of 4.6-5.3 lightly labile at 56 degrees C and heat labile at 100 degrees C non cholera antitoxin reactive in electrofocusing assay (IEF) and showed hemolytic activity thermolabile at 56 degrees C and 100 degrees C in 5% rabbit erythrocytes in phosphate buffered saline. A cytotoxic effect thermolabile at 56 degrees C and 100 degrees C and a cytotonic activity were demonstrated in Vero cell cultures. Survival assay of A. hydrophila and indicator organisms would show no correlation between their contamination sources. Biofilms production could explain the persistence of this gram negative pathogen organism in chlorinated tap water. A water system supply maintenance program and pasteurisation may be performed in spite of water chlorination.

  10. Linking nutrition and behavioural dominance: carbohydrate scarcity limits aggression and activity in Argentine ants.

    PubMed

    Grover, Crystal D; Kay, Adam D; Monson, Jessica A; Marsh, Thomas C; Holway, David A

    2007-12-01

    Predicting the outcome of competitive interactions is a fundamental goal in ecology. Ecological stoichiometry, which relates nutrient balance to ecological processes, provides a framework for identifying mechanistic links among macronutrient availability, nutritional physiology and competitive performance. Because carbohydrates serve as a principal metabolic fuel, carbohydrate scarcity may impinge upon behaviours affecting competitive dominance (e.g. aggression, activity) to a greater extent than deficiencies of protein or other nutrients used preferentially for growth. Here, we tested this prediction with a diet manipulation study involving laboratory colonies of Argentine ants (Linepithema humile), a widespread and aggressive invasive species. The availability of both sucrose and insect prey influenced brood production and worker survival after three months. However, colonies became less aggressive and less active only when deprived of sucrose (but not prey). Scarcity of sucrose (but not prey) was also associated with reduced fat mass in individual workers. These data provide the first experimental support that carbohydrate scarcity compromises aggression and activity in ants, and illustrate, in principle, how access to carbohydrate-rich resources (e.g. plant exudates, hemipteran honeydew) might influence behavioural investments that contribute to competitive performance. Such investments might be especially important for invasive ants, given their aggressiveness and tendency to interact with honeydew-producing Hemiptera.

  11. Model for cradle-to-gate life cycle assessment of clinker production

    SciTech Connect

    Michael Elias Boesch; Annette Koehler; Stefanie Hellweg

    2009-10-01

    A model for input- and technology-dependent cradle-to-gate life cycle assessments (LCA) was constructed to quantify emissions and resource consumption of various clinker production options. The model was compiled using data of more than 100 clinker production lines and complemented with literature data and best judgment from experts. It can be applied by the cement industry for the selection of alternative fuels and raw materials (AFR) and by authorities for decision-support regarding the permission of waste co-processing in cement kilns. In the field of sustainable construction, the model can be used to compare clinker production options. Two case studies are presented. First, co-processing of four different types of waste is analyzed at a modern precalciner kiln system. Second, clinker production is compared between five kiln systems. Results show that the use of waste (tires, prepared industrial waste, dried sewage sludge, blast furnace slag) led to reduced greenhouse gas emissions, decreased resource consumption, and mostly to reduced aggregated environmental impacts. Regarding the different kiln systems, the environmental impact generally increased with decreasing energy efficiency. 35 refs., 2 figs., 2 tabs.

  12. Tools and Strategies for Product Life Cycle Management ñ A Case Study in Foundry

    NASA Astrophysics Data System (ADS)

    Patil, Rajashekar; Kumar, S. Mohan; Abhilash, E.

    2012-08-01

    Advances in information and communication technology (ICT) have opened new possibilities of collaborations among the customers, suppliers, manufactures and partners to effectively tackle various business challenges. Product Life Cycle Management(PLM) has been a proven approach for Original Equipment Manufacturers (OEMs) to increase their productivity, improve their product quality, speed up delivery, and increase their profit and to become more efficient. However, their Tier 2 and Tier 3 suppliers like foundry industries are still in their infancy without adopting PLM. Hence to enhance their understanding, the basic concepts, the tools and strategies for PLM are presented is this paper. By selecting and implementing appropriate PLM strategies in a small foundry, an attempt was also made to understand the immediate benefits of using PLM tools (commercial PLM software and digital manufacturing tools). This study indicated a reduction in lead time and improved utilization of organizational resources in the production of automobile impeller. These observations may be further extrapolated to other multiproduct, multi-discipline and multi-customer companies to realize the advantages of using PLM technology

  13. Life-cycle assessment of the beef cattle production system for the northern great plains, USA.

    PubMed

    Lupo, Christopher D; Clay, David E; Benning, Jennifer L; Stone, James J

    2013-09-01

    A life-cycle assessment (LCA) model was developed to estimate the environmental impacts associated with four different U.S. Northern Great Plains (NPG) beef production systems. The LCA model followed a "cradle-to-gate" approach and incorporated all major unit processes, including mineral supplement production. Four distinct operation scenarios were modeled based on production strategies common to the NGP, and a variety of impacts were determined. The scenarios include a normal operation, early weaning of the calf, fast-tack backgrounding, and grassfed. Enteric emissions and manure emissions and handling were consistently the largest contributors to the LCA impacts. There was little variability between production scenarios except for the grassfed, where the greenhouse gas (GHG) emissions were 37% higher due to a longer finishing time and lower finishing weight. However, reductions to GHG emissions (15-24%) were realized when soil organic carbon accrual was considered and may be a more realistic estimate for the NGP. Manure emissions and handing were primary contributors to potential eutrophication and acidification impacts. Mitigation strategies to reduce LCA impacts, including diet manipulation and management strategies (i.e., treatment of manure), were considered from a whole-systems perspective. Model results can be used for guidance by NGP producers, environmental practitioners, and policymakers. PMID:24216416

  14. Thermodynamic Analysis of Isothermal Redox Cycling of Ceria for Solar Fuel Production

    SciTech Connect

    Bader, R; Venstrom, LJ; Davidson, JH; Lipinski, W

    2013-09-01

    A thermodynamic analysis of continuous fuel production by redox cycling of ceria in a single solar reactor under isothermal conditions is presented. Ceria is partially reduced in a sweep gas flow of purified nitrogen and reoxidized with either steam or carbon dioxide to produce hydrogen or carbon monoxide, respectively. The sweep gas and oxidizer flows are preheated by the product gases. The influence of selected process parameters, including operating temperature, pressure, and the effectiveness of heat recovery, on the solar-to-fuel conversion efficiency is determined. For a solar concentration ratio of 3000, typical of state-of-the-art solar dish concentrators, and operating temperature of 1773 K, 95.5% of the available gas-phase heat must be recovered to reach conversion efficiencies of 10% and 18% for hydrogen and carbon monoxide production, respectively, assuming the flow rate of inert sweep gas is equivalent to that in a counter-current flow arrangement of gas and ceria. The efficiency depends strongly on the gas-phase heat recovery effectiveness and the sweep gas flow rate. Introducing a temperature swing of 150 K between reduction and oxidation steps strongly reduces the sweep gas flow rate and increases the efficiency from 10% to 31.6% for hydrogen production.

  15. The Development of Terrestrial Water Cycle Applications for SMAP Soil Moisture Data Products

    NASA Astrophysics Data System (ADS)

    Crow, W.; Ryu, D.

    2008-12-01

    Soil moisture storage sits at the locus of the terrestrial water cycle and governs the relative partitioning of precipitation into various land surface flux components. Consequently, improved observational constraint of soil moisture variations should improve our ability to globally monitor the terrestrial water cycle. However, to date, most evidence for such enhancement has been based on synthetic studies and not actual data. The maturity of existing soil moisture datasets (from e.g. the NASA/JAXA AMRS-E and TMI satellite sensors) provides an opportunity to better describe this potential prior to the anticipated launch of the NASA SMAP mission. Using existing remotely-sensed soil moisture datasets, the presentation will demonstrate the potential for improving satellite-based rainfall accumulation products over land and describe a novel data assimilation strategy for leveraging improved rainfall products to enhance global runoff modeling. Despite well-known shortcomings in existing satellite soil moisture data sets (e.g. limited accuracy over vegetation and shallow vertical measurement depths), these strategies lead to measurable improvements in rainfall and runoff estimates over a large fraction of global continental areas. Realized benefits are most profound in lightly-vegetated areas amenable to satellite estimation of surface soil moisture and data-poor land areas lacking adequate ground-based instrumentation. The ability to enhance precipitation also allows for dual data assimilation strategies in which remotely-sensed soil moisture is used to simultaneously correct both the representation of antecedent soil moisture in a hydrologic model and the precipitation forcing applied to the model. Prospects for applying such a dual assimilation approach to data poor areas of Africa will be examined as will potential enhancements associated with the improved accuracy and resolution of SMAP soil moisture products relative to existing datasets.

  16. Fragile-X mental retardation: molecular diagnosis in Argentine patients.

    PubMed

    Florencia, Giliberto; Irene, Szijan; Veronica, Ferreiro

    2006-11-30

    Fragile-X-syndrome (FXS) is the most common type of inherited cognitive impairment. The underlying molecular alteration consists of a CGG-repeat amplification within the FMR-1 gene. The phenotype is only apparent once a threshold in the number of repeats has been exceeded (full mutation). The aim of this study was to characterize the FMR-1 CGG-repeat status in Argentine patients exhibiting mental retardation. A total of 330 blood samples from patients were analyzed by PCR and Southern blot analysis. Initially, DNA from 78 affected individuals were studied by PCR. Since this method is unable to detect high molecular weight alleles, however, we undertook a second approach using the Southern blotting technique to analyze the CGG repeat number and methylation status. Southern blot analysis showed an altered pattern in 14 out of 240 (6%) unrelated patients, with half of them presenting a mosaic pattern. Eight out of 17 families (47%) showed a (suggest deleting highlight). The characteristic FXS pattern was identified in 8/17 families (47%), and in 4 of these families 25% of the individuals presented with a mosaic model. The expansion from pre-mutation to full mutation was shown to occur both at the pre and post zygotic levels. The detection of FXS mutations has allowed us to offer more informed genetic counseling, prenatal diagnosis and reliable patient follow-up.

  17. Antibiotic sensitivity of an Argentine strain collection of Moraxella bovis.

    PubMed

    Zielinski, G; Piscitelli, H; Perez-Monti, H; Stobbs, L A

    2000-01-01

    The antimicrobial susceptibility of 88 isolates of Moraxella bovis of Argentine origin was evaluated for 12 antimicrobials by broth microdilution procedures. The isolates had a minimum inhibitory concentration (MIC90) of < or = 0.06 microg/mL to enrofloxacin; < or = 0.12 microg/mL to ceftiofur; < or = 0.25 microg/mL to ampicillin; < or = 0.5 microg/mL to florfenicol and gentamicin; < or = 1.0 microg/mL to tilmicosin, erythromycin, and oxytetracycline; < or = 4.0 microg/mL to tylosin; < or = 8.0 microg/mL to spectinomycin; < or = 0.25/4.75 microg/mL to trimethoprim/sulfamethoxazole; and > or = 32 microg/mL to lincomycin. Modal MIC values for these antimicrobials were as follows: enrofloxacin, 0.03 microg/mL; ceftiofur, 0.06 pg/mL; ampicillin, 0.25 microg/mL; florfenicol, gentamicin, erythromycin, and oxytetracycline, 0.5 microg/mL; tilmicosin, 1.0 microg/mL; tylosin and spectinomycin, 4.0 microg/mL; lincomycin and erythromycin, 16 microg/mL; and trimethoprim/ sulfamethoxazole, < or = 0.25/4.75 microg/mL. These data show that all antimicrobials except lincomycin have MICs suggestive of sensitivity in vitro, though confirmation of clinical efficacy can only be properly assessed based on pharmacologic and/or clinical data to support the MIC values. PMID:19757583

  18. Insecticide Transfer Efficiency and Lethal Load in Argentine Ants

    DOE PAGES

    Hooper-Bui, L. M.; Kwok, E S.C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.

    2015-07-03

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), butmore » dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). Moreover, the distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. The bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.« less

  19. Insecticide Transfer Efficiency and Lethal Load in Argentine Ants

    SciTech Connect

    Hooper-Bui, L. M.; Kwok, E S.C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.

    2015-07-03

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). Moreover, the distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. The bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  20. [Distribution of Lutzomyia longipalpis in the Argentine Mesopotamia, 2010].

    PubMed

    Salomon, Oscar D; Fernandez, Maria S; Santini, María S; Saavedra, Silvina; Montiel, Natalia; Ramos, Marina A; Rosa, Juan R; Szelag, Enrique A; Martinez, Mariela F

    2011-01-01

    The first case of visceral leishmaniasis (VL) in Argentina was reported in 2006 in Posadas, Misiones. During the summer 2008-2009 Lutzomyia longipalpis, the VL vector, and canine VL cases were already spread along the province of Corrientes. In order to know the distribution of VL risk, systematic captures of the vector were performed between February and March 2010, in 18 areas of the provinces of Entre Ríos and Corrientes, and the city of Puerto Iguazú, Misiones, with a total of 313 traps/night. We confirmed the presence of Lu. longipalpis, for the first time in Chajarí (Entre Ríos), Alvear, La Cruz, Curuzú Cuatiá and Bella Vista (Corrientes), and Puerto Iguazú (Misiones). In Santo Tome and Monte Caseros (Corrientes), where the vector had been previously reported, traps with more samples were obtained with 830 and 126 Lu. Longipalpis trap/site/night respectively. These results show that the vector of urban VL continues spreading in the Argentine territory. Simultaneously, the spread of the parasite and the resulting human VL cases are associated with the dispersion of reservoirs, infected dogs, with or without clinical symptoms or signs, due to human transit. PMID:21296716

  1. Argentine ant trail pheromone disruption is mediated by trail concentration.

    PubMed

    Suckling, David Maxwell; Stringer, Lloyd D; Corn, Joshua E

    2011-10-01

    Argentine ant trail pheromone disruption, using continuous release of the trail pheromone compound (Z)-9-hexadecanal, reduces the incidence of trails and foraging rates of field populations. However, little is known about the concentrations of pheromone required for successful disruption. We hypothesized that higher pheromone quantities would be necessary to disrupt larger ant populations. To test this, we laid a 30-cm long base trail of (Z)-9-hexadecanal on a glass surface at low and high rates (1 and 100 pg/cm) (Trail 1), and laid a second, shorter trail (Trail 2, 10 cm long, located 1.5 cm upwind) near the middle of Trail 1 at six rates (1, 10, 100, 1,000, 10,000, and 100,000 pg/cm). We then recorded and digitized movements of individual ants following Trail 1, and derived a regression statistic, r (2), as an index of trail integrity, and also recorded arrival success at the other end of the trail (30 cm) near a food supply. Disruption of trails required 100 fold more pheromone upwind, independent of base-trail concentration. This implies that in the field, trail disruption is likely to be less successful against high ant-trail densities (greater concentration of trail pheromone), and more successful against newly formed or weak trails, as could be expected along invasion fronts. PMID:21964852

  2. Feeding strategy and cannibalism of the Argentine hake Merluccius hubbsi.

    PubMed

    Ocampo Reinaldo, M; González, R; Romero, M A

    2011-12-01

    The diet composition and feeding strategy of the Argentine hake Merluccius hubbsi in the San Matías Gulf were analysed in order to use this information for the sustainable management of the fishery. Merluccius hubbsi behaved as an opportunistic predator. Small M. hubbsi consumed planktonic crustaceans, whereas medium and large fish ate numerous prey taxa with low frequency of occurrence and variable specific abundance. Intra- and intercohort cannibalism were detected in all size groups and were particularly significant in large M. hubbsi. Medium-sized M. hubbsi consumed small conspecifics and large-sized M. hubbsi consumed both small and medium M. hubbsi. These results indicate that the removal of large M. hubbsi by fishing may increase the risk of overfishing by two combined effects: a direct effect of recruitment-overfishing and an indirect effect of growth-overfishing through an enhanced cannibalism of medium M. hubbsi on small M. hubbsi. Intra- and intercohort cannibalism and other trophic relationships in the M. hubbsi should therefore be considered explicitly in stock assessment models.

  3. Clinical and epidemiological patterns of Argentine haemorrhagic fever

    PubMed Central

    Maiztegui, J. I.

    1975-01-01

    The epidemiology of Argentine haemorrhagic fever (AHF) is closely related to cricetine rodents acting as natural hosts of Junin virus. The endemo-epidemic area, which has increased 5 times since the disease was first recognized 15-20 years ago, is located in a densely populated region of Argentina. It has been shown that the virus of LCM is active in humans and rodents of the AHF endemic area; this demonstrates the simultaneous presence of two arenaviruses pathogenic for man in a given geographic location. The disease is characterized by haematological, renal, neurological and cardiovascular changes. Electron microscopy and immunohistochemical studies have shown cytopathic changes, characteristic intracellular virus-like particles, and antigenic determinants of Junin virus in different organs from 9 cases of AHF. No deposits of immunoglobulins or C3 were found in the kidneys; in addition, an absence of fibrinogen and C3 in the hepatocytes and of immunoglobulins in the spleen was observed. These findings suggest a direct viral pathogenic action in the human disease. Ultrastructural and immunofluorescence studies in tissues of guinea-pigs inoculated with two strains of Junin virus revealed the presence of the same types of virus-like particles and antigenic determinants of Junin virus as were encountered in the human subjects with AHF. ImagesFig. 2Fig. 3 PMID:1085212

  4. SLR and GPS spatial techniques in ITRF. Argentine results.

    NASA Astrophysics Data System (ADS)

    Actis, Eloy Vicente; Huang, Dongping; Márquez, Raúl; Adarvez, Sonia; Flores, Matías; Brizuela, Diego; Nievas, Jesica; Podestá, Ricardo; Pacheco, Ana M.; Rojas, Hernán Alvis; Yin, Zhiqiang; Li, Jinzeng; Han, Yanben; Liu, Weidong; Wang, Rui

    2012-08-01

    Along the late 30 years spatial geodetic techniques enable us to measure horizontal and vertical deformations of the Earth’s surface with a very high precision. Performing this task we made Satellite Laser Ranging (SLR), and Global Positioning System (GPS) observations in South America ILRS 7406 Station placed at Observatorio Astronómico Félix Aguilar (OAFA) in San Juan, Argentina, accomplishing a Cooperation Agreement between CAS - NAOC and OAFA - UNSJ. Trough LAGEOS II Satellite observations we obtain rectangular coordinates of San Juan ILRS Station in the Terrestrial Reference Frame (ITR 2000), standing out that Argentine Station data were included in the late arrangements ITRF given by International Earth Rotation and Reference System Service (IERS). Spatial and temporary variations of the epoch 2010 - 2011 were evaluated finding out remarkable displacements, of about a half meter, related with seismic events on the region. We confirm these deformations by means of GP S determinations referred to Permanent GPS Station placed nearby the SLR Station.

  5. Insecticide transfer efficiency and lethal load in Argentine ants

    NASA Astrophysics Data System (ADS)

    Hooper-Bui, L. M.; Kwok, E. S. C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.

    2015-10-01

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  6. Biogeochemical Cycling

    NASA Technical Reports Server (NTRS)

    Bebout, Brad; Fonda, Mark (Technical Monitor)

    2002-01-01

    This lecture will introduce the concept of biogeochemical cycling. The roles of microbes in the cycling of nutrients, production and consumption of trace gases, and mineralization will be briefly introduced.

  7. Secondary organic aerosol production from diesel vehicle exhaust: impact of aftertreatment, fuel chemistry and driving cycle

    NASA Astrophysics Data System (ADS)

    Gordon, T. D.; Presto, A. A.; Nguyen, N. T.; Robertson, W. H.; Na, K.; Sahay, K. N.; Zhang, M.; Maddox, C.; Rieger, P.; Chattopadhyay, S.; Maldonado, H.; Maricq, M. M.; Robinson, A. L.

    2014-05-01

    Environmental chamber ("smog chamber") experiments were conducted to investigate secondary organic aerosol (SOA) production from dilute emissions from two medium-duty diesel vehicles (MDDVs) and three heavy-duty diesel vehicles (HDDVs) under urban-like conditions. Some of the vehicles were equipped with emission control aftertreatment devices, including diesel particulate filters (DPFs), selective catalytic reduction (SCR) and diesel oxidation catalysts (DOCs). Experiments were also performed with different fuels (100% biodiesel and low-, medium- or high-aromatic ultralow sulfur diesel) and driving cycles (Unified Cycle,~Urban Dynamometer Driving Schedule, and creep + idle). During normal operation, vehicles with a catalyzed DPF emitted very little primary particulate matter (PM). Furthermore, photooxidation of dilute emissions from these vehicles produced essentially no SOA (below detection limit). However, significant primary PM emissions and SOA production were measured during active DPF regeneration experiments. Nevertheless, under reasonable assumptions about DPF regeneration frequency, the contribution of regeneration emissions to the total vehicle emissions is negligible, reducing PM trapping efficiency by less than 2%. Therefore, catalyzed DPFs appear to be very effective in reducing both primary PM emissions and SOA production from diesel vehicles. For both MDDVs and HDDVs without aftertreatment substantial SOA formed in the smog chamber - with the emissions from some vehicles generating twice as much SOA as primary organic aerosol after 3 h of oxidation at typical urban VOC / NOx ratios (3 : 1). Comprehensive organic gas speciation was performed on these emissions, but less than half of the measured SOA could be explained by traditional (speciated) SOA precursors. The remainder presumably originates from the large fraction (~30%) of the nonmethane organic gas emissions that could not be speciated using traditional one-dimensional gas chromatography. The

  8. Productivity Estimation of Hypersaline Microbial Mat Communities - Diurnal Cycles of Dissolved Oxygen

    NASA Astrophysics Data System (ADS)

    Less, G.; Cohen, Y.; Luz, B.; Lazar, B.

    2002-05-01

    Hypersaline microbial mat communities (MMC) are the modern equivalents of the Archean stromatolities, the first photosynthetic organisms on Earth. An estimate of their oxygen production rate is important to the understanding of oxygen evolution on Earth ca. 2 b.y.b.p. Here we use the diurnal cycle of dissolved oxygen, O2/Ar ratio and the isotopic composition of dissolved oxygen to calculate net and gross primary productivity of MMC growing in a large scale (80 m2) experimental pan. The pan is inoculated with MMC taken from the Solar Lake, Sinai, Egypt and filled with 90\\permil evaporated Red Sea water brine up to a depth of ca. 0.25 m. It is equipped with computerized flow through system that is programmed to pump pan water at selected time intervals into a sampling cell fitted with dissolved oxygen, pH, conductivity and temperature sensors connected to a datalogger. Manual brine samples were taken for calibrating the sensors, mass spectrometric analyses and for measurements of additional relevant parameters. Dissolved oxygen concentrations fluctuate during the diurnal cycle being highly supersaturated except for the end of the night. The O2 curve varies seasonally and has a typical "shark fin" shape due to the MMC metabolic response to the shape of the diurnal light curve. The dissolved oxygen data were fitted to a smooth curve that its time derivative (dO2 /dt) is defined as: Z dO2 /dt=GP-R-k(O2(meas)- O2(sat)) where z is the depth (m); GP and R are the MMC gross production and respiration (mol m-2 d-1), respectively; k is the gas exchange coefficient (m d-1); O2(meas) and O2(sat) (mol L-1) are the measured and equilibrium dissolved oxygen concentrations, respectively. The high resolution sampling of the automated system produces O2 curves that enable the calculation of smooth and reliable time derivatives. The calculations yield net production values that vary between 1,000 10-6 to -100 10-6 mol O2 m-2 h-1 and day respiration rates between 60 10-6 to 30 10

  9. Environmental and economic analysis of end of life management options for an HDPE product using a life cycle thinking approach.

    PubMed

    Simões, Carla L; Pinto, Lígia M Costa; Bernardo, C A

    2014-05-01

    Manufacturers have been increasingly considering the implication of materials used in commercial products and the management of such products at the end of their useful lives (as waste or as post-consumer secondary materials). The present work describes the application of the life cycle thinking approach to a plastic product, specifically an anti-glare lamellae (used for road safety applications) made with high-density polyethylene (HDPE). This study shows that optimal environmental and economic outcomes associated with this product can be realized by recovering the material at the end of its useful life (end of life, EoL) and by using the recycled HDPE as a raw material in the production of new similar products. The study confirmed the applicability of the life cycle thinking approach by industry in sustainable products development, supporting the development of robust environmental and economic guidelines. PMID:24692456

  10. Environmental and economic analysis of end of life management options for an HDPE product using a life cycle thinking approach.

    PubMed

    Simões, Carla L; Pinto, Lígia M Costa; Bernardo, C A

    2014-05-01

    Manufacturers have been increasingly considering the implication of materials used in commercial products and the management of such products at the end of their useful lives (as waste or as post-consumer secondary materials). The present work describes the application of the life cycle thinking approach to a plastic product, specifically an anti-glare lamellae (used for road safety applications) made with high-density polyethylene (HDPE). This study shows that optimal environmental and economic outcomes associated with this product can be realized by recovering the material at the end of its useful life (end of life, EoL) and by using the recycled HDPE as a raw material in the production of new similar products. The study confirmed the applicability of the life cycle thinking approach by industry in sustainable products development, supporting the development of robust environmental and economic guidelines.

  11. Life cycle assessment of the production and use of polypropylene tree shelters.

    PubMed

    Arnold, J C; Alston, S M

    2012-02-01

    A detailed Life Cycle Assessment (LCA) has been conducted for the manufacture, use and disposal of polypropylene tree shelters, which are used to protect young seedlings in the first few years of growth. The LCA was conducted using Simapro software, the Ecoinvent database and ReCiPe assessment methodology. Detailed information on materials, manufacturing, packaging and distribution of shelters was obtained from Tubex Ltd. in South Wales, UK. Various scenarios based on different forest establishment methods, with or without tree shelters were derived and analysed using data from published literature and independent sources. The scenarios included commercial forestry in northern temperate conditions, amenity forest establishment in temperate conditions, and forest establishment in semi-arid conditions. For commercial forestry, a reduction in required seedling production and planting as well as additional time-averaged wood production led to significant benefits with tree shelters, both compared to unprotected and fenced cases. For the amenity forest scenarios, tree shelter use had a net environmental impact, while for semi-arid forestry, the benefits of reduction in water use outweighed shelter production impacts. The current practice of in-situ degradation was compared to collection and disposal and it was found that in-situ degradation was slightly preferable in terms of overall environmental impact. Use of biopolymer-based shelters would improve the environmental performance slightly. PMID:22098783

  12. Comparison of Asian Aquaculture Products by Use of Statistically Supported Life Cycle Assessment.

    PubMed

    Henriksson, Patrik J G; Rico, Andreu; Zhang, Wenbo; Ahmad-Al-Nahid, Sk; Newton, Richard; Phan, Lam T; Zhang, Zongfeng; Jaithiang, Jintana; Dao, Hai M; Phu, Tran M; Little, David C; Murray, Francis J; Satapornvanit, Kriengkrai; Liu, Liping; Liu, Qigen; Haque, M Mahfujul; Kruijssen, Froukje; de Snoo, Geert R; Heijungs, Reinout; van Bodegom, Peter M; Guinée, Jeroen B

    2015-12-15

    We investigated aquaculture production of Asian tiger shrimp, whiteleg shrimp, giant river prawn, tilapia, and pangasius catfish in Bangladesh, China, Thailand, and Vietnam by using life cycle assessments (LCAs), with the purpose of evaluating the comparative eco-efficiency of producing different aquatic food products. Our starting hypothesis was that different production systems are associated with significantly different environmental impacts, as the production of these aquatic species differs in intensity and management practices. In order to test this hypothesis, we estimated each system's global warming, eutrophication, and freshwater ecotoxicity impacts. The contribution to these impacts and the overall dispersions relative to results were propagated by Monte Carlo simulations and dependent sampling. Paired testing showed significant (p < 0.05) differences between the median impacts of most production systems in the intraspecies comparisons, even after a Bonferroni correction. For the full distributions instead of only the median, only for Asian tiger shrimp did more than 95% of the propagated Monte Carlo results favor certain farming systems. The major environmental hot-spots driving the differences in environmental performance among systems were fishmeal from mixed fisheries for global warming, pond runoff and sediment discards for eutrophication, and agricultural pesticides, metals, benzalkonium chloride, and other chlorine-releasing compounds for freshwater ecotoxicity. The Asian aquaculture industry should therefore strive toward farming systems relying upon pelleted species-specific feeds, where the fishmeal inclusion is limited and sourced sustainably. Also, excessive nutrients should be recycled in integrated organic agriculture together with efficient aeration solutions powered by renewable energy sources. PMID:26512735

  13. Floodplain Vegetation Productivity and Carbon Cycle Dynamics of the Middle Fork Flathead River of Northwest Montana

    NASA Astrophysics Data System (ADS)

    Oakins, A. J.; Kimball, J. S.; Relyea, S.; Stanford, J. A.

    2005-05-01

    River floodplains are vital natural features that store floodwaters, improve water quality, provide habitat, and create recreational opportunities. Recent studies have shown that strong interactions among flooding, channel and sediment movement, vegetation, and groundwater create a dynamic shifting habitat mosaic that promotes biodiversity and complex food webs. Multiple physical and environmental processes interact within these systems to influence forest productivity, including water availability, nutrient supply, soil texture, and disturbance history. This study is designed to quantify the role of groundwater depth and meteorology in determining spatial and temporal patterns of net primary productivity (NPP) within the Nyack floodplain of the Middle Fork Flathead River, Northwestern Montana. We examine three intensive field sites composed of mature, mixed deciduous and evergreen conifer forest with varying hydrologic and vegetative characteristics. We use a modified Biome-BGC ecosystem process model with field-collected data (LAI, increment growth cores, groundwater depth, vegetation sap-flow, and local meteorology) to describe the effects of floodplain groundwater dynamics on vegetation community structure, and carbon/nitrogen cycling. Initial results indicate that conifers are more sensitive than deeper-rooted deciduous species to variability in groundwater depth and meteorological conditions. Forest productivity also shows a non-linear response to groundwater depth. Sites with intermediate groundwater depths (0.2-0.5m) allow vegetation to maintain connectivity to groundwater over longer periods during the growing season, are effectively uncoupled from atmospheric constraints on photosynthesis, and generally have greater productivity. Shallow groundwater sites (<0.2m) are less productive due to the indirect effects of reduced soil aerobic decomposition and reduced plant available nitrogen.

  14. Life cycle analysis within pharmaceutical process optimization and intensification: case study of active pharmaceutical ingredient production.

    PubMed

    Ott, Denise; Kralisch, Dana; Denčić, Ivana; Hessel, Volker; Laribi, Yosra; Perrichon, Philippe D; Berguerand, Charline; Kiwi-Minsker, Lioubov; Loeb, Patrick

    2014-12-01

    As the demand for new drugs is rising, the pharmaceutical industry faces the quest of shortening development time, and thus, reducing the time to market. Environmental aspects typically still play a minor role within the early phase of process development. Nevertheless, it is highly promising to rethink, redesign, and optimize process strategies as early as possible in active pharmaceutical ingredient (API) process development, rather than later at the stage of already established processes. The study presented herein deals with a holistic life-cycle-based process optimization and intensification of a pharmaceutical production process targeting a low-volume, high-value API. Striving for process intensification by transfer from batch to continuous processing, as well as an alternative catalytic system, different process options are evaluated with regard to their environmental impact to identify bottlenecks and improvement potentials for further process development activities.

  15. Tap-Hole Life Cycle Design Criteria: A Case Study Based on Silicomanganese Production

    NASA Astrophysics Data System (ADS)

    Steenkamp, J. D.; Sutherland, J. J.; Hayman, D. A.; Muller, J.

    2016-06-01

    Managing the tapping of furnaces is a challenge to most furnace operators. As a hole is made in the refractory lining and re-filled with clay, several times a day, the tap-hole is one of the weak spots in the refractory lining. Tap-hole failures are high-risk events, and steps should be taken to minimize the risks. Designing for the life-cycle of the tap-hole is proposed and discussed as a way of minimizing the risks associated with tap-hole failure. Design criteria are proposed not only for a total reline and normal operation but also for emergency conditions, as well as maintenance, and repair of the tap-hole. The criteria are discussed in the context of silicomanganese production in South Africa.

  16. Microalgae Production from Power Plant Flue Gas: Environmental Implications on a Life Cycle Basis

    SciTech Connect

    Kadam, K. L.

    2001-06-22

    Power-plant flue gas can serve as a source of CO{sub 2} for microalgae cultivation, and the algae can be cofired with coal. This life cycle assessment (LCA) compared the environmental impacts of electricity production via coal firing versus coal/algae cofiring. The LCA results demonstrated lower net values for the algae cofiring scenario for the following using the direct injection process (in which the flue gas is directly transported to the algae ponds): SOx, NOx, particulates, carbon dioxide, methane, and fossil energy consumption. Carbon monoxide, hydrocarbons emissions were statistically unchanged. Lower values for the algae cofiring scenario, when compared to the burning scenario, were observed for greenhouse potential and air acidification potential. However, impact assessment for depletion of natural resources and eutrophication potential showed much higher values. This LCA gives us an overall picture of impacts across different environmental boundaries, and hence, can help in the decision-making process for implementation of the algae scenario.

  17. Feeding behavior and social interactions of the Argentine ant Linepithema humile change with sucrose concentration.

    PubMed

    Sola, F J; Josens, R

    2016-08-01

    Liquid sugar baits are well accepted by the Argentine ant Linepithema humile and are suitable for the chemical control of this invasive species. We evaluated how sugar concentrations affect the foraging behavior of L. humile individuals. We quantified feeding variables for individual foragers (ingested load, feeding time and solution intake rate) when feeding on sucrose solutions of different concentrations, as well as post-feeding interactions with nestmates. Solutions of intermediate sucrose concentrations (10-30%) were the most consumed and had the highest intake rates, whereas solutions of high sucrose concentrations (60 and 70%) resulted in extended feeding times, low intake rates and ants having smaller crop loads. In terms of post-feeding interactions, individuals fed solutions of intermediate sucrose concentrations (20%) had the highest probability of conducting trophallaxis and the smallest latency to drop exposure (i.e. lowest time delay). Trophallaxis duration increased with increasing sucrose concentrations. Behavioral motor displays, including contacts with head jerking and walking with a gaster waggle, were lowest for individuals that ingested the more dilute sucrose solution (5%). These behaviors have been previously suggested to act as a communication channel for the activation and/or recruitment of nestmates. We show here that sucrose concentration affects feeding dynamics and modulates decision making related to individual behavior and social interactions of foragers. Our results indicate that intermediate sucrose concentrations (ca. 20%), appear to be most appropriate for toxic baits because they promote rapid foraging cycles, a high crop load per individual, and a high degree of stimulation for recruitment.

  18. Feeding behavior and social interactions of the Argentine ant Linepithema humile change with sucrose concentration.

    PubMed

    Sola, F J; Josens, R

    2016-08-01

    Liquid sugar baits are well accepted by the Argentine ant Linepithema humile and are suitable for the chemical control of this invasive species. We evaluated how sugar concentrations affect the foraging behavior of L. humile individuals. We quantified feeding variables for individual foragers (ingested load, feeding time and solution intake rate) when feeding on sucrose solutions of different concentrations, as well as post-feeding interactions with nestmates. Solutions of intermediate sucrose concentrations (10-30%) were the most consumed and had the highest intake rates, whereas solutions of high sucrose concentrations (60 and 70%) resulted in extended feeding times, low intake rates and ants having smaller crop loads. In terms of post-feeding interactions, individuals fed solutions of intermediate sucrose concentrations (20%) had the highest probability of conducting trophallaxis and the smallest latency to drop exposure (i.e. lowest time delay). Trophallaxis duration increased with increasing sucrose concentrations. Behavioral motor displays, including contacts with head jerking and walking with a gaster waggle, were lowest for individuals that ingested the more dilute sucrose solution (5%). These behaviors have been previously suggested to act as a communication channel for the activation and/or recruitment of nestmates. We show here that sucrose concentration affects feeding dynamics and modulates decision making related to individual behavior and social interactions of foragers. Our results indicate that intermediate sucrose concentrations (ca. 20%), appear to be most appropriate for toxic baits because they promote rapid foraging cycles, a high crop load per individual, and a high degree of stimulation for recruitment. PMID:27063551

  19. An experimental study of competition between fire ants and Argentine ants in their native range.

    PubMed

    LeBrun, E G; Tillberg, C V; Suarez, A V; Folgarait, P J; Smith, C R; Holway, D A

    2007-01-01

    An understanding of why introduced species achieve ecological success in novel environments often requires information about the factors that limit the abundance of these taxa in their native ranges. Although numerous recent studies have evaluated the importance of natural enemies in this context, relatively few have examined how ecological success may result from differences in the magnitude of interference competition between communities in the native and introduced ranges of nonnative species. Here we examine how native-range competitive environments may relate to invasion success for two important invasive species, the red imported fire ant (Solenopsis invicta) and the Argentine ant (Linepithema humile), in a region of native-range sympatry. At two study sites in northern Argentina, we used stable-isotope analysis, a variety of observational approaches, and two different reciprocal removal experiments to test (1) whether S. invicta competes asymmetrically with L. humile (as suggested by the 20th century pattern of replacement in the southeastern United States) and (2) the extent to which these two species achieve behavioral and numerical dominance. Stable-isotope analysis and activity surveys indicated that S. invicta and L. humile are both omnivores and forage during broadly overlapping portions of the diel cycle. Short-term removal experiments at baits revealed no competitive asymmetry between S. invicta and L. humile. Longer-term colony removal experiments illustrated that S. invicta and L. humile experience an approximately equal competitive release upon removal of the other. Our results indicate that neither S. invicta nor L. humile achieves the same degree of behavioral or ecological dominance where they co-occur in native populations as they do in areas where either is common in their introduced range. These results strongly suggest that interspecific competition is an important limiting factor for both S. invicta and L. humile in South America.

  20. Conceptual design analysis for hybrid-cycle OTEC plants for co-production of electric power and desalinated water

    NASA Astrophysics Data System (ADS)

    Rabas, T.; Panchal, C. B.; Genens, L.

    Hybrid-cycle Ocean Thermal Energy Conversion (OTEC) power plants are shown to be potentially the most flexible and cost effective in obtaining any specific mix of electrical power and desalinated water. This paper describes two particular hybrid configurations. One achieves maximum power production and the other achieves maximum water production for a given cold sea-water flow rate and pipe size. When power is the desired commodity and desalinated water is the by-product, the most effective configuration is the conventional hybrid cycle. When only water production is required, the desired configuration combines a multistage flash evaporator and a closed-cycle power OTEC plant, the latter generates the power to run the support equipment with no net or minimal power generation.

  1. Faltering lemming cycles reduce productivity and population size of a migratory Arctic goose species.

    PubMed

    Nolet, Bart A; Bauer, Silke; Feige, Nicole; Kokorev, Yakov I; Popov, Igor Yu; Ebbinge, Barwolt S

    2013-07-01

    The huge changes in population sizes of Arctic-nesting geese offer a great opportunity to study population limitation in migratory animals. In geese, population limitation seems to have shifted from wintering to summering grounds. There, in the Arctic, climate is rapidly changing, and this may impact reproductive performance, and perhaps population size of geese, both directly (e.g. by changes in snow melt) or indirectly (e.g. by changes in trophic interactions). Dark-bellied brent geese (Branta bernicla bernicla L.) increased 20-fold since the 1950s. Its reproduction fluctuates strongly in concert with the 3-year lemming cycle. An earlier analysis, covering the growth period until 1988, did not find evidence for density dependence, but thereafter the population levelled off and even decreased. The question is whether this is caused by changes in lemming cycles, population density or other factors like carry-over effects. Breeding success was derived from proportions of juveniles. We used an information-theoretical approach to investigate which environmental factors best explained the variation in breeding success over nearly 50 years (1960-2008). We subsequently combined GLM predictions of breeding success with published survival estimates to project the population trajectory since 1991 (year of maximum population size). In this way, we separated the effects of lemming abundance and population density on population development. Breeding success was mainly dependent on lemming abundance, the onset of spring at the breeding grounds, and the population size of brent goose. No evidence was found for carry-over effects (i.e. effects of conditions at main spring staging site). Negative density dependence was operating at a population size above c. 200 000 individuals, but the levelling off of the population could be explained by faltering lemming cycles alone. Lemmings have long been known to affect population productivity of Arctic-nesting migratory birds and, more

  2. Faltering lemming cycles reduce productivity and population size of a migratory Arctic goose species

    PubMed Central

    Nolet, Bart A; Bauer, Silke; Feige, Nicole; Kokorev, Yakov I; Popov, Igor Yu; Ebbinge, Barwolt S

    2013-01-01

    1. The huge changes in population sizes of Arctic-nesting geese offer a great opportunity to study population limitation in migratory animals. In geese, population limitation seems to have shifted from wintering to summering grounds. There, in the Arctic, climate is rapidly changing, and this may impact reproductive performance, and perhaps population size of geese, both directly (e.g. by changes in snow melt) or indirectly (e.g. by changes in trophic interactions). 2. Dark-bellied brent geese (Branta bernicla bernicla L.) increased 20-fold since the 1950s. Its reproduction fluctuates strongly in concert with the 3-year lemming cycle. An earlier analysis, covering the growth period until 1988, did not find evidence for density dependence, but thereafter the population levelled off and even decreased. The question is whether this is caused by changes in lemming cycles, population density or other factors like carry-over effects. 3. Breeding success was derived from proportions of juveniles. We used an information-theoretical approach to investigate which environmental factors best explained the variation in breeding success over nearly 50 years (1960–2008). We subsequently combined GLM predictions of breeding success with published survival estimates to project the population trajectory since 1991 (year of maximum population size). In this way, we separated the effects of lemming abundance and population density on population development. 4. Breeding success was mainly dependent on lemming abundance, the onset of spring at the breeding grounds, and the population size of brent goose. No evidence was found for carry-over effects (i.e. effects of conditions at main spring staging site). Negative density dependence was operating at a population size above c. 200 000 individuals, but the levelling off of the population could be explained by faltering lemming cycles alone. 5. Lemmings have long been known to affect population productivity of Arctic-nesting migratory

  3. Faltering lemming cycles reduce productivity and population size of a migratory Arctic goose species.

    PubMed

    Nolet, Bart A; Bauer, Silke; Feige, Nicole; Kokorev, Yakov I; Popov, Igor Yu; Ebbinge, Barwolt S

    2013-07-01

    The huge changes in population sizes of Arctic-nesting geese offer a great opportunity to study population limitation in migratory animals. In geese, population limitation seems to have shifted from wintering to summering grounds. There, in the Arctic, climate is rapidly changing, and this may impact reproductive performance, and perhaps population size of geese, both directly (e.g. by changes in snow melt) or indirectly (e.g. by changes in trophic interactions). Dark-bellied brent geese (Branta bernicla bernicla L.) increased 20-fold since the 1950s. Its reproduction fluctuates strongly in concert with the 3-year lemming cycle. An earlier analysis, covering the growth period until 1988, did not find evidence for density dependence, but thereafter the population levelled off and even decreased. The question is whether this is caused by changes in lemming cycles, population density or other factors like carry-over effects. Breeding success was derived from proportions of juveniles. We used an information-theoretical approach to investigate which environmental factors best explained the variation in breeding success over nearly 50 years (1960-2008). We subsequently combined GLM predictions of breeding success with published survival estimates to project the population trajectory since 1991 (year of maximum population size). In this way, we separated the effects of lemming abundance and population density on population development. Breeding success was mainly dependent on lemming abundance, the onset of spring at the breeding grounds, and the population size of brent goose. No evidence was found for carry-over effects (i.e. effects of conditions at main spring staging site). Negative density dependence was operating at a population size above c. 200 000 individuals, but the levelling off of the population could be explained by faltering lemming cycles alone. Lemmings have long been known to affect population productivity of Arctic-nesting migratory birds and, more

  4. THE EFFECT OF ANOLYTE PRODUCT ACID CONCENTRATION ON HYBRID SULFUR CYCLE PERFORMANCE

    SciTech Connect

    Gorensek, M.; Summers, W.

    2010-03-24

    The Hybrid Sulfur (HyS) cycle (Fig. 1) is one of the simplest, all-fluids thermochemical cycles that has been devised for splitting water with a high-temperature nuclear or solar heat source. It was originally patented by Brecher and Wu in 1975 and extensively developed by Westinghouse in the late 1970s and early 1980s. As its name suggests, the only element used besides hydrogen and oxygen is sulfur, which is cycled between the +4 and +6 oxidation states. HyS comprises two steps. One is the thermochemical (>800 C) decomposition of sulfuric acid (H{sub 2}SO{sub 4}) to sulfur dioxide (SO{sub 2}), oxygen (O{sub 2}), and water. H{sub 2}SO{sub 4} = SO{sub 2} + 1/2 O{sub 2} + H{sub 2}O. The other is the SO{sub 2}-depolarized electrolysis of water to H{sub 2}SO{sub 4} and hydrogen (H{sub 2}), SO{sub 2} + 2 H{sub 2}O = H{sub 2}SO{sub 4} + H{sub 2}, E{sup o} = -0.156 V, explaining the 'hybrid' designation. These two steps taken together split water into H{sub 2} and O{sub 2} using heat and electricity. Researchers at the Savannah River National Laboratory (SRNL) and at the University of South Carolina (USC) have successfully demonstrated the use of proton exchange membrane (PEM) electrolyzers (Fig. 2) for the SO{sub 2}-depolarized electrolysis (sulfur oxidation) step, while Sandia National Laboratories (SNL) successfully demonstrated the high-temperature sulfuric acid decomposition (sulfur reduction) step using a bayonet-type reactor (Fig. 3). This latter work was performed as part of the Sulfur-Iodine (SI) cycle Integrated Laboratory Scale demonstration at General Atomics (GA). The combination of these two operations results in a simple process that will be more efficient and cost-effective for the massive production of hydrogen than alkaline electrolysis. Recent developments suggest that the use of PEMs other than Nafion will allow sulfuric acid to be produced at higher concentrations (>60 wt%), offering the possibility of net thermal efficiencies around 50% (HHV basis

  5. Using NASA Products of the Water Cycle for Improved Water Resources Management

    NASA Astrophysics Data System (ADS)

    Toll, D. L.; Doorn, B.; Engman, E. T.; Lawford, R. G.

    2010-12-01

    NASA Water Resources works within the Earth sciences and GEO community to leverage investments of space-based observation and modeling results including components of the hydrologic cycle into water resources management decision support tools for the goal towards the sustainable use of water. These Earth science hydrologic related observations and modeling products provide a huge volume of valuable data in both near-real-time and extended back nearly 50 years. Observations of this type enable assessment of numerous water resources management issues including water scarcity, extreme events of drought and floods, and water quality. Examples of water cycle estimates make towards the contributions to the water management community include snow cover and snowpack, soil moisture, evapotranspiration, precipitation, streamflow and ground water. The availability of water is also contingent on the quality of water and hence water quality is an important part of NASA Water Resources. Water quality activities include both nonpoint source (agriculture land use, ecosystem disturbances, impervious surfaces, etc.) and direct remote sensing ( i.e., turbidity, algae, aquatic vegetation, temperature, etc.). . The NASA Water Resources Program organizes its projects under five functional themes: 1) stream-flow and flood forecasting; 2) water consumptive use and irrigation (includes evapotranspiration); 3) drought; 4) water quality; and 5) climate impacts on water resources. Currently NASA Water Resources is supporting 21 funded projects with 11 additional projects being concluded. To maximize the use of NASA water cycle measurements end to projects are supported with strong links with decision support systems. The NASA Water Resources Program works closely with other government agencies NOAA, USDA-FAS, USGS, AFWA, USAID, universities, and non-profit, international, and private sector organizations. International water cycle applications include: 1) Famine Early Warning System Network

  6. Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean

    NASA Astrophysics Data System (ADS)

    Cavagna, A. J.; Fripiat, F.; Elskens, M.; Mangion, P.; Chirurgien, L.; Closset, I.; Lasbleiz, M.; Florez-Leiva, L.; Cardinal, D.; Leblanc, K.; Fernandez, C.; Lefèvre, D.; Oriol, L.; Blain, S.; Quéguiner, B.; Dehairs, F.

    2015-11-01

    Although the Southern Ocean is considered a high-nutrient, low-chlorophyll (HNLC) area, massive and recurrent blooms are observed over and downstream of the Kerguelen Plateau. This mosaic of blooms is triggered by a higher iron supply resulting from the interaction between the Antarctic Circumpolar Current and the local bathymetry. Net primary production, N uptake (NO3- and NH4+), and nitrification rates were measured at eight stations in austral spring 2011 (October-November) during the KEOPS 2 cruise in the Kerguelen Plateau area. Natural iron fertilization stimulated primary production, with mixed layer integrated net primary production and growth rates much higher in the fertilized areas (up to 315 mmol C m-2 d-1 and up to 0.31 d-1 respectively) compared to the HNLC reference site (12 mmol C m-2 d-1 and 0.06 d-1 respectively). Primary production was mainly sustained by nitrate uptake, with f ratios (corresponding to NO3--uptake / (NO3--uptake + NH4+-uptake)) lying at the upper end of the observations for the Southern Ocean (up to 0.9). We report high rates of nitrification (up to ~ 3 μmol N L-1 d-1, with ~ 90 % of them < 1 μmol N L-1 d-1) typically occurring below the euphotic zone, as classically observed in the global ocean. The specificity of the studied area is that at most of the stations, the euphotic layer was shallower than the mixed layer, implying that nitrifiers can efficiently compete with phytoplankton for the ammonium produced by remineralization at low-light intensities. Nitrate produced by nitrification in the mixed layer below the euphotic zone is easily supplied to the euphotic zone waters above, and nitrification sustained 70 ± 30 % of the nitrate uptake in the productive area above the Kerguelen Plateau. This complicates estimations of new production as potentially exportable production. We conclude that high productivity in deep mixing system stimulates the N cycle by increasing both assimilation and regeneration.

  7. Secondary organic aerosol production from diesel vehicle exhaust: impact of aftertreatment, fuel chemistry and driving cycle

    NASA Astrophysics Data System (ADS)

    Gordon, T. D.; Presto, A. A.; Nguyen, N. T.; Robertson, W. H.; Na, K.; Sahay, K. N.; Zhang, M.; Maddox, C.; Rieger, P.; Chattopadhyay, S.; Maldonado, H.; Maricq, M. M.; Robinson, A. L.

    2013-09-01

    Environmental chamber ("smog chamber") experiments were conducted to investigate secondary organic aerosol (SOA) production from dilute emissions from two medium-duty diesel vehicles (MDDVs) and three heavy-duty diesel vehicles (HDDVs) under urban-like conditions. Some of the vehicles were equipped with emission control aftertreatment devices including diesel particulate filters (DPF), selective catalytic reduction (SCR) and diesel oxidation catalysts (DOC). Experiments were also performed with different fuels (100% biodiesel and low-, medium- or high-aromatic ultralow sulfur diesel) and driving cycles (Unified Cycle, Urban Dynamometer Driving Schedule, and creep+idle). During normal operation, vehicles with a catalyzed DPF emitted very little primary particulate matter (PM). Furthermore, photo-oxidation of dilute emissions from these vehicles produced essentially no SOA (below detection limit). However, significant primary PM emissions and SOA production were measured during active DPF regeneration experiments. Nevertheless, under reasonable assumptions about DPF regeneration frequency, the contribution of regeneration emissions to the total vehicle emissions is negligible, reducing PM trapping efficiency by less than 2%. Therefore, catalyzed DPFs appear to be very effective in reducing both primary and secondary fine particulate matter from diesel vehicles. For both MDDVs and HDDVs without aftertreatment substantial SOA formed in the smog chamber - with the emissions from some vehicles generating twice as much SOA as primary organic aerosol after three hours of oxidation at typical urban VOC : NOx ratios (3:1). Comprehensive organic gas speciation was performed on these emissions, but less than half of the measured SOA could be explained by traditional (speciated) SOA precursors. The remainder presumably originates from the large fraction (~30%) of the non-methane organic gas emissions that could not be speciated using traditional one-dimensional gas

  8. Annual cycles of steroid hormone production, gonad development, and reproductive behavior in the Atlantic stingray.

    PubMed

    Tricas, T C; Maruska, K P; Rasmussen, L E

    2000-05-01

    The mating season of the Atlantic stingray (Dasyatis sabina), which begins in August and continues through April, is the longest documented for any elasmobranch fish. Despite this protracted mating period, female stingrays ovulate synchronously at the end of the mating season and there is no evidence for sperm storage by females. Thus, the proximate causal factors and ultimate function of this extended preovulatory mating are unknown. Annual cycles of the gonadal steroids testosterone (T), dihydrotestosterone (DHT), 17beta-estradiol (E2), and progesterone (P4) were measured for 26 months in a wild estuarine population of Atlantic stingrays to test for associations with their reproductive biology, gametogenesis, and sexual behavior. Serum androgen levels in males showed four phases within an annual cycle: (1) androgen suppression between reproductive seasons (April-July), (2) primary androgen increase during the onset of spermatocyte development (August-October), (3) androgen decrease following maximum testis growth and spermatocyte development (November-December), and (4) secondary androgen increase during the peak of sperm maturation (January-March). Increases in male E2 and P4 were correlated with spermatocyte/spermatocyst formation, maximum testis weight, and the primary (but not secondary) androgen surge. We propose that the production of male androgens across the full seven-month preovulatory mating period promotes their aggressive reproductive behavior and drives the protracted mating season of this species. In females, serum T and DHT showed relatively brief increases near ovulation, whereas E2 and P4 showed brief increases near both ovulation and parturition. The increase in female androgens near ovulation may increase female aggression when they are impregnable by courting males and enhance their choice of mates. This estuary sample population shows higher absolute steroid levels and distinct differences in temporal cycles compared to another Florida fresh

  9. Combined effect of hemipteran control and liquid bait on Argentine ant populations.

    PubMed

    Brightwell, R J; Bambara, S B; Silverman, J

    2010-10-01

    The invasive Argentine ant, Linepithema humile (Mayr), has become a worldwide problem capable of inflicting significant ecological and economic injury on urban, agricultural, and natural environments. The mobility of this pest ant has long been noted, rapidly moving nests to new food resources and then away as resources are depleted. This ant, like many pest ant species, has a special affinity for honeydew excreted by phloem-feeding Hemiptera. We investigated the effect of various hemipteran control strategies on terrapin scale densities and measured their indirect effect on local Argentine ant densities and foraging effort. We then determined whether this indirect treatment strategy improved the performance of an ant bait. We predicted that Argentine ants would move nests away from trees treated for Hemiptera and then move nests back when a liquid bait was offered, followed by a decline in ant numbers due to intake of the toxicant. A horticultural oil spray and soil application of the systemic insecticide, imidacloprid, had no effect on terrapin scale numbers. However, trunk-injected dicrotophos caused a reduction in scale and a decline in local Argentine ant nest density and canopy foraging effort. We also recorded a reduction in local Argentine ant ground foraging when large amounts of liquid bait were applied, and we found no evidence that combining dicrotophos with liquid ant bait performed better than each treatment alone. We suggest that a strategy of combined hemipteran control plus application of liquid ant bait can reduce local Argentine ant densities, when both components of this system are highly efficacious. PMID:21061981

  10. Biotic and abiotic controls of argentine ant invasion success at local and landscape scales

    USGS Publications Warehouse

    Menke, S.B.; Fisher, R.N.; Jetz, W.; Holway, D.A.

    2007-01-01

    Although the ecological success of introduced species hinges on biotic interactions and physical conditions, few experimental studies - especially on animals - have simultaneously investigated the relative importance of both types of factors. The lack of such research may stem from the common assumption that native and introduced species exhibit similar environmental tolerances. Here we combine experimental and spatial modeling approaches (1) to determine the relative importance of biotic and abiotic controls of Argentine ant (Linepithema humile) invasion success, (2) to examine how the importance of these factors changes with spatial scale in southern California (USA), and (3) to assess how Argentine ants differ from native ants in their environmental tolerances. A factorial field experiment that combined native ant removal with irrigation revealed that Argentine ants failed to invade any dry plots (even those lacking native ants) but readily invaded all moist plots. Native ants slowed the spread of Argentine ants into irrigated plots but did not prevent invasion. In areas without Argentine ants, native ant species showed variable responses to irrigation. At the landscape scale, Argentine ant occurrence was positively correlated with minimum winter temperature (but not precipitation), whereas native ant diversity increased with precipitation and was negatively correlated with minimum winter temperature. These results are of interest for several reasons. First, they demonstrate that fine-scale differences in the physical environment can eclipse biotic resistance from native competitors in determining community susceptibility to invasion. Second, our results illustrate surprising complexities with respect to how the abiotic factors limiting invasion can change with spatial scale, and third, how native and invasive species can differ in their responses to the physical environment. Idiosyncratic and scale-dependent processes complicate attempts to forecast where

  11. Analysis and modeling of concurrency, cycle time, and productivity in aerospace development projects

    NASA Astrophysics Data System (ADS)

    Hilscher, Richard Walter

    Engineering development projects are a key element of continued economic growth and profitability for companies that produce durable goods based on evolving technology. Today's world economy and the rapid pace of technology development necessitate a minimum development project cycle time to maximize the economic value of new products. Concurrent engineering and Integrated Product-Process Development (IPPD) evolved as an industry-wide strategy in the late 1980's and early 1990's to address the need for rapid product development and improved product quality. Rapid development of computer-based tools for communications and engineering has occurred in parallel with the emergence of concurrent engineering strategies. The combination of new computer tools and concurrent engineering practices has rendered many project management tools less effective or obsolete. New methods are needed for tracking progress and benchmarking projects employing concurrent engineering. Concurrent engineering and the resulting concurrency between specific activities within development projects has been associated with both positive and negative effects on project performance. This research applies empirical data analysis and computer simulation to evaluate these relationships using new metrics designed specifically for concurrent engineering analysis. By looking within the project at concurrency between specific activities, new insights have been gained into the nature and progress of concurrent engineering implementation. These relationships are useful tools in developing project plans with greater probability of success. A new metric for measuring concurrency is applied that uses the timing of information transactions between project activities and yields different conclusions than those related to time-based metrics. The research also applies a new methodology for comparison of project performance across product lines within aerospace. By using productivity rates and a new work content

  12. Environmental life cycle assessment of grain maize production: An analysis of factors causing variability.

    PubMed

    Boone, Lieselot; Van Linden, Veerle; De Meester, Steven; Vandecasteele, Bart; Muylle, Hilde; Roldán-Ruiz, Isabel; Nemecek, Thomas; Dewulf, Jo

    2016-05-15

    To meet the growing demand, high yielding, but environmentally sustainable agricultural plant production systems are desired. Today, life cycle assessment (LCA) is increasingly used to assess the environmental impact of these agricultural systems. However, the impact results are very diverse due to management decisions or local natural conditions. The impact of grain maize is often generalized and an average is taken. Therefore, we studied variation in production systems. Four types of drivers for variability are distinguished: policy, farm management, year-to-year weather variation and innovation. For each driver, scenarios are elaborated using ReCiPe and CEENE (Cumulative Exergy Extraction from the Natural Environment) to assess the environmental footprint. Policy limits fertilisation levels in a soil-specific way. The resource consumption is lower for non-sandy soils than for sandy soils, but entails however more eutrophication. Farm management seems to have less influence on the environmental impact when considering the CEENE only. But farm management choices such as fertiliser type have a large effect on emission-related problems (e.g. eutrophication and acidification). In contrast, year-to-year weather variation results in large differences in the environmental footprint. The difference in impact results between favourable and poor environmental conditions amounts to 19% and 17% in terms of resources and emissions respectively, and irrigation clearly is an unfavourable environmental process. The best environmental performance is obtained by innovation as plant breeding results in a steadily increasing yield over 25 years. Finally, a comparison is made between grain maize production in Flanders and a generically applied dataset, based on Swiss practices. These very different results endorse the importance of using local data to conduct LCA of plant production systems. The results of this study show decision makers and farmers how they can improve the

  13. [Oxygen therapy during Argentine-based national and international flights].

    PubMed

    Martínez Fraga, Alejandro; Sívori, Martín; Alonso, Mariana

    2008-01-01

    There are no data about supplemental oxygen in flight in our country. The objective of our study was to evaluate arranging in-flight-oxygen required by a simulated traveler, system of administration and costs, and to compare the results between Argentine-based (A) and international (I) airlines. The questionnaire used was similar to that of Stoller et al12. Data collection consisted of telephone calls placed by one of the authors to all commercial air carriers listed in our two Buenos Aires City airports during July 2007. A structured interview with questions was addressed on issues that an oxygen-using air traveler would need to arrange in-flight oxygen. Of the 25 airlines, 6 were discarded because of lack of information (24%, three A -60%- and one I -16%-). All A allowed in-flight-oxygen vs. 80% of I (p<0.05), 100% of A and 94% of I required a medical certificate (p=NS); 71% of A and 100% of I required previous notification (p<0.05); 50% of A and 87% of I provided patient interphases of oxygen administration (p=NS). Free of charge oxygen could be provided by 100% of A and 50% of I, with airline charge between 70 to 300 dollars. In conclusion, we observed different policies, rules, availability, and a pronounced lack of standardization of airline information. The cost of oxygen was very different between airlines and it was superior on I. It will be necessary to carry out actions to facilitate patient access to oxygentherapy and to standardize medical information among airlines in our country.

  14. Argentine experience in the field of illegal immigration.

    PubMed

    Villar, J M

    1984-01-01

    This article provides a brief history of Argentine policy toward migratory flows from neighboring countries and Europe, and concludes with statistics on the number of foreigners in Argentina in the 1970-80 period. Measures passed during the 1940s and 1950s were aimed at providing amnesty for foreigners who were residing in Argentina without immigrant status. However, the lack of an adequate administrative structure to regulate foreigners at the borders was a drawback for migration authorities and limited the possiblility of applying admission criteria effectively. By 1970, there were 583,000 foreigners from neighboring countries living in Argentina, which represented a 25% increase from 1960. 42% of these migrants were in the metropolitan region of the country, indicative of a shift away from employment in agriculture. Decree No. 87, passed in 1974, represented an extension of a migration policy aimed at granting ample facilities for permanent residence to aliens from contiguous countries and was designed to prevent abuse of clandestine workers by employers. As a result of this measure, 150,000 foreigners were able to settle legally in the country. A 1981 law, yet to be implemented, establishes a new legal framework aimed at fostering immigration and regulating the admission of foreigners. To attain the objective of settling workers in areas of the country considered of prime importance to economic development, the law provides for infrastructural investments and promotional measures in areas such as tax exemption and the granting of credit. The 1980 National Population Census indicated there were 677,000 foreigners from neighboring countries in Argentina. In that year, foreigners comprised 2.4% of the country's population and 3.1% of the inhabitants of the metropolitan region. These figures are indicative of a decline in the growth of immigration, most likely due to the decline in the purchasing power of workers' salaries in the late 1970s.

  15. Argentine experience in the field of illegal immigration.

    PubMed

    Villar, J M

    1984-01-01

    This article provides a brief history of Argentine policy toward migratory flows from neighboring countries and Europe, and concludes with statistics on the number of foreigners in Argentina in the 1970-80 period. Measures passed during the 1940s and 1950s were aimed at providing amnesty for foreigners who were residing in Argentina without immigrant status. However, the lack of an adequate administrative structure to regulate foreigners at the borders was a drawback for migration authorities and limited the possiblility of applying admission criteria effectively. By 1970, there were 583,000 foreigners from neighboring countries living in Argentina, which represented a 25% increase from 1960. 42% of these migrants were in the metropolitan region of the country, indicative of a shift away from employment in agriculture. Decree No. 87, passed in 1974, represented an extension of a migration policy aimed at granting ample facilities for permanent residence to aliens from contiguous countries and was designed to prevent abuse of clandestine workers by employers. As a result of this measure, 150,000 foreigners were able to settle legally in the country. A 1981 law, yet to be implemented, establishes a new legal framework aimed at fostering immigration and regulating the admission of foreigners. To attain the objective of settling workers in areas of the country considered of prime importance to economic development, the law provides for infrastructural investments and promotional measures in areas such as tax exemption and the granting of credit. The 1980 National Population Census indicated there were 677,000 foreigners from neighboring countries in Argentina. In that year, foreigners comprised 2.4% of the country's population and 3.1% of the inhabitants of the metropolitan region. These figures are indicative of a decline in the growth of immigration, most likely due to the decline in the purchasing power of workers' salaries in the late 1970s. PMID:12339919

  16. Life cycle environmental impacts of three products derived from wild-caught Antarctic krill (Euphausia superba).

    PubMed

    Parker, Robert W R; Tyedmers, Peter H

    2012-05-01

    Concern has been voiced in recent years regarding the environmental implications of the Antarctic krill fishery. Attention has focused primarily on ecological concerns, whereas other environmental aspects, including potentially globally problematic emissions and material and energy demands, have not been examined in detail. Here we apply life cycle assessment to measure the contributions of krill meal, oil, and omega-3 capsules to global warming, ozone depletion, acidification, eutrophication, energy use, and biotic resource use. Supply chains of one krill fishing and processing company, Aker BioMarine of Norway, were assessed. Impacts of krill products were found to be driven primarily by the combustion of fossil fuels onboard the fishing vessel and a transport/resupply vessel. Approximately 190 L of fuel are burned per tonne of raw krill landed, markedly higher than fuel inputs to reduction fisheries targeting other species. In contrast, the biotic resource use associated with extracting krill is relatively low compared to that of other reduction fisheries. Results of this study provide insight into the broader environmental implications of the krill fishery, comparisons between products derived from krill and other species targeted for reduction, opportunities for improving the fishery's performance, and a baseline against which to measure future performance. PMID:22480265

  17. Life cycle environmental impacts of three products derived from wild-caught Antarctic krill (Euphausia superba).

    PubMed

    Parker, Robert W R; Tyedmers, Peter H

    2012-05-01

    Concern has been voiced in recent years regarding the environmental implications of the Antarctic krill fishery. Attention has focused primarily on ecological concerns, whereas other environmental aspects, including potentially globally problematic emissions and material and energy demands, have not been examined in detail. Here we apply life cycle assessment to measure the contributions of krill meal, oil, and omega-3 capsules to global warming, ozone depletion, acidification, eutrophication, energy use, and biotic resource use. Supply chains of one krill fishing and processing company, Aker BioMarine of Norway, were assessed. Impacts of krill products were found to be driven primarily by the combustion of fossil fuels onboard the fishing vessel and a transport/resupply vessel. Approximately 190 L of fuel are burned per tonne of raw krill landed, markedly higher than fuel inputs to reduction fisheries targeting other species. In contrast, the biotic resource use associated with extracting krill is relatively low compared to that of other reduction fisheries. Results of this study provide insight into the broader environmental implications of the krill fishery, comparisons between products derived from krill and other species targeted for reduction, opportunities for improving the fishery's performance, and a baseline against which to measure future performance.

  18. Ocean carbon cycling in the Indian Ocean: 2. Estimates of net community production

    NASA Astrophysics Data System (ADS)

    Bates, Nicholas R.; Pequignet, A. Christine; Sabine, Christopher L.

    2006-09-01

    The spatiotemporal variability of ocean carbon cycling and air-sea CO2 exchange in the Indian Ocean was examined using inorganic carbon data collected as part of the World Ocean Circulation Experiment (WOCE) cruises in 1995. Several carbon mass balance approaches were used to estimate rates of net community production (NCP) in the Indian Ocean. Carbon transports into and out of the Indian Ocean were derived using mass transport estimates of Robbins and Toole (1997) and Schmitz (1996), and transoceanic hydrographic and TCO2 sections at 32°S and across the Indonesian Throughflow. The derived NCP rates of 749 ± 227 to 1572 ± 180 Tg C yr-1 (0.75-1.57 Pg C yr-1) estimated by carbon mass balance were similar to new production rates (1100-1800 Tg C yr-1) determined for the Indian Ocean by a variety of other methods (Louanchi and Najjar, 2000; Gnanadesikan et al., 2002). Changes in carbon inventories of the surface layer were also used to evaluate the spatiotemporal patterns of NCP. Significant NCP occurred in all regions during the Northeast Monsoon and Spring Intermonsoon periods. During the Southwest Monsoon and Fall Intermonsoon periods, the trophic status appears to shift from net autotrophy to net heterotrophy, particularly in the Arabian Sea, Bay of Bengal, and 10°N to 10°S zones.

  19. [Production cycles and risk agents in the agri-food sector].

    PubMed

    L'abbate, N; Lorusso, A; Lasalvia, M

    2010-01-01

    Italian Food Processing Section includes primary sector (agriculture, fishing and farming), secondary industry and service sector (trade, transport and marketing). The whole process is structured in a sequence of production structures, which constitute a die. The most important food processing dies are fruit and vegetable, cereals, wine, oil, bovine, swine and avian breeding, fishing, milk and cheese. Every die presents very different production cycles, jobs and working professionals. Considering the heterogeneity of food processing dies, all occupational risk factors, such as chemical, biological, physical, ergonomic, psychosocial and injuries risks, are very frequent in such working activities. In a pilot study carried out in the province of Foggia (Apulia, Southern Italy) we showed that the major perceived risk factors where dust and physical overload in the cereal-pasta processing die, and noise and awkward postures in olive-oil die. However, perceived risk factors are biased by low risk perception due to poor information about health occupational hazards, this representing an important health safety problem. For this reason, the activity of preventive authorities at various levels is highly recommended. PMID:21442781

  20. [Production cycles and risk agents in the agri-food sector].

    PubMed

    L'abbate, N; Lorusso, A; Lasalvia, M

    2010-01-01

    Italian Food Processing Section includes primary sector (agriculture, fishing and farming), secondary industry and service sector (trade, transport and marketing). The whole process is structured in a sequence of production structures, which constitute a die. The most important food processing dies are fruit and vegetable, cereals, wine, oil, bovine, swine and avian breeding, fishing, milk and cheese. Every die presents very different production cycles, jobs and working professionals. Considering the heterogeneity of food processing dies, all occupational risk factors, such as chemical, biological, physical, ergonomic, psychosocial and injuries risks, are very frequent in such working activities. In a pilot study carried out in the province of Foggia (Apulia, Southern Italy) we showed that the major perceived risk factors where dust and physical overload in the cereal-pasta processing die, and noise and awkward postures in olive-oil die. However, perceived risk factors are biased by low risk perception due to poor information about health occupational hazards, this representing an important health safety problem. For this reason, the activity of preventive authorities at various levels is highly recommended.

  1. Life cycle of medical product rules issued by the US Food and Drug Administration.

    PubMed

    Hwang, Thomas J; Avorn, Jerry; Kesselheim, Aaron S

    2014-08-01

    The US Food and Drug Administration (FDA) uses rulemaking as one of its primary tools to protect the public health and implement laws enacted by Congress and the president. Because of the many effects that these rules have on social welfare and the economy, the FDA and other executive agencies receive input from the executive branch, the public, and in some cases, the courts, during the process of rulemaking. In this article, we examine the life cycle of FDA regulations concerning medical products and review notable features of the rulemaking process. The current system grants substantial opportunities for diverse stakeholders to participate in and influence how rules are written and implemented. However, the duration, complexity, and adversarial qualities of the rulemaking process can hinder the FDA's ability to achieve its policy and public health goals. There is considerable variation in the level of transparency at different stages in the process, ranging from freely accessible public comments to undisclosed internal agency deliberations. In addition, significant medical product rules are associated with lengthy times to finalization, in some cases for unclear reasons. We conclude by identifying potential areas for reform on the basis of transparency and efficiency.

  2. Effect of copper contaminated food on the life cycle and secondary production of Daphnia laevis.

    PubMed

    Rocha, Giseli S; Tonietto, Alessandra E; Lombardi, Ana T; Melão, Maria da G G

    2016-11-01

    In aquatic environments, copper (Cu) plays important physiological roles in planktonic food chain, such as electron transfer in photosynthesis and constituting proteins that transport oxygen in some arthropods, while at higher concentrations it is toxic on these organisms and higher trophic levels. The combined effects of natural (e.g. volcanic activity) and anthropogenic sources (e.g. mining waste) contribute to the increase in copper pollution in different ecosystems and regions around the world. In the present study, we evaluated the bioaccumulation and effect of Cu on Raphidocelis subcapitata (freshwater algae), and the influence of Cu-contaminated food (algae) on Daphnia laevis (tropical cladoceran). The amount of copper accumulated in microalgae and cladoceran was quantified, and life-history parameters of D. laevis such as growth, reproduction and longevity were measured. The cell density of Cu exposed R. subcapitata declined, and cladoceran fed with contaminated food had lower longevity, production of eggs and neonates, and reduced secondary production. A concentration dependent increase in Cu accumulation was observed in the microalgae, while the opposite occurred in the animal, indicating a cellular metal regulatory mechanism in the latter. However, this regulation seems not to be sufficient to avoid metal induced damages in the cladoceran such as decreased longevity and reproduction. We conclude that diet is an important metal exposure route to this cladoceran, and the assessment of chronic contamination during the complete life cycle of cladoceran provides results that are similar to those observed in natural environments, especially when native organisms are investigated. PMID:27472028

  3. Satellite-based Biome Productivity Responses to Large Scale Drought and Wet Cycles in Australia

    NASA Astrophysics Data System (ADS)

    Huete, A. R.; Ma, X.; Ponce-Campos, G. E.; Moran, S. M.; Davies, K.; Restrepo-Coupe, N.; Broich, M.; Eamus, D.

    2012-12-01

    Australia's climate is extremely variable with inter annual rainfall at any location varying up to eight-fold. Understanding water and productivity relationships represent key issues in climate change models that aim to predict how carbon and water relationships will shift with projected changes in the frequency, timing, amount and intensity of rainfall. After a decadal long drought cycle, Australia has experienced one of the wettest periods of recorded rainfall. In this study we assessed cross-biome responses to extreme drought and wet periods across continental Australia through investigations of rainfall use efficiencies (RUE), defined as above-ground net primary production (ANPP) divided by annual rainfall. 12 years of annually integrated MODIS satellite enhanced vegetation index (iEVI) were used as proxies of ANPP and combined with rainfall data to assess large area spatial and temporal patterns in rainfall use efficiency (RUE). Positive curvilinear relationships were found between iEVI and annual rainfall with decreasing sensitivity of iEVI to additional rainfall at the more humid and energy-limited tropical savannas and forests. The driest years resulted in all biomes converging to a common and maximum RUE, or RUEmax with ANPP and precipitation relationships that became strongly linear. Standardized anomaly values showed significantly enhanced ANPP values during the 2010 and 2011 wet years, however, these values were less than encountered prior to the decade long drought, suggesting a significant loss in resilience in many Australian biomes.

  4. Effect of copper contaminated food on the life cycle and secondary production of Daphnia laevis.

    PubMed

    Rocha, Giseli S; Tonietto, Alessandra E; Lombardi, Ana T; Melão, Maria da G G

    2016-11-01

    In aquatic environments, copper (Cu) plays important physiological roles in planktonic food chain, such as electron transfer in photosynthesis and constituting proteins that transport oxygen in some arthropods, while at higher concentrations it is toxic on these organisms and higher trophic levels. The combined effects of natural (e.g. volcanic activity) and anthropogenic sources (e.g. mining waste) contribute to the increase in copper pollution in different ecosystems and regions around the world. In the present study, we evaluated the bioaccumulation and effect of Cu on Raphidocelis subcapitata (freshwater algae), and the influence of Cu-contaminated food (algae) on Daphnia laevis (tropical cladoceran). The amount of copper accumulated in microalgae and cladoceran was quantified, and life-history parameters of D. laevis such as growth, reproduction and longevity were measured. The cell density of Cu exposed R. subcapitata declined, and cladoceran fed with contaminated food had lower longevity, production of eggs and neonates, and reduced secondary production. A concentration dependent increase in Cu accumulation was observed in the microalgae, while the opposite occurred in the animal, indicating a cellular metal regulatory mechanism in the latter. However, this regulation seems not to be sufficient to avoid metal induced damages in the cladoceran such as decreased longevity and reproduction. We conclude that diet is an important metal exposure route to this cladoceran, and the assessment of chronic contamination during the complete life cycle of cladoceran provides results that are similar to those observed in natural environments, especially when native organisms are investigated.

  5. Combining life cycle assessment and qualitative risk assessment: the case study of alumina nanofluid production.

    PubMed

    Barberio, Grazia; Scalbi, Simona; Buttol, Patrizia; Masoni, Paolo; Righi, Serena

    2014-10-15

    In this paper the authors propose a framework for combining life cycle assessment (LCA) and Risk Assessment (RA) to support the sustainability assessment of emerging technologies. This proposal includes four steps of analysis: technological system definition; data collection; risk evaluation and impacts quantification; results interpretation. This scheme has been applied to a case study of nanofluid alumina production in two different pilot lines, "single-stage" and "two-stage". The study has been developed in the NanoHex project (enhanced nano-fluid heat exchange). Goals of the study were analyzing the hotspots and highlighting possible trade-off between the results of LCA, which identifies the processes having the best environmental performance, and the results of RA, which identifies the scenarios having the highest risk for workers. Indeed, due to lack of data about exposure limits, exposure-dose relationships and toxicity of alumina nanopowders (NPs) and nanofluids (NF), the workplace exposure has been evaluated by means of qualitative risk assessment, using Stoffenmanager Nano. Though having different aims, LCA and RA have a complementary role in the description of impacts of products/substances/technologies. Their combined use can overcome limits of each of them and allows a wider vision of the problems to better support the decision making process.

  6. Structure, composition and metagenomic profile of soil microbiomes associated to agricultural land use and tillage systems in Argentine Pampas.

    PubMed

    Carbonetto, Belén; Rascovan, Nicolás; Álvarez, Roberto; Mentaberry, Alejandro; Vázquez, Martin P

    2014-01-01

    Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no-tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment) presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional tillage systems may

  7. Structure, composition and metagenomic profile of soil microbiomes associated to agricultural land use and tillage systems in Argentine Pampas.

    PubMed

    Carbonetto, Belén; Rascovan, Nicolás; Álvarez, Roberto; Mentaberry, Alejandro; Vázquez, Martin P

    2014-01-01

    Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no-tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment) presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional tillage systems may

  8. Structure, Composition and Metagenomic Profile of Soil Microbiomes Associated to Agricultural Land Use and Tillage Systems in Argentine Pampas

    PubMed Central

    Carbonetto, Belén; Rascovan, Nicolás; Álvarez, Roberto; Mentaberry, Alejandro; Vázquez, Martin P.

    2014-01-01

    Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no- tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment) presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional tillage systems

  9. The Utility of Seasonal Climate Forecasts: Understanding Argentine Farmers' Attribute Priorities and Trade-Offs

    NASA Astrophysics Data System (ADS)

    Seipt, E. C.; Easterling, W. E.

    2007-05-01

    A distinct El Niño - Southern Oscillation (ENSO) signal and its impacts have been confirmed in the Argentine Pampas, and precipitation variability is currently recognized as the region's most marked ENSO-driven influence. In the Pampas, precipitation is also a major limiting factor for agricultural production given spatial differences in soil water storage capacities and the region's relatively minimal use of irrigation. Seasonal climate forecasts that provide advanced knowledge of expected ENSO-driven precipitation anomalies may benefit farm management decision-making by helping to either mitigate potentially negative consequences or to take advantage of potentially positive influences. To be useful and applicable, however, these forecasts must suit the decisions that they are meant to inform. In this research, a case study is presented that investigates how farmers in the Pampas prioritize and trade off specific attributes of a seasonal climate forecast (i.e., mode of distribution, spatial resolution, lead time, and forecast performance) when judging its utility. A conjoint analysis evaluation decomposes holistic evaluations of forecasts into the part-worth utilities associated with their different attributes. Part-worth utilities combine to reveal the structure of farmers' forecast utility preferences - a model of the decision-making process. Utility preference structures are analyzed to compute the importance value of each attribute and to determine the trade-offs that farmers find acceptable between different attributes. Analysis indicates that, on average, spatial resolution is the most influential attribute in determining climate forecast utility. Attribute trade-off values suggest that advances in spatial resolution, forecast performance, and/or product dissemination via the Internet offer the greatest potential for increasing the utility of future seasonal climate forecasts for farmers in the Pampas.

  10. Copper chloride electrolyzer for the production of hydrogen via the copper-chlorine thermochemical cycle

    NASA Astrophysics Data System (ADS)

    Roy, Rahul Dev

    Hydrogen is considered a key element in solving the upcoming energy crisis, it is not the primary fuel source but an "energy carrier" similar to electricity and has to be produced using some other hydrogen rich source. Thermochemical water decomposition is a promising alternative to steam-methane reforming and electrolytic water splitting for a sustainable method of large-scale hydrogen production. The Copper-Chlorine thermochemical cycle is one of prime contenders among all the other thermochemical cycles being studied because of its low energy requirements compared to others and mild operating conditions, therefore making it available to be readily integrated to the available nuclear reactors or solar energy installations. This present work focuses on the study and development of a proton exchange membrane (PEM) electrolyzer cell for the Copper-Chlorine thermo chemical cycle to obtain a better understanding through experiments and models of this process. Different operating and design parameters such as temperature, flow rate, current density, membranes and gas diffusion layers were considered to reduce the voltage and hence increase the efficiency of the electrolyzer. The effects of catalyst and mass transfer were studied on the thin film electrode using a rotating disk electrode (RDE) setup. A mathematical model was also developed to monitor the performance of the electrolyzer by predicting the change in concentration of copper chloride in the system with respect to time. It is observed that flow rate and temperature plays a major role in decreasing the voltage drop. There was no effect of catalyst in the anode when compared to a bare anode at lower flow rates; but at higher flow rates there was significant decrease in voltage drop when a carbon cloth was placed at the anode end. High surface area carbon black has comparable activity towards CuCl oxidation with conventional catalyst like Platinum or Ruthenium oxide. It is also seen that mass transfers possess a

  11. Production and measurement of minor actinides in the commercial fuel cycle

    SciTech Connect

    Stanbro, W.D.

    1997-03-01

    The minor actinide elements, particularly neptunium and americium, are produced as a normal byproduct of the operation of thermal power reactors. Because of the existence of long-lived isotopes of these elements, they constitute the major sources of the residual radiation in spent fuel or in wastes resulting from reprocessing. This has led to examinations by some countries of the possibility of separating the minor actinides from waste products. The papers found in this report address the production of minor actinides in common thermal power reactors as well as approaches to measure these materials in various media. The first paper in this volume, {open_quotes}Production of Minor Actinides in the Commercial Fuel Cycle,{close_quotes} uses calculations with the ORIGEN2 reactor and decay code to estimate the amounts of minor actinides in spent fuel and separated plutonium as a function of reactor irradiation and the time after discharge. The second paper, {open_quotes}Destructive Assay of Minor Actinides,{close_quotes} describes a number of promising approaches for the chemical analysis of minor actinides in the various forms in which they are found at reprocessing plants. The next paper, {open_quotes}Hybrid KED/XRF Measurement of Minor Actinides in Reprocessing Plants,{close_quotes} uses the results of a simulation model to examine the possible applications of the hybrid KED/XRF instrument to the determination of minor actinides in some of the solutions found in reprocessing plants. In {open_quotes}Calorimetric Assay of Minor Actinides,{close_quotes} the authors show some possible extensions of this powerful technique beyond the normal plutonium assays to include the minor actinides. Finally, the last paper in this volume, {open_quotes}Environment Measurements of Transuranic Nuclides,{close_quotes} discusses what is known about the levels of the minor actinides in the environment and ways to analyze for these materials in environmental matrices.

  12. Review of the rice production cycle: by-products and the main applications focusing on rice husk combustion and ash recycling.

    PubMed

    Moraes, Carlos A M; Fernandes, Iara J; Calheiro, Daiane; Kieling, Amanda G; Brehm, Feliciane A; Rigon, Magali R; Berwanger Filho, Jorge A; Schneider, Ivo A H; Osorio, Eduardo

    2014-11-01

    One of the consequences of industrial food production activities is the generation of high volumes of waste, whose disposal can be problematic, since it occupies large spaces, and when poorly managed can pose environmental and health risks for the population. The rice industry is an important activity and generates large quantities of waste. The main solid wastes generated in the rice production cycle include straw, husk, ash, bran and broken rice. As such, the aim of this article is to present a review of this cycle, the waste generated and the identification of opportunities to use them. Owing to impacts that can be minimised with the application of rice husk ash as a by-product, this work is focused on the recycling of the main wastes. In order to achieve that, we performed theoretical research about the rice production cycle and its wastes. The findings point to the existence of an environmentally suitable use for all wastes from the rice production cycle. As rice, bran and broken rice have their main use in the food industry, the other wastes are highly studied in order to find solutions instead of landfilling. Straw can be used for burning or animal feeding. The husk can be used for poultry farming, composting or burning. In the case of burning, it has been used as biomass to power reactors to generate thermal or electrical energy. This process generates rice husk ash, which shows potential to be used as a by-product in many different applications, but not yet consolidated.

  13. Impact of sea ice on the marine iron cycle and phytoplankton productivity

    NASA Astrophysics Data System (ADS)

    Wang, S.; Bailey, D.; Lindsay, K.; Moore, J. K.; Holland, M.

    2014-09-01

    Iron is a key nutrient for phytoplankton growth in the surface ocean. At high latitudes, the iron cycle is closely related to the dynamics of sea ice. In recent decades, Arctic sea ice cover has been declining rapidly and Antarctic sea ice has exhibited large regional trends. A significant reduction of sea ice in both hemispheres is projected in future climate scenarios. In order to adequately study the effect of sea ice on the polar iron cycle, sea ice bearing iron was incorporated in the Community Earth System Model (CESM). Sea ice acts as a reservoir for iron during winter and releases the trace metal to the surface ocean in spring and summer. Simulated iron concentrations in sea ice generally agree with observations in regions where iron concentrations are relatively low. The maximum iron concentrations simulated in Arctic and Antarctic sea ice are much lower than observed, which is likely due to underestimation of iron inputs to sea ice or missing mechanisms. The largest iron source to sea ice is suspended sediments, contributing fluxes of iron of 2.2 × 108 mol Fe month-1 in the Arctic and 4.1 × 106 mol Fe month-1 in the Southern Ocean during summer. As a result of the iron flux from ice, iron concentrations increase significantly in the Arctic. Iron released from melting ice increases phytoplankton production in spring and summer and shifts phytoplankton community composition in the Southern Ocean. Results for the period of 1998 to 2007 indicate that a reduction of sea ice in the Southern Ocean will have a negative influence on phytoplankton production. Iron transport by sea ice appears to be an important process bringing iron to the central Arctic. The impact of ice to ocean iron fluxes on marine ecosystems is negligible in the current Arctic Ocean, as iron is not typically the growth-limiting nutrient. However, it may become a more important factor in the future, particularly in the central Arctic, as iron concentrations will decrease with declining sea

  14. Argentine Hydrellia Robineau-Desvoidy (Diptera, Ephydridae): new species and key to identification.

    PubMed

    Rodrigues Júnior, Francisco De Assis; Mathis, Wayne Nielsen; Hauser, Martin

    2015-05-13

    Hydrellia egeriae sp. nov., a new species of Hydrellia from Campana (34 14' 04 S, 58 52' 32 W) and Hurlingham (3435'14 S, 5838'27 W), Buenos Aires province, Argentina is described. A key to the Argentine Hydrellia species is presented.

  15. Library Networks in Less-Developed Countries: Two Argentine Cases and Some Observations.

    ERIC Educational Resources Information Center

    Tang, Donna Taxco

    As an American Library Association/USIA International Library Fellow in Argentina from March to September 1989, the author worked with the Argentine National Protective Commission for People's Libraries. Included in her assignment was a charge "to assist in the development of a popular libraries network in Patagonia," the southernmost region of…

  16. Schooling and Governance: Pedagogical Knowledge and Bureaucratic Expertise in the Genesis of the Argentine Educational System

    ERIC Educational Resources Information Center

    Southwell, Myriam

    2013-01-01

    The consolidation of the Argentine Federal Government by the 1870s aimed to modernise local society, establish state institutions and reach political stabilisation. Building a modern schooling system articulated both utopia and bureaucracy by establishing the use of knowledge as an instrument of social intervention, vindicating and legitimising…

  17. Self-Assessment of Governance Teams in an Argentine Private University: Adapting to Difficult Times

    ERIC Educational Resources Information Center

    Durand, Julio; Pujadas, Carlos

    2004-01-01

    Argentine Universities like similar institutions all around the world are facing a complex and challenging environment that demands a more sophisticated leadership and the development of complex managerial skills. In this paper we propose that enhancing the quality of collective decision making, and building more complex teams as a way to preserve…

  18. English as an Instrumental Language: Language Displacement in the Anglo-Argentine Community.

    ERIC Educational Resources Information Center

    Cortes-Conde, Florencia

    1994-01-01

    Surveyed 99 Anglo-Argentine students aged 10 through 18 at five Spanish-English bilingual schools in Buenos Aires about their language attitudes and usage. It found that, despite the prestige of the English language, Spanish had become the dominant language for most. Age and place of residency in Buenos Aires also had a significant effect on…

  19. Indirect water management through Life Cycle Assessment: Fostering sustainable production in developing countries

    NASA Astrophysics Data System (ADS)

    Pfister, S.; Bayer, P.; Koehler, A.; Hellweg, S.

    2009-04-01

    Life Cycle Assessment (LCA) represents a methodological framework for analyzing the total environmental impact of any product or service of our daily life. After tracking all associated emissions and the consumption of resources, this impact is expressed with respect to a few common impact categories. These are supposed to reflect major societal and environmental priorities. However, despite their central role in environmental processes, to date hydrological as well as hydrogeological aspects are only rarely considered in LCA. Compared with standard impact categories within LCA, water is special. In contrast to other abiotic resources such as crude oil, it can be replenished. Total freshwater resources are immense, but not evenly distributed and often scarce in regions of high demand. Consequently, threads to natural water bodies have immense spatial dependency. Setting up functional relationships in order to derive a generally valid and practicable evaluation is tedious due to the complex, insufficiently understood, and uncertain natural processes involved. LCA that includes the environmental effects of water consumption means global indirect water resource management. It supports goal-directed consumer behaviour that aims to reduce pressure on natural water systems. By developing a hydrologically-based assessment of potential impacts from human interaction with natural water bodies, "greener" products can be prioritised. More sustainable and environmentally friendly water management is the result. The proposed contribution presents an operational assessment method of global surface water consumption for impacts on human health and ecosystem quality within a LCA framework. A major focus is the issue of how such global assessment helps to quantify potential impacts from water-intensive production in developing countries, where the means for proper water management are often limited. We depict a compensation scheme for impacts related to water consumption that

  20. A study on the magnesium-iodine thermochemical cycle for the production of hydrogen

    NASA Astrophysics Data System (ADS)

    Hakuta, T.; Haraya, K.; Sako, T.; Ito, N.; Yoshitome, H.; Todo, N.; Kato, J.

    The rates of redox reaction of magnesium oxide and iodine in water and of the thermal decomposition of magnesium iodate are investigated in order to design a hydrogen production process using the magnesium-iodine cycle for the thermochemical decomposition of water. The optimal conditions of the redox reaction are determined; they are an initial molar ratio of MgO:I2:H2O =1:5:8, a temperature of 150 C, and a reaction time of 15 to 20 min. The thermal decomposition of magnesium iodate is found to be a two-step reaction which starts at 588 and 615 C, respectively. It is noted that the enthalpy change of magnesium iodate to intermediate paraperiodate - Mg5(IO6)2 - is 65.4 kcal/mol and that of paraperiodate to magnesium oxide is 99.0 kcal/mol. The vapor pressures of liquid iodine, magnesium iodide, and MgI2-I2 aqueous solutions are measured, and the data are fitted to the Antoine equation by the least squares method.

  1. Cost versus life cycle assessment-based environmental impact optimization of drinking water production plants.

    PubMed

    Capitanescu, F; Rege, S; Marvuglia, A; Benetto, E; Ahmadi, A; Gutiérrez, T Navarrete; Tiruta-Barna, L

    2016-07-15

    Empowering decision makers with cost-effective solutions for reducing industrial processes environmental burden, at both design and operation stages, is nowadays a major worldwide concern. The paper addresses this issue for the sector of drinking water production plants (DWPPs), seeking for optimal solutions trading-off operation cost and life cycle assessment (LCA)-based environmental impact while satisfying outlet water quality criteria. This leads to a challenging bi-objective constrained optimization problem, which relies on a computationally expensive intricate process-modelling simulator of the DWPP and has to be solved with limited computational budget. Since mathematical programming methods are unusable in this case, the paper examines the performances in tackling these challenges of six off-the-shelf state-of-the-art global meta-heuristic optimization algorithms, suitable for such simulation-based optimization, namely Strength Pareto Evolutionary Algorithm (SPEA2), Non-dominated Sorting Genetic Algorithm (NSGA-II), Indicator-based Evolutionary Algorithm (IBEA), Multi-Objective Evolutionary Algorithm based on Decomposition (MOEA/D), Differential Evolution (DE), and Particle Swarm Optimization (PSO). The results of optimization reveal that good reduction in both operating cost and environmental impact of the DWPP can be obtained. Furthermore, NSGA-II outperforms the other competing algorithms while MOEA/D and DE perform unexpectedly poorly.

  2. Cost versus life cycle assessment-based environmental impact optimization of drinking water production plants.

    PubMed

    Capitanescu, F; Rege, S; Marvuglia, A; Benetto, E; Ahmadi, A; Gutiérrez, T Navarrete; Tiruta-Barna, L

    2016-07-15

    Empowering decision makers with cost-effective solutions for reducing industrial processes environmental burden, at both design and operation stages, is nowadays a major worldwide concern. The paper addresses this issue for the sector of drinking water production plants (DWPPs), seeking for optimal solutions trading-off operation cost and life cycle assessment (LCA)-based environmental impact while satisfying outlet water quality criteria. This leads to a challenging bi-objective constrained optimization problem, which relies on a computationally expensive intricate process-modelling simulator of the DWPP and has to be solved with limited computational budget. Since mathematical programming methods are unusable in this case, the paper examines the performances in tackling these challenges of six off-the-shelf state-of-the-art global meta-heuristic optimization algorithms, suitable for such simulation-based optimization, namely Strength Pareto Evolutionary Algorithm (SPEA2), Non-dominated Sorting Genetic Algorithm (NSGA-II), Indicator-based Evolutionary Algorithm (IBEA), Multi-Objective Evolutionary Algorithm based on Decomposition (MOEA/D), Differential Evolution (DE), and Particle Swarm Optimization (PSO). The results of optimization reveal that good reduction in both operating cost and environmental impact of the DWPP can be obtained. Furthermore, NSGA-II outperforms the other competing algorithms while MOEA/D and DE perform unexpectedly poorly. PMID:27107954

  3. Evaluation of Life-Cycle Assessment Studies of Chinese Cement Production: Challenges and Opportunities

    SciTech Connect

    Lu, Hongyou; Masanet, Eric; Price, Lynn

    2009-05-29

    The use of life-cycle assessment (LCA) to understand the embodied energy, environmental impacts, and potential energy-savings of manufactured products has become more widespread among researchers in recent years. This paper reviews recent LCA studies in the cement industry in China and in other countries and provides an assessment of the methodology used by the researchers compared to ISO LCA standards (ISO 14040:2006, ISO 14044:2006, and ISO/TR 14048:2002). We evaluate whether the authors provide information on the intended application, targeted audience, functional unit, system boundary, data sources, data quality assessment, data disaggregation and other elements, and draw conclusions regarding the level of adherence to ISO standards for the papers reviewed. We found that China researchers have gained much experience during last decade, but still have room for improvement in establishing boundaries, assessing data quality, identifying data sources, and explaining limitations. The paper concludes with a discussion of directions for future LCA research in China.

  4. Life cycle assessment of potential biojet fuel production in the United States.

    PubMed

    Agusdinata, Datu B; Zhao, Fu; Ileleji, Klein; DeLaurentis, Dan

    2011-11-01

    The objective of this paper is to reveal to what degree biobased jet fuels (biojet) can reduce greenhouse gas (GHG) emissions from the U.S. aviation sector. A model of the supply and demand chain of biojet involving farmers, biorefineries, airlines, and policymakers is developed by considering factors that drive the decisions of actors (i.e., decision-makers and stakeholders) in the life cycle stages. Two kinds of feedstock are considered: oil-producing feedstock (i.e., camelina and algae) and lignocellulosic biomass (i.e., corn stover, switchgrass, and short rotation woody crops). By factoring in farmer/feedstock producer and biorefinery profitability requirements and risk attitudes, land availability and suitability, as well as a time delay and technological learning factor, a more realistic estimate of the level of biojet supply and emissions reduction can be developed under different oil price assumptions. Factors that drive biojet GHG emissions and unit production costs from each feedstock are identified and quantified. Overall, this study finds that at likely adoption rates biojet alone would not be sufficient to achieve the aviation emissions reduction target. In 2050, under high oil price scenario assumption, GHG emissions can be reduced to a level ranging from 55 to 92%, with a median value of 74%, compared to the 2005 baseline level. PMID:21958200

  5. Organization of Human Papillomavirus Productive Cycle during Neoplastic Progression Provides a Basis for Selection of Diagnostic Markers

    PubMed Central

    Middleton, Kate; Peh, Woei; Southern, Shirley; Griffin, Heather; Sotlar, Karl; Nakahara, Tomomi; El-Sherif, Amira; Morris, Lesley; Seth, Rashmi; Hibma, Merilyn; Jenkins, David; Lambert, Paul; Coleman, Nicholas; Doorbar, John

    2003-01-01

    The productive cycle of human papillomaviruses (HPVs) can be divided into discrete phases. Cell proliferation and episomal maintenance in the lower epithelial layers are followed by genome amplification and the expression of capsid proteins. These events, which occur in all productive infections, can be distinguished by using antibodies to viral gene products or to surrogate markers of their expression. Here we have compared precancerous lesions caused by HPV type 16 (HPV16) with lesions caused by HPV types that are not generally associated with human cancer. These include HPV2 and HPV11, which are related to HPV16 (supergroup A), as well as HPV1 and HPV65, which are evolutionarily divergent (supergroups E and B). HPV16-induced low-grade squamous intraepithelial lesions (CIN1) are productive infections which resemble those caused by other HPV types. During progression to cancer, however, the activation of late events is delayed, and the thickness of the proliferative compartment is progressively increased. In many HPV16-induced high-grade squamous intraepithelial lesions (CIN3), late events are restricted to small areas close to the epithelial surface. Such heterogeneity in the organization of the productive cycle was seen only in lesions caused by HPV16 and was not apparent when lesions caused by other HPV types were compared. By contrast, the order in which events in the productive cycle were initiated was invariant and did not depend on the infecting HPV type or the severity of disease. The distribution of viral gene products in the infected cervix depends on the extent to which the virus can complete its productive cycle, which in turn reflects the severity of cervical neoplasia. It appears from our work that the presence of such proteins in cells at the epithelial surface allows the severity of the underlying disease to be predicted and that markers of viral gene expression may improve cervical screening. PMID:12970404

  6. Abiotic factors control invasion by Argentine ants at the community scale.

    PubMed

    Menke, Sean B; Holway, David A

    2006-03-01

    1. A prominent and unresolved question in ecology concerns why communities differ in their susceptibility to invasion. While studies often emphasize biotic resistance, it is less widely appreciated how the physical environment affects community vulnerability to invasion. 2. In this study we performed field experiments to test how abiotic variation directly and indirectly influences the extent to which Linepithema humile Mayr (Argentine ants) invade seasonally dry environments in southern California. 3. In controlled and replicated experiments involving drip irrigation, we demonstrate (i) that elevated levels of soil moisture increased both the abundance of Argentine ants and their ability to invade native ant communities and (ii) that cessation of irrigation caused declines in the abundance of Argentine ants and led to their withdrawal from previously occupied areas. 4. Because drip irrigation stimulated plant growth, in an additional experiment we manipulated both soil moisture and plant cover to assess the direct vs. indirect effects of added water on the abundance of L. humile. 5. Local abundance of Argentine ants increased in irrigated plots but was 38% higher in irrigated plots with plants compared to irrigated plots where plant growth was suppressed. The results of this experiment thus argue for a direct role of soil moisture in influencing Argentine ant abundance but suggest that that the indirect effects of added water may also be important. 6. Our study illustrates more generally that fine-scale variation in the physical environment can control whether communities become invaded by non-native species and suggests that an understanding of community susceptibility to invasion will be improved by a better appreciation of interactions between the biotic and abiotic environment.

  7. Giant mudwaves in the Northern Argentine Basin: born and buried by bottom currents

    NASA Astrophysics Data System (ADS)

    Borisov, Dmitrii; Murdmaa, Ivar; Ivanova, Elena; Levchenko, Oleg

    2014-05-01

    shape of the mudwaves suggests either a low average current velocity (< 9 cm/s) during the last 130 ka or frequent changes in the flow direction. Burial of the northern part of mudwaves field was related to a considerable decrease in bottom currents velocity that resulted in a short-term cessation of contourites accumulation replaced by hemipelagic sedimentation. Recovered hemipelagites are deposited during the last deglaciation, as inferred from the planktic foraminiferal data. Flow velocities decreased either owing to lower AABW production or to current system shifting. Buried sediment waves in the structure of the Santa Catarina drift indicate that waves formation and burial are cyclic processes characterizing the evolution of the studied contourite depositional system in the northern Argentine Basin affected by the global climate change and glacioeustatic sea level oscillation. The study was partially supported by RFBR, research project No. 14-05-31357. 1. BleiI U. et al. Report and Preliminary Results of METEOR Cruise 23/2, Rio de Janeiro - Recife, 27.02.1993 - 19.03.1993. Berichte, Fachbereich Geowissenschaften, Universität Bremen, 1993. N. 43. 133 pp. 2. Marine Geoscience Data System GeoMapApp (geomapapp.org)

  8. Analyzing Nuclear Fuel Cycles from Isotopic Ratios of Waste Products Applicable to Measurement by Accelerator Mass Spectrometry

    SciTech Connect

    Biegalski, S R; Whitney, S M; Buchholz, B

    2005-08-24

    An extensive study was conducted to determine isotopic ratios of nuclides in spent fuel that may be utilized to reveal historical characteristics of a nuclear reactor cycle. This forensic information is important to determine the origin of unknown nuclear waste. The distribution of isotopes in waste products provides information about a nuclear fuel cycle, even when the isotopes of uranium and plutonium are removed through chemical processing. Several different reactor cycles of the PWR, BWR, CANDU, and LMFBR were simulated for this work with the ORIGEN-ARP and ORIGEN 2.2 codes. The spent fuel nuclide concentrations of these reactors were analyzed to find the most informative isotopic ratios indicative of irradiation cycle length and reactor design. Special focus was given to long-lived and stable fission products that would be present many years after their creation. For such nuclides, mass spectrometry analysis methods often have better detection limits than classic gamma-ray spectroscopy. The isotopic ratios {sup 151}Sm/{sup 146}Sm, {sup 149}Sm/{sup 146}Sm, and {sup 244}Cm/{sup 246}Cm were found to be good indicators of fuel cycle length and are well suited for analysis by accelerator mass spectroscopy.

  9. Months of asynchrony in offspring production but synchronous adult emergence: the role of diapause in an ectoparasite's life cycle.

    PubMed

    Härkönen, Laura; Kaitala, Arja

    2013-12-01

    Off-host stages of temperate zone ectoparasites must overcome two challenges: coping with unfavorable seasons and synchronizing their life cycles with host availability. In general, little is known about the seasonal cycles of insect ectoparasites of warm-blooded animals. The current study investigates the unusual phenology of a viviparous hippoboscid fly, the deer ked (Lipoptena cervi L.), that parasitizes boreal cervids. Despite months of asynchrony in offspring production, the adults emerge synchronously in mid-August across the northern boreal zone. We examined the role of diapause variation in the synchronization of life cycles by testing adult emergence success and time in relation to offspring birth month (October to April) and with respect to chilling time and photoperiod. Unexpectedly, we found that photoperiod had no role in regulating the life cycle, but diapause was maintained as long as pupae were exposed to cold. Pupae born before February needed a slightly longer exposure to high temperatures to terminate diapause if the cold period was short. Despite the apparent importance of a long period of chilling for life cycle synchrony, it was not required to terminate diapause. This finding of cold mainly preventing, rather than promoting, diapause termination is not novel among temperate insects, but it is rare. Slow diapause termination as a response to exceptionally long exposure to high, not low, temperatures seems to be a cornerstone for synchronizing the life cycle in the deer ked. PMID:24216221

  10. Months of asynchrony in offspring production but synchronous adult emergence: the role of diapause in an ectoparasite's life cycle.

    PubMed

    Härkönen, Laura; Kaitala, Arja

    2013-12-01

    Off-host stages of temperate zone ectoparasites must overcome two challenges: coping with unfavorable seasons and synchronizing their life cycles with host availability. In general, little is known about the seasonal cycles of insect ectoparasites of warm-blooded animals. The current study investigates the unusual phenology of a viviparous hippoboscid fly, the deer ked (Lipoptena cervi L.), that parasitizes boreal cervids. Despite months of asynchrony in offspring production, the adults emerge synchronously in mid-August across the northern boreal zone. We examined the role of diapause variation in the synchronization of life cycles by testing adult emergence success and time in relation to offspring birth month (October to April) and with respect to chilling time and photoperiod. Unexpectedly, we found that photoperiod had no role in regulating the life cycle, but diapause was maintained as long as pupae were exposed to cold. Pupae born before February needed a slightly longer exposure to high temperatures to terminate diapause if the cold period was short. Despite the apparent importance of a long period of chilling for life cycle synchrony, it was not required to terminate diapause. This finding of cold mainly preventing, rather than promoting, diapause termination is not novel among temperate insects, but it is rare. Slow diapause termination as a response to exceptionally long exposure to high, not low, temperatures seems to be a cornerstone for synchronizing the life cycle in the deer ked.

  11. Early Oligocene glaciation and productivity in the eastern equatorial Pacific: Insights into global carbon cycling

    NASA Astrophysics Data System (ADS)

    Coxall, Helen K.; Wilson, Paul A.

    2011-06-01

    The onset of sustained Antarctic glaciation across the Eocene-Oligocene transition (EOT) marks a pivotal change in Earth's climate, but our understanding of this event, particularly the role of the carbon cycle, is limited. To help address this gap we present the following paleoceanographic proxy records from Ocean Drilling Program Site 1218 in the eastern equatorial Pacific (EEP): (1) stable isotope (δ18O and δ13C) records generated in epifaunal benthic foraminifera (Cibicidoides spp.) to improve (double the resolution) the previously published records; (2) δ18O and δ13C records measured on Oridorsalis umbonatus, a shallow infaunal species; and (3) a record of benthic foraminifera accumulation rate (BFAR). Our new isotope data sets confirm the existence at Site 1218 of a two-step δ18O increase. They also lend support to the hypothesized existence of a late Eocene transient δ18O increase and early Oligocene Oi-1a and Oi-1b glacial maxima. Our record of BFAR indicates a transient (˜500 kyr) twofold to threefold peak relative to baseline Oligocene values associated with the onset of Antarctic glaciation that we attribute to enhanced biological export production in the EEP. This takes the same general form as the history of opal accumulation in the Southern Ocean, suggesting strong high-to-low-latitude oceanic coupling. These findings appear to lend support to the idea that the EOT δ13C excursion is traceable to increased organic carbon (Corg) burial. Paradoxically, early Oligocene sediments in the EEP are extremely Corg-poor, and proxy records of atmospheric pCO2 indicate a transient increase associated with the EOT.

  12. Scaling up food production in the Upper Mississippi river basin: modeling impacts on water quality and nutrient cycling

    NASA Astrophysics Data System (ADS)

    Bowen, E. E.; Martin, P. A.; Schuble, T. J.; Yan, E.; Demissie, Y.

    2010-12-01

    Agricultural production imposes significant environmental stress on the landscape, both in the intensity and extent of agricultural activities. Among the most significant impacts, agriculture dominates the natural reactive nitrogen cycle, with excess reactive nitrogen leading to the degraded quality of inland and coastal waters. In the U.S., policymakers and stakeholders nationwide continue to debate strategies for decreasing environmental degradation from agricultural lands. Such strategies aim to optimize the balance among competing demands for food, fuel and ecosystem services. One such strategy increasingly discussed in the national debate is that of localizing food production around urban areas, developing what some have recently called “foodsheds”. However, the environmental impacts of localizing food production around population centers are not well-understood given the hard-to-generalize variety seen in management practices currently employed among local farms marketing food crops directly to consumers. As a first, landscape level study of potential impacts from scaling up this type of agriculture, we use the USDA Soil and Water Assessment Tool (SWAT) model to quantify environmental impacts from developing foodsheds for all population centers in the Upper Mississippi river basin. Specifically, we focus on nutrient cycling and water quality impacts determining direct greenhouse gas emissions and changes to nutrient runoff from increased food production in this watershed. We investigate a variety of scenarios in which food production is scaled up to the regional level using different types of farm management practices, ranging from conventional production of fruits and vegetables, to production of these products from small-scale, diversified systems integrating conservation easements. In addition to impacts on nutrient cycling and water quality, we also characterize relative levels of productivity in conjunction with overall demand for food associated

  13. Pedaling power and speed production vs. technical factors and track difficulty in bicycle motocross cycling.

    PubMed

    Mateo, Manuel; Blasco-Lafarga, Cristina; Zabala, Mikel

    2011-12-01

    Mateo, M, Blasco-Lafarga, C, and Zabala, M. Pedaling power and speed production vs. technical factors and track difficulty in BMX cycling. J Strength Cond Res 25(12): 3248-3256, 2011-This article analyzes whether there is a determined profile in the production of cyclic and acyclic periods in relation to the phases of a bicycle motocross (BMX) race and whether this profile is related to the variables, Difficulty of track and Techniques used. After an initial test for determining maximum pedaling power (Pmax), 9 athletes belonging to the Spanish national team completed 3 series of 3 different types of races: (a) Complete track without pedaling; (b) Track, pedaling only at the gate start; and (c) track with free pedaling. The triple test was carried out over 3 days and on different level tracks: (a) high difficulty (HD), (b) medium difficulty (MD), and (c) low difficulty (LD). Our results show that average peak power applied in the BMX race was 85.21 ± 2.15% Pmax, coming down to 73.02 ± 18.38% at the gate start and to 51.37 ± 15.84% on the first straight. On the other hand, mean power (MP) in the BMX race is 33.79 ± 8.60% MPmax, with statistically significant differences in relation to the difficulty of the track (p < 0.000; 0.009; higher in the easiest). The mean velocity developed is 34.21 ± 1.0 km·h with significant differences (p < 0.000) in relation to the difficulty of the track. Acyclic efforts accounted for 86.3%, and cyclic efforts accounted for the remaining 16.7% of the overall performance in the race, with differences in relation to the difficulty of the track (p ≤ 0.003). Both power profile and performance (measured as velocity) are dependent on the phases and techniques of the race and are significantly affected by the level of difficulty of the track. The greater the technical level of the track, the lesser the possibility of developing cyclic power and vice versa. PMID:21804428

  14. Pedaling power and speed production vs. technical factors and track difficulty in bicycle motocross cycling.

    PubMed

    Mateo, Manuel; Blasco-Lafarga, Cristina; Zabala, Mikel

    2011-12-01

    Mateo, M, Blasco-Lafarga, C, and Zabala, M. Pedaling power and speed production vs. technical factors and track difficulty in BMX cycling. J Strength Cond Res 25(12): 3248-3256, 2011-This article analyzes whether there is a determined profile in the production of cyclic and acyclic periods in relation to the phases of a bicycle motocross (BMX) race and whether this profile is related to the variables, Difficulty of track and Techniques used. After an initial test for determining maximum pedaling power (Pmax), 9 athletes belonging to the Spanish national team completed 3 series of 3 different types of races: (a) Complete track without pedaling; (b) Track, pedaling only at the gate start; and (c) track with free pedaling. The triple test was carried out over 3 days and on different level tracks: (a) high difficulty (HD), (b) medium difficulty (MD), and (c) low difficulty (LD). Our results show that average peak power applied in the BMX race was 85.21 ± 2.15% Pmax, coming down to 73.02 ± 18.38% at the gate start and to 51.37 ± 15.84% on the first straight. On the other hand, mean power (MP) in the BMX race is 33.79 ± 8.60% MPmax, with statistically significant differences in relation to the difficulty of the track (p < 0.000; 0.009; higher in the easiest). The mean velocity developed is 34.21 ± 1.0 km·h with significant differences (p < 0.000) in relation to the difficulty of the track. Acyclic efforts accounted for 86.3%, and cyclic efforts accounted for the remaining 16.7% of the overall performance in the race, with differences in relation to the difficulty of the track (p ≤ 0.003). Both power profile and performance (measured as velocity) are dependent on the phases and techniques of the race and are significantly affected by the level of difficulty of the track. The greater the technical level of the track, the lesser the possibility of developing cyclic power and vice versa.

  15. Production and Cycling of Methylated Mercury Species in Arctic Marine Waters

    NASA Astrophysics Data System (ADS)

    Lehnherr, I.; St. Louis, V. L.; Hintelmann, H.

    2009-12-01

    Monomethyl mercury (MMHg), a vertebrate neurotoxin which bioaccumulates through foodwebs, is found in some Arctic marine mammals at levels that may be harmful to northern peoples consuming them as food. Unfortunately, sources of MMHg to polar marine food webs remain unknown, in part due to the complex nature of Hg cycling in polar marine waters. Since 2005, we have been sampling the marine waters of the Canadian Arctic Archipelago from the Canadian Coast Guard research icebreaker CCGS Amundsen. Early results demonstrated that elevated concentrations of both MMHg and dimethyl mercury (DMHg, a toxic, gaseous Hg species) are found in sub-surface Arctic marine waters (89±36 pg L-1 and 73±37 pg L-1, respectively) despite low total Hg (THg) concentrations (290±220 pg L-1), suggesting an internal source of methylated Hg. We tested the hypothesis that methylated Hg species are produced directly in the marine water column using stable-isotope Hg tracers. Seawater samples were amended with 198Hg(II) and incubated for 0, 8, 16 or 24 hours to measure the production of MM198Hg, DM198Hg and gaseous elemental 198Hg(0) (GEM) over time. A second tracer, MM199Hg, was also added to quantify MMHg methylation (formation of DM199Hg), demethylation (loss of MM199Hg) and reduction (formation of 199Hg(0)). Preliminary analysis of the data indicates that Hg(II) is methylated in polar marine waters to form both MMHg (first order rate-constant km1 ~6x10-4 d-1) and DMHg (km2 ~5x10-6 d-1). We also found that DMHg production from MMHg is ~50x faster than with Hg(II) as the substrate. Furthermore, at a small number of sites, we measured methylation rates that were elevated by almost a full order of magnitude compared to the average, suggesting that methylation hotspots may exist in Arctic marine waters. However, during the less productive fall season when the CCGS Amundsen cruises were conducted, demethylation of MMHg generally appears to dominate in the water column and can occur via a number

  16. Activities with Argentina. Spring 1999. A U.S. Department of Energy Cooperative Program with the National Atomic Energy Commission of the Argentine Republic

    SciTech Connect

    1999-06-01

    In 1989, the US Department of Energy (DOE) responded to the need to redirect resources from weapons production to environmental restoration and waste management by establishing the Office of Environmental Management (EM) and delegated to this office the responsibility of cleaning up the US nuclear weapons complex. Now in its eight year, EM`s mission has three central facets: (1) to assess, remediate, and monitor contaminated sites and facilities; (2) to store, treat, and dispose of waste from past and current operations; and (3) to develop and implement innovative technologies for environmental cleanup. To this end, EM has established domestic and international cooperative technology development programs, including one with the Republic of Argentina. Cooperating with Argentine scientific institutes and industries meets US cleanup objectives by: (1) identifying and accessing Argentine EM-related technologies, thereby leveraging investments and providing cost-savings; (2) improving access to technical information, scientific expertise, and technologies applicable to EM needs; and (3) fostering the development of innovative environmental technologies by increasing US private sector opportunities in Argentina in EM-related areas.

  17. Comparative study of spawning pattern and reproductive potential of the Northern and Southern stocks of Argentine hake (Merluccius hubbsi)

    NASA Astrophysics Data System (ADS)

    Rodrigues, Karina A.; Macchi, Gustavo J.; Militelli, Maria I.

    2015-08-01

    The reproductive biology of the Northern (Bonaerense) and Southern (Patagonian) stocks of Merluccius hubbsi in the Argentinean Sea is analyzed, including information on spawning areas, estimates of abundance and size composition of spawning females, fecundity, spawning frequency and egg quality. Samples of Argentine hake were obtained during the period of peak reproductive activity; May and January for the Northern and Southern stocks, respectively. The size of the reproductive area for the Northern stock (35-38°S) was clearly smaller than the one estimated for the Southern population (43°30‧-46°S), being 23,770 km2 and 52,460 km2 respectively. Spawning females from the Northern reproductive area were smaller (modal values between 35 and 40 cm TL) than those from the Southern stock (modal values between 38 and 50 cm TL), and they were also less abundant in number and had a lower spawning frequency (8-13 days and 5-7 days between partial spawning for the Northern and Southern stocks respectively). No differences in batch and relative fecundity between stocks were recorded (mean values of 526 and 530 hydrated oocytes g- 1), but the dry weights of hydrated oocytes from females of the Northern group were higher (3.08 mg for 100 hydrated oocytes) than those of the Patagonian stock (2.84 mg) for the same total length range. The egg production during the month of peak spawning of the Northern group depended mostly on the smaller females (< 50 cm TL) and was in average 1 to 2 orders of magnitude lower than that estimated for the Southern stock (9 × 1012-22 × 1012 eggs and 692 × 1012-1295 × 1012 eggs for the Northern and Southern stocks respectively). Those differences in egg production and the high productivity and retentive characteristics described for the spawning area and nursery ground in Patagonian waters would justify the greater abundance and resilience of the Southern stock of Argentine hake. The low abundance of females in spawning capable stage observed

  18. A thermochemical data bank for cycle analysis. [water decomposition for hydrogen production

    NASA Technical Reports Server (NTRS)

    Carty, R.; Funk, J.; Conger, W.; Soliman, M.; Cox, K.

    1976-01-01

    The use of the computer program PAC-2 to produce a thermodynamic data bank for various materials used in water-splitting cycles is described. The sources of raw data and a listing of 439 materials for which data are presently available are presented. This paper also discusses the use of the data bank in conjunction with two other programs, CEC-72 and HYDRGN. The integration of these three programs implement an evaluation procedure for thermochemical water splitting cycles. CEC-72 is a program used to predict the equilibrium composition of the various chemical reactions in the cycle. HYDRGN is a program which is used to calculate changes in thermodynamic properties, work of separation, amount of recycle, internal heat regeneration, total thermal energy and process thermal efficiency for a thermochemical cycle.

  19. Pravastatin induces cell cycle arrest and decreased production of VEGF and bFGF in multiple myeloma cell line.

    PubMed

    Trojan, P J J; Bohatch-Junior, M S; Otuki, M F; Souza-Fonseca-Guimarães, F; Svidnicki, P V; Nogaroto, V; Fernandes, D; Krum, E A; Favero, G M

    2016-02-01

    Multiple myeloma (MM) is a B cell bone marrow neoplasia characterized by inflammation with an intense secretion of growth factors that promote tumor growth, cell survival, migration and invasion. The aim of this study was to evaluate the effects of pravastatin, a drug used to reduce cholesterol, in a MM cell line.Cell cycle and viability were determinate by Trypan Blue and Propidium Iodide. IL6, VEGF, bFGF and TGFβ were quantified by ELISA and qRT-PCR including here de HMG CoA reductase. It was observed reduction of cell viability, increase of cells in G0/G1 phase of the cell cycle and reducing the factors VEGF and bFGF without influence on 3-Methyl-Glutaryl Coenzyme A reductase expression.The results demonstrated that pravastatin induces cell cycle arrest in G0/G1 and decreased production of growth factors in Multiple Myeloma cell line. PMID:26909624

  20. Solar Cycle Effects on the Heliospheric Interface and Related Energetic Neutral Atom Production

    NASA Astrophysics Data System (ADS)

    Pogorelov, N. V.; Heerikhuisen, J.; Borovikov, S.; Ebert, R. W.; Suess, S. T.; Zank, G. P.

    2013-05-01

    Solar cycle has a profound influence on the solar wind (SW) interaction with the local interstellar medium (LISM) on more than one time scales. Also, there are substantial differences in individual solar cycle lengths and SW behavior within them. The presence of a slow SW belt, with a variable latitudinal extent changing within each solar cycle from rather small angles to 90 degrees, separated from the fast wind that originates at coronal holes substantially affects plasma at the heliospheric interface, in the compressed plasma layers ahead of and behind the heliopause. The solar cycle may be the reason of the complicated flow structure being observed in the inner heliosheath by Voyager 1. We present the results of the solar cycle simulations based on different numerical models, including the model with the SW boundary conditions derived from Ulysses measurements, and demonstrate how they can explain the observations of small to negative SW radial velocity components at Voyager 1, as well as an abrupt decrease in the ACR flux. Related changes in the ENA flux throughout the solar cycle are also discussed in the context of IBEX measurements.

  1. Long-term field trial to control the invasive Argentine ant (Hymenoptera: Formicidae) with synthetic trail pheromone.

    PubMed

    Nishisue, K; Sunamura, E; Tanaka, Y; Sakamoto, H; Suzuki, S; Fukumoto, T; Terayama, M; Tatsuki, S

    2010-10-01

    Previous short-term experiments showed that trail following behavior of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), can be disrupted by a high concentration of synthetic trail pheromone component (Z)-9-hexadecenal. In this study, a long-term field trial was conducted in 100-m2 plots of house gardens in an urban area of Japan to see whether the control effect on Argentine ants can be obtained by permeating synthetic trail pheromone from dispensers. The dispensers were placed in the experimental plots during the ant's active season (April-November) for 2 yr with monthly renewal. To estimate Argentine ant population density, foraging activity of Argentine ants in the study plots was monitored by monthly bait surveys. Throughout the study period, Argentine ant foraging activity was suppressed in the presence of the dispensers, presumably via trail forming inhibition. In contrast, the level of foraging activity was not different between treatment and no-treatment plots when the dispensers were temporarily removed, suggesting that treatment with pheromone dispensers did not suppress Argentine ant density in the treatment plots. Population decline may be expected with larger-scale treatment that covers a significant portion of the ant colony or with improvement in the potency of the disruptant. PMID:21061980

  2. Use of a small molecule cell cycle inhibitor to control cell growth and improve specific productivity and product quality of recombinant proteins in CHO cell cultures

    PubMed Central

    Du, Zhimei; Treiber, David; McCarter, John D; Fomina-Yadlin, Dina; Saleem, Ramsey A; McCoy, Rebecca E; Zhang, Yuling; Tharmalingam, Tharmala; Leith, Matthew; Follstad, Brian D; Dell, Brad; Grisim, Brent; Zupke, Craig; Heath, Carole; Morris, Arvia E; Reddy, Pranhitha

    2015-01-01

    The continued need to improve therapeutic recombinant protein productivity has led to ongoing assessment of appropriate strategies in the biopharmaceutical industry to establish robust processes with optimized critical variables, that is, viable cell density (VCD) and specific productivity (product per cell, qP). Even though high VCD is a positive factor for titer, uncontrolled proliferation beyond a certain cell mass is also undesirable. To enable efficient process development to achieve consistent and predictable growth arrest while maintaining VCD, as well as improving qP, without negative impacts on product quality from clone to clone, we identified an approach that directly targets the cell cycle G1-checkpoint by selectively inhibiting the function of cyclin dependent kinases (CDK) 4/6 with a small molecule compound. Results from studies on multiple recombinant Chinese hamster ovary (CHO) cell lines demonstrate that the selective inhibitor can mediate a complete and sustained G0/G1 arrest without impacting G2/M phase. Cell proliferation is consistently and rapidly controlled in all recombinant cell lines at one concentration of this inhibitor throughout the production processes with specific productivities increased up to 110 pg/cell/day. Additionally, the product quality attributes of the mAb, with regard to high molecular weight (HMW) and glycan profile, are not negatively impacted. In fact, high mannose is decreased after treatment, which is in contrast to other established growth control methods such as reducing culture temperature. Microarray analysis showed major differences in expression of regulatory genes of the glycosylation and cell cycle signaling pathways between these different growth control methods. Overall, our observations showed that cell cycle arrest by directly targeting CDK4/6 using selective inhibitor compound can be utilized consistently and rapidly to optimize process parameters, such as cell growth, qP, and glycosylation profile in

  3. Advanced glycation end products are mitogenic signals and trigger cell cycle reentry of neurons in Alzheimer's disease brain.

    PubMed

    Kuhla, Angela; Ludwig, Sophie C; Kuhla, Björn; Münch, Gerald; Vollmar, Brigitte

    2015-02-01

    Neurons that reenter the cell cycle die rather than divide, a phenomenon that is associated with neurodegeneration in Alzheimer's disease (AD). Reexpression of cell-cycle related genes in differentiated neurons in AD might be rooted in aberrant mitogenic signaling. Because microglia and astroglia proliferate in the vicinity of amyloid plaques, it is likely that plaque components or factors secreted from plaque-activated glia induce neuronal mitogenic signaling. Advanced glycation end products (AGEs), protein-bound oxidation products of sugar, might be one of those mitogenic compounds. Cyclin D1 positive neurons are colocalized with AGEs or directly surrounded by extracellular AGE deposits in AD brain. However, a direct proof of DNA replication in these cells has been missing. Here, we report by using fluorescent in situ hybridization that consistent with the expression of cell cycle proteins, hyperploid neuronal cells are in colocalization with AGE staining in AD brains but not in nondemented controls. To complement human data, we used apolipoprotein E-deficient mice as model of neurodegeneration and showed that increased oxidative stress caused an intensified neuronal deposition of AGEs, being accompanied by an activation of the MAPK cascade via RAGE. This cascade, in turn, induced the expression of cyclin D1 and DNA replication. In addition, reduction of oxidative stress by application of α-lipoic acid decreased AGE accumulations, and this decrease was accompanied by a reduction in cell cycle reentry and a more euploid neuronal genome.

  4. Metabolic engineering in the biotechnological production of organic acids in the tricarboxylic acid cycle of microorganisms: Advances and prospects.

    PubMed

    Yin, Xian; Li, Jianghua; Shin, Hyun-Dong; Du, Guocheng; Liu, Long; Chen, Jian

    2015-11-01

    Organic acids, which are chemically synthesized, are also natural intermediates in the metabolic pathways of microorganisms, among which the tricarboxylic acid (TCA) cycle is the most crucial route existing in almost all living organisms. Organic acids in the TCA cycle include citric acid, α-ketoglutaric acid, succinic acid, fumaric acid, l-malic acid, and oxaloacetate, which are building-block chemicals with wide applications and huge markets. In this review, we summarize the synthesis pathways of these organic acids and review recent advances in metabolic engineering strategies that enhance organic acid production. We also propose further improvements for the production of organic acids with systems and synthetic biology-guided metabolic engineering strategies.

  5. The purine nucleotide cycle. A pathway for ammonia production in the rat kidney.

    PubMed Central

    Bogusky, R T; Lowenstein, L M; Lowenstein, J M

    1976-01-01

    Particle-free extracts prepared from kidney cortex of rat catalyze the formation of ammonia via the purine nucleotide cycle. The cycle generates ammonia and fumarate from aspartate, using catalytic amounts of inosine monophosphate, adenylosuccinate, and adenosine monophosphate. The specific activities of the enzymes of the cycle are 1.27+/-0.27 nmol/mg protein per min (SE) for adenoylosuccinate synthetase, 1.38+/-0.16 for adenylosuccinase, and 44.0+/-3.3 for AMP deaminase. Compared with controls, extracts prepared from kidneys of rats fed ammonium chloride for 2 days show a 60% increase in adenylosuccinate synthetase and a threefold increase in adenylosuccinase activity, and a greater and more rapid synthesis of ammonia and adenine nucleotide from aspartate and inosine monophosphate. Extracts prepared from kidneys of rats fed a potassium-deficient diet show a twofold increase in adenylosuccinate synthetase and a threefold increase in adenylosuccinase activity. In such extracts the rate of synthesis of ammonia and adenine nucleotide from aspartate and inosine monophosphate is also increased. These results show that the reactions of the purine nucleotide cycle are present and can operate in extracts of kidney cortex. The operational capacity of the cycle is accelerated by ammonium chloride feeding and potassium depletion, conditions known to increase renal ammonia excretion. Extracts of kidney cortex convert inosine monophosphate to uric acid. This is prevented by addition of allopurinol of 1-pyrophosphoryl ribose 5-phosphate to the reaction mixture. PMID:821968

  6. Levelized life-cycle costs for four residue-collection systems and four gas-production systems

    SciTech Connect

    Thayer, G.R.; Rood, P.L.; Williamson, K.D. Jr.; Rollett, H.

    1983-01-01

    Technology characterizations and life-cycle costs were obtained for four residue-collection systems and four gas-production systems. All costs are in constant 1981 dollars. The residue-collection systems were cornstover collection, wheat-straw collection, soybean-residue collection, and wood chips from forest residue. The life-cycle costs ranged from $19/ton for cornstover collection to $56/ton for wood chips from forest residues. The gas-production systems were low-Btu gas from a farm-size gasifier, solar flash pyrolysis of biomass, methane from seaweed farms, and hydrogen production from bacteria. Life-cycle costs ranged from $3.3/10/sup 6/ Btu for solar flash pyrolysis of biomass to $9.6/10/sup 6/ Btu for hydrogen from bacteria. Sensitivity studies were also performed for each system. The sensitivity studies indicated that fertilizer replacement costs were the dominate costs for the farm-residue collection, while residue yield was most important for the wood residue. Feedstock costs were most important for the flash pyrolysis. Yields and capital costs are most important for the seaweed farm and the hydrogen from bacteria system.

  7. Climatic and management drivers of CO2 exchanges by a production crop: analysis over three successive 4-year cycles.

    NASA Astrophysics Data System (ADS)

    Buysse, Pauline; Moureaux, Christine; Bodson, Bernard; Aubinet, Marc

    2016-04-01

    Carbon dioxide (CO2) exchanges between crops and the atmosphere are influenced by both climatic and crop management drivers. The investigated crop, situated at the Lonzée Terrestrial Observatory (candidate ICOS site) in the Hesbaye region in Belgium and managed for more than 70 years using conventional farming practices, was monitored over three complete sugar beet/winter wheat/potato/winter wheat rotation cycles from 2004 to 2016. Eddy covariance, automatic and manual soil chambers, leaf diffusion and biomass measurements were performed continuously in order to obtain the daily and seasonal Net Ecosystem Exchange (NEE), Gross Primary Productivity (GPP), total Ecosystem Respiration (TER), Net Primary Productivity (NPP), autotrophic respiration, heterotrophic respiration and Net Biome Production (NBP). Meteorological data and crop management practices were also recorded. Climatic and seasonal evolutions of the carbon balance components were studied and crop carbon budgets were computed both at the yearly and crop rotation cycle scales. On average over the 12 years, NEE was negative but NBP was positive, i.e. as far as carbon exportation by harvest are included in the budget, the site behaved as a carbon source. Impacts of both meteorological drivers and crop management operations on CO2 exchanges were analyzed and compared between crop types, years, and rotation cycles. The uncertainties associated to the carbon fluxes were also evaluated and discussed.

  8. Phytoplankton versus macrophyte contribution to primary production and biogeochemical cycles of a coastal mesotidal system. A modelling approach

    NASA Astrophysics Data System (ADS)

    Plus, M.; Auby, I.; Maurer, D.; Trut, G.; Del Amo, Y.; Dumas, F.; Thouvenin, B.

    2015-11-01

    This study presents an assessment of the contributions of various primary producers to the global annual production and N/P cycles of a coastal system, namely the Arcachon Bay, by means of a numerical model. This 3D model fully couples hydrodynamic with ecological processes and simulates nitrogen, silicon and phosphorus cycles as well as phytoplankton, macroalgae and seagrasses. Total annual production rates for the different components were calculated for different years (2005, 2007 and 2009) during a time period of drastic reduction in seagrass beds since 2005. The total demand of nitrogen and phosphorus was also calculated and discussed with regards to the riverine inputs. Moreover, this study presents the first estimation of particulate organic carbon export to the adjacent open ocean. The calculated annual net production for the Arcachon Bay (except microphytobenthos, not included in the model) ranges between 22,850 and 35,300 tons of carbon. The main producers are seagrasses in all the years considered with a contribution ranging from 56% to 81% of global production. According to our model, the -30% reduction in seagrass bed surface between 2005 and 2007, led to an approximate 55% reduction in seagrass production, while during the same period of time, macroalgae and phytoplankton enhanced their productions by about +83% and +46% respectively. Nonetheless, the phytoplankton production remains about eightfold higher than the macroalgae production. Our results also highlight the importance of remineralisation inside the Bay, since riverine inputs only fulfill at maximum 73% nitrogen and 13% phosphorus demands during the years 2005, 2007 and 2009. Calculated advection allowed a rough estimate of the organic matter export: about 10% of the total production in the bay was exported, originating mainly from the seagrass compartment, since most of the labile organic matter was remineralised inside the bay.

  9. Survey of Argentine Health Researchers on the Use of Evidence in Policymaking

    PubMed Central

    Corluka, Adrijana; Hyder, Adnan A.; Segura, Elsa; Winch, Peter; McLean, Robert K. D.

    2015-01-01

    Objective In this study, Argentine health researchers were surveyed regarding their perceptions of facilitators and barriers to evidence-based policymaking in Argentina, as well as their publication activities, and research environment satisfaction. Methods A self-administered online survey was sent to health researchers in Argentina. The survey questions were based on a preceding qualitative study of Argentine health researchers, as well as the scientific literature. Results Of the 647 researchers that were reached, 226 accessed the survey, for a response rate of 34.9%. Over 80% of researchers surveyed had never been involved in or contributed to decision-making, while over 90% of researchers indicated they would like to be involved in the decision-making process. Decision-maker self-interest was perceived to be the driving factor in the development of health and healthcare policies. Research conducted by a research leader was seen to be the most influential factor in influencing health policy, followed by policy relevance of the research. With respect to their occupational environment, researchers rated highest and most favourably the opportunities available to present, discuss and publish research results and their ability to further their education and training. Argentine researchers surveyed demonstrated a strong interest and willingness to contribute their work and expertise to inform Argentine health policy development. Conclusion Despite Argentina’s long scientific tradition, there are relatively few institutionalized linkages between health research results and health policymaking. Based on the results of this study, the disconnect between political decision-making and the health research system, coupled with fewer opportunities for formalized or informal researcher/decision-maker interaction, contribute to the challenges in evidence informing health policymaking in Argentina. Improving personal contact and the building of relationships between

  10. Toxicity and repellency of borate-sucrose water baits to Argentine ants (Hymenoptera: Formicidae).

    PubMed

    Klotz, J H; Greenberg, L; Amrhein, C; Rust, M K

    2000-08-01

    The oral toxicity of boron compounds to the Argentine ant, Linepithema humile (Mayr), was evaluated in laboratory tests. The ants were provided 25% sucrose water containing 0.5 and 1% boric acid, disodium octaborate tetrahydrate, and borax. Lethal times of these solutions were a function of the concentration of boron. In field tests, the ants showed no discrimination between disodium octaborate tetrahydrate and boric acid. There was a significant reduction in consumption of sucrose water with > 1% boric acid.

  11. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOEpatents

    Cassano, A.A.

    1985-07-02

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs. 3 figs.

  12. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOEpatents

    Cassano, Anthony A.

    1985-01-01

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs.

  13. Disinfection byproduct formation during biofiltration cycle: Implications for drinking water production.

    PubMed

    Delatolla, R; Séguin, C; Springthorpe, S; Gorman, E; Campbell, A; Douglas, I

    2015-10-01

    The goal of this study was to investigate the potential of biofiltration to reduce the formation potential of disinfection byproducts (DBPs). Particularly, the work investigates the effect of the duration of the filter cycle on the formation potential of total trihalomethanes (TTHM) and five species of haloacetic acids (HAA5), dissolved oxygen (DO), organic carbon, nitrogen and total phosphorous concentrations along with biofilm coverage of the filter media and biomass viability of the attached cells. The study was conducted on a full-scale biologically active filter, with anthracite and sand media, at the Britannia water treatment plant (WTP), located in Ottawa, Ontario, Canada. The formation potential of both TTHMs and HAA5s decreased due to biofiltration. However the lowest formation potentials for both groups of DBPs and or their precursors were observed immediately following a backwash event. Hence, the highest percent removal of DBPs was observed during the early stages of the biofiltration cycle, which suggests that a higher frequency of backwashing will reduce the formation of DBPs. Variable pressure scanning electron microscopy (VPSEM) analysis shows that biofilm coverage of anthracite and sand media increases as the filtration cycle progressed, while biomass viability analysis demonstrates that the percentage of cells attached to the anthracite and sand media also increases as the filtration cycle progresses. These results suggest that the development and growth of biofilm on the filters increases the DPB formation potential.

  14. The Development of Terrestrial Water Cycle Applications for SMAP Soil Moisture Data Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil moisture storage sits at the locus of the terrestrial water cycle and governs the relative partitioning of precipitation into various land surface flux components. Consequently, improved observational constraint of soil moisture variations should improve our ability to globally monitor the te...

  15. Life cycle environmental and economic tradeoffs of using fast pyrolysis products for power generation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bio-oils produced from small-scale pyrolysis technology may have economic and environmental benefits for both densifying agricultural biomass and supplying local bio-energy markets (e.g., Renewable Portfolio Standards). This study presents a life cycle assessment (LCA) of a farm-scale bio-oil produ...

  16. Reactive oxygen species production and antioxidant enzyme expression after Epstein-Barr virus lytic cycle induction in Raji cell line.

    PubMed

    Gargouri, Bochra; Nasr, Rihab; ben Mansour, Riadh; Lassoued, Saloua; Mseddi, Malek; Attia, Hammadi; El Feki, Abd el Fatteh; Van Pelt, Jos

    2011-12-01

    In a previous study, we have described oxidative stress during Epstein-Barr virus lytic cycle induction. Oxidative stress was evidenced by the observed high MDA levels and the decreased activities of antioxidant enzymes. We hypothesised that the lower activities of the antioxidant enzymes decrease were the result of either the excessive production of reactive oxygen radical species (ROS) or a negative regulation of the antioxidant enzyme gene expressions. In an attempt to clarify this situation, EBV lytic cycle was induced in Raji cell line by a non-stressing dose of 12-0-tetradecanoylphorbol-13-acetate. BZLF-1, superoxide dismutase, and catalase gene expressions were then analysed using semi-quantitative RT-PCR, simultaneously at a kinetic of 6, 12, 24, 36, and 48 h. ROS production was evaluated by chemiluminescence. A study was conducted to establish whether ROS production, BZLF-1, and the expression of antioxidant genes were inter-correlated. Induction of the lytic cycle resulted in increased expressions of the genes of superoxide dismutase and catalase, which began at 24 h (p < 0.05) and reached a peak at 48 h (p < 0.05). Significant increases of the ROS levels were observed in TPA-treated Raji cell line at 12 h, as compared with untreated cells, reaching a peak at 48 h after EBV lytic cycle induction. ROS production correlates positively with BZLF-1, SOD, and CAT gene expressions (p < 0.05; r = 0.913, r = 0.978, and r = 0.955, respectively). A positive correlation was also observed between BZLF-1 and antioxidant gene expressions (p < 0.05; r = 0.961 and r = 0.987, respectively). In conclusion, the observed increases of the SOD and CAT gene expressions eliminate the hypothesis of a repression of the respective genes during the induction of the lytic cycle. On the other hand, the observed direct correlation between the BZLF-1 gene expression and the ROS production is indicative of a role of this gene in oxidative stress.

  17. Prebiotic Metabolism: Production by Mineral Photoelectrochemistry of α-Ketocarboxylic Acids in the Reductive Tricarboxylic Acid Cycle

    NASA Astrophysics Data System (ADS)

    Guzman, Marcelo I.; Martin, Scot T.

    2009-11-01

    A reductive tricarboxylic acid (rTCA) cycle could have fixed carbon dioxide as bio chemically useful energy-storage molecules on early Earth. Nonenzymatic chemical pathways for some steps of the rTCA cycle, however, such as the production of the α-ketocarboxylic acids pyruvate and α-ketoglutarate, remain a challenging problem for the viability of the proposed prebiotic cycle. As a class of compounds, α-ketocarboxylic acids have high free energies of formation that disfavor their production. We report herein the production of pyruvate from lactate and of α-ketoglutarate from pyruvate in the millimolar concentration range as promoted by ZnS mineral photoelectrochemistry. Pyruvate is produced from the photooxidation of lactate with 70% yield and a quantum efficiency of 0.009 at 15°C across the wavelength range of 200-400 nm. The produced pyruvate undergoes photoreductive back reaction to lactate at a 30% yield and with a quantum efficiency of 0.0024. Pyruvate alternatively continues in photooxidative forward reaction to α-ketoglutarate with a 50% yield and a quantum efficiency of 0.0036. The remaining 20% of the carbon follows side reactions that produce isocitrate, glutarate, and succinate. Small amounts of acetate are also produced. The results of this study suggest that α-ketocarboxylic acids produced by mineral photoelectrochemistry could have participated in a viable enzyme-free cycle for carbon fixation in an environment where light, sulfide minerals, carbon dioxide, and other organic compounds interacted on prebiotic Earth.

  18. The seminiferous epithelium cycle and daily spermatic production in the adult maned wolf (Chrysocyon brachyurus, Illiger, 1811).

    PubMed

    Bitencourt, Viviane Lewicki; de Paula, Tarcízio Antônio Rego; da Matta, Sérgio Luis Pinto; Fonseca, Cláudio César; dos Anjos Benjamin, Laércio; Costa, Deiler Sampaio

    2007-01-01

    The duration of the seminiferous epithelium cycle was estimated in adult maned wolves (Chrysocyon brachyurus, Illiger, 1811), by applying intratesticular injections with tritiated thymidine. The total duration of the seminiferous epithelium cycle in this species was calculated in 8.99 days. So, taking into account that approximately 4.5 cycles of the seminiferous epithelium are necessary for the whole spermatogenesis process to complete, the production of spermatozoa from one spermatogonia will take about 40.45 days. The duration of the spermiogenesis was calculated to be 12.3 days. The eight stages of the seminiferous epithelium cycle were described by the tubular morphology method, which is based either on the form and position of the spermatid nuclei and the occurrence of meiotic divisions. The values of the relative frequency for the pre-meiotic, meiotic and post-meiotic phases in this species were 3.5, 0.78 and 4.8 days, respectively. The maned wolf produces about 29 million spermatozoa a day for each testis gram, therefore being classified among the species provided with a high spermatogenetic efficiency.

  19. Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production

    NASA Astrophysics Data System (ADS)

    Al-Sulaiman, Fahad A.; Dincer, Ibrahim; Hamdullahpur, Feridun

    The study examines a novel system that combined a solid oxide fuel cell (SOFC) and an organic Rankine cycle (ORC) for cooling, heating and power production (trigeneration) through exergy analysis. The system consists of an SOFC, an ORC, a heat exchanger and a single-effect absorption chiller. The system is modeled to produce a net electricity of around 500 kW. The study reveals that there is 3-25% gain on exergy efficiency when trigeneration is used compared with the power cycle only. Also, the study shows that as the current density of the SOFC increases, the exergy efficiencies of power cycle, cooling cogeneration, heating cogeneration and trigeneration decreases. In addition, it was shown that the effect of changing the turbine inlet pressure and ORC pump inlet temperature are insignificant on the exergy efficiencies of the power cycle, cooling cogeneration, heating cogeneration and trigeneration. Also, the study reveals that the significant sources of exergy destruction are the ORC evaporator, air heat exchanger at the SOFC inlet and heating process heat exchanger.

  20. Using Market Forces to Reduce Greenhouse Gas Emissions Through Product-Level Life Cycle Analysis and Eco-Labeling

    NASA Astrophysics Data System (ADS)

    Sweeney, J. F.; Davis, S. J.

    2007-12-01

    Established protocols allow entity-level accounting of greenhouse gas (GHG) emissions. The information contained within GHG inventories is used by entities to manage their carbon footprint and to anticipate future exposure to compulsory GHG markets or taxes. The efficacy of such inventories, as experienced by the consumer, can be improved upon by product-level GHG inventories applying the methods of traditional life cycle analysis (LCA). A voluntary product-level assessment of this type, coupled with an eco-label, would 1) empower consumers with information about the total embodied GHG content of a product, 2) allow companies to understand and manage GHG emissions outside the narrow scope of their entities, and 3) drive reduction of GHG emissions throughout product value chains. The Climate Conservancy (TCC) is a non-profit organization founded to help companies calculate their GHG emissions at the level of individual product units, and to inform consumers about the GHG intensity of the products they choose to purchase. With the assistance of economists, policy experts and scientists, TCC has developed a useful metric for reporting product-level GHG emissions that allows for a normalized comparison of a product's GHG intensity irrespective of industry sector or competitors, where GHG data are often unavailable or incomplete. Using this metric, we envision our Climate Conscious label becoming an important arbiter of choice for consumers seeking ways to mitigate their climate impacts without the need for governmental regulation.

  1. Modeling cumulative effects in life cycle assessment: the case of fertilizer in wheat production contributing to the global warming potential.

    PubMed

    Laratte, Bertrand; Guillaume, Bertrand; Kim, Junbeum; Birregah, Babiga

    2014-05-15

    This paper aims at presenting a dynamic indicator for life cycle assessment (LCA) measuring cumulative impacts over time of greenhouse gas (GHG) emissions from fertilizers used for wheat cultivation and production. Our approach offers a dynamic indicator of global warming potential (GWP), one of the most used indicator of environmental impacts (e.g. in the Kyoto Protocol). For a case study, the wheat production in France was selected and considered by using data from official sources about fertilizer consumption and production of wheat. We propose to assess GWP environmental impact based on LCA method. The system boundary is limited to the fertilizer production for 1 ton of wheat produced (functional unit) from 1910 to 2010. As applied to wheat production in France, traditional LCA shows a maximum GWP impact of 500 kg CO2-eq for 1 ton of wheat production, whereas the GWP impact of wheat production over time with our approach to dynamic LCA and its cumulative effects increases to 18,000 kg CO2-eq for 1 ton of wheat production. In this paper, only one substance and one impact assessment indicator are presented. However, the methodology can be generalized and improved by using different substances and indicators.

  2. Modeling cumulative effects in life cycle assessment: the case of fertilizer in wheat production contributing to the global warming potential.

    PubMed

    Laratte, Bertrand; Guillaume, Bertrand; Kim, Junbeum; Birregah, Babiga

    2014-05-15

    This paper aims at presenting a dynamic indicator for life cycle assessment (LCA) measuring cumulative impacts over time of greenhouse gas (GHG) emissions from fertilizers used for wheat cultivation and production. Our approach offers a dynamic indicator of global warming potential (GWP), one of the most used indicator of environmental impacts (e.g. in the Kyoto Protocol). For a case study, the wheat production in France was selected and considered by using data from official sources about fertilizer consumption and production of wheat. We propose to assess GWP environmental impact based on LCA method. The system boundary is limited to the fertilizer production for 1 ton of wheat produced (functional unit) from 1910 to 2010. As applied to wheat production in France, traditional LCA shows a maximum GWP impact of 500 kg CO2-eq for 1 ton of wheat production, whereas the GWP impact of wheat production over time with our approach to dynamic LCA and its cumulative effects increases to 18,000 kg CO2-eq for 1 ton of wheat production. In this paper, only one substance and one impact assessment indicator are presented. However, the methodology can be generalized and improved by using different substances and indicators. PMID:24631622

  3. The Haleakala Argentine ant project: a synthesis of past research and prospects for the future.

    USGS Publications Warehouse

    Krushelnycky, Paul; Haines, William; Loope, Lloyd; Van Gelder, Ellen

    2011-01-01

    1. The Haleakala Argentine Ant Project is an ongoing effort to study the ecology of the invasive Argentine ant in the park, and if possible to develop a strategy to control this destructive species. 2. Past research has demonstrated that the Argentine ant causes very significant impacts on native arthropods where it invades, threatening a large portion of the park’s biodiversity in subalpine shrubland and alpine aeolian ecosystems. 3. Patterns of spread over the past 30+ years indicate that the invasion process is influenced to a substantial degree by abiotic factors such as elevation, rainfall and temperature, and that the ant has not reached its potential range. Predictions of total range in the park suggest that it has only invaded a small fraction of available suitable habitat, confirming that this species is one of most serious threats to the park’s natural resources. 4. Numerous experiments have been conducted since 1994 in an attempt to develop a method for eradicating the Argentine ant at Haleakala using pesticidal ant baits. Thirty baits have been screened for attractiveness to ants in the park, and ten of these were tested for effectiveness of control in field plots. While some of these baits have been very effective in reducing numbers of ants, none has been able to eliminate all nests in experimental plots. 5. Research into a secondary management goal of ant population containment was initiated in 1996. By treating only expanding margins of the park’s two ant populations with an ant pesticide, rates of outward spread were substantially reduced in some areas. While this strategy was implemented from 1997 to 2004, it was ultimately discontinued after 2004 because of the difficulty and insufficient effectiveness of the technique. 6. In order to achieve the types of results necessary for eradication, the project would probably need to explore the possibility of developing a specialized bait, rather than relying on a commercially produced bait. An

  4. Hydrogen production by water decomposition using a combined electrolytic-thermochemical cycle

    NASA Technical Reports Server (NTRS)

    Farbman, G. H.; Brecher, L. E.

    1976-01-01

    A proposed dual-purpose power plant generating nuclear power to provide energy for driving a water decomposition system is described. The entire system, dubbed Sulfur Cycle Water Decomposition System, works on sulfur compounds (sulfuric acid feedstock, sulfur oxides) in a hybrid electrolytic-thermochemical cycle; performance superior to either all-electrolysis systems or presently known all-thermochemical systems is claimed. The 3345 MW(th) graphite-moderated helium-cooled reactor (VHTR - Very High Temperature Reactor) generates both high-temperature heat and electric power for the process; the gas stream at core exit is heated to 1850 F. Reactor operation is described and reactor innards are illustrated. A cost assessment for on-stream performance in the 1990's is optimistic.

  5. Comment on “Glacial cycles drive variations in the production of oceanic crust”

    NASA Astrophysics Data System (ADS)

    Goff, John A.

    2015-09-01

    Crowley et al. (Reports, 13 March 2015, p. 1237) propose that abyssal hill topography can be generated by variations in volcanism at mid-ocean ridges modulated by Milankovitch cycle-driven changes in sea level. Published values for abyssal hill characteristic widths versus spreading rate do not generally support this hypothesis. I argue that abyssal hills are primarily fault-generated rather than volcanically generated features.

  6. Comment on "Glacial cycles drive variations in the production of oceanic crust".

    PubMed

    Goff, John A

    2015-09-01

    Crowley et al. (Reports, 13 March 2015, p. 1237) propose that abyssal hill topography can be generated by variations in volcanism at mid-ocean ridges modulated by Milankovitch cycle-driven changes in sea level. Published values for abyssal hill characteristic widths versus spreading rate do not generally support this hypothesis. I argue that abyssal hills are primarily fault-generated rather than volcanically generated features.

  7. Successive reactivation of older structures under variable heat flow conditions evidenced by K-Ar fault gouge dating in Sierra de Ambato, northern Argentine broken foreland

    NASA Astrophysics Data System (ADS)

    Nóbile, Julieta C.; Collo, Gilda; Dávila, Federico M.; Martina, Federico; Wemmer, Klaus

    2015-12-01

    The Argentine broken foreland has been the subject of continuous research to determine the uplift and exhumation history of the region. High-elevation mountains are the result of N-S reverse faults that disrupted a W-E Miocene Andean foreland basin. In the Sierra de Ambato (northern Argentine broken foreland) the reverse faults offset Neogene sedimentary rocks (Aconquija Fm., ˜9 Ma) and affect the basement comprising Paleozoic metamorphic rocks that have been dated at ˜477-470 Ma. In order to establish a chronology of these faults affecting the previous continuous basin we date the formation age of clay minerals associated with fault gouge using the K-Ar dating technique. Clay mineral formation is a fundamental process in the evolution of faults under the brittle regime (<<300 °C). K-Ar ages (9 fractions from 3 samples collected along a transect in the Sierra de Ambato) vary from Late Devonian to Late Triassic (˜360-220 Ma). This age distribution can be explained by a long lasting brittle deformation history with a minimum age of ˜360 Ma and a last clay minerals forming event at ˜220 Ma. Moreover, given the progression of apparent ages decreasing from coarse to fine size fractions (˜360-311 Ma for 2-1 μm grain size fraction, ˜326-286 Ma for 1-0.2 μm and ˜291-219 Ma of <0.2 μm), we modeled discrete deformation events at ˜417 Ma (ending of the Famatinian cycle), ˜317-326 Ma (end of Gondwanic orogeny), and ˜194-279 Ma (Early Permian - Jurassic deformation). According to our data, the Neogene reactivation would not have affected the K-Ar system neither generated a significant clay minerals crystallization in the fault gouge, although an exhumation of more than 2 Km is recorded in this period from stratigraphic data.

  8. Similar Transition States Mediate the Q-cycle and Superoxide Production by the Cytochrome bc1 Complex

    SciTech Connect

    Forquer, Isaac P.; Covian, Raul; Bowman, Michael K.; Trumpower, Bernard; Kramer, David M.

    2006-12-15

    The cytochrome bc complexes found in mitochondria, chloroplasts and many bacteria catalyze a critical reaction in their respective electron transport chains. The quinol oxidase (Qo) site in this complex oxidizes a hydroquinone (quinol), reducing two one-electron carriers, a low-potential cytochrome b heme and a ''Rieske'' iron-sulfur cluster. The overall electron transfer reactions are coupled to transmembrane translocation of protons via a ''Q-cycle'' mechanism, which generates proton motive force for ATP synthesis. Since semiquinone intermediates of quinol oxidation are generally highly reactive, one of the key questions in this field is: how does the Qo site oxidize quinol without the production of deleterious side reactions including superoxide production? We attempt to test three possible general models to account for this behavior: (1) The Qo site semiquinone (or quinol:imidazolate complex) is unstable and thus occurs at a very low steady-state concentration, limiting O2 reduction; (2) the Qo site semiquinone is highly stabilized making it unreactive towards oxygen; and (3) the Qo site catalyzes a quantum mechanically-coupled two-electron/two proton transfer without a semiquinone intermediate. Enthalpies of activation were found to be almost identical between the uninhibited Q-cycle and superoxide production in the presence of Antimycin A in wild type. This behavior was also preserved in a series of mutants with altered driving forces for quinol oxidation. Overall, the data supports models where the rate-limiting step for both Q-cycle and superoxide production are essentially identical, consistent with model 1 but requiring modifications to models 2 and 3.

  9. Molecular identification, morphological characterization and new insights into the ecology of larval Pseudoterranova cattani in fishes from the Argentine coast with its differentiation from the Antarctic species, P. decipiens sp. E (Nematoda: Anisakidae).

    PubMed

    Timi, Juan T; Paoletti, Michela; Cimmaruta, Roberta; Lanfranchi, Ana L; Alarcos, Ana J; Garbin, Lucas; George-Nascimento, Mario; Rodríguez, Diego H; Giardino, Gisela V; Mattiucci, Simonetta

    2014-01-17

    Larvae of the genus Pseudoterranova constitute a risk for human health when ingested through raw or undercooked fish. They can provoke pseudoterranovosis in humans, a fish-borne zoonotic disease whose pathogenicity varies with the species involved, making their correct specific identification a necessary step in the knowledge of this zoonosis. Larvae of Pseudoterranova decipiens s.l. have been reported in several fish species from off the Argentine coasts; however, there are no studies dealing with their specific identification in this region. Here, a genetic identification and morphological characterization of larval Pseudoterranova spp. from three fish species sampled from Argentine waters and from Notothenia coriiceps from Antarctic waters was carried out. Larvae were sequenced for their genetic/molecular identification, including the mitochondrial cytochrome c oxidase subunit II (mtDNA cox2), the first (ITS-1) and the second (ITS-2) internal transcribed spacers of the nuclear ribosomal DNA, and compared with all species of the P. decipiens (sensu lato) species complex (sequences available in GenBank). Further, adults of Pseudoterranova spp. from the definitive host, the southern sea lion, Otaria flavescens, from Argentine and Chilean coasts were sequenced at the same genes. The sequences obtained at the ITS-1 and ITS-2 genes from all the larvae examined from fish of Argentine waters, as well as the adult worms, matched 100% the sequences for the species P. cattani. The sequences obtained at mtDNA cox2 gene for Antarctic larvae matched 99% those available in GenBank for the sibling P. decipiens sp. E. Both MP and BI phylogenetic trees strongly supported P. cattani and P. decipiens sp. E as two distinct phylogenetic lineages and depicted the species P. decipiens sp. E as sister taxon to the remaining taxa of the P. decipiens complex. Larval morphometry was similar between specimens of P. cattani from Argentina, but significantly different from those of P

  10. Life- cycle assessment in pesticide product development: methods and case study on two plant-growth regulators from different product generations.

    PubMed

    Geisler, Georg; Hellweg, Stefanie; Hofstetter, Thomas B; Hungerbuehler, Konrad

    2005-04-01

    Environmental assessments in pesticide product development are generally restricted to plant uptake and emissions of active ingredients. Life-cycle assessment (LCA) enables a more comprehensive evaluation by additionally assessing the impacts of pesticide production and application (e.g. tractor operations). The use of LCA in the product development of pesticides, in addition to the methods commonly applied, is therefore advisable. In this paper a procedure for conducting LCA in early phases of product development is proposed. In a case study, two plant-growth regulators from different product generations were compared regarding their application in intensive production of winter wheat. The results showed thatthe reduced emissions from active ingredients of the newer pesticide were compensated by higher impacts from the production process. The authors draw the conclusion that it is important to consider environmental objectives in the procurement of precursors, in addition to the classical goals of increasing the efficacy and reducing the nontarget effects of pesticides. Moreover, the case study showed that decisions based on uncertain results in early stages of product development may need to be revised in later stages, e.g. based on investigations of pesticides' effects on crop yield.

  11. Production of tartrates by cyanide-mediated dimerization of glyoxylate: a potential abiotic pathway to the citric acid cycle.

    PubMed

    Butch, Christopher; Cope, Elizabeth D; Pollet, Pamela; Gelbaum, Leslie; Krishnamurthy, Ramanarayanan; Liotta, Charles L

    2013-09-11

    An abiotic formation of meso- and DL-tartrates in 80% yield via the cyanide-catalyzed dimerization of glyoxylate under alkaline conditions is demonstrated. A detailed mechanism for this conversion is proposed, supported by NMR evidence and (13)C-labeled reactions. Simple dehydration of tartrates to oxaloacetate and an ensuing decarboxylation to form pyruvate are known processes that provide a ready feedstock for entry into the citric acid cycle. While glyoxylate and high hydroxide concentration are atypical in the prebiotic literature, there is evidence for natural, abiotic availability of each. It is proposed that this availability, coupled with the remarkable efficiency of tartrate production from glyoxylate, merits consideration of an alternative prebiotic pathway for providing constituents of the citric acid cycle.

  12. Production of Tartrates by Cyanide-Mediated Dimerization of Glyoxylate: A Potential Abiotic Pathway to the Citric Acid Cycle

    PubMed Central

    2013-01-01

    An abiotic formation of meso- and dl-tartrates in 80% yield via the cyanide-catalyzed dimerization of glyoxylate under alkaline conditions is demonstrated. A detailed mechanism for this conversion is proposed, supported by NMR evidence and 13C-labeled reactions. Simple dehydration of tartrates to oxaloacetate and an ensuing decarboxylation to form pyruvate are known processes that provide a ready feedstock for entry into the citric acid cycle. While glyoxylate and high hydroxide concentration are atypical in the prebiotic literature, there is evidence for natural, abiotic availability of each. It is proposed that this availability, coupled with the remarkable efficiency of tartrate production from glyoxylate, merits consideration of an alternative prebiotic pathway for providing constituents of the citric acid cycle. PMID:23914725

  13. Effect of seasonal flooding cycle on litterfall production in alluvial rainforest on the middle Xingu River (Amazon basin, Brazil).

    PubMed

    Camargo, M; Giarrizzo, T; Jesus, A J S

    2015-08-01

    The assumption for this study was that litterfall in floodplain environments of the middle Xingu river follows a pattern of seasonal variation. According to this view, litterfall production (total and fractions) was estimated in four alluvial rainforest sites on the middle Xingu River over an annual cycle, and examined the effect of seasonal flooding cycle. The sites included two marginal flooded forests of insular lakes (Ilha Grande and Pimentel) and two flooded forests on the banks of the Xingu itself (Boa Esperança and Arroz Cru). Total litterfall correlated with rainfall and river levels, but whereas the leaf and fruit fractions followed this general pattern, the flower fraction presented an inverse pattern, peaking in the dry season. The litterfall patterns recorded in the present study were consistent with those recorded at other Amazonian sites, and in some other tropical ecosystems.

  14. Effect of seasonal flooding cycle on litterfall production in alluvial rainforest on the middle Xingu River (Amazon basin, Brazil).

    PubMed

    Camargo, M; Giarrizzo, T; Jesus, A J S

    2015-08-01

    The assumption for this study was that litterfall in floodplain environments of the middle Xingu river follows a pattern of seasonal variation. According to this view, litterfall production (total and fractions) was estimated in four alluvial rainforest sites on the middle Xingu River over an annual cycle, and examined the effect of seasonal flooding cycle. The sites included two marginal flooded forests of insular lakes (Ilha Grande and Pimentel) and two flooded forests on the banks of the Xingu itself (Boa Esperança and Arroz Cru). Total litterfall correlated with rainfall and river levels, but whereas the leaf and fruit fractions followed this general pattern, the flower fraction presented an inverse pattern, peaking in the dry season. The litterfall patterns recorded in the present study were consistent with those recorded at other Amazonian sites, and in some other tropical ecosystems. PMID:26691098

  15. Policy implications of allocation methods in the life cycle analysis of integrated corn and corn stover ethanol production

    DOE PAGES

    Canter, Christina E.; Dunn, Jennifer B.; Han, Jeongwoo; Wang, Zhichao; Wang, Michael

    2015-08-18

    Here, a biorefinery may produce multiple fuels from more than one feedstock. The ability of these fuels to qualify as one of the four types of biofuels under the US Renewable Fuel Standard and to achieve a low carbon intensity score under California’s Low Carbon Fuel Standard can be strongly influenced by the approach taken to their life cycle analysis (LCA). For example, in facilities that may co-produce corn grain and corn stover ethanol, the ethanol production processes can share the combined heat and power (CHP) that is produced from the lignin and liquid residues from stover ethanol production. Wemore » examine different LCA approaches to corn grain and stover ethanol production considering different approaches to CHP treatment. In the baseline scenario, CHP meets the energy demands of stover ethanol production first, with additional heat and electricity generated sent to grain ethanol production. The resulting greenhouse gas (GHG) emissions for grain and stover ethanol are 57 and 25 g-CO2eq/MJ, respectively, corresponding to a 40 and 74% reduction compared to the GHG emissions of gasoline. We illustrate that emissions depend on allocation of burdens of CHP production and corn farming, along with the facility capacities. Co-product handling techniques can strongly influence LCA results and should therefore be transparently documented.« less

  16. Policy implications of allocation methods in the life cycle analysis of integrated corn and corn stover ethanol production

    SciTech Connect

    Canter, Christina E.; Dunn, Jennifer B.; Han, Jeongwoo; Wang, Zhichao; Wang, Michael

    2015-08-18

    Here, a biorefinery may produce multiple fuels from more than one feedstock. The ability of these fuels to qualify as one of the four types of biofuels under the US Renewable Fuel Standard and to achieve a low carbon intensity score under California’s Low Carbon Fuel Standard can be strongly influenced by the approach taken to their life cycle analysis (LCA). For example, in facilities that may co-produce corn grain and corn stover ethanol, the ethanol production processes can share the combined heat and power (CHP) that is produced from the lignin and liquid residues from stover ethanol production. We examine different LCA approaches to corn grain and stover ethanol production considering different approaches to CHP treatment. In the baseline scenario, CHP meets the energy demands of stover ethanol production first, with additional heat and electricity generated sent to grain ethanol production. The resulting greenhouse gas (GHG) emissions for grain and stover ethanol are 57 and 25 g-CO2eq/MJ, respectively, corresponding to a 40 and 74% reduction compared to the GHG emissions of gasoline. We illustrate that emissions depend on allocation of burdens of CHP production and corn farming, along with the facility capacities. Co-product handling techniques can strongly influence LCA results and should therefore be transparently documented.

  17. Advances in life cycle assessment and emergy evaluation with case studies in gold mining and pineapple production

    NASA Astrophysics Data System (ADS)

    Ingwersen, Wesley W.

    Life cycle assessment (LCA) is an internationally standardized framework for assessing the environmental impacts of products that is rapidly evolving to improve understanding and quantification of how complex product systems depend upon and affect the environment. This dissertation contributes to that evolution through the development of new methods for measuring impacts, estimating the uncertainty of impacts, and measuring ranges of environmental performance, with a focus on product systems in non-OECD countries that have not been well characterized. The integration of a measure of total energy use, emergy, is demonstrated in an LCA of gold from the Yanacocha mine in Peru in the second chapter. A model for estimating the accuracy of emergy results is proposed in the following chapter. The fourth chapter presents a template for LCA-based quantification of the range of environmental performance for tropical agricultural products using the example of fresh pineapple production for export in Costa Rica that can be used to create product labels with environmental information. The final chapter synthesizes how each methodological contribution will together improve the science of measuring product environmental performance.

  18. Life cycle assessment of biodiesel production from algal bio-crude oils extracted under subcritical water conditions.

    PubMed

    Ponnusamy, Sundaravadivelnathan; Reddy, Harvind Kumar; Muppaneni, Tapaswy; Downes, Cara Meghan; Deng, Shuguang

    2014-10-01

    A life cycle assessment study is performed for the energy requirements and greenhouse gas emissions in an algal biodiesel production system. Subcritical water (SCW) extraction was applied for extracting bio-crude oil from algae, and conventional transesterification method was used for converting the algal oil to biodiesel. 58MJ of energy is required to produce 1kg of biodiesel without any co-products management, of which 36% was spent on cultivation and 56% on lipid extraction. SCW extraction with thermal energy recovery reduces the energy consumption by 3-5 folds when compared to the traditional solvent extraction. It is estimated that 1kg of algal biodiesel fixes about 0.6kg of CO2. An optimized case considering the energy credits from co-products could further reduce the total energy demand. The energy demand for producing 1kg of biodiesel in the optimized case is 28.23MJ.

  19. The chemical state of fission products in oxide fuels at different stages of the nuclear fuel cycle

    SciTech Connect

    Kleykamp, H.

    1988-03-01

    A survey of work at the Kernforschungszentrum Karlsruhe is presented on the chemical state of selected fission products that are relevant in the fuel cycle of light water reactor (LWR) and fast breeder reactor fuels. The influence of fuel type and irradiation progress on the composition of the Mo-Tc-Ru-Rh-Pd fission product alloys precipitated in the oxide matrix is examined using the respective multicomponent phase diagrams. The kinetics of dissolution of these phases in nitric acid at the reprocessing stage is discussed. Composition and structure of the residues, and the reprecipitation phenomena from highly active waste (HAW), are elucidated. A second metamorphosis of the fission products is recognized during the vitrification process. The formation of Ru(Rh) oxide and Pd(Rh, U, Te) alloys in simulated vitrified HAW concentrate and in HAW concentrate from the reprocessing of irradiated LWR fuels in interpreted on the basis of heterogeneous equilibria.

  20. Life cycle inventory of the production of rare earths and the subsequent production of NdFeB rare earth permanent magnets.

    PubMed

    Sprecher, Benjamin; Xiao, Yanping; Walton, Allan; Speight, John; Harris, Rex; Kleijn, Rene; Visser, Geert; Kramer, Gert Jan

    2014-04-01

    Neodymium is one of the more critical rare earth elements with respect to current availability and is most often used in high performance magnets. In this paper, we compare the virgin production route of these magnets with two hypothetical recycling processes in terms of environmental impact. The first recycling process looks at manual dismantling of computer hard disk drives (HDDs) combined with a novel hydrogen based recycling process. The second process assumes HDDs are shredded. Our life cycle assessment is based both on up to date literature and on our own experimental data. Because the production process of neodymium oxide is generic to all rare earths, we also report the life cycle inventory data for the production of rare earth oxides separately. We conclude that recycling of neodymium, especially via manual dismantling, is preferable to primary production, with some environmental indicators showing an order of magnitude improvement. The choice of recycling technology is also important with respect to resource recovery. While manual disassembly allows in principle for all magnetic material to be recovered, shredding leads to very low recovery rates (<10%).

  1. 40 CFR 721.9300 - Reaction products of substituted hydroxy-alkanes and polyalkylpolyisocyanatocarbomono- cycle.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Reaction products of substituted... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9300 Reaction products of... significant new uses subject to reporting. (1) The chemical substance identified generically as...

  2. 40 CFR 721.9300 - Reaction products of substituted hydroxy-alkanes and polyalkylpolyisocyanatocarbomono- cycle.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Reaction products of substituted... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9300 Reaction products of... significant new uses subject to reporting. (1) The chemical substance identified generically as...

  3. 40 CFR 721.9300 - Reaction products of substituted hydroxy-alkanes and polyalkylpolyisocyanatocarbomono- cycle.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Reaction products of substituted... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9300 Reaction products of... significant new uses subject to reporting. (1) The chemical substance identified generically as...

  4. 40 CFR 721.9300 - Reaction products of substituted hydroxy-alkanes and polyalkylpolyisocyanatocarbomono- cycle.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reaction products of substituted... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9300 Reaction products of... significant new uses subject to reporting. (1) The chemical substance identified generically as...

  5. 40 CFR 721.9300 - Reaction products of substituted hydroxy-alkanes and polyalkylpolyisocyanatocarbomono- cycle.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Reaction products of substituted... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9300 Reaction products of... significant new uses subject to reporting. (1) The chemical substance identified generically as...

  6. Mitigation opportunities for life cycle greenhouse gas emissions during feedstock production across heterogeneous landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feedstock production can contribute greater than or equal to 50% of the lifecycle global warming intensity (GWI) of a biofuel. Variability exists within and among high-leverage components of the biomass production phase. GWI variability within feedstocks has gone unrecognized by regulatory agencies....

  7. Instantaneous quantification of skeletal muscle activation, power production, and fatigue during cycle ergometry.

    PubMed

    Coelho, A C; Cannon, D T; Cao, R; Porszasz, J; Casaburi, R; Knorst, M M; Rossiter, H B

    2015-03-01

    A rapid switch from hyperbolic to isokinetic cycling allows the velocity-specific decline in maximal power to be measured, i.e., fatigue. We reasoned that, should the baseline relationship between isokinetic power (Piso) and electromyography (EMG) be reproducible, then contributions to fatigue may be isolated from 1) the decline in muscle activation (muscle activation fatigue); and 2) the decline in Piso at a given activation (muscle fatigue). We hypothesized that the EMG-Piso relationship is linear, velocity dependent, and reliable for instantaneous fatigue assessment at intolerance during and following whole body exercise. Healthy participants (n = 13) completed short (5 s) variable-effort isokinetic bouts at 50, 70, and 100 rpm to characterize baseline EMG-Piso. Repeated ramp incremental exercise tests were terminated with maximal isokinetic cycling (5 s) at 70 rpm. Individual baseline EMG-Piso relationships were linear (r(2) = 0.95 ± 0.04) and velocity dependent (analysis of covariance). Piso at intolerance (two legs, 335 ± 88 W) was ∼45% less than baseline [630 ± 156 W, confidence interval of the difference (CIDifference) 211, 380 W, P < 0.05]. Following intolerance, Piso recovered rapidly (F = 44.1; P < 0.05; η(2) = 0.79): power was reduced (P < 0.05) vs. baseline only at 0-min (CIDifference 80, 201 W) and 1-min recovery (CIDifference 13, 80 W). Activation fatigue and muscle fatigue (one leg) were 97 ± 55 and 60 ± 50 W, respectively. Mean bias ± limits of agreement for reproducibility were as follows: baseline Piso 1 ± 30 W; Piso at 0-min recovery 3 ± 35 W; and EMG at Piso 3 ± 14%. EMG power is linear, velocity dependent, and reproducible. Deviation from this relationship at the limit of tolerance can quantify the "activation" and "muscle" related components of fatigue during cycling.

  8. Improved Environmental Life Cycle Assessment of Crop Production at the Catchment Scale via a Process-Based Nitrogen Simulation Model.

    PubMed

    Liao, Wenjie; van der Werf, Hayo M G; Salmon-Monviola, Jordy

    2015-09-15

    One of the major challenges in environmental life cycle assessment (LCA) of crop production is the nonlinearity between nitrogen (N) fertilizer inputs and on-site N emissions resulting from complex biogeochemical processes. A few studies have addressed this nonlinearity by combining process-based N simulation models with LCA, but none accounted for nitrate (NO3(-)) flows across fields. In this study, we present a new method, TNT2-LCA, that couples the topography-based simulation of nitrogen transfer and transformation (TNT2) model with LCA, and compare the new method with a current LCA method based on a French life cycle inventory database. Application of the two methods to a case study of crop production in a catchment in France showed that, compared to the current method, TNT2-LCA allows delineation of more appropriate temporal limits when developing data for on-site N emissions associated with specific crops in this catchment. It also improves estimates of NO3(-) emissions by better consideration of agricultural practices, soil-climatic conditions, and spatial interactions of NO3(-) flows across fields, and by providing predicted crop yield. The new method presented in this study provides improved LCA of crop production at the catchment scale.

  9. Stomatal controls on vegetation productivity and water cycling across the African continent in a warmer and CO2 enriched climate

    NASA Astrophysics Data System (ADS)

    Sato, H.; Kumagai, T.; Takahashi, A.; Katul, G. G.

    2014-12-01

    General Circulation Models (GCMs) forecast higher vapor pressure deficit (VPD) but unchanged relative humidity (RH) in future climates. A recent literature survey revealed some 50% of Earth System (ESMs) and Land Surface (LSMs) Models embedded within GCMs employ RH as an atmospheric aridity index when describing stomatal conductance (gs) while the remaining 50% employ VPD. Propagating the consequences of using RH or VPD in gs models on water cycling and vegetation productivity in future climates in one of the most vulnerable continents, the African continent, remains to be explored. Using process-based global dynamic vegetation model runs, changes in the hydrological cycle and concomitant vegetation productivity for a 21st century projected climate are conducted by altering only gs responses to VPD or RH while maintaining all other formulations unaltered. In the simulations under warming trend of the 21st century, both stomata functions of VPD and RH result in nearly identical changes in the geographic pattern of Gross Primary Production (GPP). However, continental total of GPP becomes bit larger for the VPD function than for the RH function. Transpiration rates becomes lower resulting in water-use-efficiency becoming higher by some 13% for the VPD function when compared to its RH counterpart.

  10. Uncertainty in the Life Cycle Greenhouse Gas Emissions from U.S. Production of Three Biobased Polymer Families.

    PubMed

    Posen, I Daniel; Jaramillo, Paulina; Griffin, W Michael

    2016-03-15

    Interest in biobased products has been motivated, in part, by the claim that these products have lower life cycle greenhouse gas (GHG) emissions than their fossil counterparts. This study investigates GHG emissions from U.S. production of three important biobased polymer families: polylactic acid (PLA), polyhydroxybutyrate (PHB) and bioethylene-based plastics. The model incorporates uncertainty into the life cycle emission estimates using Monte Carlo simulation. Results present a range of scenarios for feedstock choice (corn or switchgrass), treatment of coproducts, data sources, end of life assumptions, and displaced fossil polymer. Switchgrass pathways generally have lower emissions than corn pathways, and can even generate negative cradle-to-gate emissions if unfermented residues are used to coproduce energy. PHB (from either feedstock) is unlikely to have lower emissions than fossil polymers once end of life emissions are included. PLA generally has the lowest emissions when compared to high emission fossil polymers, such as polystyrene (mean GHG savings up to 1.4 kg CO2e/kg corn PLA and 2.9 kg CO2e/kg switchgrass PLA). In contrast, bioethylene is likely to achieve the greater emission reduction for ethylene intensive polymers, like polyethylene (mean GHG savings up to 0.60 kg CO2e/kg corn polyethylene and 3.4 kg CO2e/kg switchgrass polyethylene).

  11. Environmental Life Cycle Implications of Fuel Oxygenate Production from California Biomass

    SciTech Connect

    B.E. Glazebrook; D.C. Simeroth (California Air Resources Board; K.C. Nehoda (California Department of Forestry.

    1999-05-20

    Historically, more than 90% of the excess agricultural residue produced in California (approximately 10 million dry metric tons per year) has been disposed through open-field burning. Concerns about air quality have prompted federal, state, and local air quality agencies to tighten regulations related to this burning and to look at disposal alternatives. One use of this biomass is as an oxygenated fuel. This report focuses on quantifying and comparing the comprehensive environmental flows over the life cycles of two disposal scenarios: (1) burning the biomass, plus producing and using MTBE; and (2) converting and using ETBE.

  12. Life Cycle Assessment of Greenhouse Gas Emissions from Dairy Production in a Central New York State Watershed

    NASA Astrophysics Data System (ADS)

    Johnson, M. S.

    2009-12-01

    Cumulative greenhouse gas emissions related to dairy production in the Fall Creek watershed of central New York State were calculated using a life-cycle approach for the period 1975-2001. Expressed as CO2 equivalents (CO2e), emissions include CO2, CH4 and N2O related to fertilizer manufacture and transport, bovine metabolism, volatilization and leaching losses from applied fertilizer, nitrogen dynamics in crop residues, among a myriad of sources. During the 1975-2001 period, dairy N production in the study area increased by over 20%, although crop N production in the watershed declined by 33%. This change was driven by consolidation within the dairy industry that also led to a six-fold increase in N in feed imports into the watershed during the same period. Cumulative GHG emissions related to dairy production in Fall Creek rose by about 20% over 1975-2001 to about 14,000 tons CO2e per year for the 326 km2 watershed by 2001. In 1975, about 90% of CO2e emissions related to dairy production in the Fall Creek watershed were emitted within the watershed. However, by 2001 over 50% of emissions were generated outside of the watershed, primarily as N2O emissions related to fertilizer used in the production of feed subsequently imported into Fall Creek watershed.

  13. Experimental Study of Magnesium Production with Laser for Clean Energy Cycle

    NASA Astrophysics Data System (ADS)

    Sato, Y.; Yabe, T.; Sakurai, Y.; Mohamed, M. S.; Uchida, S.; Baasandash, C.; Ohkubo, T.; Mori, Y.; Sato, H.

    2008-04-01

    A new scheme of generating power called magnesium injection cycle [MAGIC] engine was developed. Magnesium [Mg] and water are put into the chamber and ignited at 500 degree Celsius. Mg reaction with water produces hydrogen [H2] gas. The hydrogen blows out and reacts with oxygen [O2] gas to generate H2O and energy at the exit nozzle. These reactions occur simultaneously and generate thrust. In order to reproduce Mg, the residual MgO is irradiated by focused cw CO2 laser (1000 W) at 20 Pa. Then, high temperature (over 4000 degree Celsius) is exerted in tiny spot thus MgO reduction in equilibrium is achievable. Spectroscopic analysis was conducted on the Mg/MgO vapor under atmospheric condition. The Mg line at 518 nm, MgO line at 500 nm and O+ line were confirmed. This proves that the MgO is dissociated by laser irradiation These experiments confirm that the scheme can be used for magnesium energy cycle system with practical efficiency and large throughput.

  14. Heck products of parthenolide and melampomagnolide-B as anticancer modulators that modify cell cycle progression

    PubMed Central

    Penthala, Narsimha R.; Bommagani, Shobanbabu; Janganati, Venumadhav; MacNicol, Kenzie B.; Cragle, Chad E.; Madadi, Nikhil R.; Hardy, Linda L.; MacNicol, Angus M.; Crooks, Peter A.

    2014-01-01

    (E)-13-(Aryl/heteroaryl)parthenolides (5a–i and 6a–i) were synthesized and evaluated for their ability to modify cell cycle progression during progesterone-stimulated Xenopus oocyte maturation and screened for their anticancer activity against a panel of 60 human cancer cell lines. (E)-13-(4-aminophenyl) parthenolide (5b) caused a significant inhibition of progesterone-stimulated oocyte maturation, and was determined to function downstream of MAP kinase signaling, but upstream of the activation of the universal G2/M regulator, M-phase promoting factor (MPF, cyclin B/Cyclin-dependent kinase (CDK). The compound (E)-13-(2-bromo-phenyl)parthenolide (5c) activates oocyte maturation independently of progesterone stimulation. Compounds 5b and 5c displayed modest growth inhibition on select cancer cell lines at 10 micromolar dose when tested on the panel of 60 cancer cell lines. By contrast, compounds (5f and 7) did not modulate oocyte maturation but did exhibit micromolar level growth inhibition against most of the human cancer cell lines over a range of doses. Together, our findings indicate that screening of compounds in the oocyte maturation assay may identify additional effective cell cycle regulatory compounds that do not necessarily exert overt cytotoxicity as assessed in traditional drug screening assays. PMID:25117652

  15. Heck products of parthenolide and melampomagnolide-B as anticancer modulators that modify cell cycle progression.

    PubMed

    Penthala, Narsimha R; Bommagani, Shobanbabu; Janganati, Venumadhav; MacNicol, Kenzie B; Cragle, Chad E; Madadi, Nikhil R; Hardy, Linda L; MacNicol, Angus M; Crooks, Peter A

    2014-10-01

    (E)-13-(Aryl/heteroaryl)parthenolides (5a-i and 6a-i) were synthesized and evaluated for their ability to modify cell cycle progression during progesterone-stimulated Xenopus oocyte maturation and screened for their anticancer activity against a panel of 60 human cancer cell lines. (E)-13-(4-aminophenyl) parthenolide (5b) caused a significant inhibition of progesterone-stimulated oocyte maturation, and was determined to function downstream of MAP kinase signaling, but upstream of the activation of the universal G2/M regulator, M-phase promoting factor (MPF), cyclin B/Cyclin-dependent kinase (CDK). The compound (E)-13-(2-bromo-phenyl)parthenolide (5c) activates oocyte maturation independently of progesterone stimulation. Compounds 5b and 5c displayed modest growth inhibition on select cancer cell lines at 10 μM dose when tested on the panel of 60 cancer cell lines. By contrast, compounds (5f and 7) did not modulate oocyte maturation but did exhibit micromolar level growth inhibition against most of the human cancer cell lines over a range of doses. Together, our findings indicate that screening of compounds in the oocyte maturation assay may identify additional effective cell cycle regulatory compounds that do not necessarily exert overt cytotoxicity as assessed in traditional drug screening assays.

  16. The nuclear and adherent junction complex component protein ubinuclein negatively regulates the productive cycle of Epstein-Barr virus in epithelial cells.

    PubMed

    Gruffat, Henri; Lupo, Julien; Morand, Patrice; Boyer, Véronique; Manet, Evelyne

    2011-01-01

    The Epstein-Barr Virus (EBV) productive cycle is initiated by the expression of the viral trans-activator EB1 (also called Zebra, Zta, or BZLF1), which belongs to the basic leucine zipper transcription factor family. We have previously identified the cellular NACos (nuclear and adherent junction complex components) protein ubinuclein (Ubn-1) as a partner for EB1, but the function of this complex has never been studied. Here, we have evaluated the consequences of this interaction on the EBV productive cycle and find that Ubn-1 overexpression represses the EBV productive cycle whereas Ubn-1 downregulation by short hairpin RNA (shRNA) increases virus production. By a chromatin immunoprecipitation (ChIP) assay, we show that Ubn-1 blocks EB1-DNA interaction. We also show that in epithelial cells, relocalization and sequestration of Ubn-1 to the tight junctions of nondividing cells allow increased activation of the productive cycle. We propose a model in which Ubn-1 is a modulator of the EBV productive cycle: in proliferating epithelial cells, Ubn-1 is nuclear and inhibits activation of the productive cycle, whereas in differentiated cells, Ubn-1 is sequestrated to tight junctions, thereby allowing EB1 to fully function in the nucleus.

  17. The Nuclear and Adherent Junction Complex Component Protein Ubinuclein Negatively Regulates the Productive Cycle of Epstein-Barr Virus in Epithelial Cells▿

    PubMed Central

    Gruffat, Henri; Lupo, Julien; Morand, Patrice; Boyer, Véronique; Manet, Evelyne

    2011-01-01

    The Epstein-Barr Virus (EBV) productive cycle is initiated by the expression of the viral trans-activator EB1 (also called Zebra, Zta, or BZLF1), which belongs to the basic leucine zipper transcription factor family. We have previously identified the cellular NACos (nuclear and adherent junction complex components) protein ubinuclein (Ubn-1) as a partner for EB1, but the function of this complex has never been studied. Here, we have evaluated the consequences of this interaction on the EBV productive cycle and find that Ubn-1 overexpression represses the EBV productive cycle whereas Ubn-1 downregulation by short hairpin RNA (shRNA) increases virus production. By a chromatin immunoprecipitation (ChIP) assay, we show that Ubn-1 blocks EB1-DNA interaction. We also show that in epithelial cells, relocalization and sequestration of Ubn-1 to the tight junctions of nondividing cells allow increased activation of the productive cycle. We propose a model in which Ubn-1 is a modulator of the EBV productive cycle: in proliferating epithelial cells, Ubn-1 is nuclear and inhibits activation of the productive cycle, whereas in differentiated cells, Ubn-1 is sequestrated to tight junctions, thereby allowing EB1 to fully function in the nucleus. PMID:21084479

  18. ZOOPLANKTON LIFE CYCLES: DIRECT DOCUMENTATION OF PELAGIC BIRTHS AND DEATHS RELATIVE TO DIAPAUSING EGG PRODUCTION

    EPA Science Inventory

    Full-season demographics (pelagic births and deaths, diapause egg production) provide valuable insights into species persistence and dispersal success. The spiny cladoceran (Bythotrephes) possesses morphological adaptations (spines and thick-walled diapause eggs) that lessen impa...

  19. Bioenergy co-products derived from microalgae biomass via thermochemical conversion--life cycle energy balances and CO2 emissions.

    PubMed

    Khoo, H H; Koh, C Y; Shaik, M S; Sharratt, P N

    2013-09-01

    An investigation of the potential to efficiently convert lipid-depleted residual microalgae biomass using thermochemical (gasification at 850 °C, pyrolysis at 550 °C, and torrefaction at 300 °C) processes to produce bioenergy derivatives was made. Energy indicators are established to account for the amount of energy inputs that have to be supplied to the system in order to gain 1 MJ of bio-energy output. The paper seeks to address the difference between net energy input-output balances based on a life cycle approach, from "cradle-to-bioenergy co-products", vs. thermochemical processes alone. The experimental results showed the lowest results of Net Energy Balances (NEB) to be 0.57 MJ/MJ bio-oil via pyrolysis, and highest, 6.48 MJ/MJ for gas derived via torrefaction. With the complete life cycle process chain factored in, the energy balances of NEBLCA increased to 1.67 MJ/MJ (bio-oil) and 7.01 MJ/MJ (gas). Energy efficiencies and the life cycle CO2 emissions were also calculated.

  20. Bridging the gap between life cycle inventory and impact assessment for toxicological assessments of pesticides used in crop production.

    PubMed

    van Zelm, Rosalie; Larrey-Lassalle, Pyrène; Roux, Philippe

    2014-04-01

    In Life Cycle Assessment (LCA), the Life Cycle Inventory (LCI) provides emission data to the various environmental compartments and Life Cycle Impact Assessment (LCIA) determines the final distribution, fate and effects. Due to the overlap between the Technosphere (anthropogenic system) and Ecosphere (environment) in agricultural case studies, it is, however, complicated to establish what LCI needs to capture and where LCIA takes over. This paper aims to provide guidance and improvements of LCI/LCIA boundary definitions, in the dimensions of space and time. For this, a literature review was conducted to provide a clear overview of available methods and models for both LCI and LCIA regarding toxicological assessments of pesticides used in crop production. Guidelines are provided to overcome the gaps between LCI and LCIA modeling, and prevent the overlaps in their respective operational spheres. The proposed framework provides a starting point for LCA practitioners to gather the right data and use the proper models to include all relevant emission and exposure routes where possible. It is also able to predict a clear distinction between efficient and inefficient management practices (e.g. using different application rates, washing and rinsing management, etc.). By applying this framework for toxicological assessments of pesticides, LCI and LCIA can be directly linked, removing any overlaps or gaps in between the two distinct LCA steps.

  1. Bioenergy co-products derived from microalgae biomass via thermochemical conversion--life cycle energy balances and CO2 emissions.

    PubMed

    Khoo, H H; Koh, C Y; Shaik, M S; Sharratt, P N

    2013-09-01

    An investigation of the potential to efficiently convert lipid-depleted residual microalgae biomass using thermochemical (gasification at 850 °C, pyrolysis at 550 °C, and torrefaction at 300 °C) processes to produce bioenergy derivatives was made. Energy indicators are established to account for the amount of energy inputs that have to be supplied to the system in order to gain 1 MJ of bio-energy output. The paper seeks to address the difference between net energy input-output balances based on a life cycle approach, from "cradle-to-bioenergy co-products", vs. thermochemical processes alone. The experimental results showed the lowest results of Net Energy Balances (NEB) to be 0.57 MJ/MJ bio-oil via pyrolysis, and highest, 6.48 MJ/MJ for gas derived via torrefaction. With the complete life cycle process chain factored in, the energy balances of NEBLCA increased to 1.67 MJ/MJ (bio-oil) and 7.01 MJ/MJ (gas). Energy efficiencies and the life cycle CO2 emissions were also calculated. PMID:23810951

  2. Energy balances in the production and end use of alcohols derived from biomass. A fuels-specific comparative analysis of alternate ethanol production cycles

    SciTech Connect

    Not Available

    1980-10-01

    Considerable public interest and debate have been focused on the so-called energy balance issue involved in the conversion of biomass materials into ethanol for fuel use. This report addresses questions of net gains in premium fuels that can be derived from the production and use of ethanol from biomass, and shows that for the US alcohol fuel program, energy balance need not be a concern. Three categories of fuel gain are discussed in the report: (1) Net petroleum gain; (2) Net premium fuel gain (petroleum and natural gas); and (3) Net energy gain (for all fuels). In this study the investment of energy (in the form of premium fuels) in alcohol production includes all investment from cultivating, harvesting, or gathering the feedstock and raw materials, through conversion of the feedstock to alcohol, to the delivery to the end-user. To determine the fuel gains in ethanol production, six cases, encompassing three feedstocks, five process fuels, and three process variations, have been examined. For each case, two end-uses (automotive fuel use and replacement of petrochemical feedstocks) were scrutinized. The end-uses were further divided into three variations in fuel economy and two different routes for production of ethanol from petrochemicals. Energy requirements calculated for the six process cycles accounted for fuels used directly and indirectly in all stages of alcohol production, from agriculture through distribution of product to the end-user. Energy credits were computed for byproducts according to the most appropriate current use.

  3. Menu Cycles.

    ERIC Educational Resources Information Center

    Clayton, Alfred; Almony, John

    The curriculum guide for commercial foods instruction is designed to aid the teacher in communicating the importance of menu cycles in commercial food production. It also provides information about the necessary steps in getting food from the raw form to the finished product, and then to the consumer. In addition to providing information on how to…

  4. Solar Thermochemical Fuels Production: Solar Fuels via Partial Redox Cycles with Heat Recovery

    SciTech Connect

    2011-12-19

    HEATS Project: The University of Minnesota is developing a solar thermochemical reactor that will efficiently produce fuel from sunlight, using solar energy to produce heat to break chemical bonds. The University of Minnesota is envisioning producing the fuel by using partial redox cycles and ceria-based reactive materials. The team will achieve unprecedented solar-to-fuel conversion efficiencies of more than 10% (where current state-of-the-art efficiency is 1%) by combined efforts and innovations in material development, and reactor design with effective heat recovery mechanisms and demonstration. This new technology will allow for the effective use of vast domestic solar resources to produce precursors to synthetic fuels that could replace gasoline.

  5. Life cycle risks for human health: a comparison of petroleum versus bio-based production of five bulk organic chemicals.

    PubMed

    Roes, Alexander L; Patel, Martin K

    2007-10-01

    This article describes the development and application of a generic approach to the comparative assessment of risks related to the production of organic chemicals by petrochemical processes versus white biotechnology. White biotechnology, also referred to as industrial biotechnology, typically uses bio-based feedstocks instead of the fossil raw materials used in the petrochemical sector. The purpose of this study was to investigate whether the production of chemicals by means of white biotechnology has lower conventional risks than their production by petrochemical processes. Conventional risks are the risks of well-established processes, and not those related to genetically modified microorganisms and plants. Our approach combines classical risk assessment methods (largely based on toxicology), as developed by the life cycle assessment (LCA) community, with statistics on technological disasters, accidents, and work-related illnesses. Moreover, it covers the total process chain for both petrochemical and bio-based products from cradle to grave. The approach was applied to five products: the plastics polytrimethylene terephthalate (PTT), polyhydroxyalkanoates (PHA), polyethylene terephthalate (PET), polyethylene (PE), and ethanol. Our results show that the conventional risks related to the white biotechnology products studied are lower than those of the petrochemical products. However, considering the uncertainties with respect to the ranges of input data, the (incomplete) coverage of emissions by the environmental priority strategies (EPS) 2000 method, and the uncertainties of the assumptions made in this study (i.e., large to very large), the differences in results between bio-based and petrochemical products fall into the uncertainty range. Because of this, future research is necessary to decrease the uncertainties before we can conclude that the conventional risks of biotechnologically produced chemicals are lower than those of fossil-fuel-derived chemicals.

  6. Life cycle assessment of innovative technology for energy production from automotive shredder residue.

    PubMed

    Rinaldi, Caterina; Masoni, Paolo; Salvati, Fabio; Tolve, Pietro

    2015-07-01

    Automotive Shredder Residue (ASR) is a problematic waste material remaining after shredding and recovery processes of end-of-life vehicles (ELVs). Its heterogeneous grain size and composition make difficult its recovery or disposal. Although ASR accounts for approximately 20% to 25% of the weight of an ELV, the European Union (EU)'s ELV Directive (2000/53/EC) requires that by 2015 a minimum 95% of the weight of an ELV must be reused or recovered, including a 10% weight energy recovery. The quantity of ASR is relevant: Approximately 2.4 million tons are generated in the EU each year and most of it is sent to landfills. This article describes a life cycle model of the "TEKNE-Fluff" process designed to make beneficial use of ASR that is based on the results of an experimental pilot plant for pyro-gasification, combustion, cogeneration, and emissions treatment of ASR. The goal of the research was the application of life cycle assessment (LCA) methodology to identify the environmental hot spots of the "TEKNE system" and use scenario analysis to check solutions to improve its environmental profile, supporting the design and industrialization process. The LCA was conducted based on data modeled from the experimental campaign. Moreover, different scenarios on shares of electricity and thermal energy produced by the cogeneration system and alternative treatment processes for the waste produced by the technology were compared. Despite the limitation of the research (results based on scaling up experimental data by modeling), impact assessment results are promising and sufficiently robust, as shown by Monte Carlo analysis. The TEKNE technology may become an interesting solution for the problem of ASR management: Besides representing an alternative to landfill disposal, the energy produced could avoid significant impacts on fossil resources depletion (a plant of 40,000 tons/y capacity could produce ∼ 147,000 GJ/yr, covering the annual need of ∼ 13,500 households).

  7. Life cycle assessment of innovative technology for energy production from automotive shredder residue.

    PubMed

    Rinaldi, Caterina; Masoni, Paolo; Salvati, Fabio; Tolve, Pietro

    2015-07-01

    Automotive Shredder Residue (ASR) is a problematic waste material remaining after shredding and recovery processes of end-of-life vehicles (ELVs). Its heterogeneous grain size and composition make difficult its recovery or disposal. Although ASR accounts for approximately 20% to 25% of the weight of an ELV, the European Union (EU)'s ELV Directive (2000/53/EC) requires that by 2015 a minimum 95% of the weight of an ELV must be reused or recovered, including a 10% weight energy recovery. The quantity of ASR is relevant: Approximately 2.4 million tons are generated in the EU each year and most of it is sent to landfills. This article describes a life cycle model of the "TEKNE-Fluff" process designed to make beneficial use of ASR that is based on the results of an experimental pilot plant for pyro-gasification, combustion, cogeneration, and emissions treatment of ASR. The goal of the research was the application of life cycle assessment (LCA) methodology to identify the environmental hot spots of the "TEKNE system" and use scenario analysis to check solutions to improve its environmental profile, supporting the design and industrialization process. The LCA was conducted based on data modeled from the experimental campaign. Moreover, different scenarios on shares of electricity and thermal energy produced by the cogeneration system and alternative treatment processes for the waste produced by the technology were compared. Despite the limitation of the research (results based on scaling up experimental data by modeling), impact assessment results are promising and sufficiently robust, as shown by Monte Carlo analysis. The TEKNE technology may become an interesting solution for the problem of ASR management: Besides representing an alternative to landfill disposal, the energy produced could avoid significant impacts on fossil resources depletion (a plant of 40,000 tons/y capacity could produce ∼ 147,000 GJ/yr, covering the annual need of ∼ 13,500 households). PMID

  8. Life cycle assessment of hydrogen production from S-I thermochemical process coupled to a high temperature gas reactor

    SciTech Connect

    Giraldi, M. R.; Francois, J. L.; Castro-Uriegas, D.

    2012-07-01

    The purpose of this paper is to quantify the greenhouse gas (GHG) emissions associated to the hydrogen produced by the sulfur-iodine thermochemical process, coupled to a high temperature nuclear reactor, and to compare the results with other life cycle analysis (LCA) studies on hydrogen production technologies, both conventional and emerging. The LCA tool was used to quantify the impacts associated with climate change. The product system was defined by the following steps: (i) extraction and manufacturing of raw materials (upstream flows), (U) external energy supplied to the system, (iii) nuclear power plant, and (iv) hydrogen production plant. Particular attention was focused to those processes where there was limited information from literature about inventory data, as the TRISO fuel manufacture, and the production of iodine. The results show that the electric power, supplied to the hydrogen plant, is a sensitive parameter for GHG emissions. When the nuclear power plant supplied the electrical power, low GHG emissions were obtained. These results improve those reported by conventional hydrogen production methods, such as steam reforming. (authors)

  9. Life cycle assessment of the transesterification double step process for biodiesel production from refined soybean oil in Brazil.

    PubMed

    Carvalho, Monica; da Silva, Elson Santos; Andersen, Silvia L F; Abrahão, Raphael

    2016-06-01

    Biodiesel has been attracting considerable attention as being a renewable, biodegradable, and nontoxic fuel that can contribute to the solution of some energy issues as it presents potential to help mitigate climate change. The Life Cycle Assessment of biodiesel from soybean oil (transesterification double step process) was carried out herein. A pilot plant was considered, designed to produce 72 L of biodiesel in daily continuous flow, throughout a lifetime of 15 years (8000 annual hours). The materials and equipment utilized in the construction of the plant were considered as well as the energy and substances required for the production of biodiesel. Environmental impact assessment method IPCC 2013 GWP 100a was utilized within the SimaPro software to express the final result in kg CO2-equivalent. The results quantified the CO2 emissions associated with biodiesel production throughout the lifetime of the production plant (15 years), resulting in a total value of 1,441,426.05 kg CO2-eq. (96,095.07 kg CO2-eq. per year), which was equivalent to 4.01 kg CO2-eq. per liter of biodiesel produced. Decrease of environmental loads associated with the production of biodiesel could include improvements on the handling of biomass agriculture and on the technology production of biodiesel.

  10. Life cycle assessment of the transesterification double step process for biodiesel production from refined soybean oil in Brazil.

    PubMed

    Carvalho, Monica; da Silva, Elson Santos; Andersen, Silvia L F; Abrahão, Raphael

    2016-06-01

    Biodiesel has been attracting considerable attention as being a renewable, biodegradable, and nontoxic fuel that can contribute to the solution of some energy issues as it presents potential to help mitigate climate change. The Life Cycle Assessment of biodiesel from soybean oil (transesterification double step process) was carried out herein. A pilot plant was considered, designed to produce 72 L of biodiesel in daily continuous flow, throughout a lifetime of 15 years (8000 annual hours). The materials and equipment utilized in the construction of the plant were considered as well as the energy and substances required for the production of biodiesel. Environmental impact assessment method IPCC 2013 GWP 100a was utilized within the SimaPro software to express the final result in kg CO2-equivalent. The results quantified the CO2 emissions associated with biodiesel production throughout the lifetime of the production plant (15 years), resulting in a total value of 1,441,426.05 kg CO2-eq. (96,095.07 kg CO2-eq. per year), which was equivalent to 4.01 kg CO2-eq. per liter of biodiesel produced. Decrease of environmental loads associated with the production of biodiesel could include improvements on the handling of biomass agriculture and on the technology production of biodiesel. PMID:26903132

  11. Life cycle toxicity assessment of pesticides used in integrated and organic production of oranges in the Comunidad Valenciana, Spain.

    PubMed

    Juraske, Ronnie; Sanjuán, Neus

    2011-02-01

    The relative impacts of 25 pesticides including acaricides, fungicides, herbicides, insecticides, and post-harvest fungicides, used in the production of oranges in Spain were assessed with current life cycle impact assessment (LCIA) tools. Chemical specific concentrations were combined with pesticide emission data and information on chemical toxicity to assess human toxicity and freshwater ecotoxicity impacts. As a case study, the relative impacts of two orange production systems in the region of Valencia, integrated pest management (IP) and organic production (OP), were assessed. The evaluation of active ingredients showed that on average acaricides have the highest human toxicity impact scores, while for freshwater ecotoxicity insecticides show the highest impact. In both impact categories the lowest impact scores were calculated for herbicides. In the production of 1 kg of orange fruits, where several kinds of pesticides are combined, results show that post-harvest fungicides can contribute more than 95% to the aggregate human toxicity impacts. More than 85% of aquatic ecotoxicity is generated by fungicides applied before harvest. The potential to reduce impacts on freshwater ecosystems is seven orders of magnitude, while impacts on human health can be reduced by two orders of magnitude. Hence, this stresses the importance of a careful pre-selection of active ingredients. In both impact categories, organic production represents the least toxic pest-control method.

  12. Greenhouse gas life cycle assessment of products arising from the rendering of mammalian animal byproducts in the UK.

    PubMed

    Ramirez, Angel D; Humphries, Andrea C; Woodgate, Stephen L; Wilkinson, Robert G

    2012-01-01

    Animal byproducts (ABP) are unavoidable byproduct of meat production that are categorized under EU legislation into category 1, 2, and 3 materials, which are normally treated by rendering. Rendering is a thermal process that produces rendered fat and protein. Heat is provided from the combustion of natural gas and self-produced rendered fat. The main objectives of the study were (i) to assess energy intensity in the UK rendering industry, and (ii) to quantify the greenhouse gas emissions associated with the production of mammalian rendered products using life cycle assessment. Thermal energy requirements were 2646 and 1357 kJ/kg, whereas electricity requirements were 260 and 375 kJ/kg for category 1 and 3 ABP respectively. Fossil CO(2) emissions were -0.77 and 0.15 kg CO(2)e/kg category 1 and 3 mammalian rendered fat respectively and 0.15 kg CO(2)e/kg processed animal protein. These were low relative to vegetable products such as palm oil and soya bean meal because (i) ABP were considered wastes that do not incur the environmental burden of their production, and (ii) the rendering process produces biofuels that can be used to generate energy that can be used to offset the use of fossil fuels in other systems.

  13. Anticipatory Life Cycle Analysis of In Vitro Biomass Cultivation for Cultured Meat Production in the United States.

    PubMed

    Mattick, Carolyn S; Landis, Amy E; Allenby, Braden R; Genovese, Nicholas J

    2015-10-01

    Cultured, or in vitro, meat consists of edible biomass grown from animal stem cells in a factory, or carnery. In the coming decades, in vitro biomass cultivation could enable the production of meat without the need to raise livestock. Using an anticipatory life cycle analysis framework, the study described herein examines the environmental implications of this emerging technology and compares the results with published impacts of beef, pork, poultry, and another speculative analysis of cultured biomass. While uncertainty ranges are large, the findings suggest that in vitro biomass cultivation could require smaller quantities of agricultural inputs and land than livestock; however, those benefits could come at the expense of more intensive energy use as biological functions such as digestion and nutrient circulation are replaced by industrial equivalents. From this perspective, large-scale cultivation of in vitro meat and other bioengineered products could represent a new phase of industrialization with inherently complex and challenging trade-offs.

  14. Energy efficiency and environmental performance of bioethanol production from sweet sorghum stem based on life cycle analysis.

    PubMed

    Wang, Mingxin; Chen, Yahui; Xia, Xunfeng; Li, Jun; Liu, Jianguo

    2014-07-01

    Life cycle analysis method was used to evaluate the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem in China. The scope covers three units, including plant cultivation, feedstock transport, and bioethanol conversion. Results show that the net energy ratio was 1.56 and the net energy gain was 8.37 MJ/L. Human toxicity was identified as the most significant negative environmental impact, followed by eutrophication and acidification. Steam generation in the bioethanol conversion unit contributed 82.28% and 48.26% to total human toxicity and acidification potential, respectively. Fertilizers loss from farmland represented 67.23% of total eutrophication potential. The results were significantly affected by the inventory allocation methods, vinasse reusing approaches, and feedstock yields. Reusing vinasse as fuel for steam generation and better cultivation practice to control fertilizer loss could significantly contribute to enhance the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem. PMID:24787319

  15. Energy efficiency and environmental performance of bioethanol production from sweet sorghum stem based on life cycle analysis.

    PubMed

    Wang, Mingxin; Chen, Yahui; Xia, Xunfeng; Li, Jun; Liu, Jianguo

    2014-07-01

    Life cycle analysis method was used to evaluate the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem in China. The scope covers three units, including plant cultivation, feedstock transport, and bioethanol conversion. Results show that the net energy ratio was 1.56 and the net energy gain was 8.37 MJ/L. Human toxicity was identified as the most significant negative environmental impact, followed by eutrophication and acidification. Steam generation in the bioethanol conversion unit contributed 82.28% and 48.26% to total human toxicity and acidification potential, respectively. Fertilizers loss from farmland represented 67.23% of total eutrophication potential. The results were significantly affected by the inventory allocation methods, vinasse reusing approaches, and feedstock yields. Reusing vinasse as fuel for steam generation and better cultivation practice to control fertilizer loss could significantly contribute to enhance the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem.

  16. Anticipatory Life Cycle Analysis of In Vitro Biomass Cultivation for Cultured Meat Production in the United States.

    PubMed

    Mattick, Carolyn S; Landis, Amy E; Allenby, Braden R; Genovese, Nicholas J

    2015-10-01

    Cultured, or in vitro, meat consists of edible biomass grown from animal stem cells in a factory, or carnery. In the coming decades, in vitro biomass cultivation could enable the production of meat without the need to raise livestock. Using an anticipatory life cycle analysis framework, the study described herein examines the environmental implications of this emerging technology and compares the results with published impacts of beef, pork, poultry, and another speculative analysis of cultured biomass. While uncertainty ranges are large, the findings suggest that in vitro biomass cultivation could require smaller quantities of agricultural inputs and land than livestock; however, those benefits could come at the expense of more intensive energy use as biological functions such as digestion and nutrient circulation are replaced by industrial equivalents. From this perspective, large-scale cultivation of in vitro meat and other bioengineered products could represent a new phase of industrialization with inherently complex and challenging trade-offs. PMID:26383898

  17. Short-term effects of salinity reduction and drainage on salt-marsh biogeochemical cycling and Spartina (Cordgrass) production

    USGS Publications Warehouse

    Portnoy, J.W.; Valiela, I.

    1997-01-01

    To assess the biogeochemical effects of tidal restrictions on salt-marsh sulfur cycling and plant growth, cores of short-form Spartina alterniflora peat were desalinated and kept either waterlogged or drained in greenhouse microcosms. Changes in net Spartina production, and porewater and solid phase chemistry of treated cores were compared to natural conditions in the field collection site over a 21-mo period. Net production among treatments increased significantly in drained and waterlogged peat compared to field conditions during the first growing season. Constantly high sulfide in waterlogged cores accompanied reduced plant growth. Aeration invigorated growth in drained cores but led to oxidization of sulfide minerals and to lowered pH. During the second growing season, growth declined in the drained treatment, probably because of acidification and decreased dissolved inorganic nitrogen. Results are pertinent to the success of current wetland protection and restoration activities in the coastal zone.

  18. Nitrogen cycling and N2O production in the water column of the ferruginous meromictic Lake La Cruz (Spain)

    NASA Astrophysics Data System (ADS)

    Tischer, Jana; Zopfi, Jakob; Frame, Caitlin H.; Jegge, Corinne; Kirsten, Oswald; Andreas, Brand; Miracle, Maria R.; Vicente, Eduardo; Lehmann, Moritz F.

    2016-04-01

    Ferruginous meromictic lakes are rare systems, considered potential modern analogues for an ancient Archean ferruginous Ocean. They may therefore represent valuable model ecosystems to study biogeochemical processes of early Earth history, in particular, the interaction between the iron (Fe) and other element cycles such as the complex nitrogen (N) cycle. In context of its exceptional water chemistry, we studied the N-cycling in the meromictic, ferruginous Lake La Cruz in the Central Iberian Ranges in Spain, combining i) general water column chemistry and detailed N speciation ii) stable isotope composition and intramolecular 15N distributions (site preference) of dissolved N2O and iii) 15N-isotope label incubation experiments, to identify and quantify biotic and abiotic N2O and N2 production pathways. Nitrification was identified as the main N2O production mechanism in the oxic zone, based on the N2O concentration profile and the isomeric composition of N2O (site preference = 24.7) at the depth of maximum concentration relative to the surface water. A second N2O peak of 23 nmol/L was observed within the chemocline, and relatively low values for the δ15N-N2O (-1.1) and a site preference of 16.1‰ with respect to the oxic water column suggest that here incomplete (nitrifier) denitrification is the dominant N2O production pathway. However, based on the bulk dual N-versus-O isotope signature, other production mechanisms cannot be excluded at this point. Within the anoxic water column, N2O is consumed quantitiatively to N2, consistent with 15N-NO3- incubation experiments, showing denitrification (and anammox) activity below the redox transition zone. The overlap of Fe and N-species (N2O, NO2-) in the water column is small, therefore abiotic N2O production is most likely negligible. The planned analysis of the NO3- and NH4+ isotopic signatures will provide further insight into the origin of N2O. Additionally, molecular biological analyses will provide information on

  19. Nitrogen cycling and N2O production in the water column of the ferruginous meromictic Lake La Cruz (Spain)

    NASA Astrophysics Data System (ADS)

    Tischer, Jana; Zopfi, Jakob; Frame, Caitlin H.; Jegge, Corinne; Kirsten, Oswald; Andreas, Brand; Miracle, Maria R.; Vicente, Eduardo; Lehmann, Moritz F.

    2016-04-01

    Ferruginous meromictic lakes are rare systems, considered potential modern analogues for an ancient Archean ferruginous Ocean. They may therefore represent valuable model ecosystems to study biogeochemical processes of early Earth history, in particular, the interaction between the iron (Fe) and other element cycles such as the complex nitrogen (N) cycle. In context of its exceptional water chemistry, we studied the N-cycling in the meromictic, ferruginous Lake La Cruz in the Central Iberian Ranges in Spain, combining i) general water column chemistry and detailed N speciation ii) stable isotope composition and intramolecular 15N distributions (site preference) of dissolved N2O and iii) 15N-isotope label incubation experiments, to identify and quantify biotic and abiotic N2O and N2 production pathways. Nitrification was identified as the main N2O production mechanism in the oxic zone, based on the N2O concentration profile and the isomeric composition of N2O (site preference = 24.7) at the depth of maximum concentration relative to the surface water. A second N2O peak of 23 nmol/L was observed within the chemocline, and relatively low values for the δ15N-N2O (-1.1) and a site preference of 16.1‰ with respect to the oxic water column suggest that here incomplete (nitrifier) denitrification is the dominant N2O production pathway. However, based on the bulk dual N-versus-O isotope signature, other production mechanisms cannot be excluded at this point. Within the anoxic water column, N2O is consumed quantitiatively to N2, consistent with 15N-NO3‑ incubation experiments, showing denitrification (and anammox) activity below the redox transition zone. The overlap of Fe and N-species (N2O, NO2‑) in the water column is small, therefore abiotic N2O production is most likely negligible. The planned analysis of the NO3‑ and NH4+ isotopic signatures will provide further insight into the origin of N2O. Additionally, molecular biological analyses will provide

  20. Hydrogen-or-Fossil-Combustion Nuclear Combined-Cycle Systems for Base- and Peak-Load Electricity Production

    SciTech Connect

    Forsberg, Charles W; Conklin, Jim

    2007-09-01

    A combined-cycle power plant is described that uses (1) heat from a high-temperature nuclear reactor to meet base-load electrical demands and (2) heat from the same high-temperature reactor and burning natural gas, jet fuel, or hydrogen to meet peak-load electrical demands. For base-load electricity production, fresh air is compressed; then flows through a heat exchanger, where it is heated to between 700 and 900 C by heat provided by a high-temperature nuclear reactor via an intermediate heat-transport loop; and finally exits through a high-temperature gas turbine to produce electricity. The hot exhaust from the Brayton-cycle gas turbine is then fed to a heat recovery steam generator that provides steam to a steam turbine for added electrical power production. To meet peak electricity demand, the air is first compressed and then heated with the heat from a high-temperature reactor. Natural gas, jet fuel, or hydrogen is then injected into the hot air in a combustion chamber, combusts, and heats the air to 1300 C-the operating conditions for a standard natural-gas-fired combined-cycle plant. The hot gas then flows through a gas turbine and a heat recovery steam generator before being sent to the exhaust stack. The higher temperatures increase the plant efficiency and power output. If hydrogen is used, it can be produced at night using energy from the nuclear reactor and stored until needed. With hydrogen serving as the auxiliary fuel for peak power production, the electricity output to the electric grid can vary from zero (i.e., when hydrogen is being produced) to the maximum peak power while the nuclear reactor operates at constant load. Because nuclear heat raises air temperatures above the auto-ignition temperatures of the various fuels and powers the air compressor, the power output can be varied rapidly (compared with the capabilities of fossil-fired turbines) to meet spinning reserve requirements and stabilize the electric grid. This combined cycle uses the

  1. Cost structures and life cycle impacts of algal biomass and biofuel production

    NASA Astrophysics Data System (ADS)

    Christiansen, Katrina Lea

    2011-12-01

    Development and extraction of energy sources, energy production and energy use have huge economic, environmental and geopolitical impacts. Increasing energy demands in tandem with reductions in fossil fuel production has led to significant investments in research into alternative forms of energy. One that is promising but yet not commercially established is the production of biofuel from algae. This research quantitatively assessed the potential of algae biofuel production by examining its cost and environmental impacts. First, two models developed by the RAND corporation were employed to assess Cost Growth defined as the ratio of actual costs to estimated costs, and Plant Performance defined as the ratio of actual production levels to design performance, of three algal biofuel production technologies. The three algal biofuel production technologies examined to open raceway ponds (ORPs), photobioreactors (PBRs), and a system that couples PBRs to ORPs (PBR-ORPs). Though these analyses lack precision due to uncertainty, the results highlight the risks associated with implementing algal biofuel systems, as all scenarios examined were predicted to have Cost Growth, ranging from 1.2 to 1.8, and Plant Performance was projected as less than 50% of design performance for all cases. Second, the Framework the Evaluation of Biomass Energy Feedstocks (FEBEF) was used to assess the cost and environmental impacts of biodiesel produced from three algal production technologies. When these results were compared with ethanol from corn and biodiesel from soybeans, biodiesel from algae produced from the different technologies were estimated to be more expensive, suffered from low energy gains, and did not result in lower greenhouse gas emissions. To identify likely routes to making algal biofuels more competitive, a third study was undertaken. In this case, FEBEF was employed to examine pinch-points (defined as the most costly, energy consuming, greenhouse gas producing processes), in

  2. Carbon cycling and net ecosystem production at an early stage of secondary succession in an abandoned coppice forest.

    PubMed

    Ohtsuka, Toshiyuki; Shizu, Yoko; Nishiwaki, Ai; Yashiro, Yuichiro; Koizumi, Hiroshi

    2010-07-01

    Secondary mixed forests are one of the dominant forest cover types in human-dominated temperate regions. However, our understanding of how secondary succession affects carbon cycling and carbon sequestration in these ecosystems is limited. We studied carbon cycling and net ecosystem production (NEP) over 4 years (2004-2008) in a cool-temperate deciduous forest at an early stage of secondary succession (18 years after clear-cutting). Net primary production of the 18-year-old forest in this study was 5.2 tC ha(-1 )year(-1), including below-ground coarse roots; this was partitioned into 2.5 tC ha(-1 )year(-1) biomass increment, 1.6 tC ha(-1 )year(-1) foliage litter, and 1.0 tC ha(-1 )year(-1) other woody detritus. The total amount of annual soil surface CO(2) efflux was 6.8 tC ha(-1 )year(-1), which included root respiration (1.9 tC ha(-1 )year(-1)) and heterotrophic respiration (RH) from soils (4.9 tC ha(-1 )year(-1)). The 18-year forest at this study site exhibited a great increase in biomass pool as a result of considerable total tree growth and low mortality of tree stems. In contrast, the soil organic matter (SOM) pool decreased markedly (-1.6 tC ha(-1 )year(-1)), although further study of below-ground detritus production and RH of SOM decomposition is needed. This young 18-year forest was a weak carbon sink (0.9 tC ha(-1 )year(-1)) at this stage of secondary succession. The NEP of this 18-year forest is likely to increase gradually because biomass increases with tree growth and with the improvement of the SOM pool through increasing litter and dead wood production with stand development.

  3. Carbon cycling and net ecosystem production at an early stage of secondary succession in an abandoned coppice forest.

    PubMed

    Ohtsuka, Toshiyuki; Shizu, Yoko; Nishiwaki, Ai; Yashiro, Yuichiro; Koizumi, Hiroshi

    2010-07-01

    Secondary mixed forests are one of the dominant forest cover types in human-dominated temperate regions. However, our understanding of how secondary succession affects carbon cycling and carbon sequestration in these ecosystems is limited. We studied carbon cycling and net ecosystem production (NEP) over 4 years (2004-2008) in a cool-temperate deciduous forest at an early stage of secondary succession (18 years after clear-cutting). Net primary production of the 18-year-old forest in this study was 5.2 tC ha(-1 )year(-1), including below-ground coarse roots; this was partitioned into 2.5 tC ha(-1 )year(-1) biomass increment, 1.6 tC ha(-1 )year(-1) foliage litter, and 1.0 tC ha(-1 )year(-1) other woody detritus. The total amount of annual soil surface CO(2) efflux was 6.8 tC ha(-1 )year(-1), which included root respiration (1.9 tC ha(-1 )year(-1)) and heterotrophic respiration (RH) from soils (4.9 tC ha(-1 )year(-1)). The 18-year forest at this study site exhibited a great increase in biomass pool as a result of considerable total tree growth and low mortality of tree stems. In contrast, the soil organic matter (SOM) pool decreased markedly (-1.6 tC ha(-1 )year(-1)), although further study of below-ground detritus production and RH of SOM decomposition is needed. This young 18-year forest was a weak carbon sink (0.9 tC ha(-1 )year(-1)) at this stage of secondary succession. The NEP of this 18-year forest is likely to increase gradually because biomass increases with tree growth and with the improvement of the SOM pool through increasing litter and dead wood production with stand development. PMID:20033468

  4. Life cycle energy and greenhouse gas emissions for an ethanol production process based on blue-green algae.

    PubMed

    Luo, Dexin; Hu, Zushou; Choi, Dong Gu; Thomas, Valerie M; Realff, Matthew J; Chance, Ronald R

    2010-11-15

    Ethanol can be produced via an intracellular photosynthetic process in cyanobacteria (blue-green algae), excreted through the cell walls, collected from closed photobioreactors as a dilute ethanol-in-water solution, and purified to fuel grade ethanol. This sequence forms the basis for a biofuel production process that is currently being examined for its commercial potential. In this paper, we calculate the life cycle energy and greenhouse gas emissions for three different system scenarios for this proposed ethanol production process, using process simulations and thermodynamic calculations. The energy required for ethanol separation increases rapidly for low initial concentrations of ethanol, and, unlike other biofuel systems, there is little waste biomass available to provide process heat and electricity to offset those energy requirements. The ethanol purification process is a major consumer of energy and a significant contributor to the carbon footprint. With a lead scenario based on a natural-gas-fueled combined heat and power system to provide process electricity and extra heat and conservative assumptions around the ethanol separation process, the net life cycle energy consumption, excluding photosynthesis, ranges from 0.55 MJ/MJ(EtOH) down to 0.20 MJ/ MJ(EtOH), and the net life cycle greenhouse gas emissions range from 29.8 g CO₂e/MJ(EtOH) down to 12.3 g CO₂e/MJ(EtOH) for initial ethanol concentrations from 0.5 wt % to 5 wt %. In comparison to gasoline, these predicted values represent 67% and 87% reductions in the carbon footprint for this ethanol fuel on a energy equivalent basis. Energy consumption and greenhouse gas emissions can be further reduced via employment of higher efficiency heat exchangers in ethanol purification and/ or with use of solar thermal for some of the process heat. PMID:20968295

  5. Implications of incorporating N cycling and N limitations on primary production in an individual-based dynamic vegetation model

    NASA Astrophysics Data System (ADS)

    Smith, B.; Wårlind, D.; Arneth, A.; Hickler, T.; Leadley, P.; Siltberg, J.; Zaehle, S.

    2014-04-01

    The LPJ-GUESS dynamic vegetation model uniquely combines an individual- and patch-based representation of vegetation dynamics with ecosystem biogeochemical cycling from regional to global scales. We present an updated version that includes plant and soil N dynamics, analysing the implications of accounting for C-N interactions on predictions and performance of the model. Stand structural dynamics and allometric scaling of tree growth suggested by global databases of forest stand structure and development were well reproduced by the model in comparison to an earlier multi-model study. Accounting for N cycle dynamics improved the goodness of fit for broadleaved forests. N limitation associated with low N-mineralisation rates reduces productivity of cold-climate and dry-climate ecosystems relative to mesic temperate and tropical ecosystems. In a model experiment emulating free-air CO2 enrichment (FACE) treatment for forests globally, N limitation associated with low N-mineralisation rates of colder soils reduces CO2 enhancement of net primary production (NPP) for boreal forests, while some temperate and tropical forests exhibit increased NPP enhancement. Under a business-as-usual future climate and emissions scenario, ecosystem C storage globally was projected to increase by ca. 10%; additional N requirements to match this increasing ecosystem C were within the high N supply limit estimated on stoichiometric grounds in an earlier study. Our results highlight the importance of accounting for C-N interactions in studies of global terrestrial N cycling, and as a basis for understanding mechanisms on local scales and in different regional contexts.

  6. Life cycle energy and greenhouse gas emissions for an ethanol production process based on blue-green algae.

    PubMed

    Luo, Dexin; Hu, Zushou; Choi, Dong Gu; Thomas, Valerie M; Realff, Matthew J; Chance, Ronald R

    2010-11-15

    Ethanol can be produced via an intracellular photosynthetic process in cyanobacteria (blue-green algae), excreted through the cell walls, collected from closed photobioreactors as a dilute ethanol-in-water solution, and purified to fuel grade ethanol. This sequence forms the basis for a biofuel production process that is currently being examined for its commercial potential. In this paper, we calculate the life cycle energy and greenhouse gas emissions for three different system scenarios for this proposed ethanol production process, using process simulations and thermodynamic calculations. The energy required for ethanol separation increases rapidly for low initial concentrations of ethanol, and, unlike other biofuel systems, there is little waste biomass available to provide process heat and electricity to offset those energy requirements. The ethanol purification process is a major consumer of energy and a significant contributor to the carbon footprint. With a lead scenario based on a natural-gas-fueled combined heat and power system to provide process electricity and extra heat and conservative assumptions around the ethanol separation process, the net life cycle energy consumption, excluding photosynthesis, ranges from 0.55 MJ/MJ(EtOH) down to 0.20 MJ/ MJ(EtOH), and the net life cycle greenhouse gas emissions range from 29.8 g CO₂e/MJ(EtOH) down to 12.3 g CO₂e/MJ(EtOH) for initial ethanol concentrations from 0.5 wt % to 5 wt %. In comparison to gasoline, these predicted values represent 67% and 87% reductions in the carbon footprint for this ethanol fuel on a energy equivalent basis. Energy consumption and greenhouse gas emissions can be further reduced via employment of higher efficiency heat exchangers in ethanol purification and/ or with use of solar thermal for some of the process heat.

  7. Modulation of fatty acid metabolism and tricarboxylic acid cycle to enhance the lipstatin production through medium engineering in Streptomyces toxytricini.

    PubMed

    Kumar, Punit; Dubey, Kashyap Kumar

    2016-08-01

    This work investigated the potential of medium engineering to obtain maximum biomass, non-conventional carbon sources for lipstatin production and modulation of tricarboxylic acid (TCA) cycle to promote lipstatin synthesis. It was found that 2:3 carbon and nitrogen ratio, produced maximum biomass of 7.9g/L in growth medium and 6.6g/L in pre-seed medium. Among the studied non-conventional carbon sources i.e., soya flour 40g/L and sesame oil 30mL/L were found producing 1109.37mg/L (1.24-fold of control) and 1196.75mg/L (1.34-fold of control) lipstatin respectively. Supplementation of TCA cycle intermediates revealed that NADH and succinic acid showed lipstatin production to 1132.99mg/L and 1171.10mg/L respectively. Experimental outcome was validated in 7L bioreactor and produced 2242.63mg/L lipstatin which was ∼14% higher than shake flask. PMID:26897471

  8. Life cycle assessment of the production of hydrogen and transportation fuels from corn stover via fast pyrolysis

    NASA Astrophysics Data System (ADS)

    Zhang, Yanan; Hu, Guiping; Brown, Robert C.

    2013-06-01

    This life cycle assessment evaluates and quantifies the environmental impacts of the production of hydrogen and transportation fuels from the fast pyrolysis and upgrading of corn stover. Input data for this analysis come from Aspen Plus modeling, a GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model database and a US Life Cycle Inventory Database. SimaPro 7.3 software is employed to estimate the environmental impacts. The results indicate that the net fossil energy input is 0.25 MJ and 0.23 MJ per km traveled for a light-duty vehicle fueled by gasoline and diesel fuel, respectively. Bio-oil production requires the largest fossil energy input. The net global warming potential (GWP) is 0.037 kg CO2eq and 0.015 kg CO2eq per km traveled for a vehicle fueled by gasoline and diesel fuel, respectively. Vehicle operations contribute up to 33% of the total positive GWP, which is the largest greenhouse gas footprint of all the unit processes. The net GWPs in this study are 88% and 94% lower than for petroleum-based gasoline and diesel fuel (2005 baseline), respectively. Biomass transportation has the largest impact on ozone depletion among all of the unit processes. Sensitivity analysis shows that fuel economy, transportation fuel yield, bio-oil yield, and electricity consumption are the key factors that influence greenhouse gas emissions.

  9. System Evaluations and Life-Cycle Cost Analyses for High-Temperature Electrolysis Hydrogen Production Facilities

    SciTech Connect

    Edwin A. Harvego; James E. O'Brien; Michael G. McKellar

    2012-05-01

    This report presents results of system evaluations and lifecycle cost analyses performed for several different commercial-scale high-temperature electrolysis (HTE) hydrogen production concepts. The concepts presented in this report rely on grid electricity and non-nuclear high-temperature process heat sources for the required energy inputs. The HYSYS process analysis software was used to evaluate both central plant designs for large-scale hydrogen production (50,000 kg/day or larger) and forecourt plant designs for distributed production and delivery at about 1,500 kg/day. The HYSYS software inherently ensures mass and energy balances across all components and it includes thermodynamic data for all chemical species. The optimized designs described in this report are based on analyses of process flow diagrams that included realistic representations of fluid conditions and component efficiencies and operating parameters for each of the HTE hydrogen production configurations analyzed. As with previous HTE system analyses performed at the INL, a custom electrolyzer model was incorporated into the overall process flow sheet. This electrolyzer model allows for the determination of the average Nernst potential, cell operating voltage, gas outlet temperatures, and electrolyzer efficiency for any specified inlet steam, hydrogen, and sweep-gas flow rates, current density, cell active area, and external heat loss or gain. The lifecycle cost analyses were performed using the H2A analysis methodology developed by the Department of Energy (DOE) Hydrogen Program. This methodology utilizes spreadsheet analysis tools that require detailed plant performance information (obtained from HYSYS), along with financial and cost information to calculate lifecycle costs. There are standard default sets of assumptions that the methodology uses to ensure consistency when comparing the cost of different production or plant design options. However, these assumptions may also be varied within the

  10. Crustal-scale architecture and segmentation of the Argentine margin and its conjugate off South Africa

    NASA Astrophysics Data System (ADS)

    Blaich, Olav A.; Faleide, Jan Inge; Tsikalas, Filippos; Franke, Dieter; León, Enric

    2009-07-01

    Integration of regional seismic reflection and refraction profiles and potential field data across the Argentine margin and its conjugate off South Africa, complemented by crustal-scale gravity modelling, is used to reveal and illustrate the whole-crust architecture, onshore-offshore crustal structure correlations, the character of the continent-ocean boundary/transition and the relationship of crustal structure to regional variation of potential field anomalies. The study reveals, within these two provinces, distinct along-margin structural and magmatic changes that are spatially related to a number of conjugate transfer systems governing the margin segmentation and evolution, clearly implying structural inheritance. In particular, the Colorado transfer system on the Argentina margin, marks a distinct along-margin boundary in the distribution and volume of breakup-related magmatism. Similarly, the Hope transfer system on the conjugate South Africa margin also marks a distinct along-margin transition from a zone of relative magnetic quiescence to a zone of prominent magnetic anomalies. Furthermore, the study indicates that the `G-magnetic anomaly' along the South Africa margin probably defines the eastern limit of the continent-ocean transition (COT) rather than a discrete continent-ocean boundary (COB). Potential field plate reconstructions of the South Atlantic suggest conjugate margin asymmetry, characterized by a rather broad Argentine margin conjugate to a narrow South Africa margin. In detail, the Argentine margin is characterized by a sharp and relatively constant COT, whereas the COT along the conjugate South Africa margin is considerably wider. An along-strike tectonomagmatic asymmetry variation is also observed and is expressed by the northward increase in width of the COT on the South African margin. The study clearly shows that integration of regional seismic reflection and refraction profiles, potential field data and gravity modelling provide a

  11. Hantavirus reservoir Oligoryzomys longicaudatus spatial distribution sensitivity to climate change scenarios in Argentine Patagonia

    PubMed Central

    Carbajo, Aníbal E; Vera, Carolina; González, Paula LM

    2009-01-01

    Background Oligoryzomys longicaudatus (colilargo) is the rodent responsible for hantavirus pulmonary syndrome (HPS) in Argentine Patagonia. In past decades (1967–1998), trends of precipitation reduction and surface air temperature increase have been observed in western Patagonia. We explore how the potential distribution of the hantavirus reservoir would change under different climate change scenarios based on the observed trends. Methods Four scenarios of potential climate change were constructed using temperature and precipitation changes observed in Argentine Patagonia between 1967 and 1998: Scenario 1 assumed no change in precipitation but a temperature trend as observed; scenario 2 assumed no changes in temperature but a precipitation trend as observed; Scenario 3 included changes in both temperature and precipitation trends as observed; Scenario 4 assumed changes in both temperature and precipitation trends as observed but doubled. We used a validated spatial distribution model of O. longicaudatus as a function of temperature and precipitation. From the model probability of the rodent presence was calculated for each scenario. Results If changes in precipitation follow previous trends, the probability of the colilargo presence would fall in the HPS transmission zone of northern Patagonia. If temperature and precipitation trends remain at current levels for 60 years or double in the future 30 years, the probability of the rodent presence and the associated total area of potential distribution would diminish throughout Patagonia; the areas of potential distribution for colilargos would shift eastwards. These results suggest that future changes in Patagonia climate may lower transmission risk through a reduction in the potential distribution of the rodent reservoir. Conclusion According to our model the rates of temperature and precipitation changes observed between 1967 and 1998 may produce significant changes in the rodent distribution in an equivalent

  12. A life-cycle approach to low-invasion potential bioenergy production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing demand for energy has increased economic incentives to develop and deploy novel bioenergy crops for biomass production. Similarities in plant traits between many candidate bioenergy crops and known invasive species have raised concerns about the potential for bioenergy crops to escape pro...

  13. The Impacts of Miscanthus X gianteus Production on the Midwestern U.S. Hydrologic Cycle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The need for renewable energy to offset fossil fuel dependence and greenhouse gas emissions is increasing, with the majority of U.S. renewable energy production focused currently on replacing gasoline with corn ethanol. A growing body of research indicates that it may not be beneficial or even possi...

  14. Carbon and Water cycling in Southern Great Plains ecosystems converted to switchgrass production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report here the initiation of a multi-disciplinary, integrative program to investigate the effects of conversion of traditional southern Great Plains pasture and wheat systems to switchgrass (Panicum virgatum L.) production. The project is based at the USDA-ARS Southern Plains Range Research Stat...

  15. Evaluating Consumer Product Life Cycle Sustainability with Integrated Metrics: A Paper Towel Case Study

    EPA Science Inventory

    Integrated sustainability metrics provide an enriched set of information to inform decision-making. However, such approaches are rarely used to assess product supply chains. In this work, four integrated metrics—presented in terms of land, resources, value added, and stability—ar...

  16. The use of microalgae and their culture medium for biogas production in an integrated cycle.

    PubMed

    Formagini, E L; Marques, F R; Serejo, M L; Paulo, P L; Boncz, M A

    2014-01-01

    Vinasse is a residue produced in large quantities as a sub-product of ethanol production. Anaerobic digestion of vinasse can yield large amounts of biogas, but often difficulties arise in maintaining stable operation, due to the acidity of the material (which has a pH between 3.5 and 5) and a strong tendency to further acidification. Anaerobically digested vinasse can be used as part of a culture medium for microalgae cultivation, for the production of biodiesel and other compounds, whilst the excess CO2 produced in the ethanol fermentation can be used to stimulate algal growth. During algae cultivation, the pH of the culture medium has a strong tendency to increase; therefore, recycling of the spent culture medium or the concentrated algae suspension to the anaerobic digester treating vinasse was considered an option for pH stabilization there. Batch tests, however, showed that alkalinity of the spent culture broth, in spite of its high pH, is too low (only 350 mgCaCO3L(-1)) to help stabilise the pH of vinasse digestion. Alkalinity of the algae suspension is higher and digestion of a mixture of vinasse and a suspension of algae results in efficient biogas production, but still the alkalinity is insufficient to stabilise the pH in a range suitable for methanogenic microorganisms; hence, the addition of additional alkalinity, for instance as sodium bicarbonate or urea, remains necessary. PMID:24622540

  17. ``You are what you eat'': Diet modifies cuticular hydrocarbons and nestmate recognition in the Argentine ant, Linepithema humile

    NASA Astrophysics Data System (ADS)

    Liang, D.; Silverman, J.

    2000-10-01

    Nestmate recognition plays a key role in the behavior and evolution of social insects. We demonstrated that hydrocarbons are the chemical cues used in Argentine ant, Linepithema humile, nestmate recognition, and that these hydrocarbons can be acquired from insect prey. Consequently, Argentine ant cuticular hydrocarbon patterns reveal the same hydrocarbons present in their diet. Diet alters both the recognition cues present on the cuticular surface and the response of nestmates to this new colony odor, resulting in aggression between former nestmates reared on different insect prey.

  18. Predicting the environmental impacts of chicken systems in the United Kingdom through a life cycle assessment: broiler production systems.

    PubMed

    Leinonen, I; Williams, A G; Wiseman, J; Guy, J; Kyriazakis, I

    2012-01-01

    The aim of this study was to apply the life cycle assessment (LCA) method, from cradle to gate, to quantify the environmental burdens per 1,000 kg of expected edible carcass weight in the 3 main broiler production systems in the United Kingdom: 1) standard indoor, 2) free range, and 3) organic, and to identify the main components of these burdens. The LCA method evaluates production systems logically to account for all inputs and outputs that cross a specified system boundary, and it relates these to the useful outputs. The analysis was based on an approach that applied a structural model for the UK broiler industry and mechanistic submodels for animal performance, crop production, and major nutrient flows. Simplified baseline feeds representative of those used by the UK broiler industry were used. Typical UK figures for performance and mortality of birds and farm energy and material use were applied. Monte Carlo simulations were used to quantify the uncertainties in the outputs. The length of the production cycle was longer for free-range and organic systems compared with that of the standard indoor system, and as a result, the feed consumption and manure production per bird were higher in the free-range and organic systems. These differences had a major effect on the differences in environmental burdens between the systems. Feed production, processing, and transport resulted in greater overall environmental impacts than any other components of broiler production; for example, 65 to 81% of the primary energy use and 71 to 72% of the global warming potential of the system were due to these burdens. Farm gas and oil use had the second highest impact in primary energy use (12-25%) followed by farm electricity use. The direct use of gas, oil, and electricity were generally lower in free-range and organic systems compared with their use in the standard indoor system. Manure was the main component of acidification potential and also had a relatively high eutrophication

  19. Predicting the environmental impacts of chicken systems in the United Kingdom through a life cycle assessment: broiler production systems.

    PubMed

    Leinonen, I; Williams, A G; Wiseman, J; Guy, J; Kyriazakis, I

    2012-01-01

    The aim of this study was to apply the life cycle assessment (LCA) method, from cradle to gate, to quantify the environmental burdens per 1,000 kg of expected edible carcass weight in the 3 main broiler production systems in the United Kingdom: 1) standard indoor, 2) free range, and 3) organic, and to identify the main components of these burdens. The LCA method evaluates production systems logically to account for all inputs and outputs that cross a specified system boundary, and it relates these to the useful outputs. The analysis was based on an approach that applied a structural model for the UK broiler industry and mechanistic submodels for animal performance, crop production, and major nutrient flows. Simplified baseline feeds representative of those used by the UK broiler industry were used. Typical UK figures for performance and mortality of birds and farm energy and material use were applied. Monte Carlo simulations were used to quantify the uncertainties in the outputs. The length of the production cycle was longer for free-range and organic systems compared with that of the standard indoor system, and as a result, the feed consumption and manure production per bird were higher in the free-range and organic systems. These differences had a major effect on the differences in environmental burdens between the systems. Feed production, processing, and transport resulted in greater overall environmental impacts than any other components of broiler production; for example, 65 to 81% of the primary energy use and 71 to 72% of the global warming potential of the system were due to these burdens. Farm gas and oil use had the second highest impact in primary energy use (12-25%) followed by farm electricity use. The direct use of gas, oil, and electricity were generally lower in free-range and organic systems compared with their use in the standard indoor system. Manure was the main component of acidification potential and also had a relatively high eutrophication

  20. Biological productivity regime and associated N cycling in the vicinity of Kerguelen Island area, Southern Ocean

    NASA Astrophysics Data System (ADS)

    Cavagna, A. J.; Fripiat, F.; Elskens, M.; Dehairs, F.; Mangion, P.; Chirurgien, L.; Closset, I.; Lasbleiz, M.; Flores-Leiva, L.; Cardinal, D.; Leblanc, K.; Fernandez, C.; Lefèvre, D.; Oriol, L.; Blain, S.; Quéguiner, B.

    2014-12-01

    Although the Southern Ocean is considered a High Nutrient Low Chlorophyll area (HNLC), massive and recurrent blooms are observed over and downstream the Kerguelen Plateau. This mosaic of blooms is triggered by a higher iron supply resulting from the interaction between the Antarctic Circumpolar Current and the local bathymetry. Net primary production, N-uptake (NO3- and NH4+), and nitrification rates were measured at 8 stations in austral spring 2011 (October-November) during the KEOPS2 cruise in the Kerguelen area. Iron fertilization stimulates primary production, with integrated net primary production and growth rates much higher in the fertilized areas (up to 315 mmol C m-2 d-1 and up to 0.31 d-1, respectively) compared to the HNLC reference site (12 mmol C m-2 d-1 and 0.06 d-1, respectively). Primary production is mainly sustained by nitrate uptake, with f ratio (corresponding to NO3- uptake/(NO3- uptake + NH4+ uptake)) lying in the upper end of the observations for the Southern Ocean (up to 0.9). Unexpectedly, we report unprecedented rates of nitrification (up to ~3 mmol C m-2 d-1, with ~90% of them <1 mmol C m-2 d-1). It appears that nitrate is assimilated in the upper part of the mixed layer (coinciding with the euphotic layer) and regenerated in the lower parts. We suggest that such high contribution of nitrification to nitrate assimilation is driven by (i) a deep mixed layer, extending well below the euphotic layer, allowing nitrifiers to compete with phytoplankton for the assimilation of ammonium, (ii) extremely high rates of primary production for the Southern Ocean, stimulating the release of dissolved organic matter, and (iii) an efficient food web, allowing the reprocessing of organic N and the retention of nitrogen into the dissolved phase through ammonium, the substrate for nitrification.

  1. Exploring global changes in nitrogen and phosphorus cycles in agriculture induced by livestock production over the 1900-2050 period.

    PubMed

    Bouwman, Lex; Goldewijk, Kees Klein; Van Der Hoek, Klaas W; Beusen, Arthur H W; Van Vuuren, Detlef P; Willems, Jaap; Rufino, Mariana C; Stehfest, Elke

    2013-12-24

    Crop-livestock production systems are the largest cause of human alteration of the global nitrogen (N) and phosphorus (P) cycles. Our comprehensive spatially explicit inventory of N and P budgets in livestock and crop production systems shows that in the beginning of the 20th century, nutrient budgets were either balanced or surpluses were small; between 1900 and 1950, global soil N surplus almost doubled to 36 trillion grams (Tg) · y(-1) and P surplus increased by a factor of 8 to 2 Tg · y(-1). Between 1950 and 2000, the global surplus increased to 138 Tg · y(-1) of N and 11 Tg · y(-1) of P. Most surplus N is an environmental loss; surplus P is lost by runoff or accumulates as residual soil P. The International Assessment of Agricultural Knowledge, Science, and Technology for Development scenario portrays a world with a further increasing global crop (+82% for 2000-2050) and livestock production (+115%); despite rapidly increasing recovery in crop (+35% N recovery and +6% P recovery) and livestock (+35% N and P recovery) production, global nutrient surpluses continue to increase (+23% N and +54% P), and in this period, surpluses also increase in Africa (+49% N and +236% P) and Latin America (+75% N and +120% P). Alternative management of livestock production systems shows that combinations of intensification, better integration of animal manure in crop production, and matching N and P supply to livestock requirements can effectively reduce nutrient flows. A shift in human diets, with poultry or pork replacing beef, can reduce nutrient flows in countries with intensive ruminant production.

  2. Exploring global changes in nitrogen and phosphorus cycles in agriculture induced by livestock production over the 1900–2050 period

    PubMed Central

    Bouwman, Lex; Goldewijk, Kees Klein; Van Der Hoek, Klaas W.; Beusen, Arthur H. W.; Van Vuuren, Detlef P.; Willems, Jaap; Rufino, Mariana C.; Stehfest, Elke

    2013-01-01

    Crop-livestock production systems are the largest cause of human alteration of the global nitrogen (N) and phosphorus (P) cycles. Our comprehensive spatially explicit inventory of N and P budgets in livestock and crop production systems shows that in the beginning of the 20th century, nutrient budgets were either balanced or surpluses were small; between 1900 and 1950, global soil N surplus almost doubled to 36 trillion grams (Tg)·y−1 and P surplus increased by a factor of 8 to 2 Tg·y−1. Between 1950 and 2000, the global surplus increased to 138 Tg·y−1 of N and 11 Tg·y−1 of P. Most surplus N is an environmental loss; surplus P is lost by runoff or accumulates as residual soil P. The International Assessment of Agricultural Knowledge, Science, and Technology for Development scenario portrays a world with a further increasing global crop (+82% for 2000–2050) and livestock production (+115%); despite rapidly increasing recovery in crop (+35% N recovery and +6% P recovery) and livestock (+35% N and P recovery) production, global nutrient surpluses continue to increase (+23% N and +54% P), and in this period, surpluses also increase in Africa (+49% N and +236% P) and Latin America (+75% N and +120% P). Alternative management of livestock production systems shows that combinations of intensification, better integration of animal manure in crop production, and matching N and P supply to livestock requirements can effectively reduce nutrient flows. A shift in human diets, with poultry or pork replacing beef, can reduce nutrient flows in countries with intensive ruminant production. PMID:21576477

  3. A new species of Havelockia Pearson, 1903 from the Argentine Sea (Holothuroidea: Dendrochirotida: Sclerodactylidae).

    PubMed

    Martinez, Mariano I; Thandar, Ahmed S; Penchaszadeh, Pablo E

    2013-01-01

    Havelockia pegi sp. nov., is here described from shallow waters of the Argentine Sea. This new species is distinctive in the purple colouration of its tentacles, scarcity of body wall ossicles and the presence of rosette-shaped ossicles in both the introvert and the tentacles. It is not closely related to any of its congenors. This is the first record of a true sclerodactylid from Argentina. Thandarum hernandezi Martinez & Brogger, 2012, described in the family Sclerodactylidae, is now classified in the family Sclerothyonidae. PMID:24699619

  4. Equity during an economic crisis: financing of the Argentine health system.

    PubMed

    Cavagnero, Eleonora; Bilger, Marcel

    2010-07-01

    This article analyses the redistributive effect caused by health financing and the distribution of healthcare utilization in Argentina before and during the severe 2001/2002 economic crisis. Both dramatically changed during this period: the redistributive effect became much more positive and utilization shifted from pro-poor to pro-rich. This clearly demonstrates that when utilization is contingent on financing, changes can occur rapidly; and that an integrated approach is required when monitoring equity. From a policy perspective, the Argentine health system appears vulnerable to economic downturns mainly due to high reliance on out-of-pocket payments and the strong link between health insurance and employment. PMID:20452070

  5. Equity during an economic crisis: financing of the Argentine health system.

    PubMed

    Cavagnero, Eleonora; Bilger, Marcel

    2010-07-01

    This article analyses the redistributive effect caused by health financing and the distribution of healthcare utilization in Argentina before and during the severe 2001/2002 economic crisis. Both dramatically changed during this period: the redistributive effect became much more positive and utilization shifted from pro-poor to pro-rich. This clearly demonstrates that when utilization is contingent on financing, changes can occur rapidly; and that an integrated approach is required when monitoring equity. From a policy perspective, the Argentine health system appears vulnerable to economic downturns mainly due to high reliance on out-of-pocket payments and the strong link between health insurance and employment.

  6. Including impacts of particulate emissions on marine ecosystems in life cycle assessment: the case of offshore oil and gas production.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Rye, Henrik; Hertwich, Edgar G

    2011-10-01

    Life cycle assessment is increasingly used to assess the environmental performance of fossil energy systems. Two of the dominant emissions of offshore oil and gas production to the marine environment are the discharge of produced water and drilling waste. Although environmental impacts of produced water are predominantly due to chemical stressors, a major concern regarding drilling waste discharge is the potential physical impact due to particles. At present, impact indicators for particulate emissions are not yet available in life cycle assessment. Here, we develop characterization factors for 2 distinct impacts of particulate emissions: an increased turbidity zone in the water column and physical burial of benthic communities. The characterization factor for turbidity is developed analogous to characterization factors for toxic impacts, and ranges from 1.4 PAF (potentially affected fraction) · m(3) /d/kg(p) (kilogram particulate) to 7.0 x 10³ [corrected] for drilling mud particles discharged from the rig. The characterization factor for burial describes the volume of sediment that is impacted by particle deposition on the seafloor and equals 2.0 × 10(-1) PAF · m(3) /d/kg(p) for cutting particles. This characterization factor is quantified on the basis of initial deposition layer characteristics, such as height and surface area, the initial benthic response, and the recovery rate. We assessed the relevance of including particulate emissions in an impact assessment of offshore oil and gas production. Accordingly, the total impact on the water column and on the sediment was quantified based on emission data of produced water and drilling waste for all oil and gas fields on the Norwegian continental shelf in 2008. Our results show that cutting particles contribute substantially to the total impact of offshore oil and gas production on marine sediments, with a relative contribution of 55% and 31% on the regional and global scale, respectively. In contrast, the

  7. Including impacts of particulate emissions on marine ecosystems in life cycle assessment: the case of offshore oil and gas production.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Rye, Henrik; Hertwich, Edgar G

    2011-10-01

    Life cycle assessment is increasingly used to assess the environmental performance of fossil energy systems. Two of the dominant emissions of offshore oil and gas production to the marine environment are the discharge of produced water and drilling waste. Although environmental impacts of produced water are predominantly due to chemical stressors, a major concern regarding drilling waste discharge is the potential physical impact due to particles. At present, impact indicators for particulate emissions are not yet available in life cycle assessment. Here, we develop characterization factors for 2 distinct impacts of particulate emissions: an increased turbidity zone in the water column and physical burial of benthic communities. The characterization factor for turbidity is developed analogous to characterization factors for toxic impacts, and ranges from 1.4 PAF (potentially affected fraction) · m(3) /d/kg(p) (kilogram particulate) to 7.0 x 10³ [corrected] for drilling mud particles discharged from the rig. The characterization factor for burial describes the volume of sediment that is impacted by particle deposition on the seafloor and equals 2.0 × 10(-1) PAF · m(3) /d/kg(p) for cutting particles. This characterization factor is quantified on the basis of initial deposition layer characteristics, such as height and surface area, the initial benthic response, and the recovery rate. We assessed the relevance of including particulate emissions in an impact assessment of offshore oil and gas production. Accordingly, the total impact on the water column and on the sediment was quantified based on emission data of produced water and drilling waste for all oil and gas fields on the Norwegian continental shelf in 2008. Our results show that cutting particles contribute substantially to the total impact of offshore oil and gas production on marine sediments, with a relative contribution of 55% and 31% on the regional and global scale, respectively. In contrast, the

  8. HYBRID SULFUR CYCLE FLOWSHEETS FOR HYDROGEN PRODUCTION USING HIGH-TEMPERATURE GAS-COOLED REACTORS

    SciTech Connect

    Gorensek, M.

    2011-07-06

    Two hybrid sulfur (HyS) cycle process flowsheets intended for use with high-temperature gas-cooled reactors (HTGRs) are presented. The flowsheets were developed for the Next Generation Nuclear Plant (NGNP) program, and couple a proton exchange membrane (PEM) electrolyzer for the SO2-depolarized electrolysis step with a silicon carbide bayonet reactor for the high-temperature decomposition step. One presumes an HTGR reactor outlet temperature (ROT) of 950 C, the other 750 C. Performance was improved (over earlier flowsheets) by assuming that use of a more acid-tolerant PEM, like acid-doped poly[2,2'-(m-phenylene)-5,5'-bibenzimidazole] (PBI), instead of Nafion{reg_sign}, would allow higher anolyte acid concentrations. Lower ROT was accommodated by adding a direct contact exchange/quench column upstream from the bayonet reactor and dropping the decomposition pressure. Aspen Plus was used to develop material and energy balances. A net thermal efficiency of 44.0% to 47.6%, higher heating value basis is projected for the 950 C case, dropping to 39.9% for the 750 C case.

  9. Life Cycle Assessment of Biogas Production in Small-scale Household Digesters in Vietnam.

    PubMed

    Vu, T K V; Vu, D Q; Jensen, L S; Sommer, S G; Bruun, S

    2015-05-01

    Small-scale household digesters have been promoted across Asia as a sustainable way of handling manure. The major advantages are that they produce biogas and reduce odor. However their disadvantages include the low recycling of nutrients, because digestate is dilute and therefore difficult to transport, and the loss of biogas as a result of cracks and the intentional release of excess biogas. In this study, life cycle assessment (LCA) methodology was used to assess the environmental impacts associated with biogas digesters in Vietnam. Handling 1,000 kg of liquid manure and 100 kg of solid manure in a system with a biogas digester reduced the impact potential from 4.4 kg carbon dioxide (CO2) equivalents to 3.2 kg CO2 equivalents compared with traditional manure management. However, this advantage could easily be compromised if digester construction is considered in the LCA or in situations where there is an excess of biogas which is intentionally released. A sensitivity analysis showed that biogas digesters could be a means of reducing global warming if methane emissions can be kept low. In terms of eutrophication, farms with biogas digesters had 3 to 4 times greater impacts. In order to make biogas digesters sustainable, methods for recycling digestates are urgently required. PMID:25715690

  10. Development, production and life cycle cost assessments for a military transatmospheric vehicle (TAV)

    NASA Astrophysics Data System (ADS)

    Eisman, Mel; Gonzales, Daniel

    1997-01-01

    Transatmospheric Vehicles (TAVs) are envisioned as a new type of reusable launch vehicle (RLV) which could insert themselves or payloads into low earth orbit (LEO) or deliver payloads to distant targets within minutes. Such a vehicle may carry out military, civil, and commercial missions. This paper focuses specifically on two promising military TAV design concepts. Research, development, test and evaluation (RDT&E) costs are estimated for these concepts which include producing both demonstrator and prototype (i.e., X and Y) vehicles during the development phase. A total life cycle cost (LCC) budget forecast is generated for one TAV and for a fleet of six operational military TAVs. The total number of TAV launches provided over the assumed service life of the vehicle fleet are compared to the number provided by an expendable launch vehicle (ELV) for the same total projected budget. The costing methodology used is described along with suggested implementation strategies that could potentially reduce the level of government investment needed for this system acquisition.

  11. Life Cycle Assessment of Biogas Production in Small-scale Household Digesters in Vietnam

    PubMed Central

    Vu, T. K. V.; Vu, D. Q.; Jensen, L. S.; Sommer, S. G.; Bruun, S.

    2015-01-01

    Small-scale household digesters have been promoted across Asia as a sustainable way of handling manure. The major advantages are that they produce biogas and reduce odor. However their disadvantages include the low recycling of nutrients, because digestate is dilute and therefore difficult to transport, and the loss of biogas as a result of cracks and the intentional release of excess biogas. In this study, life cycle assessment (LCA) methodology was used to assess the environmental impacts associated with biogas digesters in Vietnam. Handling 1,000 kg of liquid manure and 100 kg of solid manure in a system with a biogas digester reduced the impact potential from 4.4 kg carbon dioxide (CO2) equivalents to 3.2 kg CO2 equivalents compared with traditional manure management. However, this advantage could easily be compromised if digester construction is considered in the LCA or in situations where there is an excess of biogas which is intentionally released. A sensitivity analysis showed that biogas digesters could be a means of reducing global warming if methane emissions can be kept low. In terms of eutrophication, farms with biogas digesters had 3 to 4 times greater impacts. In order to make biogas digesters sustainable, methods for recycling digestates are urgently required. PMID:25715690

  12. Life Cycle Assessment of Biogas Production in Small-scale Household Digesters in Vietnam.

    PubMed

    Vu, T K V; Vu, D Q; Jensen, L S; Sommer, S G; Bruun, S

    2015-05-01

    Small-scale household digesters have been promoted across Asia as a sustainable way of handling manure. The major advantages are that they produce biogas and reduce odor. However their disadvantages include the low recycling of nutrients, because digestate is dilute and therefore difficult to transport, and the loss of biogas as a result of cracks and the intentional release of excess biogas. In this study, life cycle assessment (LCA) methodology was used to assess the environmental impacts associated with biogas digesters in Vietnam. Handling 1,000 kg of liquid manure and 100 kg of solid manure in a system with a biogas digester reduced the impact potential from 4.4 kg carbon dioxide (CO2) equivalents to 3.2 kg CO2 equivalents compared with traditional manure management. However, this advantage could easily be compromised if digester construction is considered in the LCA or in situations where there is an excess of biogas which is intentionally released. A sensitivity analysis showed that biogas digesters could be a means of reducing global warming if methane emissions can be kept low. In terms of eutrophication, farms with biogas digesters had 3 to 4 times greater impacts. In order to make biogas digesters sustainable, methods for recycling digestates are urgently required.

  13. Life-cycle energy and GHG emissions of forest biomass harvest and transport for biofuel production in Michigan

    SciTech Connect

    Zhang, Fengli; Johnson, Dana M.; Wang, Jinjiang

    2015-04-01

    High dependence on imported oil has increased U.S. strategic vulnerability and prompted more research in the area of renewable energy production. Ethanol production from renewable woody biomass, which could be a substitute for gasoline, has seen increased interest. This study analysed energy use and greenhouse gas emission impacts on the forest biomass supply chain activities within the State of Michigan. A life-cycle assessment of harvesting and transportation stages was completed utilizing peer-reviewed literature. Results for forest-delivered ethanol were compared with those for petroleum gasoline using data specific to the U.S. The analysis from a woody biomass feedstock supply perspective uncovered that ethanol production is more environmentally friendly (about 62% less greenhouse gas emissions) compared with petroleum based fossil fuel production. Sensitivity analysis was conducted with key inputs associated with harvesting and transportation operations. The results showed that research focused on improving biomass recovery efficiency and truck fuel economy further reduced GHG emissions and energy consumption.

  14. Life-cycle energy and GHG emissions of forest biomass harvest and transport for biofuel production in Michigan

    DOE PAGES

    Zhang, Fengli; Johnson, Dana M.; Wang, Jinjiang

    2015-04-01

    High dependence on imported oil has increased U.S. strategic vulnerability and prompted more research in the area of renewable energy production. Ethanol production from renewable woody biomass, which could be a substitute for gasoline, has seen increased interest. This study analysed energy use and greenhouse gas emission impacts on the forest biomass supply chain activities within the State of Michigan. A life-cycle assessment of harvesting and transportation stages was completed utilizing peer-reviewed literature. Results for forest-delivered ethanol were compared with those for petroleum gasoline using data specific to the U.S. The analysis from a woody biomass feedstock supply perspective uncoveredmore » that ethanol production is more environmentally friendly (about 62% less greenhouse gas emissions) compared with petroleum based fossil fuel production. Sensitivity analysis was conducted with key inputs associated with harvesting and transportation operations. The results showed that research focused on improving biomass recovery efficiency and truck fuel economy further reduced GHG emissions and energy consumption.« less

  15. Studies on generalized kinetic model and Pareto optimization of a product-driven self-cycling bioprocess.

    PubMed

    Sun, Kaibiao; Kasperski, Andrzej; Tian, Yuan

    2014-10-01

    The aim of this study is the optimization of a product-driven self-cycling bioprocess and presentation of a way to determine the best possible decision variables out of a set of alternatives based on the designed model. Initially, a product-driven generalized kinetic model, which allows a flexible choice of the most appropriate kinetics is designed and analysed. The optimization problem is given as the bi-objective one, where maximization of biomass productivity and minimization of unproductive loss of substrate are the objective functions. Then, the Pareto fronts are calculated for exemplary kinetics. It is found that in the designed bioprocess, a decrease of emptying/refilling fraction and an increase of substrate feeding concentration cause an increase of the biomass productivity. An increase of emptying/refilling fraction and a decrease of substrate feeding concentration cause a decrease of unproductive loss of substrate. The preferred solutions are calculated using the minimum distance from an ideal solution method, while giving proposals of their modifications derived from a decision maker's reactions to the generated solutions.

  16. Microalgae to biofuels: life cycle impacts of methane production of anaerobically digested lipid extracted algae.

    PubMed

    Quinn, Jason C; Hanif, Asma; Sharvelle, Sybil; Bradley, Thomas H

    2014-11-01

    This study presents experimental measurements of the biochemical methane production for whole and lipid extracted Nannochloropsis salina. Results show whole microalgae produced 430 cm(3)-CH4 g-volatile solids(-1) (g-VS) (σ=60), 3 times more methane than was produced by the LEA, 140 cm(3)-CH4 g-VS(-1) (σ=30). Results illustrate current anaerobic modeling efforts in microalgae to biofuel assessments are not reflecting the impact of lipid removal. On a systems level, the overestimation of methane production is shown to positively skew the environmental impact of the microalgae to biofuels process. Discussion focuses on a comparison results to those of previous anaerobic digestion studies and quantifies the corresponding change in greenhouse gas emissions of the microalgae to biofuels process based on results from this study.

  17. Optimal control of a remanufacturing system with consideration for product life cycle

    NASA Astrophysics Data System (ADS)

    Nakashima, Kenichi; Gupta, Surendra M.

    2004-02-01

    This paper deals with the cost management problem of a remanufacturing system with stochastic variability in the demand rate, the remanufacturing rate and the discard rate. We consider two types of inventories. One is the actual product inventory in the factory while the other is the virtual inventory that is still in use by the consumers. The state of the remanufacturing system is defined by considering the levels of both inventories. The cost function is composed of various costs such as the holding cost, backlogging cost and other manufacturing costs. We obtain the optimal production policy that minimizes the expected average cost per period. Numerical results provide insights on the effects of the various costs on the optimal policy.

  18. Nitrogen cycling through swine production systems: ammonia, dinitrogen, and nitrous oxide emissions.

    PubMed

    Harper, Lowry A; Sharpe, Ron R; Parkin, Tim B; De Visscher, Alex; van Cleemput, Oswald; Byers, F Michael

    2004-01-01

    Ammonia (NH(3)) emissions from animal systems have become a primary concern for all of livestock production. The purpose of this research was to establish the relationship of nitrogen (N) emissions to specific components of swine production systems and to determine accurate NH(3) emission factors appropriate for the regional climate, geography, and production systems. Micrometeorological instrumentation and gas sensors were placed over two lagoons in North Carolina during 1997-1999 to obtain information for determining ammonia emissions over extended periods and without interfering with the surrounding climate. Ammonia emissions varied diurnally and seasonally and were related to lagoon ammonium concentration, acidity, temperature, and wind turbulence. Conversion of significant quantities of ammonium NH(4)(+) to dinitrogen gas (N(2)) were measured in all lagoons with the emission rate largely dependent on NH(4)(+) concentration. Lagoon NH(4)(+) conversion to N(2) accounted for the largest loss component of the N entering the farm (43% as N(2)); however, small amounts of N(2)O were emitted from the lagoon (0.1%) and from field applications (0.05%) when effluent was applied nearby. In disagreement with previous and current estimates of NH(3) emissions from confined animal feeding operation (CAFO) systems, and invalidating current assumptions that most or all emissions are in the form of NH(3), we found much smaller NH(3) emissions from animal housing (7%), lagoons (8%), and fields (2%) using independent measurements of N transformation and transport. Nitrogen input and output in the production system were evaluated, and 95% of input N was accounted for as output N from the system. PMID:15254100

  19. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products, Part 3: LED Environmental Testing

    SciTech Connect

    Tuenge, Jason R.; Hollomon, Brad; Dillon, Heather E.; Snowden-Swan, Lesley J.

    2013-03-01

    This report covers the third part of a larger U.S. Department of Energy (DOE) project to assess the life-cycle environmental and resource impacts in the manufacturing, transport, use, and disposal of light-emitting diode (LED) lighting products in relation to incumbent lighting technologies. All three reports are available on the DOE website (www.ssl.energy.gov/tech_reports.html). • Part 1: Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent and LED Lamps; • Part 2: LED Manufacturing and Performance; • Part 3: LED Environmental Testing. Parts 1 and 2 were published in February and June 2012, respectively. The Part 1 report included a summary of the life-cycle assessment (LCA) process and methodology, provided a literature review of more than 25 existing LCA studies of various lamp types, and performed a meta-analysis comparing LED lamps with incandescent and compact fluorescent lamps (CFLs). Drawing from the Part 1 findings, Part 2 performed a more detailed assessment of the LED manufacturing process and used these findings to provide a comparative LCA taking into consideration a wider range of environmental impacts. Both reports concluded that the life-cycle environmental impact of a given lamp is dominated by the energy used during lamp operation—the upstream generation of electricity drives the total environmental footprint of the product. However, a more detailed understanding of end-of-life disposal considerations for LED products has become increasingly important as their installation base has grown. The Part 3 study (reported herein) was undertaken to augment the LCA findings with chemical analysis of a variety of LED, CFL, and incandescent lamps using standard testing procedures. A total of 22 samples, representing 11 different models, were tested to determine whether any of 17 elements were present at levels exceeding California or Federal regulatory thresholds for hazardous waste. Key findings include: • The selected

  20. Methylmercury cycling in High Arctic wetland ponds: controls on sedimentary production.

    PubMed

    Lehnherr, Igor; St Louis, Vincent L; Kirk, Jane L

    2012-10-01

    Methylmercury (MeHg) is a potent neurotoxin that has been demonstrated to biomagnify in Arctic freshwater foodwebs to levels that may be of concern to Inuit peoples subsisting on freshwater fish, for example. The key process initiating the bioaccumulation and biomagnification of MeHg in foodwebs is the methylation of inorganic Hg(II) to form MeHg, and ultimately how much MeHg enters foodwebs is controlled by the production and availability of MeHg in a particular water body. We used isotopically enriched Hg stable isotope tracers in sediment core incubations to measure potential rates of Hg(II) methylation and investigate the controls on MeHg production in High Arctic wetland ponds in the Lake Hazen region of northern Ellesmere Island (Nunavut, Canada). We show here that MeHg concentrations in sediments are primarily controlled by the sediment methylation potential and the quantity of Hg(II) available for methylation, but not by sediment demethylation potential. Furthermore, MeHg concentrations in pond waters are controlled by MeHg production in sediments, overall anaerobic microbial activity, and photodemethylation in the water column.

  1. Life cycle assessment of milk production from commercial dairy farms: the influence of management tactics.

    PubMed

    Yan, M-J; Humphreys, J; Holden, N M

    2013-07-01

    Little consideration has been given to how farm management, specifically tactics used to implement the management strategy, may influence the carbon footprint (CF) and land use for milk produced on commercial farms. In this study, the CF and land use of milk production from 18 Irish commercial dairy farms were analyzed based on foreground data from a 12-mo survey capturing management tactics and background data from the literature. Large variation was found in farm attributes and management tactics; for example, up to a 1.5-fold difference in fertilizer nitrogen input was used to support the same stocking density, and up to a 3.5-fold difference in concentrate fed for similar milk output per cow. However, the coefficient of variation for milk CF between farms only varied by 13% and for land use by 18%. The overall CF and overall land use of the milk production from the 18 dairy farms was 1.23±0.04kg of CO2 Eq and 1.22±0.05 m(2) per kilogram of energy-corrected milk. Milk output per cow, economic allocation between exports of milk and liveweight, and on-farm diesel use per ha were found to be influential factors on milk CF, whereas the fertilizer N rate, milk output per cow, and economic allocation between exports of milk and liveweight were influential on land use. Effective sward management of white clover within a few farms appeared to lower the CF but increased on-farm land use. It was concluded that a combination of multiple tactics determines CF and land use for milk production on commercial dairy farms and, although these 2 measures of environmental impact are correlated, a farm with a low CF did not always have low land use and vice versa.

  2. Life cycle assessment of milk production from commercial dairy farms: the influence of management tactics.

    PubMed

    Yan, M-J; Humphreys, J; Holden, N M

    2013-07-01

    Little consideration has been given to how farm management, specifically tactics used to implement the management strategy, may influence the carbon footprint (CF) and land use for milk produced on commercial farms. In this study, the CF and land use of milk production from 18 Irish commercial dairy farms were analyzed based on foreground data from a 12-mo survey capturing management tactics and background data from the literature. Large variation was found in farm attributes and management tactics; for example, up to a 1.5-fold difference in fertilizer nitrogen input was used to support the same stocking density, and up to a 3.5-fold difference in concentrate fed for similar milk output per cow. However, the coefficient of variation for milk CF between farms only varied by 13% and for land use by 18%. The overall CF and overall land use of the milk production from the 18 dairy farms was 1.23±0.04kg of CO2 Eq and 1.22±0.05 m(2) per kilogram of energy-corrected milk. Milk output per cow, economic allocation between exports of milk and liveweight, and on-farm diesel use per ha were found to be influential factors on milk CF, whereas the fertilizer N rate, milk output per cow, and economic allocation between exports of milk and liveweight were influential on land use. Effective sward management of white clover within a few farms appeared to lower the CF but increased on-farm land use. It was concluded that a combination of multiple tactics determines CF and land use for milk production on commercial dairy farms and, although these 2 measures of environmental impact are correlated, a farm with a low CF did not always have low land use and vice versa. PMID:23660142

  3. Nuclear-Driven Copper-Based Hybrid Thermo/Electro Chemical Cycle for Hydrogen Production

    SciTech Connect

    Khalil, Yehia F.; Rostkowski, Katherine H.

    2006-07-01

    With a worldwide need for reduction of greenhouse gas emissions, hydrogen gas has become a primary focus of energy researchers as a promising substitute of nonrenewable energy sources. For instance, use of hydrogen gas in fuel cells has received special technological interest particularly from the transportation sector, which is presently dominated by fuel oil. It is not only gaseous hydrogen that is in demand, but the need for liquid hydrogen is growing as well. For example, the aerospace industry uses liquid hydrogen as fuel for space shuttles. The use of liquid hydrogen during a single space shuttle launch requires about 15,000 gallons per minute, which is equivalent to about forty-five hydrogen trailers, each with 13,000 gallons capacity. The hydrogen required to support a single Mars mission would be at least ten times that required for one space shuttle launch. In this work, we provide mass and energy balances, major equipment sizing, and costing of a hybrid CuO-CuSO{sub 4} plant with 1000 MW (30,240 kg/hr) H{sub 2} production capacity. With a 90% annual availability factor, the estimated hydrogen production rate is about 238,412 tons annually, the predicted plant efficiency is about 36%, and the estimated hydrogen production cost is about $4.0/kg (not including storage and transportation costs). In addition to hydrogen production, the proposed plant generates oxygen gas as a byproduct with an estimated flowrate of about 241,920 kg/hr (equivalent to 1,907,297 tons annually). We also propose a novel technology for separating SO{sub 2} and SO{sub 3} from O{sub 2} using a battery of redundant fixed-bed reactors containing CuO impregnated in porous alumina (Al{sub 2}O{sub 3}). This technology accommodates online regeneration of the CuO. Other practical approaches for gaseous separation are also examined including use of ceramic membranes, liquefaction, and regenerable wet scrubbing with slurried magnesium oxide or solutions of sodium salts such as sodium sulfite

  4. Pyrogenic organic matter production from wildfires: a missing sink in the global carbon cycle

    PubMed Central

    Santín, Cristina; Doerr, Stefan H; Preston, Caroline M; González-Rodríguez, Gil

    2015-01-01

    Wildfires release substantial quantities of carbon (C) into the atmosphere but they also convert part of the burnt biomass into pyrogenic organic matter (PyOM). This is richer in C and, overall, more resistant to environmental degradation than the original biomass, and, therefore, PyOM production is an efficient mechanism for C sequestration. The magnitude of this C sink, however, remains poorly quantified, and current production estimates, which suggest that ∽1-5% of the C affected by fire is converted to PyOM, are based on incomplete inventories. Here, we quantify, for the first time, the complete range of PyOM components found in-situ immediately after a typical boreal forest fire. We utilized an experimental high-intensity crown fire in a jack pine forest (Pinus banksiana) and carried out a detailed pre- and postfire inventory and quantification of all fuel components, and the PyOM (i.e., all visually charred, blackened materials) produced in each of them. Our results show that, overall, 27.6% of the C affected by fire was retained in PyOM (4.8 ± 0.8 t C ha−1), rather than emitted to the atmosphere (12.6 ± 4.5 t C ha−1). The conversion rates varied substantially between fuel components. For down wood and bark, over half of the C affected was converted to PyOM, whereas for forest floor it was only one quarter, and less than a tenth for needles. If the overall conversion rate found here were applicable to boreal wildfire in general, it would translate into a PyOM production of ∽100 Tg C yr−1 by wildfire in the global boreal regions, more than five times the amount estimated previously. Our findings suggest that PyOM production from boreal wildfires, and potentially also from other fire-prone ecosystems, may have been underestimated and that its quantitative importance as a C sink warrants its inclusion in the global C budget estimates. PMID:25378275

  5. Pyrogenic organic matter production from wildfires: a missing sink in the global carbon cycle.

    PubMed

    Santín, Cristina; Doerr, Stefan H; Preston, Caroline M; González-Rodríguez, Gil

    2015-04-01

    Wildfires release substantial quantities of carbon (C) into the atmosphere but they also convert part of the burnt biomass into pyrogenic organic matter (PyOM). This is richer in C and, overall, more resistant to environmental degradation than the original biomass, and, therefore, PyOM production is an efficient mechanism for C sequestration. The magnitude of this C sink, however, remains poorly quantified, and current production estimates, which suggest that ~1-5% of the C affected by fire is converted to PyOM, are based on incomplete inventories. Here, we quantify, for the first time, the complete range of PyOM components found in-situ immediately after a typical boreal forest fire. We utilized an experimental high-intensity crown fire in a jack pine forest (Pinus banksiana) and carried out a detailed pre- and postfire inventory and quantification of all fuel components, and the PyOM (i.e., all visually charred, blackened materials) produced in each of them. Our results show that, overall, 27.6% of the C affected by fire was retained in PyOM (4.8 ± 0.8 t C ha(-1)), rather than emitted to the atmosphere (12.6 ± 4.5 t C ha(-1)). The conversion rates varied substantially between fuel components. For down wood and bark, over half of the C affected was converted to PyOM, whereas for forest floor it was only one quarter, and less than a tenth for needles. If the overall conversion rate found here were applicable to boreal wildfire in general, it would translate into a PyOM production of ~100 Tg C yr(-1) by wildfire in the global boreal regions, more than five times the amount estimated previously. Our findings suggest that PyOM production from boreal wildfires, and potentially also from other fire-prone ecosystems, may have been underestimated and that its quantitative importance as a C sink warrants its inclusion in the global C budget estimates. PMID:25378275

  6. Pyrogenic organic matter production from wildfires: a missing sink in the global carbon cycle.

    PubMed

    Santín, Cristina; Doerr, Stefan H; Preston, Caroline M; González-Rodríguez, Gil

    2015-04-01

    Wildfires release substantial quantities of carbon (C) into the atmosphere but they also convert part of the burnt biomass into pyrogenic organic matter (PyOM). This is richer in C and, overall, more resistant to environmental degradation than the original biomass, and, therefore, PyOM production is an efficient mechanism for C sequestration. The magnitude of this C sink, however, remains poorly quantified, and current production estimates, which suggest that ~1-5% of the C affected by fire is converted to PyOM, are based on incomplete inventories. Here, we quantify, for the first time, the complete range of PyOM components found in-situ immediately after a typical boreal forest fire. We utilized an experimental high-intensity crown fire in a jack pine forest (Pinus banksiana) and carried out a detailed pre- and postfire inventory and quantification of all fuel components, and the PyOM (i.e., all visually charred, blackened materials) produced in each of them. Our results show that, overall, 27.6% of the C affected by fire was retained in PyOM (4.8 ± 0.8 t C ha(-1)), rather than emitted to the atmosphere (12.6 ± 4.5 t C ha(-1)). The conversion rates varied substantially between fuel components. For down wood and bark, over half of the C affected was converted to PyOM, whereas for forest floor it was only one quarter, and less than a tenth for needles. If the overall conversion rate found here were applicable to boreal wildfire in general, it would translate into a PyOM production of ~100 Tg C yr(-1) by wildfire in the global boreal regions, more than five times the amount estimated previously. Our findings suggest that PyOM production from boreal wildfires, and potentially also from other fire-prone ecosystems, may have been underestimated and that its quantitative importance as a C sink warrants its inclusion in the global C budget estimates.

  7. Toward Describing the Effects of Ozone Depletion on Marine Primary Productivity and Carbon Cycling

    NASA Technical Reports Server (NTRS)

    Cullen, John J.

    1995-01-01

    This project was aimed at improved predictions of the effects of UVB and ozone depletion on marine primary productivity and carbon flux. A principal objective was to incorporate a new analytical description of photosynthesis as a function of UV and photosynthetically available radiation (Cullen et. al., Science 258:646) into a general oceanographic model. We made significant progress: new insights into the kinetics of photoinhibition were used in the analysis of experiments on Antarctic phytoplankton to generate a general model of UV-induced photoinhibition under the influence of ozone depletion and vertical mixing. The way has been paved for general models on a global scale.

  8. Feedbacks between element availability, (diel) cycling and assimilatory uptake in a biologically productive spring-fed river

    NASA Astrophysics Data System (ADS)

    Kurz, Marie J.; Cohen, Matthew J.; Martin, Jonathan B.; Nifong, Rachel L.

    2016-04-01

    The metabolism of submerged aquatic vegetation directly and indirectly controls the cycling of solutes in streams at diel (24-hour) frequencies. Photosynthesis and respiration induce diel variation in dissolved oxygen (DO) concentrations and pH which, in turn, mediate elemental concentrations via a host of geochemical reactions. Plant metabolism also directly exerts control on water composition via assimilatory uptake, creating diel variation in major nutrients. Trace elements can be essential micronutrients, suggesting their assimilatory uptake could also contribute to diel variation in element concentrations in streams. If diel element variation is indicative of metabolic processing, assessing the magnitude and timing of this diel variation relative to other inorganic controls could be used to estimate the ecosystem demand for those elements, infer ecosystem function, and predict how stream ecosystems may respond to changes in environmental element availability. We evaluated the relationship between the elemental requirements of submerged vegetation and the availability and cycling of elements in streams by comparing spatial and diel variation in stream chemistry with measurements of tissue stoichiometry from submerged vascular plants and algae in the Ichetucknee River (Q = 8 m3/s) , a highly productive spring-fed system in north-central Florida. Diel variations were observed in the concentrations of soluble reactive phosphorus (SRP), Ca, Mg, K, Mn, Fe, V, Cr, Co, Cu, Sr, Ba, and U. Autotrophic assimilation, estimated using the measured stoichiometry and calculations of primary production from diel DO variation, accounted for a significant portion of the in-stream diel variation of some elements, including approximately 100% for K and >30% for Fe and Mn. However, the exact timing of assimilation of these elements remains uncertain relative to the other inorganic controls. Correcting the observed SRP diel signal for the effect of calcite co-precipitation revealed

  9. ENERGY EFFICIENCY LIMITS FOR A RECUPERATIVE BAYONET SULFURIC ACID DECOMPOSITION REACTOR FOR SULFUR CYCLE THERMOCHEMICAL HYDROGEN PRODUCTION

    SciTech Connect

    Gorensek, M.; Edwards, T.

    2009-06-11

    A recuperative bayonet reactor design for the high-temperature sulfuric acid decomposition step in sulfur-based thermochemical hydrogen cycles was evaluated using pinch analysis in conjunction with statistical methods. The objective was to establish the minimum energy requirement. Taking hydrogen production via alkaline electrolysis with nuclear power as the benchmark, the acid decomposition step can consume no more than 450 kJ/mol SO{sub 2} for sulfur cycles to be competitive. The lowest value of the minimum heating target, 320.9 kJ/mol SO{sub 2}, was found at the highest pressure (90 bar) and peak process temperature (900 C) considered, and at a feed concentration of 42.5 mol% H{sub 2}SO{sub 4}. This should be low enough for a practical water-splitting process, even including the additional energy required to concentrate the acid feed. Lower temperatures consistently gave higher minimum heating targets. The lowest peak process temperature that could meet the 450-kJ/mol SO{sub 2} benchmark was 750 C. If the decomposition reactor were to be heated indirectly by an advanced gas-cooled reactor heat source (50 C temperature difference between primary and secondary coolants, 25 C minimum temperature difference between the secondary coolant and the process), then sulfur cycles using this concept could be competitive with alkaline electrolysis provided the primary heat source temperature is at least 825 C. The bayonet design will not be practical if the (primary heat source) reactor outlet temperature is below 825 C.

  10. Implications of incorporating N cycling and N limitations on primary production in an individual-based dynamic vegetation model

    NASA Astrophysics Data System (ADS)

    Smith, B.; Wårlind, D.; Arneth, A.; Hickler, T.; Leadley, P.; Siltberg, J.; Zaehle, S.

    2013-11-01

    The LPJ-GUESS dynamic vegetation model uniquely combines an individual- and patch-based representation of vegetation dynamics with ecosystem biogeochemical cycling from regional to global scales. We present an updated version that includes plant and soil N dynamics, analysing the implications of accounting for C-N interactions on predictions and performance of the model. Stand structural dynamics and allometric scaling of tree growth suggested by global databases of forest stand structure and development were well-reproduced by the model in comparison to an earlier multi-model study. Accounting for N cycle dynamics improved the goodness-of-fit for broadleaved forests. N limitation associated with low N mineralisation rates reduces productivity of cold-climate and dry-climate ecosystems relative to mesic temperate and tropical ecosystems. In a model experiment emulating free-air CO2 enrichment (FACE) treatment for forests globally, N-limitation associated with low N mineralisation rates of colder soils reduces CO2-enhancement of NPP for boreal forests, while some temperate and tropical forests exhibit increased NPP enhancement. Under a business-as-usual future climate and emissions scenario, ecosystem C storage globally was projected to increase by c. 10%; additional N requirements to match this increasing ecosystem C were within the high N supply limit estimated on stoichiometric grounds in an earlier study. Our results highlight the importance of accounting for C-N interactions not only in studies of global terrestrial C cycling, but to understand underlying mechanisms on local scales and in different regional contexts.

  11. Impact of climate change on forests, forest products and the carbon cycle in the Congo Basin.

    NASA Astrophysics Data System (ADS)

    Kruijt, Bart; Jans, Wilma; Franssen, Wietse; Ludwig, Fulco

    2014-05-01

    Africa is widely seen as the continent most vulnerable to climate change. Current climate variability already has a large impact on the economies of developing countries. Large parts of African economies are highly climate sensitive, in particular agriculture, infrastructure and water sector. In this study we performed an analysis of climate change impacts in the Congo Basin on Forest ecosystem functioning and carbon storage. We emphasise the methodologies and validation involved in modelling the basin-wide carbon budgets. We also studied the potential shifts in broad classes of vegetation types, resulting from climate change. Finally, we compared annual productivity of the Congo forests with statistics of wood fuel and charcoal use for each of the countries in the region. The model simulations suggest that the region's forests will see increasing productivity under future climate, however, the effect of rising CO2 concentrations, stimulating growth, is highly uncertain. From these findings it follows that the potential in the region to implement UNFCCC-REDD+ projects is still very uncertain, but probably sustainable and feasible. The analysis shows that, averaged over 10 years, wood fuel and charcoal use amount to 50% and in some countries up to 100% or even more of the yearly vegetation carbon increase. These percentages generally increases with population density.

  12. Boron geochemistry of mud volcano products and their significance for global B cycling

    NASA Astrophysics Data System (ADS)

    Deyhle, A.; Kopf, A.

    2003-04-01

    stress and mobilization depth. Given the abundance and high discharge rates of mud volcanoes along subduction zones, this process generally affects chemical and fluid budgets in the subduction factory. Given the abundance and high discharge rates of mud volcanoes, it clearly has to be considered a major backflux mechanism in global B cycling from the lithosphere to the hydrosphere.

  13. Environmental impacts of organic and conventional agricultural products--are the differences captured by life cycle assessment?

    PubMed

    Meier, Matthias S; Stoessel, Franziska; Jungbluth, Niels; Juraske, Ronnie; Schader, Christian; Stolze, Matthias

    2015-02-01

    Comprehensive assessment tools are needed that reliably describe environmental impacts of different agricultural systems in order to develop sustainable high yielding agricultural production systems with minimal impacts on the environment. Today, Life Cycle Assessment (LCA) is increasingly used to assess and compare the environmental sustainability of agricultural products from conventional and organic agriculture. However, LCA studies comparing agricultural products from conventional and organic farming systems report a wide variation in the resource efficiency of products from these systems. The studies show that impacts per area farmed land are usually less in organic systems, but related to the quantity produced impacts are often higher. We reviewed 34 comparative LCA studies of organic and conventional agricultural products to analyze whether this result is solely due to the usually lower yields in organic systems or also due to inaccurate modeling within LCA. Comparative LCAs on agricultural products from organic and conventional farming systems often do not adequately differentiate the specific characteristics of the respective farming system in the goal and scope definition and in the inventory analysis. Further, often only a limited number of impact categories are assessed within the impact assessment not allowing for a comprehensive environmental assessment. The most critical points we identified relate to the nitrogen (N) fluxes influencing acidification, eutrophication, and global warming potential, and biodiversity. Usually, N-emissions in LCA inventories of agricultural products are based on model calculations. Modeled N-emissions often do not correspond with the actual amount of N left in the system that may result in potential emissions. Reasons for this may be that N-models are not well adapted to the mode of action of organic fertilizers and that N-emission models often are built on assumptions from conventional agriculture leading to even greater

  14. Environmental impacts of organic and conventional agricultural products--are the differences captured by life cycle assessment?

    PubMed

    Meier, Matthias S; Stoessel, Franziska; Jungbluth, Niels; Juraske, Ronnie; Schader, Christian; Stolze, Matthias

    2015-02-01

    Comprehensive assessment tools are needed that reliably describe environmental impacts of different agricultural systems in order to develop sustainable high yielding agricultural production systems with minimal impacts on the environment. Today, Life Cycle Assessment (LCA) is increasingly used to assess and compare the environmental sustainability of agricultural products from conventional and organic agriculture. However, LCA studies comparing agricultural products from conventional and organic farming systems report a wide variation in the resource efficiency of products from these systems. The studies show that impacts per area farmed land are usually less in organic systems, but related to the quantity produced impacts are often higher. We reviewed 34 comparative LCA studies of organic and conventional agricultural products to analyze whether this result is solely due to the usually lower yields in organic systems or also due to inaccurate modeling within LCA. Comparative LCAs on agricultural products from organic and conventional farming systems often do not adequately differentiate the specific characteristics of the respective farming system in the goal and scope definition and in the inventory analysis. Further, often only a limited number of impact categories are assessed within the impact assessment not allowing for a comprehensive environmental assessment. The most critical points we identified relate to the nitrogen (N) fluxes influencing acidification, eutrophication, and global warming potential, and biodiversity. Usually, N-emissions in LCA inventories of agricultural products are based on model calculations. Modeled N-emissions often do not correspond with the actual amount of N left in the system that may result in potential emissions. Reasons for this may be that N-models are not well adapted to the mode of action of organic fertilizers and that N-emission models often are built on assumptions from conventional agriculture leading to even greater

  15. The role of organic ligands in iron cycling and primary productivity in the Antarctic Peninsula: A modeling study

    NASA Astrophysics Data System (ADS)

    Jiang, Mingshun; Barbeau, Katherine A.; Selph, Karen E.; Measures, Christopher I.; Buck, Kristen N.; Azam, Farooq; Greg Mitchell, B.; Zhou, Meng

    2013-06-01

    Iron (Fe) is the limiting nutrient for primary productivity in the Southern Ocean, with much of the dissolved iron (dFe) bound to organic ligands or colloids. A Fe model for the Southern Ocean (SOFe) is developed to understand the role of bacteria and organic ligands in controlling Fe cycling and productivity. The model resolves the classical food web and microbial loop, including three types of nutrients (N, Si, Fe) and two types of Fe ligands. Simulations of the zero-dimensional (0-D) model are calibrated with detailed results of shipboard grow-out incubation experiments conducted with Antarctic Peninsula phytoplankton communities during winter 2006 to provide the best estimate of key biological parameters. Then a one-dimensional (1-D) model is developed by coupling the biological model with the Regional Oceanic Modeling System (ROMS) for a site on the Antarctic Peninsula shelf, and the model parameters are further calibrated with data collected from two surveys (summer 2004 and winter 2006) in the area. The results of the numerical simulations agree reasonably well with observations. An analysis of the 1-D model results suggests that bacteria and organic ligands may play an important role in Fe cycling, which can be categorized into a relatively fast mode within the euphotic zone dominated by photo-reactions (summer d Fe residence time about 600 days) and complexation and a slow mode below with most of the dFe biologically complexed (summer dFe residence time >10 years). The dFe removal from the euphotic zone is dominated by colloidal formation and further aggregations with additional contribution from biological uptake, and an increase of organic ligands would reduce Fe export. The decrease of Fe removal rate over depth is due to the continuous dissolution and remineralization of particulate Fe. A number of sensitivity experiments are carried out for both 0-D and 1-D models to understand the importance of photo-reactive processes in primary productivity

  16. Enhancement of anthraquinone production in Morinda citrifolia cell suspension cultures after stimulation of the proline cycle with two proline analogs.

    PubMed

    Quevedo, Carla V; Perassolo, María; Giulietti, Ana M; Rodríguez Talou, Julián

    2012-03-01

    Synthesis of anthraquinones (AQs) involves the shikimate and 2-C-methyl-D-erythritol 4-phosphate pathways. The proline cycle is linked to the pentose phosphate pathway (PPP) to generate NADPH needed in the first steps of this pathway. The effect of two proline analogs, azetidine-2-carboxylic acid (A2C) and thiazolidine-4-carboxylic acid (T4C), were evaluated in Morinda citrifolia suspension cultures. Both analogs gave higher proline accumulation after 6 and 10 days (68 and 179% after 6 days with A2C at 25 and 50 μM, respectively, and 111% with T4C added at 100 μM). Induction of the proline cycle increased the AQ content after 6 days (~40% for 50 μM A2C and 100 μM T4C). Whereas A2C (50 μM) increased only AQ production, T4C also enhanced total phenolics. However, no induction of the PPP was observed with any of the treatments. This pathway therefore does not limit the supply of carbon skeletons to secondary metabolic pathways.

  17. Improving liquid bait programs for Argentine ant control: bait station density.

    PubMed

    Nelson, Erik H; Daane, Kent M

    2007-12-01

    Argentine ants, Linepithema humile (Mayr), have a positive effect on populations of mealybugs (Pseudococcus spp.) in California vineyards. Previous studies have shown reductions in both ant activity and mealybug numbers after liquid ant baits were deployed in vineyards at densities of 85-620 bait stations/ha. However, bait station densities may need to be <85 bait stations/ha before bait-based strategies for ant control are economically comparable to spray-based insecticide treatments-a condition that, if met, will encourage the commercial adoption of liquid baits for ant control. This research assessed the effectiveness of baits deployed at lower densities. Two field experiments were conducted in commercial vineyards. In experiment 1, baits were deployed at 54-225 bait stations/ha in 2005 and 2006. In experiment 2, baits were deployed at 34-205 bait stations/ha in 2006 only. In both experiments, ant activity and the density of mealybugs in grape fruit clusters at harvest time declined with increasing bait station density. In 2005 only, European fruit lecanium scale [Parthenolecanium corni (Bouché)] were also present in fruit clusters, and scale densities were negatively related to bait station density. The results indicate that the amount of ant and mealybug control achieved by an incremental increase in the number of bait stations per hectare is constant across a broad range of bait station densities. The results are discussed in the context of commercializing liquid ant baits to provide a more sustainable Argentine ant control strategy.

  18. Laboratory and Field Evaluations of Polyacrylamide Hydrogel Baits Against Argentine Ants (Hymenoptera: Formicidae).

    PubMed

    Rust, Michael K; Soeprono, Andrew; Wright, Sarajean; Greenberg, Les; Choe, Dong-Hwan; Boser, Christina L; Cory, Coleen; Hanna, Cause

    2015-06-01

    The development of effective baits to control the Argentine ant, Linepithema humile (Mayr), has been problematic because foragers prefer sweet liquids, while many toxicants are insoluble in water and liquid baits are generally difficult to deliver. The incorporation of thiamethoxam and sucrose solutions into a water-absorbing polyacrylamide hydrogel provides a unique and novel carrier and method of application for liquid baits. Formulations of thiamethoxam affected the size of the hydrogels, and sucrose solutions containing 0.0003% technical thiamethoxam provided hydrogels as large as those made with 25% sucrose solution or deionized water. Concentrations of thiamethoxam as low as 0.000075% in the hydrogels provided 50% kill of workers within 3 d in a laboratory setting. In small colony studies, baiting with 0.00015 and 0.000075% thiamethoxam hydrogels provided 100% mortality of workers and queens within 8 d. An enzyme-linked immunosorbent assay indicated that thiamethoxam was absorbed into the interior of the polyacrylamide matrix. The water loss rates of the hydrogels were dependent upon the relative humidity. Polyacrylamide hydrogels with >50% water loss were less attractive to ants. Field studies in highly infested areas indicated that concentrations of 0.0006 or 0.0018% thiamethoxam were more effective than 0.00015%. Hydrogels may provide a cost-effective alternative to providing aqueous baits to control Argentine ants. PMID:26470250

  19. Potential application of Northern Argentine propolis to control some phytopathogenic bacteria.

    PubMed

    Ordóñez, R M; Zampini, I C; Moreno, M I Nieva; Isla, M I

    2011-10-20

    The antimicrobial activity of samples of Northern Argentine propolis (Tucumán, Santiago del Estero and Chaco) against phytopathogenic bacteria was assessed and the most active samples were identified. Minimal inhibitory concentration (MIC) values were determined by agar macrodilution and broth microdilution assays. Strong antibacterial activity was detected against Erwinia carotovora spp carotovora CECT 225, Pseudomonas syringae pvar tomato CECT 126, Pseudomonas corrugata CECT 124 and Xanthomonas campestris pvar vesicatoria CECT 792. The most active propolis extract (Tucumán, T1) was selected to bioguide isolation and identified for antimicrobial compound (2',4'-dihydroxychalcone). The antibacterial chalcone was more active than the propolis ethanolic extract (MIC values of 0.5-1 μg ml(-1) and 9.5-15 μg ml(-1), respectively). Phytotoxicity assays were realized and the propolis extracts did not retard germination of lettuce seeds or the growth of onion roots. Propolis solutions applied as sprays on tomato fruits infected with P. syringae reduced the severity of disease. Application of the Argentine propolis extracts diluted with water may be promising for the management of post harvest diseases of fruits.

  20. Potential application of Northern Argentine propolis to control some phytopathogenic bacteria.

    PubMed

    Ordóñez, R M; Zampini, I C; Moreno, M I Nieva; Isla, M I

    2011-10-20

    The antimicrobial activity of samples of Northern Argentine propolis (Tucumán, Santiago del Estero and Chaco) against phytopathogenic bacteria was assessed and the most active samples were identified. Minimal inhibitory concentration (MIC) values were determined by agar macrodilution and broth microdilution assays. Strong antibacterial activity was detected against Erwinia carotovora spp carotovora CECT 225, Pseudomonas syringae pvar tomato CECT 126, Pseudomonas corrugata CECT 124 and Xanthomonas campestris pvar vesicatoria CECT 792. The most active propolis extract (Tucumán, T1) was selected to bioguide isolation and identified for antimicrobial compound (2',4'-dihydroxychalcone). The antibacterial chalcone was more active than the propolis ethanolic extract (MIC values of 0.5-1 μg ml(-1) and 9.5-15 μg ml(-1), respectively). Phytotoxicity assays were realized and the propolis extracts did not retard germination of lettuce seeds or the growth of onion roots. Propolis solutions applied as sprays on tomato fruits infected with P. syringae reduced the severity of disease. Application of the Argentine propolis extracts diluted with water may be promising for the management of post harvest diseases of fruits. PMID:21237629

  1. Viral strain dependent differences in experimental Argentine hemorrhagic fever (Junin virus) infection of guinea pigs.

    PubMed

    Kenyon, R H; Green, D E; Maiztegui, J I; Peters, C J

    1988-01-01

    Guinea pigs infected with low-passage Junin virus of human origin showed viral strain dependent differences in mortality, LD50, time to death, and in viral spread and distribution. Different Junin strains appeared to cause at least two broad patterns of Argentine hemorrhagic fever in guinea pigs. A number of strains of Junin virus caused a viscerotropic type of illness in which virus replicated predominantly in lymph nodes, spleen, and bone marrow. With the most severe visceral forms of Argentine hemorrhagic fever, the guinea pigs became viremic, developed necrosis of spleen, lymph nodes, and bone marrow, showed gastric hemorrhages, and all animals died within 13-15 days. Other Junin strains induced a neurological type of illness with transient viral replication in and lymphocyte depletion of spleen and lymph nodes, with no detectable viremia or viral replication in bone marrow. Subsequently, virus was found in the brain with varying severities of polioencephalitis, and the guinea pigs frequently showed rear leg paralysis before death occurred 28-34 days after inoculation. Not all animals infected with a neurotropic strain developed all these signs. One viral strain induced some signs characteristic of both patterns of illness. Although the disease forms in the guinea pig model did not strictly correlate with those observed in the humans from which these strains were obtained, the different strains of Junin virus consistently caused very different patterns of illness in infected guinea pigs.

  2. Laboratory and Field Evaluations of Polyacrylamide Hydrogel Baits Against Argentine Ants (Hymenoptera: Formicidae).

    PubMed

    Rust, Michael K; Soeprono, Andrew; Wright, Sarajean; Greenberg, Les; Choe, Dong-Hwan; Boser, Christina L; Cory, Coleen; Hanna, Cause

    2015-06-01

    The development of effective baits to control the Argentine ant, Linepithema humile (Mayr), has been problematic because foragers prefer sweet liquids, while many toxicants are insoluble in water and liquid baits are generally difficult to deliver. The incorporation of thiamethoxam and sucrose solutions into a water-absorbing polyacrylamide hydrogel provides a unique and novel carrier and method of application for liquid baits. Formulations of thiamethoxam affected the size of the hydrogels, and sucrose solutions containing 0.0003% technical thiamethoxam provided hydrogels as large as those made with 25% sucrose solution or deionized water. Concentrations of thiamethoxam as low as 0.000075% in the hydrogels provided 50% kill of workers within 3 d in a laboratory setting. In small colony studies, baiting with 0.00015 and 0.000075% thiamethoxam hydrogels provided 100% mortality of workers and queens within 8 d. An enzyme-linked immunosorbent assay indicated that thiamethoxam was absorbed into the interior of the polyacrylamide matrix. The water loss rates of the hydrogels were dependent upon the relative humidity. Polyacrylamide hydrogels with >50% water loss were less attractive to ants. Field studies in highly infested areas indicated that concentrations of 0.0006 or 0.0018% thiamethoxam were more effective than 0.00015%. Hydrogels may provide a cost-effective alternative to providing aqueous baits to control Argentine ants.

  3. Development of virtual bait stations to control Argentine ants (Hymenoptera: Formicidae) in environmentally sensitive habitats.

    PubMed

    Choe, Dong-Hwan; Vetter, Richard S; Rust, Michael K

    2010-10-01

    A novel bait station referred to as a virtual bait station was developed and tested against field populations of the invasive Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), at White Beach, Camp Pendleton, in Oceanside, CA. White Beach is a nesting habitat for an endangered seabird, the California least tern (Sterna antillarum browni Mearns). The beach is heavily infested with Argentine ants, one of the threats for the California least tern chicks. Conventional pest control strategies are prohibited because of the existence of the protected bird species and the site's proximity to the ocean. The bait station consisted of a polyvinyl chloride pipe that was treated on the inside with fipronil insecticide at low concentrations to obtain delayed toxicity against ants. The pipe was provisioned with an inverted bottle of 25% sucrose solution, then capped, and buried in the sand. Foraging ants crossed the treated surface to consume the sucrose solution. The delayed toxicity of fipronil deposits allowed the ants to continue foraging on the sucrose solution and to interact with their nestmates, killing them within 3-5 d after exposure. Further modification of the bait station design minimized the accumulation of dead ants in the sucrose solution, significantly improving the longevity and efficacy of the bait station. The virtual bait station exploits the foraging behavior of the ants and provides a low impact approach to control ants in environmentally sensitive habitats. It excluded all insects except ants, required only milligram quantities of toxicant, and eliminated the problem of formulating toxicants into aqueous sugar baits.

  4. Nutrition and interference competition have interactive effects on the behavior and performance of Argentine ants.

    PubMed

    Kay, Adam D; Zumbusch, Taylor; Heinen, Justa L; Marsh, Tom C; Holway, David A

    2010-01-01

    Food availability often influences competitive outcomes through effects on consumer growth. Although it has received less attention, food availability may also affect competition through nutritional effects on behavior. One hypothesis linking nutrition and competition in ants posits that increased access to carbohydrates favors greater investment in worker traits that underlie behavioral dominance. We tested this hypothesis by varying dietary protein:carbohydrate (P:C) ratios and levels of interspecific interference for Argentine ants (Linepithema humile), a widespread invasive species. As predicted, colonies facing interference increased patrolling more when reared on low P:C diets; this result is the first demonstration of an interactive effect of nutrition and interference on ant colonies. Several results suggest that this dietary effect on patrolling was due primarily to changes in colony size rather than worker behavior. Colonies on lower P:C diets had lower worker mortality and larger final colony sizes. Diet had little effect on per capita patrolling, and worker behavior in performance assays depended more on previous exposure to interference than on diet. Our findings indicate that dietary P:C ratios can influence Argentine ant performance in a competitive environment and suggest a mechanism by which monopolization of carbohydrate-rich resources can help invasive ants displace native ant competitors.

  5. Quantitative analysis of the effects of the exotic Argentine ant on seed-dispersal mutualisms

    PubMed Central

    Rodriguez-Cabal, Mariano A.; Stuble, Katharine L.; Nuñez, Martin A.; Sanders, Nathan J.

    2009-01-01

    Although it is increasingly clear that exotic invasive species affect seed-dispersal mutualisms, a synthetic examination of the effect of exotic invasive species on seed-dispersal mutualisms is lacking. Here, we review the impacts of the invasive Argentine ant (Linepithema humile) on seed dispersal. We found that sites with L. humile had 92 per cent fewer native ant seed dispersers than did sites where L. humile was absent. In addition, L. humile did not replace native seed dispersers, as rates of seed removal and seedling establishment were all lower in the presence of L. humile than in its absence. We conclude that potential shifts in plant diversity and concomitant changes in ecosystem function may be a consequence of Argentine ant invasions, as well as invasions by other ant species. Because very few studies have examined the effects of non-ant invasive species on seed-dispersal mutualisms, the prevalence of disruption of seed-dispersal mutualisms by invasive species is unclear. PMID:19465575

  6. Carbon monitoring of tree encroachment in Argentine savanna

    NASA Astrophysics Data System (ADS)

    Gonzalez-Roglich, M.; Swenson, J. J.

    2013-12-01

    Land cover change dynamics alter ecosystem and climate functioning primarily through changes in matter cycles and energy fluxes. Woody plant encroachment in semiarid rangelands is a widespread process of land cover change driven by a combination of local land use practices and global environmental changes. Increases in woody plant cover alter the distribution of carbon and can affect water and nutrient s in the ecosystem. Rangelands comprise almost 45% of the global land surface, yet our understanding of the effects of woody plant encroachment is limited, in most cases, to fine resolution studies of the northern hemisphere. In this study we analyzed the consequences of woody plant encroachment on ecosystem carbon stocks at a regional scale (30,000 km2) across the transitional zone of the Western Pampas grasslands and the Caldenal Savannas of Argentina. A space-for-time substitution approach was used to analyze changes in C stocks in the woody plant, grass, litter and soil organic carbon pools along an encroachment gradient. We found a significant increase in ecosystem C stocks along the encroachment gradient, with mean values of 4.5, 8.4, 12.4, and 16.5 kgC/m2 for grasslands, shrublands, open and closed forests respectively. As in most semiarid systems, soil organic C is the single largest pool in the ecosystem, containing between 63 and 71% of the total C (1.5 m depth). Woody plant percent cover and soil texture (i.e. percent silt content), where the two primary factors accounting for the variability of C in the ecosystem, together explaining 81.0% and 84.7% of the variability in soil organic C and total ecosystem C stocks, respectively. This is the first study that assess the effect of woody plant encroachment at a regional scale in the Southern Hemisphere, finding important gains in ecosystem C stocks with the increase in woody plants cover. The very simple models presented here are a very valuable tool for rapid field assessment, and if combined with remotely

  7. Online purchasing creates opportunities to lower the life cycle carbon footprints of consumer products.

    PubMed

    Isley, Steven C; Stern, Paul C; Carmichael, Scott P; Joseph, Karun M; Arent, Douglas J

    2016-08-30

    A major barrier to transitions to environmental sustainability is that consumers lack information about the full environmental footprints of their purchases. Sellers' incentives do not support reducing the footprints unless customers have such information and are willing to act on it. We explore the potential of modern information technology to lower this barrier by enabling firms to inform customers of products' environmental footprints at the point of purchase and easily offset consumers' contributions through bundled purchases of carbon offsets. Using online stated choice experiments, we evaluated the effectiveness of several inexpensive features that firms in four industries could implement with existing online user interfaces for consumers. These examples illustrate the potential for firms to lower their overall carbon footprints while improving customer satisfaction by lowering the "soft costs" to consumers of proenvironmental choices. Opportunities such as these likely exist wherever firms possess environmentally relevant data not accessible to consumers or when transaction costs make proenvironmental action difficult.

  8. Online purchasing creates opportunities to lower the life cycle carbon footprints of consumer products.

    PubMed

    Isley, Steven C; Stern, Paul C; Carmichael, Scott P; Joseph, Karun M; Arent, Douglas J

    2016-08-30

    A major barrier to transitions to environmental sustainability is that consumers lack information about the full environmental footprints of their purchases. Sellers' incentives do not support reducing the footprints unless customers have such information and are willing to act on it. We explore the potential of modern information technology to lower this barrier by enabling firms to inform customers of products' environmental footprints at the point of purchase and easily offset consumers' contributions through bundled purchases of carbon offsets. Using online stated choice experiments, we evaluated the effectiveness of several inexpensive features that firms in four industries could implement with existing online user interfaces for consumers. These examples illustrate the potential for firms to lower their overall carbon footprints while improving customer satisfaction by lowering the "soft costs" to consumers of proenvironmental choices. Opportunities such as these likely exist wherever firms possess environmentally relevant data not accessible to consumers or when transaction costs make proenvironmental action difficult. PMID:27528670

  9. Life cycle assessment of a palm oil system with simultaneous production of biodiesel and cooking oil in Cameroon.

    PubMed

    Achten, Wouter M J; Vandenbempt, Pieter; Almeida, Joana; Mathijs, Erik; Muys, Bart

    2010-06-15

    The use of palm oil as a biofuel has been heavily debated for its land-use conflict with nature and its competition with food production, being the number one cooking oil worldwide. In that context, we present a life cycle assessment of a palm oil production process yielding both biodiesel and cooking oil, incorporating the land-use impact and evaluating the effect of treating the palm oil mill effluent (POME) prior to disposal. The results show that the nonrenewable energy requirement, global warming potential (GWP; exclusive land-use change), and acidification potential are lower than those of the fossil alternative. However, the system triggers an increase in eutrophication potential (EP) compared to the fossil fuel reference. This system shows less energy requirement, global warming and acidification reduction, and less eutrophication increase compared to the reference than the same system converting all palm oil into biodiesel (no cooking oil production). The land occupation of palm oil triggers ecosystem quality (EQ) loss of 30-45% compared to the potential natural vegetation. Furthermore, such land-use change triggers a carbon debt neutralizing the GWP reduction for 45-53 years. The POME treatment scenarios reveal a trade-off between GWP and EP. PMID:20496929

  10. Mercury cycling in