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Optimal pressure-sensitive cuts for surface acoustic waves on langasite

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Science in China(Series F) 2006年第2期49卷 254-261页

作者： HAN tao JI xiaojun SHI Wenkang School of Electronic Information and Electrical Engineering Shanghai Jiaotong University Shanghai200240 China

The crystal langasite manifests its unique advantages and potentials for high temperature applications due to a high electromechanical coupling coefficient, temperature compensated orientations for surface acoustic wave （SAW）, and temperature stability. In order to analyze the pressure-induced frequency shift in SAW resonator type sensors at high temperature, this paper presents the electroelastic wave equations employing the effective material constants for small vibrations superimposed on biases originated from homogeneous temperature and external pressure fields in the Lagrangian description. Incorporated with the first-order perturbation integration, a model including both the mechanical and electrical perturbation items originating from thermal biases and small pressure fields is proposed. This universal model is suitable for substrate with high piezoelectricity and can be applied at either room temperature or high temperature circumstance. The criteria of optimal cuts for SAW pressure sensitivity, i.e., high electromechanical coupling coefficient and low temperature coefficient of delay, are proposed. A thorough investigation in trebly rotated cuts has shown that optimal pressure sensitive crystallographic areas can be obtained. The areas suitable for pressure sensors at room temperature are defined with Euler angles Ω1： φ=0°-0.6°, θ=144.4°-145.8°, ψ =23.2°-24.1°,Ω2： φ=59.4°-61.°, θ=34.2°-36.2°, ψ =24.1°-22.3°,Ω3： φ=119°-120°, θ=143.8°-145.5°, ψ =22.3°-23.5° The areas suitable for pressure sensors at high temperature are defined with Euler angles Ⅰ： φ=8°-30°, θ=24°-36°, ψ =4°-25°Ⅱ： φ=30°-55°, θ=144.4°-158°, ψ =4°-28° A set of experiments employing LGS （0, 150°, 22°） and （0, 90°, 0） has been performed to check the validity of the proposed calculation. The experimental relative sensitivity is in excellent agreement with the theoretical results.

关键词： surface acoustic wave langasite pressure sensitivity high temperature.

Two new drimane sesquiterpenoids from cultures of the basidiomycete Trichaptum biforme

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Natural Products and Bioprospecting 2013年第4期3卷 154-157页

作者： xiao-Yan YANG tao FENG Jian-Hai DING Zheng-Hui LI Yan LI Qiong-Ying FAN Ji-Kai LIU State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Hebei Normal University Hebei 050024China

Two new drimane sesquiterpenoids(1 and 2),as well as five known compounds(3-7),were isolated from the basidiomycete Trichaptum *** structures of new compounds were elucidated by extensive spectroscopic methods,and the known compounds were identified by comparing their spectroscopic data with those reported in the *** cytotoxicities results against five human cancer cell lines of compounds 1 and 2 were negligible.

关键词： Trichaptum biforme drimane sesquiterpenoids cytotoxicity

空载波对STBC-OFDM系统信道估计性能的影响分析与改进

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电子与信息学报 2009年第3期31卷 640-644页

作者：王轶陶小峰张平泛网无线通信教育部重点实验室(北京邮电大学) 北京100876 北京邮电大学无线新技术研究所北京100876

该文分析了空时分组码-正交频分复用(STBC-OFDM)系统中,空载波对基于离散傅里叶变换(DFT)信道估计的性能影响,推导得出空载波影响下信道估计均方误差及误码率的解析式,并提出一种新的信道估计方法,通过时域乘以干扰因子矩阵的逆消除空... 详细信息

该文分析了空时分组码-正交频分复用(STBC-OFDM)系统中,空载波对基于离散傅里叶变换(DFT)信道估计的性能影响,推导得出空载波影响下信道估计均方误差及误码率的解析式,并提出一种新的信道估计方法,通过时域乘以干扰因子矩阵的逆消除空载波引起的混叠,提高信道估计精度。仿真结果与理论结果相符,且表明改进的信道估计算法有效消除均方误差地板现象,提高系统性能。

关键词：正交频分复用信道估计空时分组码空载波

Some progress on understanding the Phanerozoic granitoids in China

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China Geology 2018年第1期1卷 84-108页

作者： tao Wang Ying Tong xiao-xia Wang Jian-ren Mao Hong-rui Zhang He Huang Shan Li Lei Guo Jian-jun Zhang Key Laboratory of Deep-Earth Dynamics Ministry of Natural ResourcesBeijing 100037China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Metallogeny and Mineral Assessment of Ministry of Natural Resources Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Nanjing center China Geological SurveyNanjing 210016China

There are large volumes of the Phanerozoic granitoid rocks in China and neighboring *** recent years,numerous new and precise U-Pb zircon ages have been published for these granitoids,and define many important magmatic events,such as ca.500 Ma granitoid events in the West Junggar,Altai orogens in the NW China,and Qinling orogen in the central *** ages accurately constrain the time of important early Paleozoic,late Paleozoic,early Mesozoic and late Mesozoic magmatic events of the northern,central,western,southern and eastern orogenic Mountains in *** occur various types of granitoids in China,such as talc-alkaline granite,alkali granite,highly-fractionated granite,leucogranite, adakite,and rapakivi *** granites are not only typical Proterozoic as in the North China Craton,but were also emplaced during Paleozoic and Mesozoic in the Kunlun-Qinling orogen,a part of the China Central Orogenic Belt (CCOB).Nd-Hf isotopic tracing and mapping show that granitoids inthe southern Central Asian Orogenic Belt (CAOB)in China (or the Northern China Orogenic Belt)are characterized predominantly by juvenile *** juvenile crust in this orogenic domain accounts for over 50% by area,distinguishing it from other orogenic belts in the world,and those in central (e.g.,Qinling),southwestem and eastern *** on a large amount of new age data,a preliminary granitoid and granitoid-tectonic maps of China have been preliminarily compiled,and an evolutionary framework of Phanerozoic granitoids in China and neighboring areas has been established from the view of assembly and breakup of continental *** ideas on granitoid tectonics has also been proposed and discussed.

关键词： Granitoids Zircon age Spatial-temporal distribution Radiogenic isotopes Orogen

Shannon-type sampling for multivariate non-bandlimited signals

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Science China Mathematics 2013年第9期56卷 1915-1934页

作者： CHEN QiuHui QIAN tao LI YouFa Cisco School of Informatics Guangdong University of Foreign Studies Department of Mathematics Faculty of Science and TechnologyUniversity of Macao College of Mathematics and Information Sciences Guangxi University

In this paper, starting from a function analytic in a neighborhood of the unit disk and based on Bessel functions, we construct a family of generalized multivariate sinc functions, which are radial and named radial Bessel-sinc (RBS) functions being time-frequency atoms with nonlinear phase. We obtain a recursive formula for the RBS functions in R d with d being odd. Based on the RBS function, a corresponding sampling theorem for a class of non-bandlimited signals is established. We investigate a class of radial functions and prove that each of these functions can be extended to become a monogenic function between two parallel planes, where the monogencity is taken to be of the Clifford analysis sense.

关键词： analytic function Fourier transform radial Bessel-Sinc function Shannon sampling

Protein functional-group 3D motif and its applications

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Chinese Science Bulletin 2000年第22期45卷 2044-2052页

作者： Yuzhen Ye tao Xie Dafu Ding Chinese Acad Sci Shanghai Inst Biochem Shanghai 200031 Peoples R China

Representing and recognizing protein active sites sequence motif (1D motif) and structural motif (3D motif) is an important topic for predicting and designing protein function. Prevalent methods for extracting and searching 3D motif always consider residue as the minimal unit, which have limited sensitivity. Here we present a new spatial representation of protein active sites, called 'functional-group 3D motif', based on the fact that the functional groups inside a residue contribute mostly to its function. Relevant algorithm and computer program are developed, which could be widely used in the function prediction and the study of structural-function relationship of proteins. As a test, we defined a functional-group 3D motif of the catalytic triad and oxyanion hole with the structure of porcine trypsin (PDB code: 1mct) as the template. With our motif-searching program, we successfully found similar sub-structures in trypsins, subtilisins and α/β hydrolases, which show distinct folds but share

关键词： functional-group 3D motif RMSD of distance matrix random probability expectation functional prediction.

Acute celiac artery occlusion secondary to blunt trauma:Two case reports

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World Journal of Clinical Cases 2020年第23期8卷 6164-6171页

作者： Hui Li Yu Zhao Yan-An Xu tao Li Jun Yang Ping Hu tao Ai Department of Traumatology Chongqing University Central HospitalChongqing 400080China Department of Radiology Chongqing University Central HospitalChongqing 400080China

BACKGROUND Acute celiac artery(CA)injuries are extremely rare but potentially life-threatening and are more often caused by a penetrating injury rather than a blunt *** clinical manifestation of CA injuries is usually atypical,which easily causes missed diagnosis and ***,there are only a few reports of acute traumatic occlusion of *** CA artery gives off branches to dominate the liver,*** spleen;however,occluded CA did not cause significant organ ischemia,and the compensatory blood flow from the superior mesenteric artery(SMA)played a pivotal *** SUMMARY Herein,we report two cases of acute CA occlusion secondary to severe blunt *** one was a 19-year-old male,suffered from a motorcycle *** complained of dyspnea,and the closed drainage was performed soon after the hemopneumothorax was confirmed by *** tomography(CT)scan revealed hemopneumothorax,multiple rib fractures,right scapular fracture,and liver *** with contrast-enhanced CT suggested perihepatic fluid was significantly increased,and CA was *** the hepatic hemorrhage is associated with hepatic artery injury,the CA was retrogradely opened through the SMA,and then,the right hepatic artery was embolized with coils successfully through the conventional *** implantation was not performed,and the CA occlusion was managed by conservative treatment.A follow-up CT scan 3 mo after discharge showed the origin of CA remained *** two was a 37-year-old man,suffered injury from fall from *** complained of lower back and bilateral heel ***-enhanced CT examination revealed multiple rib fractures,bilateral pneumothorax,fourth lumbar(L4)vertebral burst fracture,and pelvic ***,a small high-density mass in a lesser peritoneal sac and in front of the abdominal aorta was *** reexamination 14 h after admission showed the CA was *** patient was conservatively treat

关键词： Celiac artery Acute occlusion Superior mesenteric artery Multiple trauma Liver injury Case report Collateral branches

Single-port laparoscopic radical prostatectomy： initial experience and technical points to reduce its difficulties

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Chinese Medical Journal 2011年第23期124卷 4092-4095页

作者： WEN Xing-qiao HUANG Wen-tao SITU Jie HU Cheng YE chun-wei GAO Xin Department of Urology Third Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510630 China

Background Laparoendoscopic single-site surgery （LESS） approaches have been reported for treating various kidney and pelvic procedures, and are feasible and effective in selected patients. In this study, we aimed to present the initial experience and evaluate the efficacy of laparoscopic radical prostatectomy performed through a single incision using a multichannel port. Methods Between July 2010 and April 2011, six patients diagnosed with early stage prostate cancer underwent LESS radical prostatectomy （RP） in our institute. A multichannel port was inserted transperitoneally through a 2-cm umbilical incision. Specially articulating and flexible laparoscopic were used. Some technical tricks and points were applied during the operation to overcome the drawbacks and reduce the difficulties of this approach. Two continuous urethrovesical sutures in both sides were performed to complete both lateral aspects of anastomosis. The two ends of the suture threads were fixed by double Lapro-Clips, instead of the difficult knot-tying. Results Total operative time was （265-＋43） minutes. Mean blood loss was （230_＋65） ml. All cases were completed successfully, without conversion to open surgery or adding additional abdomen ports. No patient required a blood transfusion and no intraoperative complications occurred. The Foley catheter was removed at the 14th day （range 12th-16th） after surgery. At the 12th week of follow-up, all patients had an undetectable prostate-specific antigen level. Two patients used 2 or I pad for continence daily; other patients had achieved good continence. Conclusion In selected cases, LESS-RP is feasible and effective; these technic points and the flexible-articulating instruments are helpful to reduce the operation difficulties.

关键词： laparoendoscopic single-site surgery radical prostatectomy prostate cancer

Host cellular signaling induced by influenza virus

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Science China(Life Sciences) 2011年第1期54卷 68-74页

作者： DAI XinXian ZHANG LiShu HONG tao College of Life Science & Bioengineering School of Science Beijing Jiaotong University Beijing 100044 China Institute for Viral Disease Control and Prevention Chinese Centre for Disease Control and Prevention Beijing 100052 China

A wide range of host cellular signal transduction pathways can be stimulated by influenza virus infection. Some of these signal transduction pathways induce the host cell's innate immune response against influenza virus, while others are essential for efficient influenza virus replication. This review examines the cellular signaling induced by influenza virus infection in host cells, including host pattern recognition receptor (PRR)-related signaling, protein kinase C (PKC), Raf/MEK/ERK and phosphatidylinositol-3-kinase (PI3K)/Akt signaling, and the corresponding effects on the host cell and/or virus, such as recognition of virus by the host cell, viral absorption and entry, viral ribonucleoprotein (vRNP) export, translation control of cellular and viral proteins, and virus-induced cell apoptosis. Research into influenza virus-induced cell signaling promotes a clearer understanding of influenza virus-host interactions and assists in the identification of novel antiviral targets and antiviral strategies.

关键词： influenza virus virus-host interaction signal transduction