Nicotinamide adenine dinucleotide (NADH) is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation (OXPHOS). NADH is autofluorescent, and its fluorescence lifetime can be used to infer metabolic dynamics in living cells. Fiber-coupled time-correlated single photon counting (TCSPC) equipped with an implantable needle probe can be used to measure NADH lifetime in vivo, enabling investigation of changing metabolic demand during muscle contraction or tissue regeneration. This study illustrates a proof of concept for point-based, minimally-invasive NADH fluorescence lifetime measurement in vivo. Volumetric muscle loss (VML) injuries were created in the left tibialis anterior (TA) muscle of male Sprague Dawley rats. NADH lifetime measurements were collected before, during, and after a 30s tetanic contraction in the injured and uninjured TA muscles, which was subsequently fit to a biexponential decay model to yield a metric of NADH utilization (cytoplasmic vs protein-bound NADH, the A1τ1/A2τ2 ratio). On average, this ratio was higher during and after contraction in uninjured muscle compared to muscle at rest, suggesting higher levels of free NADH in contracting and recovering muscle, indicating increased rates of glycolysis. In injured muscle, this ratio was higher than uninjured muscle overall but decreased over time, which is consistent with current knowledge of inflammatory response to injury, suggesting tissue regeneration has occurred. These data suggest that fiber-coupled TCSPC has the potential to measure changes in NADH binding in vivo in a minimally invasive manner that requires further investigation.

研究了学龄前儿童户外运动设计对其视力发展情况的影响。选取上海市中心城区一所示范性幼儿园, 通过问卷调查幼儿用眼习惯和父母近视情况, 用单因素分析方法分析影响幼儿视力的因素, 得知父母近视是导致幼儿阶段视力问题的主要原因(P＜0.001); 基于眼肌调节机制设计有助于改善幼儿视力的户外运动游戏, 并对不同年龄段幼儿分层实施, 通过Snellen视力表检查和电脑验光仪屈光数据综合分析, 发现运动游戏实施后两组幼儿视力情况有明显差异(P=0.012), 对于有潜在视力风险的幼儿, 尤其是中大班幼儿效果最明显。该类运动游戏具有积极的作用, 适宜在幼儿园和家庭中开展和普及。

Based on the biological characteristics of tulip, the low driving voltage and fast response of ionic polymer metal composite (IPMC), we analyzed the fabrication, morphology and performance of the platinum IPMC (Pt-IPMC) and selected the right IPMC for driving bionic tulip. The preparation and performance of IPMC was analyzed first in this paper such as blocking force, output displacement and bending angle of IPMC under the different directed current voltage (DC). The optimal IPMC sample size and driving voltage were selected based on tulip blooming angles and the strain energy density of IPMC, which completed the blooming process of bionic tulip. The feasibility of IPMC used in driving bionic field was fully proved in this paper, which laid a foundation for the application of IPMC in driving biomimetic biological robots.

目的：观察分析对经皮激光气化减压术(percutaneous lasers disk deoom pression,PLDD)治疗腰椎间盘突出症(lumbar disc herniation, LDH)患者术后表面肌电图监测数据变化情况, 探究躯干肌电活动规律与PLDD疗效的相关性。方法：对2015年3月至2016年4月对36例在甘肃省中医院接受PLDD治疗的LDH患者进行术中、术后表面肌电(surface electromygraphy, sEMG)及表面肌电生物反馈(surfaceelectromygraphic biofeedback, sEMGBF)监测。受试患者分别采用长收缩状态、运动状态、静态体位状态下进行椎旁肌群sEMG监测, 测试椎旁肌肉群患侧与健侧的中位频率斜率(MF slope, MFs)、曲伸直比(FER)以及平均肌电图波幅, 整理测试数据进行统计分析。结果：PLDD术后1月、3月及6月时, 术后患侧MFs的衰减降低, 与治疗前比较差异显著(P<0.05), 健侧MFs的衰减无显著改变；PLDD术后平均EMG波幅健侧无显著改变, 患侧波幅有增高趋势, 但差异无显著性。患侧FER=0.46±0.13, 与治疗前FER=0.89±0.19；比较差异具有显著性(P<0.05), 健侧FER的衰减无显著改变。结论：经皮激光汽化减压术治疗腰椎间盘突出症可明显改善椎旁肌肉疲劳、活动失调、平衡失调等病理性状态, 有效恢复椎旁肌肉的强度、平衡性和协调性；LDH治疗后的sEMG监测临床疗效的评价和疾病预后的判断具有积极的临床意义。Regularity in Patients with Lumbar Disc Herniation

The current work is focused on the study of optical clearing of skeletal muscles under local compression. The experiments were performed on in vitro bovine skeletal muscle. The time dependence of optical clearing was studied by monitoring the luminescence intensity of NaYF4: Er,Yb upconverting particles located under tissue layers. This study shows the possibility to use upconverting nanoparticles (UCNPs) both for studying the dynamics of the optical clearing of biological tissue under compression and to detect moments of cell wall damage under excessive pressure. The advantage of using UCNPs is the presence of several bands in their luminescence spectra, located both at close wavelengths and far apart.

肌肉计算机接口(MCI)系统是虚拟现实、人机交互研究的热点之一, 其核心问题是EMG肌电信号分类, 因而MCI系统可以与深度学习方法有效结合。表面EMG信号分为高密度瞬时信号与稀疏多通道信号, 前者类似于图像, 可以采用CNN网络处理; 本文应用RNN网络对后者进行研究, 并利用MYO臂环实现了相应MCI系统。稀疏多通道EMG信号是不定长时间序列信号, 前后时间相关性高, 采用RNN网络进行分类。通过对原始信号进行时域、时频域、频域特征拓展, 获得原始信号的多流特征序列, 并提出两类组合RNN网络架构处理相应多流信号。用户依赖时算法准确率达90.78%, 非用户依赖的人群测试中手势识别准确率达78.01%, 实时动作识别准确率达82.09%, 算法能在61.7毫秒内识别手势动作。本文所提出的组合RNN网络方法可以有效区分基于EMG信号的不同动作, 且所设计的MCI系统用户泛化性与工作实时性表现好。

偏振成像可用于表征各向异性肌肉组织,但是常规偏振成像方法只能给出定性的结构形态,无法对肌肉发育过程进行定量的比较。构建了一套定量偏振成像系统,采用两个互相垂直的偏振片同步旋转得到一系列图像,经过图像处理获取斑马鱼每个肌节定量的相位延迟量。该定量偏振图像与光源亮度、曝光时间等无关,可以用来比较不同时间拍摄的斑马鱼肌肉形态和分布。研究发现野生型和肌肉受损型斑马鱼肌肉生长变化过程不同。

Noninvasive techniques, surface electromyography (sEMG) in particular, are being increasingly employed for assessing muscle activity. In these studies, local oxygen consumption and muscle metabolism are of great interest. Measurements can be performed noninvasively using optics-based methods such as near-infrared spectroscopy (NIRS). By combining energy consumption data provided by NIRS with muscle level activation data from sEMG, we may gain an insight into the metabolic and functional characteristics of muscle tissue. However, muscle motion may induce artifacts into EMG and NIRS. Thus, the inclusion of simultaneous motion measurements using accelerometers (ACMs) enhances possibilities to perceive the effects of motion on NIRS and EMG signals. This paper reviews the current state of noninvasive EMG and NIRS-based methods used to study muscle function. In addition, we built a combined sEMG/NIRS/ACM sensor to perform simultaneous measurements for static and dynamic exercises of a biceps brachii muscle. Further, we discuss the effect of muscle motion in response of NIRS and EMG when measured noninvasively. Based on our preliminary studies, both NIRS and EMG supply speciˉc information on muscle activation, but their signal responses also showed similarities with acceleration signals which, in this case, were supposed to be solely sensitive to motions.

由于人体组织结构的复杂性和个体差异性, 采用光谱分析技术实现组织内部信息的检测方法中, 仍存在着检测位置不明确的问题。 采用多位置空间分辨漫反射光谱法对脂肪肌肉组织中内部信息的最佳探测位置进行了研究。 由于目标组织为肌肉组织, 为了消除由于不同人体皮下脂肪层厚度的差异以及目标层中多次后向散射光对测量结果引起的较大误差, 并根据光在复杂生物组织中的传输模型, 通过增加约束条件——两条理想的“香蕉型”路径—来定义有效光子比SNR, 并以SNR作为评价最佳探测位置SDSbest的标准, 对优化后的Monte Carlo仿真结果进行统计分析, 分别研究了脂肪层厚度hf、 脂肪层吸收系数μaf和肌肉层吸收系数μam与光源探测器间距SDS之间的关系, 并以hf为自变量与SDSbest建立线性回归模型。 研究表明, (1)当0脂肪肌肉组织 内部组织信息 最佳检测位置 空间漫反射光谱 Monte Carlo模拟 Fat-muscle tissue Inner information of tissue Best Source-detector Distance Spatially diffuse reflectance spectra Monte Carlo simulation 

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光谱学与光谱分析

2016, 36(10): 3434