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Theoretical Investigation on Interaction between Guanine and Luteolin

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Chinese Journal of Chemical Physics 2013年第5期26卷 533-540,I0003页

作者： Lai-cai Li Kun-kun Bai Wan-fei Cai departement of Chemistry and Material Science Sichuan Normal University Chengdu 610066 China

The interacting patterns of the luteolin and guanine have been investigated by using the density functional theory B3LYP method with 6-31＋G＊ basis set. Eighteen stable structures for the luteolin-guanine complexes have been found respectively. The results indicate that the complexes are mainly stabilized by the hydrogen bonding interactions. Meanwhile, both the number and strength of hydrogen bond play important roles in determining the stability of the complexes which can form two or more hydrogen bonds. Theories of atoms in molecules and natural bond orbital have also been utilized to investigate the hydrogen bonds involved in all the systems. The interaction energies of all the complexes which were corrected by basis set superposition error are 6.04-56.94 kJ/mol. The calculation results indicate that there are strong hydrogen bonding interactions in the luteolin-guanine complexes. We compared the interaction between luteolin and four bases of DNA, and found luteolin-thymine was the strongest and luteolin-adenine was the weakest. The interaction between luteolin and DNA bases are all stronger than luteolin-water.

关键词： density functional theory Luteolin Guanine Hydrogen bond Atoms inmolecules Natural bond orbital

Substrate Temperature-dependent Physical Properties of Thermally Evaporated Sn4Sb6S13 Thin Films

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 79-88页

作者： A. Harizi M. Ben Rabeh M. Kanzari Laboratoire de Photovoltaique et Materiaux Semiconducteurs departement genie industriel ENIT-Universite Tunis E1 Manar BP 37 Le belvedere 1002 Tunis Tunisie Institut Preparatoire aux Etudes d'Ingenieurs de Tunis Universite de Tunisie Montfleury Tunisia

In this work, the homogenous thin films of sulfosalt Sn4Sb6S13 were successfully synthesized by the thermal evaporation technique onto coming 7059 glass substrates heated at various temperatures in the range of 30--200 ℃. The surface morphology and structural characteristics of Sn4Sb6S13 films were analyzed by atomic force microscopy, X-ray diffraction, and energy-dispersive X-ray, respectively. The X-ray diffraction analysis revealed that Sn4Sb6S13 thin films crystallized in monoclinic structure according to a preferential direction （6 11）. An improvement in the structural properties by increasing the substrate temperature was observed. The values of some important parameters such as absorption coefficient （x）, band gap （Eg）, refractive index （n）, extinction coefficient （k）, and dielectric constant （Eg） of thin film were determined. The absorption coefficient was larger than 105 cm-l in the visible range. The electron transition of Sn4Sb6S13 films was direct allowed with the values that decreased （2-1.69 eV） by increasing substrate temperature from 30 to 200 ℃,The dispersion data obeyed the single oscillator relation of the Wemple-DiDomenico model and Cauchy model. The electrical free carrier susceptibility and the carrier concentration of the effective mass ratio were estimated according to the model of Spitzer and Fan.

关键词： Thin film Thermal evaporation technique X-ray diffraction Optical parameters

Reflected solutions of backward stochastic differential equations driven by G-Brownian motion

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Science China Mathematics 2018年第1期61卷 1-26页

作者： Hanwu Li Shige Peng Abdoulaye Soumana Hima School of Mathematics Shandong University Jinan 250100 China Zhongtai Institute of Finance Shangdong University Jinan 250100 China Institut de Recherche Mathdmatiques de Rennes Universitd de Rennes 1 Rennes Cedex 35042 France departement de Mathdmatiques Universite de Maradi Maradi BP 465 Niger

In this paper, we study the reflected solutions of one-dimensional backward stochastic differential equations driven by G-Brownian motion. The reflection keeps the solution above a given stochastic process. In order to derive the uniqueness of reflected G-BSdes, we apply a "martingale condition" instead of the Skorohod condition. Similar to the classical case, we prove the existence by approximation via penalization. We then give some applications including a generalized Feynman-Kac formula of an obstacle problem for fully nonlinear partial differential equation and option pricing of American types under volatility uncertainty.

关键词： G-expectation reflected backward stochastic differential equations obstacle problems for fully nonlinear Pdes

Central role of altered phosphodiesterase 2-dependent signaling in the pathophysiology of cognition-based brain disorders

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Neural Regeneration Research 2025年第8期20卷 2302-2303页

作者： Asma Boulksibat Alessandra Tempio Barbara Bardoni Institut de Pharmacologie Moléculaire et Cellulaire CNRS UMR7275Inserm U1323ValbonneFrance

The second messengers 3',5'-cyclic adenosine monophosphate(cAMP)and 3',5'-cyclic guanosine monophosphate(cGMP)modulate molecular pathways that are involved in a large variety of cellular *** the brain,these processes include neurogenesis,neuronal differentiation,activation and function of microglia,and synaptic plasticity,finally resulting in memory formation.

关键词： formation processes finally

Lattice Boltzmann Modeling of Miscible Multicomponent Gas Mixtures in the Rarefied Regime

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Communications in Computational Physics 2022年第9期32卷 1179-1216页

作者： Michel Ho Sami Ammar Sebastien Leclaire Marcelo Reggio Jean-Yves Trepanier departement of Mechanical Engineering Polytechnique Montreal2500 Chemin de PolytechniqueMontreal H3T 1J4Canada

An extension to rarefied flow regimes of the lattice Boltzmann methodbased model for miscible mixtures developed by Vienne et al.(Physical Review E 100.2(2019):023309)is *** model is applied to study the gas phase separation phenomenon in mixture flows that traditional macroscopic approaches fail to *** extension includes a wall function approach with an empirical coefficient to define an effectivemean free path in solid geometries,which locally defines the kinematic viscosity and binary diffusion *** algorithm is also modified by a local multi-relaxation time collision operator and slip boundary conditions at solid *** mixture flow simulations are conducted through a 2D plane microchannel within the slip and early transition flow *** a miscible gaseous phase,the mixture loses its homogeneity and independent velocity profiles for each component are observed in the rarefied regime and captured with the current *** addition,the gas separation phenomenon increases with the rarefaction rate and the molecular mass *** individual treatment of the species within mixture flows in the developed lattice Boltzmann model helps understanding the increasing independent behavior of the individual specieswithin themixture as the regime becomesmore rarefied.

关键词： Lattice Boltzmann gaseous mixtures rarefied regimes

The V(z) Inversion Technique for Evaluation of an Adhesively Bonded Structure

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Chinese Physics Letters 2015年第12期32卷 78-82页

作者：刘婧徐卫疆胡文祥 OURAK Mohame'd DUBOIS Andre Institut d'Electronique de Microelectronique et de Nanotechnologie UMR CNRS 8520 Departement DOAE Universite de Valenciennes Valenciennes 59313 France Institute of Acoustics Tongji University Shanghai 200092 Laboratoire d'Automatique de Mdcanique et d'Informatique Industrielles et Humaines UMR CNRS 8201 Universite de Valenciennes Valenciennes 59313 France

Based on the fact that the evolution trace in incident angle and frequency of the resonance zeros of the reflec- tion coemcient function for a water charged layered medium is equivalent to its guided wave mode dispersion, the interracial adhesion of a three-layer aluminum-adhesive aluminum bonding structure is characterized nonde- structively by determining the interface shear stiffness kt associated with the interracial strength. The resonance reflection function is obtained experimentally by the V （z） inversion technique using an ultrasonic focused trans- ducer of wide-band and large angular aperture （up to ±45°）. The dispersion curves are numerically calculated, adjusting the parameter kt so that the difference between the dispersion curves and the angular-frequency tracing of the reflection zeros is minimum. The parameter kt at an interface of weakly adhered aluminum epoxy-resin is estimated to be 1014 N/m3.

关键词： The V

Advanced gastric cancer:Current treatment landscape and future perspectives

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World Journal of Gastroenterology 2016年第8期22卷 2403-2414页

作者： Antonia Digklia Anna Dorothea Wagner departement d’Oncologie Centre Hospitalier Universitaire Vaudois

Gastric cancer currently ranks fourth in cancer-related mortality worldwide. In the western world, it is most often diagnosed at an advanced stage, after becoming metastatic at distant sites. Patients with advanced disease(locally advanced or metastatic) have a somber prognosis, with a median overall survival of 10-12 mo, and palliative chemotherapy is the mainstay of treatment. In recent years, novel approaches using inhibition of human epidermal growth factor receptor 2(HER2) have demonstrated significant improvements in progression-free and overall survival, compared with chemotherapy alone, in first-line treatment of patients with overexpression of HER2. In addition, both second-line chemotherapy and treatment with the vascular endothelial growth factor receptor-inhibitor ramucirumab demonstrated significant benefits in terms of overall survival, compared with best supportive care, in randomized studies. Moreover, ramucirumab in combination with chemotherapy demonstrated further significant benefits in terms of progression-free and overall survival, compared with chemotherapy alone, in second-line treatment for patients with metastatic gastric cancer. A recently published molecular classification of gastric cancer is expected to improve patient stratification and selection for clinical trials and provide a roadmap for future drug development. Nevertheless, despite these developments the prognosis of patients with advanced gastric cancer remains poor. In this review we discuss current standards of care and outline major topics of drug development in gastric cancer.

关键词： Gastric cancer Phase III Clinical trials Chemotherapy Targeted therapy Perspectives

Postsynthetic functionalization of covalent organic frameworks

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National Science Review 2020年第1期7卷 170-190页

作者： Yusran Yusran Xinyu Guan Hui Li Qianrong Fang Shilun Qiu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Departement of Chemistry Jilin University

Covalent organic frameworks(COFs) have been at the forefront of porous-material research in recent years. With predictable structural compositions and controllable functionalities, the structures and properties of COFs could be controlled to achieve targeted materials. On the other hand, the predesigned structure of COFs allows fruitful postsynthetic modifications to introduce new properties and functions. In this review, the postsynthetic functionalizations of COFs are discussed and their impacts towards structural qualities and performances are comparatively elaborated on. The functionalization involves the formation of specific interactions(covalent or coordination/ionic bonds) and chemical reactions(oxidation/reduction reaction) with pendant groups, skeleton and reactive linkages of COFs. The chemical stability and performance of COFs including catalytic activity, storage, sorption and opto-electronic properties might be enhanced by specific postsynthetic functionalization. The generality of these strategies in terms of chemical reactions and the range of suitable COFs places them as a pivotal role for the development of COF-based smart materials.

关键词： covalent organic frameworks crystalline materials porous materials postsynthetic functionalization

Nonstandard finite-difference schemes for the two-level Bloch model

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第4期9卷 186-208页

作者： Marc E.Songolo Brigitte Bidegaray-Fesquet departement de Mathematiques et Informatique Universit´e de Lubumbashi 1825 Lubumbashi Republique Democratique du Congo Univ.Grenoble Alpes Grenoble INP LJK38000 GrenobleFrance

In this paper, we present splitting schemes for the two-level Bloch model. After proposing two ways to split the Bloch equation, we show that it is possible in each case togenerate exact numerical solutions of the obtained sub-equations. These exact solutionsinvolve matrix exponentials which can be expensive to compute. Here, for 2×2 matriceswe develop equivalent formulations which reduce the computational cost. These splittingschemes are nonstandard ones and conserve all the physical properties (Hermicity, positiveness and trace) of Bloch equations. In addition, they are explicit, making effectivetheir implementation when coupled with the Maxwell’s equations.

关键词： Bloch equation exponential of a matrix exact finite-difference schemes nonstandard finite-difference schemes splitting method.