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Xylanases are widely used enzymes in the food, textile, and paper industries. Most efficient xylanases have been identified from lignocellulose-degrading microbiota, such as the microbiota of the cow rumen and the termite hindgut. Xylanase genes from efficient pulp and paper wastewater treatment (PPWT) microbiota have been previously recovered by metagenomics, assigning most of the xylanase genes to the GH10 family. In this study, a total of 40 GH10 family xylanase genes derived from a certain PPWT microbiota were cloned and expressed in Escherichia coli BL21 (DE3). Among these xylanase genes, 14 showed xylanase activity on beechwood substrate. Two of these, PW-xyl9 and PW-xyl37, showed high activities, and were purified to evaluate their xylanase properties. Values of optimal pH and temperature for PW-xyl9 were pH 7 and 60 ℃, respectively, while those for PW-xyl37 were pH 7 and 55 ℃, respectively; their specific xylanase activities under optimal conditions were 470.1 U/mg protein and 113.7 U/mg protein, respectively. Furthermore, the Km values of PW-xyl9 and PW-xyl37 were determined as 8.02 and 18.8 g/L, respectively. The characterization of these two xylanases paves the way for potential application in future pulp and paper production and other industries, indicating that PPWT microbiota has been an undiscovered reservoir of efficient lignocellulase genes. This study demonstrates that a metagenomic approach has the potential to screen efficient xylanases of uncultured microorganisms from lignocellulose-degrading microbiota. In a similar way, other efficient lignocellulase genes might be identified from PPWT treatment microbiota in the future.

Background Highly comminuted intra-articular fractures are complex and difficult injuries to treat. Once emergent care is rendered, the definitive treatment objective is to restore the original anatomy while minimizing surgically induced trauma. Operations that use limited or percutaneous approaches help preserve tissue vitality, but reduced visibility makes reconstruction more difficult. A pre-operative plan of how comminuted fragments would best be re-positioned to restore anatomy helps in executing a successful reduction.

Paper supports were used to develop a simple, inexpensive, fast and sensitive electrochemical immunosensor for the analysis of antibiotic residues in milk samples, where single-walled carbon nanotubes (SWNTs) and a simple dip-dry coating method were employed to prepare the highly sensitive biosensor. Well-dispersed SWNTs were impregnated with an antibody against neomycin to obtain a composite coating solution, followed by dipping the filtration paper in the solution to fabricate the sensitive biosensor which had high electrical conductivity. Based on the impedance change in the entire paper supported biosensor with increased concentrations of neomycin, the limit detection of the optimized method was 0.04 ng mL(-1) and a linear detection range from 0.2 to 125 ng mL(-1), well below the European Union regulations for neomycin in this matrix. This paper supported biosensor was applied to determine neomycin in milk samples after a simple sample treatment, with spiked recoveries which ranged from 93.25 to 110.47%. A variety of antibiotic residues in milk samples could be determined following similar sensor preparation.

New non-asbestos papers composed of glass fibres and ceramic fibres were examined for dental application. The fibre liners showed a larger deformation ability than conventional asbestos paper, and had a smaller water uptake than the conventional liner. In addition, the setting expansion in new non-asbestos papers was increased at 60 min after investing, similarly to the setting expansion behaviour in a conventional liner. After casting a silver alloy using the new fibre liners, a microstructure mainly of primary solid formed, with a smaller amount of complex phases. The microstructures formed were similar to those in the conventional asbestos liner.

Thoracic endovascular aortic repair (TEVAR) has been accepted as the mainstream treatment for type B aortic dissection, but post-TEVAR biomechanical-related complications are still a major drawback. Unfortunately, the stent-graft (SG) configuration after implantation and biomechanical interactions between the SG and local aorta are usually unknown prior to a TEVAR procedure. The ability to obtain such information via personalised computational simulation would greatly assist clinicians in pre-surgical planning. In this study, a virtual SG deployment simulation framework was developed for the treatment for a complicated aortic dissection case. It incorporates patient-specific anatomical information based on pre-TEVAR CT angiographic images, details of the SG design and the mechanical properties of the stent wire, graft and dissected aorta. Hyperelastic material parameters for the aortic wall were determined based on uniaxial tensile testing performed on aortic tissue samples taken from type B aortic dissection patients. Pre-stress conditions of the aortic wall and the action of blood pressure were also accounted for. The simulated post-TEVAR configuration was compared with follow-up CT scans, demonstrating good agreement with mean deviations of 5.8% in local open area and 4.6 mm in stent strut position. Deployment of the SG increased the maximum principal stress by 24.30 kPa in the narrowed true lumen but reduced the stress by 31.38 kPa in the entry tear region where there was an aneurysmal expansion. Comparisons of simulation results with different levels of model complexity suggested that pre-stress of the aortic wall and blood pressure inside the SG should be included in order to accurately predict the deformation of the deployed SG.

Motile human-skin fibroblasts form macroscopic swirling patterns when grown to confluence on a culture dish. In this paper, we investigate the effect of coating the culture-dish surface with collagen on the resulting pattern, using human-skin fibroblast NB1RGB cells as the model system. The presence of the collagen coating is expected to enhance the adherence of the fibroblasts to the dish surface, and thereby also enhance the traction that the fibroblasts have as they move. We find that, contrary to our initial expectation, the coating does not significantly affect the motility of the fibroblasts. Their eventual number density at confluence is also unaffected. However, the coherence length of cell orientation in the swirling pattern is diminished. We also find that the fibroblasts cultured in a collagen-coated dish are rounder in shape and shorter in perimeter, compared to those cultured in an uncoated dish. We hypothesize that the rounder cell-shape which weakens the cell-cell nematic contact interaction is responsible for the change in coherence length. A simple mathematical model of the migrating fibroblasts is constructed, which demonstrates that constant motility with weaker nematic interaction strength does indeed lead to the shortening of the coherence length., to appear in J. of Biological Physics

Critical-sized bone defects are critical healing conditions that, if left untreated, often lead to non-unions. To reduce the risk, critical-sized bone defects are often treated with recombinant human BMP-2. Although enhanced bone tissue formation is observed when BMP-2 is administered locally to the defect, spatial and temporal distribution of callus tissue often differs from that found during regular bone healing or in defects treated differently. How this altered tissue patterning due to BMP-2 treatment is linked to mechano-biological principles at the cellular scale remains largely unknown. In this study, the mechano-biological regulation of BMP-2-treated critical-sized bone defect healing was investigated using a multiphysics multiscale in silico approach. Finite element and agent-based modeling techniques were combined to simulate healing within a critical-sized bone defect (5 mm) in a rat femur. Computer model predictions were compared to in vivo microCT data outcome of bone tissue patterning at 2, 4, and 6 weeks postoperation. In vivo, BMP-2 treatment led to complete healing through periosteal bone bridging already after 2 weeks postoperation. Computer model simulations showed that the BMP-2 specific tissue patterning can be explained by the migration of mesenchymal stromal cells to regions with a specific concentration of BMP-2 (chemotaxis). This study shows how computational modeling can help us to further understand the mechanisms behind treatment effects on compromised healing conditions as well as to optimize future treatment strategies. ispartof: BIOMECHANICS AND MODELING IN MECHANOBIOLOGY vol:20 issue:4 pages:1627-1644 ispartof: location:Germany status: published

Ammonia is used as a fertilizer for agriculture, chemical raw material, and carrier for transporting hydrogen, and with economic development, the demand for ammonia has increased. The Haber–Bosch process, which is the main method for producing ammonia, can produce ammonia with high efficiency. However, since it consumes a large amount of fossil energy, it is necessary to develop an alternative method for producing ammonia with less environmental impact. Ammonia production from food by-products is an appealing production process owing to unused resource usage, including waste, and mild reaction conditions. However, when food by-products and biomass are used as feedstocks, impurities often reduce productivity. Using metabolic profiling, glucose was identified as a potential inhibitor of ammonia production from impure food by-products. We constructed the recombinant Escherichia coli, in which glucose uptake was reduced by ptsG gene disruption and amino acid catabolism was promoted by glnA gene disruption. Ammonia production efficiency from okara, a food by-product, was improved in this strain; 35.4 mM ammonia was produced (47% yield). This study might provide a strategy for efficient ammonia production from food by-products.

Precise control of drug release from nanoparticles can improve efficacy and reduce systemic toxicity associated with administration of certain medications. Here, we combined two phenomena, photothermal conversion in plasmon resonant gold coating and thermal sensitivity of liposome compositions, to achieve a drug delivery system that rapidly releases doxorubicin in response to external stimulus. Methods: Thermosensitive liposomes were loaded with doxorubicin and gold-coated to produce plasmon resonant drug delivery system. Plasmon resonance facilitates release of contents upon near-infrared laser illumination, thus providing spatial and temporal control of the process. This controlled delivery system was compared to thermosensitive liposomes without gold coating and to the FDA-approved Doxil that was gold-coated to create a plasmon resonant coating. Release of doxorubicin from the gold-coated thermosensitive liposomes was further confirmed by tests of cell viability. Results: Upon laser illumination at 760 nm and 88 mW/cm2 power density, permeability of plasmon resonant liposomes increased by three orders of magnitude, from 70×10-12 to 60,000x10-12 cm/s. In control experiments, mild hyperthermia (42°C) increased permeability of these thermosensitive liposomes to just 3,700×10-12 cm/s. Neither hyperthermia nor laser illumination elicit content release from Doxil or plasmon resonant Doxil obtained by gold coating. Laser-induced release of doxorubicin from plasmon resonant thermosensitive liposomes resulted in the loss of cell viability significantly greater than in any of the control groups. Conclusion: Combination of thermosensitive liposomes with plasmon resonant coating enables rapid, controlled release, not currently available in pharmaceutical formulations of anticancer drugs.

The mechanical characterization of brain tissue is a complex task that scientists have tried to accomplish for over 50 years. The results in the literature often differ by orders of magnitude because of the lack of a standard testing protocol. Different testing conditions (including humidity, temperature, strain rate), the methodology adopted, and the variety of the species analysed are all potential sources of discrepancies in the measurements. In this work, we present a rigorous experimental investigation on the mechanical properties of human brain, covering both grey and white matter. The influence of testing conditions is also shown and thoroughly discussed. The material characterization performed is finally adopted to provide inputs to a mathematical formulation suitable for numerical simulations of brain deformation during surgical procedures.

The first carpometacarpal (CMC) joint, located at the base of the thumb and formed by the junction between the first metacarpal and trapezium, is a common site for osteoarthritis of the hand. The shape of both the first metacarpal and trapezium contributes to the intrinsic bony stability of the joint, and variability in the morphology of both these bones can affect the joint’s function. The objectives of this study were to quantify the morphological variation in the complete metacarpal and trapezium and determine any correlation between anatomical features of these two components of the first CMC joint. A multi-object statistical shape modelling pipeline, consisting of scaling, hierarchical rigid registration, non-rigid registration and projection pursuit principal component analysis, was implemented. Four anatomical measures were quantified from the shape model, namely the first metacarpal articular tilt and torsion angles and the trapezium length and width. Variations in the first metacarpal articular tilt angle (− 6.3° θ $${\fancyscript{w}}$$ w α θ $$\text{ }\ell$$ ℓ

A detailed investigation of nanostructured iron oxides/(oxy)hydroxides gathered after cultivation of bacteria from the genus Leptothrix as iron (II) oxidizers is presented. A specific type of medium is selected for the cultivation of the bacteria. Results for sediment powder and bio-film on glass substrate samples from the same media are discussed. XRD, Raman spectroscopy, SEM, and TEM images and PPMS measurements are used to prove the exact composition of the biogenic products and to interpret the oxidation process. Analysis of the data collected shows that around 80 % of the iron (II) from the growth medium has been transformed into iron (III) in the form of different (oxy)hydroxides, with the rest found to be in a mixed 2,5 valence in magnetite. Our investigation shows that the bio-film sample has a phase content different from that of the powdered biomass and that lepidocrocite (γ-FeOOH) is the predominant and the initial biogenic phase in both samples. Magnetite nanoparticles are a secondary product in the bio-film, part of which possesses a defective quasi-maghemite surface layer. In the powdered biomass, the oxidation steps are not fully completed. The initial products are non-stoichiometric and due to the mixed ferric and ferrous ions present, they develop into: (i) lepidocrocite (γ-FeOOH) as a basic sediment, (ii) magnetite (Fe3O4) and (iii) goethite (α-FeOOH) in small quantities. The average size of all iron-bearing particles is found to be below 30 nm. The magnetic measurements performed show a superparamagnetic behavior of the material at room temperature.

Background: Anthropogenic nanoparticles (NPs) have found their way into many goods of everyday life. Inhalation, ingestion and skin contact are potential routes for NPs to enter the body. In particular the digestive tract with its huge absorptive surface area provides a prime gateway for NP uptake. Considering that NPs are covered by luminal gut-constituents en route through the gastrointestinal tract, we wanted to know if such modifications have an influence on the interaction between NPs and enterocytes.Results: We investigated the consequences of a treatment with various luminal gut-constituents on the adherence of nanoparticles to intestinal epithelial cells. Carboxylated polystyrene particles 20, 100 and 200 nm in size represented our anthropogenic NPs, and differentiated Caco-2 cells served as model for mature enterocytes of the small intestine. Pretreatment with the proteins BSA and casein consistently reduced the adherence of all NPs to the cultured enterocytes, while incubation of NPs with meat extract had no obvious effect on particle adherence. In contrast, contact with intestinal fluid appeared to increase the particle-cell interaction of 20 and 100 nm NPs.Conclusion: Luminal gut-constituents may both attenuate and augment the adherence of NPs to cell surfaces. These effects appear to be dependent on the particle size as well as on the type of interacting protein. While some proteins will rather passivate particles towards cell attachment, possibly by increasing colloid stability or camouflaging attachment sites, certain components of intestinal fluid are capable to modify particle surfaces in such a way that interactions with cellular surface structures result in an increased binding.

As the domains, in which robots operate change the objects a robot may be required to grasp and manipulate, are likely to vary significantly and often. Furthermore there is increasing likelihood that in the future robots will work collaboratively alongside people. There has therefore been interest in the development of biologically inspired robot designs which take inspiration from nature. This paper presents the design and testing of a variable stiffness, three fingered soft gripper, which uses pneumatic muscles to actuate the fingers and granular jamming to vary their stiffness. This gripper is able to adjust its stiffness depending upon how fragile/deformable the object being grasped is. It is also lightweight and low inertia, making it better suited to operation near people. Each finger is formed from a cylindrical rubber bladder filled with a granular material. It is shown how decreasing the pressure inside the finger increases the jamming effect and raises finger stiffness. The paper shows experimentally how the finger stiffness can be increased from 21 N·m−1 to 71 N·m−1. The paper also describes the kinematics of the fingers and demonstrates how they can be position-controlled at a range of different stiffness values.

This paper reviews the field of feedback control for neuroprosthesis systems that restore advanced standing function to individuals with spinal cord injury. Investigations into closed-loop control of standing by functional neuromuscular stimulation (FNS) have spanned three decades. The ultimate goal for FNS standing control systems is to facilitate hands free standing and enabling the user to perform manual functions at self-selected leaning positions. However, most clinical systems for home usage currently only provide basic upright standing using preprogrammed stimulation patterns. To date, online modulation of stimulation to produce advanced standing functions such as balance against postural disturbances or the ability to assume leaning postures have been limited to simulation and laboratory investigations. While great technological advances have been made in biomechanical sensing and interfaces for neuromuscular stimulation, further progress is still required for finer motor control by FNS. Another major challenge is the development of sophisticated control schemes that produce the necessary postural adjustments, adapt against accelerating muscle fatigue, and consider volitional actions of the intact upper-body of the user. Model-based development for novel control schemes are proven and sensible approaches to prototype and test the basic operating efficacy of potentially complex and multi-faceted control systems. The major considerations for further innovation of such systems are summarized in this paper prior to describing the evolution of closed-loop FNS control of standing from previous works. Finally, necessary emerging technologies to for implementing FNS feedback control systems for standing are identified. These technological advancements include novel electrodes that more completely and selectively activate paralyzed musculature and implantable sensors and stimulation modules for flexible neuroprosthesis system deployment.

This paper reports self-assembled multi-component hybrid hydrogels including a range of nanoscale systems and characterizes the extent to which each component maintains its own unique functionality, demonstrating that multi-functionality can be achieved by simply mixing carefully-chosen constituents., This paper reports self-assembled multi-component hybrid hydrogels including a range of nanoscale systems and characterizes the extent to which each component maintains its own unique functionality, demonstrating that multi-functionality can be achieved by simply mixing carefully-chosen constituents. Specifically, the individual components are: (i) pH-activated low-molecular-weight gelator (LMWG) 1,3;2,4-dibenzylidenesorbitol-4′,4′′-dicarboxylic acid (DBS–COOH), (ii) thermally-activated polymer gelator (PG) agarose, (iii) anionic biopolymer heparin, and (iv) cationic self-assembled multivalent (SAMul) micelles capable of binding heparin. The LMWG still self-assembles in the presence of PG agarose, is slightly modified on the nanoscale by heparin, but is totally disrupted by the micelles. However, if the SAMul micelles are bound to heparin, DBS–COOH self-assembly is largely unaffected. The LMWG endows hybrid materials with pH-responsive behavior, while the PG provides mechanical robustness. The rate of heparin release can be controlled through network density and composition, with the LMWG and PG behaving differently in this regard, while the presence of the heparin binder completely inhibits heparin release through complexation. This study demonstrates that a multi-component approach can yield exquisite control over self-assembled materials. We reason that controlling orthogonality in such systems will underpin further development of controlled release systems with biomedical applications.

Abnormal protein concentration levels in human body fluids, such as urine, serum etc., are considered to associate with disease states, providing essential information for the pre-clinical diagnosis. This paper presents a wireless immunoglobulin-coated magnetoelastic (ME) biosensor for fast, cost-effective detections of human serum albumin (HSA) with small sample volumes at a microliter scale. This is the first portable resonant sensor based on magnetostrictive effect that can monitor different molecular states of HSA. Anti-HSA Immunoglobulin G (IgG) was immobilized on the surface of the ME sensor to selectively capture HSA. The rapid conjugation between the antibody and antigen changed the sensor surface states and thus induced resonance frequency shifts (RFS), which were monitored in real time for the qualitative and quantitative analysis of HSA. This paper brings forward a System on Chip (SoC)-based system architecture to realize the function of RFS sampling. The performance of the portable device was validated to be comparable to that of the Vector Network Analyzer (VNA) AV3620 using different concentrations of HSA solution. The RFS were linearly proportional to the HSA concentrations in the range from 0.1 to 100 μg/mL with a linearity up to 0.998, a sensitivity of 8.70 Hz/μg.mL-1 and a detection limit of 0.039 μg/mL, indicating good feasibility of this method. Meanwhile, the response of this portable ME biosensor was quick and specific to HSA targets. This ME biosensor shows high potential to be used in diagnosing abnormal HSA.

Biological systems, in general, represent a special type of control system. The physiological processes of homeostasis, which serve to maintain the organism&rsquo, s internal equilibrium against external influences, are clear forms of biological control system. An example of the homeostasis is the control of the organism thermal state or the thermoregulation. The thermoregulatory control of human skin blood flow, via vasoconstriction and vasodilation, is vital to maintaining normal body temperatures during challenges to thermal homeostasis such as localised cooling. The main objective of this paper is to reverse engineer the localised thermoregulatory cold-induced vasoconstriction/vasodilation (CIVC/CIVD) reactions using a data-based mechanistic approach. Two types of localised cooling were applied to the fingers of 33 healthy participants, namely, continuous and intermittent cooling. Modelling of the thermoregulatory cold-induced vasoconstriction/vasodilation reactions suggested two underlying processes, with one process being 10 times faster. A new term is suggested in this paper, namely, the latent heat of CIVD, which represents the amount of dissipated heat required to trigger the CIVD. Moreover, a new model for the thermoregulatory localised CIVC/CIVD reactions is proposed. The suggested new model states that, with an initial vasodilation state, the initial localised CIVC is triggered based on a certain threshold in the rate of heat dissipation from the skin to the surrounding environment.

The optimization of scientific communication depends, at least in part, on the elimination of linguistic obstacles and ambiguous prose [1]. The ability to communicate scientific information effectively is an essential skill to have as a scientist but also as a tool to popularize scientific knowledge for the public [2]. Acronyms and abbreviations in scientific manuscripts may help attain some aspects in this important endeavor for example to avoid cumbersome repetitions, save space, and speed up the reading flow of a manuscript. However, the overuse of abbreviations and acronyms may also hamper the reading process and render the written text cryptic. As there is no strict guideline or obligation for authors to use or not to use acronyms, many authors are tempted to misuse abbreviations, including in titles and abstracts of their manuscripts, particularly when they try to introduce new ones. However, the use of abbreviations and acronyms in scientific writing is not mandatory or even necessary [3]. Although some journals ask authors to provide abbreviations’ lists, such lists are often placed at the beginning of the main text, obliging readers to scroll up/down or to turn pages forward/backward many times to recall the meaning of an abbreviation they encounter far in the text. Repetitive scrolling or back/forth movements could thus overwhelm the reader, especially when the abbreviations are many, ambiguous or unfamiliar. Scientific papers should not be boring [4] but the overuse of abbreviations and acronyms may render the reading of potentially worthwhile papers boring rather than appealing. In the same way that we need to teach more effectively [5], we also need to communicate written texts more efficiently without verbosity, vague or complex abbreviations. To avoid the troublesome use of abbreviations, and to be effective and digestible, scientific manuscripts need to be written in a clear and direct style without ambiguous or complex abbreviations or acronyms. An easily comprehensible text should be preferable over an excessive use of uncommon abbreviations or acronyms. Journals may need to set up clear rules to limit the use of abbreviations that should be tolerated only if the abbreviation itself is short, easy to memorize, common, or if the full name is overly long. An effective science communication needs to be clear to be rewarding [6]. It might also be good to adopt a standardized terminology [7]. To relay complex scientific concepts more efficiently, it would be useful to offer formal and consistent training early in the career of scientists to improve their communication skills with the public and with other non-specialist scientists [8]. It should also be unnecessary to create new equivocal abbreviations or acronyms for each new expression or concept introduced in new studies. Moreover, as publications are now produced electronically, space saving is no longer an issue to write full sentences rather than cryptic and uncommon abbreviations [3]. The use of uncommon acronyms excessively is indeed one of many other common practices that should be avoided in the scientific manuscripts [9]. For the sake of good reading and comprehension of scientific papers, clarity should prevail on brevity. Much of the scientific information is already and inherently complex. The overuse of abbreviations and acronyms will add a new layer of complexity and convolution that could be easily avoided by simple attention and care to avoid enigmatic proses and abbreviations. & Khaled Moustafa khaled.moustafa@gmail.com

In recent years the combined use of functional electrical stimulation (FES) and robotic devices, called hybrid robotic rehabilitation systems, has emerged as a promising approach for rehabilitation of lower and upper limb motor functions. This paper presents a review of the state of the art of current hybrid robotic solutions for upper limb rehabilitation after stroke. For this aim, studies have been selected through a search using web databases: IEEE-Xplore, Scopus and PubMed. A total of 10 different hybrid robotic systems were identified, and they are presented in this paper. Selected systems are critically compared considering their technological components and aspects that form part of the hybrid robotic solution, the proposed control strategies that have been implemented, as well as the current technological challenges in this topic. Additionally, we will present and discuss the corresponding evidences on the effectiveness of these hybrid robotic therapies. The review also discusses the future trends in this field., This work was supported by the Spanish Ministry of Economy and Competitiveness (projects HYPER-CSD2009-00067 CONSOLIDER-INGENIO 2010, DPI2011-25892, DGA-FSE).

Functional electrical stimulation has been shown to be a safe and effective means of correcting foot 12 drop of central neurological origin. Current surface-based devices typically consist of a single channel stimulator, 13 a sensor for determining gait phase and a cuff, within which is housed the anode and cathode. The cuff-mounted 14 electrode design reduces the likelihood of large errors in electrode placement, but the user is still fully responsible 15 for selecting the correct stimulation level each time the system is donned. Researchers have investigated different 16 approaches to automating aspects of setup and/or use, including recent promising work based on iterative learning 17 techniques. This paper reports on the design and clinical evaluation of an electrode array-based FES system for 18 the correction of drop foot, ShefStim. The paper reviews the design process from proof of concept lab-based study, 19 through modelling of the array geometry and interface layer to array search algorithm development. Finally, the 20 paper summarises two clinical studies involving patients with drop foot. The results suggest that the ShefStim 21 system with automated setup produces results which are comparable with clinician setup of conventional systems. 22 Further, the final study demonstrated that patients can use the system without clinical supervision. When used 23 unsupervised, setup time was 14 minutes (9 minutes for automated search plus 5 minutes for donning the 24 equipment), although this figure could be reduced significantly with relatively minor changes to the design.

In the process of improvement of prosthetic devices, there have been efforts to develop satisfactorily working artificial hands but still lots of work is to be done to meet the accuracy and requirements of the human hand movement. The EMG signal has been most promising signal in development of artificial limbs. The present review paper gives the historical developments in three main sections. First part describes the EMG signal properties. Second part deals with the mathematical models developed till now for EMG signal analysis. In the third part different design approaches have been reviewed for artificial hand. First approach discussed here is on the body-powered terminal devices which are controlled by the user's pull on the control cable to open the hand or hook and for the grip strength. Other being myoelectric controls type, an externally-powered system which uses electrical impulses, generated by contraction of the amputees own remaining muscles to operate a motor in a mechanical hand, hook or elbow. This paper presents a brief overview of above mentioned issues with regard to artificial hands.

International audience; This paper presents a new accelerometer based method for estimating the posture of a subject standing on a dynamic perturbation platform. The induced perturbation is used to study the control mechanisms as well as the balance requirements that regulate the upright standing. These perturbations are translated into different intensity levels of speed and acceleration along longitudinal and lateral directions of motion. In our method, the human posture is modeled by a tridimensional, three-segment inverted pendulum which simultaneously takes into account both the anterior–posterior and medio-lateral strategies of hip and ankle. Four tri-axial accelerometers are used her, one accelerometer is placed on the platform, and the other three are attached to a human subject. Based on the results, the joint angle estimated compare closely to measurements from magnetic encoders placed on an articulated arm joint. The results were also comparable to those found when using a high-end optical motion capture system coupled with advanced biomechanical simulation software. This paper presents the comparisons of our accelerometer-based method with encoder and optical marker based method of the estimated joint angles under different dynamics perturbations.

This paper describes the measurement and reconstruction of the leaflet geometry for a pericardial heart valve. Tasks involved include mapping the leaflet geometries by laser digitizing and reconstructing the 3D freeform leaflet surface based on a laser scanned profile. The challenge is to design a prosthetic valve that maximizes the benefits offered to the recipient as compared to the normally operating naturally-occurring valve. This research was prompted by the fact that artificial heart valve bioprostheses do not provide long life durability comparable to the natural heart valve, together with the anticipated benefits associated with defining the valve geometries, especially the leaflet geometries for the bioprosthetic and human valves, in order to create a replicate valve fabricated from synthetic materials. Our method applies the concept of reverse engineering in order to reconstruct the freeform surface geometry. A Brown & Shape coordinate measuring machine (CMM) equipped with a HyMARC laser-digitizing system was used to measure the leaflet profiles of a Baxter Carpentier-Edwards ® pericardial heart valve. The computer software, Polyworks was used to pre-process the raw data obtained from the scanning, which included merging images, eliminating duplicate points, and adding interpolated points. Three methods, creating a mesh model from cloud points, creating a freeform surface from cloud points, and generating a freeform surface by B-splines are presented in this paper to reconstruct the freeform leaflet surface. The mesh model created using Polyworks can be used for rapid prototyping and visualization. To fit a freeform surface to cloud points is straightforward but the rendering of a smooth surface is usually unpredictable. A surface fitted by a group of B-splines fitted to cloud points was found to be much smoother. This method offers the possibility of manually adjusting the surface curvature, locally. However, the process is complex and requires additional manipulation. Finally, this paper presents a reverse engineered design for the pericardial heart valve which contains three identical leaflets with reconstructed geometry.

This paper provides an overview of forward dynamic neuromusculoskeletal modeling. The aim of such models is to estimate or predict muscle forces, joint moments, and/or joint kinematics from neural signals. This is a four-step process. In the first step,muscle activation dynamicsgovern the transformation from the neural signal to a measure of muscle activation—a time varying parameter between 0 and 1. In the second step,muscle contraction dynamicscharacterize how muscle activations are transformed into muscle forces. The third step requires a model of themusculoskeletal geometryto transform muscle forces to joint moments. Finally, theequations of motionallow joint moments to be transformed into joint movements. Each step involves complex nonlinear relationships. The focus of this paper is on the details involved in the first two steps, since these are the most challenging to the biomechanician. The global process is then explained through applications to the study of predicting isometric elbow moments and dynamic knee kinetics.

Light therapy is increasingly administered and studied as a non-pharmacologic treatment for a variety of health-related problems, including treatment of people with dementia. Light therapy comes in a variety of ways, ranging from being exposed to daylight, to being exposed to light emitted by light boxes and ambient bright light. Light therapy is an area in medicine where medical sciences meet the realms of physics, engineering and technology. Therefore, it is paramount that attention is paid in the methodology of studies to the technical aspects in their full breadth. This paper provides an extensive introduction for non-technical researchers on how to describe and adjust their methodology when involved in lighting therapy research. A specific focus in this manuscript is on ambient bright light, as it is an emerging field within the domain of light therapy. The paper deals with how to (i) describe the lighting equipment, (ii) describe the light measurements, (iii) describe the building and interaction with daylight. Moreover, attention is paid to the uncertainty in standards and guidelines regarding light and lighting for older adults.

[EN] Breast augmentation surgery is a widespread practice for aesthetic purposes. Current techniques, however, are not able to reliably predict the desired final aspect of the breast after the intervention, whose success relies almost completely on the surgeon's skill. In this way, patient-specific methodologies capable of predicting the outcomes of such interventions are of particular interest. In this paper, a finite element biomechanical model of the breast of a female patient before an augmentation mammoplasty was generated using computer tomography images. Prosthesis insertion during surgery was simulated using the theory of finite elasticity. Hyperelastic constitutive models were considered for breast tissues and silicone implants. The deformed geometry obtained from finite element analysis was compared qualitatively and quantitatively with the real breast shape of the patient lying in supine position, with root-mean-squared errors less than 3. mm. The results indicate that the presented methodology is able to reasonably predict the aspect of the breast in an intermediate step of augmentation mammoplasty, and reveal the potential capabilities of finite element simulations for visualization and prediction purposes. However, further work is required before this methodology can be helpful in aesthetic surgery planning. © 2011 IPEM., The support of Instituto de Salud Carlos III (ISCIII) through the CIBER initiative, and the support of Platform for Biological Tissue Characterization of the Centro de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN) are highly appreciated. The translation of this paper was funded by the Universitat Politecnica de Valencia, Spain.

This paper reports investigations led on the combination of the refractive index and morphological dilation to enhance performances towards breast tumour margin delineation during conserving surgeries. The refractive index map of invasive ductal and lobular carcinomas were constructed from an inverse electromagnetic problem. Morphological dilation combined with refractive index thresholding was conducted to classify the tissue regions as malignant or benign. A histology routine was conducted to evaluate the performances of various dilation geometries associated with different thresholds. It was found that the combination of a wide structuring element and high refractive index was improving the correctness of tissue classification in comparison to other configurations or without dilation. The method reports a sensitivity of around 80% and a specificity of 82% for the best case. These results indicate that combining the fundamental optical properties of tissues denoted by their refractive index with morphological dilation may open routes to define supporting procedures during breast-conserving surgeries.

The Oxford Rig was designed for biomechanical testing of post-mortem human knee-joint specimens during simulated flexed-knee stance, such as occurs when riding a bicycle, rising from a chair, or climbing stairs. It has been asserted, but never proven, that the movements of the ‘ankle’ and ‘hip’ assemblies of the Oxford Rig combine to allow a knee specimen its natural six degrees-of-freedom of movement (6 d.o.f.). This paper investigates this claim mathematically using the general mobility criterion for spatial linkages and the basics of screw theory. It is shown that within the physiological range of knee-joint movement and the physical construction of the Rig, the knee specimen is allowed full spatial freedom (6 d.o.f.). The general approach used in this paper could also be applied to the analysis and, in particular, to the design of other rigs used for biomechanical testing of post-mortem human joint specimens.