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Abnormal volumetric brain morphometry and cerebral blood flow in adolescents with depression

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World Journal of Psychiatry 2023年第6期13卷 386-396页

作者： yu-Jia Fu Xiao Liu Xing-yu Wang Xiao Li Lin-Qi Dai wen-yu ren Yong-Ming Zeng Zhen-Lin Li ren-Qiang yu Department of Radiology the First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Psychiatry the First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Radiology Chongqing HongRen Yi HospitalChongqing 408400China Department of Radiology West China HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural ***,preliminary studies have documented the pathophysiological changes in certain brain regions,such as the cerebellum,highlighting a need for further research to support the current understanding of this *** To study brain changes in depressed *** This study enrolled 34 adolescents with depression and 34 age-,sex-,and education-level-matched healthy control(HC)*** and functional alterations were identified when comparing the brains of these two participant groups through voxel-based morphometry and cerebral blood flow(CBF)analysis,*** between identified brain alterations and the severity of depressive symptoms were explored through Pearson correlation *** The cerebellum,superior frontal gyrus,cingulate gyrus,pallidum,middle frontal gyrus,angular gyrus,thalamus,precentral gyrus,inferior temporal gyrus,superior temporal gyrus,inferior frontal gyrus,and supplementary motor areas of adolescents with depression showed an increase in brain volume compared to HC *** patients with depression further presented with a pronounced drop in CBF in the left pallidum(group=98,and peak t=-4.4324),together with increased CBF in the right percental gyrus(PerCG)(group=90,and peak t=4.5382).In addition,17-item Hamilton Depression Rating Scale scores were significantly correlated with the increased volume in the opercular portion of the left inferior frontal gyrus(r=-0.5231,P<0.01).CONCLUSION The right PerCG showed structural and CBF changes,indicating that research on this part of the brain could offer insight into the pathophysiological causes of impaired cognition.

关键词： Voxel-based morphometry Cerebral blood flow Arterial spin labeling Adolescent Depression The right percental gyrus

Resting-state functional magnetic resonance imaging and support vector machines for the diagnosis of major depressive disorder in adolescents

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World Journal of Psychiatry 2024年第11期14卷 1696-1707页

作者： Zhi-Hui yu ren-Qiang yu Xing-yu Wang wen-yu ren Xiao-Qin Zhang Wei Wu Xiao Li Lin-Qi Dai Ya-Lan Lv Department of Radiology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Psychiatry The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China School of Medical Informatics Chongqing Medical UniversityChongqing 400016China

BACKGROUND Research has found that the amygdala plays a significant role in underlying pathology of major depressive disorder(MDD).However,few studies have explored machine learning-assisted diagnostic biomarkers based on amygdala functional connectivity(FC).AIM To investigate the analysis of neuroimaging biomarkers as a streamlined approach for the diagnosis of MDD in *** Forty-four adolescents diagnosed with MDD and 43 healthy controls were enrolled in the *** resting-state functional magnetic resonance imaging,the FC was compared between the adolescents with MDD and the healthy controls,with the bilateral amygdala serving as the seed point,followed by statistical analysis of the *** support vector machine(SVM)method was then applied to classify functional connections in various brain regions and to evaluate the neurophysiological characteristics associated with *** Compared to the controls and using the bilateral amygdala as the region of interest,patients with MDD showed significantly lower FC values in the left inferior temporal gyrus,bilateral calcarine,right lingual gyrus,and left superior occipital ***,there was an increase in the FC value in *** SVM analysis revealed that the reduction in the FC value in the right lingual gyrus could effectively differentiate patients with MDD from healthy controls,achieving a diagnostic accuracy of 83.91%,sensitivity of 79.55%,specificity of 88.37%,and an area under the curve of 67.65%.CONCLUSION The results showed that an abnormal FC value in the right lingual gyrus was effective as a neuroimaging biomarker to distinguish patients with MDD from healthy controls.

关键词： Major depressive disorder Adolescent Support vector machine Machine learning Resting-state functional magnetic resonance imaging Neuroimaging Biomarker

Future development research of 5G positioning in 3GPP standards

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： Liu wen ren Hailong Deng Zhongliang School of Electronic Engineering， Beijing University of Posts and Telecommunications

Since the release of the first version of the 5th Generation Mobile Networks (5G) standard， Release-15 (Rel-15)， in June 2018， the 3rd Generation Partnership Project (3GPP) made significant efforts in the field of indoor and outdoor wireless positioning. Notably， Release-16 augmented support for enhanced mobile broadband (eMBB) and ultra-reliable low-latency communication (uRLLC)， particularly within complex indoor settings. To further meet the diverse application needs of positioning scenarios， the 3GPP standards for Release-17 and Release-18 propose new enhancement measures to continuously provide more accurate positioning services. In this paper， the scholarly discourse on 5G positioning was critically examined， providing a systematic review of the 5G positioning standards as delineated in 3GPP's Release-16 and Release-17， and was extended the discussion to the anticipated enhancements in 5G Release-18， along with their underlying motivations. Through these discussions， this article not only a comprehensive perspective on the current development of 5G positioning technology was provided but also was offered forward-looking analysis and predictions for the evolution of positioning technology in the upcoming 3GPP Release-19 phase. Additionally， it serves as a reference for researchers interested in understanding the development of positioning within the standard framework in the field of 5G indoor positioning， which holds significant meaning for promoting research and application of 5G positioning technology.

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Thermoresponsive helical dendronized poly(arylacetylene)s:modulating the dynamic chirality

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Science China Chemistry 2025年

作者： Xueting Lu Lei Wang Liangxuan ren wen Li Afang Zhang International Joint Laboratory of Biomimetic&Smart Polymers School of Materials Science and EngineeringShanghai University

Helical poly(arylacetylene)s have formed an intriguing class of polymers,whose chiralities are dynamic and liable to external *** combining dendronized polymer topology with dendritic oligoethylene glycols (OEGs),we here report on synthesis of a homologous series of thermoresponsive dendronized poly(arylacetylene)s with either poly(phenyl acetylene) or poly(naphthalene acetylene) as the backbones,and investigate tunability of their helical *** polymers carry dendritic OEG pendants with either methoxyl-or ethoxyl-terminals to tune their unprecedent thermoresponsive behaviors,and at the same time,dendritic shielding plays an important role in mediating their thermal phase transition *** of these polymers is originated from the chiral alanine or phenylalanine moieties within the dendritic pendants,which can be tailored through manipulating solvation in different organic solvents or via thermal dehydration and collapse in ***,achiral additives such as linear or dendritic OEGs and benzene derivatives can act similarly as thermal dehydration to induce chirality transitions of these polymers in aqueous phase through interplay competitions between the additives and the polymers against their hydration.

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Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： Haonan Zhang Cheng Hao Tongtong Fu Dian yu Jane Howe Kaiwen Chen Ning Yan Hao ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons

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Earth and Planetary Physics 2025年第1期9卷 159-170页

作者： AoJun ren Jiang yu Jing Wang ZuZheng Chen XiaoMan Liu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519000China

Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric *** quantitative analyses often simplified the chorus dispersion relation by using the cold plasma ***,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic *** here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to *** statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma *** region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density *** addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus *** with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those ***,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.

关键词： chorus waves cold plasma approximation dispersion relations scattering rates

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基于LFM波形的极化雷达移频干扰鉴别

中国电子科学研究院学报 2017年第1期12卷 78-84页

作者：王文光季彧任欣北京航空航天大学电子信息工程学院北京100191 国睿科技有限公司江苏南京211106

基于数字射频存储器(Digital Ratio Frequency Memory,DRFM)的移频干扰是一种常见的针对线性调频(Linear Frequency Modulated,LFM)脉冲雷达系统的欺骗式干扰。由于LFM脉冲信号的模糊函数具有距离-多普勒耦合的特点,经移频处理后的干扰... 详细信息

基于数字射频存储器(Digital Ratio Frequency Memory,DRFM)的移频干扰是一种常见的针对线性调频(Linear Frequency Modulated,LFM)脉冲雷达系统的欺骗式干扰。由于LFM脉冲信号的模糊函数具有距离-多普勒耦合的特点,经移频处理后的干扰信号会对雷达接收系统产生距离欺骗的效果,常规雷达对抗移频干扰面临很多困难。该文研究了基于正负调频的LFM波形进行移频干扰鉴别的方法。通过全极化雷达的信号处理,真实目标和移频干扰会表现出差异,该文在正负调频LFM信号处理的基础上,构造了能够表现目标散射矩阵和干扰极化状态差异的特征量,该特征可以用于目标的真假鉴别。该文在给出鉴别量推导过程的同时,利用仿真数据对所提出的针对移频干扰的目标鉴别方法进行了验证,实验结果表明新的极化鉴别方法可以有效区分目标和移频干扰。

关键词：抗干扰移频干扰极化鉴别

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG Ping GUAN Chi ZHANG Jiahao ren School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

Shh和Ptch在结肠癌、腺瘤性息肉中的表达及意义

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海南医学院学报 2011年第5期17卷 600-603页

作者：张平喻文人重庆市荣昌县人民医院消化内科重庆402460

目的:检测Shh和Ptch蛋白在结肠癌、腺瘤性息肉中的表达,探讨二者在结肠癌发生、发展的作用,关注其在不同临床病理特征中的表达差别,为临床工作提供理论支持。方法:以80例大肠癌、80例结肠腺瘤性息肉、80例正常结肠黏膜组织作为研究对象... 详细信息

目的:检测Shh和Ptch蛋白在结肠癌、腺瘤性息肉中的表达,探讨二者在结肠癌发生、发展的作用,关注其在不同临床病理特征中的表达差别,为临床工作提供理论支持。方法:以80例大肠癌、80例结肠腺瘤性息肉、80例正常结肠黏膜组织作为研究对象,采用免疫组织化学技术,检测Shh和Ptch蛋白的表达,比较二者在不同临床指标及临床病理特征之间的关系。结果:Shh和Ptch蛋白在正常结肠黏膜组织、腺瘤性息肉、结肠癌中高的表达依次增高,Shh和Ptch在结肠癌中的表达与其肿瘤的有无炎细胞浸润、分化程度、Dukes分期及淋巴结转移密切相关,结肠癌中Shh和Ptch的表达呈正相关。结论:Shh和Ptch蛋白在结肠癌中高表达,显示二者在结肠癌的发生、发展中起协同作用,联合检测结肠癌中Shh和Ptch蛋白的表达可能与患者的预后相关。

关键词：结肠癌 Shh Ptch 免疫组织化学