643 resultados para Pic pétrolier


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∗The author supported by Contract NSFR MM 402/1994.

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The coccolithophore Emiliania huxleyi was cultured under a broad range of carbonate chemistry conditions to distinguish the effects of individual carbonate system parameters on growth, primary production, and calcification. In the first experiment, alkalinity was kept constant and the fugacity of CO2(fCO2) varied from 2 to 600 Pa (1Pa ~ 10 µatm). In the second experiment, pH was kept constant (pHfree = 8) with fCO2 varying from 4 to 370 Pa. Results of the constant-alkalinity approach revealed physiological optima for growth, calcification, and organic carbon production at fCO2 values of ~20Pa, ~40 Pa, and ~80 Pa, respectively. Comparing this with the constant-pH approach showed that growth and organic carbon production increased similarly from low to intermediate CO2 levels but started to diverge towards higher CO2 levels. In the high CO2 range, growth rates and organic carbon production decreased steadily with declining pH at constant alkalinity while remaining consistently higher at constant pH. This suggests that growth and organic carbon production rates are directly related to CO2 at low (sub-saturating) concentrations, whereas towards higher CO2 levels they are adversely affected by the associated decrease in pH. A pH dependence at high fCO2 is also indicated for calcification rates, while the key carbonate system parameter determining calcification at low fCO2 remains unclear. These results imply that key metabolic processes in coccolithophores have their optima at different carbonate chemistry conditions and are influenced by different parameters of the carbonate system at both sides of the optimum.

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Modèle d’équilibre général calculable

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El objetivo de este libro es enseñar los principios fundamentales para la programación de los microcontroladores, tomando como base los microcontroladores PIC de Microchip. El texto está organizado en tres partes. La primera parte está fundamentada en los principios teóricos de la organización y su arquitectura; contiene las definiciones de las características generales de los procesadores, con énfasis en los recursos especiales del procesador, las funciones de cada uno de los bits, de sus registros, la organización de los mapas de memoria de programa y memoria de datos, el conjunto de instrucciones, sus puertos y sus principales periféricos. La segunda parte está orientada a las aplicaciones, y contiene las indicaciones para el manejo de las herramientas de desarrollo, programas de aplicación para la configuración y operación de sus puertos y aplicaciones para programar sus periféricos. Estas aplicaciones están desarrolladas con el lenguaje asembler o de bajo nivel y el lenguaje C. Estas dos opciones de programación dan la oportunidad al estudiante de aprender ambas técnicas y de escoger el lenguaje que más le convenga según sus necesidades. La tercera parte hace referencia a una sección de anexos que es un material de apoyo y consulta para el desarrollo de los programas que se presenta en el texto. El libro está dirigido especialmente a estudiantes y profesionales del campo de la electrónica y los sistemas.

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Desde los años 80’s, en los barrios populares de Cartagena y Barranquilla se ha venido desarrollando un fenómeno musical denominado champeta. Este tipo de música es descendiente de bailes populares conocidos en la tradición regional como casetas o verbenas, en los cuales el eje central son grandes amplificadores de sonido denominados picós y datan aproximadamente del decenio de 1950 del siglo XX . El presente trabajo se inscribe en los estudios sociales de la música en los que se analiza los procesos de creación, difusión y distribución por los que atraviesa una canción de champeta en la ciudad de Barranquilla, Caribe de Colombia. Teniendo en cuenta que dichos procesos responden a una lógica de circulación musical alternativa enmarcada en un contexto en el que la música champeta es marginada y estigmatizada por las élites costeñas y nacionales a través de varios mecanismos discursivos, legales y mediáticos, generando unas formas de circulación musical propias que colindan entre lo informal/ilegal.

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Public participate in the planning and design of major public infrastructure and construction (PIC) projects is crucial to their success, as the interests of different stakeholders can be systematically captured and built into the finalised scheme. However, public participation may not always yield a mutually acceptable solution, especially when the interests of stakeholders are diverse and conflicting. Confrontations and disputes can arise unless the concerns or needs of the community are carefully analysed and addressed. The aim of the paper is to propose a systematic method of analysing stakeholder concerns relating to PIC projects by examining the degree of consensus and/or conflict involved. The results of a questionnaire survey and a series of interviews with different entities are provided, which indicate the existence of a significant divergence of views among stakeholder groups and that conflicts arise when there is a mismatch between peoples’ perception concerning money and happiness on the one hand and development and damages on the other. Policy and decision-makers should strive to resolve at least the majority of conflicts that arise throughout the lifecycle of major PIC projects so as to maximise their chance of success.

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Many governments world-wide are increasingly encouraging the involvement of interested individuals, groups and organisations in their publicinfrastructure and construction (PIC) projects as a means of improving the openness, transparency and accountability of the decision-making process and help improve the projects’ long-term viability and benefits to the community. In China, however, the current participatory mechanism at the project level exists only as part of the environmental impact assessment (EIA) process. With an increasing demand for PIC projects and social equality in China, this suggests a need to bring the participatory process into line with international practice. The aim of this paper, therefore, is to identify the weaknesses of EIA-basedpublicparticipation in China and the means by which it may be improved for the whole lifecycle of PIC schemes. To do this, the results of a series of interviews with a diverse group of experts is reported which analyse the nature and extent of existing problems of publicparticipation in EIA and suggestions for improvement. These indicate that the current level of participation in PIC projects is quite limited, particularly in the crucial earlier stages, primarily due to traditional culture and values, uneven progress in the adoption of participatory mechanisms, the risk of not meeting targets and lack of confidence in public competence. Finally, aprocess flowchart is proposed to guide construction practitioners and the community in general.

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The common focus of the studies brought together in this work is the prosodic segmentation of spontaneous speech. The theoretically most central aspect is the introduction and further development of the IJ-model of intonational chunking. The study consists of a general introduction and five detailed studies that approach prosodic chunking from different perspectives. The data consist of recordings of face-to-face interaction in several spoken varieties of Finnish and Finland Swedish; the methodology is usage-based and qualitative. The term “speech prosody” refers primarily to the melodic and rhythmic characteristics of speech. Both speaking and understanding speech require the ability to segment the flow of speech into suitably sized prosodic chunks. In order to be usage-based, a study of spontaneous speech consequently needs to be based on material that is segmented into prosodic chunks of various sizes. The segmentation is seen to form a hierarchy of chunking. The prosodic models that have so far been developed and employed in Finland have been based on sentences read aloud, which has made it difficult to apply these models in the analysis of spontaneous speech. The prosodic segmentation of spontaneous speech has not previously been studied in detail in Finland. This research focuses mainly on the following three questions: (1) What are the factors that need to be considered when developing a model of prosodic segmentation of speech, so that the model can be employed regardless of the language or dialect under analysis? (2) What are the characteristics of a prosodic chunk, and what are the similarities in the ways chunks of different languages and varieties manifest themselves that will make it possible to analyze different data according to the same criteria? (3) How does the IJ-model of intonational chunking introduced as a solution to question (1) function in practice in the study of different varieties of Finnish and Finland Swedish? The boundaries of the prosodic chunks were manually marked in the material according to context-specific acoustic and auditory criteria. On the basis of the data analyzed, the IJ-model was further elaborated and implemented, thus allowing comparisons between different language varieties. On the basis of the empirical comparisons, a prosodic typology is presented for the dialects of Swedish in Finland. The general contention is that the principles of the IJ-model can readily be used as a methodological tool for prosodic analysis irrespective of language varieties.

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Background: Cultivated peanut or groundnut (Arachis hypogaea L.) is the fourth most important oilseed crop in the world, grown mainly in tropical, subtropical and warm temperate climates. Due to its origin through a single and recent polyploidization event, followed by successive selection during breeding efforts, cultivated groundnut has a limited genetic background. In such species, microsatellite or simple sequence repeat (SSR) markers are very informative and useful for breeding applications. The low level of polymorphism in cultivated germplasm, however, warrants a need of larger number of polymorphic microsatellite markers for cultivated groundnut. Results: A microsatellite- enriched library was constructed from the genotype TMV2. Sequencing of 720 putative SSR-positive clones from a total of 3,072 provided 490 SSRs. 71.2% of these SSRs were perfect type, 13.1% were imperfect and 15.7% were compound. Among these SSRs, the GT/CA repeat motifs were the most common (37.6%) followed by GA/CT repeat motifs (25.9%). The primer pairs could be designed for a total of 170 SSRs and were optimized initially on two genotypes. 104 (61.2%) primer pairs yielded scorable amplicon and 46 (44.2%) primers showed polymorphism among 32 cultivated groundnut genotypes. The polymorphic SSR markers detected 2 to 5 alleles with an average of 2.44 per locus. The polymorphic information content (PIC) value for these markers varied from 0.12 to 0.75 with an average of 0.46. Based on 112 alleles obtained by 46 markers, a phenogram was constructed to understand the relationships among the 32 genotypes. Majority of the genotypes representing subspecies hypogaea were grouped together in one cluster, while the genotypes belonging to subspecies fastigiata were grouped mainly under two clusters. Conclusion. Newly developed set of 104 markers extends the repertoire of SSR markers for cultivated groundnut. These markers showed a good level of PIC value in cultivated germplasm and therefore would be very useful for germplasm analysis, linkage mapping, diversity studies and phylogenetic relationships in cultivated groundnut as well as related Arachis species.

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Cultivated groundnut (Arachis hypogaea L.) is an agronomically and economically important oilseed crop grown extensively throughout the semi-arid tropics of Asia, Africa and Latin America. Rust (Puccinia arachidis) and late leaf spot (LLS, Phaseoisariopsis personata) are among the major diseases causing significant yield loss in groundnut. The development of varieties with high levels of resistance has been constrained by adaptation of disease isolates to resistance sources and incomplete resistance in resistant sources. Despite the wide range of morphological diversity observed in the cultivated groundnut gene pool, molecular marker analyses have thus far been unable to detect a parallel level of genetic diversity. However, the recent development of simple sequence repeat (SSR) markers presents new opportunities for molecular diversity analysis of cultivate groundnut. The current study was conducted to identify diverse disease resistant germplasm for the development of mapping populations and for their introduction into breeding programs. Twenty-three SSRs were screened across 22 groundnut genotypes with differing levels of resistance to rust and LLS. Overall, 135 alleles across 23 loci were observed in the 22 genotypes screened. Twelve of the 23 SSRs (52%) showed a high level of polymorphism, with PIC values ≥0.5. This is the first report detecting such high levels of genetic polymorphism in cultivated groundnut. Multi-dimensional scaling and cluster analyses revealed three well-separated groups of genotypes. Locus by locus AMOVA and Kruskal-Wallis one-way ANOVA identified candidate SSR loci that may be valuable for mapping rust and LLS resistance. The molecular diversity analysis presented here provides valuable information for groundnut breeders designing strategies for incorporating and pyramiding rust and late leaf spot resistances and for molecular biologists wishing to create recombinant inbred line populations to map these traits.

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New complexes of lanthanide nitrates with 2-N-(6-picolyl)-benzamide of the formulae Ln2[6-pic-BA], [NO3l6 (Ln = Y and La-Yb) have been prepared and characterised by chemical analysis, infrared, molar conductance and electronic spectral data. Molar conductance data along with IR data point to the presence of co-ordinated nitrate groups. IR spectra prove the bidentate co-ordination of the ligand to the metal ion, through the oxygen of the secondary amide and the nitrogen of the heterocyclic ring. Electronic spectral studies in the visible region suggest an eight co-ordinate geometry around the metal ions.

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The following synonymies are proposed based on examination of primary types (lectotypes are designated for all taxa except those marked with a '*'): Lemidia spinnipennis Lea, 1907 syn. n. and Lemidia bicolor Schenkling, 1906 syn. n. = Lemidia biaculeata (Westwood); Lemidia mastersi Lea, 1907 syn. n. = Lemidia circumcincta Schenkling, 1906; Lemidia albonotata Pic, 1941 syn. n. = Lemidia laticeps Lea, 1907; Lemidia australiae Lea, 1907 syn. n. = Lemidia maculata Schenkling, 1902; Lemidia bilineatra Lea, 1907 syn. n. = Lemidia maculicollis Gorham, 1877; Lemidia decolor Pic, 1941 syn. n. = Lemidia munda Blackburn, 1892; *Phlogistus conspiciendus Elston, 1926 syn. n. = Mimolesterus ventralis (Westwood); Thanasimus cursorius Westwood, 1853 syn. n. and Stigmatium dispar Kuwert, 1894 syn. n. = Stigmatium acerbum (Newman); Stigmatium fasciatoventre Chevrolat, 1874 syn. n., Stigmatium flavescens Chevrolat, 1874 syn. n. and *Xestonotus eximius Kuwert, 1894 syn. n. = Stigmatium laevium Macleay, 1872; Stigmatium versipelle Gorham, 1876 syn. n. and Xestonotus (Cyclotomocerus) australicus Kuwert, 1894 syn. n. = Stigmatium varipes Chevrolat, 1876; Tarsostenus pulcher Macleay, 1872 syn. n. = *Tarsostenus carus (Newman, 1840). The available name Tarsosternus pulcher Macleay, 1872 is deemed a lapsus calami and emended to Tarsostenus pulcher Macleay, 1872.

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In continuation of our work on the effect of the anion on the coordination chemistry of the rare-earth metal ions, we have now extended our studies to 4-picoline-N-oxide (4-Pie NO) complexes of rare-earth bromides. By ohangi~ the method of preparation Harrison and Watsom (1) have prepared two types of Sm(IIl) complexes and three types of Eu(III) complexes of 4-pioollne-N-Oxide in the presence of perchlorate ions. We have isolated two types of pyridine-N-Oxide complexes of rare-earth bromides, also by changing the method of preparation (2). The effect of the change of the preparative method on the composition of the lanthanide complexes is exhibited in the case of other complexes also (3-6). But our attempts to prepare 4-picoline-N-Oxide of rare-earth bromides having different stoichiometries were unsucessful . The composition of the complexes is the same for all the complexes prepared. The results of the physico-chemical studies on these 4-Pic NO complexes of rare-earth bromides are discussed in the present paper.

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Let X be a normal projective threefold over a field of characteristic zero and vertical bar L vertical bar be a base-point free, ample linear system on X. Under suitable hypotheses on (X, vertical bar L vertical bar), we prove that for a very general member Y is an element of vertical bar L vertical bar, the restriction map on divisor class groups Cl(X) -> Cl(Y) is an isomorphism. In particular, we are able to recover the classical Noether-Lefschetz theorem, that a very general hypersurface X subset of P-C(3) of degree >= 4 has Pic(X) congruent to Z.