Compositional analysis of the association between mortality and 24-hour movement behaviour from NHANES

Aims:Previous prospective studies of the association between mortality and physical activity have generally not fully accounted for the interplay between movement behaviours. A compositional data modelling approach accounts for relative scale and co-dependency in time-use data across physical activity behaviours of the 24-hour day. Methods:A prospective analysis of the National Health and Nutrition Examination Survey 2005-2006 on N = 1468 adults (d = 135 deaths) in ages 50-79 years was undertaken using compositional Cox regression analysis. Daily time spent in sedentary behaviour, light intensity (LIPA) and moderate-to-vigorous physical activity (MVPA) was determined from waist-mounted accelerometer data (Actigraph 7164) and supplemented with self-reported sleep data to determine the daily time-use composition. Results:The composition of time spent in sedentary behaviour, LIPA, MVPA and sleep was associated with mortality rate after allowing for age and sex effects (p < 0.001), and remained significant when other lifestyle factors were added (p < 0.001). This was driven primarily by the preponderance of MVPA; however, significant changes are attributable to LIPA relative to sedentary behaviour and sleep, and sedentary behaviour relative to sleep. The final ratio ceased to be statistically significant after incorporating lifestyle factors. The preponderance of MVPA ceased to be statistically significant after incorporating health at outset and physical limitations on movement. Conclusions: An association is inferred between survival rate and the physical activity composition of the day. The MVPA time share is important, but time spent in LIPA relative to sedentary behaviour and sleep is also a significant factor. Increased preponderance of MVPA may have detrimental associations at higher levels of MVPA

Differences in context-specific sedentary behaviors according to weight status in adolescents, adults and seniors: a compositional data analysis

To develop effective sedentary behavior interventions aimed at people who are overweight/obese, detailed insight is needed into the contexts of sedentary behavior of these people. Therefore, the aims of this study were to describe the composition of sedentary behavior and to compare context-specific sedentary behaviors between different weight groups. Cross-sectional data were used from a study conducted in 2013-2014 among a Flemish sample of adolescents (n = 513), adults (n = 301), and seniors (n = 258). Sixteen context-specific sedentary behaviors were assessed using a validated questionnaire during the week and weekend. Compositional descriptive statistics were performed to determine the relative contribution of context-specific sedentary behaviors in the three age groups. Compositional multivariate analysis of covariance and pairwise comparisons were conducted to examine weight group differences in context-specific sedentary behaviors. The compositional means indicated that the highest proportion of sedentary time was spent at school, at work, and while watching television. Statistically significant differences were found in the composition of sedentary behaviors between healthy weight and overweight/obese participants. In all age groups, socially engaging sedentary behaviors were more prevalent in healthy weight people, whereas socially disengaging behaviors were more prevalent in overweight/obese people. Consequently, the findings of this study suggest that future overweight/obesity interventions should no longer focus on total sedentary time, as not all context-specific sedentary behaviors are associated with overweight/obesity. Instead, it might be better to target specific contexts of sedentary behaviorspreferably those less socially engagingwhen aiming to reduce overweight/obesity

Olive oil nutritional labeling by using Vis/NIR spectroscopy and compositional statistical methods

Food nutritional labeling is compulsory in the European Union since 13 December 2016. The olive oil fatty acid composition shows high variation depending mainly on the variety. Thus, olive oil nutritional labeling is problematic for the industry. Besides, the analysis of all batches of olive oil using the official methods is expensive. Therefore, the olive oil industry is seriously concerned about solutions for nutritional labeling. In this study, a new rapid technique to measure the nutrients for the olive oil nutritional labeling, is assessed. A novel partial least squares (PLS) calibration model using log-ratio coordinates has been formulated and successfully tested for predicting the percentages of monounsaturated, saturated, and polyunsaturated fatty acids based on visible and near infrared spectroscopy. The model provided accuracy suitable for labeling, under the rules in force in the European Union. The error was generally much lower than the tolerance. Industrial relevance: The approach here proposed can be a suitable solution for olive oil nutritional labeling, which is a current challenge for the olive oil industry.Consejo Superior de Investigaciones Científicas 20137R065Ministerio de Economía y Competitividad MTM2015-65016-C2-1(2)-

A novel technique for retrospective genetic analysis of the response to vaccination or infection using cell-free DNA from archived sheep serum and plasma

Genetic variation is associated with differences in disease resistance and susceptibility among individuals within a population. To date, molecular genetic analyses of host responses have relied on extraction of genomic DNA from whole blood or tissue samples. However, such samples are not routinely collected during large-scale field studies. We demonstrate that cell-free genomic DNA (cfDNA) may be extracted and amplified from archived plasma samples, allowing retrospective analysis of host genetic diversity. This technique was also applicable to archived serum samples up to 35 years old and to different ruminant species. As proof of concept, we used this cfDNA approach to genotype the major histocompatibility complex (MHC) class II DRB1 locus of 224 Merino sheep which had participated in field trials of a commercial Haemonchus contortus vaccine, Barbervax®, in Australia. This identified a total of 51 different DRB1 alleles and their relative frequencies. This is the first study to examine host MHC diversity using DNA extracted from archived plasma samples, an approach that may be applied to retrospective analyses of genetic diversity and responses to vaccination or infection across different species and populations

Compositional analysis of the associations between 24-h movement behaviours and health indicators among adults and older adults from the Canadian health measure survey

This study investigated the association between the allocation of time-use over the 24-h day between sleep, sedentary behaviour (SB), light-intensity physical activity (LPA) and moderate-to-vigorous-intensity physical activity (MVPA)) and health indicators. A cross-sectional analysis of Canadian Health Measures Survey data was undertaken using compositional data analysis. SB, LPA and MVPA were derived from Actical accelerometers, whilst sleep was self-reported by respondents. The analysis was stratified by age; adults (aged 18⁻64 years; n = 6322) and older adults (65⁻79 years; n = 1454). For adults, beneficial associations were observed between larger proportions of MVPA relative to time in other behaviours and body mass index (BMI), waist circumference, aerobic fitness, resting heart rate, high-density lipoprotein (HDL) cholesterol, triglycerides, blood glucose and insulin levels. More time spent in sleep relative to other movement behaviours was deleteriously associated with aerobic fitness, HDL cholesterol, insulin, C-reactive proteins and grip strength but beneficially with low-density lipoprotein cholesterol. Relative time spent in LPA was deleteriously associated with BMI and beneficially with triglycerides and grip strength. In older adults, these associations were blunted or disappeared but larger proportions of MVPA were associated with better mental health. The importance to health of MVPA when explicitly considered relative to other movement behaviours was confirmed

Is high aerobic workload at work associated with leisure time physical activity and sedentary behaviour among blue-collar workers? A compositional data analysis based on accelerometer data

ObjectiveThis study aimed to investigate the hypothesized negative association between duration of work time spent at a high relative aerobic workload and leisure time movement behaviours among blue-collar workers.MethodsThis was a cross-sectional study based on heart rate and accelerometer data from 803 blue-collar workers (447 men and 356 women). Relative aerobic workload was measured as percentage of heart rate reserve during work (%HRR). Leisure time movement behaviours were expressed in terms of leisure time spent in sedentary and active behaviours in uninterrupted bouts (i.e. 30 min). Compositional regression and isotemporal substitution models were used to assess the association between the predominance of work time spent at ≥40%HRR and leisure time spent in sedentary and active bouts. All analyses were stratified by sex.ResultsFor men, there was no statistically significant association between the predominance of work time spent at ≥40%HRR and leisure time movement behaviours. Among women, the predominance of ≥40%HRR at work was negatively associated with relative leisure time spent in ≥10 min bouts of active behaviour ([Formula: see text] = -0.21, p = 0.02) and a theoretical 15 min reallocation of work time from ConclusionOur result highlights the need for considering work-related barriers for an active leisure time in high-risk populations. Longitudinal studies are warranted to disentangle the relationship between physically demanding work characteristics and leisure time movement behaviours in such populations

The extent of placental pathology is negatively correlated to birth weight in ewes infected with the wild-type strain of Chlamydia abortus

The placenta is the organ that allows the exchange of oxygen and nutrients between maternal and foetal blood, supplying the requirements of the growing foetus. Consequently, any factor that alters placental integrity may affect foetal nutrition, viability and lamb birth weight. Reproductive diseases, such as ovine enzootic abortion (OEA), impact on foetal viability due to the reduction in the functional area for maternofoetal exchange. This study aimed to consider the impact of pathological features of OEA placental lesions on lamb birth weight and indirectly on foetal viability. To investigate the relationship between birth weight and various OEA-related parameters, data from 562 lambs/foetuses from animals experimentally challenged with Chlamydia abortus strain S26/3 and from uninfected animals were analysed. The parameters investigated included the number of foetuses/lambs delivered (single/multiple), foetus/lamb sex, length of gestation, the proportion of placentas affected by lesions (percentage of gross placental pathology), foetal viability (live/aborted) and the number of C. abortus organisms shed in post-parturition vaginal excretions. The results suggest that the length of gestation and the proportion of placentas affected by lesions are the main contributors to birth weight variability, whereas the other factors, including foetal viability (live or aborted outcomes), were found to be less relevant co-variables. The study determined the strongest positive and negative correlations between birth weight were with the length of gestation and the extent of placental pathology, respectively. These results may indicate that economic losses associated with OEA infections result not only from aborted foetuses but also from the surviving lambs that are born weaker and consequently are more susceptible to diseases.EEA MercedesFil: Caspe, Sergio Gaston. Moredun Research Institute; Reino UnidoFil: Caspe, Sergio Gaston. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mercedes; ArgentinaFil: Caspe, Sergio Gaston. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Palarea-Albaladejo, Javier. Biomathematics & Statistics Scotland; Reino UnidoFil: Palarea-Albaladejo, Javier. University of Girona. Deparment of Computer Sciences, Applied Mathematics and Statistics; EspañaFil: Livingstone, Morag. Moredun Research Institute; Reino UnidoFil: Wattegedera, Sean Ranjan. Moredun Research Institute; Reino UnidoFil: Milne, Elspeth. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Sargison, Neil Donald. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Longbottom, David. Moredun Research Institute; Reino Unid

A novel, high-welfare methodology for evaluating poultry red mite interventions in vivo

Optimisation and use of a device for the on-hen in vivo feeding of all hematophagous stages of Dermanyssus gallinae is described. The sealed mesh device contains the mites and is applied to the skin of the hen’s thigh where mites can feed on the bird through a mesh which has apertures large enough to allow the mites’ mouth-parts to access to the bird but small enough to contain the mites. By optimising the depth and width of the mesh aperture size we have produced a device which will lead to both reduction and refinement in the use of animals in research, allowing the pre-screening of new vaccines and systemic acaricides/insecticides which have been developed for the control of these blood-feeding parasites before progressing to large field trials. For optimal use,the device should be constructed from 105μm aperture width, 63 μm depth, polyester mesh and the mites (irrespective of life stage) should be conditioned with no access to food for 3 weeks at 4 °C for optimal feeding and post-feeding survival