Smoking Behavior and Ethnicity in Jujuy, Argentina: Evidence from a Low-Income Youth Sample

Latin America is the world region with the highest rates of youth tobacco use and widest socioeconomic gaps, yet no data are available on smoking among Indigenous people, the largest disadvantaged group in the region. A self-administered survey of 3,131 8th grade youth enrolled in a random sample of 27 urban and rural schools was administered in 2004 in Jujuy, Argentina. Standard questions adapted from global surveys were used. Compared with youth of European background (11.4%; 95% CI 6.7-15.1), Indigenous (23.0%; 95% CI 21.0-25.0), and Mixed ethnicity (23%; 95% CI 18.9-27.1) youth had higher prevalence of current smoking. The odds of current smoking remained significantly elevated for Indigenous (OR 1.9; 95% CI = 1.1-3.3) and Mixed youth (OR 2.0; 95% CI 1.2-3.4) after controlling for confounders. Other risk factors that were associated with current smoking included: having any friends who smoke, repeating a grade in school, depressive symptoms in previous year, drinking any alcohol in the previous week and thrill seeking orientation. These results underscore the importance of social and cultural diversity aspects of the global tobacco epidemic.

Bidder's Choice Cap Rate Auctions: A New Strategy for Selling Real Estate Portfolios

Prehospital Resuscitated Cardiac Arrest Patients: Role for Induced Hypothermia

This article is a support paper for the National Association of EMS Physicians' position paper on induced therapeutic hypothermia in resuscitated cardiac arrest patients. Induced hypothermia is one of the newest treatments aimed at increasing the dismal neurologically intact survival rate for out-of-hospital cardiac arrest patients. Two landmark studies published in 2002 by the New England Journal of Medicine led to the American Heart Association (AHA) Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care IIa recommendation of cooling unconscious adult patients with return of spontaneous circulation after out-of-hospital cardiac arrest due to ventricular fibrillation to 32 degrees C to 34 degrees C for 12 to 24 hours. Despite many limitations of those studies, the AHA also suggests that this therapy may be beneficial for patients with non-ventricular fibrillation arrests. However, the literature is lacking in answers with regard to the best methods to utilize in cooling patients. While avoiding delay in the initiation of cooling seems logical, the literature is also lacking evidence indicating the ideal time at which to implement cooling. Furthermore, it remains unclear as to which patients may benefit from induced hypothermia. Finally, the literature provides no evidence to support mandating induced hypothermia in the prehospital setting. Given limited prehospital resources, sometimes consisting of only two providers, attention first needs to be given to providing the basic care with the utmost skill. Once the basics are being delivered expertly, consideration can be given to the use of prehospital cooling for the resuscitated cardiac arrest patient in the setting of continued cooling in the hospital.

Optimal Management of an Insurer’s Exposure in a Competitive General Insurance Market

The qualitative behavior of the optimal premium strategy is determined for an insurer in a finite and an infinite market using a deterministic general insurance model. The optimization problem leads to a system of forward-backward differential equations obtained from Pontryagin’s Maximum Principle. The focus of the modelling is on how this optimization problem can be simplified by the choice of demand function and the insurer’s objective. Phase diagrams are used to characterize the optimal control. When the demand is linear in the relative premium, the structure of the phase diagram can be determined analytically. Two types of premium strategy are identified for an insurer in an infinite market, and which is optimal depends on the existence of equilibrium points in the phase diagram. In a finite market there are four more types of premium strategy, and optimality depends on the initial exposure of the insurer and the position of a saddle point in the phase diagram. The effect of a nonlinear demand function is examined by perturbing the linear price function. An analytical optimal premium strategy is also found using inverse methods when the price function is nonlinear.

Human Exposure to Selected Animal Neurocarcinogens: A Biomarker-Based Assessment and Implications for Brain Tumor Epidemiology

This review is based on the proceedings from the Second Lebow Conference, held in Chicago in 2007. The conference concentrated on developing a framework for innovative studies in the epidemiology of environmental exposures, focusing specifically on the potential relationship with brain tumors. Researchers with different perspectives, including toxicology, pharmacokinetics, and epidemiological exposure assessment, exchanged information and ideas on the use of biomarkers of exposure in molecular epidemiology studies and summarized the current knowledge on methods and approaches for biomarker-based exposure assessment. This report presents the state of science regarding biomarker-based exposure assessment of the four most common neurocarcinogens: acrylamide, 1,3-butadiene, N-nitroso compounds, and polycyclic aromatic hydrocarbons. Importantly, these chemicals are also carcinogenic in other organs; therefore, this discussion is useful for environmental epidemiologists studying all cancer types.

Passive Atmospheric Diffusion With Gaussian Fragmentation

Why is information displaced from visual working memory during visual search?

Research has shown that performing visual search while maintaining representations in visual working memory displaces up to one object's worth of information from memory. This memory displacement has previously been attributed to a nonspecific disruption of the memory representation by the mere presentation of the visual search array, and the goal of the present study was to determine whether it instead reflects the use of visual working memory in the actual search process. The first hypothesis tested was that working memory displacement occurs because observers preemptively discard about an object's worth of information from visual working memory in anticipation of performing visual search. Second, we tested the hypothesis that on target-absent trials no information is displaced from visual working memory because no target is entered into memory when search is completed. Finally, we tested whether visual working memory displacement is due to the need to select a response to the search array. The findings rule out these alternative explanations. The present study supports the hypothesis that change-detection performance is impaired when a search array appears during the retention interval due to nonspecific disruption or masking.

Genome-wide strategies for discovering genetic influences on cognition and cognitive disorders: Methodological considerations

Genes play a well-documented role in determining normal cognitive function. This paper focuses on reviewing strategies for the identification of common genetic variation in genes that modulate normal and abnormal cognition with a genome-wide association scan (GWAS). GWASs make it possible to survey the entire genome to discover important but unanticipated genetic influences.

Plasma levels of S100A4 in portopulmonary hypertension

We previously showed that a single nucleotide polymorphism in S100A4 was associated with portopulmonary hypertension (PPHTN) in patients with advanced liver disease. We aimed to determine the association between plasma levels of S100A4 and PPHTN. We performed a case-control study of patients with advanced liver disease. Cases with PPHTN had mean pulmonary artery pressure >25 mmHg, pulmonary vascular resistance >240 dynes s cm(-5) and pulmonary capillary wedge pressure </=15 mmHg. Controls with liver disease had right ventricular systolic pressure <40 mmHg and normal right atrial and ventricular morphology by echocardiography. Plasma samples were assayed for S100A4. The study sample included 14 cases with PPHTN and 32 controls with liver disease. There was no difference in mean age between cases and controls (p = 0.52). Seventy-nine percent of cases were female compared with 44% of controls (p = 0.03). There was no difference in S100A4 levels between cases and controls (p = 0.58). Both groups had significantly higher S100A4 levels than healthy volunteers (p <0.05). There was no significant difference in plasma levels of S100A4 between PPHTN patients and controls with liver disease, although liver disease itself was associated with increased S100A4 levels.

Depressive symptoms and human immunodeficiency virus risk behavior among men who have sex with men in Chennai, India

Men who have sex with men (MSM) in India are a hidden population, facing unique environmental stressors and cultural pressures that place them at risk for depression. Depression may affect HIV risk behavior in MSM, and may affect the degree to which MSM may benefit from HIV prevention interventions. Depression in MSM in India, however, has largely been understudied. Two hundred ten MSM in Chennai completed an interviewer-administered behavioral assessment battery, which included the 20-item Center for Epidemiologic Studies Depression Scale (CES-D), demographics, sexual risk and identity, and other psychosocial variables. Over half (55%) of the sample exceeded the cutoff (CES-D >or= 16) to screen in for clinically significant depressive symptoms; this was associated with having had unprotected anal sex (OR = 1.97; 95% CI: 1.01-3.87) and higher number of male partners (OR = 1.04; 95% CI: 1.01-1.07). Statistically significant bivariate predictors of meeting the screen in for depressive symptoms included sexual identity (Kothi > Panthi; OR = 4.90; 95% CI: 2.30-10.54), not being married (OR = 3.40; 95% CI: 1.72-6.81), not having a child (OR = 4.40; 95% CI: 2.07-9.39), family not knowing about one's MSM identity (OR = 2.30; 95% CI: 1.18-4.90), having been paid for sex (OR = 5.10; p 95% CI: 2.87-9.47), and perceiving that one is at risk for acquiring HIV (OR = 1.10; 95% CI: 1.02-1.17; continuous). In a multivariable logistic-regression model, unique predictors of screening in for depressive symptoms included not being married (AOR = 3.10; 95% CI: 1.23-7.65), having been paid for sex (AOR = 3.80; 95% CI: 1.87-7.99) and the perception of increased risk for HIV (AOR = 1.10; 95% CI: 1.03-1.21; continuous); unprotected anal sex in the 3 months prior to study enrollment approached statistical significance (AOR = 2.00; 95% CI: 0.91-4.48). Depression among MSM in Chennai is of concern and should be considered while developing HIV prevention interventions with this population. MSM who are not married, sex workers, and those who perceive they are at risk for acquiring HIV may be of higher risk for symptoms of depression.