Repeatability and validity of a food frequency questionnaire in free-living older people in relation to cognitive function

Objectives: To determine the repeatability and validity of a self-administered, 175-item food frequency questionnaire (FFQ) in free-living older people and to assess whether these are influenced by cognitive function. Participants and setting: 189 free-living people aged 64-80y were recruited from participants in a previous study. Design: To assess repeatability, 102 (52M, 50F) participants completed the FFQ on two occasions three months apart. To assess validity, another 87 participants (44 M, 43 F) completed the FFQ and a four-day weighed diet record three months later. 25 nutrients were studied. Results: For repeatability, Spearman rank correlation coefficients were above 0.35 (p<0.05) for all nutrients. Cohen’s weighted Kappa was above 0.4 for all nutrients except starch, riboflavin, retinol, β-carotene, and calcium. There were no substantial differences in correlation coefficients between sub-groups divided by short-term memory test score. There was no clear pattern for correlation coefficients in sub-groups divided by executive function test score. For validity, the Spearman rank correlation coefficients were above 0.2 (p<0.05) for all nutrients except fat, mono-unsaturated fatty acids, niacin equivalents and vitamin D, and Cohen’s weighted kappa was above 0.4 for alcohol and was above 0.2 for 13 other nutrients. Participants in the lowest-score groups of short-term memory and executive function had the lowest median Spearman correlation coefficient. Conclusions: The FFQ had reasonable repeatability and validity in ranking nutrient intakes in this population though the results varied between nutrients. Poor short-term memory or executive function may affect FFQ validity in ranking nutrient intakes

Testing stochastic software using Pseudo-oracles

Stochastic models can be difficult to test due to their complexity and randomness, yet their predictions are often used to make important decisions, so they need to be correct. We introduce a new search-based technique for testing implementations of stochastic models by maximising the differences between the implementation and a pseudo-oracle. Our technique reduces testing effort and enables discrepancies to be found that might otherwise be overlooked. We show the technique can identify differences challenging for humans to observe, and use it to help a new user understand implementation differences in a real model of a citrus disease (Huanglongbing) used to inform policy and research.Wellcome TrustThis is the author accepted manuscript. The final version is available from the Association for Computing Machinery via http://dx.doi.org/10.1145/2931037.293106

Formulas and Asymptotics for the Asymmetric Simple Exclusion Process

This is an expanded version of a series of lectures delivered by the second author in June, 2009. It describes the results of three of the authors' papers on ASEP, from the derivation of exact formulas for configuration probabilities, through Fredholm determinant representation, to asymptotics for ASEP with step initial condition establishing KPZ universality. Although complete proofs are in general not given, at least the main elements of them are.Comment: 25 pages. Version 2 corrects an error in Section II.

Assessing the relative validity of the Scottish Collaborative Group FFQ for measuring dietary intake in adults

Acknowledgements: The authors would like to thank Jacqueline Burr and Lindsey Shaw for collecting the data for this study. Data coding and entry for the food diaries was completed by Dr Lindsey Masson. The authors would also like to acknowledge the Scottish Health Survey Team, the Scottish Government and the National Centre for Social Research for their support in conducting this research. Financial support: This work was supported by funding from the Rural and Environment Science and Analytical Services Division (RESAS) programme of the Scottish Government (J.L.H., L.C.A.C., S.W. and G.Mc.N.). The RESAS programme had no role in the design, analysis or writing of this article. Conflict of interest: None. Authorship: J.L.H., L.C.A.C., S.W. and G.Mc.N. were responsible for the design of the study and formulated the research question. L.C.A.C. and S.W. carried out the study. J.L.H. completed the literature review, conducted the statistical analysis and drafted the initial paper. All authors were responsible for drafting and revising the manuscript and have approved the final version. Ethics of human subject participation: This study was conducted according to the guidelines laid down in the Declaration of Helsinki and all procedures involving human subjects were approved by the Rowett Human Studies Ethical Review Panel. Written informed consent was obtained from all participants.Peer reviewedPostprintPostprintPostprintPostprintPostprintPostprintPostprintPostprin

Directional emission of light from a nano-optical Yagi-Uda antenna

The plasmon resonance of metal nanoparticles can enhance and direct light from optical emitters in much the same way that radio frequency (RF) antennas enhance and direct the emission from electrical circuits. In the RF regime, a typical antenna design for high directivity is the Yagi-Uda antenna, which basically consists of a one-dimensional array of antenna elements driven by a single feed element. Here, we present the experimental demonstration of directional light emission from a nano-optical Yagi-Uda antenna composed of an array of appropriately tuned gold nanorods. Our results indicate that nano-optical antenna arrays are a simple but efficient tool for the spatial control of light emission.Comment: 4 pages, including 4 figure

Driving in stroke survivors aged 18–65 years: The Psychosocial Outcomes In StrokE (POISE) Cohort Study

Background: There is limited information regarding return to driving after stroke. Aims: To determine the frequency and predictors of return to driving within 1 month of acute stroke in younger (age 18–65 years) adults. Methods: POISE (Psychosocial Outcomes In StrokE) was a cohort study conducted in Australia between October 2008 and June 2010. Consecutive patients (age 18–65 years) with a recent (≤28 days) acute stroke were recruited. Validated demographic, clinical, mental health, cognitive, and disability measures including return to driving were obtained. Multivariable logistic regression was used to determine factors associated with return to driving within 1 month of stroke. Results: Among 359 participants who were legally able to drive before stroke, 96 (26.7%) returned to driving within 1 month. Compared to those without an early return to driving (n = 263), drivers were more often male, the main income earner, in paid work before stroke and without symptoms of depression or fatigue. Independence in activities of daily living (odds ratio (OR) 30.05, 95% confidence interval (CI) 3.85–234.45), not recalling receiving advice on driving cessation (OR 5.55, 95% CI 2.86–11.11), and having returned to paid work (OR 3.93, 95% CI 1.94–7.96) were associated with early return to driving. Conclusions: One in four young adults resumed driving within a month, contrary to guideline recommendations. These data reinforce the importance of deciding who is responsible for determining fitness to drive after stroke, when, and whether it is reasonable to enforce driving restrictions on those with minimal disability who are fit to return to work. Registration: Australian New Zealand Clinical Trials Registry ANZCTRN 12608000459325

HIRDLS poster

A poster supporting the HIRDLS data held at the BADC (High Resolution Dynamics Limb Sounder (HIRDLS) instrument)

Non-response bias in physical activity trend estimates

© 2009 Craig et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Evaluation of the effectiveness of a novel brain-computer interface neuromodulative intervention to relieve neuropathic pain following spinal cord injury: Protocol for a single-case experimental design with multiple baselines

Background: Neuropathic pain is a debilitating secondary condition for many individuals with spinal cord injury. Spinal cord injury neuropathic pain often is poorly responsive to existing pharmacological and nonpharmacological treatments. A growing body of evidence supports the potential for brain-computer interface systems to reduce spinal cord injury neuropathic pain via electroencephalographic neurofeedback. However, further studies are needed to provide more definitive evidence regarding the effectiveness of this intervention. Objective: The primary objective of this study is to evaluate the effectiveness of a multiday course of a brain-computer interface neuromodulative intervention in a gaming environment to provide pain relief for individuals with neuropathic pain following spinal cord injury. Methods: We have developed a novel brain-computer interface-based neuromodulative intervention for spinal cord injury neuropathic pain. Our brain-computer interface neuromodulative treatment includes an interactive gaming interface, and a neuromodulation protocol targeted to suppress theta (4-8 Hz) and high beta (20-30 Hz) frequency powers, and enhance alpha (9-12 Hz) power. We will use a single-case experimental design with multiple baselines to examine the effectiveness of our self-developed brain-computer interface neuromodulative intervention for the treatment of spinal cord injury neuropathic pain. We will recruit 3 participants with spinal cord injury neuropathic pain. Each participant will be randomly allocated to a different baseline phase (ie, 7, 10, or 14 days), which will then be followed by 20 sessions of a 30-minute brain-computer interface neuromodulative intervention over a 4-week period. The visual analog scale assessing average pain intensity will serve as the primary outcome measure. We will also assess pain interference as a secondary outcome domain. Generalization measures will assess quality of life, sleep quality, and anxiety and depressive symptoms, as well as resting-state electroencephalography and thalamic γ-aminobutyric acid concentration. Results: This study was approved by the Human Research Committees of the University of New South Wales in July 2019 and the University of Technology Sydney in January 2020. We plan to begin the trial in October 2020 and expect to publish the results by the end of 2021. Conclusions: This clinical trial using single-case experimental design methodology has been designed to evaluate the effectiveness of a novel brain-computer interface neuromodulative treatment for people with neuropathic pain after spinal cord injury. Single-case experimental designs are considered a viable alternative approach to randomized clinical trials to identify evidence-based practices in the field of technology-based health interventions when recruitment of large samples is not feasible