Technology and Health Care - Volume 25, issue S1

Article Type: Other

Citation: Technology and Health Care, vol. 25, no. S1, pp. i-iv, 2017

Authors: Ciaccio, Edward J. | Liu, Feng

Article Type: Other

DOI: 10.3233/THC-171350

Citation: Technology and Health Care, vol. 25, no. S1, pp. 1-, 2017

Authors: Xiao, Feiyun | Gao, Yongsheng | Wang, Yong | Zhu, Yanhe | Zhao, Jie

Article Type: Research Article

Abstract: BACKGROUND: Many countries, including Japan, Italy, and China are experiencing demographic shifts as their populations age. Some basic activities of daily living (ADLs) are difficult for elderly people to complete independently due to declines in motor function. OBJECTIVE: In this paper, a 6-DOF wearable cable-driven upper limb exoskeleton (CABexo) based on epicyclic gear trains structure is proposed. METHODS: The main structure of the exoskeleton system is composed of three epicyclic gear train sections. This new exoskeleton has a parallel mechanical structure to the traditional serial structure, but is stiffer and has a stronger …carrying capacity. The traditional gear transmission structure is replaced with a cable transmission system, which is quieter, and has higher accuracy and smoother transmission. RESULTS AND CONCLUSIONS: The static workspace of the exoskeleton is large enough to meet the demand of assisting aged and disabled individuals in completing most of their activities of daily living (ADLs). Show more

Keywords: Epicyclic gear train, cable-driven, upper limb exoskeleton, pre-tensioner

DOI: 10.3233/THC-171300

Citation: Technology and Health Care, vol. 25, no. S1, pp. 3-11, 2017

Authors: Li, Baolin | Bi, Jiaqi | Li, Wei | Huang, Sainan | Zhang, Shuangli | Zhao, Jian’gang | Meng, Qinggang | Fei, Jianfeng

Article Type: Research Article

Abstract: OBJECTIVE: Bone histomorphometry and the concentration of the serum osteocalcin expression were observed in disuse osteoporosis (DOP) rats in order to explore the mechanism of pulsed electromagnetic fields in treating DOP. METHODS: Female SD rats, weighing 250 ∼ 280 g, were randomly divided into 4 groups: a control group and three experimental groups. The right hindlimbs of all the rats were immobilized by tibia-tail fixation, except for those in the INT group. The ALN group rats were given an alendronate sodium (1 mg kg - 1 …d - 1 ) treatment, and the rats in the PEMF group received PEMF irradiation. Bone histomorphometry and the concentration of serum osteocalcin expression were detected in 2, 4, 8, and 12 weeks. RESULTS: Four weeks after modeling, as compared with the DOP group, the %Tb-Ar and Tb-N in the ALN group were increased, and the difference was significant (P < 0.05 or P < 0.01). At 8 weeks, as compared with the DOP group, the %Tb-Ar and Tb-N in the ALN group and the PEMF group both increased, and there was a significant difference (P < 0.05 or P < 0.01). At 12 weeks, as compared with the DOP group, the BGP serum concentration of the ALN group was reduced, and there was a statistical difference (P < 0.05). CONCLUSION: Pulse electromagnetic field with drug can prevent disuse osteoporosis by changing the bone microstructure. In the long run, PEMF improves the mechanical performance of biological structures better than alendronate sodium does. PEMF may influence the process of bone remodeling by promoting the level of osteocalcin. Show more

Keywords: Pulse electro magnetic fields, disuse osteoporosis, donatello sodium, metrology static parameters

DOI: 10.3233/THC-171301

Citation: Technology and Health Care, vol. 25, no. S1, pp. 13-20, 2017

Authors: Shen, Xiang | Ji, Song | Xie, Zhongmin | Deng, Yongquan

Article Type: Research Article

Abstract: BACKGROUND: Vascular stenting has been widely used to treat vessel stenosis. However, long-term successes of the procedure are often compromised by late stent thrombosis (ST) and in-stent restenosis (ISR), especially in tapered arteries. OBJECTIVE: The aim of this study was to choose a reasonable expansion strategy for tapered arteries. METHODS: A balloon-expandable coronary stent deployment in a tapered vessel was numerically studied fol-lowing three strategies: (i) selecting the proximal diameter of the tapered vessel as the reference diameter to expand the stent, (ii) selecting the middle diameter of the tapered vessel as the reference diameter to …expand the stent, and (iii) selecting the distal diameter of the tapered vessel as the reference diameter to expand the stent. RESULTS: Computational results showed that the first expansion strategy resulted in the maximum vessel stress and the best stent apposition, while the third strategy resulted in the minimal vessel stress and the worst stent appo-sition. Meanwhile, the second expansion strategy achieved a trade-off between the first and third strategies, leading to acceptable vessel stress and stent apposition. CONCLUSIONS: The second expansion strategy is the most reasonable choice for tapered vessels, and it should be considered when implanting a stent. Show more

Keywords: Expansion strategy, tapered artery, coronary stent, finite element analysis

DOI: 10.3233/THC-171302

Citation: Technology and Health Care, vol. 25, no. S1, pp. 21-28, 2017

Authors: Na, Sung Dae | Lee, Gihyoun | Wei, Qun | Seong, Ki Woong | Cho, Jin Ho | Kim, Myoung Nam

Article Type: Research Article

Abstract: BACKGROUND: Fully implantable hearing devices (FIHDs) can be affected by generated biomechanical noise such as mastication noise. OBJECTIVE: To reduce the mastication noise using a piezo-electric sensor, the mastication noise is measured with the piezo-electric sensor, and noise reduction is practiced by the energy difference. METHODS: For the experiment on mastication noise, a skull model was designed using artificial skull model and a piezo-electric sensor that can measure the vibration signals better than other sensors. A 1 kHz pure-tone sound through a standard speaker was applied to the model while the lower jawbone …of the model was moved in a masticatory fashion. RESULTS: The correlation coefficients and signal-to-noise ratio (SNR) before and after application of the proposed method were compared. It was found that the signal-to-noise ratio and correlation coefficients increased by 4.48 dB and 0.45, respectively. CONCLUSION: The mastication noise is measured by piezo-electric sensor as the mastication noise that occurred during vibration. In addition, the noise was reduced by using the proposed method in conjunction with MATLAB. In order to confirm the performance of the proposed method, the correlation coefficients and signal-to-noise ratio before and after signal processing were calculated. In the future, an implantable microphone for real-time processing will be developed. Show more

Keywords: Implantable hearing devices, mastication noise, piezo-electric sensor

DOI: 10.3233/THC-171303

Citation: Technology and Health Care, vol. 25, no. S1, pp. 29-34, 2017

Authors: Yang, Tao | Ding, Li | Zhang, Haibo | Xue, Lihao | Zhang, Wei | Chen, Lianyun | Xiao, Huajun | Qiao, Huiting

Article Type: Research Article

Abstract: BACKGROUND: During high-altitude flight, the protection of the pilot is vital. A partial pressure suit may affect human physiology, especially circulatory physiology. OBJECTIVE: The purpose of this study was to investigate how a partial pressure suit works. METHOD: Ten subjects took part in the flight simulation experiments. Counter pressure at the chest, abdomen, thigh and shank were detected, together with physiological parameters such as heart rate (HR), mean arterial pressure (MAP), stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR). A numerical model was also established to simulate hemo-physiological effects of …the partial pressure suit. RESULTS: The experiment’s results show the non-uniform counter pressure distribution in different parts of the body. There is a linear, proportional relation between TPR and the pressurizing level. HR and MAP increase along with that of the pressure level. SV and CO decrease with the increase of the pressure level. The numerical model simulated the physiological effect of a partial pressure suit. The results were verified by experiment data. The simulation estimated the change of blood flow with the pressure level. CONCLUSIONS: The numerical model provides a potential way to improve the protection of pilots. Show more

Keywords: Partial pressure suit, counter pressure, circulatory physiology, numerical model

DOI: 10.3233/THC-171304

Citation: Technology and Health Care, vol. 25, no. S1, pp. 35-44, 2017

Authors: Wang, Lan | Zhang, Zhenyuan | Yu, Yi | Chen, Guangwei

Article Type: Research Article

Abstract: BACKGROUND: Isokinetic muscle strength training is presently the most advanced method of muscle strength training. However, the existing control schemes of the training equipment are usually limited to the structure of the brake. OBJECTIVE: In order to solve this problem, this paper presents a solution to an isokinetic system based on the force control of a DC servomotor. METHODS: A new fuzzy impedance nonlinear controller is designed by analyzing the relevant requirements of isokinetic motion. A series of force tracking comparison experiments between a fuzzy PI controller and a classical PI controller are …studied. In addition, some strength training experiments employing different driving forces and target speeds are also conducted. RESULTS: The results demonstrate the effectiveness of this fuzzy impedance force tracking control strategy. CONCLUSION: Using the aforementioned methods, a comprehensive motion algorithm was designed. Show more

Keywords: Isokinetic muscle strength training, impedance control, fuzzy control, rehabilitation training

DOI: 10.3233/THC-171305

Citation: Technology and Health Care, vol. 25, no. S1, pp. 45-52, 2017

Authors: Sun, Lei | Wu, Xifeng | Li, Yang | Lin, Zhenyan | Xu, Duoling | Lin, Xuan | Gao, Yongbo

Article Type: Research Article

Abstract: BACKGROUND: The maxillary central incisor is one of the most important anatomical indicators in esthetics, and stress distribution may vary among its five anatomical views (labial, palatal, mesial, distal, and incisal). OBJECTIVE: To compare stress distribution among the five anatomical views of the maxillary central incisor under loading force at five angles and to observe and analyze the stress distribution in the dentin and periodontal ligament. METHODS: We established three-dimensional finite element models of the five different views, which simulated the bite force with a static load force at 0 ∘ , …30 ∘ , 45 ∘ , 60 ∘ , and 90 ∘ . The stress and displacement values for the cementoenamel junction (CEJ)-apical labial, palatal, mesial, and distal and the equivalent stress values on the periodontal ligament of the maxillary central incisor were calculated. RESULTS: As the angle increased, the equivalent stress on the periodontal ligament, overall tooth displacement, equivalent stress, and displacement over the four views increased. The peaks of equivalent stress over the four views appeared within 0.8–17 mm below the CEJ, although all equivalent stress values decreased while approaching the peak. Within 1–19 mm below the CEJ, the equivalent stress over the M1 and P1 views of the maxillary central incisor decreased substantially. CONCLUSION: The peaks of the equivalent stress over the M1 and P1 views of the maxillary central incisor and their stress distribution were lower than those of the other three types. Our findings provided theoretical data on the biomechanics of this esthetically important tooth, which may be useful during implantation of missing maxillary central incisors. Show more

Keywords: Maxillary central incisor, stress, displacement, three-dimensional finite element

DOI: 10.3233/THC-171306

Citation: Technology and Health Care, vol. 25, no. S1, pp. 53-62, 2017

Authors: Kim, Hyoung-Ho | Choi, Young Ho | Lee, Seung Bae | Baba, Yasutaka | Kim, Kyung-Wuk | Suh, Sang-Ho

Article Type: Research Article

Abstract: Ureteral stenosis presents with a narrowing in the ureter, due to an intrinsic or extrinsic ureteral disease, such as ureter cancer or retroperitoneal fibrosis. The placement of a double J stent in the upper urinary system is one of the most common treatments of ureteral stenosis, along with the insertion of a percutaneous nephrostomy tube into the renal pelvis. The effect that the side holes in a double J stent have on urine flow has been evaluated in a few studies using straight ureter models. In this study, urine flow through a double J stent’s side holes was analyzed in …curved ureter models, which were based on human anatomy. In ureteral stenosis, especially in severe ureteral stenosis, a stent with side holes had a positive effect on the luminal and total flow rates, compared with the rates for a stent without side holes. The more side holes a stent has, the greater the luminal and total flow rates. However, the angular positions of the side holes did not affect flow rate. In conclusion, the side holes in a double J stent had a positive effect on ureteral stenosis, and the effect became greater as the ureteral stenosis became more severe. Show more

Keywords: Ureter, stent, urine flow, CFD, numerical analysis

DOI: 10.3233/THC-171307

Citation: Technology and Health Care, vol. 25, no. S1, pp. 63-72, 2017