Sleep and pre-bedtime activities in New Zealand adolescents: differences by ethnicity.

AIM: To describe the screen and nonscreen activities adolescents engage in one hour before bedtime and associations with sleep quantity and quality, including differences by ethnic group. DESIGN: Cross-sectional survey. PARTICIPANTS: 4,192 adolescents aged 13-17 years (52% boys); 71% NZ European, 13% Maori, 8% Asian, 6% Pacific, and 2% other ethnic groups. MEASURES: Participants completed questions about sleep timing, quality (Pittsburgh Sleep Quality Index), and chronotype (Morningness-Eveningness Scale for Children). Seventeen questions captured pre-bedtime activities. RESULTS: Overall, 39% slept less than the recommended hour of sleep (<8 h) and 57% reported poor sleep quality. Asian teenagers reported shorter sleep duration than New Zealand (NZ) Europeans (-45 min [95% CI: -58 to -32]) primarily from later bedtimes (1 hour), with higher odds of long sleep latency, but less disturbed sleep and a more "eveningness" chronotype. Bedtimes were later in Maori and Pacific adolescents (15 and 41 min, respectively) than NZ Europeans. Most screen activities were negatively associated with sleep quantity and quality. For nonscreen activities, snacking and drinking caffeinated beverages and alcohol were significantly associated with shorter sleep (-8, -28, and -20 min, respectively), whereas interacting with family and friends and exercise/sports before bed were associated with longer sleep (P < 0.001). Time with family, exercise, schoolwork, and household chores were all associated with better sleep quality (P < 0.001). Ethnic differences were apparent for several pre-bedtime activities. DISCUSSION: Ethnic differences related to subjective sleep parameters exist in NZ adolescents. Observed variations in sleep patterns and presleep activities suggest that sleep health messages should be tailored for different ethnic groups.

Modelling the exposure to chemicals for risk assessment: a comprehensive library of multimedia and PBPK models for integration, prediction, uncertainty and sensitivity analysis - the MERLIN-Expo tool.

MERLIN-Expo is a library of models that was developed in the frame of the FP7 EU project 4FUN in order to provide an integrated assessment tool for state-of-the-art exposure assessment for environment, biota and humans, allowing the detection of scientific uncertainties at each step of the exposure process. This paper describes the main features of the MERLIN-Expo tool. The main challenges in exposure modelling that MERLIN-Expo has tackled are: (i) the integration of multimedia (MM) models simulating the fate of chemicals in environmental media, and of physiologically based pharmacokinetic (PBPK) models simulating the fate of chemicals in human body. MERLIN-Expo thus allows the determination of internal effective chemical concentrations; (ii) the incorporation of a set of functionalities for uncertainty/sensitivity analysis, from screening to variance-based approaches. The availability of such tools for uncertainty and sensitivity analysis aimed to facilitate the incorporation of such issues in future decision making; (iii) the integration of human and wildlife biota targets with common fate modelling in the environment. MERLIN-Expo is composed of a library of fate models dedicated to non biological receptor media (surface waters, soils, outdoor air), biological media of concern for humans (several cultivated crops, mammals, milk, fish), as well as wildlife biota (primary producers in rivers, invertebrates, fish) and humans. These models can be linked together to create flexible scenarios relevant for both human and wildlife biota exposure. Standardized documentation for each model and training material were prepared to support an accurate use of the tool by end-users. One of the objectives of the 4FUN project was also to increase the confidence in the applicability of the MERLIN-Expo tool through targeted realistic case studies. In particular, we aimed at demonstrating the feasibility of building complex realistic exposure scenarios and the accuracy of the modelling predictions through a comparison with actual measurements.

Influence of surfactants on the sorption of two chloroacetanilide in an Romanian chernozem soil.

Pesticides have been extensively used in modern agriculture. Due to the prevalent use, there have been serious problems generated by pesticides wastes which could eventually endanger water resources and human health. The development of technologies for the decontamination of soils and waters polluted by hydrophobic organic compounds has encouraged research into the use of non-ionic surfactants as potential agents for the enhanced solubilization and removal of contaminants from soils and sediments. Sorption of two chloroacetanilide herbicides, acetochlor and metolachlor was studied on a representative chernozem soil of the Main Agricultural Research Station Ezareni belonging to the "Ion Ionescu de la Brad" University of Agriculture and Veterinary Medicine lasi, Romania, in the presence and absence of surfactants. Three different non-ionic surfactants were selected: Tween-20, Synperonic 91/5 and Silwet L-77, to verify the influence of their presence on herbicide sorption at different concentrations. Our results showed that the sorption of the studied herbicides within the soil-water-non-ionic surfactant system was influenced by the presence of non-ionic surfactants. The n values obtained were lower than 1 for all pesticide-surfactant combinations, which indicates that the amount of acetochor and metolachlor sorbed decreased with an increase in pesticide concentration. The sorption of acetochlor increased in the following order: Acetochlor+Synperonic 91/5 < Acetochlor < Acetochlor+Tween-20 < Acetochlor+Silwet L-77. In the case of metolachlor+Synperonic and metolachlor+Silwet L-77, the Kf values were significantly higher than the Kf value of metolachlor+Tween-20 on soil, where a lower Kf value could be observed with however a higher n value which indicate a higher sorption capacity at higher concentrations.

A 3D active shape model for the evaluation of the alignment of the spine during sleeping.

This paper explains how the shape of the spine can be evaluated from back surface measurements in a recumbent position, by using point distribution models (PDM) and typical shape variability of the spine in a lateral sleeping position. CT-scans of 12 volunteers were taken in this posture on a firm and a soft sleeping system to provide a training set for the PDM. Active shape models (ASM) were used to enhance the accuracy of the spinal reconstruction from measurements by limiting the shape of the spine to characteristic shapes from a biomechanical and/or clinical point of view. A comparison was made between calculated shapes, obtained from surface measurements, and those measured vertebral body centres (from CT-scans). An RMS accuracy of 2.6mm was obtained in 3D, and 1.8mm in frontal view, which was sufficient to compare spinal deformations of a subject on different sleeping systems.

Optimalisation and feasability of bioremediation systems for the processing of spray losses of pesticides.

Contamination of ground and surface water puts pressure on the use of pesticides. Pesticide contamination of water can often be linked to point sources rather than to diffuse sources. Examples of such point sources are areas on farms where pesticides are handled, filled into sprayers and where sprayers are cleaned. To reduce contamination from these point sources, different kinds of bio-remediation systems are in various member states of the EU. Bioremediation is the use of living organisms, primarily micro-organisms, to degrade the environmental contaminants into less toxic forms. In this study, the behaviour of six different pesticides with varying physico-chemical properties on substrates used in a bioremediation system is studied. The adsorption of individual pesticides on the substrates is determined. After determination of the adsorption coefficient Kd, it could be concluded for metalaxyl that coco chips had the highest sorption capacity, followed by straw, compost, willow chopping and a sandy loam soil.

Identification by quantitative chromatin pattern analysis of patients at risk for recurrence of superficial transitional bladder carcinoma.

PURPOSE: Based on the actual clinical outcomes of 132 fully documented patients with superficial transitional cell carcinoma of the bladder, we characterize the risk of recurrence and/or progression by computer assisted image microscopy applied to Feulgen stained nuclei. MATERIALS AND METHODS: Each tumor was characterized by the conventional grading and staging systems as well as by cytometry generated variables describing nuclear DNA content, nuclear morphometry and chromatin patterns. These data were submitted to discriminant analysis to establish a model distinguishing between 2 groups of patients. Group 1 included cases with remission for more than 60 months and group 2 cases presented with recurrence with or without progression within 12 months of transurethral bladder resection. This latter model was then validated by Kaplan-Meyer analysis of the full data set. RESULTS: As evidenced by Kaplan-Meier analysis, the discriminant factor generated by discriminant analysis of cytometry generated variables provided a cutoff value for distinguishing between low and high risks of recurrence (p <0.00001). In contrast, conventional grading and staging systems were not able to make such efficient distinction. CONCLUSIONS: These 2 groups can be used as references with which new cases can be compared to prognosticate disease behavior independently of histopathological grading and/or clinical staging.

Fetal brain sparing is associated with accelerated shortening of visual evoked potential latencies during early infancy.

OBJECTIVE: Our purpose was to assess the effects that fetal growth restriction exerts on the myelination of the developing brain. STUDY DESIGN: Fetal haemodynamic centralization, an adaptive strategy to growth restriction caused by placental insufficiency, was determined by Doppler ultrasonography. Infants with a raised ratio between umbilical artery pulsatility index and cerebral artery pulsatility index are severely growth restricted. Visual evoked potentials give information on the degree of brain myelination. Shortening of visual evoked potential latencies is a normal feature of myelination. In a consecutive series of 105 Neonates, visual evoked potentials were recorded at the corrected ages of 6 months and 1 years. Correction for possible confounders, such as cranial ultrasonographic findings, gestational age, and head circumference, was performed. RESULTS: At 6 months, infants with a raised umbilical artery/cerebral artery pulsatility index ratio have shorter visual evoked potential latencies. Opposite of neonates with a normal umbilical artery/cerebral artery ratio, they show no postnatal maturational shortening of visual evoked potential latencies. CONCLUSION: Accelerated neurophysiologic maturation, found in infants with a high umbilical artery/cerebral artery ratio, might be the result of a beneficial adaptive process to severe fetal growth restriction.

[Pipemidic acid in the prevention of recurring cystitis in women]. / L'acide pipémidique dans la prophylaxie des cystites récidivantes chez la femme.

The efficacy, safety and acceptability of pipemidic acid in the treatment and the prophylaxis of cystitis in women have been evaluated. After curative treatment, patients received prophylaxis using the compound for a duration of 6 months, and were followed up a further 4 month-period without specific therapy. During the prophylaxis period, no relapse was observed in over 85% of the treated patients. In 15% of cases, a pathogen reappeared along with recurrence of the preexisting symptoms. An increase to 29% of the cases was noted after the withdrawal of the treatment over a month study period. The pathogens involved in the cases of relapse during the prophylaxis period were sensitive to pipemidic acid in 1/3 of cases (6/18 cases), and resistant in 2/3 (12/18 cases) of cases. Those involved in relapses during the observation period were sensitive in 1/2 of the cases (8/16 cases), resistant or intermediate in 1/2 of the cases (8/16 cases). Thus, prophylactic treatment with pipemidic acid has a favorable influence on the number of relapses in patients with recurrent cystitis.