HBC低热高抗裂大坝混凝土的开发研究

在“九五”国家科技攻关项目“高贝利特（HBC）新型胶凝材料研究”的基础上,进行了HBC低热高抗裂大坝混凝土的开发研究,通过与三峡二期大坝中热水泥（MHC）混凝土的平行对比试验,初步论证了HBC大坝混凝土具有良好的工作性、力学性能和耐久性能。HBC大坝混凝土在相同配合比下的绝热温升将降低3－5℃;抗裂性分析表明,HBC大坝混凝土具有良好的抗裂能力,是一种可以在水工大体积混凝土工程中推广应用的新型低热高抗裂大坝混凝土。     

ANK2 Hypermethylation in Canine Mammary Tumors and Human Breast Cancer

Canine mammary tumors (CMT) constitute the most common tumor types found in female dogs. Understanding this cancer through extensive research is important not only for clinical veterinary applications, but also in the scope of comparative oncology. The use of DNA methylation as a biomarker has been noted for numerous cancers in the form of both tissue and liquid biopsies, yet the study of methylation in CMT has been limited. By analyzing our canine methyl-binding domain sequencing (MBD-seq) data, we identified intron regions of canine ANK2 and EPAS1 as differentially methylated regions (DMGs) in CMT. Subsequently, we established quantitative methylation specific PCR (qMSP) of ANK2 and EPAS1 to validate the target hypermethylation in CMT tissue, as well as cell free DNA (cfDNA) from CMT plasma. Both ANK2 and EPAS1 were hypermethylated in CMT and highlighted as potential tissue biomarkers in CMT. ANK2 additionally showed significant hypermethylation in the plasma cfDNA of CMT, indicating that it could be a potential liquid biopsy biomarker as well. A similar trend towards hypermethylation was indicated in HBC at a specific CpG of the ANK2 target on the orthologous human region, which validates the comparative approach using aberrant methylation in CMT.     

Improved Breakdown Voltage of Partially Depleted SOI nMOSFETs with Half-Back-Channel Implantation

:FB (floating-body) and BC (body-contact) partially depleted SOI nMOSFETs with HBC(half-back-channel) implantation are fabricated.Test results show that such devices have good performance in delaying the occurrence of the "kink" phenomenon and improving the breakdown voltage as compared to conventional PDSOI nMOSFETs,while not decreasing the threshold voltage of the back gate obviously.Numerical simulation shows that a reduced electrical field in the drain contributes to the improvement of the breakdown voltage and a delay of the "kink" effect.A detailed analysis is given for the cause of such improvement of breakdown voltage and the delay of the "kink" effect.     

Transceiver for Human Body Communication Using Frequency Selective Digital Transmission

This paper presents a transceiver module for human body communications whereby a spread signal with a group of 64 Walsh codes is directly transferred through a human body at a chip rate of 32 Mcps. Frequency selective digital transmission moves the signal spectrum over 5 MHz without continuous frequency modulation and increases the immunity to induced interference by the processing gain. A simple receiver structure with no additional analog circuitry for the transmitter has been developed and has a sensitivity of 250 µV_pp. The high sensitivity of the receiver makes it possible to communicate between mobile devices using a human body as the transmission medium. It enables half‐duplex communication of 2 Mbps within an operating range of up to 170 cm between the ultra‐mobile PCs held between fingertips of each hand with a packet error rate of lower than 10^?6. The transceiver module consumes 59 mA with a 3.3 V power supply.     

A Novel Flexible Antenna at Very High Frequency Band for On-Body Applications

This paper proposes a novel flexible antenna design operating at very high frequency (VHF) band for on-body applications such as human body communication (HBC). The antenna consists of back-to-back E-shaped fractal and complimentary structures designed over a thin flexible substrate. The overall design working on the principle of fractal geometries and capacitive coupling is highly beneficial to achieve better antenna characteristics even at low frequencies around 35 MHz–45 MHz that are being used for HBC application. The proposed antenna obtained a large bandwidth of around 10.0 MHz in air and a bandwidth of around 8.0 MHz during on-body operation. The antenna has been tested in three different scenarios viz. air, on-body single antenna and on-body communication using two antennas. The insertion loss is reduced to a minimum in all three scenarios, which is quite beneficial for better signal transmission. The size miniaturization with high flexibility in such low frequencies has also been achieved in the paper that makes the proposed design suitable for human body communication applications.     

用旋转粘度计法研究HBC水泥浆体的流变性能

本文主要介绍了用旋转粘度计法研究高贝利特水泥(简称 H BC)水泥浆体的流变性能,结果表明, H BC 水泥浆 体的流变性能符合宾汉塑性模式 τ=τ。+μp×γ。随着剪切速率的增加, H BC 水泥浆体与 PC 水泥浆体剪 切应力随之增加; H BC 水泥浆体与 PC 水泥浆体的塑性粘度和剪切应力规律相似,随着水灰比的增加 H BC,水泥 浆体与 PC 水泥浆体的塑性粘度下降。H BC 水泥的剪切应力及塑性粘度均低于 PC。研究表明 H BC 水泥浆体比 PC 　　　　　　水泥浆体具有更优异的工作性。     

一种应用于WBAN的动态自适应网络研究

基于WBAN的技术尚不成熟,提出一种新型WBAN技术方案,将HBC技术与MICS频段结合应用到WBAN中.考虑到体域网中体内节点的能耗约束性,提出了一种应用于WBAN的新型网络,即具有自适应性的基于中继的两跳星型网络;针对WBAN中节点生存周期的重要性,提出一种低能耗的MAC协议——基于TDMA的中继MAC协议.该方案的提出,能够满足WBAN对安全、能耗、可靠性等服务质量(QoS)的要求,且较好地改善了体内节点的网络生存期.     

Fabrication and intermolecular interactions of silk fibroin/hydroxybutyl chitosan blended nanofibers

The native extracellular matrix (ECM) is composed of a cross-linked porous network of multifibril collagens and glycosaminoglycans. Nanofibrous scaffolds of silk fibroin (SF) and hydroxybutyl chitosan (HBC) blends were fabricated using 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) and trifluoroacetic acid (TFA) as solvents to biomimic the native ECM via electrospinning. Scanning electronic microscope (SEM) showed that relatively uniform nanofibers could be obtained when 12% SF was blended with 6% HBC at the weight ratio of 50:50. Meanwhile, the average nanofibrous diameter increased when the content of HBC in SF/HBC blends was raised from 20% to 100%. Fourier transform infrared spectra (FTIR) and (13)C nuclear magnetic resonance (NMR) showed SF and HBC molecules existed in hydrogen bonding interactions but HBC did not induce conformation of SF transforming from random coil form to β-sheet structure. X-ray diffraction (XRD) confirmed the different structure of SF/HBC blended nanofibers from both SF and HBC. Thermogravimetry-Differential thermogravimetry (TG-DTG) results demonstrated that the thermal stability of SF/HBC blend nanofibrous scaffolds was improved. The results indicated that the rearrangement of HBC and SF molecular chain formed a new structure due to stronger hydrogen bonding between SF and HBC. These electrospun SF/HBC blended nanofibers may provide an ideal tissue engineering scaffold and wound dressing.     

A 2Mbps Human Body Communication Transceiver Based on Body Antenna Effect

This paper presents a human body communication (HBC) transceiver for wireless body network applications. The transceiver employs on frequency shift keying (FSK) modulation and operates in 40 MHz–60 MHz which is the resonant frequency of the human body as an antenna. It achieves high performance and stability through establish passive microstrip line and via models and active device-models. The proposed transceiver is designed and fabricated by FR4 printed circuit board (PCB) process, the transceiver has the ability of configurable data rate up to 2 Mbps and it achieves –86 dBm receiving sensitivity at 2 Mbps data rate. Meanwhile, the transceiver output power dynamics range is 34 dB. Furthermore, with a visual interaction interface, the transceiver can be agility use in a variety of scenarios. Its measurements are verified on human body. The result shows that the transceiver has ability to send data from person to person by relying on human body antenna radiation. The transceiver shows great prospect in wireless body area networks (WBAN) for telemedicine and emergency communication.     

ACE-inhibitory and antihypertensive properties of a bovine casein hydrolysate

The aim of this study was to investigate the potential angiotensin converting enzyme (ACE)-inhibitory activity and the antihypertensive effect, after a single oral administration, of a pepsin hydrolysed bovine casein (HBC) and a fraction with molecular mass lower than 3000 Da (HBC < 3000). ACE-inhibitory activity was measured by spectrophotometric assay. These products were orally administered by gastric intubation. The systolic (SBP) and the diastolic blood pressure (DBP) were measured in spontaneously hypertensive rats by the tail cuff method before administration and also 2, 4, 6, 8, and 24 h post-administration. HBC showed a potent ACE-inhibitory activity. This activity was 10 times higher in HBC < 3000. HBC and HBC < 3000 decreased the arterial blood pressure of the rats. The decrease in the SBP observed for HBC (400 mg/kg) or HBC < 3000 (200 mg/kg) was less pronounced than that caused by 50 mg/kg of captopril (antihypertensive positive control). However, the maximal decreases in DBP caused by HBC or HBC < 3000 were as high as the maximum decrease observed for captopril. The antihypertensive effect of these products was transient and reverted 24 h after the administration. HBC and HBC < 3000 exert antihypertensive effect caused by small peptides with ACE-inhibitory activity.