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Carrier Envelope Phase Effect of a Long Duration Pulse in the Low Frequency Region

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Chinese Physics Letters 2014年第4期31卷 37-40页

作者： ZHAO xi yanG Yu-Jun LIU Xue-Shen WANG bing-bing Institute of Atomic and Molecular Physics Jilin University Changchun 130012 Laboratory of Optical Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080

Using the characteristic of small energy difference between two high Rydberg states, we theoretically investigate the carrier envelope phase （CEP） effect in a bound-bound transition of an atom in a low-frequency long laser pulse with tens of optical cycles. Particularly, we first prepare a Rydberg state of a hydrogen-like atom by a laser field with the resonant frequency between this state and the ground state. Then by using a low-frequency long laser pulse interacting with this Rydberg atom, we calculate the population of another Rydberg state nearby this Rydberg state at the end of the laser pulse and find that the population changes dramatically with the CEP of the low-frequency pulse. This CEP effect is attributed to the interference between the positive-frequency and negative-frequency components in one-photon transition. These results may provide a method to measure the CEP value of a long laser pulse with low frequency.

关键词： Region Carrier characteristic

Attitude Control of Rigid Body with Inertia Uncertainty and Saturation Input

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Tsinghua Science and Technology 2017年第1期22卷 83-91页

作者： xi Ma Fuchun Sun Hongbo Li bing He Department of Computer Science and Technology Tsinghua UniversityState Key Lab of Intelligent Technology and Systemsand Tsinghua National Laboratory for Information Scienceand Technology (TNList) Department of Aerospace Engineering High-Tech Institute of Xi’an

In this paper, the attitude control problem of rigid body is addressed with considering inertia uncertainty,bounded time-varying disturbances, angular velocity-free measurement, and unknown non-symmetric saturation input. Using a mathematical transformation, the effects of bounded time-varying disturbances, uncertain inertia,and saturation input are combined as total disturbances. A novel finite-time observer is designed to estimate the unknown angular velocity and the total disturbances. For attitude control, an observer-based sliding-mode control protocol is proposed to force the system state convergence to the desired sliding-mode surface; the finite-time stability is guaranteed via Lyapunov theory analysis. Finally, a numerical simulation is presented to illustrate the effective performance of the proposed sliding-mode control protocol.

关键词： attitude control inertial uncertainty angular velocity-free measurement saturation input finite-time observer sliding-mode control

Pertussis toxin modulation of sodium channels in the central neurons of cyhalothrin-resistant and cyhalothrinsusceptible cotton bollworm, Helicoverpa armigera

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Insect Science 2007年第2期14卷 107-115页

作者： QIANG ZHAO DE-LING KONG bing-JUN HE yan-QIANG LIU xiAN-LIN FAN AN-xi LIU Key Laboratory of Bioactive Materials Ministry of Education College of Life Sciences Nankai University Tianjin Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing China

Pertussis toxin （FIX） inhibits the activation of the α-subunit of the inhibitory heterotrimeric G-proteins （Cαi/o） and modulates voltage-gated sodium channels, which may be one of the primary targets of pyrethroids. To investigate the potential mechanisms of agricultural pests resistance to pyrethroid insecticides, we examined the modulations by PTX on sodium channels in the central neurons of the 3rd-4th instar larvae of cyhalothrin-resistant （Cy-R） and cyhaiothrin-susceptible （Cy-S） Helicoverpa armigera by the whole-cell patch-clamp technique. The isolated neurons were cultured for 12-16 h in an improved L15 insect culture medium with or without PTX （400 ng/mL）. The results showed that both the Cy-R and Cy-S sodium channels exhibited fast kinetics and tetrodotoxin （TTX） sensitivity. The Cy-R sodium channels exhibited not only altered gating properties, including a 8.88-mV right shift in voltage-dependent activation （V0.5act） and a 6.54-mV right shift in voltage-dependent inactivation （V0.5inact）, but also a reduced peak in sodium channel density （Ⅰdensity）（55.2% of that in Cy-S neurons）. Cy-R sodium channels also showed low excitability, as evidenced by right shift of activation potential （Ⅴacti） by 5-10 mV and peak potential （Ⅴpcak） by 20 mV. FIX exerted significant effects on Cy-S sodium channels, reducing sodium channel density by 70.04%, right shifting V0.5act by 14.41 mV and V0.5inact by 9. 38 mV. It did not cause any significant changes of the parameters mentioned above in the Cy-R sodium channels. The activation time （Tpeak） from latency to peak at peak voltage and the fast inactivation time constant （τinact） in both Cy-S and Cy-R neurons were not affected. The results suggest that cotton bollworm resistant to pyrethroid insecticides involves not only mutations and allosteric alterations of voltage-gated sodium channels, but also might implicate perturbation of PTX-sensitive Gαi/o-COupled signaling Wansduction pathways.

关键词： cyhalothrin G proteins Helicoverpa armigera insecticide resistant neuron pertussis toxin sodium channels whole-cell patch-clamp technique

Numerical analysis of modal tomography for solar multi-conjugate adaptive optics

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Research in Astronomy and Astrophysics 2012年第4期12卷 465-471页

作者： bing Dong De-Qing Ren xi Zhang Physics ＆ Astronomy Department California State University Northridge CA 91330-8268 USA National Astronomical Observatories/Nanjing Institute of Astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China

Multi-conjugate adaptive optics （MCAO） can considerably extend the cor- rected field of view with respect to classical adaptive optics, which will benefit solar observation in many aspects. In solar MCAO, the Sun structure is utilized to provide multiple guide stars and a modal tomography approach is adopted to implement three- dimensional wavefront restorations. The principle of modal tomography is briefly re- viewed and a numerical simulation model is built with three equivalent turbulent lay- ers and a different number of guide stars. Our simulation results show that at least six guide stars are required for an accurate wavefront reconstruction in the case of three layers, and only three guide stars are needed in the two layer case. Finally, eigen- mode analysis results are given to reveal the singular modes that cannot be precisely retrieved in the tomography process.

关键词： instrumentation: multi-conjugate adaptive optics -- tomography

Mesenchymal stem cell-derived exosomes: A novel and potential remedy for cutaneous wound healing and regeneration

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World Journal of Stem Cells 2022年第5期14卷 318-329页

作者： Jia-Chen Hu Chen-xi Zheng bing-Dong Sui Wen-Jia Liu yan Jin Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi International Joint Research Center for Oral Diseases Center for Tissue EngineeringSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina National and Local Joint Engineering Research Center of Biodiagnosis and Biotherapy Precision Medicine InstituteInstitute for Stem Cell and Regenerative MedicineThe Second Affiliated HospitalXi’an Jiaotong UniversityXi’an 710032Shaanxi ProvinceChina

Poor healing of cutaneous wounds is a common medical problem in the field of *** to the intricate pathophysiological processes of wound healing,the use of conventional treatment methods,such as chemical molecule drugs and traditional dressings,have been unable to achieve satisfactory *** recent years,explicit evidence suggests that mesenchymal stem cells(MSCs)have great therapeutic potentials on skin wound healing and ***,the direct application of MSCs still faces many challenges and ***,exosomes as cell-secreted granular vesicles with a lipid bilayer membrane structure and containing specific components from the source cells may emerge to be excellent substitutes for *** derived from MSCs(MSC-exosomes)have been demonstrated to be beneficial for cutaneous wound healing and accelerate the process through a variety of *** mechanisms include alleviating inflammation,promoting vascularization,and promoting proliferation and migration of epithelial cells and ***,the application of MSC-exosomes may be a promising alternative to cell therapy in the treatment of cutaneous wounds and could promote wound healing through multiple mechanisms *** review will provide an overview of the role and the mechanisms of MSC-derived exosomes in cutaneous wound healing,and elaborate the potentials and future perspectives of MSC-exosomes application in clinical practice.

关键词： Mesenchymal stem cells Extracellular vesicles Exosomes Wound healing Skin regeneration

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

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Journal of Energy Chemistry 2025年第1期100卷 533-543页

作者： Zewen Liu Zhen Wu Hao Wang Xudong Zhang Yuanzhen Chen Yongning Liu Shengwu Guo Shenghua Chen yanli Nan yan Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp Ltd Network Information Center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558Co0.074O2（L1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li1.2Ni0.13Mn0.54Co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

关键词： Ice

Diffusion tensor imaging of the brain in patients with Alzheimer's disease and cerebrovascular lesions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第4期8卷 242-247页

作者： CHEN Shao-qiong KANG Zhuang HU xi-quan HU bing ZOU yan Department of Radiology the Third Affiliated Hospital Sun Yat-Sen University Guangzhou 510630 China Department of Rehabilitation the Third Affiliated Hospital Sun Yat-Sen University Guangzhou 5 10630 China

Background:Recent autopsy study showed a high incidence of cerebrovascular lesions in Alzheimer's disease(AD).To assess the impact of cerebrovascular pathology in AD,we used diffusion tensor imaging(DTI) to study AD patients with and without cerebrovascular *** and Methods:Conventional and DTI scans were obtained from 10 patients with probable AD,10 AD/V patients(probable AD with cerebrovascular lesions) and ten normal *** diffusivity(D) and fractional anisotropy(FA) values of some structures involved with AD pathology were ***:D value was higher in AD patients than in controls in hippocampus and the cingulate *** AD/V patients,increased D value was found in the same structures and also in the thalamus and basal ganglia compared to *** was a significant difference of D value between AD and AD/V *** value reduced in the white matter of left inferior temporal gyrus and in the bilateral middle cingulate gyrus in patients with AD/V compared with *** MMSE(mini-mental state examination) score significantly correlated with FA value in the right hippocampus(r=0.639,P<0.019),in the right anterior cingulate gyrus(r=0.587,P<0.035) and in left parahippocampal gyrus(r=0.559,P<0.047).Conclusion:Cerebrovascular pathology had stronger impact on the D value than the AD pathology alone *** D value in thalamic and basal ganglia may contribute to cognitive decline in AD/V *** FA values in AD/V patients may indicate that cerebrovascular pathology induced more severe white matter damage than the AD pathology alone did.

关键词： Diffusion tensor imaging (DTI) Alzheimer's disease (AD) Cerebrovascular Magnetic resonance imaging (MRI)

An AND-type 1T-FeFET array with robust write and read operations

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Science China(Information Sciences) 2025年

作者： Jiacheng XU Jiayi ZHAO Hongrui ZHANG Haoji QIAN Jiani GU Bowen CHEN Gaobo LIN Rongzong SHEN xinda SONG Huan LIU Yian DING Minglei MA Miaomiao ZHANG xiao YU bing CHEN Ran CHENG Gaobo XU Huaxiang YIN yan LIU Jiajia CHEN Chengji JIN Genquan HAN Hangzhou Institute of Technology and School of Microelectronics Xidian University Zhejiang Lab College of Integrated Circuits Zhejiang University Key Laboratory of Microelectronics Devices and Integrated Technology Institute of MicroelectronicsChinese Academy of Sciences

HfO2-based ferroelectric field-effect transistor （FeF ET） has become a promising solution for next-generation embedded non-volatile memory （NVM） owing to its complementary metal-oxide-semiconductor （CMOS） compatibility,small footprint, high performance, and non-destructive readout [1]. Recent research of HfO2-based FeF ET has focused on the device operation mechanisms as well as reliability issues such as the interplay between polarization switching and charge trapping/detrapping [2], read-after-write latency [3] and endurance degradation [4]. It has been demonstrated that endurance higher than 1010cycles with negligible read-after-write latency is possible if the gate stack of FeF ET is well engineered [5].

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SYMMETRICAL SISF IN DEFORMED Ni_3Al AND ITS FORMATION MECHANISM

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 76-81页

作者： yan Wen xi′an Institute of Technology,xi′an,China xi'an Inst of Technology Xi'an China

The symmetrical superlattice intrinsic stacking faults(SISFs)formed on {111} planes are the predominant crystal defects in polycrystalline Ni_3AI after slight deformation at room temper- *** formation of this kind of SISF is resulted from the dipoles which are distributed on the neighboring {111} planes after reorientation,dissociation and annihilation under applied stress.

关键词： deformed Ni_3Al symmetrical stacking fault formation mechanism