From the seeds of Peganum harmala L.,three new alkaloids ofβ-carboline were isolated.Among them,peganumiums A(1)and B(2)were dimers with specific new scaffolds,all with long conjugated systems.Peganumium A and peganu...From the seeds of Peganum harmala L.,three new alkaloids ofβ-carboline were isolated.Among them,peganumiums A(1)and B(2)were dimers with specific new scaffolds,all with long conjugated systems.Peganumium A and peganumium C(3)were ionic alkaloid salts and peganumium B was a hexacycliccondensed alkaloid.The biosynthetic pathways of the three compounds above were also speculated.A preliminary cytotoxicity assay revealed that peganumium B had strong in vitro antiproliferative ability against a variety of cancer cells.The analysis of^(1)H nuclear magnetic resonance(NMR)metabolomics suggested that the antiproliferative mechanism of peganumium B could be associated with the biosynthesis of phenylalanine,tyrosine and tryptophan,the metabolism of glycine,serine,and threonine,the metabolism of taurine and hypotaurine,and the metabolism of nicotinate and nicotinamide.In addition,peganumium B could reduce the mitochondrial content of body-wall muscle cells of a Caenorhabditis elegans(C.elegans)strain in vivo.展开更多
Objective:To explore a simple method for improving the diagnostic accuracy of malignant lung nodules based on imaging features of lung nodules.Methods:A retrospective analysis was conducted on the imaging data of 114 ...Objective:To explore a simple method for improving the diagnostic accuracy of malignant lung nodules based on imaging features of lung nodules.Methods:A retrospective analysis was conducted on the imaging data of 114 patients who underwent lung nodule surgery in the Thoracic Surgery Department of the First People’s Hospital of Huzhou from June to September 2024.Imaging features of lung nodules were summarized and trained using a BP neural network.Results:Training with the BP neural network increased the diagnostic accuracy for distinguishing between benign and malignant lung nodules based on imaging features from 84.2%(manual assessment)to 94.1%.Conclusion:Training with the BP neural network significantly improves the diagnostic accuracy of lung nodule malignancy based solely on imaging features.展开更多
We conducted a rapid seismic intensity assessment of a M 6.8 earthquake in Dingri,Xizang,using a ground motion parameter attenuation model based on the shortest fault distance combined with either an empirical equatio...We conducted a rapid seismic intensity assessment of a M 6.8 earthquake in Dingri,Xizang,using a ground motion parameter attenuation model based on the shortest fault distance combined with either an empirical equation for the surface rupture length or data on the aftershocks that occurred within 1.5 hr after the earthquake.The assessment showed that the empirical equation for the relationship between the surface rupture length and magnitude established by Wells et al.yielded a surface rupture length that was closer to the actual value,while the seismic intensity determined using a combination of the ground motion parameter attenuation model and the empirical equation for the surface rupture length was relatively in line with the intensity from the actual investigation.This study also demonstrated that manual intervention and screening are needed for aftershocks within 1.5 hr after the earthquake if this information is to be employed in the intensity assessment.In addition,if the death assessment model does not consider the seismic vulnerability of local buildings,significant errors can occur in practice.Nevertheless,the disaster assessment results were obtained within 5 min after the earthquake,thus providing important data support for the government emergency command and decision-making associated with the emergency rescue response.展开更多
Anthocyanins and flavonols have vital roles in flower coloration,plant development,and defense.Because anthocyanins and flavonols share the same subcellular localization and common biosynthetic substrates,these pathwa...Anthocyanins and flavonols have vital roles in flower coloration,plant development,and defense.Because anthocyanins and flavonols share the same subcellular localization and common biosynthetic substrates,these pathways may compete for substrates.However,the mechanism regulating this potential competition remains unclear.Here,we identified GhMYB1a,an R2R3-MYB transcription factor involved in the regulation of anthocyanin and flavonol accumulation in gerbera(Gerbera hybrida).GhMYB1a shares high sequence similarity with that of other characterized regulators of flavonol biosynthesis.In addition,GhMYB1a is also phylogenetically grouped with these proteins.The overexpression of GhMYB1a in gerbera and tobacco(Nicotiana tabacum)resulted in decreased anthocyanin accumulation and increased accumulation of flavonols by upregulating the structural genes involved in flavonol biosynthesis.We further found that GhMYB1a functions as a homodimer instead of interacting with basic helix-loop-helix cofactors.These results suggest that GhMYB1a is involved in regulating the anthocyanin and flavonol metabolic pathways through precise regulation of gene expression.The functional characterization of GhMYB1a provides insight into the biosynthesis and regulation of flavonols and anthocyanins.展开更多
Rheumatoid arthritis(RA)is a chronic inflammatory and destructive arthropathy with a high deformity rate.Despite numerous studies and clinical trials,no curative treatment is available for large weight-bearing joints....Rheumatoid arthritis(RA)is a chronic inflammatory and destructive arthropathy with a high deformity rate.Despite numerous studies and clinical trials,no curative treatment is available for large weight-bearing joints.Intra-articular(IA)injections could deliver high concentrations of drug to the afflicted joint and improve the drug efficacy while reducing systemic toxicity.However,free drugs are rapidly cleared from synovial fluid and do not significantly halt the progression of joint disease.Herein,a phospholipids-based controlledrelease gel was prepared for sustained IA delivery of celastrol(CEL)and the therapeutic efficiencywas evaluated in a rheumatoid arthritis rabbitmodel.The CEL-loaded gel(CEL-gel)contained up to 70%phospholipids yetwas easy to inject.After injecting into the joint cavity,CEL-gel achieved sol to gel phase transition without special stimuli and gelling agent.In vitro release and in vivo pharmacokinetic studies evidenced the stable and sustained release action of CEL-gel.A single IA injection of CEL-gel could maintain therapeutic efficiency for about 25 d and showed much better anti-arthritic efficacy compared to repeated injections of free drug solution(CEL-sol).Furthermore,the IA injection of CEL-gel greatly reduced the systemic toxicity of CEL.With good biocompatibility and biodegradability,CEL-gel might be a promising IA drug delivery system.展开更多
Incorporating antibacterial agent into biomimetic coating inspired by natural organisms with micronano structure surface has generated more interest for antifouling applications.In this work,poly(dimethylsiloxane)(PDM...Incorporating antibacterial agent into biomimetic coating inspired by natural organisms with micronano structure surface has generated more interest for antifouling applications.In this work,poly(dimethylsiloxane)(PDMS)-based triblock copolymers and sub-20 nm nanoparticles Ag and heterogeneous Fe_(3)O_(4)-coated Ag(Fe_(3)O_(4)@Ag)were used to construct microphase separation topography with oriented copolymer blocks structure.The artificial surface was verified by atomic force microscopy and scanning electron microscopy images.Meanwhile,the surface exhibited relative stable hydrophobic property,which was demonstrated by the water contact angle and dynamic air-bubble contact angle measurements.Consequently,after immersed in BSA solution 24 h and 720 h,the actual BSA absorption amount of the surface with Fe_(3)O_(4)@Ag nanoparticles was as low as 10%and 27%that of the initial BSA amount,respectively.Moreover,the surface also showed remarkable antibacterial performance,which effectively suppressed the growth rate of Escherichia coli.The strategy of constructing the flexible micro p hase separation structure by introducing heterogeneous inorganic antibacterial nanoparticles into a block copolymer substrate opens up a new way to create an antifouling surface coating.展开更多
Acute myocardial infarction (AMI) is rare in young adults. The management of these patients is considered as a clinical challenge. We report the case of a 26-year-old man who was presented to the Emergency Room of Aff...Acute myocardial infarction (AMI) is rare in young adults. The management of these patients is considered as a clinical challenge. We report the case of a 26-year-old man who was presented to the Emergency Room of Affiliated Hospital of Guilin Medical University with an acute onset of chest pain. Initially electrocardiogram (ECG) with no evidence of ST-segment abnormalities but QT prolongation a signal of sudden cardiac death, 20 minutes later, it revealed ST-segment elevation myocardial infarction (STEMI). Coronary angiography (CAG) demonstrated left main coronary artery occlusion. AMI was diagnosed based on clinical symptom, elevated cardiac biomarkers, electrocardiographic dynamic monitoring and CAG. The awareness of chest pain as possible underlying AMI symptom—especially in young patients presenting with QT prolongation—is crucial for clinical treatment, as a missed diagnosis can worsen the patient’s further prognosis. In addition, reperfusion arrhythmia is a challenge to short-term outcomes of young patients with AMI, so it is necessary to make preoperative risk stratification.展开更多
Typhoons in the western Pacific have a significant impact on the transport of heat,salt and particles through the Luzon Strait.However,there are very limited field observations of this impact because of extreme diffic...Typhoons in the western Pacific have a significant impact on the transport of heat,salt and particles through the Luzon Strait.However,there are very limited field observations of this impact because of extreme difficulties and even dangers for ship-based measurements during the rough weather.Here,we present the preliminary results from analyzing a dataset collected by a glider deployed west of the Luzon Strait a few days prior to the arrival of typhoon MITAG.The gilder data revealed an abnormally salinity(>34.8)subsurface water apparently sourced from Kuroshio intrusion during the typhoon.When typhoon MITAG traveled on the east of the Luzon Strait,the positive wind stress curl strengthened the cyclonic eddy and weakened the anti-cyclonic eddy.This led to a slowdown of Kuroshio and made its intrusion easier.The main axis of the Kuroshio at the northern part of the strait shifted westward after the typhoon and did not return to its original position until a week later.The Ekman transport from persistent northerly wind of typhoon MITAG was significant,but its importance in enhancing the Kuroshio intrusion is only secondary relative to the eddies variations.展开更多
Integrated computational materials engineering (ICME) is an emerging discipline that can speed up product development by unifying material, design, fabrication, and computational power in a virtual environment. Develo...Integrated computational materials engineering (ICME) is an emerging discipline that can speed up product development by unifying material, design, fabrication, and computational power in a virtual environment. Developing and adapting ICME in industries is a grand challenge technically and culturally. To help develop a strategy for development of this new technology area, an ICME approach was proposed and implemented in optimizing thin welded structure design. The key component in this approach is a database which includes material properties, static strength, impact strength, and failure parameters for a weld. The heat source models, microstructure model, and thermo-mechanical model involved in ICME for welding simulation were discussed. The shell elements representing method for a fusion weld were introduced in details for a butt joint, lap joint, and a Tee joint. Using one or multiple solid elements representing a spot weld in a shell model was also discussed. Database building methods for resistance spot welding and fusion welding have been developed.展开更多
All-dielectric metamaterials have emerged as a promising platform for low-loss and highly efficient terahertz devices. However, existing fabrication methods have difficulty in achieving a good balance between precisio...All-dielectric metamaterials have emerged as a promising platform for low-loss and highly efficient terahertz devices. However, existing fabrication methods have difficulty in achieving a good balance between precision and cost. Here, inspired by the nano-template-assisted self-assembly method, we develop a micro-templateassisted self-assembly(MTAS) method to prepare large-scale, high-precision, and flexible ceramic microsphere all-dielectric metamaterials with an area exceeding 900 cm × 900 cm. Free from organic solvents, vacuum, and complex equipment, the MTAS method ensures low-cost and environmentally friendly fabrication. The ceramic microsphere resonators can be readily assembled into nearly arbitrary arrangements and complex aggregates, such as dimers, trimers, quadrumers, and chains. Finally, using the heat-shrinkable substrate and dipole coupling effect, a broadband reflector with a bandwidth of 0.15 THz and a reflection of up to 95% is demonstrated.This work provides a versatile and powerful platform for terahertz all-dielectric metamaterials, with potential to be applied in a wide variety of high-efficiency terahertz devices.展开更多
This study proposed a tung-oil based magnetic targeted delivery microcapsules(MDTMs)to enhance the efficiency of self-healing coatings(SHC).Magnetic particles were used as function particles and emulsifier in synthesi...This study proposed a tung-oil based magnetic targeted delivery microcapsules(MDTMs)to enhance the efficiency of self-healing coatings(SHC).Magnetic particles were used as function particles and emulsifier in synthesis of microcapsules(MC).DSC,OM,SEM,TEM,VSM,NSS,EIS and SKP were used to characterize the compounds,structure,healing behavior and anti-corrosion performance.Results indicate that magnetically driven SHC(MD-SHC)reduces 50%migration path of the released tung oil,and increases the release rate of tung oil after the coating is mechanically damaged.SKP and EIS results suggest that the healing part has impressive anti-corrosion performance,scratches were filled with a large amount of tung oil in a short time,and the released tung oil had formed a complete oil film on scratches at 24 h with higher polarization resistance(R_(p)).R_(p)of MD-SHC(2.5×10^(5)–3.6×10^(5)Ωcm^(2))is 2.0–2.8 times of that the SHC(1.1×10^(5)–1.8×10^(5)Ωcm^(2)).The enrichment in MD-SHC at the interface decreases bonding strength from 7 to 4.5 MPa as the mass additive of microcapsules reaches 15 wt.%.The current work proves the effectiveness of MD-SHC in improving self-healing ability.展开更多
In this paper,we present a categorical version of the first and second fundamental theorems of the invariant theory for the quantized symplectic groups.Our methods depend on the theory of braided strict monoidal categ...In this paper,we present a categorical version of the first and second fundamental theorems of the invariant theory for the quantized symplectic groups.Our methods depend on the theory of braided strict monoidal categories which are pivotal,more explicitly,the diagram category of framed tangles.展开更多
We investigated the effects of oxygen vacancies on the structural, magnetic, and transport properties of Lal-xSrxMnO3 （x=0.1, 0.2, 0.33, 0.4, and 0.5） grown around a critical point （without/with oxygen vacancies） ...We investigated the effects of oxygen vacancies on the structural, magnetic, and transport properties of Lal-xSrxMnO3 （x=0.1, 0.2, 0.33, 0.4, and 0.5） grown around a critical point （without/with oxygen vacancies） under low oxygen pressure （10 Pa） and high oxygen pressure （40 Pa）. We found that all films exhibit ferromagnetic behavior below the magnetic critical temperature, and that the films grown under low oxygen pressures have degraded magnetic properties with lower Curie temperatures and smaller magnetic moments. These results show that in epitaxial La1-xSrxMnO3 thin films, the magnetic and transport properties are very sensitive to doping concentration and oxygen vacancies. Phase diagrams of the films based on the doping concentration and oxygen vacancies were plotted and discussed.展开更多
To the Editor:Lateral epicondylalgia,whose incidence rate is approximately 1.3%,not only occurs in tennis players(tennis players only account for 5%^([1])),but is also related to smoking,poor social support,and heavy ...To the Editor:Lateral epicondylalgia,whose incidence rate is approximately 1.3%,not only occurs in tennis players(tennis players only account for 5%^([1])),but is also related to smoking,poor social support,and heavy physical labor.Surgical treatment should be considered when conservative treatment fails after 6 months,which occurs in 10%of lateral epicondylalgia cases.展开更多
Background:Neuroimaging-based connectome studies have indicated that major depressive disorder(MDD)is associated with dis-rupted topological organization of large-scale brain networks.However,the disruptions and their...Background:Neuroimaging-based connectome studies have indicated that major depressive disorder(MDD)is associated with dis-rupted topological organization of large-scale brain networks.However,the disruptions and their clinical and cognitive relevance are not well established for morphological brain networks in adolescent MDD.Objective:To investigate the topological alterations of single-subject morphological brain networks in adolescent MDD.Methods:Twenty-five first-episode,treatment-naive adolescents with MDD and 19 healthy controls(HCs)underwent T1-weighted magnetic resonance imaging and a battery of neuropsychological tests.Single-subject morphological brain networks were constructed separately based on cortical thickness,fractal dimension,gyrification index,and sulcus depth,and topologically characterized by graph-based approaches.Between-group differences were inferred by permutation testing.For significant alterations,partial correla-tions were used to examine their associations with clinical and neuropsychological variables in the patients.Finally,a support vector machine was used to classify the patients from controls.Results:Compared with the HCs,the patients exhibited topological alterations only in cortical thickness-based networks character-ized by higher nodal centralities in parietal(left primary sensory cortex)but lower nodal centralities in temporal(left parabelt complex,right perirhinal ectorhinal cortex,right area PHT and right ventral visual complex)regions.Moreover,decreased nodal centralities of some temporal regions were correlated with cognitive dysfunction and clinical characteristics of the patients.These results were largely reproducible for binary and weighted network analyses.Finally,topological properties of the cortical thickness-based net-works were able to distinguish the MDD adolescents from HCs with 87.6%accuracy.Conclusion:Adolescent MDD is associated with disrupted topological organization of morphological brain networks,and the disrup-tions provide potential biomarkers for diagnosing and monitoring the disease.展开更多
基金Financial support from Beijing Natural Science Foundation(No.7232283)。
文摘From the seeds of Peganum harmala L.,three new alkaloids ofβ-carboline were isolated.Among them,peganumiums A(1)and B(2)were dimers with specific new scaffolds,all with long conjugated systems.Peganumium A and peganumium C(3)were ionic alkaloid salts and peganumium B was a hexacycliccondensed alkaloid.The biosynthetic pathways of the three compounds above were also speculated.A preliminary cytotoxicity assay revealed that peganumium B had strong in vitro antiproliferative ability against a variety of cancer cells.The analysis of^(1)H nuclear magnetic resonance(NMR)metabolomics suggested that the antiproliferative mechanism of peganumium B could be associated with the biosynthesis of phenylalanine,tyrosine and tryptophan,the metabolism of glycine,serine,and threonine,the metabolism of taurine and hypotaurine,and the metabolism of nicotinate and nicotinamide.In addition,peganumium B could reduce the mitochondrial content of body-wall muscle cells of a Caenorhabditis elegans(C.elegans)strain in vivo.
基金Zhejiang Medical and Health Technology Project(Project No.2020PY072)。
文摘Objective:To explore a simple method for improving the diagnostic accuracy of malignant lung nodules based on imaging features of lung nodules.Methods:A retrospective analysis was conducted on the imaging data of 114 patients who underwent lung nodule surgery in the Thoracic Surgery Department of the First People’s Hospital of Huzhou from June to September 2024.Imaging features of lung nodules were summarized and trained using a BP neural network.Results:Training with the BP neural network increased the diagnostic accuracy for distinguishing between benign and malignant lung nodules based on imaging features from 84.2%(manual assessment)to 94.1%.Conclusion:Training with the BP neural network significantly improves the diagnostic accuracy of lung nodule malignancy based solely on imaging features.
基金supported by the National Key R&D Program of China(2020YFA07106003)the National Natural Science Foundation of China(42061073)the Innovation Team of Sichuan Earthquake Agency(202401).
文摘We conducted a rapid seismic intensity assessment of a M 6.8 earthquake in Dingri,Xizang,using a ground motion parameter attenuation model based on the shortest fault distance combined with either an empirical equation for the surface rupture length or data on the aftershocks that occurred within 1.5 hr after the earthquake.The assessment showed that the empirical equation for the relationship between the surface rupture length and magnitude established by Wells et al.yielded a surface rupture length that was closer to the actual value,while the seismic intensity determined using a combination of the ground motion parameter attenuation model and the empirical equation for the surface rupture length was relatively in line with the intensity from the actual investigation.This study also demonstrated that manual intervention and screening are needed for aftershocks within 1.5 hr after the earthquake if this information is to be employed in the intensity assessment.In addition,if the death assessment model does not consider the seismic vulnerability of local buildings,significant errors can occur in practice.Nevertheless,the disaster assessment results were obtained within 5 min after the earthquake,thus providing important data support for the government emergency command and decision-making associated with the emergency rescue response.
基金supported by the Foundation of Guangzhou Science and Technology Project(201904010127 to C.Z.)National Natural Science Foundation of China(Grants 31372099,31601784,and 31672188 to X.W.,L.L.and Y.W.,respectively)+1 种基金Open Project Foundation of South China Normal University(2018KF0202 to C.Z.)Specialized Research Fund for Graduate Students at South China Normal University(2014ssxm26).
文摘Anthocyanins and flavonols have vital roles in flower coloration,plant development,and defense.Because anthocyanins and flavonols share the same subcellular localization and common biosynthetic substrates,these pathways may compete for substrates.However,the mechanism regulating this potential competition remains unclear.Here,we identified GhMYB1a,an R2R3-MYB transcription factor involved in the regulation of anthocyanin and flavonol accumulation in gerbera(Gerbera hybrida).GhMYB1a shares high sequence similarity with that of other characterized regulators of flavonol biosynthesis.In addition,GhMYB1a is also phylogenetically grouped with these proteins.The overexpression of GhMYB1a in gerbera and tobacco(Nicotiana tabacum)resulted in decreased anthocyanin accumulation and increased accumulation of flavonols by upregulating the structural genes involved in flavonol biosynthesis.We further found that GhMYB1a functions as a homodimer instead of interacting with basic helix-loop-helix cofactors.These results suggest that GhMYB1a is involved in regulating the anthocyanin and flavonol metabolic pathways through precise regulation of gene expression.The functional characterization of GhMYB1a provides insight into the biosynthesis and regulation of flavonols and anthocyanins.
基金financially supported by the National Natural Science Foundation of China (Nos. 82173758, China)Sichuan major science and technology project on biotechnology and medicine (2018SZDZX0018, China)
文摘Rheumatoid arthritis(RA)is a chronic inflammatory and destructive arthropathy with a high deformity rate.Despite numerous studies and clinical trials,no curative treatment is available for large weight-bearing joints.Intra-articular(IA)injections could deliver high concentrations of drug to the afflicted joint and improve the drug efficacy while reducing systemic toxicity.However,free drugs are rapidly cleared from synovial fluid and do not significantly halt the progression of joint disease.Herein,a phospholipids-based controlledrelease gel was prepared for sustained IA delivery of celastrol(CEL)and the therapeutic efficiencywas evaluated in a rheumatoid arthritis rabbitmodel.The CEL-loaded gel(CEL-gel)contained up to 70%phospholipids yetwas easy to inject.After injecting into the joint cavity,CEL-gel achieved sol to gel phase transition without special stimuli and gelling agent.In vitro release and in vivo pharmacokinetic studies evidenced the stable and sustained release action of CEL-gel.A single IA injection of CEL-gel could maintain therapeutic efficiency for about 25 d and showed much better anti-arthritic efficacy compared to repeated injections of free drug solution(CEL-sol).Furthermore,the IA injection of CEL-gel greatly reduced the systemic toxicity of CEL.With good biocompatibility and biodegradability,CEL-gel might be a promising IA drug delivery system.
基金financially supported by the National Natural Science Foundation of China(Nos.51706166 and 51773163)the Joint Funds of the Equipment Pre-Research of Ministry of Education of China(No.6141A02022225)+1 种基金Sanya Science and Education Innovation Park of Wuhan University of Technology(2020KF0025)the Fundamental Research Funds for the Central Universities(WUT:2020III038GX)。
文摘Incorporating antibacterial agent into biomimetic coating inspired by natural organisms with micronano structure surface has generated more interest for antifouling applications.In this work,poly(dimethylsiloxane)(PDMS)-based triblock copolymers and sub-20 nm nanoparticles Ag and heterogeneous Fe_(3)O_(4)-coated Ag(Fe_(3)O_(4)@Ag)were used to construct microphase separation topography with oriented copolymer blocks structure.The artificial surface was verified by atomic force microscopy and scanning electron microscopy images.Meanwhile,the surface exhibited relative stable hydrophobic property,which was demonstrated by the water contact angle and dynamic air-bubble contact angle measurements.Consequently,after immersed in BSA solution 24 h and 720 h,the actual BSA absorption amount of the surface with Fe_(3)O_(4)@Ag nanoparticles was as low as 10%and 27%that of the initial BSA amount,respectively.Moreover,the surface also showed remarkable antibacterial performance,which effectively suppressed the growth rate of Escherichia coli.The strategy of constructing the flexible micro p hase separation structure by introducing heterogeneous inorganic antibacterial nanoparticles into a block copolymer substrate opens up a new way to create an antifouling surface coating.
文摘Acute myocardial infarction (AMI) is rare in young adults. The management of these patients is considered as a clinical challenge. We report the case of a 26-year-old man who was presented to the Emergency Room of Affiliated Hospital of Guilin Medical University with an acute onset of chest pain. Initially electrocardiogram (ECG) with no evidence of ST-segment abnormalities but QT prolongation a signal of sudden cardiac death, 20 minutes later, it revealed ST-segment elevation myocardial infarction (STEMI). Coronary angiography (CAG) demonstrated left main coronary artery occlusion. AMI was diagnosed based on clinical symptom, elevated cardiac biomarkers, electrocardiographic dynamic monitoring and CAG. The awareness of chest pain as possible underlying AMI symptom—especially in young patients presenting with QT prolongation—is crucial for clinical treatment, as a missed diagnosis can worsen the patient’s further prognosis. In addition, reperfusion arrhythmia is a challenge to short-term outcomes of young patients with AMI, so it is necessary to make preoperative risk stratification.
基金The fund from Science,Technology and Innovation Commission of Shenzhen Municipality under contract No.JCYJ20210324105211031the National Natural Science Foundation of China under contract No.41720104001.
文摘Typhoons in the western Pacific have a significant impact on the transport of heat,salt and particles through the Luzon Strait.However,there are very limited field observations of this impact because of extreme difficulties and even dangers for ship-based measurements during the rough weather.Here,we present the preliminary results from analyzing a dataset collected by a glider deployed west of the Luzon Strait a few days prior to the arrival of typhoon MITAG.The gilder data revealed an abnormally salinity(>34.8)subsurface water apparently sourced from Kuroshio intrusion during the typhoon.When typhoon MITAG traveled on the east of the Luzon Strait,the positive wind stress curl strengthened the cyclonic eddy and weakened the anti-cyclonic eddy.This led to a slowdown of Kuroshio and made its intrusion easier.The main axis of the Kuroshio at the northern part of the strait shifted westward after the typhoon and did not return to its original position until a week later.The Ekman transport from persistent northerly wind of typhoon MITAG was significant,but its importance in enhancing the Kuroshio intrusion is only secondary relative to the eddies variations.
文摘Integrated computational materials engineering (ICME) is an emerging discipline that can speed up product development by unifying material, design, fabrication, and computational power in a virtual environment. Developing and adapting ICME in industries is a grand challenge technically and culturally. To help develop a strategy for development of this new technology area, an ICME approach was proposed and implemented in optimizing thin welded structure design. The key component in this approach is a database which includes material properties, static strength, impact strength, and failure parameters for a weld. The heat source models, microstructure model, and thermo-mechanical model involved in ICME for welding simulation were discussed. The shell elements representing method for a fusion weld were introduced in details for a butt joint, lap joint, and a Tee joint. Using one or multiple solid elements representing a spot weld in a shell model was also discussed. Database building methods for resistance spot welding and fusion welding have been developed.
基金National Natural Science Foundation of China(NSFC)(61774020,51502179)Department of Education of Hebei Province(QN2016156)+3 种基金Natural Science Foundation of Hebei Province(E2017210096)Fund of IPOC Beijing University of Posts and Telecommunications(BUPT)(IPOC2017ZT06)Fundamental Research Funds for the Central Universities(2018XKJC05)General Financial Grant from the China Postdoctoral Science Foundation(2017M620693)
文摘All-dielectric metamaterials have emerged as a promising platform for low-loss and highly efficient terahertz devices. However, existing fabrication methods have difficulty in achieving a good balance between precision and cost. Here, inspired by the nano-template-assisted self-assembly method, we develop a micro-templateassisted self-assembly(MTAS) method to prepare large-scale, high-precision, and flexible ceramic microsphere all-dielectric metamaterials with an area exceeding 900 cm × 900 cm. Free from organic solvents, vacuum, and complex equipment, the MTAS method ensures low-cost and environmentally friendly fabrication. The ceramic microsphere resonators can be readily assembled into nearly arbitrary arrangements and complex aggregates, such as dimers, trimers, quadrumers, and chains. Finally, using the heat-shrinkable substrate and dipole coupling effect, a broadband reflector with a bandwidth of 0.15 THz and a reflection of up to 95% is demonstrated.This work provides a versatile and powerful platform for terahertz all-dielectric metamaterials, with potential to be applied in a wide variety of high-efficiency terahertz devices.
文摘This study proposed a tung-oil based magnetic targeted delivery microcapsules(MDTMs)to enhance the efficiency of self-healing coatings(SHC).Magnetic particles were used as function particles and emulsifier in synthesis of microcapsules(MC).DSC,OM,SEM,TEM,VSM,NSS,EIS and SKP were used to characterize the compounds,structure,healing behavior and anti-corrosion performance.Results indicate that magnetically driven SHC(MD-SHC)reduces 50%migration path of the released tung oil,and increases the release rate of tung oil after the coating is mechanically damaged.SKP and EIS results suggest that the healing part has impressive anti-corrosion performance,scratches were filled with a large amount of tung oil in a short time,and the released tung oil had formed a complete oil film on scratches at 24 h with higher polarization resistance(R_(p)).R_(p)of MD-SHC(2.5×10^(5)–3.6×10^(5)Ωcm^(2))is 2.0–2.8 times of that the SHC(1.1×10^(5)–1.8×10^(5)Ωcm^(2)).The enrichment in MD-SHC at the interface decreases bonding strength from 7 to 4.5 MPa as the mass additive of microcapsules reaches 15 wt.%.The current work proves the effectiveness of MD-SHC in improving self-healing ability.
基金supported by National Natural Science Foundation of China(Grant No.11301195)China Scholarship Council and a research foundation of Huaqiao University(Grant No.2014KJTD14)。
文摘In this paper,we present a categorical version of the first and second fundamental theorems of the invariant theory for the quantized symplectic groups.Our methods depend on the theory of braided strict monoidal categories which are pivotal,more explicitly,the diagram category of framed tangles.
基金supported by the National Key Basic Research Program of China(Grant Nos.2014CB921001,and 2013CB328706)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(GrantNo.QYZDJ-SSW-SLH020)+1 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(GrantNo.XDB07030200)the National Natural Science Foundation of China(Grant Nos.11574365,11474349,11674385,and 11404380)
文摘We investigated the effects of oxygen vacancies on the structural, magnetic, and transport properties of Lal-xSrxMnO3 （x=0.1, 0.2, 0.33, 0.4, and 0.5） grown around a critical point （without/with oxygen vacancies） under low oxygen pressure （10 Pa） and high oxygen pressure （40 Pa）. We found that all films exhibit ferromagnetic behavior below the magnetic critical temperature, and that the films grown under low oxygen pressures have degraded magnetic properties with lower Curie temperatures and smaller magnetic moments. These results show that in epitaxial La1-xSrxMnO3 thin films, the magnetic and transport properties are very sensitive to doping concentration and oxygen vacancies. Phase diagrams of the films based on the doping concentration and oxygen vacancies were plotted and discussed.
基金National Key Research and Development Program of China(No. 2019YFF0302305)
文摘To the Editor:Lateral epicondylalgia,whose incidence rate is approximately 1.3%,not only occurs in tennis players(tennis players only account for 5%^([1])),but is also related to smoking,poor social support,and heavy physical labor.Surgical treatment should be considered when conservative treatment fails after 6 months,which occurs in 10%of lateral epicondylalgia cases.
基金supported by the Key-Area Research and Development Program of Guangdong Province (No.2019B030335001)National Natural Science Foundation of China (Nos.81922036)+1 种基金Key Realm R&D Program of Guangzhou (No.202007030005)Natural Science Foundation of Guangdong Province (2021A1515010746).
文摘Background:Neuroimaging-based connectome studies have indicated that major depressive disorder(MDD)is associated with dis-rupted topological organization of large-scale brain networks.However,the disruptions and their clinical and cognitive relevance are not well established for morphological brain networks in adolescent MDD.Objective:To investigate the topological alterations of single-subject morphological brain networks in adolescent MDD.Methods:Twenty-five first-episode,treatment-naive adolescents with MDD and 19 healthy controls(HCs)underwent T1-weighted magnetic resonance imaging and a battery of neuropsychological tests.Single-subject morphological brain networks were constructed separately based on cortical thickness,fractal dimension,gyrification index,and sulcus depth,and topologically characterized by graph-based approaches.Between-group differences were inferred by permutation testing.For significant alterations,partial correla-tions were used to examine their associations with clinical and neuropsychological variables in the patients.Finally,a support vector machine was used to classify the patients from controls.Results:Compared with the HCs,the patients exhibited topological alterations only in cortical thickness-based networks character-ized by higher nodal centralities in parietal(left primary sensory cortex)but lower nodal centralities in temporal(left parabelt complex,right perirhinal ectorhinal cortex,right area PHT and right ventral visual complex)regions.Moreover,decreased nodal centralities of some temporal regions were correlated with cognitive dysfunction and clinical characteristics of the patients.These results were largely reproducible for binary and weighted network analyses.Finally,topological properties of the cortical thickness-based net-works were able to distinguish the MDD adolescents from HCs with 87.6%accuracy.Conclusion:Adolescent MDD is associated with disrupted topological organization of morphological brain networks,and the disrup-tions provide potential biomarkers for diagnosing and monitoring the disease.
