Two New Aristolochic Acid Analogues from the Roots of Aristolochia contorta with Significant Cytotoxic Activity

Twelve compounds, including two new aristolochic acid analogues with a formyloxy moiety (9–10) and 10 known aristolochic acid derivates (1–8 and 11–12), were obtained from the roots of Aristolochia contorta. Their structures were elucidated using extensive spectroscopic methods. Their cytotoxic activity in human proximal tubular cells HK-2 was evaluated by the MTT method, which has been widely used to assess cell viability. Among these molecules, compounds 3 and 9 were found to be more cytotoxic. Furthermore, molecular modeling was used to evaluate, for the first time, the interactions of compounds 3 and 9 with the target protein organic anionic transporter 1 (OAT1) that plays a key role in mediating aristolochic acid nephropathy. Structure–activity relationships are briefly discussed.     

Single-crystal structure of two-dimensional organic framework based on donor-acceptor interactions with charge-transfer effect

Two charge-transfer single crystals induced by donor-acceptor interactions were obtained. The presence of different solvent molecules led to 1D(linear) or 2D self-assembly modes. More interestingly, the 2 D organic framework, a layer-by-layer 2D organic framework single crystal, showed a stronger charge-transfer effect than the 1D cocrystal.     

Controlled synthesis of dendritic ruthenium nanostructures under microwave irradiation and their catalytic properties for p-chloronitrobenzene hydrogenation

Transition Metal Chemistry - In this study, the shape-controlled synthesis of ruthenium (Ru) nanostructures was examined using microwave irradiation. Dendritic Ru nanostructures, with an average...     

Characterization and properties of plywood bioadhesive derived from cottonseed protein and sawdust cellulose

Cellulose - The development of plant adhesive with good bonding strength, water resistance and thermal stability remains challenging to replace formaldehyde-based adhesive resins that usually...     

Study on Deformation of Polycrystalline Aluminum Alloy Using Moiré Interferometry

Polycrystalline aluminum alloy is manufactured by annealing, compared to the width of the specimen, the size of the grains can not be omitted, which makes the specimen anisotropic. Under uniaxial tension, the deformation field is inhomogeneous. In this study, moiré interferometry is successfully applied to measure the deformation of the polycrystalline specimen. The experimental results presented the stress versus strain responses of the marked grains in different orientations and different shapes. By using fringe centering method, the strain distributions under certain load in the centers and on the boundaries of the grains are analyzed.     

SMALE HORSESHOES AND CHAOS IN DISCRETIZED PERTURBED NLS SYSTEMS(Ⅱ)—SMALE HORSESHOES

2000MathematicsSubjectClassification:35Q Introduction ContinueRef.[1],inthispart,weapplythegeneralizedConley Moserconditions[2]toshowtheexistenceofSmalehorseshoesinbelowthediscreteNLSsystems(1).Considerthefollowingn particle(any2相似文献   

Progress in thermal-mechantical effects induced by laser

对激光辐照诱导的热与力学问题研究进展进行了综述,包括材料在高温、高升温速率下的本构关系,典型薄板和柱壳等结构在激光辐照下的热力破坏效应,多层材料体系的激光破坏行为等几个方面,并着重介绍了包含相变与烧蚀过程的激光破坏分析模型与机制研究,激光辐照效应的流-热-固耦合数值模拟方法,以及短脉冲激光引起的冲击与破坏机理等方面的研究新进展.     

Representation theorem for linear,isotropic tensor functions of a skew argument

The present paper offers two proofs of the representationtheorem for linear,isotropic tensor functions of a skew ar-gument.The first proof is new.The second one is basicallyalong the lines of reasoning exploited in[1].but more con-cise,and it corrects some errors committed in[1].     

Second order effects in an elastic half-space acted upon by a non-uniform normal load

A closed form solution to the second order elasticity problem, when an isotropic compressible elastic half-space undergoes a deformation owing to a non-uniformly distributed normal load, is presented. The method of integral transform is employed and the case when loading is distributed, in accordance with Hertz's law, is discussed. The limiting solution for incompressible isotropic elastic material is also derived. Numerical calculations for the second order elastic material for the displacement and the normal stress in thez-direction are carried out. It is found that, in comparision to the linear elastic case, the displacement increases and the normal stress decreases in the second order elastic material

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Sommario Si presenta una soluzione del secondo ordine in forma chiusa del problema di un semi-spazio elastico isotropo compressibile soggetto a un carico normale distribuito non uniformemente, ottenuta mediante il metodo delle trasformate integrali. Si discute il caso del carico distribuito secondo la legge di Hertz; si deriva anche la soluzione limite per materiale elastico isotropo incompressibile. Si ottengono numericamente alcuni risultati relativi a spostamenti e tensioni normali nella direzione z: si trova che, a paragone del caso elastico lineare, gli spostamenti aumentano e le tensioni diminuiscono nel materiale elastico del secondo ordine.

     

Fluorescein-bridged Perylene Bisimide Dimer for Use as Liquid Crystal: Studies on Mesomorphic and Fluorescence Properties

Journal of Fluorescence - A novel fluorescein-bridged perylene bisimide (PBI) dimer for liquid crystal (LC) with geometrically symmetric structure was developed. The mesomorphic results indicated...