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Normal Form for Families of Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1199-1216页

作者： zhi guo WANG Department of Mathematics Nanjing University School of Mathematical Sciences Suzhou University

We consider perturbations of integrable Hamiltonian systems in the neighborhood of normally parabolic invariant tori. Using the techniques of KAM-theory we prove that there exists a canonical transformation that puts the Hamiltonian in normal form up to a remainder of weighted order 2d ＋ 1. And some dynamical consequences are obtained.

关键词： KAM lower dimensional tori normal form resonant torus

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

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Neural Regeneration Research 2025年第9期20卷 2655-2666页

作者： Yiyang Qin Wenzhen Zhu Tingting guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-Jiang Li Su Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong–HongKong–Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto *** mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy *** aggregates alter protein-protein interactions and compromise transcriptional *** this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic *** n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor *** down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor *** findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

关键词： androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model neurodegeneration neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor

Side-chain engineering of high-efficiency conjugated polymer photovoltaic materials

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Science China Chemistry 2015年第2期58卷 192-209页

作者： zhi-guo Zhang Yongfang Li Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Laboratory of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials Science Soochow University

In recent years,conjugated polymers have attracted great attention in the application as photovoltaic donor materials in polymer solar cells(PSCs).Broad absorption,lower-energy bandgap,higher hole mobility,relatively lower HOMO energy levels,and higher solubility are important for the conjugated polymer donor materials to achieve high photovoltaic ***-chain engineering plays a very important role in optimizing the physicochemical properties of the conjugated *** this article,we review recent progress on the side-chain engineering of conjugated polymer donor materials,including the optimization of flexible side-chains for balancing solubility and intermolecular packing(aggregation),electron-withdrawing substituents for lowering HOMO energy levels,and two-dimension(2D)-conjugated polymers with conjugated side-chains for broadening absorption and enhancing hole *** the molecular structural optimization by side-chain engineering,the2D-conjugated polymers based on benzodithiophene units demonstrated the best photovoltaic performance,with powerconversion efficiency higher than 9%.

关键词： polymer solar cells conjugated polymers side-chain engineering photovoltaic materials 2D-conjugated polymers

Backstepping Approach to the Adaptive Regulator Design for a One-Dimensional Wave Equation with General Input Harmonic Disturbance

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Journal of Systems Science & Complexity 2017年第2期30卷 253-279页

作者： guo Wei SHAO zhi-Chao Department of Applied Mathematics School of StatisticsUniversity of International Business and EconomicsBeijing 100029China

This paper considers the parameter estimation and stabilization of an unstable one-dimen- sional wave equation with matched general harmonic disturbance at the controlled end. The back- stepping method for infinite-dimensional system is adopted in the design of the adaptive regulator. It is shown that the resulting closed-loop system is asymptotically stable. Meanwhile, the estimated parameter is shown to be convergent to the unknown parameter as time unes tn ~n^nitv

关键词： Backstepping method distributed parameter system disturbance rejection stability.

Effect of Dy substitution on the microstructure and magnetic properties of nanograin Nd-Fe-B single-phase alloys

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 335-339页

作者： zhi-an Chen Ji Luo zhi-meng guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nanocrystalline single-phase alloys with the nominal compositions （at%） of Nd12.3-xDyxFe79.7Zr0.8Nb0.8Cu0.4B6.0 （x=0, 0.5, 1.5, and 2.5） were prepared by melt-spinning and subsequent annealing. X-ray diffraction analysis shows that the as-spun ribbons were mainly com- posed of the amorphous phase. A slight content of Dy stabilizes the amorphous phase during annealing treatment. The grain size becomes smaller and the coercivity of the annealed ribbon is gradually improved with the increase of Dy content. Excessive Dy is harmful to the remanence. It is found that no intergramtlar phase exists between the grains by high-resolution transmission electron microscopy, and the grain boundaries are crystallographically coherent in the optimally annealed sample. The optimum magnetic properties of remanence （Jr=1.09 T）, coercivity （Hei=1048 kA/m）, and maximum magnetic energy product （（BH）m=169.5 kJ/m3） are obtained from the x=0.5 ribbon in a post heat-treated state （700℃, 10 min）.

关键词： NdFeB magnets dysprosium nanocrystalline amorphous grain size magnetic properties

Coral-like cobalt selenide/carbon nanosheet arrays attached on carbon nanofibers for high-rate sodium-ion storage

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Rare Metals 2023年第3期42卷 916-928页

作者： Jin-zhi Hu Wen-Jie Liu Ji-Hua Zheng guo-Chun Li Yong-feng Bu fen Qiao Jia-Biao Lian Yan Zhao Institute for Energy Research School of Energy and Power EngineeringJiangsu UniversityZhenjiang 212013China College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China

Cobalt selenide(CoSe_(2))has become a promising anode material for sodium-ion batteries(SIBs)due to its stable chemical properties,environmental friendliness,and high theoretical ***,the undesirable rate capacity and cycle stability of the anode materials largely limit its applications for SIBs due to the relatively low electronic conductivity and huge volume change during the Na+insertion/*** this study,electrostatic spinning combined with a wet chemical method is employed to synthesize coral-like composite material(CNF@c-CoSe_(2)/C),which is composed of CoSe_(2)/carbon nanosheet arrays(CoSe_(2)/C)and carbon nanofibers(CNFs).CoSe_(2)/C nanoflakes derived from metal-organic frameworks(MOFs)with high surface area and the porous structure can inhibit the pulverization and amorphization of CoSe_(2) during charge and discharge processes,thus significantly keeping the stability of the *** can limit the overgrowth of nanosheets and serve as a conductive *** to two-dimensional CoSe_(2)/C nanoflakes and pure CoSe_(2) nanoparticles,the composite can expose more active sites and effectively accelerate the diffusion of Na+,which displays enhanced rate capability(266.5 mAh·g^(-1) at 5.0 A·g^(-1))and cycling stability(268.3 mAh·g^(-1) after 100 cycles at 1.0 A·g^(-1)).Moreover,the rational preparation strategy for metal selenide-based heterostructure material presents a new way for high-performance SIB s.

关键词： Carbon nanofiber(CNF) Cobalt selenide(CoSe_(2)) Electrostatic spinning Sodium-ion storage

PI3K expression and PIK3CA mutations are related to colorectal cancer metastases

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World Journal of Gastroenterology 2012年第28期18卷 3745-3751页

作者： Yu-fen Zhu Bao-Hua Yu Da-Li Li Hong-Lin Ke Xian-zhi guo Xiu-Ying Xiao Department of Oncology Shanghai Xuhui District Center HospitalShanghai 200031 China Department of Pathology Fudan University Shanghai Cancer Center Shanghai 200032 China

AIM: To assess the significance of phosphatidylinositol 3-kinase (PI3K) in colorectal cancer (CRC) and toxicity of LY294002 in CRC cells with different metastatic abilities. METHODS: Sixty formalin-fixed and paraffin-embedded CRC tumor specimens were investigated. Adjacent normal colonic mucosa specimens from 10 of these cases were selected as controls. PI3K protein was detected by immunohistochemistry and PIK3CA mutations were investigated by gene sequencing analysis. A flowcytometry-based apoptosis detection kit was used to determine PI3K inhibitor-induced apoptosis in CRC cell lines SW480 and SW620. Expression of phosphorylated protein kinase B in CRC cell lines was detected by Western blotting. RESULTS: There was a significant difference in the proportion of primary lesions (30%, 18/60) vs metastatic lesions (46.7%, 28/60) that were positive for PI3K (P A resulting in E545A, and C.3140A>G resulting in H1047R; two novel missense mutations C.1624G>A and C.3079G>A; and three synonymous mutations (C.1641G>A, C.1581C>T and C.3027T>A). Exposure of SW480 cells to PI3K inhibitor for 48 h resulted in a significant increase of apoptotic cells in a dose-dependent manner [3.2% apoptotic cells in 0 μmol/L, 4.3% in 5 μmol/L, 6.3% in 10 μmol/L (P < 0.05), and 6.7% in 20 μmol/L (P < 0.05)]. Moreover, PI3K inhibitor induced a similar significant increase of apoptotic cells in the SW620 cell line for 48 h [3.3% apoptotic cells in 0 μmol/L, 13.3% in 5 μmol/L (P < 0.01), 19.2% in 10 μmol/L (P < 0.01), and 21.3% in 20 μmol/L (P < 0.01)]. CONCLUSION: High PI3K expression is associated with CRC metastasis. PI3K inhibitor induced apoptosis in CRC cells and displayed strong cytotoxicity for highly metastatic cells. PI3K inhibition may be an effective treatment for CRC.

关键词： Colorectal cancer PI3K PIK3CA Metastasis

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： Xihang Chen zhifeng Chen Menghua Li Weiwei guo Shuolong Yuan Liangwei Xu Chang Lin Xi Shi Wei Chen Shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine

MoS2 synaptic transistor with one-step manufacture

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Science China(Information Sciences) 2025年第1期68卷 357-365页

作者： Yihao guo Yang WANG Wenjie DENG Yi WU Jingtao LI Kexin LI Yuehui ZHAO Songlin YU Xiaoting WANG Yongzhe ZHANG Hui YAN Key Laboratory of Optoelectronics Technology of Education Ministry of China Faculty of Information TechnologyBeijing University of Technology Key Laboratory of Advanced Functional Materials Ministry of Education Faculty of Materials and ManufacturingBeijing University of Technology The 11th Research Institute of Electronics Technology Group Corporation

The synaptic transistor,which is a neuromorphic device with brain-like functions,has garnered significant attention due to characteristics such as low energy consumption,high integration,multiple functions,and high computational ***,the current synaptic transistor possesses a complicated structure and involves complex manufacturing steps,which is not conducive to low-cost,large-scale bionic ***,we introduce a simple MoS2synaptic transistor exhibiting robust synaptic *** transistor utilizes magnetron sputtering manufacture to combine the process of device metal electrode deposition and the introduction of defect states,which helps streamline the manufacturing process into a single *** long-term potentiation and long-term depression in photoelectric coordination are initially ***,biological functions,such as double pulse facilitation and the transformation behavior of short-term memory to long-term memory,are thoroughly evaluated,along with learning-forgetting-relearning ***,the device exhibits robust synaptic plasticity until incident light angles down to 30° to imitate the multi-to-one axon-cellular ***,a classical simulation of Pavlov's dog conditioned reflex is demonstrated along with the multiview extraction *** experimental results demonstrate a promising synaptic transistor with a simple structure,manufacturing technique,and excellent *** further indicates the potential for large-scale integration of bionic neuromorphic systems.

关键词： process optimization artificial synaptic device one-stepmanufacture synaptic plasticity bionic simulation

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