Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by...Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by a certain degree in the 2D plane.Such 2D functional materials are realized by stacking the exfoliated wurtzite(wz)monolayers with“self-healable”nature,which host strongly coupled ferroelasticity/antiferroelectricity and benign stability.The AFE candidates,i.e.,Zn X and Cd X(X=S,Se,Te),are all semiconductors with direct bandgap atΓpoint,which harbors switchable antiferroelectricity and ferroelasticity with low transition barriers,hidden spin polarization,as well as giant in-plane negative Poisson's ratio(NPR),enabling the co-tunability of hidden spin characteristics and auxetic magnitudes via AFE switching.The 2D AFE wz crystals provide a platform to probe the interplay of 2D antiferroelectricity,ferroelasticity,NPR,and spin effects,shedding new light on the rich physics and device design in wz semiconductors.展开更多
Among several dark matter candidates,bosonic ultra-light(sub-meV)dark matter is well motivated because it could couple to the Standard Model and induce new forces.Previous MICROSCOPE and E¨ot–Wash torsion experi...Among several dark matter candidates,bosonic ultra-light(sub-meV)dark matter is well motivated because it could couple to the Standard Model and induce new forces.Previous MICROSCOPE and E¨ot–Wash torsion experiments have achieved high accuracy in the sub-1 Hz region.However,at higher frequencies there is still a lack of relevant experimental research.We propose an experimental scheme based on the diamagnetic levitated micromechanical oscillator,one of the most sensitive sensors for acceleration sensitivity below the kilohertz scale.In order to improve the measurement range,we utilize a sensor whose resonance frequencyω0 could be adjusted from 0.1 Hz to 100 Hz.The limits of the coupling constant gB-Lare improved by more than 10 times compared to previous reports,and it may be possible to achieve higher accuracy by using the array of sensors in the future.展开更多
This study aims to analyze the clinical use of ornidazole injection at the post-marketing stage by centralized hospital monitoring system method,and investigate its widespread use in patients,in order to regulate and ...This study aims to analyze the clinical use of ornidazole injection at the post-marketing stage by centralized hospital monitoring system method,and investigate its widespread use in patients,in order to regulate and guide the rational drug use,improve the drug specificity and provide a basis for drug therapy.The study adopts a prospective,multi-center,large sample size,centralized hospital monitoring system.We selected five leading hospitals in Hubei province,and observed the inpatients who received the ornidazole injection from July 1,2015 to October 31,2015.The basic information of patients was recorded,as well as the drug use and adverse events.The statistical analysis was performed based on these data.A total of 4396 individuals were enrolled in this study,most of them were middle-aged female patients and the ornidazole injection was mainly used as prophylactic prior to surgery to prevent the infections,and surgical treatment of anaerobic infections,abdominal infections and pelvic infections.The irrational drug use existed mainly in the prescribing and administration process,including unreasonable dosing frequency,rapid intravenous drip speed and extended duration of drug use.Eleven cases of adverse reactions were collected during the monitoring,incidence rate of adverse reactions was 2.5‰;adverse drug reactions occurred within 30 min.The study results fully reflected the usage of ornidazole injection in the real world.Based on the study,we calculated the adverse reaction incidence of ornidazole and identified the risk factors which may affect the safety of ornidazole injection.Study results strongly recommend that the manufacturers should publish standards for inpatient use and doctors should prescribe with caution accordingly.展开更多
This paper aims to investigate if the dental restoration of nickel-chromium based alloy(Ni-Cr) leads to the enhanced excretions of Ni and Cr in urine.Seven hundred and ninety-five patients in a dental hospital had sin...This paper aims to investigate if the dental restoration of nickel-chromium based alloy(Ni-Cr) leads to the enhanced excretions of Ni and Cr in urine.Seven hundred and ninety-five patients in a dental hospital had single or multiple Ni-Cr alloy restoration recently and 198 controls were recruited to collect information on dental restoration by questionnaire and clinical examination.Urinary concentrations of Ni and Cr from each subject were measure by graphite furnace atomic absorption spectrometry.Compared to the control group,the urinary level of Ni was significantly higher in the patient group of < 1 month of the restoration duration,among which higher Ni excretions were found in those with either a higher number of teeth replaced by dental alloys or a higher index of metal crown not covered with the porcelain.Urinary levels of Cr were significantly higher in the three patient groups of <1,1 to <3 and 3 to <6 months,especially in those with a higher metal crown exposure index.Linear curve estimations showed better relationships between urinary Ni and Cr in patients within 6-month groups.Our data suggested significant increased excretions of urinary Ni and Cr after dental restoration.Potential short- and long-term effects of Ni-Cr alloy restoration need to be investigated.展开更多
Fluidics is one of the most historic subjects that are well-established over centuries on the macroscopic scale.In recent years,fluid detection using a number of micro/nano scale devices has been achieved.However,the ...Fluidics is one of the most historic subjects that are well-established over centuries on the macroscopic scale.In recent years,fluid detection using a number of micro/nano scale devices has been achieved.However,the interaction of microfluid and solid devices on micro/nano-meter scale still lacks in-depth research.We demonstrate a practical nanomechanical detector for microfluidics via a string resonator with high Q-factor,suspended over a hole.This device is placed under a jet nozzle with several microns of diameter,and the interaction between the micro-gas flow and the resonator is observed by monitoring the variation of the fundamental frequency and the quality factor.Moreover,we manage to measure the fluctuations of the micro-gas flow on the nanomechanical resonator by means of stochastic resonance.This work manifests a potential platform for detecting dynamical fluid behaviors at microscopic scale for novel fluid physics.展开更多
We realize a coherent transfer of mechanical excitation in a finely controlled artificial nanomechanical lattice.We also realize strong dynamic coupling between adjacent high-Q mechanical resonators,via modulated diel...We realize a coherent transfer of mechanical excitation in a finely controlled artificial nanomechanical lattice.We also realize strong dynamic coupling between adjacent high-Q mechanical resonators,via modulated dielectric force at the frequency difference between them.An excitation transfer across a lattice consisting of 7 nanobeams is observed by applying a design sequence of switching for couplings,with the final effective population reaching 0.94.This work not only demonstrates the ability to fully control an artificial lattice but also provides an efficient platform for studying complicated dynamics in one-dimensional systems.展开更多
Physical systems with gain and loss can be described by a non-Hermitian Hamiltonian,which is degenerated at the exceptional points(EPs).Many new and unexpected features have been explored in the non-Hermitian systems ...Physical systems with gain and loss can be described by a non-Hermitian Hamiltonian,which is degenerated at the exceptional points(EPs).Many new and unexpected features have been explored in the non-Hermitian systems with a great deal of recent interest.One of the most fascinating features is that chiral state conversion appears when one EP is encircled dynamically.Here,we propose an easy-controllable levitated microparticle system that carries a pair of EPs and realize slow evolution of the Hamiltonian along loops in the parameter plane.Utilizing the controllable rotation angle,gain and loss coefficients,we can control the structure,size and location of the loops in situ.We demonstrate that,under the joint action of topological structure of energy surfaces and nonadiabatic transitions,the chiral behavior emerges both along a loop encircling an EP and even along a straight path away from the EP.This work broadens the range of parameter space for the chiral state conversion,and proposes a useful platform to explore the interesting properties of exceptional points physics.展开更多
Image inpainting based on deep learning has been greatly improved.The original purpose of image inpainting was to repair some broken photos, suchas inpainting artifacts. However, it may also be used for malicious oper...Image inpainting based on deep learning has been greatly improved.The original purpose of image inpainting was to repair some broken photos, suchas inpainting artifacts. However, it may also be used for malicious operations,such as destroying evidence. Therefore, detection and localization of imageinpainting operations are essential. Recent research shows that high-pass filteringfull convolutional network (HPFCN) is applied to image inpainting detection andachieves good results. However, those methods did not consider the spatial location and channel information of the feature map. To solve these shortcomings, weintroduce the squeezed excitation blocks (SE) and propose a high-pass filter attention full convolutional network (HPACN). In feature extraction, we apply concurrent spatial and channel attention (scSE) to enhance feature extraction and obtainmore information. Channel attention (cSE) is introduced in upsampling toenhance detection and localization. The experimental results show that the proposed method can achieve improvement on ImageNet.展开更多
Objective： Throughout the world, fetal growth restriction（FGR） is one of the most severe complications occurring during pregnancy. It is subsequently associated with neurologic abnormalities in chldren. Our aim was...Objective： Throughout the world, fetal growth restriction（FGR） is one of the most severe complications occurring during pregnancy. It is subsequently associated with neurologic abnormalities in chldren. Our aim was to investigate the spatial learning and memory ability of rat offspring born With FGR. Methods：A rat model of FGR was constructed using the method of passive smoking. Spatial learning and memory were studied in rat offspring born with FGR by assessing the animals＇ performance using the Morris water maze task. Results： At 1- and 2- months of age, both female and male offspring rats showed impairment of performance, while at 4 months of age, only female rats showed impaired performance. The FGR offspring spent a longer time swimming and used inefficient strategies（P〈 0.05, respectively）. However, there were no significant maze performance FGR effects in the 4 month old male rats. In all groups of FGR offspring, irrespective of age or sex, the time spent in the platform quadrant by the rat was significantly less than that in the control group（P〈 0.05）. Conclusion： The Morris water maze performance decreased in rat offspring born with FGR. It is suggested that FGR can cause impairments of spatial learning and memory in young animals.展开更多
The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in fossils.It records the crucial processes of continuous subduction and reduction of t...The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in fossils.It records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern hemisphere.Thus,it is of great significance for explaining the global paleogeographic evolution,tectonic activities and biodiversity changes during this critical period.The blocks on both sides of the southern Tienshan suture zone and the Longmu Co-ShuanghuChangning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions,showing important tectonic paleogeographic partitioning significance.The two suture zones represent the main branches of the PaleoAsian Ocean and the Paleo-Tethys Ocean,respectively,and on this basis the Devonian System can be subdivided into three types:the Tienshan type,the Tethys type and the Gondwana type.Based on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas,this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction,providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of Gondwana.The results indicate that the North Qiangtang,South Qiangtang,Simao,Baoshan and Tengchong terranes,as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block,while the Lhasa Terrane has affinities with the Australian Block,and may be located between the South China and Australian blocks.In the Emsian(Early Devonian),the South China Block separated from the northern margin of Gondwana,a process that was accompanied by the opening of the Jinshajiang-Ailaoshan Ocean.In the Middle Devonian,the mid-oceanic ridge of the Paleo-Tethys Ocean expanded rapidly,corresponding with a global sea-level rise,the widespread development of carbonate platforms and nadir values of Devonian seawater strontium isotopes.By the Late Devonian,the Paleo-Tethys Ocean had reached a considerable size,leading to abundant occurrences of Upper Devonian radiolarian cherts in the Paleo-Tethys suture zones.展开更多
Marginal Fisher analysis （MFA） is a repre- sentative margin-based learning algorithm for face recognition. A major problem in MFA is how to select appropriate parameters, k1 and k2, to construct the respective intri...Marginal Fisher analysis （MFA） is a repre- sentative margin-based learning algorithm for face recognition. A major problem in MFA is how to select appropriate parameters, k1 and k2, to construct the respective intrinsic and penalty graphs. In this paper, we propose a novel method called nearest-neighbor （NN） classifier motivated marginal discriminant projections （NN-MDP）. Motivated by the NN classifier, NN-MDP seeks a few projection vectors to prevent data samples from being wrongly categorized. Like MFA, NN-MDP can characterize the compactness and separability of samples simultaneously. Moreover, in contrast to MFA, NN-MDP can actively construct the intrinsic graph and penalty graph without unknown parameters. Experimental results on the 0RL, Yale, and FERET face databases show that NN-MDP not only avoids the intractability, and high expense of neighborhood parameter selection, but is also more applicable to face recognition with NN classifier than other methods.展开更多
Open quantum systems are always exposed to an external environment,which result in interacting and exchanging information between quantum systems and their surroundings.The dynamics of real open quantum systems are of...Open quantum systems are always exposed to an external environment,which result in interacting and exchanging information between quantum systems and their surroundings.The dynamics of real open quantum systems are often expected to deviate from the idealized Markovian process of losing information to their surrounding environment and to exhibit non-Markovian展开更多
Laryngeal squamous cell carcinoma(LSCC)is the most common type of head and neck squamous cell carcinoma(HNSCC)worldwide.Protein phosphatase 2A(PP2A)dysfunction has been widely reported in a broad range of malignancies...Laryngeal squamous cell carcinoma(LSCC)is the most common type of head and neck squamous cell carcinoma(HNSCC)worldwide.Protein phosphatase 2A(PP2A)dysfunction has been widely reported in a broad range of malignancies due to its distinctive role in miscellaneous cellular processes.However,it is poorly understood whether aberrant alterations of PP2A are involved in the network of oncogenic events in LSCC.Here,we detected a panel of PP2A-associated proteins using western blot in both laryngeal squamous cell carcinoma tissues and paired adjacent normal tissues from patients(Data S1).We found that phospho-PP2A/C(Y307),α4,cancerous inhibitor of protein phosphatase 2A(CIP2A),Akt,ezrin,phospho-ezrin(T567),14-3-3,and focal adhesion kinase(FAK)showed increased expression levels in carcinoma tissues relative to normal tissues,while phospho-Akt(T308)showed decreased levels.Our study,thus,provides a rationale for targeting PP2A to develop novel therapies and proposes a combination of interrelated biomarkers for the diagnostic evaluation and prognosis prediction in LSCC.展开更多
Monolayers of layered materials,such as graphite and molybdenum dichalcogenides,have been the focus of materials science in the last decades.Here,we reveal benign stability and intriguing physical properties in the th...Monolayers of layered materials,such as graphite and molybdenum dichalcogenides,have been the focus of materials science in the last decades.Here,we reveal benign stability and intriguing physical properties in the thinnest monolayer wurtzite(wz)semiconductors,which can be exfoliated from their bulk and stacked to reform the wz crystals.The candidate ZnX and CdX(X=S,Se,Te)monolayers possess low cleavage energy and direct bandgaps,which harbor strongly coupled ferroelectricity and ferroelasticity with low transition barriers,giant in-plane negative Poisson’s ratio,as well as giant Rashba spin splitting,enabling the co-tunability of spin splitting and auxetic magnitudes via multiferroic switching.These wz monolayers can be used as building blocks of devices structures,due to their inherent“self-healable”capacity,which offer more flexibility for semiconductor fabrication and provide a natural platform to probe the interplay of multiple physical effects,bringing light into the rich physics in tetrahedral semiconductors.展开更多
The present paper is concerned with stability and L_(2) gain analysis of switched distributed parameter system(SDPS)with time delay.First,exponential stability is discussed,and the state decay estimate of the system i...The present paper is concerned with stability and L_(2) gain analysis of switched distributed parameter system(SDPS)with time delay.First,exponential stability is discussed,and the state decay estimate of the system is explicitly given by using linear matrix inequalities(LMIs)incorporating with the average dwell time(ADT)method.Second,L_(2) gain analysis is also studied.At last,illustrative examples are given to show the effectiveness of the proposed method.The main contribution of the paper is:some criteria of exponential stability and L_(2) gain for multiple-input multiple-output(MIMO)switched PDE are developed in the form of LMIs and ADT signal for the first time.The advantage of the work is we generalize the application range of the related research.The proposed method is expected to provide an effective tool for stability and H∞control analysis of SDPS.展开更多
基金supported by Natural Science Foundation of Guangdong Province,China (Grant Nos.2022A1515011990 and 2023A1515030086)National Natural Science Foundation of China (Grant Nos.11774239,11804230 and 61827815)+2 种基金National Key R&D Program of China (Grant No.2019YFB2204500)Shenzhen Science and Technology Innovation Commission (Grant Nos.JCYJ20220531102601004,KQTD20180412181422399 and JCYJ20180507181858539)High-Level University Construction Funds of SZU (Grant Nos.860-000002081209 and 860-000002110711)。
文摘Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by a certain degree in the 2D plane.Such 2D functional materials are realized by stacking the exfoliated wurtzite(wz)monolayers with“self-healable”nature,which host strongly coupled ferroelasticity/antiferroelectricity and benign stability.The AFE candidates,i.e.,Zn X and Cd X(X=S,Se,Te),are all semiconductors with direct bandgap atΓpoint,which harbors switchable antiferroelectricity and ferroelasticity with low transition barriers,hidden spin polarization,as well as giant in-plane negative Poisson's ratio(NPR),enabling the co-tunability of hidden spin characteristics and auxetic magnitudes via AFE switching.The 2D AFE wz crystals provide a platform to probe the interplay of 2D antiferroelectricity,ferroelasticity,NPR,and spin effects,shedding new light on the rich physics and device design in wz semiconductors.
基金the National Natural Science Foundation of China(Grant Nos.12205291,12075115,12075116,11890702,and 12150011)the Fundamental Research Funds for the Central UniversitiesAnhui Provincial Natural Science Foundation(Grant No.2208085QA16)。
文摘Among several dark matter candidates,bosonic ultra-light(sub-meV)dark matter is well motivated because it could couple to the Standard Model and induce new forces.Previous MICROSCOPE and E¨ot–Wash torsion experiments have achieved high accuracy in the sub-1 Hz region.However,at higher frequencies there is still a lack of relevant experimental research.We propose an experimental scheme based on the diamagnetic levitated micromechanical oscillator,one of the most sensitive sensors for acceleration sensitivity below the kilohertz scale.In order to improve the measurement range,we utilize a sensor whose resonance frequencyω0 could be adjusted from 0.1 Hz to 100 Hz.The limits of the coupling constant gB-Lare improved by more than 10 times compared to previous reports,and it may be possible to achieve higher accuracy by using the array of sensors in the future.
文摘This study aims to analyze the clinical use of ornidazole injection at the post-marketing stage by centralized hospital monitoring system method,and investigate its widespread use in patients,in order to regulate and guide the rational drug use,improve the drug specificity and provide a basis for drug therapy.The study adopts a prospective,multi-center,large sample size,centralized hospital monitoring system.We selected five leading hospitals in Hubei province,and observed the inpatients who received the ornidazole injection from July 1,2015 to October 31,2015.The basic information of patients was recorded,as well as the drug use and adverse events.The statistical analysis was performed based on these data.A total of 4396 individuals were enrolled in this study,most of them were middle-aged female patients and the ornidazole injection was mainly used as prophylactic prior to surgery to prevent the infections,and surgical treatment of anaerobic infections,abdominal infections and pelvic infections.The irrational drug use existed mainly in the prescribing and administration process,including unreasonable dosing frequency,rapid intravenous drip speed and extended duration of drug use.Eleven cases of adverse reactions were collected during the monitoring,incidence rate of adverse reactions was 2.5‰;adverse drug reactions occurred within 30 min.The study results fully reflected the usage of ornidazole injection in the real world.Based on the study,we calculated the adverse reaction incidence of ornidazole and identified the risk factors which may affect the safety of ornidazole injection.Study results strongly recommend that the manufacturers should publish standards for inpatient use and doctors should prescribe with caution accordingly.
基金supported by Open Fund of State Key Laboratory of Oral Diseases,Sichun University
文摘This paper aims to investigate if the dental restoration of nickel-chromium based alloy(Ni-Cr) leads to the enhanced excretions of Ni and Cr in urine.Seven hundred and ninety-five patients in a dental hospital had single or multiple Ni-Cr alloy restoration recently and 198 controls were recruited to collect information on dental restoration by questionnaire and clinical examination.Urinary concentrations of Ni and Cr from each subject were measure by graphite furnace atomic absorption spectrometry.Compared to the control group,the urinary level of Ni was significantly higher in the patient group of < 1 month of the restoration duration,among which higher Ni excretions were found in those with either a higher number of teeth replaced by dental alloys or a higher index of metal crown not covered with the porcelain.Urinary levels of Cr were significantly higher in the three patient groups of <1,1 to <3 and 3 to <6 months,especially in those with a higher metal crown exposure index.Linear curve estimations showed better relationships between urinary Ni and Cr in patients within 6-month groups.Our data suggested significant increased excretions of urinary Ni and Cr after dental restoration.Potential short- and long-term effects of Ni-Cr alloy restoration need to be investigated.
基金Supported by the National Key R&D Program of China(Grant No.2018YFA0306600)the Chinese Academy of Sciences(Grant Nos.GJJSTD20170001 and QYZDY-SSW-SLH004)Anhui Initiative in Quantum Information Technologies(Grant No.AHY050000).
文摘Fluidics is one of the most historic subjects that are well-established over centuries on the macroscopic scale.In recent years,fluid detection using a number of micro/nano scale devices has been achieved.However,the interaction of microfluid and solid devices on micro/nano-meter scale still lacks in-depth research.We demonstrate a practical nanomechanical detector for microfluidics via a string resonator with high Q-factor,suspended over a hole.This device is placed under a jet nozzle with several microns of diameter,and the interaction between the micro-gas flow and the resonator is observed by monitoring the variation of the fundamental frequency and the quality factor.Moreover,we manage to measure the fluctuations of the micro-gas flow on the nanomechanical resonator by means of stochastic resonance.This work manifests a potential platform for detecting dynamical fluid behaviors at microscopic scale for novel fluid physics.
文摘We realize a coherent transfer of mechanical excitation in a finely controlled artificial nanomechanical lattice.We also realize strong dynamic coupling between adjacent high-Q mechanical resonators,via modulated dielectric force at the frequency difference between them.An excitation transfer across a lattice consisting of 7 nanobeams is observed by applying a design sequence of switching for couplings,with the final effective population reaching 0.94.This work not only demonstrates the ability to fully control an artificial lattice but also provides an efficient platform for studying complicated dynamics in one-dimensional systems.
基金Supported by the Fundamental Research Funds for the Central Universities(Grant No.WK2030000032)the National Key R&D Program of China(Grant No.2018YFA0306600)+1 种基金the CAS(Grant Nos.GJJSTD20170001 and QYZDY-SSW-SLH004)Anhui Initiative in Quantum Information Technologies(Grant No.AHY050000).
文摘Physical systems with gain and loss can be described by a non-Hermitian Hamiltonian,which is degenerated at the exceptional points(EPs).Many new and unexpected features have been explored in the non-Hermitian systems with a great deal of recent interest.One of the most fascinating features is that chiral state conversion appears when one EP is encircled dynamically.Here,we propose an easy-controllable levitated microparticle system that carries a pair of EPs and realize slow evolution of the Hamiltonian along loops in the parameter plane.Utilizing the controllable rotation angle,gain and loss coefficients,we can control the structure,size and location of the loops in situ.We demonstrate that,under the joint action of topological structure of energy surfaces and nonadiabatic transitions,the chiral behavior emerges both along a loop encircling an EP and even along a straight path away from the EP.This work broadens the range of parameter space for the chiral state conversion,and proposes a useful platform to explore the interesting properties of exceptional points physics.
基金supported by the National Natural Science Foundation of China under Grant 62172059,61972057 and 62072055Hunan Provincial Natural Science Foundations of China under Grant 2020JJ4626+1 种基金Scientific Research Fund of Hunan Provincial Education Department of China under Grant 19B004Postgraduate Scientific Research Innovation Project of Hunan Province under Grant CX20210811.
文摘Image inpainting based on deep learning has been greatly improved.The original purpose of image inpainting was to repair some broken photos, suchas inpainting artifacts. However, it may also be used for malicious operations,such as destroying evidence. Therefore, detection and localization of imageinpainting operations are essential. Recent research shows that high-pass filteringfull convolutional network (HPFCN) is applied to image inpainting detection andachieves good results. However, those methods did not consider the spatial location and channel information of the feature map. To solve these shortcomings, weintroduce the squeezed excitation blocks (SE) and propose a high-pass filter attention full convolutional network (HPACN). In feature extraction, we apply concurrent spatial and channel attention (scSE) to enhance feature extraction and obtainmore information. Channel attention (cSE) is introduced in upsampling toenhance detection and localization. The experimental results show that the proposed method can achieve improvement on ImageNet.
基金supported by Xi’an Jiaotong University Education Program,Shanxi Province Science and Technology Project(Program No.2004K17-G11)Chinese National Natural Sciences Grant No.30471826
文摘Objective： Throughout the world, fetal growth restriction（FGR） is one of the most severe complications occurring during pregnancy. It is subsequently associated with neurologic abnormalities in chldren. Our aim was to investigate the spatial learning and memory ability of rat offspring born With FGR. Methods：A rat model of FGR was constructed using the method of passive smoking. Spatial learning and memory were studied in rat offspring born with FGR by assessing the animals＇ performance using the Morris water maze task. Results： At 1- and 2- months of age, both female and male offspring rats showed impairment of performance, while at 4 months of age, only female rats showed impaired performance. The FGR offspring spent a longer time swimming and used inefficient strategies（P〈 0.05, respectively）. However, there were no significant maze performance FGR effects in the 4 month old male rats. In all groups of FGR offspring, irrespective of age or sex, the time spent in the platform quadrant by the rat was significantly less than that in the control group（P〈 0.05）. Conclusion： The Morris water maze performance decreased in rat offspring born with FGR. It is suggested that FGR can cause impairments of spatial learning and memory in young animals.
基金financially supported by the Second Tibetan Plateau Scientific Expedition and Research(Grant No.2019QZKK0706)。
文摘The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in fossils.It records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern hemisphere.Thus,it is of great significance for explaining the global paleogeographic evolution,tectonic activities and biodiversity changes during this critical period.The blocks on both sides of the southern Tienshan suture zone and the Longmu Co-ShuanghuChangning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions,showing important tectonic paleogeographic partitioning significance.The two suture zones represent the main branches of the PaleoAsian Ocean and the Paleo-Tethys Ocean,respectively,and on this basis the Devonian System can be subdivided into three types:the Tienshan type,the Tethys type and the Gondwana type.Based on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas,this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction,providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of Gondwana.The results indicate that the North Qiangtang,South Qiangtang,Simao,Baoshan and Tengchong terranes,as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block,while the Lhasa Terrane has affinities with the Australian Block,and may be located between the South China and Australian blocks.In the Emsian(Early Devonian),the South China Block separated from the northern margin of Gondwana,a process that was accompanied by the opening of the Jinshajiang-Ailaoshan Ocean.In the Middle Devonian,the mid-oceanic ridge of the Paleo-Tethys Ocean expanded rapidly,corresponding with a global sea-level rise,the widespread development of carbonate platforms and nadir values of Devonian seawater strontium isotopes.By the Late Devonian,the Paleo-Tethys Ocean had reached a considerable size,leading to abundant occurrences of Upper Devonian radiolarian cherts in the Paleo-Tethys suture zones.
文摘Marginal Fisher analysis （MFA） is a repre- sentative margin-based learning algorithm for face recognition. A major problem in MFA is how to select appropriate parameters, k1 and k2, to construct the respective intrinsic and penalty graphs. In this paper, we propose a novel method called nearest-neighbor （NN） classifier motivated marginal discriminant projections （NN-MDP）. Motivated by the NN classifier, NN-MDP seeks a few projection vectors to prevent data samples from being wrongly categorized. Like MFA, NN-MDP can characterize the compactness and separability of samples simultaneously. Moreover, in contrast to MFA, NN-MDP can actively construct the intrinsic graph and penalty graph without unknown parameters. Experimental results on the 0RL, Yale, and FERET face databases show that NN-MDP not only avoids the intractability, and high expense of neighborhood parameter selection, but is also more applicable to face recognition with NN classifier than other methods.
基金supported by the National Natural Science Foundation of China(81788101,11227901,11722544 and 91636217)the Chinese Academy of Sciences(GJJSTD20170001and QYZDY-SSW-SLH004)the National Key Research and Development Program of China(2013CB921800,2016YFA0502400)
文摘Open quantum systems are always exposed to an external environment,which result in interacting and exchanging information between quantum systems and their surroundings.The dynamics of real open quantum systems are often expected to deviate from the idealized Markovian process of losing information to their surrounding environment and to exhibit non-Markovian
基金the Medical Scientific Research of Zhejiang Province(Nos.2009A044 and 2015KYA055)the Natural Science Foundation of Zhejiang Province(No.LY13H130001)+2 种基金the Program of Science Technology Department(No.2013C33208)the Program of Traditional Chinese Medicine Administration of Zhejiang Province(No.2012ZA085)China
文摘Laryngeal squamous cell carcinoma(LSCC)is the most common type of head and neck squamous cell carcinoma(HNSCC)worldwide.Protein phosphatase 2A(PP2A)dysfunction has been widely reported in a broad range of malignancies due to its distinctive role in miscellaneous cellular processes.However,it is poorly understood whether aberrant alterations of PP2A are involved in the network of oncogenic events in LSCC.Here,we detected a panel of PP2A-associated proteins using western blot in both laryngeal squamous cell carcinoma tissues and paired adjacent normal tissues from patients(Data S1).We found that phospho-PP2A/C(Y307),α4,cancerous inhibitor of protein phosphatase 2A(CIP2A),Akt,ezrin,phospho-ezrin(T567),14-3-3,and focal adhesion kinase(FAK)showed increased expression levels in carcinoma tissues relative to normal tissues,while phospho-Akt(T308)showed decreased levels.Our study,thus,provides a rationale for targeting PP2A to develop novel therapies and proposes a combination of interrelated biomarkers for the diagnostic evaluation and prognosis prediction in LSCC.
基金This work is supported by National Natural Science Foundation of China(Grant Nos.11804230,11774239,61827815)Shenzhen Science and Technology Innovation Commission(Grant Nos.KQTD20170810105439418,KQTD20180412181422399,JCYJ20180507181858539,ZDSYS201707271554071)High-Level University Construction Funds of SZU(Grant No.860-000002081209 and 860-000002110711).
文摘Monolayers of layered materials,such as graphite and molybdenum dichalcogenides,have been the focus of materials science in the last decades.Here,we reveal benign stability and intriguing physical properties in the thinnest monolayer wurtzite(wz)semiconductors,which can be exfoliated from their bulk and stacked to reform the wz crystals.The candidate ZnX and CdX(X=S,Se,Te)monolayers possess low cleavage energy and direct bandgaps,which harbor strongly coupled ferroelectricity and ferroelasticity with low transition barriers,giant in-plane negative Poisson’s ratio,as well as giant Rashba spin splitting,enabling the co-tunability of spin splitting and auxetic magnitudes via multiferroic switching.These wz monolayers can be used as building blocks of devices structures,due to their inherent“self-healable”capacity,which offer more flexibility for semiconductor fabrication and provide a natural platform to probe the interplay of multiple physical effects,bringing light into the rich physics in tetrahedral semiconductors.
基金This work was supported by the China Scholarship Council Fund(No.201808140223)the National Natural Science Foundation of China(No.11661020).
文摘The present paper is concerned with stability and L_(2) gain analysis of switched distributed parameter system(SDPS)with time delay.First,exponential stability is discussed,and the state decay estimate of the system is explicitly given by using linear matrix inequalities(LMIs)incorporating with the average dwell time(ADT)method.Second,L_(2) gain analysis is also studied.At last,illustrative examples are given to show the effectiveness of the proposed method.The main contribution of the paper is:some criteria of exponential stability and L_(2) gain for multiple-input multiple-output(MIMO)switched PDE are developed in the form of LMIs and ADT signal for the first time.The advantage of the work is we generalize the application range of the related research.The proposed method is expected to provide an effective tool for stability and H∞control analysis of SDPS.
