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Stiff knee gait is a troublesome gait disturbance related to spastic paresis, frequently associated with overactivity of the rectus femoris muscle in the swing phase of gait.The aim of this study was to assess the short-term effects of rectus femoris neurotomy for the treatment of spastic stiff-knee gait in patients with hemiparesis.An Intervention study (before-after trial) with an observational design was carried out in a university hospital. Seven ambulatory patients with hemiparesis of spinal or cerebral origin and spastic stiff-knee gait, which had previously been improved by botulinum toxin injections, were proposed a selective neurotomy of the rectus femoris muscle. A functional evaluation (Functional Ambulation Classification and maximal walking distance), clinical evaluation (spasticity - Ashworth scale and Duncan-Ely test, muscle strength - Medical Research Council scale), and quantitative gait analysis (spatiotemporal parameters, stiff knee gait-related kinematic and kinetic parameters, and dynamic electromyography of rectus femoris) were performed as outcome measures, before and 3 months after rectus femoris neurotomy.Compared with preoperative values, there was a significant increase in maximal walking distance, gait speed, and stride length at 3 months. All kinematic parameters improved, and the average early swing phase knee extension moment decreased. The duration of the rectus femoris burst decreased post-op.This study is the first to show that rectus femoris neurotomy helps to normalise muscle activity during gait, and results in improvements in kinetic, kinematic, and functional parameters in patients with spastic stiff knee gait.

The blade row interaction can alter the time-mean flow and therefore be of interest for aerodynamic design analysis. Whereas results within low subsonic turbomachines are quite numerous in the literature, there have been far fewer works which give results of blade row interaction within high speed cases. Two cases are related in this paper. First, the effects of an incoming wake on the rotor flow field of a transonic compressor are analyzed. The blade row interaction proved to be positive regarding the total pressure ratio, but negative regarding the losses. The second case concerns a transonic turbine. Particular emphasis is placed on the assessment of the deterministic correlations included in the Averaged Passage Equation System.

In this first of two articles, we discuss some issues surrounding the dissolution rate enhancement of poorly-soluble active ingredients micronized into nano-particles using several supercritical fluid particle design processes including rapid expansion of supercritical solutions (RESS), supercritical anti-solvent (SAS) and particles from gas-saturated solutions/suspensions (PGSS). Experimental results confirm that dissolution rates do not only depend on the surface area and particle size of the processed powder, but are greatly affected by other physico-chemical characteristics such as crystal morphology and wettability that may reduce the benefit of micronization.

In this second of two articles, we show that several supercritical processes have been developed to prepare composite particles of poorly soluble active ingredients. Microencapsulation, cyclodextrin inclusion and impregnation allow to incorporate poorly soluble materials in fast-dissolving hydrophilic excipients, leading to promising results in terms of dissolution rate enhancement.

Infection with Trichomonas vaginalis during pregnancy has been associated with preterm delivery. It is uncertain whether treatment of asymptomatic trichomoniasis in pregnant women reduces the occurrence of preterm delivery.We screened pregnant women for trichomoniasis by culture of vaginal secretions. We randomly assigned 617 women with asymptomatic trichomoniasis who were 16 to 23 weeks pregnant to receive two 2-g doses of metronidazole (320 women) or placebo (297 women) 48 hours apart. We treated women again with the same two-dose regimen at 24 to 29 weeks of gestation. The primary outcome was delivery before 37 weeks of gestation.Between randomization and follow-up, trichomoniasis resolved in 249 of 269 women for whom follow-up cultures were available in the metronidazole group (92.6 percent) and 92 of 260 women with follow-up cultures in the placebo group (35.4 percent). Data on the time and characteristics of delivery were available for 315 women in the metronidazole group and 289 women in the placebo group. Delivery occurred before 37 weeks of gestation in 60 women in the metronidazole group (19.0 percent) and 31 women in the placebo group (10.7 percent) (relative risk, 1.8; 95 percent confidence interval, 1.2 to 2.7; P=0.004). The difference was attributable primarily to an increase in preterm delivery resulting from spontaneous preterm labor (10.2 percent vs. 3.5 percent; relative risk, 3.0; 95 percent confidence interval, 1.5 to 5.9).Treatment of pregnant women with asymptomatic trichomoniasis does not prevent preterm delivery. Routine screening and treatment of asymptomatic pregnant women for this condition cannot be recommended.

A time-dependent numerical simulation of a single-stage transonic turbine is used as a direct simulation of stator-rotor interactions. The different parts of the deterministic correlations are computed and compared. The present work aims to provide insight into the influence of these correlations on the steady flow field of the average-passage equation system. This is related to the deterministic models of the literature. Several steady computations are performed with the various correlations. These results are compared with the time-averaged flow field. The impact of boundary conditions is also studied to highlight the importance of the non-uniform circumferential distribution at the so-called ‘mixing plane’. This work establishes that a non-uniform circumferential distribution is a key to ensure the success of steady computation. Furthermore, it demonstrates that full deterministic correlations are necessary to reproduce the time-averaged flow field. Spatial correlations are thus insufficient to model the stator wakes that interact with the rotor. Steady computations using only spatial correlations give less accurate results than those obtained without any correlation. This is a serious flaw of most of the literature's models.

This study deals with a new calculation method which consists in coupling a throughflow calculation with a 3D code. The aim of this development is to simulate flows in multistaged turbomachines with variable rotating speed. To calculate the steady 3D relative flow of each isolated row embedded in a multistaged configuration, accurate boundary conditions, function of the influence of the other rows, are needed upstream and downstream. In our method, those conditions are imposed in a coupling process, as results of a throughflow calculation. This code solves the circumferentially averaged Euler equations on a multistaged domain. Because the averaging process generates source terms usually known as blades forces and deterministic stresses function of 3D variables fields, the throughflow calculation and the 3D calculations, one per row, are realised in the same process. Periodically during the time-marching evolution of the throughflow calculation, 3D calculations are done using boundary conditions from it. When they are finished, throughflow calculation source terms are restored. The coupling process continues, until the throughflow calculation convergence is obtained. The 3D code used is CALECHE, which solves the 3D incompressible Euler equations written with the Clebsch variables. The method has been successfully validated on an axial compressor stage, and preleminary results are presented on isolated row with fast start of rotating speed.

Compact multi-wavelength light sources have been developed to provide flexibility in pulse oximeter device design. Advantages of these light sources include emitting light of multiple wavelengths with a constant ratio of intensity, and a co-linear light propagation path through tissue. These devices can function as normal pulse oximeter to determine oxygen saturation and pulse rate, but this approach potentially reduces circuit complexity, reduces motion artifacts and enables multi-wavelength sensing of different forms of hemoglobin or other blood products.

A direct numerical simulation (DNS) of three-dimensional turbulent reacting channel flows taking into account the buoyancy effect was carried out using a spectral method. The statistical results from the DNS database are used to validate an algebraic sub-grid scale combustion model (ASSCM), which was studied in gas combustion previously. Comparison between the exact solution and the results of the correlations in the ASSCM model show good agreement in some cases while the results were acceptable other cases. A methane-air gas flame and a methanol-air two-phase spray flame were also simulated using the ASSCM model. The LES predicted temperature profile in both flames were close to the experimental data demonstrating the accuracy of the model.

We report on the metalorganic chemical vapor deposition of the quaternary alloy AlInGaN. We found it desirable to grow quaternary films at temperatures greater than 855 °C in order to suppress deep level emissions in the room-temperature photoluminescence. Details of the conditions necessary to grow In0.1Ga0.9N at 875 °C are presented. Strained and relaxed AlInGaN films were grown with good optical and structural properties for AlN compositions up to 26% and InN content up to 11%. The effects of strain were observed by a difference in the band gap between thin and thick films with the same compositions. The potential impact of the use of quaternary films is discussed regarding strain engineering for the improvement of present device designs.

Main topics: Technical developments in movement science, Experimental studies in human movement science Introduction and aim: Quality of the popular Plug-in Gait (PiG) model [1] outputs depends primarily on marker positioning. Among them, thewandmarkersplacedon the thighsandshanksare especially difficult to position because they involve non-palpable anatomical points: the hip and the knee joint centers, respectively. This communication presents an optimal method for positioningwandmarkers using a real-time process.We examine the effect of thismethod on two operators (expert and non-expert). This process is expected to reduce the inter-session variability [2] and the maximum of the varus-valgus knee angle during swing phase. Patients/materials and methods: Gait data were collected on ten healthy subjects (62±10kg, 1.69±0.09m) with an optoelectronic motion capture system (Vicon, Oxford Metrics). Except the wand markers, all the PiG markers, plus medial markers were placed by an expert operator (5-year experience in gait analysis). A custom program using the Vicon RealTime SDK was implemented in Matlab. It indicated when the thigh wand marker, for example, belonged to the plan formed by the hip joint center, the lateral and medial condyles, with a tolerance of ±1mm. Firstly, each subject participated in four gait sessions, two with and twowithout real-time positioning by the expert. Between each session, the wand markers were fully removed. Four other gait sessionswere then carried outwith non-experts as operator (physiotherapist students without experience in gait laboratory). Kinematics PiG data were calculated by the use of the Biomechanical toolkit [3]. A two-way mixed-anova examined the effect of the realtime process and operators. Results: Real-time positioning significantly reduced the intersession variability of knee angles for the non-expert (Fig. 1). For the expert, only the flexion-extension was different. Similarly, a significant difference of 6 degrees (Table 1) was observed for the maximal knee var/valgus angle provided from the non-expert positioning. Thanks to the real-time process, themaximal var/valgus of the non-expert did not differ from the expert one.

The time resolved and DC photoconduction characteristics of Si nanowire devices are described. Si nanowires with diameters ranging from 20-100 nm were grown using the vapor-liquid-solid (VLS) growth mechanism under standard conditions and devices were fabricated in a back-gate field effect transistor (FET) configuration using simple photolithography. It is shown that under certain biasing conditions, illumination with light from light emitting diodes with wavelengths ranging from 480 nm to 625 nm causes changes in current as high as 4%. On the other hand, illumination by a broadband incandescent source causes a ∼4.1% percent change in current. Photoconductive decay curves show bi- and tri-exponential behavior, indicative of multiple potential recombination mechanisms occurring within the Si nanowire devices. p-n doped Si nanowires show similar behavior. Studies under various drain and gate voltages provides insight into the proposed mechanism. It is argued that the Shottky barrier plays a strong role in the observed photoconduction process in these wires, as do transitions involving surface and deep level trap states.

Blue and near-ultraviolet (UV) InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) were grown on GaN and sapphire substrates using metalorganic chemical vapor deposition. The homoepitaxial LEDs exhibited greatly improved microstructural and electrical properties compared to the devices grown on sapphire. As a result of defect reduction, the reverse-bias leakage current was reduced by more than six orders of magnitude. At forward bias, thermally activated current rather than carrier tunneling was dominant in the LEDs on GaN. The improvement of optical characteristics was found to be a strong function of In content in the active region. At low and intermediate injection levels, the internal quantum efficiency of the UV LED on GaN was much higher compared to that on sapphire, whereas the performance of the blue LEDs was found to be comparable. At high injection currents, both the blue and UV LEDs on GaN greatly outperformed their counterparts on sapphire. The homoepitaxial LEDs with a vertical geometry had a much smaller series resistance and were capable of operating at 600 A/cm 2 in cw mode due to uniform current spreading and efficient heat dissipation.

In this first of two articles, we discuss some issues surrounding the dissolution rate enhancement of poorly-soluble active ingredients micronized into nano-particles using several supercritical fluid particle design processes including rapid expansion of supercritical solutions (RESS), supercritical anti-solvent (SAS) and particles from gas-saturated solutions/suspensions (PGSS). Experimental results confirm that dissolution rates do not only depend on the surface area and particle size of the processed powder, but are greatly affected by other physico-chemical characteristics such as crystal morphology and wettability that may reduce the benefit of micronization.

In this second of two articles, we show that several supercritical processes have been developed to prepare composite particles of poorly soluble active ingredients. Microencapsulation, cyclodextrin inclusion and impregnation allow to incorporate poorly soluble materials in fast-dissolving hydrophilic excipients, leading to promising results in terms of dissolution rate enhancement.

In this paper we present the electro-optical model, using Aimspice in conjunction with a resistor network, for evaluating the LED designs for optimum uniform current spreading and efficient light extraction. Since high brightness is a critical factor for solid-state lighting, the ability for LED designs to be scalable is important, and we use the pinwheel design, which is aimed at increasing the p-contact area to aid in uniform current spreading, to demonstrate our model. The pinwheel LED design does not scale up because the percentage current uniformity decreases with device size and bias current. To validate the model the current voltage characteristics curves for the two LED sizes (X and 3X) are matched and the recombination saturation current densities values extracted as 7.8 x 10 -8 A/cm 2 and 8.6 x 10 -9 A/cm 2 , respectively. The tunneling saturation current densities for smallest LED, X, is two orders of magnitude lower than the larger device (3X). Although the larger the LED the higher the photon generation, only a small fraction of these photons can escape the device. The largest photon density is generated under the p-metal contact, with decreasing generation towards the edge of the mesa. Since the metal is opaque to the photons, there is that tendency for most of the photons in this region to bounce back and forth in the device and finally get absorbed. For the 3X pinwheel LED at 20 mA forward current, the complimentary experimental and calculated results show that only 2.2% of the generated photons can escape the active region and make it to the outside world.

This paper deals with the development of a multidomain/multiresolution method with application to RANS-LES coupling. In order to lower the computational cost, it is proposed to use LES in small subdomains embedded in larger RANS subdomains. This coupled approach results in the definition of a general multidomain problem. The main feature of the method is the interface condition between RANS and LES solutions. An original algorithm is proposed and assessed for the plane channel configuration.

The start-up of a turbomachine or, more generally, the large and quick variation of its rotational speed is rarely studied. Knapp1 has shown that in the case of a slow variation, the behavior of a turbomachine is quasi-steady. If the variation is quick, this is not true. This fact was confirmed by authors who have studied experimentally quick start-up of centrifugal hydraulic pumps. Tsukamoto and Ohashi2 have explained the basic mechanism of deviation from quasi-steadiness as a consequence of impulsive pressure and lag in formation of circulation around the blades. They have proposed a non-dimensional parameter of quasi-steadiness. Barrand and al3 have studied in depth the complex interaction between the pump and the components (ie pipelines, tank, valves.,) of the hydraulic circuit. They have also shown the effects of unsteady cavitation. Nguyen and al4 have analysed the behaviour of liquid hydrogen pumps during the start-up of space-rocket engines: they have concluded that the quasi-steady assumption is valid for these machines, a coherent result regarding the Tsukamoto-Ohashi parameter.

The aim of this work is to numerically investigate the different vortical structures present in the flow generated by a jet in crossflow. The test case which is relevant to an hydraulic experiment consists of a single jet ejecting normally into a laminar main stream. The computation is performed using a stationary three-dimensional Navier-Stokes code. A multi-block technique is used to compute the flow in the injection pipe. In addition high resolution is achieved in the region of jet-mainstream interaction. The flow analysis relies on the visualization of particle trajectories. These particles are introduced into vortex cores that are located by the secondary velocity field they induce. The three-dimensional behavior of these structures is enlightened. This provides us with the origin of the fluid of which they are comprised. The mixing between the jet and the incoming viscous layer appears to begin on the windward side of the jet boundary. Up to five types of vortices are identified including the well known counter rotating vortices that dominate the downstream flow. They clearly result from the stretching and warping of the annular vorticity rings issuing from the pipe. At the jet exit, they each split into two sub-structures with different growth and downstream development. Less prominent structures are also seen. The “horse shoe” vortex has been captured which is typical of the near wall effects due to blockage induced by the jet in the main stream. Its downstream legs are sucked through the jet boundary. Another weak structure located on the upstream jet boundary is the “lip” vortex which results from the upstream part of the flow specific topology. It is shown that viscous effects play an important role in both the generation and interaction between vortical structures.

When averaging the Navier-Stokes or Euler equations in the circumferential direction of a turbomachine, some so-called “spatial fluctuation terms” appear in the averaged conservation equations. We give the transport equations for these kinematic spatial fluctuation correlations. We evaluate the various terms in these equations, using the results of a three-dimensional Navier-Stokes computation. The test case is a highly loaded subsonic turbine stator. We discuss the magnitudes of the various terms. It is shown that blade force terms and diffusion terms have dominant effects, as respect to the production by the averaged field and the shear stress terms. The dissipation of the fluctuation kinetic energy occurs mainly in the passage vortex area, and in the blade wake.

The results of a computation, performed with a three-dimensional Navier-Stokes computation at ONERA, have been averaged in the blade-to-blade direction; the spatial fluctuations around the averaged flow variables have also been determined. It has then been possible to estimate all terms in the average components of the momentum equations. The comparison of the two-dimensional balances of these three equations shows that the shear stress play a minor role in the momentum balance, except on the dissipation of the passage vortex kinetic energy downstream of the blade trailing edges. The kinetic energy of the spanwise component of the velocity spatial fluctuations has a very strong influence on the radial pressure gradient; it introduces a convection effect. This is a key effect for all these balances.Copyright © 1993 by ASME

A three-dimensional computation has been performed for a supersonic axial flow compressor rotor by solving the NavierStokes equations. The results of the computation are used to analyse the tip leakage flow in more detail. As well as the global behaviour of the tip leakage vortex, the analysis focuses on the origins of this vortex. It is shown that the main source of its vorticity is the shear layer at the tip of the blade associated with the shedding of the blade loading. A separation occurs, with respect to the axial velocity component, as the jet leakage flow, crossing the clearance gap, encounters the upstream incoming flow. Although the entropy increase of this separation is low, it has a strong effect on the mixing around the leakage vortex. Overall, for this compressor and the choosen operating point, the tip leakage effects are localised near the tip wall and suction side of the blade. p � density a � stress tensor (.1) � rotation of the machine vorticity based on W

Pulsed infrared photocurrent spectroscopy is used to investigate deep levels in highly resistive metal organic chemical vapor deposition-grown, magnesium-doped aluminum gallium nitride metal-semiconductor-metal test structures in the range of aluminum fraction from x=0.0 to x=0.52. Some background level of photocurrent is observed at all infrared pump wavelengths between 1.35 and 4.0 μm. The photocurrent decay time is a decreasing function of aluminum fraction. A peak photocurrent energy is observed for each aluminum fraction. With increasing aluminum fraction, the peak blueshifts and narrows.

e16537 Background: Epithelial ovarian cancer (EOC) has a poor prognosis, and novel therapies are urgently needed. One-third of patients with EOC will develop clinical ascites, an adverse prognostic factor. The ascitic fluid is rich in tumor cells which can be purified and used as a valuable source of patient material for in vitro analysis. In this study, we describe a method to evaluate the efficacy of ascitic tumor cell killing by the oncolytic virus, JX-963 (vaccinia strain) currently approved for use in a NCIC-CTG phase I trial. Methods: Research ethics approval and patient consent was obtained for this study. 15 samples were collected prospectively with relevant clinicopathologic information. Infection with JX-963 was performed using viral doses ranging from a multiplicity of infection (MOI) of 0.5 to 8. Following a seven-day infection period, viability was assessed using the Alamar Blue metabolic assay and tracked by virally encoded green fluorescent protein (eGFP) expression, immunohistochemistry (IHC) and flow cytometry. Results: A standardized protocol was developed for the collection and purification of EOC cells from patient ascites for subsequent infection and quantification of viral killing. Qualitative analysis using phase contrast imaging of the total cell content showed greater opaque dead cell aggregates with increasing MOI over time. Although variable between individual samples, there was a strong correlation between escalating MOI and enhanced cell death in all patient ascites samples, when quantified by Alamar Blue assay and confirmed by flow cytometry and IHC. Similar cell killing profiles by JX-963 were observed for ascites tumor cells derived from both chemotherapy-naïve patients and chemotherapy-exposed (>1 prior line of chemotherapy) patients. Conclusions: EOC cells from patient ascites show effective but differential susceptibility to viral oncolysis by the JX-963 virus that appears to be independent of prior exposure to chemotherapy. The relevance of this work is that in an individual patient, this assay will allow the testing of panels of oncolytic viruses to identify candidate viral therapeutics which may predict response to treatment. No significant financial relationships to disclose.

The high temperature level reached at the exit of combustion chambers of modern aircraft engines and the practical limitations of advanced materials, demand efficient cooling of turbine blades. Optimization of the cooling requires an accurate prediction of aerodynamic losses and heat transfer on turbine blades. A new two-dimensional compressible, aerothermal boundary layer code has been developed. The formulation includes strong viscous-inviscid interaction, which enhances the stability properties of the code. The boundary layer equations associated with the energy equation are solved with an implicit Keller-box scheme. Viscous-inviscid flow coupling is performed by adding an interaction equation which has an elliptic character. The complete system of equations is solved by a multi-pass procedure. This technique contributes to the stabilization of the method and allows the computation of regions with strong adverse pressure gradients, separation bubbles and injections in case of film cooling. Comparisons between experimental and theoretical results are provided. Flow characteristics including heat transfer were computed for several cases such as flat plates with strong pressure gradients, and turbine blade boundary layers. Good agreement between computation and experiment is observed, demonstrating the high accuracy and robustness of the code.

The broadband optical absorption properties of silicon nanowire (SiNW) films fabricated on glass substrates by wet etching and chemical vapor deposition (CVD) have been measured and found to be higher than solid thin films of equivalent thickness. The observed behavior is adequately explained by light scattering and light trapping though some of the observed absorption is due to a high density of surface states in the nanowires films, as evidenced by the partial reduction in high residual sub-bandgap absorption after hydrogen passivation. Finite difference time domain simulations show strong resonance within and between the nanowires in a vertically oriented array and describe the experimental absorption data well. These structures may be of interest in optical films and optoelectronic device applications.

Various heterocumulenes RNCX (X = O, S, NR) insert readily into the MH bound of d 2 complexes [Cp 2 M(L)H](M = Nb, Ta and L = CO, PMe 2 Ph) to give the O -, S - or N -metallated derivatives [Cp 2 M(L)(η 1 -XCHNR)]. These products are photosensitive and by irradiation give quantitatively the heterometallacyclic compounds Cp 2 M(η 3 -XCHNR) by internal substitution of the L ligand.

Preparation de (η 5 -C 5 H 4 R) 2 Ta(CO)H 2 ) + PF 6 − qui reagit avec les derives carbonyle en donnant (η 5 -C 5 H 5 ) 2 Ta(CO) HOCHRR') + PF 6 − . En milieu basique, ces sels sont deprotones en (η 5 -C 5 H 5 ) 2 Ta(CO)(OCHRR')

Experiments have been performed with two cascades of turbomachines. The first cascade is composed of highly loaded turbine blades, and has been used in the low subsonic Mach number range. The second cascade consists of highly loaded compressor blades, of the DCA type. The Mach number was then in the high subsonic range. The experimental results are presented in the form of mean values in the pitch direction. Detailed local values are also described. The growth of a passage vortex and a corner effect are presented in the compressor case. Their interactions with the whole flow are analyzed. In the turbine case, the passage vortex is found to be a dominant effect. Results obtained with a theoretical method of calculation of the flow in the blade passage are used to complete the analysis.

The trihydrides Cp 2 MH 3 (M = Nb, Ta) react with diphenyl diazomethane giving Cp 2 M(diazo)H complexes in which the diazo molecule is η 2 - N,N -bonded to the metal. When Cp 2 TaH 3 is treated with the isonitrile CNCMe 2 CH 2 C(Me) 3 , the complex Cp 2 Ta[CH(CN)NR]H (R = CMe 2 CH 2 CMe 3 ) is obtained which contains an η 2 -coordinated CN bond.

Preparation de (η 5 -C 5 H 4 R) 2 Ta(CO)H 2 ) + PF 6 − qui reagit avec les derives carbonyle en donnant (η 5 -C 5 H 5 ) 2 Ta(CO) HOCHRR') + PF 6 − . En milieu basique, ces sels sont deprotones en (η 5 -C 5 H 5 ) 2 Ta(CO)(OCHRR')

Detailed time-mean measurements have been realized on a transonic axial flow compressor. Flow quantities in the secondary flow regions have been obtained. The purpose of this paper is to present some essential features which drive the secondary following development in axial compressor among others, the strong influence of secondary vortex motion on the energy transfer between the flow and the blading is displayed. Also, we study the effect of tip clearance and axial distance between blade row. A secondary flow model is used for comparisons with theoretical computations. Very good comparisons have been obtained which show the validity of the theoretical model, in particular, the decomposition of the secondary flow into a viscous part and a vortical part, using an inviscid flow as a basis.