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Lung cancer metastasis-induced distal esophageal segmental spasm confirmed by individualized peroral endoscopic myotomy:A case report
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作者 Hong Shi Su-Yu Chen +2 位作者 Zhao-Fei Xie Li-Lin Lin Yan Jiang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3321-3327,共7页
BACKGROUND Peroral endoscopic myotomy(POEM)has been widely performed as a standard treatment for achalasia;however,its efficacy and safety for treating distal esophageal segmental spasms induced by cancer metastasis r... BACKGROUND Peroral endoscopic myotomy(POEM)has been widely performed as a standard treatment for achalasia;however,its efficacy and safety for treating distal esophageal segmental spasms induced by cancer metastasis remain unknown.CASE SUMMARY A 72-year-old male was referred to our hospital and complained of progressive dysphagia for two years.Endoscopy revealed a 2 cm long segment esophageal stenosis with intact mucosa and normal cardia.Computed tomography showed a right upper lung mass,and pathology of the right pleural effusion confirmed the diagnosis of right upper lung adenocarcinoma with multiple rib and mediastinal lymph node metastases and right malignant pleural effusion.Individualized POEM was performed first to alleviate dysphagia,and the final diagnosis was changed to esophageal muscle metastasis arising from lung adenocarcinoma.After treatment,the patient could eat soft solid food and received multiple rounds of pembrolizumab-combination chemotherapy.The patient’s progression-free survival was approximately 16 months.Long stable disease was obtained during the 24-month follow-up.CONCLUSION The incidence of distal esophageal segmental spasms induced by muscular metastasis arising from lung adenocarcinoma is extremely low.Individualized POEM can effectively improve a patient’s nutritional status before subsequent chemotherapy can be combined with immune checkpoint inhibitors. 展开更多
关键词 Peroral endoscopic myotomy Distal esophageal segmental spasm Lung cancer Esophageal metastasis Case report
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Numerical Simulation-Based Analysis of the Impact of Overloading on Segmentally Assembled Bridges
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作者 Donghui Ma Wenqi Wu +4 位作者 Yuan Li Lun Zhao Yingchun Cai Pan Guo Shaolin Yang 《Structural Durability & Health Monitoring》 EI 2024年第5期663-681,共19页
Segmentally assembled bridges are increasinglyfinding engineering applications in recent years due to their unique advantages,especially as urban viaducts.Vehicle loads are one of the most important variable loads acti... Segmentally assembled bridges are increasinglyfinding engineering applications in recent years due to their unique advantages,especially as urban viaducts.Vehicle loads are one of the most important variable loads acting on bridge structures.Accordingly,the influence of overloaded vehicles on existing assembled bridge structures is an urgent concern at present.This paper establishes thefinite element model of the segmentally assembled bridge based on ABAQUS software and analyzes the influence of vehicle overload on an assembled girder bridge struc-ture.First,afinite element model corresponding to the target bridge is established based on ABAQUS software,and the load is controlled to simulate vehicle movement in each area of the traveling zone at different times.Sec-ond,the key cross-sections of segmental girder bridges are monitored in real time based on the force character-istics of continuous girder bridges,and they are compared with the simulation results.Finally,a material damage ontology model is introduced,and the structural damage caused by different overloading rates is compared and analyzed.Results show that thefinite element modeling method is accurate by comparing with on-site measured data,and it is suitable for the numerical simulation of segmental girder bridges;Dynamic sensors installed at 1/4L,1/2L,and 3/4L of the segmental girder main beams could be used to identify the dynamic response of segmental girder bridges;The bottom plate of the segmental girder bridge is mostly damaged at the position where the length of the precast beam section changes and the midspan position.With the increase in load,damage in the direction of the bridge develops faster than that in the direction of the transverse bridge.Thefindings of this study can guide maintenance departments in the management and maintenance of bridges and vehicles. 展开更多
关键词 segmentally assembled bridge dynamic response moving loads OVERLOADING structural damage finite element analysis
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Review of plasma exchange and rituximab for prevention of recurrent focal segmental glomerulosclerosis after a prior graft loss
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作者 Sophie Gharaei Hashim Abbas Durga Anil Kanigicherla 《World Journal of Transplantation》 2024年第4期133-139,共7页
BACKGROUND Focal segmental glomerulosclerosis(FSGS)often recurs after transplantation,leading to graft dysfunction and graft loss.Patients who have lost prior grafts due to recurrence are at particularly high risk of ... BACKGROUND Focal segmental glomerulosclerosis(FSGS)often recurs after transplantation,leading to graft dysfunction and graft loss.Patients who have lost prior grafts due to recurrence are at particularly high risk of re-recurrence in subsequent grafts.Rituximab and plasma exchange have been used pre-emptively to prevent post-transplant recurrence.However,the efficacy of such preventative measures remains unclear.AIM To investigate the outcomes of preventative rituximab and plasma exchange for recurrent FSGS in transplant recipients after prior graft loss.METHODS We conducted a systematic review of 11 studies with 32 patients who had experienced prior graft loss due to post-transplant FSGS recurrence and were treated with either pre-emptive plasma exchange alone,rituximab alone,or a combination of both.RESULTS Overall,47%of the 32 patients experienced recurrence despite prophylactic treatment.Re-recurrence was seen in 25%(1/4)with pre-emptive rituximab alone,and 45%recurrence(9/20)with plasma exchange alone.Re-recurrence was noted in 63%with the use of combined plasma exchange and rituximab.CONCLUSION There is a paucity of available evidence in the literature to draw clear conclusions on the benefits of pre-emptive measures to prevent FSGS re-recurrence.The small sample sizes and variations in protocols call for larger and controlled studies to serve this patient population at high risk of recurrence and graft loss. 展开更多
关键词 Focal segmental glomerulosclerosis Glomerular disease Plasma exchange RITUXIMAB TRANSPLANTATION
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Clinicopathological features and medium-term outcomes of histologic variants of primary focal segmental glomerulosclerosis in adults:A retrospective study
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作者 Nazarul Hassan Jafry Shumaila Manan +1 位作者 Rahma Rashid Muhammed Mubarak 《World Journal of Nephrology》 2024年第1期14-24,共11页
BACKGROUND The Columbia classification identified five histological variants of focal segmental glomerulosclerosis(FSGS).The prognostic significance of these variants remains controversial.AIM To evaluate the relative... BACKGROUND The Columbia classification identified five histological variants of focal segmental glomerulosclerosis(FSGS).The prognostic significance of these variants remains controversial.AIM To evaluate the relative frequency,clinicopathologic characteristics,and medium-term outcomes of FSGS variants at a single center in Pakistan.METHODS This retrospective study was conducted at the Department of Nephrology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan on all consecutive adults(≥16 years)with biopsy-proven primary FSGS from January 1995 to December 2017.Studied subjects were treated with steroids as a first-line therapy.The response rates,doubling of serum creatinine,and kidney failure(KF)with replacement therapy were compared between histological variants using ANOVA or Kruskal Wallis,and Chi-square tests as appropriate.Data were analyzed by SPSS version 22.0.P-value≤0.05 was considered significant.RESULTS A total of 401 patients were diagnosed with primary FSGS during the study period.Among these,352(87.7%)had a designated histological variant.The not otherwise specified(NOS)variant was the commonest,being found in 185(53.9%)patients,followed by the tip variant in 100(29.1%)patients.Collapsing(COL),cellular(CEL),and perihilar(PHI)variants were seen in 58(16.9%),6(1.5%),and 3(0.7%)patients,respectively.CEL and PHI variants were excluded from further analysis due to small patient numbers.The mean follow-up period was 36.5±29.2 months.Regarding response rates of variants,patients with TIP lesions achieved remission more frequently(59.5%)than patients with NOS(41.8%)and COL(24.52%)variants(P<0.001).The hazard ratio of complete response among patients with the COL variant was 0.163[95%confidence interval(CI):0.039-0.67]as compared to patients with NOS.The TIP variant showed a hazard ratio of 2.5(95%CI:1.61-3.89)for complete remission compared to the NOS variant.Overall,progressive KF was observed more frequently in patients with the COL variant,43.4%(P<0.001).Among these,24.53%of patients required kidney replacement therapy(P<0.001).The hazard ratio of doubling of serum creatinine among patients with the COL variant was 14.57(95%CI:1.87-113.49)as compared to patients with the TIP variant.CONCLUSION In conclusion,histological variants of FSGS are predictive of response to treatment with immunosuppressants and progressive KF in adults in our setup. 展开更多
关键词 ADULTS Columbia classification Focal segmental glomerulosclerosis Histological variants Kidney failure Kidney failure with replacement therapy
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Clinical course and outcome of adult patients with primary focal segmental glomerulosclerosis with kidney function loss on presentation
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作者 Nazarul Hassan Jafry Sarfraz Sarwar +1 位作者 Tajammul Waqar Muhammed Mubarak 《World Journal of Nephrology》 2024年第4期125-135,共11页
BACKGROUND Kidney function loss or renal insufficiency indicated by elevated creatinine levels and/or an estimated glomerular filtration rate(eGFR)<60 mL/minute/1.73 m²at presentation in patients with primary ... BACKGROUND Kidney function loss or renal insufficiency indicated by elevated creatinine levels and/or an estimated glomerular filtration rate(eGFR)<60 mL/minute/1.73 m²at presentation in patients with primary focal segmental glomerulosclerosis(FSGS)is commonly seen as a poor prognostic marker for kidney survival.However,a pre>vious study from our center suggested this may be due to hemodynamic factors.AIM To observe the clinical and biochemical parameters,treatment response,kidney survival,and overall outcomes of adult patients with primary FSGS presenting with kidney function insufficiency.METHODS This retrospective observational study was conducted at the Department of Nephrology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan,from January 1995 to December 2017.During this period,401 biopsy-proven primary FSGS patients were identified,of which 98(24.4%)presented with kidney function loss or renal insufficiency defined as eGFR<60 mL/minute/1.73 m²at presentation and were studied in detail.RESULTS Among the 98 patients with renal function loss on presentation,the mean age was 30.9 years±13.6 years with a male-to-female ratio of 2.5:1.The mean serum creatinine level was 2.2 mg/dL±1.3 mg/dL and mean eGFR 37.1 mL/minute/1.73 m2±12.8 mL/minute/1.73 m2.The mean 24-hour urinary protein excretion was 5.9 g/day±4.0 g/day,and the mean serum albumin was 2.1 g/dL±1.0 g/dL(median:1.5 g/dL).The mean systolic blood pressure(BP)was 132.7 mmHg±19.8 mmHg,and the mean diastolic BP was 87.4 mmHg±12.7 mmHg.Steroid treatment was given to 81(82.6%)of 98 patients for an average duration of 19.9 weeks±14.4 weeks,with a mean total steroid dose of 4.4 g±1.5 g.Treatment response showed that 20(24.6%)patients achieved complete remission,9(11.1%)achieved partial remission,and 52(64.1%)did not respond.The baseline eGFR was significantly lower in the non-responsive group(P=0.006).The distribution of FSGS variants was also significantly different among steroid-responsive and non-responsive groups(P=0.012).CONCLUSION Renal function loss in FSGS patients at presentation does not necessarily indicate irreversible kidney function loss and a significant number of patients respond to appropriate treatment of the underlying disease. 展开更多
关键词 Focal segmental glomerulosclerosis Kidney function Serum creatinine Treatment response Steroid therapy
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Analysis of the Effect of High-Dose Segmental Citrate Anticoagulation in High Flux Hemodialysis
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作者 Xubo Fu 《Journal of Clinical and Nursing Research》 2024年第5期95-99,共5页
Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for ... Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for maintenance hemodialysis treatment from January 2021 to January 2023.All patients had a high risk of bleeding and received 4%trisodium citrate anticoagulant treatment,administered at a rate of 200 mL/h before and after the dialyzer.The anticoagulant effects achieved by the patients were observed and analyzed.Results:The total number of patients who received high-dose segmented citrate extracorporeal anticoagulation dialysis treatment was 50,with each patient undergoing 100 treatments.During the treatment,2 patients had to end the treatment early due to transmembrane pressure exceeding 30 mmHg and an increase in venous pressure exceeding 250 mmHg;the treatment times for these patients were 20 minutes and 200 minutes,respectively.The remaining patients successfully completed the 4-hour treatment.Blood pH and calcium ion concentration in the venous pot were monitored.It was observed that before dialysis,after 2 hours of dialysis,and at the end of dialysis,the blood pH of the patients remained within a relatively normal range.Although some patient levels changed after dialysis,they remained within the normal range.No adverse reactions(such as numbness of the limbs or convulsions)were observed during the anticoagulant treatment.Conclusion:Administering 4%trisodium citrate at a rate of 200 mL/h before and after the dialyzer achieves a good anticoagulant effect,maintains the patient’s blood gas levels within the normal range at the end of dialysis,and causes no adverse reactions. 展开更多
关键词 High dose segmented citrate High flux HEMODIALYSIS Anticoagulation effect
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Synergism of calycosin and bone marrow-derived mesenchymal stem cells to combat podocyte apoptosis to alleviate adriamycininduced focal segmental glomerulosclerosis 被引量:1
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作者 Qiong-Dan Hu Rui-Zhi Tan +4 位作者 Yuan-Xia Zou Jian-Chun Li Jun-Ming Fan Fahsai Kantawong Li Wang 《World Journal of Stem Cells》 SCIE 2023年第6期617-631,共15页
BACKGROUND Bone marrow-derived mesenchymal stem cells(MSCs)show podocyte-protective effects in chronic kidney disease.Calycosin(CA),a phytoestrogen,is isolated from Astragalus membranaceus with a kidney-tonifying effe... BACKGROUND Bone marrow-derived mesenchymal stem cells(MSCs)show podocyte-protective effects in chronic kidney disease.Calycosin(CA),a phytoestrogen,is isolated from Astragalus membranaceus with a kidney-tonifying effect.CA preconditioning enhances the protective effect of MSCs against renal fibrosis in mice with unilateral ureteral occlusion.However,the protective effect and underlying mechanism of CA-pretreated MSCs(MSCsCA)on podocytes in adriamycin(ADR)-induced focal segmental glomerulosclerosis(FSGS)mice remain unclear.AIM To investigate whether CA enhances the role of MSCs in protecting against podocyte injury induced by ADR and the possible mechanism involved.METHODS ADR was used to induce FSGS in mice,and MSCs,CA,or MSCsCA were administered to mice.Their protective effect and possible mechanism of action on podocytes were observed by Western blot,immunohistochemistry,immunofluorescence,and real-time polymerase chain reaction.In vitro,ADR was used to stimulate mouse podocytes(MPC5)to induce injury,and the supernatants from MSC-,CA-,or MSCsCA-treated cells were collected to observe their protective effects on podocytes.Subsequently,the apoptosis of podocytes was detected in vivo and in vitro by Western blot,TUNEL assay,and immunofluorescence.Overexpression of Smad3,which is involved in apoptosis,was then induced to evaluate whether the MSCsCA-mediated podocyte protective effect is associated with Smad3 inhibition in MPC5 cells.RESULTS CA-pretreated MSCs enhanced the protective effect of MSCs against podocyte injury and the ability to inhibit podocyte apoptosis in ADR-induced FSGS mice and MPC5 cells.Expression of p-Smad3 was upregulated in mice with ADR-induced FSGS and MPC5 cells,which was reversed by MSCCA treatment more significantly than by MSCs or CA alone.When Smad3 was overexpressed in MPC5 cells,MSCsCA could not fulfill their potential to inhibit podocyte apoptosis.CONCLUSION MSCsCA enhance the protection of MSCs against ADR-induced podocyte apoptosis.The underlying mechanism may be related to MSCsCA-targeted inhibition of p-Smad3 in podocytes. 展开更多
关键词 CALYCOSIN Mesenchymal stem cells Focal segmental glomerulosclerosis APOPTOSIS SMAD3
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Visual Semantic Segmentation Based on Few/Zero-Shot Learning:An Overview 被引量:2
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作者 Wenqi Ren Yang Tang +2 位作者 Qiyu Sun Chaoqiang Zhao Qing-Long Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1106-1126,共21页
Visual semantic segmentation aims at separating a visual sample into diverse blocks with specific semantic attributes and identifying the category for each block,and it plays a crucial role in environmental perception... Visual semantic segmentation aims at separating a visual sample into diverse blocks with specific semantic attributes and identifying the category for each block,and it plays a crucial role in environmental perception.Conventional learning-based visual semantic segmentation approaches count heavily on largescale training data with dense annotations and consistently fail to estimate accurate semantic labels for unseen categories.This obstruction spurs a craze for studying visual semantic segmentation with the assistance of few/zero-shot learning.The emergence and rapid progress of few/zero-shot visual semantic segmentation make it possible to learn unseen categories from a few labeled or even zero-labeled samples,which advances the extension to practical applications.Therefore,this paper focuses on the recently published few/zero-shot visual semantic segmentation methods varying from 2D to 3D space and explores the commonalities and discrepancies of technical settlements under different segmentation circumstances.Specifically,the preliminaries on few/zeroshot visual semantic segmentation,including the problem definitions,typical datasets,and technical remedies,are briefly reviewed and discussed.Moreover,three typical instantiations are involved to uncover the interactions of few/zero-shot learning with visual semantic segmentation,including image semantic segmentation,video object segmentation,and 3D segmentation.Finally,the future challenges of few/zero-shot visual semantic segmentation are discussed. 展开更多
关键词 VISUAL segmentATION SEPARATING
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Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel 被引量:2
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作者 Qian Li Zi-Jie Lin +3 位作者 Liu Yang Yue Wang Yue Li Wei-Hua Cai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1275-1289,共15页
The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the... The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 mm.Numerical simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow features.The results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were analyzed.In calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So heat transfer deterioration should be taken seriously in the design and safe operation of vaporizer PCHE. The study of this work clarified the local heat transfer and flow feature of supercritical methane in microchannel and contributed to the deep understanding of supercritical methane flow of the vaporization process in PCHE. 展开更多
关键词 Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis
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Multilevel Attention Unet Segmentation Algorithmfor Lung Cancer Based on CT Images 被引量:1
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作者 Huan Wang Shi Qiu +1 位作者 Benyue Zhang Lixuan Xiao 《Computers, Materials & Continua》 SCIE EI 2024年第2期1569-1589,共21页
Lung cancer is a malady of the lungs that gravely jeopardizes human health.Therefore,early detection and treatment are paramount for the preservation of human life.Lung computed tomography(CT)image sequences can expli... Lung cancer is a malady of the lungs that gravely jeopardizes human health.Therefore,early detection and treatment are paramount for the preservation of human life.Lung computed tomography(CT)image sequences can explicitly delineate the pathological condition of the lungs.To meet the imperative for accurate diagnosis by physicians,expeditious segmentation of the region harboring lung cancer is of utmost significance.We utilize computer-aided methods to emulate the diagnostic process in which physicians concentrate on lung cancer in a sequential manner,erect an interpretable model,and attain segmentation of lung cancer.The specific advancements can be encapsulated as follows:1)Concentration on the lung parenchyma region:Based on 16-bit CT image capturing and the luminance characteristics of lung cancer,we proffer an intercept histogram algorithm.2)Focus on the specific locus of lung malignancy:Utilizing the spatial interrelation of lung cancer,we propose a memory-based Unet architecture and incorporate skip connections.3)Data Imbalance:In accordance with the prevalent situation of an overabundance of negative samples and a paucity of positive samples,we scrutinize the existing loss function and suggest a mixed loss function.Experimental results with pre-existing publicly available datasets and assembled datasets demonstrate that the segmentation efficacy,measured as Area Overlap Measure(AOM)is superior to 0.81,which markedly ameliorates in comparison with conventional algorithms,thereby facilitating physicians in diagnosis. 展开更多
关键词 Lung cancer computed tomography computer-aided diagnosis Unet segmentATION
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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression 被引量:1
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作者 DONG Wen-bo ZHOU Li +2 位作者 DING Shi-feng WANG Ai-ming CAI Jin-yan 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期313-325,共13页
Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ... Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second. 展开更多
关键词 ice channel ship navigation IDENTIFICATION image segmentation corner point regression
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Hysteretic behavior of post-tensioned precast segmental CFT double-column piers
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作者 Li Xian Zhang Zilin +2 位作者 Zhou Tao Xiao Yu Sun Yushun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期747-762,共16页
Considering the desirable behavior of concrete filled steel tube(CFT)columns and the complicated behavior of segmental double-column piers under cyclic loads,three post-tensioned precast segmental CFT double-column pi... Considering the desirable behavior of concrete filled steel tube(CFT)columns and the complicated behavior of segmental double-column piers under cyclic loads,three post-tensioned precast segmental CFT double-column pier specimens were tested to extend their application in moderate and high seismicity areas.The effects of the number of CFT segments and the steel endplates as energy dissipaters on the seismic behavior of the piers were evaluated.The experimental results show that the segmental piers exhibited stable hysteretic behavior with small residual displacements under cyclic loads.All the tested specimens achieved a drift ratio no less than 13%without significant damage and strength deterioration due to the desirable behavior of CFT columns.Since the deformation of segmental columns was mainly concentrated at the column-footing interfaces,the increase of the segment numbers for each column had no obvious effects on the loading capacity but reduced the initial stiffness of the specimens.The use of steel endplates improved the bearing capacity,stiffness and energy dissipation of segmental piers,but weakened their self-centering capacity.Fiber models were also proposed to simulate the hysteretic behavior of the tested specimens,and the influences of segment numbers and prestress levels on seismic behavior were further studied. 展开更多
关键词 precast segmental piers cyclic loading test seismic behavior concrete filled tube column rockinganalysis
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Cascading multi-segment rupture process of the 2023 Turkish earthquake doublet on a complex fault system revealed by teleseismic P wave back projection method 被引量:1
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作者 Bonan Cao Zengxi Ge 《Earthquake Science》 2024年第2期158-173,共16页
In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back proj... In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back projection analysis.Data in two frequency bands(0.5-2 Hz and 1-3 Hz)are used in the imaging processes.The results show that the rupture of the first event extends about 200 km to the northeast and about 150 km to the southwest,lasting~90 s in total.The southwestern rupture is triggered by the northeastern rupture,demonstrating a sequential bidirectional unilateral rupture pattern.The rupture of the second event extends approximately 80 km in both northeast and west directions,lasting~35 s in total and demonstrates a typical bilateral rupture feature.The cascading ruptures on both sides also reflect the occurrence of selective rupture behaviors on bifurcated faults.In addition,we observe super-shear ruptures on certain fault sections with relatively straight fault structures and sparse aftershocks. 展开更多
关键词 2023 Turkish earthquake doublet back projection method cascading segmented rupture process coseismic triggering super-shear ruptures
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Impact of primary percutaneous coronary intervention on ST-segment elevation myocardial infarction patients:A comprehensive analysis 被引量:1
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作者 Eza Nawzad Saeed Abdulsatar Kamil Faeq 《World Journal of Experimental Medicine》 2024年第1期58-69,共12页
BACKGROUND Myocardial infarction,particularly ST-segment elevation myocardial infarction(STEMI),is a key global mortality cause.Our study investigated predictors of mortality in 96 STEMI patients undergoing primary pe... BACKGROUND Myocardial infarction,particularly ST-segment elevation myocardial infarction(STEMI),is a key global mortality cause.Our study investigated predictors of mortality in 96 STEMI patients undergoing primary percutaneous coronary intervention at Erbil Cardiac Center.Multiple factors were identified influencing in-hospital mortality.Significantly,time from symptom onset to hospital arrival emerged as a decisive factor.Consequently,our study hypothesis is:"Reducing time from symptom onset to hospital arrival significantly improves STEMI prognosis."AIM To determine the key factors influencing mortality rates in STEMI patients.METHODS We studied 96 consecutive STEMI patients undergoing primary percutaneous coronary intervention(PPCI)at the Erbil Cardiac Center.Their clinical histories were compiled,and coronary evaluations were performed via angiography on admission.Data included comorbid conditions,onset of cardiogenic shock,complications during PPCI,and more.Post-discharge,one-month follow-up assessments were completed.Statistical significance was set at P<0.05.RESULTS Our results unearthed several significant findings.The in-hospital and 30-d mortality rates among the 96 STEMI patients were 11.2%and 2.3%respectively.On the investigation of independent predictors of in-hospital mortality,we identified atypical presentation,onset of cardiogenic shock,presence of chronic kidney disease,Thrombolysis In Myocardial Infarction grades 0/1/2,triple vessel disease,ventricular tachycardia/ventricular fibrillation,coronary dissection,and the no-reflow phenomenon.Specifically,the recorded average time from symptom onset to hospital arrival amongst patients who did not survive was significantly longer(6.92±3.86 h)compared to those who survived(3.61±1.67 h),P<0.001.These findings underscore the critical role of timely intervention in improving the survival outcomes of STEMI patients.CONCLUSION Our results affirm that early hospital arrival after symptom onset significantly improves survival rates in STEMI patients,highlighting the critical need for prompt intervention. 展开更多
关键词 Percutaneous coronary intervention Impact analysis segment elevation Erbil
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Short- and long-term results of open vs laparoscopic multisegmental resection and anastomosis for synchronous colorectal cancer located in separate segments
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作者 Ji-Chuan Quan Xin-Jun Zhou +8 位作者 Shi-Wen Mei Jun-Guang Liu Wen-Long Qiu Jin-Zhu Zhang Bo Li Yue-Gang Li Xi-Shan Wang Hu Chang Jian-Qiang Tang 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第9期1969-1977,共9页
BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous c... BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous colorectal cancer(SCRC)located in separate segments.AIM To compare the short-term efficacy and long-term prognosis of OMRA as well as LMRA for SCRC located in separate segments.METHODS Patients with SCRC who underwent surgery between January 2010 and December 2021 at the Cancer Hospital,Chinese Academy of Medical Sciences and the Peking University First Hospital were retrospectively recruited.In accordance with the RESULTS LMRA patients showed markedly less intraoperative blood loss than OMRA patients(100 vs 200 mL,P=0.006).Compared to OMRA patients,LMRA patients exhibited markedly shorter postoperative first exhaust time(2 vs 3 d,P=0.001),postoperative first fluid intake time(3 vs 4 d,P=0.012),and postoperative hospital stay(9 vs 12 d,P=0.002).The incidence of total postoperative complications(Clavien-Dindo grade:≥II)was 2.9%and 17.1%(P=0.025)in the LMRA and OMRA groups,respectively,while the incidence of anastomotic leakage was 2.9%and 7.3%(P=0.558)in the LMRA and OMRA groups,respectively.Furthermore,the LMRA group had a higher mean number of lymph nodes dissected than the OMRA group(45.2 vs 37.3,P=0.020).The 5-year overall survival(OS)and disease-free survival(DFS)rates in OMRA patients were 82.9%and 78.3%,respectively,while these rates in LMRA patients were 78.2%and 72.8%,respectively.Multivariate prognostic analysis revealed that N stage[OS:HR hazard ratio(HR)=10.161,P=0.026;DFS:HR=13.017,P=0.013],but not the surgical method(LMRA/OMRA)(OS:HR=0.834,P=0.749;DFS:HR=0.812,P=0.712),was the independent influencing factor in the OS and DFS of patients with SCRC.CONCLUSION LMRA is safe and feasible for patients with SCRC located in separate segments.Compared to OMRA,the LMRA approach has more advantages related to short-term efficacy. 展开更多
关键词 Synchronous colorectal cancer Separate segments Laparoscopic surgery Multisegmental resection Short-term efficacy Prognosis
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Anesthesia for extracorporeal membrane oxygenation-assisted thoracoscopic lower lobe subsegmental resection in a patient with a single left lung:A case report
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作者 Xiang-Feng Wang Zi-Yan Li +3 位作者 Lei Chen Long-Xiang Chen Fang Xie Hui-Qin Luo 《World Journal of Clinical Cases》 SCIE 2023年第18期4368-4376,共9页
BACKGROUND It is difficult and risky for patients with a single lung to undergo thoracoscopic segmental pneumonectomy,and previous reports of related cases are rare.We introduce anesthesia for Extracorporeal membrane ... BACKGROUND It is difficult and risky for patients with a single lung to undergo thoracoscopic segmental pneumonectomy,and previous reports of related cases are rare.We introduce anesthesia for Extracorporeal membrane oxygenation(ECMO)-assisted thoracoscopic lower lobe subsegmental resection in a patient with a single left lung.CASE SUMMARY The patient underwent comprehensive treatment for synovial sarcoma of the right lung and nodules in the lower lobe of the left lung.Examination showed pulmonary function that had severe restrictive ventilation disorder,forced expiratory volume in 1 second of 0.72 L(27.8%),forced vital capacity of 1.0 L(33%),and maximal voluntary ventilation of 33.9 L(35.5%).Lung computed tomography showed a nodular shadow in the lower lobe of the left lung,and lung metastasis was considered.After multidisciplinary consultation and adequate preoperative preparation,thoracoscopic left lower lung lobe S9bii+S10bii combined subsegmental resection was performed with the assistance of total intravenous anesthesia and ECMO intraoperative pulmonary protective ventilation.The patient received postoperative ICU supportive care.After surgical treatment,the patient was successfully withdrawn from ECMO on postoperative Day 1.The tracheal tube was removed on postoperative Day 4,and she was discharged from the hospital on postoperative Day 15.CONCLUSION The multi-disciplinary treatment provided maximum medical optimization for surgical anesthesia and veno-venous ECMO which provided adequate protection for the patient's perioperative treatment. 展开更多
关键词 Left single lung Subpulmonary segmental resection Extracorporeal membrane oxygenation THORACOSCOPIC ANESTHESIA Case report
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Improved organs at risk segmentation based on modified U‐Net with self‐attention and consistency regularisation
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作者 Maksym Manko Anton Popov +1 位作者 Juan Manuel Gorriz Javier Ramirez 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期850-865,共16页
Cancer is one of the leading causes of death in the world,with radiotherapy as one of the treatment options.Radiotherapy planning starts with delineating the affected area from healthy organs,called organs at risk(OAR... Cancer is one of the leading causes of death in the world,with radiotherapy as one of the treatment options.Radiotherapy planning starts with delineating the affected area from healthy organs,called organs at risk(OAR).A new approach to automatic OAR seg-mentation in the chest cavity in Computed Tomography(CT)images is presented.The proposed approach is based on the modified U‐Net architecture with the ResNet‐34 encoder,which is the baseline adopted in this work.The new two‐branch CS‐SA U‐Net architecture is proposed,which consists of two parallel U‐Net models in which self‐attention blocks with cosine similarity as query‐key similarity function(CS‐SA)blocks are inserted between the encoder and decoder,which enabled the use of con-sistency regularisation.The proposed solution demonstrates state‐of‐the‐art performance for the problem of OAR segmentation in CT images on the publicly available SegTHOR benchmark dataset in terms of a Dice coefficient(oesophagus-0.8714,heart-0.9516,trachea-0.9286,aorta-0.9510)and Hausdorff distance(oesophagus-0.2541,heart-0.1514,trachea-0.1722,aorta-0.1114)and significantly outperforms the baseline.The current approach is demonstrated to be viable for improving the quality of OAR segmentation for radiotherapy planning. 展开更多
关键词 3‐D computer vision deep learning deep neural networks image segmentation medical image processing object segmentation
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Empowering Diagnosis: Cutting-Edge Segmentation and Classification in Lung Cancer Analysis
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作者 Iftikhar Naseer Tehreem Masood +4 位作者 Sheeraz Akram Zulfiqar Ali Awais Ahmad Shafiq Ur Rehman Arfan Jaffar 《Computers, Materials & Continua》 SCIE EI 2024年第6期4963-4977,共15页
Lung cancer is a leading cause of global mortality rates.Early detection of pulmonary tumors can significantly enhance the survival rate of patients.Recently,various Computer-Aided Diagnostic(CAD)methods have been dev... Lung cancer is a leading cause of global mortality rates.Early detection of pulmonary tumors can significantly enhance the survival rate of patients.Recently,various Computer-Aided Diagnostic(CAD)methods have been developed to enhance the detection of pulmonary nodules with high accuracy.Nevertheless,the existing method-ologies cannot obtain a high level of specificity and sensitivity.The present study introduces a novel model for Lung Cancer Segmentation and Classification(LCSC),which incorporates two improved architectures,namely the improved U-Net architecture and the improved AlexNet architecture.The LCSC model comprises two distinct stages.The first stage involves the utilization of an improved U-Net architecture to segment candidate nodules extracted from the lung lobes.Subsequently,an improved AlexNet architecture is employed to classify lung cancer.During the first stage,the proposed model demonstrates a dice accuracy of 0.855,a precision of 0.933,and a recall of 0.789 for the segmentation of candidate nodules.The suggested improved AlexNet architecture attains 97.06%accuracy,a true positive rate of 96.36%,a true negative rate of 97.77%,a positive predictive value of 97.74%,and a negative predictive value of 96.41%for classifying pulmonary cancer as either benign or malignant.The proposed LCSC model is tested and evaluated employing the publically available dataset furnished by the Lung Image Database Consortium and Image Database Resource Initiative(LIDC-IDRI).This proposed technique exhibits remarkable performance compared to the existing methods by using various evaluation parameters. 展开更多
关键词 Lung cancer segmentATION AlexNet U-Net classification
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CrossFormer Embedding DeepLabv3+ for Remote Sensing Images Semantic Segmentation
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作者 Qixiang Tong Zhipeng Zhu +2 位作者 Min Zhang Kerui Cao Haihua Xing 《Computers, Materials & Continua》 SCIE EI 2024年第4期1353-1375,共23页
High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the d... High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the difficultyof segmentation. In this paper, an improved network with a cross-region self-attention mechanism for multi-scalefeatures based onDeepLabv3+is designed to address the difficulties of small object segmentation and blurred targetedge segmentation. First,we use CrossFormer as the backbone feature extraction network to achieve the interactionbetween large- and small-scale features, and establish self-attention associations between features at both large andsmall scales to capture global contextual feature information. Next, an improved atrous spatial pyramid poolingmodule is introduced to establish multi-scale feature maps with large- and small-scale feature associations, andattention vectors are added in the channel direction to enable adaptive adjustment of multi-scale channel features.The proposed networkmodel is validated using the PotsdamandVaihingen datasets. The experimental results showthat, compared with existing techniques, the network model designed in this paper can extract and fuse multiscaleinformation, more clearly extract edge information and small-scale information, and segment boundariesmore smoothly. Experimental results on public datasets demonstrate the superiority of ourmethod compared withseveral state-of-the-art networks. 展开更多
关键词 Semantic segmentation remote sensing multiscale self-attention
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Part-Whole Relational Few-Shot 3D Point Cloud Semantic Segmentation
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作者 Shoukun Xu Lujun Zhang +2 位作者 Guangqi Jiang Yining Hua Yi Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3021-3039,共19页
This paper focuses on the task of few-shot 3D point cloud semantic segmentation.Despite some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation an... This paper focuses on the task of few-shot 3D point cloud semantic segmentation.Despite some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation and inaccurate semantic discrimination.To tackle these issues,we first leverage part-whole relationships into the task of 3D point cloud semantic segmentation to capture semantic integrity,which is empowered by the dynamic capsule routing with the module of 3D Capsule Networks(CapsNets)in the embedding network.Concretely,the dynamic routing amalgamates geometric information of the 3D point cloud data to construct higher-level feature representations,which capture the relationships between object parts and their wholes.Secondly,we designed a multi-prototype enhancement module to enhance the prototype discriminability.Specifically,the single-prototype enhancement mechanism is expanded to the multi-prototype enhancement version for capturing rich semantics.Besides,the shot-correlation within the category is calculated via the interaction of different samples to enhance the intra-category similarity.Ablation studies prove that the involved part-whole relations and proposed multi-prototype enhancement module help to achieve complete object segmentation and improve semantic discrimination.Moreover,under the integration of these two modules,quantitative and qualitative experiments on two public benchmarks,including S3DIS and ScanNet,indicate the superior performance of the proposed framework on the task of 3D point cloud semantic segmentation,compared to some state-of-the-art methods. 展开更多
关键词 Few-shot point cloud semantic segmentation CapsNets
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