Independent and combined effects of exercise and vitamin D on muscle morphology, function and falls in the elderly

Regular exercise, particularly progressive resistance training (PRT), is recognized as one of the most effective strategies to prevent age-related muscle loss (sarcopenia), but its effects on muscle function are mixed. However, emerging data indicates that high velocity PRT (fast concentric muscle contractions) is more effective for improving functional outcomes than traditional PRT. In terms of falls prevention, high-challenging balance training programs appear to be most effective. There is also compelling evidence that supplemental vitamin D is an effective therapeutic option for falls prevention. The findings from a recent meta-analysis revealed that supplemental vitamin D at a dose of at least 700–1,000 IU/d or an achieved serum 25(OH)D level of at least 60 nmol/L was associated with reduced falls risk among older individuals. Based on these findings, it is possible that the combination of exercise and vitamin D could have a synergistic effect on muscle morphology and function, particularly since both interventions have been shown to have beneficial effects on type II “fast twitch” muscle fibers and systemic inflammation, which have both been linked to losses in muscle mass and function. Unfortunately however, the findings from the limited number of factorial 2 × 2 design RCTs indicate that additional vitamin D does not enhance the effects of exercise on measures of muscle morphology, function or falls risk. However, none of these trials were adequately powered to detect a “synergistic” effect between the two treatment strategies, but it is likely that if an exercise-by-vitamin D interaction does exist, it may be limited to situations when vitamin D deficiency/insufficiency is corrected. Further targeted research in “high risk” groups is still needed to address this question, and evaluate whether there is a threshold level of serum 25(OH)D to maximize the effects of exercise on muscle and falls risk.

Leadership narratives : women leaders in independent schools, Victoria 2004-2008

This thesis investigates the professional work narratives of twelve women Junior Heads and the influence of dominant leadership discourses on shaping leadership identities. Leadership narratives reveal how power and agency are negotiated through discourses of paradox, idealism and dissent. These discourses were used by the women as positioning strategies to discursively navigate ambiguity and contradiction arising from the micro-politics of power relationships and gendered discourses within their situated practice.

A needs based methodology for classifying construction clients and selecting contractors : comment

This note is a comment on Chinyio, E.A., Olomolaiye, P.O., Kometa, S.T. and Harris, F.C. (1998) A needs based methodology for classifying construction clients and selecting contractors, Construction Management and Economics, 16(1), 91± 8, which describes research aimed at classifying clients by their needs rather than by the traditional public/private/developer approach. The paper also proposes a new method of selecting contractors by matching clients’ needs to contractors’ ability to satisfy them. The note offers constructive criticism of some aspects of the analysis.

The effects of topological inaccuracy in evolutionary trees on the phylogenetic comparative method of independent contrasts

Computer simulations were used to test the effect of increasing phylogenetic topological inaccuracy on the results obtained from correlation tests of independent contrasts. Predictably, increasing the number of disruptions in the tree increases the likelihood of significant error in the r values produced and in the statistical conclusions drawn from the analysis. However, the position of the disruption in the tree is important: Disruptions closer to the tips of the tree have a greater effect than do disruptions that are close to the root of the tree. Independent contrasts derived from inaccurate topologies are more likely to lead to erroneous conclusions when there is a true significant relationship between the variables being tested (i.e., they tend to be conservative). The results also suggest that random phylogenies perform no better than nonphylogenetic analyses and, under certain conditions, may perform even worse than analyses using raw species data. Therefore, the use of random phylogenies is not beneficial in the absence of knowledge of the true phylogeny.

Independent functions of yeast Pcf11p in pre-mRNA 3´ end processing and in transcription termination

Pcf11p, an essential subunit of the yeast cleavage factor IA, is required for pre-mRNA 3' end processing, binds to the C-terminal domain (CTD) of the largest subunit of RNA polymerase II (RNAP II) and is involved in transcription termination. We show that the conserved CTD interaction domain (CID) of Pcf11p is essential for cell viability. Interestingly, the CTD binding and 3' end processing activities of Pcf11p can be functionally uncoupled from each other and provided by distinct Pcf11p fragments in trans. Impaired CTD binding did not affect the 3' end processing activity of Pcf11p and a deficiency of Pcf11p in 3' end processing did not prevent CTD binding. Transcriptional run-on analysis with the CYC1 gene revealed that loss of cleavage activity did not correlate with a defect in transcription termination, whereas loss of CTD binding did. We conclude that Pcf11p is a bifunctional protein and that transcript cleavage is not an obligatory step prior to RNAP II termination.

Managerial share ownership and discretionary accruals in Australia : do independent and executive directors have different incentives?

We examine the relation between managerial share ownership (MSO) and discretionary accruals in Australia. We find a positive relation between MSO and discretionary accruals up to a certain level of MSO followed by a negative relation (inverse U-shaped). We suggest that these unique results are a result of certain Australian institutional features that are markedly different to those in the US and the UK and imply that the ownership-discretionary accruals relation is context specific with the wider corporate governance systems influencing the theorised incentive effects. We also posit that executive directors and independent directors have different ownership-discretionary accruals incentives and report results consistent with this proposition.

The impact of client attitudes on the selection of contractors

This research is concerned with identifying prequalification criteria that both clients and contractors believe are good indicators of future construction performance. Criteria used in the past have been developed by clients in a largely idiosyncratic manner with little or no consultation with the contractors affected. The methodology chosen for the research was a survey which probed stakeholder attitudes to commonly used prequalification criteria. This was carried out via a postal questionnaire involving contactors and clients across Australia. The data was analysed using Discriminant Analysis, which is a multivariate statistical approach that determines the differences between groups. The research is structured around 39 criteria that were developed as part of a whole-of–government task force into best practice in procurement. The findings identified the most important criteria from both a client’s perspective, and a contractor’s perspective. The purpose was to discover if those differences reduce the effectiveness of the procurement process. This paper contributes to a more clarified understanding of the impact or contrasting views between the stakeholders involved in the prequalification process. This work is innovative because it is one of a few pieces of research that showed that clients and contractors do actually have divergent opinions on the importance of some criteria currently relied upon in the decision making process. The most important prequalification criteria are identified and possible reasons for these differences are discussed.

Media-independent knowledge representation via UMART : unified mental annotation and retrieval tool

Multimedia information is now routinely available in the forms of text, pictures, animation and sound. Although text objects are relatively easy to deal with (in terms of information search and retrieval), other information bearing objects (such as sound, images, animation) are more difficult to index. Our research is aimed at developing better ways of representing multimedia objects by using a conceptual representation based on Schank's conceptual dependencies. Moreover, the representation allows for users' individual interpretations to be embedded in the system. This will alleviate the problems associated with traditional semantic networks by allowing for coexistence of multiple views of the same information. The viability of the approach is tested, and the preliminary results reported.