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缓解期双相情感障碍Ⅰ型患者白质纤维结构异常的扩散张量成像研究

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放射学实践 2024年第4期39卷 455-460页

作者：林泰锋杜碧茵陈锦佳吴海珊肖叶玉陈俊浩广州医科大学附属脑科医院放射科广东广州510370 广州市中西医结合医院医学影像科广东广州510800

目的:探讨缓解期双相情感障碍(BD)Ⅰ型患者脑白质神经纤维束的改变,及患者认知功能与脑白质病变的关系。方法:采用汉密尔顿抑郁量表(HAMD),杨氏躁狂量表(YMRS)和重复性成套神经心理状态量表(RBANS)对患者进行入组的筛查与认知评估。应用... 详细信息

目的:探讨缓解期双相情感障碍(BD)Ⅰ型患者脑白质神经纤维束的改变,及患者认知功能与脑白质病变的关系。方法:采用汉密尔顿抑郁量表(HAMD),杨氏躁狂量表(YMRS)和重复性成套神经心理状态量表(RBANS)对患者进行入组的筛查与认知评估。应用3.0T磁共振仪对76例缓解期BD-Ⅰ型患者以及66例年龄、性别相匹配的健康志愿者(对照组)行DTI扫描,使用PANDA软件包提取全脑白质纤维束的各向异性分数(FA)和平均扩散率(MD),采用独立样本t检验进行组间差异比较,及Pearson相关分析探讨BD组中各纤维束的FA与临床可重复神经心理状态测验(RBANS)评分间的相关性。结果:相较于对照组,BD-Ⅰ型组的左、右侧钩束、右侧上纵束、右侧下额枕束及左侧毯束的FA值降低,MD值升高,差异均具有统计学意义(P<0.01)。BD-Ⅰ型组的左、右侧钩束、右侧上纵束和右侧下额枕束的FA值与RBANS量表评估的总分及即刻记忆、延迟记忆、视觉广度和注意力四项因子的评分均具有正相关关系(r=0.32~0.44,P均<0.05)。结论:缓解期双相障碍BD I型患者多个脑白质神经纤维束微观结构受损,且与认知功能改变相关。

关键词：双相情感障碍扩散张量成像脑白质神经纤维束

Pulse signal detection in cognitive UWB system

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 74-79页

作者： SONG Xiao-ou XIANG Xin bi du-yan DENG Yong Engineering College Air Force Engineering.UniversityXi'an 710038China

According to the problem of cognitive ultra wide-band （UWB） spectrum sensing, a novel UWB pulse signal detection algorithm based on cumulative sum （CUSUM） test is proposed in this paper. Based on the analysis of the existing spectrum sensing schemes for cognitive UWB system, some obvious facts are obtained that it is difficult to detect UWB pulse signal with conventional spectrum sensing schemes, due to its low average signal to noise ratio （SNR）, large bandwidth, and low duty ratio. In this paper the detection algorithm of signal distribution change, which is application of CUSUM test, is considered to be applied to cognitive UWB spectrum sensing. But CUSUM test request that the pre-change and the post-change distributions are i.i.d, which cannot be satisfied in the detection process of UWB pulse signal. Since there are two time domain descriptions on UWB pulse signal, namely one contains only noise and the other one contains pulse signal plus noise, the existing detection algorithm of signal distribution change cannot be directly applied to detect UWB pulse signal. Hence the uniform probability density function expression of UWB pulse signal is first deduced, then CUSUM test is applied to cognitive UWB spectrum sensing. The proposed algorithm is a time sequential detection algorithm, with low complexity and minimal detection delay, which is suitable to detect the low duty ratio signal. Its performance is evaluated through theoretical analysis and numerical simulations. It is shown that this algorithm outperforms the conventional energy detection algorithm and conquers SNR wall phenomenon.

关键词： cognitive UWB (CUWB) spectrum sensing pulse signal CUSUM

Rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method

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World Journal of Gastroenterology 2009年第20期15卷 2537-2542页

作者： Jian-Ming Xing Su Zhang Ying du Dan bi Li-Hui Yao Huzhou Maternity and Child Care Hospital Huzhou 313000 Zheiiang Province China

AIM:To develop a new, rapid and accurate reverse dot blot(RDB) method for the detection of intestinal pathogens in fecal ***:The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum , Bacillus cereus , Clostridium perfringens , Vibrio parahaemolyticus , Shigella spp., Yersinia enterocolitica, Vibrio cholerae, Listeria monocytogenes and Staphylococcus *** two universal primers were designed to amplify two variable regions of bacterial 16S and 23S rDNA genes from all of the 12 bacterial species *** hundred and forty fecal samples from the diarrhea patients were detected using the improved RDB ***:The methods could identify the 12 intestinal pathogens specifi cally, and the detection limit was as low as 103 *** consistent detection rate of the improved RDB assay compared with the traditional culture method was up to 88.75%.CONCLUSION:The hybridization results indicated that the improved RDB assay developed was a reliable method for the detection of intestinal pathogen in fecal samples.

关键词： Immunoblotting Intestinal pathogens Feces

Effects of surface cracks on the rhizospheric microhabitat of Artemisia ordosica in subsidence area caused by coal mining

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Journal of Coal Science & Engineering(China) 2013年第2期19卷 231-236页

作者： Tao du Yin-Li bi Fei GAO Wei-Ling LV School of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing) Beijing 100083China

The effects of surface cracks caused by underground coal mining on microhabitat in the rhizosphere of Artem＆ia ordosias were studied based on field investigation and sample analysis. The results show that the amounts of microorganisms, enzyme activity and water content in soil vary with the biomass ofA. ordosias, and that the account exhibits in an order of large A. ordosias〉medium A. ordosias〉small A. ordosias. Surface cracks apparently decrease microbial quantities and enzymatic ac- tivities, and change the composition and structure of microbial community in the rhizosphere of A. ordosias. Surface cracks reduce water content and electrical conductivity, enhance the R/S （ratio of root and soil） of water content, electrical conductivity and pH value, and raise the content of Na and Pb in rhizosphere soil ofA. ordosicas, It can be concluded that the disturbance of underground coal mining on the microhabitat in the rhizosphere ofA. ordosica is obvious in the early days.

关键词： rhizosphere microhabitat mining crack microbial quantity enzymatic activity Artemisia ordosica

Manipulating Nb-doped SrFeO_(3−δ)with excellent performance for proton-conducting solid oxide fuel cells

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Journal of Advanced Ceramics 2024年第5期13卷 579-589页

作者： Hailu Dai Hongzhe du Samir Boulfrad Shoufu Yu Lei bi Qinfang Zhang School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China College of Science&Engineering Hamad Bin Khalifa UniversityDoha 34110Qatar School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China

Nb-doped SrFeO_(3−δ)(SFO)is used as a cathode in proton-conducting solid oxide fuel cells(H-SOFCs).First-principles calculations show that the SrFe0.9Nb0.1O_(3−δ)(SFNO)cathode has a lower energy barrier in the cathode reaction for H-SOFCs than the Nb-free SrFeO_(3−δ)*** experimental studies show that Nb doping substantially enhances the performance of the SrFeO_(3−δ)***,oxygen vacancies(VO)were introduced into SFNO using the microwave sintering method,further improving the performance of the SFNO *** mechanism behind the performance improvement owing to VO was revealed using first-principles calculations,with further optimization of the SFNO cathode achieved by developing a suitable wet chemical synthesis route to prepare nanosized SFNO *** method significantly reduces the grain size of SFNO compared with the conventional solid-state reaction method,although the solid-state reaction method is generally used for preparing Nb-containing *** a result of defect engineering and synthesis approaches,the SFNO cathode achieved an attractive fuel cell performance,attaining an output of 1764 mW·cm−2 at 700℃ and operating for more than 200 *** manipulation of Nb-doped SrFeO_(3−δ)can be seen as a“one stone,two birds”strategy,enhancing cathode performance while retaining good stability,thus providing an interesting approach for constructing high-performance cathodes for H-SOFCs.

关键词： SrFeO_(3−δ)-(SFO) cathode proton conductor solid oxide fuel cells(SOFCs)

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高地应力特大断面隧道的适宜施工工法

科学技术与工程 2024年第20期24卷 8723-8732页

作者：王义乾刘远明田娇杜碧涛陈林全王忠星牙兰开贵州大学土木工程学院贵阳550025 贵州省岩土力学与工程安全重点实验室贵阳550025 贵州省交通规划勘察设计研究院股份有限公司贵阳550008

为探索高地应力特大断面软岩隧道的适宜施工方法,以桐梓隧道为工程背景,通过现场监测和数值模拟,探索不同高地应力下的3种施工工法[三台阶、CD(cross diaphragm)法、双侧壁导坑法]的适宜性,从围岩变形、施工成本以及施工进度等方面评价... 详细信息

为探索高地应力特大断面软岩隧道的适宜施工方法,以桐梓隧道为工程背景,通过现场监测和数值模拟,探索不同高地应力下的3种施工工法[三台阶、CD(cross diaphragm)法、双侧壁导坑法]的适宜性,从围岩变形、施工成本以及施工进度等方面评价施工方法的优劣。结果表明:Ⅴ级围岩:当隧道埋深为300、400 m时,适用三台阶法施工;当埋深为500 m时,适用CD法施工;当埋深为600 m时,适用双侧壁导坑法施工。Ⅳ级围岩:当隧道埋深为300~600 m时,都适用三台阶法施工。

关键词：高地应力隧道特大断面施工工法数值模拟适宜性

Effect of crystal morphology of ultrahigh-nickel cathode materials on high temperature electrochemical stability of lithium ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 327-335,I0008页

作者： bi Luo Hui Li Haoyu Qi Yun Liu Chuanbo Zheng Weitong du Jiafeng Zhang Lai Chen School of Metallurgy Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600JiangsuChina National Engineering Laboratory for High-Efficiency Recovery of Refractory Nonferrous Metals School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina School of Materials Science and Engineering Beijing Key Laboratory of Environmental Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Higher nickel content endows Ni-rich cathode materials LiNi_(x)Co_yMn_(1-x-y)O_(2)(x>0.6)with higher specific capacity and high energy density,which is regarded as the most promising cathode materials for Li-ion ***,the deterioration of structural stability hinders its practical application,especially under harsh working conditions such as high-temperature *** these circumstances,it becomes particularly critical to clarify the impact of the crystal morphology on the structure and high-temperature performance as for the ultrahigh-nickel ***,we conducted a comprehensive comparison in terms of microstructure,high-temperature long-cycle phase evolution,and high-temperature electrochemical stability,revealing the differences and the working mechanisms among polycrystalline(PC),single-crystalline(SC)and Al doped SC ultrahigh-nickel *** results show that the PC sample suffers a severe irreversible phase transition along with the appearance of microcracks,resulting a serious decay of both average voltage and the energy *** the Al doped SC sample exhibits superior cycling stability with intact layered ***-situ XRD and intraparticle structural evolution characterization reveal that Al doping can significantly alleviate the irreversible phase transition,thus inhibiting microcracks generation and enabling enhanced ***,it exhibits excellent cycling performance in pouch-type full-cell with a high capacity retention of 91.8%after 500 cycles at 55℃.This work promotes the fundamental understanding on the correlation between the crystalline morphology and high-temperature electrochemical stability and provides a guide for optimization the Ni-rich cathode materials.

关键词： Single-crystalline Ultrahigh-nickel cathode High-temperature performance Phase evolution

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交叉视觉皮质模型的格论分析

西安电子科技大学学报 2009年第6期36卷 1120-1125页

作者：高山毕笃彦空军工程大学工程学院陕西西安710038

从格论角度对有生物学背景的交叉视觉皮质模型(ICM)在图像处理中的脉冲并行传播特性进行了分析.格论中,图像为高维空间上的一个点集,ICM对图像的处理即找到一种映射关系,使点集变为偏序集.通过ICM对二值图像、灰度图像及彩色图像处理过... 详细信息

从格论角度对有生物学背景的交叉视觉皮质模型(ICM)在图像处理中的脉冲并行传播特性进行了分析.格论中,图像为高维空间上的一个点集,ICM对图像的处理即找到一种映射关系,使点集变为偏序集.通过ICM对二值图像、灰度图像及彩色图像处理过程的分析可以得到ICM进行图像处理时脉冲并行传播特性的格论基础,为具有生物学背景的ICM图像处理应用建立了数学依据.

关键词：格论交叉视觉皮质模型(ICM) 彩色图像矢量排序

Monitoring Xylem Transport in the Stem of Lilium lancifolium Using Fluorescent Dye 5(6)-Carboxyfluorescein Diacetate

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1057-1066页

作者： Yulin Luo Panpan Yang Mengmeng bi Leifeng Xu Fang du Jun Ming College of Horticulture Shanxi Agricultural UniversityJinzhong030801China State Key Laboratory of Vegetable biobreeding Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China College of Urban and Rural Construction Shanxi Agricultural UniversityJinzhong030801China

The xylem undergoes physiological changes in response to various environmental conditions during the process of plant *** understand these physiological changes,it is extremely important to observe the transport of *** this study,the distribution and structure of vascular bundle in Lilium lancifolium were observed using the method of semithin *** for introducing a fluorescent tracer into the xylem of the stems were ***,the transport rule of 5(6)-Carboxyfluorescein diacetate(CFDA)in the xylem of the stem of *** was studied by fluorescence dye in live cells tracer *** results showed that the vascular bundles of *** were scattered in the basic tissue,the peripheral vascular bundles were smaller and densely distributed,and the closer to the center,the larger the volume of vascular bundles and the more sparsely *** vascular bundles of *** are limited external tenacity vascular bundles,which are composed of phloem and *** most suitable method for CFDA labeling the xylem of isolated stem segments of *** was solution soaking for 24 *** running speed of CF in the isolated stem was 0.3 cm/h,which was consistent with the running speed of the material in the *** could be transported between the xylem and parenchyma cells,indicating that the material transport in the xylem could be through the symplastic *** above results laid a foundation for the study of the xylem transport mechanism and the xylem pathogen disease of lily.

关键词： Lilium xylem transport stem fluorescent dye CFDA