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.     

动结式的宾语前置状况的分析

配价语法引入汉语后,动结式的配价研究也逐渐深入。根据动结式所带论元,可以分为一价动结式、二价动结式以及三价动结式。近些年随着动结式配价研究的发展,动结式的配位方式也开始受到关注。文章分析动结式的带宾情况及宾语前置的条件,在讨论二价、三价动结式后带宾语通例的基础上,得出动结式在三种情况下宾语往往前置的结论。     

Association between non-alcoholic fatty liver disease and arterial stiffness in the non-obese,non-hypertensive,and non-diabetic young and middle-aged Chinese population

Background and objective: Non-alcoholic fatty liver disease (NAFLD) is associated with arterial stiffness in the general population. Age, obesity, hypertension, and diabetics are risk factors for arterial stiffness. In this study, we aimed to investigate the association between NAFLD and arterial stiffness as measured by brachial-ankle pulse wave velocity (baPWV) in the non-obese, non-hypertensive, and non-diabetic young and middle-aged Chinese population. Methods: A cross-sectional study with 1296 non-obese, non-hypertensive, and non-diabetic young and middle-aged (20–65 years) subjects undergoing routine medical check-ups in the International Health Care Center of the Second Affiliated Hospital of School of Medicine of Zhejiang University was carried out. Fatty liver was diagnosed by ultrasonography, and baPWV was measured using an automatic waveform analyzer. The subjects were classified into two groups according to the presence of NAFLD, and divided into a further two groups according to their baPWV. Results: The overall incidence of NAFLD was 19.0%, and NAFLD patients had a significantly higher level of baPWV than the controls ((1321±158) cm/s vs. (1244±154) cm/s; P<0.001). The incidence of NAFLD was clearly higher in the increased baPWV group than in the normal baPWV group (29.3% vs. 16.9%; P<0.001), and the incidence increased in line with the increase of baPWV quartiles in the normal range as well as with the severity of arterial stiffness (both P for trend <0.001). Multiple linear logistic regression analysis showed that the presence of NAFLD was positively and independently associated with baPWV. Conclusions: Our results suggest that the presence of NAFLD is associated with arterial stiffness as measured by baPWV in the non-obese, non-hypertensive, and non-diabetic young and middle-aged Chinese population.     

用药和细胞的活性材料(英文)

已经制备出一种新颖.的肝素结合剂,这是一种可以被生物降解的多乳酸(PLA) 肝素聚合体.作为生物活性制剂的生物组织,如牛的心外膜,由细胞组成的或者无细胞组成的(BP/ABP)间质,是在谷氨醛(GA)交叉连接后用直接复制L 精氨酸(Arg)或肝素(Hep)而进行化学修改而成.PLA 肝素表面显示出亲水性的改善,降低了血浆蛋白质吸收性,减少了血小板的粘连性,提高了和血液的相容性以及与细胞的相容性.由此可建议,PLA 肝素聚合体对于与血液相接触的材料是有用的,特别是可以用于心血管组织的支架材料中.在由化学修改的细胞组成的间质中,经过Arg或Hep处理过的间质,它们的热力学性质和力学性质都要比原始的和经过GA处理的细胞组成间质的性能好.钙化实验中显示:在Arg和Hep处理过的间质上的钙沉积作用要少,细胞增殖的范围要比经过GA处理的材料高.本文结果证明用化学修改的无细胞间质或由细胞组成的间质作为新型生物材料在心血管及其组织的工程应用有效.     

Vocabulary does not complicate the simple view of reading

Gough and Tunmer’s (1986) simple view of reading (SVR) proposed that reading comprehension (RC) is a function of language comprehension (LC) and word recognition/decoding. Braze et al. (2007) presented data suggesting an extension of the SVR in which knowledge of vocabulary (V) affected RC over and above the effects of LC. Tunmer and Chapman (2012) found a similar independent contribution of V to RC when the data were analyzed by hierarchical regression. However, additional analysis by factor analysis and structural equation modeling indicated that the effect of V on RC was, in fact, completely captured by LC itself and there was no need to posit a separate direct effect of V on RC. In the present study, we present new data from young adults with sub-optimal reading skill (N = 286). Latent variable and regression analyses support Gough and Tunmer’s original proposal and the conclusions of Tunmer and Chapman that V can be considered a component of LC and not an independent contributor to RC.     

尾套法与颈动脉法测量大鼠血压的相关性研究

对比研究无创尾套法与有创颈总动脉法测量健康大鼠血压的相关性。依次使用尾套法和颈总动脉法测量不同性别和年龄组的健康大鼠收缩压。各组无创血压值均高于有创血压值(P<0.001),两者呈显著直线相关(P<0.01)。清醒动物实验中使用无创血压可以有效,便捷地获取血压参数,减少动物创伤应激。     

一阶RC积分电路时间常数的测量方法研究

文章给出了一种测量RC积分电路时间常数的实验方法。利用信号源幅值与电容两端电压之间的比例关系,解决了不能在RC积分电路响应波形图中利用常规方法测量时间常数的问题。     

Design,Fabrication, and Modeling of CMOS-Compatible Double Photodiode

A double photodiode (PD) constructed by p⁺/N-well junction and N-well/p-sub junction was designed and fabricated in a UMC 0.18-μm CMOS process. Based on the device structure and mechanism of double PD, a novel small-signal equivalent circuit model considering the carrier transit effect and the parasitic RC time constant was presented. By this model with complete electronic components, the double PD can be incorporated in a commercial circuit simulator. The component values were extracted by fitting the measured S-parameters using simulated annealing algorithm, and a good agreement between the measurement and the simulation results was achieved.     

自然语义元语言理论:内容、发展和面临的挑战

自然语义元语言理论是Anna Wierzbicka及其同事发展的一种语义学理论,要旨是确定存在于自然语言之下的语义原子,即基本语义。基本语义独立于任何语言和文化,在所有语言中都可找到对应形式。不同语言使用者都可理解基本语义,运用它们可进行有效交流。使用基本语义解释不同语言的词义,可避免文化差异导致的偏差。这一理论在语言学和认知科学界产生了较大反响。本文综述了这一理论的内容和近期发展,并指出这一理论面临的挑战。     

自动泊车小车转弯参数及特征环境参数的确定

讨论了基于模型小车的车辆自动泊车系统的基本参数计算.通过小车最小转弯半径,转弯环道最小宽度的计算,并结合自动泊车策略所需要考虑的综合因素,确定了自动泊车小车转弯参数及特征环境参数.针对实际车辆与模型小车在参数上的区别,以及测距方案的实际情况,对计算结果进行了简单的分析.     

Students’ Ideas and Radical Constructivism

In this article, I study, from the point of view of the analytic philosophy of mind, the compatibility of students’ ideas studies (SIS) with radical constructivism (RC). I demonstrate that RC is based on a psychology of narrow mental states; that is, the idea that the mental content of an individual can be fully characterised without any reference external to her or him. I show that this fact imposes some severe restrictions to SIS to be incorporated into RC. In particular, I argue that only qualitative studies can comply with the requirement of narrowness. Nevertheless, I propose that quantitative works can be employed as sources of types in order to study token actual students. I use this type-token dichotomy to put forward an outline of a theory of the relation between school contents and mental contents. In this view, token mental contents regarding a given topic can be defined, and probed, only by resorting to typical school contents.     

RC电路充放电特性的计算机辅助分析

应用Multisim软件对RC电路的充放电波形进行了分析,并讨论了电路参数C的变化对输出信号的影响．结果证实:在RC电路中,合上开关的瞬间,电路中有充电电流流过;输出波形随输入脉冲的振幅、时间常数的不同而变化．     

用于电穿孔效应实验的亚微秒脉冲电源研制

针对肿瘤细胞电穿孔效应的实验需求,用幅值可调的高压直流电源为电容充电,具有一定时间延时的2路TTL信号分别控制串联的2个IGBT模块的通与断,以便从电容放电曲线中截取适当脉宽电脉冲的方法,研制了一台输出脉冲电压0.5～3.5kV连续可调、脉宽300～800ns准连续可调、重频1～400Hz连续可调的亚微秒脉冲电源。实验测试结果表明,该脉冲电源性能稳定可靠,可用于恶性肿瘤电穿孔实验。     

从PPG模式看B2C的崛起

“B2C”、“网上直销”这些曾一度沉寂的名词在2007年再度被人们提起,在B2C模式的背后涌现了一批象PPG一样的践行者。而论2007年国内服装行业的风云企业,PPG则可以被称为服装业的一匹黑马,PPG的成功无疑将成为业界讨论的焦点。本文从PPG的商业模式着手,透过PPG等“轻资产”企业的竞争力分析说明B2C这一曾经风光无限的电子商务模式正重新焕发新的光彩。     

怀化市60-69岁城乡老年人身体机能对比研究

运用文献综述法、测试法和数理统计法,对怀化市鹤城区、芷江县、中方县、洪江县、通道县60-69岁老年人的安静脉搏、收缩压、舒张压、肺活量进行测试,并与同龄乡村老年人进行身体机能对比．结果表明：1）怀化市60—69岁城乡男性老年人的呼吸系统机能优于同年龄组的城乡女性老年人,且下降速度也较同年龄组的女性老年人缓慢;2）怀化市...     

Characterization of human genetics courses for nonbiology majors in U.S. colleges and universities

We characterized college human genetics courses for nonscience majors (NSM) by 1) determining the number of U.S. institutions offering courses and the number of students taking them; and 2) surveying course instructors on course demographics, content, materials, and pedagogies. Between 2002 and 2004, an estimated 480 institutions of higher education (15.2%) offered a course: 8.4% of 1667 associate colleges, 16.1% of baccalaureate institutions, 25.3% of master's institutions, and 32.9% of doctoral institutions. This indicates a need to increase access to genetics education in 2-yr colleges. Based on instructor responses, approximately 32,000–37,000 students annually complete an NSM human genetics course out of approximately 1.9 million students earning a college degree each year (2.0%). Regarding course content, instructors consistently rated many concepts significantly higher in importance than the emphasis placed on those concepts in their courses. Although time could be a factor, instructors need guidance in the integration of the various concepts into their courses. Considering only 30.2% of the instructors were reportedly trained in genetics (another 25.4% in molecular and cellular biology) and the small fraction of students completing NSM human genetics courses, these results demonstrate the need for increasing the availability of these courses in undergraduate institutions of higher education, and particularly at 2-yr colleges.     

Wavelet-based deconvolution of ultrasonic signals in nondestructive evaluation

INTRODUCTION Deconvolution of ultrasonic signals is defined as the solution of the inverse problem of convolving an input signal, known as the system function h(n), with a medium reflectivity function x(n) and can be rep- resented by y(n)=h(n)*x(n) η(n), (1) where y(n) is the measured signal, * denotes the convolution operation and η(n) is the additive noise. Recovering x(n) from the observation y(n) leads to improving the appearance and the axial resolution of the RF-signals by removin…     

Flat-top and low-dispersion optical interleavers based on nested prism pair structure

A novel flat-top and low-dispersion optical interleaver using ring cavities (RCs) in a Mach-Zehnder interferometer (MZI) is proposed. It is composed of eight mirrors and two nested prism pairs. Each prism and the two mirrors behave as a RC. Phase shift of RC is a periodic function of the frequency of the input light which acts as a phase dispersive mirror. The two phase shifts needed to achieve a flat-top spectral passband are provided by Fresnel reffectivities at the prism-air interface of the two RCs. The...     

双音述宾结果补语“动结式”初探——兼论韵律运作、词语整合与动结式的生成

汉语动结式内部是非同质性的,情况非常复杂。本文讨论的是由双音述宾形式充当结果补语构成的动结式(V+VN),这种格式具有独特的句法语义特征,是韵律运作、词语整合的结果,值得进一步探索。本文主要讨论两个问题:第一,V+VN动结式的句法特征;第二,V+VN动结式的形成机制。     

Shear strengthening of pre-damaged reinforced concrete beams with carbon fiber reinforced polymer sheet strips

This paper presents the results of an experimental investigation on the response of pre-damaged reinforced concrete (RC) beam strengthened in shear using applied-epoxy unidirectional carbon fiber reinforced polymer (CFRP) sheet. The reasearch included four test rectangular simply supported RC beams in shear capacity. One is the control beam, two RC beams are damaged to a predetermined degree from ultimate shear capacity of the control beam, and the last beam is left without pre-damaged and then strengthened with using externally bonded carbon fiber reinforced polymer to upgrade their shear capacity. We focused on the damage degree to beams during strengthening, therefore, only the beams with side- bonded CFRPs strips and horizontal anchored strips were used. The results show the feasibility of using CFRPs to restore or increase the load-carrying capacity in the shear of damaged RC beams. The failure mode of all the CFRP-strengthened beams is debonding of CFRP vertical strips. Two prediction available models in ACI-440 and fib European code were compared with the experimental results.