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Successful treatment of an enormous rectal mucosa-associated lymphoid tissue lymphoma by endoscopic full-thickness resection:A case report

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World Journal of Gastroenterology 2022年第10期28卷 1078-1084页

作者： Fang-Yuan Li Xiao-Long zhang Qi-De Zhang Yao-Hui Wang Digestive Endoscopy Center Affiliated Hospital of Nanjing University of Chinese MedicineJiangsu Province Hospital of TCMNanjing 210046Jiangsu ProvinceChina department of Pathology Affiliated Hospital of Nanjing University of Chinese MedicineJiangsu Province Hospital of TCMNanjing 210046Jiangsu ProvinceChina

BACKGROUND Colorectal mucosa-associated lymphoid tissue lymphoma(MALToma),a rare kind of nongastric MALToma,lacks consensus on its endoscopic features and standard therapies.According to previous studies on the clinical characteristics and outcomes of colorectal MALToma,endoscopic resection remains a good therapeutic strategy.CASE SUMMARY A 71-year-old woman suffered intermittent hematochezia for 1 mo,accompanied with abdominal pains but without weight loss,fever,chills or fatigue.Colonoscopy showed a massive hemispheric mass with rough and hyperemic mucosa in the lower rectum.Narrow-band imaging magnifying endoscopy detected some branching abnormal blood vessels and disappearance of glandular structure,which was similar with the tree-like appearance sign in gastric MALToma.Endoscopic ultrasonography revealed the lesion to be hypoechoic,boundary-defined,and echo uniform inside,originating from the muscularis propria.Abdominal enhanced computed tomography(CT)demonstrated a soft tissue mass with defined boundary.No enlarged superficial lymph nodes were detected by B-mode ultrasound.C13-urea breath test and serum Helicobacter pylori antibody were both negative.The patient underwent endoscopic full-thickness resection.Postoperative pathological analysis indicated colorectal MALToma.The patient remained asymptomatic after discharge,and follow-up positron emission tomography–CT and colonoscopy showed no residual lesion,remnants or lymph node metastasis.CONCLUSION This case provides new information on the specific endoscopic features of colorectal MALToma and an alternative treatment for patients.

关键词： Mucosa-associated lymphoid tissue lymphoma Endoscopic full-thickness resection Endoscopic minimally invasive surgery Endoscopy Case report

Experiment on surface wake of internal waves generated by underwater vehicle in stratified fluids

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Journal of Hydrodynamics 2022年第2期34卷 277-285页

作者： Zhi-chong Yao Jun zhang de-bao Gao Chuan-qi Liu Fang-wen Hong China Ship Scientific Research Center Wuxi214082China TaiHu Laboratory on deep Sea Technology and Science Wuxi214082China National Key Laboratory on Ship Vibration and Noise Wuxi214082China

The surface flow field of internal waves generated by the underwater vehicle is very weak.In order to study the characteristics of the surface wake of internal waves,a surface particle image velocimetry(PIV)technique which can be used to measure the flow field in the order of mm/s is developed.Breakthrough is made with respect to the key technique measuring the micro-velocity flow field of internal waves on the water surface in stratified fluids.The wake generated by SUBOFF model is measured in stratified fluid tank,and the surface flow field of internal waves is successfully measured for the first time.The experimental results are compared with predicted results by the classical Tuck’s internal wave theory.The results show the characteristics of the surface wake signature of internal waves and the variation of the angle between internal wave beams and the surface flow velocity of internal wave with the towing speed of the model are in good agreement.It provides support for further research on wake signature remote sensing of internal waves in laboratory.

关键词： Stratified fluids surface wake signature internal waves experimental research

Robust adaptive UKF based on SVR for inertial based integrated navigation

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defence Technology（防务技术） 2020年第4期16卷 846-855页

作者： Meng-de zhang Hai-fa Dai Bai-qing Hu qi Chen College of Electrical Engineering Naval Univ.of EngineeringWuhan 430033China qingdao Brigade Shandong Branch of the Armed Police Marine Police CorpsQingdao 266033China

Aiming at the problem that the traditional Unscented Kalman Filtering(UKF) algorithm can't solve the problem that the measurement covariance matrix is unknown and the measured value contains outliers,this paper proposes a robust adaptive UKF algorithm based on Support Vector Regression(SVR).The algorithm combines the advantages of support vector regression with small samples,nonlinear learning ability and online estimation capability of adaptive algorithm based on innovation.Firstly,the SVR model is trained by using the innovation in the sliding window,and the new innovation is monitored.If the deviation between the estimated innovation and the measured innovation exceeds a given threshold,then measured innovation will be replaced by the predicted innovation,and then the processed innovation is used to calculate the measurement noise covariance matrix using the adaptive estimation algorithm.Simulation experiments and measured data experiments show that SVRUKF is significantly better than the traditional UKF,robust UKF and adaptive UKF algorithms for the case where the covariance matrix is unknown and the measured values have outliers.

关键词： Integrated navigation Support vector regression Unscented Kalman filter Robust filter Adaptive filter

Geochemistry of rare earth elements and yttrium in Late Permian coals from the Zhongliangshan coalfield, southwestern China

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Frontiers of Earth Science 2023年第1期17卷 230-250页

作者： qingfeng LU Shenjun qiN Hongyang BAI Wenfeng WANG de’e qi Xin HE Bofei zhang School of Resources and Geosciences China University of Mining&TechnologyXuzhou 221116China Key Laboratory for Resource Exploration Research of Hebei Province Hebei University of EngineeringHandan 056038China Key Laboratory of Coalbed Methane Resources&Reservoir Formation Process Ministry of EducationChina University of Mining&TechnologyXuzhou 221008China

Rare earth elements and yttrium(REY)in coal deposits are considered promising alternative sources for these resources owing to their increasing global demand.This paper reports the geochemical characteristics of REY in the Late Permian coals from an underground K1a seam section of the Zhongliangshan coalfield in Chongqing,southwestern China.The mineralogy,degree of enrichment,distribution patterns,modes of occurrence,and sediment origin of REY were investigated.Compared with the average of world coals,the concentration of REY in the K1a coals were normal,dominated by light REY(LREY),with less medium and heavy REY(MREY,HREY).The fractionation degree of the MREY and HREY are higher than that of LREY in most K1a coal samples,deduced from the mixed enrichment type of REY,mainly including M-H-type,and a few L-M type and H-type.In addition,the combination of anomalies of Ce,Eu,Gd,and Al_(2)O_(3)/TiO_(2) parameters,the terrigenous materials in the K1a coal were derived from the felsic-intermediate rocks at the top of the Emeishan basalt sequence,and the samples were affected by seawater intrusion during early peat accumulation.Although the minerals primarily consist of kaolinite,illite,pyrite,and small amounts of quartz,calcite and anatase,REY are correlated with ash yield,SiO2,and Al_(2)O_(3),revealing that the REY mainly occur in aluminosilicate minerals,especially kaolinite and illite.Meanwhile,REY positively relate to P_(2)O_(5) and Zr,which may exist in phosphate-containing minerals or zircon.Furthermore,most samples in the K1a coal or ash do not reach the cut-off grade for the beneficial recovery of REY.With the exception of central Guizhou,southwestern Chongqing,and the junction of western Guizhou and northeastern Yunnan,the REY content in coals from southwestern China are high,and its by-products are suitable as potential REY sources.

关键词： rare earth elements and yttrium Zhongliangshan K1a coal sediment source modes of occurrence geochemical characteristics

Physical and numerical investigation on fluid flow and inclusion removal behavior in a single-strand tundish

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Journal of Iron and Steel Research(International) 2023年第6期30卷 1182-1198页

作者： qi Quan Zhi-xiao zhang Tian-peng Qu Xiang-long Li Jun Tian de-yong Wang School of Iron and Steel Soochow UniversitySuzhou 215137JiangsuChina

Aiming at the problem that the existence of inclusions in the tundish continuous casting process can easily lead to quality defects of the slab,the stainless steel continuous casting tundish was taken as the research object.The effects of flow control device,inclusion density and inclusion size on the mixing characteristics of molten steel and inclusion behavior in tundish were studied.The results showed that compared with the tundish without flow control device,the average residence time of molten steel was prolonged by about 49 s,the dead zone volume fraction was reduced by 8.93%,and the piston fluid integral rate was increased by 12.68%.In the turbulence inhibitor(TI)tundish with weir-dam combination,the removal rate of inclusions with a density of 2700 kg m^(-3) and a particle size of 5 lm is 63.32%,while the removal rate of large inclusions with a density of 150μm could reach 89.04%.When the inclusion particle size was 10-50μm and the density was 2700-4500 kg m^(-3),the effect of inclusion density on inclusion removal rate was small.At the same time,when weir-dam combination TI tundish was set,the inclusions were mainly limited to the slag-metal interface of the first and second chambers of the tundish.The removal rate of inclusions in the first chamber was generally improved,with 10μm inclusions accounting for 47.67% and 150μm inclusions accounting for 60.69%.Furthermore,it has the best effect on the removal of small-size inclusions,especially those less than 70μm.

关键词： Non-metallic inclusion Flow control device Residence time distribution curve Removal behavior Discrete particle model

Prediction of high-embankment settlement combining joint denoising technique and enhanced GWO-v-SVR method

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 317-332页

作者： qi zhang qian Su Zongyu zhang Zhixing deng de Chen School of Civil Engineering Southwest Jiaotong UniversityChengduChina MOE Key Laboratory of High Speed Railway Engineering Southwest Jiaotong UniversityChengduChina

Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure safety.This study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wolf optimizer(EGWO)-n-support vector regression(n-SVR)method.High-embankment field measurements were preprocessed using the joint denoising technique,which in-cludes complete ensemble empirical mode decomposition,singular value decomposition,and wavelet packet transform.Furthermore,high-embankment settlements were predicted using the EGWO-n-SVR method.In this method,the standard gray wolf optimizer(GWO)was improved to obtain the EGWO to better tune the n-SVR model hyperparameters.The proposed NHM was then tested in two case studies.Finally,the influences of the data division ratio and kernel function on the EGWO-n-SVR forecasting performance and prediction efficiency were investigated.The results indicate that the NHM suppresses noise and restores details in high-embankment field measurements.Simultaneously,the NHM out-performs other alternative prediction methods in prediction accuracy and robustness.This demonstrates that the proposed NHM is effective in predicting high-embankment settlements with noisy field mea-surements.Moreover,the appropriate data division ratio and kernel function for EGWO-n-SVR are 7:3 and radial basis function,respectively.

关键词： High embankment Settlement prediction Joint denoising technique Enhanced gray wolf optimizer Support vector regression

Entropy production by dissipation effects and characteristic vortex evolution in a rocket turbopump

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Journal of Hydrodynamics 2023年第5期35卷 993-1007页

作者： de-you Li Jia-qi Zhu Rui-yi zhang Yi zhang Zhi-peng Li Hong-jie Wang Zhi-peng Ren School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China School of Astronautics Harbin Institute of TechnologyHarbin150001China

The relationship between entropy production and vortex evolution affects the efficiency and stability of rotating machinery.This study investigated the energy characteristics of a rocket turbopump and revealed the correlated mechanisms of the entropy production rate using the dissipation effects and characteristic vortex evolution.For the first time,direct and turbulent dissipation and rigid and shear vorticity decomposition methods were utilized to analyze the correlation between flow loss and characteristic vorticities in rotating machinery.With an increase in the flow rate,the hydraulic losses of the dissipation effects and wall decreased by 60%and 38.3%,respectively,and the proportions of the input energy decreased(from 13%to 8%)and remained stable(8%),respectively.The local direct dissipative entropy production(DdeP)in the inducer-impeller is strongly related to shear entropy,and the correlated effect of total enstrophy on DdeP is weaker than that of shear vorticity,indicating that rigid enstrophy suppresses direct dissipation.The correlation between turbulent dissipation and rigid enstrophy was significantly weaker in the static flow passage of the turbopump owing to the weak rigid rotational effect.The correlation between the rigid entropy and local turbulent dissipative entropy production(TdeP)gradually increased with increasing flow rate,reaching a medium correlation(the maximal correlated degree in the turbopump)and exhibiting rigid rotation effects on the hydraulic loss.Moreover,the flow rate significantly affected the correlation(except for the diffuser),and the two characteristic vorticities reached a maximum at the designed flow rate owing to optimal efficiency and minimum hydraulic loss.

关键词： Rocket turbopump hydraulic loss dissipation entropy production vorticity decomposition Liutex

Systematic study on the proton radioactivity of spherical proton emitters

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Nuclear Science and Techniques 2023年第4期34卷 93-101页

作者： Dong-Meng zhang Lin-Jing qi de-Xing Zhu Yang-Yang Xu Song Luo Xiao-Hua Li School of Nuclear Science and Technology University of South ChinaHengyang 421001China National Exemplary Base for International Sci&Tech.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.

关键词： Proton radioactivity Spherical nuclei Two-potential approach Modified Woods–Saxon potential Half-lives

The First Global Map of Atmospheric Ammonia(NH_(3)) as Observed by the HIRAS/FY-3D Satellite

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Advances in Atmospheric Sciences 2024年第3期41卷 379-390页

作者： Minqiang ZHOU Zhili deNG Charles ROBERT Xingying zhang Lu zhang Yapeng WANG Chengli qi Pucai WANG Martine de MAZIÈRE Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Royal Belgian Institute for Space Aeronomy(BIRA-IASB) Brussels 1180Belgium National Satellite Meteorology Center China Meteorological AdministrationBeijing 100081China department of Science&Technology and Climate Change China Meteorological AdministrationBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentration based on the absorption lines of NH_(3) in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH_(3)column from the Hyperspectral Infrared Atmospheric Sounder(HIRAS) onboard the Chinese Feng Yun(FY)-3D satellite and present the first atmospheric NH_(3) column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH_(3) hotspots around the world, e.g., India, West Africa, and East China, where large NH_(3) emissions exist. The HIRAS NH_(3) columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer(IASI)measurements, and we find that the two instruments observe a consistent NH_(3) global distribution, with correlation coefficient(R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH_(3) retrieval are discussed.

关键词： ammonia HIRAS/FY-3D satellite thermal-infrared observation remote sensing optimal estimation method