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BackgroundExposure to adversity during childhood is estimated to at least double the risk of depression later in life. Some evidence suggests childhood adversity may have a greater impact on depression risk, if experienced during specific windows of development called sensitive periods. During these sensitive periods, there is evidence that adversity may leave behind biological memories, including changes in DNA methylation (DNAm). Here we ask if those changes play a role in the link between adversity and later adolescent depressive symptoms.MethodsWe applied a method for high-dimensional mediation analysis using data from a subsample (n=627-675) of the Avon Longitudinal Study of Parents and Children. We first assessed the possibility of time-dependent relationships between seven types of childhood adversity (caregiver abuse, physical/sexual abuse, maternal psychopathology, one-adult household, family instability, financial stress, neighborhood disadvantage), measured on at least four occasions between ages 0-7 years, and adolescent depression at mean age 10.6. Specifically, we considered three types of life course hypotheses (sensitive periods, accumulation, and recency), and then evaluated which of these hypotheses had the strongest association in each adversity-adolescent depression relationship using the structured life course modeling approach (SLCMA; pronounced “slick-mah”). To conduct the mediation analyses, we used a combination of pruning and sure independence screening (a dimension reduction method) to reduce the number of methylated CpG sites under consideration to a viable subset for our sample size. We then applied a sparse group lasso penalized model to identify the top mediating loci from that subset using the combined strength of the coefficient measuring the relationship between the childhood adversity and a CpG site (α) and of the coefficient measuring the relationship between the CpG site and depressive symptoms (β) as a metric. Using a Monte Carlo method for assessing mediation (MCMAM), we assigned a significance level and confidence interval to each identified mediator.ResultsAcross all seven adversities, we identified a total of 70 CpG sites that showed evidence of mediating the relationship between adversity and adolescent depression symptoms. Of these 70 mediators, 37 were significant at the p < 0.05 level when applying the MCMAM, a method tailored to estimating the significance of SEM-derived mediation effects. These sites exhibited four different mediating patterns, differentiated by the direction of α and β. These patterns had signals that were: (1) both positive (19 loci), (2) both negative (18 loci), (3) positive α and negative β (23 loci) or (4) negative α and positive β (10 loci).ConclusionOur results suggest that DNAm partially mediates the relationship between different types of childhood adversity and depressive symptoms in adolescence. These findings provide insight into the biological mechanisms that link childhood adversity to depression, which will ultimately help develop treatments to prevent depression in more vulnerable populations.

BackgroundChildren exposed to adversity often have epigenetic profiles, including DNA methylation (DNAm) signatures, that differ from children without adversity histories. These signatures may be more common among children exposed during sensitive periods in development. However, it remains unclear if adversity has persistent (versus transient) effects on the epigenome across childhood and adolescence. Thus, we examined the relationship between time-varying adversity and genome-wide DNAm, measured three times from birth to adolescence using prospective data from the Avon Longitudinal Study of Parents and Children.MethodsWe first investigated the timing of exposure to seven types of adversity (measured 5-8 times between ages 0-11) and DNAm at age 15 using a structured life course modeling approach (SLCMA). We also assessed the persistence of adversity-DNAm associations identified from age 7 DNAm into adolescence and the influence of adversity on DNAm trajectories from ages 0-15.ResultsAdversity exposure was associated with differences in age 15 DNAm at 41 loci (R2≥0.035; p−5; 22 at FDRConclusionsThese findings highlight the immediate and latent effects of childhood adversity on DNAm, providing a potential biological mechanism linking adversity to physical and mental health outcomes across development.

Childhood socioeconomic position (SEP) is a major determinant of health and well-being across the entire life course. To effectively prevent and reduce health risks related to SEP, it is critical to better understand when and under what circumstances socioeconomic adversity shapes biological processes. DNA methylation (DNAm) is one such mechanism for how early life adversity “gets under the skin”. Using data from a large, longitudinal birth cohort, we showed that changes in the socioeconomic environment may influence DNAm at age 7. We also showed that middle childhood (ages 6-7) may be a potential sensitive period when socioeconomic instability, reflected in parental job loss, is especially important in shaping DNAm. Our findings highlight the importance of socioeconomic stability during childhood, providing biological evidence in support of public programs to help children and families experiencing socioeconomic instability and other forms of socioeconomic adversity during childhood.

IntroductionBiomedical research has grown increasingly cooperative, with several large consortia compiling and sharing epigenomic data. Since data are typically preprocessed by consortia prior to distribution, the implementation of new pipelines can lead to different versions of the same dataset. Analytic frameworks also constantly evolve to incorporate cutting-edge methods and shifting best practices. However, it remains unknown how differences in data and analytic versions alter the results of epigenome-wide analyses, which has broad implications for the replicability of epigenetic associations. Thus, we assessed the impact of these changes using a subsample of the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort.MethodsWe analyzed two versions of DNA methylation data, processed using separate preprocessing and analytic pipelines, to examine associations between childhood adversity and prenatal smoking exposure on DNA methylation at age 7. We performed two sets of analyses: (1) epigenome-wide association studies (EWAS); (2) Structured Life Course Modeling Approach (SLCMA), a two-stage method that models time-dependent effects. We also compared results from the SLCMA using more recent methodological recommendations.ResultsDifferences between ALSPAC data versions impacted both EWAS and SLCMA analyses, yielding different sets of associations at conventional p-value thresholds. However, the magnitude and direction of associations was generally consistent between data versions, regardless of significance thresholds. Updating the SLCMA analytic version similarly altered top associations, but time-dependent effects remained concordant.ConclusionsChanges to data and analytic versions influenced the results of epigenome-wide studies, particularly when using p-value thresholds as reference points for successful replication and stability.

©, Copyright © Taylor & Francis Group, LLC. The popular reality television show The Biggest Loser Australia (TBL) is a significant source of media content about physical activity. This study examined audience responses to and interpretations of physical activity in TBL. A qualitative study using in-depth interviews was conducted in New South Wales, Australia. A sample of 46 viewers of TBL was recruited, stratified by gender, age group, area of residence, and body mass index. Interview data were thematically analyzed to identify how viewers evaluated TBL. Respondents were most positive about TBL as public health education, premised on personal responsibility, the need for extreme action, and the possibilities of human agency (individually and collectively). Conversely, they were critical about whether the portrayal of physical activity could guide and inspire them personally. They expressed feelings of disgust and fear in response to the exercise challenges, questioned the practicality of the behavior change process in light of their own experience, and were skeptical about the purpose of the program itself. TBL’s representation of physical activity may be limited in its capacity to encourage physical activity. Despite the wide viewership of this program, encouraging physical requires innovation in the development of practical, persuasive and evidence based media messages about physical activity.

Solar energetic particles (SEPs) endanger satellites, disrupt air traffic over the polar regions and high frequency radio communication.The capacity to predict SEP events on Earth ahead of time can lead to the preservation of important space and aeronautical assets as well as well as protection for humans in space. Considering that the methods of acceleration and transport of these particles is still an area of active research and that physics-based models are, at the moment, slower than empirical models, forecasters at the National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center (SWPC) use the latter, combined with forecaster heuristics, to make real time decisions. This project attempts to improve upon the results of the current statistical model in use at SWPC (Proton Prediction Model) by using machine learning classification techniques. Machine learning models learn and make decisions using an observational training set and are currently much quicker than numerical models for issuing a forecast. SEP forecasts are made based on physical parameters associated with solar flares and coronal mass ejections. Preliminary results show that the logistic regression, Adaboost decision tree, and support vector machine algorithms show an improvement in forecasting skill over the current SWPC Proton Prediction Model.

© the Owner Societies 2016. Bioinspired fibres and hierarchical nano-materials are based on the self-assembly of organic building blocks such as polypeptides. Confirming the core structure of such materials is often challenging as they lack the long-range order required by crystallographic methods. Far-IR spectroscopy characterizes the vibrational modes of large molecular units. These vibrational modes are very sensitive to angle strain and second order interactions such as hydrogen bonding. As such, far-IR spectra hold information about the secondary structure and interactions of large biomolecules. Here we analyze the far-IR vibrational spectra of fibrous nano-materials based on three isomeric unnatural tripeptides, Ac-β3Leu-β3Ile-β3Ala, Ac-β3Ile-β3Ala-β3Leu, and Ac-β3Ala-β3Leu-β3Ile. These peptides have well described self-assembly characteristics, forming one-dimensional nanorods that impose tight conformational constraints on the constituent molecules. The synchrotron far-IR spectroscopic results were interpreted by using density functional theory (DFT) modelling based vibrational analysis. The sensitivity of the spectra to peptide conformation was assessed by comparing the experimental spectra with DFT predictions. In high dielectric implicit solvent, intramolecular hydrogen-bonding is inhibited and thus the energy minimized peptide structure remains close to the 14-helix folding characteristic of substituted β3-peptides, giving good agreement between the experimental and predicted vibration spectra. In contrast, energy minimization in vacuum alters the peptide conformation leading to intramolecular hydrogen bonds, and hence the predicted vibration spectra do not agree with the experimental data. Therefore, our results demonstrate the ability of far-IR spectroscopy to identify correct structural predictions and thus open the way for using far-IR spectroscopy for the characterization and structural analysis of bioinspired nano-materials and potentially their interactions with surfaces, ionic environments and other biomolecules. Far-IR structural analysis is particularly powerful in case of one- and two-dimensional materials such as fibres, hydrogels and thin layers where standard crystallographic analysis is not available.

© 2015 The Author 2015. Published by Oxford University Press. All rights reserved. Physical activity's role in promoting health is highlighted in public health campaigns, news and current affairs, reality television and other programs. An investigation of audience exposure, beliefs and reactions to media portrayals of physical activity offers insights into the salience and influence of this communication. An audience reception study was conducted involving in-depth interviews with 46 adults in New South Wales, Australia. The sample was stratified by gender, age group, area of residence and body mass index. Most respondents could only recall media coverage of physical activity with prompting. Television was the primary channel of exposure, with reality television the dominant source, followed by news programs and sports coverage. The messages most readily recalled were the health risks of inactivity, especially obesity, and the necessity of keeping active. Physical activity was regarded as a matter of personal volition, or for children, parental responsibility. Respondents believed that the media had given physical activity inadequate attention, focused too heavily on risks and not provided practical advice. In Australia, there is a need to counter the framing of physical activity by reality television, and engage the media to generate understanding of the socioecological determinants of inactivity. Physical activity campaigns should deliver positive and practical messages.

Physical activity (PA) reduces the risk of chronic disease, but few studies have analysed how news reports PA. This research analyses how television news frames PA. Content and framing analysis was used to examine 91 television news and current affairs stories. Stories were coded for length, prominence, age groups, gender, responsibility, types of activity, barriers to PA, risks and benefits of physical activity and inactivity, and uses of expertise. Few stories focused on men (12 per cent) or women (13 per cent) and most focused on adults. Benefits outnumbered risks. Less than one-third of stories mentioned the risks of inactivity. Responsibility for overcoming barriers was often attributed to individuals. Few stories were broadcast prominently. News coverage of PA reinforces social beliefs about individual responsibility for healthy lifestyles and downplays the role of policy and the impact of the environment. Television coverage rarely gives physical activity the authority of hard news prominence, uses few academic sources and tends to neglect the risks of inactivity.

We present the first quantum tomography of a detector, using as examples an avalanche photodiode and a photon-number resolving detector. The resulting POVM set agrees well with one derived from a model of the detector. © 2008 Optical Society of America.

We demonstrate experimentally the realization of heralded pure photons generation in a birefringent optical fiber. © 2008 Optical Society of America.

We introduce a complete tomographic reconstruction scheme geared toward low photon-number states. To demonstrate this method we reconstruct various single-mode coherent states. © 2008 Optical Society of America.

We experimentally demonstrate a heralded source of high-purity two-photon NOON states derived from heralded single-photon sources. © 2008 Optical Society of America.

Substantial cross-sectional evidence and limited longitudinal research indicates that the availability of recreational facilities (e.g., parks, fitness centres) is associated with physical activity participation. However, few intervention trials have investigated how recreational infrastructure can be used to reduce inactivity levels in communities. The MOVE Frankston study aimed to assess the impact of low intensity strategies to promote use of a multi-purpose leisure and aquatic centre in a socioeconomically diverse, metropolitan community. This randomised controlled trial of two years’ duration compared public awareness raising (control condition) with two interventions: mailed information about the centre and a free entry pass (I-O); and this minimal intervention supplemented by customer relations management support through telephone contact, mailed promotional materials and additional incentives (I+S). Participants (n = 1320) were inactive adults living in the City of Frankston, Melbourne Australia. There were 928 people (70.3%) followed up at 12 months (61.2% female, 52% ≥55 yrs). Compared with controls, attendance at the Centre once or more was higher in both the I-O (OR 1.79, 95% CI 1.28–2.50) and I+S groups (OR 1.46, 95% CI 1.03–2.07). The proportion of people using the centre weekly did not differ by group. The odds of being in contemplation or preparation to use the Centre were higher in both the I-O (OR 1.76, 95% CI 1.28–2.42) and I+S groups (OR 1.48, 95% CI 1.07–2.06). Total physical activity and related social and cognitive factors did not differ between the groups. The findings show that the low intensity promotional strategies prompted occasional attendance and increased readiness to use this recreational facility, a level of behaviour change unlikely to reduce non-communicable disease risk. It is recommended that more frequent customer relations contact, and involvement of healthcare providers, be tested as strategies to encourage inactive adults to take up physical activity opportunities at recreational facilities of this type.

Summary A 1987 survey of 758 eighth-grade students from three rural counties in Maryland revealed that 61 percent of males and 47 percent of females have engaged in sexual intercourse, and that 77 percent of black students and 40 percent of whites have ever had intercourse. A logistic regression analyzing the effects of race and gender shows that the odds that young black teenagers would have had intercourse are over five times those for whites, and that the odds for males are about twice those for females. The introduction of developmental, individual, academic and behavioral factors into the regression model has little effect on these odds ratios. Separate logistic analyses of four subgroups-white males, white females, black males and black females-reveal no consistent associations between sexual activity and the factors examined. For example, such types of problem behavior as cigarette smoking and use of alcohol or certain other drugs are associated with the likelihood of sexual activity, but the specific type of behavior involved differs by subgroup: Cigarette smoking is related to an increased likelihood of sexual activity just among white females, while alcohol consumption is associated with sexual experience among black females and white males only. Use of drugs other than marijuana or alcohol is linked to a 5-9 times

The aim of this study was to evaluate a novel patient-held manual designed to reduce the evidence–practice gap in chronic obstructive pulmonary disease (COPD). The intervention manual contained summaries of research evidence. It was developed using current best practice for patient information materials and designed to cause discussion of evidence between patient and doctor. A controlled before-and-after study was employed in two similar but geographically separate regions of metropolitan Adelaide, South Australia. Participants had moderate to severe COPD, with 249 included at baseline and 201 completing the study. Evidence-based COPD management was measured using an indicator with three components: rates of influenza vaccination, bone density testing, and pulmonary rehabilitation. A survey of behavioral steps leading to practice change was conducted with the trial. Analysis, by median split of socioeconomic disadvantage, showed significant difference between study arms for only one component of the indicator of evidence-based practice, enrolment in pulmonary rehabilitation and only for the most socioeconomically disadvantaged stratum. For both socioeconomic strata, more intervention participants than control participants reported remembering being given the information material, reading part or all, and finding it very or quite helpful. Other significant differences were restricted to the stratum of greatest socioeconomic disadvantage: reading all of the material, learning from it, referring back, and talking to a doctor about a topic from the material. Above 90% of all participants who received the manual reported reading from it, 42% reported discussing topics with a doctor, but only 10% reported treatment change attributable to the manual. We have found that people with COPD will read an evidence manual developed using current best practice. However, the study demonstrated improvement for only one of the three components of an indicator of evidence-based disease management for only the most socioeconomically disadvantaged stratum of participants. Future interventions should be designed to better translate reading uptake into evidence-based disease management. Refereed/Peer-reviewed