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In this study we quantified and characterised the return of functional mobility following open tibial fracture using the Hamlyn Mobility Score. A total of 20 patients who had undergone reconstruction following this fracture were reviewed at three-month intervals for one year. An ear-worn movement sensor was used to assess their mobility and gait. The Hamlyn Mobility Score and its constituent kinematic features were calculated longitudinally, allowing analysis of mobility during recovery and between patients with varying grades of fracture. The mean score improved throughout the study period. Patients with more severe fractures recovered at a slower rate; those with a grade I Gustilo-Anderson fracture completing most of their recovery within three months, those with a grade II fracture within six months and those with a grade III fracture within nine months. Analysis of gait showed that the quality of walking continued to improve up to 12 months post-operatively, whereas the capacity to walk, as measured by the six-minute walking test, plateaued after six months. Late complications occurred in two patients, in whom the trajectory of recovery deviated by > 0.5 standard deviations below that of the remaining patients. This is the first objective, longitudinal assessment of functional recovery in patients with an open tibial fracture, providing some clarification of the differences in prognosis and recovery associated with different grades of fracture.Cite this article: Bone Joint J2015; 97-B:1118–25. more...

As anode material used in power storage device, lithium ion battery (LIB) for example, ZnO has not been recognized as a promising candidate, although which shows advantages like environmental benign, low cost, and large reservation. Several problems, such as volume expansion, pulverization, and active substance detachment because of the particular lithiation kinetics, which result in very high irreversible capacity and following fading, can account for the present situation. Here in this work, we report the self-assembly of ZnxGe1–xO three-dimensional (3D) micronano structures and achieve enormous improvement on both recyclability and rate performance. After the 100th cycle, the capacity remains ∼690 mAh/g at the rate of 100 and ∼510 mA/g at the rate of 500 mAh/g. The capacity recovered rapidly even the rates alternating repeatedly between 50 mA/g and 3.5A/g. Ex situ observation reveals that substance detachment and nanoparticle agglomeration were avoided, benefiting from the firm 3D space configuration. As the Li+insertion, the 3D architectures fracture hierarchically with releasing the volume-expansion produced strain. Stable and smooth Li+/electrons path would form in these nanoparticles integrated microfragments, which act as the working unit free of further detachment. These facts demonstrate that ZnO based anode materials are anticipant to be good candidate in LIB device through rational design of advanced mirco-nano structures without introduction of carbon coating. more...

The increase in the use of robotic assisted surgery has provided benefits to both the patient and the surgeon. There are possibilities for training and surgical planning and guidance within this framework but work is needed for this to reach a patient-specific level. Medical images obtained prior to surgery are used clinically to plan operations and there has been much research in their use to build models, giving further knowledge of tissue and organ structures. The incorporation of this data into the surgical environment is a recent development, assisting the surgeon with orientation information, but motion due to respiration or changes to morphology due to intervention begets a need for the incorporation of real-time imaging into the modelling. The current work on pre-operative and intra-operative imaging and modelling methods for robotic assisted surgery has to be reviewed and then the Image Constrained Biomechanical Modelling has to be introduced, whereby patient-specific biomechanical modelling is based on the underlying medical images, reducing the computational complexity involved with traditional biomechani-cal modelling. This article concludes with a discussion of the possible and promising future directions of this work. more...

SiC nanowires have been fabricated by a simple catalyst-free method using detonation soot powders and silicon wafers. We characterize their microstructures by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The results show that the nanowires consist of single-crystalline β phase SiC cores with diameters of 30−100 nm and lengths of 0.5−1.5 μm wrapped with a very thin amorphous oxide layer. The axial growth direction of each nanowire is preferentially along the κ direction, while the low density of planar defects are detected. Unique optical properties are found in the Raman spectroscopy that has a blue shift of about 8 cm−1compared to the bulk β-SiC crystal. Furthermore, field-emission measurements show a relativly low threshold field of 6.2 Vμm−1, suggesting that it is a promising material for applications in flat panel display. Finally, a possible growth model based on a VS mechanism was proposed to explain the growth of the SiC nanowires. more...

Posture analysis is an active research area in computer vision for applications such as home care and security monitoring. This paper describes the design of a system for posture analysis with hardware acceleration, addressing the following four aspects: (a) a design workflow for posture analysis based on radial shape and projection histogram representations; (b) the implementation of different architectures based on a high-level hardware design approach with support for automating transformations to improve parallelism and resource optimisation; (c) accuracy evaluation of the proposed posture analysis system, and (d) performance evaluation for the derived designs. One of the designs, which targets a Xilinx XC2V6000 FPGA at 90.2 MHz, is able to perform posture analysis at a rate of 1,164 frames per second with a frame size of 320 by 240 pixels. It represents 3.5 times speedup over optimised software running on a 2.4 GHz AMD Athlon 64 3700+ computer. The frame rate is well above that of real-time video, which enables the sharing of the FPGA among multiple video sources. more...

A Ag:Y Ba2Cu3O7??/SrNb0.01Ti0.99O3bilayer structure was fabricated by pulsed-laser deposition. Current-voltage (I-V) dependence measurements of the bilayer were carried out in the temperature range 5-250 K with variation of magnetic field from 0 to 50 kOe. Schottky junction behaviour was observed at temperatures higher than the critical temperature of superconductivity (Tc) due to the n-type semiconductor SrNb0.01Ti0.99O3and the metallic conductivity of Y Ba2Cu3O7??. At temperatures lower than Tc, the bilayer becomes a degenerate heterostructure p-n junction. The I-Vcharacteristic shows a sequence of current steps at forward voltage and an oscillation character at backward voltage. Energy diagrams of the Ag:Y Ba2Cu3O7??/SrNb0.01Ti0.99O3bilayer structure have been proposed to explain the peculiar I-Vcharacteristics. more...

A Ag:Y Ba₂Cu₃O_7−δ/SrNb_0.01Ti_0.99O₃ bilayer structure was fabricated by pulsed-laser deposition. Current–voltage (I–V) dependence measurements of the bilayer were carried out in the temperature range 5–250 K with variation of magnetic field from 0 to 50 kOe. Schottky junction behaviour was observed at temperatures higher than the critical temperature of superconductivity (T_c) due to the n-type semiconductor SrNb_0.01Ti_0.99O₃ and the metallic conductivity of Y Ba₂Cu₃O_7−δ. At temperatures lower than T_c, the bilayer becomes a degenerate heterostructure p–n junction. The I–V characteristic shows a sequence of current steps at forward voltage and an oscillation character at backward voltage. Energy diagrams of the Ag:Y Ba₂Cu₃O_7−δ/SrNb_0.01Ti_0.99O₃ bilayer structure have been proposed to explain the peculiar I–V characteristics. more...

Thin films of La0.7Sr0.3MnO3 with thickness of 300 nm have been grown by computer-controlled laser molecular beam epitaxy on SrTiO3 (001) substrate and were characterized by transmission electron microscopy. It is seen that the films are epitaxially grown on SrTiO3 substrate. Microstructures in the films are clarified by oriented domains of the rhombohedral variant derived from the perovskite structure. Relationships between each domain and the SrTiO3 substrate are discussed. more...

This paper presents an automatic method of correcting non-uniform RF coil response for the classification of body composition using MR imaging. By linear mosaic modelling, the smoothly but non-linearly varying bias field, which modulates tissue intensities within the image, was corrected. The overlapping between adjacent mosaics ensured consistent segmentation of body fat content and the effectiveness of the technique was validated by both phantom and in vivo experiments. Ten whole body composition data sets, each with 39 trans-axial slices, were acquired. Automatic segmentation results using the proposed technique were compared with those from manual delineations. The automatic segmentation method was found to be highly accurate and the mean percentage error between the two methods was less than 1.5%. more...

A series of BaTiO 3 p-n junctions have been successfully fabricated including BaTi 1 m x Nb x O 3 /BaTi 1 m x In x O 3 BaTi 1 m x In x O 3 /SrTi 1 m x Nb x O 3 by Laser molecular beam epitaxy. Better I-V curves of p-n junctions have been obtained. more...

Abstract:: We study the nonclassical properties and algebraic characteristics of the negative binomial states introduced by Barnett recently. The ladder operator formalism and displacement operator formalism of the negative binomial states are found and the algebra involved turns out to be the SU(1,1) Lie algebra via the generalized Holstein-Primarkoff realization. These states are essentially Perelomov's SU(1,1) coherent states. We reveal their connection with the geometric states and find that they are excited geometric states. As intermediate states, they interpolate between the number states and geometric states. We also point out that they can be recognized as the nonlinear coherent states. Their nonclassical properties, such as sub-Poissonian distribution and squeezing effect are discussed. The quasiprobability distributions in phase space, namely the Q and Wigner functions, are studied in detail. We also propose two methods of generation of the negative binomial states. d 32.80.Pj Optical cooling of atoms; trapping more...

Abstract:: The scanning electrostatic force microscopy (SEFM) can acquire information of surface structures in a non-contact way. We calculate the electrostatic force between the charged tip and polarized surface structure in SEFM in the framework of self-consistent integral equation formalism (SCIEF), incorporating the image method to treat the electrostatic coupling of substrate and tip. We consider two kinds of surface structures, one is the topographic structure on the surface, the other is the dielectric structure embedded in the substrate. The force pattern of the topographic structure shows a protrusion around the surface structure. However, the force pattern displays a hollow around an embedded structure with a dielectric constant less than that of substrate medium. For an embedded structure with a larger dielectric constant, the force pattern exhibits a protrusion, and the force signal is much weaker than that of the topographic structure. Therefore, it is expected that one may identify these surface structures from the pure electrostatic force information in SEFM. The force signal of the densely arranged dielectric pads is simply the superposition of force signal of each pad individually, the interference effect of electric field is not remarkable. more...

High quality BaTiO3 thin films have been epitaxially grown on SrTiO3 (100) substrates by pulsed laser deposition (PLD) using a single crystal target. The BaTiO3/YBa2Cu3O7 bilayer staictures have also been grown on LaAlO3(100) substrate by PLD for ferroelectric thin film devices. All the two kinds of thin films were analysed by x-ray diffraction, high resolution transmission electron microscopy and scanning electron microscopy. more...

Abstract:: In this paper we study the influence of the magneto-coupling effect between the longitudinal motion component and the transverse Landau orbits of an electron on transmission features in single barrier structures. Within the parabolic conduction-band approach, a modified one-dimensional effective-mass Schrödinger equation, including the magneto-coupling effect generated from the position-dependent effective mass of the electron, is strictly derived. Numerical calculations for single barrier structures show that the magneto-coupling effect brings about a series of the important changes for the transmission probability, the above-barrier quasi-bound states, and the tunneling time. Through examining the variation of the above-barrier resonant-transmission spectrum with the barrier width and observing the well-defined Lorentzian line-shape of the above-barrier resonant peaks, we convincingly show that the above-barrier resonant transmission in single barrier structures is delivered by the above-barrier quasibound states in the barrier region, just as the below-barrier resonant tunneling in double barrier structures is mediated by the below-barrier quasi-bound states in the well. Furthermore, we come to the conclusion that the magneto-coupling effect brings about not only the splitting of the above-barrier quasi-bound levels but also the striking reduction of the level-width of the quasi-bound states, correspondingly, the substantial increase of the density of the quasi-bound states. We suggest that magneto-coupling effects may be observed by the measurements of the optical absorption spectrum associated with the above-barrier quasi-bound states in the single barrier structures. more...

Several pulmonary conditions are characterized by the finding of areas of decreased attenuation relative to adjacent normal lung parenchyma on computed tomography. In particular, the identification of areas of the lung affected by small airways disease is difficult as the reduction in lung density is subtle and the regions are poorly marginated. This paper presents a novel wavelet analysis technique which increases the conspicuity of differences between normal and abnormal lung parenchyma. more...

The effect of the structure YBa2Cu3O7-x superconducting thin films on microwave surface resistance was investigated. The electon channeling patterns (ECPs) and X-ray experimental results showed that the microwave surface resistanceRs is strongly correlated with the perfection of the thin films. The films were deposited on LaAlO3(100) and YSZ(100) substrates. For thin film withRs of 280µO, the crystallinity of the thin film shown byw-scanning andf-scanning was excellent and the ECPs were very sharp. For thin film with highRs of 98 mO, only bands from the major zone were visible in the ECPs, which suggested poor crystallinity of the film. From this investigation it was shown that the more perfect the thin films, the lower theRs. more...

The surface morphology and growth mechanism ofc-oriented YBa2Cu3O7 thin films deposited on Y-stabilized zirconia substrate by laser deposition has been investigated with scanning tunneling microscopy. Both screw dislocation and layered island growth processes took place. Surface features such as screw dislocation, steps, subgrain boundaries, holes, and troughs were present, suggesting that they may act as pinning sites for flux lines. A thin layer of nonsuperconducting material with a thickness of a few angstroms is seen on the surface of the film. more...

We have investigated the superconducting behavior of high-Tc YBa2Cu3O7 (YBCO) thin films containing BaO impure phase produced by pulsed laser deposition. The thin films were characterized by the standard four-probe method, X-ray diffraction (XRD), and scanning electron microscopy (SEM). XRD showed that all these thin films contained BaO impurity, with thec-axis normal to the surface of the substrates. The presence of impurity existed from substrate temperatureTs of 727 to 796°C. When these thin films with BaO impurity were measured under the magnetic fields, it was found that the critical current densityJc increased slightly with increase in magnetic fieldB within the range ofB=500 G, in the case ofB perpendicular to thec-axis of the film. more...

YBa2Cu3O7 superconducting thin films were deposited onR-plane sapphire substrates with Yttria-stabilized zirconia buffer layer by laser ablation. The structure of the films was characterized by X-ray diffraction. Superconducting transitional temperatures as high as =90 K and critical current densities up to 2.2×106 A/cm2 (77 K) were achieved. The results of Auger depth profile showed that no obvious diffusion occurred between the substrate and the YBa2Cu3O7 thin film. more...

Conclusions Functional evaluation of the cardiovascular system using rapid imaging (spiral echo planar), chemical shift, and velocity mapping is capable of making the diagnosis in congenital and acquired cardiovascular disease which, between them, cause the largest number of deaths of any disease in the western world and massive morbidity and suffering. Furthermore, for the first time in the history of medicine, there is the opportunity to apply preventive measures to eardicate the epidemic of preventable arterial disease. There needs to be a change of emphasis and a switching of resources to apply to the most common diseases rather than to those which are most easily studied. There also needs to be proper training in cardiovascular MR, not so much for imagers as for cardiologists and experts in vascular disease. more...

We used magnetic resonance imaging with cine velocity vector mapping to study blood flow patterns in the thoracic aorta of patients with aortic aneurysms. Spin-echo images of the thoracic aorta were acquired in orthogonal and oblique planes. Cine phase-shift velocity maps were then acquired in selected aortic planes, with velocity encoded in two orthogonal directions. The two-directional velocity data were processed to generate flow vector maps depicting flow distribution in the chosen plane. Diameter ratios between the aortic valves and aneurysmal ascending aortas were reduced, causing blood to enter as a relatively narrow stream with lateral vortical, recirculating flow. In atherosclerotic aneurysms, there was abnormal angulation between the left ventricular outflow tract and ascending aorta, causing the stream to attach to the anterior aortic wall, with recirculating flow posteriorly. In Marfan patients, the primary stream was central with vortices on either side. In patients with coarctation, the main stream attached to the posterior wall of the descending aorta, with recirculation anteriorly. Magnetic resonance imaging with cine velocity mapping allows comprehensive assessment of aortic anatomy and blood flow patterns. Sequential studies at early stages may provide new information about the natural history of aortic aneurysms. more...

High-sensitivity and visible-blind ultraviolet (UV) photoconductive detectors based on SrTiO_3 single crystal with interdigitated electrodes are reported. The responsivities of photovoltage and photocurrent can reach 2.13×10^5 V/W and 213 mA/W, respectively, at 330 nm at ambient temperature, and the corresponding quantum efficiency η reaches 80.2%. The dark current is lower than 50 pA at 10 V bias, and the UV/visible contrast ratio is about four orders of magnitude with a sharp cutoff at 390 nm. The experimental results demonstrate that SrTiO_3 single crystal has potentially wide applications in UV detection. more...

Superconducting MgB₂ thin films were fabricated on Al₂O₃(0001) and MgO(100) substrates by a two-step method. Boron thin films were deposited by pulsed laser deposition followed by an ex-situ annealing process. Resistance measurements of the deposited MgB₂ films show a T_c of 38.6 K for MgB₂/Al₂O₃ and 38.1 K for MgB₂/MgO. Atomic force microscopy, scanning electron microscopy and x-ray diffraction were used to study the properties of the films. The results indicate that the MgB₂/Al₂O₃ films consist of well-crystallized grains with a highly c-axis-oriented structure while the MgB₂/MgO films have a dense uniform appearance with an unfixed orientation. more...