Purpose
Despite the high incidence of falls in patients with OA, few studies have explored whether falls risk is affected after patients undergo total knee arthroplasty (TKA). Therefore, the aim of ...this systematic review was to identify the extent of the effects of TKA on balance and incidence of falls by critically reviewing the available literature.
Methods
A systematic review of published literature sources was conducted up to March 2014. All studies assessing balance and incidence of falls after TKA (without physiotherapeutic intervention) were included. The methodological quality of each study was reviewed using the Critical Appraisal Skill Programme tool.
Results
Thirteen studies were included, comprising of ten cohort studies (Level II) and three studies with Level of evidence III.
Conclusions
Findings provide evidence that TKA improves significantly single-limb standing balance (~60%) and dynamic balance up to 1-year following surgery (Level of evidence II). Moreover, TKA influences positively fear of falling and incidence of falls by switching 54.2 % of pre-operative fallers to post-operative non-fallers (Level of evidence II–III). It is highlighted that knee extension strength, proprioception and symmetrization of postural strategies have not fully recovered post-TKA and influence balance performance. Clinically, these persistent deficits need to be mitigated by physiotherapy even before TKA takes place.
Initial results are presented from 3D MHD modelling of stellar-wind bubbles around O stars moving supersonically through the ISM. We describe algorithm updates that enable high-resolution 3D MHD ...simulations at reasonable computational cost. We apply the methods to the simulation of the astrosphere of a rotating massive star moving with 30km s−1 through the diffuse interstellar medium, for two different stellar magnetic field strengths, 10G and 100G. Features in the flow are described and compared with similar models for the Heliosphere. The shocked interstellar medium becomes asymmetric with the inclusion of a magnetic field misaligned with the star's direction of motion, with observable consequences. When the Alfv´enic Mach number of the wind is ≤ 10 then the stellar magnetic field begins to affect the structure of the wind bubble and features related to the magnetic axis of the star become visible at parsec scales. Prospects for predicting and measuring non-thermal radiation are discussed.
Abstract Objectives Total knee replacement (TKR) has a beneficial effect on patients’ functional ability; however, incidence of falls and deficits on proprioception are not restored even 1-year after ...surgery. Early and intensive exercise post-TKR has received limited endorsement in the literature. The aim of this review was to systemically identify and critically appraise clinical studies investigating the effect of sensori-motor training on functional and balance performance in TKR patients. Data sources The electronic databases Cochrane Library, MEDLINE, EMBASE, CINAHL, PEDro and the register of current controlled trials were searched up to September 2014. Review methods Two independent reviewers used predefined inclusion and exclusion criteria to identify all eligible articles. Eligible articles were summarized and critically reviewed, using the PEDro scale. Results Two hundred and seventy six articles were screened, six were included. The studies, presented the results of 409 patients (269 intervention, 140 control). A range of rehabilitation protocols were defined by components of proprioception, postural control, balance perturbation and coordination. All studies supported the use of sensori-motor training as an additional element in patients’ rehabilitation protocols. Clinical performance-based tests (more than relevant patient-reported measures) showed that functional ability and balance were improved compared to controls. The robustness of evidence was compromised because most of the studies were underpowered. Conclusions Limited robust (Ia) evidence supports the equal effectiveness of functional rehabilitation program as a functional rehabilitation enhanced with sensori-motor elements in patients post-TKR. However, dose-response parameters of exercise eliciting improvement warrant further investigation.
Context.
In recent years, winds from massive stars have been considered promising sites for investigating relativistic particle acceleration. In particular, the resulting bow-shaped shocks from the ...interaction of the supersonic winds of runaway stars with interstellar matter have been intensively observed at many different wavelengths, from radio to
γ
-rays.
Aims.
In this study we investigate the O4If star, BD+43° 3654, the bow shock of which is, so far, the only one proven to radiate both thermal and non-thermal emission at radio frequencies. In addition, we consider NGC 7635, the Bubble Nebula, as a bow shock candidate and examine its apex for indications of thermal and non-thermal radio emission.
Methods.
We observed both bow shocks in radio frequencies with the Very Large Array (VLA) in the C and X bands (4–8 GHz and 8–12 GHz) and with the Effelsberg telescope at 4–8 GHz. We analysed single-dish and interferometric results individually, in addition to their combined emission, obtained spectral index maps for each source, and calculated their spectral energy distributions.
Results.
We find that both sources emit non-thermal emission in the radio regime, with the clearest evidence for NGC 7635, whose radio emission has a strongly negative spectral index along the northern rim of the bubble. We present the first high-resolution maps of radio emission from NGC 7635, finding that the morphology closely follows the optical nebular emission. Our results are less conclusive for the bow shock of BD+43° 3654, as its emission becomes weaker and faint at higher frequencies in VLA data. Effelsberg data show a much larger emitting region (albeit a region of thermal emission) than is detected with the VLA for this source.
Conclusions.
Our results extend the previous radio results from the BD+43° 3654 bow shock to higher frequencies, and with our NGC 7635 results we double the number of bow shocks around O stars with detected non-thermal emission, from one to two. Modelling of the multi-wavelength data for both sources shows that accelerated electrons at the wind termination shock are a plausible source for the non-thermal radio emission, but energetics arguments suggest that any non-thermal X-ray and
γ
-ray emission could be significantly below existing upper limits. Enhanced synchrotron emission from compressed galactic cosmic rays in the radiative bow shock could also explain the radio emission from the BD+43° 3654 bow shock, but not from NGC 7635. The non-detection of point-like radio emission from BD+43° 3654 puts an upper limit on the mass-loss rate of the star that is lower than values quoted in the literature.
To assess how inadequate reporting of cointerventions influences estimated treatment effects in recent cardiovascular trials.
Medline/Embase were systematically searched from January 1, 2011 to July ...1, 2021 for trials evaluating pharmacologic interventions on clinical cardiovascular outcomes published in 5 high-impact journals. Information on adequate vs inadequate reporting of cointerventions, blinding, risk of bias due to deviations of intended interventions (low vs high/some concerns), funding (nonindustry vs industry), design (superiority vs noninferiority), and results were assessed by 2 reviewers. The association with effect sizes was assessed using meta-regression random-effect analysis, expressed as ratios of odds ratios (ROR). RORs of >1.0 indicated that trials with the methodological factor pointing to lower quality report larger treatment estimates.
In total, 164 trials were included. Of the 164 trials, 124 (74%) did not adequately report cointerventions; 89 of the 164 trials (54%) provided no information regarding cointerventions, and 70 of the 164 (43%) were at risk of bias due to inadequate blinding. Moreover, 86 of the 164 (53%) were at risk of bias due to deviation of intended interventions. Of the 164 trials, 144 (88%) were funded by the industries. Trials with inadequate reporting of cointerventions had larger treatment estimates for the primary end point (ROR, 1.08; 95% CI, 1.01-1.15; I2=0%). No significant association with results for blinding (ROR, 0.97; 95% CI, 0.91-1.03; I2=66%), deviation of intended interventions (ROR, 0.98; 95% CI, 0.92-1.04; I2=0%), or funding (ROR, 1.01; 95% CI, 0.93-1.09; I2=0%) was found.
We conclude that trials with inadequate reporting of cointerventions showed larger treatment effect estimates, potentially indicating overestimation of therapeutic benefit.
Prospero Identifier: CRD42017072522
The nearby, massive, runaway star Zeta Ophiuchi has a large bow shock detected in optical and infrared, and, uniquely among runaway O stars, diffuse X-ray emission is detected from the shocked ...stellar wind. Here we make the first detailed computational investigation of the bow shock of Zeta Ophiuchi, to test whether a simple model of the bow shock can explain the observed nebula, and to compare the detected X-ray emission with simulated emission maps. We re-analysed archival {\it Chandra} observations of the thermal diffuse X-ray emission from the shocked wind region of the bow shock, finding total unabsorbed X-ray flux (0.3-2 keV band) corresponding to a diffuse luminosity of \(L_\mathrm{X}=2.33~(0.79-3.45)\times10^{29}\)ergs\(^{-1}\). 3D MHD simulations were used to model the interaction of the star's wind with a uniform ISM using a range of stellar and ISM parameters motivated by observational constraints. Synthetic infrared, Ha, soft X-ray, emission measure, and radio 6\,GHz emission maps were generated from three simulations, for comparison with relevant observations. Simulations where the space velocity of Zeta Ophiuchi has a significant radial velocity produce infrared emission maps with opening angle of the bow shock in better agreement with observations than for the case where motion is fully in the plane of the sky. The simulation with the highest pressure has the closest match, with flux level within a factor of 2 of the observational lower limit, and emission weighted temperature of \(\log_{10}(T_\mathrm{A}/\mathrm{K})=6.4\), although the morphology of the diffuse emission appears somewhat different. Observed X-ray emission is a filled bubble brightest near the star whereas simulations predict brightening towards the contact discontinuity as density increases.
Winds from massive stars have recently been deemed promising sites for investigating relativistic particle acceleration. Particularly, the resulting bow shock from the interaction of the winds of ...runaway stars with interstellar matter has been observed at multiple wavelengths. Here we investigate the O4If star, BD+433654, the bow shock of which is, so far, the only one proven to radiate both thermally and non-thermally at radio frequencies. We also consider NGC7635 as a bow shock candidate and examine its apex for indications of thermal and non-thermal radio emission. We observed both sources with the VLA at 4-8 GHz and 8-12 GHz, and with the Effelsberg telescope at 4-8 GHz. We analysed data from both telescopes individually and combined, obtained their spectral index maps and calculated their Spectral Energy Distributions. We present the first high-resolution maps of radio emission from NGC7635. We find that both emit non-thermal emission in the radio regime, with the clearest evidence for NGC7635. Our results are less conclusive for BD+433654, as the emission from its bow shock becomes weaker and fainter at higher radio frequencies. Our results extend the previous radio results for the BD+433654 bow shock to higher frequencies. Modelling of our data for both sources shows that accelerated electrons at the wind termination shock are a plausible source for the non-thermal radio emission, but energetics arguments suggest that any non-thermal X-ray and \(\gamma\)-ray emission could be significantly below existing upper limits. Enhanced synchrotron emission from compressed Galactic cosmic rays in the radiative bow shock could also explain the radio emission from the BD+433654 bow shock but not NGC7635. Non-detection of point-like radio emission from BD+433654 puts an upper limit on the mass-loss rate of the star that is lower than values quoted in the literature. abridged
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