BACKGROUND: Primary intrahepatic cholelithiasis is usually combined with biliary tract infection. This research was undertaken to investigate the relationship between intrahepatic stones and biliary tract infection. M...BACKGROUND: Primary intrahepatic cholelithiasis is usually combined with biliary tract infection. This research was undertaken to investigate the relationship between intrahepatic stones and biliary tract infection. METHODS: Thirty-five bile samples and 30 stones specimens were cultured for bacteria and 12 stones specimens were examined with a scan electron microscope (SEM) or a transmission electron microscope (TEM). RESULT: 94.2% bile samples and 96.7% stones specimens were positive in bacteria culture. Bacteria were found in stones under SEM and TEM. CONCLUSION: Bacteria in stones are associated with the infection of the biliary tract.展开更多
Objective To evaluate the diagnostic value of histopathological examination of ultrasound-guided puncture biopsy samples in extrapulmonary tuberculosis(EPTB).Methods This study was conducted at the Shanghai Public Hea...Objective To evaluate the diagnostic value of histopathological examination of ultrasound-guided puncture biopsy samples in extrapulmonary tuberculosis(EPTB).Methods This study was conducted at the Shanghai Public Health Clinical Center.A total of 115patients underwent ultrasound-guided puncture biopsy,followed by MGIT 960 culture(culture),smear,Gene Xpert MTB/RIF(Xpert),and histopathological examination.These assays were performed to evaluate their effectiveness in diagnosing EPTB in comparison to two different diagnostic criteria:liquid culture and composite reference standard(CRS).Results When CRS was used as the reference standard,the sensitivity and specificity of culture,smear,Xpert,and histopathological examination were(44.83%,89.29%),(51.72%,89.29%),(70.11%,96.43%),and(85.06%,82.14%),respectively.Based on liquid culture tests,the sensitivity and specificity of smear,Xpert,and pathological examination were(66.67%,72.60%),(83.33%,63.01%),and(92.86%,45.21%),respectively.Histopathological examination showed the highest sensitivity but lowest specificity.Further,we found that the combination of Xpert and histopathological examination showed a sensitivity of 90.80%and a specificity of 89.29%.Conclusion Ultrasound-guided puncture sampling is safe and effective for the diagnosis of EPTB.Compared with culture,smear,and Xpert,histopathological examination showed higher sensitivity but lower specificity.The combination of histopathology with Xpert showed the best performance characteristics.展开更多
The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-b...The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave approximation.The target nuclei included both stable and unstable nuclei,and the incident energies reached 200 MeV.The results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 potential.Overall,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive targets.On average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 MeV.However,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.展开更多
Non-melanoma skin cancers or keratinocyte cancers such as basal cell carcinoma and squamous cell carcinoma make up approximately 80% and 20% respectively, of skin cancers with the 6 million people that are treated ann...Non-melanoma skin cancers or keratinocyte cancers such as basal cell carcinoma and squamous cell carcinoma make up approximately 80% and 20% respectively, of skin cancers with the 6 million people that are treated annually in the United States. 1 in 5 Americans and 2 in 3 Australians develop skin cancer by the age of 70 years and in Australia it is the most expensive, amassing $1.5 billion, to treat cancers. Non-melanoma skin cancers are often self-detected and are usually removed by various means in doctors’ surgeries. Mohs micrographic surgery is acclaimed to be the gold standard for the treatment of skin cancer. However, a novel microscopic molecular-cellular non-invasive topical therapy described in this article, challenges the status of Mohs procedure for being the acclaimed gold standard.展开更多
With the reform of the New National College Entrance Examination(Gaokao),the nongraded education will become an inevitable trend.In senior high school,the traditional test-oriented education is popular.The knowledge i...With the reform of the New National College Entrance Examination(Gaokao),the nongraded education will become an inevitable trend.In senior high school,the traditional test-oriented education is popular.The knowledge is mainly taught by the teachers,and the students passively absorb it.This study examines a problem-oriented Socratic experiment in nongraded English teaching in senior high school.The teachers seek output from students,who respond by interpreting questions,fostering critical thinking,and enhancing problem-solving skills.This teaching experiment indicates that the Socratic method has a significant positive effect on cultivating nongraded senior high English students’critical thinking under the New National College Entrance Examination.展开更多
Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,t...Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.展开更多
Transition metal ditellurides(TMTDs)have versatile physical properties,including non-trivial topology,Weyl semimetal states and unique spin texture.Controlled growth of high-quality and large-scale monolayer TMTDs wit...Transition metal ditellurides(TMTDs)have versatile physical properties,including non-trivial topology,Weyl semimetal states and unique spin texture.Controlled growth of high-quality and large-scale monolayer TMTDs with preferred crystal phases is crucial for their applications.Here,we demonstrate the epitaxial growth of 1T'-MoTe_(2) on Au(111)and graphitized silicon carbide(Gr/SiC)by molecular beam epitaxy(MBE).We investigate the morphology of the grown1T'-MoTe_(2) at the atomic level by scanning tunnelling microscopy(STM)and reveal the corresponding microscopic growth mechanism.It is found that the unique ordered Te structures preferentially deposited on Au(111)regulate the growth of monolayer single crystal 1T'-MoTe_(2),while the Mo clusters were preferentially deposited on the Gr/SiC substrate,which impedes the ordered growth of monolayer MoTe_(2).We confirm that the size of single crystal 1T'-MoTe_(2) grown on Au(111)is nearly two orders of magnitude larger than that on Gr/SiC.By scanning tunnelling spectroscopy(STS),we observe that the STS spectrum of the monolayer 1T'-MoTe_(2) nano-island at the edge is different from that at the interior,which exhibits enhanced conductivity.展开更多
This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscop...This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.展开更多
“Introduction to Language,”as the core course of the English major,mainly reveals the basic laws of language,enabling the students to have the ability to apply linguistic theories to explain language phenomena and s...“Introduction to Language,”as the core course of the English major,mainly reveals the basic laws of language,enabling the students to have the ability to apply linguistic theories to explain language phenomena and solve specific language problems.This course is highly theoretical and has a certain degree of difficulty.The evaluation of student grades has always been based on examination reform,but several problems have been encountered during the implementation process.This article analyzes the current situation of the reform and implementation of the“Introduction to Language”course examination in applied universities and puts forth suggestions and specific measures to improve the assessment of the course,aiming to enhance the teaching effectiveness of the course and scientifically and comprehensively evaluate students’abilities.展开更多
In the environment of smart examination rooms, it is important to quickly and accurately detect abnormal behavior(human standing) for the construction of a smart campus. Based on deep learning, we propose an intellige...In the environment of smart examination rooms, it is important to quickly and accurately detect abnormal behavior(human standing) for the construction of a smart campus. Based on deep learning, we propose an intelligentstanding human detection (ISHD) method based on an improved single shot multibox detector to detect thetarget of standing human posture in the scene frame of exam room video surveillance at a specific examinationstage. ISHD combines the MobileNet network in a single shot multibox detector network, improves the posturefeature extractor of a standing person, merges prior knowledge, and introduces transfer learning in the trainingstrategy, which greatly reduces the computation amount, improves the detection accuracy, and reduces the trainingdifficulty. The experiment proves that the model proposed in this paper has a better detection ability for the smalland medium-sized standing human body posture in video test scenes on the EMV-2 dataset.展开更多
In cases of death caused by hypothermia,histological analysis can be used to determine the cause of death.Certain histological alterations of the pituitary glands in hypothermia have been reported in the literature,in...In cases of death caused by hypothermia,histological analysis can be used to determine the cause of death.Certain histological alterations of the pituitary glands in hypothermia have been reported in the literature,including haemorrhage,hyperaemia and cellular vacuolization of cells in the anterior lobe.In the present study,the validity of these morphological alterations as markers for fatal accidental hypothermia was investigated in autopsy material.A total of 34 pituitary glands in cases of verified fatal accidental hypothermia were examined histologically(haematoxylin and eosin,ferric,azan)and immunohistochemically(LCA,ACTH,C5b-9).The findings were compared with 61 cases in a control group.Hyperaemia was found in 50.0%of the study group cases and 59.0% of the control group cases.Cellular vacuolization was observed in one case(2.9%)in the study group and one case(1.6%)in the control group.Acute or recent haemorrhage in the glandular tissue was never detected.In our study,the histopathological characteristics described in the literature as pathognomonic for hypothermia could not be confirmed.Furthermore,histological differences in the pituitary glands between fatal hypothermia cases and control group cases were not observed.展开更多
AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to fac...AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to facilitate the reproduction of a skilled surgeon’s technique by a surgeon in training.METHODS:A small camera was attached to the operating microscope with a custom adapter.Microscopic surgeon’s view and direct surgeon’s view through this new camera were recorded in the surgical recording system.Both movies were synchronized and analyzed how do surgeons handle the instruments.RESULTS:A small camera attached to the operating microscope allowed the surgeon’s hands motion to be recorded without interfering with the surgeon’s movements.Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device.Even in the simple paracentesis procedure,different surgeons used different methods.Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view.CONCLUSION:Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries.展开更多
Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the visi...Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the vision system,an image mosaic technique must be used.In this paper,a method for constructing an image mosaic with non-overlapping areas with enhanced efficiency is proposed.First,an image mosaic model for the part is created using a geometric model of the measurement system installed on a X-Y-Z precision stages with high repeatability,and a path for image acquisition is established.Second,images are captured along the same path for a specified calibration plate,and an entire image is formed based on the given model.The measurement results obtained from the specified calibration plate are utilized to identify mosaic errors and apply compensation for the part requiring measurement.Experimental results show that the maximum error is less than 4μm for a camera with pixel equivalent 2.46μm,thereby demonstrating the accuracy of the proposed method.This image mosaic technique with non-overlapping regions can simplify image acquisition and reduce the workload involved in constructing an image mosaic.展开更多
AIM:To describe the subcutaneous pedicled propeller flap technique for the microscopic reconstruction of eyelid defects and evaluate its outcomes.METHODS:The clinical data of 23 patients(23 eyes)who underwent microsco...AIM:To describe the subcutaneous pedicled propeller flap technique for the microscopic reconstruction of eyelid defects and evaluate its outcomes.METHODS:The clinical data of 23 patients(23 eyes)who underwent microscopic reconstruction of eyelid defects with the subcutaneous pedicled propeller flap technique were retrospectively analyzed.All patients underwent eyelid tumor resection and one-stage microscopic reconstruction with the subcutaneous pedicled propeller flap for anterioror posterior-layer eyelid defects.The survival rate of the propeller flap,eyelid function and appearance,tumor recurrence rate,and patient satisfaction were evaluated after the surgery.RESULTS:The patients consisted of 12 men and 11 women,aged 31–82y(mean,58.9y).The longest followup time was 5y,and the shortest was 3mo.All the propeller flaps survived well.There was no significant difference in color and luster between the flap and adjacent tissues,and there was no dog ear phenomenon.No obvious scarring was observed.There were no obvious abnormalities of eyelid morphology or function,and no adverse complications such as exposure keratitis,entropion,ectropion,ptosis,and eyelid retraction.No tumor recurrence was found at the time of the last follow-up.All patients were satisfied with the surgical results.CONCLUSION:The subcutaneous pedicled propeller flap technique for the microscopic reconstruction of eyelid defects has satisfactor y outcomes in terms of eyelid function and esthetics,and merits clinical application.展开更多
Accurate histopathology classification is a crucial factor in the diagnosis and treatment of Cholangiocarcinoma(CCA).Hyperspectral images(HSI)provide rich spectral information than ordinary RGB images,making them more...Accurate histopathology classification is a crucial factor in the diagnosis and treatment of Cholangiocarcinoma(CCA).Hyperspectral images(HSI)provide rich spectral information than ordinary RGB images,making them more useful for medical diagnosis.The Convolutional Neural Network(CNN)is commonly employed in hyperspectral image classification due to its remarkable capacity for feature extraction and image classification.However,many existing CNN-based HSI classification methods tend to ignore the importance of image spatial context information and the interdependence between spectral channels,leading to unsatisfied classification performance.Thus,to address these issues,this paper proposes a Spatial-Spectral Joint Network(SSJN)model for hyperspectral image classification that utilizes spatial self-attention and spectral feature extraction.The SSJN model is derived from the ResNet18 network and implemented with the non-local and Coordinate Attention(CA)modules,which extract long-range dependencies on image space and enhance spatial features through the Branch Attention(BA)module to emphasize the region of interest.Furthermore,the SSJN model employs Conv-LSTM modules to extract long-range depen-dencies in the image spectral domain.This addresses the gradient disappearance/explosion phenom-ena and enhances the model classification accuracy.The experimental results show that the pro-posed SSJN model is more efficient in leveraging the spatial and spectral information of hyperspec-tral images on multidimensional microspectral datasets of CCA,leading to higher classification accuracy,and may have useful references for medical diagnosis of CCA.展开更多
Traffic simulators are utilized to solve a variety of traffic-related problems.For such simulators,origin-destination(OD)traffic volumes as mobility demands are required to input,and we need to estimate them.The autho...Traffic simulators are utilized to solve a variety of traffic-related problems.For such simulators,origin-destination(OD)traffic volumes as mobility demands are required to input,and we need to estimate them.The authors regard an OD estimation as a bi-level programming problem,and apply a microscopic traffic simulation model to it.However,the simulation trials can be computationally expensive if full dynamic rerouting is allowed,when employing multi-agent-based models in the estimation process.This paper proposes an efficient OD estimation method using a multi-agent-based simulator with restricted dynamic rerouting to reduce the computational load.Even though,in the case of large traffic demand,the restriction on dynamic rerouting can result in heavier congestion.The authors resolve this problem by introducing constraints of the bi-level programming problem depending on link congestion.Test results show that the accuracy of the link traffic volume reproduced with the proposed method is virtually identical to that of existing methods but that the proposed method is more computationally efficient in a wide-range or high-demand context.展开更多
Objective: To evaluate the interest of the simulation in the learning of the obstetric examination of parturient by medical students. Materials and methods: It was an analytical cross-sectional study that took place f...Objective: To evaluate the interest of the simulation in the learning of the obstetric examination of parturient by medical students. Materials and methods: It was an analytical cross-sectional study that took place from 1 to 28 February 2020 at the Yalgado Ouedraogo Teaching Hospital in Ouagadougou, Burkina Faso. The study population was made up of medical students at the Doctorate II level. The previous experience of the students in the obstetric examination of the parturient, the contribution of the simulation on their feelings and on their skills towards this examination were studied. The Mc Nemar Chi<sup>2</sup> test was used to compare percentages on paired samples. Results: The level of difficulty in performing the obstetrical examination in the parturient evolved downwards after the practice of the simulation. The stress level to perform the obstetric exam has been significantly reduced. On the other hand, confidence has increased. The students’ ability to appreciate each of the elements of the obstetric examination studied had improved after the practice of simulation. Conclusion: The simulation in the skills laboratory was a great contribution and the acquisition of models of better fidelity would help to improve the contribution to the confidence building and the acquisition of skills by learners.展开更多
文摘BACKGROUND: Primary intrahepatic cholelithiasis is usually combined with biliary tract infection. This research was undertaken to investigate the relationship between intrahepatic stones and biliary tract infection. METHODS: Thirty-five bile samples and 30 stones specimens were cultured for bacteria and 12 stones specimens were examined with a scan electron microscope (SEM) or a transmission electron microscope (TEM). RESULT: 94.2% bile samples and 96.7% stones specimens were positive in bacteria culture. Bacteria were found in stones under SEM and TEM. CONCLUSION: Bacteria in stones are associated with the infection of the biliary tract.
基金funded by the grants from the National Key Research and Development Program of China[2021YFC2301503,2022YFC2302900]the National Natural and Science Foundation of China[82171739,82171815,81873884]。
文摘Objective To evaluate the diagnostic value of histopathological examination of ultrasound-guided puncture biopsy samples in extrapulmonary tuberculosis(EPTB).Methods This study was conducted at the Shanghai Public Health Clinical Center.A total of 115patients underwent ultrasound-guided puncture biopsy,followed by MGIT 960 culture(culture),smear,Gene Xpert MTB/RIF(Xpert),and histopathological examination.These assays were performed to evaluate their effectiveness in diagnosing EPTB in comparison to two different diagnostic criteria:liquid culture and composite reference standard(CRS).Results When CRS was used as the reference standard,the sensitivity and specificity of culture,smear,Xpert,and histopathological examination were(44.83%,89.29%),(51.72%,89.29%),(70.11%,96.43%),and(85.06%,82.14%),respectively.Based on liquid culture tests,the sensitivity and specificity of smear,Xpert,and pathological examination were(66.67%,72.60%),(83.33%,63.01%),and(92.86%,45.21%),respectively.Histopathological examination showed the highest sensitivity but lowest specificity.Further,we found that the combination of Xpert and histopathological examination showed a sensitivity of 90.80%and a specificity of 89.29%.Conclusion Ultrasound-guided puncture sampling is safe and effective for the diagnosis of EPTB.Compared with culture,smear,and Xpert,histopathological examination showed higher sensitivity but lower specificity.The combination of histopathology with Xpert showed the best performance characteristics.
基金Supported by National Natural Science Foundation of China(Nos.U2067205 and 12205098)National Key Laboratory of Computational Physics(HX02021-35).
文摘The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave approximation.The target nuclei included both stable and unstable nuclei,and the incident energies reached 200 MeV.The results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 potential.Overall,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive targets.On average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 MeV.However,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.
文摘Non-melanoma skin cancers or keratinocyte cancers such as basal cell carcinoma and squamous cell carcinoma make up approximately 80% and 20% respectively, of skin cancers with the 6 million people that are treated annually in the United States. 1 in 5 Americans and 2 in 3 Australians develop skin cancer by the age of 70 years and in Australia it is the most expensive, amassing $1.5 billion, to treat cancers. Non-melanoma skin cancers are often self-detected and are usually removed by various means in doctors’ surgeries. Mohs micrographic surgery is acclaimed to be the gold standard for the treatment of skin cancer. However, a novel microscopic molecular-cellular non-invasive topical therapy described in this article, challenges the status of Mohs procedure for being the acclaimed gold standard.
基金This research is funded by 2021 Postgraduate Scientific Research Innovation Project of Hunan Province Key Project—Diagnosis and Evaluation of High School Students’Critical Thinking Quality in English(Project approval No.QL20210120)the 2022 Hunan Province General Higher Education Teaching Reform Research Project—Research on the Cultivation Path of English Learners’Critical Thinking Ability From the Perspective of Curriculum Ideology and Politics(Project Approval No.HNJG-2022-1299).
文摘With the reform of the New National College Entrance Examination(Gaokao),the nongraded education will become an inevitable trend.In senior high school,the traditional test-oriented education is popular.The knowledge is mainly taught by the teachers,and the students passively absorb it.This study examines a problem-oriented Socratic experiment in nongraded English teaching in senior high school.The teachers seek output from students,who respond by interpreting questions,fostering critical thinking,and enhancing problem-solving skills.This teaching experiment indicates that the Socratic method has a significant positive effect on cultivating nongraded senior high English students’critical thinking under the New National College Entrance Examination.
基金supported by the China Scholarship Council (CSC) (No.202206020149)the Academic Excellence Foundation of BUAA for PhD Students,the Funding Project of Science and Technology on Reliability and Environmental Engineering Laboratory (No.6142004210106).
文摘Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.
基金Project supported by the National Key R&D Program of China (Grant No.2022YFA1204302)the National Natural Science Foundation of China (Grant Nos.52022029,52221001,92263107,U23A20570,62090035,U19A2090,and 12174098)+1 种基金the Hunan Provincial Natural Science Foundation of China (Grant Nos.2022JJ30142 and 2019XK2001)in part supported by the State Key Laboratory of Powder Metallurgy,Central South University。
文摘Transition metal ditellurides(TMTDs)have versatile physical properties,including non-trivial topology,Weyl semimetal states and unique spin texture.Controlled growth of high-quality and large-scale monolayer TMTDs with preferred crystal phases is crucial for their applications.Here,we demonstrate the epitaxial growth of 1T'-MoTe_(2) on Au(111)and graphitized silicon carbide(Gr/SiC)by molecular beam epitaxy(MBE).We investigate the morphology of the grown1T'-MoTe_(2) at the atomic level by scanning tunnelling microscopy(STM)and reveal the corresponding microscopic growth mechanism.It is found that the unique ordered Te structures preferentially deposited on Au(111)regulate the growth of monolayer single crystal 1T'-MoTe_(2),while the Mo clusters were preferentially deposited on the Gr/SiC substrate,which impedes the ordered growth of monolayer MoTe_(2).We confirm that the size of single crystal 1T'-MoTe_(2) grown on Au(111)is nearly two orders of magnitude larger than that on Gr/SiC.By scanning tunnelling spectroscopy(STS),we observe that the STS spectrum of the monolayer 1T'-MoTe_(2) nano-island at the edge is different from that at the interior,which exhibits enhanced conductivity.
基金Supported by the National Natural Science Foundation of China(52234003,52222402,52304044).
文摘This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.
基金Second batch of“opening bidding”Wuhan University of Bioengineering“Research on the Evaluation of the Implementation Effect of Curriculum Examination Reform:Taking the Course of Introduction to Language as an Example”(No.2023JGYB37)。
文摘“Introduction to Language,”as the core course of the English major,mainly reveals the basic laws of language,enabling the students to have the ability to apply linguistic theories to explain language phenomena and solve specific language problems.This course is highly theoretical and has a certain degree of difficulty.The evaluation of student grades has always been based on examination reform,but several problems have been encountered during the implementation process.This article analyzes the current situation of the reform and implementation of the“Introduction to Language”course examination in applied universities and puts forth suggestions and specific measures to improve the assessment of the course,aiming to enhance the teaching effectiveness of the course and scientifically and comprehensively evaluate students’abilities.
基金supported by the Natural Science Foundation of China 62102147National Science Foundation of Hunan Province 2022JJ30424,2022JJ50253,and 2022JJ30275+2 种基金Scientific Research Project of Hunan Provincial Department of Education 21B0616 and 21B0738Hunan University of Arts and Sciences Ph.D.Start-Up Project BSQD02,20BSQD13the Construct Program of Applied Characteristic Discipline in Hunan University of Science and Engineering.
文摘In the environment of smart examination rooms, it is important to quickly and accurately detect abnormal behavior(human standing) for the construction of a smart campus. Based on deep learning, we propose an intelligentstanding human detection (ISHD) method based on an improved single shot multibox detector to detect thetarget of standing human posture in the scene frame of exam room video surveillance at a specific examinationstage. ISHD combines the MobileNet network in a single shot multibox detector network, improves the posturefeature extractor of a standing person, merges prior knowledge, and introduces transfer learning in the trainingstrategy, which greatly reduces the computation amount, improves the detection accuracy, and reduces the trainingdifficulty. The experiment proves that the model proposed in this paper has a better detection ability for the smalland medium-sized standing human body posture in video test scenes on the EMV-2 dataset.
文摘In cases of death caused by hypothermia,histological analysis can be used to determine the cause of death.Certain histological alterations of the pituitary glands in hypothermia have been reported in the literature,including haemorrhage,hyperaemia and cellular vacuolization of cells in the anterior lobe.In the present study,the validity of these morphological alterations as markers for fatal accidental hypothermia was investigated in autopsy material.A total of 34 pituitary glands in cases of verified fatal accidental hypothermia were examined histologically(haematoxylin and eosin,ferric,azan)and immunohistochemically(LCA,ACTH,C5b-9).The findings were compared with 61 cases in a control group.Hyperaemia was found in 50.0%of the study group cases and 59.0% of the control group cases.Cellular vacuolization was observed in one case(2.9%)in the study group and one case(1.6%)in the control group.Acute or recent haemorrhage in the glandular tissue was never detected.In our study,the histopathological characteristics described in the literature as pathognomonic for hypothermia could not be confirmed.Furthermore,histological differences in the pituitary glands between fatal hypothermia cases and control group cases were not observed.
文摘AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to facilitate the reproduction of a skilled surgeon’s technique by a surgeon in training.METHODS:A small camera was attached to the operating microscope with a custom adapter.Microscopic surgeon’s view and direct surgeon’s view through this new camera were recorded in the surgical recording system.Both movies were synchronized and analyzed how do surgeons handle the instruments.RESULTS:A small camera attached to the operating microscope allowed the surgeon’s hands motion to be recorded without interfering with the surgeon’s movements.Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device.Even in the simple paracentesis procedure,different surgeons used different methods.Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view.CONCLUSION:Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries.
基金supported by the Liaoning Revitalization Talents Program(Grant No.XLYC2002020)the Major Project of Basic Scientific Research of Chinese Ministry(Grant No.JCYK2016205A003).
文摘Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the vision system,an image mosaic technique must be used.In this paper,a method for constructing an image mosaic with non-overlapping areas with enhanced efficiency is proposed.First,an image mosaic model for the part is created using a geometric model of the measurement system installed on a X-Y-Z precision stages with high repeatability,and a path for image acquisition is established.Second,images are captured along the same path for a specified calibration plate,and an entire image is formed based on the given model.The measurement results obtained from the specified calibration plate are utilized to identify mosaic errors and apply compensation for the part requiring measurement.Experimental results show that the maximum error is less than 4μm for a camera with pixel equivalent 2.46μm,thereby demonstrating the accuracy of the proposed method.This image mosaic technique with non-overlapping regions can simplify image acquisition and reduce the workload involved in constructing an image mosaic.
基金Supported by the Young Talent Program of Gusu Health Project(No.GSWS2020014)。
文摘AIM:To describe the subcutaneous pedicled propeller flap technique for the microscopic reconstruction of eyelid defects and evaluate its outcomes.METHODS:The clinical data of 23 patients(23 eyes)who underwent microscopic reconstruction of eyelid defects with the subcutaneous pedicled propeller flap technique were retrospectively analyzed.All patients underwent eyelid tumor resection and one-stage microscopic reconstruction with the subcutaneous pedicled propeller flap for anterioror posterior-layer eyelid defects.The survival rate of the propeller flap,eyelid function and appearance,tumor recurrence rate,and patient satisfaction were evaluated after the surgery.RESULTS:The patients consisted of 12 men and 11 women,aged 31–82y(mean,58.9y).The longest followup time was 5y,and the shortest was 3mo.All the propeller flaps survived well.There was no significant difference in color and luster between the flap and adjacent tissues,and there was no dog ear phenomenon.No obvious scarring was observed.There were no obvious abnormalities of eyelid morphology or function,and no adverse complications such as exposure keratitis,entropion,ectropion,ptosis,and eyelid retraction.No tumor recurrence was found at the time of the last follow-up.All patients were satisfied with the surgical results.CONCLUSION:The subcutaneous pedicled propeller flap technique for the microscopic reconstruction of eyelid defects has satisfactor y outcomes in terms of eyelid function and esthetics,and merits clinical application.
基金supported by National Natural Science Foundation of China(No.62101040).
文摘Accurate histopathology classification is a crucial factor in the diagnosis and treatment of Cholangiocarcinoma(CCA).Hyperspectral images(HSI)provide rich spectral information than ordinary RGB images,making them more useful for medical diagnosis.The Convolutional Neural Network(CNN)is commonly employed in hyperspectral image classification due to its remarkable capacity for feature extraction and image classification.However,many existing CNN-based HSI classification methods tend to ignore the importance of image spatial context information and the interdependence between spectral channels,leading to unsatisfied classification performance.Thus,to address these issues,this paper proposes a Spatial-Spectral Joint Network(SSJN)model for hyperspectral image classification that utilizes spatial self-attention and spectral feature extraction.The SSJN model is derived from the ResNet18 network and implemented with the non-local and Coordinate Attention(CA)modules,which extract long-range dependencies on image space and enhance spatial features through the Branch Attention(BA)module to emphasize the region of interest.Furthermore,the SSJN model employs Conv-LSTM modules to extract long-range depen-dencies in the image spectral domain.This addresses the gradient disappearance/explosion phenom-ena and enhances the model classification accuracy.The experimental results show that the pro-posed SSJN model is more efficient in leveraging the spatial and spectral information of hyperspec-tral images on multidimensional microspectral datasets of CCA,leading to higher classification accuracy,and may have useful references for medical diagnosis of CCA.
基金supported by JSPS KAKENHI (Grant Nos.15H01785 and 19H02377).
文摘Traffic simulators are utilized to solve a variety of traffic-related problems.For such simulators,origin-destination(OD)traffic volumes as mobility demands are required to input,and we need to estimate them.The authors regard an OD estimation as a bi-level programming problem,and apply a microscopic traffic simulation model to it.However,the simulation trials can be computationally expensive if full dynamic rerouting is allowed,when employing multi-agent-based models in the estimation process.This paper proposes an efficient OD estimation method using a multi-agent-based simulator with restricted dynamic rerouting to reduce the computational load.Even though,in the case of large traffic demand,the restriction on dynamic rerouting can result in heavier congestion.The authors resolve this problem by introducing constraints of the bi-level programming problem depending on link congestion.Test results show that the accuracy of the link traffic volume reproduced with the proposed method is virtually identical to that of existing methods but that the proposed method is more computationally efficient in a wide-range or high-demand context.
文摘Objective: To evaluate the interest of the simulation in the learning of the obstetric examination of parturient by medical students. Materials and methods: It was an analytical cross-sectional study that took place from 1 to 28 February 2020 at the Yalgado Ouedraogo Teaching Hospital in Ouagadougou, Burkina Faso. The study population was made up of medical students at the Doctorate II level. The previous experience of the students in the obstetric examination of the parturient, the contribution of the simulation on their feelings and on their skills towards this examination were studied. The Mc Nemar Chi<sup>2</sup> test was used to compare percentages on paired samples. Results: The level of difficulty in performing the obstetrical examination in the parturient evolved downwards after the practice of the simulation. The stress level to perform the obstetric exam has been significantly reduced. On the other hand, confidence has increased. The students’ ability to appreciate each of the elements of the obstetric examination studied had improved after the practice of simulation. Conclusion: The simulation in the skills laboratory was a great contribution and the acquisition of models of better fidelity would help to improve the contribution to the confidence building and the acquisition of skills by learners.
