847 resultados para Approach to written


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The key parameters associated to the thermally induced spin crossover process have been calculated for a series of Fe(II) complexes with mono-, bi-, and tridentate ligands. Combination of density functional theory calculations for the geometries and for normal vibrational modes, and highly correlated wave function methods for the energies, allows us to accurately compute the entropy variation associated to the spin transition and the zero-point corrected energy difference between the low- and high-spin states. From these values, the transition temperature, T 1/2, is estimated for different compounds.

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The osteoporosis of the child and the teenager is a pathological reality; its multifactorial pathogenesis often requires a collaborative approach and multidisciplinary. The osteoporosis characterized by a reduction in the bone mineral density is not a uniform pathology; it must be dealt with on all the levels by analyzing the factors of risks, by giving itself the diagnostic means and while insisting on the importance of a preventive approach as well as therapeutic.

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A new approach to the synthesis of 4,5-disubstituted cyclopentenones is described. The strategy is based on the Pauson-Khand (PK) reaction of norbornadiene and N-Boc-propargylamine as alkyne with a masked leaving group, which can be eliminated at will. This approach to the synthesis of 4,5-disubstituted cyclopentenones overcomes the problem of using the alkylation to introduce the alpha-side-chain. As an example, prostane 13-epi-12-oxo-phytodienoic acid (13-epi-12-oxo-PDA) methyl ester was synthesized.

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The production and use of false identity and travel documents in organized crime represent a serious and evolving threat. However, a case-by-case perspective, thus suffering from linkage blindness and a limited analysis capacity, essentially drives the present-day fight against this criminal problem. To assist in overcoming these limitations, a process model was developed using a forensic perspective. It guides the systematic analysis and management of seized false documents to generate forensic intelligence that supports strategic and tactical decision-making in an intelligence-led policing approach. The model is articulated on a three-level architecture that aims to assist in detecting and following-up on general trends, production methods and links between cases or series. Using analyses of a large dataset of counterfeit and forged identity and travel documents, it is possible to illustrate the model, its three levels and their contribution. Examples will point out how the proposed approach assists in detecting emerging trends, in evaluating the black market's degree of structure, in uncovering criminal networks, in monitoring the quality of false documents, and in identifying their weaknesses to orient the conception of more secured travel and identity documents. The process model proposed is thought to have a general application in forensic science and can readily be transposed to other fields of study.

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Clinical practice guidelines have become an important source of information to support clinicians in the management of individual patients. However, current guideline methods have limitations that include the lack of separating the quality of evidence from the strength of recommendations. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) working group, an international collaboration of guideline developers, methodologists, and clinicians have developed a system that addresses these shortcomings. Core elements include transparent methodology for grading the quality of evidence, the distinction between quality of the evidence and strength of a recommendation, an explicit balancing of benefits and harms of health care interventions, an explicit recognition of the values and preferences that underlie recommendations. The GRADE system has been piloted in various practice settings to ensure that it captures the complexity involved in evidence assessment and grading recommendations while maintaining simplicity and practicality. Many guideline organizations and medical societies have endorsed the system and adopted it for their guideline processes.

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Työn tavoitteena on selvittää mitkä ovat tärkeimmät aineettomat resurssit, joita tarvitaan teollisuuksien risteyskohdassa tapahtuvassa tuotekehityksessä. Teollisuuksien risteyskohdissa syntyvät tuotteet ovat usein radikaaleja, mikä tekee tuotteista mielenkiintoisia, paljon liiketoimintapotentiaalia tarjoavia. Tämä tutkimus lähestyy tuotekehitystä resurssipohjaisesta näkökulmasta. Myös tietämyspohjaista ja suhdepohjaista näkemystä hyödynnetään korostamaan keskittymistä aineettomiin resursseihin. Tutkimuksessa rakennetaan viitekehys, jossa tutkitaan eri resurssikategorioita. Valitut kategoriat ovat teknologiset, markkinointi-, johtamiseen ja hallinnointiin liittyvät ja suhdepohjaiset resurssit. Empiirisessä osassa tutkitaan kahta uutta tuotekonseptia, jotka ovat syntyneet teollisuuksien risteyskohdissa. Empiirisen osan tavoitteena on määritellä tutkimuksen kohteena olevia alustavia tuotekonsepteja tarkemmin ja selvittää millaisia resursseja näiden toteuttamiseen tarvitaan. Myös tarvittavien resurssien nykytila selvitetään ja pohditaan tulisiko puuttuvia resursseja kehittää yrityksen sisällä vai hankkia ne ulkopuolelta. Tutkimus toteutettiin asiantuntijahaastatteluin. Kahden tapaustutkimuksen perusteella näyttäisi siltä, että suhdepohjaiset resurssit ovat erittäin tärkeitä teollisuuksien risteyskohdissa tapahtuvassa tuotekehityksessä. Myös teknologiset resurssit ovat tärkeitä. Markkinointiresurssien tärkeys riippuu lopullisesta tuotekonseptista, kun taas johtamiseen ja kehittämiseen liittyvät resurssit ovat tärkeitänäiden konseptien luomisessa.

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BACKGROUND: Developing and updating high-quality guidelines requires substantial time and resources. To reduce duplication of effort and enhance efficiency, we developed a process for guideline adaptation and assessed initial perceptions of its feasibility and usefulness. METHODS: Based on preliminary developments and empirical studies, a series of meetings with guideline experts were organised to define a process for guideline adaptation (ADAPTE) and to develop a manual and a toolkit made available on a website (http://www.adapte.org). Potential users, guideline developers and implementers, were invited to register and to complete a questionnaire evaluating their perception about the proposed process. RESULTS: The ADAPTE process consists of three phases (set-up, adaptation, finalisation), 9 modules and 24 steps. The adaptation phase involves identifying specific clinical questions, searching for, retrieving and assessing available guidelines, and preparing the draft adapted guideline. Among 330 registered individuals (46 countries), 144 completed the questionnaire. A majority found the ADAPTE process clear (78%), comprehensive (69%) and feasible (60%), and the manual useful (79%). However, 21% found the ADAPTE process complex. 44% feared that they will not find appropriate and high-quality source guidelines. DISCUSSION: A comprehensive framework for guideline adaptation has been developed to meet the challenges of timely guideline development and implementation. The ADAPTE process generated important interest among guideline developers and implementers. The majority perceived the ADAPTE process to be feasible, useful and leading to improved methodological rigour and guideline quality. However, some de novo development might be needed if no high quality guideline exists for a given topic.

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We present a new global method for the identification of hotspots in conservation and ecology. The method is based on the identification of spatial structure properties through cumulative relative frequency distributions curves, and is tested with two case studies, the identification of fish density hotspots and terrestrial vertebrate species diversity hotspots. Results from the frequency distribution method are compared with those from standard techniques among local, partially local and global methods. Our approach offers the main advantage to be independent from the selection of any threshold, neighborhood, or other parameter that affect most of the currently available methods for hotspot analysis. The two case studies show how such elements of arbitrariness of the traditional methods influence both size and location of the identified hotspots, and how this new global method can be used for a more objective selection of hotspots.

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The hydrological and biogeochemical processes that operate in catchments influence the ecological quality of freshwater systems through delivery of fine sediment, nutrients and organic matter. Most models that seek to characterise the delivery of diffuse pollutants from land to water are reductionist. The multitude of processes that are parameterised in such models to ensure generic applicability make them complex and difficult to test on available data. Here, we outline an alternative - data-driven - inverse approach. We apply SCIMAP, a parsimonious risk based model that has an explicit treatment of hydrological connectivity. we take a Bayesian approach to the inverse problem of determining the risk that must be assigned to different land uses in a catchment in order to explain the spatial patterns of measured in-stream nutrient concentrations. We apply the model to identify the key sources of nitrogen (N) and phosphorus (P) diffuse pollution risk in eleven UK catchments covering a range of landscapes. The model results show that: 1) some land use generates a consistently high or low risk of diffuse nutrient pollution; but 2) the risks associated with different land uses vary both between catchments and between nutrients; and 3) that the dominant sources of P and N risk in the catchment are often a function of the spatial configuration of land uses. Taken on a case-by-case basis, this type of inverse approach may be used to help prioritise the focus of interventions to reduce diffuse pollution risk for freshwater ecosystems. (C) 2012 Elsevier B.V. All rights reserved.

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RÉSUMÉ Le Grand tétras est un galliforme de montagne apparenté au faisan et au tétras lyre. Il est distribué de manière continue à travers la toundra et les montagnes de moyenne altitude en Europe de l'ouest. Toutefois, les populations d'Europe de l'ouest ont subi un déclin constant au cours des derniers siècles. Les causes de ce déclin sont probablement liées à l'activité humaine, telle .que l'élevage ou le tourisme, qui ont engendré une modification et une fragmentation de l'habitat de l'espèce. Malheureusement, les populations soumises à de forts déclins démographiques peuvent subir des effets génétiques (augmentation de la consanguinité et perte de diversité génétique) pouvant diminuer leur potentiel de reproduction et conduire irrémédiablement à l'extinction. Cette thèse présente les analyses conduites dans le but d'estimer l'impact du déclin démographique des populations de Grand tétras sur l'étendue et la distribution de leur variabilité génétique dans le Jura et dans les Pyrénées. Du fait de la législation locale protégeant les tétraonidés en général, mais également en raison de la biologie très cryptique du Grand tétras, l'ensemble des analyses de cette étude a été réalisé à partir de matériel génétique extrait des fientes (ou échantillonnage génétique non invasif). Dans la première partie de l'étude, je détaille les protocoles d'extraction. d'ADN et d'amplification par PCR modifiés à partir des protocoles classiques utilisant des échantillons conventionnels, riches en ADN. L'utilisation d'ADN fécal impose des contraintes dues à la mauvaise qualité et à la faible quantité du matériel génétique à disposition dans les fientes. Ces contraintes ont pu être partiellement contournées en réalisant des répétitions multiples du génotypage afin d'obtenir un degré de fiabilité suffisante. J'ai également analysé les causes de la dégradation de l'ADN dans les excréments. Parmi les causes les plus communes, telles que l'activité bactérienne, l'hydrolyse spontanée et la dégradation enzymatique par les DNases libres, c'est ce dernier facteur qui apparaît comme étant la cause majeure et la plus rapide responsable de la dégradation de la qualité des échantillons. La rapidité de l'action enzymatique suggère que les plans d'échantillonnages de excréments sur le terrain pourraient être optimisés en les réalisant dans des conditions climatiques froides et sèches, favorisant ainsi l'inhibition des DNases. La seconde partie de la thèse est une étude par simulation visant à déterminer la capacité du logiciel Structure à identifier les structures génétiques complexes et hiérarchiques fréquemment rencontrées dans les populations naturelles, et ce en utilisant différents types de marqueurs génétiques. Les troisième et quatrième parties de cette thèse décrivent le statut génétique des populations résiduelles du Jura et des Pyrénées à partir de l'analyse de 11 loci microsatellites. Nous n'avons pas pu mettre en évidence dans les deux populations des effets liés à la consanguinité ou à la réduction de la diversité génétique. De plus, la différenciation génétique entre les patches d'habitats favorables reste modérée et corrélée à la distance géographique, ce qui suggère que la dispersion d'individus entre les patches a été importante au moins pendant ces dernières générations. La comparaison des paramètres de la diversité génétique avec ceux d'autres populations de Grand tétras, ou d'autres espèces proches, indique que la population du Jura a retenu une proportion importante de sa diversité originelle. Ces résultats suggèrent que le déclin récent des populations a jusqu'ici eu un impact modéré sur les facteurs génétiques et que ces populations semblent avoir conservé le potentiel génétique nécessaire à leur survie à long terme. Finalement, en cinquième partie, l'analyse de l'apparentement entre les mâles qui participent à la parade sur les places de chant (leks) indique que ces derniers sont distribués en agrégats de manière non aléatoire, préférentiellement entre individus apparentés. De plus, la corrélation entre les distances génétique et géographique entre les leks est en accord avec les motifs d'isolement par la distance mis en évidence à d'autres niveaux hiérarchiques (entre patches d'habitat et populations), ainsi qu'avec les études menées sur d'autres espèces ayant choisi ce même système de reproduction. En conclusion, cette première étude basée uniquement sur de l'ADN nucléaire aviaire extrait à partir de fèces a fourni des informations nouvelles qui n'auraient pas pu être obtenues par une méthode d'observation sur le terrain ou d'échantillonnage génétique classique. Aucun oiseau n'a été dérangé ou capturé, et les résultats sont comparables à d'autres études concernant des espèces proches. Néanmoins, la taille de ces populations approche des niveaux au-dessous desquels la survie à long terme est fortement incertaine. La persistance de la diversité génétique pour les prochaines générations reste en conséquence liée à la survie des adultes et à une reprise du succès de la reproduction. ABSTRACT Capercaillie (Tetrao urogallus) is a large grouse that is continuously distributed across the tundra and the mid-high mountains of Western Europe. However, the populations in Western Europe have been showing a constant decline during the last decades. The causes for this decline are possibly related to human activities, such as cattle breeding and tourism that have both led to habitat modification and fragmentation. Unfortunately, populations that have undergone drastic demographic bottlenecks often go through genetic processes of inbreeding and loss of diversity that decrease their fitness and eventually lead to extinction. This thesis presents the investigations conducted to estimate the impact of the demographic decline of capercaillie populations on the extent and distribution of their genetic variability in the Jura and in the Pyrenees mountains. Because grouse are protected by wildlife legislation, and also because of the cryptic behaviour of capercaillie, all DNA material used in this study was extracted from faeces (non-invasive genetic sampling). In the first part of my thesis, I detail the protocols of DNA extraction and PCR amplification adapted from classical methods using conventional DNA-rich samples. The use of faecal DNA imposes specific constraints due to the low quantity and the highly degraded genetic material available. These constraints are partially overcome by performing multiple genotyping repetitions to obtain sufficient reliability. I also investigate the causes of DNA degradation in faeces. Among the main degraders, namely bacterial activity, spontaneous hydrolysis, and free-¬DNase activities, the latter was pointed out as the most important according to our experiments. These enzymes degrade DNA very rapidly, and, as a consequence, faeces sampling schemes must be planned preferably in cold and dry weather conditions, allowing for enzyme activity inhibition. The second part of the thesis is a simulation study aiming to assess the capacity of the software Structure to detect population structure in hierarchical models relevant to situations encountered in wild populations, using several genetic markers. The methods implemented in Structure appear efficient in detecting the highest hierarchical structure. The third and fourth parts of the thesis describe the population genetics status of the remaining Jura and Pyrenees populations using 11 microsatellite loci. In either of these populations, no inbreeding nor reduced genetic diversity was detected. Furthermore, the genetic differentiation between patches defined by habitat suitability remains moderate and correlated with geographical distance, suggesting that significant dispersion between patches was at work at least until the last generations. The comparison of diversity indicators with other species or other populations of capercaillie indicate that population in the Jura has retained a large part of its original genetic diversity. These results suggest that the recent decline has had so forth a moderate impact on• genetic factors and that these populations might have retained the potential for long term survival, if the decline is stopped. Finally, in the fifth part, the analysis of relatedness between males participating in the reproduction parade, or lek, indicate that capercaillie males, like has been shown for some other grouse species, gather on leks• among individuals that are more related than the average of the population. This pattern appears to be due to both population structure and kin-association. As a conclusion, this first study relying exclusively on nuclear DNA extracted from faeces has provided novel information that was not available through field observation or classical genetic sampling. No bird has been captured or disturbed, and the results are consistent with other studies of closely related species. However, the size of these populations is approaching thresholds below which long-term survival is unlikely. The persistence of genetic diversity for the forthcoming generations remains therefore bond to adult survival and to the increase of reproduction success.

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This thesis presents a topological approach to studying fuzzy setsby means of modifier operators. Modifier operators are mathematical models, e.g., for hedges, and we present briefly different approaches to studying modifier operators. We are interested in compositional modifier operators, modifiers for short, and these modifiers depend on binary relations. We show that if a modifier depends on a reflexive and transitive binary relation on U, then there exists a unique topology on U such that this modifier is the closure operator in that topology. Also, if U is finite then there exists a lattice isomorphism between the class of all reflexive and transitive relations and the class of all topologies on U. We define topological similarity relation "≈" between L-fuzzy sets in an universe U, and show that the class LU/ ≈ is isomorphic with the class of all topologies on U, if U is finite and L is suitable. We consider finite bitopological spaces as approximation spaces, and we show that lower and upper approximations can be computed by means of α-level sets also in the case of equivalence relations. This means that approximations in the sense of Rough Set Theory can be computed by means of α-level sets. Finally, we present and application to data analysis: we study an approach to detecting dependencies of attributes in data base-like systems, called information systems.

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La hiérarchie de Wagner constitue à ce jour la plus fine classification des langages ω-réguliers. Par ailleurs, l'approche algébrique de la théorie de langages formels montre que ces ensembles ω-réguliers correspondent précisément aux langages reconnaissables par des ω-semigroupes finis pointés. Ce travail s'inscrit dans ce contexte en fournissant une description complète de la contrepartie algébrique de la hiérarchie de Wagner, et ce par le biais de la théorie descriptive des jeux de Wadge. Plus précisément, nous montrons d'abord que le degré de Wagner d'un langage ω-régulier est effectivement un invariant syntaxique. Nous définissons ensuite une relation de réduction entre ω-semigroupes pointés par le biais d'un jeu infini de type Wadge. La collection de ces structures algébriques ordonnée par cette relation apparaît alors comme étant isomorphe à la hiérarchie de Wagner, soit un quasi bon ordre décidable de largeur 2 et de hauteur ω. Nous exposons par la suite une procédure de décidabilité de cette hiérarchie algébrique : on décrit une représentation graphique des ω-semigroupes finis pointés, puis un algorithme sur ces structures graphiques qui calcule le degré de Wagner de n'importe quel élément. Ainsi le degré de Wagner de tout langage ω-régulier peut être calculé de manière effective directement sur son image syntaxique. Nous montrons ensuite comment construire directement et inductivement une structure de n''importe quel degré. Nous terminons par une description détaillée des invariants algébriques qui caractérisent tous les degrés de cette hiérarchie. Abstract The Wagner hierarchy is known so far to be the most refined topological classification of ω-rational languages. Also, the algebraic study of formal languages shows that these ω-rational sets correspond precisely to the languages recognizable by finite pointed ω-semigroups. Within this framework, we provide a construction of the algebraic counterpart of the Wagner hierarchy. We adopt a hierarchical game approach, by translating the Wadge theory from the ω-rational language to the ω-semigroup context. More precisely, we first show that the Wagner degree is indeed a syntactic invariant. We then define a reduction relation on finite pointed ω-semigroups by means of a Wadge-like infinite two-player game. The collection of these algebraic structures ordered by this reduction is then proven to be isomorphic to the Wagner hierarchy, namely a well-founded and decidable partial ordering of width 2 and height $\omega^\omega$. We also describe a decidability procedure of this hierarchy: we introduce a graph representation of finite pointed ω-semigroups allowing to compute their precise Wagner degrees. The Wagner degree of every ω-rational language can therefore be computed directly on its syntactic image. We then show how to build a finite pointed ω-semigroup of any given Wagner degree. We finally describe the algebraic invariants characterizing every Wagner degree of this hierarchy.

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The present dissertation is devoted to the systematic approach to the development of organic toxic and refractory pollutants abatement by chemical decomposition methods in aqueous and gaseous phases. The systematic approach outlines the basic scenario of chemical decomposition process applications with a step-by-step approximation to the most effective result with a predictable outcome for the full-scale application, confirmed by successful experience. The strategy includes the following steps: chemistry studies, reaction kinetic studies in interaction with the mass transfer processes under conditions of different control parameters, contact equipment design and studies, mathematical description of the process for its modelling and simulation, processes integration into treatment technology and its optimisation, and the treatment plant design. The main idea of the systematic approach for oxidation process introduction consists of a search for the most effective combination between the chemical reaction and the treatment device, in which the reaction is supposed to take place. Under this strategy,a knowledge of the reaction pathways, its products, stoichiometry and kinetics is fundamental and, unfortunately, often unavailable from the preliminary knowledge. Therefore, research made in chemistry on novel treatment methods, comprisesnowadays a substantial part of the efforts. Chemical decomposition methods in the aqueous phase include oxidation by ozonation, ozone-associated methods (O3/H2O2, O3/UV, O3/TiO2), Fenton reagent (H2O2/Fe2+/3+) and photocatalytic oxidation (PCO). In the gaseous phase, PCO and catalytic hydrolysis over zero valent ironsare developed. The experimental studies within the described methodology involve aqueous phase oxidation of natural organic matter (NOM) of potable water, phenolic and aromatic amino compounds, ethylene glycol and its derivatives as de-icing agents, and oxygenated motor fuel additives ¿ methyl tert-butyl ether (MTBE) ¿ in leachates and polluted groundwater. Gas-phase chemical decomposition includes PCO of volatile organic compounds and dechlorination of chlorinated methane derivatives. The results of the research summarised here are presented in fifteenattachments (publications and papers submitted for publication and under preparation).

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The article proposes an alternative approach to policies for preventing doping in cycling, based on in-depth analysis of the functioning of nine of the 40 world professional teams and the careers of the 2,351 riders who were or have been professionals since 2005. The first part shows that the instruments of prevention have been based on a questionable understanding of doping as an individual moral fault, and have not produced the expected results. The second part proposes to analyse the ways in which teams and riders produce their achievments, so as to put forward an alternative to the anti-doping policies used hitherto, which have little impact on riders. The study shows that it is more pertinent to examine the forms of employment and the business models, because these have important effects on cycling professionals' conditions of work. It makes it possible to identify three dimensions of the risk of doping on which organisations can act in their antidoping policies: team organisation, riders' preparation and workload, and the precarity of employment.