Comparison of gait between young adults fitted with the space foot and nondisabled persons

Prosthetic feet having new keel configurations were specially designed to store deformation energy during early and midstance and release it at push-off. These prosthetic components display longitudinal symmetry favoring good energy storage/release capability in the sagittal plane. The need for inverters/everters either as independent components or within the foot structure has long been recognized. This article documents the walking and slow jogging performances of six young adults wearing below-knee prostheses fitted with the Space Foot, a flexible foot prosthesis that provides medio-lateral control at heel-strike and lateral and forward propulsion at push-off. Results indicate that the Space Foot behaves as a flexible keel foot prosthesis. Its gait performances are also good for fast walking; however, the Space Foot's actual design should be modified if used in sporting activities involving running.     

Physiological and biochemical markers in the process of resistance and/or tolerance of heavy metals in the abandoned mining area of Sidi Kamber,Skikda, Algeria

This paper reports the biomonitoring of metallic pollution in the mine of Sidi Kamber Skikda town, to determine the resistance and/or tolerance to Zn, Pb, Cd and Cu in metalliferous plants. During the period of March–May, 2015, soil and plants samples were collected from three different stations in the study area. The total heavy metal fraction was determined by ICP/MS, whereas biochemical markers were determined by spectrophotometric techniques. The results obtained showed high levels of heavy metals in soil and plants compared to international standards. The translocation factor revealed that the studied plants can transfer and/or accumulate metals in their roots or their aerial parts as a function of characteristics of each metal, soil contents and physiological role in the plant. The contents of chlorophyll, proline, total sugars and total proteins are directly influenced by changes in bioavailable contents of heavy metals. It has been found that the plants studied and biomarkers are better suited for phytoremediation and biomonitoring of heavy metals pollution.     

Energy Efficiency Optimization for Wireless Body Area Networks Under 802.15.6 Standard

Wireless Personal Communications - With the attractive applications in e-Health, a booming interest is granted to wireless body area network (WBAN). Through WBAN, healthcare professionals can...     

Kinematic modeling for the assessment of wheelchair user'sstability

A computer kinematic model was developed to simulate the lateral and transverse stabilities of wheelchair users in order to compare the effect of different backrests. This model is composed of ellipsoids and parallelepipeds representing the main components of the human body, the seating devices and the wheelchair. A fifteen-segment three-dimensional (3-D) model linked by spherical and revolute joints was created using the ADAMS software (Mechanical Dynamics, Inc.). Torsional springs and dampers are used at the joints to represent four sets of articulation stiffness. Seating devices are represented with 45 rectangular surface patches. The interface between human body and seating devices is modeled by contact elements, which included the specification of stiffness, damping, and deformation of cushions and buttocks. Simulations of a user and his wheelchair moving at 1.4 m/s on a tilted pathway were performed. Different indexes [trunk lateral tilt (TLT) and trunk transverse rotation (TTR)] were measured and compared to those of a similar experimental study on four subjects. The effect of joint stiffness was quantified and a sensitivity study showed the importance of the hip, neck, lumbar, and thoracic joint stiffness on model response (between 16% and 68%). Two backrests (standard and highly contoured) were tested with the kinematic model and their stability compared. Overall, the coherence between the simulations and the experiments shows that this approach is appropriate to compare various seating devices (maximal difference of 1.3° between the simulated and experimental curves for the intermediate joint stiffness sets). The smallest rotations of the highly contoured backrest (6.3° versus 8.9° for TLT and 3.9° versus 6.7° for TTR) suggest that the contouring of the mid torso is more efficient than the lower torso to provide stability to the wheelchair user. This model is an adequate tool to test and improve the design of seating aids     

Optimization of fluoride removal from brackish water by electrodialysis

The study showed that desired potable water can be easily obtained by electrodialysis from fluoride-rich brackish water. Studies have been performed to defluoridate brackish water containing 3000 ppm of total dissolved solids (TDS) and 3 ppm of fluoride using electrodialysis. The behaviour of water parameters (ion contents, TDS, pH, total hardness) with electrodialysis parameters (duration, flow rate, temperature, voltages) is followed. Optimal operational conditions for obtaining desired potable water have been proposed.     

Biomechanical analysis of legrest support of occupied wheelchairs: comparison between a conventional and a compensatory legrest.

This study was undertaken to investigate the effects of elevating legrest on posture and pressure distribution in a group of ten able-bodied subjects sitting in a manual wheelchair. Two types of legrest were tested: a conventional elevating legrest with a fixed axis of rotation, and a compensatory elevating legrest with a moving axis of rotation. A three-dimensional (3-D) kinematics analysis was carried out to assess body posture simultaneously with pressure measurement data collected at the back, seat, calf and foot supports. The compensatory legrest enables to lengthen foot support as the legrest proclines. This compensation at the knee joint level has a beneficial effect in minimizing pelvic and thigh motion as well as in reducing pressure distribution under seat and foot supports. In contrast, the use of a conventional legrest modifies significantly the subject's posture and induces a substantial increase of 40% on pressure data under ischial tuberosities in procline position. These findings are important for disabled and elderly people who need to elevate their lower leg frequently.     

Adaptive pseudo-noise code acquisition scheme using automatic censoring for DS/SS communication in frequency-selective Rayleigh fading channel

An adaptive pseudo-noise code acquisition scheme based on automatic multipath signal cancellation for mobile communication systems in frequency-selective Rayleigh fading channel is proposed. The proposed system combines a serial strategy and an automatic censored cell-averaging constant false alarm rate (CFAR) detector based on ordered data variability. This system does not require any a priori information about the number of interferences caused by the presence of multipath signals in the reference channel. The mean acquisition time and the detection performances of the proposed processor are evaluated and compared with those of the conventional adaptive acquisition scheme based on fixed-censoring point detector. It is shown that the considered scheme outperforms significantly the conventional one. The effects of various channel parameters on the acquisition performance, namely the number of resolvable paths, the partial correlation length and the signal-to-noise ratio are also investigated.     

Contribution study of properties of copper indium diselenide thin films

Stoichiometric powder of CuInSe₂ (CIS) was prepared from molten stoichiometric quantities of the elements. The structure analyzed by X-ray diffraction powder (XRD), shows mainly the chalcopyrite phase. CIS polycrystalline thin films deposited from this powder have been grown on glass substrates in vacuum by thermal evaporation method. The structural and electrical properties of both as-deposited and annealed films were studied using X-ray diffraction and dark conductivity measurements respectively. As-prepared films at room temperature showed an amorphous structure. However, the chalcopyrite structure with (112) preferential orientation was observed after annealing in vacuum at 400 °C during 30 min. The influence of the annealing process on the dark conductivity of the films was also discussed.     

Study of the properties of CuInSe2 materials prepared from nanoparticle powder

This work studies the properties of CuInSe₂ (CIS) thin films obtained from nanoparticle powder. The samples were prepared by direct thermal evaporation of ball milled powder from a tungsten crucible onto precleaned glass substrates, using a BALZERS coating unit. The as deposited films were annealed in a vacuum at different temperatures. The composition, structure, morphology and optical properties of these samples have been investigated. X-ray diffraction (XRD) results showed that the CuInSe₂ phase may be prepared by mechanical alloying method. The crystallites of the CIS powder were found to be partially copper-rich. The as-deposited film was polycrystalline in nature having chalcopyrite structure as a mainly phase. The surface morphology is homogeneous across the surface. Expected optical properties (E_g = 1.04 eV, α ≈ 10⁴ cm^? 1) and near stoichiometric composition (Cu: 23.62 at.%, In: 24.35 at.% and Se: 52.03 at.%) were determined.     

Bidirectional HMM-based Arabic POS tagging

In this work, we will present a new concept of POS tagging that will be implemented for the Arabic language. Indeed, we will see that in Arabic there are a numerous cases where the determination of the morpho-syntactic state of a word depends on the states of the subsequent words, which represents the theoretical foundation of the approach: how to consider, in addition of the past elements, the future ones. We will then demonstrate how the POS tagging in its statistical application: the HMM, is based mainly on the past elements, and how to combine both direct and reverse taggers to tag the same sequence of words in both senses. Thus, we will propose a hypothesis for the result selecting. In the practical part, we will present, in general, the used resource and the changes made on it. Then we will explain the experiment steps and the parameters collected and presented on graphics, that we will discuss later to lead to the final conclusion.