960 resultados para Emission trade


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The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 1012 electron volts and are bright sources of very-high-energy (VHE) γ-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE γ-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.

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We explore the possible association between the microquasar LSI +61°303 and the EGRET source 2CG 135+01/3EG J0241+6103 by studying, with a detailed numerical model, whether this system can produce the emission and the variability detected by EGRET (>100 MeV) through inverse Compton (IC) scattering. Our numerical approach considers a population of relativistic electrons entrained in a cylindrical inhomogeneous jet, interacting with both the radiation and the magnetic fields, taking into account the Thomson and Klein-Nishina regimes of interaction. Our results reproduce the observed spectral characteristics and variability at γ-rays, thus strengthening the identification of LSI +61°303 as a high-energy γ-ray source.

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Ants are among the most problematic invasive species. They displace numerous native species, alter ecosystem processes, and can have negative impacts on agriculture and human health. In part, their success might stem from a departure from the discovery-dominance trade-off that can promote co-existence in native ant communities, that is, invasive ants are thought to be at the same time behaviorally dominant and faster discoverers of resources, compared to native species. However, it has not yet been tested whether similar asymmetries in behavioral dominance, exploration, and recruitment abilities also exist among invasive species. Here, we establish a dominance hierarchy among four of the most problematic invasive ants (Linepithema humile, Lasius neglectus, Wasmannia auropunctata, Pheidole megacephala) that may be able to arrive and establish in the same areas in the future. To assess behavioral dominance, we used confrontation experiments, testing the aggressiveness in individual and group interactions between all species pairs. In addition, to compare discovery efficiency, we tested the species' capacity to locate a food resource in a maze, and the capacity to recruit nestmates to exploit a food resource. The four species differed greatly in their capacity to discover resources and to recruit nestmates and to dominate the other species. Our results are consistent with a discovery-dominance trade-off. The species that showed the highest level of interspecific aggressiveness and dominance during dyadic interactions.

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The concentration and ratio of terpenoids in the headspace volatile blend of plants have a fundamental role in the communication of plants and insects. The sesquiterpene (E)-nerolidol is one of the important volatiles with effect on beneficial carnivores for biologic pest management in the field. To optimize de novo biosynthesis and reliable and uniform emission of (E)-nerolidol, we engineered different steps of the (E)-nerolidol biosynthesis pathway in Arabidopsis thaliana. Introduction of a mitochondrial nerolidol synthase gene mediates de novo emission of (E)-nerolidol and linalool. Co-expression of the mitochondrial FPS1 and cytosolic HMGR1 increased the number of emitting transgenic plants (incidence rate) and the emission rate of both volatiles. No association between the emission rate of transgenic volatiles and their growth inhibitory effect could be established. (E)-Nerolidol was to a large extent metabolized to non-volatile conjugates.

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[spa] Para hacer frente a los riesgos relacionados con la contaminación atmosférica, es ampliamente aceptada la necesidad de instrumentos de política encaminados a reducir las emisiones. La intervención tiene por objeto reducir las conductas contaminantes y incentivar una conducta más respetuosa y el uso de tecnologías más eficientes. La Unión Europea cuenta con dos importantes mecanismos económicos para el control de emisiones a escala europea: la directiva sobre los impuestos energéticos, un instrumento de fiscalidad ambiental aprobado en 2003 que afecta el precio de los productos energéticos, y el sistema de comercio de los derechos de emisiones, introducido en 2005, que afecta directamente a la cantidad de emisiones de CO2. En 2011, la Comisión Europea propuso una nueva versión de la directiva sobre los impuestos energéticos. El objetivo principal de la propuesta es aumentar la eficacia del instrumento a través de una mayor presión fiscal sobre los productos energéticos y de coordinar este instrumento de fiscalidad medioambiental con el sistema de comercio de los derechos de emisiones, para establecer una señal de precio de CO2 coherente para todos los sectores. Sin embargo, en mayo de 2012 el Parlamento Europeo bloqueó la propuesta de la nueva versión del impuesto, y el proceso de actualización se detuvo. La preocupación principal parecía ser el efecto de dicha propuesta en la competitividad, en particular para los sectores que serían los más afectados dado el uso intensivo de los productos energéticos, como el sector del transporte. El objetivo de este estudio es analizar el efecto que la reforma de la directiva sobre los impuestos energéticos podría tener sobre el nivel de precios, en particular en los países de la Unión Europea donde esta reforma implicaría un aumento de los impuestos energéticos. Utilizando datos del proyecto “World Input-Output Database”, la principal conclusión es que el nuevo sistema de impuestos energéticos tendría un impacto muy bajo sobre los precios. Por lo tanto, dado que los precios no serían fuertemente afectados por la reforma, no habrá inconvenientes para la competitividad y implicaciones en términos de distribución, pero, por otro lado, este resultado también implica una baja capacidad de esta reforma para provocar cambios en el consumo y la producción hacia menos presiones ambientales.

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[spa] Para hacer frente a los riesgos relacionados con la contaminación atmosférica, es ampliamente aceptada la necesidad de instrumentos de política encaminados a reducir las emisiones. La intervención tiene por objeto reducir las conductas contaminantes y incentivar una conducta más respetuosa y el uso de tecnologías más eficientes. La Unión Europea cuenta con dos importantes mecanismos económicos para el control de emisiones a escala europea: la directiva sobre los impuestos energéticos, un instrumento de fiscalidad ambiental aprobado en 2003 que afecta el precio de los productos energéticos, y el sistema de comercio de los derechos de emisiones, introducido en 2005, que afecta directamente a la cantidad de emisiones de CO2. En 2011, la Comisión Europea propuso una nueva versión de la directiva sobre los impuestos energéticos. El objetivo principal de la propuesta es aumentar la eficacia del instrumento a través de una mayor presión fiscal sobre los productos energéticos y de coordinar este instrumento de fiscalidad medioambiental con el sistema de comercio de los derechos de emisiones, para establecer una señal de precio de CO2 coherente para todos los sectores. Sin embargo, en mayo de 2012 el Parlamento Europeo bloqueó la propuesta de la nueva versión del impuesto, y el proceso de actualización se detuvo. La preocupación principal parecía ser el efecto de dicha propuesta en la competitividad, en particular para los sectores que serían los más afectados dado el uso intensivo de los productos energéticos, como el sector del transporte. El objetivo de este estudio es analizar el efecto que la reforma de la directiva sobre los impuestos energéticos podría tener sobre el nivel de precios, en particular en los países de la Unión Europea donde esta reforma implicaría un aumento de los impuestos energéticos. Utilizando datos del proyecto “World Input-Output Database”, la principal conclusión es que el nuevo sistema de impuestos energéticos tendría un impacto muy bajo sobre los precios. Por lo tanto, dado que los precios no serían fuertemente afectados por la reforma, no habrá inconvenientes para la competitividad y implicaciones en términos de distribución, pero, por otro lado, este resultado también implica una baja capacidad de esta reforma para provocar cambios en el consumo y la producción hacia menos presiones ambientales.

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Dissolved organic matter (DOM) is a complex mixture of organic compounds, ubiquitous in marine and freshwater systems. Fluorescence spectroscopy, by means of Excitation-Emission Matrices (EEM), has become an indispensable tool to study DOM sources, transport and fate in aquatic ecosystems. However the statistical treatment of large and heterogeneous EEM data sets still represents an important challenge for biogeochemists. Recently, Self-Organising Maps (SOM) has been proposed as a tool to explore patterns in large EEM data sets. SOM is a pattern recognition method which clusterizes and reduces the dimensionality of input EEMs without relying on any assumption about the data structure. In this paper, we show how SOM, coupled with a correlation analysis of the component planes, can be used both to explore patterns among samples, as well as to identify individual fluorescence components. We analysed a large and heterogeneous EEM data set, including samples from a river catchment collected under a range of hydrological conditions, along a 60-km downstream gradient, and under the influence of different degrees of anthropogenic impact. According to our results, chemical industry effluents appeared to have unique and distinctive spectral characteristics. On the other hand, river samples collected under flash flood conditions showed homogeneous EEM shapes. The correlation analysis of the component planes suggested the presence of four fluorescence components, consistent with DOM components previously described in the literature. A remarkable strength of this methodology was that outlier samples appeared naturally integrated in the analysis. We conclude that SOM coupled with a correlation analysis procedure is a promising tool for studying large and heterogeneous EEM data sets.

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Työn päätavoite on tutkia vihreän sähkön ja sertifikaattien kaupan ja EY:n uusien ilmastonmuutosta koskevien direktiivien ja direktiiviehdotusten välisiä yhteyksiä. Tutkimuksessa käsitellään direktiiviä sähköntuotannosta uusiutuvilla energialähteillä ja direktiiviehdotuksia Euroopan Unionin alueen päästökaupasta sekä yhdistetyn sähkön ja lämmön tuotannon lisäämisestä. Työ keskittyy erään suomalaisen metsäteollisuusyrityksen toimiin ilmastonmuutoksen hidastamiseksi. Tutkimus keskittyy pääosin EU:n suunnitelmaan aloittaa Unionin jäsenvaltioiden välinen päästökauppa, koska tämä järjestelmä tulee toteutuessaan olemaan teollisuuden kannalta merkittävä. Tilannetta on analysoitu neljän sellu- ja paperitehtaan hiilidioksidipäästölaskelmien avulla. Työssä kehitettyjä laskumalleja voidaan käyttää avuksi yhtiön muilla tehtailla. Tämän lisäksi työssä on luotu malli energiainvestointien arvioimiseksi tulevaisuudessa ottamalla päästöoikeuden hinnan vaikutus huomioon. Päästökaupan vaikutukset pohjoismaisilla vapautuneilla sähkömarkkinoilla on analysoity, koska teollinen sähkönhankinta on suuresti riippuvainen tästä markkinasta. Suomen metsäteollisuuden oma yhdistetty sähkön ja lämmön tuotanto erityisesti uusiutuvista energialähteistä tulee olemaan entistäkin tärkeämpää tiukentuvassa toimintaympäristössä. Tällä hetkellä on käynnissä kokeilu lisäarvon saamiseksi omalle sähköntuotannolle. Tällä haetaan kokemuksia ja valmiutta tulevaa päästökauppaa varten.

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Tämän tutkintotyön tavoitteena on selvittää operatiivista ostotoimintaa, joka sisältää oikea-aikaisen tilausrytmin ja tasapainoisen tilausmäärän määrityksen sekä saapuvan tavaravirran mukauttamisen myyntiin tai kulutukseen kokonaisuutena. Tässä tutkimuksessa tarkastellaan myös varastojen merkitystä ja ostotoiminnan kannalta keskeisimpiä tehokkaaseen varastonohjaukseen liittyviä tunnuslukuja. Tutkimus sisältää lääkkeiden toimitusketjun kuvauksen, koska se poikkeaa merkittävästi muista toimialoista. Tämä tutkintotyö on syntetisoiva kirjallisuustutkimus. Tutkintotyön empiirisessä osassa analysoidaan aluksi case-yrityksen vaihto-omaisuusvaraston ohjausta ostotoiminnan näkökulmasta ABC analyysiin pohjautuen. Tämän jälkeen ostotoimintaa analysoidaan tarkemmin tiettyjen toimittajien osalta. Lopuksi laaditaan optimaalinen tilausrytmi ja tilausmäärät sekä ostobudjetti yhden toimittajan tuotteille. ABC analyysia voidaan hyödyntää työkaluna määriteltäessä miten erilaisten tuotteiden materiaalivirtoja tulisi ostotoiminnan kannalta ohjata. Analyysi perustuu resurssien keskittämiseen sinne missä tuotto on suurin.

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This thesis was made in Naantali plant of Finnfeeds Finland Oy. In this thesis the main study was in reducing, controlling, measuring and processing odour effluents in various methods. Also are considered legislation, marketing issues and environmental requirements of reducing of odour effluents. The literature review introduces odours complications, legislations and various methods of odour removal. There is also a review of volatile organic compounds detection and measuring methods. The experimental section consists TD-GC-MS-measurements and expansive measurements with electronic nose. Electronic nose is a new solution for recognition and measuring industrial odours. In this thesis the electronic nose was adapted into reliable recognition and measuring method. Measurements with electronic nose was made in betaine factory and main targets were odour removal process and other odours from factory. As a result of experimental work with TD-GC-MS-measurements becomes odour compound of 2-and 3- methylbutanal and dimethyldisulfide, which odour is sweet and fug. Extensive study with electronic nose found many developmental subjects. Odour balance measurements of factory and after calculation made adjustment of odour removal process, over all odour effluent to environment will reduce 25 %.

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Context.Massive stars form in dense and massive molecular cores. The exact formation mechanism is unclear, but it is possible that some massive stars are formed by processes similar to those that produce the low-mass stars, with accretion/ejection phenomena occurring at some point of the evolution of the protostar. This picture seems to be supported by the detection of a collimated stellar wind emanating from the massive protostar IRAS 16547-4247. A triple radio source is associated with the protostar: a compact core and two radio lobes. The emission of the southern lobe is clearly non-thermal. Such emission is interpreted as synchrotron radiation produced by relativistic electrons locally accelerated at the termination point of a thermal jet. Since the ambient medium is determined by the properties of the molecular cloud in which the whole system is embedded, we can expect high densities of particles and infrared photons. Because of the confirmed presence of relativistic electrons, inverse Compton and relativistic Bremsstrahlung interactions are unavoidable. Aims.We aim to make quantitative predictions of the spectral energy distribution of the non-thermal spots generated by massive young stellar objects, with emphasis on the particular case of IRAS 16547-4247. Methods.We study the high-energy emission generated by the relativistic electrons which produce the non-thermal radio source in IRAS 16547-4247. We also study the result of proton acceleration at the terminal shock of the thermal jet and make estimates of the secondary gamma rays and electron-positron pairs produced by pion decay. Results.We present spectral energy distributions for the southern lobe of IRAS 16547-4247, for a variety of conditions. We show that high-energy emission might be detectable from this object in the gamma-ray domain. The source may also be detectable in X-rays through long exposures with current X-ray instruments. Conclusions.Gamma-ray telescopes such as GLAST, and even ground-based Cherenkov arrays of new generation can be used to study non-thermal processes occurring during the formation of massive stars.

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The animal gut plays a central role in tackling two common ecological challenges, nutrient shortage and food-borne parasites, the former by efficient digestion and nutrient absorption, the latter by acting as an immune organ and a barrier. It remains unknown whether these functions can be independently optimised by evolution, or whether they interfere with each other. We report that Drosophila melanogaster populations adapted during 160 generations of experimental evolution to chronic larval malnutrition became more susceptible to intestinal infection with the opportunistic bacterial pathogen Pseudomonas entomophila. However, they do not show suppressed immune response or higher bacterial loads. Rather, their increased susceptibility to P. entomophila is largely mediated by an elevated predisposition to loss of intestinal barrier integrity upon infection. These results may reflect a trade-off between the efficiency of nutrient extraction from poor food and the protective function of the gut, in particular its tolerance to pathogen-induced damage.

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The classical theory of collision induced emission (CIE) from pairs of dissimilar rare gas atoms was developed in Paper I [D. Reguera and G. Birnbaum, J. Chem. Phys. 125, 184304 (2006)] from a knowledge of the straight line collision trajectory and the assumption that the magnitude of the dipole could be represented by an exponential function of the inter-nuclear distance. This theory is extended here to deal with other functional forms of the induced dipole as revealed by ab initio calculations. Accurate analytical expression for the CIE can be obtained by least square fitting of the ab initio values of the dipole as a function of inter-atomic separation using a sum of exponentials and then proceeding as in Paper I. However, we also show how the multi-exponential fit can be replaced by a simpler fit using only two analytic functions. Our analysis is applied to the polar molecules HF and HBr. Unlike the rare gas atoms considered previously, these atomic pairs form stable bound diatomic molecules. We show that, interestingly, the spectra of these reactive molecules are characterized by the presence of multiple peaks. We also discuss the CIE arising from half collisions in excited electronic states, which in principle could be probed in photo-dissociation experiments.

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O Breast Imaging Reporting and Data System (BI-RADS™), do American College of hRadiology, foi concebido para padronizar o laudo mamográfico e reduzir os fatores de confusão na descrição e interpretação das imagens, além de facilitar o monitoramento do resultado final. OBJETIVO: Identificar a maneira como vem sendo utilizado o BI-RADS™, gerando informações que possam auxiliar o Colégio Brasileiro de Radiologia a desenvolver estratégias para aperfeiçoar o seu uso. MATERIAIS E MÉTODOS: Os dados foram coletados na cidade de Goiânia, GO. Foram solicitados os exames de mamografia anteriores a todas as mulheres que se dirigiram ao serviço para realização de mamografia entre janeiro/2003 e junho/2003. Foram incluídos na análise exames anteriores, realizados entre 1/7/2001 e 30/6/2003. RESULTADOS: Foram coletados 104 laudos anteriores, emitidos por 40 radiologistas de 33 diferentes serviços. Dos 104 laudos, 77% (n = 80) utilizavam o BI-RADS™. Destes, apenas 15% (n = 12) eram concisos, nenhum utilizava a estrutura e organização recomendadas pelo sistema, 98,75% (n = 79) não respeitavam o léxico e 65% (n = 51) não faziam recomendação de conduta. CONCLUSÃO: O BI-RADS™, apesar de bastante utilizado, não foi reconhecido como sistema para padronização dos laudos. Foi usado quase exclusivamente como forma de classificação final dos exames.