Neurocognitive effects of multivitamin supplementation on the steady state visually evoked potential (SSVEP) measure of brain activity in elderly women

OBJECTIVE: Growing evidence suggests that dietary supplementation with selected micronutrients and nutraceuticals may have the potential to improve cognition in older adults. Fewer studies have investigated the effects of these substances on brain activity. METHODS: This study was a randomised, double-blind, placebo-controlled trial, conducted to explore the effects of 16 weeks supplementation with a combined multivitamin, mineral and herbal formula on the steady state visually evoked potential (SSVEP) measure of brain electrical activity. Participants were elderly women aged between 64 and 79 years, with subjective memory complaints. Baseline and post-treatment SSVEP data was obtained for 22 participants in the multivitamin group and 19 in the placebo group. A spatial working memory delayed response task (DRT) was performed during the recording of the SSVEP. RESULTS: The results revealed that when compared to placebo, multivitamin supplementation delayed SSVEP latency during retrieval, interpreted as an increase in inhibitory neural processes. Behavioural performance on the DRT was not improved by the multivitamin, however improved performance accuracy was associated with increased midline central SSVEP latency. There were no multivitamin-related effects on SSVEP amplitude. CONCLUSION: These findings indicate that in the elderly, multivitamin supplementation may enhance neural efficiency during memory retrieval.

Validation of a trunk-mounted accelerometer to measure peak impacts during team sport movements

This study assessed the validity of an accelerometer to measure impacts in team sports. 76 participants completed a team sport circuit. Accelerations were collected concurrently at 100 Hz using an accelerometer and a 36-camera motion analysis system. The largest peak accelerations per movement were compared in 2 ways: i) pooled together and filtered at 13 different cut-off frequencies (range 6-25 Hz) to identify the optimal filtering frequency, and ii) the optimal cut-off frequency split into the 7 movements performed (n=532). Raw and 25-16 Hz filtering frequencies significantly overestimated and 6 Hz underestimated motion analysis peak accelerations (P <0.007). The 12 Hz filtered accelerometer data revealed the strongest relationship with motion analysis data (accuracy - 0.01±0.27 g, effect size - 0.01, agreement - 0.55 to 0.53 g, precision 0.27 g, and relative error 5.5%; P=1.00). The accelerometer underestimated peak accelerations during tackling and jumping, and overestimated during walking, jogging, sprinting and change of direction. Lower agreement and reduced precision were associated with sprinting, jumping and tackling. The accelerometer demonstrated an acceptable level of concurrent validity compared to a motion analysis system when filtered at a cut-off frequency of 12 Hz. The results advocate the use of accelerometers to measure movements in team sport.

Development of an instrument to measure self-efficacy in caregivers of people with advanced cancer

Objective : Informal caregivers of people with advanced cancer experience many negative impacts as a result of their role. There is a lack of suitable measures specifically designed to assess their experience. This study aimed to develop a new measure to assess self-efficacy in caregivers of people with advanced cancer.

Methods : The development and testing of the new measure consisted of four separate, sequential phases: generation of issues, development of issues into items, pilot testing and field testing. In the generation of issues, 17 caregivers were interviewed to generate data. These data were analysed to generate codes, which were then systematically developed into items to construct the instrument. The instrument was pilot tested with 14 health professionals and five caregivers. It was then administered to a large sample for field testing to establish the psychometric properties, with established measures including the Brief Cope and the Family Appraisals for Caregiving Questionnaire for Palliative Care.

Results : Ninety-four caregivers completed the questionnaire booklet to establish the factor structure, reliability and validity. The factor analysis resulted in a 21-item, four-factor instrument, with the subscales being termed Resilience, Self-Maintenance, Emotional Connectivity and Instrumental Caregiving. The test-retest reliability and internal consistency were both excellent, ranging from 0.73 to 0.85 and 0.81 to 0.94, respectively. Six convergent and divergent hypotheses were made, and five were supported.

Conclusions : This study has developed a new instrument to assess self-efficacy in caregivers of people with advanced cancer. The result is a four-factor, 21-item instrument with demonstrated reliability and validity.

The HWMD maturity model: a foundational framework to measure effectiveness of institutional research e-infrastructures

There is a nationally recognised need for a framework and tools to measure progress in implementing e-infrastructures for research from an institutional, organisational unit and service perspective. This paper describes the development of a prototype maturity model and self-assessment tool in response to that need. The authors present a background to the environment of technology enabling services for research and the challenges of fluidity of boundaries around traditional services and roles as institutions respond to the needs of the research community. The conceptual basis of the model is presented along with the model and its various elements that explain how the model is in its current form. The information provided in this paper, combined with field site test feedback, will promote discussion and debate amongst the community and opportunities will present to gather input to optimise the model. The next steps would be to further elaborate and test the constructs and indicators of the model in field test sites and to further develop the self -assessment tool.

Cancer Treatment Survey (CaTS): development and validation of a new instrument to measure patients' preparation for chemotherapy and radiotherapy

Objective: Cancer patients experience high levels of pre-treatment anxiety. Chemotherapy and radiotherapy are threatening medical procedures. Preparation for these procedures should include the provision of sensory and procedural information, and addressing fears. The aim of this study was to develop a cancer treatment survey (CaTS) to assess the preparation for chemotherapy and radiotherapy in cancer patients.

Methods: Drawing on evidence for how to prepare patients for threatening procedures, items were generated by psychosocial/clinical experts and pilot tested with cancer patients. The 36-item draft CaTS was administered to 192 cancer patients commencing chemotherapy for lymphoma, breast or colon cancer. Participants also completed the Hospital Anxiety and Depression Scale (HADS) and basic medical and demographic information was recorded.

Results: A systematic process of item selection removed 11 items. Factor analysis indicated a two-factor solution, with 11 items representing sensory/psychological concerns and 14 items representing procedural concerns. The two subscales demonstrated excellent internal reliability with Cronbach's alpha both over 0.90 and the average inter-item correlation for each scale exceeded 0.30. Divergent validity was established for both CaTS subscales with the HADS-A and-T (all r<0.30). Younger participants (under 65 years of age) had significantly greater procedural concerns (p = 0.001; medium effect).

Conclusions: The CaTS is a two factor, 25-item measure that assesses sensory/psychological concerns and procedural concerns relating to cancer treatment. The instrument provides a reliable and valid outcome measure for interventions to prepare cancer patients for chemotherapy and radiotherapy.

Functionalism, co-operation, good faith, and the making of the "daily-preventive justice" in contract law theory and practice. A contribution to a rational understanding of good faith and to its future reseasonable developments. Evaluations from

The thoughts and observations contained in this paper were first presented in a preliminary form at the Staff Seminar that I gave at the University of Cape Town (UCT) - Department of Private Law, on Tuesday May 8 2012. The organizers generously offered me a free choice of subject. Such an offer always poses a problem to imaginative people like myself. I finally chose as my subject the role of good faith in contract law theory and practice and then entitled the Seminar “Good Faith & Contracts - Brothers in Arms”. The aim of the talk was to briefly describe what I see behind the doctrine of good faith (and, more broadly, behind the general course of the parties’ behavior before and after the conclusion of an agreement), to then explain the need of its protection and future reasonable developments by challenging the limitations of both traditional and current legal approaches to contract law theory and practice. By adopting a comparative modus investigandi, it emerged that especially in the area of contract law a new law-finding process is emerging in the European continent and it is leading to re-conceive the meta-national legislative interventions by challenging the limits of Hobbes’s Leviathan. As asserted, we ought to not take this process for granted because although there are many forms of social organization, contract is the most pervasive and the law of contract still is the most important vehicle to support and supplement private arrangements. However, the point of departure for theorizing about private law is based on experience. Consequently, despite the growing emphasis on the convergence of national legal systems in Europe, conducting research on private law theory and practice requires that imagination and creativity be matched with prudence. Proficiency has to be aligned with what we have learned from history.

Fuzzy portfolio allocation models through a new risk measure and fuzzy sharpe ratio

A new portfolio risk measure that is the uncertainty of portfolio fuzzy return is introduced in this paper. Beyond the well-known Sharpe ratio (i.e., the reward-to-variability ratio) in modern portfolio theory, we initiate the so-called fuzzy Sharpe ratio in the fuzzy modeling context. In addition to the introduction of the new risk measure, we also put forward the reward-to-uncertainty ratio to assess the portfolio performance in fuzzy modeling. Corresponding to two approaches based on TM and TW fuzzy arithmetic, two portfolio optimization models are formulated in which the uncertainty of portfolio fuzzy returns is minimized, while the fuzzy Sharpe ratio is maximized. These models are solved by the fuzzy approach or by the genetic algorithm (GA). Solutions of the two proposed models are shown to be dominant in terms of portfolio return uncertainty compared with those of the conventional mean-variance optimization (MVO) model used prevalently in the financial literature. In terms of portfolio performance evaluated by the fuzzy Sharpe ratio and the reward-to-uncertainty ratio, the model using TW fuzzy arithmetic results in higher performance portfolios than those obtained by both the MVO and the fuzzy model, which employs TM fuzzy arithmetic. We also find that using the fuzzy approach for solving multiobjective problems appears to achieve more optimal solutions than using GA, although GA can offer a series of well-diversified portfolio solutions diagrammed in a Pareto frontier.

The development of a conceptual model and self-reported measure of occupational health and safety vulnerability

Injuries at work have a substantial economic and societal burden. Often groups of labour market participants, such as young workers, recent immigrants or temporary workers are labelled as being "vulnerable" to work injury. However, defining groups in this way does little to enable a better understanding of the broader factors that place workers at increased risk of injury. In this paper we describe the development of a new measure of occupational health and safety (OH&S) vulnerability. The purpose of this measure was to allow the identification of workers at increased risk of injury, and to enable the monitoring and surveillance of OH&S vulnerability in the labour market. The development included a systematic literature search, and conducting focus groups with a variety of stakeholder groups, to generate a pool of potential items, followed by a series of steps to reduce these items to a more manageable pool. The final measure is 29-item instrument that captures information on four related, but distinct dimensions, thought to be associated with increased risk of injury. These dimensions are: hazard exposure; occupational health and safety policies and procedures; OH&S awareness; and empowerment to participate in injury prevention. In a large sample of employees in Ontario and British Columbia the final measure displayed minimal missing responses, reasonably good distributions across response categories, and strong factorial validity. This new measure of OH&S vulnerability can identify workers who are at risk of injury and provide information on the dimensions of work that may increase this risk. This measurement could be undertaken at one point in time to compare vulnerability across groups, or be undertaken at multiple time points to examine changes in dimensions of OH&S vulnerability, for example, in response to a primary prevention intervention.

The influence of social disadvantage on children's emotional and behavioral difficulties at age 4-7 years

Objective To examine associations between indicators of social disadvantage and emotional and behavioral difficulties in children aged 4-7 years. Study design This cross-sectional study was based on data collected in a questionnaire completed by parents of children enrolled in their first year of school in Victoria, Australia, in 2010. Just over 57 000 children participated (86% of children enrolled), of whom complete data were available for 38 955 (68% of the dataset); these children formed the analysis sample. The outcome measure was emotional and behavioral difficulties, assessed by the Strengths and Difficulties Questionnaire Total Difficulties score. Logistic regression analyses were undertaken. Results Having a concession card (a government-issued card enabling access to subsidized goods and services, particularly in relation to medical care, primarily for economically vulnerable households) was the strongest predictor of emotional and behavioral difficulties (OR, 2.71; 95% CI, 2.39-3.07), followed by living with 1 parent and the parent's partner or not living with either parent (OR, 1.93; 95% CI, 1.58-2.37) and having a mother who did not complete high school (OR, 1.27; 95% CI, 1.11-1.45). Conclusion These findings may assist schools and early childhood practitioners in identifying young children who are at increased risk of emotional and behavioral difficulties, to provide these children, together with their parents and families, with support from appropriate preventive interventions.

Validity of a trunk-mounted accelerometer to measure physical collisions in contact sports

CONTEXT: Accelerometer peak impact accelerations are being used to measure player physical demands in contact sports. However, their accuracy to do so has not been ascertained. PURPOSE: To compare peak-impact-acceleration data from an accelerometer contained in a wearable tracking device with a 3-dimensional motion-analysis (MA) system during tackling and bumping. METHODS: Twenty-five semielite rugby athletes wore a tracking device containing a 100-Hz triaxial accelerometer (MinimaxX S4, Catapult Innovations, Australia). A single retroreflective marker was attached to the device, with its position recorded by a 12-camera MA system during 3 physical-collision tasks (tackle bag, bump pad, and tackle drill; N = 625). The accuracy, effect size, agreement, precision, and relative errors for each comparison were obtained as measures of accelerometer validity. RESULTS: Physical-collision peak impact accelerations recorded by the accelerometer overestimated (mean bias 0.60 g) those recorded by the MA system (P < .01). Filtering the raw data at a 20-Hz cutoff improved the accelerometer's relationship with MA data (mean bias 0.01 g; P > .05). When considering the data in 9 magnitude bands, the strongest relationship with the MA system was found in the 3.0-g or less band, and the precision of the accelerometer tended to reduce as the magnitude of impact acceleration increased. Of the 3 movements performed, the tackle-bag task displayed the greatest validity with MA. CONCLUSIONS: The findings indicate that the MinimaxX S4 accelerometer can accurately measure physical-collision peak impact accelerations when data are filtered at a 20-Hz cutoff frequency. As a result, accelerometers may be useful to measure physical collisions in contact sports.

The need to revise the current methods to measure and assess static recrystallization behavior

Heterogeneous deformation developed during "static recrystallization (SRX) tests" poses serious questions about the validity of the conventional methods to measure softening fraction. The challenges to measure SRX and verify a proposed kinetic model of SRX are discussed and a least square technique is utilized to quantify the error in a proposed SRX kinetic model. This technique relies on an existing computational-experimental multi-layer formulation to account for the heterogeneity during the post interruption hot torsion deformation. The kinetics of static recrystallization for a type 304 austenitic stainless steel deformed at 900 °C and strain rate of 0.01s^-1 is characterized implementing the formulation. Minimizing the error between the measured and calculated torque-twist data, the parameters of the kinetic model and the flow behavior during the second hit are evaluated and compared with those obtained based on a conventional technique. Typical static recrystallization distributions in the test sample will be presented. It has been found that the major differences between the conventional and the presented technique results are due to the heterogeneous recrystallization in the cylindrical core of the specimen where the material is still partially recrystallized at the onset of the second hit deformation. For the investigated experimental conditions, the core is confined in the first two-thirds of the gauge radius, when the holding time is shorter than 50 s and the maximum pre-strain is about 0.5.