Compared with traditional nickel-titanium alloy patent foramen ovale occluders,which are widely used in clinical practice,biodegradable patent foramen ovale occluders have obvious differences in material characteristi...Compared with traditional nickel-titanium alloy patent foramen ovale occluders,which are widely used in clinical practice,biodegradable patent foramen ovale occluders have obvious differences in material characteristics,interventional operation mode and postoperative management strategy.This article gives expert consensus on the selection of clinical indications and standardized operating procedures,so as to standardize the clinical application of biodegradable patent foramen ovale occluders.展开更多
Objective:This study was designed to determine the long-term safety and efficacy of using the Amplatzer Duct Occluder II(ADO II)for the closure of various ventricular septal defects(VSDs).Methods:From January 2011 to ...Objective:This study was designed to determine the long-term safety and efficacy of using the Amplatzer Duct Occluder II(ADO II)for the closure of various ventricular septal defects(VSDs).Methods:From January 2011 to December 2019,selected VSD patients were treated through transcatheter intervention using ADO II occluders.The closure results and complications from 188 patients,involving 167 perimembranous ventricular septal defects(pmVSDs),9 intracristal VSDs,11 post surgery residual shunts and 1 post closure residual shunt with the mean outlet diameter3.1±0.8 mm under angiography,were enrolled in this study.Results:The success rate was 98.9%for all procedures.During the median 77-month follow-up period,no cases of complete atrioventricular block(cAVB),infective endocarditis or death occurred.One major adverse event(0.5%)was recorded:cerebrovascular accident occurred 1 day after the procedure in one patient who was transferred to the neurology department.The residual shunt rate was 44.6%,which was the most common minor adverse event.The cardiac conduction block rate was 4.3%.Specifically,one pmVSD patient developed intermittent LBBB during the 28-month follow-up.There were 3 patients(1.6%)with new-onset mild tricuspid insufficiency,and the insufficiency degree was stable during follow-up.There was no new-onset aortic insufficiency that occurred.Conclusions:Transcatheter closure of pmVSDs,some intracristal VSDs,some postsurgery or postclosure residual shunts using ADO II occluders were both safe and effective and yielded excellent long-term results in selected patients.展开更多
Major aortopulmonary collateral arteries (MAPCAs) are congenital vessels that arise from the aorta or its first-order branches and are distally connected to the pulmonary arterial vasculature, thereby providing pulmon...Major aortopulmonary collateral arteries (MAPCAs) are congenital vessels that arise from the aorta or its first-order branches and are distally connected to the pulmonary arterial vasculature, thereby providing pulmonary blood flow. MAPCAs are often associated with cyanotic congenital heart disease with decreased pulmonary blood flow. Isolated MAPCAs are rare in patients without congenital heart disease with structurally normal hearts. Sometimes, isolated congenital MAPCAs can occur without any lung disease. Isolated MAPCAs represent the occurrence of collaterals in the absence of underlying heart disease, which commonly presents as heart failure, recurrent respiratory tract infection, and pulmonary artery hypertension. We report a rare case of congestive heart failure in a 6-year-old patient with dual arterial supply to an otherwise normal right lung, with a normal bronchial tree, and a structurally normal heart. The patient was successfully managed by the closure of collaterals by Amplatzer vascular plugs II (AVPII) and Amplatzer Piccolo Occluders.展开更多
The transcatheter closure of perimembranous ventricular septal defect （pmVSD） has become a promising treatment modality. However, transcatheter closure of multiple pmVSDs with giant aneurysm is still very challengin...The transcatheter closure of perimembranous ventricular septal defect （pmVSD） has become a promising treatment modality. However, transcatheter closure of multiple pmVSDs with giant aneurysm is still very challenging. We present our preliminary experiences.展开更多
Since Parodi et all reported the first successful case of endovascular treatment for abdominal aortic aneurysm （AAA） in 1991, the endovascular repair has become an important option for the surgical treatment of aort...Since Parodi et all reported the first successful case of endovascular treatment for abdominal aortic aneurysm （AAA） in 1991, the endovascular repair has become an important option for the surgical treatment of aortic aneurysms.2-4 The occluder is a newly-developed device introduced intraluminally to block the blood flow in certain arteries. It was mainly adopted by cardiologists in occluding the ventricular septal defect （VSD） and atrial septal defect （ASD）.5-6 Afterwards, vascular surgeons found it could also be used in endovascular repair of aortic aneurysms, especially when the aorto-uni-iliac （AUI） stent-grafts were implanted.7 Herein we present 6 patients with AAA, who were treated with endovascular deployment of AUI stent-grafts combined with a newly- designed occluder.展开更多
Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveill...Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveillance,biometric authentication,and human-computer interaction.This paper provides a comprehensive review of face detection techniques developed to handle occluded faces.Studies are categorized into four main approaches:feature-based,machine learning-based,deep learning-based,and hybrid methods.We analyzed state-of-the-art studies within each category,examining their methodologies,strengths,and limitations based on widely used benchmark datasets,highlighting their adaptability to partial and severe occlusions.The review also identifies key challenges,including dataset diversity,model generalization,and computational efficiency.Our findings reveal that deep learning methods dominate recent studies,benefiting from their ability to extract hierarchical features and handle complex occlusion patterns.More recently,researchers have increasingly explored Transformer-based architectures,such as Vision Transformer(ViT)and Swin Transformer,to further improve detection robustness under challenging occlusion scenarios.In addition,hybrid approaches,which aim to combine traditional andmodern techniques,are emerging as a promising direction for improving robustness.This review provides valuable insights for researchers aiming to develop more robust face detection systems and for practitioners seeking to deploy reliable solutions in real-world,occlusionprone environments.Further improvements and the proposal of broader datasets are required to developmore scalable,robust,and efficient models that can handle complex occlusions in real-world scenarios.展开更多
Face detection is a critical component inmodern security,surveillance,and human-computer interaction systems,with widespread applications in smartphones,biometric access control,and public monitoring.However,detecting...Face detection is a critical component inmodern security,surveillance,and human-computer interaction systems,with widespread applications in smartphones,biometric access control,and public monitoring.However,detecting faces with high levels of occlusion,such as those covered by masks,veils,or scarves,remains a significant challenge,as traditional models often fail to generalize under such conditions.This paper presents a hybrid approach that combines traditional handcrafted feature extraction technique called Histogram of Oriented Gradients(HOG)and Canny edge detection with modern deep learning models.The goal is to improve face detection accuracy under occlusions.The proposed method leverages the structural strengths of HOG and edge-based object proposals while exploiting the feature extraction capabilities of Convolutional Neural Networks(CNNs).The effectiveness of the proposed model is assessed using a custom dataset containing 10,000 heavily occluded face images and a subset of the Common Objects in Context(COCO)dataset for non-face samples.The COCO dataset was selected for its variety and realism in background contexts.Experimental evaluations demonstrate significant performance improvements compared to baseline CNN models.Results indicate that DenseNet121 combined with HOG outperforms other counterparts in classification metrics with an F1-score of 87.96%and precision of 88.02%.Enhanced performance is achieved through reduced false positives and improved localization accuracy with the integration of object proposals based on Canny and contour detection.While the proposed method increases inference time from 33.52 to 97.80 ms,it achieves a notable improvement in precision from 80.85% to 88.02% when comparing the baseline DenseNet121 model to its hybrid counterpart.Limitations of the method include higher computational cost and the need for careful tuning of parameters across the edge detection,handcrafted features,and CNN components.These findings highlight the potential of combining handcrafted and learned features for occluded face detection tasks.展开更多
The lack of facial features caused by wearing masks degrades the performance of facial recognition systems.Traditional occluded face recognition methods cannot integrate the computational resources of the edge layer a...The lack of facial features caused by wearing masks degrades the performance of facial recognition systems.Traditional occluded face recognition methods cannot integrate the computational resources of the edge layer and the device layer.Besides,previous research fails to consider the facial characteristics including occluded and unoccluded parts.To solve the above problems,we put forward a device-edge collaborative occluded face recognition method based on cross-domain feature fusion.Specifically,the device-edge collaborative face recognition architecture gets the utmost out of maximizes device and edge resources for real-time occluded face recognition.Then,a cross-domain facial feature fusion method is presented which combines both the explicit domain and the implicit domain facial.Furthermore,a delay-optimized edge recognition task scheduling method is developed that comprehensively considers the task load,computational power,bandwidth,and delay tolerance constraints of the edge.This method can dynamically schedule face recognition tasks and minimize recognition delay while ensuring recognition accuracy.The experimental results show that the proposed method achieves an average gain of about 21%in recognition latency,while the accuracy of the face recognition task is basically the same compared to the baseline method.展开更多
Dissimilar metal joining between NiTi shape memory alloy（SMA） and stainless steel was conducted.A cluster of NiTi SMA wires were first joined with tungsten inert gas（TIG） welding process,then the NiTi SMA TIG weld...Dissimilar metal joining between NiTi shape memory alloy（SMA） and stainless steel was conducted.A cluster of NiTi SMA wires were first joined with tungsten inert gas（TIG） welding process,then the NiTi SMA TIG weld was welded to a stainless steel pipe with laser spot welding process.The microstructure of the welds was examined with an optical microscope and the elemental distribution in the welds was measured by electron probe microanalysis（EPMA）.The results show that TiC compounds dispersively distribute in the NiTi SMA TIG weld.However,the amount of TiC compounds greatly decreases around the fusion boundary of the laser spot weld between the NiTi SMA and stainless steel.Mutual diffusion between NiTi shape memory alloy and stainless steel happen within a short distance near the fusion boundary,and intermetallic compounds such as Ni3Ti＋（Fe,Ni）Ti appear around the fusion boundary.展开更多
The enrichment of chloride anion within the occluded cell （OC） for Type 304 austenitic stainless steel in low chloride concentration solution has been investigated by means of a simulated OC. The influence of the en...The enrichment of chloride anion within the occluded cell （OC） for Type 304 austenitic stainless steel in low chloride concentration solution has been investigated by means of a simulated OC. The influence of the enrichment of chloride anion on stress corrosion crack （SCC） of Type 304 stainless steel has been studied. It was observed that the amount of chloride anion migration was proportional to the charge flowing through the anode. Owning to the effects of enrichment of chloride anion, low chloride concentration solution could induce SCC for Type 304 stainless steel.展开更多
In patients with a malignant biliary obstruction who require biliary drainage,a self-expandable metallic stent(SEMS) provides longer patency duration than a plastic stent(PS).Nevertheless,a stent occlusion by tumor in...In patients with a malignant biliary obstruction who require biliary drainage,a self-expandable metallic stent(SEMS) provides longer patency duration than a plastic stent(PS).Nevertheless,a stent occlusion by tumor ingrowth,tumor overgrowth and biliary sludge may develop.There are several methods to manage occluded SEMS.Endoscopic management is the preferred treatment,whereas percutaneous intervention is an alternative approach.Endoscopic treatment involves mechanical cleaning with a balloon and a second stent insertion as stent-in-stent with either PS or SEMS.Technical feasibility,patient survival and cost-effectiveness are important factors that determine the method of re-drainage and stent selection.展开更多
In order to improve the success rate of chronic total occlusion (CTO)percutaneous coronary intervention (PCI), retrograde approach has been attracted more attention.Recent study reported the collateral perforation rat...In order to improve the success rate of chronic total occlusion (CTO)percutaneous coronary intervention (PCI), retrograde approach has been attracted more attention.Recent study reported the collateral perforation rate was 6.9% in retrograde CTO PCI.[1,2] Collateral related perforations were higher in patients with the epicardial collateral than that with the septal collateral.[3]Several techniques have been developed to deal with the collateral branch perforation.Here,we described the treatment of epicardial collateral branch perforation by absorbable suture segments embolization through microcatheter during retrograde CTO PCI.展开更多
Non-valvular atrial fibrillation is associated with a significantly increased risk of embolic stroke due to blood clot forming predominantly in the left atrial appendage(LAA). Preventive measures to avoid embolic even...Non-valvular atrial fibrillation is associated with a significantly increased risk of embolic stroke due to blood clot forming predominantly in the left atrial appendage(LAA). Preventive measures to avoid embolic events are permanent administration of anticoagulants or surgical closure of the LAA. Various clinical trials provide evidence about safety, effectiveness and therapeutic success of LAA occlusion using various cardiac occluder devices. The use of such implants for interventional closure of the LAA is likely to become a valuable alternative for stroke prevention, especially in patients with contraindication for oral anticoagulation as safety, clinical benefit and cost-effectiveness of LAA occlusion has recently been demonstrated.展开更多
A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patie...A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly （155 m）. Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46%and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk dis-tance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient’s heart functions.展开更多
Video surveillance is an active research topic in computer vision.In this paper,humans and cars identifcation technique suitable for real time video surveillance systems is presented.The technique we proposed includes...Video surveillance is an active research topic in computer vision.In this paper,humans and cars identifcation technique suitable for real time video surveillance systems is presented.The technique we proposed includes background subtraction,foreground segmentation,shadow removal,feature extraction and classifcation.The feature extraction of the extracted foreground objects is done via a new set of afne moment invariants based on statistics method and these were used to identify human or car.When the partial occlusion occurs,although features of full body cannot be extracted,our proposed technique extracts the features of head shoulder.Our proposed technique can identify human by extracting the human head-shoulder up to 60%–70%occlusion.Thus,it has a better classifcation to solve the issue of the loss of property arising from human occluded easily in practical applications.The whole system works at approximately 16 29 fps and thus it is suitable for real-time applications.The accuracy for our proposed technique in identifying human is very good,which is 98.33%,while for cars identifcation,the accuracy is also good,which is 94.41%.The overall accuracy for our proposed technique in identifying human and car is at 98.04%.The experiment results show that this method is efective and has strong robustness.展开更多
In order to provide scientific basis for advanced applications of near eutectic Al-Si-Mg alloys as architectural profiles, a comparative study on the corrosion resistance of an as-extruded near eutectic AI-Si-Mg alloy...In order to provide scientific basis for advanced applications of near eutectic Al-Si-Mg alloys as architectural profiles, a comparative study on the corrosion resistance of an as-extruded near eutectic AI-Si-Mg alloy and AA6063 aluminium alloy was carried out by means of neutral salt spray test. The corroded surfaces of the alloys were examined with optical microscopy and scanning electron microscope （SEM）. Results show that the corrosion type of these two alloys is pitting corrosion. The number of corrosion pits in the AA6063 aluminium alloy is more than that in the near eutectic AI-Si-Mg alloy, but the pits in the latter alloy are much larger and deeper. Because the relatively low polarization resistance of the near eutectic alloy leads to poorer repassivation ability, autocatalytic acidification occurs once a pit forms. Thus, occluded corrosion cells are developed in this alloy.展开更多
BACKGROUND The off-label use of various devices has been reported for the transcatheter closure of perimembranous ventricular septal defects(PmVSD) because of serious complications, such as heart block and tricuspid r...BACKGROUND The off-label use of various devices has been reported for the transcatheter closure of perimembranous ventricular septal defects(PmVSD) because of serious complications, such as heart block and tricuspid regurgitation(TR),associated with conventional ventricular septal defect devices. However, whether certain defects such as PmVSD with abnormally attached tricuspid are fit for interventional treatment is still disputable.AIM To explore the feasibility and safety of transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae using an improved patent ductus arteriosus(PDA) occluder.METHODS We retrospectively analyzed 20 patients diagnosed with PmVSD with abnormally attached tricuspid chordae tendineae who underwent interventional treatment using an improved PDA occluder at our center from January 2012 to January 2016. Baseline characteristics and procedural and follow-up data were analyzed.RESULTS All 20 patients achieved procedure success. No heart block occurred during the operation. One patient had a transient complete right bundle branch block within48 h post-procedure and reverted to normal rhythm after intravenous injections of dexamethasone for 3 d. For all 20 patients, no residual shunt was observed by transthoracic echocardiography post-procedure. During the average follow-up period of 2.4 years, no severe TR was observed.CONCLUSION Using of the improved PDA occluder for the transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae is a safe and promising treatment option. However, long-term follow-up in a large group of patients is still warranted.展开更多
The difficulty of multiple targets tracking is how to quickly fulfill the target matching from one flame image to another and fix the position of the target. In order to accurately choose target feature information fo...The difficulty of multiple targets tracking is how to quickly fulfill the target matching from one flame image to another and fix the position of the target. In order to accurately choose target feature information for reliable matching, simplify operations under the reliable precondition, and realize precise moving objects tracking, an approach based on Kalman prediction and feature matching was proposed. The position of the target in next frame image was predicted by Kalman, and then the moving objects of two adjacent frames were matched by the centroid and area methods. When occlusion occurs, the best matching result was found to realize tracking by matching matrix algorithm. The simulation results show that the proposed method can achieve multiple targets tracking accurately and in real-time under complicated motion movements.展开更多
AIM To investigate the interaction of Zot withmicrotubule.METHODS Zot affinity column was applied topurify Zot-binding protein（s）from crudeintestinal cell lysates.After incubation at roomtemperature,the column was w...AIM To investigate the interaction of Zot withmicrotubule.METHODS Zot affinity column was applied topurify Zot-binding protein（s）from crudeintestinal cell lysates.After incubation at roomtemperature,the column was washed and theproteins bound to the Zot affinity column wereeluted by step gradient with NaCl(0.3 mol·L<sup>-1</sup>-0.5mol·L<sup>-1</sup>).The fractions were subjected to6.0%-15.0%（w/v）gradient SDS-PAGE andthen transferred to PVDF membrane for N-terminal sequencing.Purified Zot and tauprotein were blotted by using anti-Zot or anti-tauantibodies.Finally,purified Zot was tested in anin vitro tubulin binding assay.RESULTS Fractions from Zot affinity columnyielded two protein bands with a Mr of 60 kU and45kU respectively.The N-terminal sequence ofthe 60 kU band resulted identical to β-tubulin.Zot also cross-reacts with anti-tau antibodies.Inthe in vitro tubulin binding assay,Zot co-precipitate with Mt,further suggesting that Zotpossesses tubulin-binding properties.CONCLUSION Taken together,these resultssuggest that Zot regulates the permeability ofintestinal tight junctions by binding tointracellular Mt,with the subsequent activationof the intracellular signaling leading to thepermeabilization of intercellular tight junctions.展开更多
基金Chinese Academy of Medical Sciences Fuwai Hospital High Level Hospital clinical research fund(2022-GSPGG-18).
文摘Compared with traditional nickel-titanium alloy patent foramen ovale occluders,which are widely used in clinical practice,biodegradable patent foramen ovale occluders have obvious differences in material characteristics,interventional operation mode and postoperative management strategy.This article gives expert consensus on the selection of clinical indications and standardized operating procedures,so as to standardize the clinical application of biodegradable patent foramen ovale occluders.
基金This study was supported by grant from Doctoral Start-Up Foundation of Liaoning Province of China(2019-BS-266).
文摘Objective:This study was designed to determine the long-term safety and efficacy of using the Amplatzer Duct Occluder II(ADO II)for the closure of various ventricular septal defects(VSDs).Methods:From January 2011 to December 2019,selected VSD patients were treated through transcatheter intervention using ADO II occluders.The closure results and complications from 188 patients,involving 167 perimembranous ventricular septal defects(pmVSDs),9 intracristal VSDs,11 post surgery residual shunts and 1 post closure residual shunt with the mean outlet diameter3.1±0.8 mm under angiography,were enrolled in this study.Results:The success rate was 98.9%for all procedures.During the median 77-month follow-up period,no cases of complete atrioventricular block(cAVB),infective endocarditis or death occurred.One major adverse event(0.5%)was recorded:cerebrovascular accident occurred 1 day after the procedure in one patient who was transferred to the neurology department.The residual shunt rate was 44.6%,which was the most common minor adverse event.The cardiac conduction block rate was 4.3%.Specifically,one pmVSD patient developed intermittent LBBB during the 28-month follow-up.There were 3 patients(1.6%)with new-onset mild tricuspid insufficiency,and the insufficiency degree was stable during follow-up.There was no new-onset aortic insufficiency that occurred.Conclusions:Transcatheter closure of pmVSDs,some intracristal VSDs,some postsurgery or postclosure residual shunts using ADO II occluders were both safe and effective and yielded excellent long-term results in selected patients.
文摘Major aortopulmonary collateral arteries (MAPCAs) are congenital vessels that arise from the aorta or its first-order branches and are distally connected to the pulmonary arterial vasculature, thereby providing pulmonary blood flow. MAPCAs are often associated with cyanotic congenital heart disease with decreased pulmonary blood flow. Isolated MAPCAs are rare in patients without congenital heart disease with structurally normal hearts. Sometimes, isolated congenital MAPCAs can occur without any lung disease. Isolated MAPCAs represent the occurrence of collaterals in the absence of underlying heart disease, which commonly presents as heart failure, recurrent respiratory tract infection, and pulmonary artery hypertension. We report a rare case of congestive heart failure in a 6-year-old patient with dual arterial supply to an otherwise normal right lung, with a normal bronchial tree, and a structurally normal heart. The patient was successfully managed by the closure of collaterals by Amplatzer vascular plugs II (AVPII) and Amplatzer Piccolo Occluders.
基金This work was Supported by the grant from the Natural Science Foundation of Shandong Province （No. ZR2012HM073）.
文摘The transcatheter closure of perimembranous ventricular septal defect （pmVSD） has become a promising treatment modality. However, transcatheter closure of multiple pmVSDs with giant aneurysm is still very challenging. We present our preliminary experiences.
文摘Since Parodi et all reported the first successful case of endovascular treatment for abdominal aortic aneurysm （AAA） in 1991, the endovascular repair has become an important option for the surgical treatment of aortic aneurysms.2-4 The occluder is a newly-developed device introduced intraluminally to block the blood flow in certain arteries. It was mainly adopted by cardiologists in occluding the ventricular septal defect （VSD） and atrial septal defect （ASD）.5-6 Afterwards, vascular surgeons found it could also be used in endovascular repair of aortic aneurysms, especially when the aorto-uni-iliac （AUI） stent-grafts were implanted.7 Herein we present 6 patients with AAA, who were treated with endovascular deployment of AUI stent-grafts combined with a newly- designed occluder.
基金funded by A’Sharqiyah University,Sultanate of Oman,under Research Project grant number(BFP/RGP/ICT/22/490).
文摘Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveillance,biometric authentication,and human-computer interaction.This paper provides a comprehensive review of face detection techniques developed to handle occluded faces.Studies are categorized into four main approaches:feature-based,machine learning-based,deep learning-based,and hybrid methods.We analyzed state-of-the-art studies within each category,examining their methodologies,strengths,and limitations based on widely used benchmark datasets,highlighting their adaptability to partial and severe occlusions.The review also identifies key challenges,including dataset diversity,model generalization,and computational efficiency.Our findings reveal that deep learning methods dominate recent studies,benefiting from their ability to extract hierarchical features and handle complex occlusion patterns.More recently,researchers have increasingly explored Transformer-based architectures,such as Vision Transformer(ViT)and Swin Transformer,to further improve detection robustness under challenging occlusion scenarios.In addition,hybrid approaches,which aim to combine traditional andmodern techniques,are emerging as a promising direction for improving robustness.This review provides valuable insights for researchers aiming to develop more robust face detection systems and for practitioners seeking to deploy reliable solutions in real-world,occlusionprone environments.Further improvements and the proposal of broader datasets are required to developmore scalable,robust,and efficient models that can handle complex occlusions in real-world scenarios.
基金funded by A’Sharqiyah University,Sultanate of Oman,under Research Project Grant Number(BFP/RGP/ICT/22/490).
文摘Face detection is a critical component inmodern security,surveillance,and human-computer interaction systems,with widespread applications in smartphones,biometric access control,and public monitoring.However,detecting faces with high levels of occlusion,such as those covered by masks,veils,or scarves,remains a significant challenge,as traditional models often fail to generalize under such conditions.This paper presents a hybrid approach that combines traditional handcrafted feature extraction technique called Histogram of Oriented Gradients(HOG)and Canny edge detection with modern deep learning models.The goal is to improve face detection accuracy under occlusions.The proposed method leverages the structural strengths of HOG and edge-based object proposals while exploiting the feature extraction capabilities of Convolutional Neural Networks(CNNs).The effectiveness of the proposed model is assessed using a custom dataset containing 10,000 heavily occluded face images and a subset of the Common Objects in Context(COCO)dataset for non-face samples.The COCO dataset was selected for its variety and realism in background contexts.Experimental evaluations demonstrate significant performance improvements compared to baseline CNN models.Results indicate that DenseNet121 combined with HOG outperforms other counterparts in classification metrics with an F1-score of 87.96%and precision of 88.02%.Enhanced performance is achieved through reduced false positives and improved localization accuracy with the integration of object proposals based on Canny and contour detection.While the proposed method increases inference time from 33.52 to 97.80 ms,it achieves a notable improvement in precision from 80.85% to 88.02% when comparing the baseline DenseNet121 model to its hybrid counterpart.Limitations of the method include higher computational cost and the need for careful tuning of parameters across the edge detection,handcrafted features,and CNN components.These findings highlight the potential of combining handcrafted and learned features for occluded face detection tasks.
基金supported by National Natural Science Foundation of China(61901071,61871062,61771082,U20A20157)Science and Natural Science Foundation of Chongqing,China(cstc2020jcyjzdxmX0024)+6 种基金University Innovation Research Group of Chongqing(CXQT20017)Program for Innovation Team Building at Institutions of Higher Education in Chongqing(CXTDX201601020)Natural Science Foundation of Chongqing,China(CSTB2022NSCQ-MSX0600)Youth Innovation Group Support Program of ICE Discipline of CQUPT(SCIE-QN-2022-04)Chongqing Municipal Technology Innovation and Application Development Special Key Project(cstc2020jscxdxwtBX0053)China Postdoctoral Science Foundation Project,China(2022MD723723)Chongqing Postdoctoral Research Project Special Funding,China(2023CQBSHTB3092)。
文摘The lack of facial features caused by wearing masks degrades the performance of facial recognition systems.Traditional occluded face recognition methods cannot integrate the computational resources of the edge layer and the device layer.Besides,previous research fails to consider the facial characteristics including occluded and unoccluded parts.To solve the above problems,we put forward a device-edge collaborative occluded face recognition method based on cross-domain feature fusion.Specifically,the device-edge collaborative face recognition architecture gets the utmost out of maximizes device and edge resources for real-time occluded face recognition.Then,a cross-domain facial feature fusion method is presented which combines both the explicit domain and the implicit domain facial.Furthermore,a delay-optimized edge recognition task scheduling method is developed that comprehensively considers the task load,computational power,bandwidth,and delay tolerance constraints of the edge.This method can dynamically schedule face recognition tasks and minimize recognition delay while ensuring recognition accuracy.The experimental results show that the proposed method achieves an average gain of about 21%in recognition latency,while the accuracy of the face recognition task is basically the same compared to the baseline method.
基金Project(50974046/E041607) supported by the National Natural Science Foundation of China
文摘Dissimilar metal joining between NiTi shape memory alloy（SMA） and stainless steel was conducted.A cluster of NiTi SMA wires were first joined with tungsten inert gas（TIG） welding process,then the NiTi SMA TIG weld was welded to a stainless steel pipe with laser spot welding process.The microstructure of the welds was examined with an optical microscope and the elemental distribution in the welds was measured by electron probe microanalysis（EPMA）.The results show that TiC compounds dispersively distribute in the NiTi SMA TIG weld.However,the amount of TiC compounds greatly decreases around the fusion boundary of the laser spot weld between the NiTi SMA and stainless steel.Mutual diffusion between NiTi shape memory alloy and stainless steel happen within a short distance near the fusion boundary,and intermetallic compounds such as Ni3Ti＋（Fe,Ni）Ti appear around the fusion boundary.
文摘The enrichment of chloride anion within the occluded cell （OC） for Type 304 austenitic stainless steel in low chloride concentration solution has been investigated by means of a simulated OC. The influence of the enrichment of chloride anion on stress corrosion crack （SCC） of Type 304 stainless steel has been studied. It was observed that the amount of chloride anion migration was proportional to the charge flowing through the anode. Owning to the effects of enrichment of chloride anion, low chloride concentration solution could induce SCC for Type 304 stainless steel.
文摘In patients with a malignant biliary obstruction who require biliary drainage,a self-expandable metallic stent(SEMS) provides longer patency duration than a plastic stent(PS).Nevertheless,a stent occlusion by tumor ingrowth,tumor overgrowth and biliary sludge may develop.There are several methods to manage occluded SEMS.Endoscopic management is the preferred treatment,whereas percutaneous intervention is an alternative approach.Endoscopic treatment involves mechanical cleaning with a balloon and a second stent insertion as stent-in-stent with either PS or SEMS.Technical feasibility,patient survival and cost-effectiveness are important factors that determine the method of re-drainage and stent selection.
文摘In order to improve the success rate of chronic total occlusion (CTO)percutaneous coronary intervention (PCI), retrograde approach has been attracted more attention.Recent study reported the collateral perforation rate was 6.9% in retrograde CTO PCI.[1,2] Collateral related perforations were higher in patients with the epicardial collateral than that with the septal collateral.[3]Several techniques have been developed to deal with the collateral branch perforation.Here,we described the treatment of epicardial collateral branch perforation by absorbable suture segments embolization through microcatheter during retrograde CTO PCI.
文摘Non-valvular atrial fibrillation is associated with a significantly increased risk of embolic stroke due to blood clot forming predominantly in the left atrial appendage(LAA). Preventive measures to avoid embolic events are permanent administration of anticoagulants or surgical closure of the LAA. Various clinical trials provide evidence about safety, effectiveness and therapeutic success of LAA occlusion using various cardiac occluder devices. The use of such implants for interventional closure of the LAA is likely to become a valuable alternative for stroke prevention, especially in patients with contraindication for oral anticoagulation as safety, clinical benefit and cost-effectiveness of LAA occlusion has recently been demonstrated.
文摘A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly （155 m）. Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46%and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk dis-tance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient’s heart functions.
文摘Video surveillance is an active research topic in computer vision.In this paper,humans and cars identifcation technique suitable for real time video surveillance systems is presented.The technique we proposed includes background subtraction,foreground segmentation,shadow removal,feature extraction and classifcation.The feature extraction of the extracted foreground objects is done via a new set of afne moment invariants based on statistics method and these were used to identify human or car.When the partial occlusion occurs,although features of full body cannot be extracted,our proposed technique extracts the features of head shoulder.Our proposed technique can identify human by extracting the human head-shoulder up to 60%–70%occlusion.Thus,it has a better classifcation to solve the issue of the loss of property arising from human occluded easily in practical applications.The whole system works at approximately 16 29 fps and thus it is suitable for real-time applications.The accuracy for our proposed technique in identifying human is very good,which is 98.33%,while for cars identifcation,the accuracy is also good,which is 94.41%.The overall accuracy for our proposed technique in identifying human and car is at 98.04%.The experiment results show that this method is efective and has strong robustness.
基金financially supported by Jiangsu Graduate Student Innovation Program of China(No.CXZZ-0146)the Scientif ic Research Foundation of Graduate School of Southeast University(No.YBJJ1235)
文摘In order to provide scientific basis for advanced applications of near eutectic Al-Si-Mg alloys as architectural profiles, a comparative study on the corrosion resistance of an as-extruded near eutectic AI-Si-Mg alloy and AA6063 aluminium alloy was carried out by means of neutral salt spray test. The corroded surfaces of the alloys were examined with optical microscopy and scanning electron microscope （SEM）. Results show that the corrosion type of these two alloys is pitting corrosion. The number of corrosion pits in the AA6063 aluminium alloy is more than that in the near eutectic AI-Si-Mg alloy, but the pits in the latter alloy are much larger and deeper. Because the relatively low polarization resistance of the near eutectic alloy leads to poorer repassivation ability, autocatalytic acidification occurs once a pit forms. Thus, occluded corrosion cells are developed in this alloy.
文摘BACKGROUND The off-label use of various devices has been reported for the transcatheter closure of perimembranous ventricular septal defects(PmVSD) because of serious complications, such as heart block and tricuspid regurgitation(TR),associated with conventional ventricular septal defect devices. However, whether certain defects such as PmVSD with abnormally attached tricuspid are fit for interventional treatment is still disputable.AIM To explore the feasibility and safety of transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae using an improved patent ductus arteriosus(PDA) occluder.METHODS We retrospectively analyzed 20 patients diagnosed with PmVSD with abnormally attached tricuspid chordae tendineae who underwent interventional treatment using an improved PDA occluder at our center from January 2012 to January 2016. Baseline characteristics and procedural and follow-up data were analyzed.RESULTS All 20 patients achieved procedure success. No heart block occurred during the operation. One patient had a transient complete right bundle branch block within48 h post-procedure and reverted to normal rhythm after intravenous injections of dexamethasone for 3 d. For all 20 patients, no residual shunt was observed by transthoracic echocardiography post-procedure. During the average follow-up period of 2.4 years, no severe TR was observed.CONCLUSION Using of the improved PDA occluder for the transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae is a safe and promising treatment option. However, long-term follow-up in a large group of patients is still warranted.
基金Project(61172089) supported by the National Natural Science Foundation of China
文摘The difficulty of multiple targets tracking is how to quickly fulfill the target matching from one flame image to another and fix the position of the target. In order to accurately choose target feature information for reliable matching, simplify operations under the reliable precondition, and realize precise moving objects tracking, an approach based on Kalman prediction and feature matching was proposed. The position of the target in next frame image was predicted by Kalman, and then the moving objects of two adjacent frames were matched by the centroid and area methods. When occlusion occurs, the best matching result was found to realize tracking by matching matrix algorithm. The simulation results show that the proposed method can achieve multiple targets tracking accurately and in real-time under complicated motion movements.
文摘AIM To investigate the interaction of Zot withmicrotubule.METHODS Zot affinity column was applied topurify Zot-binding protein（s）from crudeintestinal cell lysates.After incubation at roomtemperature,the column was washed and theproteins bound to the Zot affinity column wereeluted by step gradient with NaCl(0.3 mol·L<sup>-1</sup>-0.5mol·L<sup>-1</sup>).The fractions were subjected to6.0%-15.0%（w/v）gradient SDS-PAGE andthen transferred to PVDF membrane for N-terminal sequencing.Purified Zot and tauprotein were blotted by using anti-Zot or anti-tauantibodies.Finally,purified Zot was tested in anin vitro tubulin binding assay.RESULTS Fractions from Zot affinity columnyielded two protein bands with a Mr of 60 kU and45kU respectively.The N-terminal sequence ofthe 60 kU band resulted identical to β-tubulin.Zot also cross-reacts with anti-tau antibodies.Inthe in vitro tubulin binding assay,Zot co-precipitate with Mt,further suggesting that Zotpossesses tubulin-binding properties.CONCLUSION Taken together,these resultssuggest that Zot regulates the permeability ofintestinal tight junctions by binding tointracellular Mt,with the subsequent activationof the intracellular signaling leading to thepermeabilization of intercellular tight junctions.
