Introgression of domesticated alleles into a wild trout genotype and the impact on seasonal survival in natural lakes

We tested the fitness consequences of introgression of fast-growing domesticated fish into a wild population. Fry from wild and domesticated rainbow trout (Oncorhynchus mykiss) crosses, F1 hybrids, and first- and second-generation backcrosses were released into two natural lakes. Parentage analysis using microsatellite loci facilitated the identification of survivors, so fitness was estimated in nature from the first-feeding stage. Results indicated that under certain conditions, domesticated fish survived at least as well as wild fish within the same environment. Relative growth and survival of the crosses, however, were highly dependent on environment. During the first summer, fastest-growing crosses had the highest survival, but this trend was reversed after one winter and another summer. Although the F1 hybrids showed evidence of outbreeding depression because of the disruption of local adaptation, there was little evidence of outbreeding depression in the backcrosses, and the second-generation backcrosses exhibited a wild-type phenotype. This information is relevant for assessing the multigenerational risk of escaped or released domesticated fish should they successfully interbreed with wild populations and provides information on how to minimize detrimental impacts of a conservation breeding and/or management programme. These data also further understanding of the selection pressures in nature that maintain submaximal rates of growth.

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.

An index of diet and eating patterns is a valid measure of diet quality in an Australian population

Diet indices represent an integrated approach to assessing eating patterns and behaviors. The aim of this study was to develop a comprehensive food-based dietary index to reflect adherence to healthy eating recommendations, evaluate the construct validity of the index using nutrient intakes, and evaluate this index in relation to sociodemographic factors, health behaviors, risk factors, and self-assessed health status. Data were analyzed from adult participants of the Australian National Nutrition Survey who completed a 108-item FFQ and a food habits questionnaire (n = 8220). The dietary guideline index (DGI) consisted of 15 items reflecting the dietary guidelines, including dietary indicators of vegetables and legumes, fruit, total cereals, meat and alternatives, total dairy, beverages, sodium, saturated fat, alcoholic beverages, and added sugars. Diet quality was incorporated using indicators relating to whole-grain cereals, lean meat, reduced/low fat dairy, and dietary variety. We investigated associations between the DGI score, sociodemographic factors, health behaviors, chronic disease risk factors, and nutrient intakes. We found associations between the DGI scores and sex, age, income, area-level socioeconomic disadvantage, smoking, physical activity, waist:hip ratio, systolic blood pressure (males only), and self-assessed health status (females only) (all P < 0.05). Higher DGI scores were associated with lower intakes of energy, total fat, and saturated fat and higher intakes of fiber, β-carotene, vitamin C, folate, calcium, and iron (P < 0.05). This food-based dietary index is able to discriminate across a variety of sociodemographic factors, health behaviors, and self-assessed health and reflects intakes of key nutrients.

Getting old and heading south: the academic success of Southerner learners in design cohorts

This paper investigates the relationship between learning style, as determined by Kolb's Learning Style Inventory, age and one measure of academic performance in design assignments for two cohorts of first- and third-year architecture students. The paper focuses on the results of a cross-curriculum learning style survey conducted as part of a project aimed at resolving the learning difficulties of students collaborating in multi-disciplinary and multi-cultural team assignments. The research was conducted to determine how learning style differences in heterogeneous teams might be addressed through pedagogy. In light of evidence in student cohorts of learning style changes towards the learning styles of design teachers as students progress through their studies, this paper demonstrates how these changes reflect a statistically significant relationship between learning styles and academic performance in design assignments.

A weighted version of the Melbourne low-vision ADL index : a measure of disability impact

Objective. To develop a version of the Melbourne Low-Vision ADL Index that measures the personal impact of disability in activities of daily living (ADL's). Also, to determine the relationship between clinical measures of vision impairment and disability impact.

Methods. The Melbourne Low-Vision ADL Index (MLVAI) is a desk-based clinical assessment of disability in ADL's. Ability to perform each item is rated on a five-level descriptive scale from zero to four. In this study, the original version of the MLVAI was modified to measure disability impact. The simple modification involved weighting each item by the importance of that item to the person being tested. Importance was also rated on a five-level scale from zero to four. The validity and reliability of the Weighted Melbourne Low-Vision ADL Index (MLVAIW) was determined for 97 vision-impaired subjects in a cross-sectional study.

Results. Cronbach's alpha coefficient indicated an internal reliability of 0.94, and an intraclass correlation coefficient indicated an overall reliability of 0.88. The standard error of measurement was 24.7 points (out of a possible score of 400). There was a statistically significant difference in test scores between normal subjects and vision-impaired subjects. All vision measures had a high, statistically significant correlation with MLVAIW score. Near-word acuity had the strongest correlation (rs = 0.78, p < 0.001), followed by Melbourne Edge Test contrast sensitivity (rs = -0.72, p < 0.001). Visual field had the weakest correlation (rs = -0.52, p < 0.001). The best predictive model of MLVAIW score incorporated the variables age, near-word acuity, and visual field. Together, these variables accounted for 65.1% of the variance in MLVAIW score.

Conclusions. The MLVAI is highly valid and reliable when weighted by a scale that reflects the personal importance of ADL's. The MLVAIW can provide information over and above that obtained with the usual clinical vision measures and may be used to assess low-vision patients and to measure low-vision rehabilitation outcomes. It is suggested that the assessment of disability using the original MLVAI and the assessment of the impact of disability using the MLVAIW should be kept separate to facilitate the clear interpretation of the outcomes of low-vision rehabilitation.

The simple analytics of optimal growth with illegal migrants

This paper analyses the impact of illegal migration on the optimal path of domestic (resident) consumption. The analysis draws two important conclusions. First, if illegal migrants and domestic labour are perfect substitutes, illegal migration necessarily lowers the long-run per capita consumption of domestic residents. Second, if illegal migrants and domestic labour are imperfect substitutes, the effect on the long-run per capita domestic consumption is ambiguous, however, in the Cobb–Douglas case, the result is clear cut and per capita domestic consumption rises as a result of illegal migration.

Development of a reliable measure of walking within and outside the local neighbourhood: RESIDE's neighborhood physical activity questionnarire.

Background: The RESIDential Environment project (RESIDE) is a longitudinal study evaluating the impact of a new residential design code on walking. Objective: To develop a reliable measure of walking – undertaken within and outside the neighborhood – and overall physical activity. Methods: A test–retest reliability study was undertaken (n = 82, mean age 39 years). The instrument was based on the International Physical Activity Questionnaire (IPAQ-short version) and Active Australia Survey. It measured usual frequency and duration of (1) recreational- and transport-related walking within and outside the neighborhood and (2) other vigorous and moderate physical activities. Results: Reliability of recall of whether participants had walked within (k = 0.84) and outside (0.73) the neighborhood was acceptable. Similarly, recall of frequency and duration of transport and recreational-related walking within the neighborhood was excellent (ICC ≥ 0.82), as was recall of transport-related walking trips outside the neighborhood (ICC ≥ 0.84). Reliability for duration of recreational walking outside the neighborhood was fair to good (ICC = 0.55). The reliability of indices of total physical activity based on MET min/week (ICC = 0.82) and MET min/week dichotomized to ‘sufficient’ physical activity for health (kappa = 0.67) were both acceptable. Conclusions:  The Neighborhood Physical Activity Questionnaire (NPAQ) is sufficiently reliable for studies examining environmental correlates of walking within the neighborhood.

Relationship of glutathione S-transferase genotypes with side-effects of pulsed cyclophsphamide therapy in patients with systemic lupus erythematosus

Aims
Cyclophosphamide (CTX) is an established treatment of severe systemic lupus erythematosus (SLE). Cytotoxic CTX metabolites are mainly detoxified by multiple glutathione S-transferases (GSTs). However, data are lacking on the relationship between the short-term side-effects of CTX therapy and GST genotypes. In the present study, the effects of common GSTM1, GSTT1, and GSTP1 genetic mutations on the severity of myelosuppression, gastrointestinal (GI) toxicity, and infection incidences induced by pulsed CTX therapy were evaluated in patients SLE.
Methods
DNA was extracted from peripheral leucocytes in patients with confirmed SLE diagnosis (n = 102). GSTM1 and GSTT1 null mutations were analyzed by a polymerase chain reaction (PCR)-multiplex procedure, whereas the GSTP1 codon 105 polymorphism (Ile→Val) was analyzed by a PCR-restriction fragment length polymorphism (RFLP) assay.
Results
Our study demonstrated that SLE patients carrying the genotypes with GSTP1 codon 105 mutation [GSTP1*-105I/V (heterozygote) and GSTP1*-105 V/V (homozygote)] had an increased risk of myelotoxicity when treated with pulsed high-dose CTX therapy (Odds ratio (OR) 5.00, 95% confidence interval (CI) 1.96, 12.76); especially in patients younger than 30 years (OR 7.50, 95% CI 2.14, 26.24), or in patients treated with a total CTX dose greater than 1.0 g (OR 12.88, 95% CI 3.16, 52.57). Similarly, patients with these genotypes (GSTP1*I/V and GSTP1*V/V) also had an increased risk of GI toxicity when treated with an initial pulsed high-dose CTX regimen (OR 3.33, 95% CI 1.03, 10.79). However, GSTM1 and GSTT1 null mutations did not significantly alter the risks of these short-term side-effects of pulsed high-dose CTX therapy in SLE patients.
Conclusions
The GSTP1 codon 105 polymorphism, but not GSTM1 or GSTT1 null mutations, significantly increased the risks of short-term side-effects of pulsed high-dose CTX therapy in SLE patients. Because of the lack of selective substrates for a GST enzyme phenotyping study, timely detection of this mutation on codon 105 may assist in optimizing pulsed high-dose CTX therapy in SLE patients.

But they won't come to lectures ... : the impact of recorded lectures on student experience and attendance

The move to provide increasingly flexible platforms for student learning and experience through provision of on-line lecture recordings, is often interpreted by students as meaning attendance at lectures is optional. The trend toward the use of such recordings is often met with resistance from some academic staff who cite anecdotal evidence that student attendance will reduce. This study aimed to explore students’ views of the use of on-line recorded lectures and to measure the impact of this technology on student attendance at lectures. A pre and post evaluation methodology was undertaken using a self-administered questionnaire that gathered both quantitative and qualitative data from students. Overall attendance was recorded at each lecture throughout the semester. Results indicated that attendance remained high throughout the semester and while only a minority of students used the recorded lectures, those who did found them to be helpful to their learning. Most students used the recordings to either supplement their learning or to make up a lecture that they had not been able to attend due to other circumstances. The study also provides evidence that contrary to popular belief, not all Generation Y students aspire to replace lectures with downloadable on-line versions. Many of the students in this study still valued the opportunity for interactive learning provided by face-to-face teaching. Finally, a model that outlines the attributes that contribute to quality teaching is used to describe how recording technology can contribute to positive student experiences and can enhance reflective teaching practices on the part of teachers.

A study on the accuracy of frequency measures and its impact on knowledge discovery in single sequences

In knowledge discovery in single sequences, different results could be discovered from the same sequence when different frequency measures are adopted. It is natural to raise such questions as (1) do these frequency measures reflect actual frequencies accurately? (2) what impacts do frequency measures have on discovered knowledge? (3) are discovered results accurate and reliable? and (4) which measures are appropriate for reflecting frequencies accurately? In this paper, taking three major factors (anti-monotonicity, maximum-frequency and window-width restriction) into account, we identify inaccuracies inherent in seven existing frequency measures, and investigate their impacts on the soundness and completeness of two kinds of knowledge, frequent episodes and episode rules, discovered from single sequences. In order to obtain more accurate frequencies and knowledge, we provide three recommendations for defining appropriate frequency measures. Following the recommendations, we introduce a more appropriate frequency measure. Empirical evaluation reveals the inaccuracies and verifies our findings.