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Comparing Outcomes Between the Over-the-Top and All-Epiphyseal Techniques for Physeal-Sparing ACL Reconstruction: A Narrative Review.
A variety of techniques are used for physeal-sparing anterior cruciate ligament (ACL) reconstruction; however, there is no clear consensus on the ideal surgical technique, the frequency of complications, and how to best avoid growth disturbance. The purpose of this study was to compare outcomes and complications between over-the-top and all-epiphyseal ACL reconstruction techniques. The hypothesis was that both physeal-sparing reconstruction techniques are efficacious, with similar risk of growth disturbance and complications. The Embase and PubMed databases were queried for studies on ACL ruptures in the skeletally immature population from 1985 to 2018. Full-text English studies were included (N = 160). Studies reporting rerupture and/or complications after physeal-sparing ACL reconstruction, specifically growth disturbance, were included (n = 10). Studies were separated into 2 groups: an all-epiphyseal group with femoral and tibial fixation points within the epiphysis and a group that had over-the-top femoral and tibial physeal-sparing reconstruction. Complications not specific to the pediatric population were excluded. Demographics, evaluation of skeletal maturity, surgical technique, growth disturbance, rerupture, and patient-reported outcome scores were collected. Data were analyzed in aggregate. The 10 studies included 482 knees. The mean age was 12.0 years; 81% of patients were male; and mean follow-up was 47.7 months. A total of 178 patients underwent all-epiphyseal reconstruction, and 298 had the femoral graft placed over the top. The rerupture rate was 9.0% (16 of 178) in the all-epiphyseal group and 7.2% (14 of 195) in the over-the-top group, of which 82% required revision reconstruction. Six patients had overgrowth in the all-epiphyseal group (mean, 1.8 cm) and 1 patient in the over-the-top group (1.5 cm). Three angular deformities occurred, all of which were in the over-the-top group. Both physeal-sparing ACL reconstruction techniques are successful. Overgrowth was more common in the all-epiphyseal group and angular deformity in the over-the-top group. Rerupture rates were similar between the groups. The authors recommend standardization of skeletal age assessment and baseline lower extremity alignment films
Temperature Variation of Debye-Waller Factor and Mean Square Displacement for some Transition Metals
Template Assisted Growth Of Zinc Oxide-Based Nanowires By Electrochemical Deposition
Ordered ZnO and Zn1 – xCdxO nanowire/nanorod arrays were fabricated by cathodic electrodeposition based on anodic alumina (AAO) membrane and polycarbonate membrane (PCM) from an aqueous solution containing zinc nitrate precursor at different bath temperatures. The electrodeposition process involves the electroreduction of nitrate ions to alter the local pH within the pores and precipitation of the metal oxide within the pores. X-Ray diffraction measurements showed that the nanowires/nanorods were of wurtzite crystallographic structures and the average length and diameter of nanorods were measured by SEM and TEM. HRTEM measurements confirm the crystallinity and elemental composition of grown nanowires on PCM/AAO templates.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/963
Accuracy, Scalability, and Efficiency of Mixed-Element USM3D for Benchmark Three-Dimensional Flows
The unstructured, mixed-element, cell-centered, finite-volume flow solver USM3D is enhanced with new capabilities including parallelization, line generation for general unstructured grids, improved discretization scheme, and optimized iterative solver. The paper reports on the new developments to the flow solver and assesses the accuracy, scalability, and efficiency. The USM3D assessments are conducted using a baseline method and the recent hierarchical adaptive nonlinear iteration method framework. Two benchmark turbulent flows, namely, a subsonic separated flow around a three-dimensional hemisphere-cylinder configuration and a transonic flow around the ONERA M6 wing are considered
Računanje vrpčaste strukture nelokalnim pseudopotencijalima
Energy bands of Rb and Cs have been calculated for the first time using average or effective pseudopotentials obtained from non-local ones. It is shown that the results so obtained compare well to those obtained with full non-local calculations.Načinili smo prve račune energijskih vrpci Rb i Cs primjenom prosječnog ili efektivnog pseudopotencijala koji smo izveli iz nelokalnih pseudopotencijala. Pokazuje se dobra suglasnost ishoda tih računa i računa primjenom potpunih nelokalnih pseudopotencijala
Računanje vrpčaste strukture nelokalnim pseudopotencijalima
Energy bands of Rb and Cs have been calculated for the first time using average or effective pseudopotentials obtained from non-local ones. It is shown that the results so obtained compare well to those obtained with full non-local calculations.Načinili smo prve račune energijskih vrpci Rb i Cs primjenom prosječnog ili efektivnog pseudopotencijala koji smo izveli iz nelokalnih pseudopotencijala. Pokazuje se dobra suglasnost ishoda tih računa i računa primjenom potpunih nelokalnih pseudopotencijala
Scaling of Circulation in Buoyancy Generated Vortices
The temporal evolution of the fluid circulation generated by a buoyancy force
when two-dimensional (2D) arrays of 2D thermals are released into a quiescent
incompressible fluid is studied through the results of numerous lattice
Boltzmann simulations. It is observed that the circulation magnitude grows to a
maximum value in a finite time. When both the maximum circulation and the time
at which it occurs are non-dimensionalised by appropriately defined
characteristic scales, it is shown that two simple Prandtl number (Pr)
dependent scaling relations can be devised that fit these data very well over
nine decades of Pr spanning the viscous and diffusive regimes and six decades
of Rayleigh number (Ra) in the low Ra regime. Also, obtained analytically is
the exact result that circulation magnitude continues to grow in time for a
single buoyant vortex ring in an infinite unbounded fluid.Comment: 4 pages, 3 figures, submitted to Physical Review Letter
Enhancement of USM3D Unstructured Flow Solver for High-Speed High-Temperature Shear Flows
Large temperature and pressure fluctuations have a profound effect on turbulence development in transonic and supersonic jets. For high-speed, high-temperature jet flows, standard turbulence models lack the ability to predict the observed mixing rate of a shear layer. Several proposals to address this deficiency have been advanced in the literature to modify the turbulence transport equations in a variety of ways. In the present study, some of the most proven and simple modifications to two-equation turbulence models have been selected and implemented in NASA's USM3D tetrahedral Navier-Stokes flow solver. The modifications include the addition of compressibility correction and pressure dilatation terms in the turbulence transport equations for high-speed flows, and the addition of a simple modification to the Boussinesq's closure model coefficient for high-temperature jets. The efficacy of the extended models is demonstrated by comparison with experimental data for two supersonic axisymmetric jet test cases at design pressure ratio
Measurements and ab initio Molecular Dynamics Simulations of the High Temperature Ferroelectric Transition in Hexagonal RMnO3
Measurements of the structure of hexagonal RMnO3 (R=rare earths (Ho) and Y)
for temperatures significantly above the ferroelectric transition temperature
(TFE) were conducted to determine the nature of the transition. The local and
long range structural measurements were complemented by ab initio molecular
dynamics simulations. With respect to the Mn sites in YMnO3 and HoMnO3, we find
no large atomic (bond distances or thermal factors), electronic structure
changes or rehybridization on crossing TFE from local structural methods. The
local symmetry about the Mn sites is preserved. With respect to the local
structure about the Ho sites, a reduction of the average Ho-O bond with
increased temperature is found. Ab initio molecular dynamics calculations on
HoMnO3 reveal the detailed motions of all ions. Above ~900 K there are large
displacements of the Ho, O3 and O4 ions along the z-axis which reduce the
buckling of the MnO3/O4 planes. The changes result in O3/O4 ions moving to
towards central points between pairs of Ho ions on the z-axis. These structural
changes make the coordination of Ho sites more symmetric thus extinguishing the
electric polarization. At significantly higher temperatures, rotation of the
MnO5 polyhedra occurs without a significant change in electric polarization.
The born effective charge tensor is found to be highly anisotropic at the O
sites but does not change appreciably at high temperatures
End wall flows in rotors and stators of a single stage compressor
A solution of the flow in the rotor end wall region, including the effects of tip clearance flow, is presented. A method for leakage flow measurement at the tip of a compressor rotor blade is discussed. Measurements are given for a rotor hub wall boundary layer
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