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Changes in morphology and physiology of an East Mediterranean sponge in different habitats

The sponge Tetilla sp. (Tetractinomorpha: Tetillidae) is a common species in the eastern Mediterranean. This sponge inhabits four different habitat types differing in wave impact and irradiance levels. Two of these habitats (a shallow cave and deep water) are characterized by relatively calm water, whereas the other two (shallow exposed site and tide pools) are in turbulent water with high energy flow. The present study examined the influence of physical (depth, illumination and water motion) and biotic factors on morphology, skeletal plasticity and reproductive traits among the four spatially separated populations. Sponges from tidal pools had significantly larger body volume than sponges from deep water and from shallow caves (ANOVA: tidal-deep P< 0.0001; tidal-shallow caves P< 0.05). Sponges from exposed habitats were significantly larger than deep-water sponges (ANOVA: P=0.01). In addition, individuals from tide pools and from the exposed habitat had a significantly higher proportion of structural silica than sponges from the calmer deep water and from the cave sites. Oxea spicules in sponges from the calm habitats were significantly shorter than in those from the tidal pools and the exposed habitats. The percentage of spicules out of a sponge's dry weight in individuals transplanted from deep (calm) to shallow (turbulent) water significantly increased by 21.9&PLUSMN; 12.9%. The new spicule percentage did not differ significantly from that of sponges originally from shallow water. Oocyte diameter differed significantly between habitats. The maximal size of mature eggs was found in deep-water sponges in June (97&PLUSMN; 5 μ m). In the shallow habitats, a smaller maximal oocyte diameter was found in the cave, in May (56.5&PLUSMN; 3 μ m). Furthermore, oocyte density in shallow-water sponges was highest in May and decreased in June (with 88.2&PLUSMN; 9 and 19.3&PLUSMN; 9 oocytes mm(-2), respectively). At the same time (June), oocyte density of deep-water sponges had just reached its maximum (155&PLUSMN; 33.7 oocytes mm(-2)). The difference in oocyte size and density between deep- and shallow-water individuals indicates an earlier gamete release in the shallow sponge population. The results suggest that plasticity in skeletal design of this sponge indicates a trade off between spicule production and investment in reproduction.

Steroid Androgen Exposure during Development Has No Effect on Reproductive Physiology of Biomphalaria glabrata

Funding: The research presented in this manuscript was wholly funded by National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), https://www.nc3rs.org.uk/. ‘The Snail Assay as an Alternative to the Rodent Hershberger Assay for Detecting Androgens and Anti-androgens’ funding reference: G0900802/1 to SJ, EJR, CSJ, and LRN. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Documenting reproduction and inequality : revisiting Jean Anyon’s “Social class and school knowledge”

Jean Anyon’s (1981) “Social class and school knowledge” was a landmark work in North American educational research. It provided a richly detailed qualitative description of differential, social-class-based constructions of knowledge and epistemological stance. This essay situates Anyon’s work in two parallel traditions of critical educational research: the sociology of the curriculum and classroom interaction and discourse analysis. It argues for the renewed importance of both quantitative and qualitative research on social reproduction and equity in the current policy context.

A pilot randomised control trial of general practitioner and exercise physiologist interventions to reduce primary cardiovascular risk in overweight patients [Abstract]

Aims & Rationale/Objectives: With the knowledge that overweight is a major public health concern in Australia, that a multidisciplinary team approach to the management of lifestyle-related conditions is supported, and that the Australian Government recently recognised the role of the exercise physiologist (EP) in reducing the health burden of disease by their inclusion for reimbursement under the Medicare Plus scheme, this study sought to undertake a pilot RCT to compare GP and EP interventions to reduce primary cardiovascular risk in the overweight general practice population. Methods and Measures: Overweight patients recruited by a convenience sample of GPs were randomised into one of three arms: the control group, or the GP or EP intervention group (in which patients received either five GP or five EP consultations over 24 weeks). Patients had baseline, 12- and 24-week measures of body composition and cardio-respiratory fitness, and completed baseline and end-of-study surveys, fasting lipids and glucose. GPs and EPs completed an end-of-study survey. Results:Sixty-seven patients attended the baseline assessment. Overall retention rate was 67%. Patients were generally satisfied with the effectiveness of the interventions and their weight reduction. Favourable trends in BMI, weight, glucose and exercise levels for GP and EP intervention groups and in physical activity levels for all groups Conclusions: This study supports the feasibility of a RCT of GP and EP interventions for decreasing primary cardiovascular risk in the overweight general practice population.

Plasma ATP concentration and venous oxygen content in the forearm during dynamic handgrip exercise

Background: It has been proposed that adenosine triphosphate (ATP) released from red blood cells (RBCs) may contribute to the tight coupling between blood flow and oxygen demand in contracting skeletal muscle. To determine whether ATP may contribute to the vasodilatory response to exercise in the forearm, we measured arterialised and venous plasma ATP concentration and venous oxygen content in 10 healthy young males at rest, and at 30 and 180 seconds during dynamic handgrip exercise at 45% of maximum voluntary contraction (MVC). Results: Venous plasma ATP concentration was elevated above rest after 30 seconds of exercise (P < 0.05), and remained at this higher level 180 seconds into exercise (P < 0.05 versus rest). The increase in ATP was mirrored by a decrease in venous oxygen content. While there was no significant relationship between ATP concentration and venous oxygen content at 30 seconds of exercise, they were moderately and inversely correlated at 180 seconds of exercise (r = -0.651, P = 0.021). Arterial ATP concentration remained unchanged throughout exercise, resulting in an increase in the venous-arterial ATP difference. Conclusions: Collectively these results indicate that ATP in the plasma originated from the muscle microcirculation, and are consistent with the notion that deoxygenation of the blood perfusing the muscle acts as a stimulus for ATP release. That ATP concentration was elevated just 30 seconds after the onset of exercise also suggests that ATP may be a contributing factor to the blood flow response in the transition from rest to steady state exercise.

Exercise intensity influences NEAT in overweight and obese adults

PURPOSE: To determine the effect of acute bouts of moderate- and high-intensity walking exercise on non-exercise activity thermogenesis (NEAT) in overweight and obese adults. ---------- METHOD: 16 participants performed a single bout of either moderate-intensity walking exercise (MIE) or high-intensity walking exercise (HIE) on two separate occasions. The MIE consisted of walking for 60 minutes on a motorized treadmill at 6 km.h. The 60-minute HIE session consisted of walking in 5-min intervals at 6 km.h and 10% grade followed by 5-min at 0% grade. NEAT was assessed by accelerometer on three days before, the day of, and three days following the exercise sessions. ---------- RESULTS: There was no significant difference in NEAT vector magnitude (counts.min) between the pre-exercise period (days 1-3) and the exercise day (day 4) for either MIE or HIE protocol. In addition, there was no change in NEAT during the three days following the MIE session, however NEAT increased by 16% on day 7 (post-exercise) compared with exercise day (P = 0.32). However during the post-exercise period following the HIE session, NEAT was increased by 25% on day 7 compared with the exercise day (P = 0.08), and by 30-33% compared with pre-exercise period (day 1, day 2 and day 3); P = 0.03, 0.03, 0.02, respectively. ---------- CONCLUSION: A single bout of either MIE or HIE did not alter NEAT on the exercise day or on the first two days following the exercise session. However, monitoring NEAT on a third day allowed the detection of a 48-h delay in increased NEAT after performing HIE. A longer-term intervention is needed to determine the effect of accumulated exercise sessions over a week on NEAT.

An egg apparatus-specific enhancer of Arabidopsis, identified by enhancer detection

Despite a central role in angiosperm reproduction, few gametophyte-specific genes and promoters have been isolated, particularly for the inaccessible female gametophyte (embryo sac). Using the Ds-based enhancer-detector line ET253, we have cloned an egg apparatus-specific enhancer (EASE) from Arabidopsis (Arabidopsis thaliana). The genomic region flanking the Ds insertion site was further analyzed by examining its capability to control gusA and GFP reporter gene expression in the embryo sac in a transgenic context. Through analysis of a 5' and 3' deletion series in transgenic Arabidopsis, the sequence responsible for egg apparatus-specific expression was delineated to 77 bp. Our data showed that this enhancer is unique in the Arabidopsis genome, is conserved among different accessions, and shows an unusual pattern of sequence variation. This EASE works independently of position and orientation in Arabidopsis but is probably not associated with any nearby gene, suggesting either that it acts over a large distance or that a cryptic element was detected. Embryo-specific ablation in Arabidopsis was achieved by transactivation of a diphtheria toxin gene under the control of the EASE. The potential application of the EASE element and similar control elements as part of an open-source biotechnology toolkit for apomixis is discussed.

Comparing exercise prescribed with exercise completed : effects of gender and mode of exercise

The purpose of this study was to compare the amount of exercise prescribed with the amount completed between two different modes of training intervention and between the sexes. Thirty-two men (mean age = 39.1 years, body mass index = 32.9 kg · m-2) and women (mean age = 39.6 years, body mass index = 32.1 kg · m-2) were prescribed traditional resistance training or light-resistance circuit training for 16 weeks. Lean mass and fat mass were determined by dual-energy X-ray absorptiometry at weeks 1 and 16. A completion index was calculated to provide a measure of the extent to which participants completed exercise training relative to the amount of exercise prescribed. The absolute amount of exercise completed by the circuit training group was significantly greater than the amount prescribed (P < 0.0001). The resistance training group consistently under-completed relative to the amount prescribed, but the difference was not significant. The completion index for the circuit training group (26 ± 21.7%) was significantly different from that of the resistance training group (-7.4 ± 3.0%). The completion index was not significantly different between men and women in either group. These data suggest that overweight and obese individuals participating in light-resistance circuit training complete more exercise than is prescribed. Men and women do not differ in the extent to which they over- or under-complete prescribed exercise.

Reproduction, mediation, and experience : virtual reality, motion capture and early modern theatre

This article investigates virtual reality representations of performance in London’s late sixteenth-century Rose Theatre, a venue that, by means of current technology, can once again challenge perceptions of space, performance, and memory. The VR model of The Rose represents a virtual recreation of this venue in as much detail as possible and attempts to recover graphic demonstrations of the trace memories of the performance modes of the day. The VR model is based on accurate archeological and theatre historical records and is easy to navigate. The introduction of human figures onto The Rose’s stage via motion capture allows us to explore the relationships between space, actor and environment. The combination of venue and actors facilitates a new way of thinking about how the work of early modern playwrights can be stored and recalled. This virtual theatre is thus activated to intersect productively with contemporary studies in performance; as such, our paper provides a perspective on and embodiment of the relation between technology, memory and experience. It is, at its simplest, a useful archiving project for theatrical history, but it is directly relevant to contemporary performance practice as well. Further, it reflects upon how technology and ‘re-enactments’ of sorts mediate the way in which knowledge and experience are transferred, and even what may be considered ‘knowledge.’ Our work provides opportunities to begin addressing what such intermedial confrontations might produce for ‘remembering, experiencing, thinking and imagining.’ We contend that these confrontations will enhance live theatre performance rather than impeding or disrupting contemporary performance practice. Our ‘paper’ is in the form of a video which covers the intellectual contribution while also permitting a demonstration of the interventions we are discussing.

Physical activity and nutrition program for seniors (PANS) : protocol of a randomized controlled trial

Background Along with reduced levels of physical activity, older Australian's mean energy consumption has increased. Now over 60% of older Australians are considered overweight or obese. This study aims to confirm if a low-cost, accessible physical activity and nutrition program can improve levels of physical activity and diet of insufficiently active 60-70 year-olds. Methods/Design This 12-month home-based randomised controlled trial (RCT) will consist of a nutrition and physical activity intervention for insufficiently active people aged 60 to 70 years from low to medium socio-economic areas. Six-hundred participants will be recruited from the Australian Federal Electoral Role and randomly assigned to the intervention (n = 300) and control (n = 300) groups. The study is based on the Social Cognitive Theory and Precede-Proceed Model, incorporating voluntary cooperation and self-efficacy. The intervention includes a specially designed booklet that provides participants with information and encourages dietary and physical activity goal setting. The booklet will be supported by an exercise chart, calendar, bi-monthly newsletters, resistance bands and pedometers, along with phone and email contact. Data will be collected over three time points: pre-intervention, immediately post-intervention and 6-months post-study. Discussion This trial will provide valuable information for community-based strategies to improve older adults' physical activity and dietary intake. The project will provide guidelines for appropriate sample recruitment, and the development, implementation and evaluation of a minimal intervention program, as well as information on minimising barriers to participation in similar programs.