887 resultados para four-pi detectors


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OBJECTIVES: Genomewide association studies (GWAS) have identified clear evidence of genetic markers for nicotine dependence. Other smoking phenotypes have been tested, but the results are less consistent. The tendency to relapse versus the ability to maintain long-term abstinence has received little attention in genetic studies; thus, our aim was to provide a better biological understanding of this phenotype through the identification of genetic loci associated with smoking relapse. METHODS: We carried out a GWAS on data from two European population-based collections, including a total of 835 cases (relapsers) and 990 controls (abstainers). Top-ranked findings from the discovery phase were tested for replication in two additional independent European population-based cohorts. RESULTS: Of the seven top markers from the discovery phase, none were consistently associated with smoking relapse across all samples and none reached genomewide significance. A single-nucleotide polymorphism rs1008509, within the Xylosyltransferase II (XYLT2) gene, was suggestively associated with smoking relapse in the discovery phase (β=-0.504; P=5.6E-06) and in the first replication sample (ALSPAC) (β=-0.27; P=0.004; n=1932), but not in the second sample (KORA) (β=0.19; P=0.138; n=912). We failed to identify an association between loci implicated previously in other smoking phenotypes and smoking relapse. CONCLUSION: Although no genomewide significant findings emerged from this study, we found that loci implicated in other smoking phenotypes were not associated with smoking relapse, which suggests that the neurobiology of smoking relapse and long-term abstinence may be distinct from biological mechanisms implicated in the development of nicotine dependence.

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PURPOSE: Self-administered questionnaires continue to be the most widely used type of physical activity assessment in epidemiological studies. However, test-retest reliability and validity of physical activity questionnaires have to be determined. In this study, three short physical activity questionnaires already used in Switzerland and the International Physical Activity Questionnaire (IPAQ) were validated. METHODS: Test-retest reliability was assessed by repeated administration of all questionnaires within 3 wk in 178 volunteers (77 women, 46.1+/-14.8 yr; 101 men 46.8+/-13.2 yr). Validity of categorical and continuous data was studied in a subsample of 35 persons in relation to 7-d accelerometer readings, percent body fat, and cardiorespiratory fitness. RESULTS: Reliability was fair to good with a Spearman correlation coefficient range of 0.43-0.68 for measures of continuous data and moderate to fair with Kappa values between 0.32 and 0.46 for dichotomous measures active/inactive. Total physical activity reported in the IPAQ and the Office in Motion Questionnaire (OIMQ) correlated with accelerometry readings (r=0.39 and 0.44, respectively). In contrast, correlations of self-reported physical data with percent body fat and cardiorespiratory fitness were low (r=-0.26-0.29). Participants categorized as active by the Swiss HEPA Survey 1999 instrument (HEPA99) accumulated significantly more days of the recommended physical activities than their inactive counterparts (4.4 and 2.7 d.wk, respectively, P<0.05). However, compared with accelerometer data, vigorous physical activities were overreported in investigated questionnaires. CONCLUSION: Collecting valid data on physical activity remains a challenging issue for questionnaire surveys. The IPAQ and the three other questionnaires are characterized to inform decisions about their appropriate use.

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Rapport de SynthèseLa thérapie antirétrovirale a progressée de manière significative depuis te début de l'épidémie du syndrome d'immunodéficience acquise (SIDA). Durant les 20 dernières années, plusieurs combinaisons de traitements ont été utilisées avec succès menant à une réduction de la mortalité associée. Par contre, le traitement a aussi engendré des cas de résistances multiples avec comme résultat, le besoin d'utiliser plusieurs molécules en combinaison, et une augmentation des cas de toxicité. Une stratégie souvent employée fût la combinaison de deux molécules inhibitrices de la protéase en même temps en combinaison avec une troisième molécule, le ritonavir. (DBPI).La cohorte Suisse sur le VIH existe depuis 1987 et permet d'étudier de façon longitudinale les patients qui y sont inscrits. Pour ce travail de thèse, nous avons étudié les patients inscrits à la cohorte suisse de 1996 à 2007 qui ont reçu une combinaison DBPI.Pendant la période étudiée, un total de 405 patients ont reçu un traitement DBPI, dont 295 patients ont reçu le DBPI pour plus de 6 mois. La durée médiane du traitement était de 2.2 ans. Sur les 287 patients qui étaient en échec viral au début du traitement (défini comme HIV RNA>400 copies/ml), 64.1% ont réussi à supprimer la virémie et 54.4% ont eu une suppression dans les 24 semaines qui ont suivi le début de la thérapie. Les patients avaient reçu en moyenne 6 combinaisons de traitement différentes avant le début de la thérapie DBPi. Pour les patients qui ont arrêté le traitement DBPI, la cause principale de l'arrêt était due au souhait du patient (48.3%), à l'échec virologique (22.5%) et à la toxicité (15.8%). Les patients ayant reçu le traitement après 1999, ou ayant été traités avec une combinaison de Lopinavir-ritonvir/saquinavir ou lopinavir-ritonavir/atazanavir arrivaient à supprimer leur virémie plus souvent que ceux qui avaient reçu d'autres combinaisons.Cette étude constitue la plus grande étude publiée sur le sujet de l'utilisation des DBPI pour les patients à résistances multiples. Malgré le fait que c'est une étude observationnelle, nous pouvons attester que le taux de succès était de 64.4%, le taux de toxicité était relativement bas (15.8%) et que la plus part des patients ont toléré ces combinaisons, malgré le taux élevé d'effets secondaires souvent rapportés. En somme, cette approche pourrait être envisagée dans des situations ou les nouveaux traitements tels que les inhibiteurs de l'intégrase et du CCR5 ne sont pas encore disponibles.

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SUMMARY This paper analyses the outcomes of the EEA and bilateral agreements vote at the level of the 3025 communities of the Swiss Confederation by simultaneously modelling the vote and the participation decisions. Regressions include economic and political factors. The economic variables are the aggregated shares of people employed in the losing, Winning and neutral sectors, according to BRUNETTI, JAGGI and WEDER (1998) classification, Which follows a Ricardo-Viner logic, and the average education levels, which follows a Heckscher-Ohlin approach. The political factors are those used in the recent literature. The results are extremely precise and consistent. Most of the variables have the predicted sign and are significant at the l % level. More than 80 % of the communities' vote variance is explained by the model, substantially reducing the residuals when compared to former studies. The political variables do have the expected signs and are significant as Well. Our results underline the importance of the interaction between electoral choice and participation decisions as well as the importance of simultaneously dealing with those issues. Eventually they reveal the electorate's high level of information and rationality. ZUSAMMENFASSUNG Unser Beitrag analysiert in einem Model, welches gleichzeitig die Stimm- ("ja" oder "nein") und Partizipationsentscheidung einbezieht, den Ausgang der Abstimmungen über den Beitritt zum EWR und über die bilateralen Verträge für die 3025 Gemeinden der Schweiz. Die Regressionsgleichungen beinhalten ökonomische und politische Variabeln. Die ökonomischen Variabeln beinhalten die Anteile an sektoriellen Arbeitsplatzen, die, wie in BRUNETTI, JAGGIl.1I1d WEDER (1998), in Gewinner, Verlierer und Neutrale aufgeteilt Wurden, gemäß dem Model von Ricardo-Viner, und das durchschnittliche Ausbildungsniveau, gemäß dem Model von Heckscher-Ohlin. Die politischen Variabeln sind die in der gegenwärtigen Literatur üblichen. Unsere Resultate sind bemerkenswert präzise und kohärent. Die meisten Variabeln haben das von der Theorie vorausgesagte Vorzeichen und sind hoch signifikant (l%). Mehr als 80% der Varianz der Stimmabgabe in den Gemeinden wird durch das Modell erklärt, was, im Vergleich mit früheren Arbeiten, die unerklärten Residuen Wesentlich verkleinert. Die politischen Variabeln haben auch die erwarteten Vorzeichen und sind signifikant. Unsere Resultate unterstreichen die Bedeutung der Interaktion zwischen der Stimm- und der Partizipationsentscheidung, und die Bedeutung diese gleichzeitig zu behandeln. Letztendlich, belegen sie den hohen lnformationsgrad und die hohe Rationalität der Stimmbürger. RESUME Le présent article analyse les résultats des votations sur l'EEE et sur les accords bilatéraux au niveau des 3025 communes de la Confédération en modélisant simultanément les décisions de vote ("oui" ou "non") et de participation. Les régressions incluent des déterminants économiques et politiques. Les déterminants économiques sont les parts d'emploi sectoriels agrégées en perdants, gagnants et neutres selon la classification de BRUNETTI, JAGGI ET WEDER (1998), suivant la logique du modèle Ricardo-Viner, et les niveaux de diplômes moyens, suivant celle du modèle Heckscher-Ohlin. Les déterminants politiques suivent de près ceux utilisés dans la littérature récente. Les résultats sont remarquablement précis et cohérents. La plupart des variables ont les signes prédits par les modèles et sont significatives a 1%. Plus de 80% de la variance du vote par commune sont expliqués par le modèle, faisant substantiellement reculer la part résiduelle par rapport aux travaux précédents. Les variables politiques ont aussi les signes attendus et sont aussi significatives. Nos résultats soulignent l'importance de l'interaction entre choix électoraux et décisions de participation et l'importance de les traiter simultanément. Enfin, ils mettent en lumière les niveaux élevés d'information et de rationalité de l'électorat.

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Référence bibliographique : Rol, 56982

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The most frequently used method to demonstrate testosterone abuse is the determination of the testosterone and epitestosterone concentration ratio (T/E ratio) in urine. Nevertheless, it is known that factors other than testosterone administration may increase the T/E ratio. In the last years, the determination of the carbon isotope ratio has proven to be the most promising method to help discriminate between naturally elevated T/E ratios and those reflecting T use. In this paper, an excretion study following oral administration of 40 mg testosterone undecanoate initially and 13 h later is presented. Four testosterone metabolites (androsterone, etiocholanolone, 5 alpha-androstanediol, and 5 beta-androstanediol) together with an endogenous reference (5 beta-pregnanediol) were extracted from the urines and the delta(13)C/(12)C ratio of each compound was analyzed by gas chromatography-combustion-isotope ratio mass spectrometry. The results show similar maximum delta(13)C-value variations (parts per thousand difference of delta(13)C/(12)C ratio from the isotope ratio standard) for the T metabolites and concomitant changes of the T/E ratios after administration of the first and the second dose of T. Whereas the T/E ratios as well as the androsterone, etiocholanolone and 5 alpha-androstanediol delta(13)C-values returned to the baseline 15 h after the second T administration, a decrease of the 5 beta-androstanediol delta-values could be detected for over 40 h. This suggests that measurements of 5 beta-androstanediol delta-values allow the detection of a testosterone ingestion over a longer post-administration period than other T metabolites delta(13)C-values or than the usual T/E ratio approach.

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Four methods were tested to assess the fire-blight disease response on grafted pear plants. The leaves of the plants were inoculated with Erwinia amylovora suspensions by pricking with clamps, cutting with scissors, local infiltration, and painting a bacterial suspension onto the leaves with a paintbrush. The effects of the inoculation methods were studied in dose-time-response experiments carried out in climate chambers under quarantine conditions. A modified Gompertz model was used to analyze the disease-time relatiobbnships and provided information on the rate of infection progression (rg) and time delay to the start of symptoms (t0). The disease-pathogen-dose relationships were analyzed according to a hyperbolic saturation model in which the median effective dose (ED50) of the pathogen and maximum disease level (ymax) were determined. Localized infiltration into the leaf mesophile resulted in the early (short t0) but slow (low rg) development of infection whereas in leaves pricked with clamps disease symptoms developed late (long t0) but rapidly (high rg). Paintbrush inoculation of the plants resulted in an incubation period of medium length, a moderate rate of infection progression, and low ymax values. In leaves inoculated with scissors, fire-blight symptoms developed early (short t0) and rapidly (high rg), and with the lowest ED50 and the highest ymax

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By use of a respiration chamber, 24-hour energy expenditure (EE), diet-induced thermogenesis (DIT), and basal and sleeping EE were measured in 20 young rural Gambian men during the "hungry" season (weight, 60.8 +/- 1.4 kg) and in a group of 16 European men matched for body composition (weight, 66.9 +/- 1.9 kg). The 24-h EE was lower in Gambian than in European men (2047 +/- 46 vs 2635 +/- 74 kcal/d, p less than 0.001, respectively). Basal EE and sleeping EE were also lower in Gambian than in European men (1.05 +/- 0.02 vs 1.25 +/- 0.02 kcal/min and 1.0 +/- 0.02 vs 1.18 +/- 0.02 kcal/min, p less than 0.01, respectively). DIT was blunted in Gambian compared with European men (6.3 +/- 0.6% vs 12.1 +/- 0.5%, p less than 0.001 respectively). The net efficiency of walking was greater in Gambian than in European men (23.2 +/- 0.3% vs 20.1 +/- 0.4%, p less than 0.001, respectively). A low basal and sleeping EE, a reduced DIT, and a high work efficiency are important energy-sparing mechanisms in Gambian men, which allow them to cope with a marginal level of dietary intake during the hungry season.

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A simple extended finite field nuclear relaxation procedure for calculating vibrational contributions to degenerate four-wave mixing (also known as the intensity-dependent refractive index) is presented. As a by-product one also obtains the static vibrationally averaged linear polarizability, as well as the first and second hyperpolarizability. The methodology is validated by illustrative calculations on the water molecule. Further possible extensions are suggested

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In hyperdiploid acute lymphoblastic leukaemia (ALL), the simultaneous occurrence of specific aneuploidies confers a more favourable outcome than hyperdiploidy alone. Interphase (I) FISH complements conventional cytogenetics (CC) through its sensitivity and ability to detect chromosome aberrations in non-dividing cells. To overcome the limits of manual I-FISH, we developed an automated four-colour I-FISH approach and assessed its ability to detect concurrent aneuploidies in ALL. I-FISH was performed using centromeric probes for chromosomes 4, 6, 10 and 17. Parameters established for automatic nucleus selection and signal detection were evaluated (3 controls). Cut-off values were determined (10 controls, 1000 nuclei/case). Combinations of aneuploidies were considered relevant when each aneuploidy was individually significant. Results obtained in 10 ALL patients (1500 nuclei/patient) were compared with those by CC. Various combinations of aneuploidies were identified. All clones detected by CC were observed by I-FISH. I-FISH revealed numerous additional abnormal clones, ranging between 0.1% and 31.6%, based on the large number of nuclei evaluated. Four-colour automated I-FISH permits the identification of concurrent aneuploidies of prognostic significance in hyperdiploid ALL. Large numbers of cells can be analysed rapidly by this method. Owing to its high sensitivity, the method provides a powerful tool for the detection of small abnormal clones at diagnosis and during follow up. Compared to CC, it generates a more detailed cytogenetic picture, the biological and clinical significance of which merits further evaluation. Once optimised for a given set of probes, the system can be easily adapted for other probe combinations.

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In many European countries, image quality for digital x-ray systems used in screening mammography is currently specified using a threshold-detail detectability method. This is a two-part study that proposes an alternative method based on calculated detectability for a model observer: the first part of the work presents a characterization of the systems. Eleven digital mammography systems were included in the study; four computed radiography (CR) systems, and a group of seven digital radiography (DR) detectors, composed of three amorphous selenium-based detectors, three caesium iodide scintillator systems and a silicon wafer-based photon counting system. The technical parameters assessed included the system response curve, detector uniformity error, pre-sampling modulation transfer function (MTF), normalized noise power spectrum (NNPS) and detective quantum efficiency (DQE). Approximate quantum noise limited exposure range was examined using a separation of noise sources based upon standard deviation. Noise separation showed that electronic noise was the dominant noise at low detector air kerma for three systems; the remaining systems showed quantum noise limited behaviour between 12.5 and 380 µGy. Greater variation in detector MTF was found for the DR group compared to the CR systems; MTF at 5 mm(-1) varied from 0.08 to 0.23 for the CR detectors against a range of 0.16-0.64 for the DR units. The needle CR detector had a higher MTF, lower NNPS and higher DQE at 5 mm(-1) than the powder CR phosphors. DQE at 5 mm(-1) ranged from 0.02 to 0.20 for the CR systems, while DQE at 5 mm(-1) for the DR group ranged from 0.04 to 0.41, indicating higher DQE for the DR detectors and needle CR system than for the powder CR phosphor systems. The technical evaluation section of the study showed that the digital mammography systems were well set up and exhibiting typical performance for the detector technology employed in the respective systems.

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Levels of support for just world beliefs among young adults (N = 598) from four ex-Yugoslavian countries-Bosnia and Herzegovina, Croatia, the former Yugoslav Republic of Macedonia, and Slovenia-were compared, taking into account victimization experiences and the general belief in a just world. Being a victim affected an individual's belief in a just world in the two less economically favored contexts: Victims of exclusion in Macedonia and victims of war in Bosnia and Herzegovina were less likely to believe in a just world than non-victims. These victimization variables partly explained why the mean scores of these two countries were less than those of the two others. A deleterious effect of cumulative negative events on belief in a just world was identified, in parallel with a lower endorsement of the belief when the first victimization occurred more recently.

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BACKGROUND: Four different types of internal hernias (IH) are known to occur after laparoscopic Roux-en-Y gastric bypass (LRYGBP) performed for morbid obesity. We evaluate multidetector row helical computed tomography (MDCT) features for their differentiation. METHODS: From a prospectively collected database including 349 patients with LRYGBP, 34 acutely symptomatic patients (28 women, mean age 32.6), operated on for IH immediately after undergoing MDCT, were selected. Surgery confirmed 4 (11.6%) patients with transmesocolic, 10 (29.4%) with Petersen's, 15 (44.2%) with mesojejunal, and 5 (14.8%) with jejunojejunal IH. In consensus, 2 radiologists analyzed 13 MDCT features to distinguish the four types of IH. Statistical significance was calculated (p < 0.05, Fisher's exact test, chi-square test). RESULTS: MDCT features of small bowel obstruction (SBO) (n = 25, 73.5%), volvulus (n = 22, 64.7%), or a cluster of small bowel loops (SBL) (n = 27, 79.4%) were inconsistently present and overlapped between the four IH. The following features allowed for IH differentiation: left upper quadrant clustered small bowel loops (p < 0.0001) and a mesocolic hernial orifice (p = 0.0003) suggested transmesocolic IH. SBL abutting onto the left abdominal wall (p = 0.0021) and left abdominal shift of the superior mesenteric vessels (SMV) (p = 0.0045) suggested Petersen's hernia. The SMV predominantly shifted towards the right anterior abdominal wall in mesojejunal hernia (p = 0.0033). Location of the hernial orifice near the distal anastomosis (p = 0.0431) and jejunojejunal suture widening (p = 0.0005) indicated jejunojejunal hernia. CONCLUSIONS: None of the four IH seems associated with a higher risk of SBO. Certain MDCT features, such as the position of clustered SBL and hernial orifice, help distinguish between the four IH and may permit straightforward surgery.