Quand la pornographie fait violence... réflexions sur les méfaits de la pornographie sur la construction de la sexualité adolescente

Dans notre pratique auprès des adolescents engagés dans des agirs sexuels violents, la consommation de pornographie est fréquemment convoquée dans le parcours de ces sujets à la découverte de la sexualité. Si bien sûr, tous les adolescents qui visionnent ces images ne commettent pas de tels actes, ce constat préoccupant nous invite à nous interroger sur les effets ou plutôt les méfaits de la pornographie sur l'investissement du corps sexué et sur la construction de la sexualité. Outre une réflexion sur l'impact de l'image dans son caractère obscène et à la suite des travaux de G. Bonnet (2003, Le Défi à la pudeur. Quand la pornographie devient l'initiation sexuelle des jeunes), nous montrerons en quoi la pornographie constitue une forme de violence, parfois jusqu'au traumatisme. Ce danger auquel les adolescents sont (sur)exposés, notamment par le biais d'Internet, pourrait en effet favoriser un clivage (que nous retrouvons systématiquement dans la problématique des violences sexuelles) entre corps érotique et corps sexué. La consommation de pornographie s'apparenterait davantage à l'incorporation de la sexualité génitale marquant ainsi l'échec de l'introjection de la génitalité au moment de l'adolescence. Ne devient-elle pas alors un ersatz de la pulsion de mort ? en tant qu'elle isole le sujet dans une activité auto-pseudo-érotique, retirant à la sexualité sa fonction de lien et par là même ouvrant le champ au déchaînement de toutes formes de violence.

Validation of the potentially avoidable hospital readmission rate as a routine indicator of the quality of hospital care

BACKGROUND: The hospital readmission rate has been proposed as an important outcome indicator computable from routine statistics. However, most commonly used measures raise conceptual issues. OBJECTIVES: We sought to evaluate the usefulness of the computerized algorithm for identifying avoidable readmissions on the basis of minimum bias, criterion validity, and measurement precision. RESEARCH DESIGN AND SUBJECTS: A total of 131,809 hospitalizations of patients discharged alive from 49 hospitals were used to compare the predictive performance of risk adjustment methods. A subset of a random sample of 570 medical records of discharge/readmission pairs in 12 hospitals were reviewed to estimate the predictive value of the screening of potentially avoidable readmissions. MEASURES: Potentially avoidable readmissions, defined as readmissions related to a condition of the previous hospitalization and not expected as part of a program of care and occurring within 30 days after the previous discharge, were identified by a computerized algorithm. Unavoidable readmissions were considered as censored events. RESULTS: A total of 5.2% of hospitalizations were followed by a potentially avoidable readmission, 17% of them in a different hospital. The predictive value of the screen was 78%; 27% of screened readmissions were judged clearly avoidable. The correlation between the hospital rate of clearly avoidable readmission and all readmissions rate, potentially avoidable readmissions rate or the ratio of observed to expected readmissions were respectively 0.42, 0.56 and 0.66. Adjustment models using clinical information performed better. CONCLUSION: Adjusted rates of potentially avoidable readmissions are scientifically sound enough to warrant their inclusion in hospital quality surveillance.

On the number of independent cultural traits carried by individuals and populations.

In species subject to individual and social learning, each individual is likely to express a certain number of different cultural traits acquired during its lifetime. If the process of trait innovation and transmission reaches a steady state in the population, the number of different cultural traits carried by an individual converges to some stationary distribution. We call this the trait-number distribution. In this paper, we derive the trait-number distributions for both individuals and populations when cultural traits are independent of each other. Our results suggest that as the number of cultural traits becomes large, the trait-number distributions approach Poisson distributions so that their means characterize cultural diversity in the population. We then analyse how the mean trait number varies at both the individual and population levels as a function of various demographic features, such as population size and subdivision, and social learning rules, such as conformism and anti-conformism. Diversity at the individual and population levels, as well as at the level of cultural homogeneity within groups, depends critically on the details of population demography and the individual and social learning rules.

Virtual Environment: assistance in nursing care for the deaf based on the protocol of Primary Care

Objective: Presenting a Virtual Environment (VE) based on the Protocol of Treatment of Hypertension and Diabetes Mellitus type 2, used in Primary Care for evaluation of dietary habits in nursing consultations. Method: An experimental study applied by two nurses and a nurse manager, in a sample of 30 deaf patients aged between 30 and 60 years. The environment was built in Visual Basic NET and offered eight screens about feeding containing food pictures, videos in Libras (Brazilian sign language) and audio. The analysis of the VE was done through questionnaires applied to patients and professionals by the Poisson statistical test. Results: The VE shows the possible diagnostics in red, yellow, green and blue colors, depending on the degree of patients’ need. Conclusion: The environment obtained excellent acceptance by patients and nurses, allowing great interaction between them, even without an interpreter. The time in consultation was reduced to 15 minutes, with the preservation of patient privacy.

Health indicators associated with poor sleep quality among university students

Objective To associate the sleep quality of Brazilian undergraduate students with health indicators. Method A cross-sectional study was developed with a random sample of 662 undergraduate students from Fortaleza, Brazil. The demographic data, Pittsburgh Sleep Quality Index and health data indicators (smoking, alcoholism, sedentary lifestyle, nutritional condition and serum cholesterol) were collected through a self-administered questionnaire. Blood was collected at a clinical laboratory. In order to estimate the size of the associations, a Poisson Regression was used. Results For students who are daily smokers, the occurrence of poor sleep was higher than in non-smokers (p<0.001). Prevalence rate values were nevertheless close to 1. Conclusion The likelihood of poor sleep is almost the same in smokers and in alcoholics.


The Effect of Four-Lane to Three-Lane Conversion on the Number of Crashes and Crash Rates in Iowa Roads, June 2005

We analyze crash data collected by the Iowa Department of Transportation using Bayesian methods. The data set includes monthly crash numbers, estimated monthly traffic volumes, site length and other information collected at 30 paired sites in Iowa over more than 20 years during which an intervention experiment was set up. The intervention consisted in transforming 15 undivided road segments from four-lane to three lanes, while an additional 15 segments, thought to be comparable in terms of traffic safety-related characteristics were not converted. The main objective of this work is to find out whether the intervention reduces the number of crashes and the crash rates at the treated sites. We fitted a hierarchical Poisson regression model with a change-point to the number of monthly crashes per mile at each of the sites. Explanatory variables in the model included estimated monthly traffic volume, time, an indicator for intervention reflecting whether the site was a “treatment” or a “control” site, and various interactions. We accounted for seasonal effects in the number of crashes at a site by including smooth trigonometric functions with three different periods to reflect the four seasons of the year. A change-point at the month and year in which the intervention was completed for treated sites was also included. The number of crashes at a site can be thought to follow a Poisson distribution. To estimate the association between crashes and the explanatory variables, we used a log link function and added a random effect to account for overdispersion and for autocorrelation among observations obtained at the same site. We used proper but non-informative priors for all parameters in the model, and carried out all calculations using Markov chain Monte Carlo methods implemented in WinBUGS. We evaluated the effect of the four to three-lane conversion by comparing the expected number of crashes per year per mile during the years preceding the conversion and following the conversion for treatment and control sites. We estimated this difference using the observed traffic volumes at each site and also on a per 100,000,000 vehicles. We also conducted a prospective analysis to forecast the expected number of crashes per mile at each site in the study one year, three years and five years following the four to three-lane conversion. Posterior predictive distributions of the number of crashes, the crash rate and the percent reduction in crashes per mile were obtained for each site for the months of January and June one, three and five years after completion of the intervention. The model appears to fit the data well. We found that in most sites, the intervention was effective and reduced the number of crashes. Overall, and for the observed traffic volumes, the reduction in the expected number of crashes per year and mile at converted sites was 32.3% (31.4% to 33.5% with 95% probability) while at the control sites, the reduction was estimated to be 7.1% (5.7% to 8.2% with 95% probability). When the reduction in the expected number of crashes per year, mile and 100,000,000 AADT was computed, the estimates were 44.3% (43.9% to 44.6%) and 25.5% (24.6% to 26.0%) for converted and control sites, respectively. In both cases, the difference in the percent reduction in the expected number of crashes during the years following the conversion was significantly larger at converted sites than at control sites, even though the number of crashes appears to decline over time at all sites. Results indicate that the reduction in the expected number of sites per mile has a steeper negative slope at converted than at control sites. Consistent with this, the forecasted reduction in the number of crashes per year and mile during the years after completion of the conversion at converted sites is more pronounced than at control sites. Seasonal effects on the number of crashes have been well-documented. In this dataset, we found that, as expected, the expected number of monthly crashes per mile tends to be higher during winter months than during the rest of the year. Perhaps more interestingly, we found that there is an interaction between the four to three-lane conversion and season; the reduction in the number of crashes appears to be more pronounced during months, when the weather is nice than during other times of the year, even though a reduction was estimated for the entire year. Thus, it appears that the four to three-lane conversion, while effective year-round, is particularly effective in reducing the expected number of crashes in nice weather.

Suicide in HIV-infected individuals and the general population in Switzerland, 1988-2008.

OBJECTIVE: High rates of suicide have been described in HIV-infected patients, but it is unclear to what extent the introduction of highly active antiretroviral therapy (HAART) has affected suicide rates. The authors examined time trends and predictors of suicide in the pre-HAART (1988-1995) and HAART (1996-2008) eras in HIV-infected patients and the general population in Switzerland. METHOD: The authors analyzed data from the Swiss HIV Cohort Study and the Swiss National Cohort, a longitudinal study of mortality in the Swiss general population. The authors calculated standardized mortality ratios comparing HIV-infected patients with the general population and used Poisson regression to identify risk factors for suicide. RESULTS: From 1988 to 2008, 15,275 patients were followed in the Swiss HIV Cohort Study for a median duration of 4.7 years. Of these, 150 died by suicide (rate 158.4 per 100,000 person-years). In men, standardized mortality ratios declined from 13.7 (95% CI=11.0-17.0) in the pre-HAART era to 3.5 (95% CI=2.5-4.8) in the late HAART era. In women, ratios declined from 11.6 (95% CI=6.4-20.9) to 5.7 (95% CI=3.2-10.3). In both periods, suicide rates tended to be higher in older patients, in men, in injection drug users, and in patients with advanced clinical stage of HIV illness. An increase in CD4 cell counts was associated with a reduced risk of suicide. CONCLUSIONS: Suicide rates decreased significantly with the introduction of HAART, but they remain above the rate observed in the general population, and risk factors for suicide remain similar. HIV-infected patients remain an important target group for suicide prevention.

Biomechanical characterization and in vitro mechanical injury of elderly human femoral head cartilage: comparison to adult bovine humeral head cartilage.

OBJECTIVES: In vitro mechanical injury of articular cartilage is useful to identify events associated with development of post-traumatic osteoarthritis (OA). To date, many in vitro injury models have used animal cartilage despite the greater clinical relevance of human cartilage. We aimed to characterize a new in vitro injury model using elderly human femoral head cartilage and compare its behavior to that of an existing model with adult bovine humeral head cartilage. DESIGN: Mechanical properties of human and bovine cartilage disks were characterized by elastic modulus and hydraulic permeability in radially confined axial compression, and by Young's modulus, Poisson's ratio, and direction-dependent radial strain in unconfined compression. Biochemical composition was assessed in terms of tissue water, solid, and glycosaminoglycan (GAG) contents. Responses to mechanical injury were assessed by observation of macroscopic superficial tissue cracks and histological measurements of cell viability following single injurious ramp loads at 7 or 70%/s strain rate to 3 or 14 MPa peak stress. RESULTS: Confined compression moduli and Young's moduli were greater in elderly human femoral cartilage vs adult bovine humeral cartilage whereas hydraulic permeability was less. Radial deformations of axially compressed explant disks were more anisotropic (direction-dependent) for the human cartilage. In both cartilage sources, tissue cracking and associated cell death during injurious loading was common for 14 MPa peak stress at both strain rates. CONCLUSION: Despite differences in mechanical properties, acute damage induced by injurious loading was similar in both elderly human femoral cartilage and adult bovine humeral cartilage, supporting the clinical relevance of animal-based cartilage injury models. However, inherent structural differences such as cell density may influence subsequent cell-mediated responses to injurious loading and affect the development of OA.

Différences régionales de l'incidence des fractures de la hanche dues à l'ostéoporose chez les femmes âgées : influence de la condition physique et de la nutrition

Résumé L'ostéoporose est une maladie systémique du squelette caractérisée par une fragilité osseuse augmentée avec pour conséquence une augmentation de la susceptibilité aux fractures. C'est actuellement un important problème de santé publique avec des conséquences majeures pour les systèmes de soins tant d'un point de vue médical que financier. Les projections mondiales prévoient une augmentation significative du nombre de fractures de la hanche d'ici 2050. Cette étude vise à analyser l'influence des apports nutritionnels par rapport à celle de la condition physique sur le risque de fracture ostéoporotique en reprenant les données évaluant la consommation de produits laitiers au sein du collectif de l'étude SEMOF («Evaluation suisse de méthodes de mesure du risque de fracture ostéoporotique»). Nous avons d'abord montré que les apports moyens en calcium des 7788 femmes âgées de 70 ans et plus ayant participé à l'étude sont inférieurs aux recommandations suisses et internationales. Des trois régions étudiées, la Suisse romande est celle où les apports quotidiens moyens en calcium et en protéines provenant des produits laitiers sont les plus faibles et où l'incidence des fractures de la hanche secondaires à l'ostéoporose est la plus élevée. Les apports en calcium et en protéines sont également plus élevés à la campagne par rapport à la ville alors que l'incidence des fractures de la hanche n'est pas significativement différente entre ville et campagne. De plus, nous avons montré que les apports quotidiens moyens en calcium et en protéines provenant des produits laitiers ne diffèrent pas significativement entre les femmes avec ou sans fracture de la hanche pendant le suivi. En revanche, la condition physique des femmes qui ont présenté une fracture de la hanche est significativement moins bonne. Sur la base de données anamnestiques concernant les facteurs de risque de chute et la mobilité, nous avons développé un score permettant d'identifier les femmes les plus à risque de chute. La condition physique de ces femmes, attestée par le test de la chaise et la mesure de la force de préhension est la moins bonne. Toutefois, leurs apports quotidiens moyens en calcium et en protéines provenant des produits laitiers ne diffèrent pas significativement par rapport aux femmes à faible risque de chute. En conclusion, le risque de fracture de la hanche liée à l'ostéoporose est plus élevé chez les femmes de plus de 70 ans vivant en Suisse romande que dans les deux autres régions linguistiques. Il est déterminé avant tout par le risque de chute et par la condition physique. Les apports en calcium et en protéines provenant des produits laitiers, tels que nous les avons évalués ne semblent pas déterminants.

Breast cancer incidence in younger swiss women

Background Breast cancer in younger women has received increased attention in recent years. Although breast cancer is uncommon in young women, it is the most frequent cancer and the leading cause of cancer death for younger women in developed countries. For Switzerland, the United States and several European countries, declines in breast cancer incidence have been reported since around the year 2000, after decades of increase, among women aged 50 and older. On the other hand an increase in the incidence of breast cancer in younger women has been reported in recent years. Therefore, this study aims to evaluate time trends in breast cancer incidence in younger women in Switzerland. Methods Data on invasive breast cancer cases were obtained from the Swiss Cancer Registries of Basel, Fribourg, Geneva, Graubunden/Glarus, Jura, Neuchatel, St. Gallen-Appenzell, Ticino, Valais, Vaud and Zurich, covering the time period 1996 to 2009. Mid-year population estimates for the respective time period were supplied by the Swiss Federal Statistical Office. For females aged 20-49 years, annual age-standardized incidence rates (ASIRs) (European standard) per 100,000 person-years and corresponding 95%-confidence intervals (95% CI) were calculated. For females aged 20-39 and 40-49 years, ASIRs and incidence rate ratios (IRRs) were calculated by grouped time periods, consisting of 3-5 incidence years. IRRs and corresponding 95% CI were calculated using Poisson regression adjusting for age (reference period 1996-2000). Results ASIRs in females aged 20-49 increased gradually since 1996, being 57.36 per 100,000 person-years in 1996 (95% CI 52.54-62.51) and rising to 68.34 (95% CI 63.40-73.57) per 100,000 person-years in 2009. Comparing the time-period 2007-2009 and the reference period 1996-2000, IRRs show values of 1.17 (95% CI 1.04-1.31) for the age-group 20-39 years and 1.04 (95% CI 0.97-1.10) for the age-group 40-49 years. Conclusions Our findings confirm a slight increase in the incidence of invasive breast cancer in younger women in Switzerland during the period 1996-2009. An increase in breast cancer incidence in younger patients is an important public health problem. It warrants further investigations to identify specific risk factors of this population and to better understand the biology of this particular breast cancer.

Distribuição espacial de Aphis gossypii (Glover) (Hemiptera, Aphididae) e Bemisia tabaci (Gennadius) biótipo B (Hemiptera, Aleyrodidae) em algodoeiro Bt e não-Bt

Distribuição espacial de Aphis gossypii (Glover) (Hemiptera, Aphididae) e Bemisia tabaci (Gennadius) biótipo B (Hemiptera, Aleyrodidae) em algodoeiro Bt e não-Bt. O estudo da distribuição espacial de adultos de Bemisia tabaci e de Aphis gossypii nas culturas do algodoeiro Bt e não-Bt é fundamental para a otimização de técnicas de amostragens, além de revelar diferenças de comportamento de espécies não-alvo dessa tecnologia Bt entre as duas cultivares. Nesse sentido, o experimento buscou investigar o padrão da distribuição espacial dessas espécies de insetos no algodoeiro convencional não-Bt e no cultivar Bt. As avaliações ocorreram em dois campos de 5.000 m² cada, nos quais se realizou 14 avaliações com contagem de adultos da mosca-branca e colônias de pulgões. Foram calculados os índices de agregação (razão variância/média, índice de Morisita e Expoente k da Distribuição Binomial Negativa) e realizados os testes ajustes das classes numéricas de indivíduos encontradas e esperadas às distribuições teóricas de freqüência (Poisson, Binomial Negativa e Binomial Positiva). Todas as análises mostraram que, em ambas as cultivares, a distribuição espacial de B. tabaci ajustou-se a distribuição binomial negativa durante todo o período analisado, indicando que a cultivar transgênica não influenciou o padrão de distribuição agregada desse inseto. Já com relação às análises para A. gossypii, os índices de agregação apontaram distribuição agregada nas duas cultivares, mas as distribuições de freqüência permitiram concluir a ocorrência de distribuição agregada apenas no algodoeiro convencional, pois não houve nenhum ajuste para os dados na cultivar Bt. Isso indica que o algodão Bt alterou o padrão normal de dispersão dos pulgões no cultivo.

Location models for airline hubs behaving as M/D/c queues

Models are presented for the optimal location of hubs in airline networks, that take into consideration the congestion effects. Hubs, which are the most congested airports, are modeled as M/D/c queuing systems, that is, Poisson arrivals, deterministic service time, and {\em c} servers. A formula is derived for the probability of a number of customers in the system, which is later used to propose a probabilistic constraint. This constraint limits the probability of {\em b} airplanes in queue, to be lesser than a value $\alpha$. Due to the computational complexity of the formulation. The model is solved using a meta-heuristic based on tabu search. Computational experience is presented.

A finite-population revenue management model and a risk-ratio procedure for the joint estimation of population size and parameters

Many dynamic revenue management models divide the sale period into a finite number of periods T and assume, invoking a fine-enough grid of time, that each period sees at most one booking request. These Poisson-type assumptions restrict the variability of the demand in the model, but researchers and practitioners were willing to overlook this for the benefit of tractability of the models. In this paper, we criticize this model from another angle. Estimating the discrete finite-period model poses problems of indeterminacy and non-robustness: Arbitrarily fixing T leads to arbitrary control values and on the other hand estimating T from data adds an additional layer of indeterminacy. To counter this, we first propose an alternate finite-population model that avoids this problem of fixing T and allows a wider range of demand distributions, while retaining the useful marginal-value properties of the finite-period model. The finite-population model still requires jointly estimating market size and the parameters of the customer purchase model without observing no-purchases. Estimation of market-size when no-purchases are unobservable has rarely been attempted in the marketing or revenue management literature. Indeed, we point out that it is akin to the classical statistical problem of estimating the parameters of a binomial distribution with unknown population size and success probability, and hence likely to be challenging. However, when the purchase probabilities are given by a functional form such as a multinomial-logit model, we propose an estimation heuristic that exploits the specification of the functional form, the variety of the offer sets in a typical RM setting, and qualitative knowledge of arrival rates. Finally we perform simulations to show that the estimator is very promising in obtaining unbiased estimates of population size and the model parameters.

A very rare cancer in Down syndrome: medulloblastoma. Epidemiological data from 13 countries.

Persons with Down syndrome (DS) uniquely have an increased frequency of leukemias but a decreased total frequency of solid tumors. The distribution and frequency of specific types of brain tumors have never been studied in DS. We evaluated the frequency of primary neural cell embryonal tumors and gliomas in a large international data set. The observed number of children with DS having a medulloblastoma, central nervous system primitive neuroectodermal tumor (CNS-PNET) or glial tumor was compared to the expected number. Data were collected from cancer registries or brain tumor registries in 13 countries of Europe, America, Asia and Oceania. The number of DS children with each category of tumor was treated as a Poisson variable with mean equal to 0.000884 times the total number of registrations in that category. Among 8,043 neural cell embryonal tumors (6,882 medulloblastomas and 1,161 CNS-PNETs), only one patient with medulloblastoma had DS, while 7.11 children in total and 6.08 with medulloblastoma were expected to have DS. (p 0.016 and 0.0066 respectively). Among 13,797 children with glioma, 10 had DS, whereas 12.2 were expected. Children with DS appear to be specifically protected against primary neural cell embryonal tumors of the CNS, whereas gliomas occur at the same frequency as in the general population. A similar protection against neuroblastoma, the principal extracranial neural cell embryonal tumor, has been observed in children with DS. Additional genetic material on the supernumerary chromosome 21 may protect against embryonal neural cell tumor development.