Metallic lithium anode is widely applied to building highenergy-density batteries such as lithium–sulfur and lithium–oxygen batteries because of its high specific capacity(3860 mAh g?1)and lowest negative potential(...Metallic lithium anode is widely applied to building highenergy-density batteries such as lithium–sulfur and lithium–oxygen batteries because of its high specific capacity(3860 mAh g?1)and lowest negative potential(?3.04 V vs.standard hydrogen electrode(SHE))[1,2].However,the practical applications of Li anode remain challenging[3–6].The large volume change during repeated plating/stripping of Li would cause mechanical and interfacial instability[7,8].The solid electrolyte interphase(SEI)layers on lithium surface with poor elasticity are vulnerable to crack under variable stress/strain,leading to continuous side reactions between exposed fresh Li and electrolyte[9–11].In addition,the uncontrollable nucleation and growth of Li incur the formation of dendrites,which could accelerate detrimental parasitic reactions.Because of the uneven stripping,dendritic Li may deteriorate into electrically disconnected or“dead”Li,resulting in poor Coulombic efficiency,rapid capacity decay,and short circuit risk[12–17].展开更多
In recent years,with the rapid development of deep learning technologies,some neural network models have been applied to generate fake media.DeepFakes,a deep learning based forgery technology,can tamper with the face ...In recent years,with the rapid development of deep learning technologies,some neural network models have been applied to generate fake media.DeepFakes,a deep learning based forgery technology,can tamper with the face easily and generate fake videos that are difficult to be distinguished by human eyes.The spread of face manipulation videos is very easy to bring fake information.Therefore,it is important to develop effective detection methods to verify the authenticity of the videos.Due to that it is still challenging for current forgery technologies to generate all facial details and the blending operations are used in the forgery process,the texture details of the fake face are insufficient.Therefore,in this paper,a new method is proposed to detect DeepFake videos.Firstly,the texture features are constructed,which are based on the gradient domain,standard deviation,gray level co-occurrence matrix and wavelet transform of the face region.Then,the features are processed by the feature selection method to form a discriminant feature vector,which is finally employed to SVM for classification at the frame level.The experimental results on the mainstream DeepFake datasets demonstrate that the proposed method can achieve ideal performance,proving the effectiveness of the proposed method for DeepFake videos detection.展开更多
0 INTRODUCTION The carbon buried in marine sediments in the form of organic carbon or carbonate minerals represents the largest pathway for carbon removal from Earth's surface environments(Sun and Turchyn,2014).Mi...0 INTRODUCTION The carbon buried in marine sediments in the form of organic carbon or carbonate minerals represents the largest pathway for carbon removal from Earth's surface environments(Sun and Turchyn,2014).Microbial sulfate reduction(MSR)is a fundamental biogeochemical process occurring in marine sediments,where sulfate-reducing bacteria(SRB)reduce sulfate(SO42-)to sulfide(S2-)using organic matter or methane as electron donors(Jorgensen,2021).展开更多
In this study,a wave flume experiment is implemented in order to investigate the effect of connector topology on the dynamic characteristics of a modular floating structure.Three configurations of flexible connectors ...In this study,a wave flume experiment is implemented in order to investigate the effect of connector topology on the dynamic characteristics of a modular floating structure.Three configurations of flexible connectors were designed for the experiment tests of a three-modular floating platform under various wave conditions.The results illustrate the module responses,relative displacements of connecting points between adjacent modules,and connector loads for floating structures with different types of connectors in the parameters region of non-dimensional module length.The comparison study demonstrates that the connector type III,which can provide appropriate constraint stiffness in all three degrees of freedom,generally delivers better dynamic stability to the floating platform.The longitudinal loads for the three types of connectors remain at the same level.Additionally,the mechanism of different types of connec-tors on the dynamic features of system is analyzed.This work can provide a few experimental guidelines for the connector design of floating structure in engineering practice.展开更多
With the prevalence of obesity and associated comorbidities,studies aimed at revealing mechanisms that regulate energy homeostasis have gained increasing interest.In 1994,the cloning of leptin was a milestone in metab...With the prevalence of obesity and associated comorbidities,studies aimed at revealing mechanisms that regulate energy homeostasis have gained increasing interest.In 1994,the cloning of leptin was a milestone in metabolic research.As an adipocytokine,leptin governs food intake and energy homeostasis through leptin receptors(LepR)in the brain.The failure of increased leptin levels to suppress feeding and elevate energy expenditure is referred to as leptin resistance,which encompasses complex pathophysiological processes.Within the brain,LepR-expressing neurons are distributed in hypothalamus and other brain areas,and each population of the LepR-expressing neurons may mediate particular aspects of leptin effects.In LepR-expressing neurons,the binding of leptin to LepR initiates multiple signaling cascades including janus kinase(JAK)–signal transducers and activators of transcription(STAT)phosphatidylinositol 3-kinase(PI3K)-protein kinase B(AKT),extracellular regulated protein kinase(ERK),and AMP-activated protein kinase(AMPK)signaling,etc.,mediating leptin actions.These findings place leptin at the intersection of metabolic and neuroendocrine regulations,and render leptin a key target for treating obesity and associated comorbidities.This review highlights the main discoveries that shaped the field of leptin for better understanding of the mechanism governing metabolic homeostasis,and guides the development of safe and effective interventions to treat obesity and associated diseases.展开更多
基金supported by MOST(2017YFA0206702)NSFC(21871149)+2 种基金MOE(B12015)Tianjin Project(18JCZDJC31100)the Fundamental Research Funds for the Central Universities.
文摘Metallic lithium anode is widely applied to building highenergy-density batteries such as lithium–sulfur and lithium–oxygen batteries because of its high specific capacity(3860 mAh g?1)and lowest negative potential(?3.04 V vs.standard hydrogen electrode(SHE))[1,2].However,the practical applications of Li anode remain challenging[3–6].The large volume change during repeated plating/stripping of Li would cause mechanical and interfacial instability[7,8].The solid electrolyte interphase(SEI)layers on lithium surface with poor elasticity are vulnerable to crack under variable stress/strain,leading to continuous side reactions between exposed fresh Li and electrolyte[9–11].In addition,the uncontrollable nucleation and growth of Li incur the formation of dendrites,which could accelerate detrimental parasitic reactions.Because of the uneven stripping,dendritic Li may deteriorate into electrically disconnected or“dead”Li,resulting in poor Coulombic efficiency,rapid capacity decay,and short circuit risk[12–17].
基金supported by the National Natural Science Foundation of China(Nos.U2001202,62072480,U1736118)the National Key R&D Program of China(Nos.2019QY2202,2019QY(Y)0207)+1 种基金the Key Areas R&D Program of Guangdong(No.2019B010136002)the Key Scientific Research Program of Guangzhou(No.201804020068).
文摘In recent years,with the rapid development of deep learning technologies,some neural network models have been applied to generate fake media.DeepFakes,a deep learning based forgery technology,can tamper with the face easily and generate fake videos that are difficult to be distinguished by human eyes.The spread of face manipulation videos is very easy to bring fake information.Therefore,it is important to develop effective detection methods to verify the authenticity of the videos.Due to that it is still challenging for current forgery technologies to generate all facial details and the blending operations are used in the forgery process,the texture details of the fake face are insufficient.Therefore,in this paper,a new method is proposed to detect DeepFake videos.Firstly,the texture features are constructed,which are based on the gradient domain,standard deviation,gray level co-occurrence matrix and wavelet transform of the face region.Then,the features are processed by the feature selection method to form a discriminant feature vector,which is finally employed to SVM for classification at the frame level.The experimental results on the mainstream DeepFake datasets demonstrate that the proposed method can achieve ideal performance,proving the effectiveness of the proposed method for DeepFake videos detection.
基金supported by the National Key Research and Development Program of China(No.2022YFE0136300)the National Natural Science Foundation of China(Nos.42276060,42076031)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2021YQ26)the Taishan Scholars Program of Shandong Province(No.tsqn201909057).
文摘0 INTRODUCTION The carbon buried in marine sediments in the form of organic carbon or carbonate minerals represents the largest pathway for carbon removal from Earth's surface environments(Sun and Turchyn,2014).Microbial sulfate reduction(MSR)is a fundamental biogeochemical process occurring in marine sediments,where sulfate-reducing bacteria(SRB)reduce sulfate(SO42-)to sulfide(S2-)using organic matter or methane as electron donors(Jorgensen,2021).
基金supported by the National Natural Science Foundation of China(Grant No.52071138)the Natural Science Foundation of Hunan Province(Grant No.2022JJ30120)the High-tech Ship Research Projects supported by the Ministry of Industry and Information Technology([2019]357).
文摘In this study,a wave flume experiment is implemented in order to investigate the effect of connector topology on the dynamic characteristics of a modular floating structure.Three configurations of flexible connectors were designed for the experiment tests of a three-modular floating platform under various wave conditions.The results illustrate the module responses,relative displacements of connecting points between adjacent modules,and connector loads for floating structures with different types of connectors in the parameters region of non-dimensional module length.The comparison study demonstrates that the connector type III,which can provide appropriate constraint stiffness in all three degrees of freedom,generally delivers better dynamic stability to the floating platform.The longitudinal loads for the three types of connectors remain at the same level.Additionally,the mechanism of different types of connec-tors on the dynamic features of system is analyzed.This work can provide a few experimental guidelines for the connector design of floating structure in engineering practice.
基金supported by grants from the National Natural Science Foundation of China(No.82170864.No.81471064.No.81670779,No.81870590 to R.Z)the Beijing Municipal Natural Science Foundation(No.7162097,No.H2018206641 to R.Z)+1 种基金the Peking University Research Foundation(No.BMU20140366 to R.Z)the National Key Research and Development Program of China(2017YFC1700402 to R.Z.).
文摘With the prevalence of obesity and associated comorbidities,studies aimed at revealing mechanisms that regulate energy homeostasis have gained increasing interest.In 1994,the cloning of leptin was a milestone in metabolic research.As an adipocytokine,leptin governs food intake and energy homeostasis through leptin receptors(LepR)in the brain.The failure of increased leptin levels to suppress feeding and elevate energy expenditure is referred to as leptin resistance,which encompasses complex pathophysiological processes.Within the brain,LepR-expressing neurons are distributed in hypothalamus and other brain areas,and each population of the LepR-expressing neurons may mediate particular aspects of leptin effects.In LepR-expressing neurons,the binding of leptin to LepR initiates multiple signaling cascades including janus kinase(JAK)–signal transducers and activators of transcription(STAT)phosphatidylinositol 3-kinase(PI3K)-protein kinase B(AKT),extracellular regulated protein kinase(ERK),and AMP-activated protein kinase(AMPK)signaling,etc.,mediating leptin actions.These findings place leptin at the intersection of metabolic and neuroendocrine regulations,and render leptin a key target for treating obesity and associated comorbidities.This review highlights the main discoveries that shaped the field of leptin for better understanding of the mechanism governing metabolic homeostasis,and guides the development of safe and effective interventions to treat obesity and associated diseases.
