血氧含量和血流量变化光纤检测系统的研制

提出了一种利用内耳血氧含量及血流量变化作为检测参数的测量系统.在波长分别为660 nm和810 nm处,利用氧合血红蛋白和脱氧血红蛋白对近红外光的吸光系数不同的原理,依据朗伯-比尔定律推导出适于测量血氧含量及血流量变化的工程公式,设计的传感器实现了测量内耳组织血氧饱和度和血流量变化两种人体生理信号的采集和转换.该系统通过输送数据到PC机,实时反映二者的关系,实验结果表明,在20%～100%血氧饱和度范围内,测量精度为3%,从而为人体眩晕判断提供了较有力的理论依据.     

基于近红外光谱的抗扰动脑血氧分析仪

研究了一种近红外光谱抗扰动脑血氧分析仪,用于解决常规脑血氧测试方法检测过程复杂、抗干扰措施繁琐等问题。分析与探讨了影响脑血氧检测精度的因素,选择了合适的三波长近红外探测光源(735nm/805nm/850nm)用于该系统。利用氧合血红蛋白和还原血红蛋白在近红外光波段的吸收特性,得到这两种物质的浓度变化量,推算出了影响血氧检测精度的源端干扰表达式。同时,在检测端同步检测环境光,消除了漏光干扰。最后对上位机得到的原始数据与干扰数据进行处理,实现对大脑前额叶脑血氧波动的实时监测。设计了屏气实验以及源端干扰实验,检验了仪器实验结果的正确性。结果表明:本文所设计的脑血氧分析仪可以有效地检测血红蛋白的变化并能通过源端校正算法抑制源端干扰,干扰抑制比可达70%以上,基本实现了对人体无创、实时、准确监测的目的。     

EGOS-600近红外组织血氧参数无损监测仪在人体解剖生理学实验教学中的应用

组织血氧仪能无损的监测人体各部位的组织血氧变化情况。苏州爱琴生物医疗电子有限公司生产的EGOS-600系列近红外组织血氧参数无损监测仪被用于人体解剖生理学实验中进行多种条件下的血氧监测。文章简介了血氧仪的性能、参数、功能特点和界面等。详细写明了组织血氧仪生理学实验的步骤。设计并使用了基于matlab的实验结果处理和显示界面。     

脉搏血氧饱和度测量系统的设计研究

本文设计了一种脉搏血氧饱和度测量系统,它采用调制光及同步检波方法取代传统的直流光,通过分析测试部位的血液随脉搏波动引起光吸收的变化推算出人体血氧饱和度(SO_2)。通过10例患者临床实验表明,本系统同临床血氧测定仪HP-56S测量结果有很高一致性,相关系数达到0.932。     

基于光电容积脉搏波法血氧饱和度测量系统研究

血氧饱和度是人体一项重要的生理参数。目前,血氧饱和度检测方法分为有创血氧饱和度检测和基于光电容积脉搏波法的无创血氧饱和度检测。其中,基于光电容积脉搏波法的无创血氧饱和度研究模型采用人体光电容积脉搏波信号作为信息载体进行无创连续的血氧饱和度的检测。该文综述了基于血液容积波法无创血氧饱和度测量原理及测量系统;重点介绍了反射式血氧饱和度检测系统;并对影响血液容积波法无创血氧饱和度测量系统准确性的相关因素进行了归纳与总结。     

基于LCTF多光谱成像的人体指甲特征光谱提取

利用由液晶可调谐滤光片(LCTF)和CCD相机组成的多光谱成像系统在450～1 000 nm光谱范围内每隔10 nm采集人体指甲样本,得到包含56个波段的人体指甲多光谱图像。通过参考白板比较测量法进行反射率反演,得到指甲的准确反射率信息,分别利用主成分分析法(PCA)和波段指数法实现样本图像的降维,得到两个特征空间,并利用光谱角度填图法(SAM)在两个特征空间内对人体指甲进行分类,分类准确度分别为92.5%及82.9%。因此,由主成分分析法得到的特征空间可以作为人体指甲的特征光谱,为指甲多光谱图谱分析和人体健康评估提供了可靠的依据。     

无创血氧饱和度检测仪的研究

传统的组织血氧饱和度测量方法是有创测量,且很难做到连续测量,因此研究一种无创、连续测量血氧饱和度的方法具有重要意义。文章根据红光和红外光透过人体动脉血管后不同的传输特性,计算出人体的血氧饱和度。硬件上以MSP430为核心,实现了信号的产生和测量电路;软件上实现了血氧饱和度的复杂算法,并有效地克服了测量信号的漂移。该系统无创测量,既减轻了病人的痛苦,又可以实时监控,具有低成本、结构合理、制作简单、安全可靠等优点,满足了临床监护的需求。     

基于智能终端的血氧信号采集装置设计

血氧饱和度是指血液中氧合血红蛋白(Hb O2)的容量占全部血红蛋白(Hb)容量的百分比,即血液中血氧的浓度。通过对人体血氧饱和度的检测,能够有效的判断人体循环系统和呼吸系统的功能是否正常。目前指夹透射式检测技术发展已相对成熟,但这种检测方法,只适用于对住院病人的监护,而无法进入社区乃至家庭。因此本文基于对反射式血氧饱和度的实时检测硬件装置的研究,结合消除干扰的算法,设计出一种适用于家庭和社区的基于智能终端便于携带的血氧饱和度检测装置。     

基于无线传输的脉搏血氧饱和度采集节点设计

近年来,慢性疾病人数骤增与医疗资源匮乏之间的矛盾引起了无线体域网在医疗领域的广泛应用。将透射式指端脉搏血氧饱和度采集节点与Android智能终端系统相结合,对光电容积脉搏波进行采集,利用近红外光谱吸光度强弱与物质化学成分信息之间呈现线性相关的特性,对人体体征参数中的脉率和血氧饱和度进行检测。实验结果表明,该节点体积小,功耗低,抗干扰性强,能够无创伤,快速准确地对脉率和血氧饱和度进行实时性监测,并实现数据的无线传输,适合在家庭中使用。     

3D打印最小产品记忆性耳蜗植入有望使用

汉诺威激光中心是一个独立的、非盈利的研究机构组织,中心的科学家们使用3D打印技术生产出带有记忆功能和复杂形状的微型植入物,如人体内耳的耳蜗。     

禽蛋检测与分级智能机器人系统的设计

为了实现禽蛋检测与分级的自动化,建立一种轻型自动化系统,即禽蛋检测与分级智能机器人系统(System of intelligentrobot detecting and grading eggs,SmDGE).SIRDGE将禽蛋的破损检测、内部品质检测以及检测和分级时的搬运工作联系起来,统一由一个关节型机器人来完成,能实现禽蛋检测和分级的全程自动化.介绍该系统的组成结构和工作原理,对系统关键的硬件设备和软件实现过程作了必要的说明,包括场景图像的采集和摄像机的标定,图像处理和特征值的提取,机器人运动控制和轨迹规划,真空吸盘的单片机控制,敲击声音的处理与破损检测,彩色图像处理与内部品质检测等内容,并对SIRDGE系统进行性能测试,测试结果证明,SIRDGE能够实现禽蛋检测和分级的全程自动化.     

高压细水雾灭火喷嘴的雾化特性研究

高压细水雾灭火系统是采用纯水液压技术的新型灭火装置,具有无环境污染、灭火迅速、用水量少和水渍损失极小等优点,是目前国际上推祟的哈龙替代系统。运用轴对称射流边界层动量积分法,对系统关键执行元件—直射式雾化喷嘴的内部流动进行分析,对边界层厚度δ和加速因子K这两个内部流动参数进行考查;同时对一些与灭火效果有关的外部雾化特性参数如出口速度和雾滴平均粒径SMD等进行分析,得出压力是影响外部雾化特性参数的最关键因素。认为8~9 Mpa是所设计喷嘴的最低稳定雾化工作压力区域。同时,喷嘴结构参数收缩角α、收缩段长度l/d对内部流动参数、外部雾化特性参数均有影响,但不明显。试验验证了上述分析结果,优选出了适合的喷嘴内部结构。     

Improved instrumentation for blood flow velocity measurements in the microcirculation of small animals

Microcirculation is the generic name of vessels with internal diameter less than 100 microm of the circulatory system, whose main functions are tissue nutrition and oxygen supply. In microcirculatory studies, it is important to know the amount of oxyhemoglobin present in the blood and how fast it is moving. The present work describes improvements introduced in a classical hardware-based instrument that has usually been used to monitor blood flow velocity in the microcirculation of small animals. It consists of a virtual instrument that can be easily incorporated into existing hardware-based systems, contributing to reduce operator related biases and allowing digital processing and storage. The design and calibration of the modified instrument are described as well as in vitro and in vivo results obtained with electrical models and small animals, respectively. Results obtained in in vivo studies showed that this new system is able to detect a small reduction in blood flow velocity comparing arteries and arterioles (p <0.002) and a further reduction in capillaries (p<0.0001). A significant increase in velocity comparing capillaries and venules (p <0.001) and venules and veins (p <0.001) was also observed. These results are in close agreement with biophysical principles. Moreover, the improvements introduced in the device allowed us to clearly observe changes in blood flow introduced by a pharmacological intervention, suggesting that the system has enough temporal resolution to track these microcirculatory events. These results were also in close conformity to physiology, confirming the high scientific potential of the modified system and indicating that this instrument can also be useful for pharmacological evaluations.     

A scanning x-ray imaging system for quantitative arteriography and blood flow measurements

The authors have developed a new x-ray imaging system for quantitative arterial imaging and blood flow measurements. The system is based on the scanned projection technique and employs an x-ray beam collimated into a fan of radiation and an x-ray image intensifier optically coupled to a 1024-element linear photo-diode detector array. The system has two modes of operation: quantitative projection imaging and blood flow measurements. In the first mode of operation, low-noise, quantitative images are obtained by irradiating small regions of interest to minimize the detection of scattered radiation and intensifier tube veiling glare. System performance is optimized by making use of the large dynamic range (8,000:1) and response linearity of the solid-state photo-detector. In the second mode of operation, flow information is obtained by detecting the passage of a small bolus of iodine contrast agent.     

Investigation of inner ear anatomy in mouse using X‐ray phase contrast tomography

A thorough understanding of inner ear anatomy is important for investigators. However, investigation of the mouse inner ear is difficult due to the limitations of imaging techniques. X‐ray phase contrast tomography increases contrast 100–1,000 times compared with conventional X‐ray imaging. This study aimed to investigate inner ear anatomy in a fresh post‐mortem mouse using X‐ray phase contrast tomography and to provide a comprehensive atlas of microstructures with less tissue deformation. All experiments were performed in accordance with our institution's guidelines on the care and use of laboratory animals. A fresh mouse cadaver was scanned immediately after sacrifice using an inline phase contrast tomography system. Slice images were reconstructed using a filtered back‐projection (FBP) algorithm. Standardized axial and coronal planes were adjusted with a multi‐planar reconstruction method. Some three‐dimensional (3D) objects were reconstructed by surface rendering. The characteristic features of microstructures, including otoconia masses of the saccular and utricular maculae, superior and inferior macula cribrosae, single canal, modiolus, and osseous spiral lamina, were described in detail. Spatial positions and relationships of the vestibular structures were exhibited in 3D views. This study investigated mouse inner ear anatomy and provided a standardized presentation of microstructures. In particular, otoconia masses were visualized in their natural status without contrast for the first time. The comprehensive anatomy atlas presented in this study provides an excellent reference for morphology studies of the inner ear.     

Three-dimensional reconstruction of the guinea pig inner ear, comparison of OPFOS and light microscopy, applications of 3D reconstruction

Three-dimensional (3D) reconstruction of anatomical structures can give additional insight into the morphology and function of these structures. We compare 3D reconstructions of the guinea pig inner ear, using light microscopy and orthogonal plane fluorescence optical sectioning microscopy. Applications of 3D reconstruction of the inner ear are further explored. For each method two bullas were prepared for 3D reconstruction. Both methods are explained. In general, the 3D reconstructions using orthogonal plane fluorescence optical sectioning microscopy are superior to light microscopy. The exact spiral shape of the cochlea could be reconstructed using orthogonal plane fluorescence optical sectioning microscopy and the length of the basilar membrane measured. When a resolution of 20 μm is sufficient, orthogonal plane fluorescence optical sectioning microscopy is a superior technique for 3D reconstruction of inner ear structures in animals.     

结构参数对压裂双弯头冲蚀及流致变形的影响*

双弯头管汇是水力压裂地面高压管汇系统中的关键部件,由于高压大排量携砂压裂液在其中多次强制转向,双弯头管汇长期遭受着严重的冲蚀磨损和流致变形。为改善管件冲蚀磨损状态,从管汇结构参数的角度研究其对冲蚀率的影响。采用计算流体力学(CFD)数值模拟,结合离散相模型(DPM)和流固耦合(FSI)方法,对双弯头结构管汇在工况条件下的流致冲蚀和变形情况进行综合分析,研究双弯头结构参数,如连接直管长度、管道内径及弯头间连接角度对冲蚀和变形的影响。结果表明:随着连接直管长度增加,冲蚀率先减小后变化不大,而结构变形程度逐渐增大,综合考虑冲蚀磨损和结构变形,双弯头之间的连接直管长度宜设计为管道外径的4倍;大口径管道的冲蚀磨损程度更低,但会带来更大的变形,因此双弯头管汇的管内径不宜过大或过小;当2个弯头间的连接角度为0°时,冲蚀和变形程度达到最小。     

血液流动性的计算机可视化测定及其技术应用

简要描述了日本MCFAN研究所生产的血液流动性可视化检测仪的测定原理、实验方法和临床应用。血液流动性的可视化测定仪（以HR300型为例）将进样系统、计算机处理系统、显微摄像等一体化（Micro Channel Array Flow Analyzer,MCFAN）,使操作繁琐的血液流变性观察检测变得简便易行,并通过液晶显示器可观察到血流的状态,具有直观形象的特点。广泛用于预防医学、药物研究、疾病诊断和健康教育等领域,并为大众健康咨询提供了直接支持,本文比较全面的介绍了血液流动性的检测方法及其临床应用。     

陶瓷喷砂嘴结构参数对冲蚀磨损的影响

根据喷砂工作原理和喷枪结构特征建立了引射段的自由射流模型。研究了喷砂嘴结构参数(粗糙度、内径、长度)变化时,喷砂嘴和喷枪内的气固两相流场性质和变化过程。并结合陶瓷材料的冲蚀磨损机理,分析了流场对磨料运动和冲蚀磨损的影响。结果表明,合理选择喷砂嘴的结构参数对减轻喷砂嘴的冲蚀磨损,提高其使用寿命具有重要作用。该结论对进行喷砂嘴的耐磨结构设计具有重要的指导意义。     

Evaluation of Nanoscale Friction Depth Distribution in ZDDP and MoDTC Tribochemical Reacted Films Using a Nanoscratch Method

The distributions of local friction coefficients relative to the depth and near the surface of MoDTC/ZDDP and ZDDP tribofilms were successfully evaluated by using a nanoscratch method combined with in situ AFM observation. It was found that both tribofilms were friction-functionally graded materials. The friction coefficients decreased from 0.35 to 0.16 with a decrease in the scratch depth from 60 to 10 nm. It was observed that the MoDTC/ZDDP and ZDDP tribofilms possessed different shear strength levels near the surface as evidenced by the different valley-shaped friction coefficient distributions they exhibited for scratch depths ranging from 2 to 10 nm. Based on our recent nanomechanical measurements, this observation indicated that both tribofilms possessed an ultra-low friction inner skin layer at a depth of about 10 nm below the surface. Most importantly, the inner skin layer of the MoDTC/ZDDP tribofilm possessed a lower friction coefficient than that of the ZDDP tribofilm (0.084 versus 0.104) and was thinner (about 3.2 nm versus 6.4 nm). These results thus revealed that the reduction in friction attributed to the MoDTC additive originates from the different friction behavior of the inner skin layers of the MoDTC/ZDDP and ZDDP tribofilms. These nanoscratch results agree with the findings of our recent work on detecting differences in mechanical properties between these tribofilms by nanoindentation measurements.