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Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion
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作者 Li An Jianyi Li +8 位作者 Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian Xi * Zhichuan JXu Chun‑Hua Yan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期340-354,共15页
Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has ... Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity enhancement.Here,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is reported.The substituting Fe content influences both current change tendency and surface reconstruction degree.LaNi_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)series.The reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based catalysts.Besides,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability.Furthermore,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree.The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction.This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation. 展开更多
关键词 Oxygen evolution reaction Perovskite oxides DOPING Activation and reconstruction
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Navigating medial patellotibial ligament reconstruction:Clinical perspectives and surgical strategies
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作者 Juan Pablo Zicaro Ignacio Garcia-Mansilla 《World Journal of Clinical Cases》 SCIE 2025年第1期6-10,共5页
The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when required.The medial ... The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when required.The medial patellotibial ligament and the medial patellomeniscal ligament are secondary stabilizers of the patella.Despite this,both the medial patellotibial and patellofemoral ligaments aid in patellar rotation and tilt when the knee is flexed beyond 45°.The medial patellotibial ligament plays a particularly important role in the final stages of stretching in extension and between 40 degrees to 90 degrees of flexion.The clinical relevance and surgical indications for medial patellotibial ligament reconstruction associated with medial patellofemoral ligament reconstruction are still controversial.This editorial explores the surgical indications and clinical results for medial patellotibial ligament reconstruction to improve readers’understanding of this technique,especially because reported clinical outcomes have remained sparse. 展开更多
关键词 Medial patellotibial ligament Patellar instability reconstruction SURGICAL
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THE SPECTRAL RADIUS OF UNIFORM HYPERGRAPH DETERMINED BY THE SIGNLESS LAPLACIAN MATRIX
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作者 HE Fang-guo 《数学杂志》 2025年第1期1-12,共12页
This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh ... This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh principle and the perturbation of the spectral radius under moving the edge operation,and the extremal hypergraphs are characterized for both supertree and unicyclic hypergraphs.The spectral radius of the graph is generalized. 展开更多
关键词 spectral radius uniform hypergraph Signless Laplasian matrix
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Exploration of Gas‑Dependent Self‑Adaptive Reconstruction Behavior of Cu_(2)O for Electrochemical CO_(2)Conversion to Multi‑Carbon Products
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作者 Chaoran Zhang Yichuan Gu +7 位作者 Qu Jiang Ziyang Sheng Ruohan Feng Sihong Wang Haoyue Zhang Qianqing Xu Zijian Yuan Fang Song 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期280-296,共17页
Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)acc... Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic performances.The CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution reaction.With the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO intermediates.Additionally,we find extra CO production is indispensable for the robust production of C2H4.An inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable electrolysis.Guided by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing C2H4.Our work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes. 展开更多
关键词 CO_(2)reduction reaction ELECTROCATALYSTS Cu_(2)O reconstruction Self-adaptive electrocatalysis
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Passive-source multitaper-spectral method based low-frequency data reconstruction for active seismic sources 被引量:3
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作者 张盼 韩立国 +2 位作者 周岩 许卓 葛奇鑫 《Applied Geophysics》 SCIE CSCD 2015年第4期585-597,629,630,共15页
Passive seismic data contain large amounts of low-frequency information. To effectively extract and compensate active seismic data that lack low frequencies, we propose a multitaper spectral reconstruction method base... Passive seismic data contain large amounts of low-frequency information. To effectively extract and compensate active seismic data that lack low frequencies, we propose a multitaper spectral reconstruction method based on multiple sinusoidal tapers and derive equations for multisource and multitrace conditions. Compared to conventional cross correlation and deconvolution reconstruction methods, the proposed method can more accurately reconstruct the relative amplitude of recordings. Multidomain iterative denoising improves the SNR of retrieved data. By analyzing the spectral characteristics of passive data before and after reconstruction, we found that the data are expressed more clearly after reconstruction and denoising. To compensate for the low-frequency information in active data using passive seismic data, we match the power spectrum, supplement it, and then smooth it in the frequency domain. Finally, we use numerical simulation to verify the proposed method and conduct prestack depth migration using data after low-frequency compensation. The proposed power-matching method adds the losing low frequency information in the active seismic data using the low-frequency information of passive- source seismic data. The imaging of compensated data gives a more detailed information of deep structures. 展开更多
关键词 Passive source multitaper spectral reconstruction low-frequency compensation power matching
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Investigation of prior image constrained compressed sensing-based spectral X-ray CT image reconstruction
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作者 周正东 余子丽 +1 位作者 张雯雯 管绍林 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期420-425,共6页
To improve spectral X-ray CT reconstructed image quality, the energy-weighted reconstructed image xbins^W and the separable paraboloidal surrogates(SPS) algorithm are proposed for the prior image constrained compres... To improve spectral X-ray CT reconstructed image quality, the energy-weighted reconstructed image xbins^W and the separable paraboloidal surrogates(SPS) algorithm are proposed for the prior image constrained compressed sensing(PICCS)-based spectral X-ray CT image reconstruction. The PICCS-based image reconstruction takes advantage of the compressed sensing theory, a prior image and an optimization algorithm to improve the image quality of CT reconstructions.To evaluate the performance of the proposed method, three optimization algorithms and three prior images are employed and compared in terms of reconstruction accuracy and noise characteristics of the reconstructed images in each energy bin.The experimental simulation results show that the image xbins^W is the best as the prior image in general with respect to the three optimization algorithms; and the SPS algorithm offers the best performance for the simulated phantom with respect to the three prior images. Compared with filtered back-projection(FBP), the PICCS via the SPS algorithm and xbins^W as the prior image can offer the noise reduction in the reconstructed images up to 80. 46%, 82. 51%, 88. 08% in each energy bin,respectively. M eanwhile, the root-mean-squared error in each energy bin is decreased by 15. 02%, 18. 15%, 34. 11% and the correlation coefficient is increased by 9. 98%, 11. 38%,15. 94%, respectively. 展开更多
关键词 spectral X-ray CT prior image compressed sensing optimization algorithm image reconstruction
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An efficient source wavefield reconstruction scheme using single boundary layer values for the spectral element method 被引量:3
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作者 YouShan Liu Tao Xu +3 位作者 YangHua Wang JiWen Teng José Badal HaiQiang Lan 《Earth and Planetary Physics》 CSCD 2019年第4期342-357,共16页
In the adjoint-state method, the forward-propagated source wavefield and the backward-propagated receiver wavefield must be available simultaneously either for seismic imaging in migration or for gradient calculation ... In the adjoint-state method, the forward-propagated source wavefield and the backward-propagated receiver wavefield must be available simultaneously either for seismic imaging in migration or for gradient calculation in inversion. A feasible way to avoid the excessive storage demand is to reconstruct the source wavefield backward in time by storing the entire history of the wavefield in perfectly matched layers. In this paper, we make full use of the elementwise global property of the Laplace operator of the spectral element method (SEM) and propose an efficient source wavefield reconstruction method at the cost of storing the wavefield history only at single boundary layer nodes. Numerical experiments indicate that the accuracy of the proposed method is identical to that of the conventional method and is independent of the order of the Lagrange polynomials, the element type, and the temporal discretization method. In contrast, the memory-saving ratios of the conventional method versus our method is at least N when using either quadrilateral or hexahedron elements, respectively, where N is the order of the Lagrange polynomials used in the SEM. A higher memorysaving ratio is achieved with triangular elements versus quadrilaterals. The new method is applied to reverse time migration by considering the Marmousi model as a benchmark. Numerical results demonstrate that the method is able to provide the same result as the conventional method but with about 1/25 times lower storage demand. With the proposed wavefield reconstruction method, the storage demand is dramatically reduced;therefore, in-core memory storage is feasible even for large-scale three-dimensional adjoint inversion problems. 展开更多
关键词 spectral element METHOD SOURCE wavefield reconstruction SINGLE boundary layer memory-saving ratio ADJOINT METHOD reverse time migration
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DOA estimation of wideband signals based on iterative spectral reconstruction 被引量:4
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作者 Shun He Zhiwei Yang Guisheng Liao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1039-1045,共7页
In order to solve the problem of coherent signal subspace method(CSSM) depending on the estimated accuracy of signal subspace, a new direction of arrival(DOA) estimation method of wideband source, which is based on it... In order to solve the problem of coherent signal subspace method(CSSM) depending on the estimated accuracy of signal subspace, a new direction of arrival(DOA) estimation method of wideband source, which is based on iterative adaptive spectral reconstruction, is proposed. Firstly, the wideband signals are divided into several narrowband signals of different frequency bins by discrete Fourier transformation(DFT). Then, the signal matched power spectrum in referenced frequency bins is computed, which can form the initial covariance matrix. Finally, the linear restrained minimum variance spectral(Capon spectral) of signals in other frequency bins are reconstructed using sequential iterative means, so the DOA can be estimated by the locations of spectral peaks. Theoretical analysis and simulation results show the proposed method based on the iterative spectral reconstruction for the covariance matrices of all sub-bands can avoid the problem of determining the signal subspace accurately with the coherent signal subspace method under the conditions of small samples and low signal to noise ratio(SNR), and it can also realize full dimensional focusing of different sub-band data, which can be applied to coherent sources and can significantly improve the accuracy of DOA estimation. 展开更多
关键词 direction of arrival(DOA) wideband source coherent source minimum variance spectral
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SPECTRAL/HP ELEMENT METHOD WITH HIERARCHICAL RECONSTRUCTION FOR SOLVING NONLINEAR HYPERBOLIC CONSERVATION LAWS
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作者 Zhiliang Xu Guang Lin 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1737-1748,共12页
The hierarchical reconstruction (HR) [Liu, Shu, Tadmor and Zhang, SINUM '07] has been successfully applied to prevent oscillations in solutions computed by finite volume, Runge-Kutta discontinuous Galerkin, spectra... The hierarchical reconstruction (HR) [Liu, Shu, Tadmor and Zhang, SINUM '07] has been successfully applied to prevent oscillations in solutions computed by finite volume, Runge-Kutta discontinuous Galerkin, spectral volume schemes for solving hyperbolic conservation laws. In this paper, we demonstrate that HR can also be combined with spectral/hp element method for solving hyperbolic conservation laws. An orthogonal spectral basis written in terms of Jacobi polynomials is applied. High computational efficiency is obtained due to such matrix-free algorithm. The formulation is conservative, and essential nomoscillation is enforced by the HR limiter. We show that HR preserves the order of accuracy of the spectral/hp element method for smooth solution problems and generate essentially non-oscillatory solutions profiles for capturing discontinuous solutions without local characteristic decomposition. In addition, we introduce a postprocessing technique to improve HR for limiting high degree numerical solutions. 展开更多
关键词 spectral/hp element method hierarchical reconstruction discontinuous Galerkin hyperbolic conservation laws
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Diagnostic Value of Spectral CT Reconstruction Mode for Carotid Atherosclerotic Plaque Lesions
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作者 Junying Bi Yanni Zeng +2 位作者 Jun Meng Tiantian Zhou Xiang Gao 《Journal of Clinical and Nursing Research》 2020年第4期36-39,共4页
Objective:To investigate the diagnostic value of spectral CT reconstruction mode for carotid atherosclerotic plaque lesions.Methods:From January 2017 to January 2019,70 patients with carotid atherosclerotic plaque les... Objective:To investigate the diagnostic value of spectral CT reconstruction mode for carotid atherosclerotic plaque lesions.Methods:From January 2017 to January 2019,70 patients with carotid atherosclerotic plaque lesions in our hospita1 were selected as the research object.A11 patients were diagnosed with cervical vascular color Doppler ultrasound and spectral CT scan under spectral cr reconstruction mode.Taking the results of coronaryf angiography as the"gold standard",the clinical value of the two examination methods in the diagnosis of carotid atherosclerotic plaque lesions was compared and analyzed.Results:Coronary angiography diagnosis confirmed that 33 of 70 patients with suspected carotid atherosclerotic plaque lesions had vulnerable plaques and 37 had stable plaques.The accuracy of Spectral CT examination of carotid artery plaque was 87.14%(61/70),sensitivity was 90.91%(30/33),specificity was 83.78%(31/37),and the positive predictive value was 83.33%(30/36),the negative predictive value is 91.76%(31/34),which is higher than that of cervical vascular ultrasonography(61.43%,60.61%,56.76%,57.89%,65.63%),the difference is statistically significant(P<0.05).Conclusion:The application of Spectral CT in the clinical diagnosis and treatment of carotid atherosclerotic plaque lesions with higher accuracy,sensitivity and specificity,is more significant and can provide a more reliable and effective imaging basis. 展开更多
关键词 Carotid atherosc1erosis Plaque 1esions spectral CT reconstruction mode
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Application of multi-planar reconstruction technique in endovascular repair of aortic dissection 被引量:1
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作者 Guo-Jie Li Ming-Xian Zhao 《World Journal of Clinical Cases》 SCIE 2024年第17期2989-2994,共6页
BACKGROUND Endovascular repair of aortic dissection is an effective method commonly used in the treatment of Stanford type B aortic dissection.Stent placement during the operation was one-time and could not be repeate... BACKGROUND Endovascular repair of aortic dissection is an effective method commonly used in the treatment of Stanford type B aortic dissection.Stent placement during the operation was one-time and could not be repeatedly adjusted during the operation.Therefore,it is of great significance for cardiovascular physicians to fully understand the branch status,position,angle,and other information regarding aortic arch dissection before surgery.AIM To provide more references for clinical cardiovascular physicians to develop treatment plans.METHODS Data from 153 patients who underwent endovascular repair of aortic dissection at our hospital between January 2021 and December 2022 were retrospectively collected.All patients underwent multi-slice spiral computed tomography angiography.Based on distinct post-image processing techniques,the patients were categorized into three groups:Multiplanar reconstruction(MPR)(n=55),volume reconstruction(VR)(n=46),and maximum intensity projection(MIP)(n=52).The detection rate of aortic rupture,accuracy of the DeBakey classification,rotation,and tilt angles of the C-arm during the procedure,dispersion after stent release,and the incidence of late complications were recorded and compared.RESULTS The detection rates of interlayer rupture in the MPR and VR groups were significantly higher than that in the MIP group(P<0.05).The detection rates of De-Bakey subtypesⅠ,Ⅱ,andⅢin the MPR group were higher than those in the MIP group,and the detection rate of typeⅢin the MPR group was significantly higher than that in the VR group(P<0.05).There was no statistically significant difference in the detection rates of typesⅠandⅡcompared to the VR group(P>0.05).The scatter rate of markers and the incidence of complications in the MPR group were significantly lower than those in the VR and MIP groups(P<0.05).CONCLUSION The application of MPR in the endovascular repair of aortic dissection has improved the detection rate of dissection rupture,the accuracy of anatomical classification,and safety. 展开更多
关键词 Multiplanar reconstruction Endovascular repair of aortic dissection Image-processing technology Rate of aortic rupture Volume reconstruction
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FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT 被引量:1
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作者 Wei Jiang Ping Cao +5 位作者 Yi-Ming Wu Xian-Ke Liu Zhu-Jun Fang Zhi-Yong Zhang Bin Shi Jun Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期96-108,共13页
A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas detector.To address the issue of long process... A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas detector.To address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber principle.This method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined RAM.The performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data transmission.The experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 mm.The beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction method.The online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT. 展开更多
关键词 Position reconstruction FPGA Readout electronics Neutron flux spatial distribution
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Predictive factors for coronal and sagittal graft extrusion length after using tendon autograft for medial meniscus reconstruction 被引量:1
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作者 Tian-Wang Zhu Xian-Xiang Xiang +2 位作者 Chun-Hui Li Rui-Xin Li Nan Zhang 《World Journal of Orthopedics》 2024年第11期1036-1046,共11页
BACKGROUND Meniscus extrusion occurs in most elderly individuals and most patients after meniscus allograft transplantation.The risk factors and correlative factors of meniscus extrusion have been extensively studied.... BACKGROUND Meniscus extrusion occurs in most elderly individuals and most patients after meniscus allograft transplantation.The risk factors and correlative factors of meniscus extrusion have been extensively studied.However,for using tendon autograft for meniscus reconstruction,both graft type and surgical method are different from those in previous studies on meniscus extrusion.AIM To identify predictive factors for coronal and sagittal graft extrusion length after using tendon autograft for medial meniscus reconstruction.METHODS Ten patients who underwent medial meniscus reconstruction with tendon autograft were selected for this retrospective observational study.The graft extrusions and potential factors were measured and correlation and regression analyses were performed to analyze their relationships.RESULTS The medial graft extrusion correlated with the preoperative bilateral hip-kneeankle angle difference,preoperative Kellgren-Lawrence grade,preoperative relative joint space width,and preoperative bilateral medial edge incline angle difference.The anterior graft correlated with the anterior tunnel edge distance at 1 week after operation.The posterior graft extrusion correlated with the preoperative bilateral hip-knee-ankle angle difference,preoperative relative joint space width,and posterior tunnel edge distance at 1 week after operation.The mean graft extrusion correlated with the preoperative bilateral hip-knee-ankle angle difference and preoperative relative joint space width.The preoperative joint space width and anterior and posterior tunnel edge distance at 1 week can be used to predict the medial,anterior,posterior,and mean graft extrusion length.CONCLUSION The preoperative joint space width and tunnel position can be used to predict the coronal and sagittal graft extrusion length after using tendon autograft for medial meniscus reconstruction. 展开更多
关键词 MENISCUS EXTRUSION reconstruction AUTOGRAFT GRAFT
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Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning 被引量:1
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作者 Hui-Ting Ge Jian-Wu Chen +5 位作者 Li-Li Wang Tian-Xiu Zou Bin Zheng Yuan-Fen Liu Yun-Jing Xue Wei-Wen Lin 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期542-555,共14页
BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are important prognostic factors for gastric cancer(GC)that indicate an increased risk of metastasis and poor outcomes.Accurate preoperative predictio... BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are important prognostic factors for gastric cancer(GC)that indicate an increased risk of metastasis and poor outcomes.Accurate preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment deci-sions.However,prior models using conventional computed tomography(CT)images to predict LVI or PNI separately have had limited accuracy.Spectral CT provides quantitative enhancement parameters that may better capture tumor invasion.We hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC patients.AIM To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status accurately.METHODS This study used a retrospective dataset involving 257 GC patients(training cohort,n=172;validation cohort,n=85).First,several clinical indicators,including serum tumor markers,CT-TN stages and CT-detected extramural vein invasion(CT-EMVI),were extracted,as were quantitative spectral CT parameters from the delineated tumor regions.Next,a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters.A logistic regression(LR)-based nomogram model was subsequently constructed to predict LVI/PNI status,and its performance was evaluated using the area under the receiver operating characteristic curve(AUC).RESULTS In both the training and validation cohorts,CT T3-4 stage,CT-N positive status,and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant(P<0.05).LR analysis of the training group showed preoperative CT-T stage,CT-EMVI,single-energy CT values of 70 keV of venous phase(VP-70 keV),and the ratio of standardized iodine concentration of equilibrium phase(EP-NIC)were independent influencing factors.The AUCs of VP-70 keV and EP-NIC were 0.888 and 0.824,respectively,which were slightly greater than those of CT-T and CT-EMVI(AUC=0.793,0.762).The nomogram combining CT-T stage,CT-EMVI,VP-70 keV and EP-NIC yielded AUCs of 0.918(0.866-0.954)and 0.874(0.784-0.936)in the training and validation cohorts,which are significantly higher than using each of single independent factors(P<0.05).CONCLUSION The study found that using portal venous and EP spectral CT parameters allows effective preoperative detection of LVI/PNI in GC,with accuracy boosted by integrating clinical markers. 展开更多
关键词 spectral computed tomography Gastric cancer Lymphovascular invasion Perineural invasion
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Reactor field reconstruction from sparse and movable sensors using Voronoi tessellation-assisted convolutional neural networks 被引量:1
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作者 He-Lin Gong Han Li +1 位作者 Dunhui Xiao Sibo Cheng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期173-185,共13页
The aging of operational reactors leads to increased mechanical vibrations in the reactor interior.The vibration of the incore sensors near their nominal locations is a new problem for neutronic field reconstruction.C... The aging of operational reactors leads to increased mechanical vibrations in the reactor interior.The vibration of the incore sensors near their nominal locations is a new problem for neutronic field reconstruction.Current field-reconstruction methods fail to handle spatially moving sensors.In this study,we propose a Voronoi tessellation technique in combination with convolutional neural networks to handle this challenge.Observations from movable in-core sensors were projected onto the same global field structure using Voronoi tessellation,holding the magnitude and location information of the sensors.General convolutional neural networks were used to learn maps from observations to the global field.The proposed method reconstructed multi-physics fields(including fast flux,thermal flux,and power rate)using observations from a single field(such as thermal flux).Numerical tests based on the IAEA benchmark demonstrated the potential of the proposed method in practical engineering applications,particularly within an amplitude of 5 cm around the nominal locations,which led to average relative errors below 5% and 10% in the L_(2) and L_(∞)norms,respectively. 展开更多
关键词 Voronoi tessellation Field reconstruction Nuclear reactors Reactor physics On-line monitoring
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Spectral reconstruction of the flash X-ray generated by Dragon-I LIA based on transmission measurements
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作者 曹靖 肖睿 +2 位作者 陈楠 曹宏睿 阴泽杰 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第4期61-64,共4页
The Dragon-I linear induction accelerator(LIA)at China Academy of Engineering Physics generates 20 Me V flash X-rays mainly for radiography applications in fluid dynamics.Its spectral information is quite important fo... The Dragon-I linear induction accelerator(LIA)at China Academy of Engineering Physics generates 20 Me V flash X-rays mainly for radiography applications in fluid dynamics.Its spectral information is quite important for diagnostic X-ray imaging applications,but because of its short pulse and great radiation intensity,direct measurement is impossible.In this work,we propose a new method based on transmission measurements to obtain the flash X-ray spectrum.Pure iron cylinders were used as attenuation material,and alanine dosimeters were attached on their rear bottom to record the dose after different degrees of attenuation.Iterative least square method was used to unfold the spectrum,while Geant4 Monte Carlo code was used to simulate the X-ray spectrum.The unfolded spectrum and the simulated spectrum have a high degree of consistency,with the reduced chi-square value of 0.044.This shows that the method is reliable in estimating megavoltage highintensity X-ray spectrum. 展开更多
关键词 闪光X射线 光谱重建 传输测量 神龙 中国工程物理研究院 直线感应加速器 迭代最小二乘法 GEANT4
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Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers 被引量:1
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作者 DU Zun-feng ZHU Hai-ming YU Jian-xing 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期285-296,共12页
When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fa... When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real risers.The problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration modes.However,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known measurements.This study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal space.In the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring. 展开更多
关键词 motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing
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Estimation-free spatial-domain image reconstruction of structured illumination microscopy 被引量:1
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作者 Xiaoyan Li Shijie Tu +4 位作者 Yile Sun Yubing Han Xiang Hao Cuifang kuang Xu Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期45-58,共14页
Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditiona... Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditional Wiener-filtering-based reconstruction algorithm operates in the Fourier domain,it requires prior knowledge of the sinusoidal illumination patterns which makes the time-consuming procedure of parameter estimation to raw datasets necessary,besides,the parameter estimation is sensitive to noise or aberration-induced pattern distortion which leads to reconstruction artifacts.Here,we propose a spatial-domain image reconstruction method that does not require parameter estimation but calculates patterns from raw datasets,and a reconstructed image can be obtained just by calculating the spatial covariance of differential calculated patterns and differential filtered datasets(the notch filtering operation is performed to the raw datasets for attenuating and compensating the optical transfer function(OTF)).Experiments on reconstructing raw datasets including nonbiological,biological,and simulated samples demonstrate that our method has SR capability,high reconstruction speed,and high robustness to aberration and noise. 展开更多
关键词 Structured illumination microscopy image reconstruction spatial domain digital micromirror device(DMD)
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In vitro performance of a biodegradable zinc alloy adjustable-loop cortical suspension fixation for anterior cruciate ligament reconstruction 被引量:1
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作者 Ting Wang Zhangzhi Shi +7 位作者 Hongyong Zhong Xiangmin Li Jinling Sun Wei Yin Xiaojing Ji Qiang Wang Anqi Zhao Luning Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期887-898,共12页
Anterior cruciate ligament(ACL)injuries of the knee are one of the most common and serious athletic injuries.The widely used cortical suspension fixation buttons for ligament reconstruction are permanent implants,part... Anterior cruciate ligament(ACL)injuries of the knee are one of the most common and serious athletic injuries.The widely used cortical suspension fixation buttons for ligament reconstruction are permanent implants,particularly those made from conventional steel or titanium alloys.In this study,a biodegradable Zn-0.45Mn-0.2Mg(ZMM42)alloy with the yield strength of 300.4 MPa and tensile strength of 329.8 MPa was prepared through hot extrusion.The use of zinc alloys in the preparation of cortical suspension fixation buttons was proposed for the first time.After 35 d of immersion in simulated body fluids,the ZMM42 alloy fixation buttons were degraded at a rate of 44μm/a,and the fixation strength was retained(379.55 N)in the traction loops.Simultaneously,the ZMM42 alloy fixation buttons exhibited an increase in MC3T3-E1 cell viability and high antibacterial activity against Escherichia coli and Staphylococcus aureus.These results reveal the potential of biodegradable zinc alloys for use as ligament reconstruction materials and for developing diverse zinc alloy cortical suspension fixation devices. 展开更多
关键词 anterior cruciate ligament reconstruction zinc alloy fixation buttons mechanical property corrosion behavior BIOCOMPATIBILITY
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Summarizing the evidence for robotic-assisted bladder neck reconstruction: Systematic review of patency and incontinence outcomes 被引量:1
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作者 Tenny R.Zhang Ashley Alford Lee C.Zhao 《Asian Journal of Urology》 CSCD 2024年第3期341-347,共7页
Objective:Bladder neck contracture and vesicourethral anastomotic stenosis are difficult to manage endoscopically,and open repair is associated with high rates of incontinence.In recent years,there have been increasin... Objective:Bladder neck contracture and vesicourethral anastomotic stenosis are difficult to manage endoscopically,and open repair is associated with high rates of incontinence.In recent years,there have been increasing reports of robotic-assisted bladder neck reconstruction in the literature.However,existing studies are small,heterogeneous case series.The objective of this study was to perform a systematic review of robotic-assisted bladder neck reconstruction to better evaluate patency and incontinence outcomes.Methods:We performed a systematic review of PubMed from first available date to May 2023 for all studies evaluating robotic-assisted reconstructive surgery of the bladder neck in adult men.Articles in non-English,author replies,editorials,pediatric-based studies,and reviews were excluded.Outcomes of interest were patency and incontinence rates,which were pooled when appropriate.Results:After identifying 158 articles on initial search,we included only ten studies that fit all aforementioned criteria for robotic-assisted bladder neck reconstruction.All were case series published from March 2018 to March 2022 ranging from six to 32 men,with the median follow-up of 5e23 months.A total of 119 patients were included in our analysis.A variety of etiologies and surgical techniques were described.Patency rates ranged from 50%to 100%,and pooled patency was 80%(95/119).De novo incontinence rates ranged from 0%to 33%,and pooled incontinence was 17%(8/47).Our findings were limited by small sample sizes,relatively short follow-ups,and heterogeneity between studies. 展开更多
关键词 Bladder neck CONTINENCE INCONTINENCE PATENCY Posterior urethra Reconstructive surgery Robotic surgery STENOSIS STRICTURE Surgical outcome
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