The dispersion curves of bulk waves propagating in both AlN and ZnO film bulk acoustic resonators(FBARs)are presented to illustrate the mode flip of the thickness-extensional(TE)and 2nd thickness-shear(TSh2)modes.The ...The dispersion curves of bulk waves propagating in both AlN and ZnO film bulk acoustic resonators(FBARs)are presented to illustrate the mode flip of the thickness-extensional(TE)and 2nd thickness-shear(TSh2)modes.The frequency spectrum quantitative prediction(FSQP)method is used to solve the frequency spectra for predicting the coupling strength among the eigen-modes in AlN and ZnO FBARs.The results elaborate that the flip of the TE and TSh2 branches results in novel self-coupling vibration between the small-wavenumber TE and large-wavenumber TE modes,which has never been observed in the ZnO FBAR.Besides,the mode flip leads to the change in the relative positions of the frequency spectral curves about the TE cut-off frequency.The obtained frequency spectra can be used to predict the mode-coupling behaviors of the vibration modes in the AlN FBAR.The conclusions drawn from the results can help to distinguish the desirable operation modes of the AlN FBAR with very weak coupling strength from all vibration modes.展开更多
[Objective] This study aimed to investigate the effects of heat shock factor AtHsf A1 a on Caspase-3 activity in Arabidopsis thaliana under high temperature stress,thus revealing the relationship between heat shock fa...[Objective] This study aimed to investigate the effects of heat shock factor AtHsf A1 a on Caspase-3 activity in Arabidopsis thaliana under high temperature stress,thus revealing the relationship between heat shock factor At Hsf A1 a and programmed cell death in A. thaliana. [Method] Different genotypes of A. thaliana( AtHsf A1a-silenced transgenic and wild-type) seedlings were treated at 42 ℃. According to the fragmentation level of fluorogenic substrate Ac-DEVDp NA,Caspase-3 activity was determined by spectrophotometry. [Result]After high temperature treatment,Caspase-3 activity in A. thaliana was enhanced significantly. Caspase-3 activity in At Hsf A1a-silenced transgenic A. thaliana was higher than that in wild-type A. thaliana,which indicated that At Hsf A1 a could inhibit Caspase-3 activity in A. thaliana under high temperature stress. [Conclusion] Under high temperature stress,heat shock factor At Hsf A1 a might exert inhibitory effects on programmed cell death by reducing Caspase-3 activity. This study provided the basis for clarifying the mechanism of stress resistance in plants.展开更多
[Objective] This study aimed to screen target genes regulated by heat shock factor AtHsfA1a in Arabidopsis thaliana. [Method] Using AtHsfA1a-inserted mutant athsfa1a( SALK-068042) and wild-type A. thaliana seedlings a...[Objective] This study aimed to screen target genes regulated by heat shock factor AtHsfA1a in Arabidopsis thaliana. [Method] Using AtHsfA1a-inserted mutant athsfa1a( SALK-068042) and wild-type A. thaliana seedlings as experimental materials,target genes regulated by heat shock factor AtHsfA1a were screened by microarray assay. Differentially expressed genes were screened by multiple method. Specific functions of differentially expressed genes were analyzed by gene ontology( GO) analysis. Signal transduction pathways,in which differentially expressed genes were involved,were analyzed by pathway analysis. Gene-gene interaction network was constructed by Signal-Net. [Result]A total of 3 672 differentially expressed genes were screened out. Up-regulated differentially expressed genes were involved in 198 functions and 7 signal transduction pathways; down-regulated differentially expressed genes were involved in 94 functions and 10 signal transduction pathways. In the signal transduction network,it was found that cwINV4 and HXK3 had relatively high ability of mediation; AT1G14240 and cwINV4 exhibited the most interactions with other genes,which were located in key positions throughout the gene-gene interaction network. [Conclusion] Heat shock factor AtHsfA1a regulates a large number of target genes in A. thaliana.展开更多
[Objective] This study aimed to investigate the effects of heat shock factor AtHsfA1a on programmed cell death in Arabidopsis thaliana under cold stress. [Method] AtHsfA1a-silenced transgenic( NT) and wild-type( WT) A...[Objective] This study aimed to investigate the effects of heat shock factor AtHsfA1a on programmed cell death in Arabidopsis thaliana under cold stress. [Method] AtHsfA1a-silenced transgenic( NT) and wild-type( WT) A. thaliana seedlings were used as experimental materials to induce the formation of callus; the callus were cultured to single cells by suspension culture,subjected to cold stress,stained with DAPI,prepared into cell smears and observed under a fluorescence microscope. [Result] Under cold stress,cell nucleus of wild-type A. thaliana displayed morphological changes,but no apoptotic bodies were found;apoptotic bodies were observed in AtHsfA1a-silenced transgenic A. thaliana cells,and the cytoplasm was remarkably concentrated. [Conclusion] Under cold stress,heat shock factor AtHsfA1a exerted inhibitory effects on programmed cell death in A. thaliana,which was of great significance for clarifying the mechanism of stress responses in plants.展开更多
The investigation focusing on the mechanical behaviors at the microstructural level in composite materials can provide valuable insight into the failure mechanisms at larger scales.A micromechanics damage model which ...The investigation focusing on the mechanical behaviors at the microstructural level in composite materials can provide valuable insight into the failure mechanisms at larger scales.A micromechanics damage model which comprises the coupling of the matrix constitutive model and the cohesive zone(CZM)model at fiber-matrix interfaces is presented to evaluate the transverse tensile damage behaviors of unidirectional(UD)fiber-reinforced polymer(FRP)composites.For the polymeric matrix that exhibits highly non-linear mechanical responses,special focus is paid on the formulation of the constitutive model,which characterizes a mixture of elasticity,plasticity as well as damage.The proposed constitutive model includes the numerical implementation of a fracture plane based ellipse-parabola criterion that is an extension of the classic Mohr-Coulomb criterion,corresponding post-yield flow rule and post-failure degradation rule in the fully implicit integration scheme.The numerical results are in good agreement with experimental measurements.It is found that directly using the matrix properties measured at the ply level to characterize the mechanical responses at the constituent level may bring large discrepancies in homogenized stress-strain responses and dominant failure mechanisms.The distribution of fracture plane angles in matrix is predicted,where it is shown to provide novel insight into the microscopic damage initiation and accumulation under transverse tension.展开更多
In this paper,we propose a specific two-layer model consisting of a functionally graded(FG)layer and a piezoelectric semiconductor(PS)layer.Based on the macroscopic theory of PS materials,the effects brought about by ...In this paper,we propose a specific two-layer model consisting of a functionally graded(FG)layer and a piezoelectric semiconductor(PS)layer.Based on the macroscopic theory of PS materials,the effects brought about by the attached FG layer on the piezotronic behaviors of homogeneous n-type PS fibers and PN junctions are investigated.The semi-analytical solutions of the electromechanical fields are obtained by expanding the displacement and carrier concentration variation into power series.Results show that the antisymmetry of the potential and electron concentration distributions in homogeneous n-type PS fibers is destroyed due to the material inhomogeneity of the attached FG layer.In addition,by creating jump discontinuities in the material properties of the FG layer,potential barriers/wells can be produced in the middle of the fiber.Similarly,the potential barrier configuration near the interface of a homogeneous PS PN junction can also be manipulated in this way,which offers a new choice for the design of PN junction based devices.展开更多
Root meristem activity is essential for root morphogenesis and adaptation,but the molecular mechanism regulating root meristem activity is not fully understood.Here,we identify an F-box family E3 ubiquitin ligase name...Root meristem activity is essential for root morphogenesis and adaptation,but the molecular mechanism regulating root meristem activity is not fully understood.Here,we identify an F-box family E3 ubiquitin ligase named SHORT PRIMARY ROOT(SHPR) that regulates primary root(PR)meristem activity and cell proliferation in rice.SHPR loss-of-function mutations impair PR elongation in rice.SHPR is involved in the formation of an SCF complex with the Oryza sativa SKP1-like protein OSK1/20.We show that SHPR interacts with Oryza sativa SEUSS-LIKE(OsSLK) in the nucleus and is required for OsSLK polyubiquitination and degradation by the ubiquitin 26S-proteasome system(UPS).Transgenic plants overexpressing OsSLK display a shorter PR phenotype,which is similar to the SHPR loss-of-function mutants.Genetic analysis suggests that SHPR promotes PR elongation in an OsSLK-dependent manner.Collectively,our study establishes SHPR as an E3 ubiquitin ligase that targets OsSLK for degradation,and uncovers a protein ubiquitination pathway as a mechanism for modulating root meristem activity in rice.展开更多
We study the effects of mechanical nonlinearity arising from large thickness-shear deformation on the transient process of an AT-cut quartz plate resonator. Mindlin's two-dimensional plate equation is used, from w...We study the effects of mechanical nonlinearity arising from large thickness-shear deformation on the transient process of an AT-cut quartz plate resonator. Mindlin's two-dimensional plate equation is used, from which a system of first-order nonlinear differential equations governing the evolution of the vibration amplitude is obtained. Numerical solutions by the Runge-Kutta method show that in common operating conditions of quartz resonators the nonlinear effect varies from noticeable to significant. As resonators are to be made smaller and thinner in the future with about the same power requirement, nonlinear effects will become more important and need more understanding and consideration in resonator design.展开更多
In this paper,we present an approach to studying the mode coupling vibrations in two-port thin-film bulk acoustic wave resonator(FBAR)devices with two pairs of electrodes deposited on the zinc oxide film.The two-dimen...In this paper,we present an approach to studying the mode coupling vibrations in two-port thin-film bulk acoustic wave resonator(FBAR)devices with two pairs of electrodes deposited on the zinc oxide film.The two-dimensional plate theory established in our previous work is employed,which takes into account the coupling of the operating thickness-extensional mode with the extensional,flexural,fundamental and second-order thickness-shear modes.The propagation of straight-crested waves in the plate is studied,and the state-vector approach is successfully used to simplify the derivation process.For a structurally symmetric device,the modes are separated into quasi symmetric and antisymmetric ones.Frequency spectra and corresponding mode shapes are obtained under the stress-free boundary conditions,respectively,and then coupling effects and energy trapping phenomenon are discussed in detail.Some results for structures with asymmetric electrode distributions are also shown.It is found that the choice of aspect ratio has a great effect on mode couplings of FBAR devices.This study will be useful for the design of FBAR filters and sensors.展开更多
Permutation polynomials with low differential uniformity and high nonlinearity are preferred in cryptographic systems. In 2018, Tu, Zeng and Helleseth constructed a new class of permutation quadrinomials over the fini...Permutation polynomials with low differential uniformity and high nonlinearity are preferred in cryptographic systems. In 2018, Tu, Zeng and Helleseth constructed a new class of permutation quadrinomials over the finite field F_(2 2m) for an odd integer m. In this paper, we aim to investigate the differential uniformity and nonlinearity of this class of permutation polynomials so as to find 4-uniform permutation polynomials with high nonlinearity.展开更多
Handwriting expertise,as a form of forensic evidence,was once considered by most courts under the Anglo-American law system to be infallible,but this position was significantly challenged by the Daubert case(1993)and ...Handwriting expertise,as a form of forensic evidence,was once considered by most courts under the Anglo-American law system to be infallible,but this position was significantly challenged by the Daubert case(1993)and further by the President’s Council of Advisors on Science and Technology report published in 2016.In China,handwriting expertise has often been accepted as forensic evidence.However,this does not mean that there is no need to review the reliability of handwriting expertise.In this study,we analyze the current situation in China regarding the reliability of handwriting identification using cases from China’s judicial judgment database.We intend to identify the reasons for rejection of handwriting expertise,analyze the outcomes of applications for re-examination,and examine the court’s evaluation of different forensic opinions in relation to a given case.We also propose ways to strengthen the reliability of handwriting identification in China.展开更多
Lambda-cyhalothrin(LCT),one of the type II pyrethroids,has been widely used throughout the world.The estrogenic effect of LCT to increase cell proliferation has been well established.However,whether the estrogenic eff...Lambda-cyhalothrin(LCT),one of the type II pyrethroids,has been widely used throughout the world.The estrogenic effect of LCT to increase cell proliferation has been well established.However,whether the estrogenic effect of LCT will influence neurodevelopment has not been investigated.In addition,17β-Estradiol(E2)plays a crucial role in neurodevelopment and induces an increase in synaptic proteins.The post-synaptic density 95(PSD95)protein,which is involved in the development of the structure and function of new spines and localized with estrogen receptor α(ERα)at the post-synaptic density(PSD),was detected in our study by using hippocampal neuron cell line HT22.We found that LCT up-regulated PSD95 and ERα expression,estrogen receptor(ER)antagonist ICI182,780 and phosphatidylinositol-4;5-bisphosphate 3-kinase(PI3K)inhibitor LY294,002 blocked this effect.In addition,LCT disrupted the promotion effect of E2 on PSD95.To investigate whether the observed changes are caused by ERα-dependent signaling activation,we next detected the effects of LCT on the ERα-mediated PI3K-Protein kinase B(PKB/Akt)-eukaryotic initiation factor(e IF)4E-binding protein 1(4E-BP1)pathway.There existed an activation of Akt and the downstream factor 4E-BP1 after LCT treatment.In addition,LCT could disrupt the activation effect of E2 on the Akt pathway.However,no changes in c AMP response element-binding protein(CREB)activation and PSD95 messenger ribonucleic acid(m RNA)were observed.Our findings demonstrated that LCT could increase the PSD95 protein level via the ERα-dependent Akt pathway,and LCT might disrupt the up-regulation effect of E2 on PSD95 protein expression via this signaling pathway.展开更多
Copper sulfide(Cu_(x)S)as a plasmonic solar photothermal semiconductor material that expands the light collection range by altering localized surface plasmon resonance(LSPR)to the near-to mid-infrared(IR)spectral regi...Copper sulfide(Cu_(x)S)as a plasmonic solar photothermal semiconductor material that expands the light collection range by altering localized surface plasmon resonance(LSPR)to the near-to mid-infrared(IR)spectral region.The versatile synthesis strategies of Cu_(x)S nanostructure offer its variability of morphology and provide additional freedom in tuning the optical property.Particularly,nanocage(or nanoshell)has hybridized plasmon resonances as a result of super-positioned nanosphere and nanocavity,which extends its receiving range of solar spectrum and increases light-to-heat conversion rate.Here,we offer novel“nanoink”and“nanofilm”developed from colloidal Cu_(27)S_(24)nanocages with excellent solar photothermal response.Via combining experimental measurement and theoretical calculation,we estimated the optical properties of covellite Cu_(27)S_(24).And based on obtained dielectric functions,we then calculated its solar photothermal performance,which was further validated by our experimental measurement.The simulation results showed that hollow Cu_(27)S_(24)nanocages have excellent solar photothermal performance,and exhibit much higher solar photothermal conversion efficiency than solid Cu_(27)S_(24)nanospheres.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.11872329,12192211,and 12072315)the Natural Science Foundation of Zhejiang Province of China(No.LD21A020001)+1 种基金the National Postdoctoral Program for Innovation Talents of China(No.BX2021261)the China Postdoctoral Science Foundation Funded Project(No.2022M722745)。
文摘The dispersion curves of bulk waves propagating in both AlN and ZnO film bulk acoustic resonators(FBARs)are presented to illustrate the mode flip of the thickness-extensional(TE)and 2nd thickness-shear(TSh2)modes.The frequency spectrum quantitative prediction(FSQP)method is used to solve the frequency spectra for predicting the coupling strength among the eigen-modes in AlN and ZnO FBARs.The results elaborate that the flip of the TE and TSh2 branches results in novel self-coupling vibration between the small-wavenumber TE and large-wavenumber TE modes,which has never been observed in the ZnO FBAR.Besides,the mode flip leads to the change in the relative positions of the frequency spectral curves about the TE cut-off frequency.The obtained frequency spectra can be used to predict the mode-coupling behaviors of the vibration modes in the AlN FBAR.The conclusions drawn from the results can help to distinguish the desirable operation modes of the AlN FBAR with very weak coupling strength from all vibration modes.
基金Supported by National Natural Science Foundation of China(31260061,31060039)Project of Key Laboratory of Special Biological Resource Development and Utilization of Universities in Yunnan Province(GXZD201601)+1 种基金Key Discipline Construction Project of Kunming UniversityNational College Students' Innovation Project of China
文摘[Objective] This study aimed to investigate the effects of heat shock factor AtHsf A1 a on Caspase-3 activity in Arabidopsis thaliana under high temperature stress,thus revealing the relationship between heat shock factor At Hsf A1 a and programmed cell death in A. thaliana. [Method] Different genotypes of A. thaliana( AtHsf A1a-silenced transgenic and wild-type) seedlings were treated at 42 ℃. According to the fragmentation level of fluorogenic substrate Ac-DEVDp NA,Caspase-3 activity was determined by spectrophotometry. [Result]After high temperature treatment,Caspase-3 activity in A. thaliana was enhanced significantly. Caspase-3 activity in At Hsf A1a-silenced transgenic A. thaliana was higher than that in wild-type A. thaliana,which indicated that At Hsf A1 a could inhibit Caspase-3 activity in A. thaliana under high temperature stress. [Conclusion] Under high temperature stress,heat shock factor At Hsf A1 a might exert inhibitory effects on programmed cell death by reducing Caspase-3 activity. This study provided the basis for clarifying the mechanism of stress resistance in plants.
基金Supported by National Natural Science Foundation of China(31260061,31060039)Key Laboratory of Special Biological Resource Development and Utilization of Universities in Yunnan Province(GXZD201601)+1 种基金Key Discipline Construction Project of Kunming UniversityNational College Students'Innovation Project of China
文摘[Objective] This study aimed to screen target genes regulated by heat shock factor AtHsfA1a in Arabidopsis thaliana. [Method] Using AtHsfA1a-inserted mutant athsfa1a( SALK-068042) and wild-type A. thaliana seedlings as experimental materials,target genes regulated by heat shock factor AtHsfA1a were screened by microarray assay. Differentially expressed genes were screened by multiple method. Specific functions of differentially expressed genes were analyzed by gene ontology( GO) analysis. Signal transduction pathways,in which differentially expressed genes were involved,were analyzed by pathway analysis. Gene-gene interaction network was constructed by Signal-Net. [Result]A total of 3 672 differentially expressed genes were screened out. Up-regulated differentially expressed genes were involved in 198 functions and 7 signal transduction pathways; down-regulated differentially expressed genes were involved in 94 functions and 10 signal transduction pathways. In the signal transduction network,it was found that cwINV4 and HXK3 had relatively high ability of mediation; AT1G14240 and cwINV4 exhibited the most interactions with other genes,which were located in key positions throughout the gene-gene interaction network. [Conclusion] Heat shock factor AtHsfA1a regulates a large number of target genes in A. thaliana.
基金Supported by National Natural Science Foundation of China(31260061,31060039)Key Laboratory of Special Biological Resource Development and Utilization of Universities in Yunnan Province(GXZD201601)+1 种基金Key Discipline Construction Project of Kunming UniversityNational College Students Innovation Project of China
文摘[Objective] This study aimed to investigate the effects of heat shock factor AtHsfA1a on programmed cell death in Arabidopsis thaliana under cold stress. [Method] AtHsfA1a-silenced transgenic( NT) and wild-type( WT) A. thaliana seedlings were used as experimental materials to induce the formation of callus; the callus were cultured to single cells by suspension culture,subjected to cold stress,stained with DAPI,prepared into cell smears and observed under a fluorescence microscope. [Result] Under cold stress,cell nucleus of wild-type A. thaliana displayed morphological changes,but no apoptotic bodies were found;apoptotic bodies were observed in AtHsfA1a-silenced transgenic A. thaliana cells,and the cytoplasm was remarkably concentrated. [Conclusion] Under cold stress,heat shock factor AtHsfA1a exerted inhibitory effects on programmed cell death in A. thaliana,which was of great significance for clarifying the mechanism of stress responses in plants.
基金support by National Science Foundation for Young Scientists of China under Grant[No.11802116].
文摘The investigation focusing on the mechanical behaviors at the microstructural level in composite materials can provide valuable insight into the failure mechanisms at larger scales.A micromechanics damage model which comprises the coupling of the matrix constitutive model and the cohesive zone(CZM)model at fiber-matrix interfaces is presented to evaluate the transverse tensile damage behaviors of unidirectional(UD)fiber-reinforced polymer(FRP)composites.For the polymeric matrix that exhibits highly non-linear mechanical responses,special focus is paid on the formulation of the constitutive model,which characterizes a mixture of elasticity,plasticity as well as damage.The proposed constitutive model includes the numerical implementation of a fracture plane based ellipse-parabola criterion that is an extension of the classic Mohr-Coulomb criterion,corresponding post-yield flow rule and post-failure degradation rule in the fully implicit integration scheme.The numerical results are in good agreement with experimental measurements.It is found that directly using the matrix properties measured at the ply level to characterize the mechanical responses at the constituent level may bring large discrepancies in homogenized stress-strain responses and dominant failure mechanisms.The distribution of fracture plane angles in matrix is predicted,where it is shown to provide novel insight into the microscopic damage initiation and accumulation under transverse tension.
基金国家重点研发项目(2022YFA1503200,2021YFC2101901)国家自然科学基金(22122103,21971108,21971111,22271144)+1 种基金中央高校基本科研业务费(020514380304,020514380252 and 020514380272)江苏省研究生科研与实践创新计划项目(KYCX22_0100).
基金supported by the National Natural Science Foundation of China(Nos.12061131013,11972276,1211101401,12172171,and 12102183)the State Key Laboratory of Mechanics and Control of Mechanical Structures of Nanjing University of Aeronautics and Astronautics(No.MCMS-E-0520K02)+5 种基金the Fundamental Research Funds for the Central Universities of China(Nos.NE2020002 and NS2019007)the National Natural Science Foundation of China for Creative Research Groups(No.51921003)the Postgraduate Research&Practice Innovation Program of Jiangsu Province of China(No.KYCX210179)the National Natural Science Foundation of Jiangsu Province of China(No.BK20211176)the Local Science and Technology Development Fund Projects Guided by the Central Government of China(No.2021Szvup061)the Jiangsu High-Level Innovative and Entrepreneurial Talents Introduction Plan(Shuangchuang Doctor Program,No.JSSCBS20210166)。
文摘In this paper,we propose a specific two-layer model consisting of a functionally graded(FG)layer and a piezoelectric semiconductor(PS)layer.Based on the macroscopic theory of PS materials,the effects brought about by the attached FG layer on the piezotronic behaviors of homogeneous n-type PS fibers and PN junctions are investigated.The semi-analytical solutions of the electromechanical fields are obtained by expanding the displacement and carrier concentration variation into power series.Results show that the antisymmetry of the potential and electron concentration distributions in homogeneous n-type PS fibers is destroyed due to the material inhomogeneity of the attached FG layer.In addition,by creating jump discontinuities in the material properties of the FG layer,potential barriers/wells can be produced in the middle of the fiber.Similarly,the potential barrier configuration near the interface of a homogeneous PS PN junction can also be manipulated in this way,which offers a new choice for the design of PN junction based devices.
基金supported by grants from the National Natural Science Foundation of China (31671516 and 31970806)。
文摘Root meristem activity is essential for root morphogenesis and adaptation,but the molecular mechanism regulating root meristem activity is not fully understood.Here,we identify an F-box family E3 ubiquitin ligase named SHORT PRIMARY ROOT(SHPR) that regulates primary root(PR)meristem activity and cell proliferation in rice.SHPR loss-of-function mutations impair PR elongation in rice.SHPR is involved in the formation of an SCF complex with the Oryza sativa SKP1-like protein OSK1/20.We show that SHPR interacts with Oryza sativa SEUSS-LIKE(OsSLK) in the nucleus and is required for OsSLK polyubiquitination and degradation by the ubiquitin 26S-proteasome system(UPS).Transgenic plants overexpressing OsSLK display a shorter PR phenotype,which is similar to the SHPR loss-of-function mutants.Genetic analysis suggests that SHPR promotes PR elongation in an OsSLK-dependent manner.Collectively,our study establishes SHPR as an E3 ubiquitin ligase that targets OsSLK for degradation,and uncovers a protein ubiquitination pathway as a mechanism for modulating root meristem activity in rice.
基金supported by the Program for New Century Excellent Talents in Universities(No.NCET-12-0625)the Natural Science Foundation for Distinguished Young Scholars of Jiangsu Province(No.SBK2014010134)+2 种基金the Fundamental Research Funds for Central Universities(No.NE2013101)the National Natural Science Foundation of China(No.11232007)a project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘We study the effects of mechanical nonlinearity arising from large thickness-shear deformation on the transient process of an AT-cut quartz plate resonator. Mindlin's two-dimensional plate equation is used, from which a system of first-order nonlinear differential equations governing the evolution of the vibration amplitude is obtained. Numerical solutions by the Runge-Kutta method show that in common operating conditions of quartz resonators the nonlinear effect varies from noticeable to significant. As resonators are to be made smaller and thinner in the future with about the same power requirement, nonlinear effects will become more important and need more understanding and consideration in resonator design.
基金This work was supported by the State Key Laboratory of Mechanics and Control of Mechanical Structures at NUAA[Grant No.MCMS-I-0518K02]the National Natural Science Foundation of China[Grant Nos.11502108.1611530686]+1 种基金the Natural Science Foundation of Jiangsu Province[Grant No.BK20140037]Iren Kuznetsova thanks Russian Foundation Basic Research Grant#18-29-23042 and Russian Ministry of Science and Education for partial financial support.
文摘In this paper,we present an approach to studying the mode coupling vibrations in two-port thin-film bulk acoustic wave resonator(FBAR)devices with two pairs of electrodes deposited on the zinc oxide film.The two-dimensional plate theory established in our previous work is employed,which takes into account the coupling of the operating thickness-extensional mode with the extensional,flexural,fundamental and second-order thickness-shear modes.The propagation of straight-crested waves in the plate is studied,and the state-vector approach is successfully used to simplify the derivation process.For a structurally symmetric device,the modes are separated into quasi symmetric and antisymmetric ones.Frequency spectra and corresponding mode shapes are obtained under the stress-free boundary conditions,respectively,and then coupling effects and energy trapping phenomenon are discussed in detail.Some results for structures with asymmetric electrode distributions are also shown.It is found that the choice of aspect ratio has a great effect on mode couplings of FBAR devices.This study will be useful for the design of FBAR filters and sensors.
基金This work was supported by the Application Foundation Frontier Project of Wuhan Science and Technology Bureau(No.2020010601012189)the National Natural Science Foundation of China(Nos.61761166010,62072162).
文摘Permutation polynomials with low differential uniformity and high nonlinearity are preferred in cryptographic systems. In 2018, Tu, Zeng and Helleseth constructed a new class of permutation quadrinomials over the finite field F_(2 2m) for an odd integer m. In this paper, we aim to investigate the differential uniformity and nonlinearity of this class of permutation polynomials so as to find 4-uniform permutation polynomials with high nonlinearity.
基金This research was funded by the Youth Scientist Program of the CUPL Science Research Project(2016),Grant No.16ZFQ82009.
文摘Handwriting expertise,as a form of forensic evidence,was once considered by most courts under the Anglo-American law system to be infallible,but this position was significantly challenged by the Daubert case(1993)and further by the President’s Council of Advisors on Science and Technology report published in 2016.In China,handwriting expertise has often been accepted as forensic evidence.However,this does not mean that there is no need to review the reliability of handwriting expertise.In this study,we analyze the current situation in China regarding the reliability of handwriting identification using cases from China’s judicial judgment database.We intend to identify the reasons for rejection of handwriting expertise,analyze the outcomes of applications for re-examination,and examine the court’s evaluation of different forensic opinions in relation to a given case.We also propose ways to strengthen the reliability of handwriting identification in China.
基金supported by the National Natural Science Foundation of China(No.H2607-30571585)
文摘Lambda-cyhalothrin(LCT),one of the type II pyrethroids,has been widely used throughout the world.The estrogenic effect of LCT to increase cell proliferation has been well established.However,whether the estrogenic effect of LCT will influence neurodevelopment has not been investigated.In addition,17β-Estradiol(E2)plays a crucial role in neurodevelopment and induces an increase in synaptic proteins.The post-synaptic density 95(PSD95)protein,which is involved in the development of the structure and function of new spines and localized with estrogen receptor α(ERα)at the post-synaptic density(PSD),was detected in our study by using hippocampal neuron cell line HT22.We found that LCT up-regulated PSD95 and ERα expression,estrogen receptor(ER)antagonist ICI182,780 and phosphatidylinositol-4;5-bisphosphate 3-kinase(PI3K)inhibitor LY294,002 blocked this effect.In addition,LCT disrupted the promotion effect of E2 on PSD95.To investigate whether the observed changes are caused by ERα-dependent signaling activation,we next detected the effects of LCT on the ERα-mediated PI3K-Protein kinase B(PKB/Akt)-eukaryotic initiation factor(e IF)4E-binding protein 1(4E-BP1)pathway.There existed an activation of Akt and the downstream factor 4E-BP1 after LCT treatment.In addition,LCT could disrupt the activation effect of E2 on the Akt pathway.However,no changes in c AMP response element-binding protein(CREB)activation and PSD95 messenger ribonucleic acid(m RNA)were observed.Our findings demonstrated that LCT could increase the PSD95 protein level via the ERα-dependent Akt pathway,and LCT might disrupt the up-regulation effect of E2 on PSD95 protein expression via this signaling pathway.
基金The authors acknowledge the finical support from the Key Laboratory Functional Molecular Solids,Ministry of Education(No.FMS202002)the National Key Research and Development Project(No.2020YFA0210703)+5 种基金the National Natural Science Foundation of China(Nos.U2032158,U2032159,and 62005292)the Key Research and Development Program of Anhui Province(Nos.S202104a05020085 and 201904a05020009)the Science and Technology Service Network Initiative of Chinese Academy of China(grant No.KFJ-STS-ZDTP-080)the Collaborative Innovation Program of Hefei Science Center,CAS(No.2020HSCCIP003)the Major Scientific and the CASHIPS Director’s Fund(No.YZJJZX202015)the Technological Innovation Projects of Shandong Province(No.2019JZZY020243).
文摘Copper sulfide(Cu_(x)S)as a plasmonic solar photothermal semiconductor material that expands the light collection range by altering localized surface plasmon resonance(LSPR)to the near-to mid-infrared(IR)spectral region.The versatile synthesis strategies of Cu_(x)S nanostructure offer its variability of morphology and provide additional freedom in tuning the optical property.Particularly,nanocage(or nanoshell)has hybridized plasmon resonances as a result of super-positioned nanosphere and nanocavity,which extends its receiving range of solar spectrum and increases light-to-heat conversion rate.Here,we offer novel“nanoink”and“nanofilm”developed from colloidal Cu_(27)S_(24)nanocages with excellent solar photothermal response.Via combining experimental measurement and theoretical calculation,we estimated the optical properties of covellite Cu_(27)S_(24).And based on obtained dielectric functions,we then calculated its solar photothermal performance,which was further validated by our experimental measurement.The simulation results showed that hollow Cu_(27)S_(24)nanocages have excellent solar photothermal performance,and exhibit much higher solar photothermal conversion efficiency than solid Cu_(27)S_(24)nanospheres.
