Bionic optic nerve based on perovskite (CsPbBr 3) quantum-dots / 生物医学工程学杂志

The bionic optic nerve can mimic human visual physiology and is a future treatment for visual disorders. Photosynaptic devices could respond to light stimuli and mimic normal optic nerve function. By modifying (Poly(3,4-ethylenedioxythio-phene):poly (styrenesulfonate)) active layers with all-inorganic perovskite quantum dots, with an aqueous solution as the dielectric layer in this paper, we developed a photosynaptic device based on an organic electrochemical transistor (OECT). The optical switching response time of OECT was 3.7 s. To improve the optical response of the device, a 365 nm, 300 mW·cm -2 UV light source was used. Basic synaptic behaviors such as postsynaptic currents (0.225 mA) at a light pulse duration of 4 s and double pulse facilitation at a light pulse duration of 1 s and pulse interval of 1 s were simulated. By changing the way light stimulates, for example, by adjusting the intensity of the light pulses from 180 to 540 mW·cm -2, the duration from 1 to 20 s, and the number of light pulses from 1 to 20, the postsynaptic currents were increased by 0.350 mA, 0.420 mA, and 0.466 mA, respectively. As such, we realized the effective shift from short-term synaptic plasticity (100 s recovery of initial value) to long-term synaptic plasticity (84.3% of 250 s decay maximum). This optical synapse has a high potential for simulating the human optic nerve.

Effectiveness of proximal femur bionic nail for intertrochanteric fracture in the elderly / 中国修复重建外科杂志

OBJECTIVE@#To evaluate effectiveness of proximal femur bionic nail (PFBN) in treatment of intertrochanteric fractures in the elderly compared to the proximal femoral nail antirotation (PFNA).@*METHODS@#A retrospective analysis was made on 48 geriatric patients with intertrochanteric fractures, who met the selection criteria and were admitted between January 2020 and December 2022. Among them, 24 cases were treated with PFBN fixation after fracture reduction (PFBN group), and 24 cases were treated with PFNA fixation (PFNA group). There was no significant difference in baseline data such as age, gender, cause of injury, side and type of fracture, time from injury to operation, and preoperative mobility score, American Society of Anesthesiologists (ASA) score, Alzheimer's disease degree scoring, self-care ability score, osteoporosis degree (T value), and combined medical diseases between the two groups ( P>0.05). The operation time, intraoperative blood loss, number of blood transfusions, transfusion volume, length of hospital stay, occurrence of complications, weight-bearing time after operation, and postoperative visual analogue scale (VAS) score, walking ability score, mobility score, self-care ability score were recorded and compared between the two groups. And the radiographic assessment of fracture reduction quality and postoperative stability, and fracture healing time were recorded.@*RESULTS@#The operations in both groups were successfully completed. All patients were followed up 6-15 months with an average time of 9.8 months in PFBN group and 9.6 months in PFNA group. The operation time was significantly longer in PFBN group than in PFNA group ( P<0.05), but there was no significant difference in intraoperative blood loss, number of blood transfusions, transfusion volume, length of hospital stay, change in activity ability score, and change in self-care ability score between the two groups ( P>0.05). The weight-bearing time after operation was significantly shorter in PFBN group than in PFNA group ( P<0.05), and the postoperative VAS score and walking ability score were significantly better in PFBN group than in PFNA group ( P<0.05). Radiographic assessment showed no significant difference in fracture reduction scores and postoperative stability scores between the two groups ( P>0.05). All fractures healed and there was no significant difference in fracture healing time between the two groups ( P>0.05). The incidence of complications was significantly lower in PFBN group (16.7%, 4/24) than in PFNA group (45.8%, 11/24) ( P<0.05).@*CONCLUSION@#Compared with PFNA, PFBN in the treatment of elderly intertrochanteric fractures can effectively relieve postoperative pain, shorten bed time, reduce the risk of complications, and facilitate the recovery of patients' hip joint function and walking ability.

Influence of bionic texture coronary stent on hemodynamics after implantation / 生物医学工程学杂志

To explore the influence of bionic texture coronary stents on hemodynamics, a type of bioabsorbable polylactic acid coronary stents was designed, for which a finite element analysis method was used to carry out simulation analysis on blood flow field after the implantation of bionic texture stents with three different shapes (rectangle, triangle and trapezoid), thus revealing the influence of groove shape and size on hemodynamics, and identifying the optimal solution of bionic texture groove. The results showed that the influence of bionic texture grooves of different shapes and sizes on the lower wall shear stress region had a certain regularity. Specifically, the improvement effect of grooves above 0.06 mm on blood flow characteristics was poor, and the effect of grooves below 0.06 mm was good. Furthermore, the smaller the size is, the better the improvement effect is, and the 0.02 mm triangular groove had the best improvement effect. Based on the results of this study, it is expected that bionic texture stents have provided a new method for reducing in-stent restenosis.

Independent innovation research, development and transformation of precise bionic repair technology for oral prosthesis / 北京大学学报(医学版)

According to the fourth national oral health epidemiological survey report (2018), billions of teeth are lost or missing in China, inducing chewing dysfunction, which is necessary to build physiological function using restorations. Digital technology improves the efficiency and accuracy of oral restoration, with the application of three-dimensional scans, computer-aided design (CAD), computer-aided manufacturing (CAM), bionic material design and so on. However, the basic research and product development of digital technology in China lack international competitiveness, with related products basically relying on imports, including denture 3D design software, 3D oral printers, and digitally processed materials. To overcome these difficulties, from 2001, Yuchun Sun's team, from Peking University School and Hospital of Stomatology, developed a series of studies in artificial intelligence design and precision bionics manufacturing of complex oral prostheses. The research included artificial intelligence design technology for complex oral prostheses, 3D printing systems for oral medicine, biomimetic laminated zirconia materials and innovative application of digital prosthetics in clinical practice. The research from 2001 to 2007 was completed under the guidance of Prof. Peijun Lv and Prof. Yong Wang. Under the support of the National Natural Science Foundation of China, the National Science and Technology Support Program, National High-Tech R & D Program (863 Program) and Beijing Training Project for the Leading Talents in S & T, Yuchun Sun's team published over 200 papers in the relevant field, authorized 49 national invention patents and 1 U.S. invention patent and issued 2 national standards. It also developed 8 kinds of core technology products in digital oral prostheses and 3 kinds of clinical diagnosis and treatment programs, which significantly improved the design efficiency of complex oral prostheses, the fabrication accuracy of metal prostheses and the bionic performance of ceramic materials. Compared with similar international technologies, the program doubled the efficiency of bionic design and manufacturing accuracy and reduced the difficulty of diagnosis and cost of treatment and application by 50%, with the key indicators of those products reaching the international leading level. This program not only helped to realize precision, intelligence and efficiency during prostheses but also provided functional and aesthetic matches for patients after prostheses. The program was rewarded with the First Technical Innovation Prize of the Beijing Science and Technology Awards (2020), Gold Medal of Medical Research Group in the First Medical Science and Technology Innovation Competition of National Health Commission of the People's Republic of China (2020) and Best Creative Award in the First Translational Medical Innovation Competition of Capital (2017). This paper is a review of the current situation of artificial intelligence design and precision bionics manufacturing of complex oral prosthesis.

Application of bionics in spinal surgery / 中华外科杂志

Spinal bionic therapy is the application of bionics concept, by imitating the natural anatomical structure and physiological function of the spine, to treat spinal diseases using various modern technology, materials and equipment .How to repair or preserve the anatomical structure and function of spine to the maximum extent while treating spinal diseases is an important content of spinal bionic therapy.Firstly, the use of movable spinal implants not only preserves the spinal mobility function to a certain extent, reduces the degeneration of adjacent segments, but also reduces the incidence of internal fixation fracture and improves the long-term efficacy.Secondly, with the help of the development of three dimensional printing technology, personalized artificial prostheses can be made to fill the spinal structure with complex defects, and biological scaffolds and functional prostheses with anti-tumor drugs can not only realize the biomimetic and functional spine anatomy, but also become a multiplier of the efficacy of anti-tumor drugs.Thirdly, in the design and manufacture of spinal orthopaedic braces, computer aided design and manufacturing technology can make spinal orthopaedic braces more comfortable with better orthopaedic effect and ergonomic characteristics.How to apply bionics concepts and relate technologies to spinal surgery have not been determined yet, and no relevant diagnosis and treatment guidelines have been formulated.It is foreseeable that with the continuous development of medical technology, the content of spinal bionic therapy will be gradually enriched and improved, and become a powerful measure to overcome difficulties in the diagnosis and treatment of spinal surgery diseases.

The development of artificial cervical disc replacement from the perspective of orthopedic bionic therapy / 中华外科杂志

The modern surgical treatment of cervical degenerative disc disease can be traced back to the advent of anterior cervical decompression and fusion.With the emergence of fusion-related complications,different scholars have promoted the gradual transformation of cervical degenerative disc diseases from "fusion fixation" to "non-fusion reconstruction" through in-depth fusion with materials science,engineering mechanics and other disciplines.The innovation of this treatment concept is consistent with the original intention of "structural remodeling,functional reconstruction,maximum repair and reconstruction of the morphology and function of skeletal muscle system" in orthopedic bionic treatment,which is essentially in line with the "bionic alternative therapy" in orthopedic bionic therapy.This paper focuses on the surgical treatment of cervical degenerative disc diseases,reviews the development history of artificial cervical disc replacement,analyzes the evolution from orthopedic biomimetic therapy,and explores a new direction for the design of artificial cervical disc prostheses and the treatment of cervical degenerative disc diseases in the future.

Biomedical applications of bionic untethered micro-nano robots / 生物医学工程学杂志

Bionic untethered micro-nano robots, due to their advantages of small size, low weight, large thrust-to-weight ratio, strong wireless mobility, high flexibility and high sensitivity, have very important application values in the fields of biomedicine, such as disease diagnosis, minimally invasive surgery, targeted therapy, etc. This review article systematically introduced the manufacturing methods and motion control, and discussed the biomedical applications of bionic untethered micro-nano robots. Finally, the article discussed the possible challenges for bionic untethered micro-nano robots in the future. In summary, this review described bionic untethered micro-nano robots and their potential applications in biomedical fields.

The research progress of bionic scaffolds in ligament tissue engineering / 生物医学工程学杂志

Ligaments are dense fibrous connective tissue that maintains joint stability through bone-to-bone connections. Ligament tears that due to sports injury or tissue aging usually require surgical intervention, and transplanting autologous, allogeneic, or artificial ligaments for reconstruction is the gold standard for treating such diseases in spite of many drawbacks. With the development of materialogy and manufacturing technology, engineered ligament tissue based on bioscaffold is expected to become a new substitute, which can lead to tissue regeneration by simulating the structure, composition, and biomechanical properties of natural tissue. This paper reviewed some recently published

A bionic cerebellar motion control model and its application in arm control / 生物医学工程学杂志

How to realize the control of limb movement and apply it to intelligent robot systems at the level of cerebellar cortical neurons is a hot topic in the fields of artificial intelligence and rehabilitation medicine. At present, the cerebellar model usually used is only for the purpose of controlling the effect, borrowing from the functional mode of the cerebellum, but it ignores the structural characteristics of the cerebellum. In fact, in addition to being used for controlling purposes, the cerebellar model should also have the interpretability of the control process and be able to analyze the consequences of cerebellar lesions. Therefore, it is necessary to establish a bionic cerebellar model which could better express the characteristics of the cerebellum. In this paper, the process that the cerebellum processes external input information and then generates control instructions at the neuron level was explored. By functionally segmenting the cerebellum into homogeneous structures, a novel bionic cerebellar motion control model incorporating all major cell types and connections was established. Simulation experiments and force feedback device control experiments show that the bionic cerebellar motion control model can achieve better control effect than the currently widely used cerebellar model articulation controller, which verifies the effectiveness of the bionic cerebellar motion control model. It has laid the foundation for real brain-like artificial intelligence control.

Bionic mechanical design and 3D printing of novel porous Ti6Al4V implants for biomedical applications / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

In maxillofacial surgery, there is a significant need for the design and fabrication of porous scaffolds with customizable bionic structures and mechanical properties suitable for bone tissue engineering. In this paper, we characterize the porous Ti6Al4V implant, which is one of the most promising and attractive biomedical applications due to the similarity of its modulus to human bones. We describe the mechanical properties of this implant, which we suggest is capable of providing important biological functions for bone tissue regeneration. We characterize a novel bionic design and fabrication process for porous implants. A design concept of "reducing dimensions and designing layer by layer" was used to construct layered slice and rod-connected mesh structure (LSRCMS) implants. Porous LSRCMS implants with different parameters and porosities were fabricated by selective laser melting (SLM). Printed samples were evaluated by microstructure characterization, specific mechanical properties were analyzed by mechanical tests, and finite element analysis was used to digitally calculate the stress characteristics of the LSRCMS under loading forces. Our results show that the samples fabricated by SLM had good structure printing quality with reasonable pore sizes. The porosity, pore size, and strut thickness of manufactured samples ranged from (60.95± 0.27)% to (81.23±0.32)%, (480±28) to (685±31) μm, and (263±28) to (265±28) μm, respectively. The compression results show that the Young's modulus and the yield strength ranged from (2.23±0.03) to (6.36±0.06) GPa and (21.36±0.42) to (122.85±3.85) MPa, respectively. We also show that the Young's modulus and yield strength of the LSRCMS samples can be predicted by the Gibson-Ashby model. Further, we prove the structural stability of our novel design by finite element analysis. Our results illustrate that our novel SLM-fabricated porous Ti6Al4V scaffolds based on an LSRCMS are a promising material for bone implants, and are potentially applicable to the field of bone defect repair.

Study on an Exoskeleton Hand Function Training Device / 生物医学工程学杂志

Based on the structure and motion bionic principle of the normal adult fingers, biological characteristics of human hands were analyzed, and a wearable exoskeleton hand function training device for the rehabilitation of stroke patients or patients with hand trauma was designed. This device includes the exoskeleton mechanical structure and the electromyography (EMG) control system. With adjustable mechanism, the device was capable to fit different finger lengths, and by capturing the EMG of the users' contralateral limb, the motion state of the exoskeleton hand was controlled. Then driven by the device, the user's fingers conducting adduction/abduction rehabilitation training was carried out. Finally, the mechanical properties and training effect of the exoskeleton hand were verified through mechanism simulation and the experiments on the experimental prototype of the wearable exoskeleton hand function training device.

Stress analysis of artificial bionic knee joint based on UG6.0 NX NASTRAN / 生物医学工程学杂志

This article introduces the basic principles of finite element analysis in biomechanics, focusing on the basic principles of a variety of finite element analysis software, and their respective characteristics. In addition, it also de scribes the basic stress analysis of UGNX6.0 NASTRAN analysis for artificial knee process, i. e. the choice of the type, material definition, the set of constants, finite element mesh division and the finite element results of the analysis. Finite element analysis and evaluation of the design of personalized artificial knee were carried out, so that the rationality of the geometric design of the structure of the experimental design of artificial knee has been verified.

Recent progress of research and applications of fractal and its theories in medicine / 生物医学工程学杂志

Fractal, a mathematics concept, is used to describe an image of self-similarity and scale invariance. Some organisms have been discovered with the fractal characteristics, such as cerebral cortex surface, retinal vessel structure, cardiovascular network, and trabecular bone, etc. It has been preliminarily confirmed that the three-dimensional structure of cells cultured in vitro could be significantly enhanced by bionic fractal surface. Moreover, fractal theory in clinical research will help early diagnosis and treatment of diseases, reducing the patient's pain and suffering. The development process of diseases in the human body can be expressed by the fractal theories parameter. It is of considerable significance to retrospectively review the preparation and application of fractal surface and its diagnostic value in medicine. This paper gives an application of fractal and its theories in the medical science, based on the research achievements in our laboratory.

Design and preparation of polyurethane-collagen/heparin-conjugated polycaprolactone double-layer bionic small-diameter vascular graft and its preliminary animal tests / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>People recently realized that it is important for artificial vascular biodegradable graft to bionically mimic the functions of the native vessel. In order to overcome the high risk of thrombosis and keep the patency in the clinical small-diameter vascular graft (SDVG) transplantation, a double-layer bionic scaffold, which can offer anticoagulation and mechanical strength simultaneously, was designed and fabricated via electrospinning technique.</p><p><b>METHODS</b>Heparin-conjugated polycaprolactone (hPCL) and polyurethane (PU)-collagen type I composite was used as the inner and outer layers, respectively. The porosity and the burst pressure of SDVG were evaluated. Its biocompatibility was demonstrated by the 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H tetrazolium bromide (MTT) test in vitro and subcutaneous implants in vivo respectively. The grafts of diameter 2.5 mm and length 4.0 cm were implanted to replace the femoral artery in Beagle dog model. Then, angiography was performed in the Beagle dogs to investigate the patency and aneurysm of grafts at 2, 4, and 8 weeks post-transplantation. After angiography, the patent grafts were explanted for histological analysis.</p><p><b>RESULTS</b>The double-layer bionic SDVG meet the clinical mechanical demand. Its good biocompatibility was proven by cytotoxicity experiment (the cell's relative growth rates (RGR) of PU-collagen outer layer were 102.8%, 109.2% and 103.5%, while the RGR of hPCL inner layer were 99.0%, 100.0% and 98.0%, on days 1, 3, and 5, respectively) and the subdermal implants experiment in the Beagle dog. Arteriography showed that all the implanted SDVGs were patent without any aneurismal dilatation or obvious anastomotic stenosis at the 2nd, 4th, and 8th week after the operation, except one SDVG that failed at the 2nd week. Histological analysis and SEM showed that the inner layer was covered by new endothelial-like cells.</p><p><b>CONCLUSION</b>The double-layer bionic SDVG is a promising candidate as a replacement of native small-diameter vascular graft.</p>

Bionic model for coordinated head-eye motion control / 生物医学工程学杂志

The relationships between eye movements and head movements of the primate during gaze shifts are analyzed in detail in the present paper. Applying the mechanisms of neurophysiology to engineering domain, we have improved the robot eye-head coordination. A bionic control strategy of coordinated head-eye motion was proposed. The processes of gaze shifts are composed of an initial fast phase followed by a slow phase. In the fast phase saccade eye movements and slow head movements were combined, which cooperate to bring gaze from an initial resting position toward the new target rapidly, while in the slow phase the gaze stability and target fixation were ensured by the action of the vestibulo-ocular reflex (VOR) where the eyes and head rotate by equal amplitudes in opposite directions. A bionic gaze control model was given. The simulation results confirmed the effectiveness of the model by comparing with the results of neurophysiology experiments.

The Past, Present and Future of Bionic Devices Restoring Cranial Nerve Function / 대한평형의학회지

No abstract available.

A method based on wavelet package transform for denoising electromyographic signal / 生物医学工程学杂志

The detection and analysis of electromyographic signal is of far reaching importance for clinical diagnosis as well as for convalescence medicine. Electromyographic signal is a kind of biological signal in the background full of noise, so it is somewhat difficult to detect and extract the electromyographic signal. In this paper is discussed how to use the method of wavelet package transform to denoise the electromyographic signal on the basis of its feature and its relationship with noise. The results of simulation and application in the Electromyographic Evoked Potential Measuring System independently developed by our laboratory illuminate that the method is effective for denoising electromyographic signal.

Reflexiones bioéticas acerca de la enseñanza de la medicina en simuladores electrónicos

El surgimiento de los simuladores electrónicos para la enseñanza de la medicina amerita refl exiones desde la bioética relacionadas con el reforzamiento del paradigma biomédico imperante, el mecanicismo cartesiano- newtoniano que considera al cuerpo humano como una máquina, el enfoque biológico monocausal, objetivable y medible de la salud y la enfermedad, entre otros. Por medio de la biotecnología, nuestro cuerpo se ha convertido en un “cyborg” y vivimos en una “cyborgcul tura”. De otra parte, el uso de simuladores con fi nes de adquirir habilidades y destrezas para los estudiantes podría facilitar la adquisición de estos, obviando el realizarlo necesariamente en las personas enfermas, al menos en las fases iniciales de la enseñanza clínica. Se argumenta a favor de los simuladores la escasez de pacientes, cada vez mayor, para lograr la formación del futuro profesional. Además, la práctica en los simuladores permite repetir cuantas veces sea necesario el procedimiento que se expone para el aprendizaje.

Description of Simulium damascenoi (Diptera: Simuliidae) male and the black-fly species from the State of Amapá, Brazil

Five species are included in the Simulium siolii group, which is placed in the subgenus Psaroniocompsa (Diptera: Simuliidae). Of these five species, only two (Simulium siolii Py-Daniel and Simulium tergospinosum Hamada) have been described in all their life stages, except eggs. Knowledge of the taxonomic characters of all life stages of a species is important in order to clarify interspecific and higher-level taxonomic relationships. The objectives of the present study are to describe the male of Simulium damascenoi Py-Daniel, to provide a list of black-fly species their bionomics and distributions in the state of Amapá, Brazil, and to provide an identification key for larvae and pupae for these species