Wastewater contamination in Antarctic melt-water streams evidenced by virological and organic molecular markers.

Human activities in the Antarctica including tourism and scientific research have been raised substantially in the last century with the concomitant impact on the Antarctic ecosystems through the release of wastewater mainly from different scientific stations activities. The aim of this study was to assess the wastewater contamination of surface waters and sediments of three melt-water streams (11 sites) by leaking septic tanks located in the vicinity of the Uruguayan Scientific Station in the Fildes Peninsula, King George Island, Antarctica, during summer 2015. For this purpose, we combined the analysis of fecal steroids in sediments by using gas chromatography and six enteric viruses in surface waters by quantitative and qualitative PCR. Coprostanol concentrations (from 0.03 to 3.31µgg-1) and fecal steroids diagnostic ratios indicated that stations C7 and C8 located in the kitchen stream presented sewage contamination. Rotavirus was the only enteric virus detected in five sites with concentration ranging from 1.2×105gcL-1 to 5.1×105gcL-1 being three of them located downstream from the leaking AINA and Kitchen septic tanks. This study shows for the first time the presence of both virological and molecular biomarkers of wastewater pollution in surface waters and sediments of three melt-water streams in the vicinity of a scientific station in the Antarctica. These results highlight the importance of the complementation of these biomarkers in two different matrices (surface waters and sediments) to assess wastewater pollution in an Antarctic environment related to anthropogenic activities in the area.

Impact of level of expertise versus the statistical tool on vertebral fracture assessment (VFA) readings in cohort studies.

The present study tested if the accuracy of the VFA reading reproducibility is more affected by the statistical tool used or by the reader's level of expertise in 50 VFA from a population-based cohort, the OstéoLaus study. We found that uniform kappa and instruction reading with the ISCD/IOF VFA reading course both increased the accuracy of the reproducibility. INTRODUCTION: Vertebral fractures (VF) due to osteoporosis are under diagnosed. Screening osteoporosis in the general population allows improving management of fragility fracture. It consists to perform a dual X-ray absorptiometry and a spine X-ray to look at a VF. To reduce the dosage of radiation, prevalent or incident VF could be detected by DXA image. The aim of the present study was to test the reproducibility of vertebral fracture assessment (VFA) readings in a population-based cohort and to explore if the accuracy of the reproducibility is more affected by the statistical tool used or by the reader's level of expertise. METHODS: We calculated the reproducibility of VFA reading by uniform and Cohen's kappa, comparing one expert and one non-expert, before and after an instructional on-line International Society of Clinical Densitometry (ISCD) /International Osteoporosis Foundation (IOF) course on VFA reading. We performed the analysis on 50 VFA from a population-based cohort, the OstéoLaus study. RESULTS: Before the VFA reading course, reproducibility with Cohen's kappa was moderate to poor (0 to 0.520), good with the uniform kappa (0.796 to 0.958). After the course, both Cohen's kappa and uniform kappa statistically increased, ranging from 0.524 to 1.000. CONCLUSIONS: For female population-based cohort studies, we recommend using the uniform kappa and instructing a non-expert reader using the ISCD/IOF VFA reading course to correctly read and evaluate the reproducibility of the VFA reading.

PACIC Instrument: disentangling dimensions using published validation models.

OBJECTIVE: To better understand the structure of the Patient Assessment of Chronic Illness Care (PACIC) instrument. More specifically to test all published validation models, using one single data set and appropriate statistical tools. DESIGN: Validation study using data from cross-sectional survey. PARTICIPANTS: A population-based sample of non-institutionalized adults with diabetes residing in Switzerland (canton of Vaud). MAIN OUTCOME MEASURE: French version of the 20-items PACIC instrument (5-point response scale). We conducted validation analyses using confirmatory factor analysis (CFA). The original five-dimension model and other published models were tested with three types of CFA: based on (i) a Pearson estimator of variance-covariance matrix, (ii) a polychoric correlation matrix and (iii) a likelihood estimation with a multinomial distribution for the manifest variables. All models were assessed using loadings and goodness-of-fit measures. RESULTS: The analytical sample included 406 patients. Mean age was 64.4 years and 59% were men. Median of item responses varied between 1 and 4 (range 1-5), and range of missing values was between 5.7 and 12.3%. Strong floor and ceiling effects were present. Even though loadings of the tested models were relatively high, the only model showing acceptable fit was the 11-item single-dimension model. PACIC was associated with the expected variables of the field. CONCLUSIONS: Our results showed that the model considering 11 items in a single dimension exhibited the best fit for our data. A single score, in complement to the consideration of single-item results, might be used instead of the five dimensions usually described.

[Effects of nighttime and daytime interval definition on blood pressure and dipping in patients referred for ambulatory blood pressure measurement]. / Différences induites par la définition des périodes diurnes et nocturnes sur la pression artérielle et le dipping lors d'une mesure ambulatoire de la pression artérielle.

UNLABELLED: Ambulatory blood pressure monitoring (ABPM) has become indispensable for the diagnosis and control of hypertension. However, no consensus exists on how daytime and nighttime periods should be defined. OBJECTIVE: To compare daytime and nighttime blood pressure (BP) defined by an actigraph and by body position with BP resulting from arbitrary daytime and nighttime periods. PATIENTS AND METHOD: ABPM, sleeping periods and body position were recorded simultaneously using an actigraph (SenseWear Armband(®)) in patients referred for ABPM. BP results obtained with the actigraph (sleep and position) were compared to the results obtained with fixed daytime (7a.m.-10p.m.) and nighttime (10p.m.-7a.m.) periods. RESULTS: Data from 103 participants were available. More than half of them were taking antihypertensive drugs. Nocturnal BP was lower (systolic BP: 2.08±4.50mmHg; diastolic BP: 1.84±2.99mmHg, P<0.05) and dipping was more marked (systolic BP: 1.54±3.76%; diastolic BP: 2.27±3.48%, P<0.05) when nighttime was defined with the actigraph. Standing BP was higher (systolic BP 1.07±2.81mmHg; diastolic BP: 1.34±2.50mmHg) than daytime BP defined by a fixed period. CONCLUSION: Diurnal BP, nocturnal BP and dipping are influenced by the definition of daytime and nighttime periods. Studies evaluating the prognostic value of each method are needed to clarify which definition should be used.

Social reasoning skills in adults with Down syndrome: the role of language, executive functions and socio-emotional behaviour.

BACKGROUND: Although the prevalence of mental illness and behaviour problems is lower in adults with Down syndrome (DS) than in other populations with intellectual disabilities, they do present emotional and relational problems, as well as social integration difficulties. However, studies reporting on specific competences known to be central in developing appropriate social relationships (e.g. social reasoning, emotion processing, theory of mind) remain rare in the adult DS population and the mechanisms underlying these people's emotional and relational difficulties are unclear. METHOD: The present study investigated the ability to understand the appropriateness of others' social behaviour in 34 adults with DS, using the Social Resolution Task (SRT). Their results were compared with those of 34 typically developing (TD) children matched for gender and receptive vocabulary. The relationships among the SRT experimental task, cognitive competences (receptive and productive vocabulary, non-verbal reasoning, inhibition, selective attention) and a caregiver-rated measure of socio-emotional behaviour were examined in the DS group. RESULTS: The DS participants' global SRT scores did not differ from those of the controls. However, analyses of the SRT subscores revealed that the DS group identified significantly fewer inappropriate situations than the control group. Nevertheless, when they correctly identified the behaviour as inappropriate, they were as well as the controls to explain the rules underlying their responses. Regression analyses showed that receptive vocabulary and selective attention and a specific dimension of the socio-emotional profile (social relating skills) constituted the best predictors of the DS adults' performance on the SRT. CONCLUSIONS: The main findings show that the DS participants demonstrate relatively good social reasoning skills in comparison with TD children matched for verbal age. However, the two groups present distinctions in their response patterns, and the influence of cognitive variables on success on the SRT also appears different. While selective attention skills are found to be significant predictors for both groups, the influence of receptive vocabulary level is much stronger in the DS group. The implications of particular cognitive and socio-emotional factors for success on the SRT in this group are considered in more detail.