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Valuing the benefit of varicella vaccination: comparison of willingness to pay and quality-adjusted life-years
Vaccination is different from most health interventions because it is preventative, it protects against infectious disease (leading to knock-on effects), the diseases it prevents are usually acute and self-limiting, and most vaccines are given to children from whom it is very difficult to elicit preferences. Because of its unique characteristics, vaccination may possess its own specific attributes. In this paper, we estimate the average Willingness to Pay (WTP) for varicella vaccination and the Quality-Adjusted Life-Years (QALY) lost due to chickenpox using Contingent Valuation (CV), Standard Gamble and Health Utility Index Mark II (HUI2). Furthermore, we identify what attributes of vaccination are important to vaccinees and what elicitation technique can capture these components. To do this, we administered computerised interviews to a sample of parents attending primary Health Centres. Using CV we demonstrate that individuals are willing to pay more for vaccination than treatment. Furthermore, we show that prevention of work loss is an important intervention attribute for parents. On the other hand, consistent with economic theory, the elicitation techniques used to estimate QALYs (Standard Gamble and HUI2) did not capture non-health benefits. Finally, results elicited using the CV were correlated with QALYs measured through the HUI2 questionnaire
Microclimats et agriculture à Saint-Fulgence (Québec) : leurs potentiels pour l'horticulture : une analyse géographique
L'étude vise à élaborer un modèle d'aménagement territorial dans lequel les conditions microclimatiques favorables à l'agriculture sont prises en compte. Elle s'inscrit sous l'angle des nouveaux regards à poser sur les ressources. Elle concerne la municipalité de Saint-Fulgence au Québec, particulièrement un corridor de trois kilomètres de largeur longeant la rivière Saguenay. Une aire comprenant 88 hectares en horticulture. Le rapport présente, dans un premier temps, les justifications sociales, économiques, politiques, écologiques et géographiques qui ont été la bougie d'allumage de la recherche. Puis, sont énumérées les différentes méthodes et les outils qui sont mis en oeuvre. L'analyse intégrée à l'aide du système d'information géographique de divers paramètres physiographiques, géologiques et d'utilisation du sol est le coeur de la démarche de recherche. Le portrait de l'activité agricole est effectué par la cartographie des cultures au niveau de parcelles homogènes. L'étude met l'accent sur un type d'activité agricole spécifique qu'est l'horticulture, qui comprend les cultures maraîchères, les fruits, les petits fruits, la vigne, les arbres fruitiers et l'arboriculture; ce sont des choix culturaux pouvant être le signe de la présence de microclimats favorables à ces cultures. Les conditions de terrain dans lesquelles s'effectue la production horticole sont alors dégagées; c'est ce que l'on appelle la caractérisation. Interviennent ainsi les questions d'altitude, de proximité de l'eau, de pente, de rayonnement solaire et de dépôts de surface. Puis, il a été possible de déterminer des modèles cartographiques où il est démontré que les conditions propres aux parcelles où on s'adonne à des cultures dites "raffinées" se retrouvent aussi ailleurs dans la municipalité. Il serait donc possible d'agrandir de neuf fois les superficies actuellement cultivées. Finalement, il est proposé des pistes d'aménagement grâce auxquelles l'extension d'une agriculture plus exigeante en termes climatiques pourrait être réalisée
Un microclimat favorable Ă l'horticulture au Saguenay : les trois soleils de Saint-Fulgence
Le cas qui est présenté ici montre comment, dans une volonté de diversification de la production agricole et de meilleure utilisation des terres, notre équipe a su développer une méthodologie et un outil en matière de microclimat pouvant être utiles aux responsables de l’aménagement du territoire, notamment à l’échelle locale
Assortative mixing as a source of bias in epidemiological studies of sexually transmitted infections: the case of smoking and human papillomavirus
For studies examining risk factors of sexually transmitted infections (STIs), confounding can stem from characteristics of partners of study subjects, and persist after adjustment for the subjects’ individual-level characteristics. Two conditions that can result in confounding by the subjects’ partners are: (C1) partner choice is assortative by the risk factor examined and, (C2) sexual activity is associated with the risk factor. The objective of this paper is to illustrate the potential impact of the assortativity bias in studies examining STI risk factors, using smoking and human papillomavirus (HPV) as an example. We developed an HPV transmission-dynamic mathematical model in which we nested a cross-sectional study assessing the smoking–HPV association. In our base case, we assumed (1) no effect of smoking on HPV, and (2) conditions C1–C2 hold for smoking (based on empirical data). The assortativity bias caused an overestimation of the odds ratio (OR) in the simulated study after perfect adjustment for the subjects’ individual-level characteristics (adjusted OR 1·51 instead of 1·00). The bias was amplified by a lower basic reproductive number (R(0)), greater mixing assortativity and stronger association of smoking with sexual activity. Adjustment for characteristics of partners is needed to mitigate assortativity bias
The role of chemotherapy in the management of olfactory neuroblastoma: A 40-year surveillance, epidemiology, and end results registry study
Background: In this retrospective surveillance, epidemiology, and end results (SEER) registry analysis, we investigated the role of chemotherapy (CT) in the treatment of olfactory neuroblastoma (ON), an exceedingly rare sino-nasal tumor typically treated with surgery and/or radiation therapy (RT).
Methods: We analyzed all patients in the SEER registry diagnosed with a single primary malignancy of ON, a primary tumor site within the nasal cavity or surrounding sinuses, sufficient staging information to derive Kadish staging, and \u3e0 days of survival, ensuring follow-up data. Receipt of CT in the SEER registry was documented as either Yes or No/Unknown.
Results: Six hundred and thirty-six patients were identified. One hundred and ninety-five patients received CT as part of their treatment for ON. Following propensity score matching and inverse probability of treatment weighting, there was inferior overall survival (OS) (HR 1.7, 95% CI: 1.3-2.2, P = .001) and cancer-specific survival (CSS) (HR 1.8, 95% CI: 1.3-2.4, P \u3c .001) for patients who received CT compared to those who were not treated with CT or had unknown CT status. On subgroup analysis, the only patient population that derived benefit from CT were patients who did not receive surgery and were treated with CT and/or RT (HR 0.3, 95% CI: 0.14-0.61, P \u3c .001).
Conclusions: Based on this retrospective SEER registry analysis, the use of CT in the management of ON is associated with decreased OS. Our analysis suggests that patients who are considered nonsurgical candidates may benefit from the addition of CT
Inventaire territorial et analyse cartographique de trois régions québécoises : Bas-Saint-Laurent, Gaspésie-Îles-de-la-Madeleine, Côte-Nord et du Golfe du Saint-Laurent : dans le cadre de l'évaluation environnementale stratégique des hydrocarbures au Québec et du plan d'acquisition global des connaissances chantier société (GSOC-01)
L’objectif de la recherche est de réaliser un inventaire territorial et une analyse cartographique décrivant le territoire, le plus finement possible, à un moment donné de son évolution, en matière d’aménagement et d’usages du sol afin de déterminer des aires de sensibilité du territoire à l’étude concerné par l’exploitation des hydrocarbures et gazière. [...] Ce territoire regroupe 173 municipalités et 8 réserves autochtones pour une superficie totale de 316 223 km2 dont 43 % est constitué par le milieu marin. Un peu plus de 336 000 personnes l’habitent. L`hypothèse de base de cette recherche est que les diverses composantes territoriales (32) et d’usage du sol, formant des aires plus ou moins sensibles selon une méthodologie éprouvée, pourraient être affectées, à différents niveaux, selon leur localisation, à la suite d’activités d’exploration et d’exploitation des hydrocarbures et gazières. [...]
Cette étude n’est qu’une petite partie d’un tout. En effet, elle s’intègrera, avec une soixantaine d’autres, dans deux évaluations environnementales stratégiques (filière des hydrocarbures et Anticosti), initiées par le Gouvernement du Québec en mai 2014, et qui comprennent deux grandes phases:
1) la synthèse des connaissances actuelles
et l’identification des lacunes;
2) l’acquisition de nouvelles connaissances. Elle s’intègre plus particulièrement dans un des cinq chantiers des ÉES, soit celui du chantier société (GSOC-01) qui coordonne trois autres recherches universitaires
Diurnal and developmental differences in gene expression between adult dispersing and flightless morphs of the wing polymorphic cricket, \u3ci\u3eGryllus firmus\u3c/i\u3e: Implications for life-history evolution
The functional basis of life history adaptation is a key topic of research in life history evolution. Studies of wing polymorphism in the cricket Gryllus firmus have played a prominent role in this field. However, prior in-depth investigations of morph specialization have primarily focused on a single hormone, juvenile hormone, and a single aspect of intermediary metabolism, the fatty-acid biosynthetic component of lipid metabolism. Moreover, the role of diurnal variation in life history adaptation in G. firmus has been understudied, as is the case for organisms in general. Here, we identify genes whose expression differs consistently between the morphs independent of time-of-day during early adulthood, as well as genes that exhibit a strong pattern of morph-specific diurnal expression. We find strong, consistent, morph-specific differences in the expression of genes involved in endocrine regulation, carbohydrate and lipid metabolism, and immunity – in particular, in the expression of an insulin-like-peptide precursor gene and genes involved in triglyceride production. We also find that the flight-capable morph exhibited a substantially greater number of genes exhibiting diurnal change in gene expression compared with the flightless morph, correlated with the greater circadian change in the hemolymph juvenile titer in the dispersing morph. In fact, diurnal differences in expression within the dispersing morph at different times of the day were significantly greater in magnitude than differences between dispersing and flightless morphs at the same time-of-day. These results provide important baseline information regarding the potential role of variable gene expression on life history specialization in morphs of G. firmus, and the first information on genetically-variable, diurnal change in gene expression, associated with a key life history polymorphism. These results also suggest the existence of prominent morph-specific circadian differences in gene expression in G. firmus, possibly caused by the morph-specific circadian rhythm in the juvenile hormone titer.
Nine supplemental files attached below
Incomplete Wood-Ljungdahl pathway facilitates one-carbon metabolism in organohalide-respiring Dehalococcoides mccartyi.
The acetyl-CoA "Wood-Ljungdahl" pathway couples the folate-mediated one-carbon (C1) metabolism to either CO2 reduction or acetate oxidation via acetyl-CoA. This pathway is distributed in diverse anaerobes and is used for both energy conservation and assimilation of C1 compounds. Genome annotations for all sequenced strains of Dehalococcoides mccartyi, an important bacterium involved in the bioremediation of chlorinated solvents, reveal homologous genes encoding an incomplete Wood-Ljungdahl pathway. Because this pathway lacks key enzymes for both C1 metabolism and CO2 reduction, its cellular functions remain elusive. Here we used D. mccartyi strain 195 as a model organism to investigate the metabolic function of this pathway and its impacts on the growth of strain 195. Surprisingly, this pathway cleaves acetyl-CoA to donate a methyl group for production of methyl-tetrahydrofolate (CH3-THF) for methionine biosynthesis, representing an unconventional strategy for generating CH3-THF in organisms without methylene-tetrahydrofolate reductase. Carbon monoxide (CO) was found to accumulate as an obligate by-product from the acetyl-CoA cleavage because of the lack of a CO dehydrogenase in strain 195. CO accumulation inhibits the sustainable growth and dechlorination of strain 195 maintained in pure cultures, but can be prevented by CO-metabolizing anaerobes that coexist with D. mccartyi, resulting in an unusual syntrophic association. We also found that this pathway incorporates exogenous formate to support serine biosynthesis. This study of the incomplete Wood-Ljungdahl pathway in D. mccartyi indicates a unique bacterial C1 metabolism that is critical for D. mccartyi growth and interactions in dechlorinating communities and may play a role in other anaerobic communities
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