BACKGROUND： Low-frequency repetitive transcranial magnetic stimulation （rTMS） has been shown to significantly reduce epileptiform discharges and control clinical seizures in intractable epilepsy patients. The locat...BACKGROUND： Low-frequency repetitive transcranial magnetic stimulation （rTMS） has been shown to significantly reduce epileptiform discharges and control clinical seizures in intractable epilepsy patients. The location of epileptic foci and magnetic stimulation sites remain uncertain. The effects of rTMS on electroencephalogram and seizure remain unclear in epileptic patients following dipole source localization. OBJECTIVE： To investigate the effects of low-frequency rTMS on electroencephalogram and seizure in temporal lobe epilepsy patients after dipole source localization. DESIGN, TIME AND SETTING： The randomized, controlled study was performed at the outpatient clinic Department of Neurology, Hospital Affiliated to North Sichuan Medical College from December 2003 to February 2007. PARTICIPANTS： A total of 30 temporal lobe epilepsy patients, comprising 19 males and 11 females, aged 1749 years, presented with epileptiform discharges and were enrolled for this study. Disease course ranged between 1-6 years, with 1-5 seizures per month. Imaging examinations revealed 11 patients with structural changes in the brain. The patients were randomly and equally assigned into drug treatment and transcranial magnetic stimulation （TMS） groups. METHODS： Patients in the drug treatment group were orally treated with carbamazepine. Patients in the TMS group received oral carbamazepine treatment of and TMS. A Maglite-r25 magnetic stimulator （Dantec Dynamics, Denmark） was used to stimulate epileptic foci in the temporal lobe following electroencephalogram dipole localization （1 Hz, 90% threshold intensity, at a stimulation frequency of 500 times, once a day, for 7 days）. MAIN OUTCOME MEASURES： At 30 days after TMS, seizure frequency and rate of epileptiform discharges were observed in patients from both groups. Therapeutic safety was investigated during treatment. RESULTS： Within 30 days of treatment, there were no significant differences in seizure frequency between the TMS group （1.5 ± 0.3） seizures and the drug treatment group [（1.9± 0.4） seizures] （P 〉 0.05）. The rate of epileptiform discharges [27% （4/15）] was significantly less in the TMS group than in the drug treatment group [73% （11/15）] （P 〈 0.05）. During TMS, five patients suffered from transient mild headache, but were completely relieved within 2 hours. CONCLUSION： Low-frequency rTMS exhibited inhibitory effects on epileptiform discharges over a short period of time, and decreased seizure frequency to some degree. Results from the present study suggested that low-frequency rTMS is safe.展开更多
Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely orien...Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely oriented.Using NbOCl_(2) monolayer with competing ferroelectric(FE)and antiferroelectric(AFE)phases as a 2D material platform,we demonstrate the emergence of intrinsic antiferroelectricity in NbOCl_(2) monolayer under experimentally accessible shear strain,along with new functionality associated with electric field-induced AFE-to-FE phase transition.Specifically,the complex configuration space accommodating FE and AFE phases,polarization switching kinetics,and finite temperature thermodynamic properties of 2D NbOCl_(2) are all accurately predicted by large-scale molecular dynamics simulations based on deep learning interatomic potential model.Moreover,room temperature stable antiferroelectricity with low polarization switching barrier and one-dimensional collinear polarization arrangement is predicted in shear-deformed NbOCl_(2) monolayer.The transition from AFE to FE phase in 2D NbOCl_(2) can be triggered by a low critical electric field,leading to a double polarization–electric(P–E)loop with small hysteresis.A new type of optoelectronic device composed of AFE-NbOCl_(2) is proposed,enabling electric“writing”and nonlinear optical“reading”logical operation with fast operation speed and low power consumption.展开更多
Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the l...Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the local charge effect of the targeted spot which is normally smeared out in conventional average work function measurements. Chloroaluminum phthalocyanine （CIA1Pc）, an important optoelectronic molecule with a permanent dipole moment pointing from the Pc ring to the ending CI atom, adsorbed on Au（111） in either Cl-up or Cl-down configuration. Scanning tunneling microscopy/spectroscopy measurements revealed that at the centers of Cl-up and CI-down molecules, the local work functions changed oppositely with respect to the Au（111） substrate. At their Pc lobes, however, the local work functions unanimously increased due to charging effect of the indole lobes in the CIAIPc molecule.展开更多
The wavelength dependence of electron localization of H2^＋ and its isotopomers in the ultraviolet pump-probe scheme is investigated by numerically solving the time-dependent Schrodinger equation. By combining with a ...The wavelength dependence of electron localization of H2^＋ and its isotopomers in the ultraviolet pump-probe scheme is investigated by numerically solving the time-dependent Schrodinger equation. By combining with a semiclassical method,an effective analytical formula expressed in the adiabatic representation is established to describe the localization probability with several zero crossings. A stable zone with respect to the laser intensity and carrier envelope phase is found at a relatively long probe wavelength. Finally, the critical probe wavelengths to reach at the stable zone are derived by using the three-dimensional model. Slower nuclear motion of heavier isotopomers leads to a longer critical wavelength.展开更多
A thermally tunable terahertz metamaterial absorber(MA) with InS b embedded in a metal-dielectric-metal structure is proposed. The transmission and tuning properties of the proposed metamaterial absorber are analyzed ...A thermally tunable terahertz metamaterial absorber(MA) with InS b embedded in a metal-dielectric-metal structure is proposed. The transmission and tuning properties of the proposed metamaterial absorber are analyzed for the temperature ranging from 160 K to 350 K. The simulated results show that the maximum absorption of the absorber is nearly 99.8% at a full-width at half-maximum(FWHM) of 38 GHz, and the absorption frequency can be dynamically tuned from 0.82 THz to 1.02 THz.展开更多
The surface charge properties and local dipole moment of terminal groups have a significant impact on molecular packing and aggregation performance of non-fullerene acceptors(NFAs)for organic solar cells(OSCs).Here,we...The surface charge properties and local dipole moment of terminal groups have a significant impact on molecular packing and aggregation performance of non-fullerene acceptors(NFAs)for organic solar cells(OSCs).Here,we utilize the interactions between different building blocks within the molecule to regulate the dipole asymmetry of terminal groups by introducing asymmetric inner side chains.Three NFAs,BTA80,BTA81 and BTA82 are designed and synthesized with different substitutions of benzotriazole(BTA)-based inner side chains.The asymmetric introduction of BTA-based inner side chains can modulate the asymmetric surface electrostatic potential and local dipole moments of the terminal groups through the interactions between BTA and the terminal groups,which in turn modifies the molecular orientation and enhances molecular packing.As the result,D18:BTA82-based OSCs achieve the champion power conversion efficiency(PCE)of 17.70%compared to D18:BTA80 and D18:BTA81-based devices with PCE of 16.06%and 16.65%,respectively.Moreover,by introducing the BTA82 as the third component into D18:L8-BO system,the ternary device exhibits a significant improved PCE of 19.60%compared to the device based D18:L8-BO(PCE of 18.73%).This work provides a novel insight into the design of asymmetric NFAs for high performance OSCs.展开更多
Most fish and aquatic amphibians use the lateral line system,consisting of arrays of hair-like neuromasts,as an important sensory organ for prey/predator detection,communication,and navigation.In this paper a novel bi...Most fish and aquatic amphibians use the lateral line system,consisting of arrays of hair-like neuromasts,as an important sensory organ for prey/predator detection,communication,and navigation.In this paper a novel bio-inspired artificial lateral line system is proposed for underwater robots and vehicles by exploiting the inherent sensing capability of ionic polymer-metal composites(IPMCs).Analogous to its biological counterpart,the IPMC-based lateral line processes the sensor signals through a neural network.The effectiveness of the proposed lateral line is validated experimentally in the localization of a dipole source(vibrating sphere)underwater.In particular,as a proof of concept,a prototype with body length(BL)of 10 cm,comprising six millimeter-scale IPMC sensors,is constructed and tested.Experimental results have shown that the IPMC-based lateral line can localize the source from 1-2 BLs away,with a maximum localization error of 0.3 cm,when the data for training the neural network are collected from a grid of 2 cm by 2 cm lattices.The effect of the number of sensors on the localization accuracy has also been examined.展开更多
Two co-crystalline compounds containing telluric acid and iodate,namely AIO_(3)·H_(6)TeO_(6)(A=Rb^(+),NH_(4)^(+)),were investigated as potential nonlinear optical materials.They crystallize into isostructural and...Two co-crystalline compounds containing telluric acid and iodate,namely AIO_(3)·H_(6)TeO_(6)(A=Rb^(+),NH_(4)^(+)),were investigated as potential nonlinear optical materials.They crystallize into isostructural and consist of isolated[IO_(3)]group and[H_(6)TeO_(6)]molecule linked by hydrogen bonds and charge interactions of Rb^(+)/NH_(4)^(+).They show phase-matching second harmonic generation responses with moderate intensity of 1.2×KDP(Rb^(+))and 1.1×KDP(NH_(4)^(+)).They also possess large optical band gaps over 4.25 eV and can be easily grown from aqueous so-lutions.The local dipole moment calculations based on the structures of AIO_(3)·H_(6)TeO_(6)(A=K+,Rb^(+),NH_(4)^(+))series of compounds indicate that the change of A+cation in their structural frame causes a slight change in the arrangement directions of[IO_(3)]and[Te(OH)_(6)]groups,and further induces their SHG responses of different in-tensities at the macroscopic level.展开更多
基金the Youth Foundation Program of Sichuan Province,No.04ZQ026-010
文摘BACKGROUND： Low-frequency repetitive transcranial magnetic stimulation （rTMS） has been shown to significantly reduce epileptiform discharges and control clinical seizures in intractable epilepsy patients. The location of epileptic foci and magnetic stimulation sites remain uncertain. The effects of rTMS on electroencephalogram and seizure remain unclear in epileptic patients following dipole source localization. OBJECTIVE： To investigate the effects of low-frequency rTMS on electroencephalogram and seizure in temporal lobe epilepsy patients after dipole source localization. DESIGN, TIME AND SETTING： The randomized, controlled study was performed at the outpatient clinic Department of Neurology, Hospital Affiliated to North Sichuan Medical College from December 2003 to February 2007. PARTICIPANTS： A total of 30 temporal lobe epilepsy patients, comprising 19 males and 11 females, aged 1749 years, presented with epileptiform discharges and were enrolled for this study. Disease course ranged between 1-6 years, with 1-5 seizures per month. Imaging examinations revealed 11 patients with structural changes in the brain. The patients were randomly and equally assigned into drug treatment and transcranial magnetic stimulation （TMS） groups. METHODS： Patients in the drug treatment group were orally treated with carbamazepine. Patients in the TMS group received oral carbamazepine treatment of and TMS. A Maglite-r25 magnetic stimulator （Dantec Dynamics, Denmark） was used to stimulate epileptic foci in the temporal lobe following electroencephalogram dipole localization （1 Hz, 90% threshold intensity, at a stimulation frequency of 500 times, once a day, for 7 days）. MAIN OUTCOME MEASURES： At 30 days after TMS, seizure frequency and rate of epileptiform discharges were observed in patients from both groups. Therapeutic safety was investigated during treatment. RESULTS： Within 30 days of treatment, there were no significant differences in seizure frequency between the TMS group （1.5 ± 0.3） seizures and the drug treatment group [（1.9± 0.4） seizures] （P 〉 0.05）. The rate of epileptiform discharges [27% （4/15）] was significantly less in the TMS group than in the drug treatment group [73% （11/15）] （P 〈 0.05）. During TMS, five patients suffered from transient mild headache, but were completely relieved within 2 hours. CONCLUSION： Low-frequency rTMS exhibited inhibitory effects on epileptiform discharges over a short period of time, and decreased seizure frequency to some degree. Results from the present study suggested that low-frequency rTMS is safe.
基金supported by the National Natural Science Foundation of China (Grant No.11574244 for G.Y.G.)the XJTU Research Fund for AI Science (Grant No.2025YXYC011 for G.Y.G.)the Hong Kong Global STEM Professorship Scheme (for X.C.Z.)。
文摘Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely oriented.Using NbOCl_(2) monolayer with competing ferroelectric(FE)and antiferroelectric(AFE)phases as a 2D material platform,we demonstrate the emergence of intrinsic antiferroelectricity in NbOCl_(2) monolayer under experimentally accessible shear strain,along with new functionality associated with electric field-induced AFE-to-FE phase transition.Specifically,the complex configuration space accommodating FE and AFE phases,polarization switching kinetics,and finite temperature thermodynamic properties of 2D NbOCl_(2) are all accurately predicted by large-scale molecular dynamics simulations based on deep learning interatomic potential model.Moreover,room temperature stable antiferroelectricity with low polarization switching barrier and one-dimensional collinear polarization arrangement is predicted in shear-deformed NbOCl_(2) monolayer.The transition from AFE to FE phase in 2D NbOCl_(2) can be triggered by a low critical electric field,leading to a double polarization–electric(P–E)loop with small hysteresis.A new type of optoelectronic device composed of AFE-NbOCl_(2) is proposed,enabling electric“writing”and nonlinear optical“reading”logical operation with fast operation speed and low power consumption.
基金supported by National Natural Science Foundation of China(Nos. 91527303, 21333001,21373020, 61321001)MOST(Nos.2013CB933404,2014CB239302),China
文摘Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the local charge effect of the targeted spot which is normally smeared out in conventional average work function measurements. Chloroaluminum phthalocyanine （CIA1Pc）, an important optoelectronic molecule with a permanent dipole moment pointing from the Pc ring to the ending CI atom, adsorbed on Au（111） in either Cl-up or Cl-down configuration. Scanning tunneling microscopy/spectroscopy measurements revealed that at the centers of Cl-up and CI-down molecules, the local work functions changed oppositely with respect to the Au（111） substrate. At their Pc lobes, however, the local work functions unanimously increased due to charging effect of the indole lobes in the CIAIPc molecule.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11404153,11135002,11475076,and 11405077)the Fundamental Research Funds for the Central Universities of China(Grants Nos.lzujbky-2016-29,lzujbky-2016-31,and lzujbky-2016-209)
文摘The wavelength dependence of electron localization of H2^＋ and its isotopomers in the ultraviolet pump-probe scheme is investigated by numerically solving the time-dependent Schrodinger equation. By combining with a semiclassical method,an effective analytical formula expressed in the adiabatic representation is established to describe the localization probability with several zero crossings. A stable zone with respect to the laser intensity and carrier envelope phase is found at a relatively long probe wavelength. Finally, the critical probe wavelengths to reach at the stable zone are derived by using the three-dimensional model. Slower nuclear motion of heavier isotopomers leads to a longer critical wavelength.
基金supported by the National Basic Research Program of China(No.2014CB339800)the National High Technology Research and Development Program of China(No.2011AA010205)the National Natural Science Foundation of China(Nos.61171027 and 10904076)
文摘A thermally tunable terahertz metamaterial absorber(MA) with InS b embedded in a metal-dielectric-metal structure is proposed. The transmission and tuning properties of the proposed metamaterial absorber are analyzed for the temperature ranging from 160 K to 350 K. The simulated results show that the maximum absorption of the absorber is nearly 99.8% at a full-width at half-maximum(FWHM) of 38 GHz, and the absorption frequency can be dynamically tuned from 0.82 THz to 1.02 THz.
基金support from the National Natural Science Foundation of China(52303259,52373176).
文摘The surface charge properties and local dipole moment of terminal groups have a significant impact on molecular packing and aggregation performance of non-fullerene acceptors(NFAs)for organic solar cells(OSCs).Here,we utilize the interactions between different building blocks within the molecule to regulate the dipole asymmetry of terminal groups by introducing asymmetric inner side chains.Three NFAs,BTA80,BTA81 and BTA82 are designed and synthesized with different substitutions of benzotriazole(BTA)-based inner side chains.The asymmetric introduction of BTA-based inner side chains can modulate the asymmetric surface electrostatic potential and local dipole moments of the terminal groups through the interactions between BTA and the terminal groups,which in turn modifies the molecular orientation and enhances molecular packing.As the result,D18:BTA82-based OSCs achieve the champion power conversion efficiency(PCE)of 17.70%compared to D18:BTA80 and D18:BTA81-based devices with PCE of 16.06%and 16.65%,respectively.Moreover,by introducing the BTA82 as the third component into D18:L8-BO system,the ternary device exhibits a significant improved PCE of 19.60%compared to the device based D18:L8-BO(PCE of 18.73%).This work provides a novel insight into the design of asymmetric NFAs for high performance OSCs.
基金supported in part by the National Science Foundation(ECCS 0547131,CCF 0820220,IIS 0916720)the Office of Naval Research(Grant N000140810640).
文摘Most fish and aquatic amphibians use the lateral line system,consisting of arrays of hair-like neuromasts,as an important sensory organ for prey/predator detection,communication,and navigation.In this paper a novel bio-inspired artificial lateral line system is proposed for underwater robots and vehicles by exploiting the inherent sensing capability of ionic polymer-metal composites(IPMCs).Analogous to its biological counterpart,the IPMC-based lateral line processes the sensor signals through a neural network.The effectiveness of the proposed lateral line is validated experimentally in the localization of a dipole source(vibrating sphere)underwater.In particular,as a proof of concept,a prototype with body length(BL)of 10 cm,comprising six millimeter-scale IPMC sensors,is constructed and tested.Experimental results have shown that the IPMC-based lateral line can localize the source from 1-2 BLs away,with a maximum localization error of 0.3 cm,when the data for training the neural network are collected from a grid of 2 cm by 2 cm lattices.The effect of the number of sensors on the localization accuracy has also been examined.
基金support from the National Natural Science Foundation of China(Grant No.22105046)the Natural Science Foundation of Guangxi Province(No.2022GXNSFBA035484)the Shanghai Pujiang Program(20PJ1412900).
文摘Two co-crystalline compounds containing telluric acid and iodate,namely AIO_(3)·H_(6)TeO_(6)(A=Rb^(+),NH_(4)^(+)),were investigated as potential nonlinear optical materials.They crystallize into isostructural and consist of isolated[IO_(3)]group and[H_(6)TeO_(6)]molecule linked by hydrogen bonds and charge interactions of Rb^(+)/NH_(4)^(+).They show phase-matching second harmonic generation responses with moderate intensity of 1.2×KDP(Rb^(+))and 1.1×KDP(NH_(4)^(+)).They also possess large optical band gaps over 4.25 eV and can be easily grown from aqueous so-lutions.The local dipole moment calculations based on the structures of AIO_(3)·H_(6)TeO_(6)(A=K+,Rb^(+),NH_(4)^(+))series of compounds indicate that the change of A+cation in their structural frame causes a slight change in the arrangement directions of[IO_(3)]and[Te(OH)_(6)]groups,and further induces their SHG responses of different in-tensities at the macroscopic level.
