Vitamin C inhibits endothelial cell apoptosis in congestive heart failure

Background - Proinflammatory cytokines like tumor necrosis factor- and oxidative stress induce apoptotic cell death in endothelial cells (ECs). Systemic inflammation and increased oxidative stress in congestive heart failure (CHF) coincide with enhanced EC apoptosis and the development of endothelial dysfunction. Therefore, we investigated the effects of antioxidative vitamin C therapy on EC apoptosis in CHF patients. Methods and Results - Vitamin C dose dependently suppressed the induction of EC apoptosis by tumor necrosis factor- and angiotensin II in vitro as assessed by DNA fragmentation, DAPI nuclear staining, and MTT viability assay. The antiapoptotic effect of vitamin C was associated with reduced cytochrome C release from mitochondria and the inhibition of caspase-9 activity. To assess EC protection by vitamin C in CHF patients, we prospectively randomized CHF patients in a double-blind trial to vitamin C treatment versus placebo. Vitamin C administration to CHF patients markedly reduced plasma levels of circulating apoptotic microparticles to 32±8% of baseline levels, whereas placebo had no effect (87±14%, P<0.005). In addition, vitamin C administration suppressed the proapoptotic activity on EC of the serum of CHF patients (P<0.001). Conclusions - Administration of vitamin C to CHF patients suppresses EC apoptosis in vivo, which might contribute to the established functional benefit of vitamin C supplementation on endothelial function

Of grit and grace: negotiating puberty, surviving, and succeeding in professional ballet

This is the author accepted manuscript. The final version is available from Human Kinetics via the DOI in this recordExperiences of puberty and how individuals adapt to puberty may be integral to success in ballet; however, there is a paucity of current research in this area. This study explores the lived experiences of nine professional ballet dancers to capture the journey of negotiating puberty in a ballet context. An interpretative phenomenological analysis approach was employed with semistructured interviews utilized to gather rich, descriptive accounts from nine professional ballet dancers from the United Kingdom and United States. Lived experiences were characterized by conflict and struggle, coming to terms with physical changes and possessing grit and grace in order to successfully negotiate puberty, and to succeed and survive in professional ballet. Accepting physical and esthetic strengths and weaknesses and learning how to adapt or how to compensate for weaknesses was described as pivotal. Factors such as social support, the timing and extent of pubertal changes, dance teacher behaviors, and the ballet training context influenced the extent to which dancers experienced conflict and struggle and how easily they were able to come to terms with their adult physique. Further research is needed to explore the implications of maturing and developing within the context of ballet training and to develop strategies to better facilitate healthy development in ballet

On-time maturation in female adolescent ballet dancers: Learning from lived experiences

This is the final version. Available on open access from SAGE Publications via the DOI in this recordThis study employed semi-structured interviews and Interpretative Phenomenological Analysis to explore experiences of on-time maturation in nine adolescent ballet dancers from across three vocational ballet schools in the United Kingdom. Two themes were identified as central to their experiences: ‘A right and a wrong way to grow’, and fitting in and moving forward. Instead of perceiving themselves as ‘average’ and experiencing a relatively easy pubertal transition, on-time dancers described unique challenges associated with a fluctuation between fitting in and not fitting in within their social context. The implications of on-time maturation in this context are complex and do not appear to follow the same trajectory as early maturing ballet dancers nor on-time non-dancers

Cuts and flows of cell complexes

We study the vector spaces and integer lattices of cuts and flows associated with an arbitrary finite CW complex, and their relationships to group invariants including the critical group of a complex. Our results extend to higher dimension the theory of cuts and flows in graphs, most notably the work of Bacher, de la Harpe and Nagnibeda. We construct explicit bases for the cut and flow spaces, interpret their coefficients topologically, and give sufficient conditions for them to be integral bases of the cut and flow lattices. Second, we determine the precise relationships between the discriminant groups of the cut and flow lattices and the higher critical and cocritical groups with error terms corresponding to torsion (co)homology. As an application, we generalize a result of Kotani and Sunada to give bounds for the complexity, girth, and connectivity of a complex in terms of Hermite's constant.Comment: 30 pages. Final version, to appear in Journal of Algebraic Combinatoric

Field validation of radar systems for monitoring bird migration

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.Advances in information technology are increasing the use of radar as a tool to investigate and monitor bird migration movements. We set up a field campaign to compare and validate outputs from different radar systems. Here we compare the pattern of nocturnal bird migration movements recorded by four different radar systems at a site in southern Sweden. Within the range of the weather radar (WR) Ängelholm, we operated a "BirdScan" (BS) dedicated bird radar, a standard marine radar (MR), and a tracking radar (TR). The measures of nightly migration intensities, provided by three of the radars (WR, BS, MR), corresponded well with respect to the relative seasonal course of migration, while absolute migration intensity agreed reasonably only between WR and BS. Flight directions derived from WR, BS and TR corresponded very well, despite very different sample sizes. Estimated mean ground speeds differed among all four systems. The correspondence among systems was highest under clear sky conditions and at high altitudes. Synthesis and applications. While different radar systems can provide useful information on nocturnal bird migration, they have distinct strengths and weaknesses, and all require supporting data to allow for species level inference. Weather radars continuously detect avian biomass flows across a wide altitude band, making them a useful tool for monitoring and predictive applications at regional to continental scales that do not rely on resolving individuals. BirdScan and marine radar's strengths are in local and low altitude applications, such as collision risks with man-made structures and airport safety, although marine radars should not be trusted for absolute intensities of movement. In quantifying flight behaviour of individuals, TR is the most informative.We acknowledge the support provided by COST – European Cooperation in Science and Technology through the Action ES1305 ‘European Network for the Radar Surveillance of Animal Movement’ (ENRAM) in facilitating this collaboration. The study received financial support from Gyllenstierna Krapperup ́s Foundation and the Centre for Animal Movement Research (CAnMove) financed by a Linnaeus grant (349-2007-8690) from the Swedish Research Council and Lund University

A novel method for assessing design fidelity in web-based behavioral interventions.

Objective: Delivery is one of the most common ways of assessing fidelity in behavioral interventions.However, there is a lack of research reporting on how well an intervention protocol reflects its proposed theoretical principles (design fidelity). This study presents a systematic method for assessing design fidelity and applies it to the eMotion web-based intervention targeting physical activity and depression.Method: The eMotion intervention comprises of 13 web-based modules, designed according to an underlying intervention map. An independent rater with expertise in behavior change coded the presenceor absence of behavior change techniques (BCTs) in the content of eMotion. Results of coding werecompared to the intervention designers’ a priori specification for interrater reliability. Results: Afterdiscussion, the independent rater and the intervention designer had a high agreement for the presence ofBCTs relating to behavioral activation (AC1 0.91) with “demonstration of behavior” and “monitoringof emotional consequences” having the lowest agreement (AC1 0.4). There was also high agreementfor the presence of BCTs targeting physical activity (AC1 0.88) with “demonstration of behavior” and “monitoring of emotional consequences” having the lowest agreement (AC1 0.4). The eMotion description was then amended to align the interrater agreement. Conclusions: This study presents a novelmethod for assessing design fidelity. Developers of behavioral (and other multicomponent) interventions are encouraged to develop and refine this method and assess design fidelity in future interventions to ensure BCTs are operationalized as intended

Steam reforming on transition-metal carbides from density-functional theory

A screening study of the steam reforming reaction (CH_4 + H_2O -> CO + 3H_2) on early transition-metal carbides (TMC's) is performed by means of density-functional theory calculations. The set of considered surfaces includes the alpha-Mo_2C(100) surfaces, the low-index (111) and (100) surfaces of TiC, VC, and delta-MoC, and the oxygenated alpha-Mo_2C(100) and TMC(111) surfaces. It is found that carbides provide a wide spectrum of reactivities towards the steam reforming reaction, from too reactive via suitable to too inert. The reactivity is discussed in terms of the electronic structure of the clean surfaces. Two surfaces, the delta-MoC(100) and the oxygen passivated alpha-Mo_2C(100) surfaces, are identified as promising steam reforming catalysts. These findings suggest that carbides provide a playground for reactivity tuning, comparable to the one for pure metals.Comment: 6 pages, 4 figure