1,307 research outputs found

    Novel, bilateral, two-bellied muscles span the extensor forearm, thenar eminence to insert on the proximal phalanx of the thumb: clinical and embryological significance

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    Muscle and tendon variations in the forearm, wrist and hand are commonly reported in the anatomical and surgical literature. They are frequently the source of inflammatory conditions such as de Quervain’s tenosynovitis or carpal tunnel syndrome. During academic dissection, a cadaver presented with bilateral, additional muscles running parallel to the abductor pollicis longus muscles (APL) in the extensor compartment of the forearm. Both additional muscles had two bellies, one proximal and one distal, with an intervening tendon. The proximal bellies were separate and distinct from the adjacent APLs. The tendons traversed the first dorsal compartments with the tendons of the APLs and the extensor pollicis brevis muscles (EPB). The distal bellies lay adjacent to the abductor pollicis brevis (APB) muscles in the thenar compartments, and inserted onto the volar base of the proximal phalanges of the thumbs. Following a thorough search of the literature, we determined that these additional muscles constitute a previously unreported variation. This report details the variation, compares it with other reported variations, presents the related embryology, and reviews the significance of this variation as it relates to inflammatory conditions and surgical procedures

    Rapid physiological and transcriptomic changes associated with oxygen delivery in larval anemonefish suggest a role in adaptation to life on hypoxic coral reefs

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    Connectivity of coral reef fish populations relies on successful dispersal of a pelagic larval phase. Pelagic larvae must exhibit high swimming abilities to overcome ocean and reef currents, but once settling onto the reef, larvae transition to endure habitats that become hypoxic at night. Therefore, coral reef fish larvae must rapidly and dramatically shift their physiology over a short period of time. Taking an integrative, physiological approach, using swimming respirometry, and examining hypoxia tolerance and transcriptomics, we show that larvae of cinnamon anemonefish (Amphiprion melanopus) rapidly transition between "physiological extremes" at the end of their larval phase. Daily measurements of swimming larval anemonefish over their entire early development show that they initially have very high mass-specific oxygen uptake rates. However, oxygen uptake rates decrease midway through the larval phase. This occurs in conjunction with a switch in haemoglobin gene expression and increased expression of myoglobin, cytoglobin, and neuroglobin, which may all contribute to the observed increase in hypoxia tolerance. Our findings indicate that critical ontogenetic changes in the gene expression of oxygen-binding proteins may underpin the physiological mechanisms needed for successful larval recruitment to reefs

    A mixed-methods feasibility study of a comorbidity-adapted exercise program for low back pain in older adults (COMEBACK):a protocol

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    BACKGROUND: The prevalence of low back pain increases with age and has a profound impact on physical and psychosocial health. With increasing age comes increasing comorbidity, and this also has pronounced health consequences. Whilst exercise is beneficial for a range of health conditions, trials of exercise for low back pain management often exclude older adults. It is currently unknown whether an exercise program for older adults with low back pain, tailored for the presence of comorbidities, is acceptable for participants and primary healthcare providers (PHCPs). Therefore, this mixed-methods study will assess the feasibility of an 8-week comorbidity-adapted exercise program for older people with low back pain and comorbid conditions. METHODS: The 3-phased feasibility study will be performed in a primary healthcare setting. PHCPs will be trained to deliver a comorbidity-adapted exercise program for older people with low back pain and comorbidities. Healthcare-seeking adults > 65 will be screened for eligibility over telephone, with a recruitment target of 24 participants. Eligible participants will attend an initial appointment (diagnostic phase). During this initial appointment, a research assistant will collect patient demographics, self-reported outcome measurement data, and perform a physical and functional examination to determine contraindications and restrictions to an exercise program. During the development phase, PHCPs will adapt the exercise program to the individual and provide patient education. During the intervention phase, there will be two supervised exercise sessions per week, over 8 weeks (total of 16 exercise sessions). Each exercise session will be approximately 60 min in duration. A qualitative evaluation after the last exercise program session will explore the feasibility of the exercise program for participants and PHCPs. Progression criteria will determine the suitability for a fully powered randomised controlled trial. DISCUSSION: This mixed-methods feasibility study will assess an exercise program for older adults with low back pain and comorbidities. Once assessed for feasibility, the exercise program may be tested for effectiveness in a larger, fully powered randomised controlled trial. This information will add to the sparse evidence base on appropriate options for managing back pain in older adults. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry registration number: ACTRN12621000379819p (06/04/2021; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12621000379819p). TRIAL SPONSOR: Macquarie University, Department of Chiropractic, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40814-022-01097-x

    COVID-19: how has a global pandemic changed manual therapy technique education in chiropractic programs around the world?

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    Background Manual therapy is a cornerstone of chiropractic education, whereby students work towards a level of skill and expertise that is regarded as competent to work within the field of chiropractic. Due to the COVID-19 pandemic, chiropractic programs in every region around the world had to make rapid changes to the delivery of manual therapy technique education, however what those changes looked like was unknown. Aims The aims of this study were to describe the immediate actions made by chiropractic programs to deliver education for manual therapy techniques and to summarise the experience of academics who teach manual therapy techniques during the initial outbreak of COVID-19 pandemic. Methods A qualitative descriptive approach was used to describe the immediate actions made by chiropractic programs to deliver manual therapy technique education during the COVID-19 pandemic. Chiropractic programs were identified from the webpages of the Councils on Chiropractic Education International and the Council on Chiropractic Education – USA. Between May and June 2020, a convenience sample of academics who lead or teach in manual therapy technique in those programs were invited via email to participate in an online survey with open-ended questions. Responses were entered into the NVivo software program and analysed using a reflexive thematic analysis by a qualitative researcher independent to the data collection. Results Data from 16 academics in 13 separate chiropractic programs revealed five, interconnected themes: Immediate response; Move to online delivery; Impact on learning and teaching; Additional challenges faced by educators; and Ongoing challenges post lockdown. Conclusion This study used a qualitative descriptive approach to describe how some chiropractic programs immediately responded to the initial outbreak of the COVID-19 pandemic in their teaching of manual therapy techniques. Chiropractic programs around the world provided their students with rapid, innovative learning strategies, in an attempt to maintain high standards of chiropractic education; however, challenges included maintaining student engagement in an online teaching environment, psychomotor skills acquisition and staff workload

    Measurement of the transverse target and beam-target asymmetries in η\eta meson photoproduction at MAMI

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    We present new data for the transverse target asymmetry T and the very first data for the beam-target asymmetry F in the γpηp\vec \gamma \vec p\to\eta p reaction up to a center-of-mass energy of W=1.9 GeV. The data were obtained with the Crystal-Ball/TAPS detector setup at the Glasgow tagged photon facility of the Mainz Microtron MAMI. All existing model predictions fail to reproduce the new data indicating a significant impact on our understanding of the underlying dynamics of η\eta meson photoproduction. The peculiar nodal structure observed in existing T data close to threshold is not confirmed.Comment: 5 pages, 3 figures, accepted for publication in PR

    T and F asymmetries in π0 photoproduction on the proton

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    The γp→π0p reaction was studied at laboratory photon energies from 425 to 1445 MeV with a transversely polarized target and a longitudinally polarized beam. The beam-target asymmetry F was measured for the first time and new high precision data for the target asymmetry T were obtained. The experiment was performed at the photon tagging facility of the Mainz Microtron (MAMI) using the Crystal Ball and TAPS photon spectrometers. The polarized cross sections were expanded in terms of associated Legendre functions and compared to recent predictions from several partial-wave analyses. The impact of the new data on our understanding of the underlying partial-wave amplitudes and baryon resonance contributions is discussed

    Neutron skin of 208^{208}Pb from Coherent Pion Photoproduction

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    Information on the size and shape of the neutron skin on 208^{208}Pb has been extracted from coherent pion photoproduction cross sections measured using the Crystal Ball together with the Glasgow tagger at the MAMI electron beam facility. On exploitation of an interpolated fit of a theoretical model to the measured cross sections the half-height radius and diffuseness of the neutron distribution are found to be 6.70±0.03(stat)\pm 0.03(stat) fm and 0.55±0.01(stat)\pm 0.01(stat)0.03+0.02(sys)^{+0.02}_{-0.03}(sys) fm respectively, corresponding to a neutron skin thickness Δrnp\Delta r_{np}=0.15±0.03(stat)\pm 0.03(stat)0.03+0.01(sys)^{+0.01}_{-0.03}(sys) fm. The results give the first successful extraction of a neutron skin with an electromagnetic probe and indicate the skin of 208^{208}Pb has a halo character. The measurement provides valuable new constraints on both the structure of nuclei and the equation of state for neutron-rich matter.Comment: 4 figures 5 pages. Version submitted to journal. Includes additional studies of systematic effects in the extracted diffuseness, which led to a small increase in the quoted systematic error. These additional studies are discussed in the revised manuscript. Also includes minor editorial improvements to the tex

    Photoproduction of π0\pi^0-pairs off protons and off neutrons

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    Total cross sections, angular distributions, and invariant-mass distributions have been measured for the photoproduction of π0π0\pi^0\pi^0 pairs off free protons and off nucleons bound in the deuteron. The experiments were performed at the MAMI accelerator facility in Mainz using the Glasgow photon tagging spectrometer and the Crystal Ball/TAPS detector. The accelerator delivered electron beams of 1508 and 1557~MeV, which produced bremsstrahlung in thin radiator foils. The tagged photon beam covered energies up to 1400~MeV. The data from the free proton target are in good agreement with previous measurements and were only used to test the analysis procedures. The results for differential cross sections (angular distributions and invariant-mass distributions) for free and quasi-free protons are almost identical in shape, but differ in absolute magnitude up to 15\%. Thus, moderate final-state interaction effects are present. The data for quasi-free neutrons are similar to the proton data in the second resonance region (final state invariant masses up to \approx1550~MeV), where both reactions are dominated by the N(1520)3/2Δ(1232)3/2+πN(1520)3/2^-\rightarrow \Delta(1232)3/2^+\pi decay. At higher energies, angular and invariant-mass distributions are different. A simple analysis of the shapes of the invariant-mass distributions in the third resonance region is consistent with strong contributions of an NNσN^{\star}\rightarrow N\sigma decay for the proton, while the reaction is dominated by a sequential decay via a Δπ\Delta\pi intermediate state for the neutron. The data are compared to predictions from the Two-Pion-MAID model and the Bonn-Gatchina coupled channel analysis.Comment: accepted for publication in Eur. Phys. J.
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