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基于MPI+CUDA的DSMC/PIC耦合模拟异构并行及性能优化研究
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作者 林拥真 徐传福 +4 位作者 邱昊中 汪青松 王正华 杨富翔 李洁 《计算机科学》 CSCD 北大核心 2024年第9期31-39,共9页
DSMC/PIC耦合模拟是一类重要的高性能计算应用,大规模DSMC/PIC耦合模拟计算量巨大,需要实现高效并行计算。由于粒子动态注入、迁移等操作,基于MPI并行的DSMC/PIC耦合模拟往往通信开销较大且难以实现负载均衡。针对自主研发的DSMC/PIC耦... DSMC/PIC耦合模拟是一类重要的高性能计算应用,大规模DSMC/PIC耦合模拟计算量巨大,需要实现高效并行计算。由于粒子动态注入、迁移等操作,基于MPI并行的DSMC/PIC耦合模拟往往通信开销较大且难以实现负载均衡。针对自主研发的DSMC/PIC耦合模拟软件,在原有MPI并行优化版本上设计实现了高效的MPI+CUDA异构并行算法,结合GPU体系结构和DSMC/PIC计算特点,开展了GPU访存优化、GPU线程工作负载优化、CPU-GPU数据传输优化及DSMC/PIC数据冲突优化等一系列性能优化。在北京北龙超级云HPC系统的NVIDIA V100和A100 GPU上,针对数亿粒子规模的脉冲真空弧等离子体羽流应用,开展了大规模DSMC/PIC耦合异构并行模拟,相比原有纯MPI并行,GPU异构并行大幅缩短了模拟时间,两块GPU卡较192核的CPU加速比达到550%,同时具有更好的强可扩展性。 展开更多
关键词 DSMC/PIC耦合 粒子模拟 异构并行 MPI+cuda
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基于神经网络的伽马射线定位算法及CUDA计算
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作者 彭敬 王磊 +4 位作者 卢位 杜雨昆 李浩炫 孟娜 邹科峰 《核电子学与探测技术》 CAS 北大核心 2024年第4期663-672,共10页
为实现便携式核辐射成像场景下利用神经网络进行伽马射线定位的快速GPU计算,提出了一种基于CUDA的伽马射线定位计算方法。首先描述了伽马射线探测器模型、MURA成像系统和神经网络射线定位模型,然后对FCNN射线定位模型进行并行计算分析,... 为实现便携式核辐射成像场景下利用神经网络进行伽马射线定位的快速GPU计算,提出了一种基于CUDA的伽马射线定位计算方法。首先描述了伽马射线探测器模型、MURA成像系统和神经网络射线定位模型,然后对FCNN射线定位模型进行并行计算分析,在Jetson Xavier NX平台下实现了基于CUDA的伽马射线定位计算,并验证了该计算方法的准确性和对其计算效率进行对比分析。实验结果表明,对于10000组事件数据,设计的基于CUDA的射线定位计算与CPU射线定位计算结果几乎一致,其实际计算耗时11.5 ms,约为CPU射线定位计算的加速比的364倍。 展开更多
关键词 辐射成像 射线定位 神经网络 推理计算 cuda
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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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Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients 被引量:1
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作者 Yan-Fen Xu Hui-Yun Ma +4 位作者 Gui-Ling Huang Yu-Ting Zhang Xue-Yan Wang Ming-Jie Wei Xiao-Qing Pei 《World Journal of Gastroenterology》 SCIE CAS 2024年第23期3005-3015,共11页
BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and ... BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making. 展开更多
关键词 Double contrast-enhanced ultrasonography Multi-detector computed tomography Gastric cancer T staging
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MPI+CUDA联合加速重力场反演的并行算法
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作者 赵锴坤 朱炬波 +1 位作者 谷德峰 韦春博 《大地测量与地球动力学》 CSCD 北大核心 2024年第4期423-428,共6页
针对重力场解算过程中数据量巨大的问题,联合MPI(massage passing interface)与CUDA(compute unified device architecture)提出基于最小二乘法的重力场解算过程的并行加速算法。使用MPI完成复杂过程的任务分配,实现全局层面的并行加速... 针对重力场解算过程中数据量巨大的问题,联合MPI(massage passing interface)与CUDA(compute unified device architecture)提出基于最小二乘法的重力场解算过程的并行加速算法。使用MPI完成复杂过程的任务分配,实现全局层面的并行加速;基于CUDA编写大规模矩阵相乘的并行加速程序,并针对不同类型的矩阵进行适配,同时联合MPI将法矩阵的计算过程进一步细分,实现对分进程内存峰值的压缩。在单机上完成30阶与120阶重力场仿真解算任务,结果表明,反演30阶重力场时加速比可达180;反演120阶重力场时,并行计算单次迭代仅耗时2 h,而串行模式下无法计算。 展开更多
关键词 重力场 并行计算 cuda MPI
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Lymphatic plastic bronchitis and primary chylothorax: A study based on computed tomography lymphangiography 被引量:1
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作者 Xing-Peng Li Yan Zhang +4 位作者 Xiao-Li Sun Kun Hao Meng-Ke Liu Qi Hao Ren-Gui Wang 《World Journal of Clinical Cases》 SCIE 2024年第14期2350-2358,共9页
BACKGROUND This study presents an evaluation of the computed tomography lymphangio-graphy(CTL)features of lymphatic plastic bronchitis(PB)and primary chylotho-rax to improve the diagnostic accuracy for these two disea... BACKGROUND This study presents an evaluation of the computed tomography lymphangio-graphy(CTL)features of lymphatic plastic bronchitis(PB)and primary chylotho-rax to improve the diagnostic accuracy for these two diseases.AIM To improve the diagnosis of lymphatic PB or primary chylothorax,a retrospective analysis of the clinical features and CTL characteristics of 71 patients diagnosed with lymphatic PB or primary chylothorax was performed.METHODS The clinical and CTL data of 71 patients(20 with lymphatic PB,41 with primary chylothorax,and 10 with lymphatic PB with primary chylothorax)were collected retrospectively.CTL was performed in all patients.The clinical manifestations,CTL findings,and conventional chest CT findings of the three groups of patients were compared.The chi-square test or Fisher's exact test was used to compare the differences among the three groups.A difference was considered to be statistically significant when P<0.05.RESULTS(1)The percentages of abnormal contrast medium deposits on CTL in the three groups were as follows:Thoracic duct outlet in 14(70.0%),33(80.5%)and 8(80.0%)patients;peritracheal region in 18(90.0%),15(36.6%)and 8(80.0%)patients;pleura in 6(30.0%),33(80.5%)and 9(90.0%)patients;pericardium in 6(30.0%),6(14.6%)and 4(40.0%)patients;and hilum in 16(80.0%),11(26.8%)and 7(70.0%)patients;and(2)the abnormalities on conven-tional chest CT in the three groups were as follows:Ground-glass opacity in 19(95.0%),18(43.9%)and 8(80.0%)patients;atelectasis in 4(20.0%),26(63.4%)and 7(70.0%)patients;interlobular septal thickening in 12(60.0%),11(26.8%)and 3(30.0%)patients;bronchovascular bundle thickening in 14(70.0%),6(14.6%)and 4(40.0%)patients;localized mediastinal changes in 14(70.0%),14(34.1%),and 7(70.0%)patients;diffuse mediastinal changes in 6(30.0%),5(12.2%),and 3(30.0%)patients;cystic lesions in the axilla in 2(10.0%),6(14.6%),and 2(20.0%)patients;and cystic lesions in the chest wall in 0(0%),2(4.9%),and 2(4.9%)patients.CONCLUSION CTL is well suited to clarify the characteristics of lymphatic PB and primary chylothorax.This method is an excellent tool for diagnosing these two diseases. 展开更多
关键词 LYMPHATIC Plastic bronchitis Primary chylothorax Direct lymphangiography computed tomography lymphangiography
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Computed tomography-based nomogram of Siewert type Ⅱ/Ⅲ adenocarcinoma of esophagogastric junction to predict response to docetaxel, oxaliplatin and S-1 被引量:1
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作者 Chuan-Qinyuan Zhou Dan Gao +7 位作者 Yan Gui Ning-Pu Li Wen-Wen Guo Hai-Ying Zhou Rui Li Jing Chen Xiao-Ming Zhang Tian-Wu Chen 《World Journal of Radiology》 2024年第1期9-19,共11页
BACKGROUND Neoadjuvant chemotherapy(NAC)has become the standard care for advanced adenocarcinoma of esophagogastric junction(AEG),although a part of the patients cannot benefit from NAC.There are no models based on ba... BACKGROUND Neoadjuvant chemotherapy(NAC)has become the standard care for advanced adenocarcinoma of esophagogastric junction(AEG),although a part of the patients cannot benefit from NAC.There are no models based on baseline computed tomography(CT)to predict response of Siewert type II or III AEG to NAC with docetaxel,oxaliplatin and S-1(DOS).AIM To develop a CT-based nomogram to predict response of Siewert type II/III AEG to NAC with DOS.METHODS One hundred and twenty-eight consecutive patients with confirmed Siewert type II/III AEG underwent CT before and after three cycles of NAC with DOS,and were randomly and consecutively assigned to the training cohort(TC)(n=94)and the validation cohort(VC)(n=34).Therapeutic effect was assessed by disease-control rate and progressive disease according to the Response Evaluation Criteria in Solid Tumors(version 1.1)criteria.Possible prognostic factors associated with responses after DOS treatment including Siewert classification,gross tumor volume(GTV),and cT and cN stages were evaluated using pretherapeutic CT data in addition to sex and age.Univariate and multivariate analyses of CT and clinical features in the TC were performed to determine independent factors associated with response to DOS.A nomogram was established based on independent factors to predict the response.The predictive performance of the nomogram was evaluated by Concordance index(C-index),calibration and receiver operating characteristics curve in the TC and VC.RESULTS Univariate analysis showed that Siewert type(52/55 vs 29/39,P=0.005),pretherapeutic cT stage(57/62 vs 24/32,P=0.028),GTV(47.3±27.4 vs 73.2±54.3,P=0.040)were significantly associated with response to DOS in the TC.Multivariate analysis of the TC also showed that the pretherapeutic cT stage,GTV and Siewert type were independent predictive factors related to response to DOS(odds ratio=4.631,1.027 and 7.639,respectively;all P<0.05).The nomogram developed with these independent factors showed an excellent performance to predict response to DOS in the TC and VC(C-index:0.838 and 0.824),with area under the receiver operating characteristic curve of 0.838 and 0.824,respectively.The calibration curves showed that the practical and predicted response to DOS effectively coincided.CONCLUSION A novel nomogram developed with pretherapeutic cT stage,GTV and Siewert type predicted the response of Siewert type II/III AEG to NAC with DOS. 展开更多
关键词 Esophagogastric junction ADENOCARCINOMA Neoadjuvant chemotherapy RESPONSE Tomography X-ray computed Predictor
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基于CUDA并行计算的煤矿奥灰突水快速准确预测方法
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作者 刘大鹏 张思睿 《承德石油高等专科学校学报》 CAS 2024年第2期9-12,59,共5页
通过分析目前我国煤矿突水预测研究的现状,提出当前条件下我国煤矿突水预测方法难以实现实时监测突水风险问题。通过将待监测区域进行有限元剖分,根据区域内钻孔水位反演计算监测区域各节点水位,从而进行突水风险预测。结合有限元突水... 通过分析目前我国煤矿突水预测研究的现状,提出当前条件下我国煤矿突水预测方法难以实现实时监测突水风险问题。通过将待监测区域进行有限元剖分,根据区域内钻孔水位反演计算监测区域各节点水位,从而进行突水风险预测。结合有限元突水预测方法,将英伟达公司开发的CUDA并行计算技术应用到煤矿突水防治中,详细介绍了CUDA预测突水软件编写思路和模型。编写了CUDA监测突水程序并结合钻孔水位数据对煤矿突水点进行了实际预测,与传统CPU串行计算相比,大大提高了煤矿突水预测计算速度,对实现煤矿突水快速准确预测具有参考意义。 展开更多
关键词 煤矿 cuda 并行计算 突水
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Optimized CUDA Implementation to Improve the Performance of Bundle Adjustment Algorithm on GPUs
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作者 Pranay R. Kommera Suresh S. Muknahallipatna John E. McInroy 《Journal of Software Engineering and Applications》 2024年第4期172-201,共30页
The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its p... The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its performance by implementing the algorithm on GPUs. In the previous research work, “Improving Accuracy and Computational Burden of Bundle Adjustment Algorithm using GPUs,” the authors demonstrated first the Bundle Adjustment algorithmic performance improvement by reducing the mean square error using an additional radial distorting parameter and explicitly computed analytical derivatives and reducing the computational burden of the Bundle Adjustment algorithm using GPUs. The naïve implementation of the CUDA code, a speedup of 10× for the largest dataset of 13,678 cameras, 4,455,747 points, and 28,975,571 projections was achieved. In this paper, we present the optimization of the Bundle Adjustment algorithm CUDA code on GPUs to achieve higher speedup. We propose a new data memory layout for the parameters in the Bundle Adjustment algorithm, resulting in contiguous memory access. We demonstrate that it improves the memory throughput on the GPUs, thereby improving the overall performance. We also demonstrate an increase in the computational throughput of the algorithm by optimizing the CUDA kernels to utilize the GPU resources effectively. A comparative performance study of explicitly computing an algorithm parameter versus using the Jacobians instead is presented. In the previous work, the Bundle Adjustment algorithm failed to converge for certain datasets due to several block matrices of the cameras in the augmented normal equation, resulting in rank-deficient matrices. In this work, we identify the cameras that cause rank-deficient matrices and preprocess the datasets to ensure the convergence of the BA algorithm. Our optimized CUDA implementation achieves convergence of the Bundle Adjustment algorithm in around 22 seconds for the largest dataset compared to 654 seconds for the sequential implementation, resulting in a speedup of 30×. Our optimized CUDA implementation presented in this paper has achieved a 3× speedup for the largest dataset compared to the previous naïve CUDA implementation. 展开更多
关键词 Scene Reconstruction Bundle Adjustment LEVENBERG-MARQUARDT Non-Linear Least Squares Memory Throughput Computational Throughput Contiguous Memory Access cuda Optimization
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基于指令流水线的CUDA核函数时间预测模型
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作者 张建定 陈根浪 明宗禹 《软件工程》 2024年第10期74-78,共5页
对CUDA核函数(CUDA Kernel Function)在静态下的评估预测是任务调度与程序优化的一个关键组成部分。文章通过对CUDA核函数的PTX(Parallel Thread Execution)进行代码分析和特性建模,精心设计了一个时间预测模型。该模型基于指令流水线... 对CUDA核函数(CUDA Kernel Function)在静态下的评估预测是任务调度与程序优化的一个关键组成部分。文章通过对CUDA核函数的PTX(Parallel Thread Execution)进行代码分析和特性建模,精心设计了一个时间预测模型。该模型基于指令流水线的原理,可以在不执行程序的情况下,预测核函数在给定硬件环境下的执行时间。实验结果表明,该模型在预测CUDA核函数执行时间上的平均百分比误差为22.87%。这意味着该模型能够相对准确地预测核函数的执行时间,为任务调度系统提供参考,并辅助开发人员对程序进行优化。 展开更多
关键词 cuda 时间预测 静态 PTX 流水线
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Simultaneous fluorescence and Compton scattering computed tomography based on linear polarization X-ray
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作者 Zhi-Jun Chi Hong-Ze Zhang +7 位作者 Jin Lin Xuan-Qi Zhang Hao Ding Qi-Li Tian Zhi Zhang Ying-Chao Du Wen-Hui Huang Chuan-Xiang Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期41-50,共10页
Purpose To propose a method for simultaneous fluorescence and Compton scattering computed tomography by using linearly polarized X-rays.Methods Monte Carlo simulations were adopted to demonstrate the feasibility of th... Purpose To propose a method for simultaneous fluorescence and Compton scattering computed tomography by using linearly polarized X-rays.Methods Monte Carlo simulations were adopted to demonstrate the feasibility of the proposed method.In the simulations,the phantom is a polytetrafluoroethylene cylinder inside which are cylindrical columns containing aluminum,water,and gold(Au)-loaded water solutions with Au concentrations ranging between 0.5 and 4.0 wt%,and a parallel-hole collimator imaging geometry was adopted.The light source was modeled based on a Thomson scattering X-ray source.The phantom images for both imaging modalities were reconstructed using a maximumlikelihood expectation maximization algorithm.Results Both the X-ray fluorescence computed tomography(XFCT)and Compton scattering computed tomography(CSCT)images of the phantom were accurately reconstructed.A similar attenuation contrast problem for the different cylindrical columns in the phantom can be resolved in the XFCT and CSCT images.The interplay between XFCT and CSCT was analyzed,and the contrast-to-noise ratio(CNR)of the reconstruction was improved by correcting for the mutual influence between the two imaging modalities.Compared with K-edge subtraction imaging,XFCT exhibits a CNR advantage for the phantom.Conclusion Simultaneous XFCT and CSCT can be realized by using linearly polarized X-rays.The synergy between the two imaging modalities would have an important application in cancer radiation therapy. 展开更多
关键词 X-ray fluorescence computed tomography Compton scattering computed tomography Linear polarization Thomson scattering X-ray source Monte Carlo simulation
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A deep learning model based on contrast-enhanced computed tomography for differential diagnosis of gallbladder carcinoma
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作者 Fei Xiang Qing-Tao Meng +4 位作者 Jing-Jing Deng Jie Wang Xiao-Yuan Liang Xing-Yu Liu Sheng Yan 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第4期376-384,共9页
Background:Gallbladder carcinoma(GBC)is highly malignant,and its early diagnosis remains difficult.This study aimed to develop a deep learning model based on contrast-enhanced computed tomography(CT)images to assist r... Background:Gallbladder carcinoma(GBC)is highly malignant,and its early diagnosis remains difficult.This study aimed to develop a deep learning model based on contrast-enhanced computed tomography(CT)images to assist radiologists in identifying GBC.Methods:We retrospectively enrolled 278 patients with gallbladder lesions(>10 mm)who underwent contrast-enhanced CT and cholecystectomy and divided them into the training(n=194)and validation(n=84)datasets.The deep learning model was developed based on ResNet50 network.Radiomics and clinical models were built based on support vector machine(SVM)method.We comprehensively compared the performance of deep learning,radiomics,clinical models,and three radiologists.Results:Three radiomics features including LoG_3.0 gray-level size zone matrix zone variance,HHL firstorder kurtosis,and LHL gray-level co-occurrence matrix dependence variance were significantly different between benign gallbladder lesions and GBC,and were selected for developing radiomics model.Multivariate regression analysis revealed that age≥65 years[odds ratios(OR)=4.4,95%confidence interval(CI):2.1-9.1,P<0.001],lesion size(OR=2.6,95%CI:1.6-4.1,P<0.001),and CA-19-9>37 U/mL(OR=4.0,95%CI:1.6-10.0,P=0.003)were significant clinical risk factors of GBC.The deep learning model achieved the area under the receiver operating characteristic curve(AUC)values of 0.864(95%CI:0.814-0.915)and 0.857(95%CI:0.773-0.942)in the training and validation datasets,which were comparable with radiomics,clinical models and three radiologists.The sensitivity of deep learning model was the highest both in the training[90%(95%CI:82%-96%)]and validation[85%(95%CI:68%-95%)]datasets.Conclusions:The deep learning model may be a useful tool for radiologists to distinguish between GBC and benign gallbladder lesions. 展开更多
关键词 Gallbladder carcinoma computed tomography Deep learning Radiomics
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Contribution of Computed Tomography to the Diagnosis of Urinary Lithiasis in a West African University Hospital
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作者 Some Milckisédek Judicaël Marouruana Tankoano Aïda Ida +5 位作者 Ouedraogo Pakisba Ali Tonde Kouka François Dassis Kindo Bassirou Zanga Soré Moussa Ouedraogo Nina-Astrid Bamouni Yomboé Abel 《Open Journal of Radiology》 2024年第2期25-32,共8页
Introduction: Urinary lithiasis is defining as a condition characterized by the formation of concretions in the kidneys or urinary excretory tract. We aimed to study professional practice in CT urinary lithiasis at CH... Introduction: Urinary lithiasis is defining as a condition characterized by the formation of concretions in the kidneys or urinary excretory tract. We aimed to study professional practice in CT urinary lithiasis at CHUYO. Materials and method: This was a descriptive cross-sectional study with retrospective data collection covering 3 years from January 2017 to December 2019. Results: In general, it was noted that CT scans in our environment provide all the elements needed by urologists to diagnose urinary lithiasis and its impact on the urinary system. However, there are shortcomings, particularly in terms of the accuracy of the shape and density of the stones in the CT scan reports, which does not make it easier for urologists to decide on treatment. Conclusion: Computed tomography plays a major role in the diagnosis and therapeutic management of urinary lithiasis, and its use needs to be improved in our context. 展开更多
关键词 computed Tomography Urinary Lithiasis DIAGNOSIS CHUYO
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The diagnostic yield for computed tomography pulmonary angiography in patients with anticoagulation
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作者 Payush Chatta Brian Diep +4 位作者 Jakrin Kewcharoen Daniel Rossie Cory Toomasian Purvi Parwani Dmitry Abramov 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第4期251-255,共5页
BACKGROUND:Patients who present to the emergency department(ED)for suspected pulmonary embolism(PE)are often on active oral anticoagulation(AC).However,the diagnostic yield of computed tomography pulmonary angiography... BACKGROUND:Patients who present to the emergency department(ED)for suspected pulmonary embolism(PE)are often on active oral anticoagulation(AC).However,the diagnostic yield of computed tomography pulmonary angiography(CTPA)in screening for PE in patients who present on AC has not been well characterized.We aim to investigate the diagnostic yield of CTPA in diagnosing PE depending on AC status.METHODS:We reviewed and analyzed the electronic medical records of patients who underwent CTPA for PE at a university hospital ED from June 1,2019,to March 25,2022.Primary outcome was the incidence of PE on CTPA depending on baseline AC status and indication for AC.RESULTS:Of 2,846 patients,242 were on AC for a history of venous thromboembolism(VTE),210 were on AC for other indications,and 2,394 were not on AC.The incidence of PE on CTPA was significantly lower in patients on AC for other indications(5.7%)when compared to patients on AC for prior VTE(24.3%)and patients not on AC at presentation(9.8%)(P<0.001).In multivariable analysis among the whole cohort,AC was associated with a positive CTPA(odds ratio[OR]0.26,95%confidence interval[CI]:0.15-0.45,P<0.001).CONCLUSION:The incidence of PE among patients undergoing CTPA in the ED is lower in patients previously on AC for indications other than VTE when compared to those not on AC or those on AC for history of VTE.AC status and indication for AC may affect pre-test probability of a positive CTPA,and AC status therefore warrants consideration as part of future diagnostic algorithms among patients with suspected PE. 展开更多
关键词 Pulmonary embolism computed tomography pulmonary angiography Emergency department ANTICOAGULATION
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Developing a Clang Libtooling-Based Refactoring Tool for CUDA GPU Programming
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作者 Kian Nejadfard Janche Sang 《Journal of Software Engineering and Applications》 2024年第2期89-108,共20页
Refactoring tools, whether fully automated or semi-automated, are essential components of the software development life cycle. As software libraries and frameworks evolve over time, it’s crucial for programs utilizin... Refactoring tools, whether fully automated or semi-automated, are essential components of the software development life cycle. As software libraries and frameworks evolve over time, it’s crucial for programs utilizing them to also evolve to remain compatible with modern advancements. Take, for example, NVIDIA CUDA’s platform for general-purpose GPU programming. Embracing the more contemporary unified memory architecture offers several benefits, such as simplifying program source code, reducing bugs stemming from manual memory management between host and device memory, and optimizing memory transfer through automated memory handling. This paper describes our development of a refactoring tool based on Clang’s Libtooling to facilitate this transition automatically, thereby relieving developers from the burden and risks associated with manually refactoring large code bases. 展开更多
关键词 REFACTORING cuda Unified Memory Clang Libtooling
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Optimizing Memory Access Efficiency in CUDA Kernel via Data Layout Technique
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作者 Neda Seifi Abdullah Al-Mamun 《Journal of Computer and Communications》 2024年第5期124-139,共16页
Over the past decade, Graphics Processing Units (GPUs) have revolutionized high-performance computing, playing pivotal roles in advancing fields like IoT, autonomous vehicles, and exascale computing. Despite these adv... Over the past decade, Graphics Processing Units (GPUs) have revolutionized high-performance computing, playing pivotal roles in advancing fields like IoT, autonomous vehicles, and exascale computing. Despite these advancements, efficiently programming GPUs remains a daunting challenge, often relying on trial-and-error optimization methods. This paper introduces an optimization technique for CUDA programs through a novel Data Layout strategy, aimed at restructuring memory data arrangement to significantly enhance data access locality. Focusing on the dynamic programming algorithm for chained matrix multiplication—a critical operation across various domains including artificial intelligence (AI), high-performance computing (HPC), and the Internet of Things (IoT)—this technique facilitates more localized access. We specifically illustrate the importance of efficient matrix multiplication in these areas, underscoring the technique’s broader applicability and its potential to address some of the most pressing computational challenges in GPU-accelerated applications. Our findings reveal a remarkable reduction in memory consumption and a substantial 50% decrease in execution time for CUDA programs utilizing this technique, thereby setting a new benchmark for optimization in GPU computing. 展开更多
关键词 Data Layout Optimization cuda Performance Optimization GPU Memory Optimization Dynamic Programming Matrix Multiplication Memory Access Pattern Optimization in cuda
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Whole-volume histogram analysis of spectral-computed tomography iodine maps characterizes HER2 expression in gastric cancer
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作者 Wei-Ling Zhang Jing Sun +8 位作者 Rong-Fang Huang Yi Zeng Shu Chen Xiao-Peng Wang Jin-Hu Chen Yun-Bin Chen Chun-Su Zhu Zai-Sheng Ye You-Ping Xiao 《World Journal of Gastroenterology》 SCIE CAS 2024年第38期4211-4220,共10页
BACKGROUND Although surgery remains the primary treatment for gastric cancer(GC),the identification of effective alternative treatments for individuals for whom surgery is unsuitable holds significance.HER2 overexpres... BACKGROUND Although surgery remains the primary treatment for gastric cancer(GC),the identification of effective alternative treatments for individuals for whom surgery is unsuitable holds significance.HER2 overexpression occurs in approximately 15%-20%of advanced GC cases,directly affecting treatment-related decisions.Spectral-computed tomography(sCT)enables the quantification of material compositions,and sCT iodine concentration parameters have been demonstrated to be useful for the diagnosis of GC and prediction of its invasion depth,angioge-nesis,and response to systemic chemotherapy.No existing report describes the prediction of GC HER2 status through histogram analysis based on sCT iodine maps(IMs).AIM To investigate whether whole-volume histogram analysis of sCT IMs enables the prediction of the GC HER2 status.METHODS This study was performed with data from 101 patients with pathologically confirmed GC who underwent preoperative sCT examinations.Nineteen parameters were extracted via sCT IM histogram analysis:The minimum,maximum,mean,standard deviation,variance,coefficient of variation,skewness,kurtosis,entropy,percentiles(1st,5th,10th,25th,50th,75th,90th,95th,and 99th),and lesion volume.Spearman correlations of the parameters with the HER2 status and clinicopathological parameters were assessed.Receiver operating characteristic curves were used to evaluate the parameters’diagnostic performance.RESULTS Values for the histogram parameters of the maximum,mean,standard deviation,variance,entropy,and percentiles were significantly lower in the HER2+group than in the HER2–group(all P<0.05).The GC differentiation and Lauren classification correlated significantly with the HER2 status of tumor tissue(P=0.001 and 0.023,respectively).The 99th percentile had the largest area under the curve for GC HER2 status identification(0.740),with 76.2%,sensitivity,65.0%specificity,and 67.3%accuracy.All sCT IM histogram parameters correlated positively with the GC HER2 status(r=0.237-0.337,P=0.001-0.017).CONCLUSION Whole-lesion histogram parameters derived from sCT IM analysis,and especially the 99th percentile,can serve as imaging biomarkers of HER2 overexpression in GC. 展开更多
关键词 Gastric cancer Spectral computed tomography Iodine map Histogram analysis
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Computed tomography imaging and clinical significance of bacterium-positive pulmonary tuberculosis complicated with diabetes
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作者 Xue-Song Rong Chao Yao 《World Journal of Clinical Cases》 SCIE 2024年第20期4230-4238,共9页
BACKGROUND The increasing prevalence of tuberculosis(TB)and diabetes on a global scale poses a significant health challenge,particularly due to their co-occurrence,which amplifies the severity,recurrence and mortality... BACKGROUND The increasing prevalence of tuberculosis(TB)and diabetes on a global scale poses a significant health challenge,particularly due to their co-occurrence,which amplifies the severity,recurrence and mortality rates associated with both conditions.This highlights the need for further investigation into their interrelationship.AIM To explore the computed tomography(CT)imaging and clinical significance of bacterium-positive pulmonary TB(PTB)combined with diabetes.METHODS There were 50 patients with bacterium-positive PTB and diabetes,and 50 with only bacterium-positive PTB.The latter were designated as the control group.The CT imaging of the two groups of patients was compared,including lesion range,shape,density and calcification.RESULTS No significant differences were observed in age,gender,smoking and drinking history,high blood pressure,hyperlipidemia and family genetic factors between the groups.However,compared to the patients diagnosed solely with simple bacterium-positive PTB,those with concurrent diabetes showed a wider range of lesions and more complex and diverse morphology on CT images.Among them,intrapulmonary tuberculosis lesions were often accompanied by manifestations of pulmonary infection,such as cavity formation and bronchiectasis.At the same time,diabetes-related signs were often seen on CT images,such as pulmonary infection combined with diabetic pulmonary lesions.Logistic regression analysis identified age and medical history as significant factors influencing the degree of pulmonary infection and CT imaging outcomes in patients with both TB and diabetes.This suggests that older age and specific medical histories may increase the risk or severity of pulmonary damage in these patients.CONCLUSION CT imaging reveals more complex lesions in PTB patients with diabetes,emphasizing the need for careful evaluation and comprehensive analysis to enhance diagnostic accuracy. 展开更多
关键词 Bacteria-positive pulmonary tuberculosis DIABETES computed tomography BRONCHIECTASIS
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Computed tomography radiogenomics:A potential tool for prediction of molecular subtypes in gastric stromal tumor
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作者 Xiao-Nan Yin Zi-Hao Wang +6 位作者 Li Zou Cai-Wei Yang Chao-Yong Shen Bai-Ke Liu Yuan Yin Xi-Jiao Liu Bo Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1296-1308,共13页
BACKGROUND Preoperative knowledge of mutational status of gastrointestinal stromal tumors(GISTs)is essential to guide the individualized precision therapy.AIM To develop a combined model that integrates clinical and c... BACKGROUND Preoperative knowledge of mutational status of gastrointestinal stromal tumors(GISTs)is essential to guide the individualized precision therapy.AIM To develop a combined model that integrates clinical and contrast-enhanced computed tomography(CE-CT)features to predict gastric GISTs with specific genetic mutations,namely KIT exon 11 mutations or KIT exon 11 codons 557-558 deletions.METHODS A total of 231 GIST patients with definitive genetic phenotypes were divided into a training dataset and a validation dataset in a 7:3 ratio.The models were constructed using selected clinical features,conventional CT features,and radiomics features extracted from abdominal CE-CT images.Three models were developed:ModelCT sign,modelCT sign+rad,and model CTsign+rad+clinic.The diagnostic performance of these models was evaluated using receiver operating characteristic(ROC)curve analysis and the Delong test.RESULTS The ROC analyses revealed that in the training cohort,the area under the curve(AUC)values for model_(CT sign),model_(CT sign+rad),and modelCT_(sign+rad+clinic)for predicting KIT exon 11 mutation were 0.743,0.818,and 0.915,respectively.In the validation cohort,the AUC values for the same models were 0.670,0.781,and 0.811,respectively.For predicting KIT exon 11 codons 557-558 deletions,the AUC values in the training cohort were 0.667,0.842,and 0.720 for model_(CT sign),model_(CT sign+rad),and modelCT_(sign+rad+clinic),respectively.In the validation cohort,the AUC values for the same models were 0.610,0.782,and 0.795,respectively.Based on the decision curve analysis,it was determined that the model_(CT sign+rad+clinic)had clinical significance and utility.CONCLUSION Our findings demonstrate that the combined modelCT_(sign+rad+clinic)effectively distinguishes GISTs with KIT exon 11 mutation and KIT exon 11 codons 557-558 deletions.This combined model has the potential to be valuable in assessing the genotype of GISTs. 展开更多
关键词 Gastrointestinal stromal tumor Radiomics Gene mutation computed tomography MODEL
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Constructing a nomogram to predict overall survival of colon cancer based on computed tomography characteristics and clinicopathological factors
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作者 Zhe-Xing Hu Yin Li +6 位作者 Xuan Yang Yu-Xia Li Yao-Yao He Xiao-Hui Niu Ting-Ting Nie Xiao-Fang Guo Zi-Long Yuan 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4104-4114,共11页
BACKGROUND The colon cancer prognosis is influenced by multiple factors,including clinical,pathological,and non-biological factors.However,only a few studies have focused on computed tomography(CT)imaging features.The... BACKGROUND The colon cancer prognosis is influenced by multiple factors,including clinical,pathological,and non-biological factors.However,only a few studies have focused on computed tomography(CT)imaging features.Therefore,this study aims to predict the prognosis of patients with colon cancer by combining CT imaging features with clinical and pathological characteristics,and establishes a nomogram to provide critical guidance for the individualized treatment.AIM To establish and validate a nomogram to predict the overall survival(OS)of patients with colon cancer.METHODS A retrospective analysis was conducted on the survival data of 249 patients with colon cancer confirmed by surgical pathology between January 2017 and December 2021.The patients were randomly divided into training and testing groups at a 1:1 ratio.Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors associated with OS,and a nomogram model was constructed for the training group.Survival curves were calculated using the Kaplan–Meier method.The concordance index(C-index)and calibration curve were used to evaluate the nomogram model in the training and testing groups.RESULTS Multivariate logistic regression analysis revealed that lymph node metastasis on CT,perineural invasion,and tumor classification were independent prognostic factors.A nomogram incorporating these variables was constructed,and the C-index of the training and testing groups was 0.804 and 0.692,respectively.The calibration curves demonstrated good consistency between the actual values and predicted probabilities of OS.CONCLUSION A nomogram combining CT imaging characteristics and clinicopathological factors exhibited good discrimination and reliability.It can aid clinicians in risk stratification and postoperative monitoring and provide important guidance for the individualized treatment of patients with colon cancer. 展开更多
关键词 Colon cancer NOMOGRAM Prognosis Overall survival computed tomography CLINICOPATHOLOGY
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