BACKGROUND The etiological diagnosis of intracranial hypertension is quite complicated but important in clinical practice.Some common causes are craniocerebral injury,intracranial space-occupying lesion,subarachnoid h...BACKGROUND The etiological diagnosis of intracranial hypertension is quite complicated but important in clinical practice.Some common causes are craniocerebral injury,intracranial space-occupying lesion,subarachnoid hemorrhage,and hydrocephalus.When a patient presents with intracranial hypertension,the common causes are to be considered first so that other causes would be dismissed.With the morbidity lower than 9%,neuromelanin is very rare.Common symp-toms include nerve damage symptoms,epilepsy,psychiatric symptoms,and cognitive disorders.CASE SUMMARY We present a patient with melanoma which manifested with isolated intracranial hypertension without any other neurological signs.A 22-year-old male had repeated nausea and vomiting for 2 mo with Babinski sign(+)on both sides,nuchal rigidity,and subarachnoid hemorrhage.He had been diagnosed with melanoma and was given surgery and whole-brain radiation.Ultimately,the patient died 2 mo later.CONCLUSION Malignant melanoma should be taken into consideration in the differential diagnosis of intracranial hypertension.展开更多
In this study,a novel equivalent damping ratio model that is suitable for reinforced concrete(RC)structures considering cyclic degradation behavior is developed,and a new equivalent linearization analysis method for i...In this study,a novel equivalent damping ratio model that is suitable for reinforced concrete(RC)structures considering cyclic degradation behavior is developed,and a new equivalent linearization analysis method for implementing the proposed equivalent damping ratio model for use in seismic damage evaluation is presented.To this end,Ibarra’s peak-oriented model,which incorporates an energy-based degradation rule,is selected for representing hysteretic behavior of RC structure,and the optimized equivalent damping for predicting the maximum displacement response is presented by using the empirical method,in which the effect of cyclic degradation is considered.Moreover,the relationship between the hysteretic energy dissipation of the inelastic system and the elastic strain energy of the equivalent linear system is established so that the proposed equivalent linear system can be directly integrated with the Park-Ang seismic model to implement seismic damage evaluation.Due to the simplicity of the equivalent linearization method,the proposed method provides an efficient and reliable way of obtaining comprehensive insight into the seismic performance of RC structures.The verification demonstrates the validity of the proposed method.展开更多
BACKGROUND Endoscopy artifacts are widespread in real capsule endoscopy(CE)images but not in high-quality standard datasets.AIM To improve the segmentation performance of polyps from CE images with artifacts based on ...BACKGROUND Endoscopy artifacts are widespread in real capsule endoscopy(CE)images but not in high-quality standard datasets.AIM To improve the segmentation performance of polyps from CE images with artifacts based on ensemble learning.METHODS We collected 277 polyp images with CE artifacts from 5760 h of videos from 480 patients at Guangzhou First People’s Hospital from January 2016 to December 2019.Two public high-quality standard external datasets were retrieved and used for the comparison experiments.For each dataset,we randomly segmented the data into training,validation,and testing sets for model training,selection,and testing.We compared the performance of the base models and the ensemble model in segmenting polyps from images with artifacts.RESULTS The performance of the semantic segmentation model was affected by artifacts in the sample images,which also affected the results of polyp detection by CE using a single model.The evaluation based on real datasets with artifacts and standard datasets showed that the ensemble model of all state-of-the-art models performed better than the best corresponding base learner on the real dataset with artifacts.Compared with the corresponding optimal base learners,the intersection over union(IoU)and dice of the ensemble learning model increased to different degrees,ranging from 0.08%to 7.01%and 0.61%to 4.93%,respectively.Moreover,in the standard datasets without artifacts,most of the ensemble models were slightly better than the base learner,as demonstrated by the IoU and dice increases ranging from-0.28%to 1.20%and-0.61%to 0.76%,respectively.CONCLUSION Ensemble learning can improve the segmentation accuracy of polyps from CE images with artifacts.Our results demonstrated an improvement in the detection rate of polyps with interference from artifacts.展开更多
High-nickel single-crystal layered oxide material has become the most promising cathode material for electric vehicle power battery due to its high energy density.However,this material still suffers from structural de...High-nickel single-crystal layered oxide material has become the most promising cathode material for electric vehicle power battery due to its high energy density.However,this material still suffers from structural degradation during cycling and especially the severe interfacial reactions at elevated temperatures that exacerbate irreversible capacity loss.Here,a simple strategy was used to construct a dualfunction Li_(1.5)Al_(0.5)Ge_(1.5)P_(3)O_(12)(LAGP)protective layer on the surface of the high-nickel single-crystal(SC)cathode material,leading to SC@LAGP material.The strong Al-O bonding effectively inhibits the release of lattice oxygen(O)at elevated temperatures,which is supported by the positive formation energy of O vacancy from first-principal calculations.Besides,theoretical calculations demonstrate that the appropriate amount of Al doping accelerates the electron and Li^(+)transport,and thus reduces the kinetic barriers.In addition,the LAGP protective layer alleviates the stress accumulation during cycling and effectively reduces the erosion of materials from the electrolyte decomposition at elevated temperatures.The obtained SC@LAGP cathode material demonstrates much enhanced cycling stability even at high voltage(4.6 V)and elevated temperature(55℃),with a high capacity retention of 91.3%after 100 cycles.This work reports a simple dual-function coating strategy that simultaneously stabilizes the structure and interface of the single-crystal cathode material,which can be applied to design other cathode materials.展开更多
We perform density functional theory calculations to investigate the polaron pair （charge transfer state） photo-generation in donor-acceptor oligomer methyl-capped （4,7- benzo[2,1,3]thiadiazole-2,6-（4,4-bis（2-eth...We perform density functional theory calculations to investigate the polaron pair （charge transfer state） photo-generation in donor-acceptor oligomer methyl-capped （4,7- benzo[2,1,3]thiadiazole-2,6-（4,4-bis（2-ethylhexyl）-4H-cyclopent a[1,2-b;3,4-b＇]dithiophene-4, 7-benzo[2,1,3]thiadiazole） （CPDTBT）. Results show that effective photo-generation of charge transfer state can happen in CPDTBT dimer when the group 4,7-benzo[2,1,3]thiadiazole （BT） in one monomer deviates against the conjugated plane （onset torsion angle is about 20°）. The lower excitation energy （530 nm） can only generate the intramolecular excitonic state, while the higher excitation energy （370 nm） can generate the intermolecular charge transfer state, in good agreement with the experiment. Moreover, the mechanism of charge separation in CPDTBT oligorners is discussed.展开更多
The phase structure and morphology of polypropylene （iPP） blends with poly（decamethylene sebacamide （polyamide 1010, PA 1010） and the part-compatible alloys （iPP/PA 1010/iPP-g-MAH） are investigated by Rayleigh ...The phase structure and morphology of polypropylene （iPP） blends with poly（decamethylene sebacamide （polyamide 1010, PA 1010） and the part-compatible alloys （iPP/PA 1010/iPP-g-MAH） are investigated by Rayleigh scattering, i.e. small angle light scattering （SALS）. The structure parameters of SALS, i.e. correlation distance, ac and average chord lengths, /, are calculated. Their variation with the composition of the blends and alloys is discussed. The morphology and structure of fracture surfaces in the blends and alloys are studied by SEM images. The average diameter of dispersed phase in the blends and alloys is calculated by graph processing. The variation of average diameter is similar as that of average chord lengths of dispersed phases. The mechanical properties of the blends and alloys are analyzed and the relation of modulus and yield stress with the composition is studied. It is confirmed that the correlation between the modulus and the structure parameters is non-linear, while the correlation between the yield stress and the composition or structure parameters is linear.展开更多
Big-data analysis of phase-formation rules of high-entropy alloys（HEAs）was conducted and a phase formation rule from a dynamic view was deduced.It was indicated in literatures that cooling rate has a strong influenc...Big-data analysis of phase-formation rules of high-entropy alloys（HEAs）was conducted and a phase formation rule from a dynamic view was deduced.It was indicated in literatures that cooling rate has a strong influence on the phase formation of HEAs.Higher cooling rate may promote the generation of amorphous phase,and accordingly suppress the formation of intermetallics.Meanwhile,it was also shown that cooling rate had little impact on the formation of solid-solution phase.To demonstrate this rule,a series of FeCoNi（AlSiB）xHEAs ribbons were fabricated by a melt-spinning technique,and the microstructure,mechanical,and magnetic properties were also investigated.The results show that all ribbons exhibit disordered solid-solution structure.The addition of boron changes the alloy from ductility to brittleness,but without evident change of magnetic properties.The alloy in the nominal composition of FeCoNi（AlSi）0.2has the best combination of mechanical and magnetic properties.A distinct feature of HEAs in magnetization was noticed and explained.展开更多
文摘BACKGROUND The etiological diagnosis of intracranial hypertension is quite complicated but important in clinical practice.Some common causes are craniocerebral injury,intracranial space-occupying lesion,subarachnoid hemorrhage,and hydrocephalus.When a patient presents with intracranial hypertension,the common causes are to be considered first so that other causes would be dismissed.With the morbidity lower than 9%,neuromelanin is very rare.Common symp-toms include nerve damage symptoms,epilepsy,psychiatric symptoms,and cognitive disorders.CASE SUMMARY We present a patient with melanoma which manifested with isolated intracranial hypertension without any other neurological signs.A 22-year-old male had repeated nausea and vomiting for 2 mo with Babinski sign(+)on both sides,nuchal rigidity,and subarachnoid hemorrhage.He had been diagnosed with melanoma and was given surgery and whole-brain radiation.Ultimately,the patient died 2 mo later.CONCLUSION Malignant melanoma should be taken into consideration in the differential diagnosis of intracranial hypertension.
基金National Natural Science Foundation of China under Grant No.51978125Open Fund Project of Research Center for Geotechnical and Structural Engineering Technology of Liaoning Province under Grant No.DLSZD2023[007]。
文摘In this study,a novel equivalent damping ratio model that is suitable for reinforced concrete(RC)structures considering cyclic degradation behavior is developed,and a new equivalent linearization analysis method for implementing the proposed equivalent damping ratio model for use in seismic damage evaluation is presented.To this end,Ibarra’s peak-oriented model,which incorporates an energy-based degradation rule,is selected for representing hysteretic behavior of RC structure,and the optimized equivalent damping for predicting the maximum displacement response is presented by using the empirical method,in which the effect of cyclic degradation is considered.Moreover,the relationship between the hysteretic energy dissipation of the inelastic system and the elastic strain energy of the equivalent linear system is established so that the proposed equivalent linear system can be directly integrated with the Park-Ang seismic model to implement seismic damage evaluation.Due to the simplicity of the equivalent linearization method,the proposed method provides an efficient and reliable way of obtaining comprehensive insight into the seismic performance of RC structures.The verification demonstrates the validity of the proposed method.
文摘BACKGROUND Endoscopy artifacts are widespread in real capsule endoscopy(CE)images but not in high-quality standard datasets.AIM To improve the segmentation performance of polyps from CE images with artifacts based on ensemble learning.METHODS We collected 277 polyp images with CE artifacts from 5760 h of videos from 480 patients at Guangzhou First People’s Hospital from January 2016 to December 2019.Two public high-quality standard external datasets were retrieved and used for the comparison experiments.For each dataset,we randomly segmented the data into training,validation,and testing sets for model training,selection,and testing.We compared the performance of the base models and the ensemble model in segmenting polyps from images with artifacts.RESULTS The performance of the semantic segmentation model was affected by artifacts in the sample images,which also affected the results of polyp detection by CE using a single model.The evaluation based on real datasets with artifacts and standard datasets showed that the ensemble model of all state-of-the-art models performed better than the best corresponding base learner on the real dataset with artifacts.Compared with the corresponding optimal base learners,the intersection over union(IoU)and dice of the ensemble learning model increased to different degrees,ranging from 0.08%to 7.01%and 0.61%to 4.93%,respectively.Moreover,in the standard datasets without artifacts,most of the ensemble models were slightly better than the base learner,as demonstrated by the IoU and dice increases ranging from-0.28%to 1.20%and-0.61%to 0.76%,respectively.CONCLUSION Ensemble learning can improve the segmentation accuracy of polyps from CE images with artifacts.Our results demonstrated an improvement in the detection rate of polyps with interference from artifacts.
基金financially supported by the National Natural Science Foundation of China(51974368,51774333)the Hunan Provincial Natural Science Foundation of China(2020JJ2048)。
文摘High-nickel single-crystal layered oxide material has become the most promising cathode material for electric vehicle power battery due to its high energy density.However,this material still suffers from structural degradation during cycling and especially the severe interfacial reactions at elevated temperatures that exacerbate irreversible capacity loss.Here,a simple strategy was used to construct a dualfunction Li_(1.5)Al_(0.5)Ge_(1.5)P_(3)O_(12)(LAGP)protective layer on the surface of the high-nickel single-crystal(SC)cathode material,leading to SC@LAGP material.The strong Al-O bonding effectively inhibits the release of lattice oxygen(O)at elevated temperatures,which is supported by the positive formation energy of O vacancy from first-principal calculations.Besides,theoretical calculations demonstrate that the appropriate amount of Al doping accelerates the electron and Li^(+)transport,and thus reduces the kinetic barriers.In addition,the LAGP protective layer alleviates the stress accumulation during cycling and effectively reduces the erosion of materials from the electrolyte decomposition at elevated temperatures.The obtained SC@LAGP cathode material demonstrates much enhanced cycling stability even at high voltage(4.6 V)and elevated temperature(55℃),with a high capacity retention of 91.3%after 100 cycles.This work reports a simple dual-function coating strategy that simultaneously stabilizes the structure and interface of the single-crystal cathode material,which can be applied to design other cathode materials.
基金supported by the National Natural Science Foundation of China (No.21473092)the Jiangsu Province Production and Joint Innovation Fund-Prospective Joint Research Project (No. BY2014007-01)
文摘We perform density functional theory calculations to investigate the polaron pair （charge transfer state） photo-generation in donor-acceptor oligomer methyl-capped （4,7- benzo[2,1,3]thiadiazole-2,6-（4,4-bis（2-ethylhexyl）-4H-cyclopent a[1,2-b;3,4-b＇]dithiophene-4, 7-benzo[2,1,3]thiadiazole） （CPDTBT）. Results show that effective photo-generation of charge transfer state can happen in CPDTBT dimer when the group 4,7-benzo[2,1,3]thiadiazole （BT） in one monomer deviates against the conjugated plane （onset torsion angle is about 20°）. The lower excitation energy （530 nm） can only generate the intramolecular excitonic state, while the higher excitation energy （370 nm） can generate the intermolecular charge transfer state, in good agreement with the experiment. Moreover, the mechanism of charge separation in CPDTBT oligorners is discussed.
文摘The phase structure and morphology of polypropylene （iPP） blends with poly（decamethylene sebacamide （polyamide 1010, PA 1010） and the part-compatible alloys （iPP/PA 1010/iPP-g-MAH） are investigated by Rayleigh scattering, i.e. small angle light scattering （SALS）. The structure parameters of SALS, i.e. correlation distance, ac and average chord lengths, /, are calculated. Their variation with the composition of the blends and alloys is discussed. The morphology and structure of fracture surfaces in the blends and alloys are studied by SEM images. The average diameter of dispersed phase in the blends and alloys is calculated by graph processing. The variation of average diameter is similar as that of average chord lengths of dispersed phases. The mechanical properties of the blends and alloys are analyzed and the relation of modulus and yield stress with the composition is studied. It is confirmed that the correlation between the modulus and the structure parameters is non-linear, while the correlation between the yield stress and the composition or structure parameters is linear.
基金the financial support by National Natural Science Foundation of China(NSFC,Grant No.51471025,No.51671020,and 51471024)
文摘Big-data analysis of phase-formation rules of high-entropy alloys（HEAs）was conducted and a phase formation rule from a dynamic view was deduced.It was indicated in literatures that cooling rate has a strong influence on the phase formation of HEAs.Higher cooling rate may promote the generation of amorphous phase,and accordingly suppress the formation of intermetallics.Meanwhile,it was also shown that cooling rate had little impact on the formation of solid-solution phase.To demonstrate this rule,a series of FeCoNi（AlSiB）xHEAs ribbons were fabricated by a melt-spinning technique,and the microstructure,mechanical,and magnetic properties were also investigated.The results show that all ribbons exhibit disordered solid-solution structure.The addition of boron changes the alloy from ductility to brittleness,but without evident change of magnetic properties.The alloy in the nominal composition of FeCoNi（AlSi）0.2has the best combination of mechanical and magnetic properties.A distinct feature of HEAs in magnetization was noticed and explained.
