Abstract 3D force sensors have been proven its effectiveness and appropriateness for robotics applications. It has been used in medical and physical therapy applications such as surgical robot and Instrument Assisted Soft Tissue Manipulation (IASTM) in the recent times. The 3D force sensors have been utilized in robot assisted surgeries and modern physical therapy devices to monitor the 3D forces for improved performances. The 3D force sensor performance and specifications depend on different design parameters, such as structural configuration, sensing elements placements, and load criterion. In this paper, different bioinspired structure configurations have been investigated and analyzed to obtain the optimal 3D force sensor configuration in terms of structural integrity, compactness, safety factor, and strain sensitivity. Finite Element Analysis (FEA) simulation was used for the analysis to minimize the time of the development cycle.

Abstract Lung supportive devices are widely used for non-invasive positive airway pressure ventilation and respiratory therapy to help provide breathing support for patients with various lung diseases including Obstructive Sleep Apnea. These devices deliver air to the patient through a facial or nasal mask, and the use of these devices normally results in dryness in the upper airways. However, the exhaled air consists of very high humidity content hence the moisture content of this air can be reused in the inhalation process. This research focuses on testing clinically a previously developed element which can recover the moisture from the exhaled air and use it for re-inhalation. 21 healthy volunteers between the ages of 21 and 55, where 38.1% were females and 61.9% males, were invited to participate in this study. The results show a viable element which is able to trap water molecules from the expiration airflow and release them into the inspiration airflow.

Abstract This work outlines the positive-intrinsic-negative diode fabrication process for a Miniaturized Fast Neutron Detector and documents alpha source testing of a single positive-intrinsic-negative diode. The Miniaturized Fast Neutron Detector provides information about the kinetic energy distribution of neutrons with resolution up to 20 MeV and has 1–2% of the volume of comparable current state-of-the-art neutron spectrometers, namely Bonner Ball Neutron Detector sets and Capture-Gated Neutron Scintillator Detectors. The Miniaturized Fast Neutron Detector can be used to estimate neutron doses for heavy charged particle therapy patients improving the understanding of secondary cancer risks, monitor secondary neutron radiation more efficiently in therapy treatment facilities, and perform an important role in protecting astronauts from radiation.

Abstract Virtual reality (VR) is a great new technology which has extensive applications, and it is imperative that there is a way to use VR comfortably. This will allow VR to become an everyday tool, creating a more interactive world. With more VR integration new technologies can be created and allow VR to expand further into fields like therapy or military training. However, VR comes with some unfortunate side effects. The cybersickness that many people experience when using a VR system has been shown to trigger a thermoregulatory response that causes sweating, the sensation of being excessively hot, as well as nausea. These symptoms of cybersickness make it uncomfortable to use a VR system for any long period of time. In order to combat this, the authors present a device which can effectively cool the user to extend the time duration a user can comfortably use a VR system.

Radiative-thermal models of light transport in tissue are presented that stimulates the thermal effects of pulsed laser radiation on very thin scattering and absorbing biological layers. Thermal therapies require a firm understanding of temperature-depth relationship for tissue modification or destruction, especially through very thin layers that are characterized by contrasting opto-thermal properties. Temperature distribution in biological layers of thicknesses in the order of their mean free path or less are evaluated before the onset of thermal diffusion for both the traditional model of Monte Carlo simulation and that with new features tailored for very thin layers. Temperature dynamics in very thin layers such as skin in dermatology is a typical example. For instance, during the heating of small volumes of tissue as in fractional photothermolysis, nonablative dermal remodeling and ablative skin resurfacing, short pulse lasers are used by choosing pulse length sufficiently short that will not damage the surrounding healthy tissue, but sufficiently long enough to allow damage, necrosis or coagulation over the entire target area. This is in contrast to the situation where thermal dissipation due to heat conduction is the principal determinant of tissue damage. Numerical results obtained from both models differ significantly. While the model designed specifically for very thin scattering layers tends to confine temperature rise to specific layers, the traditional model have a tendency to misjudge the layers of interest thereby giving rise to temperature increase in undesired locations. These results will advance our understanding of radiation transport in layers that are extremely very thin, and help develop better treatment modules for laser therapeutic treatment regimes in surgery and dermatology.

In the United States, Alzheimer’s disease (AD) affects one in ten people ages 65 and older. In most patients, the first indication of AD is the inability to remember new information, and symptoms grow to include behavior changes and increasing confusion and suspicions surrounding loved ones and daily events. As the disease progresses, the cortex and hippocampus regions of the brain decrease in size, allowing the fluid-filled ventricles within the brain to increase. New and innovative therapies to delay the onset of the disease and progression of the symptoms are being discovered. For example, the antibody solanezumab is undergoing clinical trials to determine its ability to reduce the levels of beta-amyloid in the brain, a known risk factor of AD. Consequently, the ability to identify patients who could benefit from the therapies will be invaluable. The purpose of this study is to determine if the digital volume correlation (DVC) algorithm can detect and track the onset and progression of AD using magnetic resonance imaging (MRI) scans of the head. DVC measures the deformation and strain of the volumetric MRI dataset by tracking the changes in its grey value pattern. A collection of MRI datasets of a patient’s head, which include scans from a baseline visit and visits at 6 months, 12 months, and every 12 months thereafter, is used in our analysis. A strain is applied to each set of MRI scans prior to implementation of the digital volume correlation algorithm. The DVC algorithm is then applied to the dataset and the resulting error between the expected and calculated strain is computed. A decrease in the contrast of the MRI dataset will correlate to additional error by the algorithm. As a result, an increase in the calculated strain error is anticipated to correlate with an increase in the ventricles in the brain, or progression of the disease, over the time period of interest.

Patellofemoral pain syndrome (PFPS) is a musculoskeletal condition characterized by anterior knee pain. The symptoms associated with PFPS can be further aggravated through activities that increase patellofemoral compressive forces. Despite the number of mechanisms that are considered to contribute to this disorder, there is no consensus about its etiology, causing difficulty in prescribing the appropriate treatment or physical therapy. To properly evaluate PFPS, the influences of various muscles and their geometries on knee joint reaction forces for a human subject during a normal gait cycle were observed by conducting parametric analysis using OpenSim. The muscles that were seen to be most critical and have a potential effect in reducing the pain experienced at the knee joint are the soleus, iliopsoas, and gastrocnemius muscles. It was observed that individually increasing the length of the soleus and iliopsoas muscles from 75% to 125% of their default lengths resulted in decrease in knee joint reaction forces of up to 400 N (57%) in the x-direction and 600 N (40%) in the y-direction for the soleus and 550 N (38%) in the x-direction and 1000 N (29%) in the y-direction for the iliopsoas. It was also seen that by indirectly reducing the cross-sectional area of the gastrocnemius muscles from 125% to 75% of their default value resulted in decreases in knee joint reaction forces of up to 250 N (50%) in the x-direction and 500 N (42%) in the y-direction. Therefore, exercises should be advised to specifically stretch or strengthen the soleus and iliopsoas, and the gastrocnemius muscles should be rested. Pain and recovery time may be substantially reduced with the utilization of a targeted physiotherapy treatment plan. It can be coupled with longterm physiotherapy program for improving muscle fitness.

In the clinical application, the mechanical stimulation against the damaged brain tissue is adopted as the kinesitherapy for the nerve regeneration. Nevertheless, the fundamental mechanism to repair the damaged nerve cell has not been revealed yet. Recently, the cyclic stretch stimulation has been reported as the efficacious treatment method to enhance the axonal extension for regenerative therapy of injured nerve cell. Therefore, we try to develop a new cellular automaton (CA) finite element (FE) hybrid method to predict the axonal extension and nerve network generation, which can evaluate the effect of stretch stimulation on the cell body, axon and dendrites. In the FE results, the stress concentration occurred at the junction of the axon and cell body. The maximum stress value in the axon was 8.2 kPa which is about twice as large as that of the cell body. CA adopted to predict the morphological evolution of nerve cells under the mechanical stimulation. It was confirmed that the stress affects to accelerate the axonal extension as experimentally suggested. As a result, our CAFE can be employed to simulate the axonal extension and generation of nerve network system under the condition of extra cellular mechanical stimulation.

Intravascular treatment is known as one of effective treatment methods for cerebral aneurysms. One problem of this therapy is that an intravascular treatment device unexpectedly moves and a tip of the device strongly contacts on a vessel wall. This unexpected movement of the device causes vascular injury. In actual treatment, 2D X-ray image is used. It is difficult for an operator to estimate 3D position of the device from the 2D X-ray image. In this study, we propose estimation methods for 3D position of devices using a X-ray image and a 3D blood vessel model. At the first step of estimation procedure, a 3D position of X-ray image, a 3D blood vessel model and X-ray source (Xs) are determined by 2D/3D registration method. The actual 3D position of the device tip (P) is placed on the straight line between Xs and P. Moreover, its position is limited within the 3D vessel model. From characteristics, the 3D position of the device tip is estimated. In this study, two methods to estimate the 3D position of the device are proposed. First: A closest point to the straight line from the center line of the blood vessel model is defined as the position in 3D space of the guidewire (one-point estimation method). Second: A mean value of points on the straight line inside the blood vessel model is defined as the position in 3D space of the guidewire (average estimation method). The accuracy of estimation methods depends on angle of X-ray irradiation. In this study, the relationship between the accuracy of estimation methods and the angle of X-ray irradiation. The estimation accuracy was investigated using numerical calculation. In the case of a simple blood vessel shape, the error of the estimation was proportional to the angular difference between an ideal and an actual. The errors of the estimated arc length parameter at the ideal angle of X-ray irradiation were 0.002 mm and 0.078 mm, respectively. This result shows that this method is effective for simple blood vessel shape. In future work, other factors to affect the accuracy are also investigated.

Magnetic Seizure therapy (MST) is emerging as a treatment for patients suffering from severe depression where an induced current due to an external electromagnetic field is employed. This procedure can only be considered effective when sufficient induced current activates the neurons in the prefrontal cortex. Computer simulation of MST is essential to provide better insight of this procedure and to supplement the clinical trials. To this end, an understanding of transmission of electric impulse through the nerve is considered essential. Stochastic impulse spike sequences are trigged when membrane potential crosses a threshold value. Quantitative numerical predictions employing a mathematical model and induced current defined via Ornstein Uhlenbeck (OU) process predict that both the linear steady-state and rectified models provide adequate threshold adaptation while the rectified model exhibits superior spiking behavior. The present study when combined with suitable numerical simulation of electromagnetic induction is envisaged to aid the MST clinical treatment.

Successful outcomes from the use of orthodontic devices are underpinned on their effective anchorage and the loading that they apply to the underlying facial structures. Anchorage plays an important role in determining the point of application of the corrective forces and subsequently the orientation of the resultant of these forces, which in-turn governs the outcome of treatment. Therefore, patient-specific design of anchors and their placement may benefit significantly from personalization using patient-specific and three-dimensional (3D) cephalometry. 3D cephalometry is therefore a first step to personalization of orthodontic treatment. In this feasibility study, we demonstrate the viability a novel image processing and surface analysis pipeline to quantify facial symmetry about the mid-sagittal facial plane, which may offer insight into optimal placement and orientation for implantation of orthodontic anchors, starting with patient-specific cone beam computed tomography (CBCT) images. Typical assessments of geometrical features/attributes of face include size, position, orientation, shape, and symmetry. Using 3D CBCT images in the DICOM image format, skull images were first segmented using a basic iso-contouring approach. To quantify symmetry, we split the skull along the mid-sagittal plane and used an iterative closest point (ICP) approach in order to rigidly co-register the left and right sides of the skull, optimizing for rotation, translation and scaling, after reflection of one half across the mid-sagittal plane. This was accomplished using an in-house plugin is developed for the open-source visualization toolkit (VTK) based 3D visualization tool, Paraview (Kitware Inc.). Finally, using a signed regional distance mapping plugin we were able to assess the regional asymmetry of regions of the skull (e.g. upper and lower jaw – specific targets for therapy) using colormaps of regional asymmetry (in terms of left-v/s-right side surface distance) and visualized the same as vector glyphs. The direction of these vectors is synonymous with anticipated regional forces required in order to achieve left-right symmetry, which in-turn may have value in surgical planning for orthodontic implantation. In sum, we demonstrate a workflow for computer-aided cephalometry to assess the symmetry of the skull, which shows promise for personalized orthodontic anchor design.

Lung supportive devices (LSD) are widely used for respiratory ventilation and therapy to help provide breathing support for patients with various lung diseases including Obstructive Sleep Apnea. These devices deliver air to the patient through a nasal or facial mask, and the use of these devices normally results in dryness in the upper airways. However, the exhaled air consists of very high humidity content. The question raised, is it possible to recover some of the moisture content of this air to reuse in the inhalation process. This research focuses on developing an element which can recover the moisture from the exhaled air and the possibility of using it for re-inhalation. The main component is made up of a fibrous cotton fabric polymerized with Poly (N-isopropylacrylamide) (PNIPAM) and sewed with a resistor filament to control the temperature. The results show a viable element which is able to trap water molecules from the expiration airflow and release them into the inspiration airflow.

Shirodhara is an ayurveda therapy treating subjects for stress (depression/anxiety/hypertension) insomnia, headache and several kinds of psychosis. When there is a fluid impact on a solid surface, a transient impact will be developed at the interface in short time duration as vibration on forehead. The fluid impact of the liquid falling from the beaker at controlled flow rate is measured using an integrated circuit piezoelectric (ICP) force sensor for various tapping condition. The time-dependent response of the sensor is acquired using data acquisition system which is connected to the computer. The force is determined by measuring the voltage output from the piezoelectric force sensor. The impact experiment is done for single droplet, intermittent flow of drops and continuous flow of liquid falling from a fixed height of 7.5 cm. From the results, we observe the impact force for each fluid have a subtle variation depending on the falling condition and impact velocity of the fluid falling from a height.

A cast is used to encase a limb or part of the body to stabilize and hold anatomical structures in place to allow healing of broken bones and ligament tears by promoting immobilization. Conventional orthopedic casts have been made out of Plaster of Paris or fiberglass since ages. The traditional plaster casts have a wide range of problems that have been long since evaded due to the lack of a better alternative. Ever since the advent of additive manufacturing, many remarkable things have been made possible by the technology of 3D printing. The Exoskeletal Immobilizer is a custom 3D printed orthopedic cast that is well ventilated, light weighted, aesthetically pleasing and anatomically accurate. Even though printing the immobilizer on spot takes a little longer than the conventional cast, its countless benefits make up for the waiting time. It is extremely logical and useful for the ones suffering from cerebral palsy, who are forced to wear casts for their entire life. This project is not just another profit making business idea but is the cornerstone that is being laid to serve the people better and lead humanity into the next phase of medical advancement. By integrating parts of physiotherapy, eastern medicine, orthopedics and latest technologies, the Immobilizer promises a speedy recovery. The possibility of performing ultrasound therapy, electrical stimulation therapy, chromotherapy, cryotherapy and acupuncture therapy during the immobilization period reduces the healing time at least by about 40% [4] and eases discomfort of the patients. The features imparted to the cast have been specially handpicked and researched to provide a safe overlap of post immobilization treatment and the immobilization period to facilitate faster healing. The Exoskeletal Immobilizer can not only heal the fracture or a tear faster but can also keep the patient comfortable during the treatment.

Intravascular ultrasound approach has shown its advantages for thrombectomy. Catheter-directed ultrasound techniques have realized safe therapies by suppressing mechanical contact and penetration of excessive ultrasound energy through the tissue. One limitation of this approach is the lack of the sufficient ultrasound energy for fast thrombectomy because typical catheter-mounted transducers have high-frequency and low acoustic power. In this work, we aim to resolve this problem by designing miniaturized focused ultrasound transducers for improved therapeutic efficacy, which can generate low-frequency, sufficient pressure output within the confined insonation beam. This study builds upon our previous initial design of sub-megahertz, forward-looking, focused ultrasound transducers for preliminary in vitro study on microbubble-mediated thrombolysis. 650 kHz, forward-looking, concave-aperture ultrasound transducers were designed and mounted on 5–6 F catheters. The effect of design factors including aperture diameter, radius-of-curvature, and concave lens acoustic impedance on focusing performance were analyzed by using finite element analysis. Although the theoretical prerequisites for ideal beam focusing were not fulfilled due to the spatial limitation, the simulation results showed that practical design of the concave lens with the small geometrical aperture still enables to generate confined beam with a reasonable focal gain. Experimental validation results confirmed that the focal gain of 9 dB can be achievable. The measured transmitting sensitivity of the concave aperture transducer is 22.5 kPa/V pp .

Magnetic seizure therapy (MST) is currently on trial as an alternative to Electro-convulsive therapy (ECT) to treat patients suffering from treatment resistant depression (TRD). This paper is concerned with developing a deeper understanding of the mechanics behind MST by employing finite element analysis (FEA) of brain. To this end, a model that consists of concentric spherical layers that represent a realistic anatomical head model has been employed. Simulations performed via COMSOL Multi-physics helped identify the dimensions and coil types for the MST device as well as the angular probing orientations. Largest induced current due to the externally imposed magnetic field was found in the cerebrospinal fluid (CSF), which act as a barrier to induce current in the gray matter. Different copper coil configurations were experimented with namely the cap coil, stacked coil and the multi-stacked coil. These studies are envisaged to provide a quantitative approach to virtually simulate the MST procedure and hence enhance the benefits clinical trials that are currently underway.

Objective: In clinical treatment, ash cleaning is an effective way to enhance the thermal efficiency of moxibustion. Understanding the thermal characteristics of moxibustion therapy with ash cleaning is necessary to improve its clinical efficiency. Method: Temperature distributions of burning moxa sticks were measured with an infrared camera. The moxa burning duration was set at 20min with different ash cleaning cycles (3min, 4min, 5min and no ash cleaning). A moxa stick burning model with ash cleaning was built to analyze the detailed burning discipline and compared with experimental results. In addition, temperature distributions of in-vitro tissue during moxibustion with different ash cleaning cycles were obtained using thermocouples and infrared camera. Results: Ash cleaning has effectively extended the high-temperature areas of moxa sticks and accelerated the burning velocity. Shorter ash cleaning cycle led to higher average temperature of moxa sticks. The simulated results agreed well with experimental data, which indicates that the moxa stick burning model with ash cleaning is reliable to reveal the burning discipline of moxa sticks. For in-vitro tissue, ash cleaning induced obvious temperature rise at tissue surface and slight rise in deep tissue. Compared with 3 min and 5 min, the ash cleaning cycle of 4 min is the recommended value.

This paper presents the design and analysis of a portable forearm exoskeleton designed for rehabilitation and assistive purposes (FE.RAP). The design uses a direct-drive mechanism to actuate three degrees of freedom (DOFs) of the wrist, including: (1) wrist flexion and extension, (2) wrist radial and ulnar deviation, and (3) forearm supination and pronation. In recent decades, automated at-home recovery therapies have emerged as popular alternatives to hospital-based rehabilitation. Often in the case of lower arm rehabilitation, however, existing exoskeletons are not practical to use as home rehabilitation devices due to being non-transportable, bulky in size, and heavy in weight. In addition, compact sized exoskeletons often lack sufficient DOFs to mirror the natural movements of the hand. This paper proposes a design that addresses the drawbacks of current exoskeletons. The FE.RAP is designed to be portable and lightweight, while maintaining sufficient DOFs to help patients recover the range of motion needed by the wrist and forearm to support activities of daily living (ADL). Along with the design, the paper presents an analysis used to optimize the workspace for each DOF of the system. A kinematic analysis is performed to validate and compare the workspace of the system, as well as the coupling relationship between the DOFs, to that of the human hand and wrist. Finally, the torque required to support most ADLs is determined using static and dynamic analyses.

During spaceflight, the loss of mechanical loads due to microgravity leads to rapid bone loss, where bone deteriorates at a rate of 1–2% per month, where some astronauts can lose as much as 20% of their skeletal mass in a single expedition [NASA, 2001]. In order to prevent muscle and bone loss, long-term space flight exercise regimes are strictly implemented [Shackleford, 2004]. Current research has demonstrated that mechanical vibrations can help to maintain or improve bone mass [Chan, 2013] and reduce adiposity [Chen, 2015, Sen, 2011] when signals are applied at the appropriate frequency and amplitude. We have developed an acoustic sound chamber that can apply sound waves to stem cells grown in vitro. Characterization of the culture conditions inside the vibration chamber showed considerable variance across the culture plates where an applied acceleration of 0.6g varied at different spots in a 12-well tissue culture plate from as low as 0.47g to 0.78g. We believe the variance is caused by differences in the rigidity of the culture plates that makes the waves transmit inconsistently through the plastic. We hypothesized acoustic waves would induce osteogenic differentiation when applied to stem cells. We utilized pre-osteoblastic stem cells (MC3T3-E1-Subclone 4) to observe the effects of acoustic waves when applied at 0.3g and 0.6g, compared to non-vibrated controls. Cells were vibrated for 30 minutes a day for either 6 days (n = 24/group) or 12 days (n = 12/group). Cellular changes were characterized by assessing well-by-well cell number by a manual cell count and mineral content by Alizarin Red S staining. Differences between groups were determined using One-Way ANOVA with a post hoc test: Student’s t-test. To assess the effects of the variance across the culture plates, correlative analysis was conducted for well-by-well variation using Regression Analysis. Acoustically vibrated wells had 10x more cells after 6 days and showed more mineralization than non-vibrated wells at both 6 and 12 days. Acoustic waves have the ability to increase cell proliferation and can drive stem cell differentiation towards an osteoblastic lineage, this could lead to therapies that prevent bone loss during spaceflight.

The development of gene therapies, small molecules and nanoparticle-based therapeutics in pharmacology have prompted the need for parenteral administration as they possess limited bioactivity, low stability, high specificity and potency. The ability to directly deliver drugs to a specific area offers the capability of minimized required drug quantity, localization of exposure, and limited systemic side effects. Currently, there is no standard for the creation of implantable devices to monitor health status and provide therapeutic treatment. We explored the applications and uses for carbon nanotube based arrays for in vivo drug delivery, specifically as an implantable reusable mode of delivery. The increased availability of 3D printing allows for not only the rapid and reproducible fabrication of designs, but also the ability to incorporate these carbon nanotube arrays in ways that are not feasible using traditional machining methods. These techniques offer the means to design and fabricate a reservoir on carbon nanotube arrays to create a loadable reservoir that can regulate flow, dispensing cargo for mass cellular injection. This research focuses primarily on the development of an attachable drug reservoir for these devices and looks to explore the possibilities of designing reservoirs made out of biocompatible 3D printed materials such as plastics, alloys, or bioceramics. We explored several routes, including a rigid and semi-rigid, as well as how each design impacted the flow through the membrane.