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Design of a low power GPS receiver in 0.18 μm CMOS technology with a ΣΔ fractional-N synthesizer

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 444-449页

作者： Di LI yin-tang yang Jiang-an WANG Bing LI Qiang LONG Jary WEI Nai-di WANG Lei WANG Qian-kun LIU Da-long ZHANG School of Microelectronics Xidian University Xi 'an 710071 China Huaxun Microelectronics Corporation Xi 'an 710075 China

A 19 mW highly integrated GPS receiver with a ΣΔ fractional-N synthesizer is presented in this paper.Fractional-N frequency synthesizer architecture was adopted in this work, to provide more degrees of freedom in the synthesizer design.A high linearity low noise amplifier(LNA) is integrated into the chip.The radio receiver chip was fabricated in a 0.18 μm complementary metal oxide semiconductor(CMOS) process and packaged in a 48-pin 2 mm×2 mm land grid array chip scale package.The chip consumes 19 mW(LNA1 excluded) and the LNA1 6.3 mW.Measured performances are:noise figure36 dB, and-108 dBc/Hz @ 1 MHz phase noise offset from the carrier.The carrier noise ratio(C/N) can reach 41 dB at an input power of-130 dBm.The chip operates over a temperature range of-40, 120 °C and ±5% tolerance over the CMOS technology process.

关键词： GPS receiver ΣΔ fractional-N synthesizer Image rejection Phase noise

Discrete multi-step phase hologram for high frequency acoustic modulation

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Chinese Physics B 2024年第1期33卷 488-495页

作者：周梦晴李照希李怡王业成张娟谌东东全熠杨银堂费春龙 School of Microelectronics Xidian UniversityXi'an 710071China

Acoustic holograms can recover wavefront stored acoustic field information and produce high-fidelity complex acoustic fields. Benefiting from the huge spatial information that traditional acoustic elements cannot match, acoustic holograms pursue the realization of high-resolution complex acoustic fields and gradually tend to high-frequency ultrasound applications. However, conventional continuous phase holograms are limited by three-dimensional(3D) printing size, and the presence of unavoidable small printing errors makes it difficult to achieve acoustic field reconstruction at high frequency accuracy. Here, we present an optimized discrete multi-step phase hologram. It can ensure the reconstruction quality of image with high robustness, and properly lower the requirement for the 3D printing accuracy. Meanwhile, the concept of reconstruction similarity is proposed to refine a measure of acoustic field quality. In addition, the realized complex acoustic field at 20 MHz promotes the application of acoustic holograms at high frequencies and provides a new way to generate high-fidelity acoustic fields.

关键词： discrete multi-step phase hologram econstruction quality 3D printing accuracy high-fidelity

The Application of Permanent Magnet Synchronous Motor with Small Electrical Time Constant in Fiber Positioner

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Research in Astronomy and Astrophysics 2024年第1期24卷 212-222页

作者： Shaoxiong Guo Yan yang Yanbin yin Yihu tang yang Tian Chao Zhai Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China School of Biomedical Engineering Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China Experiment Center of Engineering and Material Science University of Science and Technology of ChinaHefei 230026China

With the development of cutting-edge multi-object spectrographs,fiber positioners located in the focal plane are being scaled down in size,and miniature hollow-cup Permanent Magnet motors are now being considered as a suitable replacement for Faulhaber Precistep stepper motors.However,the small electrical time constant of such coreless motors poses a challenge,as the problem of severe commutation torque ripple in a fiber positioner running a position loop has been tricky.To overcome this challenge,it is advised to increase the Pulse Width Modulation(PWM)frequency as much as possible to mitigate the effects of the current fluctuation.This must be done while ensuring adequate resolution of the PWM generator.By employing a voltage open-loop field-oriented control based on a modulation frequency of 1 MHz,the drive current only costs 25 m A under a 3.3 V power supply.The sine degree of phase current is immaculate,and the repeat positioning accuracy can reach 2μm.Moreover,it is possible to further shrink the bill of devices and the layout area of the Printed Circuit Board,especially in sizesensitive applications.This device has been developed under the new generation of The Large Sky Area MultiObject Fiber Spectroscopic Telescope.

关键词： instrumentation:adaptive optics instrumentation:spectrographs proper motions reference systems

Mpox(formerly monkeypox):pathogenesis,prevention,and treatment

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Signal Transduction and Targeted Therapy 2024年第1期9卷 234-248页

作者： Junjie Lu Hui Xing Chunhua Wang Mengjun tang Changcheng Wu Fan Ye Lijuan yin yang yang Wenjie Tan Liang Shen Xiangyang Central Hospital Affiliated Hospital of Hubei University of Arts and ScienceHubei ProvinceXiangyang 441021China NHC Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China College of Biotechnology Tianjin University of Science&TechnologyTianjin 300457China Shenzhen Key Laboratory of Pathogen and Immunity National Clinical Research Center for infectious diseaseState Key Discipline of Infectious DiseaseShenzhen Third People’s HospitalSecond Hospital Affiliated to Southern University of Science and TechnologyShenzhen 518112China

In 2022,a global outbreak of Mpox(formerly monkeypox)occurred in various countries across Europe and America and rapidly spread to more than 100 countries and regions.The World Health Organization declared the outbreak to be a public health emergency of international concern due to the rapid spread of the Mpox virus.Consequently,nations intensified their efforts to explore treatment strategies aimed at combating the infection and its dissemination.Nevertheless,the available therapeutic options for Mpox virus infection remain limited.So far,only a few numbers of antiviral compounds have been approved by regulatory authorities.Given the high mutability of the Mpox virus,certain mutant strains have shown resistance to existing pharmaceutical interventions.This highlights the urgent need to develop novel antiviral drugs that can combat both drug resistance and the potential threat of bioterrorism.Currently,there is a lack of comprehensive literature on the pathophysiology and treatment of Mpox.To address this issue,we conducted a review covering the physiological and pathological processes of Mpox infection,summarizing the latest progress of anti-Mpox drugs.Our analysis encompasses approved drugs currently employed in clinical settings,as well as newly identified small-molecule compounds and antibody drugs displaying potential antiviral efficacy against Mpox.Furthermore,we have gained valuable insights from the process of Mpox drug development,including strategies for repurposing drugs,the discovery of drug targets driven by artificial intelligence,and preclinical drug development.The purpose of this review is to provide readers with a comprehensive overview of the current knowledge on Mpox.

关键词： prevention treatment intensified

Complement C1q induces the M2-polarization of tumor-associated macrophages in lung adenocarcinoma

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Genes & Diseases 2024年第4期11卷 145-148页

作者： Yuxiao Song yang Fu Jun Wang Jiazhuo tang Jiaxin yin Zhimin Zhang Qibin Song Bicheng Zhang Cancer Center Renmin Hospital of Wuhan UniversityWuhanHubei 430061China Department of Oncology Xiangyang HospitalHubei University of Chinese MedicineXiangyangHubei 441100China Department of Oncology The First Affiliated Hospital of Shandong First Medical UniversityJinanShandong 250000China

Complement C1q was proved to be able to regulate the polarization of macrophages to the anti-inflammatory phenotype(M2 polarized),acting as an anti-inflammation molecule independent of the classical complement pathway.A high level of C1q expression has been detected in the tumor microenvironment(TME)of diverse tumors,including non-small cell lung cancer,in which C1q could be considered a predictor of poor prognosis.

关键词： C1q lung inflammation

Prefrontocortical Astrocytes Regulate Dominance Hierarchy in Male Mice

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Neuroscience Bulletin 2024年第3期40卷 415-417页

作者： Yong tang Hai-Yan yin Peter Illes School of Acupuncture and Tuina Chengdu University of Traditional Chinese MedicineChengdu 610075China International Joint Research Center on Purinergic Signaling Chengdu University of Traditional Chinese MedicineChengdu 610075China Rudolf Boehm Institute for Pharmacology and Toxicology University of Leipzig04107 LeipzigGermany

Social hierarchy is a general self-organizational scheme in animal societies in which each member achieves a certain status of domination or subordination when getting access to resources,with profound consequences for survival,health,reproductive success,and multiple behaviors[1,2].The prefrontal cortex(PFC)was recognized as a central regulator of neuronal circuits determining the formation of social hierarchy;brain areas upstream of the PFC convey information about social status,and downstream brain regions execute dominance behavior[3].Social deficits have been suggested to be due to an elevation of excitatory/inhibitory(E/l)balance within the mouse dorsomedial(dm)PFC[4].A compensatory increase of inhibitory cell excitability partially rescued social deficits caused by such a disturbance of E/l balance.

关键词： consequences hierarchy determining

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

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Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： Chao Qi Jianqin yin Zhicheng Zhang Jin tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D space.Most graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud data.Existing point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual annotation.To address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given structures.Specifically,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point cloud.Besides,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different granularity.It dynamically splits and merges point groups,resulting in a scene graph with high precision.Experiments show that our methods outperform other baseline methods.They output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity

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Chinese Geographical Science 2024年第3期34卷 453-467页

作者： HUANG Xiaoyan KANG Chenchen yin Chun tang Junqing Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Resource and Environmental Sciences Wuhan UniversityWuhan 430079China International Institute of Spatial Lifecourse Health(ISLE) Wuhan UniversityWuhan 430079China School of Urban Planning and Design Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China Key Laboratory of Earth Surface System and Human-Earth Relations of Ministry of Natural Resources of China Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system.

关键词： transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China

Targeting RAF dimers in RAS mutant tumors:From biology to clinic

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1895-1923页

作者： Huanhuan yin Qiulin tang Hongwei Xia Feng Bi Division of Abdominal Cancer Department of Medical OncologyCancer Center and Laboratory of Molecular Targeted Therapy in OncologyWest China HospitalSichuan UniversityChengdu 610041China

RAS mutations occur in approximately 30%of tumors worldwide and have a poor prognosis due to limited therapies.Covalent targeting of KRAS G12C has achieved significant success in recent years,but there is still a lack of efficient therapeutic approaches for tumors with non-G12C KRAS mutations.A highly promising approach is to target the MAPK pathway downstream of RAS,with a particular focus on RAF kinases.First-generation RAF inhibitors have been authorized to treat BRAF mutant tumors for over a decade.However,their use in RAS-mutated tumors is not recommended due to the paradoxical ERK activation mainly caused by RAF dimerization.To address the issue of RAF dimerization,type II RAF inhibitors have emerged as leading candidates.Recent clinical studies have shown the initial effectiveness of these agents against RAS mutant tumors.Promisingly,type II RAF inhibitors in combination with MEK or ERK inhibitors have demonstrated impressive efficacy in RAS mutant tumors.This review aims to clarify the importance of RAF dimerization in cellular signaling and resistance to treatment in tumors with RAS mutations,as well as recent progress in therapeutic approaches to address the problem of RAF dimerization in RAS mutant tumors.

关键词： RAS mutations RAF dimerization RAF inhibitors Cancer therapy Drug resistance