1,594 research outputs found
The Latest Evidence with Regards to Femtosecond Laser-Assisted Cataract Surgery and Its Use Post 2020.
Femtosecond laser-assisted cataract surgery (FLACS) was introduced with the hope of making cataract surgery safer and making the refractive result more predictable. It is only in the last four years that level 1 prospective randomised controlled trials (RCT) using current technology have been published. These, along with a meta-analysis of recent studies have shown that there seems to be little long-term visual benefit when using FLACS with monofocal lenses. The promised decrease in ultrasound energy required to remove a cataract has not been consistently demonstrated. There is level one evidence that the rate of posterior capsular rupture is less with FLACS using modern software. The round capsulotomy may be of increasing importance with the uptake of toric, multifocal and extended depth of focus lenses where a predictable capsulotomy size and precise placement of the lens becomes more important
Distribution and correlates of plantar hyperkeratotic lesions in older people
<p>Abstract</p> <p>Background</p> <p>Plantar hyperkeratotic lesions are common in older people and are associated with pain, mobility impairment and functional limitations. However, little has been documented in relation to the frequency or distribution of these lesions. The aim of this study was to document the occurrence of plantar hyperkeratotic lesions and the patterns in which they occur in a random sample of older people.</p> <p>Methods</p> <p>A medical history questionnaire was administered to a random sample of 301 people living independently in the community (117 men, 184 women) aged between 70 and 95 years (mean 77.2, SD 4.9), who also underwent a clinical assessment of foot problems, including the documentation of plantar lesion locations, toe deformities and the presence and severity of hallux valgus.</p> <p>Results</p> <p>Of the 301 participants, 180 (60%) had at least one plantar hyperkeratotic lesion. Those with plantar lesions were more likely to be female (χ<sup>2 </sup>= 18.75, <it>p </it>< 0.01; OR = 2.86), have moderate to severe hallux valgus (χ<sup>2 </sup>= 6.15, <it>p </it>< 0.02; OR = 2.95), a larger dorsiflexion range of motion at the ankle (39.4 ± 9.3 <it>vs </it>36.3 ± 8.4°; <it>t </it>= 2.68, <it>df </it>= 286, <it>p </it>< 0.01), and spent more time on their feet at home (5.1 ± 1.0 <it>vs </it>4.8 ± 1.3 hours, <it>t </it>= -2.46, <it>df </it>= 299, <it>p </it>= 0.01). No associations were found between the presence of plantar lesions and body mass index, obesity, foot posture, dominant foot or forefoot pain. A total of 53 different lesions patterns were observed, with the most common lesion pattern being "roll-off" hyperkeratosis on the medial aspect of the 1<sup>st </sup>metatarsophalangeal joint (MPJ), accounting for 12% of all lesion patterns. "Roll-off" lesions under the 1<sup>st </sup>MPJ and interphalangeal joint were significantly associated with moderate to severe hallux valgus (<it>p </it>< 0.05), whereas lesions under the central MPJs were significantly associated with deformity of the corresponding lesser toe (<it>p </it>< 0.05). Factor analysis indicated that 62% of lesion patterns could be grouped under three broad categories, relating to medial, central and lateral locations.</p> <p>Conclusion</p> <p>Plantar hyperkeratotic lesions affect 60% of older people and are associated with female gender, hallux valgus, toe deformity, increased ankle flexibility and time spent on feet, but are not associated with obesity, limb dominance, forefoot pain or foot posture. Although there are a wide range of lesion distribution patterns, most can be classified into medial, central or lateral groups. Further research is required to determine whether these patterns are related to the dynamic function of the foot or other factors such as foot pathology or morphology.</p
Anomalous small angle x-ray scattering simulations: proof of concept for distance measurements for nanoparticle-labelled biomacromolecules in solution.
Anomalous small angle X-ray scattering can in principle be used to determine distances between metal label species on biological molecules. Previous experimental studies in the past were unable to distinguish the label-label scattering contribution from that of the molecule, because of the use of atomic labels; these labels contribute only a small proportion of the total scattering signal. However, with the development of nanocrystal labels (of 50-100 atoms) there is the possibility for a renewed attempt at applying anomalous small angle X-ray scattering for distance measurement. This is because the contribution to the scattered signal is necessarily considerably stronger than for atomic labels. Here we demonstrate through simulations, the feasibility of the technique to determine the end-to-end distances of labelled nucleic acid molecules as well as other internal distances mimicking a labelled DNA binding protein if the labels are dissimilar metal nanocrystals. Of crucial importance is the ratio of mass of the nanocrystals to that of the labelled macromolecule, as well as the level of statistical errors in the scattering intensity measurements. The mathematics behind the distance determination process is presented, along with a fitting routine than incorporates maximum entropy regularisation
Aerobic capacity, activity levels and daily energy expenditure in male and female adolescents of the kenyan nandi sub-group
The relative importance of genetic and socio-cultural influences contributing to the success of east Africans in endurance athletics remains unknown in part because the pre-training phenotype of this population remains incompletely assessed. Here cardiopulmonary fitness, physical activity levels, distance travelled to school and daily energy expenditure in 15 habitually active male (13.9±1.6 years) and 15 habitually active female (13.9±1.2) adolescents from a rural Nandi primary school are assessed. Aerobic capacity ([Formula: see text]) was evaluated during two maximal discontinuous incremental exercise tests; physical activity using accelerometry combined with a global positioning system; and energy expenditure using the doubly labelled water method. The [Formula: see text] of the male and female adolescents were 73.9±5.7 ml(.) kg(-1.) min(-1) and 61.5±6.3 ml(.) kg(-1.) min(-1), respectively. Total time spent in sedentary, light, moderate and vigorous physical activities per day was 406±63 min (50% of total monitored time), 244±56 min (30%), 75±18 min (9%) and 82±30 min (10%). Average total daily distance travelled to and from school was 7.5±3.0 km (0.8-13.4 km). Mean daily energy expenditure, activity-induced energy expenditure and physical activity level was 12.2±3.4 MJ(.) day(-1), 5.4±3.0 MJ(.) day(-1) and 2.2±0.6. 70.6% of the variation in [Formula: see text] was explained by sex (partial R(2) = 54.7%) and body mass index (partial R(2) = 15.9%). Energy expenditure and physical activity variables did not predict variation in [Formula: see text] once sex had been accounted for. The highly active and energy-demanding lifestyle of rural Kenyan adolescents may account for their exceptional aerobic fitness and collectively prime them for later training and athletic success
Embracing additive manufacture: implications for foot and ankle orthosis design
<p>Abstract</p> <p>Background</p> <p>The design of foot and ankle orthoses is currently limited by the methods used to fabricate the devices, particularly in terms of geometric freedom and potential to include innovative new features. Additive manufacturing (AM) technologies, where objects are constructed via a series of sub-millimetre layers of a substrate material, may present the opportunity to overcome these limitations and allow novel devices to be produced that are highly personalised for the individual, both in terms of fit and functionality.</p> <p>Two novel devices, a foot orthosis (FO) designed to include adjustable elements to relieve pressure at the metatarsal heads, and an ankle foot orthosis (AFO) designed to have adjustable stiffness levels in the sagittal plane, were developed and fabricated using AM. The devices were then tested on a healthy participant to determine if the intended biomechanical modes of action were achieved.</p> <p>Results</p> <p>The adjustable, pressure relieving FO was found to be able to significantly reduce pressure under the targeted metatarsal heads. The AFO was shown to have distinct effects on ankle kinematics which could be varied by adjusting the stiffness level of the device.</p> <p>Conclusions</p> <p>The results presented here demonstrate the potential design freedom made available by AM, and suggest that it may allow novel personalised orthotic devices to be produced which are beyond the current state of the art.</p
Effectiveness of direct-acting antiviral therapy among Aboriginal and Torres Strait Islander peoples with HCV infection in Australia: A national real-world cohort (REACH-C)
Aboriginal and Torres Strait Islander peoples experience a disproportionate burden of hepatitis C virus (HCV) infection. This study assessed the effectiveness of direct-acting antiviral (DAA) therapy among Aboriginal peoples in the three years following universal access in Australia. REACH-C, a national multicentre prospective cohort study, evaluated HCV treatment outcomes from sequential DAA initiations across 33 health services between March 2016 and June 2019. DAA effectiveness was assessed by sustained virological response (SVR) in the total (full analysis set) and effectiveness (modified analysis set excluding those lost to follow-up) populations. Overall, 915 (10%) Aboriginal and 8095 (90%) non-Indigenous people commenced DAA therapy, of whom 30% and 16% reported current injecting drug use and 73% and 42% were treated in primary care, respectively. SVR in the total and effectiveness populations was 74% and 94% among Aboriginal people and 82% and 94% among non-Indigenous people, with loss to follow-up contributing to lower SVR in the total population analysis (22% Aboriginal, 13% non-Indigenous). Among Aboriginal people, returning for follow-up was positively associated with older age (aOR 1.20; 95% CI 1.04, 1.39) and SVR was negatively associated with cirrhosis (aOR 0.39; 95% CI 0.19, 0.80) and prior DAA treatment (aOR 0.14; 95% CI 0.04, 0.49). Factors reflecting higher vulnerability or inequity were not associated with returning for testing or SVR. DAA therapy was highly effective among Aboriginal peoples with HCV treated through primary and tertiary services. Tailored community-led interventions are necessary to optimize follow-up and engagement. Sustained DAA uptake and equitable access to care, treatment and prevention are required for HCV elimination
Recommended from our members
Multicenter assessment of a hemoglobin A1c point-of-care device for diagnosis of diabetes mellitus.
ObjectiveA multisite investigation compared the analytical performance of a point-of-care (POC) HbA1c device with multiple commonly used HbA1c laboratory methods and an NGSP (National Glycohemoglobin Standardization Program) reference method.Research design and methodsThe Afinion AS100 POC device analyzed HbA1c using 618 EDTA whole blood excess patient specimens with clinically indicated HbA1c testing. Results were compared to measurements across five clinical laboratories and the NGSP reference method. Precision was evaluated over 8-10 consecutive days for low-, mid-, and high-range HbA1c specimens at all five sites.ResultsOver a wide range of HbA1c values (4.0%-15% HbA1c), 97.1% of the POC results and 94.5% of routine laboratory results fell within the target value of ±6% of the NGSP reference method results. The POC HbA1c results at 6.5% exhibited a total relative bias of -0.6% (-0.04% HbA1c) compared to the reference method while the aggregate of laboratory methods displayed a relative bias of -0.9% (-0.06% HbA1c). The total imprecision of the POC results ranged from 0.74-2.13% CV across the analytic measurement range compared to 0.81-3.23% CV for the routine laboratory methods.ConclusionsThe accuracy and precision of the Afinion POC HbA1c method was comparable to the laboratory HbA1c methods supporting the FDA's recent approval of the Afinion HbA1c Dx device for use in the diagnosis of diabetes
Molecular Valves for Controlling Gas Phase Transport Made from Discrete Angstrom-Sized Pores in Graphene
An ability to precisely regulate the quantity and location of molecular flux
is of value in applications such as nanoscale 3D printing, catalysis, and
sensor design. Barrier materials containing pores with molecular dimensions
have previously been used to manipulate molecular compositions in the gas
phase, but have so far been unable to offer controlled gas transport through
individual pores. Here, we show that gas flux through discrete angstrom-sized
pores in monolayer graphene can be detected and then controlled using
nanometer-sized gold clusters, which are formed on the surface of the graphene
and can migrate and partially block a pore. In samples without gold clusters,
we observe stochastic switching of the magnitude of the gas permeance, which we
attribute to molecular rearrangements of the pore. Our molecular valves could
be used, for example, to develop unique approaches to molecular synthesis that
are based on the controllable switching of a molecular gas flux, reminiscent of
ion channels in biological cell membranes and solid state nanopores.Comment: to appear in Nature Nanotechnolog
- …