994 resultados para one-pass tableau


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Therapeutic approaches to chronic actinic cheilitis focus on the removal or destruction of diseased epithelium. The CO(2) laser has become an important therapeutic alternative, achieving clinical resolution in around 90% of patients. Although many laser physical parameters have been reported, some are known for their low potential for scar induction without compromising the success of the results. The aim of this clinicohistological study was to compare the therapeutic responses to two low-morbidity protocols involving a single laser pass. A total of 40 patients with chronic multicentric and microscopically proven disease were randomly submitted to two conservative CO(2) laser protocols using a bilateral comparative model. The degree of histological atypia of the epithelium was determined in 26 patients both pre- and postoperatively for both protocols. Other histological phenomena were assessed in addition to this central analysis parameter. Clinical recurrence occurred in 12.5% of patients for each protocol, together with a significant reduction in the degree of epithelial atypia (p < 0.001), which was occasionally complete. However, no difference was found between the protocols (p > 0.05). Using these morphological parameters it was not possible to determine whether postoperative epithelial atypias in part of the sample were reactive or residual in nature. A few patients may show minor postoperative lesions. Due to their potential to achieve clinical and importantly microscopic resolution, the studied protocols may be used for mild through moderate dysplastic epithelium and clinically diffuse disease.

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Therapeutic approaches to chronic actinic cheilitis focus on the removal or destruction of diseased epithelium. The CO(2) laser has become an important therapeutic alternative, achieving clinical resolution in around 90% of patients. Although many laser physical parameters have been reported, some are known for their low potential for scar induction without compromising the success of the results. The aim of this clinicohistological study was to compare the therapeutic responses to two low-morbidity protocols involving a single laser pass. A total of 40 patients with chronic multicentric and microscopically proven disease were randomly submitted to two conservative CO(2) laser protocols using a bilateral comparative model. The degree of histological atypia of the epithelium was determined in 26 patients both pre- and postoperatively for both protocols. Other histological phenomena were assessed in addition to this central analysis parameter. Clinical recurrence occurred in 12.5% of patients for each protocol, together with a significant reduction in the degree of epithelial atypia (p < 0.001), which was occasionally complete. However, no difference was found between the protocols (p > 0.05). Using these morphological parameters it was not possible to determine whether postoperative epithelial atypias in part of the sample were reactive or residual in nature. A few patients may show minor postoperative lesions. Due to their potential to achieve clinical and importantly microscopic resolution, the studied protocols may be used for mild through moderate dysplastic epithelium and clinically diffuse disease.

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A niobium single crystal was subjected to equal channel angular pressing (ECAP) at room temperature after orienting the crystal such that [1 -1 -1] ayen ND, [0 1 -1] ayen ED, and [-2 -1 -1] ayen TD. Electron backscatter diffraction (EBSD) was used to characterize the microstructures both on the transverse and the longitudinal sections of the deformed sample. After one pass of ECAP the single crystal exhibits a group of homogeneously distributed large misorientation sheets and a well formed cell structure in the matrix. The traces of the large misorientation sheets match very well with the most favorably oriented slip plane and one of the slip directions is macroscopically aligned with the simple shear plane. The lattice rotation during deformation was quantitatively estimated through comparison of the orientations parallel to three macroscopic axes before and after deformation. An effort has been made to link the microstructure with the initial crystal orientation. Collinear slip systems are believed to be activated during deformation. The full constraints Taylor model was used to simulate the orientation evolution during ECAP. The result matched only partially with the experimental observation.

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We show that if performance measures in a stochastic scheduling problem satisfy a set of so-called partial conservation laws (PCL), which extend previously studied generalized conservation laws (GCL), then the problem is solved optimally by a priority-index policy for an appropriate range of linear performance objectives, where the optimal indices are computed by a one-pass adaptive-greedy algorithm, based on Klimov's. We further apply this framework to investigate the indexability property of restless bandits introduced by Whittle, obtaining the following results: (1) we identify a class of restless bandits (PCL-indexable) which are indexable; membership in this class is tested through a single run of the adaptive-greedy algorithm, which also computes the Whittle indices when the test is positive; this provides a tractable sufficient condition for indexability; (2) we further indentify the class of GCL-indexable bandits, which includes classical bandits, having the property that they are indexable under any linear reward objective. The analysis is based on the so-called achievable region method, as the results follow fromnew linear programming formulations for the problems investigated.

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Este estudo teve o objetivo de avaliar o impacto do tráfego de máquinas na qualidade física do solo e produtividade de milho em Argissolo. O delineamento experimental foi inteiramente casualizado, com seis tratamentos e oito repetições representadas por parcelas de 14 m². Os tratamentos foram: T0) sem tráfego; T1*) uma passada de trator de 3,0 t, uma ao lado da outra; T1) uma passada; T2) duas passadas; T4) quatro passadas; T8) oito passadas de um trator de 8,0 t. Utilizou-se o milho (Zea mays L.) híbrido master, que foi avaliado quanto à produtividade de grãos. No solo, foram avaliados a porosidade, a densidade do solo, a resistência à penetração, o intervalo hídrico ótimo e a densidade do solo relativa. O tráfego de máquinas compactou o solo até 0,25 m de profundidade e reduziu a produtividade de milho em até 22%. O intervalo hídrico ótimo diminuiu com o aumento do tráfego de máquinas indicando decréscimo da qualidade física do solo para o milho. A densidade do solo relativa limitante à produtividade de milho é de 0,89.

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The technical and economic viability of solar heating for swimming pools is unquestionable, besides there it replaces the high costs and environmental impacts of conventional supply of energy, and it improves an optimization in the pool heating uses. This work applies the principles of the greenhouse effect: advanced thermodynamics, heat retention and equalization of temperature, to optimize the solar heating equipment, reducing the area required by collectors as much as 40% (still estimated value) for commercial collectors, with minor architectural and aesthetic impacts on the environment. It features a solar heating alternative in pools, whose main characteristics: low cost, simplicity in manufacturing and assembly and a faster heating. The system consists of two collectors spiral hoses made of polyethylene with a hundred meters each, and working on a forced flow, with only one pass of the working fluid inside the coils, and is used to pump itself treatment of pool water to obtain the desired flow. One of the collectors will be exposed to direct solar radiation, and the other will be covered by a glass slide and closed laterally, so providing the greenhouse effect. The equipment will be installed in parallel and simultaneously exposed to the sun in order to obtain comparative data on their effectiveness. Will be presented results of thermal tests for this the two cases, with and without transparent cover. Will be demonstrated, by comparison, the thermal, economic and material feasibility of these systems for heating swimming pools.

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A thorough study of the thermal performance of multipass parallel cross-flow and counter-cross-flow heat exchangers has been carried out by applying a new numerical procedure. According to this procedure, the heat exchanger is discretized into small elements following the tube-side fluid circuits. Each element is itself a one-pass mixed-unmixed cross-flow heat exchanger. Simulated results have been validated through comparisons to results from analytical solutions for one- to four-pass, parallel cross-flow and counter-cross-flow arrangements. Very accurate results have been obtained over wide ranges of NTU (number of transfer units) and C* (heat capacity rate ratio) values. New effectiveness data for the aforementioned configurations and a higher number of tube passes is presented along with data for a complex flow configuration proposed elsewhere. The proposed procedure constitutes a useful research tool both for theoretical and experimental studies of cross-flow heat exchangers thermal performance.

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A new numerical methodology for thermal performance calculation in cross-flow heat exchangers is developed. Effectiveness-number of transfer units (epsilon-NTU) data for several standard and complex flow arrangements are obtained using this methodology. The results are validated through comparison with analytical solutions for one-pass cross-flow heat exchangers with one to four rows and with approximate series solution for an unmixed-unmixed heat exchanger, obtaining in all cases very small errors. New effectiveness data for some complex configurations are provided. (c) 2005 Elsevier Ltd. All rights reserved.

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Whereas genome sequencing defines the genetic potential of an organism, transcript sequencing defines the utilization of this potential and links the genome with most areas of biology. To exploit the information within the human genome in the fight against cancer, we have deposited some two million expressed sequence tags (ESTs) from human tumors and their corresponding normal tissues in the public databases. The data currently define approximate to23,500 genes, of which only approximate to1,250 are still represented only by ESTs. Examination of the EST coverage of known cancer-related (CR) genes reveals that <1% do not have corresponding ESTs, indicating that the representation of genes associated with commonly studied tumors is high. The careful recording of the origin of all ESTs we have produced has enabled detailed definition of where the genes they represent are expressed in the human body. More than 100,000 ESTs are available for seven tissues, indicating a surprising variability of gene usage that has led to the discovery of a significant number of genes with restricted expression, and that may thus be therapeutically useful. The ESTs also reveal novel nonsynonymous germline variants (although the one-pass nature of the data necessitates careful validation) and many alternatively spliced transcripts. Although widely exploited by the scientific community, vindicating our totally open source policy, the EST data generated still provide extensive information that remains to be systematically explored, and that may further facilitate progress toward both the understanding and treatment of human cancers.

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Visual analysis of social networks is usually based on graph drawing algorithms and tools. However, social networks are a special kind of graph in the sense that interpretation of displayed relationships is heavily dependent on context. Context, in its turn, is given by attributes associated with graph elements, such as individual nodes, edges, and groups of edges, as well as by the nature of the connections between individuals. In most systems, attributes of individuals and communities are not taken into consideration during graph layout, except to derive weights for force-based placement strategies. This paper proposes a set of novel tools for displaying and exploring social networks based on attribute and connectivity mappings. These properties are employed to layout nodes on the plane via multidimensional projection techniques. For the attribute mapping, we show that node proximity in the layout corresponds to similarity in attribute, leading to easiness in locating similar groups of nodes. The projection based on connectivity yields an initial placement that forgoes force-based or graph analysis algorithm, reaching a meaningful layout in one pass. When a force algorithm is then applied to this initial mapping, the final layout presents better properties than conventional force-based approaches. Numerical evaluations show a number of advantages of pre-mapping points via projections. User evaluation demonstrates that these tools promote ease of manipulation as well as fast identification of concepts and associations which cannot be easily expressed by conventional graph visualization alone. In order to allow better space usage for complex networks, a graph mapping on the surface of a sphere is also implemented.

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La pataca (Helianthus tuberosus L.) es una especie de cultivo con un alto potencial en la producción de hidratos de carbono de reserva en forma de polifructanos, especialmente inulina, que se acumulan temporalmente en los tallos en forma de polisacáridos para translocarse posteriormente a los tubérculos, donde son almacenados. Aunque tradicionalmente el producto de interés del cultivo son los tubérculos, que acumulan gran cantidad de hidratos de carbono fermentables (HCF) cuando se recogen al final del ciclo de desarrollo, en este trabajo se pretende evaluar el potencial de la pataca como productor de HCF a partir de los tallos cosechados en el momento de máximo contenido en HCF, mediante un sistema de cultivo plurianual. Se han realizado los siguientes estudios: i) Determinación del momento óptimo de cosecha en ensayos con 12 clones ii) Potencial del cultivo plurianual de la pataca en términos de producción anual de biomasa aérea y de HCF en cosechas sucesivas, iii) Ensayos de conservación de la biomasa aérea, iv) Estimación de los costes de las dos modalidades de cultivo de pataca para producción de HCF y v) Estimación de la sostenibilidad energética de la producción de bioetanol mediante la utilización de los subproductos. Para la determinación del momento óptimo de la cosecha de la biomasa aérea se ensayaron 12 clones de diferente precocidad en Madrid; 4 tempranos (Huertos de Moya, C-17, Columbia y D-19) y 8 tardíos (Boniches, China, K-8, Salmantina, Nahodka, C-13, INIA y Violeta de Rennes). El máximo contenido en HCF tuvo lugar en el estado fenológico de botón floral-flor que además coincidió con la máxima producción de biomasa aérea. De acuerdo con los resultados obtenidos, la cosecha de los clones tempranos se debería realizar en el mes de julio y en los clones tardíos en septiembre, siendo éstos últimos más productivos. La producción media más representativa entre los 12 clones, obtenida en el estado fenológico de botón floral fue de 23,40 t ms/ha (clon INIA), con un contenido medio en HCF de 30,30 % lo que supondría una producción potencial media de 7,06 t HCF/ha. La producción máxima en HCF se obtuvo en el clon Boniches con 7,61 t/ha y 22,81 t ms/ha de biomasa aérea. En el sistema de cultivo plurianual la cantidad de tallos por unidad de superficie aumenta cada año debido a la cantidad de tubérculos que van quedando en el terreno, sobre todo a partir del 3er año, lo que produce la disminución del peso unitario de los tallos, con el consiguiente riesgo de encamado. El aclareo de los tallos nacidos a principios de primavera mediante herbicidas tipo Glifosato o mediante una labor de rotocultor rebaja la densidad final de tallos y mejora los rendimientos del cultivo. En las experiencias de conservación de la biomasa aérea se obtuvo una buena conservación por un período de 6 meses de los HCF contenidos en los tallos secos empacados y almacenados bajo cubierta. Considerando que el rendimiento práctico de la fermentación alcohólica es de 0,5 l de etanol por cada kg de azúcar, la producción potencial de etanol para una cosecha de tallos de 7,06 t de HCF/ha sería de 3.530 l/ha. El bagazo producido en la extracción de los HCF de la biomasa aérea supondría 11,91 t/ha lo que utilizado para fines térmicos supone más de 3 veces la energía primaria requerida en el proceso de producción de etanol, considerando un poder calorífico inferior de 3.832,6 kcal/kg. Para una producción de HCF a partir de la biomasa aérea de 7,06 t/ha y en tubérculos al final del ciclo de 12,11 t/ha, los costes de producción estimados para cada uno de ellos fueron de 184,69 €/t para los HCF procedentes de la biomasa aérea y 311,30 €/t para los de tubérculos. Como resultado de este trabajo se puede concluir que la producción de HCF a partir de la biomasa aérea de pataca en cultivo plurianual, es viable desde un punto de vista técnico, con reducción de los costes de producción respecto al sistema tradicional de cosecha de tubérculos. Entre las ventajas técnicas de esta modalidad de cultivo, cabe destacar: la reducción de operaciones de cultivo, la facilidad y menor coste de la cosecha, y la posibilidad de conservación de los HCF en la biomasa cosechada sin mermas durante varios meses. Estas ventajas, compensan con creces el menor rendimiento por unidad de superficie que se obtiene con este sistema de cultivo frente al de cosecha de los tubérculos. Jerusalem artichoke (Helianthus tuberosus L.) (JA) is a crop with a high potential for the production of carbohydrates in the form of polyfructans, especially inulin, which are temporarily accumulated in the stems in the form of polysaccharides. Subsequently they are translocated to the tubers, where they are finally accumulated. In this work the potential of Jerusalem artichoke for fermentable carbohydrates from stems that are harvested at their peak of carbohydrates accumulation is assessed as compared to the traditional cultivation system that aims at the production of tubers harvested at the end of the growth cycle. Tubers are storage organs of polyfructans, namely fermentable carbohydrates. Studies addressed in this work were: i) Determination of the optimum period of time for stem harvesting as a function of clone precocity in a 12-clone field experiment; ii) Study of the potential of JA poly-annual crop regarding the annual yield of aerial biomass and fermentable carbohydrates (HCF) over the years; iii) Tests of storage of the aerial biomass, iv) Comparative analysis of the two JA cultivation systems for HCF production: the poly-annual system for aerial biomass harvesting versus the annual cultivation system for tubers and v) Estimation of the energy sustainability of the bioethanol production by using by-products of the production chain. In order to determine the best period of time for aerial biomass harvesting twelve JA clones of different precocity were tested in Madrid: four early clones (Huertos de Moya, C-17, Columbia and D-19) and eight late clones (Boniches, China, K-8 , Salmantina, Nahodka, C-13, INIA and Violeta de Rennes). Best time was between the phenological stages of floral buds (closed capitula) and blossom (opened capitula), period in which the peak of biomass production coincides with the peak of HCF accumulation in the stems. According to the results, the early clones should be harvested in July and the late ones in September, being the late clones more productive. The clone named INIA was the one that exhibited more steady yields in biomass over the 12 clones experimented. The average potential biomass production of this clone was 23.40 t dm/ha when harvested at the floral buds phenological stage; mean HCF content is 30.30%, representing 7.06 t HCF/ha yield. However, the highest HCF production was obtained for the clone Boniches, 7.61 t HCF/ha from a production of 22.81 t aerial biomass/ha. In the poly-annual cultivation system the number of stems per unit area increases over the years due to the increase in the number of tubers that are left under ground; this effect is particularly important after the 3rd year of the poly-annual crop and results in a decrease of the stems unit weight and a risk of lodging. Thinning of JA shoots in early spring, by means of an herbicide treatment based on glyphosate or by means of one pass with a rotary tiller, results in a decrease of the crop stem density and in higher crop yields. Tests of biomass storing showed that the method of keeping dried stems packed and stored under cover results in a good preservation of HCF for a period of six months at least. Assuming that the fermentation yield is 0.5 L ethanol per kg sugars and a HCF stem production of 7.06 t HCF/ha, the potential for bioethanol is estimated at 3530 L/ha. The use of bagasse -by-product of the process of HCF extraction from the JA stems- for thermal purposes would represent over 3 times the primary energy required for the industrial ethanol production process, assuming 11.91 t/ha bagasse and 3832.6 kcal/kg heating value. HCF production costs of 7.06 t HCF/ha yield from aerial biomass and HCF production costs of 12.11 t HCF/ha from tubers were estimated at 184.69 €/t HCF and 311.30 €/t HCF, respectively. It can be concluded that the production of HCF from JA stems, following a poly-annual cultivation system, can be feasible from a technical standpoint and lead to lower production costs as compared to the traditional annual cultivation system for the production of HCF from tubers. Among the technical advantages of the poly-annual cultivation system it is worth mentioning the reduction in crop operations, the ease and efficiency of harvesting operations and the possibility of HCF preservation without incurring in HCF losses during the storage period, which can last several months. These advantages might compensate the lower yield of HCF per unit area that is obtained in the poly-annual crop system, which aims at stems harvesting, versus the annual one, which involves tubers harvesting.

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This paper presents a technique for achieving a class of optimizations related to the reduction of checks within cycles. The technique uses both Program Transformation and Abstract Interpretation. After a ñrst pass of an abstract interpreter which detects simple invariants, program transformation is used to build a hypothetical situation that simpliñes some predicates that should be executed within the cycle. This transformation implements the heuristic hypothesis that once conditional tests hold they may continué doing so recursively. Specialized versions of predicates are generated to detect and exploit those cases in which the invariance may hold. Abstract interpretation is then used again to verify the truth of such hypotheses and conñrm the proposed simpliñcation. This allows optimizations that go beyond those possible with only one pass of the abstract interpreter over the original program, as is normally the case. It also allows selective program specialization using a standard abstract interpreter not speciñcally designed for this purpose, thus simplifying the design of this already complex module of the compiler. In the paper, a class of programs amenable to such optimization is presented, along with some examples and an evaluation of the proposed techniques in some application áreas such as floundering detection and reducing run-time tests in automatic logic program parallelization. The analysis of the examples presented has been performed automatically by an implementation of the technique using existing abstract interpretation and program transformation tools.

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To discover genes involved in von Hippel-Lindau (VHL)-mediated carcinogenesis, we used renal cell carcinoma cell lines stably transfected with wild-type VHL-expressing transgenes. Large-scale RNA differential display technology applied to these cell lines identified several differentially expressed genes, including an alpha carbonic anhydrase gene, termed CA12. The deduced protein sequence was classified as a one-pass transmembrane CA possessing an apparently intact catalytic domain in the extracellular CA module. Reintroduced wild-type VHL strongly inhibited the overexpression of the CA12 gene in the parental renal cell carcinoma cell lines. Similar results were obtained with CA9, encoding another transmembrane CA with an intact catalytic domain. Although both domains of the VHL protein contribute to regulation of CA12 expression, the elongin binding domain alone could effectively regulate CA9 expression. We mapped CA12 and CA9 loci to chromosome bands 15q22 and 17q21.2 respectively, regions prone to amplification in some human cancers. Additional experiments are needed to define the role of CA IX and CA XII enzymes in the regulation of pH in the extracellular microenvironment and its potential impact on cancer cell growth.

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FULL-malaria is a database for a full-length-enriched cDNA library from the human malaria parasite Plasmodium falciparum (http://133.11.149.55/). Because of its medical importance, this organism is the first target for genome sequencing of a eukaryotic pathogen; the sequences of two of its 14 chromosomes have already been determined. However, for the full exploitation of this rapidly accumulating information, correct identification of the genes and study of their expression are essential. Using the oligo-capping method, we have produced a full-length-enriched cDNA library from erythrocytic stage parasites and performed one-pass reading. The database consists of nucleotide sequences of 2490 random clones that include 390 (16%) known malaria genes according to BLASTN analysis of the nr-nt database in GenBank; these represent 98 genes, and the clones for 48 of these genes contain the complete protein-coding sequence (49%). On the other hand, comparisons with the complete chromosome 2 sequence revealed that 35 of 210 predicted genes are expressed, and in addition led to detection of three new gene candidates that were not previously known. In total, 19 of these 38 clones (50%) were full-length. From these obser­vations, it is expected that the database contains ∼1000 genes, including 500 full-length clones. It should be an invaluable resource for the development of vaccines and novel drugs.

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In many online applications, we need to maintain quantile statistics for a sliding window on a data stream. The sliding windows in natural form are defined as the most recent N data items. In this paper, we study the problem of estimating quantiles over other types of sliding windows. We present a uniform framework to process quantile queries for time constrained and filter based sliding windows. Our algorithm makes one pass on the data stream and maintains an E-approximate summary. It uses O((1)/(epsilon2) log(2) epsilonN) space where N is the number of data items in the window. We extend this framework to further process generalized constrained sliding window queries and proved that our technique is applicable for flexible window settings. Our performance study indicates that the space required in practice is much less than the given theoretical bound and the algorithm supports high speed data streams.