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APPLICATION VALUE OF MAGNETIC RESONANCE SEQUENCES IN DIAGNOSIS OF EARLY SPINAL METASTATIC TUMOR

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Chinese Medical Sciences Journal 2007年第1期22卷 9-12页

作者： Li-xia Wang Xiang-quan Kong He-shui shi Ding-xi liu Yin Xiong Department of Radiology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022

Objective To investigate the clinical value of different magnetic resonance (MR) pulse sequences in diagnosis of spinal metastatic tumor. Methods Fifteen patients with clinically suspected spinal metastatic tumor were included in this study. These patients were with documented primary tumors. Four MR pulse sequences, T1-weighted spin echo (T1WI SE), T2-weighted fast spin echo (T2WI FSE), short time inversion recovery (STIR), and gradient echo 2-D multi echo data imaging combination (GE Me-2D) were used to detect spinal metastasis. Results Fifteen vertebral bodies were entire involvement, 38 vertebral bodies were section involvement, and totally 53 vertebral bodies were involved. There were 19 focal infections in pedicle of vertebral arch, 15 metastases in spinous process and transverse process. Fifty-three vertebral bodies were abnormal in T1WI SE and GE Me-2D, 35 vertebral bodies were found abnormal in T2WI FSE, and 50 vertebral bodies were found abnormal in STIR. The verges of focal signal of involved vertebral bodies were comparatively clear in T1WI SE, comparatively clear or vague in T2WI FSE, vague in STIR, and clear in GE *** GE Me-2D may be the most sensitive technique to detect metastases. So three sequences (T1WI SE, T2WI FSE, GE Me-2D) can demonstrate the early changes of spinal metastasis roundly.

关键词： spinal metastatic tumor T1-weighted spin echo T2-weighted fast spin echo gradient echo 2-D multi echo data imaging combination

Interference mechanism of trailing edge flap shedding vortices with rotor wake and aerodynamic characteristics

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Chinese Journal of Aeronautics 2025年第1期38卷 325-339页

作者： Yang liu Yongjie shi Aqib AZIZ Guohua XU Haifeng GAO National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A robust Reynolds-Averaged Navier-Stokes(RANS)based solver is established to predict the complex unsteady aerodynamic characteristics of the Active Flap Control(AFC)*** complex motion with multiple degrees of freedom of the Trailing Edge Flap(TEF)is analyzed by employing an inverse nested overset grid *** of non-rotational and rotational modes of blade motion are carried out to investigate the formation and development of TEF shedding vortex with high-frequency deflection of ***,the mechanism of TEF deflection interference with blade tip vortex and overall rotor aerodynamics is also *** nonrotational mode,two bundles of vortices form at the gap ends of TEF and the main blade and merge into a single TEF *** deflection of the TEF significantly interferes with the blade tip *** position of the blade tip vortex consistently changes,and its frequency is directly related to the frequency of TEF *** rotational mode,the tip vortex forms a helical *** end vortices at the gap sides co-swirl and subsequently merge into the concentrated beam of tip vortices,causing fluctuations in the vorticity and axial position of the tip vortex under the *** research concludes with the investigation on suppression of Blade Vortex Interaction(BVI),showing an increase in miss distance and reduction in the vorticity of tip vortex through TEF phase control at a particular control *** this mechanism,a designed TEF deflection law increases the miss distance by 34.7%and reduces vorticity by 11.9%at the target position,demonstrating the effectiveness of AFC in mitigating BVI.

关键词： CFD Rotor Aerodynamic Trailing edge flap Vortex shedding BVI

An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai liu Zhe Wang MengXi shi Willie Soon shiCan Qiu Department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA Institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

Molecular characteristics of dissolved organic phosphorus in watershed runoff:Coupled influences of land use and precipitation

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Journal of Environmental Sciences 2025年第2期148卷 387-398页

作者： Zhanyao shi Yao Du Hongni liu Yamin Deng Yiqun Gan Xianjun Xie State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution China University of GeosciencesWuhan 430078China Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science China University of GeosciencesWuhan 430078China School of Environmental Studies&State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China

Land use and precipitation are two major factors affecting phosphorus(P)pollution of watershed ***,molecular characterization of dissolved organic phosphorus(DOP)in runoff under the joint influences of land use and precipitation remains *** study used Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS)to study the molecular characteristics of DOP in a typical P-polluted watershed with spatially variable land use and *** results showed that low precipitation and intense human activity,including phosphate mining and associated industries,resulted in the accumulation of aliphatic DOP compounds in the upper reaches,characterized by low aromaticity and low biological *** precipitation and widespread agriculture in the middle and lower reaches resulted in highly unsaturated DOP compounds with high biological stability constituting a higher proportion,compared to in the upper ***,under similar precipitation,more aliphatic DOP compounds characterized by lower aromaticity and higher saturation were enriched in the lower reaches due to more influence from urban runoff relative to the middle *** and/or microbial processes did result in changes in the characteristics of DOP compounds during runoff processes due to the prevalence of low molecular weight and low O/C bioavailable aliphatic DOP molecules in the upper reaches,which were increasingly transformed into refractory compounds from the upper tomiddle *** results of this study can increase the understanding of the joint impacts of land use and precipitation on DOP compounds in watershed runoff.

关键词： Watershed runoff DOP FT-ICR MS Land use Precipitation

Revealing and predicting the long-term biomechanical response of orthokeratology by developing a patient-specific computational model

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 152-164页

作者： Yifeng Li Zhuoran Yang Ziming Yan Huibin shi Zhanli liu Kaijie Wang Department of Engineering Mechanics School of Aerospace EngineeringTsinghua UniversityBeijing 100084China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology&Visual Sciences Key LabBeijing 100730China

Orthokeratology(OK)is widely used for effective myopia correction and ***,the incomplete understanding of its biomechanical mechanisms makes OK lens fitting rely heavily on clinician judgment,complicating accurate predictions of treatment *** this paper,we performed clinical experiments and numerical analysis to study corneal deformation modes and long-term changes in central corneal *** experiments were conducted on 194 Chinese myopic patients under OK treatment for 3 *** on the experimental data,a patient-specific computational biomechanical model for OK was established and ***,the anisotropic mechanical properties of the cornea were incorporated into the model to describe the significant difference between its shear modulus(29.5 kPa)and tensile modulus(768.4 kPa).Additionally,a viscohyperelastic material model with a prolonged corneal relaxation time of 5.6 h was developed to capture the long-term deformation *** results show that corneal thickness reduction in OK is primarily due to out-of-plane shear deformation,influenced by the cornea’s low shear *** the extended corneal relaxation time is crucial for predicting long-term biomechanical *** computational model effectively captures long-term changes in central corneal thickness,potentially improving OK lens fitting accuracy.

关键词： orthokeratology computational biomechanical model long-term viscoelasticity myopia correction

Solid-state reduction kinetics and mechanism of pre-oxidized vanadium-titanium magnetite concentrate

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Transactions of Nonferrous Metals Society of China 2014年第10期24卷 3372-3377页

作者：刘水石郭宇峰邱冠周姜涛陈凤中南大学资源加工与生物工程学院长沙410083

The solid-state reduction kinetics of pre-oxidized vanadium-titanium magnetite concentrate was studied. The phase and microstructure of the reduction product were characterized by XRD, SEM and EDS methods, based on which the mechanism of the solid-state reduction was investigated. The results showed that using coal as reductant at 950-1100 °C, the solid-state reduction of the pre-oxidized vanadium-titanium magnetite concentrate was controlled by interface chemical reaction and the apparent activation energy was 67.719 k J/mol. The mineral phase transformation during the reduction process can be described as follows： pre-oxidized vanadium-titanium magnetite concentrate → ulvospinel → ilmenite → Fe Ti2O5 →（FenTi1-n）Ti2O5. M3O5-type（M can be Fe, Ti, Mg, Mn, etc） solid solutions would be formed during the reduction process of the pre-oxidized vanadium-titanium magnetite concentrate at 1050 °C for 60 min. The poor reducibility of iron in M3O5 solid solutions is the main reason to limit the reduction property of pre-oxidized vanadium-titanium magnetite concentrate.

关键词： vanadium-titanium magnetite solid-state reduction reduction kinetics reduction process

Construction of attapulgite-based one-dimensional nanonetwork composites with corrosion resistance for high-efficiency microwave absorption

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 689-698页

作者： Kai Xu Qingqing Gao Shaoqi shi Pei liu Yinxu Ni Zhilei Hao Gaojie Xu Yan Fu Fenghua liu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Zhejiang Key Laboratory of Additive Manufacturing Materials Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201China Northwest Yongxin Coatings Limited Company Lanzhou 730046China

Exploring high-efficiency and broadband microwave absorption(MA)materials with corrosion resistance and low cost is ur-gently needed for wide practical ***,the natural porous attapulgite(ATP)nanorods embedded with TiO_(2)and polyaniline(PANI)nanoparticles are synthesized via heterogeneous precipitation and in-situ *** obtained PANI-TiO_(2)-ATP one-di-mensional(1D)nanostructures can intertwine into three-dimensional(3D)conductive network,which favors energy *** min-imum reflection loss(RL_(min))of the PANI-TiO_(2)-ATP coating(20wt%)reaches-49.36 dB at 9.53 GHz,and the effective absorption band-width(EAB)can reach 6.53 GHz with a thickness of 2.1 *** excellent MA properties are attributed to interfacial polarization,mul-tiple loss mechanisms,and good impedance matching induced by the synergistic effect of PANI-TiO_(2)nanoparticle shells and ATP *** addition,salt spray and Tafel polarization curve tests reveal that the PANI-TiO_(2)-ATP coating shows outstanding corrosion resist-ance *** study provides a low-cost and high-efficiency strategy for constructing 1D nanonetwork composites for MA and corrosion resistance applications using natural porous ATP nanorods as carriers.

关键词： microwave absorption corrosion resistance attapulgite TiO_(2) polyaniline

SlPGR5/SlPGRL1 pathway-dependent cyclic electron transport regulates photoprotection and chloroplast quality in tomato plants

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Horticultural Plant Journal 2025年第1期11卷 211-226页

作者： Xiaolong Yang Yumeng Zhang Ting liu Jiali shi Mingfang Qi Riyuan Chen Yufeng liu Tianlai Li College of Horticulture South China Agricultural UniversityGuangzhouGuangdong 510642China College of Horticulture Shenyang Agricultural UniversityShenyangLiaoning 110866China Jiuquan Academy of Agricultural Sciences JiuquanGansu 735099China

The essential photoprotective role of proton gradient regulation 5(PGR5)-dependent cyclic electron flow(CEF)has been reported in Arabidopsis,rice,and ***,its functional assessment has not been performed in tomato *** this study,we focused on elucidate the function of SlPGR5 and SlPGR5-like photosynthetic phenotype 1(PGRL1)in *** performed RNA interference and found that SlPGR5/SlPGRL1-suppressed transformants exhibited extremely low CO_(2)assimilation capacity,their photosystem I(PSI)and PSII were severely photoinhibited and chloroplasts were obviously *** SlPGR5/SlPGRL1-suppressed plants almost completely inhibited CEF and Y(ND),and PSII photoinhibition may be directly related to the inability to produce sufficient proton motive force to induce *** transgenic plants overexpressing SlPGR5 and SlPGRL1 driven by 35S promoter capable alleviate photoinhibition of plants under low night *** transcriptomic and proteomic analyses suggested that the nuclear gene transcription and turnover of chloroplast proteins,including the plastoglobule-related proteins,were closely related to SlPGR5/SlPGRL1 pathway dependent *** bridge relationship between CEF and chloroplast quality maintenance was a novel report to our *** conclusion,these results revealed the regulatory mechanism of the SlPGR5/SlPGRL1 pathway in photoprotection and maintenance of chloroplast function in tomato,which is crucial for reduce yield loss,especially under adverse environmental conditions.

关键词： Tomato Cyclic electron transport SlPGR5/SlPGRL1 Photoprotection Chloroplast quality Plastoglobulus

Single-cell technologies: current and near future

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Science China(Life Sciences) 2025年第1期68卷 1-4页

作者： Chenfei Wang Qi liu Xiaohui Fan Tieliu shi KeyLaboratory of Spine and Spinal CordInjury Repairand Regeneration Ministry of EducationOrthopedics DepartmentTongji HospitalBioinformatics DepartmentSchoolofLifeSciencesandTechnologyTongji UniversityShanghai 200082China Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji UniversityShanghai 200092China Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji UniversityShanghai 200082China Research Institute of Intelligent Computing Zhejiang LabHangzhou 311121China Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314103China Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China Key Laboratory of Advanced Theory and Application in Statistics and Data Science(MOE) School of StatisticsEast China Normal UniversityShanghai 200062China

Single-cell technologies enable the indepth exploration of multiple biological hierarchies at the scale of individual cells,which have deepened our knowledge of cellular diversity,tissue organization,and overall organism function(Sun et al.,2024).In 2009,single-cell RNA sequencing(scRNA-seq)was first developed as a powerful tool to dissect gene expression and uncover transcriptional *** the rapid advancement of technology,single-cell approaches have expanded to encompass other omics,such as genomics,epigenomics,proteomics,and ***,multimodal technologies including spatially resolved transcriptomics and clustered regularly interspaced short palindromic repeats(CRISPR)screening at the single-cell level further advanced our ability to comprehensively understand cellular ***-cell methods provide deeper insights into disease mechanisms across various conditions,including cancer,developmental disorders,and aging-associated *** this issue,we focus on topics related to single-cell methods,covering the following four aspects:(i)single-cell multi-omic sequencing technology;(ii)single-cell spatial technology;(iii)singlecell CRISPR screening technology;(iv)applications of single-cell technology.

关键词： expanded enable insight

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