995 resultados para Stochastic Context-Free L-Grammar
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This article describes the long-lasting psychological after-effects of a traumatic experience. There is growing lmowledge of the biomedical underpinnings of these phenomena: the underlying mechanisms belong to an implicit learning process whereby the victim remains under the influence of painful past experiences. One of these mechanisms concerns the development of a traumatic bonding which Iioticeably impedes the establishment of interpersona! relationships. The other mechanism, called "contextualisation deficit", is the difficulty of adjusting a person's emotional and behavioural reactivity to the context of present day !ife. This capacity of a traumatic experience to become incrusted long-termina human being's mind, and to haunt the victim with various forms of psychological and physical suffering, can be compared with the presence of a tumour or an abscess in somatic medicine. Th us, severe drug addiction can be conceptualised as a disorder in which the patient tries - in most cases ineffectively - to soothe the pain of today's world in cmmection with the trauma of the past. In conclusion, this article urges the development of psychiatrie care programmes which operate at the centre of the suffering encountered by the se patients, as a complement to the already well-established offers such as harm reduction, substitution therapy and social support.
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Molecular shape has long been known to be an important property for the process of molecular recognition. Previous studies postulated the existence of a drug-like shape space that could be used to artificially bias the composition of screening libraries, with the aim to increase the chance of success in Hit Identification. In this work, it was analysed to which extend this assumption holds true. Normalized Principal Moments of Inertia Ratios (NPRs) have been used to describe the molecular shape of small molecules. It was investigated, whether active molecules of diverse targets are located in preferred subspaces of the NPR shape space. Results illustrated a significantly stronger clustering than could be expected by chance, with parts of the space unlikely to be occupied by active compounds. Furthermore, a strong enrichment of elongated, rather flat shapes could be observed, while globular compounds were highly underrepresented. This was confirmed for a wide range of small molecule datasets from different origins. Active compounds exhibited a high overlap in their shape distributions across different targets, making a purely shape based discrimination very difficult. An additional perspective was provided by comparing the shapes of protein binding pockets with those of their respective ligands. Although more globular than their ligands, it was observed that binding sites shapes exhibited a similarly skewed distribution in shape space: spherical shapes were highly underrepresented. This was different for unoccupied binding pockets of smaller size. These were on the contrary identified to possess a more globular shape. The relation between shape complementarity and exhibited bioactivity was analysed; a moderate correlation between bioactivity and parameters including pocket coverage, distance in shape space, and others could be identified, which reflects the importance of shape complementarity. However, this also suggests that other aspects are of relevance for molecular recognition. A subsequent analysis assessed if and how shape and volume information retrieved from pocket or respective reference ligands could be used as a pre-filter in a virtual screening approach. ln Lead Optimization compounds need to get optimized with respect to a variety of pararneters. Here, the availability of past success stories is very valuable, as they can guide medicinal chemists during their analogue synthesis plans. However, although of tremendous interest for the public domain, so far only large corporations had the ability to mine historical knowledge in their proprietary databases. With the aim to provide such information, the SwissBioisostere database was developed and released during this thesis. This database contains information on 21,293,355 performed substructural exchanges, corresponding to 5,586,462 unique replacements that have been measured in 35,039 assays against 1,948 molecular targets representing 30 target classes, and on their impact on bioactivity . A user-friendly interface was developed that provides facile access to these data and is accessible at http//www.swissbioisostere.ch. The ChEMBL database was used as primary data source of bioactivity information. Matched molecular pairs have been identified in the extracted and cleaned data. Success-based scores were developed and integrated into the database to allow re-ranking of proposed replacements by their past outcomes. It was analysed to which degree these scores correlate with chemical similarity of the underlying fragments. An unexpectedly weak relationship was detected and further investigated. Use cases of this database were envisioned, and functionalities implemented accordingly: replacement outcomes are aggregatable at the assay level, and it was shawn that an aggregation at the target or target class level could also be performed, but should be accompanied by a careful case-by-case assessment. It was furthermore observed that replacement success depends on the activity of the starting compound A within a matched molecular pair A-B. With increasing potency the probability to lose bioactivity through any substructural exchange was significantly higher than in low affine binders. A potential existence of a publication bias could be refuted. Furthermore, often performed medicinal chemistry strategies for structure-activity-relationship exploration were analysed using the acquired data. Finally, data originating from pharmaceutical companies were compared with those reported in the literature. It could be seen that industrial medicinal chemistry can access replacement information not available in the public domain. In contrast, a large amount of often-performed replacements within companies could also be identified in literature data. Preferences for particular replacements differed between these two sources. The value of combining different endpoints in an evaluation of molecular replacements was investigated. The performed studies highlighted furthermore that there seem to exist no universal substructural replacement that always retains bioactivity irrespective of the biological environment. A generalization of bioisosteric replacements seems therefore not possible. - La forme tridimensionnelle des molécules a depuis longtemps été reconnue comme une propriété importante pour le processus de reconnaissance moléculaire. Des études antérieures ont postulé que les médicaments occupent préférentiellement un sous-ensemble de l'espace des formes des molécules. Ce sous-ensemble pourrait être utilisé pour biaiser la composition de chimiothèques à cribler, dans le but d'augmenter les chances d'identifier des Hits. L'analyse et la validation de cette assertion fait l'objet de cette première partie. Les Ratios de Moments Principaux d'Inertie Normalisés (RPN) ont été utilisés pour décrire la forme tridimensionnelle de petites molécules de type médicament. Il a été étudié si les molécules actives sur des cibles différentes se co-localisaient dans des sous-espaces privilégiés de l'espace des formes. Les résultats montrent des regroupements de molécules incompatibles avec une répartition aléatoire, avec certaines parties de l'espace peu susceptibles d'être occupées par des composés actifs. Par ailleurs, un fort enrichissement en formes allongées et plutôt plates a pu être observé, tandis que les composés globulaires étaient fortement sous-représentés. Cela a été confirmé pour un large ensemble de compilations de molécules d'origines différentes. Les distributions de forme des molécules actives sur des cibles différentes se recoupent largement, rendant une discrimination fondée uniquement sur la forme très difficile. Une perspective supplémentaire a été ajoutée par la comparaison des formes des ligands avec celles de leurs sites de liaison (poches) dans leurs protéines respectives. Bien que plus globulaires que leurs ligands, il a été observé que les formes des poches présentent une distribution dans l'espace des formes avec le même type d'asymétrie que celle observée pour les ligands: les formes sphériques sont fortement sous représentées. Un résultat différent a été obtenu pour les poches de plus petite taille et cristallisées sans ligand: elles possédaient une forme plus globulaire. La relation entre complémentarité de forme et bioactivité a été également analysée; une corrélation modérée entre bioactivité et des paramètres tels que remplissage de poche, distance dans l'espace des formes, ainsi que d'autres, a pu être identifiée. Ceci reflète l'importance de la complémentarité des formes, mais aussi l'implication d'autres facteurs. Une analyse ultérieure a évalué si et comment la forme et le volume d'une poche ou de ses ligands de référence pouvaient être utilisés comme un pré-filtre dans une approche de criblage virtuel. Durant l'optimisation d'un Lead, de nombreux paramètres doivent être optimisés simultanément. Dans ce contexte, la disponibilité d'exemples d'optimisations réussies est précieuse, car ils peuvent orienter les chimistes médicinaux dans leurs plans de synthèse par analogie. Cependant, bien que d'un extrême intérêt pour les chercheurs dans le domaine public, seules les grandes sociétés pharmaceutiques avaient jusqu'à présent la capacité d'exploiter de telles connaissances au sein de leurs bases de données internes. Dans le but de remédier à cette limitation, la base de données SwissBioisostere a été élaborée et publiée dans le domaine public au cours de cette thèse. Cette base de données contient des informations sur 21 293 355 échanges sous-structuraux observés, correspondant à 5 586 462 remplacements uniques mesurés dans 35 039 tests contre 1948 cibles représentant 30 familles, ainsi que sur leur impact sur la bioactivité. Une interface a été développée pour permettre un accès facile à ces données, accessible à http:/ /www.swissbioisostere.ch. La base de données ChEMBL a été utilisée comme source de données de bioactivité. Une version modifiée de l'algorithme de Hussain et Rea a été implémentée pour identifier les Matched Molecular Pairs (MMP) dans les données préparées au préalable. Des scores de succès ont été développés et intégrés dans la base de données pour permettre un reclassement des remplacements proposés selon leurs résultats précédemment observés. La corrélation entre ces scores et la similarité chimique des fragments correspondants a été étudiée. Une corrélation plus faible qu'attendue a été détectée et analysée. Différents cas d'utilisation de cette base de données ont été envisagés, et les fonctionnalités correspondantes implémentées: l'agrégation des résultats de remplacement est effectuée au niveau de chaque test, et il a été montré qu'elle pourrait également être effectuée au niveau de la cible ou de la classe de cible, sous réserve d'une analyse au cas par cas. Il a en outre été constaté que le succès d'un remplacement dépend de l'activité du composé A au sein d'une paire A-B. Il a été montré que la probabilité de perdre la bioactivité à la suite d'un remplacement moléculaire quelconque est plus importante au sein des molécules les plus actives que chez les molécules de plus faible activité. L'existence potentielle d'un biais lié au processus de publication par articles a pu être réfutée. En outre, les stratégies fréquentes de chimie médicinale pour l'exploration des relations structure-activité ont été analysées à l'aide des données acquises. Enfin, les données provenant des compagnies pharmaceutiques ont été comparées à celles reportées dans la littérature. Il a pu être constaté que les chimistes médicinaux dans l'industrie peuvent accéder à des remplacements qui ne sont pas disponibles dans le domaine public. Par contre, un grand nombre de remplacements fréquemment observés dans les données de l'industrie ont également pu être identifiés dans les données de la littérature. Les préférences pour certains remplacements particuliers diffèrent entre ces deux sources. L'intérêt d'évaluer les remplacements moléculaires simultanément selon plusieurs paramètres (bioactivité et stabilité métabolique par ex.) a aussi été étudié. Les études réalisées ont souligné qu'il semble n'exister aucun remplacement sous-structural universel qui conserve toujours la bioactivité quel que soit le contexte biologique. Une généralisation des remplacements bioisostériques ne semble donc pas possible.
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RESUME« L'insertion sociale plurielle des femmes cadres supérieurs en Suisse. Contribution à l'étude du bien-être subjectif au quotidien. Approche intégrative qualitative. »Depuis une quarantaine d'années, nombreux sont les travaux qui étudient les relations entre les différents milieux de vie au quotidien et, plus particulièrement, l'impact de leurs articulations singulières sur la santé. Nous y identifions deux axes principaux : l'un aborde ce phénomène selon une perspective de « conflit travail-famille » en termes de « stress », l'autre se focalise davantage sur la promotion du « bien-être » au travers d'une approche d'« équilibre travail-vie ». Or, l'ensemble de ces recherches considère comme «pathogènes» les désajustements, les contradictions et les tensions vécus au quotidien. Selon cette tendance, le « bien-être » apparaît comme un état d'équilibre ultime indépendant du contexte de vie du sujet. Toutefois, peu de recherches portent sur la dimension située du bien-être dans son rapport à l'activité concrète au sein des milieux deNotre étude s'intéresse à cette question auprès des femmes cadres supérieurs, selon une perspective critique et développementale en psychologie de la santé (Lyons & Chamberlain, 2006 ; Santiago-Delefosse, 2002,2011 ; Malrieu, 1989 ; Vygotski, 1985). En effet, cette population constitue un terrain privilégié pour comprendre le sens donné à l'activité à partir des contraintes, responsabilités et demandes perçues dans des contextes parfois contradictoires, et pour analyser le rôle de ces derniers dans un bien-être subjectif.En cohérence avec notre positionnement théorique, nous avons mené des entretiens qualitatifs focalisés sur l'activité quotidienne auprès de 20 femmes, et ceci en deux temps (T1-T2) (40 entretiens). Les résultats issus des analyses du contenu des discours permettent de définir le vécu de l'articulation des milieux de vie chez nos participantes, selon trois axes à la fois interdépendants et autonomes. Chaque axe se définit par une série de supports spécifiques jouant un rôle structurant dans leur bien-être subjectif. Ainsi, le premier axe se caractérise par des supports de maîtrise subjective, ainsi que par l'appropriation de contraintes sociales et corporelles, selon un rythme de l'activité soutenu. Le deuxième s'accompagne de supports qui favorisent la prise de distance au travers du relâchement du rythme et du lâcher prise de la maîtrise, par la création d'espaces personnels et sociaux « pour soi ». Enfin, le troisième porte sur le positionnement de soi par rapport à autrui en termes de « personnalisation ».Construits en rapport à la corporéité et à autrui au sein de contextes spécifiques, ces différents supports prennent leur sens au sein d'un système de pratiques global, unique pour chaque femme. Selon cette conception critique, le bien-être subjectif chez les femmes cadres se définit comme le fruit d'un processus mouvant issu des tensions vécues entre les trois axes de l'articulation des milieux de vie. Il est par conséquent social, corporel et psychologique.Nos résultats ouvrent des perspectives de recherche et d'intervention, notamment en santé et travail. Ces ouvertures sont orientées vers une approche intégrative en psychologie de la santé, c'est-à-dire, de la prise en compte dans des questions de santé et de bien-être du processus de construction du sujet en relation à son insertion sociale plurielle.ABSTRACT« Plural social participation among women senior managers in Switzerland. Contribution to the study of subjective well-being in everyday life. An integrative and qualitativeapproach.»For the last forty years, a large body of literature has studied the relationships between different social realms in everyday life and, more particularly, the impact of their singular intertwinements with health. We identify two main trends : The first one focuses on this phenomenon through the « work-family conflict » perspective in terms of « stress » whilst the second one is more concerned by the promotion of « well-being » through a « work-life balance » approach. However, both of these trends consider disadjustments, contradictions and tensions in everyday life as « pathogenic ». According to this conception, « well- being » appears as an ultimate state of balance which is indépendant from the subject's life context. Nevertheless, few studies have examined the situated dimension of well-being in its link to concrete activity in social realms.Our research is concerned with this issue among women senior managers from a critical and developmental perspective in Health Psychology (Lyons & Chamberlain, 2006 ; Santiago-Delefosse, 2002, 2011 ; Malrieu, 1989 ; Vygotski, 1985). In fact, this population represents a favourable field so as to study : how the meaning of daily activity is constructed accross different and often conflictive social realms ; to understand the many ways in which this population deals with perceived constraints, responsibilities and requests, and to analyse the role of situated plural activity in subjective well-being.Consitent with our theoretical framework, we have designed a qualitative method. We have conducted two-time (T1-T2) interviews with 20 women by focusing on their daily activity (40 interviews). The Thematic Content Analysis reveals that four different social realms are articulated among our participants through three main axes, which are at the same time interdependent and autonomous. Each one of these axis is defined by a certain number of specific supports that play an important role in these women's subjective well- being. The first axis is concerned by several supports that signify a « feeling of control » along with the appropriation of social and body constraints by means of a rapid pace of activity. The second one regards the use of supports that contribute to « put things into perspective » by means of the slowing down of the pace of activity and through letting go of the feeling of control. This mechanism includes the creation of personal and social spaces of « one's own ». The third axis is defined by the positioning of the self in regard to others through a process of « personnalization ».Developed in specific contexts through the intertwinnements between the body and social others, supports belonging to these axes acquire significance and meaning on the basis of their relationship to a global system of activities of which they are part. However, this articulation is uniquely defined for each participant. According to this critical approach, subjective well-being among women senior managers emerges as a meaningful and changing process, situated in a plural social context. This is, it appears as the result of conflictual interactions defining the three different axis that we have identified. Subjective well-being is hence a social, embodied and psychological phenomena that is closely linked to the articulation of different social realms. Our findings open new research and practice perspectives, especially concerning health and work issues. These perspectives convey an integrative approach in Health Psychology by considering health and well-being by taking into account the process of construction of the subject in regard to his or her plural social participation.
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Abstract Animal behaviours or structures are used by senders as signals to try to increase their fitness by altering the behaviour of receivers. A large fraction of studies on sexual selection have focussed on male ornaments and have demonstrated that these ornaments signal the quality of their owner and are used by female for mate choice. Although females can also exhibit conspicuous traits, studies on female ornaments are markedly lacking. In chapter 1, we show that female starlings are showier on chest whiteness than males and that females' whiteness may potentially indicate female condition at the start of breeding and provide fitness advantages to breeding birds. Furthermore we point out that feather density and abrasion are important factors shaping the expression of chest whiteness. This suggests that further understanding of the evolution of chest whiteness in Starlings requires to examine the environmental and physiological factors that shape feather condition. Plumage may suffer from damage through abrasion and bacterial activity. In chapter 2, we focus on factors that influence feather-degrading bacterial communities. Within the hypothesis that parental care can be trade-off against the demands of self-maintenance, we show that a brood size manipulation modifies the structure of feather-degrading bacterial communities and the density of free- living bacteria. Thus we have pointed out a potentially poorly known cost of reproduction. In the same context of a trade-off between reproductive activities and individual self-maintenance, chapter 3 shows that at a proximate level in females but not in males, the individual variation in time and/or energy allocated in reproductive activities is associated with prolactin hormone levels. Our study provides evidence for the existence of a sex related difference in the relationship between brood size and prolactin levels. Birds have evolved sanitation behaviours and preen gland secretions to preserve the condition of their plumage. In chapter 4, we describe a method that allows to measure preen gland in situ. Then we use this method to characterize a number of phenotypic and ecological factors that explain variation in preen gland size in free-living individuals. In parent-offspring interactions, parents use offspring signals to provision their brood. In chapter 5, we demonstrate that nestling flanges and body skin reflect in the ultra-violet (UV) wavelengths ant that parents use this UV reflectance in food allocation decisions. Résumé Certains comportements et structures chez les animaux agissent, pour ceux qui les émettent, comme des signaux permettant d'augmenter leur fitness en altérant les comportements de ceux qui les perçoivent. Une grande partie des études sur la sélection sexuelle s'est focalisée sur les ornements mâles. Ces études ont démontré que ces ornements pouvaient signaler la qualité de celui qui les porte et influencer le choix des femelles. Bien que les femelles puissent aussi présenter des traits voyants, les études sur leurs ornements font défaut. Dans le chapitre 1 de ce travail, nous montrons que les étourneaux femelles sont plus voyantes que les mâles sur la base de la blancheur de la poitrine. De plus la blancheur des femelles peut signaler leur condition au début de la saison de reproduction et ainsi être corrélée avec leur fitness. Nous mettons aussi en évidence que la densité et l'abrasion des plumes sont des facteurs importants, contrôlant l'expression de la blancheur de la poitrine. Ceci suggère que des études futures pourraient examiner le rôle des facteurs environnementaux et physiologiques qui influencent la condition des plumes pour mieux comprendre l'évolution de la blancheur chez les étourneaux. Le plumage subit des dommages à travers l'abrasion et probablement aussi par l'activité de dégradation de bactéries. Dans le chapitre 2 de ce travail, nous nous intéressons aux facteurs qui influencent les communautés de bactéries dégradant les plumes. Nous basant sur l'hypothèse selon laquelle il existe un compromis entre les soins parentaux et la maintenance corporelle, nous montrons qu'une manipulation de la taille de nichée modifie la structure des communautés de bactéries dégradant les plumes ainsi que les densités de bactéries libres présentes sur le plumage. Ainsi nous mettons en évidence un coût encore peu connu des activités de reproduction. Dans le même contexte, nous montrons, dans le chapitre 3, que des variations individuelles dans l'énergie et/ou le temps alloué dans les activités de reproduction sont associés, chez les femelles, à un niveau proximal à l'hormone prolactine. Cette relation n'est pas présente chez les mâles. Cette étude montre que la relation entre la taille de nichée et les niveaux de prolactine diffère avec le sexe des individus. Les oiseaux utilisent des comportements de nettoyage associés aux sécrétions de la glande uropygiale afin de préserver la condition de leurs plumes. Dans le chapitre 4 de ce travail, nous décrivons une méthode qui permet de mesurer la taille de la glande in situ. Puis nous caractérisons certains facteurs écologiques et physiologiques qui expliquent les variations de la taille de la glande chez des individus capturés dans leur environnement. Les parents nourrissent leur progéniture en réponse à des signaux émis par ceux-ci. Dans le chapitre 5 de ce travail, nous démontrons que les commissures et la peau sur le corps des oisillons reflètent la lumière dans l'ultraviolet. Nous montrons que les parents utilisent cette réflexion dans l'ultraviolet lors de l'allocation de nourriture pour leurs jeunes.
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Executive Summary The unifying theme of this thesis is the pursuit of a satisfactory ways to quantify the riskureward trade-off in financial economics. First in the context of a general asset pricing model, then across models and finally across country borders. The guiding principle in that pursuit was to seek innovative solutions by combining ideas from different fields in economics and broad scientific research. For example, in the first part of this thesis we sought a fruitful application of strong existence results in utility theory to topics in asset pricing. In the second part we implement an idea from the field of fuzzy set theory to the optimal portfolio selection problem, while the third part of this thesis is to the best of our knowledge, the first empirical application of some general results in asset pricing in incomplete markets to the important topic of measurement of financial integration. While the first two parts of this thesis effectively combine well-known ways to quantify the risk-reward trade-offs the third one can be viewed as an empirical verification of the usefulness of the so-called "good deal bounds" theory in designing risk-sensitive pricing bounds. Chapter 1 develops a discrete-time asset pricing model, based on a novel ordinally equivalent representation of recursive utility. To the best of our knowledge, we are the first to use a member of a novel class of recursive utility generators to construct a representative agent model to address some long-lasting issues in asset pricing. Applying strong representation results allows us to show that the model features countercyclical risk premia, for both consumption and financial risk, together with low and procyclical risk free rate. As the recursive utility used nests as a special case the well-known time-state separable utility, all results nest the corresponding ones from the standard model and thus shed light on its well-known shortcomings. The empirical investigation to support these theoretical results, however, showed that as long as one resorts to econometric methods based on approximating conditional moments with unconditional ones, it is not possible to distinguish the model we propose from the standard one. Chapter 2 is a join work with Sergei Sontchik. There we provide theoretical and empirical motivation for aggregation of performance measures. The main idea is that as it makes sense to apply several performance measures ex-post, it also makes sense to base optimal portfolio selection on ex-ante maximization of as many possible performance measures as desired. We thus offer a concrete algorithm for optimal portfolio selection via ex-ante optimization over different horizons of several risk-return trade-offs simultaneously. An empirical application of that algorithm, using seven popular performance measures, suggests that realized returns feature better distributional characteristics relative to those of realized returns from portfolio strategies optimal with respect to single performance measures. When comparing the distributions of realized returns we used two partial risk-reward orderings first and second order stochastic dominance. We first used the Kolmogorov Smirnov test to determine if the two distributions are indeed different, which combined with a visual inspection allowed us to demonstrate that the way we propose to aggregate performance measures leads to portfolio realized returns that first order stochastically dominate the ones that result from optimization only with respect to, for example, Treynor ratio and Jensen's alpha. We checked for second order stochastic dominance via point wise comparison of the so-called absolute Lorenz curve, or the sequence of expected shortfalls for a range of quantiles. As soon as the plot of the absolute Lorenz curve for the aggregated performance measures was above the one corresponding to each individual measure, we were tempted to conclude that the algorithm we propose leads to portfolio returns distribution that second order stochastically dominates virtually all performance measures considered. Chapter 3 proposes a measure of financial integration, based on recent advances in asset pricing in incomplete markets. Given a base market (a set of traded assets) and an index of another market, we propose to measure financial integration through time by the size of the spread between the pricing bounds of the market index, relative to the base market. The bigger the spread around country index A, viewed from market B, the less integrated markets A and B are. We investigate the presence of structural breaks in the size of the spread for EMU member country indices before and after the introduction of the Euro. We find evidence that both the level and the volatility of our financial integration measure increased after the introduction of the Euro. That counterintuitive result suggests the presence of an inherent weakness in the attempt to measure financial integration independently of economic fundamentals. Nevertheless, the results about the bounds on the risk free rate appear plausible from the view point of existing economic theory about the impact of integration on interest rates.
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Background: The anti-angiogenic drug, bevacizumab (Bv), is currently used in the treatment of different malignancies including breast cancer. Many angiogenesis-associated molecules are found in the circulation of cancer patients. Until now, there are no prognostic or predictive factors identified in breast cancer patients treated with Bv. We present here the first results of the prospective monitoring of 6 angiogenesis-related molecules in the peripheral blood of breast cancer patients treated with a combination of Bv and PLD in the phase II trial, SAKK 24/06. Methods: Patients were treated with PLD (20 mg/m2) and Bv (10 mg/kg) on days 1 and 15 of each 4-week cycle for a maximum of 6 cycles, followed by Bv monotherapy maintenance (10 mg/m2 q2 weeks) until progression or severe toxicity. Plasma and serum samples were collected at baseline, after 2 months of therapy, then every 3 months and at treatment discontinuation. Enzyme-linked immunosorbent assays (Quantikine, R&D Systems and Reliatech) were used to measure the expression levels of human vascular endothelial growth factor (hVEGF), placental growth factor (hPlGF), matrix metalloproteinase 9 (hMMP9) and soluble VEGF receptors hsVEGFR-1, hsVEGFR-2 and hsVEGFR-3. The log-transformed data (to reduce the skewness) for each marker was analyzed using an analysis of variance (ANOVA) model to determine if there was a difference between the mean of the subgroups of interest (where α = 0.05). The untransformed data was also analyzed in the same manner as a "sensitivity" check. Results: 132 blood samples were collected in 41 out of 43 enrolled patients. Baseline levels of the molecules were compared to disease status according to RECIST. There was a statistically significant difference in the mean of the log-transformed levels of hMMP9 between responders [CR+PR] versus the mean in patients with PD (p-value=0.0004, log fold change=0.7536), and between patients with disease control [CR+PR+SD] and those with PD (p-value=<0.0001, log fold change=0.81559), with the log-transformed level of hMMP9 being higher for the responder group. The mean of the log-transformed levels of hsVEGFR-1 was statistically significantly different between patients with disease control [CR+PR+SD] and those with PD (p-value=0.0068, log fold change=-0.6089), where the log-transformed level of hsVEGFR-1 was lower for the responder group. The log-transformed level of hMMP9 at baseline was identified as a significant prognostic factor in terms of progression free survival (PFS): p-value=0.0417, hazard ratio (HR)=0.574 with a corresponding 95% confidence interval (0.336 - 0.979)). No strong correlation was shown either between the log-transformed levels of hsVEGF, hPlGF, hsVEGFR-2 or hsVEGFR-3 and clinical response or the occurrence of severe toxicity, or between the levels of the different molecules. Conclusions: Our results suggest that baseline plasma level of the matrix metalloproteinase, hMMP9, could predict tumor response and PFS in patients treated with a combination of Bv and PLD. These data justify further investigation in breast cancer patients treated with anti-angiogenic therapy.
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During episodes of trauma carnitine-free total parenteral nutrition (TPN) may result in a reduction of the total body carnitine pool, leading to a diminished rate of fat oxidation. Sixteen patients undergoing esophagectomy were equally and randomly divided and received isonitrogenous (0.2 gN/kg.day) and isocaloric (35 kcal/kg.day TPN over 11 days without and with L-carnitine supplementation (12 mg/kg.day). Compared with healthy controls, the total body carnitine pool was significantly reduced in both groups prior to the operation. Without supplementation carnitine concentrations were maintained, while daily provision of carnitine resulted in an elevation of total carnitine mainly due to an increase of the free fraction. Without supplementation the cumulative urinary carnitine losses were 11.5 +/- 6.3 mmol corresponding to 15.5% +/- 8.5% of the estimated total body carnitine pool. Patients receiving carnitine revealed a positive carnitine balance in the immediate postoperative phase, 11.1% +/- 19.0% of the infused carnitine being retained. After 11 days of treatment comparable values for respiratory quotient, plasma triglycerides, free fatty acids, ketone bodies, and cumulative nitrogen balance were observed. It is concluded that in the patient population studied here carnitine supplementation during postoperative TPN did not improve fat oxidation or nitrogen balance.
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In the context of demographic evolution, psychiatric care needs increase steadily in most western countries. Given the financial limitations, it is mandatory to establish appropriate care priorities in order to avoid psychiatric hospitalisations by assisting care providers, general practionners and nurses, at home or in the nursing homes. A crisis team has been established 18 months ago within the Division of old age psychiatry in Lausanne. The care program included immediate assistance in the community, assessement, crisis counseling, medication consultation and referral for psychiatric services providing an alternative to hospitalization. The first results indicate that this intervention is well accepted by the users and correspond to a real need.
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In inflationary cosmological models driven by an inflaton field the origin of the primordial inhomogeneities which are responsible for large-scale structure formation are the quantum fluctuations of the inflaton field. These are usually calculated using the standard theory of cosmological perturbations, where both the gravitational and the inflaton fields are linearly perturbed and quantized. The correlation functions for the primordial metric fluctuations and their power spectrum are then computed. Here we introduce an alternative procedure for calculating the metric correlations based on the Einstein-Langevin equation which emerges in the framework of stochastic semiclassical gravity. We show that the correlation functions for the metric perturbations that follow from the Einstein-Langevin formalism coincide with those obtained with the usual quantization procedures when the scalar field perturbations are linearized. This method is explicitly applied to a simple model of chaotic inflation consisting of a Robertson-Walker background, which undergoes a quasi-de Sitter expansion, minimally coupled to a free massive quantum scalar field. The technique based on the Einstein-Langevin equation can, however, deal naturally with the perturbations of the scalar field even beyond the linear approximation, as is actually required in inflationary models which are not driven by an inflaton field, such as Starobinsky¿s trace-anomaly driven inflation or when calculating corrections due to nonlinear quantum effects in the usual inflaton driven models.
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We show that the solution published in the paper by Senovilla [Phys. Rev. Lett. 64, 2219 (1990)] is geodesically complete and singularity-free. We also prove that the solution satisfies the stronger energy and causality conditions, such as global hyperbolicity, the strong energy condition, causal symmetry, and causal stability. A detailed discussion about which assumptions in the singularity theorems are not satisfied is performed, and we show explicitly that the solution is in accordance with those theorems. A brief discussion of the results is given.
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Seeing and analyzing crowd control : considerations on the study of festive gatherings through the use of audiovisual material. The goal of our research project was to analyze the mechanisms of crowd control on the occasion of the 2008 European Football Championship held in Geneva. In this article, we describe the necessary ambiguity of these occasions for public authorities. On the one hand, they must guarantee that the occasion is sufficiently secure to avoid infractions or incivilities by fans ; on the other hand, they must create the conditions for a festive event of which exuberance is a central part. Police forces aim not to eliminate excesses but to contain them, since some degree of excess is indispensable to ensure the accomplishment of the event. How does the police deal with this complicated situation ? Where is the limit between preventive and repressive measures ? How do they implement management of the public order in the setting of a sports event ? We aim to render visible the practical conditions of the event by making use of video sequences recorded during a match in Geneva. The empirical materials collected will be used to describe three different situations that highlight how quickly fan action can radically switch natures and how complex it is for the police to face a jubilant crowd. In such a context, we show that assuring the smooth progress of the event requires a redefinition of the role of the police, whose interventions must tread a fine line between permissiveness and prohibition.
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Résumé L'objectif de la thèse est de comprendre le mode d'organisation économique spécifique aux petits centres urbains qui composent les espaces frontaliers sahéliens, en s'interrogeant sur leur concurrence ou leur complémentarité éventuelle à l'intérieur d'un régime de spatialité particulier. En s'appuyant sur l'exemple du carrefour économique de Gaya-Malanville-Kamba situé à la frontière entre le Niger, le Bénin et le Nigeria, il questionne le rôle de la ville-frontière ainsi que le jeu des acteurs marchands localement dominants, à partir de quatre grandes interrogations : Quelles sont les spécificités de l'Afrique sahélienne qui obligent à renouveler les approches géographiques de l'espace marchand? Quels sont les facteurs déterminants de l'activité économique frontalière? Les formes d'organisation de l'espace qui concourent à la structuration de l'économie sont-elles concurrentes ou coopératives? Les logiques économiques frontalières sont-elles compatibles avec l'orientation des programmes de développement adoptés par les pays sahéliens et leurs partenaires bi- ou multilatéraux? Dans une première partie, un modèle territorial de l'Afrique sahélienne permet de rendre compte de la prédominance des logiques circulatoires sur les logiques productives, une propriété essentielle de toute organisation économique confrontée à l'instabilité climatique. Dans une seconde partie, l'étude considère les facteurs déterminants de l'activité économique frontalière que sont le degré d'enclavement des territoires, la libre circulation des biens et des personnes, les relations concurrentielles ou coopératives qui lient les marchés ainsi que les liens clientélistes qui unissent patron et obligés. Une troisième partie est consacrée aux productions agricoles de tente organisées sous forme de coopératives paysannes ou d'initiatives privées. Une quatrième partie s'intéresse aux réseaux de l'import-export et du commerce de détail qui bénéficient de l'augmentation des besoins engendrée par l'urbanisation sahélienne. L'économie spatiale qui résulte de ces flux est organisée selon deux logiques distinctes : d'une part, les opportunités relatives à la production agricole conduisent certains investisseurs à intensifier l'irrigation pour satisfaire la demande des marchés urbains, d'autre part, les acteurs du capitalisme marchand, actifs dans l'import-export et la vente de détail, développent des réseaux informels et mobiles qui se jouent des différentiels nationaux. Les activités commerciales des villes-marchés connaissent alors des fluctuations liées aux entreprises productives et circulatoires de ces patrons, lesquelles concourent à l'organisation territoriale générale de l>Afrique sahélienne. Ces logiques évoluent dans un contexte fortement marqué par les politiques des institutions financières internationales, des agences bilatérales de coopération et des ONGs. Celles-ci se donnent pour ambition de transformer les économies, les systèmes politiques et les organisations sociales sahéliennes, en faisant la promotion du libéralisme, de la bonne gouvernance et de la société civile. Ces axes directeurs, qui constituent le champ de bataille contemporain du développement, forment un ensemble dans lequel la spécificité sahélienne notamment frontalière est rarement prise en compte. C'est pourquoi l'étude conclut en faveur d'un renouvellement des politiques de développement appliquées aux espaces frontaliers. Trois grands axes d'intervention peuvent alors être dégagés, lesquels permettent de réconcilier des acteurs et des logiques longtemps dissociés: ceux des espaces séparés par une limite administrative, ceux de la sphère urbaine et rurale et ceux du capitalisme marchand et de l'investissement agricole, en renforçant la coopération économique transfrontalière, en prenant en considération les interactions croissantes entre villes et campagnes et en appuyant les activités marchandes. Abstract: Urbanisation in West Africa is recent and fast. If only 10 % of the total population was living in urban areas in 1950, this proportion reached 40 % in 2000 and will be estimated to 60 % in 2025. Small and intermediate cities, located between the countryside and large metropolis, are particularly concerned with this process. They are nowadays considered as efficient vectors of local economic development because of fiscal or monetary disparities between states, which enable businessmen to develop particular skills based on local urban networks. The majority of theses networks are informal and extremely flexible, like in the Gaya - Malanville - Kamba region, located between Niger, Benin and Nigeria. Evidence show that this economic space is characterised by high potentialities (climatic and hydrological conditions, location on main economic West African axis) and few constraints (remoteness of some potentially high productive areas). In this context, this PhD deals with the economic relationships between the three market cities. Focusing on the links that unite the businessmen of the local markets - called patron; - it reveals the extreme flexibility of their strategies as well as the deeply informal nature of their activities. Through the analysis of examples taken from the commerce of agricultural products, import and export flows and detail activities, it studies the changes that have taken place in the city centres of Gaya, Malanville and Kamba. Meanwhile, this research shows how these cities represent a border economical area based on rival and complementary connections. In the first Part, it was necessary to reconsider the usual spatial analysis devoted to the question of economic centrality. As a matter of fact, the organisation of West African economic spaces is very flexible and mobile. Centrality is always precarious because of seasonal or temporary reasons. This is why the first chapters are devoted to the study of the specificity of the Sahelian territoriality. Two main elements are relevant: first the population diversity and second, the urban-rural linkages. In the second part, the study considers three main factors on which the cross-border economic networks are dependent: enclosure that prevents goods to reach the markets, administrative constraints that limit free trade between states and cities and the concurrent or complementary relationships between markets. A third part deals with the clientelist ties engaged between the patrons and their clients with the hypothesis that these relationships are based on reciprocity and inequality. A fourth part is devoted to' the study of the spatial organisation of commercial goods across the borders, as far as the agriculture commercial products, the import-export merchandises and the retail products are concerned. This leads to the conclusion that the economic activity is directly linked to urban growth. However, the study notices that there is a lack of efficient policies dealing with strengthening the business sector and improving the cross-border cooperation. This particularity allows us to favour new local development approaches, which would take into account the important potential of private economical actors. In the same time, the commercial flows should be regulated with the help of public policies, as long as they are specifically adapted to the problems that these areas have to deal with.
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We obtain the exact analytical expression, up to a quadrature, for the mean exit time, T(x,v), of a free inertial process driven by Gaussian white noise from a region (0,L) in space. We obtain a completely explicit expression for T(x,0) and discuss the dependence of T(x,v) as a function of the size L of the region. We develop a new method that may be used to solve other exit time problems.