染料增感聚苯胺半导体薄膜的光电性能

采用电化学方法，利用有机染料对聚苯胺进行有机染料增感，制备出不同增感性能的聚苯胺薄膜。采用红外吸收光谱对增感后的聚苯胺的结构和性能进行了表征，对其在紫外－ 可见光区的吸收特性进行了研究。结果表明，染料增感后的聚合物薄膜电导率分别为：直接耐晒蓝增感为０ ．１４２ Ｓ／ｃｍ ；直接耐晒翠蓝增感为１ ．０５０ Ｓ／ｃｍ ；直接耐晒黑增感为０ ．７９６ Ｓ／ｃｍ ； 四羧基酞菁增感为１ ．２２０ Ｓ／ｃｍ 。这些增感均可使聚苯胺在可见光谱范围内的光吸收增强，较大幅度地改善聚苯胺的光谱响应范围。

论蜀道人居环境景观承载的文化心理

本文以晚清时期蜀道沿线人居环境景观为研究对象,从文化心理与价值观念的角度,探讨人居环境景观的聚合感。首先,本文分析了人居环境景观的聚合感在民居建筑建造形式和场地空间中的体现,以及这种聚合感在华夏人居环境心理中的传承。其次,本文通过研究传统文化和哲学对于聚合感的解读,将聚合感理解为人们对空间环境中积聚性、亲和度、温暖感的一种综合性感知与体悟。最后,本文以晚清时期蜀道沿途人居环境景观为例,从场镇、村庄两方面详细论述了这种聚合感的体现。

紫激光直接制版版材研究与发展综论

从drupa2000紫激光二极管推出使用至今,二极管紫激光的波长已达到紫外区(350nm)。用于计算机直接制版(CTP)的紫激光具有光点小、分辨率高、曝光性能稳定,激光二极管体积小、寿命长、模块化程度高、易维修更换并且制版成像系统价格便宜的优点,这些优点使得紫激光乃至紫外激光CTP系统和版材具有广阔的发展空间。本文主要介绍几类可用于紫激光,特别是目前比较成熟的适用于405nm光源的感光成像体系。从光谱匹配性、感度、技术成熟度来看,高感度的重氮萘醌阳图体系、重氮树脂PVA树脂的传统阴图体系、高感度的光聚合体系是主要研究发展方向。

网络社群成员的共睦态体验对潜水意向的影响研究

网络社群中,大部分成员是潜水者,他们只浏览他人发布的信息而不主动参与贡献或分享信息,如何激发和转化潜水者值得深入研究。本研究基于人类学的共睦态体验理论,通过4个研究探究了网络社群成员的共睦态体验对他们潜水意向的影响。研究发现:第一,网络社群成员的共睦态体验有助于降低其潜水意向;第二,成员聚合的自我扩展感在共睦态体验影响潜水意向的关系中起中介作用;第三,成员的信息过载感调节了共睦态体验对聚合自我扩展感的直接影响和通过聚合自我扩展感对潜水意向的间接影响,即当社群成员感到较强的信息过载感时,共睦态体验对聚合的自我扩展感的提升作用,及通过聚合的自我扩展感降低潜水意向的中介效应都会随之减弱,反之则增强。本文针对现实中的潜水现象,深入讨论了共睦态体验、聚合的自我扩展感、信息过载感等网络社群成员的体验和自我感对潜水意向的影响,不仅丰富了潜水现象的理论研究,也为网络社群的运营管理和信息的流通传播提供了积极的实践启示。

Update on occult hepatitis B virus infection

The event of mutations in the surface antigen gene of hepatitis B virus(HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core(anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection(OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction(PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for:(1) patients with a previous history of chronic or acute HBV infection;(2) patients co-infected with hepatitis C virus/human immunodeficiency virus;(3) patients undergoing chemotherapy or anti-CD20 therapy;(4) recipients of organ transplant;(5) blood donors;(6) organ transplant donors;(7) thalassemia and hemophilia patients;(8) health care workers;(9) patients with liver related disease(cryptogenic);(10) hemodialysis patients;(11) patients undergoing lamivudine or interferon therapy; and(12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world.

SPE Membrane Electrode and Its Application to Chemical Sensor

The structure and proton conducting mechanism of solid polymer electrolyte (SPE) are described. Since the conductivity of electrolyte is important in SPE electrochemical cell research and development, we investigate quantitatively the conductivity of Nafion membrane and its dependence on temperature and relative humidity. Experimental results show that the conductivity of Nafion membrane increases with temperature and relative humidity. We also reports on the preparation and development of SPE membrane electrode with the emphasis on the mixture pressing method and impregnation-reduction process to prepare SPE composite electrode assemblies and their application to electrochemical sensors. We also investigate and fabricate a potentiometric electrochemical sensor of hydrogen and ethylene to measure the hydrogen and ethylene partial pressure.

Preparation and Characterization of Temperature-Sensitive Hydrogels Composites by Coating Method

In this study,the hydrogels composites with coatings based on a temperature-sensitive linear copolymer of N-tert-butylacrylamide(NTBA)and acrylamide(AAm)on cotton fabrics have been developed.The cotton fabrics were coated using aqueous solution of the linear copolymer,1,2,3,4-butanetertracarboxylic acid(BTCA)as a cross-linker and sodium hypophosphite(SHP)as a catalyst,followed by drying and curing.The effects of cross-linking reaction conditions in coating process on water-impermeable ability of coated cotton fabrics were investigated in detail.The results indicate that the coated fabrics have temperature sensitivity.The coatings of poly(NTBA-co-AAm)hydrogels were bonded on the surface of the cotton fabrics,as verified by SEM and optical microscopy,which gave the water-impermeable ability to the hydrogels composites.Moreover,the hydrogels formed in the coating process also identified that - COOH of BTCA reacted with -NH2 in the linear polymer and formed three-dimensional network hydrogels.FTIR and XPS were used to characterize the cross-linking reaction of - COOH of BTCA and - OH of cellulose.

Viscoelastic Analysis of a Surface Acoustic Wave Gas Sensor Coated by a New Deposition Technique

An analysis of the response of surface acoustic wave sensors coated with polymer film based on new coating deposition （self-assemble and molecularly imprinted technology） is described and the response formulas are hence deduced. Using the real part of shear modulus, the polymer can be classified into three types： glassy film, glassy-rubbery film and rubbery film, Experimental results show that the attenuation response is in better consistence with the simulation than in Martin＇s theory, but the velocity response does not accord with the calculation exactly. Maybe it is influenced by the experimental methods and environment. In addition, simulations of gas sorption for polymer films are performed. As for glassy film, the SAW sensor response increases with increasing fihn thickness, and the relationship between the sensor response and the concentration of gas is pretty linear, while as for glassy-rubbery flint and rubbery film, the relationship between the sensor sensitivity anti concentration of gas is very complicated. The ultimately calculated results indicate that the relationship between the sensor response and frequency is not always linear due to the viscoelastic prooerties of the polymer.

Preparation and Characterization of Magnetic Resin Made from Chitosan and Cerium

In this study, the water-based ferromagnetic fluid and magnetic resin made from chitosan and cerium complex （MRCCC） were successfully prepared by using the chemical co-precipitation technique and by the reversed-phase suspension cross-linking polymerization. MRCCC presented uniform and narrow panicle size distribution as determined by the Laser Panicles Sizer. The Inductively Coupled Plasma-Atomic Emission Spectrometry （ICP-AES）, Fourier transform infrared spectroscopy （FT-IR）, differential scanning calorimetry （DSC） and X-ray powder diffraction （XRD） study demonstrated that there were iron and cerium existing in MRCCC. The movement of MRCCC under magnetic field proved its magnetic property. The swelling kinetics in water or solutions with different pH indicated that MRCCC could be applied in solutions with pH greater than 1.0. The ferromagnetic fluid particles were stable in MRCCC soaked in solutions with pH 〉2.0. In view of these results, MRCCC can be used as material for separation, clarification, adsorption, sustained release and hydrolysis activity.

RELATIONSHIP BETWEEN HUMAN PARVOVIRUS B19 INFECTION AND APLASTIC ANEMIA

Objective. To explore the relationship between human parvovirus B19 (HPV B19) infection and aplastic anemia (AA) and to investigate the role of HPV B19 in the occurrence of AA. Methods. The presence of HPV B19 DNA was detected in the peripheral blood samples of 60 patients with AA (children 38 and adults 22) by nested polymerase chain reaction (PCR) assay, and 30 healthy persons were selected as control. Results. Sixteen (26.7％ ) of 60 AA cases were HPV B19 DNA positive, while all the samples in the control group were negative for HPV B19 (P = 0.000914). Among the case group, the positive rates of HPV B19 DNA were 21.4％ (6 / 28), 30.0％ (3 / 10), 20.0％ (1 / 5) and 35.3％ (6 / 17) in children acute AA (AAA), children chronic AA (CAA), adults AAA and adults CAA patients respectively, which were significantly higher than that in the control group. Furthermore, there was no remarkable difference between children AA and adults AA in the 16 HPV B19 DNA positive patients; neither was there between AAA and CAA. Conclusions. HPV B19 infection is not only correlated with the occurrence of children AAA and CAA, but also with adults AAA and CAA, and might be an important viral cause for AA in humans.

Crimean-Congo Hemorrhagic Fever: An Overview

Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic viral infection that is a serious threat to humans. The disease is widely distributed in Africa, Asia, and Europe and has developed into a serious public health concern. Humans become infected through the bites of ticks, by contact with a patient with CCHF, or by contact with blood or tissues from viremic livestock. Microvascular instability and impaired hemostasis are the hallmarks of the infection. Infection in human begins with nonspecific febrile symptoms, but may progress to a serious hemorrhagic syndrome with high mortality rates. Enzyme-linked immunoassay (ELISA) and polymerase chain reaction (PCR) are the most used and specific tests for the diagnosis. The mainstay of treatment is supportive. Although definitive studies are not available, ribavirin is suggested to be effective especially at the earlier phase of the infection. Uses of universal protective measures are the best way to avoid the infection. In this review, all aspects of CCHF are overviewed in light of the current literature.

Using the polymerase chain reaction coupled with denaturing gradient gel electrophoresis to investigate the association between bacterial translocation and systemic inflammatory response syndrome in predicted acute severe pancreatitis

AIM: To investigate the use of PCR and DGGE to investigate the association between bacterial translocation and systemic inflammatory response syndrome in predicted severe AP.METHODS: Patients with biochemical and clinical evidence of acute pancreatitis and an APACHE Ⅱ score ≥8 were enrolled. PCR and DGGE were employed to detect bacterial translocation in blood samples collected on d1,3, and 8 after the admission. Standard microbial blood cultures were taken when there was clinical evidence of sepsis or when felt to be clinically indicated by the supervising team.RESULTS: Six patients were included. Of all the patients investigated, only one developed septic complications;the others had uneventful illness. Bacteria were detected using PCR in 4 of the 17 collected blood samples. The patient with sepsis was PCR-positive in two samples (taken on d 1 and 3), despite three negative blood cultures. Using DGGE and specific primers, the bacteria in all blood specimens which tested positive for the presence of bacterial DNA were identified as E coli.CONCLUSION: Our study confirmed thatunlike traditional microbiological techniques, PCR can detect the presence of bacteria in the blood of patients with severe AP. Therefore, this latter method in conjunction with DGGE is potentially an extremely useful tool in predicting septic morbidity and evaluating patients with the disease. Further research using increased numbers of patients, in particular those patients with necrosis and sepsis, is required to assess the reliability of PCR and DGGE in the rapid diagnosis of infection in AP.

Development of Uric Acid Sensor Based on Molecularly Imprinted Polymetl^acrylic Acid-Modified Hanging Mercury Drop Electrode

Development of uric acid sensor based on molecularly imprinted polymer （MIP） was studi ed. The sensor was developed by coating the imprinted polymethacrylic acid on the surface of a hanging mercury drop ele, ctrode （HMDE） at -1 V （vs. Ag/AgCI） during 60 s. Uric acid was accumulated on the modified electrode at -1 V （vs. Ag/AgC1） during 60 s in acetate buffer pH = 5 and stripped at scan rate of 59 mV/s. Oxidation of uric acid on the surface of modified electrode is irreversible through the diffusion controlled process and polymethacrylic acid is a non-electrical conducting polymer. The current signal obtained from Ehe analysis of uric acid by using HMDE is higher than that of the HMD-palymethacrylic acid （polyMAA）, HMD-MIP and HMD-non imprinted polymer （NIP） electrode. The HMD-MIP has demonstrated its performance as a sensitive voltammetric sensor for uric acid. The modified electrode has been tested for the determination of uric acid in the serum sample with recovery percentage of 95.7% （n = 2）. The limit of detection obtained was 6.0 x 10-10 M.

A Cooperative MIMO Transmission Scheme for Cluster-based Wireless Sensor Networks

Wireless sensor network is becoming more and more popular in recent years, but energy- constrained characteristic of sensor nodes is one of the critical issues that we must consider in system design. In this paper, a cluster-based virtual VBLAST transmission scheme is proposed to achieve energy savings for energy-constrained wireless sensor networks. In the proposed scheme, instead of using cluster member as cooperative nodes, multiple cluster heads cooperate to form virtual antenna array so that V-BLAST based virtual MIMO transmission can be implemented. Based on the communication energy consumption model, a way to optimize the parameters for the scheme is given. In addition, detailed simulation is performed to evaluate the performance of the proposed scheme for both densely and sparsely deployed sensor networks. Theoretical analysis and simulation results verify the energy efficiency of the proposed scheme.

Prognostic role of sensitive-to-apoptosis gene expression in rectal cancer

AIM:To investigate the association between prognosis of rectal cancer treated with chemoradiotherapy(CRT) and expression of sensitive-to-apoptosis(SAG),B-cell lymphoma-extra large(Bcl-X L) and Bcl-2 homologous antagonist/killer(Bak).METHODS:Real-time quantitative polymerase chain reaction was used to determine the expression of proteins of interest,namely SAG,Bcl-X L,Bak and β-actin,in rectal carcinoma patients who had a follow-up period of 3 years after CRT.Biopsy specimens were excised from the rectal tumor preceding CRT.RESULTS:SAG,Bcl-X L and Bak proteins showed significant correlations with each other.In multivariate analysis,patients with high vs low SAG expression showed a statistically significant difference in 2-year survival rates:56% vs 73%,respectively(P = 0.056).On the other hand,there were no significant correlations between the expression levels of all three genes and metastatic rates or tumor responses to CRT.Mean overall survival in the patients with elevated SAG expression was 27.1 mo ± 3.9 mo [95% confidence interval(CI):19.3-34.9],and in patients with reduced expression,it was 32.1 mo ± 2.5 mo(95% CI:27.3-36.9).The corresponding values for Bcl-X L were 28.0 mo ± 4.1 mo(95% CI:19.9-36.1) and 31.7 mo ± 2.9 mo(95% CI:26.0-37.5),and those for Bak were 29.8 mo ± 3.7 mo(95% CI:22.5-37.2) and 30.6 mo ± 2.4 mo(95% CI:25.5-35.0),respectively.CONCLUSION:Two-year survival rates significantly correlated with low SAG expression,and SAG may be a candidate gene for good prognosis,independent of therapeutic response of different individuals.

Force Sensing Resistor and Its Applicationto Robotic Control

Abstract: The force sensing resistor (FSR) and its con’struction and characteristic are described. By using the optimal electronic interface, the end result which is a direct proportionality between force and voltage is obtained. The circuits of application for force and position measurements in the robotic control are given. The experiment that FSRs are placed on the fingers of BH - 1 dexterous hand as tactile sensors to measure the contacting forces shows FSR’s force sensitivity is optimized for use in the control of robot contacting with environment.

Adsorption of Chromium （Ⅵ） from Aqueous Solution Using Zeolite/Chitosan Hybrid Composite

This study investigated the adsorption ability of ZCHC （zeolite/chitosan hybrid composite） as adsorbent for chromium （Cr（Ⅵ））, ZCHC was prepared with sol-gel method by mixing zeolite and chitosan. Adsorption experiment from aqueous solutions containing known amount of Cr（Ⅵ） using zeolite, chitosan and ZCHC was explored to evaluate the efficiency of ZCHC as adsorbent for Cr in a batch system. The amount of Cr（Ⅵ） adsorbed at different pH values, initial concentrations, adsorbent dosages, and contact times were determined by ICP-AES （inductively coupled plasma-atomic emission spectrometry） in order to determine the optimum conditions for Cr（Ⅵ） adsorption. Furthermore, the adsorption mechanism of Cr（Ⅵ） by zeolite, chitosan and ZCHC was investigated by applying Langmuir and Freundlich isotherm equations to the data obtained. In addition, the rates of adsorption were found to conform to pseudo-second order kinetics.

Effects of temperature on MWCNTs/PDMS composites based flexible strain sensors

Conductive polymer composites(CPCs)are widely used in the flexible strain sensors due to their simple fabrication process and controllable sensing properties.However,temperature has a significance impact on the strain sensing performance of CPCs.In this paper,the strain sensing characteristics of MWCNTs/PDMS composites under temperature loading were systematically studied.It was found that the sensitivity decreased with the increase of temperature and the phenomenon of shoulder peak also decreased.Based on the theory of polymer mechanics,it was found that temperature could affect the conductive network by changing the motion degree of PDMS molecular chain,resulting in the change of sensing characteristics.Finally,a mathematical model of the resistance against loading condition(strain and temperature),associated with the force−electrical equivalent relationship of composites,was established to discuss the experimental results as well as the sensing mechanism.The results presented in this paper was believed helpful for the further application of strain sensors in different temperature conditions.

Detection of the Pandemic H1N1/2009 Influenza A Virus by a Highly Sensitive Quantitative Real-time Reverse-transcription Polymerase Chain Reaction Assay

A quantitative real time reverse-transcription polymerase chain reaction （qRT-PCR） assay with specific primers recommended by the World Health Organization （WHO） has been widely used successfully for detection and monitoring of the pandemic H1N1/2009 influenza A virus. In this study, we report the design and characterization of a novel set of primers to be used in a qRT-PCR assay for detecting the pandemic H1N1/2009 virus. The newly designed primers target three regions that are highly conserved among the hemagglutinin （HA） genes of the pandemic HlN1/2009 viruses and are different from those targeted by the WHO-recommended primers. The qRT-PCR assays with the newly designed primers are highly specific, and as specific as the WHO-recommended primers for detecting pandemic H1N1/2009 viruses and other influenza viruses including influenza B viruses and influenza A viruses of human, swine, and raccoon dog origin. Furthermore, the qRT-PCR assays with the newly designed primers appeared to be at least 10-fold more sensitive than those with the WHO-recommended primers as the detection limits of the assays with our primers and the WHO-recommended primers were 2.5 and 25 copies of target RNA per reaction, respectively. When tested with 83 clinical samples, 32 were detected to be positive using the qRT-PCR assays with our designed primers, while only 25 were positive by the assays with the WHO-recommended primers. These results suggest that the qRT-PCR system with the newly designed primers represent a highly sensitive assay for diagnosis of the pandemic HIN1/2009 virus infection.

A Study on Diagnosis of Mycoplasma Hominis in The Urogenital Tract By Nested Polymerase Chain Reaction with First Void Urine in Men

Objectives: To evaluate thc efficacy of nested polymerasechain reaction (PCR) with first void urine (FVU) for thediagnosis of Mycoplasma hominis in male patients. Methods: Matched FVU specimens and urethral swabs werecollected from 194 male patients with NongonococcalUrethritis and tested by nested PCR and cell culture. Cellculture was used as a gold standard for evaluating other assaytechniques. Results: For FVU nested PCR assay and FVU cell culture,our results showed that the sensitivity was 100% and 93.3%;specificity was 97.0% and 98.2%; positive predictive value(PPV) was 85.7% and 90.3%, negative predictive value (NPV)was 100% and 98.8%, respectively. The total consistencybetween the two techniques was 97.4%. Conclusions: For the diagnosis of Mycoplasma hominis inmen, nested PCR detecting FVU is a highly sensitive andspecific method. First void urine can replace swab culture orPCR in terms of acceptability and feasibility.