Design for Interactions

In the chemical field, if the factors are reactants, the effect of each reactant alone is zero; only two- or three factor combinations produce results. Given many possible causes of an observed reaction, the design described here facilities the identification of the contributing factors.     

Mode Interactions With Symmetry

We prove several results concerning problems invariant under the action of an arbitrary compact Lie group Γ. These include the existence of mixed-mode solutions and secondary Hopf bifurcations. We provide a definition of mode interaction which applies to a wide selection of problems and consider the unfolding of the equations characterizing such problems. Where appropriate, we distinguish the case when I acts trivially on one of the modes     

Interactions of interfacial arc cracks

The interaction of two interfacial arc cracks around a circular elastic inclusion embedded in an elastic matrix is examined. New results for stress intensity factors for a pair of interacting cracks are derived for a concentrated force acting in the matrix. For verifying the point load solutions, stress intensity factors under uniform loading are obtained by superposing point force results. For achieving this objective, a general method for generating desired stress fields inside a test region using point loads is described. The energetics of two interacting interfacial arc cracks is discussed in order to shed more light on the debonding of hard or soft inclusions from the matrix. The analysis based on complex variables is developed in a general way to handle the interactions of multiple interfacial arc cracks/straight cracks.     

Interactions between Adsorbed Gelatin Layers

Abstract

The interaction energies between gelatin coated surfaces at various electrolyte and pH conditions have been determined and are reported. These experiments were performed by attaching a small glass sphere to an AFM tip, allowing the gelatin to adsorb, and then moving the AFM tip toward an optically flat surface. The importance of adsorption conditions as well as the current conditions are discussed. A number of general trends have been observed. The layer was seen to expand with increasing pH. At low pH the surfaces are negative and the gelatin positive and thus the polyampholyte tends to lay relatively flat. As the pH is increased the strong interaction between the surface and polyampholyte decreases and so the gelatin extends away from the surface. On changing electrolyte concentration, no effect was seen at the isoelectric point, however, the layer was observed to swell at more alkaline pHs.

By oscillating the AFM tip as the surfaces are moved together and determining the response of the tip to the oscillation, some mechanical properties of the gelatin may be obtained. In particular, the viscoelastic properties may be determined from the amplitude of oscillation and the phase lag of the response. The results show that when the adsorbed gelatin layers interact, the response changes from being primarily viscous to primarily elastic in nature and as the adsorbed layers are compressed further an almost entirely elastic response is noted.     

Interactions between Ti and alumina-based ceramics

Reactive metal coatings have been frequently used on ceramic materials for various purposes. However, little work was done in the past to understand the interactions between coating and ceramic substrates and their effects on the mechanical properties of the ceramics. In this study, titanium coatings were applied to single-crystal (sapphire) and polycrystalline alumina to study the interface reactions. Also, the effect of the coating on the mechanical properties of the substrates was quantified in terms of modulus of rupture (MOR) in four-point bending strength. Reactions between the coating and the Al₂O₃-based substrates at 980°C caused the formation of a new phase, Ti₃Al[O], and a significant decrease (15%–65%) in the MOR strength of the ceramic materials. This study showed that in polycrystalline alumina, interactions between titanium and the glassy grain-boundary phase in the ceramic materials were responsible for reduction in the MOR strength, while the effect of thermal expansion mismatch between titanium and the ceramic substrate appeared to be dominant for singlecrystal alumina.     

Interactions of chondrocytes with methacrylate copolymers

Copolymers of poly(ethylmethacrylate) (PEMA) and tetrahydrofurfurylmethacrylate (THFMA) have been shown to exhibit potential as a biomaterial for use in cartilage repair. However, the interactions of chondrocytes with the polymer surface is not well understood. A series of novel methacrylate copolymers containing PEMA, THFMA and hydroxyethylmethacrylate (HEMA) were prepared and the ability of these various copolymers to support chondrocytes attachment in vitro has been assessed by the Alamar blue assay for cell number and environmental scanning electron microscopy (ESEM). As the mole fraction of HEMA in PEMA/THFMA/HEMA copolymers increased, chondrocyte attachment to the polymer surface in 24 h decreased. Chondrocytes maintained a rounded morphology and were strongly attached on the THFMA/PEMA polymer surface, but as the mole fraction of HEMA increased the cells present became much smaller with fewer cell to cell interactions. The effect of pre-adsorbing fibronectin on to the polymer surface on cell attachment was assessed both in the presence and absence of serum. Chondrocyte attachment was significantly reduced in serum-free medium. Pre-adsorption of fibronectin on to the copolymer surface substantially increased cell attachment in all cases. In conclusion, chondrocyte attachment and proliferation on these copolymers may be controlled by changes in the polymer surface chemistry and is highly sensitive to the presence of proteins either in the culture media or pre-adsorbed on to the copolymer surface. © 1998 Kluwer Academic Publishers     

Some Interactions Between Gelatin and Surfactants

Abstract

The interactions between gelatin and sodium dodecyl sulphate (SDS) were studied with respect to the viscosity increase. Beside the temperature, pHand SDS concentration, we learned that the starting viscosity is of importance. Obviously, the high molecular parts have a major influence. These interactions can be suppressed by a suitable modification.     

基于相互影响的R＆D项目组合选择

结合企业对于资源投入以及收益的阶段性要求，改进了相互独立的R＆D项目组合选择摹本模型，以此为基础先后建立了基于多个项目间收益相互影响、技术相互影响以及资源相互影响同时发生的一般模型。结合具体的计算实例，验证了一般模型的有效性并分析了考虑项目间相互影响与否而产生的R＆D项目组合选择差异。     

磁性材料中的晶粒相互作用

磁性材料中的晶粒相互作用对材料的宏观磁性有决定性影响。相互作用可分为晶粒之间的长程静磁相互作用和近邻晶粒之间的交耦合相互作用。     

Interactions of Human Insulin with Deae-Dextran

In order to develope an oral drug delivery system for human Insulin, interactions of human insulin with DEAE-dextran was studied under different conditions. Effects of various inoic strenghts (0.02 M, 0.067 M, 0.01 M and 0.20 M), different temperatures (25C, 37C and 45C) and pH's (6.9, 7.4 and 8) as well as lyophilization and the addtion of urea on the interaction were perfromed. Bound human insulin was separated from the unbound insulin by gel chromatogrphy. Insulin concentratin was determined spectrophotometrically at 276 nm. The amout of fraction bound was calculated form area under the curve of the chromatographic peaks. The experiments showed that ionic strength had no effect on the binding capacity. However, fraction bound was increased with increased temprature. Under a pH range studies, maximum biniding was observed at pH 7.4. The presence of 0.042 M urea seems to increase the binding of insulin to have no effect on insulin intergrity.     

Interactions of Inert Confiners with Explosives

The deformation of an inert confiner by a steady detonation wave in an adjacent explosive is investigated for cases where the confiner is sufficiently strong (or the explosive sufficiently weak) such that the overall change in the sound speed of the inert is small. A coupling condition which relates the pressure to the deflection angle along the explosive-inert interface is determined. This includes its dependence on the thickness of the inert, for cases where the initial sound speed of the inert is less than or greater than the detonation speed in the explosive (supersonic and subsonic inert flows, respectively). The deformation of the inert is then solved by prescribing the pressure along the interface. In the supersonic case, the detonation drives a shock into the inert, subsequent to which the flow in the inert consists of alternating regions of compression and tension. In this case reverberations or ‘ringing’ occurs along both the deflected interface and outer edge of the inert. For the subsonic case, the flow in the interior of the inert is smooth and shockless. The detonation in the explosive initially deflects the smooth interface towards the explosive. For sufficiently thick inerts in such cases, it appears that the deflection of the confiner would either drive the detonation speed in the explosive up to the sound speed of the inert or drive a precursor wave ahead of the detonation in the explosive. Transonic cases, where the inert sound speed is close to the detonation speed, are also considered. It is shown that the confinement affect of the inert on the detonation is enhanced as sonic conditions are approached from either side.     

基于相互影响的R&D项目组合选择

结合企业对于资源投入以及收益的阶段性要求,改进了相互独立的R&D项目组合选择基本模型,以此为基础先后建立了基于多个项目间收益相互影响、技术相互影响以及资源相互影响同时发生的一般模型.结合具体的计算实例,验证了一般模型的有效性并分析了考虑项目间相互影响与否而产生的R&D项目组合选择差异.     

Optimized Coiled-Coil Interactions for Multiplexed Peptide-PAINT

Super-resolution microscopy has revolutionized how researchers characterize samples in the life sciences in the last decades. Amongst methods employing single-molecule localization microscopy, DNA points accumulation for imaging in nanoscale topography (DNA-PAINT) is a relatively easy-to-implement method that uses the programmable and repetitive binding of dye-labeled DNA imager strands to their respective docking strands. Recently developed Peptide-PAINT replaces the interaction of oligonucleotides by short coiled-coil peptide sequences leading to an improved labeling scheme by reducing linkage errors to target proteins. However, only one coiled-coil pair is currently available for Peptide-PAINT, preventing multiplexed imaging. In this study, the initial Peptide-PAINT E/K coil is improved by modifying its length for optimized binding kinetics leading to improved localization precisions. Additionally, an orthogonal P3/P4 coil pair is introduced, enabling 2-plex Peptide-PAINT imaging and benchmarking its performance and orthogonality using single-molecule and DNA origami assays. Finally, the P3/P4 peptide pair is used to image the human epidermal growth factor receptors 2 (ErbB2/Her2) in 2D and 3D at the single receptor level using genetically encoded peptide tags.