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1H NMR relaxometry is used in earth science as a non-destructive and time-saving method to determine pore size distributions (PSD) in porous media with pore sizes ranging from nm to mm. This is a broader range than generally reported for results from X-ray computed tomography (X-ray CT) scanning, which is a slower method. For successful application of 1H NMR relaxometry in soil science, it is necessary to compare PSD results with those determined from conventional methods. The PSD of six disturbed soil samples with various textures and soil organic matter (SOM) content were determined by conventional soil water retention at matric potentials between −3 and −390 kPa (pF 1.5–3.6). These PSD were compared with those estimated from transverse relaxation time ( T2) distributions of water in soil samples at pF 1.5 using two different approaches. In the first, pore sizes were estimated using a mean surface relaxivity of each soil sample determined from the specific surface area. In the second and new approach, two surface relaxivities for each soil sample, determined from the T2 distributions of the soil samples at different matric potentials, were used. The T2 distributions of water in the samples changed with increasing soil matric potential and consisted of two peaks at pF 1.5 and one at pF 3.6. The shape of the T2 distributions at pF 1.5 was strongly affected by soil texture and SOM content ( R2 = 0.51 − 0.95). The second approach ( R2 = 0.98) resulted in good consistency between PSD, determined by soil water retention, and 1H NMR relaxometry, whereas the first approach resulted in poor consistency. Pore sizes calculated from the NMR data ranged from 100 μm to 10 nm. Therefore, the new approach allows 1H NMR relaxometry to be applied for the determination of PSD in soil samples and for studying swelling of SOM and clay and its effects on pore size in a fast and non-destructive way. This is not, or only partly, possible by conventional soil water retention or X-ray CT. [ABSTRACT FROM AUTHOR]

Whereas much research has explored the causes and consequences of the gender wage gap, far less has examined earnings differentials within marriage. This article contributes to this literature by utilizing the 2000 wave of the 1979 National Longitudinal Survey of Youth to examine variation in husbands' and wives' relative income by race/ethnicity, human capital, labor supply, and life stage. The author finds that Black women's disproportionate concentration among high relative earning wives can be attributed more to their greater attachment to paid labor than to their husbands' labor supply. Nonetheless, Black women's odds of earning as much as or more than their husbands are greater than those of White women. In addition, unlike research on the motherhood wage gap more generally, the author finds that the impact of motherhood on women's earnings relative to their husbands can be largely explained by mothers' lower labor supply relative to their childless counterparts. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We investigate the role of lithographically-induced strain relaxation in a micron-scaled device fabricated from epitaxial thin films of the magnetostrictive alloy Fe81Ga19. The strain relaxation due to lithographic patterning induces a magnetic anisotropy that competes with the magnetocrystalline and shape induced anisotropies to play a crucial role in stabilising a flux-closing domain pattern. We use magnetic imaging, micromagnetic calculations and linear elastic modelling to investigate a region close to the edges of an etched structure. This highly-strained edge region has a significant influence on the magnetic domain configuration due to an induced magnetic anisotropy resulting from the inverse magnetostriction effect. We investigate the competition between the strain-induced and shape-induced anisotropy energies, and the resultant stable domain configurations, as the width of the bar is reduced to the nanoscale range. Understanding this behaviour will be important when designing hybrid magneto-electric spintronic devices based on highly magnetostrictive materials. [ABSTRACT FROM AUTHOR]

Abstract Background Patient encounters are the core learning activity of Australian general practice (family practice) training. Exposure to patient demographics and presentations may vary from one general practice registrar (vocational trainee) to another. This can affect comprehensiveness of training. Currently, there is no mechanism to systematically capture the content of GP registrar consultations. The aim of the Registrar Clinical Encounters in Training (ReCEnT) study is to document longitudinally the nature and associations of consultation-based clinical and educational experiences of general practice registrars. Methods/design This is an ongoing prospective multi-site cohort study of general practice registrars’ consultations, entailing paper-based recording of consultation data. The study setting is general practices affiliated with three geographically-based Australian general practice regional training providers. Registrars record details of 60 consecutive consultations. Data collected includes registrar demographics, details of the consultation, patient demographics, reasons for encounter and problems managed. Problems managed are coded with the International Classification of Primary Care (second edition) classification system. Additionally, registrars record educational factors related to the encounter. The study will follow the clinical exposure of each registrar six-monthly over the 18 months to two years (full-time equivalent) of their general practice training program. Conclusions The study will provide data on a range of factors (patient, registrar and consultation factors). This data will be used to inform a range of educational decisions as well as being used to answer educational research questions. We plan to use ReCEnT as a formative assessment tool for registrars and help identify and address educational needs. The study will facilitate program evaluation by the participating training providers and thus improve articulation of educational programs with practice experience. From the research point of view it will address an evidence gap – the in-practice clinical and educational experience of general practice trainees, determinants of these experiences, and the determinants of registrars’ patterns of practice (for example, prescribing practice) over the course of their training.

Abstract Background What study participants think about the nature of a study has been hypothesised to affect subsequent behaviour and to potentially bias study findings. In this trial we examine the impact of awareness of study design and allocation on participant drinking behaviour. Methods/Design A three-arm parallel group randomised controlled trial design will be used. All recruitment, screening, randomisation, and follow-up will be conducted on-line among university students. Participants who indicate a hazardous level of alcohol consumption will be randomly assigned to one of three groups. Group A will be informed their drinking will be assessed at baseline and again in one month (as in a cohort study design). Group B will be told the study is an intervention trial and they are in the control group. Group C will be told the study is an intervention trial and they are in the intervention group. All will receive exactly the same brief educational material to read. After one month, alcohol intake for the past 4 weeks will be assessed. Discussion The experimental manipulations address subtle and previously unexplored ways in which participant behaviour may be unwittingly influenced by standard practice in trials. Given the necessity of relying on self-reported outcome, it will not be possible to distinguish true behaviour change from reporting artefact. This does not matter in the present study, as any effects of awareness of study design or allocation involve bias that is not well understood. There has been little research on awareness effects, and our outcomes will provide an indication of the possible value of further studies of this type and inform hypothesis generation. Trial Registration Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610000846022

Abstract Background Hazardous alcohol consumption is a leading modifiable cause of mortality and morbidity among young people. Screening and brief intervention (SBI) is a key strategy to reduce alcohol-related harm in the community, and web-based approaches (e-SBI) have advantages over practitioner-delivered approaches, being cheaper, more acceptable, administrable remotely and infinitely scalable. An efficacy trial in a university population showed a 10-minute intervention could reduce drinking by 11% for 6 months or more among 17-24 year-old undergraduate hazardous drinkers. The e-SBINZ study is designed to examine the effectiveness of e-SBI across a range of universities and among Māori and non-Māori students in New Zealand. Methods/Design The e-SBINZ study comprises two parallel, double blind, multi-site, individually randomised controlled trials. This paper outlines the background and design of the trial, which is recruiting 17-24 year-old students from seven of New Zealand's eight universities. Māori and non-Māori students are being sampled separately and are invited by e-mail to complete a web questionnaire including the AUDIT-C. Those who score >4 will be randomly allocated to no further contact until follow-up (control) or to assessment and personalised feedback (intervention) via computer. Follow-up assessment will occur 5 months later in second semester. Recruitment, consent, randomisation, intervention and follow-up are all online. Primary outcomes are (i) total alcohol consumption, (ii) frequency of drinking, (iii) amount consumed per typical drinking occasion, (iv) the proportions exceeding medical guidelines for acute and chronic harm, and (v) scores on an academic problems scale. Discussion The trial will provide information on the effectiveness of e-SBI in reducing hazardous alcohol consumption across diverse university student populations with separate effect estimates for Māori and non-Māori students. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12610000279022