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Properties on Solutions of Some q-Difference Equations

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1877-1886页

作者： Bao Qin chen Zong Xuan chen sheng LI School of Mathematical Sciences South China Normal University Guangzhou 510631 P. R. China

We consider the properties on solutions of some q-difference equations of the form ∑ n j=0 aj（z）f（qj z）=an＋1（z）, where a0（z）,..., an＋1（z） are meromorphic functions, a0（z）an（z） ≠ 0 and q ∈ C such that 0 〈｜q｜ ≤ 1. We give estimates on the upper bound for the length of the gap in the power series of entire solutions of （＊） when the coefficients a0（z）,..., an＋1（z） are polynomials and 0 〈｜q｜〈 1. For some special cases, we give estimates of growth of f（z）. And we also show that the case 0 〈｜q｜〈 1 is different from the case ｜q｜=1.

关键词： q-difference equation entire coefficient Fabry gap growth

Multi-period integrated natural gas and electric power system probabilistic optimal power flow incorporating power-to-gas units

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Journal of Modern Power Systems and Clean Energy 2017年第3期5卷 412-423页

作者： Guoqiang SUN Shuang chen Zhinong WEI sheng chen College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China

The increasing adoption of gas-fired power plants directly strengthens the coupling between electric power and natural gas systems. Current industrial practice in optimal power flow for electric power systems has not taken the security constraints of gas systems into consideration, resulting in an overly-optimistic solution. Meanwhile, the operation of electric power and natural gas systems is coupled over multiple periods because of the ramp rate limits of power generators and the slow dynamical characteristics of gas systems. Based on these motivations, we propose a multi-period integrated natural gas and electric power system probabilistic optimal power flow(M-GEPOPF) model, which includes dynamic gas flow models. To address the uncertainties originating from wind power and load forecasting, a probabilistic optimal power flow(POPF) calculation based on a three-point estimate method(3 PEM) is adopted. Moreover, power-togas(Pt G) units are employed to avoid wind power curtailment and enable flexible bi-directional energy flows between the coupled energy systems. An integrated IEEE RTS 24-bus electric power system and the Belgian 20-node natural gas system are employed as a test case to verify the applicability of the proposed M-GEPOPF model, and to demonstrate the potential economic benefits of Pt G units.

关键词： Natural gas and electric power system Network interdependency Optimal power flow Uncertainty Power-to-gas unit

Short-range clutter suppression method combining oblique projection and interpolation in airborne CFA radar

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Journal of Systems Engineering and Electronics 2021年第1期32卷 92-102页

作者： HU Yili ZHAO Yongbo PANG Xiaojiao chen sheng National Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China

The airborne conformal array(CFA)radar's clutter ridges are range-modulated,which result in a bias in the estimation of the clutter covariance matrix(CCM)of the cell under test(CUT),further,reducing the clutter suppression performance of the airborne CFA *** clutter ridges can be effectively compensated by the space-time separation interpolation(STSINT)method,which costs less computation than the space-time interpolation(STINT)method,but the performance of interpolation algorithms is seriously affected by the short-range clutter,especially near the platform *** distributions of CFA are free,which yields serious impact that range spaces of steering vector matrices are non-orthogonal complement and even no longer ***,a new method is proposed that the shortrange clutter is pre-processed by oblique projection with the intersected range spaces(OPIRS),and then clutter data after being pre-processed are compensated to the desired range bin through the STSINT *** OPIRS also has good compatibility and can be used in combination with many existing *** the same time,oblique projectors of OPIRS can be obtained in advance,so the proposed method has almost the same computational load as the traditional compensation *** addition,the proposed method can perform well when the channel error *** simulation results verify the effectiveness of the proposed method.

关键词： airborne conformal arrays(CFA)radar oblique projection intersected range space short-range clutter suppression

Mechanically strong,flexible,and multi-responsive phase change films with a nacre-mimetic structure for wearable thermal management

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Journal of Energy Chemistry 2022年第12期75卷 229-239,I0006页

作者： Jiankang Zhang Jiahui Mu sheng chen Feng Xu Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing 100083China

Phase change materials(PCMs)are a highly promising candidate for thermal energy storage owing to their large latent heat and chemical ***,their intrinsic brittle induces poor flexibility and low mechanical strength,which limits them use for wearable thermal ***,the electrical insulation and weak solar absorption make them lack multi-responsive ***,we report a facile strategy to synthesize mechanically strong and flexible multi-responsive phase change films by stirring an aqueous dispersion of cellulose nanofibrils(CNFs),MXene(Ti_(2)C_(3))nanosheets,and polyethylene glycol(PEG),followed by air-drying self-assembly and coating with hydrophobic *** hydrogen bonds and nacre-mimetic synergistic toughening networks formed by ternary CNFs,Ti_(2)C_(3)nanosheets,and PEG endow films with high mechanical strength(16.7 MPa)and strain(10.4%),which are 18.6 and 8.7 times higher than those of pure PEG film,*** films exhibit outstanding flexibility and do not crack or fracture even when bent,twisted,and folded into a complex small ***,the laminar structure formed by the self-assembly Ti_(3)C_(2)nanosheets enhances electrical conductivity(3.95 S/m)and solar absorption,affording excellent electro-thermal(68.3%–81.0%)and solarthermal(85.6%–90.6%)conversion efficiency,thus achieving multi-response to external stimuli(electron/solar radiation).In addition,the as-prepared films also deliver large latent heat(136.1 J/g),outstanding cyclic and shape stability,leak-free encapsulation even under compressed at above 5000 times its weight,excellent hydrophobicity(131.4°),and self-cleaning *** work paves the way for developing flexible,mechanically strong,and self-cleaning phase change film with multi-responsive function for wearable thermal management devices under high humidity condition.

关键词： Phase change materials Flexible Mechanically strong Multi-responsive Wearable thermal management

Semi-Simple Algebras and Normality of Closed Subsets in Standard Table Algebras

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Wuhan University Journal of Natural Sciences 2017年第5期22卷 369-372页

作者： chen sheng'an School of Mathematics and Statistics Hubei University ofScience and TechnologyXianning 437100HubeiChina

By using Artin-Wedderburn Theorem and the decomp- osition of central edepotent, several results about normality on closed subsets in standard table algebras are generalized to complex semi-simple algebras and the proo... 详细信息

关键词： semi-simple algebra standard table algebra normal closed subset central idempotent

Redox signaling-governed drug-tolerant persister cancer cell:a key spark of treatment failure

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Signal Transduction and Targeted Therapy 2022年第4期7卷 955-957页

作者： Liwu Fu Zhe-sheng chen State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineGuangdong Esophageal Cancer InstituteCancer CenterSun Yat-Sen UniversityGuangzhou 510060China Department of Pharmaceutical Sciences College of Pharmacy and Health SciencesSt.John’s UniversityQueensNY 11439USA Institute for Biotechnology St.John’s UniversityQueensNY 11439USA

In a recent study published in EMBO Molecular medicine,Zhang et *** a novel insight regarding better knowledge of the drug resistant contribution of drug-tolerant persister(DTP)state in tumor evolution,especially in terms of mechanistic insights into redox regulation involved,unambiguously establishing a novel therapeutic strategy of treating multi-drug-resistant(MDR)cancer cells and preventing tumor recurrence by disequilibrating Niemann–Pick C1-like 1(NPC1L1)-mediated redox homeostasis.

关键词： cancer homeostasis insight

Progress in the studies on the molecular mechanisms associated with multidrug resistance in cancers

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Acta Pharmaceutica Sinica B 2023年第3期13卷 982-997页

作者： Lei Zhang Biwei Ye Zhuo chen Zhe-sheng chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Agriculture and Forestry University Fuzhou 350002China Department of Pharmaceutical Sciences College of Pharmacy and Health SciencesSt.John's UniversityNew YorkNY 11439USA

Chemotherapy is one of the important methods to treat cancer,and the emergence of multidrug resistance(MDR)is one major cause for the failure of cancer *** all anti-tumor drugs develop drug resistance over a period of time of application in cancer patients,reducing their effects on killing cancer *** can lead to a rapid recurrence of cancers and ultimately patient *** may be induced by multiple mechanisms,which are associated with a complex process of multiple genes,factors,pathways,and multiple steps,and today the MDR-associated mechanisms are largely *** this paper,from the aspects of protein–protein interactions,alternative splicing(AS)in pre-mRNA,non-coding RNA(ncRNA)mediation,genome mutations,variance in cell functions,and influence from the tumor microenvironment,we summarize the molecular mechanisms associated with MDR in *** the end,prospects for the exploration of antitumor drugs that can reverse MDR are briefly discussed from the angle of drug systems with improved targeting properties,biocompatibility,availability,and other advantages.

关键词： Multidrug resistance(MDR) ABC transporter family Signaling pathway Alternative splicing(AS) Gene mutation None-coding RNA(ncRNA) Tumor microenvironment

Hyposmia: a possible biomarker of Parkinson's disease

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Neuroscience Bulletin 2014年第1期30卷 134-140页

作者： Qian Xiao sheng chen Weidong Le Institute of Neurology Ruijin Hospital Shanghai Jiao Tong University School of Medicine Institutes of Translational Medicine 1st Affiliated Hospital of Dalian Medical Universtiy

Hyposmia, identified as reduced sensitivity to odor, is a common non-motor symptom of Parkinson＇s disease （PD） that antedates the typical motor symptoms by several years. It occurs in -90% of early-stage cases of PD. In addition to the high prevalence, the occurrence of hyposmia may also predict a higher risk of PD. Investigations into hyposmia and its relationship with PD may help elucidate the underlying pathogenic mechanisms. This review provides an update of olfactory dysfunction in PD and its potential as a biomarker for this devastating disease.

关键词： hyposmia Parkinson's disease olfaction biomarker

FOURTH ORDER EVOLUTION EQUATIONS WITH SLOWLY VARYING DEPTH AND CURRENT AND STABILITY OF STOKES WAVES

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Journal of Hydrodynamics 1991年第4期3卷 21-42页

作者： Chin-pu, Zhou Yan-sheng, chen Zhongshan Univ Guangzhou China

Fourth order evolution equations with slowly varying depth and current have been derived for two-dimensional modulation Stokes waves in arbitrary water depth. In the absence of current and variation of topography the equations reduce to those of Brinch-Nielsen & Jonsson, and the third order terms agree with those of Turpin & Benmoussa & Mei. Stokes wave in the slowly varying depth and current is specified, and its instability to small sidebands is studied in detail. A general criterion of instability with growth rate 0(Ε2) is given, and the maximum growth rate has also been obtained. An interesting result is that in the fourth-order theory the existence of current and varying depth leads the Stokes wave to be always unstable to small sidebands disturbance.

关键词： Mathematical Techniques Applications Mathematical Techniques Perturbation Techniques Water Waves Mathematical Models