Age-dependence of the average and equivalent refractive indices of the crystalline lens

Lens average and equivalent refractive indices are required for purposes such as lens thickness estimation and optical modeling. We modeled the refractive index gradient as a power function of the normalized distance from lens center. Average index along the lens axis was estimated by integration. Equivalent index was estimated by raytracing through a model eye to establish ocular refraction, and then backward raytracing to determine the constant refractive index yielding the same refraction. Assuming center and edge indices remained constant with age, at 1.415 and 1.37 respectively, average axial refractive index increased (1.408 to 1.411) and equivalent index decreased (1.425 to 1.420) with age increase from 20 to 70 years. These values agree well with experimental estimates based on different techniques, although the latter show considerable scatter. The simple model of index gradient gives reasonable estimates of average and equivalent lens indices, although refinements in modeling and measurements are required.

Satiety responsiveness in toddlerhood predicts energy intake and weight status at four years of age

The aim of this study was to examine whether maternal-report of child eating behaviour at two years predicted self-regulation of energy intake and weight status at four years. Using an ‘eating in the absence of hunger’ paradigm, children’s energy intake (kJ) from a semi-standardized lunch meal and a standardized selection of snacks were measured. Participants were 37 mother-child dyads (16 boys, Median child age = 4.4 years, Inter-quartile range = 3.7-4.5 years) recruited from an existing longitudinal study (NOURISH randomised controlled trial). All participants were tested in their own home. Details of maternal characteristics, child eating behaviours (at age two years) reported by mothers on a validated questionnaire, and measured child height and weight (at age 3.5-4 years) were sourced from existing NOURISH trial data. Correlation and partial correlation analyses were used to examine longitudinal relationships. Satiety responsiveness and Slowness in eating were inversely associated with energy intake of the lunch meal (partial r = -.40, p =.023, and partial r = -.40, p = .023) and the former was also negatively associated with BMI-for-age Z score (partial r = -.42, p = .015). Food responsiveness and Enjoyment of food were not related to energy intake or BMI Z score. None of the eating behaviours were significantly associated with energy intake of the snacks (i.e., eating in the absence of hunger). The small and predominantly ‘healthy weight’ sample of children may have limited the ability to detect some hypothesized effects. Nevertheless, the study provides evidence for the predictive validity of two eating behaviours and future research with a larger and more diverse sample should be able to better evaluate the predictive validity of other children’s early eating behaviour styles.

Exploring the influences of country-level factors on mid-age women’s drink driving attitudes

Drink driving remains a major cause of serious and fatal car crashes in Australia and internationally. While this problem is more prevalent among male drivers, the rates of female intoxicated drivers have increased steadily over the past decades in many motorised countries. A combination of police enforcement, media awareness campaigns, and community initiatives has played a key role in reducing incidents of illegal drink driving by targeting public drink driving attitudes. However, important cultural differences in regards to the tolerance towards drink driving have been noted. While many countries, including Australia, have a legal Blood Alcohol Concentration (BAC) limit of .05 or higher, some countries have moved towards a zero –or low tolerance approach to drink driving; several European countries, including Sweden, Hungary, Slovakia, and Estonia currently enforce .00 or .02 BAC limits.

Association between maternal depressive symptoms in the early postnatal period and responsiveness in feeding at child age 2 years

Maternal depression is a known risk factor for poor outcomes for children. Pathways to these poor outcomes relate to reduced maternal responsiveness or sensitivity to the child. Impaired responsiveness potentially impacts the feeding relationship and thus may be a risk factor for inappropriate feeding practices. The aim of this study was to examine the longitudinal relationships between self-reported maternal post-natal depressive symptoms at child age 4 months and feeding practices at child age 2 years in a community sample. Participants were Australian first-time mothers allocated to the control group of the NOURISH randomized controlled trial when infants were 4 months old. Complete data from 211 mothers (of 346 allocated) followed up when their children were 2 years of age (51% girls) were available for analysis. The relationship between Edinburgh Postnatal Depression Scale (EPDS) score (child age 4 months) and child feeding practices (child age 2 years) was tested using hierarchical linear regression analysis adjusted for maternal and child characteristics. Higher EPDS score was associated with less responsive feeding practices at child age 2 years: greater pressure [β = 0.18, 95% confidence interval (CI): 0.04–0.32, P = 0.01], restriction (β = 0.14, 95% CI: 0.001–0.28, P = 0.05), instrumental (β = 0.14, 95% CI: 0.005–0.27, P = 0.04) and emotional (β = 0.15, 95% CI: 0.01–0.29, P = 0.03) feeding practices (ΔR2 values: 0.02–0.03, P < 0.05). This study provides evidence for the proposed link between maternal post-natal depressive symptoms and lower responsiveness in child feeding. These findings suggest that the provision of support to mothers experiencing some levels of depressive symptomatology in the early post-natal period may improve responsiveness in the child feeding relationship.

Stereotypes of age differences in personality traits : universal and accurate?

Age trajectories for personality traits are known to be similar across cultures. To address whether stereotypes of age groups reflect these age-related changes in personality, we asked participants in 26 countries (N = 3,323) to rate typical adolescents, adults, and old persons in their own country. Raters across nations tended to share similar beliefs about different age groups; adolescents were seen as impulsive, rebellious, undisciplined, preferring excitement and novelty, whereas old people were consistently considered lower on impulsivity, activity, antagonism, and Openness. These consensual age group stereotypes correlated strongly with published age differences on the five major dimensions of personality and most of 30 specific traits, using as criteria of accuracy both self-reports and observer ratings, different survey methodologies, and data from up to 50 nations. However, personal stereotypes were considerably less accurate, and consensual stereotypes tended to exaggerate differences across age groups.

Age-related trends in urinary excretion of bisphenol A in Australian children and adults : evidence from a pooled sample study using samples of convenience

Bisphenol A (BPA or 4,4’-(propane-2,2-diyl)diphenol) is a chemical intermediate in the production of polycarbonate and epoxy resins, and used in a wide range of applications. BPA has attracted significant attention in the past decade due to its frequency of detection in human populations worldwide, demonstrated animal toxicity and potential impact on human health, particularly during critical periods of development. The aim of this study was to perform a preliminary assessment of age-related trends in urinary concentration and to estimate daily excretion of BPA in Australian children (aged (>0 – <5 years) and adults (≥15 – <75 years). This was achieved using 79 samples pooled by age and gender, created from 868 individual samples of convenience collected as part of routine, community-based pathology testing. Total BPA was analyzed using online-SPE-LC-MS/MS and detected in all samples with a range of 0.65 – 265 ng/ml. No significant differences were observed between males and females. A urine flow model was constructed from published values and used to provide an estimate of daily excretion per unit bodyweight for each pooled sample. The daily excretion estimates ranged from 26.2 – 18200 ng/kg-d for children; and 20.1 – 165 ng/kg-d for adults. Urinary concentrations and estimated excretion rates were inversely associated with age, and estimated daily excretion rates in infants and young children were significantly higher than in adults (geometric mean: 107 and 47.0 ng/kg-d, respectively). Higher excretion of BPA in children may be explained by their higher food consumption relative to body weight compared to adults and adolescents, and may also reflect alternative exposure pathways and sources. Keywords: bisphenol A, biomonitoring, children, urine flow, Australia

Harm, responsibility, age and consent

This article explores the contradictory ways in which adolescents just under the age of consent are represented in illegal sexual relations with both men and women who are over the age of consent. We are specifically interested in the ways in which the gender of the adolescent and the adult affect public perceptions, legal responses and perceptions of harm of sexual relations. We argue that the development of an indiscriminate legal and policy narrative of child abuse which increasingly includes all aspects of adolescent sexuality, ‘erases’ adolescent subjectivity. By exploring the nuanced ways in which the historical construction of childhood as sexually innocent intersects with current cultural scripts of femininity and masculinity, this article hopes to add to the small but growing literature on the issue of sexual consent, sexual ethics and sexual citizenship for young people.

The future of the music industry in an age of digital distribution

This is an invited public lecture. The talk will cover how the music industry has changed due to digital technologies. During the talk I will look at how the changing balance between live music, music licensing and recorded music. I will also discuss online music subscription services and whether they might be a future for music distribution in China and elsewhere in the world. It will also look at how music artists and composers are affected by this change.

Exposure to solar ultraviolet radiation is associated with a decreased folate status in women of childbearing age

In vitro studies indicate that folate in collected human blood is vulnerable to degradation after exposure to ultraviolet (UV) radiation. This has raised concerns about folate depletion in individuals with high sun exposure. Here, we investigate the association between personal solar UV radiation exposure and serum folate concentration, using a three-week prospective study that was undertaken in females aged 18–47 years in Brisbane, Australia (153 E, 27 S). Following two weeks of supplementation with 500 μg of folic acid daily, the change in serum folate status was assessed over a 7-day period of measured personal sun exposure. Compared to participants with personal UV exposures of <200 Joules per day, participants with personal UV exposures of 200–599 and >600 Joules per day had significantly higher depletion of serum folate (p = 0.015). Multivariable analysis revealed personal UV exposure as the strongest predictor accounting for 20% of the overall change in serum folate (Standardised B = −0.49; t = −3.75; p = <0.01). These data show that increasing solar UV radiation exposures reduces the effectiveness of folic acid supplementation. The consequences of this association may be most pronounced for vulnerable individuals, such as women who are pregnant or of childbearing age with high sun exposures.

Boken, berättelsen, pengarna I den digitala tidsåldern [The book, the story and the money in the digital age]

År 2012 är distribution av litteratur via internet inte längre en framtidsvision, utan ett etablerat format vid sidan av traditionella format som exempelvis pocketboken, den inbundna boken och ljudboken (AAP 2011; Amazon 2011; PaidContent 2011). Men den digitala tekniken etablerar inte enbart ett nytt format, utan förändrar också grundförutsättningarna för litterära konstformer och marknader. Detta kapitel behandlar en betydelsefull aspekt av denna förändring, nämligen hur den digitala tekniken påverkar relationen mellan läsare och författare och ökar läsarens inflytande över den kreativa processen. I den digitala tidsåldern är det möjligt att skapa berättelser online i en interaktiv process som involverar både läsare och författare. Kapitlet presenterar modeller för hur sådan “samproducerad e-litteratur” förändrar marknaden för litteratur och hur den påverkar den traditionella litteraturen.

Co-morbidity of depression and anxiety in common age-related eye diseases : a population-based study of 662 adults

This study examined the prevalence of co-morbid age-related eye disease and symptoms of depression and anxiety in late life, and the relative roles of visual function and disease in explaining symptoms of depression and anxiety. A community-based sample of 662 individuals aged over 70 years was recruited through the electoral roll. Vision was measured using a battery of tests including high and low contrast visual acuity, contrast sensitivity, motion sensitivity, stereoacuity, Useful Field of View, and visual fields. Depression and anxiety symptoms were measured using the Goldberg scales. The prevalence of self-reported eye disease [cataract, glaucoma, or age-related macular degeneration (AMD)] in the sample was 43.4%, with 7.7% reporting more than one form of ocular pathology. Of those with no eye disease, 3.7% had clinically significant depressive symptoms. This rate was 6.7% among cataract patients, 4.3% among those with glaucoma, and 10.5% for AMD. Generalized linear models adjusting for demographics, general health, treatment, and disability examined self-reported eye disease and visual function as correlates of depression and anxiety. Depressive symptoms were associated with cataract only, AMD, comorbid eye diseases and reduced low contrast visual acuity. Anxiety was significantly associated with self-reported cataract, and reduced low contrast visual acuity, motion sensitivity and contrast sensitivity. We found no evidence for elevated rates of depressive or anxiety symptoms associated with self-reported glaucoma. The results support previous findings of high rates of depression and anxiety in cataract and AMD, and in addition show that mood and anxiety are associated with objective measures of visual function independently of self-reported eye disease. The findings have implications for the assessment and treatment of mental health in the context of late-life visual impairment...

Exploring differences in driving behaviour across age and years of education of taxi drivers in Addis Ababa, Ethiopia

Despite statistics indicating that the African region has the highest road traffic fatality rate globally, there is limited scientific literature identifying the determinants of driving behaviour. In this study, we explore differences in self-reported driving behaviour across age groups and years of education in a population of 213 drivers from Addis Ababa, Ethiopia. We hypothesize that younger, less educated drivers will report engaging in more unsafe driving behaviours compared to older, more educated drivers. Contrary to expectations, we found the opposite effect, whereby older, more educated drivers reported engaging in more unsafe driving behaviours than younger, less educated drivers. We explain these findings by describing key characteristics of the sample and cultural ideologies of the region. The findings of this study offer some practical guidance for intervention to address the burden of road traffic injury and death in the African region.

The tertiary debate : a case study analysis of factors considered when applying for university entry by traditional age school leavers in Brisbane

Many interacting factors contribute to a student's choice of a university. This study takes a systems perspective of the choice and develops a Bayesian Network to represent and quantify these factors and their interactions. The systems model is illustrated through a small study of traditional school leavers in Australia, and highlights similarities and differences between universities' perceptions of student choices, students' perceptions of factors that they should consider and how students really make choices. The study shows the range of information that can be gained from this approach, including identification of important factors and scenario assessment.