Modulated X-ray Emissivity near the Stress Edge in Sgr A*

Sgr A* is thought to be the radiative manifestation of a ~3.6E6 Msun supermassive black hole at the Galactic center. Its mm/sub-mm spectrum and its flare emission at IR and X-ray wavelengths may be produced within the inner ten Schwarzschild radii of a hot, magnetized Keplerian flow. The lightcurve produced in this region may exhibit quasi-periodic variability. We present ray-tracing simulations to determine the general-relativistically modulated X-ray luminosity expected from plasma coupled magnetically to the rest of the disk as it spirals inwards below the innermost stable circular orbit towards the "stress edge" in the case of a Schwarzschild metric. The resulting lightcurve exhibits a modulation similar to that observed during a recent X-ray flare from Sgr A*.Comment: 4 pages, 3 figures, accepted for publication in ApJ

G2/M blockade by paclitaxel induces caveolin-1 expression in A549 lung cancer cells : caveolin-1 as a marker of cytotoxicity.

Caveolins are highly expressed in terminally differentiated cells, but this expression is down-regulated in various cancer cell lines. Exposure to low doses of paclitaxel (taxol) is sufficient to up-regulate caveolin-1, suggesting that a mild cytotoxic stress induces a response implying caveolin and caveolae. Here we show that this up-regulation is sustained even after the cessation of paclitaxel treatment. After exposure to a cytostatic dose of paclitaxel (50 nM), A549 lung cancer cells are blocked in the G2/M cell cycle phase. After removal of paclitaxel, cell death occurs, accompanied with an increase in caveolin expression, suggesting an effect of caveolin in this process. Three days post-paclitaxel treatment, surviving A549 cells were passaged and only a half of them adhered to the culture dish. Adhering cells (still mainly in the G2/M cell cycle phase) were still unable to grow and progressively entered in an apoptotic state. This study suggests that effects of a low dose of paclitaxel were still present even 1 week after drug removal and that caveolin-1 is a good marker of cytotoxicity

Barriers and facilitators to family participation in the care of their hospitalized loved ones

This study’s objective was to better understand family members’ experiences in order to identify how healthcare organizations can facilitate their participation in the care of a hospitalized loved one. Eighteen individuals at the bedside of a hospitalized loved one were interviewed individually. Roles at the bedside and factors that facilitated their participation or represented barriers were examined. A qualitative analysis using a mixed inductive/deductive approach was performed. Reassurance and emotional support, as well as sharing information with the healthcare team emerged as main roles. Quality and timeliness of the information received about the patient’s condition, prognosis and changes in medical condition, as well as information on how to participate in their care, were the factors most frequently evoked as facilitating participation. On the other hand, the need to improve communication channels and access to doctors were highlighted. Most family members having no prior knowledge or exposure to healthcare environments reported feeling overwhelmed in this foreign environment. Among the suggestions on how to improve their experience, having a well-identified contact person who liaises with them and who can instruct them on how to participate in care during hospitalization and back at home was frequently suggested. Furthermore, many mentioned that recognizing the experiential knowledge they have of the patient allows for more holistic care and contributes to improve both patient and family experience. Families need to be adequately recognized and supported and have access to information in a timely manner so that their contribution to their loved one’s care is maximized and the burden associated with this stressful experience alleviated

Up-regulation of caveolin expression by cytotoxic agents in drug-sensitive cancer cells

Caveolin 1 expression is down-regulated in various cancer cell lines. Interestingly, in several drug-resistant cancer cells, a strong induction of caveolin 1 expression has been reported, suggesting a role for caveolin 1 in the acquisition and/or the maintenance of the multidrug-resistance phenotype. Here, we show, in drug-sensitive lung cancer cells (A549, Calu-6 or NCI-H69), that exposure to cytotoxic drugs (taxol, doxorubicin or etoposide) is sufficient to strongly up-regulate caveolin 1 and 2 protein levels. This up-regulation is sustained even 1 week after drug removal. Our results suggest that caveolin up-regulation is an early cellular response to a cytotoxic stress taking place before drug resistance

Impact des coupes forestières sur l'alimentation et la croissance de l'omble de fontaine (Salvelinus fontinalis) dans des lacs du Bouclier boréal canadien

La récolte forestière modifie les écosystèmes terrestres, mais a également un effet indirect sur les écosystèmes aquatiques. Jusqu'à maintenant, beaucoup d'études ont examiné l'impact des coupes forestières sur les écosystèmes lotiques. Toutefois, les effets sur les milieux lacustres et la faune ichtyenne ont été moins étudiés. De ce fait, il est très important de documenter davantage les impacts des coupes forestières afin de mieux comprendre leurs effets sur les espèces piscicoles en lac. Ces connaissances sont nécessaires pour permettre aux compagnies forestières et aux gouvernements d'améliorer la gestion de cette ressource renouvelable, tout en assurant aux pêcheurs sportifs de bénéficier d'une bonne qualité de pêche dans les zones d'exploitation forestière. L'objectif de cette étude était de déterminer les impacts à court terme des coupes forestières sur l'alimentation et la croissance de l'omble de fontaine (Salvelimis fontinalis) dans les lacs oligotrophes du Bouclier boréal canadien. Pour atteindre cet objectif, des ombles ont été capturés au cours de trois années (juillet 2008-2010), dans quatre lacs dont le bassin versant n'avait subi aucune perturbation et dans quatre lacs perturbés par les coupes forestières après la première année. Afin de vérifier l'effet d'une telle perturbation environnementale sur la diète du salmonidé, l'analyse des contenus stomacaux a été effectuée. Ces analyses n'ont pas permis de déceler des changements quant aux assemblages, aux indices de diversités et l'abondance des types de proies dans l'alimentation des individus âgées de 3 et 4 ans + capturés-suite à la récolte forestière. La variabilité entre les lacs est plus importante que celle attribuable aux coupes forestières. Les otolithes ont été utilisés pour mesurer la croissance chez les ombles de fontaine âgés de trois et quatre ans. Les récoltes forestières n'ont provoqué aucune modification des taux de croissance. Finalement, les résultats suggèrent que malgré une augmentation en phosphore total et en carbone organique dissous dans les lacs perturbés par la coupe forestière, aucune différence n'a été détectée dans l'alimentation et la croissance des ombles de fontaine. Cette étude supporte l'hypothèse selon laquelle l'effet des coupes forestières est dilué chez les espèces situées au sommet du réseau trophique comme l'omble de fontaine adulte dans les lacs de la forêt boréale

Naturalness and Focus Points with Non-Universal Gaugino Masses

Relations between the gaugino masses have been shown to alleviate the degree of fine-tuning in the MSSM. In this paper we consider specific models of supersymmetry breaking with gravity mediation and demonstrate that within both GUT and string constructions it is possible to generate these relations in a natural way. We have numerically studied the degree of fine-tuning in these models, including one-loop corrections, and have found regions of parameter space that can satisfy all known collider constraints with fine-tunings less than 20%. We discuss some of the phenomenological features of these models within the regions of reduced fine-tuning.Comment: 31 pages, 21 figures. Version accepted for publication in Nuclear Physics

Evaluating the integration of chronic disease prevention and management services into primary health care

Background The increasing number of patients with chronic diseases represents a challenge for health care systems. The Chronic Care Model suggests a multi-component remodelling of chronic disease services to improve patient outcomes. To meet the complex and ongoing needs of patients, chronic disease prevention and management (CDPM) has been advocated as a key feature of primary care producing better outcomes, greater effectiveness and improved access to services compared to other sectors. The objective of this study is to evaluate the adaptation and implementation of an intervention involving the integration of chronic disease prevention and management (CDPM) services into primary health care. Methods/Design The implementation of the intervention will be evaluated using descriptive qualitative methods to collect data from various stakeholders (decision-makers, primary care professionals, CDPM professionals and patients) before, during and after the implementation. The evaluation of the effects will be based on a combination of experimental designs: a randomized trial using a delayed intervention arm (n = 326), a before-and-after design with repeated measures (n = 163), and a quasi-experimental design using a comparative cohort (n = 326). This evaluation will utilize self-report questionnaires measuring self-efficacy, empowerment, comorbidity, health behaviour, functional health status, quality of life, psychological well-being, patient characteristics and co-interventions. The study will take place in eight primary care practices of the Saguenay region of Quebec (Canada). To be included, patients will have to be referred by their primary care provider and present at least one of the following conditions (or their risk factors): diabetes, cardiovascular diseases, chronic obstructive pulmonary disease, asthma. Patients presenting serious cognitive problems will be excluded. Discussion In the short-term, improved patient self-efficacy and empowerment are expected. In the mid-term, we expect to observe an improvement in health behaviour, functional health status, quality of life and psychological well-being. At the organizational level, the project should lead to coordinated service delivery, improved patient follow-up mechanisms and enhanced interprofessional collaboration. Integration of CDPM services at the point of care in primary care practices is a promising innovation in care delivery that needs to be thoroughly evaluated

Drinking Water and Potential Threats to Human Health in Nunavik: Adaptation Strategies under Climate Change Conditions

In Nunavik, chlorine-treated water is delivered daily, by tank truck, to the houses, where it is stored in tanks. A large part of the Inuit population continues to depend on an untreated water supply, however. This traditional activity poses certain risks in a region with an abundant presence of migratory animals. Nunavik has also experienced significant climate warming since the beginning of the last decade. The main goal of this study, which took place in 2003 and 2004, was to evaluate drinking habits that may place Nunavik residents at an increased risk of gastroenteric diseases in the context of climate change. During the Amundsen cruise in fall 2004, we observed that raw water from the collection sites most frequently visited (brooks, lakes, rivers) was of good quality in most of the villages. Regular monitoring of these sites is necessary, however, and the public should be warned when the sites become contaminated. Of particular concern was the water from the individual storage containers, which was much more contaminated than the water at the collection sites. To develop or improve the climate change adaptation strategies in this area, we propose 1) establishing an appropriate environmental monitoring system, 2) improving wastewater disposal and municipal water systems, 3) involving nursing staff in microbiological testing of the water at community sites, 4) raising public awareness of the risks related to raw water consumption, and 5) gathering strategic health information during the periods of the year when cases of gastroenteric diseases are most frequent, in order to establish whether there is a link between these disorders and water quality.Au Nunavik, de l’eau traitée par chloration est livrée à domicile tous les jours au moyen d’un camion-citerne, après quoi cette eau est stockée dans des réservoirs. Cependant, une grande partie de la population inuite continue de s’approvisionner en eau non traitée. Cette activité traditionnelle pose certains risques dans une région caractérisée par une abondance d’animaux en migration. Aussi, depuis le début de la dernière décennie, le Nunavik a enregistré un réchauffement climatique considérable. Cette étude, qui s’est déroulée de 2003 à 2004, avait pour but principal d’évaluer les habitudes de consommation d’eau qui sont susceptibles de mettre les habitants du Nunavik davantage à risque de subir des maladies gastro-entériques dans le contexte du changement climatique. Dans le cadre de la croisière de l’Amundsen à l’automne 2004, nous avons constaté que l’eau brute des lieux de collecte les plus souvent visités (les ruisseaux, les lacs et les rivières) était de bonne qualité dans la plupart des villages. Cela dit, la surveillance régulière de ces emplacements s’avère nécessaire et le grand public devrait être averti en cas de contamination. L’eau des contenants de stockage individuels représentait une source de préoccupation particulière, car elle était bien plus contaminée que l’eau des lieux de collecte. Afin d’élaborer ou d’améliorer les stratégies d’adaptation au changement climatique dans cette région, nous proposons ce qui suit : 1) établir un système de surveillance environnementale adéquat, 2) améliorer le système d’élimination des eaux usées et le réseau municipal d’alimentation en eau, 3) faire appel au personnel infirmier pour faire les tests microbiologiques de l’eau aux emplacements communautaires, 4) sensibiliser le grand public davantage aux risques liés à la consommation d’eau non traitée, 5) recueillir des renseignements stratégiques sur la santé pendant les périodes de l’année où les maladies gastro-entériques sont plus fréquentes afin de déterminer s’il existe un lien entre ces maladies et la qualité de l’eau

Supporting information for "Bis-michael acceptors as novel probes to study the Keap1/Nrf2/ARE pathway"

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a master regulator that promotes the transcription of cytoprotective genes in response to oxidative/electrophilic stress. Various Michael-type compounds were designed and synthesized, and their potency to activate the Keap1/Nrf2/ARE pathway was evaluated. Compounds bearing two Michael-type acceptors proved to be the most active. Tether length and rigidity between the acceptors was crucial. This study will help to understand how this feature disrupts the interaction between Keap1 and Nrf2

Validation of a French-language version of the health education impact Questionnaire (heiQ) among chronic disease patients seen in primary care : a cross-sectional study

Background The Health Education Impact Questionnaire (heiQ) allows for the evaluation of the effects of education interventions provided to patients with chronic diseases. This study describes the process for the cross-cultural adaptation and validation of the heiQ into French (heiQ-Fv). Methods We undertook a systematic translation process followed by a validation study based on the secondary analysis of cross-sectional data from a longitudinal study. Participants in the validation study were adult patients from primary care clinics in Quebec, Canada, with one or more of the following diseases: diabetes, asthma, chronic obstructive pulmonary disease, cardiovascular disease; or one or more risk factors for these diseases. Main outcomes of the study were the French version of the heiQ-Fv and the validation analyses that included internal consistency, test-retest reliability, confirmatory factor analysis (CFA) and concomitant validity. Results The validation analysis was conducted on results from 332 participants. Cronbach’s alphas (internal consistency) for seven domains of the heiQ-Fv varied from 0.80 to 0.89; one domain scored 0.69. The test-retest analysis (n = 50) yielded intra-class correlation coefficients from 0.66 to 0.86. The CFA of the eight heiQ domains with the hypothesis of no correlation between the domains yielded a model that did not exhibit acceptable fit values. A model with the hypothesis of all domains correlated exhibited acceptable fit values (scaled chi-square = 1210.15, degrees of freedom = 712, p < 0.001; CFI = 0.98; RMSEA = 0.06; SRMR = 0.065). Results show a moderate correlation (concomitant validity) between five domains of the heiQ-Fv and the Self-Efficacy for Managing Chronic Diseases. We also found a moderate to strong correlation between the Emotional Wellbeing domain of the heiQ and the Kessler Psychological Distress Scale (K6) (r = 0.61; 95 % CI: 0.52 –0.69, p < 0.01). Conclusions The heiQ was translated into French using a rigorous translation process; the French-language version showed good psychometric properties. Health professionals and researchers in primary care settings may use the heiQ-FV to evaluate the impact of educational programs on patients with chronic diseases