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Ruptured intracranial aneurysm presenting as cerebral circulation insufficiency:A case report

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World Journal of Clinical Cases 2021年第22期9卷 6380-6387页

作者： Long zhao Shuang-quan zhao Xiao-Ping Tang Department of Neurosurgery The Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Emergency Medicine The Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

BACKGROUND Rupture of an intracranial aneurysm is a type of acute stroke that is a serious threat to human *** of ruptured intracranial aneurysms is a serious clinical event that may have disastrous consequences in some *** date,ruptured intracranial aneurysms have been misdiagnosed as meningitis,tumors,stroke,or trauma,among other ***,we report what appears to be the first case of a ruptured intracranial aneurysm that presented as cerebral circulation *** SUMMARY A middle-aged man was admitted to our hospital because of a parasellar lesion identified on a noncontrast computed tomography(CT)image after a mild traffic accident that was caused by a brief loss of ***,he was diagnosed with cerebral circulation insufficiency after two unexplained episodes of a transient loss of consciousness within the past 8 *** patient was diagnosed with right internal carotid artery aneurysm based on CT angiography and completely recovered after a craniotomy at our hospital.A few clots and severe adhesions around the aneurysm were observed in the subarachnoid space during the operation,suggesting that the aneurysm had ruptured and may had been misdiagnosed as cerebral circulation *** Ruptured intracranial aneurysms may show negative imaging results and present as cerebral circulation insufficiency,which should be recognized as soon as possible to ensure timely management.

关键词： Intracranial aneurysm Misdiagnosis Cerebral circulation insufficiency Case

Model-Free Adaptive Frequency Calibration for Voltage-Controlled Oscillators

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China Communications 2023年第1期20卷 199-208页

作者： Lianghui Xie Zhi quan Osama Elnaha Qinglin zhao Faculty of Information Technology Macao University of Science and TechnologyMacao 999078China College of Electronic Information Engineering Shenzhen UniversityShenzhen 518060China Department of Electrical Engineering Faculty of EngineeringAssiut UniversityEgypt

The operating frequency accuracy of the local oscillators is critical for the overall system performance in the communication ***,the high-precision oscillators could be too expensive for civil *** this paper,we propose a model-free adaptive frequency calibration framework for a voltage-controlled crystal oscillator(VCO)equipped with a time to digital converter(TDC),which can significantly improve the frequency accuracy of the VCO thus *** idea is to utilize a high-precision TDC to directly measure the VCO period which is then passed to a model-free method for working frequency *** advantage of this method is that the working frequency calibration employs the system history of input/output(I/O)data,instead of establishing an accurate VCO voltagecontrolled oscillator *** advantage is the lightweight calibration method with low complexity such that it can be implemented on an MCU with limited computation *** results show that the proposed calibration method can improve the frequency accuracy of a VCO from±20 ppm to±10 ppb,which indicates the promise of the modelfree adaptive frequency calibrator for VCOs.

关键词： frequency calibration carrier frequency offset model-free adaptive control wireless communication systems

Changes in vegetation and moisture in the northern Tianshan of China over the past 450 years

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Frontiers of Earth Science 2020年第2期14卷 479-491页

作者： Weihe REN Yan zhao quan LI Jianhui CHEN Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of West China’s Environmental System(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

Knowledge of historical changes in moisture within semi-arid and arid regions is the basis of climatic change predictions and strategies in response to long-term *** this study,a multiproxy peat record with highresolution from Sichanghu in the northern Tianshan was used to document the changes in vegetation and climate over the past 450 years in the arid Central *** pollen,grain size,and loss on ignition(LOI)records indicate that the productivity of local peat began to increase at^1730 *** vegetation in the Sichanghu area experienced several transitions,from temperate desert to dense desert,marsh meadow,and steppe desert *** climate in the study area was extremely dry during the early stages of the Little Ice Age(LIA)(before 1730 AD)and relatively wet during the late stages(1730–1880 AD).The inferred changes in the moisture conditions of the Sichanghu peatland since the LIA may have been controlled by the extent of Arctic sea ice,the North Atlantic Oscillation,and the Siberian High via the connections of large-scale atmospheric circulations such as the Westerlies.

关键词： Little Ice Age pollen vegetation change moisture condition Tianshan arid Central Asia

Disinfection byproduct precursor removal by enhanced coagulation and their distribution in chemical fractions

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Journal of Environmental Sciences 2013年第11期25卷 2207-2213页

作者： Yanmei zhao Feng Xiao Dongsheng Wang Mingquan Yan Zhe bi Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Department of Environmental Engineering Peking University

Raw water from the Songhua River was treated by four types of coagulants, ferric chloride （FeC13）, aluminum sulfate （A12（504）3）, polyaluminum chloride （PACl） and composite polyaluminum （HPAC）, in order to remove dissolved organic matter （DOM）. Considering the disinfection byproduct （DBP） precursor treatability, DOM was divided into five chemical fractions based on resin adsorption. Trihalomethane formation potential （THMFP） and haloacetic acid formation potential （HAAFP） were measured for each fraction. The results showed that hydrophobic acids （HoA）, hydrophilic matter （HIM） and hydrophobic neutral （HoN） were the dominant fractions. Although both HoN and HoA were the main THM precursors, the contribution for THMFP changed after coagulation. Additionally, HoA and HiM were the main HAA precursors, while the contribution of HoN to HAAFP significantly increased after coagulation. HoM was more easily removed than HiM, no matter which coagulant was used, especially under enhanced coagulation conditions. DOC removal was highest for enhanced coagulation using FeCl3 while DBPFP was lowest using PAC1. This could indicate that not all DOC fractions contained the precursors of DBPs. Reduction of THMFP and HAAFP by PAC1 under enhanced coagulation could reach 51% and 59% respectively.

关键词： trihalomethanes haloacetic acids dissolved organic matter chemical fractionation enhanced coagulation

On infinite arithmetic progressions in sumsets

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Science China Mathematics 2023年第12期66卷 2669-2682页

作者： Yong-Gao Chen quan-Hui Yang Lilu zhao School of Mathematical Sciences and Institute of Mathematics Nanjing Normal UniversityNanjing 210023China School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China School of Mathematics Shandong UniversityJinan 250100China

Let k be a positive *** by D_(1/k)the least integer d such that for every set A of nonnegative integers with the lower density 1/k,the set(k+1)A contains an infinite arithmetic progression with difference at most d,where(k+1)A is the set of all sums of k+1 elements(not necessarily distinct)of *** and Li(2019)conjectured that D_(1/k)=k~2+o(k~2).The purpose of this paper is to confirm the above *** also prove that D_(1/k)is a prime for all sufficiently large integers k.

关键词： infinite arithmetic progressions sumsets primes circle method

Synthesis of hierarchical shell-core SnO2 microspheres and their gas sensing properties

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Chinese Chemical Letters 2020年第8期31卷 2083-2086页

作者： Li Zheng Wenjie bi zhao Jin Shantang Liu Key Lab for Green Chemical Process of Ministry of Education School of Chemistry and Environmental EngineeringWuhan Institute of TechnologyWuhan 430073China

Using SnSO4,D-glucose,urea and water,hierarchical shell-core SnO2 microspheres were successfully synthesized via a simple hydrothermal *** characte rization results showed that the sizes of asprepared SnO2 microspheres were 0,6-1μm,with shell thicknesses of 4060 nm,The shell and large core of the SnO2 microspheres were all comprised of the same basic rice-like nanoparticles with diameters of 16-25 nm and lengths of 16-45 *** investigaton showed that the glucose and urea served as structural guiding agents,and urea facilitated the formation of the hierarchical *** as-prepared SnO2 nanomaterials were used to fabricate a gas sensor with an electrode blade used for the gas sensitivity tests,The hierarchical shell-core SnO2 microspheres exhibited high sensitivity and selectivity toward ethanol,with a responsivity of 63.8 for 50 ppm ethanol at 250℃,while the response and recovery time were 7 s and 28 s,***,the responsivity of the materials showed good linearity at ethanol concentrations from 500 ppb to 10 *** simple synthetic method,environmentally-friendly raw materials,and excellent gas sensitivity demonstrate that the as-prepared SnO2 nanomaterial has great potential applications for the sensing of ethanol gas.

关键词： SnO2 microspheres Hydrothermal Shell-core Hierarchical Glucose Urea

Obstacle avoidance under relative localization uncertainty

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Science China(Information Sciences) 2019年第8期62卷 192-194页

作者： Yang LYU quan PAN Jinwen HU Chunhui zhao Key Laboratory of Information Fusion Technology Ministry of Education School of AutomationNorthwestern Polytechnical University

Dear editor,Collision avoidance is one of the classical topics in robotics research. Collision avoidance control is guided by implementing typical collision avoidance methods, such as potential field [1], dynamic programming [2], and geometrical calculation [3],to various platforms. Since these methods usually assume the perfect localization of an obstacle, they may not guarantee collision-free operations during

关键词： pro Obstacle avoidance under relative localization uncertainty

Synthesis and characterization of copolymers of poly(m-xylylene adipamide) and poly(ethylene terephthalate) oligomers by melt copolycondensation

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Chinese Journal of Chemical Engineering 2016年第9期24卷 1290-1297页

作者： Fenglei bi Jianqiang Shao Zhenhao Xi Ling zhao Di Liu Shanghai Key Laboratory of Multiphase Materials Chemical Engineering East China University of Science and Technology Beijing Sanlian Hope Shin-Gosen Technical Service Co. Ltd.

Poly（m-xylylene adipamide）/poly（ethylene terephthalate）（MXD6/PET） copolymers are synthesized by melt copolycondensation with 1–5 wt% low molecular weight PET oligomers into the MXD6 oligomers at 260 ℃.FR-IR and1 H NMR analysis results indicate that the interchange reaction has occurred between MXD6 oligomers and PET oligomers. The thermal behavior of copolymers shows that the melting temperature of MXD6/PET copolymers decreases with the increasing of amount of PET oligomers, while the crystallization temperature accordingly increases. And the equilibrium temperature Tm0 is evaluated to be 251.8 ℃ for the copolymers with5 wt% PET oligomer adding, which is very close to that of neat MXD6. The tensile and impact strength of MXD6/PET copolymers are significantly improved than that of pure MXD6 by mechanical properties test, and the microfibril structure in the impact fracture sample＇s surface reveals the feature of ductile fracture.

关键词： Polymerization Poly(m-xylylene adipamide) Poly(ethylene terephthalate) Crystallization Mechanical properties

quantum quenches in the Dicke model:Thermalization and failure of the generalized Gibbs ensemble

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Chinese Physics B 2020年第12期29卷 198-204页

作者： Xiao-Qiang Su You-quan zhao College of Physics and Information Engineering ShanXi Normal UniversityLinfen 041004China

quantum quenches in the Dicke model were studied both in the thermodynamic limit and the finite *** the integrable situation in the thermodynamic limit,the generalized Gibbs ensemble can effectively describe the energylevel occupations for the quench within the normal phase,but it fails for the quench to the superradiant *** the finite systems which are considered non-integrable,the post quench systems were studied by comparing with the thermal *** canonical ensembles are directly available for the quench within the normal *** the increasing of the target coupling strength over the equilibrium phase transition critical point,sudden changes take place for the effective temperature and the distance to the thermal *** thermalization was also studied by comparing with the results of the microcanonical ensembles.

关键词： quantum quench generalized Gibbs ensemble thermalization Dicke model