Journal of Biomechanical Science and Engineering最新文献

{"title":"Workspace, dexterity and position planning of a 5DOF single-hole laparoscopic surgery robot","authors":"Heqiang Tian, Jianyong Li, Zheng Chenling, Jiakun Jiang","doi":"10.1299/JBSE.18-00544","DOIUrl":"https://doi.org/10.1299/JBSE.18-00544","url":null,"abstract":"","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.18-00544","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66265494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a coupled human fluid numerical model for the evaluation of tsunami drowning hazards","authors":"Daiki Ajima, Takashi Nakamura, T. Araki, Tetsunori Inoue, Akane Kurisu","doi":"10.1299/JBSE.18-00321","DOIUrl":"https://doi.org/10.1299/JBSE.18-00321","url":null,"abstract":"A numerical simulation model for the evaluation of the effectiveness of lifejackets against drowning in tsunamis considering both unsteady water currents and human movement was developed. The Constrained Interpolation Profile-Combined Unified Procedure scheme was combined with the link segment model to simulate interactions between the fluid and subjects in the developed model. The developed model was experimentally validated using a large flume. A manikin laid on blocks was swept down by a tsunami-like water current and caught by a vortex behind the blocks. The developed model accurately reproduced both water currents and the movement of the manikin and was thus considered adequate to analyze the movement of human bodies in tsunamis. The model was then used to analyze the movement of a human body in the same currents but with higher buoyancy, assumed to represent a lifejacket. Consequently, buoyancy greater than a human’s body weight was required to keep the subject afloat; a buoyancy corresponding to the body weight caused the total submergence of the entire subject. Through comparison of forces applied to the body with its movement, it is revealed that a human body receives strong downward force while and immediately after passing over the vortex. These forces are caused due to the attractive pressure at the center of the vortex and downward currents in the downstream side of the vortex. These forces are considered to be remarkable in the evaluation of lifejackets in actual tsunamis.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66264875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electromyostimulation influences the mechanical properties and microarchitectures of bones beyond the stimulation site","authors":"I. S. Limbong, Tomoki Yamamura, Shigeo M. Tanaka","doi":"10.1299/JBSE.19-00034","DOIUrl":"https://doi.org/10.1299/JBSE.19-00034","url":null,"abstract":"Electromyostimulation is a nonpharmacological prevention method for osteoporosis that is safe and feasible for the elderly and people with physical disabilities. Our previous study demonstrated that random pulse train (RdPT) electromyostimulation of rat quadriceps induces an increase in the mechanical properties of the contralateral unstimulated femoral neck. However, the efficacy of this stimulation on other untested bones is still unclear. The objective of this research is to investigate the response of previously unstimulated bones to single-site electromyostimulation. The left quadriceps of rats were stimulated electrically by periodic pulse train (PrPT) or RdPT with 2 mA-magnitude pulses at 552 μs and a 50% duty ratio. The stimulation effect was examined on the diaphysis of long bones and lumbar vertebrae (L2–L5) by quasi-static mechanical tests and microcomputed tomography analysis. RdPT increased the strain energy at the stimulated left femur but did not change the properties of the other long bones. For the lumber vertebrae, on the other hand, both stimulations showed similar results. The stiffness of lumbar vertebra increased in L2, and the stiffness and the maximum load decreased in L4. Additionally, the BMC (bone mineral content), BV (bone volume), and TV (tissue volume) were reduced in L2, but not changed in L4. The other vertebrae were not affected by the stimulations. In conclusion, RdPT influences not only the stimulated femur, but also the lumbar vertebrae site-dependently as well as PrPT. These findings suggest the whole-body scale effect of electromyostimulation, however, which is not positive in all the bones, requiring further investigations for its clinical applications.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.19-00034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66265196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Orientation effects of bicuspid aortic valve with mild/severe aortic stenosis on aortic hemodynamics: a parametric study","authors":"T. Fujiwara, A. Barker, K. Sughimoto, F. Liang, Hao Liu","doi":"10.1299/JBSE.18-00417","DOIUrl":"https://doi.org/10.1299/JBSE.18-00417","url":null,"abstract":"While bicuspid aortic valve (BAV) shows different phenotypes associated with aortic aneurysm and valvular dysfunction due to aortic stenosis (AS), hemodynamics in patients with stenotic BAVs remains poorly understood. Here we address a study of the effects of valve phenotypes on aortic hemodynamics in different configurations of AS using an image-based subject-specific left ventricle (LV)-aorta integrated computational model. The model was built up by combining both MRI images and realistic motions of aortic valve, mitral valve, and LV apex as well as its contraction and dilatation of a healthy subject. Physiological boundary conditions were given based on a parameter-adjusted 0-1D cardiovascular model. Symmetrical BAV models with mild and severe stenosis were constructed with the orientation angle varying every 15° from 0° to 165° with regards to mitral valve while within a planar disc and the orientation effects on aortic hemodynamics were systematically investigated. Our results revealed that systolic jets in aorta were dominated by a combination of valve orientation and AS. Furthermore the hemodynamic indices of maximum wall shear stress (WSS), oscillatory shear index (OSI), and axial energy loss also demonstrated a feature of phenotype-and stenosis-dependency, pointing to the importance of taking into account the valve configuration in clinical decision-making on BAV patients.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.18-00417","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66264883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of initiating characteristics of osteoblastic calcium signaling responses to stretch by video rate time-course observation","authors":"Katsuya Sato, Manabu Katayama, S. Fujisawa, T. Nakahara, K. Minami","doi":"10.1299/JBSE.17-00519","DOIUrl":"https://doi.org/10.1299/JBSE.17-00519","url":null,"abstract":"Osteoblasts change their intracellular calcium ion concentration in response to mechanical stimuli. Although it has been reported that osteoblasts sense and respond to stretching of a substrate on which osteoblastic cells have adhered, the details of the dynamic characteristics of their calcium signaling response remain unclear. Motion artifacts such as loss of focus during stretch application make it difficult to conduct precise time-course observations of calcium signaling responses. Therefore, in this study, we observed intracellular calcium signaling responses to stretch in a single osteoblastic cell by video rate temporal resolution. Our originally developed cell-stretching microdevice enables in situ observation of a stretched cell without excessive motion artifacts such as focus drift. Residual minor effects of motion artifacts were corrected by the fluorescence ratiometric method with fluorescent calcium indicator Fluo 8H and fluorescent cytoplasm dye calcein red-orange. We succeeded to detect the intracellular calcium signaling response to stretch by video rate temporal resolution. The results revealed a time lag from stretch application to initiation of the intracellular calcium signaling response. We compared two time lags measured at two different cell areas: central and peripheral regions of the cell. The time lag in the central region of the cell was shorter than that in the peripheral region. This result suggests that the osteoblastic calcium signaling response to stretching stimuli initiates around the central region of the cell.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"13 1","pages":"17-00519-17-00519"},"PeriodicalIF":0.0,"publicationDate":"2018-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.17-00519","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42363999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing successful balance recovery from unexpected trips and slips","authors":"M. Brodie, Y. Okubo, D. Sturnieks, S. Lord","doi":"10.1299/JBSE.17-00558","DOIUrl":"https://doi.org/10.1299/JBSE.17-00558","url":null,"abstract":"Approximately one in three people over 65 years of age fall each year. The resulting physiological and psychological trauma can lead to physical deconditioning, social isolation and early mortality. Recent research has reported balance recovery can be trained in a single session resulting in dramatic reductions in fall rates. However, most previous research has used repeated exposures to a single hazard in a fixed location and not controlled for reductions in walking speed. It follows, that the biomechanical mechanisms important for reactive balance recovery (in the absence of anticipatory adjustments) are probably not well understood. Here, we investigated the biomechanics of successful reactive balance recovery following the first exposures to unexpected trip and slip hazards in different locations. Ten healthy adults (29.1±5.6 years) completed 32 walks at fixed speed, cadence and step length over a custom 10-meter walkway while being exposed to randomly presented and located slip and trip hazards. Balance recovery kinematics were assessed using a VICON motion analysis system. Repeated exposures to unexpected hazards induced significant reductions (p≤0.05) in anteroposterior (AP) trunk sway following the trips (26.7o to 14.3o; Cohen’s d -1.24) and slips (32.7o to 19.0o; Cohen’s d -0.93). During recovery from unexpected trips, reduced AP trunk sway was strongly correlated with a more posterior centre-of-mass position relative to the stepping foot (r=0.91) and a longer step length (r=-0.71). During recovery from unexpected slips, reduced AP trunk sway was moderately correlated with slower slipping speed (r=0.54) and a less posterior centre-of-mass position relative to the stance (slipping) foot (r=-0.39). The biomechanical mechanisms required for the successful reactive balance recovery from trips and slips were different. Future experimental protocols to optimize reactive balance recovery for fall prevention should therefore use progressive exposures to both slip and trip hazards using specialized equipment and determine if similar biomechanical mechanisms are observed in young and elderly people at risk of falls.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"13 1","pages":"17-00558-17-00558"},"PeriodicalIF":0.0,"publicationDate":"2018-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.17-00558","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44498469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating the influence of age-related changes in skin stiffness on tactile perception for static stimulations","authors":"Toru Hamasaki, Yamaguchi Takahiro, M. Iwamoto","doi":"10.1299/JBSE.17-00575","DOIUrl":"https://doi.org/10.1299/JBSE.17-00575","url":null,"abstract":"It is difficult to experimentally observe the influence of differences in individual skin properties of human fingers on tactile perceptions. During subjective experiments, many parameters, such as skin properties, the transmittance of nerve signals, and individual feelings are intricately mixed; therefore, it is difficult to identify which elements are affected and to what extent. It has not been determined how age-related changes in the stiffness of skin influence tactile perceptions. We developed a two-dimensional cross-section human fingertip finite element model based on previous studies. Then, we estimated the influence of age-related changes in skin stiffness on Merkel cells and tactile perceptions by using finite element analysis. Age-related changes in skin stiffness were described by changing skin material properties in the model. Simulations using a model involving the fingertip being contacted with a rigid flat plate or a 2-point indenter were performed. Using a rigid flat plate and standard skin material properties, the contact width between the finger pad and the object was 5 mm. Meanwhile, the width changed from 5 mm to 4 mm when using a model of age-related changes of skin. Using a rigid 2-point indenter, the difference in the peak-to-valley of the Mises distribution around the Merkel cells indicated 2-point discrimination. Besides, the difference decreased by approximately 43% with changes in skin stiffness. These results indicated that age-related changes in skin stiffness influenced tactile perceptions.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"13 1","pages":"17-00575-17-00575"},"PeriodicalIF":0.0,"publicationDate":"2018-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.17-00575","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41579447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of argon ion-implantation on mechanical and degradation properties of bulk-shaped poly(lactic acid)","authors":"M. Sakaguchi, Satoshi Kobayashi, Y. Teranishi","doi":"10.1299/JBSE.18-00239","DOIUrl":"https://doi.org/10.1299/JBSE.18-00239","url":null,"abstract":"Surface treatment of PLA has been investigated to increase degradation rate due to improvement in hydrophilicity. Zhang et al . reported that the surface hydrophilicity of the PLA was improved by electron beam irradiation (Zhang, et al., 2010). The improvement in hydrophilicity might be due to increase hydrophilic groups which was occured by chain scission induced by electron beam irradiation. Wang et al . reported that the surface hydrophilicity of the poly-ether-ether-ketone (PEEK) was improved by ion-implantation. It is explanted that the cause of this hydrophilicity improvement was construct hydroxyl groups as well as ravine structure, which increase specific surface area (Wang, et al., 2014). Moreover, surface properties can be adapted by Abstract Poly(lactic acid) (PLA) has attracted much attention as a material for bioabsorbable bone fixation devices, however degradation rate of PLA is very low. Surface treatment of PLA has been investigated to increase degradation rate due to improvement in hydrophilicity. In this study, effects of ion-implantation on degradation rate and mechanical properties were investigated. Argon gas which is chemically stable was used as ion source, and argon ion was implanted in the surface of PLA. The contact angle and the surface roughness of the ion-implanted PLA were measured to evaluate hydrophilicity, and tensile tests and micro-indentation tests were conducted to evaluate mechanical properties. The difference in surface morphology after in vitro degradation test between ion-implanted and un-implanted region was observed to investigate degradation properties of ion-implanted PLA. As a result, tensile strength increased by 8.2 % compared to un-implanted specimen and Vickers hardness increased by 9.5%. The ion-implantation might affect mechanical properties in the overall specimen rather than those in the surface. The result of in vitro degradation test showed that an initial degradation rate was accelerated by ion-implantation. This result is consistent with the increasing hydrophilicity of ion-implanted PLA. Those results suggested that ion-implantation accelerates degradation of PLA without decreasing mechanical properties.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"13 1","pages":"18-00239-18-00239"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.18-00239","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66264862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of a cavitating jet for removing dental plaque from the surface of the screw of an implant and its practical application","authors":"Junki Yamada, Kewen Peng, Tomoyuki Kokubun, T. Takiguchi, Gensheng Li, Matsuo Yamamoto, H. Soyama","doi":"10.1299/JBSE.17-00102","DOIUrl":"https://doi.org/10.1299/JBSE.17-00102","url":null,"abstract":"Dental plaque on the surfaces of implants causes peri-implantitis and periodontitis. Although the plaque needs to be removed from the surfaces, it is difficult to clean it from the screw section of an implant, as this is roughened to improve biocompatibility. Recently, a method using a cavitating jet was proposed to clean dental plaque. In this paper, the geometry of a Venturi type nozzle for a cavitating jet is optimized by measuring the cavitation impact using a PVDF (Polyvinylidene Fluoride) sensor. The cleaning performance of a cavitating jet using this nozzle is compared with that of a normal water jet. The results show that the optimum divergence angle is 15 deg or 20 deg, depending on the injection pressure. The effect of temperature on the impact power was also investigated, and it was found that the impact power increases with water temperature and saturates at 40-50 °C. It was demonstrated that a cavitating jet using the optimized Venturi type nozzle can remove dental plaque from the screw section of an implant and that the area cleaned by the cavitating jet is greater than that cleaned by a normal water jet.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"13 1","pages":"17-00102-17-00102"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1299/JBSE.17-00102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66264142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Ca or Mg ion irradiation on the bioactivity and strength of hydroxyapatite","authors":"Satoshi Kobayashi, Tomomi Izawa, Y. Teranishi, Yoshimi Ohyabu","doi":"10.1299/JBSE.18-00036","DOIUrl":"https://doi.org/10.1299/JBSE.18-00036","url":null,"abstract":"In order to improve bioactivity of hydroxyapatite (HA), the surface of HA was modified with calcium or magnesium ion irradiation. Calcium ion irradiation improved bioactivity of HA up to ion dose 10 ions/cm, whereas magnesium ion irradiation did not affect bone-like apatite formation. It is found that this different phenomena were attributed to surface electrical potential. Ion irradiation generally induces surface nano-scopic damage, however the strength of HA was not significantly affected by ion irradiation. From cell proliferation, no toxicity of HA irradiated with calcium ions was confirmed. From these results, the effectiveness of calcium ion irradiation on the treatment of bone defect using HA is confirmed.","PeriodicalId":39034,"journal":{"name":"Journal of Biomechanical Science and Engineering","volume":"13 1","pages":"18-00036-18-00036"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66264291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}