A longitudinal evaluation of the resilient families randomized trial to prevent early adolescent depressive symptoms

This study aimed to evaluate whether an intervention prevented the development of depressive symptoms through the early years of secondary school (Grades 7 to 9 - mean ages 12.3 to 14.5 years) in Victoria, Australia. Twelve schools were randomized to a universal preventative intervention (including a student social relationship/emotional health curriculum, and parent/caregiver parenting education); 12 were randomized as control schools. Multivariate regression analyses used student self-report to predict depressive symptoms at 26-month follow-up (13-months after intervention completion) from baseline measures and intervention status (N = 2027). There was no overall intervention effect on depressive symptoms. However, intervention students with moderate symptoms whose parents attended parent education events had a significantly reduced risk of depressive symptoms at follow-up. Future evaluations of interventions of this type should investigate: therapeutic processes; methods to increase recruitment into effective parent education events; and the potential to target assistance to students with high depressive symptoms.

Western diet is associated with a smaller hippocampus: a longitudinal investigation

Background: Recent meta-analyses confirm a relationship between diet quality and both depression and cognitive health in adults. While the biological pathways that underpin these relationships are likely multitudinous, extensive evidence from animal studies points to the involvement of the hippocampus. The aim of this study was to examine the association between dietary patterns and hippocampal volume in humans, and to assess whether diet was associated with differential rates of hippocampal atrophy over time. Methods: Data were drawn from the Personality and Total Health Through Life Study and focused on a subsample of the cohort (n = 255) who were aged 60-64 years at baseline in 2001, completed a food frequency questionnaire, and underwent two magnetic resonance imaging scans approximately 4 years apart. Longitudinal generalized estimating equation linear regression models were used to assess the association between dietary factors and left and right hippocampal volumes over time. Results: Every one standard deviation increase in healthy "prudent" dietary pattern was associated with a 45.7 mm³ (standard error 22.9 mm³) larger left hippocampal volume, while higher consumption of an unhealthy "Western" dietary pattern was (independently) associated with a 52.6 mm³ (SE 26.6 mm³) smaller left hippocampal volume. These relationships were independent of covariates including age, gender, education, labour-force status, depressive symptoms and medication, physical activity, smoking, hypertension and diabetes. While hippocampal volume declined over time, there was no evidence that dietary patterns influenced this decline. No relationships were observed between dietary patterns and right hippocampal volume. Conclusions: Lower intakes of nutrient-dense foods and higher intakes of unhealthy foods are each independently associated with smaller left hippocampal volume. To our knowledge, this is the first human study to demonstrate associations between diet and hippocampal volume concordant with data previously observed in animal models.

A longitudinal analysis of changes in job control and mental health

Deteriorating job control has been previously shown to predict poor mental health. The impact of improvement in job control on mental health is less well understood, yet it is of policy significance. We used fixed-effects longitudinal regression models to analyze 10 annual waves of data from a large Australian panel survey (2001-2010) to test within-person associations between change in self-reported job control and corresponding change in mental health as measured by the Mental Component Summary score of Short Form 36. We found evidence of a graded relationship; with each quintile increase in job control experienced by an individual, the person's mental health increased. The biggest improvement was a 1.55-point increase in mental health (95% confidence interval: 1.25, 1.84) for people moving from the lowest (worst) quintile of job control to the highest. Separate analyses of each of the component subscales of job control-decision authority and skill discretion-showed results consistent with those of the main analysis; both were significantly associated with mental health in the same direction, with a stronger association for decision authority. We conclude that as people's level of job control increased, so did their mental health, supporting the value of targeting improvements in job control through policy and practice interventions.

A longitudinal analysis of self-prescribed complementary and alternative medicine use by a nationally representative sample of 19,783 Australian women, 2006-2010

BACKGROUND: Complementary and alternative medicine (CAM) use is increasingly popular amongst general populations around the world with women constituting substantial CAM users. However, self-prescribed CAM use does raise potential safety concerns and so it is important to identify those risk factors associated with self-prescribed CAM use. METHODS: Data was obtained from the Australian Longitudinal Study on Women's Health (ALSWH). Longitudinal data analyses were conducted on questionnaire data from the 1973-78 cohort (n=9,145) and the 1946-51 cohort (n=10,638), collected over the period 2006-2010. RESULTS: In the 1973-78 cohort, use of self-prescribed CAM was 73.2% in 2006 and 75.3% in 2009. For the 1946-51 cohort, use of self-prescribed CAM was 73.9% in 2007 and 74.7% in 2010. There were similar levels of use of individual self-prescribed CAM, with the exception that the use of herbal medicine was much higher among the 1946-51 cohort (20% vs. 27%). There was a substantial increase over three years in the use of vitamins/minerals in both cohorts (21% and 19%, respectively). In contrast, there was a considerable decline over three years in use of aromatherapy oils in both cohorts (34% and 28%, respectively). CONCLUSION: Self-prescribed CAM use is popular amongst women in Australia and it is important that conventional practitioners providing women's health care be cognizant of such use amongst their patients. In order to ensure effective practice, there is a need for further research to explore women's decision-making and experiences around self-prescribed CAM use.

Change of school in early adolescence and adverse obesity-related dietary behavior: a longitudinal cohort study, Victoria, Australia, 2013-2014

INTRODUCTION: Environments that facilitate energy-dense, nutrient-poor diets are associated with childhood obesity. We examined the effect of a change of school environment on the prevalence of obesity and related dietary behavior in early adolescence. METHODS: Fifteen schools in Victoria, Australia, were recruited at random from the bottom 2 strata of a 5-level socioeconomic scale. In 9 schools, students in grade 6 primary school transitioned to different schools for grade 7 secondary school, whereas in 6 schools, students remained in the same school from grade 6 to grade 7. Time 1 measures were collected from students (N = 245) in grade 6 (aged 11-13 y). Time 2 data were collected from 243 (99%) of the original cohort in grade 7. Data collected were dietary recall self-reported by students via questionnaire, measured height and weight of students, and aspects of the school food environment via school staff survey. Comparative and mixed model regression analyses were conducted. RESULTS: Of 243 students, 63% (n = 152) changed schools from time 1 to time 2, with no significant difference in weight status. Students who changed schools reported an increase in purchases of after-school snack food, greater sweetened beverage intake, fewer fruit-and-vegetable classroom breaks, and less encouragement for healthy eating compared with students who remained in the same school. School staff surveys showed that more primary than secondary schools had written healthy canteen policies and fewer days of canteen or food services operation. CONCLUSION: A change of school environment has negative effects on children's obesity-related dietary behavior. Consistent policy is needed across school types to support healthy eating in school environments.

The longitudinal effects of adolescent volunteering on secondary school completion and adult volunteering

 This study explores the longitudinal effect of adolescent volunteering behaviour on young adult volunteering and the completion of secondary school. Utilising data from the Australian sample of the International Youth Development Study, frequency of volunteering in Grade 9 (mean age = 15 years) and in young adulthood (mean age = 21 years), and completion of secondary school were measured. Mixed effect logistic regression analyses revealed that adolescent volunteering was associated with an increased likelihood of volunteering in young adulthood (Odds Ratio [OR] 1.29; 95% Confidence Interval [CI] 1.20–1.39; N = 2,648) and of Grade 12 completion (OR 1.14; CI 1.03–1.28; N = 2,648), after controlling for family socioeconomic status and adolescent school adjustment. These findings suggest that adolescent volunteering may lead to further involvement in young adult volunteering and have a positive effect on school completion.

Developmental trajectories of adolescent cannabis use and their relationship to young adult social and behavioural adjustment: a longitudinal study of Australian youth

This study aimed to identify distinct developmental trajectories (sub-groups of individuals who showed similar longitudinal patterns) of cannabis use among Australian adolescents, and to examine associations between trajectory group membership and measures of social and behavioural adjustment in young adulthood. Participants (n=852, 53% female) were part of the International Youth Development Study. Latent class growth analysis was used to identify distinct trajectories of cannabis use frequency from average ages 12 to 19, across 6 waves of data. Logistic regression analyses and analyses of covariance were used to examine relationships between trajectory group membership and young adult (average age: 21) adjustment, controlling for a range of covariates. Three trajectories were identified: abstainers (62%), early onset users (11%), and late onset occasional users (27%). The early onset users showed a higher frequency of antisocial behaviour, violence, cannabis use, cannabis-related harms, cigarette use, and alcohol harms, compared to the abstinent group in young adulthood. The late onset occasional users reported a higher frequency of cannabis use, cannabis-related harms, illicit drug use, and alcohol harms, compared to the abstinent group in young adulthood. There were no differences between the trajectory groups on measures of employment, school completion, post-secondary education, income, depression/anxiety, or alcohol use problems. In conclusion, early onset of cannabis use, even at relatively low frequency during adolescence, is associated with poorer adjustment in young adulthood. Prevention and intervention efforts to delay or prevent uptake of cannabis use should be particularly focussed on early adolescence prior to age 12.

Transforming the SF-36 to account for death in longitudinal studies with three-year follow-up

BACKGROUND: Analyses of longitudinal health-related quality of life data often exclude participants who die, which limits the generalizability of the results. Methods to incorporate death as a valid score in the Medical Outcomes Study Short-Form (SF-36) have been suggested but need to be evaluated in other populations. OBJECTIVES: We sought to apply a method of transforming the SF-36 Physical Component Score (PCS) to include death. A transformation to estimate the probability of being "healthy" in 3 years, based on the current PCS value, will be developed and validated. SUBJECTS: Women in the Australian Longitudinal Study on Women's Health (ALSWH), ages 70-75 years at Survey 1 in 1996 (n = 12,432), were followed-up at 3 yearly intervals for 6 years. RESULTS: The transformation derived from the ALSWH data provides evidence that the methodology for transforming the PCS to account for deaths is sound. The 3-year equation provided good estimates of the probability of being healthy in 3 years and the method allowed deaths to be included in an analysis of changes in health over time. CONCLUSIONS: For longitudinal studies involving the SF-36 in which subjects have died, we support the recommendation that both the PCS and its transformed value which includes deaths should be analyzed to examine the influence of deaths on the study conclusions. Using study data to derive empirical parameters for the transformations may be appropriate for studies with follow-up intervals of other lengths.

Análise espacial da distribuição longitudinal de sementes de milho em uma semeadora-adubadora de precisão

In the operation of sowing with planter numerous factors interfere with the establishment of the plant stand, among them, the longitudinal distribution of seeds depending on the displacement speed can significantly affect crop productivity.The present study aimed the evaluation of longitudinal distribution of maize seeds in two different speeds of dislocation of a precision grain drill, through classical and geostatistics. A regular grid sample, totalizing 100 points in each area, was built with 10-meter distance among the points. Each sample point comprised 3.6m(2) (1.8 x 2.0) where the percentage of acceptable, double and fail spacing among the plants was measured after sowing at 4.58 and 5.94 km h(-1) speed of dislocation. Classical and geostatistics were used for data analyses. The percentage of acceptable and failed spacing has shown significant difference between 4.58 and 5.94 km h(-1) speed. The results has shown absence of spatial dependence regarding the percentage of the studied spacing (acceptable, fail and double) at both speeds, showing that studies and statistical inferences can occur based on parameters of classical statistics for distances higher than the shortest one used in the sampling.

Correlation between morphology and function of the upper lip: a longitudinal evaluation

In order to evaluate the relationship between the morphology of the upper lip and muscle activity in a sample of 38 subjects (17 males and 21 females) with Angle Class II division 1 malocclusions, cephalometric and electromyographic analyses were conducted. The sample was subdivided into either predominantly nose or mouth breathers. The individuals were evaluated at two different periods, with a 2 year interval. At the first observation, the subjects were 11 years to 14 years 11 months of age and at the second observation, 13 years 4 months to 16 years 6 months of age. Height and thickness of the upper lip were measured on lateral cephalograms with the aid of a digital pachymeter. For each individual, electromyographic records were obtained of the orbicularis oris superior muscle at rest and in a series of 12 movements. The electromyographic data were normalized as a function of amplitude, for achievement of the percentage value of each movement. Pearson and Spearman correlation tests were applied.The results showed some correlation between morphology and muscle function (at a confidence level of 95 per cent). However, as the values of the correlation coefficient (r) were too low to establish associations between variables, it was concluded that the dimensions of the upper lip are not correlated with muscle activity.

Cytogenetic analyses of eight species in the genus Leptodactylus Fitzinger, 1843 (Amphibia, Anura, Leptodactylidae), including a new diploid number and a karyotype with multiple translocations

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of the riparian zone phytophysiognomies on the longitudinal distribution of fishes: evidence from a Brazilian savanna stream

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bayesian longitudinal data analysis with mixed models and thick-tailed distributions using MCMC

Linear mixed effects models are frequently used to analyse longitudinal data, due to their flexibility in modelling the covariance structure between and within observations. Further, it is easy to deal with unbalanced data, either with respect to the number of observations per subject or per time period, and with varying time intervals between observations. In most applications of mixed models to biological sciences, a normal distribution is assumed both for the random effects and for the residuals. This, however, makes inferences vulnerable to the presence of outliers. Here, linear mixed models employing thick-tailed distributions for robust inferences in longitudinal data analysis are described. Specific distributions discussed include the Student-t, the slash and the contaminated normal. A Bayesian framework is adopted, and the Gibbs sampler and the Metropolis-Hastings algorithms are used to carry out the posterior analyses. An example with data on orthodontic distance growth in children is discussed to illustrate the methodology. Analyses based on either the Student-t distribution or on the usual Gaussian assumption are contrasted. The thick-tailed distributions provide an appealing robust alternative to the Gaussian process for modelling distributions of the random effects and of residuals in linear mixed models, and the MCMC implementation allows the computations to be performed in a flexible manner.

Analyses of the modifications in the pi circuits for inclusion of frequency influence in transmission line representation

In this article, it is represented by state variables phase a transmission line which parameters are considered frequency independently and frequency dependent. It is analyzed what is the reasonable number of pi circuits and the number of blocks composed by parallel resistor and inductor in parallel for reduction of numerical oscillations. It is simulated the numerical routine with and without the effect of frequency in the longitudinal parameters. Initially, it is used state variables and pi circuits representing the transmission line composing a linear system which is solved by numerical routines based on the trapezoidal rule. The effect of frequency on the line is synthesized by resistors and inductors in parallel and this representation is analyzed in details. It is described transmission lines and the frequency influence in these lines through the state variables.

Wage differentials between the public and private sectors in Chile: Evidence from longitudinal data

Includes bibliography.