An electromechanical swing-phase-controlled prosthetic knee joint for conversion of physiological energy to electrical energy: feasibility study

Microprocessor-controlled prostheses facilitate a more natural and efficient gait for individuals with above-knee amputations by continually adjusting the level of swing-phase damping. One caveat associated with these technologies is that the user must charge the onboard batteries on a daily basis. It is, therefore, the aim of this study to examine the feasibility of using an electromechanical system to provide prosthetic swing-phase damping and, concomitantly, the function of converting physiological energy that is normally dissipated during the swing phase, to electrical energy. Gait data from a single subject and data from a kinematic simulator were used to develop an empirical model. The findings in this study indicate that an electromagnetic system has appropriate characteristics for use in swing-phase control and also has the potential to recover energy under particular conditions.     

Femtosecond laser synthesis of bimetallic Pt-Au nanoparticles

Bimetallic Pt-Au nanoparticles were successfully synthesized by irradiating the metal precursor solution with high intensity femtosecond laser. The intense optical field created by femtosecond laser pulse induced the production of highly charged ions and molecules due to the optical decomposition of metal precursor molecules. Further collisions with molecules result in subsequent growth of the nuclei and codeposition of Pt and Au atoms on the nuclei to form the larger ones. The method is a simple, easy-to-control and environmentally benign process. The average size and morphology of bimetallic nanoparticles were examined by transmission electron microscope. The compositional distributions of Pt and Au of individual Pt-Au nanoparticles were examined by X-ray energy dispersive spectroscopy (EDS).     

Effect of alternate night nocturnal home hemodialysis on anemia control in patients with end‐stage renal disease

Nocturnal home hemodialysis (NHHD) has shown promising results in various clinical parameters. Whether NHHD provide benefit in anemia management remains controversial. This study aims to investigate whether anemia and erythropoiesis‐stimulating agent (ESA) requirement are improved in patients receiving alternate night NHHD compared with conventional hemodialysis (CHD). In this retrospective controlled study, a clinical data of 23 patients receiving NHHD were compared with 25 in‐center CHD patients. Hemoglobin level, ESA requirement, iron profile, and dialysis adequacy indexes were compared between the two groups. Hemoglobin level increased from baseline of 9.37 ± 1.39 g/dL to 11.34 ± 2.41 g/dL at 24 months (P < 0.001) and ESA requirement decreased from 103.44 ± 53.55 U/kg/week to 47.33 ± 50.62 U/kg/week (P < 0.001) in NHHD patients. ESA requirement further reduced after the first year of NHHD (P = 0.037). Standard Kt/V increased from baseline of 2.02 ± 0.28 to 3.52 ± 0.30 at 24 months (P < 0.001). At 24 months, hemoglobin level increased by 1.98 ± 2.74 g/dL in the NHHD group while it decreased by 0.20 ± 2.32 g/dL in the CHD group (P = 0.007). ESA requirement decreased by 53.49 ± 55.50 U/kg/week in NHHD patients whereas it increased by 16.22 ± 50.01 U/kg/week in CHD patients (P < 0.001). Twenty‐six percent of NHHD patients were able to stop ESA compared with none in the CHD group. Standard Kt/V showed greater increase in the NHHD group. (1.49 ± 0.36 in NHHD vs. 0.18 ± 0.31 in CHD, P = 0.005). NHHD with an alternate night schedule improves anemia and reduces ESA requirement as a result of enhanced uremic clearance. This benefit extended beyond the first year of NHHD.     

Improvement in intestinal function and health by the peel fibre derived from Citrus sinensis L cv Liucheng

The water‐insoluble fibre‐rich fraction (WIFF) was isolated from the peel of Citrus sinensis L cv Liucheng in an economical way. The influences of a WIFF‐containing diet on the intestinal function and health in hamsters were investigated and compared with those of cellulose‐added and fibre‐free diets. Our results showed that the inclusion of WIFF in a fibre‐free diet might result in some significant improvements in serum, intestinal, caecal and faecal parameters, such as elevated serum alkaline phosphatase activity (127%), increased intestinal maltase and sucrase activities (180 and 164% respectively), decreased caecal pH (6.30), reduced caecal and faecal ammonia contents (by 25.4 and 34.1% respectively) and decreased activities of faecal β‐D ‐glucosidase (by 48.1%), β‐D ‐glucuronidase (by 52.9%) and urease (by 81.5%). These results suggested that the incorporation of WIFF in the diet at a level of 50 g kg^?1 might exert a favourable effect on intestinal function and health. Accordingly, WIFF could be exploited as a potential functional ingredient in human diets and also offer industries an opportunity to develop new formulations of fibre‐rich functional foods. Copyright © 2005 Society of Chemical Industry     

Design, Modeling, and Analysis of a Brushless Doubly Fed Doubly Salient Machine for Electric Vehicles

This paper presents a new three-phase 12/8-pole brushless doubly fed doubly salient (BDFDS) machine for application to electric vehicles. It consists of two types of stator windings-polyphase armature winding and DC field winding. The key is to design, model, and analyze the proposed BDFDS machine. The output power equation is derived analytically, and the initial calculation of machine dimensions and parameters are also discussed. When we use finite-element analysis, the field distributions of the BDFDS machine at different loads and field currents are obtained, in which magnetic saturation and armature reaction are considered. Static characteristics of the proposed machine are also obtained. Based on these characteristics, the system mathematical model can be established. Hence, the evaluation of system performance is conducted by computer simulation. A 12/8-pole BDFDS machine is designed and built for experimentation. Experimental results are given to verify the theoretical analysis and simulation.     

The Trade-Off Between Performance and Security of Virtualized Trusted Execution Environment on Android

Nowadays, with the significant growth of the mobile market, security issues on the Android Operation System have also become an urgent matter. Trusted execution environment (TEE) technologies are considered an option for satisfying the inviolable property by taking advantage of hardware security. However, for Android, TEE technologies still contain restrictions and limitations. The first issue is that non-original equipment manufacturer developers have limited access to the functionality of hardware-based TEE. Another issue of hardware-based TEE is the cross-platform problem. Since every mobile device supports different TEE vendors, it becomes an obstacle for developers to migrate their trusted applications to other Android devices. A software-based TEE solution is a potential approach that allows developers to customize, package and deliver the product efficiently. Motivated by that idea, this paper introduces a VTEE model, a software-based TEE solution, on Android devices. This research contributes to the analysis of the feasibility of using a virtualized TEE on Android devices by considering two metrics: computing performance and security. The experiment shows that the VTEE model can host other software-based TEE services and deliver various cryptography TEE functions on the Android environment. The security evaluation shows that adding the VTEE model to the existing Android does not add more security issues to the traditional design. Overall, this paper shows applicable solutions to adjust the balance between computing performance and security.     

Functional Graphene for Peritumoral Brain Microenvironment Modulation Therapy in Glioblastoma

Peritumoral brain invasion is the main target to cure glioblastoma. Chemoradiotherapy and targeted therapies fail to combat peritumoral relapse. Brain inaccessibility and tumor heterogeneity explain this failure, combined with overlooking the peritumor microenvironment. Reduce graphene oxide (rGO) provides a unique opportunity to modulate the local brain microenvironment. Multimodal graphene impacts are reported on glioblastoma cells in vitro but fail when translated in vivo because of low diffusion. This issue is solved by developing a new rGO formulation involving ultramixing during the functionalization with polyethyleneimine (PEI) leading to the formation of highly water-stable rGO-PEI. Wide mice brain diffusion and biocompatibility are demonstrated. Using an invasive GL261 model, an anti-invasive effect is observed. A major unexpected modification of the peritumoral area is also observed with the neutralization of gliosis. In vitro, mechanistic investigations are performed using primary astrocytes and cytokine array. The result suggests that direct contact of rGO-PEI_UT neutralizes astrogliosis, decreasing several proinflammatory cytokines that would explain a bystander tumor anti-invasive effect. rGO also significantly downregulates several proinvasive/protumoral cytokines at the tumor cell level. The results open the way to a new microenvironment anti-invasive nanotherapy using a new graphene nanomaterial that is optimized for in vivo brain delivery.