1000 resultados para Neyghborhood impact


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The purpose of this study was to investigate the impact of navigator timing on image quality in navigator-gated and real-time motion-corrected, free-breathing, three-dimensional (3D) coronary MR angiography (MRA) with submillimeter spatial image resolution. Both phantom and in vivo investigations were performed. 3D coronary MRA with real-time navigator technology was applied using variable navigator time delays (time delay between the navigator and imaging sequences) and varying spatial resolutions. Quantitative objective and subjective image quality parameters were assessed. For high-resolution imaging, reduced image quality was found as a function of increasing navigator time delay. Lower spatial resolution coronary MRA showed only minor sensitivity to navigator timing. These findings were consistent among volunteers and phantom experiments. In conclusion, for submillimeter navigator-gated and real-time motion-corrected 3D coronary MRA, shortening the time delay between the navigator and the imaging portion of the sequence becomes increasingly important for improved spatial resolution.

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Dans les sols infestés avec Macrophomina phaseolina les semences de niébé ne germent pas ou bien la plantule est détruite plus ou moins rapidement après la germination. Clonostachys rosea est un champignon commun du sol reconnu comme un saprophyte avec une haute capacité de compétition sur les racines et dans le sol. Notre étude a pour objectif d’évaluer l’effet de C. rosea en traitement de semences du niébé conservées à 40°C sur le développement de la pourriture charbonneuse. L’effet de la durée de conservation sur la viabilité des spores et le pouvoir antagonique du bioagent a également été étudié dans les conditions semi contrôlé et au champ. Les isolats de C. rosea proviennent de la collection du laboratoire de phytopathologie de AGRHYMET. La production des spores a été effectuée sur le milieu PDA pendant 4 semaines. Les semences du niébé ont été traitées avec une suspension de spores à la concentration de 108 spores / ml à raison de 5 ml de suspension par kg de semences. Les semences traitées ont été séchées sous la hotte à flux laminaire pendant 2 h avant d’être semées ou conservées à 40°C. Des tests de viabilité des spores de C. rosea sur le milieu de culture PDA ont été effectués au laboratoire tous les 15 jours de conservation. Le taux de germination des semences sur papier buvard, évalué au cinquième jour après semis au laboratoire a été de 99 %. La forte moyenne de spores viables au jour de l’enrobage (J0) (>4,5 105), a chuté à 1700 spores par graines après 75 jours de conservation. En serre, le niveau de colonisation des tissus des plants de niébé se développant sur le sol infesté a été significativement plus faible chez les plants issus de graines enrobées (1009 microsclérotes/g tissus) que chez ceux issus de graines non enrobées (2356 microsclérotes/g tissus). Par rapport a la sévérité de la maladie, exprimée sur une échelle de 1-5, ont été notées une forte infection des plants du témoin Macrophomina (graines non traitées semées dans un sol infesté) et des attaques moins sévères sur les traitements G3M et G4M (graines traitées semées dans un sol infesté). Au champ dans l’essai semé avec des graines enrobées mais non conservées, l’association des isolats G3 et G4 a été nettement supérieure aux autres traitements par rapport aux rendements en fane et en graines. Par contre, par rapport au rendement, aucun effet des traitements n’a été observé dans l’essai semé avec les graines conservées pendant 30 jours.

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One of the principle aims of the Working Families' Tax Credit in the UK was to increase the participation of single mothers. The literature to date concludes there was approximately a five-percentage-point increase in employment of single mothers. The differences-in-differences methodology that is typically used compares single mother with single women without children. However, the characteristics of these groups are very different, and change over time in relative covariates are likely to violate the identifying assumption. We find that when we control for differential trends between women with and without children, the employment effect of the policy falls significantly. Moreover, the effect is borne solely by those working full-time (30 hours or more), while having no effect on inducing people into the labor market from inactivity. Looking closely at important covariates over time, we can see sizeable changes in the relative returns to employment between the treatment and control groups.

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This paper studies the impact of a regional free trade agreement, MERCOSUR, on technologyupgrading by Argentinean firms. To guide empirical work, I introduce technology choice inMelitz s (2003) model of trade with heterogeneous firms. The joint treatment of the technologyadoption and exporting choices shows that the increase in revenues produced by trade integrationcan induce exporters to upgrade technology. An empirical test of the model reveals that firms inindustries facing higher reductions in Brazil s tariffs increase their investment in technologyfaster. The effect of tariffs on entry in the export market and technology adoption is highest inthe upper-middle range of the firm size distribution, as predicted by the model.

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PURPOSE: Even though there is evidence that both patients and oncology clinicians are affected by the quality of communication and that communication skills can be effectively trained, so-called Communication Skills Trainings (CSTs) remain heterogeneously implemented. METHODS: A systematic evaluation of the level of satisfaction of oncologists with the Swiss CST before (2000-2005) and after (2006-2012) it became mandatory. RESULTS: Levels of satisfaction with the CST were high, and satisfaction of physicians participating on a voluntary or mandatory basis did not significantly differ for the majority of the items. CONCLUSIONS: The evaluation of physicians' satisfaction over the years and after introduction of mandatory training supports recommendations for generalized implementation of CST and mandatory training for medical oncologists.

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BACKGROUND: The quality of colon cleansing is a major determinant of quality of colonoscopy. To our knowledge, the impact of bowel preparation on the quality of colonoscopy has not been assessed prospectively in a large multicenter study. Therefore, this study assessed the factors that determine colon-cleansing quality and the impact of cleansing quality on the technical performance and diagnostic yield of colonoscopy. METHODS: Twenty-one centers from 11 countries participated in this prospective observational study. Colon-cleansing quality was assessed on a 5-point scale and was categorized on 3 levels. The clinical indication for colonoscopy, diagnoses, and technical parameters related to colonoscopy were recorded. RESULTS: A total of 5832 patients were included in the study (48.7% men, mean age 57.6 [15.9] years). Cleansing quality was lower in elderly patients and in patients in the hospital. Procedures in poorly prepared patients were longer, more difficult, and more often incomplete. The detection of polyps of any size depended on cleansing quality: odds ratio (OR) 1.73: 95% confidence interval (CI)[1.28, 2.36] for intermediate-quality compared with low-quality preparation; and OR 1.46: 95% CI[1.11, 1.93] for high-quality compared with low-quality preparation. For polyps >10 mm in size, corresponding ORs were 1.0 for low-quality cleansing, OR 1.83: 95% CI[1.11, 3.05] for intermediate-quality cleansing, and OR 1.72: 95% CI[1.11, 2.67] for high-quality cleansing. Cancers were not detected less frequently in the case of poor preparation. CONCLUSIONS: Cleansing quality critically determines quality, difficulty, speed, and completeness of colonoscopy, and is lower in hospitalized patients and patients with higher levels of comorbid conditions. The proportion of patients who undergo polypectomy increases with higher cleansing quality, whereas colon cancer detection does not seem to critically depend on the quality of bowel preparation.

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We investigate whether the gender composition of teams affect theireconomic performance. We study a large business game, played in groups ofthree, where each group takes the role of a general manager. There are twoparallel competitions, one involving undergraduates and the other involvingMBAs. Our analysis shows that teams formed by three women aresignificantly outperformed by any other gender combination, both at theundergraduate and MBA levels. Looking across the performancedistribution, we find that for undergraduates, three women teams areoutperformed throughout, but by as much as 10pp at the bottom and by only1pp at the top. For MBAs, at the top, the best performing group is two menand one woman. The differences in performance are explained bydifferences in decision-making. We observe that three women teams are lessaggressive in their pricing strategies, invest less in R&D, and invest more insocial sustainability initiatives, than any other gender combination teams.Finally, we find support for the hypothesis that it is poor work dynamicsamong the three women teams that drives the results.

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This paper uses the ability to recall one s age correctly as an indicator of numeracy.We show that low levels of nutrition impaired numeracy in industrializing England, 1780-1850.Numeracy declined markedly among those born during the war years, especially where wheatwas dear. England s nascent welfare state mitigated the negative effect of high food prices oncognitive skills. Nutrition during early development mattered for labor market outcomes:individuals born in periods or countries with high age heaping were more likely to sort intooccupations with limited intellectual requirements.

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This study investigated the neural regions involved in blood pressure reactions to negative stimuli and their possible modulation by attention. Twenty-four healthy human subjects (11 females; age = 24.75 ± 2.49 years) participated in an affective perceptual load task that manipulated attention to negative/neutral distractor pictures. fMRI data were collected simultaneously with continuous recording of peripheral arterial blood pressure. A parametric modulation analysis examined the impact of attention and emotion on the relation between neural activation and blood pressure reactivity during the task. When attention was available for processing the distractor pictures, negative pictures resulted in behavioral interference, neural activation in brain regions previously related to emotion, a transient decrease of blood pressure, and a positive correlation between blood pressure response and activation in a network including prefrontal and parietal regions, the amygdala, caudate, and mid-brain. These effects were modulated by attention; behavioral and neural responses to highly negative distractor pictures (compared with neutral pictures) were smaller or diminished, as was the negative blood pressure response when the central task involved high perceptual load. Furthermore, comparing high and low load revealed enhanced activation in frontoparietal regions implicated in attention control. Our results fit theories emphasizing the role of attention in the control of behavioral and neural reactions to irrelevant emotional distracting information. Our findings furthermore extend the function of attention to the control of autonomous reactions associated with negative emotions by showing altered blood pressure reactions to emotional stimuli, the latter being of potential clinical relevance.

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ABSTRACT: BACKGROUND: The main objective of our study was to assess the impact of a board game on smoking status and smoking-related variables in current smokers. To accomplish this objective, we conducted a randomized controlled trial comparing the game group with a psychoeducation group and a waiting-list control group. METHODS: The following measures were performed at participant inclusion, as well as after a 2-week and a 3-month follow-up period: "Attitudes Towards Smoking Scale" (ATS-18), "Smoking Self-Efficacy Questionnaire" (SEQ-12), "Attitudes Towards Nicotine Replacement Therapy" scale (ANRT-12), number of cigarettes smoked per day, stages of change, quit attempts, and smoking status. Furthermore, participants were assessed for concurrent psychiatric disorders and for the severity of nicotine dependence with the Fagerström Test for Nicotine Dependence (FTND). RESULTS: A time × group effect was observed for subscales of the ANRT-12, ATS-18 and SEQ-12, as well as for the number of cigarettes smoked per day. At three months follow-up, compared to the participants allocated to the waiting list group, those on Pick-Klop group were less likely to remain smoker.Outcomes at 3 months were not predicted by gender, age, FTND, stage of change, or psychiatric disorders at inclusion. CONCLUSIONS: The board game seems to be a good option for smokers. The game led to improvements in variables known to predict quitting in smokers. Furthermore, it increased smoking-cessation rates at 3-months follow-up. The game is also an interesting alternative for smokers in the precontemplation stage.

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The objective of this study was to evaluate the intended and unintended impact on pharmaceutical use and sales of three public financing reforms applied to the prescription of statins: a Spanish generic reference pricing (RP) system for lovastatin and simvastatin, and two competing policies introduced by the Andalusian Public Health Service (APHS) for all statins, first a maximum consumer price (MCP) and then a so called quality prescribing incentive for general practitioners (MCP plus PI).This study is designed as an observational, retrospective, interrupted time series analysis with comparison series (APHS and the rest of Spain) of 46 monthly drug use and sales ratios from January 2001 to October 2004 for each active ingredient in the group of statins.RP has been effective at reducing the volume of sales growth of the off-patent statins, yet its overall impact on sales of all statins has been relatively modest. The quantity and volume of sales impact heavily depends on regulatory RP details such as when the system is introduced, how often it is updated, and how the reference price is calculated.

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In short space of time increase in temperature and rainfall can affect vector populations and, consequently, the diseases for them transmitted. The present study analyzed the effect of small temperature and humidity variations on the fecundity, fertility and survival of Aedes aegypti. These parameters were analyzed using individual females at temperatures ranging from 23 to 27 °C (mean 25 °C); 28 to 32 °C (mean 30 °C) and 33 to 37 °C (mean 35 ºC) associated to 60±8% and 80±6% relative humidity. Females responded to an increase in temperature by reducing egg production, oviposition time and changing oviposition patterns. At 25 ºC and 80% relative humidity, females survived two-fold more and produced 40% more eggs when compared to those kept at 35 ºC and 80% relative humidity. However, in 45% of females kept at 35 ºC and 60% relative humidity oviposition was inhibited and only 15% females laid more than 100 eggs, suggesting that the intensity of the temperature effect was influenced by humidity. Gradual reductions in egg fertility at 60% relative humidity were observed with the increase in temperature, although such effect was not found in the 80% relative humidity at 25 º C and 30 º C. These results suggest that the reduction in population densities recorded in tropical areas during seasons when temperatures reach over 35 ºC is likely to be strongly influenced by temperature and humidity, with a negative effect on several aspects of mosquito biology.

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The kidney is a key organ in the maintenance of ion and fluid homeostasis and specific transport systems localized along the nephron guarantee this function. Due to its large functional heterogeneity, experiments on the whole organ level cannot be easily performed, and thus more refined tools are needed, like for example the development of specific recombination systems to gain knowledge on the physiological role of single proteins implicated in ion transport. This review introduces the transgenic technology developed over the past decades, and then focuses on recent strategies for generating kidney-specific gene targeting, over-expression, and gene ablation in mice, that will help to understand the physiological role of proteins implicated in salt and water balance in the kidney.

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Reductions in firing costs are often advocated as a way of increasingthe dynamism of labour markets in both developed and less developed countries. Evidence from Europe and the U.S. on the impact of firing costs has, however, been mixed. Moreover, legislative changes both in Europe and the U.S. have been limited. This paper, instead, examines the impact of the Colombian Labour Market Reform of 1990, which substantially reduced dismissal costs. I estimate the incidence of a reduction in firing costs on worker turnover by exploiting the temporal change in the Colombian labour legislation as well as the variability in coverage between formal and informal sector workers. Using a grouping estimator to control for common aggregate shocks and selection, I find that the exit hazard rates into and out of unemployment increased after the reform by over 1% for formal workers (covered by the legislation) relative to informal workers (uncovered). The increase of the hazards implies a net decrease in unemployment of a third of a percentage point, which accounts for about one quarter of the fall in unemployment during the period of study.