U.S.-Norway Comparison of Interval Breast Cancers

Background: Publications from the International Breast Screening Network (IBSN) have shown that varying definitions create hurdles for comparison of screening performance. Interval breast cancer rates are particularly affected. Objective: to test whether variations in definition of interval cancer rates (ICR) affect comparisons of international ICR, specific to a comparison of ICR in Norway and North Carolina (NC). Methods: An interval cancer (IC) was defined as a cancer diagnosed following a negative screening mammogram in a defined follow-up period. ICR was calculated for women ages 50-69, at subsequent screening in Norway and NC, during the time period 1996 - 2002. ICR was defined using three different denominators (negative screens, negative final assessments and all screens) and three different numerators (DCIS, invasive cancer and all cancers). ICR was then calculated with two methods: 1) number of ICs divided by the number of screens, and ICs divided by the number of women-years at risk for IC. Results: There were no differences in ICR depending on the definition used. In the 1-12 month follow up period ICR (based on number of screens) were: 0.53, 0.54, and 0.54 for Norway; and 1.20, 1.25 and 1.17 for NC, for negative screens, negative final assessment and all screens, respectively: The same trend was seen for 13-24 and 1-24 months follow-up. Using women-years for the analysis did not change the trend. ICR was higher in NC compared to Norway under all definitions and in all follow-up time periods, regardless of calculation method. Conclusion: The ICR within or between Norway and NC did not differ by definition used. ICR were higher in NC than Norway. There are many potential explanations for the difference.

Consommation de cannabis : quels sont les risques ?

Abstract - Cannabis: what are the risks ? Cannabinoids from cannabis have a dual use and display often opposite pharmacological properties depending on the circumstances of use and the administered dose. Cannabinoids constitute mainly a recreative or addictive substance, but also a therapeutic drug. They can be either neurotoxic or neuroprotector, carcinogenic or an anti-cancer drug, hyperemetic or antiemetic, pro-inflammatory or anti-inflammatory... Improvement in in-door cultivation techniques and selection of high yield strains have resulted in a steadily increase of THC content. Cannabis is the most frequently prohibited drug used in Switzerland and Western countries. About half of teenagers have already experimented cannabis consumption. About 10% of cannabis users smoke it daily and can be considered as cannabis-dependant. About one third of these cannabis smokers are chronically intoxicated. THC, the main psychoactive drug interacts with the endocannnabinoid system which is made of cellular receptors, endogenous ligands and a complex intra-cellular biosynthetic, degradation and intra-cellular messengers machinery. The endocannabinoid system plays a major role in the fine tuning of the nervous system. It is thought to be important in memory, motor learning, and synaptic plasticity. At psychoactive dose, THC impairs psychomotor and neurocognitive performances. Learning and memory abilities are diminished. The risk to be responsible of a traffic car accident is slightly increased after administration of cannabis alone and strongly increased after combined use of alcohol and cannabis. With the exception of young children, cannabis intake does not lead to potentially fatal intoxication. However, cannabis exposure can act as trigger for cardiovascular accidents in rare vulnerable people. Young or vulnerable people are more at risk to develop a psychosis at adulthood and/or to become cannabis-dependant. Epidemiological studies have shown that the risk to develop a schizophrenia at adulthood is increased for cannabis smokers, especially for those who are early consumers. Likewise for the risk of depression and suicide attempt. Respiratory disease can be worsen after cannabis smoking. Pregnant and breast-feeding mothers should not take cannabis because THC gets into placenta and concentrates in breast milk. The most sensitive time-period to adverse side-effects of cannabis starts from foetus and extends to adolescence. The reason could be that the endocannabinoid system, the main target of THC, plays a major role in the setup of neuronal networks in the immature brain. The concomitant use of other psychoactive drugs such as alcohol, benzodiazepines or cocaine should be avoided because of possible mutual interactions. Furthermore, it has been demonstrated that a cross-sensitisation exists between most addictive drugs at the level of the brain reward system. Chronic use of cannabis leads to tolerance and withdrawals symptoms in case of cannabis intake interruption. Apart from the aforementioned unwanted side effects, cannabis displays useful and original medicinal properties which are currently under scientific evaluation. At the moment the benefit/risk ratio is not yet well assessed. Several minor phytocannabinoids or synthetic cannabinoids devoid of psychoactive properties could find their way in the modern pharmacopoeia (e.g. ajulemic acid). For therapeutic purposes, special cannabis varieties with unique cannabinoids composition (e.g. a high cannabidiol content) are preferred over those which are currently used for recreative smoking. The administration mode also differs in such a way that inhalation of carcinogenic pyrolytic compounds resulting from cannabis smoking is avoided. This can be achieved by inhaling cannabis vapors at low temperature with a vaporizer device. Résumé Les cannabinoïdes contenus dans la plante de cannabis ont un double usage et possèdent des propriétés opposées suivant les circonstances et les doses employées. Les cannabinoïdes, essentiellement drogue récréative ou d'abus pourraient, pour certains d'entre eux, devenir des médicaments. Selon les conditions d'utilisation, ils peuvent être neurotoxiques ou neuroprotecteurs, carcinogènes ou anticancéreux, hyper-émétiques ou antiémétiques, pro-inflammatoires ou anti-inflammatoires... Les techniques de culture sous serre indoor ainsi que la sélection de variétés de cannabis à fort potentiel de production ont conduit à un accroissement notable des taux de THC. Le cannabis est la drogue illégale la plus fréquemment consommée en Suisse et ailleurs dans le monde occidental. Environ la moitié des jeunes ont déjà expérimenté le cannabis. Environ 10 % des consommateurs le fument quotidiennement et en sont devenus dépendants. Un tiers de ces usagers peut être considéré comme chroniquement intoxiqué. Le THC, la principale substance psychoactive du cannabis, interagit avec le "système endocannabinoïde". Ce système est composé de récepteurs cellulaires, de ligands endogènes et d'un dispositif complexe de synthèse, de dégradation, de régulation et de messagers intra-cellulaires. Le système endocannabinoïde joue un rôle clé dans le réglage fin du système nerveux. Les endocannabinoïdes régulent la mémorisation, l'apprentissage moteur et la plasticité des liaisons nerveuses. À dose psychoactive, le THC réduit les performances psychomotrices et neurocognitives. Les facultés d'apprentissage et de mémorisation sont diminuées. Le risque d'être responsable d'un accident de circulation est augmenté après prise de cannabis, et ceci d'autant plus que de l'alcool aura été consommé parallèlement. À l'exception des jeunes enfants, la consommation de cannabis n'entraîne pas de risque potentiel d'intoxication mortelle. Toutefois, le cannabis pourrait agir comme facteur déclenchant d'accident cardiovasculaire chez de rares individus prédisposés. Les individus jeunes, et/ou vulnérables ont un risque significativement plus élevé de développer une psychose à l'âge adulte ou de devenir dépendant au cannabis. Des études épidémiologiques ont montré que le risque de développer une schizophrénie à l'âge adulte était augmenté pour les consommateurs de cannabis et ceci d'autant plus que l'âge de début de consommation était précoce. Il en va de même pour le risque de dépression. Les troubles respiratoires pourraient être exacerbés par la prise de cannabis. Les femmes enceintes et celles qui allaitent ne devraient pas consommer de cannabis car le THC traverse la barrière hémato-placentaire, en outre, il se concentre dans le lait maternel. La période de la vie la plus sensible aux effets néfastes du cannabis correspond à celle allant du foetus à l'adolescent. Le système endocannabinoïde sur lequel agit le THC serait en effet un acteur majeur orchestrant le développement des réseaux neuronaux dans le cerveau immature. La prise concomitante d'autres psychotropes comme l'alcool, les benzodiazépines ou la cocaïne conduit à des renforcements mutuels de leurs effets délétères. De plus, il a été montré l'existence d'une sensibilité croisée pour la majorité des psychotropes qui agissent sur le système de la récompense, le cannabis y compris, ce qui augmente ainsi le risque de pharmacodépendance. La prise régulière de doses élevées de cannabis entraîne l'apparition d'une tolérance et de symptômes de sevrage discrets à l'arrêt de la consommation. À part les effets négatifs mentionnés auparavant, le cannabis possède des propriétés médicales originales qui sont l'objet d'études attentives. Plusieurs cannabinoïdes mineurs naturels ou synthétiques, comme l'acide ajulémique, pourraient trouver un jour une place dans la pharmacopée. En usage thérapeutique, des variétés particulières de cannabis sont préférées, par exemple celles riches en cannabidiol non psychoactif. Le mode d'administration diffère de celui utilisé en mode récréatif. Par exemple, la vaporisation des cannabinoïdes à basse température est préférée à l'inhalation du "joint".

Stable isotopes in lake Geneva carbonate sediments and molluscs: Review and new data

New isotopic results on bulk carbonate and mollusc (gastropods and bivalves) samples from Lake Geneva (Switzerland), spanning the period from the Oldest Dryas to the present day, are compared with pre-existing stable isotope data. According to preliminary calibration of modern samples, Lake Geneva endogenic calcite precipitates at or near oxygen isotopic equilibrium with ambient water, confirming the potential of this large lake to record paleoenvironmental and paleoclimatic changes. The onset of endogenic calcite precipitation at the beginning of the Allerod biozone is clearly indicated by the oxygen isotopic signature of bulk carbonate. A large change in delta(13)C values occurs during the Preboreal. This carbon shift is likely to be due to a change in bioproductivity and/or to a `'catchment effect'', the contribution of biogenic CO2 from the catchment area to the dissolved inorganic carbon reservoir of the lake water becoming significant only during the Preboreal. Gastropods are confirmed as valuable for studies of changes in paleotemperature and in paleowater isotopic composition, despite the presence of a vital effect. Mineralogical evidence indicates an increased detrital influence upon sedimentation since the Subboreal time period. On the other hand, stable isotope measurements of Subatlantic carbonate sediments show values comparable to those of pure endogenic calcite and of gastropods (taking into account the vital effect). This apparent disagreement still remains difficult to explain.

Basic life support teaching in the second year predraduate medical curriculum: quality of acquisition after 6 months

Purpose of the study: Basic life support (BLS) and automated externaldefibrillation (AED) represent important skills to be acquired duringpregraduate medical training. Since 3 years, our medical school hasintroduced a BLS-AED course (with certification) for all second yearmedical students. Few reports about quality and persistence over timeof BLS-AED learning are available to date in the medical literature.Comprehensive evaluation of students' acquired skills was performedat the end of the 2008 academic year, 6 month after certification.Materials and methods: The students (N = 142) were evaluated duringa 9 minutes «objective structured clinical examination» (OSCE) station.Out of a standardized scenario, they had to recognize a cardiac arrestsituation and start a resuscitation process. Their performance wererecorded on a PC using an Ambuman(TM) mannequin and the AmbuCPR software kit(TM) during a minimum of 8 cycles (30 compressions:2 ventilations each). BLS parameters were systematically checked. Nostudent-rater interactions were allowed during the whole evaluation.Results: Response of the victim was checked by 99% of the students(N = 140), 96% (N = 136) called for an ambulance and/or an AED. Openthe airway and check breathing were done by 96% (N = 137), 92% (N =132) gave 2 rescue breaths. Pulse was checked by 95% (N=135), 100%(N = 142) begun chest compression, 96% (N = 136) within 1 minute.Chest compression rate was 101 ± 18 per minute (mean ± SD), depthcompression 43 ± 8 mm, 97% (N = 138) respected a compressionventilationratio of 30:2.Conclusions: Quality of BLS skills acquisition is maintained during a6-month period after a BLS-AED certification. Main targets of 2005 AHAguidelines were well respected. This analysis represents one of thelargest evaluations of specific BLS teaching efficiency reported. Furtherfollow-up is needed to control the persistence of these skills during alonger time period and noteworthy at the end of the pregraduatemedical curriculum.

Persistence of Increased Eotaxin-1 (CCL11) Level in Tears of Patients Wearing Contact Lenses: A Long-Term Follow-Up Study.

BACKGROUND: Eotaxin-1 (CCL11) is a potent eosinophil chemotactic and activating peptide that may be implicated in the pathogenesis of chronic allergic eye disease and has been associated with the wearing of contact lenses (CL) in patients with contact lens papillary conjunctivitis (CLPC). The purpose of this study was to study eotaxin-1 expression in the tears of long-term CL wearers. PATIENTS AND METHODS: Tears were collected with glass capillaries from 15 patients (2 male, 13 female) with various degree of CLPC at 2-year intervals. CLPC severity was graded from 0 to 4 with reference to standard slit-lamp photographs of the superior tarsal conjunctiva. The eotaxin-1 level in the tears was measured by an ELISA, using mouse anti-human eotaxin monoclonal antibodies. RESULTS: The mean age was 32.5 ± 13.3 years (range: 17 - 69 years). The mean interval between the tear collections was 30 ± 4.8 months. The mean concentration of eotaxin was 2150 ± 477 pg/mL and 2486 ± 810 pg/mL for the first and second series, respectively. The difference was not statistically significant (paired Wilcoxon/Kruskal-Wallis, p = 0.803). The mean score of papilla grade was 1.26 ± 0.18 for the first sample and 1.40 ± 0.19 two years later. There was no significant difference of grading between the two time periods (paired Wilcoxon/Kruskal-Wallis, p = 0.751). CONCLUSIONS: the eotaxin-1 level remains up-regulated over a long time period in patients wearing CL, most of them with chronic CLPC. Eotaxin may play a role in the pathogenesis of contact lens intolerance.

The link between land-use management and fluvial flood risk : a chaotic conception?

There is much policy interest in the possible linkages that might exist between land use and downstream fluvial flood risk. On the one hand, this position is sustained by observations from plot- and field-scale studies that suggest land management does affect runoff. On the other, upscaling these effects to show that land-management activities impact upon flood risk at larger catchment scales has proved to be elusive. This review considers the reasons for why this upscaling is problematic. We argue that, rather than it reflecting methodological challenges associated with the difficulties of modelling hydrological processes over very large areas and during extreme runoff events, it reflects the fact that any linkage between land management and flood risk cannot be generalized and taken out of its specific spatial (catchment) and temporal (flood event) context. We use Sayer's (1992) notion of a `chaotic conception' to describe the belief that there is a simple and general association between land management and downstream flood risk rather than the impacts of land management being spatially and temporally contingent in relation to the particular geographical location, time period and scale being considered. Our argument has important practical consequences because it implies that land-management activities to reduce downstream flood risk will be different to traditional flood-reduction interventions such as levees. The purpose of demonstration projects then needs careful consideration such that conclusions made for one project are not transferred uncritically to other scales of analysis or geographical locations.

The birth of the Rheic Ocean - Early Palaeozoic subsidence patterns and subsequent tectonic plate scenarios

New plate-tectonic reconstructions of the Gondwana margin suggest that the location of Gondwana-derived terranes should not only be guided by the models, but should also consider the possible detrital input from some Asian blocks (Hunia), supposed to have been located along the Cambrian Gondwana margin, and accreted in the Silurian to the North-Chinese block. Consequently, the Gondwana margin has to be subdivided into a more western domain, where the future Avalonian blocks will be separated from Gondwana by the opening Rheic Ocean, whereas in its eastern continuation, hosting the future basement areas of Central Europe, different periods of crustal extension should be distinguished. Instead of applying a rather cylindrical model, it is supposed that crustal extension follows a much more complex pattern, where local back-arcs or intra-continental rifts are involved. Guided by the age data of magmatic rocks and the pattern of subsidence curves, the following extensional events can be distinguished: During the early to middle Cambrian, a back-arc setting guided the evolution at the Gondwana margin. Contemporaneous intra-continental rift basins developed at other places related to a general post-PanAfrican extensional phase affecting Africa Upper Cambrian formation of oceanic crust is manifested in the Chamrousse area, and may have lateral cryptic relics preserved in other places. This is regarded as the oceanisation of some marginal basins in a context of back-arc rifting. These basins were closed in a mid-Ordovician tectonic phase, related to the subduction of buoyant material (mid-ocean ridge?) Since the Early Ordovician, a new phase of extension is observed, accompanied by a large-scale volcanic activity, erosion of the rift shoulders generated detritus (Armorican Quartzite) and the rift basins collected detrital zircons from a wide hinterland. This phase heralded the opening of Palaeotethys, but it failed due to the Silurian collision (Eo-Variscan phase) of an intra-oceanic arc with the Gondwana margin. During this time period, at the eastern wing of the Gondwana margin begins the drift of the future Hunia microcontinents, through the opening of an eastern prolongation of the already existing Rheic Ocean. The passive margin of the remaining Gondwana was composed of the Galatian superterranes, constituents of the future Variscan basement areas. Remaining under the influence of crustal extension, they will start their drift to Laurussia since the earliest Devonian during the opening of the Palaeotethys Ocean. (C) 2008 Elsevier B.V. All rights reserved.

Overlapping Pathways to Transplant Glomerulopathy: Chronic Humoral Rejection, Hepatitis C Infection and Thrombotic Microangiopathy

Background:Transplant glomerulopathy (TG) has received much attention in recent years as a manifestation of chronic humoral rejection (CHR). However, many cases lack C4d deposition and/or circulating donor-specifi c antibodies, and the contribution of other potential causes has not been fully addressed.Methods: Of 209 consecutive renal allograft indication biopsies performed for chronic allograft dysfunction, 25 that met pathologic criteria of TG (>10% duplication of the GBM without immune complex deposition) were examined for various etiologies, including hepatitis C infection (HCV), thrombotic microangiopathy (TMA), and CHR. 29 cases of biopsy-proven isolated chronic calcineurin inhibitor toxicity from the same time period were used as controls for comparing the prevalence of HCV.Results: Three partially overlapping categories accounted for 84% of the cases: C4d+TG (48%), HCV+TG (36%) and TMA+TG (32%). The majority of TMA+ cases were HCV+ (63%) and the majority of HCV+ cases had TMA (56%). Donor specifi c antibodies were associated with C4d+TG (7/8 vs. 1/4 C4d-TG; P<0.02), but not with HCV+TG. The prevalence of HCV was higher in the TG group than in 29 control patients without TG (36% vs. 7%, P<0.01). HCV+TG patients developed allograft failure earlier than HCV-TG patients (67.2 ± 60.2 mo versus 153.4 ± 126.2 mo, P=0.02). On a multivariate analysis, out of HCV, TG and C4d, only HCV was found to be a signifi cant risk factor for a more rapid allograft loss.Conclusion: We conclude that TG is not a specifi c diagnosis, but a pattern of pathologic injury with 3 major overlapping pathways involving CHR, HCV infection and TMA. It is important to distinguish these mechanisms, as they may have differentprognostic and therapeutic implications.

Elemental (C/N ratios) and isotopic (δ15N(org), δ13C(org)) compositions of sedimentary organic matter from a high-altitude mountain lake (Meidsee, 2661 m a.s.l., Switzerland): Implications for Lateglacial and Holocene Alpine landscape evolution

The deposition of Late Pleistocene and Holocene sediments in the high-altitude lake Meidsee (located at an altitude of 2661 m a.s.l. in the Southwestern Alps) strikingly coincided with global ice-sheet and mountain-glacier decay in the Alpine forelands and the formation of perialpine lakes. Radiocarbon ages of bottom-core sediments point out (pre-) Holocene ice retreat below 2700 m a.s.l., at about 16, 13, 10, and 9 cal. kyr BP. The Meidsee sedimentary record therefore provides information about the high-altitude Alpine landscape evolution since the Late Pleistocene/Holocene deglaciation in the Swiss Southwestern Alps. Prior to 5 cal. kyr BP, the C/N ratio and the isotopic composition of sedimentary organic matter (delta N-15(org), delta C-13(org)) indicate the deposition of algal-derived organic matter with limited input of terrestrial organic matter. The early Holocene and the Holocene climatic optimum (between 7.0 and 5.5 cal. kyr BP) were characterized by low erosion (decreasing magnetic susceptibility, chi) and high content of organic matter (C-org > 13 wt.%), enriched in C-13(org) (>-18 parts per thousand) with a low C/N (similar to 10) ratio, typical of modern algal matter derived from in situ production. During the late Holocene, there was a long-term increasing contribution of terrestrial organic matter into the lake (C/N > 11), with maxima between 2.4 and 0.9 cal. kyr BP. A major environmental change took place 800 years ago, with an abrupt decrease in the relative contribution of terrestrial organic material into the lake compared with aquatic organic material which subsequently largely dominated (C/N drop from 16 to 10). Nonetheless, this event was marked by a rise in soil erosion (chi), in nutrients input (N and P contents) and in anthropogenic lead deposition, suggesting a human disturbance of Alpine ecosystems 800 years ago. Indeed, this time period coincided with the migration of the Walser Alemannic people in the region, who settled at relatively high altitude in the Southwestern Alps for farming and maintaining Alpine passes.

Comparison of cannabinoid concentrations in oral fluid and whole blood between occasional and regular cannabis smokers prior to and after smoking a cannabis joint.

A cross-over controlled administration study of smoked cannabis was carried out on occasional and heavy smokers. The participants smoked a joint (11 % Δ9-tetrahydrocannabinol (THC)) or a matching placebo on two different occasions. Whole blood (WB) and oral fluid (OF) samples were collected before and up to 3.5 h after smoking the joints. Pharmacokinetic analyses were obtained from these data. Questionnaires assessing the subjective effects were administered to the subjects during each session before and after the smoking time period. THC, 11-hydroxy-THC (11-OH-THC) and 11-nor-9-carboxy-THC (THCCOOH) were analyzed in the blood by gas chromatography or liquid chromatography (LC)-tandem mass spectrometry (MS/MS). The determination of THC, THCCOOH, cannabinol (CBN), and Δ9-tetrahydrocannabinolic acid A (THC-A) was carried out on OF only using LC-MS/MS. In line with the widely accepted assumption that cannabis smoking results in a strong contamination of the oral cavity, we found that THC, and also THC-A, shows a sharp, high concentration peak just after smoking, with a rapid decrease in these levels within 3 h. No obvious differences were found between both groups concerning THC median maximum concentrations measured either in blood or in OF; these levels were equal to 1,338 and 1,041 μg/L in OF and to 82 and 94 μg/L in WB for occasional and heavy smokers, respectively. The initial WB THCCOOH concentration was much higher in regular smokers than in occasional users. Compared with the occasional smokers, the sensation of confusion felt by the regular smokers was much less while the feeling of intoxication remained almost unchanged.

Do Objective Measures of Blood Alcohol Concentrations Make More Sense than Self-reports in Emergency Department Studies?

Purpose: Concerns about self-reports have led to calls for objective measures of blood alcohol concentration (BAC). The present study compared objective measures with self-reports. Methods: BAC from breath or blood samples were obtained from 272 randomly sampled injured patients who were admitted to a Swiss emergency department (ED). Self-reports were compared a) between those providing and refusing a BAC test, and b) to estimated peak BAC (EPBAC) values based on BACs using the Widmark formula. Results: Those providing BACs were significantly (P < 0.05) younger, more often male, and less often reported alcohol consumption before injury, but consumed higher quantities when drinking. Eighty-eight percent of those with BAC measures gave consistent reports (positive or negative). Significantly more patients reported consumption with negative BAC measures (N = 29) than vice versa (N = 3). Duration of consumption and times between injury and BAC measurement predicted EPBAC better than did the objective BAC measure. Conclusions: There is little evidence that patients who provide objective BAC measures deliberately conceal consumption. ED studies must rely on self-reports, eg, take the time period between injury and ED admission into account. Clearly, objective measures are of clinical relevance, eg, to provide optimal treatment in the ED. However, they may be less relevant to establishing effects in an epidemiologic sense, such as estimating risk relationships. In this respect, efforts to increase the validity and reliability of self-reports should be preferred over the collection of additional objective measures.

The Role of Transnational Elites in shaping the evolving Field of Internet Governance

La gouvernance de l'Internet est une thématique récente dans la politique mondiale. Néanmoins, elle est devenue au fil des années un enjeu économique et politique important. La question a même pris une importance particulière au cours des derniers mois en devenant un sujet d'actualité récurrent. Forte de ce constat, c ette recherche retrace l'histoire de la gouvernance de l'Internet depuis son émergence comme enjeu politique dans les années 1980 jusqu'à la fin du Sommet Mondial sur la Société de l'Information (SMSI) en 2005. Plutôt que de se focaliser sur l'une ou l'autre des institutions impliquées dans la régulation du réseau informatique mondial, cette recherche analyse l'émergence et l'évolution historique d'un espace de luttes rassemblant un nombre croissant d'acteurs différents. Cette évolution est décrite à travers le prisme de la relation dialectique entre élites et non-élites et de la lutte autour de la définition de la gouvernance de l'Internet. Cette thèse explore donc la question de comment les relations au sein des élites de la gouvernance de l'Internet et entre ces élites et les non-élites expliquent l'emergence, l'évolution et la structuration d'un champ relativement autonome de la politique mondiale centré sur la gouvernance de l'Internet. Contre les perspectives dominantes réaliste et libérales, cette recherche s'ancre dans une approche issue de la combinaison des traditions hétérodoxes en économie politique internationale et des apports de la sociologie politique internationale. Celle-ci s'articule autour des concepts de champ, d'élites et d'hégémonie. Le concept de champ, développé par Bourdieu inspire un nombre croissant d'études de la politique mondiale. Il permet à la fois une étude différenciée de la mondialisation et l'émergence d'espaces de lutte et de domination au niveau transnational. La sociologie des élites, elle, permet une approche pragmatique et centrée sur les acteurs des questions de pouvoir dans la mondialisation. Cette recherche utilise plus particulièrement le concept d'élite du pouvoir de Wright Mills pour étudier l'unification d'élites a priori différentes autour de projets communs. Enfin, cette étude reprend le concept néo-gramscien d'hégémonie afin d'étudier à la fois la stabilité relative du pouvoir d'une élite garantie par la dimension consensuelle de la domination, et les germes de changement contenus dans tout ordre international. A travers l'étude des documents produits au cours de la période étudiée et en s'appuyant sur la création de bases de données sur les réseaux d'acteurs, cette étude s'intéresse aux débats qui ont suivi la commercialisation du réseau au début des années 1990 et aux négociations lors du SMSI. La première période a abouti à la création de l'Internet Corporation for Assigned Names and Numbers (ICANN) en 1998. Cette création est le résultat de la recherche d'un consensus entre les discours dominants des années 1990. C'est également le fruit d'une coalition entre intérêts au sein d'une élite du pouvoir de la gouvernance de l'Internet. Cependant, cette institutionnalisation de l'Internet autour de l'ICANN excluait un certain nombre d'acteurs et de discours qui ont depuis tenté de renverser cet ordre. Le SMSI a été le cadre de la remise en cause du mode de gouvernance de l'Internet par les États exclus du système, des universitaires et certaines ONG et organisations internationales. C'est pourquoi le SMSI constitue la seconde période historique étudiée dans cette thèse. La confrontation lors du SMSI a donné lieu à une reconfiguration de l'élite du pouvoir de la gouvernance de l'Internet ainsi qu'à une redéfinition des frontières du champ. Un nouveau projet hégémonique a vu le jour autour d'éléments discursifs tels que le multipartenariat et autour d'insitutions telles que le Forum sur la Gouvernance de l'Internet. Le succès relatif de ce projet a permis une stabilité insitutionnelle inédite depuis la fin du SMSI et une acceptation du discours des élites par un grand nombre d'acteurs du champ. Ce n'est que récemment que cet ordre a été remis en cause par les pouvoirs émergents dans la gouvernance de l'Internet. Cette thèse cherche à contribuer au débat scientifique sur trois plans. Sur le plan théorique, elle contribue à l'essor d'un dialogue entre approches d'économie politique mondiale et de sociologie politique internationale afin d'étudier à la fois les dynamiques structurelles liées au processus de mondialisation et les pratiques localisées des acteurs dans un domaine précis. Elle insiste notamment sur l'apport de les notions de champ et d'élite du pouvoir et sur leur compatibilité avec les anlayses néo-gramsciennes de l'hégémonie. Sur le plan méthodologique, ce dialogue se traduit par une utilisation de méthodes sociologiques telles que l'anlyse de réseaux d'acteurs et de déclarations pour compléter l'analyse qualitative de documents. Enfin, sur le plan empirique, cette recherche offre une perspective originale sur la gouvernance de l'Internet en insistant sur sa dimension historique, en démontrant la fragilité du concept de gouvernance multipartenaire (multistakeholder) et en se focalisant sur les rapports de pouvoir et les liens entre gouvernance de l'Internet et mondialisation. - Internet governance is a recent issue in global politics. However, it gradually became a major political and economic issue. It recently became even more important and now appears regularly in the news. Against this background, this research outlines the history of Internet governance from its emergence as a political issue in the 1980s to the end of the World Summit on the Information Society (WSIS) in 2005. Rather than focusing on one or the other institution involved in Internet governance, this research analyses the emergence and historical evolution of a space of struggle affecting a growing number of different actors. This evolution is described through the analysis of the dialectical relation between elites and non-elites and through the struggle around the definition of Internet governance. The thesis explores the question of how the relations among the elites of Internet governance and between these elites and non-elites explain the emergence, the evolution, and the structuration of a relatively autonomous field of world politics centred around Internet governance. Against dominant realist and liberal perspectives, this research draws upon a cross-fertilisation of heterodox international political economy and international political sociology. This approach focuses on concepts such as field, elites and hegemony. The concept of field, as developed by Bourdieu, is increasingly used in International Relations to build a differentiated analysis of globalisation and to describe the emergence of transnational spaces of struggle and domination. Elite sociology allows for a pragmatic actor-centred analysis of the issue of power in the globalisation process. This research particularly draws on Wright Mill's concept of power elite in order to explore the unification of different elites around shared projects. Finally, this thesis uses the Neo-Gramscian concept of hegemony in order to study both the consensual dimension of domination and the prospect of change contained in any international order. Through the analysis of the documents produced within the analysed period, and through the creation of databases of networks of actors, this research focuses on the debates that followed the commercialisation of the Internet throughout the 1990s and during the WSIS. The first time period led to the creation of the Internet Corporation for Assigned Names and Numbers (ICANN) in 1998. This creation resulted from the consensus-building between the dominant discourses of the time. It also resulted from the coalition of interests among an emerging power elite. However, this institutionalisation of Internet governance around the ICANN excluded a number of actors and discourses that resisted this mode of governance. The WSIS became the institutional framework within which the governance system was questioned by some excluded states, scholars, NGOs and intergovernmental organisations. The confrontation between the power elite and counter-elites during the WSIS triggered a reconfiguration of the power elite as well as a re-definition of the boundaries of the field. A new hegemonic project emerged around discursive elements such as the idea of multistakeholderism and institutional elements such as the Internet Governance Forum. The relative success of the hegemonic project allowed for a certain stability within the field and an acceptance by most non-elites of the new order. It is only recently that this order began to be questioned by the emerging powers of Internet governance. This research provides three main contributions to the scientific debate. On the theoretical level, it contributes to the emergence of a dialogue between International Political Economy and International Political Sociology perspectives in order to analyse both the structural trends of the globalisation process and the located practices of actors in a given issue-area. It notably stresses the contribution of concepts such as field and power elite and their compatibility with a Neo-Gramscian framework to analyse hegemony. On the methodological level, this perspective relies on the use of mixed methods, combining qualitative content analysis with social network analysis of actors and statements. Finally, on the empirical level, this research provides an original perspective on Internet governance. It stresses the historical dimension of current Internet governance arrangements. It also criticise the notion of multistakeholde ism and focuses instead on the power dynamics and the relation between Internet governance and globalisation.

The evolution of trans-generational altruism: kin selection meets niche construction.

A cornerstone result of sociobiology states that limited dispersal can induce kin competition to offset the kin selected benefits of altruism. Several mechanisms have been proposed to circumvent this dilemma but all assume that actors and recipients of altruism interact during the same time period. Here, this assumption is relaxed and a model is developed where individuals express an altruistic act, which results in posthumously helping relatives living in the future. The analysis of this model suggests that kin selected benefits can then feedback on the evolution of the trait in a way that promotes altruistic helping at high rates under limited dispersal. The decoupling of kin competition and kin selected benefits results from the fact that by helping relatives living in the future, an actor is helping individuals that are not in direct competition with itself. A direct consequence is that behaviours which actors gain by reducing the common good of present and future generations can be opposed by kin selection. The present model integrates niche-constructing traits with kin selection theory and delineates demographic and ecological conditions under which altruism can be selected for; and conditions where the 'tragedy of the commons' can be reduced.

Nosocomial nontyphoidal salmonellosis after antineoplastic chemotherapy: reactivation of asymptomatic colonization?

An increased frequency of nontyphoidal salmonellosis is well established in cancer patients, but it is unclear whether this represents increased susceptibility to exogenous infection or opportunistic, endogenous reactivation of asymptomatic carriage. In a retrospective study, a simple case definition was used to identify the probable presence of reactivation salmonellosis in five cancer patients between 1996 and 2002. Reactivation salmonellosis was defined as the development of nosocomial diarrhea >72 h after admission and following the administration of antineoplastic chemotherapy in an HIV-seronegative cancer patient who was asymptomatic on admission, in the absence of epidemiological evidence of a nosocomial outbreak. Primary salmonellosis associated with unrecognized nosocomial transmission or community acquisition and an unusually prolonged incubation period could not entirely be ruled out. During the same time period, another opportunistic infection, Pneumocystis pneumonia, was diagnosed in six cancer patients. Presumably, asymptomatic intestinal Salmonella colonization was converted to invasive infection by chemotherapy-associated intestinal mucosal damage and altered innate immune mechanisms. According to published guidelines, stool specimens from patients hospitalized for longer than 72 h should be rejected unless the patient is neutropenic or >or=65 years old with significant comorbidity. However, in this study neutropenia was present in only one patient, and four patients were <65 years old. Guidelines should thus be revised in order not to reject stool culture specimens from such patients. In cancer patients, nosocomial salmonellosis can occur as a chemotherapy-triggered opportunistic reactivation infection that may be similar in frequency to Pneumocystis pneumonia.

Long-term continuous-flow left ventricular assist devices (LVAD) as bridge to heart transplantation.

Heart transplantation (HTx) is the treatment of choice for end-stage heart failure but the limited availability of heart's donors still represents a major issue. So long-term mechanical circulatory support (MCS) has been proposed as an alternative treatment option to assist patients scheduled on HTx waiting list bridging them for a variable time period to cardiac transplantation-the so-called bridge-to-transplantation (BTT) strategy. Nowadays approximately 90% of patients being considered for MCS receive a left ventricular assist device (LVAD). In fact, LVAD experienced several improvements in the last decade and the predominance of continuous-flow over pulsatile-flow technology has been evident since 2008. The aim of the present report is to give an overview of continuous-flow LVAD utilization in the specific setting of the BTT strategy taking into consideration the most representative articles of the scientific literature and focusing the attention on the evolution, clinical outcomes, relevant implications on the HTx strategy and future perspectives of the continuous-flow LVAD technology.