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Imrecoxib: a novel and selective cyclooxygenase 2 inhibitor with anti-inflammatory effect

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Acta Pharmacologica Sinica 2004年第7期25卷 81-85页

作者： Xiao-hong CHEN, jin-ye bai, Fang SHEN, Ai-ping bai, Zong-ru GUO, Gui-fang CHENG2 Departmentof Pharmacology, Institute of Materia Medica, Chinese Academyof Medical Sciencesand Peking Union Medical College, Beijing 100050, China Department of Pharmacology Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

AIM: To investigate the inhibitory effect of imrecoxib, a synthetic compound of completely new structure, on cyclooxygenase 1 (COX-1) and 2 (COX-2) and its anti-inflammatory effect in vivo. METHODS: The inhibitory effects of imrecoxib on cyclooxygenase 1 and 2 were studied using whole cell assay with murine peritoneal mac- rophages induced by calcimycin and LPS. The inhibitory effects of imrecoxib on mRNA level of COX-1 and COX- 2 in human macrophage cell line U937 were detected by reverse transcription polymerase chain reaction (RT-PCR) analysis. Effects of imrecoxib on acute and chronic inflammation were evaluated in rat carrageenan induced edema model and rat adjuvant-induced arthritis model, respectively. RESULTS: Imrecoxib was found to inhibit COX-1 and COX-2 with IC50 value of 115±28 nmol/L and 18±4 nmol/L, respectively. Imrecoxib was shown to selectively and dose-dependently inhibit COX-2 mRNA level. Imrecoxib effectively inhibited carrageenan-induced acute in- flammation at the doses of 5, 10, and 20 mg·kg-1 ig and adjuvant-induced chronic inflammation at the doses of 10 and 20 mg·kg-1·d-1 ig. CONCLUSION: Imrecoxib is a novel and moderately selective COX-2 inhibitor that pos- sesses anti-inflammatory effect by inhibition of COX-2 mRNA expression.

关键词： imrecoxib cyclooxygenase 1 cyclooxygenase 2 cyclooxygenase inhibitors inflammation

Reliability analysis of multimodal scene matching based on correlation peaks

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Chinese Journal of Aeronautics 2024年第9期37卷 433-447页

作者： Zhirui YU bai ZHU Zhiqiang HAN Yuanxin ye Faculty of Geosciences and Engineering Southwest Jiaotong UniversityChengdu 611756China

The navigation system plays a pivotal role in guiding aircraft along designated routes,ensuring precise and punctual arrival at *** integration of scene matching with an inertial navigation system enhances the capability of providing a dependable guarantee for success-ful accomplishment of flight ***,assuring reliability in scene matching encoun-ters significant challenges in areas characterized by repetitive or weak *** tackle these challenges,we propose a novel method to assess the reliability of scene matching based on the dis-tinctive characteristics of correlation *** proposed method leverages the fact that the sim-ilarity of the optimal matching result is significantly higher than that of the surrounding area,and three novel indicators(e.g.,relative height,slope of a correlation peak,and ratio of a sub peak to the main peak)are determined to conjointly evaluate the reliability of scene *** pro-posed method entails matching a real-time image with a reference image to generate a correlation surface.A correlation peak is then obtained by extracting the portion of the correlation surface exhibiting a significant ***,the matching reliability is determined by considering the relative height,slope,and ratio of the peak *** experimental results with two sets of data demonstrate that the proposed method significantly outperforms traditional approaches in terms of precision,recall,and *** experiments also establish the efficacy of the proposed method in achieving reliable matching in challenging environments characterized by repetitive and weak *** enhancement holds the potential to significantly elevate scene-matching-based navigation.

关键词： Unmanned aerial vehicle Scene matching navigation Multimodal scene matching Correlation peak Reliabilityanalysis

Study on Static Deflection Model of MEMS Capacitive Microwave Power Sensors

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Chinese Journal of Electronics 2024年第5期33卷 1188-1195页

作者： ye jin Debo WANG College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts and Telecommunications College of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications

In this paper, a static deflection model of MEMS cantilever beam is proposed, which can better study the force deformation of micro-electro-mechanical system(MEMS) cantilever beam and the output characteristics of capacitive microwave power sensor. The deflection curve is used to describe the deformation of the cantilever beam and then the overload power and sensitivity of this power sensor are derived. It is found that the overload power decreases with the beam length, and increases with the initial height of beam. The sensitivity increases with the beam length, and has a linear growth relationship with the measuring electrode width. A MEMS dual-channel microwave power sensor is designed, fabricated and measured. At a microwave signal frequency of 10 GHz, the sensitivity of the sensor is measured to be 0.11 V/W for the thermoelectric detection channel and 65.17 fF/W for the capacitive detection channel. The sensitivity calculated by the lumped model is 92.93 fF/W, that by the pivot model is 50.88 fF/W,and that by the deflection model proposed in this work is 75.21 fF/W. Therefore, the theoretical result of the static deflection model is more consistent with the measured result and has better accuracy than the traditional lumped model and pivot model.

关键词： Microwave measurement Micromechanical devices Microelectromechanical systems Sensitivity Voltage measurement Accuracy Deformation Micro-electro-mechanical system (MEMS) cantilever beam Static deflection model Power sensor Overload power

Social Robot Detection Method with Improved Graph Neural Networks

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Computers, Materials & Continua 2024年第2期78卷 1773-1795页

作者： Zhenhua Yu Liangxue bai Ou ye Xuya Cong Institute of Systems Security and Control College of Computer Science and TechnologyXi’an University of Science and TechnologyXi’an710054China

Social robot accounts controlled by artificial intelligence or humans are active in social networks,bringing negative impacts to network security and social *** social robot detection methods based on graph neural networks suffer from the problem of many social network nodes and complex relationships,which makes it difficult to accurately describe the difference between the topological relations of nodes,resulting in low detection accuracy of social *** paper proposes a social robot detection method with the use of an improved neural ***,social relationship subgraphs are constructed by leveraging the user’s social network to disentangle intricate social relationships ***,a linear modulated graph attention residual network model is devised to extract the node and network topology features of the social relation subgraph,thereby generating comprehensive social relation subgraph features,and the feature-wise linear modulation module of the model can better learn the differences between the ***,user text content and behavioral gene sequences are extracted to construct social behavioral features combined with the social relationship subgraph ***,social robots can be more accurately identified by combining user behavioral and relationship *** carrying out experimental studies based on the publicly available datasets TwiBot-20 and Cresci-15,the suggested method’s detection accuracies can achieve 86.73%and 97.86%,*** with the existing mainstream approaches,the accuracy of the proposed method is 2.2%and 1.35%higher on the two *** results show that the method proposed in this paper can effectively detect social robots and maintain a healthy ecological environment of social networks.

关键词： Social robot detection social relationship subgraph graph attention network feature linear modulation behavioral gene sequences

Free-moving-state microscopic imaging of cerebral oxygenation and hemodynamics with a photoacoustic fiberscope

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Light(Science & Applications) 2024年第1期13卷 33-46页

作者： Xiaoxuan Zhong Yizhi Liang Xiaoyu Wang Haoying Lan Xue bai Long jin bai-Ou Guan Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics TechnologyJinan UniversityGuangzhou510632China

We report the development of a head-mounted photoacoustic fiberscope for cerebral imaging in a freely behaving *** 4.5-gram imaging probe has a 9-µm lateral resolution and 0.2-Hz frame rate over a 1.2-mm wide *** probe can continuously monitor cerebral oxygenation and hemodynamic responses at single-vessel resolution,showing significantly different cerebrovascular responses to external stimuli under anesthesia and in the freely moving *** example,when subjected to high-concentration CO_(2) respiration,enhanced oxygenation to compensate for hypercapnia can be visualized due to cerebral regulation in the freely moving *** studies exhibit significantly weakened compensation capabilities in obese *** new imaging modality can be used for investigating both normal and pathological cerebrovascular functions and shows great promise for studying cerebral activity,disorders and their treatments.

关键词： cerebral anesthesia moving

Infrared radiation characteristics of dagger-type hypersonic missile

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Chinese Journal of Aeronautics 2024年第4期37卷 137-150页

作者： Xubo DU Qingzhen YANG Haoqi YANG jin bai Yongqiang SHI School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Hypersonic vehicles emit strong infrared radiation from their high-temperature exhaust plume and body, which is critical for infrared early warning, tracking, and guidance. In this work, a comprehensive analysis is conducted on the factors involved in air dissociation reaction within the shock layer of hypersonic missile heads, as well as the multi-component afterburning effect of the exhaust plume. A novel Reverse Monte Carlo Method(RMCM) is proposed for infrared radiation calculation, which utilizes two-dimensional Low-Discrepancy Sequences(LDS) to improve computational accuracy. The numerical calculations for a dagger-type missile show that afterburning reactions increase the temperature on the centerline of the outlet exhaust plume by about 1000 K. The total infrared radiation intensity of the missile is the highest in the 1–3 μm band, with the hightemperature wall of the nozzle being the primary source of solid radiation, and gas radiation primarily coming from H_(2)O. The radiation intensity of the missile exhaust plume in the 3–5 μm band is the highest, with radiation sources primarily coming from CO_(2), CO, and HCl. Afterburning reactions of the exhaust plume increase the total infrared radiation intensity of the missile by about 0.7times. These results can provide reference for the detection and guidance of hypersonic missiles.

关键词： Hypersonic vehicles Infrared radiation Monte Carlo methods Low-discrepancy sequences Exhaust plume Afterburning

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A self-centering and stiffness-controlled MEMS accelerometer

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Microsystems & Nanoengineering 2024年第1期10卷 27-40页

作者： Yiming jin Zhipeng Ma Ziyi ye Mingkang Li Xudong Zheng Zhonghe jin School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310013China Key Laboratory of Micro/Nano-Satellite Research of Zhejiang Province Hangzhou 310007PR China

This paper presents a high-performance MEMS accelerometer with a DC/AC electrostatic stiffness tuning capability based on double-sided parallel plates(DSPPs).DC and AC electrostatic tuning enable the adjustment of the effective stiffness and the calibration of the geometric offset of the proof mass,respectively.A dynamical model of the proposed accelerometer was developed considering both DC/AC electrostatic tuning and the temperature *** on the dynamical model,a self-centering closed loop is proposed for pulling the reference position of the forceto-rebalance(FTR)to the geometric center of *** self-centering accelerometer operates at the optimal reference position by eliminating the temperature drift of the readout circuit and nulling the net electrostatic tuning *** stiffness closed-loop is also incorporated to prevent the pull-in instability of the tuned low-stiffness accelerometer under a dramatic temperature ***-time adjustments of the reference position and the DC tuning voltage are utilized to compensate for the residue temperature drift of the proposed *** a result,a novel controlling approach composed of a self-centering closed loop,stiffness-closed loop,and temperature drift compensation is achieved for the accelerometer,realizing a temperature drift coefficient(TDC)of approximately 7μg/℃ and an Allan bias instability of less than 1μg.

关键词： stiffness electrostatic centering

GEOSatDB:global civil earth observation satellite semantic database

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Big Earth Data 2024年第3期8卷 522-539页

作者： Ming Lin Meng jin Juanzi Li Yuqi bai Department of Earth System Science Institute for Global Change StudiesMinistry of Education Ecological Field Station for East Asian Migratory BirdsTsinghua UniversityBeijingChina Department of Computer Science and Technology Tsinghua UniversityBeijingChina Tsinghua Urban Institute Tsinghua UniversityBeijingChina

Satellite remote sensing,characterized by extensive coverage,fre-quent revisits,and continuous monitoring,provides essential data support for addressing global *** the past six decades,thousands of Earth observation satellites and sensors have been deployed *** valuable Earth observation assets are contributed independently by various nations and organizations employing diverse *** poses a significant challenge in effectively discovering global Earth observation resources and realizing their full *** this paper,we describe the develop-ment of GEOSatDB,the most complete semantic database of civil Earth observation satellites developed based on a unified ontology model.A similarity matching method is used to integrate satellite information and a prompt strategy is used to extract unstructured sensor *** resulting semantic database contains 127,949 semantic statements for 2,340 remote sensing satellites and 1,021 observation *** global Earth observation capabil-ities of 195 countries worldwide have been analyzed in detail,and a concrete use case along with an associated query demonstration is *** database provides significant value in effectively facilitating the semantic understanding and sharing of Earth observa-tion resources.

关键词： Earth observation satellite sensor semantic representation information extraction

Images for diagnosis Sarcomatoid carcinoma of the renal pelvis in duplex kidney

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Chinese Medical Journal 2011年第13期124卷 2074-2076页

作者： CHEN Ge-ming CHEN Shan-wen XIA Dan LI Jun YAN Sheng jin bai-ye Department of Urology First Affiliated Hospital Medical College of Zhejiang University Hangzhou Zheiiang 310031 China Department of Pathology First Affiliated Hospital Medical College of Zhejiang University Hangzhou Zheiiang 310031 China Department of Surgery First Affiliated Hospital Medical College of Zhejiang University Hangzhou Zheiiang 310031 China

Sarcomatoid transitional cell carcinoma of the renal pelvis is a rare neoplasm with only 14 well-illustrated examples reported previously. Duplex kidney is the most common congenital abnormality of the urinary tract, with an incidence of around 2%. Neoplasia of the renal pelvis in duplex kidney is rare. We reported a case whose sarcomatoid carcinoma originated from the upper portion of the duplicated renal pelvis with hydronephrosis, and total nephroureterectomy with bladder cuff excision surgery of both renal units was carried out. Because of the rare nature of renal pelvic sarcomatoid carcinoma and its apparent lack of response to adjuvant therapy, it is essential to do early diagnosis and early radical surgery to improve survival. It is important to stress the need for frequent and diligent monitoring or treating complex duplex kidney with hydronephrosis of either moiety in case of a risk of havina neoplasias.

关键词： duplicated renal pelvis sarcomatoid transitional cell carcinoma

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