Multi-year interlaboratory exercises for the analysis of illicit drugs and metabolites in wastewater:development of a quality control system

Thirty-seven laboratories from 25 countries present the development of an inter-laboratory testing scheme for the analysis of seven illicit drug residues in standard solutions, tap- and wastewater. Almost 10 000 concentration values were evaluated: triplicates of up to five samples and 26 laboratories per year. The setup was substantially improved with experiences gained across the six repetitions (e.g. matrix type, sample conditions, spiking levels). From this, (pre-)analytical issues (e.g. pH adjustment, filtration) were revealed for specific analytes which resulted in formulation of best-practice protocols for inter-laboratory setup and analytical procedures. The results illustrate the effectiveness of the inter-laboratory setup to assess laboratory performance in the framework of wastewater-based epidemiology. The exercise proved that measurements of laboratories were of high quality (>80% satisfactory results for six out of seven analytes) and that analytical follow-up is important to assist laboratories in improving robustness of wastewater-based epidemiology results

Les strategies d'alliance dans le domaine des services globaux de telecommunications

Available from INIST (FR), Document Supply Service, under shelf-number : DO 5124 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

The dual impact of early and concurrent life stress on adults' diurnal cortisol patterns: A prospective study

Contains fulltext : 214433.pdf (publisher's version ) (Closed access)Major life stress often produces a flat diurnal cortisol slope, an indicator of potential long-term health problems. Exposure to stress early in childhood or the accumulation of stress across the life span may be responsible for this pattern. However, the relative impact of life stress at different life stages on diurnal cortisol is unknown. Using a longitudinal sample of adults followed from birth, we examined three models of the effect of stress exposure on diurnal cortisol: the cumulative model, the biological-embedding model, and the sensitization model. As its name implies, the cumulative model focuses on cumulative life stress. In contrast, the biological-embedding model implicates early childhood stress, and the sensitization model posits that current life stress interacts with early life stress to produce flat diurnal cortisol slopes. Our analyses are consistent with the sensitization model, as they indicate that the combination of high stress exposure early in life and high current stress predict flat diurnal cortisol slopes. These novel findings advance understanding of diurnal cortisol patterns and point to avenues for intervention.9 p

Life stress and cortisol reactivity: An exploratory analysis of the effects of stress exposure across life on HPA-axis functioning

Item does not contain fulltextStressful experiences affect biological stress systems, such as the hypothalamic–pituitary–adrenal (HPA) axis. Life stress can potentially alter regulation of the HPA axis and has been associated with poorer physical and mental health. Little, however, is known about the relative influence of stressors that are encountered at different developmental periods on acute stress reactions in adulthood. In this study, we explored three models of the influence of stress exposure on cortisol reactivity to a modified version of the Trier Social Stress Test (TSST) by leveraging 37 years of longitudinal data in a high-risk birth cohort (N = 112). The cumulative stress model suggests that accumulated stress across the lifespan leads to dysregulated reactivity, whereas the biological embedding model implicates early childhood as a critical period. The sensitization model assumes that dysregulation should only occur when stress is high in both early childhood and concurrently. All of the models predicted altered reactivity, but do not anticipate its exact form. We found support for both cumulative and biological embedding effects. However, when pitted against each other, early life stress predicted more blunted cortisol responses at age 37 over and above cumulative life stress. Additional analyses revealed that stress exposure in middle childhood also predicted more blunted cortisol reactivity.12 p