337 resultados para CSP


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Icy debris fans have are newly-described landforms (Kochel and Trop, 2008 and 2012) as landforms developed immediately after deglaciation on Earth and similar features have been observed on Mars. Subsurface characteristics of Icy debris fans have not been previously investigated. Ground penetrating radar (GPR) was used to non-invasively investigate the subsurface characteristics of icy debris fans near McCarthy, Alaska, USA. The three fans investigated in Alaska are the East, West, and Middle fans (Kochel and Trop, 2008 and 2012) which below the Nabesna ice cap and on top of the McCarthy Creek Glacier. Icy debris fans in general are a largely unexplored suite of paraglacial landforms and processes in alpine regions. Recent field studies focused on direct observations and depositional processes. Their results showed that the fan's composition is primarily influenced by the type and frequency of depositional processes that supply the fan. Photographic studies show that the East Fan receives far more ice and snow avalanches whereas the Middle and West Fans receive fewer mass wasting events but more clastic debris is deposited on the Middle and West fan from rock falls and icy debris flows. GPR profiles and Wide-angle reflection and refraction (WARR) surveys consisting of both, common mid-point (CMP), and common shot-point (CSP) surveys investigated the subsurface geometry of the fans and the McCarthy Creek Glacier. All GPR surveys were collected in July of 2013 with 100MHz bi-static antennas. Four axial profiles and three cross-fan profiles were done on the West and Middle fans as well as the McCarthy Creek Glacier in order to investigate the relationship between the three features. GPR profiles yielded reflectors that were continuous for 10+ m and hyperbolic reflections in the subsurface. The depth to these reflections in the subsurface requires knowledge of the velocity of the subsurface. To find the velocity of the subsurface eight WARR surveys collected on the fans and on the McCarthy Creek glacier to provide information on variability of subsurface velocities. The profiles of the Middle and West fan have more reflections in their profiles compared to profiles done on the McCarthy Creek Glacier. Based on the WARR surveys, we interpret the lower energy return in the glacier to be caused by two reasons. 1) The increased attenuation due to wet ice versus drier ice and on the fan with GPR velocities >0.15m/ns. 2) Lack of interfaces in the glacier compared to those in the fans which are inferred to be produced by the alternating layers of stratified ice and lithic-rich layers. The GPR profiles on the West and Middle Fans show the shallow subsurface being dominated by lenticular reflections interpreted to be consistent with the shape of surficial deposits. The West Fan is distinguished from the Middle Fan by the nature of its reflections patterns and thicknesses of reflection packages that clearly shows the Middle fan with a greater thickness. The changes in subsurface reflections between the Middle and West Fans as well as the McCarthy Creek Glacier are thought to reflect the type and frequency of depositional processes and surrounding bedrock and talus slopes.

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In Streptococcus pneumoniae expression of pyruvate oxidase (SpxB) peaks during the early growth phase, coincident with the time of natural competence. This study investigated whether SpxB influences parameters of competence, such as spontaneous transformation frequency, expression of competence genes, and DNA release. Knockout of the spxB gene in strain D39 abolished spontaneous transformation (compared to a frequency of 6.3 x 10(-6) in the parent strain [P < 0.01]). It also reduced expression levels of comC and recA as well as DNA release from bacterial cells significantly during the early growth phase, coincident with the time of spontaneous competence in the parent strain. In the spxB mutant, supplementation with competence-stimulating peptide 1 (CSP-1) restored transformation (rate, 1.8 x 10(-2)). This speaks against the role of SpxB as a necessary source of energy for competence. Neither supplementation with CSP-1 nor supplementation with the SpxB products H2O2 and acetate altered DNA release. Supplementation of the parent strain with catalase did not reduce DNA release significantly. In conclusion, the pneumococcal spxB gene influences competence; however, the mechanism remains elusive.

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Stetig steigende Funktionalitäten, intelligente Materialien, eine möglichst geringe Leistungsaufnahme verbunden mit kleinem Volumen und geringem Gewicht sind die zentralen Anforderungen u.a. der Medizintechnik und der Telekommunikation. Um diesen Bedarf mit industriellen Fertigungsverfahren abzudecken, startete das Unternehmen nach seiner Gründung in Rumeln bereits 1996 mit dem Aufbau der RMPD® Technologiefamilie. Heute sichern diese Technologien, mit denen die direkte Serienproduktion auf Basis der CAD Kontruktionsdaten für Mikrosysteme und –komponenten werkzeuglos erfolgt, einem internationalen Kundenkreis Markterfolge mit dem Einsatz patentierter Fertigungssysteme. microTEC ist an zwei Standorten als Auftragsproduzent für Unternehmen u.a. aus den Bereichen Sensorik, Telekommunikation, Medizintechnik und Biotechnologie tätig. Mit den RMPD® Technologien profitieren die Kunden auch durch die schnelle Anpassungsfähigkeit an sich ändernde Marktbedingungen und Verbraucherwünsche. Über 300 Kunststoffe mit den unterschiedlichsten Eigenschaften stehen für mikroelektronische Packaging-Dienstleistungen und Auftragsfertigung von Mikrosystemen zur Verfügung, zu den Produkten gehören z.B. Mikrogetriebe mit selbstschmierenden Zahnrädern und Lab-on-a-Chipsysteme, die mit dem Einsatz hydrophiler Kunststoffe die Kapillarwirkung auch in 3D nutzen. Die beiden Geschäftsführer Dipl. Ing. Reiner Götzen und Andrea Reinhardt, sowie der Prokurist Dr. Ing. Helge Bohlmann stehen für eine konzernunabhängige, kundenorientierte Strategie und verfügen über langjährige Erfahrung als mittelständische Unternehmer. Dies bildet zusammen mit der internationalen Marktorientierung, dem branchenübergreifenden Technologie Know-how und den inhouse verfügbaren Produktionsanlagen die Basis für den weiteren Standortausbau im 8. Jahr des Unternehmens.

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Protection against malaria can be achieved by induction of a strong CD8(+) T-cell response against the Plasmodium circumsporozoite protein (CSP), but most subunit vaccines suffer from insufficient memory responses. In the present study, we analyzed the impact of postimmunization sporozoite challenge on the development of long-lasting immunity. BALB/c mice were immunized by a heterologous prime/boost regimen against Plasmodium berghei CSP that induces a strong CD8(+) T-cell response and sterile protection, which is short-lived. Here, we show that protective immunity is prolonged by a sporozoite challenge after immunization. Repeated challenges induced sporozoite-specific antibodies that showed protective capacity. The numbers of CSP-specific CD8(+) T cells were not substantially enhanced by sporozoite infections; however, CSP-specific memory CD8(+) T cells of challenged mice displayed a higher cytotoxic activity than memory T cells of immunized-only mice. CD4(+) T cells contributed to protection as well; but CD8(+) memory T cells were found to be the central mediator of sterile protection. Based on these data, we suggest that prolonged protective immunity observed after immunization and infection is composed of different antiparasitic mechanisms including CD8(+) effector-memory T cells with increased cytotoxic activity as well as CD4(+) memory T cells and neutralizing antibodies.

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Partial phallectomy or en bloc resection are surgical methods to address pathological conditions of the penis and/or prepuce including neoplasia, trauma, habronemiasis, chronic paraphimosis or permanent penile paralysis, and priapism. Haemorrhage associated with urination is a common complication observed after penile surgery but usually resolves spontaneously without specific treatment. This report describes a case of post urination haemorrhage (PUH) that recurred with each urination and persisted without significant improvement for a period of 2 weeks following en bloc resection of the penis and the prepuce. A perineal incision (PI) into the corpus spongiosum of the penis (CSP) resolved PUH by decreasing the blood pressure in the CSP distal to the PI. We propose that PI of the CSP can be an effective method to address PUH after penile surgery and may decrease time of hospitalisation for horses affected with PUH after phallectomy procedures.

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Regulatory T cells (T(reg)) have been shown to restrict vaccine-induced T cell responses in different experimental models. In these studies CD4(+)CD25(+) T(reg) were depleted using monoclonal antibodies against CD25, which might also interfere with CD25 on non-regulatory T cell populations and would have no effect on Foxp3(+)CD25(-) T(reg). To obtain more insights in the specific function of T(reg) during vaccination we used mice that are transgenic for a bacterial artificial chromosome expressing a diphtheria toxin (DT) receptor-eGFP fusion protein under the control of the foxp3 gene locus (depletion of regulatory T cell mice; DEREG). As an experimental vaccine-carrier recombinant Bordetella adenylate cyclase toxoid fused with a MHC-class I-restricted epitope of the circumsporozoite protein (ACT-CSP) of Plasmodium berghei (Pb) was used. ACT-CSP was shown by us previously to introduce the CD8+ epitope of Pb-CSP into the MHC class I presentation pathway of professional antigen-presenting cells (APC). Using this system we demonstrate here that the number of CSP-specific T cells increases when T(reg) are depleted during prime but also during boost immunization. Importantly, despite this increase of T effector cells no difference in the number of antigen-specific memory cells was observed.

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The Reoviridae virus family is a group of economically and pathologically important viruses that have either single-, double-, or triple-shelled protein layers enclosing a segmented double stranded RNA genome. Each virus particle in this family has its own viral RNA dependent RNA polymerase and the enzymatic activities necessary for the mature RNA synthesis. Based on the structure of the inner most cores of the viruses, the Reoviridae viruses can be divided into two major groups. One group of viruses has a smooth surfaced inner core, surrounded by complete outer shells of one or two protein layers. The other group has an inner core decorated with turrets on the five-fold vertices, and could either completely lack or have incomplete outer protein layers. The structural difference is one of the determinant factors for their biological differences during the infection. ^ Cytoplasmic polyhedrosis virus (CPV) is a single-shelled, turreted virus and the structurally simplest member in Reoviridae. It causes specific chronic infections in the insect gut epithelial cells. Due to its wide range of insect hosts, CPV has been engineered as a potential insecticide for use in fruit and vegetable farming. Its unique structural simplicity, unparalleled capsid stability and ease of purification make CPV an ideal model system for studying the structural basis of dsRNA virus assembly at the highest possible resolution by electron cryomicroscopy (cryoEM) and three-dimensional (3D) reconstruction. ^ In this thesis work, I determined the first 3D structure of CPV capsids using 100 kV cryoEM. At an effective resolution of 17 Å, the full capsid reveals a 600-Å diameter, T = 1 icosahedral shell decorated with A and B spikes at the 5-fold vertices. The internal space of the empty CPV is unoccupied except for 12 mushroom-shaped densities that are attributed to the transcriptional enzyme complexes. The inside of the full capsid is packed with icosahedrally-ordered viral genomic RNA. The interactions of viral RNA with the transcriptional enzyme complexes and other capsid proteins suggest a mechanism for RNA transcription and subsequent release. ^ Second, the interactions between the turret proteins (TPs) and the major capsid shell protein (CSPs) have been identified through 3D structural comparisons of the intact CPV capsids with the spikeless CPV capsids, which were generated by chemical treatments. The differential effects of these chemical treatment experiments also indicated that CPV has a significantly stronger structural integrity than other dsRNA viruses, such as the orthoreovirus subcores, which are normally enclosed within outer protein shells. ^ Finally, we have reconstructed the intact CPV to an unprecendented 8 Å resolution from several thousand of 400kV cryoEM images. The 8 Å structure reveals interactions among the 120 molecules of each of the capsid shell protein (CSP), the large protrusion protein (LPP), and 60 molecules of the turret protein (TP). A total of 1980 α-helices and 720 β-sheets have been identified in these capsid proteins. The CSP structure is largely conserved, with the majority of the secondary structures homologous to those observed in the x-ray structures of corresponding proteins of other reoviruses, such as orthoreovirus and bluetongue virus. The three domains of TP are well positioned to play multifunctional roles during viral transcription. The completely non-equivalent interactions between LPP and CSP and those between the anchoring domain of TP and CSP account for the unparalleled stability of this structurally simplest member of the Reoviridae. ^

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No Brasil, a indução do aborto é legalmente permitida somente quando necessária para salvar a vida da mulher ou quando a concepção ocorreu de estupro. Apesar das restrições legais, morais e religiosas, a indução do aborto é amplamente praticada. Com o objetivo de identificar as características do aborto incompleto nas mulheres admitidas na maternidade pública de Florianópolis, foram entrevistadas 620 mulheres, entre 1o de julho de 1993 e 30 de junho de 1994. Com base em dados coletados por meio de questionário estruturado, são apresentadas características sócio-demográficas, reprodutivas e médicas dos abortos, classificados como certamente provocados, possivelmente provocados e espontâneos. Entre os 141 casos de aborto provocado, cerca de 50% das mulheres reportaram uso isolado do Cytotec® (misoprostol), ou deste associado a outro método abortivo. Os resultados revelam que na população estudada a indução do aborto é prática comum entre mulheres jovens, solteiras ou sem parceiro estável, de bom nível de escolaridade e não usuárias de métodos anticonceptivos. Foi também registrada uma redução do número de complicações graves relacionadas ao aborto provocado admitido ao hospital.

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http://www.scielo.br/pdf/csp/v29n9/a02v29n9.pdf

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Since the early 80's, the sea-surface microlayer (SML) has been hypothesized as being a gelatinous film. Recent studies have confirmed this characteristic, which confers properties that mediate mass and energy fluxes between ocean and atmosphere, including the emission of primary organic aerosols from marine systems. We investigated SML thickness and composition in five replicate indoor experiments between September and December 2010. During each experiment, the SML and underlying seawater were sampled from four seawater tanks: one served as control, and three were inoculated with Thalassiosira weissflogii grown in chemostats at 180, 380 and 780 ppm pCO2. We examined organic material enrichment factors in each tank, paying particular attention to gel particles accumulation such as polysaccharidic Transparent Exopolymer Particles (TEP) and the proteinaceous Coomassie Stainable Particles (CSP). While previous studies have observed carbohydrates and TEP enrichment in the microlayer, little is yet known about proteinaceous gel particles in the SML. Our experiments show that CSP dominate the gelatinous composition of the SML. We believe that the enrichment in CSP points to the importance of bacterial activity in the microlayer. Bacteria may play a pivotal role in mediating processes at the air-sea interface thanks to their exudates and protein content that can be released through cell disruption.

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The sea-surface microlayer (SML) is the ocean's uppermost boundary to the atmosphere and in control of climate relevant processes like gas exchange and emission of marine primary organic aerosols (POA). The SML represents a complex surface film including organic components like polysaccharides, pro- teins, and marine gel particles, and harbors diverse microbial communities. Despite the potential relevance of the SML in ocean-atmosphere interactions, still little is known about its structural characteristics and sen- sitivity to a changing environment such as increased oceanic uptake of anthropogenic CO2. Here we report results of a large-scale mesocosm study, indicating that ocean acidification can affect the abundance and activity of microorganisms during phytoplankton blooms, resulting in changes in composition and dynam- ics of organic matter in the SML. Our results reveal a potential coupling between anthropogenic CO2 emis- sions and the biogenic properties of the SML, pointing to a hitherto disregarded feedback process between ocean and atmosphere under climate change.

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Direct Steam Generation (DSG) in Linear Fresnel (LF) solar collectors is being consolidated as a feasible technology for Concentrating Solar Power (CSP) plants. The competitiveness of this technology relies on the following main features: water as heat transfer fluid (HTF) in Solar Field (SF), obtaining high superheated steam temperatures and pressures at turbine inlet (500ºC and 90 bar), no heat tracing required to avoid HTF freezing, no HTF degradation, no environmental impacts, any heat exchanger between SF and Balance Of Plant (BOP), and low cost installation and maintenance. Regarding to LF solar collectors, were recently developed as an alternative to Parabolic Trough Collector (PTC) technology. The main advantages of LF are: the reduced collector manufacturing cost and maintenance, linear mirrors shapes versus parabolic mirror, fixed receiver pipes (no ball joints reducing leaking for high pressures), lower susceptibility to wind damages, and light supporting structures allowing reduced driving devices. Companies as Novatec, Areva, Solar Euromed, etc., are investing in LF DSG technology and constructing different pilot plants to demonstrate the benefits and feasibility of this solution for defined locations and conditions (Puerto Errado 1 and 2 in Murcia Spain, Lidellin Newcastle Australia, Kogran Creek in South West Queensland Australia, Kimberlina in Bakersfield California USA, Llo Solar in Pyrénées France,Dhursar in India,etc). There are several critical decisions that must be taken in order to obtain a compromise and optimization between plant performance, cost, and durability. Some of these decisions go through the SF design: proper thermodynamic operational parameters, receiver material selection for high pressures, phase separators and recirculation pumps number and location, pipes distribution to reduce the amount of tubes (reducing possible leaks points and transient time, etc.), etc. Attending to these aspects, the correct design parameters selection and its correct assessment are the main target for designing DSG LF power plants. For this purpose in the recent few years some commercial software tools were developed to simulatesolar thermal power plants, the most focused on LF DSG design are Thermoflex and System Advisor Model (SAM). Once the simulation tool is selected,it is made the study of the proposed SFconfiguration that constitutes the main innovation of this work, and also a comparison with one of the most typical state-of-the-art configuration. The transient analysis must be simulated with high detail level, mainly in the BOP during start up, shut down, stand by, and partial loads are crucial, to obtain the annual plant performance. An innovative SF configurationwas proposed and analyzed to improve plant performance. Finally it was demonstrated thermal inertia and BOP regulation mode are critical points in low sun irradiation day plant behavior, impacting in annual performance depending on power plant location.

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This paper presents the theoretical analysis of a storage integrated solar thermophotovoltaic (SISTPV) system operating in steady state. These systems combine thermophotovoltaic (TPV) technology and high temperature thermal storage phase-change materials (PCM) in the same unit, providing a great potential in terms of efficiency, cost reduction and storage energy density. The main attraction in the proposed system is its simplicity and modularity compared to conventional Concentrated Solar Power (CSP) technologies. This is mainly due to the absence of moving parts. In this paper we analyze the use of Silicon as the phase change material (PCM). Silicon is an excellent candidate because of its high melting point (1680 K) and its very high latent heat of fusion of 1800 kJ/kg, which is about ten times greater than the conventional PCMs like molten salts. For a simple system configuration, we have demonstrated that overall conversion efficiencies up to ?35% are approachable. Although higher efficiencies are expected by incorporating more advanced devices like multijunction TPV cells, narrow band selective emitters or adopting near-field TPV configurations as well as by enhancing the convective/conductive heat transfer within the PCM. In this paper, we also discuss about the optimum system configurations and provide the general guidelines for designing these systems. Preliminary estimates of night time operations indicate it is possible to achieve over 10 h of operation with a relatively small quantity of Silicon.

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El presente trabajo fin de grado, que, a partir de ahora, denominaré TFG, consiste en elaborar una monitorización de programas concurrentes en lenguaje Java, para que se visualicen los eventos ocurridos durante la ejecución de los dichos programas. Este trabajo surge en el marco de la asignatura “Concurrencia” de la Escuela Técnica Superior de Ingeniería Informática de la Universidad Politécnica de Madrid, impartida por D. Julio Mariño y D. Ángel Herranz. El objetivo principal de este proyecto es crear una herramienta para el aprendizaje de la asignatura de concurrencia, facilitando la comprensión de los conceptos teóricos, de modo que puedan corregir los posibles errores que haya en sus prácticas. en este proyecto se expone el desarrollo de una librería de visualización de programas concurrentes programados en Java usando un formalismo gráfico similar al empleado en la asignatura. Además esta librería da soporte a los mecanismos de sincronización usados en las prácticas de la asignatura: la librería Monitor (desarrollada por los profesores de la asignatura, D. Ángel Herranz y D. Julio Mariño) y la librería JCSP (Universidad de Kent). ---ABSTRACT---This Bachelor Thesis addresses the problem of monitoring a Java program in order to trace and visualize a certain set of events produced during the execution of concurrent Java programs. This work originates in the subject "Concurrency" of the Computer Science and Engineering degree of our University. The main goal of this work is to have a tool that helps students learning the subject, so they can better understand the core concepts and correct common mistakes in the course practical work. We have implemented a library for visualizing concurrent Java programsusing a graphical notation similar to the one used in class, which supports the design of concurrent programs whose synchronization mechanisms are either monitors(using the Monitor package) or CSP(as implemented in the JCSP library from Kent University).

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Este trabajo de fin de grado trata sobre el estudio de la energía solar de concentración en todos sus aspectos. Se han analizado sus tecnologías, así como posibles innovaciones que se puedan producir en los próximos años. También se va ha llevado a cabo un estudio de los costes actuales que conlleva el uso de este tipo de generación de energía, así como un análisis de las reducciones que pueden experimentar estos costes. Para poder realizar una comparación posterior con la energía solar fotovoltaica se ha escrito un capítulo dedicado exclusivamente a esta tecnología para conocer cuál es el estado actual. Además se ha realizado un análisis DAFO de los mercados que a priori puedan parecer más beneficiosos y que cuenten con un mayor potencial para el desarrollo de esta tecnología. A modo de conclusión para exponer la comparativa entre esta tecnología y la energía solar fotovoltaica se ha desarrollado un análisis de la viabilidad económica de dos plantas de estas tecnologías para comprobar en qué escenarios resulta más provechosa cada una de ellas. Al final se incluyen unas conclusiones extraídas del desarrollo del trabajo. Abstract This project concerns a study about every aspect about the concentrated solar power. Each type of technology has been analyzed as well as the possible innovations that may occur in the future. Also, the theme regarding the costs of this kind of power generation and an analysis dealing with the potential cost reduction that it may experience has been carried out. Then, in anticipation to do a comparative with the photovoltaic solar power, a whole chapter has been dedicated to this technology, to know what its actual state is. In addition, a SWOT analysis has also been carried out about the countries that at first sight might be a good option to develop the CSP. To conclude and to expose the comparative between these two technologies, a study about the economic viability of two power plants to know under what circumstances are each of them more profitable has been made. At the end some conclusions extracted from the development of this work have been included.