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Socket-shield technique expands the indications for immediate implant placement and effectively maintains the contour of the labial bone. However, due to its relatively high incidence of complications, the technique has not become routine. Understanding the biomechanical characteristics among different structures in socket-shield technique has clinical significance. In this study, finite element analysis was conducted to investigate the biomechanical correlations with the exposure, migration and fracture of the root shield. Seven three-dimensional finite element models were constructed with jumping gaps of 0mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm and 3mm, respectively. The results illustrate deep overbite loading induces unfavorable biomechanical reactions in various structures in socket-shield technique. For normal occlusion, the jumping gap that is too small leads to stress exceeding the yield strength of the root shield and comparatively large displacement in the root shield, possibly causing fracture and migration of the root shield. The jumping gap that is too large causes micro-damages to the cortical bone around the implant, potentially leading to cortical bone resorption and exposure of the root shield. Therefore, the technique should be avoided in patients with deep overbite loading, and the jumping gap of 1.5–2mm may be a suitable choice.

In this paper, combined with physiological anatomy knowledge, the complete finite element model of L3–L4 lumbosacral segment of human lumbar was established by using the 3D graphic of human spine L3–L4 segment, which is obtained by image diagnosis technique (CT scan). This model includes the sections of the bones, the intervertebral disc and the anterior ligament, the posterior ligament, the ligamentum flavum, the fibrous ring and other major spine attached soft tissue. Then the finite element model meshing and the material properties of the corresponding part setting were done on the constructed model, and different loads and boundary conditions were imposed to simulate the displacement and stress and strain nephogram of the normal model and intervertebral disc herniation, senile degeneration and other models in different movement states. And the effectiveness of model data is verified by analyzing its biomechanical properties. The biomechanical properties of the spine obtained by the finite element method can be used to provide biomechanical basis for the diagnosis and treatment of intervertebral disc herniation and degeneration.

Technological advances in robotic hardware and software have enabled powered exoskeletons to move from science fiction to the real world. The objective of this article is to emphasize two main points for future research. First, the design of future devices could be improved by exploiting biomechanical principles of animal locomotion. Two goals in exoskeleton research could particularly benefit from additional physiological perspective: (i) reduction in the metabolic energy expenditure of the user while wearing the device, and (ii) minimization of the power requirements for actuating the exoskeleton. Second, a reciprocal potential exists for robotic exoskeletons to advance our understanding of human locomotor physiology. Experimental data from humans walking and running with robotic exoskeletons could provide important insight into the metabolic cost of locomotion that is impossible to gain with other methods. Given the mutual benefits of collaboration, it is imperative that engineers and physiologists work together in future studies on robotic exoskeletons for human locomotion.

Biomechanics research shows that the ability of the human locomotor system depends on the functionality of a highly compliant motor system that enables a variety of different motions (such as walking and running) and control paradigms (such as flexible combination of feedforward and feedback controls strategies) and reliance on stabilizing properties of compliant gaits. As a new approach of transferring this knowledge into a humanoid robot, the design and implementation of the first of a planned series of biologically inspired, compliant, and musculoskeletal robots is presented in this paper. Its three-segmented legs are actuated by compliant mono- and biarticular structures, which mimic the main nine human leg muscle groups, by applying series elastic actuation consisting of cables and springs in combination with electrical actuators. By means of this platform, we aim to transfer versatile human locomotion abilities, namely running and later on walking, into one humanoid robot design. First experimental results for passive rebound, as well as push-off with active knee and ankle joints, and synchronous and alternate hopping are described and discussed. BioBiped1 will serve for further evaluation of the validity of biomechanical concepts for humanoid locomotion.

The aim of this paper is trying to propose an efficient method of inverse kinematics and motion generation for redundant humanoid robot arm based on the intrinsic principles of human arm motion. The intrinsic principle analysis takes into account both the skeletal kinematics and muscle strength properties. Firstly, this work analyzed the kinematic redundancy problem of a human arm. By analyzing the biological feature of a human arm, the kinematic redundancy boils down to the uncertainty of elbow position. Secondly, because the muscle’s kinematic and strength properties are critical for simulating biometric motion authentically, the muscle strength property was introduced as the criterion for configuration identification and motion generation. Three types of limb configuration, dog walking, gecko climbing, and human walking limb configuration were analyzed, and two geometrical configuration identification rules were deduced to generate biomimetic motion for humanoid robotic arms. By comparing the proposed method with other five IK methods, the proposed method significantly deduced the computing time. Finally, the configuration identification rules were used to generate motions for a 7-DoF humanoid robotic arm. The results showed that the biological rules can generate biomimetic, smooth arm motions for a redundant humanoid robotic arm.

In sickle cell disease (SCD), hemoglobin molecules polymerize intracellularly and lead to a cascade of events resulting in decreased deformability and increased adhesion of red blood cells (RBCs). Decreased deformability and increased adhesion of sickle RBCs lead to blood vessel occlusion (vaso-occlusion) in SCD patients. Here, we present a microfluidic approach integrated with a cell dimensioning algorithm to analyze dynamic deformability of adhered RBC at the single-cell level in controlled microphysiological flow. We measured and compared dynamic deformability and adhesion of healthy hemoglobin A (HbA) and homozygous sickle hemoglobin (HbS) containing RBCs in blood samples obtained from 24 subjects. We introduce a new parameter to assess deformability of RBCs: the dynamic deformability index (DDI), which is defined as the time-dependent change of the cell's aspect ratio in response to fluid flow shear stress. Our results show that DDI of HbS-containing RBCs were significantly lower compared to that of HbA-containing RBCs. Moreover, we observed subpopulations of HbS containing RBCs in terms of their dynamic deformability characteristics: deformable and non-deformable RBCs. Then, we tested blood samples from SCD patients and analyzed RBC adhesion and deformability at physiological and above physiological flow shear stresses. We observed significantly greater number of adhered non-deformable sickle RBCs than deformable sickle RBCs at flow shear stresses well above the physiological range, suggesting an interplay between dynamic deformability and increased adhesion of RBCs in vaso-occlusive events.

Bladder control problems affect both men and women and range from an overactive bladder, to urinary incontinence, to bladder obstruction and cancer. These disorders affect more than 200 million people worldwide. Loss of bladder function significantly affects the quality of life, both physically and psychologically, and also has a large impact on the healthcare system, i.e., the incurring costs related to diagnosis, treatment and medical/nursing care. Improvements in diagnostic capabilities and disease management are essential to improve patient care and quality of life and reduce the economic burden associated with bladder disorders. This paper summarizes some of the key contributions to understanding the mechanics of the bladder ranging from work conducted in the 1970s through the present time with a focus on material testing and theoretical modeling. Advancements have been made in these areas and a significant contribution to these changes was related to technological improvements.

Modern gait analysis results in large quantities of correlated data. A current challenge in the field is the development of appropriate data analysis techniques for the representation and interpretation of these data. Knee osteoarthritis is a common debilitating disease of the musculoskeletal system that has been the focus of many gait studies in recent years. Various data analysis techniques have been used to extract pathological information from gait data in these studies. The following review discusses the successes and limitations of many of these analysis techniques in the attempt to understand the biomechanics of knee osteoarthritis.

In this research, we propose an "Athlete Robot" which is compatible with a biomechanical structure of a human. In our work, pneumatic muscle is used for the actuator. We also provide a method to describe the properties of musculoskeletal leg with "Convex Polygon of Forces". In the experiment, we observed sway of the center of gravity similar to a human during bipedal stance. Our results show that the robot which has well-designed leg can land softly from one meter drop by exploiting the anti-gravity muscles and its compliance. In addition, by using preset stiffness of the musculoskeletal leg, we can control the direction of the bouncing predictively. The musculoskeletal robot helps to illuminate design principles of the robot which can move quickly and skillfully in the real world.

This paper presents the construction of individual dynamic models of human lower limbs using kinematics from Clinical Gait Analysis(CGA) data and Body Segment Inertia Parameters(BSIP) from predictive equations. It’s used human lower limbs BSIP from predictive equations and human kinematics from CGA data, to get individual BSIP and kinematic data. The the human dynamic model is built in a dynamic simulation software environment, to create human body dynamic models, and the CGA kinematic data is used as input to study model dynamics and control strategies. This approach would allow the testing and simulation of complex dynamic models without going through the tedious and error prone process of manually calculating equations of motion.

It’s shown the use of the strategy presented to collect the data to be used in the simulation of a teen age boy or girl to be used latter in the simulation of a lower limb exoskeleton.