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Two-Dimensional Perovskite Single Crystals for High-Performance X-ray Imaging and Exploring MeV X-ray Detection 被引量:1
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作者 Xieming Xu Yiheng Wu +5 位作者 Yi Zhang Xiaohui Li Fang Wang Xiaoming Jiang Shaofan Wu Shuaihua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期139-146,共8页
Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection roles.Recently,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,bu... Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection roles.Recently,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,but they are mostly used in low-energy(≤130 keV)regions.Direct detection of MeV X-rays,which ensure thorough penetration of the thick shell walls of containers,trucks,and aircraft,is also highly desired in practical industrial applications.Unfortunately,scintillation semiconductors for high-energy X-ray detection are currently scarce.Here,This paper reports a 2D(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single crystal with outstanding sensitivity and stability toward X-ray radiation that provides an ultra-wide detectable X-ray range of between 8.20 nGy_(air)s^(-1)(50 keV)and 15.24 mGy_(air)s^(-1)(9 MeV).The(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single-crystal detector with a vertical structure is used for high-performance X-ray imaging,delivering a good spatial resolution of 4.3 Ip mm^(-1)in a plane-scan imaging system.Low ionic migration in the 2D perovskite enables the vertical device to be operated with hundreds of keV to MeV X-ray radiation at high bias voltages,leading to a sensitivity of 46.90μC Gy_(air)-1 cm^(-2)(-1.16 Vμm^(-1))with 9 MeV X-ray radiation,demonstrating that 2D perovskites have enormous potential for high-energy industrial applications. 展开更多
关键词 MeV X-ray detection single-crystal X-ray detectors two-dimensional perovskites X-ray imaging
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Modeling load distribution for rural photovoltaic grid areas using image recognition
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作者 Ning Zhou Bowen Shang +1 位作者 Jinshuai Zhang Mingming Xu 《Global Energy Interconnection》 EI CSCD 2024年第3期270-283,共14页
Expanding photovoltaic(PV)resources in rural-grid areas is an essential means to augment the share of solar energy in the energy landscape,aligning with the“carbon peaking and carbon neutrality”objectives.However,ru... Expanding photovoltaic(PV)resources in rural-grid areas is an essential means to augment the share of solar energy in the energy landscape,aligning with the“carbon peaking and carbon neutrality”objectives.However,rural power grids often lack digitalization;thus,the load distribution within these areas is not fully known.This hinders the calculation of the available PV capacity and deduction of node voltages.This study proposes a load-distribution modeling approach based on remote-sensing image recognition in pursuit of a scientific framework for developing distributed PV resources in rural grid areas.First,houses in remote-sensing images are accurately recognized using deep-learning techniques based on the YOLOv5 model.The distribution of the houses is then used to estimate the load distribution in the grid area.Next,equally spaced and clustered distribution models are used to adaptively determine the location of the nodes and load power in the distribution lines.Finally,by calculating the connectivity matrix of the nodes,a minimum spanning tree is extracted,the topology of the network is constructed,and the node parameters of the load-distribution model are calculated.The proposed scheme is implemented in a software package and its efficacy is demonstrated by analyzing typical remote-sensing images of rural grid areas.The results underscore the ability of the proposed approach to effectively discern the distribution-line structure and compute the node parameters,thereby offering vital support for determining PV access capability. 展开更多
关键词 Deep learning Remote sensing image recognition Photovoltaic development Load distribution modeling Power flow calculation
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Early prediction of myocardial viability after acute myocardial infarction by two-dimensional speckle tracking imaging 被引量:15
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作者 Jong Shin Woo Tae-Kyung Yu Woo-Shik Kim Kwon Sam Kim Weon Kim 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2015年第5期474-481,共8页
Background Identifying the transmural extent of myocardial necrosis and the degree of myocardial viability in acute myocardial infarction (AMI) is important clinically. The aim of this study was to assess myocardial... Background Identifying the transmural extent of myocardial necrosis and the degree of myocardial viability in acute myocardial infarction (AMI) is important clinically. The aim of this study was to assess myocardial viability using two-dimensional speckle tracking imaging (2D-STI) in patients with AMI. Methods 2D-STI was performed at initial presentation, three days, and six months after primary percutaneous coronary intervention (PCI) in 30 patients with AMI, who had a left anterior descending coronary artery (LAD) culprit lesion. In addition, 20 patients who had minimal stenotic lesions (〈 30% stenosis) on coronary angiography were also included in the control group. At six months dobutamine echocardiography was performed for viability assessment in seven segments of the LAD territory. According to the recovery of wall motion abnormality, segments were classified as viable or non-viable. Results A total of 131 segments were viable, and 44 were nonviable. Multivariate analysis revealed significant differences between the viable and nonviable segments in the peak systolic strain, the peak systolic strain rate at initial presentation, and peak systolic strain rate three days after primary PCI. Among these, the initial peak systolic strain rate had the highest predictive value for myocardial viability (hazard ratio: 31.22, P 〈 0.01). Conclusions 2D-STI is feasible for assessing myocardial viability, and the peak systolic strain rate might be the most reliable predictor of myocardial viability in patients with AMI. 展开更多
关键词 Acute myocardial infarction two-dimensional speckle tracking imaging Viable myocardium
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Proof-of-principle experimental demonstration of quantum secure imaging based on quantum key distribution 被引量:1
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作者 Yi-Bo Zhao Wan-Li Zhang +3 位作者 Dong Wang Xiao-Tian Song Liang-Jiang Zhou Chi-Biao Ding 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期332-337,共6页
We present a quantum secure imaging(QSI) scheme based on the phase encoding and weak+vacuum decoy-state BB84 protocol of quantum key distribution(QKD). It allows us to implement a computational ghost imaging(CGI) syst... We present a quantum secure imaging(QSI) scheme based on the phase encoding and weak+vacuum decoy-state BB84 protocol of quantum key distribution(QKD). It allows us to implement a computational ghost imaging(CGI) system with more simplified equipment and reconstructed algorithm by using a digital micro-mirror device(DMD) to preset the specific spatial distribution of the light intensity. What is more, the quantum bit error rate(QBER) and the secure key rate analytical functions of QKD are used to see through the intercept-resend jamming attacks and ensure the authenticity of the imaging information. In the experiment, we obtained the image of the object quickly and efficiently by measuring the signal photon counts with a single-photon detector(SPD), and achieved a secure key rate of 571.0 bps and a secure QBER of 3.99%, which is well below the lower bound of QBER of 14.51%. Besides, our imaging system uses a laser with invisible wavelength of 1550 nm, whose intensity is as low as single-photon, that can realize weak-light imaging and is immune to the stray light or air turbulence, thus it will become a better choice for quantum security radar against intercept-resend jamming attacks. 展开更多
关键词 QUANTUM SECURE imaging(QSI) QUANTUM key distribution(QKD) digital micro-mirror device(DMD) QUANTUM bit error rate(QBER)
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Near-infrared chemical imaging for quantitative analysis of chlorpheniramine maleate and distribution homogeneity assessment in pharmaceutical formulations 被引量:2
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作者 Manfei Xu Luwei Zhou +3 位作者 Qiao Zhang Zhisheng Wu Xinyuan Shi Yanjiang Qiao 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2016年第6期12-20,共9页
Near infrared chemical imaging(NIR-CI)combines conventional near infrared(NIR)spectros-copy with chemical imaging,thus provides spectral and spatial information simult aneously.It could be utilized to visualize the sp... Near infrared chemical imaging(NIR-CI)combines conventional near infrared(NIR)spectros-copy with chemical imaging,thus provides spectral and spatial information simult aneously.It could be utilized to visualize the spatial distribution of the ingredients in a sample.The data acquired using NIR CI instrument are hyperspectral data cube(hypercube)containing thousands of spectra.Chemometric methodologies are necessary to transform spectral information into chemical information.Partial least squares(PLS)method was performed to extract chemical information of chlorpheniramine maleate in pharmaceutical formulations.A series of samples which consisted of different CPM concentrations(w/w)were compressed and hypercube data were measured.The spectra extracted from the hypercube were used to establish the PLS model of CPM.The results of the model were R^(2)_(val)0.981,RMSEC 0.384%,RMSECV 0.483%,RMSEP 0.631%,indicating that this model was reliable. 展开更多
关键词 Near infrared chemical imaging partial least squares regression assessment of distributional homogeneity chlorpheniramine maleate
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Magnetic Particle Imaging for Magnetic Hyperthermia Treatment: Visualization and Quantification of the Intratumoral Distribution and Temporal Change of Magnetic Nanoparticles in Vivo 被引量:5
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作者 Tomomi Kuboyabu Isamu Yabata +4 位作者 Marina Aoki Natsuo Banura Kohei Nishimoto Atsushi Mimura Kenya Murase 《Open Journal of Medical Imaging》 2016年第1期1-15,共15页
Purpose: Magnetic hyperthermia treatment (MHT) is a strategy for cancer therapy using the tem-perature rise of magnetic nanoparticles (MNPs) under an alternating magnetic field (AMF). Re-cently, a new imaging method c... Purpose: Magnetic hyperthermia treatment (MHT) is a strategy for cancer therapy using the tem-perature rise of magnetic nanoparticles (MNPs) under an alternating magnetic field (AMF). Re-cently, a new imaging method called magnetic particle imaging (MPI) has been introduced. MPI allows imaging of the spatial distribution of MNPs. The purpose of this study was to investigate the feasibility of visualizing and quantifying the intratumoral distribution and temporal change of MNPs and predicting the therapeutic effect of MHT using MPI. Materials and Methods: Colon-26 cells (1 × 106 cells) were implanted into the backs of eight-week-old male BALB/c mice. When the tumor volume reached approximately 100 mm3, mice were divided into untreated (n = 10) and treated groups (n = 27). The tumors in the treated group were directly injected with MNPs (Resovist?) with iron concentrations of 500 mM (A, n = 9), 400 mM (B, n = 8), and 250 mM (C, n = 10), respectively, and MHT was performed using an AMF with a frequency of 600 kHz and a peak amplitude of 3.5 kA/m. The mice in the treated group were scanned using our MPI scanner immediately before, immediately after, 7 days, and 14 days after MHT. We drew a region of interest (ROI) on the tumor in the MPI image and calculated the average, maximum, and total MPI values and the number of pixels by taking the threshold value for extracting the contour as 40% of the maximum MPI value (pixel value) within the ROI. These parameters in the untreated group were taken as zero. We also measured the relative tumor volume growth (RTVG) defined by (V-V0)/V0, where V0 and V are the tumor volumes immediately before and after MHT, respectively. Results: The average, maximum, and total MPI values decreased up to 7 days after MHT and remained almost constant thereafter in all groups, whereas the number of pixels tended to increase with time. The RTVG values in Groups A and B were significantly lower than those in the control group 3 days or more and 5 days or more after MHT, respectively. The above four parameters were significantly inversely correlated with the RTVG values 5, 7, and 14 days after MHT. Conclusion: MPI can visualize and quantify the intratumoral distribution and temporal change of MNPs before and after MHT. Our results suggest that MPI will be useful for predicting the therapeutic effect of MHT and for the treatment planning of MHT. 展开更多
关键词 Magnetic Particle imaging Magnetic Hyperthermia Treatment Magnetic Nanoparticles Intratumoral distribution Temporal Change
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Real-Time Characterization of Crystal Shape and Size Distribution Based on Moving Window and 3D Imaging in a Stirred Tank 被引量:1
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作者 Rui Zhang Xuezhong Wang +1 位作者 Yang Zhang Tao Liu 《Journal of Crystallization Process and Technology》 2019年第2期13-38,共26页
Crystal shape distribution, i.e. the multidimensional size distribution of crystals, is of great importance to their down-stream processing such as in filtration as well as to the end-use properties including the diss... Crystal shape distribution, i.e. the multidimensional size distribution of crystals, is of great importance to their down-stream processing such as in filtration as well as to the end-use properties including the dissolution rate and bioavailability for crystalline pharmaceuticals. Engineering crystal shape and shape distribution requires knowledge about the growth behavior of different crystal facets under varied operational conditions e.g. supersaturations. Measurement of the facet growth rates and growth kinetics of static crystals in a crystallizer without stirring has been reported previously. Here attention is given to study on real-time characterization of the 3D facet growth behavior of crystals in a stirred tank where crystals are constantly moving and rotating. The measurement technique is stereo imaging and the crystal shape reconstruction is based on a stereo imaging camera model. By reference to a case study on potash alum crystallization, it is demonstrated that the crystal size and shape distributions (CSSD) of moving and rotating potash alum crystals in the solution can be reconstructed. The moving window approach was used to correlate 3D face growth kinetics with supersaturation (in the range 0.04 - 0.12) given by an ATR FTIR probe. It revealed that {100} is the fastest growing face, leading to a rapid reduction of its area, while the {111} face has the slowest growth rate, reflected in its area continuously getting larger. 展开更多
关键词 STEREO imaging Camera Model Crystal Size and Shape distribution 3D Reconstruction POTASH ALUM FACET Growth Kinetics
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Visibility enhancement in two-dimensional lensless ghost imaging with true thermal light
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作者 陈希浩 燕玲 +5 位作者 吴炜 孟少英 吴令安 孙志斌 王超 翟光杰 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期101-105,共5页
We report an experimental demonstration of two-dimensional(2D) lensless ghost imaging with true thermal light. An electrodeless discharge lamp with a higher light intensity than the hollow cathode lamp used before i... We report an experimental demonstration of two-dimensional(2D) lensless ghost imaging with true thermal light. An electrodeless discharge lamp with a higher light intensity than the hollow cathode lamp used before is employed as a light source. The main problem encountered by the 2D lensless ghost imaging with true thermal light is that its coherence time is much shorter than the resolution time of the detection system. To overcome this difficulty we derive a method based on the relationship between the true and measured values of the second-order optical intensity correlation, by which means the visibility of the ghost image can be dramatically enhanced. This method would also be suitable for ghost imaging with natural sunlight. 展开更多
关键词 ghost imaging true thermal light image visibility two-dimensional image
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Spatial distribution patterns of anorectal atresia/stenosis in China:Use of two-dimensional graph-theoretical clustering
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作者 Ping Yuan Liang Qiao +8 位作者 Li Dai Yan-Ping Wang Guang-Xuan Zhou Ying Han Xiao-Xia Liu Xun Zhang Yi Cao Juan Liang Jun Zhu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第22期2787-2793,共7页
AIM:To investigate the spatial distribution patterns of anorectal atresia/stenosis in China.METHODS:Data were collected from the Chinese Birth Defects Monitoring Network(CBDMN),a hospital-based congenital malformation... AIM:To investigate the spatial distribution patterns of anorectal atresia/stenosis in China.METHODS:Data were collected from the Chinese Birth Defects Monitoring Network(CBDMN),a hospital-based congenital malformations registry system.All fetuses more than 28 wk of gestation and neonates up to 7 d of age in hospitals within the monitoring sites of the CBDMN were monitored from 2001 to 2005.Two-dimensional graph-theoretical clustering was used to divide monitoring sites of the CBDMN into different clusters according to the average incidences of anorectal atresia/stenosis in the different monitoring sites.RESULTS:The overall average incidence of anorectal atresia/stenosis in China was 3.17 per 10000 from 2001 to 2005.The areas with the highest average incidences of anorectal atresia/stenosis were almost always focused in Eastern China.The monitoring sites were grouped into 6 clusters of areas.Cluster 1 comprised the monitoring sites in Heilongjiang Province,Jilin Province,and Liaoning Province;Cluster 2 was composed of those in Fujian Province,Guangdong Province,Hainan Province,Guangxi Zhuang Autonomous Region,south Hunan Province,and south Jiangxi Province;Cluster 3 consisted of those in Beijing Municipal City,Tianjin Municipal City,Hebei Province,Shandong Province,north Jiangsu Province,and north Anhui Province;Cluster 4 was made up of those in Zhejiang Province,Shanghai Municipal City,south Anhui Province,south Jiangsu Province,north Hunan Province,north Jiangxi Province,Hubei Province,Henan Province,Shanxi Province and Inner Mongolia Autonomous Region;Cluster 5 consisted of those in Ningxia Hui Autonomous Region,Gansu Province and Qinghai Province;and Cluster 6 included those in Shaanxi Province,Sichuan Province,Chongqing Municipal City,Yunnan Province,Guizhou Province,Xinjiang Uygur Autonomous Province and Tibet Autonomous Region.CONCLUSION:The fi ndings in this research allow the display of the spatial distribution patterns of anorectal atresia/stenosis in China.These will have important guiding significance for further analysis of relevant environmental factors regarding anorectal atresia/ stenosis and for achieving regional monitoring for anorectal atresia/stenosis. 展开更多
关键词 Spatial distribution Anorectal atresia/ stenosis two-dimensional graph-theoretical clustering Incidence Monitoring
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Observation of the Two-Dimensional Distribution of Impurity Line Emissions Using a Space-Resolved EUV Spectrometer in LHD
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作者 王二辉 S.MORITA +1 位作者 M.GOTO 董春凤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第2期106-109,共4页
A space-resolved EUV spectrometer for measuring the one-dimensional distribution of impurity line emissions in Large Helical Device (LHD) has been upgraded to measure two- dimensional distributions of impurity line ... A space-resolved EUV spectrometer for measuring the one-dimensional distribution of impurity line emissions in Large Helical Device (LHD) has been upgraded to measure two- dimensional distributions of impurity line emissions with an extension of working wavelength range to 30-650% The two-dimensional measurement is performed by scanning the observation chord horizontally. A rectangular plasma region of 520 × 700 mm2 in vertical and horizontal sizes can be observed during a single horizontal scan. The horizontal scan requires a time duration of 5 s at least. The spatial resolution is 10 mm in the vertical direction when a spatial-resolution slit of 0.2 mm in width is adopted. Although a spatial resolution in the toroidal direction is 75 mm, it is a function of CCD exposure time and horizontal scanning speed. Two-dimensional distribution of EUV line emissions from several impurities has been successfully observed for the first time from steady discharges in LHD. In this paper two-dimensional distributions of He II (303.78A), C V (40.27A), C VI (33.73A) and Fe XX (132.85A) located at different radial positions are presented with simple analysis on the magnetic field structure of LHD. 展开更多
关键词 EUV spectrometer impurity line emission two-dimensional distribution
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Distribution of c-erbB2 Antisense Probe Labeled with Superparamagnetic Iron Oxide Nanoparticles in the Major Organs of Mice on MR Imaging
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作者 Zhipeng Wen Haiyan Liu +3 位作者 Hairong He Shude Tan Ming Wen Shaolin Li 《Advances in Nanoparticles》 2013年第1期16-20,共5页
Background: The aim of this study was to investigate the distribution of the c-erbB2 antisense probe labeled with superparamagnetic iron oxide nanoparticles in the major organs of mice by MR imaging. Methods: Sixty BA... Background: The aim of this study was to investigate the distribution of the c-erbB2 antisense probe labeled with superparamagnetic iron oxide nanoparticles in the major organs of mice by MR imaging. Methods: Sixty BALB/c mice were randomly divided into experimental and control groups. MR scans were performed in each mouse of the experimental group at five different time points (10, 30, 60, 180 and 360 min) after injection of the antisense probe. The signal from each major organ (liver, spleen, heart, kidney and muscle tissue) in comparison with the background signal (signal to noise ratio) was determined at each time point as a measure of the distribution of the antisense probe. Six control mice were killed at each of the same time points and the organs immediately removed for determination of their iron content. Results: After injection of the antisense probe, the highest enrichment of the probe was seen in the spleen, reaching a peak at 180 min, followed by the liver, muscle, heart and kidney. Conclusions: MR imaging can visualize the distribution of c-erbB2 antisense probe labeled with superparamagnetic iron oxide nanoparticles in the major organs of mice, and this may provide the basis for further in vivo studies of MR imaging time and dose selection. 展开更多
关键词 ANTISENSE OLIGODEOXYNUCLEOTIDE SUPERPARAMAGNETIC IRON Oxide Mr imaging IRON Concentration Vivo distribution
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A Two-Dimensional Brightness Distribution of the Visible Zodiacal Light
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作者 S.M.Kwon 1, S.S.Hong 2, J.L.Weinberg 3 1 ( Dept. of Science Education, Kangwon Nat. Univ., Chunchon 200 701,KOREA ) 2 ( Department of Astronomy, Seoul Nat. Univ., Seoul 151 742,KOREA ) 3 ( Technology Care Givers, Snellville,G A 30039,U.S.A. ) 《天文研究与技术》 CSCD 1999年第S1期269-273,共5页
By adopting a recently developed semi empirical methodology for removing the atmospheric diffuse light and an improved technique of individual star subtraction, we have newly reduced the distribution of the visible zo... By adopting a recently developed semi empirical methodology for removing the atmospheric diffuse light and an improved technique of individual star subtraction, we have newly reduced the distribution of the visible zodiacal light (ZL) brightness from almucantar scan observations of the night sky brightness at Mt. Haleakala, Hawaii. The resulting two dimensional map of the ZL brightness covers the sky over 40°≤λ-λ ⊙≤320° and -40°≤β≤40° and its angular resolution 2°×2°is fine enough to reveal optical counterparts of the structures in the zodiacal emission first found from the IRAS space observations. 展开更多
关键词 Visible Zodiacal Light PH A two-dimensional Brightness distribution of the
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Experimental Study of Vertical Two-dimensional Diffusion Concentration Distribution in Sloped Wave Bank Angular Field
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作者 Zhengtao YANG Xiuying YU +5 位作者 Li YAO Hongtao SHAN Changai ZHANG Bing GUO Zhouhu WU Shurong XIN 《Agricultural Biotechnology》 CAS 2020年第1期101-109,共9页
[Objectives] This study was conducted to detect the two-dimensional diffusion concentration distribution from sloped wave bank. [Methods] Diffusion experiments of instantaneous line source discharge were carried out u... [Objectives] This study was conducted to detect the two-dimensional diffusion concentration distribution from sloped wave bank. [Methods] Diffusion experiments of instantaneous line source discharge were carried out using two sloped wave banks with different inclination angles based on the developed two-dimensional diffusion tank device for sloped wave banks by the apex discharge method under grid oscillation frequencies n=15, 20, 40 and 60 r/min. The image acquisition and digital image processing techniques were applied to measure the two-dimensional concentration field distribution and to analyze the distribution laws of the pollutant in the angular field. [Results] The diffusion of the pollutant in the sloped wave bank area became faster with the increase of the grid oscillation frequency, and the pollution range became wider with the diffusion time. The point concentration of the pollutant at the water surface monotonically decreased with the increase of the abscissa, and the vertical concentration distribution decreased with the increase of water depth. The transverse diffusion rate of the pollutant in water was greater than the vertical diffusion rate, and its concentration distribution exhibited a distribution characteristic of farther diffusion in the adjacent area on the water surface. The diffusion experiment area of the sloped wave bank at θ=30° had a higher concentration of the pollutant at each point compared with the diffusion experiment of the sloped bank at θ=45°, under the same experimental conditions. A large-scale vortex appeared near the sloped wave bank at θ=45° during the experiment, and the presence of the vortex made the concentration distribution of the pollutant in the direction along the bank slope first decrease and then increase, while no obvious vortex was observed near the sloped wave bank at θ=30°, and the concentration of the pollutant decreased monotonously along the bank slope direction. [Conclusions] This study is of great significance for the concentration distribution laws and the lateral and vertical diffusion coefficients of side discharge at complex bank slopes and river banks. 展开更多
关键词 Sloped wave bank Digital image processing Concentration distribution Experimental research
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Value of two-dimensional speckle tracking imaging in quantitative assessment of left ventricular function in patients with OSAS
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作者 Guo-Ping Xie Qing-Shan Lin Chao Yu 《Journal of Hainan Medical University》 2019年第10期75-78,共4页
Objective: To research the clinical application of two-dimensional speckle tracking imaging (2D-STI) in quantitative assessment of left ventricular function in patients with obstructive sleep apnea-hypopnea syndrome (... Objective: To research the clinical application of two-dimensional speckle tracking imaging (2D-STI) in quantitative assessment of left ventricular function in patients with obstructive sleep apnea-hypopnea syndrome (OSAS). Method: From July 2016 to December 2018, 86 patients with OSAS were selected as OSAS group. According to sleep apnea hypopnea index (AHI), they were divided into mild OSAS group (24 cases), moderate OSAS group (29 cases) and severe OSAS group (33 cases). Another 50 healthy volunteers who underwent physical examination in our hospital during the same period were selected as the control group. The left ventricular function of all patients was quantitatively assessed by 2D-STI. The left ventricular function of all patients was quantitatively assessed by 2D-STI. The results of routine echocardiography and left ventricular global strain parameters of the OSAS group, the control group and the OSAS patients with different severity were compared and analyzed. Result: There were no significant differences in the levels of left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDd), left ventricular end systolic diameter (LVESd) between the two groups and OSAS patients with different severity (P>0.05). The levels of IVST, LVPW and LVMI in the OSAS group were significantly higher than those in the control group, the levels of end-diastolic interventricular septal thickness (IVS), left ventricular posterior wall thickness (LVPW), left ventricular mass index (LVMI) in the severe OSAS group were significantly higher than those in the mild and moderate OSAS group, and the levels of IVST, LVPW and LVMI in the moderate OSAS group were significantly higher than those in the mild OSAS group, there were significant differences between groups (P<0.05). The levels of GLS, GRS and GCS in the OSAS group were significantly lower than those in the control group (P<0.05). GLS, GRS and GCS levels in the severe OSAS group were significantly lower than those in the mild OSAS group and the moderate OSAS group, while the levels of global longitudinal strain (GLS), global radial strain (GRS) and global circumferential strain (GCS) in the moderate OSAS group were significantly lower than those in the mild OSAS group (P<0.05). Conclusion: The left ventricular systolic function of OSAS patients is obviously impaired. Left ventricular function in OSAS patients can be assessed timely and accurately by two-dimensional speckle tracking imaging. 展开更多
关键词 OBSTRUCTIVE sleep APNEA HYPOPNEA syndrome ECHOCARDIOGRAPHY LEFT VENTRICULAR global strain parameters two-dimensional speckle tracking imaging LEFT VENTRICULAR function
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Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease 被引量:2
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作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming Zhang Jiahui Cheng Qi Zhang Wei Zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome SIRT1-PGC1α regional brain distribution whole brain clearing and imaging
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New two-dimensional fuzzy C-means clustering algorithm for image segmentation 被引量:4
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作者 周鲜成 申群太 刘利枚 《Journal of Central South University of Technology》 EI 2008年第6期882-887,共6页
To solve the problem of poor anti-noise performance of the traditional fuzzy C-means (FCM) algorithm in image segmentation, a novel two-dimensional FCM clustering algorithm for image segmentation was proposed. In this... To solve the problem of poor anti-noise performance of the traditional fuzzy C-means (FCM) algorithm in image segmentation, a novel two-dimensional FCM clustering algorithm for image segmentation was proposed. In this method, the image segmentation was converted into an optimization problem. The fitness function containing neighbor information was set up based on the gray information and the neighbor relations between the pixels described by the improved two-dimensional histogram. By making use of the global searching ability of the predator-prey particle swarm optimization, the optimal cluster center could be obtained by iterative optimization, and the image segmentation could be accomplished. The simulation results show that the segmentation accuracy ratio of the proposed method is above 99%. The proposed algorithm has strong anti-noise capability, high clustering accuracy and good segment effect, indicating that it is an effective algorithm for image segmentation. 展开更多
关键词 image segmentation fuzzy C-means clustering particle swarm optimization two-dimensional histogram
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The Uptake and Distribution Evidence of Nano-and Microplastics in vivo after a Single High Dose of Oral Exposure
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作者 HONG Tao SUN Wei +9 位作者 DENG Yuan LYU Jian Da JIN Cui Hong BAI Ying Long NA Jun ZHANG Rui GAO Yuan PAN Guo Wei YANG Zuo Sen YAN Ling Jun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第1期31-41,共11页
Objective Tissue uptake and distribution of nano-/microplastics was studied at a single high dose by gavage in vivo.Methods Fluorescent microspheres(100 nm,3μm,and 10μm)were given once at a dose of 200 mg/(kg∙body w... Objective Tissue uptake and distribution of nano-/microplastics was studied at a single high dose by gavage in vivo.Methods Fluorescent microspheres(100 nm,3μm,and 10μm)were given once at a dose of 200 mg/(kg∙body weight).The fluorescence intensity(FI)in observed organs was measured using the IVIS Spectrum at 0.5,1,2,and 4 h after administration.Histopathology was performed to corroborate these findings.Results In the 100 nm group,the FI of the stomach and small intestine were highest at 0.5 h,and the FI of the large intestine,excrement,lung,kidney,liver,and skeletal muscles were highest at 4 h compared with the control group(P<0.05).In the 3μm group,the FI only increased in the lung at 2 h(P<0.05).In the 10μm group,the FI increased in the large intestine and excrement at 2 h,and in the kidney at 4 h(P<0.05).The presence of nano-/microplastics in tissues was further verified by histopathology.The peak time of nanoplastic absorption in blood was confirmed.Conclusion Nanoplastics translocated rapidly to observed organs/tissues through blood circulation;however,only small amounts of MPs could penetrate the organs. 展开更多
关键词 Microplastics Nanoplastics IVIS Spectrum small-animal imaging system Tissue distribution BLOOD
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A"messenger zone hypothesis"based on the visual three-dimensional spatial distribution of motoneurons innervating deep limb muscles
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作者 Chen Huang Shen Wang +3 位作者 Jin Deng Xinyi Gu Shuhang Guo Xiaofeng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1559-1567,共9页
Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneuro... Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneurons innervating differe nt muscles is limited.In this study,we investigated the spatial distribution and relative position of different motoneurons that control the deep muscles of the mouse hindlimbs,which were innervated by the obturator nerve,femoral nerve,inferior gluteal nerve,deep pe roneal nerve,and tibial nerve.Locations were visualized by combining a multiplex retrograde tracking technique compatible with three-dimensional imaging of solvent-cleared o rgans(3DISCO)and 3-D imaging technology based on lightsheet fluorescence microscopy(LSFM).Additionally,we propose the hypothesis that"messenger zones"exist as interlaced areas between the motoneuron pools that dominate the synergistic or antagonist muscle groups.We hypothesize that these interlaced neurons may participate in muscle coordination as messenger neurons.Analysis revealed the precise mutual positional relationships among the many motoneurons that innervate different deep muscles of the mouse.Not only do these findings update and supplement our knowledge regarding the overall spatial layout of spinal motoneurons that control mouse limb muscles,but they also provide insights into the mechanisms through which muscle activity is coordinated and the architecture of motor circuits. 展开更多
关键词 3-D imaging MOTONEURONS multiple retrograde tracing muscle coordination skeletal muscle spatial distribution optical tissue clearing
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Quantum Image Searching Based on Probability Distributions 被引量:3
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作者 Fei Yan Abdullah M. Iliyasu +4 位作者 Chastine Fatichah Martin L. Tangel Janet P. Betancourt Fangyan Dong Kaoru Hirota 《Journal of Quantum Information Science》 2012年第3期55-60,共6页
A quantum image searching method is proposed based on the probability distributions of the readouts from the quantum measurements. It is achieved by using low computational resources which are only a single Hadamard g... A quantum image searching method is proposed based on the probability distributions of the readouts from the quantum measurements. It is achieved by using low computational resources which are only a single Hadamard gate combined with m + 1 quantum measurement operations. To validate the proposed method, a simulation experiment is used where the image with the highest similarity value of 0.93 to the particular test image is retrieved as the search result from 4 × 4 binary image database. The proposal provides a basic step for designing a search engine on quantum computing devices where the image in the database is retrieved based on its similarity to the test image. 展开更多
关键词 QUANTUM COMPUTATION imagE Processing QUANTUM imagE QUANTUM CIRCUIT imagE SEARCHING PROBABILITY distribution
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Two-dimensional cross entropy multi-threshold image segmentation based on improved BBO algorithm 被引量:2
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作者 LI Wei HU Xiao-hui WANG Hong-chuang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第1期42-49,共8页
In order to improve the global search ability of biogeography-based optimization(BBO)algorithm in multi-threshold image segmentation,a multi-threshold image segmentation based on improved BBO algorithm is proposed.Whe... In order to improve the global search ability of biogeography-based optimization(BBO)algorithm in multi-threshold image segmentation,a multi-threshold image segmentation based on improved BBO algorithm is proposed.When using BBO algorithm to optimize threshold,firstly,the elitist selection operator is used to retain the optimal set of solutions.Secondly,a migration strategy based on fusion of good solution and pending solution is introduced to reduce premature convergence and invalid migration of traditional migration operations.Thirdly,to reduce the blindness of traditional mutation operations,a mutation operation through binary computation is created.Then,it is applied to the multi-threshold image segmentation of two-dimensional cross entropy.Finally,this method is used to segment the typical image and compared with two-dimensional multi-threshold segmentation based on particle swarm optimization algorithm and the two-dimensional multi-threshold image segmentation based on standard BBO algorithm.The experimental results show that the method has good convergence stability,it can effectively shorten the time of iteration,and the optimization performance is better than the standard BBO algorithm. 展开更多
关键词 two-dimensional cross entropy biogeography-based optimization(BBO)algorithm multi-threshold image segmentation
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