Investigation of blood pulse PPG signal regulation on toe effect of body posture and lower limb height

Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position.

Human Body Modeling and Posture Simulating Based on 3D Surface Scan Data

This paper presents a new approach for modeling the human body by considering the motion state and the shape of whole body. The body model consists of a skeleton kinematic model and a surface model. The former is used to determine the posture of the body,and the latter is used to generate the body shape according to the given posture. The body surface is reconstructed with multi-segment B-spline surfaces based on the 3D scan data from a real human body.Using only a few joints parameters and the original surface scan data, the various body postures and the shape can be generated easily. The model has a strong potential of being used for ergonomic design,garment design, virtual reality environment, as well as creating human animation, etc.

A Human Body Posture Recognition Algorithm Based on BP Neural Network for Wireless Body Area Networks

Human body posture recognition has attracted considerable attention in recent years in wireless body area networks(WBAN). In order to precisely recognize human body posture,many recognition algorithms have been proposed.However, the recognition rate is relatively low. In this paper, we apply back propagation(BP) neural network as a classifier to recognizing human body posture, where signals are collected from VG350 acceleration sensor and a posture signal collection system based on WBAN is designed. Human body signal vector magnitude(SVM) and tri-axial acceleration sensor data are used to describe the human body postures. We are able to recognize 4postures: Walk, Run, Squat and Sit. Our posture recognition rate is up to 91.67%. Furthermore, we find an implied relationship between hidden layer neurons and the posture recognition rate. The proposed human body posture recognition algorithm lays the foundation for the subsequent applications.

Relationship of proprioception,cutaneous sensitivity,and muscle strength with the balance control among older adults

Background:Balance impairment is one of the strongest risk factors for falls.Proprioception,cutaneous sensitivity,and muscle strength are 3 important contributors to balance control in older adults.The relationship that dynamic and static balance control has to proprioception,cutaneous sensitivity,and muscle strength is still unclear.This study was performed to investigate the relationship these contributors have to dynamic and static balance control.Methods:A total of 164 older adults(female=89,left dominant=15,age:73.5±7.8 years,height:161.6±7.1 cm,weight:63.7±8.9 kg,mean±SD)participated in this study.It tested the proprioception of their knee flexion/extension and ankle dorsi/plantarflexion,along with cutaneous sensitivity at the great toe,first and fifth metatarsals,arch,and heel,and the muscle strength of their ankle dorsi/plantarflexion and hip abduction.The Berg Balance Scale(BBS)and the root mean square(RMS)of the center of pressure(CoP)were collected as indications of dynamic and static balance control.A partial correlation was used to determine the relationship between the measured outcomes variables(BBS and CoPRMS)and the proprioception,cutaneous sensitivity,and muscle strength variables.Results:Proprioception of ankle plantarflexion(r=-0.306,p=0.002)and dorsiflexion(r=-0.217,p=0.030),and muscle strength of ankle plantarflexion(r=0.275,p=0.004),dorsiflexion(r=0.369,p<0.001),and hip abduction(r=0.342,p<0.001)were weakly to moderately correlated with BBS.Proprioception of ankle dorsiflexion(r=0.218,p=0.020)and cutaneous sensitivity at the great toe(r=0.231,p=0.041)and arch(r=0.285,p=0.002)were weakly correlated with CoP-RMS in the anteroposterior direction.Proprioception of ankle dorsiflexion(r=0.220,p=0.035),knee flexion(r=0.308,p=0.001)and extension(r=0.193,p=0.040),and cutaneous sensitivity at the arch(r=0.206,p=0.028)were weakly to moderately correlated with CoP-RMS in the mediolateral direction.Conclusion:There is a weak-to-moderate relationship between proprioception and dynamic and static balance control,a weak relationship between cutaneous sensitivity and static balance control,and a weak-to-moderate relationship between muscle strength and dynamic balance control.

Appropriate posture of cancer patients treated with PICC to prevent internal jugular vein ectopic

We aimed to study the appropriate posture of peripherally inserted central catheter （PICC） patients, to reduce the incidence of internal jugular vein heterotopia. Methods： From 2009 to 2013, a total of 290 cases with PICC were enrolled in our study. They were divided into two groups. The patients in control group took regular position, which mean pros- tration, upper limb of tube side was abduction 90°, head moved to puncture side in order to block the internal jugular vein. On the basis of conventional body position putting, posture of patients in observation group was improved, the head remain neutral, and had 180° angle with trunk longitudinal axis, not favor any side. After ensuring the upper limb abduction, had 90° angle with the trunk, then catheter was inserted slowly. The jugular venous catheter heterotopia rate was judged by X.ray results. Results： The jugular venous catheter heterotopia rate of control group and observation was 12.8% and 0.68%, respectively. The difference between two groups was statistically significant （P 〈 0.01）. Conclusion： The body posture improvement can prevent discomfort of patients and reduce the jugular venous catheter heterotopia rate of PICC.

扶正补土皮内针法联合康复训练治疗脑卒中后肩手综合征Ⅰ期临床观察

目的研究扶正补土皮内针法联合康复训练对缺血性脑卒中后肩手综合征(SHS)Ⅰ期的影响。方法选取62例卒中后SHSⅠ期患者,随机分为试验组和对照组,每组31例;对照组实施康复训练,试验组则实施扶正补土皮内针治疗联合康复训练。运用简式Fugl-Meyer评分、视觉模拟量表(VAS)评分、手部水肿评分评估两组患者的上肢运动功能、疼痛情况及手部水肿程度,并比较临床疗效。结果治疗后,试验组患者简式Fugl-Meyer评分、VAS评分、水肿评分均优于对照组(P<0.05)。试验组治疗总有效率为90.32%(28/31),高于对照组的67.74%(21/31)(P<0.05)。结论扶正补土皮内针法联合康复训练可改善缺血性脑卒中后SHSⅠ期患者的肩部疼痛及水肿程度并促进上肢运动功能的恢复。

姿态对家畜体尺测量的影响及优化策略

家畜体尺是育种和管理的重要基础数据,但传统测量方法存在效率低、应激大、误差高等问题;非接触式测量方法虽具潜力,但家畜姿态引起的测量变异度显著影响其精准性,是影响非接触式体尺测定准确度的重要因素之一。本文主要综述了不同类型非接触式测量方法在体尺测定方面的应用、误差来源,以及提高非标准姿态测定准确度的方法和实现路径以及应用场景,以期为家畜非接触式精准测量的发展提供参考。

Stable walking of quadruped robot on unknown rough terrain

Quadruped robot is considered to be the most practical locomotion machine to negotiate uneven terrain, and shows superb stability during static walking. To improve the ability to go over rough terrain, this paper is focused on the stable walking and balance control of quadruped robots. 24 kinds of walking gaits are analyzed in order to derive the most stable and smoothest walking gait. Considering the inefficiency to model a terrain by its specified appearance, a uniform terrain model is established and by means of kinematic analysis, a method to adjust the body posture and center of gravity （COG） height is presented. Simulations demonstrate the effectiveness of the proposed meth- od and the improvement of the adaptation of quadruped robots on rough terrain.

A Review of Data Acquisition System based on LabVIEW

With the continuous development and expansion of automotive industry, car safety problems are widely concerned by most of us. In order to make it easier to adjust car′s real-time body posture, it is necessary to design a real-time data acquisition system, thus reducing the number of casualties in normal driving. A brief account of the development status of data acquisition system at home and abroad, and the concept, principle,function of virtual instrument platform are given. The advantages and disadvantages of the data acquisitionsystem, based on LabVIEW in different methods of data acquisition, are analyzed and compared, and put forward some improvements and optimization, so the real-time data acquisition system can meet the requirement of adjusting the state of the vehicle, improving real-time of data acquisition and processing. Finally, it indicates the development direction and prospect of data acquisition system based on LabVIEW.

Computation of Magnetic Anomalies and Gradients for Spatial Arbitrary Posture Regular Body

In the interaction computation for 3D gravity and magnetic anomalies due to arbitrarily shaped homogenous magnetized polyhedron model composed of triangular facets, there are many difficult points, such as mass computing, absence of a mature computer technique in 3D geological body modeling, inconvenient human-computer interaction, hard program coding, etc.. Based on the formulae of the magnetic field due to horizontal regular bodies, and by applying forward theory with the three-dimensional Cartesian coordinate system transformation, the forward problems of magnetic anomalies and gradient tensors for arbitrary slantwise regular bodies were solved. It is shown that the magnetic calculating expressions of the arbitrary posture regular body are corrected by comparing results with the homogeneous polyhedral body model outcome data. Furthermore, in the same condition, the former significantly reduced forward time. Applying a new forward method of regular body expressions in arbitrary posture, developed software for interaction computation between the 3D geological body model and magnetic field has advantages of fast calculation speed, easy manipulation, etc..

术前体位复位联合术中提拉复位辅助Mis-TLIF技术治疗峡部裂型腰椎滑脱

目的:探讨应用微创经椎间孔腰椎椎间融合术(minimally invasive transforaminal lumbar interbody fusion,Mis-TLIF)结合术前体位复位治疗峡部裂型腰椎滑脱的临床效果并总结其优点。方法:回顾性分析2016年7月至2022年7月收治的60例腰椎峡部裂型滑脱患者,其中男26例,女34例;年龄35~72(51.32±4.24)岁。依据手术方式分为观察组和对照组。观察组30例,男12例,女18例;年龄35~71(51.80±6.38)岁;病程12~60(24.17±1.98)个月;L4滑脱18例,L5滑脱12例;Meyerding分级Ⅰ度滑脱20例,Ⅱ度滑脱10例;采用术前体位复位联合术中撑开复位后经Quadrant通道Mis-TLIF。对照组30例,男14例,女16例;年龄36~72(50.00±4.24)岁;病程12~60(23.70±1.53)个月;L4滑脱16例,L5滑脱14例;Meyerding分级Ⅰ度滑脱19例,Ⅱ度滑脱11例;采用传统后路开放椎体融合术治疗。分析两组的手术时间、术中及术后出血量、术后住院时间、放射线暴露时间和并发症等方面的差异。采用视觉模拟评分(visual analogue scale,VAS)、Oswestry功能障碍指数(Oswestry disability index,ODI)及日本骨科协会(Japanese Orthopaedic Association,JOA)评分(腰椎评分标准)评估临床效果,随访复查X线及CT评估椎间融合情况。结果:所有患者获得12个月的随访。两组在手术时间、腰痛VAS、滑脱角、滑脱率等方面差异无统计学意义(P>0.05)。观察组术中术后出血量(165.50±15.56)、(59.17±10.59)ml,均少于对照组(259.33±35.32)、(165.33±29.56)ml(P<0.05);观察组住院时间(3.53±0.68)d,少于对照组(5.20±0.41)d(P<0.05);末次随访时两组椎间隙高度、滑脱角、滑脱率、ODI、VAS、JOA评分均较术前明显改善(P<0.05)。末次随访观察组与对照组ODI[(9.93±1.11)%vs(10.93±1.11)%]和JOA[(26.07±1.01)分vs(25.43±1.25)分]比较,差异有统计学意义(P<0.05)。结论:在峡部裂型腰椎滑脱的治疗中,术前体位复位联合术中提拉复位辅助Mis-Tlif技术相比传统开放性手术具有创伤小、出血少、住院周期短等优点,是一种安全有效的技术。

手术沙滩椅体位摆置标准作业程序的建立及应用

目的研究手术沙滩椅体位(beach chair position,BCP)摆置标准作业程序(standard operation procedure,SOP)的建立及应用。方法采用方便抽样的方法,选取2020年10—12月厦门大学附属第一医院收治的16例肩关节镜手术患者为对照组,以对等原则选取2021年1—3月收治的16例患者为观察组。对照组按常规手术体位摆置;观察组按BCP摆置SOP实施摆置。比较2组摆置时间、团队协作熟悉度及医生满意度,并就对手术BCP摆置SOP进行评价。结果观察组手术体位摆置时间为(471.81±52.41)s,短于对照组的(719.13±66.94)s(P<0.05);观察组手术医生的满意度高于对照组,手术团队协作熟悉度评分高于对照组,差异有统计学意义(P<0.05)。2组麻醉医生满意度比较,差异无统计学意义(P>0.05)。团队成员对手术BCP摆置SOP评价认可度均较高。结论手术BCP摆置SOP的建立及应用使手术体位护理规范化、标准化、同质化,有效提高手术室护理质量和工作效率。

LQG-IMC集成的空气悬架车身俯仰姿态控制策略研究

为了提高空气悬架车辆在非紧急工况下的整车性能和车身姿态,建立了刚度可调空气悬架车辆半车纵向行驶动力学模型,结合LQG控制与IMC控制的优缺点,设计了空气悬架LQG-IMC集成控制器,并引入粒子群算法来优化了IMC时间常数。应用MATLAB/Simulink搭建了仿真模型,仿真了初始速度30m/s、B级路面和非紧急制动工况。结果表明,与被动悬架相比LQG-IMC集成控制空气悬架车辆的车身俯仰角、前悬架及后悬架的动挠度均方根分别改善了56.44%、53.33%和63.71%,且车身姿态得到进一步控制,为空气悬架控制器的开发奠定了理论基础。

青年男性颈肩部轮廓量化分析与形态匹配

以190名青年男大学生为研究对象,通过照片测量法、三维人体扫描法获取人体正侧面照片及三维点云数据。基于三维点云数据,提取颈肩部轮廓曲线进行椭圆傅立叶拟合得到椭圆系数,经主成分分析和聚类分析,将青年男性颈肩部正侧面形态各分为3类。采用角度半径和欧几里得距离实现二维照片与三维点云数据之间的匹配,并验证匹配准确率。结果显示:颈肩部正面轮廓匹配验证准确率达92.5%,侧面轮廓匹配验证准确率达95.0%。该研究为基于人体照片的人体形态研究提供了理论依据。

体医结合背景下高校女大学生异常身体姿态现状调查与运动处方的制定研究

文章从体医结合背景出发,结合运动处方的实施效果和现实意义,通过对高校女大学生异常身体姿态现状调查,了解当代女大学生的生活习惯等对体态的影响,根据大学生自身情况和锻炼需求,借鉴运动处方在全民健身中推广应用的经验与模式,以科学健身为原则,加强对女大学生身体姿态的重视程度,为女大学生提供运动处方的计划方案,有利于提高女大学生的体质健康水平。

针灸联合精细化体位管理治疗脑卒中后肩手综合征Ⅰ期患者的效果

目的探讨针灸联合精细化体位管理治疗脑卒中后肩手综合征Ⅰ期患者的效果。方法选取2021年7月至2023年1月于江西省人民医院康复医学科就诊的128例脑卒中后肩手综合征Ⅰ期患者为研究对象,按照随机数字表法分为对照组与观察组,每组各64例。对照组患者给予西药联合精细化体位管理治疗,观察组患者实施针灸联合精细化体位管理治疗,两组均治疗4周。比较两组患者的临床疗效、疼痛程度、上肢运动功能、生活自理能力。结果观察组的临床疗效优于对照组,差异有统计学意义(P<0.05)。治疗前,两组患者的Fugl-Meyer评测法(FMA)、关节活动度、改良巴氏指数(BI)、视觉模拟评分法(VAS)评分比较,差异无统计学意义(P>0.05);治疗后,观察组的FMA[(59.44±5.82)分]、关节活动度[(90.35±13.14)°]、BI[(84.79±8.44)分]均高于对照组[(50.14±5.03)分、(80.52±11.97)°、(65.18±7.21)分],观察组的VAS评分[(1.14±0.22)分]低于对照组[(2.36±0.35)分],差异有统计学意义(P<0.05)。结论针灸联合精细化体位管理可有效缓解脑卒中后肩手综合征Ⅰ期患者患肢肿胀、疼痛症状,有利于提升患者的上肢运动功能,促进患者生活自理能力提升。

改良体位对乳腺手术过程及效果的影响

目的分析改良体位对乳腺手术过程及效果的影响。方法选择2019年1月至2021年1月接受乳腺手术治疗的86例患者作为研究对象,按数表法将其分为对照组与观察组,每组43例。对照组患者在手术治疗过程中采取常规仰卧位;观察组患者则将腋窝抬高,使腋后线、头顶部均与床边缘对齐,医护人员在手术操作过程中适当调整操作位置、方式。对2组手术实施过程中的相关指标(手术时间、术中出血量、无影灯调节次数)、术后并发症发生率、肩关节活动度及其达标率进行比较。结果对照组的手术时间长于观察组(t=3.340,P<0.05),其术中出血量、无影灯调节次数均多于观察组(t=2.752、t=3.263,P<0.05);对照组术后并发症发生率高于观察组,肩关节活动度达标率低于观察组(χ^(2)=5.460、χ^(2)=4.914,P<0.05);2组术后1天肩关节活动度无明显差异(P>0.05),术后2个月,对照组肩关节的前屈、外旋、内收、内旋、外展、后伸的活动度均小于观察组(t=2.985、t=2.760、t=3.506、t=2.988、t=3.630、t=2.246,P<0.05)。结论对于采用乳腺手术治疗者,术中对其进行改良体位指导可以缩短手术时间,减少术中出血量及无影灯调节次数,并降低术后并发症发生率,有利于患者肩关节功能的恢复。

医学院校在职教师不良体态现况及其影响因素分析

目的了解医学院校在职教师的不良体态现状及其影响因素。方法采用多阶段抽样方法,于2020年11~12月对海南医学院的174名在职教师开展调查。采用站位静态体态评估法进行体态评估,通过问卷调查收集其基本信息、生活习惯和不良体态认知等。采用χ2检验和二分类Logistic回归进行统计分析。结果174名在职教师中不良体态粗检出率为59.2%,调整年龄构成后标准化检出率为68.4%;随着年龄增长,检出率逐渐增加,35岁以下、35~44岁、45岁及以上年龄组的不良体态检出率分别为48.4%、71.4%和73.9%;调整混杂因素后,二分类Logistic回归分析结果显示,不良体态的影响因素为经常感到疲劳、经常穿高跟鞋、经常交叉两腿站立、年龄和日均静坐时间;不良体态检出率随着年龄、日均静坐时间增加而增加(P<0.05),而不良体态认知率为28.4%,年龄组间比较无统计学意义(P>0.05)。结论医学院在职教师人群不良体态检出率较高,且随年龄和日均静坐时间递增,同时知晓率偏低,45岁及以上久坐教师更应加强对不良体态相关知识的学习,防止因不良体态问题继续恶化而导致更为严重的健康问题。

身体姿势如何影响沉浸式虚拟现实环境下的学习?——基于学习者的空间能力视角

在沉浸式虚拟现实(Immersion Virtual Reality,IVR)应用于提升学习效果的过程中,学习者的空间能力与身体姿势是重要的影响因素。基于此,文章首先从学习者的空间能力视角,通过分组对比实验探究IVR环境下不同空间能力学习者的身体姿势对学习的影响,结果发现:低空间能力学习者为追求良好的学习体验时可选择站位姿势,为获得更好的学习效果时可选择坐位姿势;高空间能力学习者不同的身体姿势对学习影响不大,但采用坐位姿势可以维持平和的情绪状态。之后,文章通过结构方程模型分析,揭示了不同空间能力学习者的身体姿势影响学习的路径:低空间能力学习者的站位姿势通过提升沉浸感、存在感与结果性积极情绪改善学习体验,坐位姿势则可直接提升学习效果;高空间能力学习者的坐位姿势可提升过程性中性情绪,存在感的提升也可直接提升学习效果,并通过提升沉浸感来增强结果性积极情绪。最后,文章针对IVR环境的设计与教学应用提出相关建议,以期促进IVR及教育元宇宙的良性发展,从而助推我国的教育数字化转型。

基于极径的青年女性肩胸腰部形态表征及差异性分析

为表征同一号型下的人体体型形态差异,选取与原型样板密切关联的肩部、胸部及腰部水平特征截面进行研究。通过[TC]^(2)获取145名18~25岁青年女性的三维点云数据,选取占比最高的160/84 A体型样本,采用K-means聚类进行体型细分,提取肩部、上胸围、胸围、下胸围、腰围5层水平特征截面,运用极径表征形态差异。研究结果表明:同一国标号型身高胸围数据虽然相似,但存在形态差异;160/84 A体型可分为圆厚体、宽扁体、中等体,分别占比7.69%、53.85%及38.64%。3类体型中宽扁体肩宽>中等体肩宽>圆厚体肩宽,肩点处最大极差为3.82 cm。圆厚体的上胸围厚、胸围厚和下胸围厚最厚,其次是中等体胸围厚,宽扁体的胸围厚最薄,在前中处最大极差分别为3.22、3.62和2.97 cm。宽扁体较圆厚体、中等体肩点位置向前中方向偏移10°,宽扁体、中等体胸点位置较圆厚体向侧缝方向偏移10°~20°。