Bats Use Magnetite to Detect the Earth's Magnetic Field

While the role of magnetic cues for compass orientation has been confirmed in numerous animals, the mechanism of detection is still debated. Two hypotheses have been proposed, one based on a light dependent mechanism, apparently used by birds and another based on a “compass organelle” containing the iron oxide particles magnetite (Fe3O4). Bats have recently been shown to use magnetic cues for compass orientation but the method by which they detect the Earth's magnetic field remains unknown. Here we use the classic “Kalmijn-Blakemore” pulse re-magnetization experiment, whereby the polarity of cellular magnetite is reversed. The results demonstrate that the big brown bat Eptesicus fuscus uses single domain magnetite to detect the Earths magnetic field and the response indicates a polarity based receptor. Polarity detection is a prerequisite for the use of magnetite as a compass and suggests that big brown bats use magnetite to detect the magnetic field as a compass. Our results indicate the possibility that sensory cells in bats contain freely rotating magnetite particles, which appears not to be the case in birds. It is crucial that the ultrastructure of the magnetite containing magnetoreceptors is described for our understanding of magnetoreception in animals

X-ray Computed Tomography for Failure Mechanism Characterisation within Layered Pouch Cells

Lithium-ion battery (LIB) safety is a multi-scale problem: from the whole-cell architecture to its composite internal 3D microstructures. Substantial research is required to standardise failure assessments and optimise cell designs to reduce the risks of LIB failure. In this work, the failure response of a 1 Ah layered pouch cell with a commercially available NMC cathode and graphite anode at 100 % SOC (4.2 V) is investigated. The mechanisms of two abuse methods; mechanical (by nail penetration) and thermal (by accelerating rate calorimetry) are compared by using a suite of post-mortem analysis methods. Post-mortem whole-cell architectural changes and electrode layer deformations were analysed for both mechanisms using non-invasive X-ray computed tomography. Furthermore, changes to electrode surfaces, bulk microstructures and particle morphologies are compared by following a proposed cell disassembly and post-mortem sample preparation methodology. Building on the insights into critical architectural weak points, electrode behaviours and particle cracks, the reliability of X-ray computed tomography as a guide for LIB failure assessment is demonstrated

Is equipoise a useful concept to justify randomised controlled trials in the cultural context of Pakistan? A survey of clinicians in relation to a trial of talking therapy for young people who self-harm

Background: Clinical equipoise, also defined as the uncertainty principle, is considered essential when recruiting subjects to a clinical trial. However, equipoise is threatened when clinicians are influenced by their own preferences. Little research has investigated equipoise in the context of trial recruitment. Methods: This cross-sectional survey sought clinicians’ views (operationalised as 11 statements relating to treatments offered in a trial of a psychological intervention for young people) about equipoise and individual treatment preferences in the context of moral justification for recruiting young people at risk of self-harm or suicide to a randomised controlled trial (RCT) to evaluate the Youth Culturally Adapted Manual Assisted Psychological Intervention (Y-CMAP) in Pakistan. We compared the views of clinicians involved in Y-CMAP RCT recruitment to those of a sample of clinicians not involved in trial recruitment but treating similar patients, comparing their sociodemographic characteristics and the proportions of those in each group agreeing with each statement. Results: There was a response rate of 96% (75/78). Findings showed that, during trial recruitment and before the RCT results were known, the majority of all responding clinicians (73.3%) considered Y-CMAP to be an effective treatment for young people at risk of self-harm or suicide. Although there was an acknowledgement of individual preferences for the intervention, there was near consensus (90%) on the need to conduct an RCT for reaching an evidence-based decision. However, there were no significant differences in the proportion of recruiting clinicians reporting a treatment preference for Y-CMAP than non-recruiting clinicians (31 (88.6%) versus 36 (90%), p = 0.566). A significantly higher proportion of non-recruiting clinicians (87.5%) as compared to (48.5%) in the trial (p = 0.000) stated that there may be other treatments that may be equally good for the patients, seemingly undermining a preference for the intervention. Those reporting a treatment preference also acknowledged that there was nothing on which this preference was based, however confident they felt about them, thus accepting clinical equipoise as ethical justification for conducting the RCT. There was a significant group difference in views that treatment overall is better as a result of young patients’ participation in the Y-CMAP trial (p = 0.015) (i.e. more clinicians not involved in the trial agreed with this statement). Similarly, more clinicians not involved in the trial agreed on the perceived availability of other treatment options that were good for young people at risk of self-harm (p < 0.05). Conclusions: The paper highlights that clinicians in Pakistan accept the notion of clinical equipoise as an ethical justification for patient participation in RCTs. The need for conducting RCTs to generate evidence base and to reduce bias was considered important by the clinical community

Division I College Athletes’ Self-Perception: Investigating the Impact of Race and Discrimination

Self-perception is the level of competency at which individuals evaluate themselves in certain areas or domains (Marsh & Shavelson, 1985). An individual’s self-perceptions contribute to their global self-worth and even predicts performance (Cuellar, 2014; Harter & Neemann, 2012). This study measures self-perception scores, as well as experiences with racial discrimination, of 306 NCAA Division I college athletes using the Self-Perception Profile for College Students (Harter & Neemann, 2012). Scores are compared across race. Findings suggest that White college athletes have significantly higher self-perception scores than college athletes of color - with recent discrimination (within the last year) as a significant predictor of multiple areas of self-perception. The implications of this study suggest that faculty and other campus stakeholders should pursue positive relationships with the college athletes they encounter. Positive relationships between college athletes and faculty may help raise college athlete self-perceptions, and in turn, performance in a variety of areas

A Microfluidic Co-Flow Route for Human Serum Albumin-Drug-Nanoparticle Assembly.

Nanoparticles are widely studied as carrier vehicles in biological systems because their size readily allows access through cellular membranes. Moreover, they have the potential to carry cargo molecules and as such, these factors make them especially attractive for intravenous drug delivery purposes. Interest in protein-based nanoparticles has recently gained attraction due to particle biocompatibility and lack of toxicity. However, the production of homogeneous protein nanoparticles with high encapsulation efficiencies, without the need for additional cross-linking or further engineering of the molecule, remains challenging. Herein, we present a microfluidic 3D co-flow device to generate human serum albumin/celastrol nanoparticles by co-flowing an aqueous protein solution with celastrol in ethanol. This microscale co-flow method resulted in the formation of nanoparticles with a homogeneous size distribution and an average size, which could be tuned from ≈100 nm to 1 μm by modulating the flow rates used. We show that the high stability of the particles stems from the covalent cross-linking of the naturally present cysteine residues within the particles formed during the assembly step. By choosing optimal flow rates during synthesis an encapsulation efficiency of 75±24 % was achieved. Finally, we show that this approach achieves significantly enhanced solubility of celastrol in the aqueous phase and, crucially, reduced cellular toxicity

BMP signalling regulates the pre-implantation development of extra-embryonic cell lineages in the mouse embryo.

Pre-implantation development requires the specification and organization of embryonic and extra-embryonic lineages. The separation of these lineages takes place when asymmetric divisions generate inside and outside cells that differ in polarity, position and fate. Here we assess the global transcriptional identities of these precursor cells to gain insight into the molecular mechanisms regulating lineage segregation. Unexpectedly, this reveals that complementary components of the bone morphogenetic protein (BMP) signalling pathway are already differentially expressed after the first wave of asymmetric divisions. We investigate the role of BMP signalling by expressing dominant negative forms of Smad4 and Bmpr2, by downregulating the pathway using RNA interference against BMP ligands and by applying three different BMP inhibitors at distinct stages. This reveals that BMP signalling regulates the correct development of both extra-embryonic lineages, primitive endoderm and trophectoderm, but not the embryonic lineage, before implantation. Together, these findings indicate multiple roles of BMP signalling in the early mouse embryo.This work was supported by a Wellcome Trust programme grant to MZG and an Agency for Science, Technology and Research (A*Star) core research budget to PR.This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/ncomms666

A longitudinal, qualitative study exploring sustained adherence to a hand exercise programme for rheumatoid arthritis evaluated in the SARAH trial

This study explores the experience of participants taking part in a hand exercise programme for people with rheumatoid arthritis with a focus on adherence. The exercise programme was tested in a randomised controlled trial. This parallel qualitative study will inform future implementation into clinical practice.Twenty-seven semi-structured interviews from 14 participants were undertaken at two time points (4 and 12 months after randomisation). We collected data of participants' experiences over time. This was guided by an interview schedule. Interview data were analysed using interpretative phenomenological analysis which is informed by phenomenological and hermeneutic theory. We recruited participants from National Health Service rheumatology and therapy departments.At 4 months, 11/14 participants reported continuing with the exercises. By 12 months, 7/13 participants still reported exercising. The ability to establish a routine determined whether participants adhered to the exercise programme. This was sometimes influenced by practical issues. We also identified facilitators and barriers to regular exercise in the themes of the following: the therapeutic encounter, perceived benefit of exercises, attitude of mind, confidence, and unpredictability.Establishing a routine was an important step towards participants being able to exercise independently. Therapists provided participants with skills to continue to exercise while dealing with changes in symptoms and schedules. Potential barriers to long-term exercise adherence need to be taken into account and addressed for successful implementation of this programme. Implications for Rehabilitation Behavioural change components such as the use of an exercise planner (stating intentions of where, when and how), daily diary sheets, and joint goal setting enhance adherence to a hand exercise programme for RA by helping to establish routines. Exercise routines need to be flexible enough to fit in with life and symptom changes whilst delivering a sufficient dosage. Therapists facilitate this process by using behavioural components alongside more commonly used aspects of care (assessment, education, advice, and encouragement) to enable people with RA to become independent exercisers

An ethics of anthropology-informed community engagement with COVID-19 clinical trials in Africa

The COVID-19 pandemic has reinforced the critical role of ethics and community engagement in designing and conducting clinical research during infectious disease outbreaks where no vaccine or treatment already exists. In reviewing current practices across Africa, we distinguish between three distinct roles for community engagement in clinical research that are often conflated: 1) the importance of community engagement for identifying and honouring cultural sensitivities; 2) the importance of recognising the socio-political context in which the research is proposed; and 3) the importance of understanding what is in the interest of communities recruited to research according to their own views and values. By making these distinctions, we show that current practice of clinical research could draw on anthropology in ways which are sometimes unnecessary to solicit local cultural values, overlook the importance of socio-political contexts and wider societal structures within which it works, potentially serving to reinforce unjust political or social regimes, and threaten to cast doubt on the trustworthiness of the research. We argue that more discerning anthropological engagement as well as wider collaboration with other social scientists and those working in the humanities is urgently needed to improve the ethics of current biomedical and pharmaceutical research practice in Africa

Atom--Molecule Coherence in a Bose-Einstein Condensate

Coherent coupling between atoms and molecules in a Bose-Einstein condensate (BEC) has been observed. Oscillations between atomic and molecular states were excited by sudden changes in the magnetic field near a Feshbach resonance and persisted for many periods of the oscillation. The oscillation frequency was measured over a large range of magnetic fields and is in excellent quantitative agreement with the energy difference between the colliding atom threshold energy and the energy of the bound molecular state. This agreement indicates that we have created a quantum superposition of atoms and diatomic molecules, which are chemically different species.Comment: 7 pages, 6 figure

Motivations and barriers to prosthesis users participation in physical activity, exercise and sport : a review of the literature

The UK will host the Paralympics in 2012 and the Commonwealth Games in 2014 showcasing the talents of elite athletes and aiming to inspire the population to become involved. However, low levels of physical activity (PA) are prevalent: only 40% of men and 28% of women meet the minimum UK recommendations. The limb absent population is no exception. To determine if people with limb amputations are participating in physical activity and sport; whether post-amputation activity levels match pre-amputation levels; and if there are motivations and barriers to participation. Study design: Literature review Five reviewers systematically search of peer reviewed and gray literature in seven bibliographic databases and the Cochrane Library. Results: Following rigorous elimination, 12 articles were finally included in the review and critically appraised. Four themes were identified: components, rehabilitation outcomes, body image and motivations and barriers to participation. People with limb absence are not participating in PA conducive to health benefits, and only a minority participate in exercise and sports. Participation following amputation does not mirror that of pre-amputation levels, and more barriers than motivations exist to adopting and maintaining a physically active lifestyle. This literature review aims to inform those involved in rehabilitation and ongoing care of those with limb absence about what motivates or precludes their participation in physical activity, exercise and sport. Such knowledge could be applied to improving health and well being in this population