955 resultados para bio-stimulant


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Asphalt binder is typically modified with poly type (styrene-butadiene-styrene or SBS) polymers to improve its rheological properties and performance grade. The elastic and principal component of SBS polymers is butadiene. For the last decade, butadiene prices have fluctuated and significantly increased, leading state highway agencies to search for economically viable alternatives to butadiene based materials. This project reports the recent advances in polymerization techniques that have enabled the synthesis of elastomeric, thermoplastic, block-copolymers (BCPs) comprised of styrene and soybean oil, where the “B” block in SBS polymers is replaced with polymerized triglycerides derived from soybean oil. These new breeds of biopolymers have elastomeric properties comparable to well-established butadiene-based styrenic BCPs. In this report, two types of biopolymer formulations are evaluated for their ability to modify asphalt binder. Laboratory blends of asphalt modified with the biopolymers are tested for their rheological properties and performance grade. Blends of asphalt modified with the biopolymers are compared to blends of asphalt modified with two commonly used commercial polymers. The viscoelastic properties of the blends show that biopolymers improve the performance grade of the asphalt to a similar and even greater extent as the commercial SBS polymers. Results shown in this report indicate there is an excellent potential for the future of these biopolymers as economically and environmentally favorable alternatives to their petrochemically-derived analogs.

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The bio-economic model "Heures" is a first attempt to develop a simulation procedure to understand the Northwestern Mediterranean fisheries, to evaluate management strategies and to analyze the feasibility of implementing an adaptative management. The model is built on the interaction among three boxes simulating the dynamics of each of the basic actors of a fishery: the stock, the market and the fishermen. A fourth actor, the manager, imposes or modifies the rules, or, in terms of the model, modifies some particular parameters. Thus, the model allows us to simulate and evaluate the mid-term biologic and economic effects of particular management measures. The bio-economic nature of the model is given by the interaction among the three boxes, by the market simulation and, particularly, by the fishermen behaviour. This last element confers to the model its Mediterranean"selfregulated" character. The fishermen allocate their investments to maximize fishing mortality but, having a legal effort limit, they invest in maintenance and technology in order to increase the catchability, which, as a consequence. will be function of the invested capital.

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Vuoden 2004 väittelijän palkinnon saajan puhe VII Oikeuskulttuurin päivässä 11.11.2005

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The Iowa economy is undergoing great change. Among the sectors deemed important to Iowa’s economic future is bioscience. Definition of what constitutes the bioscience sector but suggests it includes agricultural, medical, plant-life sciences, and related industrial activity.

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Crops and forests are already responding to rising atmospheric carbon dioxide and air temperatures. Increasing atmospheric CO2 concentrations are expected to enhance plant photosynthesis. Nevertheless, after long-term exposure, plants acclimate and show a reduction in photosynthetic activity (i.e. down-regulation). If in the future the Earth"s temperature is allowed to rise further, plant ecosystems and food security will both face significant threats. The scientific community has recognized that an increase in global temperatures should remain below 2°C in order to combat climate change. All this evidence suggests that, in parallel with reductions in CO2 emissions, a more direct approach to mitigate global warming should be considered. We propose here that global warming could be partially mitigated directly through local bio-geoengineering approaches. For example, this could be done through the management of solar radiation at surface level, i.e. by increasing global albedo. Such an effect has been documented in the south-eastern part of Spain, where a significant surface air temperature trend of -0.3°C per decade has been observed due to a dramatic expansion of greenhouse horticulture.

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Background: The reduction in the amount of food available for European avian scavengers as a consequence of restrictive public health policies is a concern for managers and conservationists. Since 2002, the application of several sanitary regulations has limited the availability of feeding resources provided by domestic carcasses, but theoretical studies assessing whether the availability of food resources provided by wild ungulates are enough to cover energetic requirements are lacking. Methodology/Findings: We assessed food provided by a wild ungulate population in two areas of NE Spain inhabited by three vulture species and developed a P System computational model to assess the effects of the carrion resources provided on their population dynamics. We compared the real population trend with to a hypothetical scenario in which only food provided by wild ungulates was available. Simulation testing of the model suggests that wild ungulates constitute an important food resource in the Pyrenees and the vulture population inhabiting this area could grow if only the food provided by wild ungulates would be available. On the contrary, in the Pre-Pyrenees there is insufficient food to cover the energy requirements of avian scavenger guilds, declining sharply if biomass from domestic animals would not be available. Conclusions/Significance: Our results suggest that public health legislation can modify scavenger population trends if a large number of domestic ungulate carcasses disappear from the mountains. In this case, food provided by wild ungulates could be not enough and supplementary feeding could be necessary if other alternative food resources are not available (i.e. the reintroduction of wild ungulates), preferably in European Mediterranean scenarios sharing similar and socio-economic conditions where there are low densities of wild ungulates. Managers should anticipate the conservation actions required by assessing food availability and the possible scenarios in order to make the most suitable decisions.

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O objetivo deste trabalho foi avaliar a conservação pós-colheita de manga 'Tommy Atkins' orgânica destinada à exportação, colhida com Boas Práticas Agrícolas (CBP) e sem Boas Práticas Agrícolas (SBP), sob recobrimentos bio-orgânicos. Manga colhida na maturidade comercial foi recoberta com extrato de erva-doce a 1,5% (CBP+ED, SBP+ED), com extrato de erva-doce adicionada à fécula de mandioca a 3,0% (CBP+ED+F, SBP+ED+F) e Controle (sem recobrimento, CBP e SBP), armazenada a 10±0,5 ºC e 85±2% UR. O uso de BPA manteve a qualidade. O recobrimento com ED comprometeu a aparência da manga pela incidência de manchas na casca; recobrimento associando F + ED manteve a qualidade e retardou o amadurecimento.

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Tutkimuksen tarkoituksena oli tuottaa tietoa kuiva-, bio-, hyöty- ja ongelmajätteiden keskitetysti kilpailutetun kuljetusjärjestelmän eduista ja haitoista Etelä-Karjalan Jätehuolto Oy:n alueella. Tutkimuksessa esitellään jätteenkuljetusjärjestelmien ominaisuudet ja niiden suunnittelu sekä jätehuoltoa ja jätteenkuljetuksia koskeva lainsäädäntö. Keskitetysti kilpailutettu jätteenkuljetusjärjestelmä mitoitettiin järjestelmän nykytilan kuvauksen sekä muualla Suomessa kilpailutuksesta saatujen kokemusten avulla. Järjestelmää arvioitiin vertaamalla kaluston tarvetta, kuormapainoja sekä kuljetuskustannuksia nykyiseen tilanteeseen. Lopuksi arvioitiin jatkokehitystarpeita ja tarvittavia toimenpiteitä, kun keskitettyyn kilpailuttamiseen siirrytään. Jätteenkuljetusten keskitetyllä kilpailuttamisella voidaan saavuttaa etuja nykyiseen kuntakohtaiseen jätteenkuljetukseen verrattuna. Edut syntyvät kun päällekkäiset ajot sekä siirtoajot vähenevät ja kuormakoot kasvavat. Kuljetukset voidaan hoitaa pienemmällä kalustomäärällä, jolloin myös kuljetuskustannukset laskevat.

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Se estudian los Moluscos, Foraminíferos, Palinología, Nanoplancton calcáreo de unos nuevos niveles arcilloso-limosos descubiertos en la excavación de un pozo en las proximidades de la Ermita de Berà (Tarragona); la excelente conservación de los restos paleontológicos permite un estudio más exahustivo. En conjunto, la mayoría de las características indican que se trataría de una sedimentación en condiciones neríticas alrededor de los 30 metros de profundidad con ciertas influencias de carácter estuarino. La presencia de abundantes Orbulina, T. mayeri, junto con G. praemenardii y ausencia de G. fohsi peripheroronda (presente en otras secciones próximas) permite atribuir los niveles a la biozona de G. mayeri, de edad Serravalliense; los datos de Nanoplancton son acordes con dicha edad.

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Crops and forests are already responding to rising atmospheric carbon dioxide and air temperatures. Increasing atmospheric CO2 concentrations are expected to enhance plant photosynthesis. Nevertheless, after long-term exposure, plants acclimate and show a reduction in photosynthetic activity (i.e. down-regulation). If in the future the Earth"s temperature is allowed to rise further, plant ecosystems and food security will both face significant threats. The scientific community has recognized that an increase in global temperatures should remain below 2°C in order to combat climate change. All this evidence suggests that, in parallel with reductions in CO2 emissions, a more direct approach to mitigate global warming should be considered. We propose here that global warming could be partially mitigated directly through local bio-geoengineering approaches. For example, this could be done through the management of solar radiation at surface level, i.e. by increasing global albedo. Such an effect has been documented in the south-eastern part of Spain, where a significant surface air temperature trend of -0.3°C per decade has been observed due to a dramatic expansion of greenhouse horticulture.