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
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
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
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
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
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
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
Background: Congenital Uterine Anomalies are malformations of the Uterus which occur during embryonic life and result from the abnormal formation, fusion or resorption of the Mullerian ducts. Most of them are asymptom...Background: Congenital Uterine Anomalies are malformations of the Uterus which occur during embryonic life and result from the abnormal formation, fusion or resorption of the Mullerian ducts. Most of them are asymptomatic and diagnosis is done incidentally or during examinations performed for other purposes. We report three cases of women with pregnancies in malformed uteri. Aim: To depict the diagnostic challenges and therapeutic aspects of management of pregnancies in congenitally malformed Uteri. Case Presentation: The first case was a 22-year-old student who came to consult for a second opinion on the management of an ectopic pregnancy. A 2D Ultrasound done prior revealed an ectopic pregnancy but failed to specify its location in a rudimentary uterine horn. Management with a Multi-dose Methotrexate regimen was initiated but progress was not favorable. She came to us for a second opinion on management. Diagnostic laparoscopy was done and revealed an ectopic pregnancy in a rudimentary uterine horn. This was confirmed by histopathology. Management consisted of resection of the rudimentary horn and a right total salpingectomy. The second case was that of a woman who presented with spotting in early pregnancy. An Obstetric 2D ultrasound done revealed a bicornuate Uterus with a Gestational sac in one horn. She was placed on progesterone supplementation for 2 weeks, with regular antenatal contacts. She had an elective cesarean section at 39 weeks. Surgery revealed a complete Bicornuate Uterus. The post-operative period was uneventful with no complications. The third case was that of a woman with a past history of five successive spontaneous abortions, who presented with spotting at about 8 weeks of gestation. An Obstetric Ultrasound done revealed a Bicornuate Uterus and an embryo in one cornus. She was admitted, given her poor obstetric history, for about 14 days and placed on progesterone supplementation till 20 weeks of gestation. Antenatal contacts were regular and she had an emergency cesarean section at 36 weeks. There were no complications in the post operative period. Conclusion: The high degree of diagnostic accuracy makes 3D ultrasound the diagnostic modality of choice. Nevertheless, 2D and Hysterosalpingography can be used as well. Management of pregnancies in women with congenital Uterine anomalies varies per case as presenting symptoms and outcomes with pregnancies are not alike. When diagnosed out of pregnancy, and depending on the type of anomaly, surgical management may be recommended.展开更多
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
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
Extreme weather anomalies such as rainfall and its subsequent flood events are governed by complex weather systems and interactions between them. It is important to understand the drivers of such events as it helps pr...Extreme weather anomalies such as rainfall and its subsequent flood events are governed by complex weather systems and interactions between them. It is important to understand the drivers of such events as it helps prepare for and mitigate or respond to the related impacts. In line with the above statements, quarter-hourly data for the year 2021 recorded in the Yaounde meteorological station were synthesized to come out with daily and dekadal (10-day averaged) anomalies of six climate factors (rainfall, temperature, insolation, relative humidity, dew point and wind speed), in order to assess the occurrences and severity of floods to changing weather patterns in Yaounde. In addition, Precipitation Concentration Index (PCI) was computed to evaluate the distribution and analyse the frequency and intensity of precipitation. Coefficient of variation (CV) was used to estimate the seasonal and annual variation of rainfall patterns, while Mann-Kendall (MK) trend test was performed to detect weather anomalies (12-month period variation) in quarter-hourly rainfall data from January 1<sup>st</sup> to December 31<sup>st</sup> 2021. The Standard Precipitation Index (SPI) was also used to quantify the rainfall deficiency of the observed time scale. Results reveal that based on the historical data from 1979 to 2018 in the bimodal rainfall forest zone, maximum and minimum temperature averages recorded in Yaounde in 2021 were mostly above historical average values. Precipitations were rare during dry seasons, with range value of 0 - 13.6 mm for the great dry season and 0 - 21.4 mm for the small dry season. Whereas during small and great rainy seasons, rainfalls were regular with intensity varying between 0 and 50 mm, and between 0 and 90.4 mm, respectively. The MK trend test showed that there was a statistical significant increase in rainfall trend for the month of August at a 5% level of significance, while a significant decreasing trend was observed in July and December. There was a strong irregular rainfall distribution during the months of February, July and December 2021, with a weather being mildly wetted during all the dry seasons and extremely wetted in August. Recorded flooding days within the year of study matched with heavy rainy days including during dry seasons.展开更多
Background: Coronary artery anomalies (CAA) prevalence represents less than 1% of congenital heart diseases. It includes anomalies in origin, course, and termination. Its detection has been easier with advances i...Background: Coronary artery anomalies (CAA) prevalence represents less than 1% of congenital heart diseases. It includes anomalies in origin, course, and termination. Its detection has been easier with advances in imaging techniques using multi-detector computed tomography (MDCT). MDCT helps not only detection of the anomalous origin, but it allows delineation of the course and termination of the arteries, differentiation between benign and malignant courses, and guiding therapeutic interventions. Results: There were consecutive patients with a low-to-intermediate probability of coronary artery disease scanned with 128 MDCT. Each patient underwent a non-contrast prospective gating acquisition for coronary calcium scoring followed by contrast-enhanced helical retrospective gated scans for the detection of coronary artery origin, course, termination, and detection of concomitant atherosclerosis. We scanned 1000 patients with a mean age of 57.5 ± 8.3, and 68% were males. Thirty-two anomalies were noted (3.2%) including;nineteen (1.9%) anomalous origin from the opposite sinus, three (0.3%) anomalous left coronary arteries from the pulmonary artery (ALCAPA), one (0.1%) super dominant left anterior descending artery (LAD) giving origin to the posterior descending artery (PDA), three single coronary arteries (0.3%)in which the left main (LM) and right coronary arteries were originating with a common stem from the right coronary sinus (RCS)and the LM took a pre-pulmonic course. Along with six (0.6%) dual LAD including five (0.5%) patients with type I (short LAD and long diagonal), there was one (0.1%) type 4 with an extra LAD originating from the RCS with a pre-pulmonic course. Conclusions: MDCT allows easy detection of coronary anomalies with high spatial resolution and overcomes limitations in conventional invasive coronary angiography. Based on our study we recommend the use of MDCT as an efficient and feasible modality for the diagnosis of coronary anomalies once this pathology is clinically suspected.展开更多
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
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
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
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
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
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
It is not easy to construct a model to describe the geochemical background in geochemical anomaly detection due to the complexity of the geological setting.Isolation forest and its improved algorithms can detect geoch...It is not easy to construct a model to describe the geochemical background in geochemical anomaly detection due to the complexity of the geological setting.Isolation forest and its improved algorithms can detect geochemical anomalies without modeling the complex geochemical background.These methods can effec-tively extract multivariate anomalies from large volume of high-dimensional geochemical data with unknown population distribution.To test the performance of these algorithms in the detection of mineralization-related geochemical anomalies,the isolation forest,extended isolation forest and generalized isolation forest models were established to detect multivariate anomalies from the stream sediment survey data collected in the Wu-laga area in Heilongjiang Province.The geochemical anomalies detected by the generalized isolation forest model account for 40%of the study area,and contain 100%of the known gold deposits.The geochemical anomalies detected by the isolation forest model account for 20%of the study area,and contain 71%of the known gold deposits.The geochemical anomalies detected by the extended isolation forest algorithm account for 34%of the study area,and contain 100%of the known gold deposits.Therefore,the isolation forest mo-del,extended isolation fo-rest model and generalized isolation forest model are comparable in geochemical anomaly detection.展开更多
基金the National Natural Science Foundation of China(grant numbers 42004051,42274214,41904134).
文摘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.
文摘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.
基金The National Key R&D Program of China under contract Nos 2022YFC3003800,2020YFC1521700 and 2020YFC1521705the National Natural Science Foundation of China under contract No.41830540+3 种基金the Open Fund of the East China Coastal Field Scientific Observation and Research Station of the Ministry of Natural Resources under contract No.OR-SECCZ2022104the Deep Blue Project of Shanghai Jiao Tong University under contract No.SL2020ZD204the Special Funding Project for the Basic Scientific Research Operation Expenses of the Central Government-Level Research Institutes of Public Interest of China under contract No.SZ2102the Zhejiang Provincial Project under contract No.330000210130313013006。
文摘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.
文摘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.
文摘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.
基金National Natural Science Foundation of China (41975073,42274215)Wuxi University Research Start-up Fund for Introduced Talents (2023r037)+1 种基金Qinglan Project of Jiangsu Province for DING Liu-guan。
文摘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.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research[grant number 2020B0301030004]the National Natural Science Foundation of China[grant number 91937302].
基金supported by the National Science Foundation of China (Nos. U1839210, 41874097, 41474072, and 41874108)
文摘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.
文摘Background: Congenital Uterine Anomalies are malformations of the Uterus which occur during embryonic life and result from the abnormal formation, fusion or resorption of the Mullerian ducts. Most of them are asymptomatic and diagnosis is done incidentally or during examinations performed for other purposes. We report three cases of women with pregnancies in malformed uteri. Aim: To depict the diagnostic challenges and therapeutic aspects of management of pregnancies in congenitally malformed Uteri. Case Presentation: The first case was a 22-year-old student who came to consult for a second opinion on the management of an ectopic pregnancy. A 2D Ultrasound done prior revealed an ectopic pregnancy but failed to specify its location in a rudimentary uterine horn. Management with a Multi-dose Methotrexate regimen was initiated but progress was not favorable. She came to us for a second opinion on management. Diagnostic laparoscopy was done and revealed an ectopic pregnancy in a rudimentary uterine horn. This was confirmed by histopathology. Management consisted of resection of the rudimentary horn and a right total salpingectomy. The second case was that of a woman who presented with spotting in early pregnancy. An Obstetric 2D ultrasound done revealed a bicornuate Uterus with a Gestational sac in one horn. She was placed on progesterone supplementation for 2 weeks, with regular antenatal contacts. She had an elective cesarean section at 39 weeks. Surgery revealed a complete Bicornuate Uterus. The post-operative period was uneventful with no complications. The third case was that of a woman with a past history of five successive spontaneous abortions, who presented with spotting at about 8 weeks of gestation. An Obstetric Ultrasound done revealed a Bicornuate Uterus and an embryo in one cornus. She was admitted, given her poor obstetric history, for about 14 days and placed on progesterone supplementation till 20 weeks of gestation. Antenatal contacts were regular and she had an emergency cesarean section at 36 weeks. There were no complications in the post operative period. Conclusion: The high degree of diagnostic accuracy makes 3D ultrasound the diagnostic modality of choice. Nevertheless, 2D and Hysterosalpingography can be used as well. Management of pregnancies in women with congenital Uterine anomalies varies per case as presenting symptoms and outcomes with pregnancies are not alike. When diagnosed out of pregnancy, and depending on the type of anomaly, surgical management may be recommended.
基金This research was financed by grants from the Innovation Cultivation Fund of the Seventh Medical Center of People's Liberation Army General Hospital(QZX-2023-17)the Youth Innovation Fund of People's Liberation Army General Hospital(22QNFC095).
文摘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.
基金financially supported by Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences(Grant No.E221110015)。
文摘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.
文摘Extreme weather anomalies such as rainfall and its subsequent flood events are governed by complex weather systems and interactions between them. It is important to understand the drivers of such events as it helps prepare for and mitigate or respond to the related impacts. In line with the above statements, quarter-hourly data for the year 2021 recorded in the Yaounde meteorological station were synthesized to come out with daily and dekadal (10-day averaged) anomalies of six climate factors (rainfall, temperature, insolation, relative humidity, dew point and wind speed), in order to assess the occurrences and severity of floods to changing weather patterns in Yaounde. In addition, Precipitation Concentration Index (PCI) was computed to evaluate the distribution and analyse the frequency and intensity of precipitation. Coefficient of variation (CV) was used to estimate the seasonal and annual variation of rainfall patterns, while Mann-Kendall (MK) trend test was performed to detect weather anomalies (12-month period variation) in quarter-hourly rainfall data from January 1<sup>st</sup> to December 31<sup>st</sup> 2021. The Standard Precipitation Index (SPI) was also used to quantify the rainfall deficiency of the observed time scale. Results reveal that based on the historical data from 1979 to 2018 in the bimodal rainfall forest zone, maximum and minimum temperature averages recorded in Yaounde in 2021 were mostly above historical average values. Precipitations were rare during dry seasons, with range value of 0 - 13.6 mm for the great dry season and 0 - 21.4 mm for the small dry season. Whereas during small and great rainy seasons, rainfalls were regular with intensity varying between 0 and 50 mm, and between 0 and 90.4 mm, respectively. The MK trend test showed that there was a statistical significant increase in rainfall trend for the month of August at a 5% level of significance, while a significant decreasing trend was observed in July and December. There was a strong irregular rainfall distribution during the months of February, July and December 2021, with a weather being mildly wetted during all the dry seasons and extremely wetted in August. Recorded flooding days within the year of study matched with heavy rainy days including during dry seasons.
文摘Background: Coronary artery anomalies (CAA) prevalence represents less than 1% of congenital heart diseases. It includes anomalies in origin, course, and termination. Its detection has been easier with advances in imaging techniques using multi-detector computed tomography (MDCT). MDCT helps not only detection of the anomalous origin, but it allows delineation of the course and termination of the arteries, differentiation between benign and malignant courses, and guiding therapeutic interventions. Results: There were consecutive patients with a low-to-intermediate probability of coronary artery disease scanned with 128 MDCT. Each patient underwent a non-contrast prospective gating acquisition for coronary calcium scoring followed by contrast-enhanced helical retrospective gated scans for the detection of coronary artery origin, course, termination, and detection of concomitant atherosclerosis. We scanned 1000 patients with a mean age of 57.5 ± 8.3, and 68% were males. Thirty-two anomalies were noted (3.2%) including;nineteen (1.9%) anomalous origin from the opposite sinus, three (0.3%) anomalous left coronary arteries from the pulmonary artery (ALCAPA), one (0.1%) super dominant left anterior descending artery (LAD) giving origin to the posterior descending artery (PDA), three single coronary arteries (0.3%)in which the left main (LM) and right coronary arteries were originating with a common stem from the right coronary sinus (RCS)and the LM took a pre-pulmonic course. Along with six (0.6%) dual LAD including five (0.5%) patients with type I (short LAD and long diagonal), there was one (0.1%) type 4 with an extra LAD originating from the RCS with a pre-pulmonic course. Conclusions: MDCT allows easy detection of coronary anomalies with high spatial resolution and overcomes limitations in conventional invasive coronary angiography. Based on our study we recommend the use of MDCT as an efficient and feasible modality for the diagnosis of coronary anomalies once this pathology is clinically suspected.
基金This study was supported by the Pediatric Heart Center at Skåne University Hospital Lund and Lund University,and by the Swedish Children’s Heart Association.
文摘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.
基金funded by the National Natural Science Foundation of China, grant number 11975307the National Defense Science and Technology Innovation Special Zone Project, grant number 19-H863-01-ZT-003-003-12。
文摘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.
基金The National Natural Science Foundation of China under contract No.42006198the Open Fund of the Key Laboratory of Marine Geology and Environment,Chinese Academy of Sciences under contract No.MGE2020KG02.
文摘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.
基金The National Natural Science Foundation of China under contract Nos 42274006,42174041,41774001the Research Fund of University of Science and Technology under contract No.2014TDJH101.
文摘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.
基金supported by Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2022R196)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘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.
基金reviewed and approved by the Institutional Review Board I&II of Taichung Veterans General Hospital(Approval No.TCVGH-IRB No.CE22408B).
文摘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.
文摘It is not easy to construct a model to describe the geochemical background in geochemical anomaly detection due to the complexity of the geological setting.Isolation forest and its improved algorithms can detect geochemical anomalies without modeling the complex geochemical background.These methods can effec-tively extract multivariate anomalies from large volume of high-dimensional geochemical data with unknown population distribution.To test the performance of these algorithms in the detection of mineralization-related geochemical anomalies,the isolation forest,extended isolation forest and generalized isolation forest models were established to detect multivariate anomalies from the stream sediment survey data collected in the Wu-laga area in Heilongjiang Province.The geochemical anomalies detected by the generalized isolation forest model account for 40%of the study area,and contain 100%of the known gold deposits.The geochemical anomalies detected by the isolation forest model account for 20%of the study area,and contain 71%of the known gold deposits.The geochemical anomalies detected by the extended isolation forest algorithm account for 34%of the study area,and contain 100%of the known gold deposits.Therefore,the isolation forest mo-del,extended isolation fo-rest model and generalized isolation forest model are comparable in geochemical anomaly detection.