2,784 research outputs found

    The influence of the strength of bone on the deformation of acetabular shells : a laboratory experiment in cadavers

    Get PDF
    Date of Acceptance: 24/08/2014 Ā©2015 The British Editorial Society of Bone & Joint Surgery. The authors would like to thank N. Taylor (3D Measurement Company) for his work with regard to data acquisition and processing of experimental data. We would also like to thank Dr A. Blain of Newcastle University for performing the statistical analysis The research was supported by the NIHR Newcastle Biomedical Research Centre. The authors P. Dold, M. Flohr and R. Preuss are employed by Ceramtec GmbH. Martin Bone received a salary from the joint fund. The author or one or more of the authors have received or will receive benefits for personal or professional use from a commercial party related directly or indirectly to the subject of this article. This article was primary edited by G. Scott and first proof edited by J. Scott.Peer reviewedPostprin

    Polarization of macrophages toward M2 phenotype is favored by reduction in iPLA2Ī² (group VIA phospholipase A2)*

    Get PDF
    Macrophages are important in innate and adaptive immunity. Macrophage participation in inflammation or tissue repair is directed by various extracellular signals and mediated by multiple intracellular pathways. Activation of group VIA phospholipase A2 (iPLA2Ī²) causes accumulation of arachidonic acid, lysophospholipids, and eicosanoids that can promote inflammation and pathologic states. We examined the role of iPLA2Ī² in peritoneal macrophage immune function by comparing wild type (WT) and iPLA2Ī²āˆ’/āˆ’ mouse macrophages. Compared with WT, iPLA2Ī²āˆ’/āˆ’ macrophages exhibited reduced proinflammatory M1 markers when classically activated. In contrast, anti-inflammatory M2 markers were elevated under naĆÆve conditions and induced to higher levels by alternative activation in iPLA2Ī²āˆ’/āˆ’ macrophages compared with WT. Induction of eicosanoid (12-lipoxygenase (12-LO) and cyclooxygenase 2 (COX2))- and reactive oxygen species (NADPH oxidase 4 (NOX4))-generating enzymes by classical activation pathways was also blunted in iPLA2Ī²āˆ’/āˆ’ macrophages compared with WT. The effects of inhibitors of iPLA2Ī², COX2, or 12-LO to reduce M1 polarization were greater than those to enhance M2 polarization. Certain lipids (lysophosphatidylcholine, lysophosphatidic acid, and prostaglandin E2) recapitulated M1 phenotype in iPLA2Ī²āˆ’/āˆ’ macrophages, but none tested promoted M2 phenotype. These findings suggest that (a) lipids generated by iPLA2Ī² and subsequently oxidized by cyclooxygenase and 12-LO favor macrophage inflammatory M1 polarization, and (b) the absence of iPLA2Ī² promotes macrophage M2 polarization. Reducing macrophage iPLA2Ī² activity and thereby attenuating macrophage M1 polarization might cause a shift from an inflammatory to a recovery/repair milieu

    Difference in predictors and barriers to arts and cultural engagement with age in the United States: A cross-sectional analysis using the Health and Retirement Study

    Get PDF
    INTRODUCTION: Arts and cultural engagement are associated with a range of mental and physical health benefits, including promoting heathy aging and lower incidence of age-related disabilities such as slower cognitive decline and slower progression of frailty. This suggests arts engagement constitutes health-promoting behaviour in older age. However, there are no large-scale studies examining how the predictors of arts engagement vary with age. METHODS: Data from the Health and Retirement Study (2014) were used to identify sociodemographic, life satisfaction, social, and arts appreciation predictors of (1) frequency of arts engagement, (2) cultural attendance, (3) difficulty participating in the arts, and (4) being an interested non-attendee of cultural events. Logistic regression models were stratified by age groups [50-59, 60-69, ā‰„70] for the frequency of arts participation outcome and [50-69 vs ā‰„70] all other outcomes. RESULTS: Findings indicated a number of age-related predictors of frequent arts engagement, including gender, educational attainment, wealth, dissatisfaction with aging, and instrumental activities of daily living (iADL). For cultural event attendance, lower interest in the arts predicted lack of engagement across age groups, whereas higher educational attainment and more frequent religious service attendance became predictors in older age groups (ā‰„ 70). Adults in both age groups were less likely to report difficulties engaging in the arts if they had lower neighbourhood safety, whilst poor self-rated health and low arts appreciation also predicted reduced likelihood of this outcome, but only in the younger (50-69) age group. Adults in the older (ā‰„ 70) age group were more likely to be interested non-attendees of cultural events if they had higher educational attainment and less likely if they lived in neighbourhoods with low levels of safety. CONCLUSIONS: Our results suggest that certain factors become stronger predictors of arts and cultural engagement and barriers to engagement as people age. Further, there appear to be socioeconomic inequalities in engagement that may increase in older ages, with arts activities overall more accessible as individuals age compared to cultural engagement due to additional financial barriers and transportation barriers. Ensuring that these activities are accessible to people of all ages will allow older adults to benefit from the range of health outcomes gained from arts and cultural engagement

    Sickness absence after carpal tunnel release : a systematic review of the literature

    Get PDF
    Funding: LN was funded by an NIHR Doctoral Research Fellowship (Ref: DRF-2015-08-056).Peer reviewe

    Planar charged-particle trajectories in multipole magnetic fields

    No full text
    International audienceThis paper provides a complete generalization of the classic result that the radius of curvature (?) of a charged-particle trajectory confined to the equatorial plane of a magnetic dipole is directly proportional to the cube of the particle's equatorial distance (?) from the dipole (i.e. ? ? ?3). Comparable results are derived for the radii of curvature of all possible planar charged-particle trajectories in an individual static magnetic multipole of arbitrary order m and degree n. Such trajectories arise wherever there exists a plane (or planes) such that the multipole magnetic field is locally perpendicular to this plane (or planes), everywhere apart from possibly at a set of magnetic neutral lines. Therefore planar trajectories exist in the equatorial plane of an axisymmetric (m = 0), or zonal, magnetic multipole, provided n is odd: the radius of curvature varies directly as ?n+2. This result reduces to the classic one in the case of a zonal magnetic dipole (n =1). Planar trajectories exist in 2m meridional planes in the case of the general tesseral (0 m n) magnetic multipole. These meridional planes are defined by the 2m roots of the equation cos[m(? ? ?nm)] = 0, where ?nm = (1/m) arctan (hnm/gnm); gnm and hnm denote the spherical harmonic coefficients. Equatorial planar trajectories also exist if (n ? m) is odd. The polar axis (? = 0,?) of a tesseral magnetic multipole is a magnetic neutral line if m > 1. A further 2m(n ? m) neutral lines exist at the intersections of the 2m meridional planes with the (n ? m) cones defined by the (n ? m) roots of the equation Pnm(cos ?) = 0 in the range 0 ? ?, where Pnm(cos ?) denotes the associated Legendre function. If (n ? m) is odd, one of these cones coincides with the equator and the magnetic field is then perpendicular to the equator everywhere apart from the 2m equatorial neutral lines. The radius of curvature of an equatorial trajectory is directly proportional to ?n+2 and inversely proportional to cos[m(? ? ?nm)]. Since this last expression vanishes at the 2m equatorial neutral lines, the radius of curvature becomes infinitely large as the particle approaches any one of these neutral lines. The radius of curvature of a meridional trajectory is directly proportional to rn+2, where r denotes radial distance from the multipole, and inversely proportional to Pnm(cos ?)/sin θ. Hence the radius of curvature becomes infinitely large if the particle approaches the polar magnetic neutral line (m > 1) or any one of the 2m(n ? m) neutral lines located at the intersections of the 2m meridional planes with the (n ? m) cones. Illustrative particle trajectories, derived by stepwise numerical integration of the exact equations of particle motion, are presented for low-degree (n ? 3) magnetic multipoles. These computed particle trajectories clearly demonstrate the "non-adiabatic'' scattering of charged particles at magnetic neutral lines. Brief comments are made on the different regions of phase space defined by regular and irregular trajectories

    Optical structure and function of the white filamentary hair covering the edelweiss bracts

    Full text link
    The optical properties of the inflorescence of the high-altitude ''Leontopodium nivale'' subsp. ''alpinum'' (edelweiss) is investigated, in relation with its submicrometer structure, as determined by scanning electron microscopy. The filaments forming the hair layer have been found to exhibit an internal structure which may be one of the few examples of a photonic structure found in a plant. Measurements of light transmission through a self-supported layer of hair pads taken from the bracts supports the idea that the wooly layer covering the plant absorbs near-ultraviolet radiation before it reaches the cellular tissue. Calculations based on a photonic-crystal model provides insight on the way radiation can be absorbed by the filamentary threads.Comment: 9 pages, 13 figures. Published pape

    Factors associated with unvaccinated caregivers who plan to vaccinate their children

    Full text link
    Vaccine hesitancy is complex and a threat to global public health during the ongoing COVID-19 pandemic. Our objective was to determine factors associated with caregivers' willingness to vaccinate children despite not being immunized themselves against COVID-19. The International COVID-19 Parental Attitude Study (COVIPAS), a multinational cohort study, recruited caregivers of children 0-18 years old in 21 Emergency Departments (EDs) in USA, Canada, Israel, and Switzerland during November-December 2021. Of a total of 4536 caregivers who completed the survey, 882 (19.4%) were unvaccinated, and 62 (7.0%) of the unvaccinated planned to vaccinate their children. Unvaccinated caregivers with children that had their childhood vaccines up-to-date (OR 3.03 (1.36, 8.09), p = 0.01), and those very worried their child has COVID-19 in the ED (OR 3.11 (1.44, 6.34), p < 0.01) were much more likely to plan to immunize their children. Primary care providers and public health agencies should not assume that unvaccinated parents will not vaccinate their children. Determining child's vaccination status and parental level of concern about COVID-19 may help identify caregivers who are open to give their children the vaccine. Keywords: COVID-19; Sars-cov-2; Unvaccinated; Vaccination; Vaccine hesitancy

    Sharks of the order Carcharhiniformes from the British Coniacian, Santonian and Campanian (Upper Cretaceous).

    Get PDF
    Bulk sampling of phosphate-rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi (Herman, 1977) comb. nov., Crassescyliorhinus germanicus (Herman, 1982) gen. nov., Scyliorhinus elongatus (Davis, 1887), Scyliorhinus brumarivulensis sp. nov., ? Palaeoscyllium sp., Prohaploblepharus riegrafi (MĆ¼ller, 1989) gen. nov., ? Cretascyliorhinus sp., Scyliorhinidae inc. sedis 1, Scyliorhinidae inc. sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977, Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ? Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae, and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed

    Return to work after carpal tunnel release surgery: a qualitative interview study

    Get PDF
    Background Carpal tunnel syndrome is a common nerve compression disorder which affects hand sensation and function. Carpal tunnel release surgery (CTR) is frequently performed to alleviate these symptoms. For many CTR patients, surgery occurs during their working lifetime, but there is currently no evidence-based guidance to inform clinicians or patients when it might be safe to return to different types of work afterwards. The aim of this qualitative study was to explore the return to work experiences of patients who had recently undergone CTR. Methods Semi-structured 1:1 interviews were conducted with a subgroup of participants recruited to a multi-centre prospective cohort study. Interviewees were purposely selected to represent a range of demographic, clinical and occupational characteristics. All had recently undergone CTR and had returned to work. Interviews were audio recorded, transcribed verbatim and analysed using the framework method. Participants were recruited until data saturation was achieved. Results Fourteen participants were interviewed: 11 women (median age 49ā€‰years, range 27ā€“61) and 3 men (age range 51ā€“68ā€‰years). Three key themes were identified. Theme 1 centred on the level of functional disability experienced immediately after surgery. There was an expectation that CTR would be a ā€˜minorā€™ procedure, but this did not match the participantsā€™ experiences. Theme 2 explored the desire for validation for the time away from work, with participants recalling a need to justify their work absence to themselves as well as to their employers. Theme 3 focused on the participantsā€™ reflections of handing their return to work and function, with many reporting uncertainties about what constituted appropriate activity loads and durations. There was a desire for specific information relating to individual work roles. Conclusion Individual return to work decision-making was largely influenced by the recommendations received. According to the views of participants, clinicians may be able to prepare patients better pre-operatively, especially with respect to function in the immediate post-operative period and by providing return to work guidance that can be tailored for individual work roles
    • ā€¦
    corecore