990 resultados para Red edge emission


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Ihmisen toiminnan vaikutus ilmakehään johtaa todennäköisesti ilmastonmuutoksiin. Eräs näistä muutoksista on maapallon keskilämpötilan nousu, joka aiheutuu kasvihuonekaasujen lisääntyneestä pitoisuudesta ilmakehässä. Vaikutusten vähentämiseksi on hiilidioksidipäästöjä vähennettävä. Kioton pöytäkirja asettaa allekirjoittaneille maille päästövelvoitteet. Euroopan unionin tulee vähentää kasvihuonekaasupäästöjään 8%:lla. Eräs vähennysmekanismeista on päästökauppa. Päästökauppa on sekä keino suojella ympäristöä että ympäristöpoliittinen instrumentti kasvihuonekaasupäästövähennysten kustannusten keventämiseksi. Päästökauppa ei suoranaisesti vähennä kasvihuonekaasupäästöjä, vaan tasaa niitä maiden ja laitosten välillä. Uusiutuvan energian käytön edistäminen sekä kansainvälisesti että kansallisesti johtaa suoriin kasvihuonekaasupäästöjen vähenemiseen. Euroopan unionin jäsenvaltiot ovat asettaneet kansalliset viitearvot uusituvan sähkön kulutukselle. Saavuttaakseen nämä viitearvot maiden tulee tukea uusiutuvia energialähteitä eri menetelmin kuten vihreillä sertifikaateilla. Päästökauppa ja kaupattavat vihreät sertifikaatit tulevat vaikuttamaan energiantuottajien liiketoimintaan. Työssä on tutkittu päästökaupan ja vihreiden sertifikaattien vaikutuksia Vattenfall Kaukolämpö Oy:n, Vattenfall Sähköntuotanto Oy:n ja Vamy Oy:n liiketoimintaan.

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We show that the quasifission paths predicted by the one-body dissipation dynamics, in the slowest phase of a binary reaction, follow a quasistatic path, which represents a sequence of states of thermal equilibrium at a fixed value of the deformation coordinate. This establishes the use of the statistical particle-evaporation model in the case of dynamical time-evolving systems. Pre- and post-scission multiplicities of neutrons and total multiplicities of protons and α particles in fission reactions of 63Cu+92Mo, 60Ni+100Mo, 63Cu+100Mo at 10 MeV/u and 20Ne+144,148,154Sm at 20 MeV/u are reproduced reasonably well with statistical model calculations performed along dynamic trajectories whose slow stage (from the most compact configuration up to the point where the neck starts to develop) lasts some 35×10−21 s.

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Tässä diplomityössä tavoitteena on selvittää käytännöt ja menetelmät, joilla UPM-Kymmenen sellu-, paperi- ja vaneritehtaat ympäri maailman mittaavat ja laskevat ilmapäästönsä. Tämä tehdään kyselylomakkeella, joka lähetetään tehtaiden ympäristöpäälliköille. Kaikki tärkeimmät seikat ilmapäästöihin liittyen, kuten vaaditut jatkuvatoimiset mittaukset, jaksottaiset mittaukset, raportointikäytäntö, kalibrointi jne. kysytään lomakkeessa. Kyselylomakkeessa painotetaan mittauskäytäntöä sellutehtaissa sekä energiantuotannossa. Saatujen tulosten perusteella annetaan ehdotuksia sekä ohjeita tulevaisuutta varten, jotta mittaustulosten kokoaminen helpottuisi ja vertailukelpoisuus paranisi. Työn kirjallisuusosuudessa selvitetään yleisimmät päästölähteet sekä päästökomponentit paperi –ja selluteollisuudessa. Näiden ei toivottujen yhdisteiden syntymekanismit sekä menetelmät niiden poistamiseksi savukaasuista on myös lyhyesti kuvailtu. Myös erilaiset analysointi- ja näytteenottomenetelmät on kerrottu. Erot tehtaiden ympäristöluvissa käydään läpi, jakaen tehtaat kolmeen maantieteelliseen ryhmään. Lupakäytäntöjen osalta Suomen osuutta on painotettu, sillä UPM-Kymmene on varsin Suomikeskeinen yhtiö tehtaiden lukumääriin ja sijainteihin katsottuna. Viranomaismääräykset sekä päästörajat muutamista tehtaista on esitetty havainnollistaakseen alueellisia eroja.

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The age of erythrocyte concentrates (EC) in transfusion medicine and the adverse outcomes when transfusing long-term-stored EC are highly controversial issues. Whereas the definition of a short-term-stored EC or a long-term-stored EC is unclear in clinical trials, data based on in vitro storage assays can help defining a limit in addition of the expiration date. The present review merges together these data in order to highlight an EC age cut-off and points out potential misleading consideration. The analysis of in vitro data highlights the presence of reversible and irreversible storage lesions and demonstrates that red blood cells (RBC) exhibit two limits during storage: one around 2 weeks and another one around 4 weeks of storage. Of particular importance, the first lesions to appear, i.e. the reversible ones, are per se reversible once transfused, whereas the irreversible lesions are not. In clinical trials, the EC age cut-off for short-term storage is in general fewer than 14 days (11 ± 4 days) and more disperse for long-term-stored EC (17 ± 13 days), regardless the clinical outcomes. Taking together, EC age cut-off in clinical trials does not totally fall into line of in vitro aging data, whereas it is the key criteria in clinical studies. Long-term-stored EC considered in clinical trials are not probably old enough to answer the question: "Does transfusion of long-term-stored EC (older than 4 weeks) result in worse clinical outcomes?" Depending on ethical concerns and clinical practices, older EC than currently assayed in clinical trials should have to be considered. These two worlds trying to understand the aging of erythrocytes and the impact on patients do not seem to speak the same language.

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The appearance of the Banco de Barcelona involved the formation of an investment compact network between its directors. In this work we studied how this investment network grew within a larger one, the one formed by the major investors in Catalonia during the period 1815-1866, as well as the role played by the top executives of the Bank inside it. Our findings indicate that some of the directors of the Bank held a central position in the main Catalan investors" network. This important role guaranteed reliable information on the progress of businesses. This information not only favored the operations of the institution, but also allowed its directors to take investment decisions inside the network. Moreover, the Bank interconnects individuals who were associated with different investors" sectors, which made the institution coalesced around an investing core with different important influences and connections.

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Background: Hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR) gene mutation have been postulated as a possible cause of recurrent miscarriage (RM). There is a wide variation in the prevalence of MTHFR polymorphisms and homocysteine (Hcy) plasma levels among populations around the world. The present study was undertaken to investigate the possible association between hyperhomocysteinemia and its causative genetic or acquired factors and RM in Catalonia, a Mediterranean region in Spain. Methods: Sixty consecutive patients with ≥ 3 unexplained RM and 30 healthy control women having at least one child but no previous miscarriage were included. Plasma Hcy levels, MTHFR gene mutation, red blood cell (RBC) folate and vitamin B12 serum levels were measured in all subjects. Results: No significant differences were observed neither in plasma Hcy levels, RBC folate and vitamin B12 serum levels nor in the prevalence of homozygous and heterozygous MTHFR gene mutation between the two groups studied. Conclusions: In the present study RM is not associated with hyperhomocysteinemia, and/or the MTHFR gene mutation.

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Tämän diplomityön tavoitteena oli löytää prosessiparametrejä nestepakkauskartongin reuna-alueiden kuivatuskutistuman hallintaan ja saada tuotteen reuna-alueiden sileystaso paremmaksi. Tarkoituksena oli parantaa reuna-alueiden painettavuusominaisuuksia sekä saada koneen poikkisuunnassa laadultaan parempi tuote. Työn kirjallisuusosassa on tarkasteltu työn kannalta nestepakkauskartongin kriittisimpiä ominaisuuksia, sileyttä ja jäykkyyttä. Lisäksi kirjallisuusosassa on tarkasteltu kuitujen ominaisuuksia, sylinterikuivatusta ja kuivatuskutistumaa. Kokeellisessa osassa on etsitty esitutkimuksella prosessiparametrejä, jotka ovat aiheuttaneet poikkisuunnan sileyserojen kasvun kartonkikoneen investoinnin jälkeen. Suoria korrelaatioita prosessiparametrien ja kuivatuskutistuman välille ei löydetty. Kokeellisen osan tehdasmittakaavaisissa koeajoissa tutkittiin kahdeksan eri parametrin vaikutusta kuivatuskutistumaan, jotka perustuivat kirjallisuuteen. Tutkituista parametreistä huulisuihkun iskukulman muutoksella sekä konesuuntaisella kuivatusprofiililla ei ollut vaikutusta kuivatuskutistumaan. Runkokerroksen mäntysellun korvaaminen koivusellulla vähensi kuivatuskutistumaa ja lisäsi sileyttä, mutta tuotteen palstautumislujuus ei tällöin ollut riittävä. Retentiokemikaalien reseptimuutoksilla pinta- ja taustakerroksen välillä, kuivatusosan nollatason laskulla ja perälaatikkosakeuksien pienentämisellä oli vähän vaikutusta kuivatuskutistumaan. Vaikutus reuna-alueiden sileyteen oli kuitenkin vähemmän kuin 10 %. Diplomityön perusteella kuivatusosan nopeuseroilla ja kuivatusviirojen kireyksillä oli suurin vaikutusta kuivatuskutistumaan ja reuna-alueiden sileystasoon. Lisäämällä nopeuseroja ja kiristämällä kuivatusviiroja reuna-alueiden sileyttä pystyttiin parantamaan yli 20 %.

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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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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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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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A disseminação de Xanthomonas campestris pv. viticola (Xcv), agente do cancro bacteriano da videira, ocorre, dentre outras formas, por meio de mudas e bacelos infectados. Foi estudada a obtenção de material propagativo livre do patógeno, testando a eficiência do tratamento de bacelos com termoterapia, bactericidas e sanitizantes. Os isolados de Xcv foram testados quanto à patogenicidade e realizado o teste de sensibilidade in vitro aos produtos, em diferentes concentrações. A erradicação de Xcv em bacelos de videira foi testada em experimentos com termoterapia (50ºC por 30 e 40 min; 53ºC por 5 e 10 min); bactericidas [oxitetraciclina+sulfato de cobre (150+2.000; 165+2.200; 180+2.400 e 195+2.600 mg L-1 de H2O) e oxitetraciclina (600; 700; 800 e 900 mg L-1)]; e sanitizantes [cloreto de dodecildimetil amônio (600; 1.200; 1.800; 2.400 e 3.000 µL L-1); hipoclorito de sódio (5.000; 10.000; 20.000; 30.000 e 40.000 µL L-1) e cloreto de benzalcônio (125; 167;250; 334 e 500 µL L-1)]. Foram avaliados período de incubação, incidência e severidade da doença. O bactericida oxitetraciclina e os sanitizantes cloreto de dodecildimetil amônio e hipoclorito de sódio proporcionaram os maiores halos de inibição de Xcv in vitro. No entanto, apesar dos diversos tratamentos testados, não foi possível recomendar tratamento termoterápico ou produto que erradicasse Xcv de bacelos infectados. Porém, ficou confirmada a grande importância destes na disseminação do agente do cancro bacteriano da videira.

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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.