990 resultados para Ton
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Volatile organic compounds (VOCs) released by soil microorganisms influence plant growth and pathogen resistance. Yet, very little is known about their influence on herbivores and higher trophic levels. We studied the origin and role of a major bacterial VOC, 2,3-butanediol (2,3-BD), on plant growth, pathogen and herbivore resistance, and the attraction of natural enemies in maize. One of the major contributors to 2,3-BD in the headspace of soil-grown maize seedlings was identified as Enterobacter aerogenes, an endophytic bacterium that colonizes the plants. The production of 2,3-BD by E. aerogenes rendered maize plants more resistant against the Northern corn leaf blight fungus Setosphaeria turcica. On the contrary, E. aerogenes-inoculated plants were less resistant against the caterpillar Spodoptera littoralis. The effect of 2,3-BD on the attraction of the parasitoid Cotesia marginiventris was more variable: 2,3-BD application to the headspace of the plants had no effect on the parasitoids, but application to the soil increased parasitoid attraction. Furthermore, inoculation of seeds with E. aerogenes decreased plant attractiveness, whereas inoculation of soil with a total extract of soil microbes increased parasitoid attraction, suggesting that the effect of 2,3-BD on the parasitoid is indirect and depends on the composition of the microbial community.
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Welsch (Projektbearbeiter): In konziliantem Ton vorgetragener, in der Sache jedoch intransigenter Katalog von Forderungen nach der Niederschlagung der italienischen Nationalbewegung im Königreich Lombardei-Venetien: Verbleib des Territoriums bei Österreich, Ergebenheitsadresse einer noch zu bildenden Deputation aus Vertretern aller italienischen Staaten in Wien, Reduzierung des Anteils an ethnischen Italienern in austroitalienischen Truppenteilen auf mindestens 50% und Verlegung besagter Truppenteile in nichtitalienischsprachige Landesteile Österreichs, Einführung eines obligatorischen deutschen Sprachunterrichts in Lombardei-Venetien sowie einer 20%-Quotenregelung für Nichtitaliener bei Beamtenstellen. Einzige Zugeständnisse: Aufnahme von Vertretern aus dem Trentino in die o.a. Deputation, dreimonatige Residenzpflicht des Kaisers in Lombardei-Venetien, Zulassung der italienischen Sprache im Reichstag
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Benzoxazinoids (BXs), such as 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA), are secondary metabolites in grasses. The first step in BX biosynthesis converts indole-3-glycerol phosphate into indole. In maize (Zea mays), this reaction is catalyzed by either BENZOXAZINELESS1 (BX1) or INDOLE GLYCEROL PHOSPHATE LYASE (IGL). The Bx1 gene is under developmental control and is mainly responsible for BX production, whereas the Igl gene is inducible by stress signals, such as wounding, herbivory, or jasmonates. To determine the role of BXs in defense against aphids and fungi, we compared basal resistance between Bx1 wild-type and bx1 mutant lines in the igl mutant background, thereby preventing BX production from IGL. Compared to Bx1 wild-type plants, BX-deficient bx1 mutant plants allowed better development of the cereal aphid Rhopalosiphum padi, and were affected in penetration resistance against the fungus Setosphaeria turtica. At stages preceding major tissue disruption, R. padi and S. turtica elicited increased accumulation of DIMBOA-glucoside, DIMBOA, and 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one-glucoside (HDMBOA-glc), which was most pronounced in apoplastic leaf extracts. Treatment with the defense elicitor chitosan similarly enhanced apoplastic accumulation of DIMBOA and HDMBOA-glc, but repressed transcription of genes controlling BX biosynthesis downstream of BX1. This repression was also obtained after treatment with the BX precursor indole and DIMBOA, but not with HDMBOA-glc. Furthermore, BX-deficient bx1 mutant lines deposited less chitosan-induced callose than Bx1 wild-type lines, whereas apoplast infiltration with DIMBOA, but not HDMBOA-glc, mimicked chitosan-induced callose. Hence, DIMBOA functions as a defense regulatory signal in maize innate immunity, which acts in addition to its well-characterized activity as a biocidal defense metabolite.
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Plants activate local and systemic defence mechanisms upon exposure to stress. This innate immune response is partially regulated by plant hormones, and involves the accumulation of defensive metabolites. Although local defence reactions to herbivores are well studied, less is known about the impact of root herbivory on shoot defence. Here, we examined the effects of belowground infestation by the western corn rootworm Diabrotica virgifera virgifera on aboveground resistance in maize. Belowground herbivory by D. v. virgifera induced aboveground resistance against the generalist herbivore Spodoptera littoralis, and the necrotrophic pathogen Setosphaeria turcica. Furthermore, D. v. virgifera increased shoot levels of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), and primed the induction of chlorogenic acid upon subsequent infestation by S. littoralis. To gain insight into the signalling network behind this below- and aboveground defence interaction, we compiled a set of 32 defence-related genes, which can be used as transcriptional marker systems to detect activities of different hormone-response pathways. Belowground attack by D. v. virgifera triggered an ABA-inducible transcription pattern in the shoot. The quantification of defence hormones showed a local increase in the production of oxylipins after root and shoot infestation by D. v. virgifera and S. littoralis, respectively. On the other hand, ABA accumulated locally and systemically upon belowground attack by D. v. virgifera. Furthermore, D. v. virgifera reduced the aboveground water content, whereas the removal of similar quantities of root biomass had no effect. Our study shows that root herbivory by D. v. virgifera specifically alters the aboveground defence status of a maize, and suggests that ABA plays a role in the signalling network mediating this interaction.
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Plants are important mediators between above- and belowground herbivores. Consequently, interactions between root and shoot defences can have far-reaching impacts on entire food webs. We recently reported that infestation of maize roots by the root feeding larvae of the beetle Diabrotica virgifera virgifera boosts shoot resistance against herbivores and pathogens. Root herbivory also induced DIMBOA levels and primed for enhanced induction of chlorogenic acid, two secondary metabolites that have been associated with biotic stress resistance. Interestingly, ABA emerged as a putative long-distance signal, possibly responsible for this effect. In this addendum, we investigate the role of root-derived ABA in the systemic regulation of aboveground DIMBOA, and the phenolic compounds chlorogenic acid, caffeic and ferulic acid. We discuss the relevance of the plant hormone in relation to defence against the leaf herbivore Spodoptera littoralis. Soil-drench treatment with ABA mimicked root herbivore-induced accumulation of DIMBOA in the leaves. Similarly, ABA mimicked aboveground priming of chlorogenic acid production, resulting in augmented accumulation of this compound upon subsequent shoot attack by S. littoralis. These findings confirm our notion that ABA acts as an important signal in the regulation of aboveground defence upon belowground herbivory. However, based on our previous finding that ABA alone is not sufficient to trigger aboveground resistance against S. littoralis caterpillars, the results suggest that the ABA-inducible effects on DIMBOA and chlorogenic acid are not solely responsible for root herbivore-induced resistance against S. littoralis. Full text HTML PDF
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We present a barium (Ba) isotope fractionation study of marine biogenic carbonates (aragonitic corals). The major aim is to provide first constraints on the Ba isotope fractionation between modern surface sea water and coral skele- ton. Mediterranean surface sea water was found to be enriched in the heavy Ba isotopes compared to previously reported values for marine open ocean authi- genic and terrestrial minerals. In aquarium experiments with a continuous sup- ply of Mediterranean surface water, the Ba isotopic composition of the bulk sample originating from cultured, aragonitic scleractinian corals (d137/134Ba between +0.16 +/- 0.12permil and +0.41 +/-0.12permil) were isotopically identical or lighter than that of the ambient Mediterranean surface sea water (d137/134Ba = +0.42 +/- 0.07permil, 2SD), which corresponds to an empirical maximum value of Ba isotope fractionation of D137/134Bacoral-seawater = -0.26 +/- 0.14permil at 25°C. This maximum Ba isotope fractionation is close and identical in direction to previous results from inorganic precipitation experiments with aragonite- structured pure BaCO3 (witherite). The variability in measured Ba concentrations of the cultured corals is at odds with a uniform distribution coefficient, DBa/Ca, thus indicating stronger vital effects on isotope than element discrimination. This observation supports the hypothesis that the Ba isotopic compositions of these corals do not result from simple equilibrium between the skeleton and the bulk sea water. Complementary coral samples from natural settings (tropical shallow-water corals from the Bahamas and Florida and cold- water corals from the Norwegian continental shelf) show an even wider range in d137/134Ba values (+0.14 +/- 0.08permil and +0.77 +/- 0.11permil), most probably due to additional spatial and/or temporal sea water heterogeneity, as indicated by recent publications.
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BACKGROUND Historically, percutaneous coronary intervention (PCI) of bifurcation lesions was associated with worse procedural and clinical outcomes when compared with PCI of non-bifurcation lesions. Newer generation drug-eluting stents (DES) might improve long-term clinical outcomes after bifurcation PCI. METHODS AND RESULTS The LEADERS trial was a 10-center, assessor-blind, non-inferiority, all-comers trial, randomizing 1,707 patients to treatment with a biolimus A9(TM) -eluting stent (BES) with an abluminal biodegradable polymer or a sirolimus-eluting stent (SES) with a durable polymer (ClinicalTrials.gov Identifier: NCT00389220). Five-year clinical outcomes were compared between patients with and without bifurcation lesions and between BES and SES in the bifurcation lesion subgroup. There were 497 (29%) patients with at least 1 bifurcation lesion (BES = 258; SES = 239). At 5-year follow-up, the composite endpoint of cardiac death, myocardial infarction (MI) and clinically-indicated (CI) target vessel revascularization (TVR) was observed more frequently in the bifurcation group (26.6% vs. 22.4%, P = 0.049). Within the bifurcation lesion subgroup, no differences were observed in (cardiac) death or MI rates between BES and SES. However, CI target lesion revascularization (TLR) (10.1% vs. 15.9%, P = 0.0495), and CI TVR (12.0% vs. 19.2%, P = 0.023) rates were significantly lower in the BES group. Definite/probable stent thrombosis (ST) rate was numerically lower in the BES group (3.1% vs. 5.9%, P = 0.15). Very late (>1 year) definite/probable ST rates trended to be lower with BES (0.4% vs. 3.1%, P = 0.057). CONCLUSIONS In the treatment of bifurcation lesions, use of BES led to superior long-term efficacy compared with SES. Safety outcomes were comparable between BES and SES, with an observed trend toward a lower rate of very late definite/probable ST between 1 and 5 years with the BES. © 2015 Wiley Periodicals, Inc.
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AIMS Newer-generation drug-eluting stents (DES) have been shown to be superior to first-generation DES. Current-generation DES have zotarolimus, everolimus or biolimus as antiproliferative drugs. Novolimus, a metabolite of sirolimus, has been specifically developed to provide efficacy similar to currently available agents at a lower dose and thus requires a lower polymer load. We report the final five-year outcomes of the EXCELLA II trial comparing a zotarolimus-eluting stent (ZES) with a novolimus-eluting stent (NES). METHODS AND RESULTS EXCELLA II is a prospective, multicentre, single-blind, non-inferiority clinical trial. Patients (n=210) with a maximum of two de novo lesions in two different epicardial vessels were randomised (2:1) to treatment with either NES (n=139) or ZES (n=71). At five-year follow-up, patients in the NES group had a significantly lower incidence of the patient-oriented (HR 0.53, 95% CI: 0.32-0.87, p=0.013) and device-oriented (HR 0.38, 95% CI: 0.17-0.83, p=0.011) composite endpoints. There was no difference in cardiac death and definite/probable stent thrombosis between the two groups; however, there was a trend towards reduction in myocardial infarction and repeat revascularisation in the NES group at five-year follow-up. CONCLUSIONS At five-year follow-up, the incidence of device- and patient-oriented events was significantly lower in the NES group. Further studies, adequately powered for clinical outcomes, are warranted. TRIAL REGISTRATION ClinicalTrials.gov number NCT00792753.
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Welsch (Projektbearbeiter): Zustimmende Kommentierung der Demonstration vom 5. Oktober 1848 gegen das Bürgerwehrgesetz; vorgetragen in einem Ton gespielter Entrüstung
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Tricho-rhino-phalangeal syndrome (TRPS) is characterized by craniofacial and skeletal abnormalities, and subdivided in TRPS I, caused by mutations in TRPS1, and TRPS II, caused by a contiguous gene deletion affecting (amongst others) TRPS1 and EXT1. We performed a collaborative international study to delineate phenotype, natural history, variability, and genotype-phenotype correlations in more detail. We gathered information on 103 cytogenetically or molecularly confirmed affected individuals. TRPS I was present in 85 individuals (22 missense mutations, 62 other mutations), TRPS II in 14, and in 5 it remained uncertain whether TRPS1 was partially or completely deleted. Main features defining the facial phenotype include fine and sparse hair, thick and broad eyebrows, especially the medial portion, a broad nasal ridge and tip, underdeveloped nasal alae, and a broad columella. The facial manifestations in patients with TRPS I and TRPS II do not show a significant difference. In the limbs the main findings are short hands and feet, hypermobility, and a tendency for isolated metacarpals and metatarsals to be shortened. Nails of fingers and toes are typically thin and dystrophic. The radiological hallmark are the cone-shaped epiphyses and in TRPS II multiple exostoses. Osteopenia is common in both, as is reduced linear growth, both prenatally and postnatally. Variability for all findings, also within a single family, can be marked. Morbidity mostly concerns joint problems, manifesting in increased or decreased mobility, pain and in a minority an increased fracture rate. The hips can be markedly affected at a (very) young age. Intellectual disability is uncommon in TRPS I and, if present, usually mild. In TRPS II intellectual disability is present in most but not all, and again typically mild to moderate in severity. Missense mutations are located exclusively in exon 6 and 7 of TRPS1. Other mutations are located anywhere in exons 4-7. Whole gene deletions are common but have variable breakpoints. Most of the phenotype in patients with TRPS II is explained by the deletion of TRPS1 and EXT1, but haploinsufficiency of RAD21 is also likely to contribute. Genotype-phenotype studies showed that mutations located in exon 6 may have somewhat more pronounced facial characteristics and more marked shortening of hands and feet compared to mutations located elsewhere in TRPS1, but numbers are too small to allow firm conclusions.
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Rare event search experiments using liquid xenon as target and detection medium require ultra-low background levels to fully exploit their physics potential. Cosmic ray induced activation of the detector components and, even more importantly, of the xenon itself during production, transportation and storage at the Earth's surface, might result in the production of radioactive isotopes with long half-lives, with a possible impact on the expected background. We present the first dedicated study on the cosmogenic activation of xenon after 345 days of exposure to cosmic rays at the Jungfraujoch research station at 3470m above sea level, complemented by a study of copper which has been activated simultaneously. We have directly observed the production of 7Be, 101Rh, 125Sb, 126I and 127Xe in xenon, out of which only 125Sb could potentially lead to background for a multi-ton scale dark matter search. The production rates for five out of eight studied radioactive isotopes in copper are in agreement with the only existing dedicated activation measurement, while we observe lower rates for the remaining ones. The specific saturation activities for both samples are also compared to predictions obtained with commonly used software packages, where we observe some underpredictions, especially for xenon activation.
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We measured carbon, nitrogen, protein, bacterial and microalgal abundance, and mineral-specific surface area in sediments from the feeding zone of undisturbed Saccoglossus kowalewskyi, as well as in their fresh egesta. Comparison of results using surficial material 1 mm) and the top 3 mm of sediments indicated ingestion of surficial material by the enteropneusts. Assuming the surficial sediment as a food source results in apparent absorption efficiencies of 15% for TOC, 35% for TON, 60% for protein and 86% for microalgae. The C:N ratio of the apparently absorbed material was 4.2, consistent with an amino acid-rich diet. Protein- nitrogen uptake, however, accounted for only about 28% of total nitrogen absorption, indicating a dominant use of non-protein nitrogen . Bacterial and microalgal contributions to dietary nitrogen uptake were no more than 3% and 4% respectively. Active worms maintain 2 foraging areas with an average total foraging volume of 0.9 cm3 and a volume ingestion rate of 0.06 to 0.12 cm3 ind.-1 h-1. If the preferred feeding zone of these enteropneusts is the nitrogen -enriched surficial layer, we estimate that their feeding activities will deplete the available food resources every 8 to 16 h and they may rely on biological and tidal redistribution of surface material.
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Es motivo del presente trabajo analizar al fideicomiso como herramienta para el desarrollo de un sector de la economía provincial de marcada importancia como lo es el de la construcción. En la actualidad vemos como este sector ha tomado relevancia e impulso y es por eso la necesidad de encontrar una figura que acompañe esta tendencia. El objetivo principal es analizar la fiducia inmobiliaria, como medio para sustentar un negocio, como así también explicar los motivos por los cuales este contrato podría convertirse en un medio usual en el mencionado sector, ya que si bien está siendo utilizado, aún existe desconocimiento de los beneficios que provee, fruto de una legislación muy joven.
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El presente trabajo tiene como finalidad poner de manifiesto la utilidad del fideicomiso en el financiamiento de una empresa. No pretende agotar el tema, sino brindar una descripción acerca de esta herramienta para posibilitarle al lector un mayor conocimiento de la misma, adoptando un enfoque netamente jurídico. Teniendo esto presente, en el capítulo primero se exponen someramente los lineamientos legales y doctrinarios del fideicomiso en general para así brindar un acercamiento de la terminología y fijar precisiones conceptuales. Luego se describen los distintos tipos de fideicomiso, con el fin de mostrar la flexibilidad de la figura en la aplicación empírica. Siendo conscientes de las diversas aplicaciones en el financiamiento de los entes del fideicomiso, luego, en el capítulo segundo, nos centramos en el fideicomiso financiero, por considerar que es el de mayor aplicación en el objeto del presente trabajo. Del mismo, exponemos las distintas posturas doctrinarias que analizan la normativa respectiva. Además, en este capítulo nos pareció conveniente dedicar unos párrafos al fenómeno de la securitización, ya que consideramos que para un acabado entendimiento del propósito de este trabajo es necesario el conocimiento del mismo.
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El presente trabajo de investigación abordará el estudio y análisis del uso del fideicomiso como herramienta de financiación e inversión en el sector de la construcción en Argentina. Debido a que los fideicomisos contribuyeron al desarrollo y al crecimiento del país luego de la crisis del 2001 y 2002, es que nos resultó interesante analizar esta herramienta. Para ello realizamos una investigación bibliográfica adecuada comenzando con una breve reseña histórica, siguiendo con los aspectos básicos del fideicomiso hasta profundizar en el fideicomiso inmobiliario. Además se realizaron entrevistas con especialistas con el fin de obtener información respecto de la evolución de la construcción en la República Argentina y Mendoza complementándose con un análisis estadístico. Con toda la documentación analizada pudimos determinar los pasos a seguir para llevar a cabo un fidecomiso inmobiliario en la práctica y destacar los aspectos más importantes a tener presentes al momento de realizarlo. De esta manera pretendemos demostrar, en base a toda la información analizada, que efectivamente el fideicomiso inmobiliario es una herramienta útil en la actividad de la construcción.