862 resultados para power to moderate
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This paper studies price determination in pharmaceutical markets using data for 25 countries, six years and a comprehensive list of products from the MIDAS IMS database. We show that market power and the quality of the product has a significantly positive impact of prices. The nationality of the producer appears to have a small and often insignificant impact on prices, which suggests that countries which regulates prices have relatively little power to do it in a way that advances narrow national interest. We produce a theoretical explanation for this phenomenon based on the fact that low negotiated prices in a country would have a knock-on effect in other markets, and is thus strongly resisted by producers. Another key finding is that the U.S. has prices that are not significantly higher than those of countries with similar income levels. This, together with the former observation on the effect of the nationality of producers casts doubt on the ability of countries to purs
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The limited ability of common variants to account for the genetic contribution to complex disease has prompted searches for rare variants of large effect, to partly explain the 'missing heritability'. Analyses of genome-wide genotyping data have identified genomic structural variants (GSVs) as a source of such rare causal variants. Recent studies have reported multiple GSV loci associated with risk of obesity. We attempted to replicate these associations by similar analysis of two familial-obesity case-control cohorts and a population cohort, and detected GSVs at 11 out of 18 loci, at frequencies similar to those previously reported. Based on their reported frequencies and effect sizes (OR≥25), we had sufficient statistical power to detect the large majority (80%) of genuine associations at these loci. However, only one obesity association was replicated. Deletion of a 220 kb region on chromosome 16p11.2 has a carrier population frequency of 2×10(-4) (95% confidence interval [9.6×10(-5)-3.1×10(-4)]); accounts overall for 0.5% [0.19%-0.82%] of severe childhood obesity cases (P = 3.8×10(-10); odds ratio = 25.0 [9.9-60.6]); and results in a mean body mass index (BMI) increase of 5.8 kg.m(-2) [1.8-10.3] in adults from the general population. We also attempted replication using BMI as a quantitative trait in our population cohort; associations with BMI at or near nominal significance were detected at two further loci near KIF2B and within FOXP2, but these did not survive correction for multiple testing. These findings emphasise several issues of importance when conducting rare GSV association, including the need for careful cohort selection and replication strategy, accurate GSV identification, and appropriate correction for multiple testing and/or control of false discovery rate. Moreover, they highlight the potential difficulty in replicating rare CNV associations across different populations. Nevertheless, we show that such studies are potentially valuable for the identification of variants making an appreciable contribution to complex disease.
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BACKGROUND: Screening for obstructive sleep apnea (OSA) is recommended as part of the preoperative assessment of obese patients scheduled for bariatric surgery. The objective of this study was to compare the sensitivity of oximetry alone versus portable polygraphy in the preoperative screening for OSA. METHODS: Polygraphy (type III portable monitor) and oximetry data recorded as part of the preoperative assessment before bariatric surgery from 68 consecutive patients were reviewed. We compared the sensitivity of 3% or 4% desaturation index (oximetry alone) with the apnea-hypopnea index (AHI; polygraphy) to diagnose OSA and classify the patients as normal (<10 events per hour), mild to moderate (10-30 events per hour), or severe (>30 events per hour). RESULTS: Using AHI, the prevalence of OSA (AHI > 10 per hour) was 57.4%: 16.2% of the patients were classified as severe, 41.2% as mild to moderate, and 42.6% as normal. Using 3% desaturation index, 22.1% were classified as severe, 47.1% as mild to moderate, and 30.9% as normal. With 4% desaturation index, 17.6% were classified as severe, 32.4% as mild, and 50% as normal. Overall, 3% desaturation index compared to AHI yielded a 95% negative predictive value to rule out OSA (AHI > 10 per hour) and a 100% sensitivity (0.73 positive predictive value) to detect severe OSA (AHI > 30 per hour). CONCLUSIONS: Using oximetry with 3% desaturation index as a screening tool for OSA could allow us to rule out significant OSA in almost a third of the patients and to detect patients with severe OSA. This cheap and widely available technique could accelerate preoperative work-up of these patients.
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The relationship between metabolism and reactive oxygen species (ROS) production by the mitochondria has often been (wrongly) viewed as straightforward, with increased metabolism leading to higher generation of pro-oxidants. Insights into mitochondrial functioning show that oxygen consumption is principally coupled with either energy conversion as ATP or as heat, depending on whether the ATP-synthase or the mitochondrial uncoupling protein 1 (UCP1) is driving respiration. However, these two processes might greatly differ in terms of oxidative costs. We used a cold challenge to investigate the oxidative stress consequences of an increased metabolism achieved either by the activation of an uncoupled mechanism (i.e. UCP1 activity) in the brown adipose tissue (BAT) of wild-type mice or by ATP-dependent muscular shivering thermogenesis in mice deficient for UCP1. Although both mouse strains increased their metabolism by more than twofold when acclimatised for 4 weeks to moderate cold (12°C), only mice deficient for UCP1 suffered from elevated levels of oxidative stress. When exposed to cold, mice deficient for UCP1 showed an increase of 20.2% in plasmatic reactive oxygen metabolites, 81.8% in muscular oxidized glutathione and 47.1% in muscular protein carbonyls. In contrast, there was no evidence of elevated levels of oxidative stress in the plasma, muscles or BAT of wild-type mice exposed to cold despite a drastic increase in BAT activity. Our study demonstrates differing oxidative costs linked to the functioning of two highly metabolically active organs during thermogenesis, and advises careful consideration of mitochondrial functioning when investigating the links between metabolism and oxidative stress.
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Tissue parasitism, inflammatory process (histologic methods) and sympathetic denervation (glyoxylic acid-induced histofluorescence for demonstration of catecholamines) were studied in the heart (atrium and verntricle) and the submandibular gland of rats infected with the Y strain of Trypanosoma cruzi. In the heart paralleling intense parasitism and inflammatory process, the sympathetic denervation started at day 6 of infection and at the end of the acute phase (day 20) practically no varicose nerve terminals were found in both myocardium and vessels. In the submandibular gland, in spite of the rarity of anastigote pseudocysts and the scarcity of inflammatory foci, slight to moderate (days 13-15 of infection) or moderate to severe denervation (day 20) was found. At day 120 of infection both organs exhibited normal pattern of sympathetic innervation and only the heart showed some inflammatory foci and rare psudocysts (ventricle). Our data suggest the involvement of circulating factors in the sympathetic denervation phenomena but indicate that local inflammatory process is, at least, an aggravating factor.
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There is a general presumption that competition is a good thing. In this paper we show that competition in the insurance markets can be bad and that adverse selection is in general worse under competition than under monopoly. The reason is that monopoly can exploit its market power to relax incentive constraints by cross-subsidization between different risk types. Cream-skimming behavior, on the contrary, prevents competitive firms from using implicit transfers. In effect monopoly is shown to provide better coverage to those buying insurance but at the cost of limiting participation to insurance. Performing simulation for di erent distributions of risk, we find that monopoly in general performs (much) better than competition in terms of the realization of the gains from trade across all traders in equilibrium. However, most of the surplus is retained by the firm and, as a result, most individuals prefer competitive markets notwithstanding their performance is generally poorer than monopoly.
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1. Statistical modelling is often used to relate sparse biological survey data to remotely derived environmental predictors, thereby providing a basis for predictively mapping biodiversity across an entire region of interest. The most popular strategy for such modelling has been to model distributions of individual species one at a time. Spatial modelling of biodiversity at the community level may, however, confer significant benefits for applications involving very large numbers of species, particularly if many of these species are recorded infrequently. 2. Community-level modelling combines data from multiple species and produces information on spatial pattern in the distribution of biodiversity at a collective community level instead of, or in addition to, the level of individual species. Spatial outputs from community-level modelling include predictive mapping of community types (groups of locations with similar species composition), species groups (groups of species with similar distributions), axes or gradients of compositional variation, levels of compositional dissimilarity between pairs of locations, and various macro-ecological properties (e.g. species richness). 3. Three broad modelling strategies can be used to generate these outputs: (i) 'assemble first, predict later', in which biological survey data are first classified, ordinated or aggregated to produce community-level entities or attributes that are then modelled in relation to environmental predictors; (ii) 'predict first, assemble later', in which individual species are modelled one at a time as a function of environmental variables, to produce a stack of species distribution maps that is then subjected to classification, ordination or aggregation; and (iii) 'assemble and predict together', in which all species are modelled simultaneously, within a single integrated modelling process. These strategies each have particular strengths and weaknesses, depending on the intended purpose of modelling and the type, quality and quantity of data involved. 4. Synthesis and applications. The potential benefits of modelling large multispecies data sets using community-level, as opposed to species-level, approaches include faster processing, increased power to detect shared patterns of environmental response across rarely recorded species, and enhanced capacity to synthesize complex data into a form more readily interpretable by scientists and decision-makers. Community-level modelling therefore deserves to be considered more often, and more widely, as a potential alternative or supplement to modelling individual species.
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Background: Low to moderate alcohol consumption has been associated with lower coronary heart disease (CHD) risk, an effect mainly mediated by an increase in HDL-cholesterol levels. However, data on the CHD risk associated with high alcohol consumption are conflicting. Methods: In a population-based study of 5,769 men and women, aged 35-75 years, without cardiovascular disease in Switzerland, last week alcohol consumption was categorized into 0, 1-6, 7-13, 14-20, 21-27, 28-34, 035 drinks/week and into nondrinkers (0 drink/week), moderate (1-13), high (14-34) and very high drinkers (035). Blood pressure, lipids and high sensitivity C-reactive protein (hs-CRP) were measured, and the 10-year CHD risk was calculated according to the Framingham risk score. Results: 73% (n = 4,214) of the participants consumed alcohol; 16% (n = 909) were considered as high drinkers and 2% (n = 119) as very high drinkers. In multivariate analysis, increasing alcohol consumption was associated with higher HDL-cholesterol (from 1.57 ± 0.01 [adjusted mean ± SE] in nondrinkers to 1.88 ± 0.03 mmol/L in very high drinkers); triglycerides (1.17 ± 1.01 to 1.32 ± 1.05 mmol/L), and systolic and diastolic blood pressure rose significantly (127.4 ± 0.4 to 132.2 ± 1.4 and 78.7 ± 0.3 to 81.7 ± 0.9 mm Hg, respectively, all p for trend <0.001). Predicted 10-year CHD risk increased from 4.31 ± 0.10 to 4.90 ± 0.37 (p = 0.03) with increasing alcohol use, with a J-shaped relationship. Conclusion: As measured by the 10-year CHD risk, the protective effect of alcohol consumption disappears in very high drinkers, namely because the beneficial increase in HDL-cholesterol may be blunt by a rise in blood pressure levels.
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Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery.
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La reconversion des friches industrielles des secteurs de gare est prometteuse dans l'optique d'un développement urbain dense alternatif à l'étalement. Elles constituent en effet une réserve foncière centrale et bien desservie par les transports publics. La densification de ces terrains stratégiques ne pourra cependant freiner l'étalement urbain qu'à condition d'offrir un cadre de vie attractif pour l'habitat. Notre hypothèse est que l'engagement des pouvoirs publics est déterminant pour assurer cette densification qualifiée. Brown fields regeneration in railway station areas is particularly promising in the perspective of a compact urban development alternative to sprawl. They indeed constitute a central land stock which is well connected to public transportation networks. However, the densification of these strategic lands will make it possible to moderate urban sprawl only by providing an attractive environment for residential activities. Our hypothesis is that public authorities involvement is decisive to ensure such a qualified densification. Die Umnutzung von Industriebrachen in Bahnhofsarealen scheint viel versprechend im Hinblick auf eine Stadtentwicklung nach innen als Alternative zur Ausbreitung. Zentralgelegen, stellen diese ungenutzten Flächen eine strategische Bodenreserve dar, welche gut an das öffentliche Verkehrsmittelnetz angeschlossen ist. Ihre Verdichtung kann jedoch die Stadtausbreitung nur eindämmen unter der Bedingung, einen attraktiven Lebens- und Wohnraum zu bieten. Unsere Hypothese lautet, dass das Ausmass des Engagements der öffentlichen Hand bestimmend ist um diese qualitative Verdichtung sicherzustellen.
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This paper analyzes the delegation of contracting capacity in a moral hazard environment with sequential production in a project which involves a principal and two agents. The agent in charge of the nal production can obtain soft information about the other agent's effort choice by investing in monitoring. I investigate the circumstances under which it is optimal for the principal to use a centralized organization in which she designs the contracts with both agents or to use a decentralized organization in which she contracts only one agent, and delegates the power to contract the other agent. It is shown that in this setting a decentralized organization can be superior to a centralized organization. This is because the principal is better off under monitoring and the incentives for an agent to invest in monitoring can be higher in a decentralized organization. The circumstances under which this is true are related to the monitoring costs and the importance of each agent for production. The results explain the recent application of the design-build method in public procurement. Journal of Economic Literature Classi cation Numbers: D23, D82, L14, L22. Keywords: Decentralization of Contracting, Monitoring, Moral Hazard.
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Showing smokers their own atherosclerotic plaques might increase motivation for smoking cessation, since they underestimate their own risk for smoking-related diseases. To assess the feasibility and optimal processes of studying the impact of carotid atherosclerotic plaque screening in smokers, we enrolled 30 daily cigarette smokers, aged 40-70 years, in an observational pre-post pilot study. All smokers underwent smoking cessation counseling, nicotine replacement therapy, a carotid ultrasound, an educational tutorial on atherosclerosis, baseline and 2-month motivation to change assessment, and assessment of smoking cessation at 2 months. Participants had a mean smoking duration of 34 years (SD = 7). Carotid plaques were present in 22 smokers (73%). Between baseline and 2 months after plaque screening, motivation for smoking cessation increased from 7.4 to 8.4 out of 10 (p = .02), particularly in those with plaques (7.2 to 8.7, p = .008). At 2 months, the smoking quit rate was 63%, with a quit rate of 73% in those with plaques vs. 38% in those without plaques (p = .10). Perceived stress, anxiety, and depression did not increase after screening. 96% of respondents answered correctly at least 80% of questions regarding atherosclerosis knowledge at baseline and after 2 months. In conclusion, studying the process of screening for carotid plaques for the purpose of increasing motivation for smoking cessation, in addition to counseling and drug therapy for smoking cessation in long-term smokers, appears feasible. The impact of carotid plaque screening on smoking cessation should be examined in larger randomized controlled trials with sufficient power to assess the impact on long-term smoking cessation rates.
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Purpose: Dysmenorrhea is the leading cause of recurrent short-term school absenteeism among adolescent girls. Yet, studies of menstrual symptoms in the light of adolescent psychological background seldom appear in the recent literature. This study aims to determine whether adolescent girls with severe dysmenorrhea (SD) have different body perception on top of poorer psychological health. Methods: We analyzed data from the Swiss Multicentre Adolescent Survey on Health (SMASH 2002) among a nationally representative sample of adolescents (n = 7548; 3340 females) aged 16 to 20 years attending post-mandatory education. Dysmenorrhea was defined as presence of abdominal or back pain during menstruation on the last 12 months. The severity of dysmenorrhea was defined according to the impact on daily activity and was assessed by 3 questions on the way menstruations interfere with daily life: 1) "You feel well and have normal activities", 2)"you must stay at home" and 3) "you feel restricted in your school or professional activities". Studied variables were: depressive symptoms, suicidal attempt, sexual abuse, health perception in general, body satisfaction, desire to modify body shape, and disordered eating behavior (DEB) with restrictive or bulimic tendency. Controlling variables included socio-economic status (SES) as measured by both parent's level of education, gynecological age (age-age at menarche), academic track (student/apprentice) and age. Results: 12.4% (95% CI: 11.0-14) declared severe dysmenorrhea, 74.2% (95% CI: 71.8-76.5) mild to moderate dysmenorrhea and 13,4% (95% CI: 11.5-15.5) had no dysmenorrhea. Compared to their peers, controlling for confounding variables, subjects with SD were more numerous to report depressive symptoms (AOR: 1.73; 95% CI: 1.39-2.15), to feel in poor health (AOR: 1.44; 95% CI: 1.14-1.81). Moreover, the proportion of those reporting dissatisfaction with their body appearance was higher (AOR: 1.48; 95% CI: 1.00-2.18). Conclusion: Patients with SD not only show a different profile than their peers in terms of their mental health and health perception, but also a distinct relation to their body. Therefore clinicians should pay particular attention to patients with SD and offer them a global evaluation keeping in mind what can be associated with SD.
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Prior genome-wide association studies (GWAS) of major depressive disorder (MDD) have met with limited success. We sought to increase statistical power to detect disease loci by conducting a GWAS mega-analysis for MDD. In the MDD discovery phase, we analyzed more than 1.2 million autosomal and X chromosome single-nucleotide polymorphisms (SNPs) in 18 759 independent and unrelated subjects of recent European ancestry (9240 MDD cases and 9519 controls). In the MDD replication phase, we evaluated 554 SNPs in independent samples (6783 MDD cases and 50 695 controls). We also conducted a cross-disorder meta-analysis using 819 autosomal SNPs with P<0.0001 for either MDD or the Psychiatric GWAS Consortium bipolar disorder (BIP) mega-analysis (9238 MDD cases/8039 controls and 6998 BIP cases/7775 controls). No SNPs achieved genome-wide significance in the MDD discovery phase, the MDD replication phase or in pre-planned secondary analyses (by sex, recurrent MDD, recurrent early-onset MDD, age of onset, pre-pubertal onset MDD or typical-like MDD from a latent class analyses of the MDD criteria). In the MDD-bipolar cross-disorder analysis, 15 SNPs exceeded genome-wide significance (P<5 × 10(-8)), and all were in a 248 kb interval of high LD on 3p21.1 (chr3:52 425 083-53 822 102, minimum P=5.9 × 10(-9) at rs2535629). Although this is the largest genome-wide analysis of MDD yet conducted, its high prevalence means that the sample is still underpowered to detect genetic effects typical for complex traits. Therefore, we were unable to identify robust and replicable findings. We discuss what this means for genetic research for MDD. The 3p21.1 MDD-BIP finding should be interpreted with caution as the most significant SNP did not replicate in MDD samples, and genotyping in independent samples will be needed to resolve its status.
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OBJECTIVE: To investigate the safety and efficacy of 50-Hz repetitive transcranial magnetic stimulation (rTMS) in the treatment of motor symptoms in Parkinson disease (PD). BACKGROUND: Progression of PD is characterized by the emergence of motor deficits that gradually respond less to dopaminergic therapy. rTMS has shown promising results in improving gait, a major cause of disability, and may provide a therapeutic alternative. Prior controlled studies suggest that an increase in stimulation frequency might enhance therapeutic efficacy. METHODS: In this randomized, double blind, sham-controlled study, the authors investigated the safety and efficacy of 50-Hz rTMS of the motor cortices in 8 sessions over 2 weeks. Assessment of safety and clinical efficacy over a 1-month period included timed tests of gait and bradykinesia, Unified Parkinson's Disease Rating Scale (UPDRS), and additional clinical, neurophysiological, and neuropsychological parameters. In addition, the safety of 50-Hz rTMS was tested with electromyography-electroencephalogram (EMG-EEG) monitoring during and after stimulation. RESULTS: The authors investigated 26 patients with mild to moderate PD: 13 received 50-Hz rTMS and 13 sham stimulation. The 50-Hz rTMS did not improve gait, bradykinesia, and global and motor UPDRS, but there appeared a short-lived "on"-state improvement in activities of daily living (UPDRS II). The 50-Hz rTMS lengthened the cortical silent period, but other neurophysiological and neuropsychological measures remained unchanged. EMG/EEG recorded no pathological increase of cortical excitability or epileptic activity. There were no adverse effects. CONCLUSION: It appears that 50-Hz rTMS of the motor cortices is safe, but it fails to improve motor performance and functional status in PD. Prolonged stimulation or other techniques with rTMS might be more efficacious but need to be established in future research.