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U-Net Models for Representing Wind Stress Anomalies over the Tropical Pacific and Their Integrations with an Intermediate Coupled Model for ENSO Studies 被引量:1
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作者 Shuangying Du Rong-Hua Zhang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1403-1416,共14页
El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been develope... El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been developed to simulate and predict it.In some simplified coupled ocean-atmosphere models,the relationship between sea surface temperature(SST)anomalies and wind stress(τ)anomalies can be constructed by statistical methods,such as singular value decomposition(SVD).In recent years,the applications of artificial intelligence(AI)to climate modeling have shown promising prospects,and the integrations of AI-based models with dynamical models are active areas of research.This study constructs U-Net models for representing the relationship between SSTAs andτanomalies in the tropical Pacific;the UNet-derivedτmodel,denoted asτUNet,is then used to replace the original SVD-basedτmodel of an intermediate coupled model(ICM),forming a newly AI-integrated ICM,referred to as ICM-UNet.The simulation results obtained from ICM-UNet demonstrate their ability to represent the spatiotemporal variability of oceanic and atmospheric anomaly fields in the equatorial Pacific.In the ocean-only case study,theτUNet-derived wind stress anomaly fields are used to force the ocean component of the ICM,the results of which also indicate reasonable simulations of typical ENSO events.These results demonstrate the feasibility of integrating an AI-derived model with a physics-based dynamical model for ENSO modeling studies.Furthermore,the successful integration of the dynamical ocean models with the AI-based atmospheric wind model provides a novel approach to ocean-atmosphere interaction modeling studies. 展开更多
关键词 U-Net models wind stress anomalies ICM integration of AI and physical components
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Geochemical Anomalies Identified by Multifractal Modeling: Implications for Mineral Exploration in the Ziyoutun Cu-Au District, Jilin Province, China
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作者 MA Huchao WANG Da +3 位作者 BAI Feng LIU Meng GONG Anzhou HU Haiyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期1111-1124,共14页
The Ziyoutun Cu-Au district is located in the Jizhong–Yanbian Metallogenic Belt and possesses excellent prospects. However, the thick regolith and complex tectonic settings present challenges in terms of detecting an... The Ziyoutun Cu-Au district is located in the Jizhong–Yanbian Metallogenic Belt and possesses excellent prospects. However, the thick regolith and complex tectonic settings present challenges in terms of detecting and decomposition of weak geochemical anomalies. To address this challenge, we initially conducted a comprehensive analysis of 1:10,000-scale soil geochemical data. This analysis included multivariate statistical techniques, such as correlation analysis, R-mode cluster analysis, Q–Q plots and factor analysis. Subsequently, we decomposed the geochemical anomalies, identifying weak anomalies using spectrum-area modeling and local singularity analysis. The results indicate that the assemblage of Au-Cu-Bi-As-Sb represents the mineralization at Ziyoutun. In comparison to conventional methods, spectrumarea modeling and local singularity analysis outperform in terms of identification of anomalies. Ultimately, we considered four specific target areas(AP01, AP02, AP03 and AP04) for future exploration, based on geochemical anomalies and favorable geological factors. Within AP01 and AP02, the geochemical anomalies suggest potential mineralization at depth, whereas in AP03 and AP04 the surface anomalies require additional geological investigation. Consequently, we recommend conducting drilling, following more extensive surface fieldwork, at the first two targets and verifying surface anomalies in the last two targets. We anticipate these findings will significantly enhance future exploration in Ziyoutun. 展开更多
关键词 geochemical anomalies multivariate statistical analysis spectrum-area model local singularity analysis mineral prospecting Jilin Province
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Preliminary geological interpretation of long-wavelength magnetic anomalies over China and surrounding regions
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作者 Jie Wang YanYan Yang +4 位作者 ZhiMa Zeren Jian Wang Xin Wang YuXin Luo XuHui Shen 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期445-458,共14页
Long-wavelength(>500 km)magnetic anomalies originating in the lithosphere were first found in satellite magnetic surveys.Compared to the striking magnetic anomalies around the world,the long-wavelength magnetic ano... Long-wavelength(>500 km)magnetic anomalies originating in the lithosphere were first found in satellite magnetic surveys.Compared to the striking magnetic anomalies around the world,the long-wavelength magnetic anomalies in China and surrounding regions are relatively weak.Specialized research on each of these anomalies has been quite inadequate;their geological origins remain unclear,in particular their connection to tectonic activity in the Chinese and surrounding regions.We focus on six magnetic high anomalies over the(1)Tarim Basin,(2)Sichuan Basin(3)Great Xing’an Range,(4)Barmer Basin,(5)Central Myanmar Basin,and(6)Sunda and Banda Arcs,and a striking magnetic low anomaly along the southern part of the Himalayan-Tibetan Plateau.We have analyzed their geological origins by reviewing related research and by detailed comparison with geological results.The tectonic backgrounds for these anomalies belong to two cases:either ancient basin basement,or subduction-collision zone.However,the geological origins of large-scale regional magnetic anomalies are always subject to dispute,mainly because of limited surface exposure of sources,later tectonic destruction,and superposition of multi-phase events. 展开更多
关键词 long-wavelength magnetic anomaly lithospheric magnetic anomaly lithospheric magnetic field model satellite magnetic survey CSES
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A VGGNet-based correction for satellite altimetry-derived gravity anomalies to improve the accuracy of bathymetry to depths of 6500 m
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作者 Xiaolun Chen Xiaowen Luo +6 位作者 Ziyin Wu Xiaoming Qin Jihong Shang Huajun Xu Bin Li Mingwei Wang Hongyang Wan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期112-122,共11页
Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the... Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey data.In this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep learning.To apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more accurate.After obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth correlation.We choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the model.The experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high correlation.The standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent years.The evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous research.Finally,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results. 展开更多
关键词 gravity anomaly bathymetry inversion VGGNet multibeam sonar satellite altimetry
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A method for extracting the preseismic gravity anomalies over the Tibetan Plateau based on the maximum shear strain using GRACE data
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作者 Hui Wang DongMei Song +1 位作者 XinJian Shan Bin Wang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第4期589-608,共20页
The occurrence of earthquakes is closely related to the crustal geotectonic movement and the migration of mass,which consequently cause changes in gravity.The Gravity Recovery And Climate Experiment(GRACE)satellite da... The occurrence of earthquakes is closely related to the crustal geotectonic movement and the migration of mass,which consequently cause changes in gravity.The Gravity Recovery And Climate Experiment(GRACE)satellite data can be used to detect gravity changes associated with large earthquakes.However,previous GRACE satellite-based seismic gravity-change studies have focused more on coseismic gravity changes than on preseismic gravity changes.Moreover,the noise of the north–south stripe in GRACE data is difficult to eliminate,thereby resulting in the loss of some gravity information related to tectonic activities.To explore the preseismic gravity anomalies in a more refined way,we first propose a method of characterizing gravity variation based on the maximum shear strain of gravity,inspired by the concept of crustal strain.The offset index method is then adopted to describe the gravity anomalies,and the spatial and temporal characteristics of gravity anomalies before earthquakes are analyzed at the scales of the fault zone and plate,respectively.In this work,experiments are carried out on the Tibetan Plateau and its surrounding areas,and the following findings are obtained:First,from the observation scale of the fault zone,we detect the occurrence of large-area gravity anomalies near the epicenter,oftentimes about half a year before an earthquake,and these anomalies were distributed along the fault zone.Second,from the observation scale of the plate,we find that when an earthquake occurred on the Tibetan Plateau,a large number of gravity anomalies also occurred at the boundary of the Tibetan Plateau and the Indian Plate.Moreover,the aforementioned experiments confirm that the proposed method can successfully capture the preseismic gravity anomalies of large earthquakes with a magnitude of less than 8,which suggests a new idea for the application of gravity satellite data to earthquake research. 展开更多
关键词 Gravity Recovery And Climate Experiment(GRACE)data maximum shear strain offset index K preseismic gravity anomalies Tibetan Plateau fault zone
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High Prevalence of Anatomical Variations and Anomalies of the Coronary Arteries Detected by CT Angiography in Symptomatic Patients
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作者 Ghazi A.Alshumrani 《Congenital Heart Disease》 SCIE 2024年第2期197-206,共10页
Objective:Coronary artery anatomical variations and anomalies are an important topic due to their potential clinical manifestations.This study aims to investigate the prevalence of coronary artery anatomical variation... Objective:Coronary artery anatomical variations and anomalies are an important topic due to their potential clinical manifestations.This study aims to investigate the prevalence of coronary artery anatomical variations and anomalies in symptomatic patients with coronary computed tomography angiography(CCTA).Methods:This is a retrospective study that included all symptomatic patients who had CCTA in a tertiary care hospital in Saudi Arabia during a period of seven years.Results:The total number of included patients was 507(60%males)with a mean age of 57.4 years.Approximately 41%had luminal stenoses,averaging 49.7%.The total num-ber of patients with coronary anatomical variations(CAV)and coronary artery anomalies(CAA)was 217(43%).CAV prevalence was 26%,which included 14%non-right coronary dominance,5%short left main coronary artery(LMCA),and 7%division variations(trifurcation and quadrifurcarion)of the LMCA.The prevalence of CAA was 29%,which included 5%origin anomalies,22%myocardial bridge,and 2%course anomalies.Conclusions:A high prevalence of coronary artery anatomic variations and anomalies in symptomatic patients is reported in this study.Systematic reviews,meta-analyses,reporting guidelines,and unified definitions and classifications of cor-onary variations and anomalies are lacking in the literature,presenting potential opportunities for future research and publications. 展开更多
关键词 Coronary artery anomalies coronary anatomical variation coronary CT angiography
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Analysis of Summer Cold Vortex Activity Anomalies in Northeastern China and Their Relationship with Regional Precipitation and Temperature
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作者 孔阳 卢楚翰 +1 位作者 李凯丽 沈逸辰 《Journal of Tropical Meteorology》 SCIE 2024年第2期180-188,共9页
The Northeastern China cold vortex(NCCV)is one type of strong cyclonic vortex that occurs near Northeastern China(NEC),and NCCV activities are typically accompanied by a series of hazardous weather.This paper employed... The Northeastern China cold vortex(NCCV)is one type of strong cyclonic vortex that occurs near Northeastern China(NEC),and NCCV activities are typically accompanied by a series of hazardous weather.This paper employed an automatic algorithm to identify the NCCVs from 1979 to 2018 and analyzed their circulation patterns and climatic impacts by using the defined NCCV intensity index(NCCVI).The analysis revealed that the NCCV activities in summer exhibited a strong inter-annual variability,with an obvious periodicity of 3-4 years and 6-7 years,but without significant trends.In years when the NCCVI was high,NEC experienced negative geopotential height anomalies,cyclonic circulation,and cooler temperature anomalies,which were conducive to the maintenance and development of NCCV activities.Furthermore,large amounts of water vapor converged in NEC through two transportation routes as the NCCVs intensified,leading to a significant positive(negative)correlation with the summer precipitation(surface temperature)in NEC.The Atlantic sea surface temperature(SST)anomalies were closely related to summer NCCV activities.As the Atlantic SST rose,large amounts of surface sensible and latent heat flux were transported into the lower troposphere,inducing a positive geopotential height anomaly that occurred on the east side of the heat source.As a result,an eastward diverging flow was formed in the upper troposphere and propagated downstream,i.e.,the eastward propagating Rossby wave train,which eventually led to a coupled circulation in the Ural Mountains and NEC,as well as more intensive NCCV activities in summer. 展开更多
关键词 Northeastern China cold vortex(NCCV) ANOMALY climatic effects precipitation surface temperature development mechanisms
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Optimal timing for plastic surgical procedures for common congenital anomalies:A review
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作者 Aakanksha Goel Arun Goel 《World Journal of Clinical Pediatrics》 2024年第2期38-61,共24页
Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children... Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children born with congenital anomalies has been reported to be 3%-6%with more than 90%of these occurring in low-and middle-income group countries.The exact percentages/total numbers of children requiring surgical treatment cannot be estimated for several reasons.These children are operated under several surgical disciplines,viz,paediatric-,plastic reconstructive,neuro-,cardiothoracic-,orthopaedic surgery etc.These conditions may be life-threatening,e.g.,trachea-oesophageal fistula,critical pulmonary stenosis,etc.and require immediate surgical intervention.Some,e.g.,hydrocephalus,may need intervention as soon as the patient is fit for surgery.Some,e.g.,patent ductus arteriosus need‘wait and watch’policy up to a certain age in the hope of spontaneous recovery.Another extremely important category is that of patients where the operative intervention is done based on their age.Almost all the congenital anomalies coming under care of a plastic surgeon are operated as elective surgery(many as multiple stages of correction)at appropriate ages.There are advantages and disadvantages of intervention at different ages.In this article,we present a review of optimal timings,along with reasoning,for surgery of many of the common congenital anomalies which are treated by plastic surgeons.Obstetricians,paediatricians and general practitioners/family physicians,who most often are the first ones to come across such children,must know to guide the parents appropriately and convincingly impress upon the them as to why their child should not be operated immediately and also the consequences of too soon or too late. 展开更多
关键词 Plastic surgery Congenital anomalies Pediatric plastic surgery Facial cleft MICROTIA Vascular anomalies SYNDACTYLY HYPOSPADIAS Optimal timing Pediatric surgery
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Prevalence of Dental Anomalies among Patients Who Report to the Komfo Anokye Teaching Hospital’s Orthodontic Clinic
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作者 Ama Agyeibea Amuasi Daniel K. Sabbah +1 位作者 Alexander Oti-Achempong Rahman N. Mamah 《Open Journal of Stomatology》 2024年第2期103-117,共15页
BACKGROUND: Dental anomalies are variations from the established well-known general anatomy and morphology of the tooth as a result of disturbances during tooth formation. They can be developmental, congenital, or acq... BACKGROUND: Dental anomalies are variations from the established well-known general anatomy and morphology of the tooth as a result of disturbances during tooth formation. They can be developmental, congenital, or acquired and may be localized to a single tooth or involve systemic conditions. AIM: To evaluate the prevalence of dental anomalies in patients who report to the Komfo Anokye Teaching Hospital (KATH) dental clinics. METHOD: A descriptive cross-sectional design was used with a sample size of 92 patients aged 18 or older, obtained through convenience sampling. Data analysis was performed using SPSS version 26.0. RESULTS: The study included 92 patients aged 18 to 72 years, with 47.8% males and 52.2% females. Dental anomalies were observed in 51.1% of participants, with a higher prevalence in females (55.3%). The most common anomalies were diastema (48.3%), impacted teeth (22.0%), dilaceration (11.9%), and peg-shaped lateral teeth (6.8%). CONCLUSION: This study highlights the importance of conducting thorough dental examinations to identify and address dental anomalies, which may have implications for treatment. Early detection and correction of these anomalies are crucial to prevent future complications. 展开更多
关键词 Dental anomalies PREVALENCE Impacted Teeth Dilaceration
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Correlation of Rainfall Anomalies in Rwanda from September to December (SOND) with Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) Events
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作者 Frank Rusanganwa Ling Zhang +2 位作者 Jonah Kazora Joseph Ndakize Sebaziga Samuel Ekwacu 《Journal of Geoscience and Environment Protection》 2024年第6期115-134,共20页
Understanding the relationship between rainfall anomalies and large-scale systems is critical for driving adaptation and mitigation strategies in socioeconomic sectors. This study therefore aims primarily to investiga... Understanding the relationship between rainfall anomalies and large-scale systems is critical for driving adaptation and mitigation strategies in socioeconomic sectors. This study therefore aims primarily to investigate the correlation between rainfall anomalies in Rwanda during the months of September to December (SOND) with the occurrences of Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) events. The study is useful for early warning and forecasting of negative effects associated with extreme rainfall anomalies across the country, using Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), the National Centers for Environmental Prediction (NCEP) National Center for Atmospheric Research (NCAR) reanalysis sea surface temperature and ERA5 reanalysis datasets, during the period of 1983-2021. Both empirical orthogonal function (EOF), correlation analysis and composite analysis were used to delineate variability, relationship and the related atmospheric circulation between Rwanda seasonal rainfall September to December (SOND) with Indian Ocean Dipole (IOD) and El-Nino Southern Oscillation (ENSO). The results for Empirical Orthogonal Function (EOF) for the reconstructed rainfall data set showed three modes. EOF-1, EOF-2 and EOF-3 with their total variance of 63.6%, 16.5% and 4.8%, Indian ocean dipole (IOD) events resulted to a strong positive correlation of rainfall anomalies and Dipole model index (DMI) (r = 0.42, p value = 0.001, DF = 37) significant at 95% confidence level. The composite analysis for the reanalysis dataset was carried out to show the circulation patterns during four different events correlated with September to December seasonal rainfall in Rwanda using T-test at 95% confidence level. Wind anomaly revealed that there was a convergence of south westerly winds and easterly wind over the study area during positive Indian Ocean Diploe (PIOD) and PIOD with El Nino concurrence event years. The finding of this study will contribute to the enhancement of SOND seasonal rainfall forecasting and the reduction of vulnerability during IOD (ENSO) event years. 展开更多
关键词 CORRELATION Rainfall anomalies Rwanda Indian Ocean Dipole El Nino Southern Oscillation
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The Tibetan Plateau bridge:Influence of remote teleconnections from extratropical and tropical forcings on climate anomalies 被引量:2
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作者 Yimin Liu Wei Yu +3 位作者 Jilan Jiang Tingting Ma Jiangyu Mao Guoxiong Wu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期28-33,共6页
本文回顾了青藏高原桥梁作用方面的最新研究进展,涉及北大西洋气候异常对春,夏亚洲季风和厄尔尼诺-南方涛动(ENSO)事件的遥相关影响,热带海洋异常和中国东部极端气候异常之间的联系以及华南春雨的季节内变化等.介绍了年际时间尺度上,冬... 本文回顾了青藏高原桥梁作用方面的最新研究进展,涉及北大西洋气候异常对春,夏亚洲季风和厄尔尼诺-南方涛动(ENSO)事件的遥相关影响,热带海洋异常和中国东部极端气候异常之间的联系以及华南春雨的季节内变化等.介绍了年际时间尺度上,冬-春季北大西洋海表温度强迫如何影响南亚季风的季节性转变以及随后ENSO事件的触发.5月份青藏高原上空显著的负感热斜压结构,为北大西洋影响亚洲季风和ENSO提供了桥梁效应,夏季北大西洋涛动与华东夏季降水变化显著相关,高原潜热在这一关系中起着桥梁作用.另一方面,这种高原桥梁效应也存在于从热带海洋异常到东亚夏季极端降水事件的连接中,以及从中纬度波列到华南春雨准双周振荡的联系中. 展开更多
关键词 青藏高原桥梁作用 遥相关 北大西洋 厄尔尼诺-南方涛动 热带对流 气候异常和极端事件
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Constraining the crustal structure under the central and western Tian Shan based on teleseismic receiver functions and gravity anomalies 被引量:3
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作者 Yonghua Li Hanhan Tang Lei Shi 《Earthquake Science》 2023年第1期1-14,共14页
The Tian Shan is a vast range that spans several countries in Asia.Understanding its evolutionary history may provide valuable insights into intracontinental orogenic dynamics.In this study,we explored the crustal cha... The Tian Shan is a vast range that spans several countries in Asia.Understanding its evolutionary history may provide valuable insights into intracontinental orogenic dynamics.In this study,we explored the crustal characteristics of the Tian Shan and their relationships to the tectonic evolution of the region.A new H-stacking method that combines the P receiver function and gravity anomalies was used to estimate the thickness and ratio of P-to S-wave velocities(Vp/Vs)for 91 broadband seismic stations in the central and western Tian Shan.Our results revealed significant lateral variations in crustal thickness and Vp/Vs.A—45-km-thick crust and an intermediate-high Vp/Vs(-1.74-1.84)were found in the Kazakh Shield and Tarim Basin,which we interpreted to indicate a mafic crystalline basement and lower crust.The central Tian Shan varied greatly in crustal thickness(40-64 km)and Vp/Vs ratio(1.65-2.00).which may be due to crustal shortening,mafic underplating,and crustal melting.In contrast,we observed a relatively thin crust(42-50 km)with an intermediate Vp/Vs ratio(-1.78)in the western Tian Shan.The differences in the crustal structures between the western and central Tian Shan imply that the Talas-Fergana Fault may be trans-lithospheric. 展开更多
关键词 Tian Shan crustal thickness crustal composition receiver function gravity anomaly
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Europium anomalies in detrital zircons reveal the crustal thickness evolution of South China in Early Neoproterozoic
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作者 Zhi Chen 《Acta Geochimica》 EI CAS CSCD 2023年第4期739-746,共8页
The South China Block(SCB)is formed by the amalgamation of the Yangtze and Cathaysia blocks during the Early Neoproterozoic along the Jiangnan Orogen.However,the precise amalgamation time of these two blocks and the l... The South China Block(SCB)is formed by the amalgamation of the Yangtze and Cathaysia blocks during the Early Neoproterozoic along the Jiangnan Orogen.However,the precise amalgamation time of these two blocks and the location of the united SCB in the Rodinia supercontinent remain highly debatable.Various tectonic models have been proposed and they may have different implications for the crustal thickness evolution of the central SCB in Early Neoproterozoic.To evaluate these models,this paper uses a recently calibrated Eu/Eu*-inzircon proxy to reconstruct crustal thickness evolution of the central SCB during Early Neoproterozoic.I compiled and screened U–Pb ages and trace elements of 900–700 Ma detrital zircons from the central SCB and then calculated the zircon Eu/Eu*values.The age-binned average zircon Eu/Eu*displays a decreasing trend from 870 to 790 Ma,and thus indicates no significant crustal thickening event occurred during this time interval.This finding seems to be inconsistent with tectonic models that the Yangtze and Cathaysia blocks amalgamated during this time interval.Yet,given that available coupled detrital zircon U–Pb and trace element datasets are very limited,additional studies are warranted to further evaluate this hypothesis. 展开更多
关键词 South China Crustal thickness NEOPROTEROZOIC Detrital zircon Eu anomalies
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“I Dread the Heart Surgery but it Keeps My Child Alive”—Experiences of Parents of Children with Right Ventricular Outflow Tract Anomalies during the Assessment for Cardiac Reoperation
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作者 Birgitta Svensson Petru Liuba +1 位作者 Anne Wennick Malin Berghammer 《Congenital Heart Disease》 SCIE 2023年第3期349-359,共11页
Background:Parents of children with complex right ventricular outflow tract(RVOT)anomalies are confronted with their child’s need for heart surgery early in life and repeated reoperations later on.Preoperative assess... Background:Parents of children with complex right ventricular outflow tract(RVOT)anomalies are confronted with their child’s need for heart surgery early in life and repeated reoperations later on.Preoperative assessment needs to be performed whenever an indication for reoperation is suspected.The aim was to illuminate the experiences of parents of children diagnosed with RVOT anomalies,in particular,how they experience their child’s heart disease and everyday life during the assessment and after the decision on whether to perform a reoperation.Method:Individual interviews(n=27)were conducted with nine parents on three occasions between 2014 and 2016 and analyzed using reflexive thematic analysis.Results:The analysis resulted in the following five main coexisting themes:The heart surgery keeps my child alive illuminates parents’experiences during and after the assessment and emphasizes that heart surgery,although dreaded,is central for their child’s survival;Everyday struggles illuminates the different struggles parents had to face to ensure that their child would be in the best possible condition;the remaining three themes,Unconditional love,Trust in life,and Togetherness,illuminate the ways in which the parents gained inner strength and confidence in their everyday lives.Conclusion:Although the parents were grateful for the assessment and had learned to navigate among the fears it aroused,they experienced several distressing situations during the assessment process that should be addressed.By inviting both the parents and their child to participate in the child’s care,individualized support can take into account the needs of both parents and child. 展开更多
关键词 PARENTS CHILDREN right ventricular outflow tract anomalies everyday life heart surgery reflexive thematic analysis
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Penile vascular anomalies:A retrospective single center study and cumulative analysis of studies from China
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作者 Chong Ma Feng Gao +3 位作者 Ran An Yawei Guan Jingfei Teng Xing Ai 《Asian Journal of Urology》 CSCD 2023年第4期555-562,共8页
Objective Penile vascular anomalies(PVAs)or hemangioma can arouse patient concern about aesthetics and cause symptoms like bleeding and sexual dysfunction.However,its low incidence and the deficiency of large-volume s... Objective Penile vascular anomalies(PVAs)or hemangioma can arouse patient concern about aesthetics and cause symptoms like bleeding and sexual dysfunction.However,its low incidence and the deficiency of large-volume studies hinder urologists from making informed decisions.This study aimed to investigate the clinical features and treatment experience of PVAs at the Seventh Medical Center of PLA General Hospital,Beijing,China.Furthermore,by systematically analysis of studies on PVAs in Chinese people,we aimed to provide novel insights on the management of this condition.Methods We retrospectively investigated clinical features and pathology of surgery-treated PVAs at our center.Moreover,by systemically reviewing the literature from PubMed and the three largest medical databases(China National Knowledge Infrastructure,Wan Fang,and Chinese Medical Journal Database)in China,we analyzed the clinical features and various therapies of PVAs in Chinese people.Results Between March 1,2018 and March 1,2023,a total of 356 cases with vascular anomalies were treated with surgery at out center.Only seven(2.0%)cases had lesions involving the perineum and external genitalia.All the seven cases were pathologically benign and demonstrated no recurrence over a follow-up period of 1-52 months(median 14 months).A total of 410 cases from 44 studies were selected in the cumulative analysis.Most patients(92.4%)diagnosed with PVAs were asymptomatic,and 68.8%of the patients were treated with sclerotherapy.As to the pathology,57.1%were venous malformation.Conclusion The most common PVA is venous malformation and the majority of patients are asymptomatic.Sclerotherapy and laser have emerged as viable options for treating small lesions.Surgery still has its role in treating large lesions and obtaining pathology.Although PVAs often relapse or demand multiple treatments,the prognosis is favorable. 展开更多
关键词 HEMANGIOMA Laser irradiation PENIS SURGERY Vascular anomaly
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Characteristics of gravity anomalies and tectonic analysis of Enderby Land in East Antarctica and its adjacent areas
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作者 Long Ma Chenguang Liu +2 位作者 An Yang Baohua Liu Chenglong Xia 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期94-103,共10页
Enderby Land in East Antarctica and its adjacent areas,which are closely related to the Indian Plate in their geological evolution,have become one of the key zones for studies on how the Antarctic continent evolves.Ba... Enderby Land in East Antarctica and its adjacent areas,which are closely related to the Indian Plate in their geological evolution,have become one of the key zones for studies on how the Antarctic continent evolves.Based on the isostasy and flexure theories of the lithosphere and using the CRUST1.0 model as the depth constraint,this paper uses the gravity field model EIGEN-6C4 and topographic data to calculate the isostatic gravity anomalies of Enderby Land and its adjacent areas.Then,the crustal thickness of the study area is calculated,and three comprehensive geophysical interpretation profiles that vertically span the study area are plotted.The results show that the flexural isostatic gravity anomalies in Enderby Land and its adjacent areas are closely related to the regional tectonic setting,and the anomalies in different regions differ substantially,ranging from−50×10^(−5)m/s^(2)to 85×10^(−5)m/s^(2).A zone of high isostatic gravity anomalies(30×10^(−5)−80×10^(−5)m/s^(2))is distributed outside the Cooperation Sea and Queen Maud Land,which may be plate remnants generated by early rifting.Except for the Kerguelen Plateau,which was formed by a hotspot and has a crustal thickness of 15 km,the thickness of the oceanic crust in other parts of the study area changes slightly by approximately 4–9 km,with the thinnest part being in Enderby Basin.The thickness of the inland crust along the coastline increases with the elevation,with the maximum thickness reaching 34 km.The isostatic gravity anomalies corresponding to the zone of high magnetic anomalies along the continental margin of Queen Maud Land are negative and small,with an isostatic adjustment trend indicating Moho surface uplift,and those on the edge of central Enderby Land are near zero,approaching the isostatic state,which may be caused by the magmatism at the early stage of rifting.The continental-oceanic boundary should be close to the contour line of the crustal thickness 10–12 km on the outer edge of the coastline. 展开更多
关键词 Enderby Land and its adjacent areas flexural isostatic gravity anomalies crustal structure isostatic adjustment
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Predicting portal venous anomalies by left-sided gallbladder or rightsided ligamentum teres hepatis: A large scale, propensity scorematched study
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作者 Hsuan-Yin Lin Rheun-Chuan Lee +6 位作者 Jyh-Wen Chai Chiann-Yi Hsu Yen Chou Hsuen-En Hwang Chien An Liu Nai-Chi Chiu Ho-Hsian Yen 《World Journal of Gastroenterology》 SCIE CAS 2023年第27期4344-4355,共12页
BACKGROUND Right-sided ligamentum teres(RSLT)is often associated with portal venous anomalies(PVA)and is regarded as a concerning feature for hepatobiliary intervention.Most studies consider RSLT to be one of the caus... BACKGROUND Right-sided ligamentum teres(RSLT)is often associated with portal venous anomalies(PVA)and is regarded as a concerning feature for hepatobiliary intervention.Most studies consider RSLT to be one of the causes of left-sided gallbladder(LGB),leading to the hypothesis that LGB must always be present with RSLT.However,some cases have shown that right-sided gallbladder(RGB)can also be present in livers with RSLT.AIM To highlight the rare variation that RSLT may not come with LGB and to determine whether ligamentum teres(LT)or gallbladder location is reliable to predict PVA.METHODS This study retrospectively assessed 8552 contrast-enhanced abdominal computed tomography examinations from 2018 to 2021[4483 men,4069 women;mean age,59.5±16.2(SD)years].We defined the surrogate outcome as major PVAs.The cases were divided into 4 subgroups according to gallbladder and LT locations.On one hand,we analyzed PVA prevalence by LT locations using gallbladder location as a controlled variable(n=36).On the other hand,we controlled LT location and computed PVA prevalence by gallbladder locations(n=34).Finally,we investigated LT location as an independent factor of PVA by using propensity score matching(PSM)and inverse probability of treatment weighting(IPTW).RESULTS We found 9 cases of RSLT present with RGB.Among the LGB cases,RSLT is associated with significantly higher PVA prevalence than typical LT[80.0%vs 18.2%,P=0.001;OR=18,95%confidence interval(CI):2.92-110.96].When RSLT is present,we found no statistically significant difference in PVA prevalence for RGB and LGB cases(88.9%vs 80.0%,P>0.99).Both PSM and IPTW yielded balanced cohorts in demographics and gallbladder locations.The RSLT group had a significantly higher PVA prevalence after adjusted by PSM(77.3%vs 4.5%,P<0.001;OR=16.27,95%CI:2.25-117.53)and IPTW(82.5%vs 4.7%,P<0.001).CONCLUSION RSLT doesn't consistently coexist with LGB.RSLT can predict PVA independently while the gallbladder location does not serve as a sufficient predictor. 展开更多
关键词 Right-sided ligamentum teres Left-sided gallbladder Portal venous anomalies Inverse probability of treatment weighting Average treatment effect in the treated
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Gravity anomalies determined from mean sea surface model data over the Gulf of Mexico
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作者 Xuyang Wei Xin Liu +4 位作者 Zhen Li Xiaotao Chang Hongxin Luo Chengcheng Zhu Jinyun Guo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第12期39-50,共12页
With the improvements in the density and quality of satellite altimetry data,a high-precision and high-resolution mean sea surface model containing abundant information regarding a marine gravity field can be calculat... With the improvements in the density and quality of satellite altimetry data,a high-precision and high-resolution mean sea surface model containing abundant information regarding a marine gravity field can be calculated from long-time series multi-satellite altimeter data.Therefore,in this study,a method was proposed for determining marine gravity anomalies from a mean sea surface model.Taking the Gulf of Mexico(15°–32°N,80°–100°W)as the study area and using a removal-recovery method,the residual gridded deflections of the vertical(DOVs)are calculated by combining the mean sea surface,mean dynamic topography,and XGM2019e_2159 geoid,and then using the inverse Vening-Meinesz method to determine the residual marine gravity anomalies from the residual gridded DOVs.Finally,residual gravity anomalies are added to the XGM2019e_2159 gravity anomalies to derive marine gravity anomaly models.In this study,the marine gravity anomalies were estimated with mean sea surface models CNES_CLS15MSS,DTU21MSS,and SDUST2020MSS and the mean dynamic topography models CNES_CLS18MDT and DTU22MDT.The accuracy of the marine gravity anomalies derived by the mean sea surface model was assessed based on ship-borne gravity data.The results show that the difference between the gravity anomalies derived by DTU21MSS and CNES_CLS18MDT and those of the ship-borne gravity data is optimal.With an increase in the distance from the coast,the difference between the gravity anomalies derived by mean sea surface models and ship-borne gravity data gradually decreases.The accuracy of the difference between the gravity anomalies derived by mean sea surface models and those from ship-borne gravity data are optimal at a depth of 3–4 km.The accuracy of the gravity anomalies derived by the mean sea surface model is high. 展开更多
关键词 mean sea surface gravity anomaly Gulf of Mexico inverse Vening-Meinesz formula mean dynamic topography satellite altimetry
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Robust ACO-Based Landmark Matching and Maxillofacial Anomalies Classification
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作者 Dalel Ben Ismail Hela Elmannai +1 位作者 Souham Meshoul Mohamed Saber Naceur 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2219-2236,共18页
Imagery assessment is an efficient method for detecting craniofacial anomalies.A cephalometric landmark matching approach may help in orthodontic diagnosis,craniofacial growth assessment and treatment planning.Automati... Imagery assessment is an efficient method for detecting craniofacial anomalies.A cephalometric landmark matching approach may help in orthodontic diagnosis,craniofacial growth assessment and treatment planning.Automatic landmark matching and anomalies detection helps face the manual labelling lim-itations and optimize preoperative planning of maxillofacial surgery.The aim of this study was to develop an accurate Cephalometric Landmark Matching method as well as an automatic system for anatomical anomalies classification.First,the Active Appearance Model(AAM)was used for the matching process.This pro-cess was achieved by the Ant Colony Optimization(ACO)algorithm enriched with proximity information.Then,the maxillofacial anomalies were classified using the Support Vector Machine(SVM).The experiments were conducted on X-ray cephalograms of 400 patients where the ground truth was produced by two experts.The frameworks achieved a landmark matching error(LE)of 0.50±1.04 and a successful landmark matching of 89.47%in the 2 mm and 3 mm range and of 100%in the 4 mm range.The classification of anomalies achieved an accuracy of 98.75%.Compared to previous work,the proposed approach is simpler and has a comparable range of acceptable matching cost and anomaly classification.Results have also shown that it outperformed the K-nearest neigh-bors(KNN)classifier. 展开更多
关键词 Maxillofacial anomalies cephalometric landmarks similarity chi-square distance quadratic assignment problem ant colony optimization SVM
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Deep learning-based method for detecting anomalies in electromagnetic environment situation
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作者 Wei-lin Hu Lun-wen Wang +2 位作者 Chuang Peng Ran-gang Zhu Meng-bo Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期231-241,共11页
The anomaly detection of electromagnetic environment situation(EMES) has essential reference value for electromagnetic equipment behavior cognition and battlefield threat assessment.In this paper,we proposed a deep le... The anomaly detection of electromagnetic environment situation(EMES) has essential reference value for electromagnetic equipment behavior cognition and battlefield threat assessment.In this paper,we proposed a deep learning-based method for detecting anomalies in EMES to address the problem of relatively low efficiency of electromagnetic environment situation anomaly detection(EMES-AD).Firstly,the convolutional kernel extracts the static features of different regions of the EMES.Secondly,the dynamic features of the region are obtained by using a recurrent neural network(LSTM).Thirdly,the Spatio-temporal features of the region are recovered by using a de-convolutional network and then fused to predict the EMES.The structural similarity algorithm(SSIM) is used to determine whether it is anomalous.We developed the detection framework,de-signed the network parameters,simulated the data sets containing different anomalous types of EMES,and carried out the detection experiments.The experimental results show that the proposed method is effective. 展开更多
关键词 Electromagnetic environment situation(EMES) Anomaly detection(AD) Regional features integration LSTM CNN
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