895 resultados para time and movements
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Spatio-temporal variability in settlement and recruitment, high mortality during the first life-history stages, and selection may determine the genetic structure of cohorts of long-lived marine invertebrates at small scales. We conducted a spatial and temporal analysis of the common Mediterranean Sea urchin Paracentrotus lividus to determine the genetic structure of cohorts at different scales. In Tossa de Mar (NW Mediterranean), recruitment was followed over 5 consecutive springs (2006-2010). In spring 2008, recruits and two-year-old individuals were collected at 6 locations along East and South Iberian coasts separated from 200 to over 1,100 km. All cohorts presented a high genetic diversity based on a fragment of mtCOI. Our results showed a marked genetic homogeneity in the temporal monitoring and a low degree of spatial structure in 2006. In 2008, coupled with an abnormality in the usual circulation patterns in the area, the genetic structure of the southern populations studied changed markedly, with arrival of many private haplotypes. This fact highlights the importance of point events in renewing the genetic makeup of populations, which can only be detected through analysis of the cohort structure coupling temporal and spatial perspectives.
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Tämä työ luo katsauksen ajallisiin ja stokastisiin ohjelmien luotettavuus malleihin sekä tutkii muutamia malleja käytännössä. Työn teoriaosuus sisältää ohjelmien luotettavuuden kuvauksessa ja arvioinnissa käytetyt keskeiset määritelmät ja metriikan sekä varsinaiset mallien kuvaukset. Työssä esitellään kaksi ohjelmien luotettavuusryhmää. Ensimmäinen ryhmä ovat riskiin perustuvat mallit. Toinen ryhmä käsittää virheiden ”kylvöön” ja merkitsevyyteen perustuvat mallit. Työn empiirinen osa sisältää kokeiden kuvaukset ja tulokset. Kokeet suoritettiin käyttämällä kolmea ensimmäiseen ryhmään kuuluvaa mallia: Jelinski-Moranda mallia, ensimmäistä geometrista mallia sekä yksinkertaista eksponenttimallia. Kokeiden tarkoituksena oli tutkia, kuinka syötetyn datan distribuutio vaikuttaa mallien toimivuuteen sekä kuinka herkkiä mallit ovat syötetyn datan määrän muutoksille. Jelinski-Moranda malli osoittautui herkimmäksi distribuutiolle konvergaatio-ongelmien vuoksi, ensimmäinen geometrinen malli herkimmäksi datan määrän muutoksille.
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BACKGROUND AND AIMS: Evidence-based and reliable measures of addictive disorders are needed in general population-based assessments. One study suggested that heavy use over time (UOT) should be used instead of self-reported addiction scales (AS). This study compared UOT and AS regarding video gaming and internet use empirically, using associations with comorbid factors. DESIGN: Cross-sectional data from the 2011 French Survey on Health and Consumption on Call-up and Preparation for Defence-Day (ESCAPAD), cross-sectional data from the 2012 Swiss ado@internet.ch study and two waves of longitudinal data (2010-13) of the Swiss Longitudinal Cohort Study on Substance Use Risk Factors (C-SURF). SETTING: Three representative samples from the general population of French and Swiss adolescents and young Swiss men, aged approximately 17, 14 and 20 years, respectively. PARTICIPANTS: ESCAPAD: n =22 945 (47.4% men); ado@internet.ch: n =3049 (50% men); C-SURF: n =4813 (baseline + follow-up, 100% men). MEASUREMENTS: We assessed video gaming/internet UOT ESCAPAD and ado@internet.ch: number of hours spent online per week, C-SURF: latent score of time spent gaming/using internet] and AS (ESCAPAD: Problematic Internet Use Questionnaire, ado@internet.ch: Internet Addiction Test, C-SURF: Gaming AS). Comorbidities were assessed with health outcomes (ESCAPAD: physical health evaluation with a single item, suicidal thoughts, and appointment with a psychiatrist; ado@internet.ch: WHO-5 and somatic health problems; C-SURF: Short Form 12 (SF-12 Health Survey) and Major Depression Inventory (MDI). FINDINGS: UOT and AS were correlated moderately (ESCAPAD: r = 0.40, ado@internet.ch: r = 0.53 and C-SURF: r = 0.51). Associations of AS with comorbidity factors were higher than those of UOT in cross-sectional (AS: .005 ≤ |b| ≤ 2.500, UOT: 0.001 ≤ |b| ≤ 1.000) and longitudinal analyses (AS: 0.093 ≤ |b| ≤ 1.079, UOT: 0.020 ≤ |b| ≤ 0.329). The results were similar across gender in ESCAPAD and ado@internet.ch (men: AS: 0.006 ≤ |b| ≤ 0.211, UOT: 0.001 ≤ |b| ≤ 0.061; women: AS: 0.004 ≤ |b| ≤ 0.155, UOT: 0.001 ≤ |b| ≤ 0.094). CONCLUSIONS: The measurement of heavy use over time captures part of addictive video gaming/internet use without overlapping to a large extent with the results of measuring by self-reported addiction scales (AS). Measuring addictive video gaming/internet use via self-reported addiction scales relates more strongly to comorbidity factors than heavy use over time.
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Trophic ecology and movements are critical issues for understanding the role of marine predators in food webs and for facing the challenges of their conservation. Seabird foraging ecology has been increasingly studied, but small elusive species, such as those forming the"little shearwater" complex, remain poorly known. We present the first study on the movements and feeding ecology of the Barolo shearwater Puffinus baroli baroli in a colony from the Azores archipelago (NE Atlantic), combining global location-sensing units, stable isotope analyses of feathers (δ13C and δ15N), stomach flushings and data from maximum depth gauges. During the chick-rearing period, parents visited their nests most nights, foraged mainly south of the colony and fed at lower trophic levels than during the non-breeding period. Squid was the most diverse prey (6 families and at least 10 different taxa), but species composition varied considerably between years. Two squid families, Onychoteuthidae and Argonautidae, and the fish family Phycidae accounted for 82.3% of ingested prey by number. On average, maximum dive depths per foraging trip reached 14.8 m (range: 7.9 to 23.1 m). After the breeding period, birds dispersed offshore in all directions and up to 2500 km from the breeding colony, and fed at higher trophic levels. Overall, our results indicate that the Barolo shearwater is a non-migratory shearwater feeding at the lowest trophic level among Macaronesian seabirds, showing both diurnal and nocturnal activity and feeding deeper in the water column, principally on small schooling squid and fish. These traits contrast with those of 3 other Azorean Procellariiformes (Cory"s shearwater Calonectris diomedea, the Madeiran storm-petrel Oceanodroma castro and Monteiro"s storm-petrel O. monteiroi), indicating ecological segregation within the Azorean seabird community.
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Abstract Background: Little is known about how sitting time, alone or in combination with markers of physical activity (PA), influences mental well-being and work productivity. Given the need to develop workplace PA interventions that target employees’ health related efficiency outcomes; this study examined the associations between self-reported sitting time, PA, mental well-being and work productivity in office employees. Methods: Descriptive cross-sectional study. Spanish university office employees (n = 557) completed a survey measuring socio-demographics, total and domain specific (work and travel) self-reported sitting time, PA (International Physical Activity Questionnaire short version), mental well-being (Warwick-Edinburg Mental Well-Being Scale) and work productivity (Work Limitations Questionnaire). Multivariate linear regression analyses determined associations between the main variables adjusted for gender, age, body mass index and occupation. PA levels (low, moderate and high) were introduced into the model to examine interactive associations. Results: Higher volumes of PA were related to higher mental well-being, work productivity and spending less time sitting at work, throughout the working day and travelling during the week, including the weekends (p < 0.05). Greater levels of sitting during weekends was associated with lower mental well-being (p < 0.05). Similarly, more sitting while travelling at weekends was linked to lower work productivity (p < 0.05). In highly active employees, higher sitting times on work days and occupational sitting were associated with decreased mental well-being (p < 0.05). Higher sitting times while travelling on weekend days was also linked to lower work productivity in the highly active (p < 0.05). No significant associations were observed in low active employees. Conclusions: Employees’ PA levels exerts different influences on the associations between sitting time, mental well-being and work productivity. The specific associations and the broad sweep of evidence in the current study suggest that workplace PA strategies to improve the mental well-being and productivity of all employees should focus on reducing sitting time alongside efforts to increase PA.
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ABSTRACT In experiments conducted in a growth chamber, the chronological time and the accumulated degree-days were determined for the duration of incubation, latent and infectious periods of Phakopsora pachyrhizi cultivars BRSGO 7560 and BRS 246 RR. Detached soybean leaflets were placed in gerbox-type acrylic boxes and inoculated with 20 x 103 uredospores/mL. The study was conducted at 12-h photoperiod and temperatures of 10ºC, 15ºC, 22ºC, 25ºC and 30°C for 30 days. Lesions and uredia/cm2were evaluated and the number of uredia per lesion was quantified after the beginning of sporulation. The sporulation potential was also quantified for cultivars BRSGO 7560 and BRS 246 RR. The steps of the infection process can be quantified based on both the chronological time and the accumulated heat. The cultivar BRSGO 7560 produced 4,012.8 spores/cm2 and BRS 246 RR, 7,348.4 uredospores/cm2. The largest number of uredia was produced at 25ºC in both cultivars; however, BRS 246 RR presented 372.7 uredia/cm2 and BRSGO 7560, 231.6 uredia/cm2. At 10ºC and 30°C, leaf infection did not occur in both cultivars.
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This study aimed to evaluate the influence of airflow (0.25, 0.50 and 0.75 L.L-1.min-1) and cycle time (10.45 h, 14.25 h and 17.35 h) on a sequencing batch reactor (SBR) performance in promoting nitrification and denitrification of poultry slaughterhouse wastewater. The operational stages included feeding, aerobic and anoxic reactions, sedimentation and discharge. SBR was operated in a laboratory scale with a working volume of 4 L, keeping 25% of biomass retained inside the reactor as inoculum for the next batch. In the anoxic stage, C: N ratio was maintained between 5 and 6 by adding cassava starch wastewater. A factorial design (22) with five repetitions was designed at the central point to evaluate the influence of cycle time and airflow on total inorganic nitrogen removal (N-NH4++N-NO2-+N-NO3-) and in the whole process (nitrification and denitrification). The highest total inorganic nitrogen removal (93.3%) was observed for airflow of 0.25 L.L-1.min‑1 and a cycle time of 14.25 h. At the end of the experiment, the sludge inside the reactor was characterized by fluorescent in situ hybridization (FISH), indicating the presence of ammonia and nitrite oxidizing bacteria.
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Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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The survival of hemodialysis patients is likely to be influenced not only by well-known risk factors like age and comorbidity, but also by changes in dialysis technology and practices accumulated along time. We compared the survival curves, dialysis routines and some risk factors of two groups of patients admitted to a Brazilian maintenance hemodialysis program during two consecutive decades: March 1977 to December 1986 (group 1, N = 162) and January 1987 to June 1997 (group 2, N = 237). The median treatment time was 22 months (range 1-198). Survival curves were constructed using the Kaplan-Meier method and compared using the log-rank method. The Cox proportional hazard regression model was used to investigate the more important variables associated with outcome. The most important changes in dialysis routine and in patient care during the total period of observation were the progressive increase in the dose of dialysis delivered, the prohibition of potassium-free dialysate, the use of bicarbonate as a buffer and the upgrading of the dialysis equipment. There were no significant differences between the survival curves of the two groups. Survival rates at 1, 5 and 10 years were 84, 53 and 29%, respectively, for group 1 and 77, 42 and 21% for group 2. Patients in group 1 were younger (45.5 ± 15.2 vs 55.2 ± 15.9 years, P<0.001) and had a lower prevalence of diabetes (11.1 vs 27.4%, P<0.001) and of cardiovascular disease (9.3 vs 20.7%, P<0.001). According to the Cox multivariate model, only age (hazard ratio (HR) 1.04, confidence interval (CI) 1.03-1.05, P<0.001) and diabetes (HR 2.55, CI 1.82-3.58, P<0.001) were independent predictors of mortality for the whole group. Patients of group 2 had a lower prevalence of sudden death (19.1 vs 9.7%, P<0.001). After adjusting for age, diabetes and other mortality risk factors, the risk of death was 17% lower in group 2, although this difference was not statistically significant. We conclude that the negative effects of advanced age and of higher frequency of comorbidity on the survival of group 2 patients were probably offset by improvements in patient care and in the quality and dose of dialysis delivered, so that the survival curves did not undergo significant changes along time.
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The aim of the present study was to compare heart rate variability (HRV) at rest and during exercise using a temporal series obtained with the Polar S810i monitor and a signal from a LYNX® signal conditioner (BIO EMG 1000 model) with a channel configured for the acquisition of ECG signals. Fifteen healthy subjects aged 20.9 ± 1.4 years were analyzed. The subjects remained at rest for 20 min and performed exercise for another 20 min with the workload selected to achieve 60% of submaximal heart rate. RR series were obtained for each individual with a Polar S810i instrument and with an ECG analyzed with a biological signal conditioner. The HRV indices (rMSSD, pNN50, LFnu, HFnu, and LF/HF) were calculated after signal processing and analysis. The unpaired Student t-test and intraclass correlation coefficient were used for data analysis. No statistically significant differences were observed when comparing the values analyzed by means of the two devices for HRV at rest and during exercise. The intraclass correlation coefficient demonstrated satisfactory correlation between the values obtained by the devices at rest (pNN50 = 0.994; rMSSD = 0.995; LFnu = 0.978; HFnu = 0.978; LF/HF = 0.982) and during exercise (pNN50 = 0.869; rMSSD = 0.929; LFnu = 0.973; HFnu = 0.973; LF/HF = 0.942). The calculation of HRV values by means of temporal series obtained from the Polar S810i instrument appears to be as reliable as those obtained by processing the ECG signal captured with a signal conditioner.
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The efficiency of four Sanitizers - peracetic acid, chlorhexidine, quaternary ammonium, and organic acids - was tested in this work using different bacteria recognized as a problem to meat industry, Salmonella sp., S. aureus, E. coli and L. monocytogenes. The effects of sanitizer concentration (0.2, 0.5, 0.6, 1.0, 1.1 and 1.4%), at different temperatures (10 and 45 °C) and contact time (2, 10, 15, 18 and 25 minutes) were evaluated. Tests in an industrial plant were also carried out considering previously obtained results. In a general way, peracetic acid presented higher efficiencies using low concentration (0.2%) and contact time (2 minutes) at 10 °C. The tests performed in industrial scale showed that peracetic acid presented a good performance in concentration and contact time lower than that suggested by the suppliers. The use of chlorhexidine and quaternary ammonium led to reasonable results at the indicated conditions, and organic acids were ineffective under concentration and contact time higher than those indicated by the suppliers in relation to Staphylococcus aureus. The results, in general, show that the choice for the most adequate sanitizer depends on the microorganism contaminant, the time available for sanitizer application, and also on the process cost.
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AbstractThis study aimed to evaluate the effect of the distillation time and the sample mass on the total SO2 content in integral passion fruit juice (Passiflora sp). For the SO2 analysis, a modified version of the Monier-Williams method was used. In this experiment, the distillation time and the sample mass were reduced to half of the values proposed in the original method. The analyses were performed in triplicate for each distilling time x sample mass binomial, making a total of 12 tests, which were performed on the same day. The significance of the effects of the different distillation times and sample mass were evaluated by applying one-factor analysis of variance (ANOVA). For a 95% confidence limit, it was found that the proposed amendments to the distillation time, sample mass, and the interaction between distilling time x sample mass were not significant (p > 0.05) in determining the SO2 content in passion fruit juice. In view of the results that were obtained it was concluded that for integral passion fruit juice it was possible to reduce the distillation time and the sample mass in determining the SO2 content by the Monier-Williams method without affecting the result.