Concordia University

About: Concordia University is a education organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Context (language use) & Control theory. The organization has 13565 authors who have published 31084 publications receiving 783525 citations. The organization is also known as: Sir George Williams University & Loyola College, Montreal.

Stability and Social-Behavioral Consequences of Toddlers' Inhibited Temperament and Parenting Behaviors

Abstract: A prospective longitudinal design was employed to ascertain whether different types of behavioral inhibition (i.e., traditional, peer‐social) were stable from toddler to preschool age, and whether inhibited temperament and/or parenting style would predict children’s subsequent social and behavioral problems. At Time 1, 108 toddlers (54 males, 54 females) and their mothers were observed in the Traditional Inhibition Paradigm and in a toddler‐peer session; then at age 4 years, 88 children were observed with unfamiliar peers, and maternal ratings of psychological functioning were obtained. How mothers and their toddlers interacted was also observed. Results revealed meaningful connections between toddler inhibition, maternal intrusive control and derision, and nonsocial behaviors at age 4. Both forms of toddler inhibition predicted socially reticent behavior during free play at 4 years. If mothers demonstrated relatively high frequencies of intrusive control and/or derisive comments, then the association between their toddlers’ peer inhibition and 4-year social reticence was significant and positive; whereas if mothers were neither intrusive nor derisive, then toddlers’ peer inhibition and 4-year reticence were not significantly associated. Thus, maternal behaviors moderated the relation between toddlers’ peer inhibition and preschoolers’ social reticence.

What aspects of peer relationships are impaired in children with attention-deficit/hyperactivity disorder?

Abstract: Participants included 165 children with attention-deficit/hyperactivity disorder (ADHD; 130 boys, 35 girls) and their 1,298 same-sex classmates (1,026 boys, 272 girls) who served as raters. For each child with ADHD, a child of the same sex was randomly selected from the same classroom to serve as a comparison child, which yielded 165 dyads. Consistent with predictions, contrasted with the comparison children, those with ADHD were lower on social preference, higher on social impact, less well liked, and more often in the rejected social status category; they also had fewer dyadic friends. When liking ratings that children made versus received were examined, children with ADHD had less positive imbalance and greater negative imbalance relative to comparison children. Analyses that considered the types of peers who chose children with ADHD as friends or nonfriends demonstrated that children with ADHD were nominated as nonfriends by children of higher social preference and who were better liked by others.

Worldwide contamination of food-crops with mycotoxins: Validity of the widely cited 'FAO estimate' of 25.

Abstract: Prior to 1985 the Food and Agriculture Organization (FAO) estimated global food crop contamination with mycotoxins to be 25%. The origin of this statement is largely unknown. To assess the rationale for it, the relevant literature was reviewed and data of around 500,000 analyses from the European Food Safety Authority and large global survey for aflatoxins, fumonisins, deoxynivalenol, T-2 and HT-2 toxins, zearalenone and ochratoxin A in cereals and nuts were examined. Using different thresholds, i.e. limit of detection, the lower and upper regulatory limits of European Union (EU) legislation and Codex Alimentarius standards, the mycotoxin occurrence was estimated. Impact of different aspects on uncertainty of the occurrence estimates presented in literature and related to our results are critically discussed. Current mycotoxin occurrence above the EU and Codex limits appears to confirm the FAO 25% estimate, while this figure greatly underestimates the occurrence above the detectable levels (up to 60-80%). The high occurrence is likely explained by a combination of the improved sensitivity of analytical methods and impact of climate change. It is of immense importance that the detectable levels are not overlooked as through diets, humans are exposed to mycotoxin mixtures which can induce combined adverse health effects.

Photoassisted Degradation of Dye Pollutants. 3. Degradation of the Cationic Dye Rhodamine B in Aqueous Anionic Surfactant/TiO2 Dispersions under Visible Light Irradiation: Evidence for the Need of Substrate Adsorption on TiO2 Particles

Abstract: The TiO2 photoassisted degradation of the cationic dye rhodamine B (RhB) has been examined in aqueous dispersions under visible light irradiation at wavelengths longer than 470 nm in the presence and absence of the anionic surfactant sodium dodecylbenzenesulfonate (DBS). RhB degrades slowly via a pH-independent process in TiO2 dispersions containing no DBS. The surfactant DBS adsorbs strongly on the TiO2 particles and significantly accelerates RhB degradation with initial rates reaching maximal values at the critical micelle concentration of DBS (cmc = 1.2 mM). In the presence of DBS, rates decrease with increase in pH, an effect directly attributable to variations in the extent of adsorption of RhB with changes in the surface charge of TiO2 particles. The zeta (ζ)-potentials of TiO2 particles in RhB/DBS/TiO2 dispersions (pH 2.1) show that DBS significantly enhances RhB adsorption and correlates with an enhancement in the rate of photodegradation of RhB. The results confirm the heretofore presumed but val...