Effect of local thermal sensation on whole-body thermal sensation under stable non-uniform environment

To reveal the principles of human thermal responses and find out the effects of body parts on whole-body thermal sensation,through a subjective survey,experimental investigations on human responses are carried out when a single body part is thermally stimulated.Cooling airflow is sent to seven body parts,respectively.Totally 94 samples are tested.To eliminate the obvious multicollinearity of thermal sensation among different body parts,the principal component regression approach is adopted to obtain the principal components for the body parts under different experimental conditions.Through regression and analysis of principal components,the weighting factors of the seven body parts are obtained.A predictive model on whole-body thermal sensation is obtained based on the weighting factors.The results show that the different characteristics of trunk and limbs are clearly seen.The weighting factors of local thermal sensation are integrated values,and there is little difference among values of different body parts.

Whole-body heat exposure induces membrane changes in spermatozoa from the cauda epididymidis of laboratory mice

This study was carried out to determine if exposure to hot environmental temperatures had a direct, detrimental effect on sperm quality. For this the effect of whole-body heat exposure on epididymal spermatozoa of laboratory mice was investigated. C57BL/6 mice （n = 7） were housed in a microclimate chamber at 37℃-38℃ for 8 h per day for three consecutive days, while control mice （n = 7） were kept at 23℃-24℃. Cauda epididymal spermatozoa were obtained 16 h after the last heat treatment. The results showed that sperm numbers were similar in the two groups （P = 0.23）, but after heat treatment, a significant reduction in the percentage of motile sperm was present （P 〈 0.0001）. Membrane changes of the spermatozoa were investigated by staining with phycoerythrin （PE）- conjugated Annexin V, which detects exteriorization of phosphotidylserine from the inner to the outer leaflet of the sperm plasma membrane, and 7-aminoactinomycin D （7-AAD）, which binds to the sperm nucleus when the plasma membrane is damaged. The percentage of spermatozoa showing positive staining with Annexin V-PE or 7-AAD or both, was significantly higher （P 〈 0.05） in heat-exposed mice compared with controls. These results show that whole-body heat exposure to 37℃-38℃ induces membrane changes in the epididymal spermatozoa of mice, which may lead to apoptosis.

Accuracy and Consistency of Respiratory Inductive Plethysmography for Overnight Tidal Volume Measurement

To validate the accuracy and consistency of respiratory inductive plethysmography (RIP) in measuring tidal volume after an overnight sleep, tidal volumes of 18 patients with suspected sleep disordered breathing and 8 normal volunteers were measured simultaneously with RIP (V TRIP ) and with an ultrasonic airflow meter (V TUFM ) before and after an unstrained overnight sleep on supine and lateral decubitus. The bias of the V TRIP was expressed as (V TRIP V TUFM )/ V TUFM ·100 %, limits of agreement between V TRIP and V TUFM was measured by averaged bias ±2 s . Results showed that in normal subjects, the bias of RIP before and after overnight sleep was precise and consistent in both supine (0.7 % and -1.6 %) and lateral decubitus (3.7 % and -0.56 %). In these patients, the bias of RIP before and after sleep in supine also remained small (1.9 % and 1.7 %), but it became larger in lateral decubitus (24.5 % and 20.4 %) and 11.5 % exceeded the limits of agreement observed in the evening. The patients′ body mass indices (BMI) were higher than those of normal subjects (median 34.2 vs. 27.8 kg/m 2). Pooled data showed that the bias of V TRIP in the morning on lateral decubitus but not on supine was correlated to BMI (Spearman R=0.32, n =52, P =0.02). Thus, we were led to conclude that the accuracy of V TRIP overnight was precise and consistent in normal subjects, but the deviation of V TRIP measured on lateral decubitus in patients especially in those with excessive obesity was greater, thus, the method should not be used for quantitative determination.

Incorporation of circulating tumor cells and whole-body metabolic tumor volume of 18F-FDG PET/CT improves prediction of outcome inⅢB stage small-cell lung cancer

Objective: We investigated the correlation between the number of circulating tumor cells(CTCs) and wholebody metabolic tumor volume(WBMTV) measured by 18 F-fluorodeoxyglucose(FDG) positron emission tomography/computed tomography(PET/CT).The aim was to evaluate the value of the incorporation of CTC number and WBMTV in the prognostic prediction of stage III small-cell lung cancer(SCLC).Methods: One hundred and twenty-nine patients were enrolled in this study.All patients were treated with four cycles of a platinum-based regimen and concurrent chest irradiation,followed by prophylactic cranial irradiation.Blood samples for CTC analysis were obtained from 112 patients before the initiation of chemotherapy(as a baseline),after cycle 1 and after cycle 4.CTCs were measured using the CELLSEARCH? system.The patients underwent pretreatment FDG PET/CT WBMTV,which included all malignant lesions.The Spearman rank test was used to determine the correlation among CTC counts,WBMTV and disease stage.Overall survival(OS) and progression-free survival(PFS) curves were produced using the Kaplan-Meier method,and survival differences between groups were assessed by the log-rank test.Results: The number of CTCs at baseline did not correlate with WBMTV before the initiation of therapy(P=0.241).The number of CTCs at baseline and the WBMTV before the initiation of therapy were independent relevant factors for PFS and OS.The subgroup analysis(Group A: CTC count >19.5 and a WBMTV >266.5cm~3;Group B: CTC count >19.5 and a WBMTV ≤266.5cm~3; Group C: CTC count ≤19.5 and a WBMTV >266.5cm~3;Group D: CTC count ≤19.5 and a WBMTV ≤266.5cm~3) showed that the differences were statistically significant in the median PFS(Group A vs.D,P<0.001; Group B vs.D,P=0.018; Group C vs.D,P=0.029) and in the median OS(Group A vs.D,P<0.001; Group B vs.D,P=0.012).Conclusions: CTC number and WBMTV are related to progression and death in patients with SCLC.The incorporation of CTC number and WBMTV scans can provide a detailed prognostic prediction for SCLC.

Automatic detection of respiratory rate from electrocardiogram,respiration induced plethysmography and 3D acceleration signals

Respiratory monitoring is increasingly used in clinical and healthcare practices to diagnose chronic cardio-pulmonary functional diseases during various routine activities.Wearable medical devices have realized the possibilities of ubiquitous respiratory monitoring,however,relatively little attention is paid to accuracy and reliability.In previous study,a wearable respiration biofeedback system was designed.In this work,three kinds of signals were mixed to extract respiratory rate,i.e.,respiration inductive plethysmography(RIP),3D-acceleration and ECG.In-situ experiments with twelve subjects indicate that the method significantly improves the accuracy and reliability over a dynamic range of respiration rate.It is possible to derive respiration rate from three signals within mean absolute percentage error 4.37%of a reference gold standard.Similarly studies derive respiratory rate from single-lead ECG within mean absolute percentage error 17%of a reference gold standard.

Image Quality Stability of Whole-body Diffusion Weighted Imaging

Objective To assess the reproducibility of whole-body diffusion weighted imaging(WB-DWI) technique in healthy volunteers under normal breathing with background body signal suppression.Methods WB-DWI was performed on 32 healthy volunteers twice within two-week period using short TI inversion-recovery diffusion-weighted echo-planar imaging sequence and built-in body coil.The volunteers were scanned across six stations continuously covering the entire body from the head to the feet under normal breathing.The bone apparent diffusion coefficient(ADC) and exponential ADC(eADC) of regions of interest(ROIs) were measured.We analyzed correlation of the results using paired-t-test to assess the reproducibility of the WB-DWI technique.Results We were successful in collecting and analyzing data of 64 WB-DWI images.There was no significant difference in bone ADC and eADC of 824 ROIs between the paired observers and paired scans(P>0.05).Most of the images from all stations were of diagnostic quality.Conclusion The measurements of bone ADC and eADC have good reproducibility.WB-DWI technique under normal breathing with background body signal suppression is adequate.

Effect of Short-Term Whole-Body Vibration Training on Metabolic Risk Factors, Inflammatory Markers, and Arterial Stiffness

To investigate the effect of aerobic exercise combined with whole-body vibration (WBV) training on metabolic syndrome risk, and inflammatory markers, and to compare its effects on arterial stiffness and several blood parameters related to metabolic syndrome with those of aerobic training alone. Thirty healthy participants were divided into 2 groups matched for age and body mass index (BMI). Fifteen subjects were assigned to the WBV group (WBV + aerobic training) and the other 15 to the control group (aerobic training only). All participants performed a treadmill exercise 3 days/week for 4 weeks, for 50 min after 30 min rest period. Exercise was performed at a heart rate (HR) corresponding to 60% of the HR at each individual’s maximum oxygen uptake (VO2max). Body weight and BMI after training were significantly lower than those before training in the WBV group (P < 0.01). Concerning arterial stiffness, the pulse-wave velocity after training was significantly lower than that before training in the WBV group (1048.7 ± 105.6 vs. 1008.4 ± 101.1 cm/s, P < 0.05). Meanwhile, the VO2max after training was significantly higher than that before training in the WBV group (47.7 ± 12.8 vs. 51.4 ± 14.1 mL·min-1·kg-1, P < 0.01). However, no significant differences were observed in any parameters before and after training in the control group. Our results suggest that aerobic exercise combined with WBV training may be effective in reducing arterial stiffness and improving cardiorespiratory fitness than aerobic training alone.

Development of forearm impedance plethysmography for the minimally invasive monitoring of cardiac pumping function

It is essential to continuously and non-invasively monitor the cardiac pumping function in clinical setting. Thus, the study aimed to explore a regional impedance phethysmographic method to assess the changes in stroke volume. To do this, we developed a plethysmographic device that was capable of delivering a single-frequency current with constant amplitude and of recording electrical impedance signals of biological tissue. The electrical impedance plethy- smographic waveform form the lower arm was measured with the impedance plethysmographic device, and simultaneously the end-systolic and end- diastolic volumes of the left ventricle were obtained with a two-dimension echocardiographic system in fourteen healthy subjects before and immediately after a thirty-second breath-hold maneuver. For the 14 subjects, a linear correlation coefficient of 0.79 (p < 0.001) was obtained between the changes in peak amplitude of the forearm impedance waveform and the changes in stroke volume before and just after the breath-hold test. In addition, the changes in the mean area under the impedance curve and the change in stroke volume were also correlated linearly (r = 0.71, p < 0.005). In summary, the forearm impedance plethysmography may be employed to evaluate the beat-to-beat alteration in cardiac stroke volume, suggesting its potential for long-term monitoring cardiac pumping performance.

MEASUREMENT OF ^(124)Sb IN VIVO WITH WHOLE-BODY COUNTER

The 124Sb in vivo exposed person is measured with whole-body counter. Thesolid point source method is applied to calibrate the counter. The minimum detectable activity of this system for 124Sb is 32 Bq.

PRELIMINARY PROGRAMMED WHOLE-BODY COUNTER

It is capable of giving the initial intakes of radionuclides and the assessment quantities used in radiation protection according to its measured results of radionuclides in vivo. It is accomplished by providing the software of controlling, interface and internal dose estimation programs to the original iron cabin shielding whole-body counter. The preliminary application shows that its data processing is rapid and correct, and can meet the requirement of rapid internal radioactive contamination monitoring and diagnosing in case of lots of internal contamination subjects happened innuclear accident.

Passive Whole-Body Hyperthermia Increases Aerobic Capacity and Cardio-Respiratory Efficiency in Amateur Athletes

Objective: The research was carried out to test the influence of adaptation to passive whole body hyperthermia (PH) on physical capacity and cardio-respiratory efficiency in men-amateur athletes under the testing load of increasing intensity in laboratory thermal-neutral conditions. Twenty-eight amateur athletes (males, mean age 20.2 ± 2.1 y.o., game-based kinds of sports—football, handball, training experience—4 - 7 years) were randomized into two groups: experimental (14 people), who underwent 24 PH procedures, and control (14 people), who underwent 24 light training sessions in interval regime on elliptical gym apparatus. Results: Adaptation to PH was accompanied by moderate increase of aerobic efficiency and cardio-respiratory endurance in amateur athletes under thermally neutral conditions, while interval training in the control group showed no reliable changes in efficiency. Conclusion: A 10-week course of PH procedures leads to the increase of peak oxygen consumption, oxygen consumption at the level of anaerobic threshold, and heart efficiency (enhancement of oxygen pulse values), as well as efficiency of pulmonary ventilation and bronchial conductance, which we consider to be cross effects of adaptation to passive whole-body repetitive hyperthermia.

融合rPPG和人脸三维法向量的非接触情绪感知技术

近年来,基于深度学习的情绪识别技术取得了显著进展。然而,现有方法主要集中在面部图像或视频上,忽略了其他模态信息,导致鲁棒性和稳定性不足。为了解决这一问题,提出了一种融合多模态信息的面部表情识别方法。首先将输入的人脸视频进行远程光电容积脉搏波(Remote Photo plethysmography,rPPG)信号和人脸三维法向量的提取,其次将这两种模态的信息输入其相应的情绪特征提取子网络,提取出对应的情绪特征向量。然后,将这两种模态提取出的情绪特征向量进行融合,生成一个丰富的特征向量,最后将其输入分类器进行情绪分类任务。通过这种多模态信息融合的方式,提高了面部表情识别的准确性和稳定性。对所提方法在不同数据集上进行了验证,实验结果表明,该方法在多样化面部表情识别中的表现优于当前先进的情感识别方法,具有更高的鲁棒性和稳定性。

体积描记法联合血清单核细胞趋化蛋白-1水平预测急性下呼吸道感染患者合并哮喘的效能分析

目的探究体积描记法联合血清单核细胞趋化蛋白-1(MCP-1)对急性下呼吸道感染患者合并哮喘的预测价值。方法回顾性分析2019年6月—2022年12月青海省人民医院收治的188例急性下呼吸道感染患者的病历资料。根据患者住院期间是否并发哮喘分为合并组(48例)和非合并组(140例)。收集并整理所有受试者的人口学资料和实验室检测指标(体积描记法相关参数:肺总量、残气量、残气率,血清MCP-1水平)。比较两组患者临床资料的差异,分析肺总量、残气量与功能残气量(FRC)、MCP-1的相关性,分析影响急性下呼吸道感染患者并发哮喘的相关因素,以及FRC、MCP-1对急性下呼吸道感染患者并发哮喘的预测价值。结果合并组FRC、肺总量、残气量、残气率、MCP-1水平均高于非合并组(P<0.05)。FRC与肺总量、残气量水平均呈正相关(r=0.681和0.671,均P=0.001);MCP-1与肺总量、残气量水平均呈正相关(r=0.669和0.654,均P=0.001)。多因素逐步Logistic回归分析结果显示:FRC[O^R=2.450(95%CI:1.239,4.840)]、MCP-1[O^R=2.995(95%CI:1.516,5.918)]是急性下呼吸道感染患者并发哮喘的危险因素(P<0.05)。受试者工作特征曲线结果分析显示,FRC、MCP-1及联合预测急性下呼吸道感染患者并发哮喘的敏感性分别为72.92%(95%CI:0.579,0.842)、83.33%(95%CI:0.692,0.920)、79.17%(95%CI:0.645,0.890),特异性分别为81.43%(95%CI:0.737,0.873)、70.71%(95%CI:0.623,0.779)、81.43%(95%CI:0.737,0.873)。结论体积描记法和血清MCP-1水平可用于评估急性下呼吸道感染患者肺功能,且血清MCP-1与体积描记法检测的FRC对急性下呼吸道感染患者并发哮喘的预测效能良好。

基于人脸视频的非接触式心率测量系统研究

心率作为一项重要的生理特征信息,在医疗诊断方面有着不可替代的作用。非接触式心率检测无须与测试者直接接触即可测量出心率,避免了传统心率测量时测试者长时间接触仪器造成的不适,且成本更低,便携性更好。文章提出一种结合ICA和小波变换的算法,对摄像头输入的人脸视频依次进行颜色空间转换、降噪、时频域变换等操作,并搭建了一个基于人脸视频的心率测算系统,针对不同指标设计了多个实验。实验结果表明,系统能够快速实时检测人体心率数据,实现非接触式心率检测,满足心率检测需求。

光照变化下的非接触式血氧饱和度检测方法研究

目的:基于成像式光电容积描记(imaging photo plethysmography,IPPG)技术,提出一种在不同光照条件下依然拥有较高准确率的非接触式血氧饱和度检测方法。方法:首先,通过摄像头采集人脸感兴趣区域的图像;其次,使用自适应伽马校正和欧拉视频放大算法对图像进行预处理;再次,将视频信号转化为数字信号,提取IPPG信号,并使用经验小波变换进行滤波去噪;最后,利用二次函数拟合得到血氧饱和度公式,从而计算出血氧饱和度。结果:相较于其他文献算法,该方法具有更强的抗光照变化干扰能力,在不同光照条件下的平均误差均不超过1.5%,最大误差在2%左右,且与指夹式血氧仪的检测结果具有较好的一致性。结论:该方法在不同光照条件下测量血氧饱和度均具有较高的准确率,能够达到实际测量的要求。

针刺风池穴对脑血流的影响

应用经颅多普勒超声对97例患者进行针刺风池穴前后椎基底动脉血流速度观测,结果表明,治疗组高流速型与低流速型针刺前后血流速度比较均有显著变化(P<0.001),治疗组与对照组两样本针刺后比较有显著差别(P<0.001)。

容积型指脉波图监测及评价体外反搏效果的对照研究

对２０ 名男性健康志愿者采用经桡动脉穿刺置管主动脉根部测压的方法，分别研究不同反搏工作参数对主动脉压力和指脉波的影响。结果反搏时主动脉舒张压随储气罐压力的增加升高（最高可达１６８．５６ ｍ ｍ Ｈｇ）；主动脉舒张波的ｄｐ／ｄｔ值均逐渐上升，但收缩波的ｄｐ／ｄｔ值则呈下降趋势；指脉舒张波起点与主动脉舒张波起点比较平均滞后（１０８．２０±２５．７０） ｍ ｓ，而指脉收缩波起点则平均滞后（９６．６９±３８．７０） ｍ ｓ；指脉波的Ｄ／Ｓ比值与主动脉压力波的Ｄ／Ｓ比值随反搏储气罐压力的增加而同步增加，并由直线回归分析得出动脉Ｄ／Ｓ比值（Ｙ）与指脉Ｄ／Ｓ比值（Ｘ）的回归方程式Ｙ＝ ０．３７６＋ ０．４５７Ｘ。本研究指示体外反搏对动脉压力波的Ｄ／Ｓ比值、舒张压及其ｄｐ／ｄｔ值均有显著影响，指脉波仍然是目前调节反搏工作参数及监测反搏效果的较为安全。

穿戴式、多参数协同监测系统设计

目的为实现低生理、心理负荷下的人体基本生命参数的长时间、动态获取,设计了穿戴式、多参数协同监测系统。方法将生命信息检测技术与可穿戴技术相结合,在弹性背心中嵌入各类传感器,以实现生理信号检测。两条弯曲成"正弦"状导线嵌在弹性背心的胸、腹部作为呼吸运动传感器,用自主产权的呼吸感应体积描记技术提取呼吸运动;用三导联电极提取心电信号,并探索了非粘贴电极的心动信号获取技术;用三维加速度传感器获取体位、体动信息;用负温度系数的热敏电阻测量作业过程中体温变化。结果实现了呼吸、心电、体位、体动、体温等多生理参数的穿戴式、协同监测系统设计。结论穿戴式的生理参数监测系统能够实现低负荷状态下的多生理参数协同获取,为一系列研究工作提供了很好的技术平台。

背心式呼吸感应体积描记系统设计

目的为解决呼吸感应体积描记技术存在的高信噪比与低系统功耗之间的固有矛盾,并消除胸、腹信号耦合干扰,研发一种新型的呼吸感应体积描记技术,并以可穿戴技术的设计理念,设计出可穿戴式呼吸感应体积描记系统。方法采用脉冲式分时激励的方案,在极短的时间内以极高的功率来依次轮流激励各传感线圈;设计了新型的传感线圈结构,将其嵌入背心中,实现了可穿戴式呼吸感应体积描记系统设计。结果获得了高信噪比(高激励功率)、低系统功耗的设计效果,消除了胸、腹信号之间的耦合干扰;背心式的系统设计,外形美观,使用方便,可用于长期动态测量使用。结论该系统性能优良,达到了设计要求,经过标定能够实现通气量无创测量,用于睡眠医学研究能够有效发现睡眠呼吸暂停事件并鉴别类型。

微功耗光电式脉搏测量仪

文中设计测量脉搏的低功耗系统。利用光电传感器抬取指端的光电容积脉搏波信号,进行滤波放大及A/D转换。M68HC908QY4单片机进行控制和数据处理。最后脉搏次数由液晶显示器直观显示。该系统方便快捷,四秒钟就能得到测量结果,并且有功耗低的优点。