Mitochondrial DNA Damage Following Isolated Muscle Exercise: A Preliminary Investigation Into HO-1 Gene Expression

PURPOSE: This preliminary investigation was designed to test the hypothesis that high intensity single-leg exercise can cause extensive cell DNA damage, which subsequently may affect the expression of the HO-1 gene. METHODS: Six (n=6) apparently healthy male participants (age 27 + 7 yrs, stature 174 + 12 cm, body mass 79 + 4 kg and BMI 24 + 4 kg/m2) completed 100 isolated and continuous maximal concentric contractions (minimum force = 200 N, speed of contraction = 60°/sec) of the rectus femoris muscle. Using a spring-loaded and reusable Magnum biopsy gun with a 16-gauge core disposable biopsy needle, skeletal muscle micro biopsy tissue samples were extracted at rest and following exercise. mRNA gene expression was determined via two-step quantitative real-time PCR using GAPDH as a reference gene. RESULTS: The average muscle force production was 379 + 179 N. High intensity exercise increased mitochondrial 8-OHdG concentration (P < 0.05 vs. rest) with a concomitant decrease in total antioxidant capacity (P < 0.05 vs. rest). Exercise also increased protein oxidation as quantified by protein carbonyl concentration (P < 0.05 vs. rest). HO-1 expression increased (> 2-fold change vs. rest) following exercise, and it is postulated that this change was not significant due to low subject numbers (P > 0.05). CONCLUSION: These preliminary findings tentatively suggest that maximal concentric muscle contractions can cause intracellular DNA damage with no apparent disruption to the expression of the antioxidant stress protein HO-1. Moreover, it is likely that cell oxidant stress is required to activate the signal transduction cascade related to the expression of HO-1. A large-scale study incorporating a greater subject number is warranted to fully elucidate this relationship.

Stable Isolated Metal Atoms as Active Sites for Photocatalytic Hydrogen Evolution

The process of using solar energy to split water to produce hydrogen assisted by an inorganic semiconductor is crucial for solving our energy crisis and environmental problems in the future. However, most semiconductor photocatalysts would not exhibit excellent photocatalytic activity without loading suitable co-catalysts. Generally, the noble metals have been widely applied as co-catalysts, but always agglomerate during the loading process or photocatalytic reaction. Therefore, the utilization efficiency of the noble co-catalysts is still very low on a per metal atom basis if no obvious size effect exists, because heterogeneous catalytic reactions occur on the surface active atoms. Here, for the first time, we have synthesized isolated metal atoms (Pt, Pd, Rh, or Ru) stably by anchoring on TiO2, a model photocatalystic system, by a facile one-step method. The isolated metal atom based photocatalysts show excellent stability for H-2 evolution and can lead to a 6-13-fold increase in photocatalytic activity over the metal clusters loaded on TiO2 by the traditional method. Furthermore, the configurations of isolated atoms as well as the originality of their unusual stability were analyzed by a collaborative work from both experiments and theoretical calculations.

‘Plugging the Gap’: Shared Education and the promotion of community relations through schools in Northern Ireland

Although there is no consensus amongst educationalists as to the role schools play as drivers of hostilities in divided societies, there is broad agreement that they can facilitate more positive intergroup relations. In Northern Ireland the promotion of school based inter-group contact has been offered as a means through which this can happen. Until 2007, the approach was twofold, reflected on the one hand in short-term contact opportunities for pupils in predominantly Catholic and Protestant schools, and on the other, in support for integrated schools which educate Catholics and Protestants together. In 2007 the Shared Education Programme was introduced to ‘bridge the gap’ between short-term opportunities for contact, and ‘full immersion’ integrated schools. Informed by contact theory, shared education offers curriculum based interaction between pupils attending all school types, aimed at promoting the type of contact likely to reduce negative social attitudes and ultimately contribute to social harmony. In this paper, we examine the impact of shared education thus far. Our analysis suggests that whilst shared education is generally effective in promoting positive assessments of other group members, there is a danger that programme impact may be inhibited by the foregrounding of educational over reconciliation priorities. Appreciating that the downplaying reconciliation objectives may have been necessary when the programme was established in order to maximize recruitment to it, we argue that if the full potential of shared education is to be realized, moving forward, it is important for schools to engage with issues of group differences.

Few-cycle driven relativistically oscillating plasma mirrors:A source of intense isolated attosecond pulses

The conditions required for the production of isolated attosecond pulses from relativistically oscillating mirrors (ROM) are investigated numerically and experimentally. In simulations, carrier-envelope-phase-stabilized three-cycle pulses are found to be sufficient to produce isolated attosecond pulses, while two-cycle pulses will predominantly lead to isolated attosecond pulses even in the absence of carrier-envelope stabilization. Using a state-of-the-art laser system delivering three-cycle pulses at multiple-terawatt level, we have generated higher harmonics up to 70 eV photon energy via the ROM mechanism. The observed spectra are in agreement with theoretical expectations and highlight the potential of few-cycle-driven ROM harmonics for intense isolated attosecond pulse generation for performing extreme ultraviolet-pump extreme ultraviolet-probe experiments. © 2012 American Physical Society.

Recruiting schools, adolescents and parents to a sexual-health trial: experiences, challenges and lessons learned from the Jack Trial

Background
Recruitment to school-based randomised trials is challenging; even more so when the focus of the study is a sensitive issue such as sexual health. The Jack Feasibility Trial aims to determine the facilitators and barriers to recruitment and retention to a school-based sexual health trial and identify optimal multi-level strategies for a full trial.
Method
The Jack Trial is an NIHR-funded feasibility study of a film-based sexual health intervention, recruiting over 800 adolescents from 8 post-primary schools in Northern Ireland. In order to examine the feasibility of piloted recruitment and retention methods and assess acceptability of participation across the range of schools and individuals approached, we analysed qualitative data from triangulated sources including a parents’ survey and semi-structured interviews with principals, vice-principals, teachers and parents recruited to the study.
Results
With reference to Social Learning Theory, we identified a number of individual, behavioural and environmental level factors which influenced recruitment and retention. Commonly identified facilitators included the perceived relevance and potential benefit of the intervention to adolescents, the credibility of the organisation running the study, support offered by trial staff, and financial incentives. Key barriers were prior commitment to other research, lack of time and resources, and perceptions that the intervention was incompatible with adolescent needs or school ethos.
Conclusion
This study highlights pertinent general and trial-specific facilitators and barriers to recruitment to a sexual health trial in a school setting, which will prove useful for successful conduct of future trials with schools, adolescents and parents.

A Pilot Study of Reciprocal Peer Tutoring in Irish Medium Schools

A pilot study to investigate the effects of mathematics peer tutoring in Irish medium primary schools was undertaken. Five schools and 90 students took part in the pilot. Materials and resources that had previously been shown to work in English medium Scottish schools were translated into Irish by CCEA. Irish medium teachers attended three professional development days. Teachers implemented the peer tutoring techniques during mathematics lessons during a period of 16 weeks. Changes in attainment were measures with an Irish translation of the Scottish Survey of Achievement Mathematics Test. Results were positive. Student attainment was significantly raised during the 16-week implementation period by over one standard deviation. This equated to one-year’s worth of mathematics development during this time period. Results must be treated with caution. No control group was used in the pilot study. However, results are very promising and indicate that reciprocal role peer tutoring may be a useful pedagogy in Irish medium education. Further work would be required to establish this definitively.

Generating Isolated Elliptically Polarized Attosecond Pulses Using Bichromatic Counterrotating Circularly Polarized Laser Fields

We theoretically demonstrate the possibility to generate both trains and isolated attosecond pulses with high ellipticity in a practical experimental setup. The scheme uses circularly polarized, counterrotating two-color driving pulses carried at the fundamental and its second harmonic. Using a model Ne atom, we numerically show that highly elliptic attosecond pulses are generated already at the single-atom level. Isolated pulses are produced by using few-cycle drivers with controlled time delay between them.