922 research outputs found
Persistence of Problematic Sexual Behaviors in Children
The purpose of this study was to identify personal and family predictors and correlates of persistence of problematic sexual behaviors (PSB) in children. Participants were the families of 49 children (ages 4–11 years) referred by Child Protective Services in 4 administrative districts of Quebec. Caregivers completed interviews and questionnaires twice at a 1-year interval. Results showed that 43% of children persisted with PSB. When age was controlled, greater exposure to sexualized behaviors in the family proved both a correlate and a predictor of PSB persistence in children 12 months later.\ud
Externalizing problems and somatic complaints emerged as correlates of PSB as well. Maltreatment subtypes did not predict PSB persistence
How Can You Attract Angel Investors to Your Business?
Today, business angels use a shortcut method to cut down the new business ventures eligible for funding. Entrepreneurs should consider how these decisions are made when they seek financing.York's Knowledge Mobilization Unit provides services and funding for faculty, graduate students, and community organizations seeking to maximize the impact of academic research and expertise on public policy, social programming, and professional practice. It is supported by SSHRC and CIHR grants, and by the Office of the Vice-President Research & Innovation.
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Étude des résonances électroniques et leur section efficace de décroissance dans les états électroniques et vibrationnels des bases de l'ADN par pertes d'énergies d'électrons de faible énergie
Cette thèse est une étude des probabilités d'interactions (sections efficaces) entre des molécules simples d'intérêt biologique et des électrons secondaires formés par le rayonnement ionisant. Les mesures sont faites à l'aide d'un spectromètre d'électrons par pertes d'énergie. La thèse comprend quatre articles qui exposent à divers degrés les trois grandes étapes dans la réalisation de ce projet. L'article I traite d'un appareil que j'ai conçu et réalisé en collaboration pour déposer en couches minces les bases d'ADN et certains nucléotides sur un substrat cryogénique. C'est le seul système connu permettant, dans des conditions de cryogénie et d'hypervide, de sublimer des molécules sans déplacer le substrat et sans contaminer le vide et les appareils environnants. L'article II concerne essentiellement l'élaboration d'un modèle que j'ai développé en collaboration et appliqué sur la pyrimidine (une molécule prototype aux bases de l'ADN) pour mesurer les sections efficaces dans des conditions de collisions simples. Le modèle est ensuite appliqué dans les articles III et IV aux excitations vibrationnelles puis électroniques de la thymine. L'article III traite aussi d'une nouvelle méthode, que j'ai développée, pour mesurer la densité des molécules déposées sur une surface. De plus, nous avons localisé par spectrométrie électronique plusieurs excitations d'états triplets jusqu'alors non identifiés pour chacune des deux molécules. La dépendance en énergie des sections efficaces nous a également permis d'identifier et de localiser en énergie plusieurs mécanismes de diffusion résonante d'électron. L'étude spectroscopique nous a permis de raffiner notre compréhension des structures vibrationnelle et électronique de la pyrimidine et de la thymine. Les sections efficaces sont, quant à elles, très prisées par les théoriciens. Elles vont permettre de modéliser la distribution de l'énergie déposée dans le milieu biologique notamment au niveau du noyau cellulaire et ainsi permettre de développer des stratégies radiothérapeutiques plus efficaces
High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice.
Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions
Lowbush blueberry fruit yield and growth response to inorganic and organic N-fertilization when competing with two common weed species
Inorganic N fertilizers are commonly used in commercial blueberry fields; however, this form of N can favor increased weed species’ growth, which can ultimately reduce the benefits of fertilization. We hypothesized that chipped ramial wood (CRW) compost is an effective alternative organic fertilizer for blueberry plants when weeds are present, as ericaceous shrub species are generally more efficient in utilizing organic N than herbaceous weed species. In this study, we measured the growth, fruit yield, and foliar N response of lowbush blueberry (Vaccinium angustifolium Aiton) to an application of 45 kg N ha-1 in the form of organic (CRW) or inorganic N (ammonium sulfate) in two areas of a commercial field colonized by either poverty oat grass (Danthonia spicata (L.) Beauv.) or sweet fern (Comptonia peregrina (L.) Coult.). We also assessed the impact of the fertilization treatments on litter decomposition rates. Contrary to our hypothesis, we found no significant increase in blueberry fruit yield or growth using CRW. By contrast, inorganic N-fertilization increased fruit yield by 70%. The effect was higher in the area colonized by D. spicata (+83%) than by C. peregrina (+45%). Blueberry fruit yield was on average twice higher in the area of the field having D. spicata than C. peregrina, suggesting a stronger competition with the latter. However, the increase in D. spicata density from 0–1 to >25 plants m-2 reduced fruit production by three-fold and strongly impacted vegetative growth in both fertilized and unfertilized plots. The impact of increased C. peregrina density was comparatively much lower, especially on vegetative growth, which was much higher in the area having C. peregrina. These patterns are likely due to a lower competition for N uptake with C. peregrina as this species can derive N from the atmosphere. Interestingly, the higher fruit yield in the area colonized by D. spicata occurred even in plots where the weeds were nearly absent (density of 0–1 plant m-2), revealing the influence of unidentified variables on blueberry fruit yield. We hypothesized that this difference resulted from over-optimal foliar N concentrations in the area colonized by C. peregrina as suggested by the significantly higher foliar N concentrations and by the negative correlation between foliar N concentrations and fruit yields in this area. The possibility of an influence of C. peregrina on flowering and pollination success, as well as of unidentified local site conditions is discussed. The tested N-fertilization treatments did not affect foliar N concentrations or litter decomposition rates. Overall, our results show that ammonium sulfate is very effective at increasing fruit yields but that both fruit yields and the efficiency of the N-fertilization treatment are decreased by increased D. spicata density, especially above 25 plants m-2. Although CRW did not significantly enhance fruit yields in the short term, this fertilizer may have a long-term beneficial effect
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Associations Between Hearing Performance and Physiological Measures - An Overview and Outlook
The current paper summarises the research investigating associations between physiological data and hearing performance. An overview of state-of-the-art research and literature is given as well as promising directions for associations between physiological data and data regarding hearing loss and hearing performance. The physiological parameters included in this paper are: electrodermal activity, heart rate variability, blood pressure, blood oxygenation and respiratory rate. Furthermore, the environmental and behavioural measurements of physical activity and body mass index, alcohol consumption and smoking have been included. So far, only electrodermal activity and heart rate variability are physiological signals simultaneously associated with hearing loss or hearing performance. Initial findings suggest blood pressure and respiratory rate to be the most promising physiological measures that relate to hearing loss and hearing performance
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