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Currently, many researchers are working on stock price prediction system by using deep learning algorithms. Stock market is completely random, and there is no pattern. Even though, a pattern in stock market could be found, it will not be last for a long time because the stock market will adopt a new situation and the strategy is no longer available on already changed stock market. There are many auto trading programs such as a trading bot on stock market. However, they are literally trade stocks based on human’s direction or rules. It will not affect any changes, and it keeps working as what rules are set up from the initial status on the stock market. Stock price depends on volume of total sales, stock news, revenue, total asset, big buyer’s position and so on. There are many aspects for affecting stock price, and it changes all the time. Therefore, it keeps monitoring stock market and makes a decision whether buy or sell at the right time for earning profits. This research uses Bidirectional Long Short-Term Memory (BLSTM) to predict stock price in the near future. BLSTM is more accurate than LSTM which is one directional. In addition, stock market is like a living creature. Data to manipulate stock price must be inputted and analyzed consistently. Therefore, stock price can be predicted by consistent monitoring with BLSTM.

Background Duplication 15q (Dup15q) syndrome is a rare neurogenetic disorder characterized by autism and pharmacoresistant epilepsy. Most individuals with isodicentric duplications have been on multiple medications to control seizures. We recently developed a model of Dup15q in Drosophila by elevating levels of fly Dube3a in glial cells using repo-GAL4, not neurons. In contrast to other Dup15q models, these flies develop seizures that worsen with age. Methods We screened repo>Dube3a flies for approved compounds that can suppress seizures. Flies 3 to 5 days old were exposed to compounds in the fly food during development. Flies were tested using a bang sensitivity assay for seizure recovery time. At least 40 animals were tested per experiment, with separate testing for male and female flies. Studies of K+ content in glial cells of the fly brain were also performed using a fluorescent K+ indicator. Results We identified 17 of 1280 compounds in the Prestwick Chemical Library that could suppress seizures. Eight compounds were validated in secondary screening. Four of these compounds regulated either serotonergic or dopaminergic signaling, and subsequent experiments confirmed that seizure suppression occurred primarily through stimulation of serotonin receptor 5-HT1A. Additional studies of K+ levels showed that Dube3a regulation of the Na+/K+ exchanger ATPα (adenosine triphosphatase α) in glia may be modulated by serotonin/dopamine signaling, causing seizure suppression. Conclusions Based on these pharmacological and genetic studies, we present an argument for the use of 5-HT1A agonists in the treatment of Dup15q epilepsy.

Rapidly proliferating cells produce more ribosomes to translate sufficient proteins for cell growth. One of the first and rate limiting steps in translation initiation is the interaction of the small ribosomal subunit with mRNAs. Therefore, effective small ribosomal subunit biogenesis is critical for translation initiation efficiency. Here we report the identification of the zinc finger protein 692 (ZNF692), a MYC-induced nucleolar scaffold that coordinates the final steps in the biogenesis of the small 40S ribosome. ZNF692 forms a complex with rRNA, the 90S processome and the nucleolar exosome in the granular component of the nucleolus creating a hub specialized in the final steps of 18S processing and small ribosomal subunit maturation. Cancer cells are more reliant on ZNF692 for increased translation than normal cells. We propose that MYC increases translation efficiency by promoting the expression of ZNF692, adjusting the translation rate to the increase in mRNA transcription induced by MYC.

PARP1 inhibitors (PARPi) are known to kill tumor cells via two mechanisms (PARP1 catalytic inhibition and PARP1 trapping). The relative contribution of these two pathways in mediating the cytotoxicity of PARPi, however, is not well understood. Here we designed a series of small molecule PARP degraders. Treatment with one such compound iRucaparib-AP6 results in highly efficient and specific PARP1 degradation. iRucaparib-AP6 blocks the enzymatic activity of PARP1 in vitro, and PARP1-mediated poly-ADP-ribosylation signaling in intact cells. This strategy mimics PARP1 genetic depletion, which enables the pharmacological decoupling of PARP1 inhibition from PARP1 trapping. Finally, by depleting PARP1, iRucaparib-AP6 protects muscle cells and primary cardiomyocytes from DNA-damage-induced energy crisis and cell death. In summary, these compounds represent 'non-trapping' PARP1 degraders that block both the catalytic activity and scaffolding effects of PARP1, providing an ideal approach for the amelioration of the various pathological conditions caused by PARP1 hyperactivation.

Glioblastoma is the most common and aggressive type of cancer in the brain; its poor prognosis is often marked by reoccurrence due to resistance to the chemotherapeutic agent temozolomide, which is triggered by an increase in the expression of DNA repair enzymes such as MGMT. The poor prognosis and limited therapeutic options led to studies targeted at understanding specific vulnerabilities of glioblastoma cells. Metabolic adaptations leading to increased synthesis of nucleotides by de novo biosynthesis pathways are emerging as key alterations driving glioblastoma growth. In this study, we show that enzymes necessary for the de novo biosynthesis of pyrimidines, DHODH and UMPS, are elevated in high grade gliomas and in glioblastoma cell lines. We demonstrate that DHODH’s activity is necessary to maintain ribosomal DNA transcription (rDNA). Pharmacological inhibition of DHODH with the specific inhibitors brequinar or ML390 effectively depleted the pool of pyrimidines in glioblastoma cells grown in vitro and in vivo and impaired rDNA transcription, leading to nucleolar stress. Nucleolar stress was visualized by the aberrant redistribution of the transcription factor UBF and the nucleolar organizer nucleophosmin 1 (NPM1), as well as the stabilization of the transcription factor p53. Moreover, DHODH inhibition decreased the proliferation of glioblastoma cells, including temozolomide-resistant cells. Importantly, the addition of exogenous uridine, which reconstitutes the cellular pool of pyrimidine by the salvage pathway, to the culture media recovered the impaired rDNA transcription, nucleolar morphology, p53 levels, and proliferation of glioblastoma cells caused by the DHODH inhibitors. Our in vivo data indicate that while inhibition of DHODH caused a dramatic reduction in pyrimidines in tumor cells, it did not affect the overall pyrimidine levels in normal brain and liver tissues, suggesting that pyrimidine production by the salvage pathway may play an important role in maintaining these nucleotides in normal cells. Our study demonstrates that glioblastoma cells heavily rely on the de novo pyrimidine biosynthesis pathway to generate ribosomal RNA (rRNA) and thus, we identified an approach to inhibit ribosome production and consequently the proliferation of glioblastoma cells through the specific inhibition of the de novo pyrimidine biosynthesis pathway., Author summary The current standard therapy for glioblastoma, the most malignant brain tumor, was established more than a decade ago and relies on a combination of surgery, radiation, and the DNA methylating agent temozolomide. Here, we report a new approach to target glioblastoma growth through the inhibition of the de novo biosynthesis of pyrimidines, which preferentially limits ribosomal RNA (rRNA) production. Cancer cells have elevated rates of rRNA synthesis so that they can produce enough ribosomes to meet the demands for protein synthesis that are linked to increase cell growth and division. Therefore, targeting aberrant rRNA production by reducing nucleotide availability could provide an effective strategy to treat glioblastoma and, potentially, other tumor types.

Duplication 15q syndrome (Dup15q) is a rare neurogenetic disorder characterized by autistic features and difficult to control (pharmacoresistant) epileptic seizures. Most individuals with isodicentric (idic15) have been on multiple medications to control their seizures and some are still seizing after years of treatment. We recently developed a model of Dup15q in Drosophila by elevating levels of fly Dube3a in glial cells, not neurons. Unlike other Dup15q models, these flies develop seizures that worsen as flies age. Here we used this new model to screen for previously approved compounds from the Prestwick Chemical Library which are able to suppress seizures in flies over-expressing Dube3a in glia using the pan glial driver repo-GAL4. We identified 17 out of 1280 compounds in the library that could suppress a bang sensitive (seizure) phenotype. Eight of these compounds were able to suppress seizures significantly in both males and females by at least 50%. Half of these strong seizure suppressors regulated either serotoninergic or dopaminergic signaling and subsequent experiments confirmed that seizure suppression occurs through stimulation of serotonin receptor 5-HT1A but can be further suppressed with the addition of L-Dopa (Levodopa). We provide further support for a seizure model where Dube3a regulation of the Na+/K+ exchanger ATPα in glia can also be modulated by serotonin/dopamine signaling. Finally, based on these pharmacological and genetic studies, we present an argument for the use of 5-HT1A agonists in the treatment of Dup15q epilepsy.

BACKGROUND: Duplication 15q syndrome (Dup15q) is a rare neurogenetic disorder characterized by autism and pharmacoresistant epilepsy. Most individuals with isodicentric (idic15) have been on multiple medications to control seizures. We recently developed a model of Dup15q in Drosophila by elevating levels of fly Dube3a in glial cells using repo-GAL4, not neurons. Unlike other Dup15q models, these flies develop seizures that worsen with age. METHODS: We screened repo>Dube3a flies for approved compounds which can suppress seizures. 3–5 day old flies were exposed to compounds in the fly food during development. Flies were tested using a bang sensitivity assay for seizure recovery time. At least 40 animals were tested per experiment, with separate testing for males and females. Studies of K+ content in glial cells of the fly brain were also performed using a florescent K+ indicator. RESULTS: We identified 17 out of 1280 compounds in the Prestwick Chemical Library could suppress seizures. Eight compounds were validated in secondary screening. Four of these compounds regulated either serotoninergic or dopaminergic signaling and subsequent experiments confirmed that seizure suppression occurs primarily through stimulation of serotonin receptor 5-HT(1A). Additional studies of K+ levels showed that Dube3a regulation of the Na(+)/K(+) exchanger ATPα in glia may be modulated by serotonin/dopamine signaling, causing seizure suppression. CONCLUSIONS: Based on these pharmacological and genetic studies, we present an argument for the use of 5-HT(1A) agonists in the treatment of Dup15q epilepsy.

Upper Limb Rehabilitation Robots (ULRR) for the patient having shoulder and elbow joint movement disorders, requires further study for development. One aspect that must be fulfilled by such robots, is the need to handle uncertainties due to biomechanical variation of different patients, without significantly degrading performance. Currently, rehabilitation robots require re-tuning of controller gain for each individual. This is time consuming process and requires expert training. To overcome this problem, we propose robust sliding mode control algorithm, which uses very basic information of subject like weight, height, age and gender to handle these model uncertainties. For analysis, we have compared our proposed algorithm with Robust Computed Torque Control (RCTC) and Boundary Augmented Sliding Mode Control (BASMC) algorithms with diverse subjects. Results describe the superiority of the proposed algorithm in handling uncertain parameters human arm and robot without degrading the performance.

Upper limb assist exoskeleton robot requires quantitative techniques to assess human motor function and generate command signal for robots to act in compliance with human motion. To asses human motor function, we present Desired Motion Intention (DMI) estimation algorithm using Muscle Circumference Sensor (MCS) and load cells. Here, MCS measures human elbow joint torque using human arm kinematics, biceps/triceps muscle model and physiological cross sectional area of these muscles whereas load cells play a compensatory role for the torque generated by shoulder muscles as these cells measure desire of shoulder muscles to move the arm and not the internal activity of shoulder muscles. Furthermore, damped least square algorithm is used to estimate Desired Motion Intention (DMI) from these torques. To track this estimated DMI, we have used passivity based adaptive control algorithm. This control techniques is particular useful to adapt modeling error of assist exoskeleton robot for different subjects. Proposed methodology is experimentally evaluated on seven degree of freedom upper limb assist exoskeleton. Results show that DMI is well estimated and tracked for assistance by the proposed control algorithm.

In this study, we developed a wearable robot operating on the external skeleton to support the movements of a weak person’s upper limbs, mainly 3-degree of freedom (DOF) of the shoulder, 1-degree of freedom of the elbow. Moreover, we applied a redundant degree of freedom to design an upper extremities wearable robot that accurately follows the movement of the upper limbs. Namely, we applied 4 driving parts to the robot to enable 3-degree of freedom for shoulders by optimizing the conformance between the links and body movement range. The optimal design which minimizes error where the robot and the body is adjusted, improves wear sensation and signal input. We attached a multi-axes load-cell to generate motion intent signals detecting the movements of the body. According to the EMG signal measurements when moving the upper limbs with the robot on, the RMS value decreased compared to that without the robot. This is due to the decrease in muscle activity, which results from using smaller muscular strength. That is to say, when comparing the same movements, the person wearing the robot used less muscular strength with the help of the robot. Also through SEF50 analysis of the EMG signals, we were able to verify that the muscle fatigue lessened.

Conventional gait rehabilitation requires at least three therapists in a traditional rehabilitation training program. Several robots have been developed to reduce human burden and increase rehabilitation efficacy. In this study, we present a lower-limb wearable robot (WA-H) for gait rehabilitation of hemiplegia patients, and propose a protocol of 12 weeks gait rehabilitation training program using WA-H. To identify the efficacy of the robot and protocols, we conducted a clinical study with two actual hemiplegia patients and observed a chronological change of ambulation ability through four assessments. We discovered the progression of results by 6 minute walking test, TUGT (Timed Up and Go Test), SPPB (Short Physical Performance Battery), BBS (Berg Balance Test), and Fugl-Meyer score. The torques generated in the normal side and paralyzed side of the patient became similar, indicating rehabilitation. The result also showed the walking of the paralysis patient improved and imbalance motion had considerable improved performance.

The need for human body posture robots has led researchers to develop dexterous design of exoskeleton robots. Quantitative techniques to assess human motor function and generate commands for robots were required to be developed. In this paper, we present a passivity based adaptive control algorithm for upper limb assist exoskeleton. The proposed algorithm can adapt to different subject parameters and provide efficient response against the biomechanical variations caused by subject variations. Furthermore, we have employed the Particle Swarm Optimization technique to tune the controller gains. Efficacy of the proposed algorithm method is experimentally demonstrated using a seven degree of freedom upper limb assist exoskeleton robot. The proposed algorithm was found to estimate the desired motion and assist accordingly. This algorithm in conjunction with an upper limb assist exoskeleton robot may be very useful for elderly people to perform daily tasks.

Polyketides and nonribosomal peptides are two important types of natural products that are produced by many species of bacteria and fungi but are exceedingly rare in metazoans. Here, we elucidate the structure of a hybrid polyketide-nonribosomal peptide from Caenorhabditis elegans that is produced in the canal-associated neurons (CANs) and promotes survival during starvation-induced larval arrest. Our results uncover a novel mechanism by which animals respond to nutrient fluctuations to extend survival.

This study compares the gait of chronic ambulatory hemiplegic elderly (HE) with those of non-hemiplegic elderly (NHE) using Vicon® 512 motion analysis system to track movement trajectories. Subjects walked with self-selected gait speeds while temporal, spatial, and kinematic variables were analyzed. HE showed significantly decreased walking speed, cadence, stride length, and step length, and increased stride time, step time, and double limb support periods in comparison with NHE. Double limb support of stance phase was significantly increased in HE. In HE, affected pelvis showed marked upward elevation from terminal stance to mid swing phase, and greater external rotation than the NHE (p

Caenorhabditis elegans produces ascaroside pheromones to control its development and behavior. Even minor structural differences in the ascarosides have dramatic consequences for their biological activities. Here, we identify a mechanism that enables C. elegans to dynamically tailor the fatty-acid side chains of the indole-3-carbonyl (IC)-modified ascarosides it has produced. In response to starvation, C. elegans uses the peroxisomal acyl-CoA synthetase ACS-7 to activate the side chains of medium-chain IC-ascarosides for β-oxidation involving the acyl-CoA oxidases ACOX-1.1 and ACOX-3. This pathway rapidly converts a favorable ascaroside pheromone that induces aggregation to an unfavorable one that induces the stress-resistant dauer larval stage. Thus, the pathway allows the worm to respond to changing environmental conditions and alter its chemical message without having to synthesize new ascarosides de novo. We establish a new model for biosynthesis of the IC-ascarosides in which side-chain β-oxidation is critical for controlling the type of IC-ascarosides produced., eLife digest Small roundworms such as Caenorhabditis elegans release chemical signals called ascarosides in order to communicate with other worms of the same species. Using the ascarosides, the worm can tell its friends, for example, how crowded the neighborhood is and whether there is enough food. The ascarosides thus help the worms in the population decide whether the neighborhood is good – meaning they should hang around, eat, and make babies – or whether the neighborhood is bad. If so, the worms should develop into a larval stage specialized for dispersal that will allow them to find a better neighborhood. Roundworms make the ascarosides by attaching a long chemical ‘side chain’ to an ascarylose sugar. Further chemical modifications allow the worms to produce different signals. In general, to signal a good neighborhood, worms attach a structure called an indole group to the ascarosides. To signal a bad neighborhood, worms make the side chain very short. But how does a worm control which ascarosides it makes? Zhou, Wang et al. now show that C. elegans can change the meaning of its chemical message by modifying the ascarosides that it has already produced instead of making new ones from scratch. Specifically, as their neighborhood runs out of food, C. elegans can use an enzyme called ACS-7 to initiate the shortening of the side chains of indole-ascarosides. The worm can thus change a favorable ascaroside signal that causes the worms to group together into an unfavorable ascaroside signal that causes the worms to enter their dispersal stage. Although Zhou, Wang et al. have focused on chemical communication in C. elegans, the findings could easily apply to the many other species of roundworm that produce ascarosides. Knowing how worms communicate will help us to understand how worms respond to their environment. This knowledge could potentially be used to interfere with the lifecycles and survival of parasitic worm species that harm health and crops.

We studied newly developed assistive robot movement (ARM, HEXAR-KR40P) equipment, and compared with conventional continuous passive movement (CPM) equipment, focusing on range of motion (ROM) and strengthening of knee joint muscles. 110 osteoarthritis (OA) patients were recruited from five different clinics. At first, eighty patients were enrolled to evaluate the subjective satisfaction of ARM. Secondly, thirty patients were enrolled to find the effectiveness of ARM including ROM and strength compared with CPM. Subjects in first study performed exercise for two weeks. Exercise was performed with CPM and ARM for ten minutes alternately. Subjects in second study performed exercise with ARM only 30 min/day for two weeks, and measured ROM, strength, and functional changes. Obtained data was analyzed with Wilcoxon signed rank test. As a result, higher subjective satisfaction with ARM in patients and researchers survey was noted compared with CPM (p

Prior to developing the wearable walking assistant robot that supports walking for hemiplegia patients, a neural oscillator, a type of CPG (central pattern generation), was applied to 2-DOF double pendulum, which can replace the leg of a robot. The walking pattern generation method was proposed using the gait pattern of the non-affected side of hemiplegia patients. Because it is difficult for hemiplegia patients to distinguish the intended action signal of the patient wearing a robot on their affected side, we had to utilize a limited amount of information to get the maximum effect. We needed an effective solution for robot control in an outside environment where many unknown disturbances exist. In order to deal with these two problems, we used a nonlinear oscillator with a double pendulum as a test bed to explore the possibility of producing a robot walking pattern.

In this paper, we propose a human–robot cooperation controller for the motion of the upper limb exoskeleton. The system permits three degrees of freedom using an electrical actuator that is mainly controlled by force sensor signals. These signals are used to generate the torque required to drive the exoskeleton. However, singularities exist when the force signals in the Cartesian coordinate system are transformed into torques in the joint coordinate system. Therefore, we apply the damped least squares method. When handling a load, torque compensation is required about its mass. Therefore, we installed a force sensor at the point of the robot’s end-effector. It measures the forces between the exoskeleton and the load. Then, these forces are used to compensate within a static model for handling loads. We performed control stability and load handling experiments to verify the effectiveness of the controller. Via these, we confirmed the effectiveness of the proposed controller.

There has been much recent research interest in developing numerous kinds of human-machine interface. This field currently requires more accurate and reliable sensing systems to detect the intended human motion. Most conventional human-machine interface use electromyography (EMG) sensors to detect the intended motion. However, EMG sensors have a number of disadvantages and, as a consequence, the human-machine interface is difficult to use. This study describes a muscle volume sensor (MVS) that has been developed to measure variation in the outline of a muscle, for use as a human-machine interface. We developed an algorithm to calibrate the system, and the feasibility of using MVS for detecting muscular activity was demonstrated experimentally. We evaluated the performance of the MVS via isotonic contraction using the KIN-COM ® equipment at torques of 5, 10, and 15 Nm.

This study uses a muscle activation sensor and elbow joint model to develop an estimation algorithm for human elbow joint torque for use in a human-robot interface. A modular-type MVS (Muscle Volume Sensor) and calibration algorithm are developed to measure the muscle activation signal, which is represented through the normalization of the calibrated signal of the MVS. A Hill-type model is applied to the muscle activation signal and the kinematic model of the muscle can be used to estimate the joint torques. Experiments were performed to evaluate the performance of the proposed algorithm by isotonic contraction motion using the KIN-COM® equipment at 5, 10, and 15Nm. The algorithm and its feasibility for use as a human-robot interface are verified by comparing the joint load condition and the torque estimated by the algorithm.

This study aimed to develop a robot for effective knee joint rehabilitation. A kinematic approach was used to make exoskeleton robot joints to have the same range of motion (ROM) as that of human knee joints, and a robot exoskeleton was proposed to enable the wearer maintain a proper posture during rehabilitation therapy. This robot is generally used for the rehabilitation therapy for knee lesion patients (e.g., after knee replacement arthroplasty and cruciate ligament reconstruction), where the patients usually lie down wearing this robot. The alignment of the knees and body is a critical factor for the success of the therapy. Considering the rehabilitation therapy posture, the robot was manufactured with a kinematic structure different from that of the existing robots for knee rehabilitation therapy. In this study, the kinematic mechanism of the knee rehabilitation robot was described, and the actuator for the robot was selected by measuring the human knee joint motion and torque. Thus, an exoskeleton robot that is significantly different from the existing knee rehabilitation robots was developed.

The exoskeleton robot system is a brand new type of human-robot cooperation system. It fully combines human intelligence and robot power so that robot intelligence and human operator’s power are both enhanced. Therefore, it achieves a high-level performance that neither robots nor humans could achieve separately. This paper describes the basic exoskeleton concepts from biological systems to human-robot intelligent systems. It is followed by an overview of the development history of exoskeleton systems and their two main applications: human power assistance and human power augmentation. Besides the key technologies in exoskeleton systems, the research is presented from several viewpoints of the biomechanical design, system structure modeling, human-robot interaction, and control strategy.

Latest, many researchers do research on wearable robot. The purpose of the researches is very diverse, it will improve efficiency in the industry, taken to replace the many workers in the military field and taken to assist bodily functions run out by aging. However, there is no clear Differentiated strategy depending on the purpose for design and control of the wearable robot. Although a common purpose is to drive the robot by the sensor signal (intent signals), the optimization about the mechanism and control studies must be done according to the user`s physical ability and purpose. In this study, the study`s first phase for the development of wearable robotic gait rehabilitation, gait characteristics were analyzed elders and hemiplegia patients using a 3D gait analysis system (VICON512). As a result, asymmetric gait characteristics of the hemiplegia patients were found compared with the normal elderly.

This paper proposes a human-robot cooperative control of exoskeleton robot assisting muscle strength of a human upper extremity when lifting or transporting heavy objects. When a human wears a robot, the motions of the human and robot generate interaction, which is called HRI (Human-Robot Interaction). To generate reference motion from the interaction force, a pHRI model was developed using virtual mechanical impedance, and an experimental method to determine the impedance parameters of the pHRI model was proposed. The controller was developed in such a way that the desired motion will be controlled using dynamic model-based compensation. To verify the proposed control method, it was applied to an exoskeleton robot with 6-DOF for both arms. Motion-following-performance experiment and muscle-strength-assisting-effect experiment were conducted using this robot. Experimental results, the wearer of the exoskeleton robot can handle a small force was the heavy object.

In this study, a muscle volume sensor was developed to estimate the human behavior for its application to bioengineering and synchronous signal collection. The sensor is easily manufactured at a low cost. In addition, its wearability is good, and it can measure the human motion intent using a simple algorithm. This study tested the developed sensor, verified the test results, and applied the sensor to an actual wearable robot to further verify its effectiveness. The results of this study can allow the application of the sensor for a gait assistance device, to the upper and lower extremities, and to medical and industrial equipment.

The purpose of this study is to verify the energy efficiency of the integrated system combining human and a lower extremity exoskeleton robot when it is applied to the proposed gait pattern. Energy efficient gait pattern of the lower limb was proposed through leg function distribution during stance phase and the dynamic-manipulability ellipsoid (DME). To verify the feasibility and effect of the redefined gait trajectory, simulations and experiments were conducted under the conditions of walking on level ground and ascending and descending from a staircase. Experiments to calculate the metabolic cost of the human body with or without the assistance of the exoskeleton were conducted. The energy consumption of the lower extremity exoskeleton was assessed, with the aim of improving the efficiency of the integrated system.

This study proposes a lower-limb exoskeleton system that is controlled by a wearer's muscle activity. This system is designed by following procedure. First, analyze the muscle activation patterns of human leg while walking. Second, select the adequate actuator to support the human walking based on calculation of required force of knee joint for step walking. Third, unit type knee and ankle orthotics are integrated with selected actuator. Finally, using this knee-assistive system (KAS) and developed muscle stiffness sensors (MSS), the muscle activity pattern of the subject is analyzed while he is walking on the stair. This study proposes an operating algorithm of KAS based on command signal of MSS which is generated by motion intent of human. A healthy and normal subject walked while wearing the developed powered-knee exoskeleton on his/her knees, and measured effectively assisted plantar flexor strength of the subject's knees and those neighboring muscles. Finally, capabilities and feasibility of the KAS are evaluated by testing the adapted motor pattern and the EMG signal variance while walking with exoskeleton. These results shows that developed exoskeleton which controlled by muscle activity could help human's walking acceptably.

Patients with paralyzed upper extremities due to central nervous system lesion after stroke, traumatic brain injury and spinal cord injury receive rehabilitation therapy. The rehabilitation robot is studied for the effective therapy. To train the patients more effectively, it is necessary to study not only mechanisms of robots but also control strategy for rehabilitation. The purpose of various control algorithms for therapy is to implement various training repetitively and intensively. Then, these control strategies can induce the plasticity of motors and brain and improve patient's motor recovery. In this paper, we propose the upper limb robot system for neurorehabilitation. This robot is combined with the path control algorithm applying H-infinity optimization to impedance control for virtual tunnel. We present the entire robot system, robot's mechanism and procedure of optimizing the path controller for robustness. Also, the robot system is verified by test with a healthy person before it applies to the paralyzed patients.

Need to develop human body's posture supervised robots, gave the push to researchers to think over dexterous design of exoskeleton robots. It requires to develop quantitative techniques to assess motor function and generate the command for the robots to act accordingly with complex human structure. In this paper, we present a new technique for the upper limb power exoskeleton robot in which load is gripped by the human subject and not by the robot while the robot assists. Main challenge is to find non-biological signal based human desired motion intention to assist as needed. For this purpose, we used newly developed Muscle Circumference Sensor (MCS) instead of electromyogram (EMG) sensors. MCS together with the force sensors is used to estimate the human interactive force from which desired human motion is extracted using adaptive Radial Basis Function Neural Network (RBFNN). Developed Upper limb power exoskeleton has seven degrees of freedom (DOF) in which five DOF are passive while two are active. Active joints include shoulder and elbow in Sagittal plane while abduction and adduction motion in shoulder joint is provided by the passive joints. To ensure high quality performance model reference based adaptive impedance controller is employed. Exoskeleton performance is evaluated experimentally by a neurologically intact subject which validates the effectiveness.

he purpose of this study is to measure bio-signal to investigate the driver`s physiological response change under real situation using train simulator. The train simulator used in this study is KTX model and according to changes of driving situation, The bio-signal controlled by autonomic nervous system, such as GSR(Galvanic Skin Response), SpO2(Saturation percent O2), HR(Heart Rate), ECG(Electrocardiograph), EEG(Electroencephagram) and movement and response of eye were measured. Statistically significant difference in bio-signal data and eye movement activity pattern were investigated under several different driving speeds using analysis of variance (p

The purpose of this study is to define how wrist motion is affected by different postures and supporting devices and to discover functional range of wrist motion for keyboard typing. The range of wrist motion (ROM) needed for fourteen experienced typists to type on a computer keyboard was measured by flexible and biaxial electrogoniometers. The most frequent wrist motion during typing was in extended and ulnarly deviated positions in both wrists. Range of wrist motion was similar in both wrists. The average ROM for keyboard typing with the typists’ own posture was about 39° in flexion/extension (FEM) and 29° in radial/ulnar deviation (RUD) in both wrists. The range of wrist motion was significantly reduced to 30° in FEM and 27° in RUD with use of either wrist or forearm supporting devices, which suggests that these devices might help to relieve fatigue, discomfort, or pain during and/or after typing. Results of this study will be of interest to clinicians and helpful to those who are professionally or nonprofessionally involved in typing.

This study developed a lower extremity exoskeleton system to enhance lower body strength. In this paper, selected the degrees of freedom (DOF) which actuated based on analyzed human motion, and analyzed the human joint function to design the joint modules of the exoskeletal robot. To improve the efficiency of the exoskeleton robot, a mechanical structure was designed on the basis of a semi-anthropomorphic architecture. The Hanyang EXskeleton Assistive Robot (HEXAR) has seven degrees of freedom per leg, two of which are powered by an electrical motor. Appropriately sized motors and gearing are selected, and put through a thorough power analysis. quasi-passive mechanisms were designed with compliance material for supporting the weight of external loads in the stance phase and absorbing/releasing the energy. This paper discusses design criteria considered in mechanical design for HEXAR.

Need to develop human body's posture supervised robots, gave the push to researchers to think over dexterous design of exoskeleton robots. It requires to develop quantitative techniques to assess motor function and generate the command for the robots to act accordingly with complex human structure. In this paper, we focus on developing new technique for the upper limb power exoskeleton in which load is handled by the human subject and not by the robot. Main challenge along with the design complexity is to find the desired human motion intention and to develop an algorithm to assist as needed accordingly. For this purpose, we used newly developed Muscle Circumference Sensor (MCS) instead of electromyogram (EMG) sensors. MCS together with the load cells is used to estimate the desired human intention by which desired trajectory is generated. The desired trajectory is then tracked by passivity based adaptive control technique. Developed Upper limb power exoskeleton has seven degrees of freedom (DOF) in which five are passive and two are active. Active joints include shoulder and elbow, powered by electric motors and move in Sagittal plane while abduction and adduction motion in shoulder joint is provided by the passive joint. Performance of the exoskeleton is evaluated experimentally by a neurologically intact subject. The results show that after adjusting the motion intention recognition algorithm for the subject, the robot assisted effectively and the subject only felt nominal load regardless of the weight in hand.

A biomechanical study was conducted in this study to investigate if in-line skating wrist guards can effectively reduce the impact forces so as to protect the wrist from fracture. The forearm specimens with and without wrist guards were dropped using a specially designed sled to simulate the impact on the wrist while falling. A force plate was used to measure the total impact force on the dropping weight whereas a load cell was attached to the proximal end of the specimen and used to quantify the impact transmitted through the wrist joint. From the nondestructive tests, mean peak force measured from a force plate showed no difference between the guarded and unguarded groups whereas mean impulse of the guarded group was significantly greater than that of the unguarded group (p

A series of rabbit common extensor tendon specimens of the humeral epicondyle were subjected to tensile tests under two displacement rates (100 mm/min and 10 mm/min) and different elbow flexion positions 45°, 90° and 135°. Biomechanical properties of ultimate tensile strength, failure strain, energy absorption and stiffness of the bone-tendon specimen were determined. Statistically significant differences were found in ultimate tensile strength, failure strain, energy absorption and stiffness of bone-tendon specimens as a consequence of different elbow flexion angles and displacement rates. The results indicated that the bone-tendon specimens at the 45° elbow flexion had the lowest ultimate tensile strength; this flexion angle also had the highest failure strain and the lowest stiffness compared to other elbow flexion positions. In comparing the data from two displacement rates, bone-tendon specimens had lower ultimate tensile strength at all flexion angles when tested at the 10 mm/min displacement rate. These results indicate that creep damage occurred during the slow displacement rate. The major failure mode of bone-tendon specimens during tensile testing changed from 100% of midsubstance failure at the 90° and 135° elbow flexion to 40% of bone-tendon origin failure at 45°. We conclude that failure mechanics of the bone-tendon unit of the lateral epicondyle are substantially affected by loading direction and displacement rate.

The purpose of this study was to investigate the effect of cyclic loading, which produced the condition of ACLs during sports activities, on tensile properties of femur-ACL-tibia complexes (FATCs). Paired FATCs of 40 New Zealand white rabbits were tested on a materials testing machine. One specimen of each pair was designated as a control and loaded until failure. The contralateral specimen was loaded cyclically (1.4 Hz, 1 hr.) with 20%, 30%, 40%, or 50% of ultimate tensile strength (UTS) of the control and then loaded until failure. The UTS and mode of failure were recorded after each test. Five specimens ruptured during cyclic loading in the 50% group. In the 40% group, the mean value of UTS of cycled specimens was significantly lower than that of controls. There was no statistically significant difference in UTS values between control and cycled specimens in the 20% and 30% groups. Cycled specimens had a significantly higher incidence of substance failure than controls. Our results demonstrated that FATCs have the strength to withstand cyclic loading within normal sports activity levels. However, FACTs can be damaged by cyclic loading under strenuous sports activity levels. We speculate that cyclic loading makes the ACL substance weaker than the insertion site.

Interferon (INF) is an effective drug in treating several human diseases. Ge-132, which is the most common and well-studied organic germanium, has been reported to induce INF-gamma and has undergone clinical trials with promising preclinical results. However, it has been reported that long-term ingestion or high doses of organic Ge-132 causes similar toxic effects as GeO(2) because Ge-132 can be easily contaminated with significant amounts of inorganic germanium during the preparation. In this study, we synthesized the water-soluble organogermanium compound (Ge-OH) without possible contamination with toxic inorganic germanium and showed that Ge-OH is a better INF-gamma inducer than Ge-132 by an animal study.

The effects of isomeric oxydiphenylene diamines (ODA), 3,4'ODA and 4,4'ODA, on the water sorption behavior in pyromellitic dianhydride (PMDA)-ODA, biphenyltetracarboxylic dianhydride (BPDA)-ODA, 3,3',4,4'-benzo phenonetetracarboxylic dianhydride (BTDA)-ODA, and 4,4'-hexafluoroisopropylidenediphthalic anhydride (6FDA)-ODA polyimides were gravimetrically investigated. Water sorption curves were reasonably well fitted by Fickian diffusion despite their morphological heterogeneities in the polyimide thin films. However, the effects of isomeric ODA on the water sorption were quite different depending upon the sort of polyimide. The mutual diffusion coefficient of water and 4,4'ODA based polyimide films varies in the range of 3.0 x 10 -10 cm 2 s to 15.2 x 10 10 cm 2 s -1 . and is in the increasing order: BPDA-4,4'ODA < BTDA-4,4'ODA-PMDA-4,4'ODA < 6FDA-4,4'ODA. The water uptake varies from 1.62wt% to 3.25 wt%, and is in the increasing order: BPDA-4,4'ODA < 6FDA-4,4'ODA < PMDA-4,4'ODA < BTDA-4,4'ODA. However, the diffusion coefficient for 3.4'ODA based polyimide films varies in the range of 6.7 × 10 -10 cm 2 s - to 8.6 × 10 -10 cm 2 s - 1 , and is in the increasing order: BPDA-3,4'ODA < 6FDA-3,4'ODA-BTDA-3,4'ODA-PMDA-3,4'ODA. The water uptake varies from 2.02wt% to 2.98wt%. and is in the increasing order: 6FDA-3,4'ODA < BPDA-3,4'ODA < BTDA-3,4'ODA < PMDA-3,4'ODA. Polyimides having higher chain order, highly crystalline structure, and smaller mean intermolecular distance revealed relativcly lower diffusion coefficients and water uptakes in equilibrium.

Many mathematical techniques have been developed to determine the geometry of articular joint surfaces, because of its so importance to the study of human joint biomechanics. However, a three-dimensional geometric model of the articular joint, which is essential to solid modelling, contact area measurement, and load bearing analyses, has not been well developed. This study proposes to define the articular geometry of the distal femoral joint of the human knee. A mathematical method based on the influence surface theory of plates is established to generate representations of three-dimensional articular surfaces. A mathematical cone and the surface of the human distal femur are accurately recreated, allowing their geometric properties to be determined. Results suggest that this method can be an effective tool for representing articular surfaces.