Proposed Spontaneous Generation of Magnetic Fields by Curved Layers of a Chiral Superconductor

We demonstrate that two-dimensional chiral superconductors on curved surfaces spontaneously develop magnetic flux. This geometric Meissner effect provides an unequivocal signature of chiral super- conductivity, which could be observed in layered materials under stress. We also employ the effect to explain some puzzling questions related to the location of zero-energy Majorana modes

Effect of static and dynamic stretching during a full warm-up on athletic performance in athletes

Introduction: Significant evidence indicates that static muscle stretching can acutely reduce muscle force/power production whilst dynamic stretching may increase it. However, study designs have not been appropriate in the majority of studies to determine whether muscle stretching affects performance when it is performed within a full, sports-specific warm-up (Behm et al. 2016). We aimed to determine the effects of static and dynamic stretching during a ’sport-specific warm-up” on running, jumping, agility and flexibility performances in athletes. Methods: Twenty men competing in running-based sports completed a familiarization and four weekly testing sessions. Using a randomized, cross-over design the subjects performed 5-s static passive stretches of lower limb muscles, 3x10-s static stretches, dynamic stretches (5 reps/leg, identical body positions to static stretches) or a non-stretch control condition within a warm-up (5-min general warm-up before stretch, and test-specific, progressive warm-up including maximal efforts after stretch). Researchers were blinded to the warm-up condition, and subjects nominated which condition they believed would yield best performance before the study (subject-level bias) as well as their perception of ‘preparedness’ (1-10 scale) after each warm-up condition. Results: Eighteen of 20 subjects believed that dynamic stretching would yield best performances, however no between-condition differences (p=0.23-0.99) were detected in: (1) 5 m, 20 m or 10-20 m sprint times, (2) squat, countermovement or 3-step running jump heights, or (3) agility T-test time. Magnitude-based inference statistics showed a high likelihood of ‘trivial’ changes. Small and equal post-warm-up increases in sit-and-reach flexibility (1.9-2.4 cm, p5.2/10) for testing when some stretching was performed (no stretch=3.9/10), with no differences between conditions. Discussion: No stretch-specific effect on performance was observed when a warm-up protocol that included low-intensity exercise before muscle stretching was followed by a progressive, test-specific warm-up to maximum exercise intensity in athletes. Thus, although subjects felt better prepared for exercise, short- (5 s) or moderate-duration (30 s) static stretching or dynamic stretching had no group-level effect on performance when used in a full warm-up. Subject belief (i.e. subject-level bias) also did not influence test performances. Based on current and previous data, and contradictory to (some) current recommendations, muscle stretching appears not to influence physical performance when used as part of a full ’sport-specific warm-up’ in athletes. Reference Behm D., Blazevich AJ., Kay AD., McHugh M. (2016). Appl Physiol Nutr Metab, 41, 1-11. Contact [email protected]

A randomized controlled trial on the effectiveness of strength training on clinical and muscle cellular outcomes in patients with prostate cancer during androgen deprivation therapy: rationale and design

Background Studies indicate that strength training has beneficial effects on clinical health outcomes in prostate cancer patients during androgen deprivation therapy. However, randomized controlled trials are needed to scientifically determine the effectiveness of strength training on the muscle cell level. Furthermore, close examination of the feasibility of a high-load strength training program is warranted. The Physical Exercise and Prostate Cancer (PEPC) trial is designed to determine the effectiveness of strength training on clinical and muscle cellular outcomes in non-metastatic prostate cancer patients after high-dose radiotherapy and during ongoing androgen deprivation therapy. Methods/design Patients receiving androgen deprivation therapy for 9-36 months combined with external high-dose radiotherapy for locally advanced prostate cancer are randomized to an exercise intervention group that receives a 16 week high-load strength training program or a control group that is encouraged to maintain their habitual activity level. In both arms, androgen deprivation therapy is continued until the end of the intervention period. Clinical outcomes are body composition (lean body mass, bone mineral density and fat mass) measured by Dual-energy X-ray Absorptiometry, serological outcomes, physical functioning (muscle strength and cardio-respiratory fitness) assessed with physical tests and psycho-social functioning (mental health, fatigue and health-related quality of life) assessed by questionnaires. Muscle cellular outcomes are a) muscle fiber size b) regulators of muscle fiber size (number of myonuclei per muscle fiber, number of satellite cells per muscle fiber, number of satellite cells and myonuclei positive for androgen receptors and proteins involved in muscle protein degradation and muscle hypertrophy) and c) regulators of muscle fiber function such as proteins involved in cellular stress and mitochondrial function. Muscle cellular outcomes are measured on muscle cross sections and muscle homogenate from muscle biopsies obtained from muscle vastus lateralis. Discussion The findings from the PEPC trial will provide new knowledge on the effects of high-load strength training on clinical and muscle cellular outcomes in prostate cancer patients during androgen deprivation therapy. Trial registration ClinicalTrials.gov: NCT0065822

Pregnancy-related pelvic girdle pain: an update

A large number of scientists from a wide range of medical and surgical disciplines have reported on the existence and characteristics of the clinical syndrome of pelvic girdle pain during or after pregnancy. This syndrome refers to a musculoskeletal type of persistent pain localised at the anterior and/or posterior aspect of the pelvic ring. The pain may radiate across the hip joint and the thigh bones. The symptoms may begin either during the first trimester of pregnancy, at labour or even during the postpartum period. The physiological processes characterising this clinical entity remain obscure. In this review, the definition and epidemiology, as well as a proposed diagnostic algorithm and treatment options, are presented. Ongoing research is desirable to establish clear management strategies that are based on the pathophysiologic mechanisms responsible for the escalation of the syndrome's symptoms to a fraction of the population of pregnant women