988 resultados para Hybrid cycle


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In this paper a hybrid solid oxide fuel cell (SOFC) system is analyzed. This system applies a combined cycle utilizing gas turbine associated to a SOFC for rational decentralized energy production. Initially the relative concepts about the fuel cell are presented, followed by some chemical and technical informations such as the change of Gibbs free energy in isothermal fuel oxidation (or combustion) directly into electricity. This represents a very high fraction of the lower heating value (LHV) of a hydrocarbon fuel. In the next step a methodology for the study of SOFC associated with a gas turbine system is developed, considering the electricity and steam production for a hospital, as regard to the Brazilian conditions. This methodology is applied to energetic analysis. Natural gas is considered as a fuel. In conclusion, it is shown by a Sankey Diagram that the hybrid SOFC system may be an excellent opportunity to strengthen the decentralized energy production in Brazil. It is necessary to consider that the cogeneration in this version also is a sensible alternative from the technical point of view, demanding special methods of design, equipment selection and mainly of the contractual deals associated to electricity and fuel supply.

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The interest in reducing maize row spacing in the short growing season regions of Brazil is increasing due to potential advantages such as higher radiation use efficiency. This experiment was conducted to evaluate the effect of row spacing reduction on grain yield of different maize cultivars planted at different dates. The trial was conducted in Lages, in the State of Santa Catarina, Brazil, during 1996/97 and 1997/98 growing seasons, in a split-split plot design. Early (October 1st) and normal (November 15) planting dates were tested in the main plot; two morphologically contrasting cultivars (an early single-cross and a late double-cross hybrids) were evaluated in the split plots and three row widths (100, 75 and 50 cm) were studied in the split-split plots. The reduction of row spacing from 100 to 50 cm increased linearly maize grain yield. The yield edge provided by narrow rows was higher when maize was sown earlier in the season. Differences in hybrid cycle and plant architecture did not alter maize response to the reduction of row spacing.

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O objetivo deste trabalho foi avaliar o efeito do consórcio com capim-marandu (Urochloa brizantha) na nutrição e produtividade de híbridos de sorgo granífero de ciclos contrastantes, em sistema plantio direto. Utilizou-se o delineamento experimental de blocos ao acaso, em arranjo fatorial 2x2, com seis repetições. Os tratamentos consistiram de dois híbridos de sorgo granífero de ciclos contrastantes (P8118, ciclo médio; e P8419, ciclo precoce) e dois sistemas de cultivo (monocultivo e consórcio com capim-marandu na linha de semeadura), com semeadura no início de dezembro. Avaliou-se a nutrição, as características agronômicas, os componentes da produção e a produtividade de matéria seca e grãos da cultura do sorgo. Com exceção do potássio e do enxofre, os teores foliares dos demais nutrientes foram adequados à cultura do sorgo granífero, em todos os tratamentos. O híbrido P8118 apresentou a maior produtividade de grãos e, após o consórcio, contribuiu para a maior produtividade de matéria seca da forragem de capim-marandu, no corte realizado em outubro. O cultivo consorciado com capim-marandu não afeta a nutrição e a produtividade de matéria seca e de grãos de sorgo, em comparação ao monocultivo, independentemente do ciclo do híbrido utilizado.

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Die Luftverschmutzung, die globale Erwärmung sowie die Verknappung der endlichen Ressourcen sind die größten Bedenken der vergangenen Jahrzehnte. Die Nachfrage nach jeglicher Mobilität steigt rapide. Dementsprechend bemüht ist die Automobilindustrie Lösungen für Mobilität unter dem Aspekt der Nachhaltigkeit und dem Umweltschutz anzubieten. Die Elektrifizierung hat sich hierbei als der beste Weg herausgestellt, um die Umweltprobleme sowie die Abhängigkeit von fossilen Brennstoffen zu lösen. Diese Arbeit soll einen Einblick über die Umweltauswirkungen des Hybridfahrzeuges Toyota Prius geben. Hierbei findet eine Gliederung in vier verschiedene Lebensphasen statt. Im Anschluss bietet die Sachbilanz die Möglichkeit die Umweltauswirkungen mit verschiedenen Antriebsmöglichkeiten und Brennstoffen zu vergleichen. Das Modell hat gezeigt, dass der Toyota Prius während der Nutzung einen hohen Einfluss auf das Treibhauspotenzial aufweist. Durch die Nutzung anderer Brennstoffe, wie beispielsweise Ethanol oder Methanol lassen sich die Auswirkungen am Treibhauspotenzial sowie der Verbrauch an abiotischen Ressourcen reduzieren. Vergleicht man die Elektromobilität mit der konventionellen, so ist festzustellen, dass diese Art der Mobilität die derzeit beste Möglichkeit zur Reduzierung der Umweltbelastungen bietet. Die Auswirkungen der Elektromobilität sind im hohen Maße abhängig von der Art des verwendeten Strommixes.

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The effect of shot particles on the high temperature, low cycle fatigue of a hybrid fiber/particulate metal-matrix composite (MMC) was studied. Two hybrid composites with the general composition A356/35%SiC particle/5%Fiber (one without shot) were tested. It was found that shot particles acting as stress concentrators had little effect on the fatigue performance. It appears that fibers with a high silica content were more likely to debond from the matrix. Final failure of the composite was found to occur preferentially in the matrix. SiC particles fracture progressively during fatigue testing, leading to higher stress in the matrix, and final failure by matrix overload. A continuum mechanics based model was developed to predict failure in fatigue based on the tensile properties of the matrix and particles. By accounting for matrix yielding and recovery, composite creep and particle strength distribution, failure of the composite was predicted.

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© Medina et al.Although cell cycle control is an ancient, conserved, and essential process, some core animal and fungal cell cycle regulators share no more sequence identity than non-homologous proteins. Here, we show that evolution along the fungal lineage was punctuated by the early acquisition and entrainment of the SBF transcription factor through horizontal gene transfer. Cell cycle evolution in the fungal ancestor then proceeded through a hybrid network containing both SBF and its ancestral animal counterpart E2F, which is still maintained in many basal fungi. We hypothesize that a virally-derived SBF may have initially hijacked cell cycle control by activating transcription via the cis-regulatory elements targeted by the ancestral cell cycle regulator E2F, much like extant viral oncogenes. Consistent with this hypothesis, we show that SBF can regulate promoters with E2F binding sites in budding yeast.

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Layer-by-layer (LBL) assembly was used to combine crystalline rod-like nanoparticles obtained from a vegetable source, cellulose nanowhiskers (CNWs), with collagen, the main component of skin and connective tissue found exclusively in animals. The film growth of the multilayered collagen/CNW was monitored by UV-Vis spectroscopy and ellipsometry measurements, whereas the film morphology and surface roughness were characterized by SEM and AFM. UV-Vis spectra showed the deposition of the same amount of collagen, 5 mg m(-2), in each dipping cycle. Ellipsometry data showed an increment in thickness with the number of layers, and the average thickness of each bilayer was found to be 8.6 nm. The multilayered bio-based nanocomposites were formed by single layers of densely packed CNWs adsorbed on top of each thin collagen layer where the hydrogen bonding between collagen amide groups and OH groups of the CNWs plays a mandatory role in the build-up of the thin films. The approach used in this work represents a potential strategy to mimic the characteristics of natural extracellular matrix (ECM) which can be used for applications in the biomedical field.

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Water use and crop coefficient for hybrid DKB 390. This work aims to characterize the water use of maize hybrid DKB 390 under suitable conditions of irrigation for both sufficient and below-optimal situations of nitrogen supply. Crop coefficient values for different stages are also presented as a result, in order to provide the basis for crop water budget and management throughout the cycle. A field experiment was carried Out during the main season, in which biomass, soil moisture, leaf area, climate data and light transmittance were evaluated. These have allowed deriving water balance, use and efficiency. The mentioned genotype requires around 600 nun for high yield targets, being less efficient when led under below-optimal nitrogen fertilization.

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Intraspecific Drosophila studies suggest that resistance to heal and cold stresses are largely independent and that correlations across life cycle stages are low whereas comparisons of Drosophila species indicate correlations between heat and cold resistance as well as between resistance levels in different life cycle stages. These inconsistent results may reflect differences in associations among traits at the interspecific and intraspecific levels or interspecific correlations arising because of correlated selection pressures. These alternatives were tested using Drosophila serrata, D. birchii and hybrids derived from these species. Variation among hybrid lines and families was used to test associations at the interspecific level while intraspecific variation was examined using isofemale lines of D. serrata. There was a significant association between adult heat knockdown time at 38 degreesC and adult cold resistance in one set of hybrid lines. An association between female knockdown resistance to heat and larval heat resistance was also evident in one set of hybrids. Resistance to heat anti cold at the larval stage were not correlated at either the intraspecific or interspecific levels. At the intraspecific level, lan al heat resistance and two measures of adult heat resistance were uncorrelated. Moreover, adult and larval cold resistance measures were not correlated at either the intraspecific or interspecific levels. These results suggest that there are no associations between resistance to heat and cold extremes and that extreme temperature resistance is largely independent across life cycle stages at both the intraspecific and interspecific levels. Species associations may therefore arise from correlated selection pressures rather than trait correlations. (C) 2000 The Linnean Society of London.

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Illegitimate V(D)J-recombination in lymphoid malignancies involves rearrangements in immunoglobulin or T-cell receptor genes, and these rearrangements may play a role in oncogenic events. High frequencies of TRGV-BJ hybrid gene (rearrangement between the TRB and TRG loci at 7q35 and 7p14-15, respectively) have been detected in lymphocytes from patients with ataxia telangiectasia (AT), and also in patients with lymphoid malignancies. Although the TRGV-BJ gene has been described only in T-lymphocytes, we previously detected the presence of TRGV-BJ hybrid gene in the genomic DNA extracted from SV40-transformed AT5BIVA fibroblasts from an AT patient. Aiming to determine whether the AT phenotype or the SV40 transformation could be responsible for the production of the hybrid gene by illegitimate V(D)J-recombination, DNA samples were extracted from primary and SV40-transformed (normal and AT) cell lines, following Nested-PCR with TRGV- and TRBJ-specific primers. The hybrid gene was only detected in SV40-transformed fibroblasts (AT-5BIVA and MRC-5). Sequence alignment of the cloned PCR products using the BLAST program confirmed that the fragments corresponded to the TRGV-BJ hybrid gene. The present results indicate that the rearrangement can be produced in nonlymphoid cells, probably as a consequence of the genomic instability caused by the SV40-transformation, and independently of ATM gene mutation.

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Mussel populations on the Irish Atlantic coast comprise an interbreeding mixture of the blue mussel, Mytilus edulis (L.) and the Mediterranean mussel, Mytilus galloprovincialis (Lmk.). The occurrence of hybrid genotypes varies between sites but can be as high 80%. This study compares the reproductive cycle of M. edulis, M. galloprovincialis and their hybrids to determine if the extensive hybridisation observed at Irish Atlantic coast sites is linked to spawning synchrony between the two taxa. Mussels (40-45 mm size class) were collected monthly from a sheltered shore in Galway Bay from January to December 2005. Two major spawning events (March- June and September-October) were observed and gametogenesis took place throughout the year. The spawning cycles of the three taxa were largely overlapping. Small differences were observed in the timing of peak spawning which occurred in March and October in M. galloprovincialis and in May-June and September in M.edulis. Spawning of hybrid individuals was intermediate between the parental genotypes. Fecundity was slightly higher in M. galloprovincialis females compared to the other taxa (up to 30% difference, p<0.05). This apparent advantage is not shared by the sexes and is likely being offset by high numbers of hybrid genotypes releasing gametes during peak spawning of M. galloprovincialis. There was no evidence for increased mortality in hybrid males; sex ratios did not deviate from the 1:1 ratio. The results show that in this region of the hybrid zone the timing of reproduction does not present a barrier to gene flow between M. edulis and M. galloprovincialis. Nonetheless, small differences in the timing of peak spawning may increase the likelihood of conspecific fertilisation at certain times of the year. Hybrids outnumber the parental genotypes, undergo complete gametogenesis and show no evidence of depressed fitness (i.e. hybrids are reproductively competent suggesting a high degree of introgression.

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This paper contributes to the on-going empirical debate regarding the role of the RBC model and in particular of technology shocks in explaining aggregate fluctuations. To this end we estimate the model’s posterior density using Markov-Chain Monte-Carlo (MCMC) methods. Within this framework we extend Ireland’s (2001, 2004) hybrid estimation approach to allow for a vector autoregressive moving average (VARMA) process to describe the movements and co-movements of the model’s errors not explained by the basic RBC model. The results of marginal likelihood ratio tests reveal that the more general model of the errors significantly improves the model’s fit relative to the VAR and AR alternatives. Moreover, despite setting the RBC model a more difficult task under the VARMA specification, our analysis, based on forecast error and spectral decompositions, suggests that the RBC model is still capable of explaining a significant fraction of the observed variation in macroeconomic aggregates in the post-war U.S. economy.

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SUMMARY LATS2 is a member of the Lats tumour suppressor gene family. The human LATS2 gene is located at chromosome 13q11-12, which has been shown to be a hot spot (67%) for LOH in nonsmall cell lung cancer. Both lats mosaic flies and LATS1 deficient mice spontaneously develop tumours, an observation that is explained by the function of LATS1 in suppressing tumourigenesis by negatively regulating cell proliferation by modulating Cdc2/Cyclin A activity. LATS1 also plays a critical role in maintenance of ploidy through its action on the spindle assembly checkpoint. Initial insights into the function of LATS2 reveals that the protein is involved in the G2/M transition of the cell cycle, whereby it controls the phosphorylation status of Cdc25C. The aim of the present study was to identify LATS2 interacting partners that would provide a more thorough understanding of the molecular pathways in which the protein is involved. The yeast two-hybrid system identified a number of candidate genes that interact with LATS2. Most of the interactions were confirmed biochemically by GST-pull down assays that enabled us to demonstrate that LATS2 is an integral component of the Signalosome complex. The Signalosome is thought to be required for the establishment of functional Cullin-based E3 ubiquitin ligases, the substrate-recognition elements of the ubiquitin-mediated protein proteolytic pathway. The findings that LATS2 also interacts with all of the components of the E3 enzymes allows us to postulate that LATS2 is probably involved in the regulation of this Signalosome-E3 super-complex. In addition, the discovery that LATS2 associates with multiple protein kinases localised at the cellular membrane and in various signalling cascades supports the idea that LATS2 functions as an integrator of signals which allows it to monitor the activity of these pathways and translate these signals through its action on the Signalosome. Furthermore, the observation that a kinase-dead LATS2 mutant arrests at the G2/M phase of the cell cycle, demonstrates that the protein, through the action of its kinase domain, is crucial for progression through the cell cycle, an action in accordance to its proposed role as a regulator of E3 ubiquitin ligases. The findings presented herein provide evidence that LATS2 associates with the Signalosome-E3 ubiquitin ligases super-complex which governs protein stability. Any alteration of the protein would have a strong impact on pathways that modulate cell proliferation, as shown by its implication in tumourigenesis. RESUME LATS2 est un membre de la famille de gènes suppresseurs de tumeurs LATS. Le gène humain LATS2 est situé sur le chromosome 13q11-12, une région qui s'est avérée être un point sensible (67%) dans la perte d'hétérozigosité (LOH) notamment pour le cancer du poumon. Le fait que des tumeurs se développent spontanément chez les souris qui sont déficientes pour le gène LATS1 ainsi que dans des cellules mutantes pour LATS chez la Drosophile, est expliqué Par la fonction de LATS1, qui est de supprimer l'apparition de tumeurs en réprimant la prolifération cellulaire à travers sa capacité à réguler l'activité de Cdc2/Cyciine A. LATS1 joue également un rôle important au niveau du maintient de la ploïdie de la cellule, au travers de son action sur les points de contrôle de l'assemblage du fuseau mitotique. Les premières études du gène LATS2 indiquent que la protéine est, par son contrôle des réactions de phosphorylation de la Cdc25C, impliquée dans la transition 021M. Le but de cette étude était d'identifier les protéines qui interagissent avec LATS2, en vue d'obtenir une compréhension plus approfondie des mécanismes moléculaires dans lesquels LATS2 se trouve engagée. Le système de double-hybride chez la levure a permis l'identification d'un grand nombre de gènes qui interagissent avec LATS2. La plupart des interactions ont été confirmées par GST «pull clown», une technique in vitro qui a permis de démontrer que LATS2 est un composant intégral du Signalosome. Ce complexe est supposé réguler l'activité des E3 ubiquitine-rigases, les éléments responsables du recrutement des substrats qui doivent être recyclés par la voie de dégradation ubiquitine-dépendante. Les résultats obtenus indiquent également que LATS2 interagit avec tous les composants des enzymes E3, ce qui nous permet de soumettre l'idée selon laquelle la protéine LATS2 est en fait impliquée dans la régulation du complexe Signalosorne-E3. De plus, la découverte que LATS2 se trouve associée à plusieurs protéines kinases localisées au niveau de la membrane cellulaire, ainsi que dans diverses voies de transduction, confirment l'idée que LATS2 fonctionne en tant que molécule qui intègre les signaux en provenance de ces différentes voies cellulaires. De ce fait, il lui serait possible de coordonner la destruction des protéines au moyen du complexe Signalosome, permettant ainsi de réprimer l'activité des voies de signalisation. En outre, l'introduction d'une mutation dans le domaine kinase de LATS2 résulte en l'arrêt du cycle cellulaire en G2/M, ce qui montre que la protéine, au travers de son domaine kinase, est cruciale pour le bon fonctionnement du cycle cellulaire, ceci en accord avec son rôle proposé comme régulateur des E3 ubiquitine-ligases. Les résultats présentés dans ce manuscrit démontrent que la protéine LATS2 se trouve associée au complexe Signalosome-E3 qui régule la dégradation des protéines. La moindre modification de la protéine engendrerait des répercussions importantes au niveau des voies de transduction qui contrôlent fa prolifération ceilulaire, ce qui atteste du rôle déterminant que joue LAT32 dans la tumorigénèse.

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Information about nutrient extraction and exportation by crops, as well as the periods of highest nutrient demand is important for an adequate fertilization management. However, there are no studies on the nutrient uptake of short-stature hybrid castor bean. Therefore, the purpose of this study was to evaluate nutrient extraction and exportation by short-stature castor bean hybrid Lyra, in the spring-summer and fall-winter growing seasons. The experiments were conducted in the 2005/2006 spring-summer and 2006 fall-winter growing seasons on an Oxisol, in Botucatu, SP, in a randomized block design, with four replications. The plots consisted of plant samplings, which occurred 17, 31, 45, 59, 73, 97 and 120 days after emergence (DAE) in the spring-summer and 17, 31, 45, 59, 80, 100 and 120 DAE in fall-winter growing season. The growth of hybrid Lyra was slow and nutrient uptake lowest between emergence and the beginning of flowering. The period of highest dry matter (DM) accumulation rates and highest nutrient demand were observed 40 to 80 DAE, in both growing seasons. The order of nutrient extraction by the plants in the spring-summer growing season was: N>K>Ca>Mg>S>P>Fe>Mn>Zn>B>Cu>Mo. In fall-winter, S was more absorbed than Mg. Seed yield was higher in the spring-summer (2.995 kg ha-1), but nutrient extraction and exportation per ton of seed were similar in both growing seasons. Around 58 % of N and 84 % of P, and approximately half of the S and B absorbed throughout the cycle were exported with the seeds. However, most of the other nutrients accumulated in the plants returned to the soil in plant residues.

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Background, aim, and scope A coupled Life Cycle Costing and life cycle assessment has been performed for car-bodies of the Korean Tilting Train eXpress (TTX) project using European and Korean databases, with the objective of assessing environmental and cost performance to aid materials and process selection. More specifically, the potential of polymer composite car-body structures for the Korean Tilting Train eXpress (TTX) has been investigated. Materials and methods This assessment includes the cost of both carriage manufacturing and use phases, coupled with the life cycle environmental impacts of all stages from raw material production, through carriage manufacture and use, to end-of-life scenarios. Metallic carriages were compared with two composite options: hybrid steel-composite and full-composite carriages. The total planned production for this regional Korean train was 440 cars, with an annual production volume of 80 cars. Results and discussion The coupled analyses were used to generate plots of cost versus energy consumption and environmental impacts. The results show that the raw material and manufacturing phase costs are approximately half of the total life cycle costs, whilst their environmental impact is relatively insignificant (3-8%). The use phase of the car-body has the largest environmental impact for all scenarios, with near negligible contributions from the other phases. Since steel rail carriages weigh more (27-51%), the use phase cost is correspondingly higher, resulting in both the greatest environmental impact and the highest life cycle cost. Compared to the steel scenario, the hybrid composite variant has a lower life cycle cost (16%) and a lower environmental impact (26%). Though the full composite rail carriage may have the highest manufacturing cost, it results in the lowest total life cycle costs and lowest environmental impacts. Conclusions and recommendations This coupled cost and life cycle assessment showed that the full composite variant was the optimum solution. This case study showed that coupling of technical cost models with life cycle assessment offers an efficient route to accurately evaluate economic and environmental performance in a consistent way.