冠心病心绞痛患者血尿酸与高敏度C-反应蛋白水平变化及相关性研究

目的 探讨冠心病不稳定型心绞痛患者血清尿酸 (UA)与高敏度C -反应蛋白 (hsCRP)的浓度及两者的相关性。方法 检测 6 0例不稳定型心绞痛患者与 5 0例正常健康人血清UA、hsCRP、甘油三酯 (TG)、胆固醇 (TC)、低密度脂蛋白 (LDL)、空腹血糖 (FBG)水平 ,并进行相关的统计分析。结果 与对照组进行比较 ,发现不稳定型心绞痛患者组UA、hsCRP、LDL水平均明显高于对照组 ,且UA与hsCRP水平呈线性正相反。结论 不稳定型心绞痛患者UA、hsCRP水平是升高的 ,且两者浓度呈线性正相关。

组织工程真皮抗张强度的初步研究

目的采用高敏度小张力膜状生物材料力学性能测定仪检测组织工程真皮的抗张强度。方法分别培养含有不同数量成纤维细胞的胶原凝胶和复方壳多糖真皮替代物,15 d后检测抗张强度。结果组织工程真皮抗张强度随成纤维细胞数量增多而增强(P<0.01),复方壳多糖人工真皮的抗张强度高于胶原凝胶真皮(P<0.01)。结论复方壳多糖真皮替代物具有良好的抗张强度,为临床应用提供稳定机械性能。

Concept and Design of a Novel High-Bandwidth,High-Sensitivity Differential Receiver for Optical Interconnections

A novel high-bandwidth, high-sensitivity differential optical receiver without any additional cost compared to general optical receivers, is proposed for high-speed optical communications and interconnections. High bandwidth and high sensitivity are achieved through a fully differential transimpedance amplifier with balanced input loads and two photodetectors to convert the incident light into a pair of differential photogenerated currents,respectively. In addition,a corresponding 0.35μm standard CMOS optoelectronic integrated receiver with two 60μm × 30μm, 1. 483pF fingered p^＋/n- well/p-substrate photodiodes is also presented. The simulation results demonstrate that it achieves a 1.37GHz bandwidth and a 81.9dBΩ transimpedance gain,supporting data rates up to at least 2Gbit/s. The device consumes a core area of 0. 198mm^2 and the optical sensitivity is at least - 13dBm for a 10^-12 bit error rate under a 2^15 - 1 PRBS input signal.

Partial frequency band match filtering based on high-sensitivity data: method and applications

During seismic data acquisition, a high-sensitivity geophone with a high inherent frequency can increase high frequency energy by suppressing low frequency signals. This could cause a worse response at low frequencies. If the advantages of high-sensitivity data and conventional data are combined, the effective bandwidth will be broadened. Considering this, we propose a partial frequency band match filtering method which can combine the advantages of both high frequency and conventional frequency ranges. By introducing Ricker wavelets with different dominant frequencies and amplitudes, we established a theoretical model which possesses characteristics of both types of seismic data and demonstrates the feasibility of the partial frequency band match filtering method. A test using single shot records shows the effectiveness of this method for widening the effective frequency band.

ACS-1高灵敏度γ射线料位计

一、引言γ射线料位计作为一种基本的同位素仪表,在我国建材、冶金、化工、煤炭等行业已经得到广泛应用。目前我国各行业使用的γ射线料位计,大多数都采用G-Mγ计数管作为探测元件。其主要原因之一是比用碘化钠闪烁体作为探测元件造价低。但是,由于γ计数管探测效率较低,这类料位计所配用的辐射源活度比较大。1987年10月。

氧化锆材料电化学检测汞的性能研究

采用同种合成方法,通过改变在煅烧时通入的气体,获到了氧化锆与氮掺杂氧化锆。以SEM、XRD分析了它们在材料形貌以及物相上的区别。利用电化学工作站对它们进行了CV、EIS、SWASV等电化学性能测试,根据实验得到了在电化学检测汞时的最佳优化条件,随后在该条件下对比研究了它们对汞的电化学灵敏度。实验数据发现氮掺杂后的氧化锆比氧化锆在检测汞上占据了明显的优势,表明氮掺杂能够增强氧化锆的电催化效果,其检测汞的灵敏度达到了1457μA·cm-2·μM-1,且检测限为0.03μM。另外氮掺杂氧化锆修饰后的玻碳电极还展现了较好的稳定性以及在真实水样检测中的实用性。

Robust PID controller design for time delay processes with peak of maximum sensitivity criteria

The motivation of this work is to obtain single PI/PID tuning formula for different types of processes with enhanced disturbance rejection performance. The proposed tuning formula consistently gives better performance in comparison to several well-known methods at the same degree of robustness for stable, integrating and unstable processes. For the selection of the closed-loop time constant(τc), a guideline is provided over a broad range of time-delay/time-constant ratios on the basis of the peak of maximum sensitivity(Ms). An analysis has been performed for the uncertainty margin with the different process parameters for the robust controller design. It gives the guideline of the Ms-value settings for the PI controller designs based on the process parameters uncertainty. Furthermore, a relationship has been developed between Ms-value and uncertainty margin with the different process parameters(k, τ and θ). Simulation study has been conducted for the broad class of processes and the controllers are tuned to have the same degree of robustness by measuring the maximum sensitivity, Ms, in order to obtain a reasonable comparison.

Fully differential optoelectronic integrated receiver implemented by 0.35μm standard CMOS process

A high-bandwidth, high-sensitivity fully differential optoelectronic integrated receiver is implemented in a chartered 3.3 V standard 0.35μm analbg CMOS process. To convert the incident light into a pair of fully differential photo-currents, a novel fully differential photodetector is proposed, which is composed of two completely identical photodiodes. The mea- surement results show that the receiver achieves a 1.11 GHz 3 dB bandwidth and a -13 dBm sensitivity for a 10-12 bit error at 1.5 Gb/s data rate under illumination by 850 nm incident lights.

High-Sensitivity Acquisition of Ultrahigh Dynamic Direct Sequence Spread Spectrum Signals in Space Communications

According to the requirements of the high-sensitivity acquisition of Direct Sequence Spread Spectrum(DSSS) signals under ultrahigh dynamic environments in space communications, a three-dimensional joint search of the phase of Pseudo-Noise-code(PN-code),Doppler frequency and its rate-of-change is presented to achieve high sensitivity in sensing high-frequency dynamics. By eliminating the correlation peak loss caused by ultrahigh Doppler frequency and its rate-of-change offset,the proposed method improves the acquisition sensitivity by increasing the non-coherent accumulation time. The validity of the algorithm is proved by theoretical analysis and simulation results. It is shown that signals with a carrier- to-noise ratio as low as 39 dBHz can be captured with high performance when the Doppler frequency is up to ±1 MHz and its rate-of-change is up to ±200 kHz/s.

High-sensitivity temperature sensor based on long-period fiber grating

Temperature sensitivity is greatly improved by taking the following three measures： proper long-period fiber grating （LPFG） whose strain coefficient of the core is larger than that of the cladding is employed, the LPFG is coated with a thin film of the material whose refractive index decreases with the temperature, and the sensor is encapsulated by metal material whose thermal expansion coefficient is large. By computer simulation, a measured temperature coefficient of 0.2375 nm/℃ and a temperature resolution less than 0.1 ℃ are obtained.

High Sensitivity Acquisition Algorithm for DSSS Signal with Data Modulation

In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances in terms of data channel coding which might result in a signal structure where the symbol duration is shorter than the pseudo code period. This can generate some difficulties in the DSSS signal acquisition due to the polarity inversion caused by the data modulation. To eliminate the influence due to polarity inversion, this paper proposes a novel acquisition algorithm based on the simultaneous search of the code phase, data phase and Doppler frequency. In the proposed algorithm the data phase is predicted and the correlation period for the coherent integration can be set equal to the symbol duration. Then non-coherent accumulation over different symbol is implemented in order to enhance the acquisition algorithm sensitivity; the interval of non-coherent accumulation is the least common multiple between the symbol duration and the pseudo code period. The algorithm proposed can largely minimize the SNR loss caused by data polarity inversion and enhance acquisition performance without a noticeable increase in hardware complexity. Theoretical analysis, simulation and measured results verify the validity of the algorithm.

Design and optimization of vector coil sensor suited to magnetometric resistivity method

Magnetometric resistivity(MMR)method is a new way to detect dam leakage.The coil sensor is generally used to collect data in geophysical exploration methods.Given the characteristics of accurate vector data requirements and high sensitivity requirement,a three-component MMR air-core coil sensor is designed.Through the analysis of sensor sensitivity and coil structure parameters,the coil structure and turn number are designed.By analyzing the noise source of the sensor,a suitable amplifier is selected to reduce the background noise of the system.Through the analysis of the three-component non-orthogonal angles,the parameters of the non-orthogonal angles of the coils are corrected.Finally,a three-component MMR induction magnetic field sensor is designed.The volume of the sensor is controlled at 0.027 m 3.The background noise of X、Y and Z are 5.030435 nV/Hz@380 Hz and magnetic field sensitivities are 0.18995 pT/Hz@380 Hz.The three channels have good consistency,and the three-component nonorthogonal angles correction error of three components is controlled within 0.2%.

LMI Approach to Mixed H_/H_∞ Fault Detection Observer Design

To investigate the robust fault detection （RFD） observer design for linear uncertain systems, the H_index and H∞ norm are used to describe this observer design as optimization problems. Conditions for the existence of such a fault detection observer are given in terms of matrix inequalities. The solution is obtained by new iterative linear matrix inequality （ILMI） algorithms. The RFD observer design over finite frequency range in which Of does not have full column rank for a system is also considered. Numerical example demonstrates that the designed fault detection observer has high sensitivity to the fault and strong robustness to the unknown input.

The diagnostic value of tumor abnormal protein and high sensitivity C reactive protein in screening for endometrial cancer with endometrial thickness less than 8 mm

Objective This study aimed to combine tumor abnormal protein(TAP) and high-sensitivity C-reactive protein(hs-CRP) level detection to diagnose endometrial cancer in patients with endometrial thickness less than 8 mm, and to provide a reference for clinical screening and diagnosis. Methods Clinical data from 19 cases of endometrial cancer, diagnosed on the basis of pathological findings, were collected from September 2014 to December 2015. The inclusion criteria were as follows: the patients were first diagnosed with endometrial thickness less than 8 mm and were all in menopause. Perimenopausal patients(n = 26) with uterine fibroids seen during the same period were selected as a control group. Serum TAP and hs-CRP levels of the patients in the two groups were simultaneously determined on admission. Results We found that both TAP and hs-CRP levels in the experimental group were higher than those in the control group [(182.95 ± 72.14) μm^2 vs.(133.19 ± 55.18) μm^2, P = 0.019;(7.52 ± 19.03) mg/L vs.(1.66 ± 2.31) mg/L, P = 0.136]. The sensitivity of TAP for the diagnosis of endometrial cancer was 73.68%, the specificity was 69.23%, and the Youden index was 0.4291. The diagnostic sensitivity and specificity of hs-CRP was 15.79% and 100%, respectively, and the Youden index was 0.1579. After plotting the receiver operating characteristics curves, the optimal cut-off value for TAP in diagnosing endometrial cancer was found to be 160.662 μm^2 and that for hs-CRP was 1.07 mg/L. Conclusion For patients suspected of having endometrial cancer with endometrial thickness less than 8 mm, combined detection of TAP and hs-CRP levels can be used as a screening tool and can provide new ideas regarding clinical diagnosis and treatment.

Reliability and sensitivity of bogie frame of high-speed train with strength degradation

High-speed bogie frame is a key mechanical component in a train system. The reliability analysis of the bogie is necessary to the safety of high-speed train. Reliability analysis of a bogie frame was considered. The equivalent load method was employed to account for random repeated loads in structural reliability analysis. Degradation of material strength was regarded as a Gamma process. The probabilistic perturbation method was, then, employed for response moment computation. Example of a high-speed train bogie structure under time-variant load was employed for reliability and sensitivity analyses. Monte-Carlo simulation verifies the accuracy and efficiency of the proposed method in time-variant reliability analysis. The analysis results show that the reliability calculation considering the strength degradation and repeated load is closer to the practicality than the method of considering reliability calculation only. Its decreasing velocity is faster than the traditional reliability. The reliability sensitivity value changes over time. The analysis results provide a variation trend of reliability and sensitivity to design and usage of bogie frame.

Sensitive factors research for track-bridge interaction of Long-span X-style steel-box arch bridge on high-speed railway

X-style arch bridge on high-speed railways(HSR)is one kind of complicated long-span structure,and the track-bridge interaction is essential to ensure the safety and smoothness of HSR.Taking an X-style steel-box arch bridge with a main span of450 m on HSR under construction for example,a new integrative mechanic model of rail-stringer-cross beam-suspenderpier-foundation coupling system was established,adopting the nonlinear spring element simulating the longitudinal resistance between track and bridge.The transmission law of continuous welded rail(CWR)on the X-style arch bridge was researched,and comparative study was carried out to discuss the influence of several sensitive factors,such as the temperature load case,the longitudinal resistance model,the scheme of longitudinal restraint conditions,the introverted inclination of arch rib,the stiffness of pier and abutment and the location of the rail expansion device.Calculating results indicate that the longitudinal resistance has a significant impact upon the longitudinal forces of CWR on this kind of bridge,while the arch rib’s inclination has little effect.Besides,temperature variation of arch ribs and suspenders should be taken into account in the calculation.Selecting the restraint system without longitudinally-fixed bearing and setting the rail expansion devices on both ends are more reasonable.

Low Concentration of CO Gas Sensor by Atomic Layer Deposition

In this study, Al/TiO2/Al2O3/p-Si was fabricated as a gas sensor. TiO2 and Al2O3 were grown by Atomic Layer Deposition method. The prepared film was tested in various gas concentrations at different operating temperatures ranging between 27 ℃ to 177 ℃. The sensitivity increases with increasing gas concentration and operating temperature which have a direct effect on sensing surface. The gas sensing mechanism could be explained with the surface controlled type based on the change of the electrical conductance of the semiconducting material. This mechanism is controlled by CO molecules and the amount of chemisorbed oxygen on the surface which is associated with temperature. Sample exhibits the basic parameters for gas sensors applications which are good stability, reproducibility and high sensitivity to CO gas which are. In addition, the response and recovery times are measured 19 and 26 s, respectively.

An all optical fiber gas sensor of NH3 and CO based on based on the spectral absorption and harmonic detection

An all optical fiber gas sensor is presented to detect the concentration of NH3 and CO. Based on the spectral absorption, The wideband light source is used to reflect two narrowband spectra by fiber grating of different duty. and piezoelectric ceramics to obtain narrowband output light. The high sensitivity detection can be measured from the second harmonic signal. The two narrowband spectra are corresponding to the absorption spectra of NH3 and CO. Concentration detection are realized by the detection of variety of light intensity. Sensitivity is proved and cost is reduced.

Tolerance, Oxygen Consumption and Ammonia Excretion of Ophiopholis sarsii vadicola in Different Temperatures and Salinities

There are more than 2000 species of brittle stars in the world. For most of them, many scientific questions including basic characteristics of eco-physiology are still unknown. In the present study, Ophiopholis sarsii vadicola acclimated at 15 ℃, salinity 31, were assessed for temperature monia excretion were studied at different temperatures （5, 10, and salinity tolerance. Its oxygen consumption and am- 15, 20, 25℃） and salinities （25, 30, 35）. O. sarsii vadi- cola could tolerate 0-24℃ and no brittle star was dead in the salinity range of 19-48 in the experimental situation. Two-way ANOVA showed that the oxygen consumption and ammonia excretion normalized with both dry mass and wet mass, Q10, which is used to describe the temperature sensitivity of respiration, and moisture content were significantly affected by temperature and salinity, and the combined effects of the two factors were significant. Stepwise multiple regression analysis revealed that logarithmic oxygen consumption and ammonia excretion showed a significant positive relationship with logarithmic temperature and salinity. The logarithmic moisture content of the brittle stars showed an inverse relationship with logarithmic salinity, but a positive relationship with logarithmic temperature. This suggests that the tolerance of temperature and salinity of brittle stars is closely related to their living environment, and that the effects of temperature on oxygen consumption are more significant at higher salinity, and that the ammonia excretion is less affected by salinity at lower temperatures.