Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results ca...Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features.展开更多
Electromyography(EMG)has already been broadly used in human-machine interaction(HMI)applications.Determining how to decode the information inside EMG signals robustly and accurately is a key problem for which we urgen...Electromyography(EMG)has already been broadly used in human-machine interaction(HMI)applications.Determining how to decode the information inside EMG signals robustly and accurately is a key problem for which we urgently need a solution.Recently,many EMG pattern recognition tasks have been addressed using deep learning methods.In this paper,we analyze recent papers and present a literature review describing the role that deep learning plays in EMG-based HMI.An overview of typical network structures and processing schemes will be provided.Recent progress in typical tasks such as movement classification,joint angle prediction,and force/torque estimation will be introduced.New issues,including multimodal sensing,inter-subject/inter-session,and robustness toward disturbances will be discussed.We attempt to provide a comprehensive analysis of current research by discussing the advantages,challenges,and opportunities brought by deep learning.We hope that deep learning can aid in eliminating factors that hinder the development of EMG-based HMI systems.Furthermore,possible future directions will be presented to pave the way for future research.展开更多
A recent publication by Zhou et al.[1]in Neuron demonstrates that a specific interaction between astrocytes and a subtype of neurons has an influence on complex animal behavior,namely risk assessment.The majority of n...A recent publication by Zhou et al.[1]in Neuron demonstrates that a specific interaction between astrocytes and a subtype of neurons has an influence on complex animal behavior,namely risk assessment.The majority of neuroscientists analyzing the molecular and cellular substrate of behavior focus on neuronal circuits.Glial cells were originally described by Rudolf Virchow and the name glia refers to the Greek word for glue or putty.Thus,glial cells were long thought to represent simply the filling stuff of the brain.This view has changed dramatically in the last decades.The three major types of glial cells of the central nervous system fulfll diverse functions.Oligodendrocytes are the myelinforming cells and it has become evident that they are plastic and are able to influence neuronal connectivity.Microglia are the immune cells of the brain and interact with synapses during development,in plasticity,and very prominently in any disease of the nervous system.展开更多
Hydrogel-based triboelectric nanoge nerator(TENG)has a promising applied prospect in wearable electronic devices.However,its low performance,poor stability,insufficient recyclability and inferior self-healing seriousl...Hydrogel-based triboelectric nanoge nerator(TENG)has a promising applied prospect in wearable electronic devices.However,its low performance,poor stability,insufficient recyclability and inferior self-healing seriously hinder its development.Herein,we report a robust route to a liquid metal(LM)/polyvinyl alcohol(PVA)hydrogel-based TENG(LP-TENG).Owing to the intrinsically liquid feature of conductive LM within the flexible PVA hydrogel,the as-prepared LP-TENG exhibited comprehensiye advantages of adaptability,biocompatibility,outstanding electrical performance,superior stability,recyclability and diverse applications,which were unattainable by traditional systems.Concretely,the LP-TENG delivered appealing open circuit voltage of 250 V,short circuit current of 4μA and transferred charge of 120 nC with high stability,outperforming most advanced TENG systems.The LP-TENG was successfully employed for versatile applications with multifunctionality,including human motion detection,handwriting recognition,energy collection,message transmission and human-machine interaction.This work presents significant prospects for crafting advanced materials and devices in the fields of wearable electronics,flexible skin and smart robots.展开更多
Speech recognition rate will deteriorate greatly in human-machine interaction when the speaker's speech mixes with a bystander's voice. This paper proposes a time-frequency approach for Blind Source Seperation...Speech recognition rate will deteriorate greatly in human-machine interaction when the speaker's speech mixes with a bystander's voice. This paper proposes a time-frequency approach for Blind Source Seperation (BSS) for intelligent Human-Machine Interaction(HMI). Main idea of the algorithm is to simultaneously diagonalize the correlation matrix of the pre-whitened signals at different time delays for every frequency bins in time-frequency domain. The prososed method has two merits: (1) fast convergence speed; (2) high signal to interference ratio of the separated signals. Numerical evaluations are used to compare the performance of the proposed algorithm with two other deconvolution algorithms. An efficient algorithm to resolve permutation ambiguity is also proposed in this paper. The algorithm proposed saves more than 10% of computational time with properly selected parameters and achieves good performances for both simulated convolutive mixtures and real room recorded speeches.展开更多
Teleoperation is of great importance in the area of robotics,especially when people are unavailable in the robot workshop.It provides a way for people to control robots remotely using human intelligence.In this paper,...Teleoperation is of great importance in the area of robotics,especially when people are unavailable in the robot workshop.It provides a way for people to control robots remotely using human intelligence.In this paper,a robotic teleoperation system for precise robotic manipulation is established.The data glove and the 7-degrees of freedom(DOFs)force feedback controller are used for the remote control interaction.The control system and the monitor system are designed for the remote precise manipulation.The monitor system contains an image acquisition system and a human-machine interaction module,and aims to simulate and detect the robot running state.Besides,a visual object tracking algorithm is developed to estimate the states of the dynamic system from noisy observations.The established robotic teleoperation systemis applied to a series of experiments,and high-precision results are obtained,showing the effectiveness of the physical system.展开更多
As the Internet of Things advances,gesture recognition emerges as a prominent domain in human-machine interaction(HMI).However,interactive wearables based on conductive hydrogels for individuals with single-arm functi...As the Internet of Things advances,gesture recognition emerges as a prominent domain in human-machine interaction(HMI).However,interactive wearables based on conductive hydrogels for individuals with single-arm functionality or disabilities remain underexplored.Here,we devised a wearable one-handed keyboard with gesture recognition,employing machine learning algorithms and hydrogel-based mechanical sensors to boost productivity.PCG(PAM/CMC/rGO)hydrogels are composed of polyacrylamide(PAM),sodium carboxymethyl cellulose(CMC),and reduced graphene oxide(rGO),which function as a strain,pressure sensor,and electrode material.The PAM chains offer the gel’s elasticity by covalent cross-linking,while the biocompatible CMC improves the dispersion of rGO and promotes electromechanical properties.Integrating rGO sheets into the polymer matrix facilitates cross-linking and generates supple-mentary conductive pathways,thereby augmenting the gel system’s elasticity,sensitivity,and durability.Our hydrogel sensors include high sensitivity(gage factor(GF)=8.18,395.6%-551.96%)and superior pressure sensing capabilities(Sensitivity(S)=0.3116 kPa^(-1),0-9.82 kPa).Furthermore,we developed a wearable keyboard with up to 98.13%accuracy using convolutional neural networks and a custom data acquisition system.This study establishes the groundwork for creating multifunctional gel sensors for intelligent machines,wearable devices,and brain-computer interfaces.展开更多
Using newly developed methods and software, association mapping was conducted for chromium content and total sugar in tobacco leaf, based on four-omics datasets. Our objective was to collect data on genotype and pheno...Using newly developed methods and software, association mapping was conducted for chromium content and total sugar in tobacco leaf, based on four-omics datasets. Our objective was to collect data on genotype and phenotype for 60 leaf samples at four developmental stages, from three plant architectural positions and for three cultivars that were grown in two locations. Association mapping was conducted to detect genetic variants at quantitative trait SNP(QTS) loci, quantitative trait transcript(QTT) differences,quantitative trait protein(QTP) variability, and quantitative trait metabolite(QTM) changes,which can be summarized as QTX locus variation. The total heritabilities of the four-omics loci for both traits tested were 23.60% for epistasis and 15.26% for treatment interaction.Epistasis and environment × treatment interaction had important impacts on complex traits at all-omics levels. For decreasing chromium content and increasing total sugar in tobacco leaf, six methylated loci can be directly used for marker-assisted selection, and expression of ten QTTs, seven QTPs and six QTMs can be modified by selection or cultivation.展开更多
The inclusion complex of β-cyclodextrin (β-CD) with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains...The inclusion complex of β-cyclodextrin (β-CD) with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2(C42H70O35)·2(CTH5O2Cl)·29(H2O). In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of vip molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar vips.展开更多
A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized b...A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483(4),b = 7.2450(8),c = 27.559(3) ,β = 134.0180(10)°,V = 5525.6(10) 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ(MoKα) = 1.025 mm-1,F(000) = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections(I 2σ(I)).The title complex consists of centrosymmetric dinuclear units [Cu(NIT3Py)2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.展开更多
Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)3(5,5’-dmebipy)(H2O)]2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5’-dmebipy=5,5’-dmethylbipyridine) were synthe...Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)3(5,5’-dmebipy)(H2O)]2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5’-dmebipy=5,5’-dmethylbipyridine) were synthesized and characterized by elemental analysis, infrared spectroscopy and single crystal X-ray diffraction. Findings indicated that complex 3 was a dinuclear molecule, and the center Dy3+ was eight-coordinated. Each dinuclear units could be connected by H bond and halogen-halogen interactions. Luminescent property of complex 2 suggested the typical intense emissions of Eu3+ ions. Thermal analysis showed that the complexes decomposed in three steps: the coordination water was lost firstly then the neutral ligand 5,5’dmebipy was lost and lastly the 2,3-DClBA ligand was lost.展开更多
A new mixed-ligand Mn(II)complex,namely [Mn(bipy)2(Huca)]·5H2O(1,bipy = 2,2'-bipyridine,and H3uca = uracil-5-carboxylic acid)has been prepared and characterized by single-crystal X-ray diffraction,FT-IR ...A new mixed-ligand Mn(II)complex,namely [Mn(bipy)2(Huca)]·5H2O(1,bipy = 2,2'-bipyridine,and H3uca = uracil-5-carboxylic acid)has been prepared and characterized by single-crystal X-ray diffraction,FT-IR spectroscopy and thermogravimetric analysis.It crystallizes in monoclinic,space group C2/c with a = 23.597(8),b = 16.434(5),c = 15.531(6),β = 112.785(6)o,C25H28MnN6O9,Mr = 611.47,V = 5553(3)3,Z = 8,μ = 0.538,Dc = 1.463 g/cm3,F(000)= 2536,R = 0.0441 and wR = 0.1230 for all 5227 observed reflections(I 2σ(I)).The manganese(II)center is surrounded by three bidentate chelating ligands,and it displays a severely distorted octahedral geometry,with cis angles ranging from 72.14(6)to 109.78(6)o.Extensive intermolecular hydrogen bonds link the [Mn(bipy)2(Huca)] monomers and lattice water molecules to yield a three-dimensional supramolecular framework.TGA shows complete removal of all lattice water molecules above 270 ℃.展开更多
1-Picolyl-3-propylbenzimidazolium bromide (LBr) was prepared from benzimida- zole by alkylation with 2-chloromethyl-pyridine in the presence of NaH, followed by quaternization with 1-bromopropane. Ligand LBr was tre...1-Picolyl-3-propylbenzimidazolium bromide (LBr) was prepared from benzimida- zole by alkylation with 2-chloromethyl-pyridine in the presence of NaH, followed by quaternization with 1-bromopropane. Ligand LBr was treated with AgBr in CH2Cl2 to afford a dinuclear silver(I) complex L2Ag2Br4 (1). In complex 1, a 2-D supramolecular layer is formed through two types of π-π stacking interactions. Fluorescent emission spectra of ligand LBr and complex 1 are described.展开更多
A complex,namely[Cu_(4)(L)_(2)(CH_(3)O)_(2)(CH_(3)OH)_(4)(SO_(4))_(2)]SO_(4)·6CH_(3)OH(1)(L=N,N′-bis-(1-(3-ethyl-pyrazin-2-yl)-ethylidene)-hydrazine)has been synthesized and characterized by single-crystal X-ray...A complex,namely[Cu_(4)(L)_(2)(CH_(3)O)_(2)(CH_(3)OH)_(4)(SO_(4))_(2)]SO_(4)·6CH_(3)OH(1)(L=N,N′-bis-(1-(3-ethyl-pyrazin-2-yl)-ethylidene)-hydrazine)has been synthesized and characterized by single-crystal X-ray diffraction,elemental analysis and IR spectroscopy.X-ray diffraction analysis results show that in complex 1,each Cu(Ⅱ)center with a distorted octahedron geometry is coordinated by two N atoms from one pyrazin-2-yl-ethylideneamine subunit,and four O atoms involving one O atom from one neutral methanol,oneμ2-bridged O atom from one methoxy anion,oneμ2-bridged O and one monodentate O atoms from two independent sulfate anions,thus forming an ideal planar four-membered Cu4 core.In addition,the fluorescence spectra indicate that the interaction of complex 1 with DNA is stronger than that of the ligand L.CCDC:1844807,L;1844806,1.展开更多
Three novel rare earth complexes [N(CH 3) 4 ][Ln(NF) 4 ]·6H 2 O(Ln=Nd(III)(1),Sm(III)(2),Ho(III)(3)) were synthesized using hydrothermal method from norfloxacin HNF=1-ethyl-6-fluoro-1,4-dihydro-...Three novel rare earth complexes [N(CH 3) 4 ][Ln(NF) 4 ]·6H 2 O(Ln=Nd(III)(1),Sm(III)(2),Ho(III)(3)) were synthesized using hydrothermal method from norfloxacin HNF=1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid,C 16 H 18 FN 3 O 3),imidazole and rare earth nitrates.The complexes were characterized by elemental analysis,FT-IR,TG-DTG and X-ray single crystal diffraction.Each rare earth ion was eight-coordinated with carboxyl-O atoms and keto-O atoms from norfloxacin.Four of the norfloxacin ions acted as bidentate chelate group took part in the coordination with rare earth ion.The structures of complexes were tetragonal system with space group I4 1 /acd,which were allomerism.The interaction between complex 1 and DNA was studied by electronic absorption spectra and fluorescence spectroscopy.The binding interaction between the complex 1 and bovine serum albumin(BSA) was studied by fluorescence spectroscopy.The complex 1 bound to DNA by the mode of partial intercalation.Complex 1 had a strong ability to quench the fluorescence from BSA.The complex interaction was mainly a static quenching process with BSA together with formation of two binding sites.展开更多
o understand the driving forces leading to mixed-ligand complexes in biologi-cal systenis.ternary complexes of M (ATP(L ̄(2-) type, where M = Cu ̄(2+), Ni ̄(2+) orCo ̄(2+) , and L= pyridine(Py) , 4-picoline, 3, 5-lut...o understand the driving forces leading to mixed-ligand complexes in biologi-cal systenis.ternary complexes of M (ATP(L ̄(2-) type, where M = Cu ̄(2+), Ni ̄(2+) orCo ̄(2+) , and L= pyridine(Py) , 4-picoline, 3, 5-lutidine, isoquinoline (lq) or benzimi-dazole(Bi) in aqueous solution were studied by spectropliotometry, some of them(M=Cu ̄(2+), L = isoquinoline or benzimidazole) were also separately studied hy po-tentiometric pH titration. The results show that an intramolecular stacking interac-tion exists between the heteroaromatic ring of the ligands and the purine moiety ofATP.展开更多
The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structu...The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structure has a T shape geometry in which the CO lies along the C 2 axis of CO 2, with the two C atoms direct contact and R (C...C)=0 3227 nm. The corresponding energies of the most stable structure were calculated by means of MP2, MP4D, MP4DQ, MP4SDTQ, MP4SDQ, CCSD and CCSD(T) methods. The BSSE(basis set superposition error) was eliminated by the Boys Bernardi counterpoise correction(CP) method. According to thermodynamics data, van der Waals complex CO 2...CO can be found at a low temperature and/or a high pressure. There is a little charge transferred between the two interacted subunits. In the most stable structure, CO 2 is the acceptor and CO is the donor.展开更多
Kortweg-de Vries (KdV)-typed equations have been used to describe certain nonlinear phenomena in fluids and plasmas. Generalized complex coupled KdV (GCCKdV) equations are investigated in this paper. Through the d...Kortweg-de Vries (KdV)-typed equations have been used to describe certain nonlinear phenomena in fluids and plasmas. Generalized complex coupled KdV (GCCKdV) equations are investigated in this paper. Through the dependent variable transformations and symbolic computation, GCCKdV equations are transformed into their bilinear forms, based on which the one- and two-soliton solutions are obtained. Through the interactions of two solitons, the regular elastic collision are shown. When the wave numbers are complex, three kinds of solitonie collisions are presented: (i) two solitons merge and separate from each other periodically; (ii) two solitons exhibit the attraction and repulsion nearly twice, and finally separate from each other after such type of interaction; (iii) two solitons are ftuctuant in the central region of the collision. Propagation features of solitons are investigated with the effects of the coefficients in the GCCKdV equations considered. Velocity of soliton increase with the a increasing. Amplitude of v increase with the a increasing and decrease with the β increasing.展开更多
The reaction of 6,7-dicyanodipyridoquinoxaline (DICNQ) with AgNO3 in a 1:1 molar ratio by solution method gave a new complex [Ag(DICNQ)2]NO3 1. Single-crystal X-ray diffraction analysis reveals that the complex c...The reaction of 6,7-dicyanodipyridoquinoxaline (DICNQ) with AgNO3 in a 1:1 molar ratio by solution method gave a new complex [Ag(DICNQ)2]NO3 1. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in the space group Ibca of orthorhombic system with eight formula units in a cell. Crystal data for 1: a = 15.7055(17), b = 18.411(2), c = 20.680(2)A, V = 5979.7(11)A3, Z = 8, C32Hl2AgN13O3, Mr = 734.42, Dc = 1.632 g/cm3, μ= 0.734 mm-1, F(000) = 2928, S = 1.023 and T= 293(2) K. The final R = 0.0659 and wR = 0.1927 for 2118 observed reflections with I 〉 2σ(I), and R = 0.0801 and wR = 0.2196 for all data. The complex builds up a packing structure by π-π stacking interactions and shows a luminescent feature.展开更多
基金supported by the National Key R&D Program of China(No.2023YFC3081200)the National Natural Science Foundation of China(No.42077264)the Scientific Research Project of PowerChina Huadong Engineering Corporation Limited(HDEC-2022-0301).
文摘Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features.
基金supported in part by the National Natural Science Foundation of China(U181321461773369+2 种基金61903360)the Selfplanned Project of the State Key Laboratory of Robotics(2020-Z12)China Postdoctoral Science Foundation funded project(2019M661155)。
文摘Electromyography(EMG)has already been broadly used in human-machine interaction(HMI)applications.Determining how to decode the information inside EMG signals robustly and accurately is a key problem for which we urgently need a solution.Recently,many EMG pattern recognition tasks have been addressed using deep learning methods.In this paper,we analyze recent papers and present a literature review describing the role that deep learning plays in EMG-based HMI.An overview of typical network structures and processing schemes will be provided.Recent progress in typical tasks such as movement classification,joint angle prediction,and force/torque estimation will be introduced.New issues,including multimodal sensing,inter-subject/inter-session,and robustness toward disturbances will be discussed.We attempt to provide a comprehensive analysis of current research by discussing the advantages,challenges,and opportunities brought by deep learning.We hope that deep learning can aid in eliminating factors that hinder the development of EMG-based HMI systems.Furthermore,possible future directions will be presented to pave the way for future research.
基金supported by the Shenzhen Key Laboratory of Neuroimmunomodulation for Neurological Diseases(ZDSYS20220304163558001).
文摘A recent publication by Zhou et al.[1]in Neuron demonstrates that a specific interaction between astrocytes and a subtype of neurons has an influence on complex animal behavior,namely risk assessment.The majority of neuroscientists analyzing the molecular and cellular substrate of behavior focus on neuronal circuits.Glial cells were originally described by Rudolf Virchow and the name glia refers to the Greek word for glue or putty.Thus,glial cells were long thought to represent simply the filling stuff of the brain.This view has changed dramatically in the last decades.The three major types of glial cells of the central nervous system fulfll diverse functions.Oligodendrocytes are the myelinforming cells and it has become evident that they are plastic and are able to influence neuronal connectivity.Microglia are the immune cells of the brain and interact with synapses during development,in plasticity,and very prominently in any disease of the nervous system.
基金financially supported by the Natural Science Foundation of China(Nos.22109120,62104170 and 82202757)Zhejiang Provincial Natural Science Foundation of China(Nos.LQ21B030002 and LY23F040001)。
文摘Hydrogel-based triboelectric nanoge nerator(TENG)has a promising applied prospect in wearable electronic devices.However,its low performance,poor stability,insufficient recyclability and inferior self-healing seriously hinder its development.Herein,we report a robust route to a liquid metal(LM)/polyvinyl alcohol(PVA)hydrogel-based TENG(LP-TENG).Owing to the intrinsically liquid feature of conductive LM within the flexible PVA hydrogel,the as-prepared LP-TENG exhibited comprehensiye advantages of adaptability,biocompatibility,outstanding electrical performance,superior stability,recyclability and diverse applications,which were unattainable by traditional systems.Concretely,the LP-TENG delivered appealing open circuit voltage of 250 V,short circuit current of 4μA and transferred charge of 120 nC with high stability,outperforming most advanced TENG systems.The LP-TENG was successfully employed for versatile applications with multifunctionality,including human motion detection,handwriting recognition,energy collection,message transmission and human-machine interaction.This work presents significant prospects for crafting advanced materials and devices in the fields of wearable electronics,flexible skin and smart robots.
文摘Speech recognition rate will deteriorate greatly in human-machine interaction when the speaker's speech mixes with a bystander's voice. This paper proposes a time-frequency approach for Blind Source Seperation (BSS) for intelligent Human-Machine Interaction(HMI). Main idea of the algorithm is to simultaneously diagonalize the correlation matrix of the pre-whitened signals at different time delays for every frequency bins in time-frequency domain. The prososed method has two merits: (1) fast convergence speed; (2) high signal to interference ratio of the separated signals. Numerical evaluations are used to compare the performance of the proposed algorithm with two other deconvolution algorithms. An efficient algorithm to resolve permutation ambiguity is also proposed in this paper. The algorithm proposed saves more than 10% of computational time with properly selected parameters and achieves good performances for both simulated convolutive mixtures and real room recorded speeches.
基金NSFC-Shenzhen Robotics Research Center Project(No.U2013207)the Beijing Science and Technology Plan Project(No.Z191100008019008)。
文摘Teleoperation is of great importance in the area of robotics,especially when people are unavailable in the robot workshop.It provides a way for people to control robots remotely using human intelligence.In this paper,a robotic teleoperation system for precise robotic manipulation is established.The data glove and the 7-degrees of freedom(DOFs)force feedback controller are used for the remote control interaction.The control system and the monitor system are designed for the remote precise manipulation.The monitor system contains an image acquisition system and a human-machine interaction module,and aims to simulate and detect the robot running state.Besides,a visual object tracking algorithm is developed to estimate the states of the dynamic system from noisy observations.The established robotic teleoperation systemis applied to a series of experiments,and high-precision results are obtained,showing the effectiveness of the physical system.
基金supported by the China Postdoctoral Science Foundation(No.2022BG011)the Fundamental Research Funds for Central Universities(No.2020CDJ-LHZZ-077)+1 种基金the Natural Science Foundation of Chongqing,China(No.c stc2020jcyj-msxmX0397)the Fundamental Research Funds for Central Universities(No.00007717).
文摘As the Internet of Things advances,gesture recognition emerges as a prominent domain in human-machine interaction(HMI).However,interactive wearables based on conductive hydrogels for individuals with single-arm functionality or disabilities remain underexplored.Here,we devised a wearable one-handed keyboard with gesture recognition,employing machine learning algorithms and hydrogel-based mechanical sensors to boost productivity.PCG(PAM/CMC/rGO)hydrogels are composed of polyacrylamide(PAM),sodium carboxymethyl cellulose(CMC),and reduced graphene oxide(rGO),which function as a strain,pressure sensor,and electrode material.The PAM chains offer the gel’s elasticity by covalent cross-linking,while the biocompatible CMC improves the dispersion of rGO and promotes electromechanical properties.Integrating rGO sheets into the polymer matrix facilitates cross-linking and generates supple-mentary conductive pathways,thereby augmenting the gel system’s elasticity,sensitivity,and durability.Our hydrogel sensors include high sensitivity(gage factor(GF)=8.18,395.6%-551.96%)and superior pressure sensing capabilities(Sensitivity(S)=0.3116 kPa^(-1),0-9.82 kPa).Furthermore,we developed a wearable keyboard with up to 98.13%accuracy using convolutional neural networks and a custom data acquisition system.This study establishes the groundwork for creating multifunctional gel sensors for intelligent machines,wearable devices,and brain-computer interfaces.
基金supported by the National Basic Research Program of China (2011CB109306 and 2009CB118404)the Program of Introducing Talents of Discipline to Universities of China ("111" Project, B06014)Research Programs (CNTC-D2011100, CNTC-[2012]146, NY-[2011]3047, QKHRZ [2013] 02)
文摘Using newly developed methods and software, association mapping was conducted for chromium content and total sugar in tobacco leaf, based on four-omics datasets. Our objective was to collect data on genotype and phenotype for 60 leaf samples at four developmental stages, from three plant architectural positions and for three cultivars that were grown in two locations. Association mapping was conducted to detect genetic variants at quantitative trait SNP(QTS) loci, quantitative trait transcript(QTT) differences,quantitative trait protein(QTP) variability, and quantitative trait metabolite(QTM) changes,which can be summarized as QTX locus variation. The total heritabilities of the four-omics loci for both traits tested were 23.60% for epistasis and 15.26% for treatment interaction.Epistasis and environment × treatment interaction had important impacts on complex traits at all-omics levels. For decreasing chromium content and increasing total sugar in tobacco leaf, six methylated loci can be directly used for marker-assisted selection, and expression of ten QTTs, seven QTPs and six QTMs can be modified by selection or cultivation.
基金the financial support from the Natural Science Foundation of Hainan Province(no.808145)Doctoral Foundation of Hainan Normal University(no.103303)
文摘The inclusion complex of β-cyclodextrin (β-CD) with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2(C42H70O35)·2(CTH5O2Cl)·29(H2O). In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of vip molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar vips.
基金supported by the National Natural Science Foundation of China (No. 20901059)the Technological Development Foundation Project of Tianjin Educational Committee (No. 20080503)
文摘A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483(4),b = 7.2450(8),c = 27.559(3) ,β = 134.0180(10)°,V = 5525.6(10) 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ(MoKα) = 1.025 mm-1,F(000) = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections(I 2σ(I)).The title complex consists of centrosymmetric dinuclear units [Cu(NIT3Py)2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.
基金supported by the National Natural Science Foundation of China(21073053,21473049)the Natural Science Foundation of Hebei Province,China(B2016205207)
文摘Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)3(5,5’-dmebipy)(H2O)]2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5’-dmebipy=5,5’-dmethylbipyridine) were synthesized and characterized by elemental analysis, infrared spectroscopy and single crystal X-ray diffraction. Findings indicated that complex 3 was a dinuclear molecule, and the center Dy3+ was eight-coordinated. Each dinuclear units could be connected by H bond and halogen-halogen interactions. Luminescent property of complex 2 suggested the typical intense emissions of Eu3+ ions. Thermal analysis showed that the complexes decomposed in three steps: the coordination water was lost firstly then the neutral ligand 5,5’dmebipy was lost and lastly the 2,3-DClBA ligand was lost.
基金supported by the NNSFC (Nos.20973172 and 21071145)the 973 Program (No.2009CB220009)the NSF of Fujian Province (Nos.2008J0175 and 2007F3112)
文摘A new mixed-ligand Mn(II)complex,namely [Mn(bipy)2(Huca)]·5H2O(1,bipy = 2,2'-bipyridine,and H3uca = uracil-5-carboxylic acid)has been prepared and characterized by single-crystal X-ray diffraction,FT-IR spectroscopy and thermogravimetric analysis.It crystallizes in monoclinic,space group C2/c with a = 23.597(8),b = 16.434(5),c = 15.531(6),β = 112.785(6)o,C25H28MnN6O9,Mr = 611.47,V = 5553(3)3,Z = 8,μ = 0.538,Dc = 1.463 g/cm3,F(000)= 2536,R = 0.0441 and wR = 0.1230 for all 5227 observed reflections(I 2σ(I)).The manganese(II)center is surrounded by three bidentate chelating ligands,and it displays a severely distorted octahedral geometry,with cis angles ranging from 72.14(6)to 109.78(6)o.Extensive intermolecular hydrogen bonds link the [Mn(bipy)2(Huca)] monomers and lattice water molecules to yield a three-dimensional supramolecular framework.TGA shows complete removal of all lattice water molecules above 270 ℃.
基金supported by the National Natural Science Foundation of China (No. 20872111)the Natural Science Foundation of Tianjin (No.11JCZDJC22000)
文摘1-Picolyl-3-propylbenzimidazolium bromide (LBr) was prepared from benzimida- zole by alkylation with 2-chloromethyl-pyridine in the presence of NaH, followed by quaternization with 1-bromopropane. Ligand LBr was treated with AgBr in CH2Cl2 to afford a dinuclear silver(I) complex L2Ag2Br4 (1). In complex 1, a 2-D supramolecular layer is formed through two types of π-π stacking interactions. Fluorescent emission spectra of ligand LBr and complex 1 are described.
文摘A complex,namely[Cu_(4)(L)_(2)(CH_(3)O)_(2)(CH_(3)OH)_(4)(SO_(4))_(2)]SO_(4)·6CH_(3)OH(1)(L=N,N′-bis-(1-(3-ethyl-pyrazin-2-yl)-ethylidene)-hydrazine)has been synthesized and characterized by single-crystal X-ray diffraction,elemental analysis and IR spectroscopy.X-ray diffraction analysis results show that in complex 1,each Cu(Ⅱ)center with a distorted octahedron geometry is coordinated by two N atoms from one pyrazin-2-yl-ethylideneamine subunit,and four O atoms involving one O atom from one neutral methanol,oneμ2-bridged O atom from one methoxy anion,oneμ2-bridged O and one monodentate O atoms from two independent sulfate anions,thus forming an ideal planar four-membered Cu4 core.In addition,the fluorescence spectra indicate that the interaction of complex 1 with DNA is stronger than that of the ligand L.CCDC:1844807,L;1844806,1.
基金supported by National Natural Science Foundation of Zhejiang Province (Y407301)
文摘Three novel rare earth complexes [N(CH 3) 4 ][Ln(NF) 4 ]·6H 2 O(Ln=Nd(III)(1),Sm(III)(2),Ho(III)(3)) were synthesized using hydrothermal method from norfloxacin HNF=1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid,C 16 H 18 FN 3 O 3),imidazole and rare earth nitrates.The complexes were characterized by elemental analysis,FT-IR,TG-DTG and X-ray single crystal diffraction.Each rare earth ion was eight-coordinated with carboxyl-O atoms and keto-O atoms from norfloxacin.Four of the norfloxacin ions acted as bidentate chelate group took part in the coordination with rare earth ion.The structures of complexes were tetragonal system with space group I4 1 /acd,which were allomerism.The interaction between complex 1 and DNA was studied by electronic absorption spectra and fluorescence spectroscopy.The binding interaction between the complex 1 and bovine serum albumin(BSA) was studied by fluorescence spectroscopy.The complex 1 bound to DNA by the mode of partial intercalation.Complex 1 had a strong ability to quench the fluorescence from BSA.The complex interaction was mainly a static quenching process with BSA together with formation of two binding sites.
文摘o understand the driving forces leading to mixed-ligand complexes in biologi-cal systenis.ternary complexes of M (ATP(L ̄(2-) type, where M = Cu ̄(2+), Ni ̄(2+) orCo ̄(2+) , and L= pyridine(Py) , 4-picoline, 3, 5-lutidine, isoquinoline (lq) or benzimi-dazole(Bi) in aqueous solution were studied by spectropliotometry, some of them(M=Cu ̄(2+), L = isoquinoline or benzimidazole) were also separately studied hy po-tentiometric pH titration. The results show that an intramolecular stacking interac-tion exists between the heteroaromatic ring of the ligands and the purine moiety ofATP.
基金Supported by the National Natural Science Foundation of China(No.2 99730 2 2 ) the Foundation for Key Teachers inuniversity of State Ministry of Education of China and the Natural Science Foundation of Shandong Province.
文摘The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structure has a T shape geometry in which the CO lies along the C 2 axis of CO 2, with the two C atoms direct contact and R (C...C)=0 3227 nm. The corresponding energies of the most stable structure were calculated by means of MP2, MP4D, MP4DQ, MP4SDTQ, MP4SDQ, CCSD and CCSD(T) methods. The BSSE(basis set superposition error) was eliminated by the Boys Bernardi counterpoise correction(CP) method. According to thermodynamics data, van der Waals complex CO 2...CO can be found at a low temperature and/or a high pressure. There is a little charge transferred between the two interacted subunits. In the most stable structure, CO 2 is the acceptor and CO is the donor.
基金*Supported by the National Natural Science Foundation of China under Grant No. 60772023, by the Open Fund of the State Key Laboratory of Software Development Environment under Grant No. SKLSDE-07-001, Beijing University of Aeronautics and Astronautics, by the National Basic Research Program of China (973 Program) under Grant No. 2005CB321901, and by the Specialized Research Fund for the Doctoral Program of Higher Education under Grant Nos. 20060006024 and 200800130006, Chinese Ministry of Education.
文摘Kortweg-de Vries (KdV)-typed equations have been used to describe certain nonlinear phenomena in fluids and plasmas. Generalized complex coupled KdV (GCCKdV) equations are investigated in this paper. Through the dependent variable transformations and symbolic computation, GCCKdV equations are transformed into their bilinear forms, based on which the one- and two-soliton solutions are obtained. Through the interactions of two solitons, the regular elastic collision are shown. When the wave numbers are complex, three kinds of solitonie collisions are presented: (i) two solitons merge and separate from each other periodically; (ii) two solitons exhibit the attraction and repulsion nearly twice, and finally separate from each other after such type of interaction; (iii) two solitons are ftuctuant in the central region of the collision. Propagation features of solitons are investigated with the effects of the coefficients in the GCCKdV equations considered. Velocity of soliton increase with the a increasing. Amplitude of v increase with the a increasing and decrease with the β increasing.
基金supported by NNSFC (20701037)a Key Project from the CAS (KJCX2-YW-H01)the NSF of Fujian Province (E0510029)
文摘The reaction of 6,7-dicyanodipyridoquinoxaline (DICNQ) with AgNO3 in a 1:1 molar ratio by solution method gave a new complex [Ag(DICNQ)2]NO3 1. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in the space group Ibca of orthorhombic system with eight formula units in a cell. Crystal data for 1: a = 15.7055(17), b = 18.411(2), c = 20.680(2)A, V = 5979.7(11)A3, Z = 8, C32Hl2AgN13O3, Mr = 734.42, Dc = 1.632 g/cm3, μ= 0.734 mm-1, F(000) = 2928, S = 1.023 and T= 293(2) K. The final R = 0.0659 and wR = 0.1927 for 2118 observed reflections with I 〉 2σ(I), and R = 0.0801 and wR = 0.2196 for all data. The complex builds up a packing structure by π-π stacking interactions and shows a luminescent feature.