Academic literature on the topic 'Inter-component adhesion'

The global behavior of composite materials is strongly influenced by the quality of adhesion between different components. A component can be single phase, like fibers or particles used as reinforcement in a homogenous matrix, or a multiphase material like a layer in long-fiber laminate. In the latter case the degradation of adhesion implies the separation of the layers, known as delamination. Among all different failure mechanisms, Delamination is considered to be the most prominent mode of failure in fiber-reinforced laminates as a result of their relatively weak inter-laminar strength. When laminated structures are subjected to static, dynamic or cyclic loadings, the inter-laminar adhesion strength between individual plies tends to deteriorate significantly and act as the origin of the final failure. Therefore, an efficient and reliable design tool capable of predicting delamination could improve the durability for composite laminates. There exist damage mechanics based formulations capable of simulating the delamination crack growth in carbon/glass fiber epoxy based composite laminates. The present study is focused on taking a step forward in this respect. At first, already existed local interface models effectiveness is tested and results are successfully compared with available experimental data for UD IMS/924 Carbon/fiber epoxy composite laminate. Next, a non-local integral-type regularization scheme is introduced to overcome the spurious localization problem associated to the existing local model. Basic concepts and mathematical modeling of Non-Local damage evolution law are comprehensively studied and presented in this study. Finite Element simulation results based on proposed model are discussed in detail and are compared with experimental results.

Long-Term Quality Control of the Cytokine & Growth Factors and Cell Adhesion Molecule Arrays at the Randox Evidence InvestigatorMulti component assays are a promising development in laboratory medicine. Reproducibility and standardization of the used technology is crucial for the quality of the results. In our laboratory several studies were carried out in a period of more than two years using the Randox Evidence Investigator. We applied the Cytokine & Growth Factors and Cell Adhesion Molecule Array from which reference values could be obtained. Cytokines are not useful in low grade inflammation or in normal persons as the levels are too low to detect. However growth factors and cell adhesion molecules could be determined in those studies. Outcomes with the arrays were compared with conventional assays such as ELISA. The correlations of IL-6 and IL-10 were very good and that of s-ICAM acceptable. Inter-assay coefficients of variation could be calculated by using the same control level material during those years. The system turned out to be easy to handle and very stable over a long period of time with CV's of about 8-12%. The results obtained are not dependent of the lot number of the arrays or apparatus as two different apparatus gave same outcomes.

The object of the study is the sealing elements of the packer. The fundamental principle of the cluster model is the assumption that the sum of the relative volume fractions of two structural elements of a natural nanocomposite (loosely packed matrix and nanoclusters) is equal to one –  This approach is incorrect because it is violated when the nanoclusters are immersed in a loosely packed matrix. In this regard, a new relationship is proposed that relates the relative volume fractions of the loosely packed matrix and the part of nanoclusters immersed in it –  Calculation formulas are obtained for the relative fractions of the loosely packed matrix and the interphase region. The paper shows that such an assumption is unfounded due to the indispensable immersion of clusters in a loosely packed matrix, and in this regard, a new relationship is proposed linking the relative volume fractions of the loosely packed matrix and the part of nanoclusters immersed in it. For a composite with a matrix, a mixture of synthetic butadiene nitrile and hydrogenated butadiene nitrile rubber and the addition of a copper nanoparticle, it is shown that in a natural nanocomposite, which is the polymer under study in an amorphous state, the time dependences of the relative volume fractions of the regions of inter-component adhesion and the loosely packed matrix coincide quite well with each other. The application of the above relationship between the volume fractions of a loosely packed matrix and nanoclusters allows to reformulate the known equations of parallel and sequential micromechanical models, as well as the Kerner equation for a more complex micromechanical model used to describe the effect of strengthening the elastic modulus of nanocomposites

Chemical treatment (hazardous waste) is the conversion of hazardous waste into non-toxic gases, to change or change the chemical characteristics of waste Treatment methods are used, for example in water By decreasing solubility. OracidityNeutralization or pH adjustment (neutralization or precipitation), oxidation and reduction, hydrolysis and Photosynthesis, chemical oxidation (ozonation, (electrolytic oxidation, hydrogen peroxide) and chemical removal (alkali metaldichlorine, alkali)chemical treatment processes Various (commonly used) including metallization/ soCommonly Activated Chemical Treatment Processes: Chemical Precipitation, neutralization absorption, disinfection (chlorine, ozone, UV light) and ion exchange. from plant kingdomCommon natural fibres obtained are Cotton, Flax, Jute, Bamboo, Sisal and Jute, Natural fibres. The main component Natural fibres. The main component Popular as angora and mohair We get fibres, plant fibres include seed hairs such as cotten; Flax andstem (or bast) fibres like jute, leaf fibres like sisal; and coconut-like husks fibres. Animal fibres also include secretions such as wool, hair, and silk. Research significance: In this paper, various chemical properties of in natural fibre-reinforced composites Use natural fibres Changes have been reviewed. Alkali, Silane, Acetylation, Benzoylation, Acrylation, malate coupling agents, isocyanates, Permanganate and other chemical treatments are discussed. to the fibre surface Chemical treatment of fibre between polymer matrixAimed at improving adhesion. Water absorption of composites decreases and their mechanical Properties are improved. Method: Fuzzy TOPSIS (Order by Similarities for Ideal Solution technique for prioritization) similar options. Further It also automates the process and selection Ambiguity, uncertainty in the process Can also be used to relieve Technology in general Used to solve decision problems. This is for all alternatives in the technique problem Based on inter-comparison. Alternative: Cotton, Jute, Flax, Hemp, Ramie and Sisal. Evaluation parameters: Density, Elongation, Tensile strength and Young’s modulus. Result: Chemical Treatments of Natural Fibre in Sisal is got the first rank whereas is the Hemp is having the Lowest rank.Conclusion: Chemical Treatments of Natural Fibre in Sisal is got the first rank whereas is the Hemp is having the Lowest rank.

The object of the study is the sealing elements of the packer. The fundamental principle of the cluster model is the assumption that the sum of the relative volume fractions of two structural elements of a natural nanocomposite (loosely packed matrix and nanoclusters) is equal to one – This approach is incorrect because it is violated when the nanoclusters are immersed in a loosely packed matrix. In this regard, a new relationship is proposed that relates the relative volume fractions of the loosely packed matrix and the part of nanoclusters immersed in it – Calculation formulas are obtained for the relative fractions of the loosely packed matrix and the interphase region. The paper shows that such an assumption is unfounded due to the indispensable immersion of clusters in a loosely packed matrix, and in this regard, a new relationship is proposed linking the relative volume fractions of the loosely packed matrix and the part of nanoclusters immersed in it. For a composite with a matrix, a mixture of synthetic butadiene nitrile and hydrogenated butadiene nitrile rubber and the addition of a copper nanoparticle, it is shown that in a natural nanocomposite, which is the polymer under study in an amorphous state, the time dependences of the relative volume fractions of the regions of inter-component adhesion and the loosely packed matrix coincide quite well with each other. The application of the above relationship between the volume fractions of a loosely packed matrix and nanoclusters allows to reformulate the known equations of parallel and sequential micromechanical models, as well as the Kerner equation for a more complex micromechanical model used to describe the effect of strengthening the elastic modulus of nanocomposites

Abstract Monoclonal antibodies (mAb) directed to a range of cell surface antigens on malignant lymphoid cells are increasingly a key component of the treatment of a whole range of haematological malignancies and remain the focus of intense ongoing clinical investigation. The anti-CD20 mAb rituximab has over the last decade substantially increased clinical responses leading to a marked improvement in outcome for many patients with B cell malignancies. The pursuit of mAb to improve on the efficacy of rituximab is currently undergoing intensive research, with several new candidate mAb now undergoing clinical evaluation. These newer generation anti-CD20 mAb have largely focused on improvements in increasing the affinity of the Fc-FcgR interactions and the recruitment of immune effector cells as these are thought to underlie much of the mAb therapeutic effect. However the immune effector functions of mAb does not explain why certain mAb specificities are more potent than others in inducing tumour cell death. Previously, we have demonstrated that Type II anti-CD20 mAb (Tositumomab) were able to evoke direct cell death via a non-apoptotic mode of death that appeared to be linked with the induction of homotypic adhesion. In this study we have considerably extended these observations using both in vitro cell lines and primary CLL cells. Using time-lapse microscopy and the FRAP technique, we revealed that de novo F-actin synthesis within cell contact area is critical for both homotypic adhesion and cell death induced by both Type II anti-CD20 mAb (Tositumomab) and HLA DR Class II mAb (L243). We have demonstrated that the mode of cell death engaged is rapid, non-apoptotic and non-autophagic as detected by inability to inhibit this form of cell death with pan-caspase inhibitor QVD, overexpressed Bcl2 as well as with siRNA against key autophagy regulators Beclin 1 and ATG-12. Scanning and transmission electon microscopy studies revealed the cytoplasmic nature of cell death involving lysosomes which swell and then disperse their contents into the cytoplasm. The increase in the lysosomal compartment followed by lysosome membrane permeabilisation and subsequent cell death has also been confirmed by flow cytometry and fluorescence microscopy, using lysosome specific probe lysotracker. Furthermore, this cell death has been shown to be dependent on active V-type ATPase but not on chymotrypsinlike or trypsin-like serine proteases. Using time lapse microscopy, we show here for the first time that malignant B cells, undergoing homotypic adhesion, actively communicate via ~ 5 nm wide temporary inter-cytoplasmic bridges. The formation of these channels is accompanied by the exchange of plasma membrane components. Moreover, the extent of plasma membrane swapping correlates with the extent of cell death induced by both anti-CD20 and anti-HLA DR antibodies. This data provide new insights into the potential mechanisms underlying mAb-induced cell death and may guide the rational design of more effective mAb therapy in B cell malignancies.

ABSTRACTMicrogels are hydrogel particles with micron and sub-micron diameters. They have beendeveloped, studied, and exploited for a broad range of applications because of their uniquecombination of size, soft mechanical properties, and controllable network properties. We havebeen using microgels to modulate the properties of surfaces to differentially control theirinteractions with tissue cells and bacteria. The long-term goal is to create biomaterials thatpromote healing while simultaneously inhibiting infection. Because poly(ethylene glycol) [PEG]is used in a number of FDA-approved products and has well-known antifouling properties, wework primarily with PEG-based microgels. We render these anionic either by copolymerizationwith monomeric acids or by blending with polyacids. Both methods produce pH-dependentnegative charge. Surfaces, both planar 2-D surfaces as well as topographically complex 3-Dsurfaces, can be modified using a hierarchy of non-line-of-sight electrostatic depositionprocesses that create biomaterials surfaces whose cell adhesiveness is modulated by a submonolayerof microgels. Average inter-microgel spacings of 1-2 microns exploit naturaldifferences between staphylococcal bacteria and tissue cells, which open the opportunity todifferentially control surface interactions with them based on length-scale effects. Afterdeposition, the microgels can be loaded with a variety of small-molecule, cationic antimicrobials.The details of loading depend on the relative sizes of the antimicrobials and the microgelnetwork structure as well as on the amount and spatial distribution of electrostatic charge withinboth the microgel and on the antimicrobial. The exposed surface between microgels can befurther modified by the adsorption of adhesion-promoting proteins such as fibronectin viaelectrostatic interaction. This approach combines a rich interplay of microgel structure andchemistry as a key component in a simple and translatable approach to modulate the surfaceproperties of next-generation biomaterials.

According to the cluster model of glassy polymers, in the amorphous state they are natural nanocomposites of two components of a loosely packed matrix and nanoclusters immersed in it, respectively playing the role of a matrix and filler in a natural composite. In this interpretation of the polymer, an important role is played by the dimensional effect of nanoclusters, identical to the specified effect of a nanofiller in an artificial nanocomposite, namely, a decrease in the size of both nanoclusters and dispersed particles leads to a sharp increase in the degree of amplification (modulus of elasticity) of the nanocomposite. In this paper, using parallel and sequential microcomposite models, upper and lower fractal estimates for the elastic modulus of the matrix are obtained and the synergistic effect of strengthening the elastic modulus of the nanocomposite as a whole as a superposition of the amplification effects from inorganic filler and from nanoclusters playing the role of filler of the loosely packed matrix is quantified. The object of research in this work is a packer - a device designed to disconnect two zones of the borehole and isolate the internal space of the production column from the impact of the borehole environment. The tightness of the packages is achieved thanks to sealing elements (SE), for the manufacture of which a composite with the composition is used: a mixture of synthetic butadiene nitrile and hydrogenated butadiene nitrile rubber (BNC + HBNC), vulcanizer, stabilizer, technological additives and copper nanoparticles. For the class of polymers under consideration, a rule has been developed for choosing the most preferred model from the above two micromechanical models at a given temperature. Keywords: oilfield equipment, synergetic effect, cluster model, natural nanocomposite, interfacial region, inter-component adhesion, loosely packed matrix.

4563 Background: Celecoxib inhibits tumorigenesis in many in vitro and in vivo models by anti-angiogenesis, induction of apoptosis, and inhibition of tumour cell proliferation and hypoxia. Methods: 45 cT1–2 prostate cancer patients were block randomized 2:1 to four weeks celecoxib 400mg b.d. or no drug prior to radical prostatectomy (RP). Tumour immunohistochemistry was performed for cell proliferation (Ki-67), angiogenesis (CD-31, VEGF, VEGF-R2), hypoxia (HIF-1), apoptosis (TUNEL), and COX-2. All scoring was performed blind by PS and a random 20% were validated blindly by an immunopathologist (SBF). In 19 patients (12 celecoxib-treated, 7 control), peri-operative peripheral zone biopsies were subjected to cDNA microarray analysis to identify differences in gene expression profiling (GEP) between the groups. Results: There was ‘substantial’ (kappa >0.6) or ‘almost perfect’ (kappa >0.8) inter-observer agreement in immunoscoring for all stains. Baseline scores were not significantly different between the celecoxib and control groups. In the celecoxib group, RP scores were significantly lower for Ki-67 (p = 0.036), and non-significantly lower for hypoxia (p = 0.15), KDR (p = 0.16), COX-2 (p = 0.19), microvessel density (p = 0.53), and VEGF (p = 0.83); tumour apoptosis was non-significantly higher (p = 0.26). MANOVA of the full model of stains showed that the difference between the two groups approached statistical significance (p = 0.058), and this was visualized with principal component analysis. GEP revealed that 76 genes were significantly differentially expressed between the celecoxib and control groups using uncorrected t-tests. In the celecoxib group, the tumour suppressor gene p73 and genes associated with protection against oxidative stress were significantly up-regulated; genes associated with cell adhesion were significantly down-regulated, consistent with a reduction in metastatic potential. Conclusions: Celecoxib appears to have marked anti-cancer effects on prostate tumours, most notably affecting cell cycle regulation, oxidative stress, and cell signalling. It may therefore be a promising agent in the management of prostate cancer and warrants further investigation. No significant financial relationships to disclose.

Objective: The mechanism of treatment-resistant hypertension (TRH) is not fully understood yet. However, studies suggest the involvement of vascular endothelial dysfunction and systemic inflammation as contributors to the pathogenesis. This study aims to identify any measurable differences in protein abundance between two groups of hypertensive adults, controlled hypertension (CH) and TRH, using proteomics analysis techniques. Design and method: The study samples were obtained from an existing observational cohort study involving CH and TRH groups; venous blood samples were previously stored at -80°C, and appropriate consenting and ethical approval was obtained. TRH was defined blood pressure (BP) of 140/90 mmHg or more, on 3 or more antihypertensive agents or controlled BP (less than140/90 mmHg) after taking 4 or more antihypertensive agents. The study was conducted in two phases: the discovery phase, where 60 samples of matched group's (CH, n=30, TRH n=30) Peripheral venous serum samples were initially depleted from the highly abundant proteins before undergoing trypsin digestion, this was followed by Liquid Chromatography Mass Spectrometry analysis. The validation phase included 140 candidates (CH n=81, TRH n=59). Results were statistically analysed using an independent T-test, P valve <0.05 was considered to be statistically significant. Gen Ontology (GO) description is used for the functional description of the proteins. Results: Full results analysis is still undergoing by the time this abstract is being submitted, however, 12 different proteins were found to be significantly different in their expression between the two groups: Alpha 1B glycoprotein, Leucine-rich alpha 2 glycoproteins, Inter alpha trypsin inhibitor heavy chain H3, Lumican, Complement component C9, Complement factor D, Contactin-1, Lysozyme C, Phospholipid transfer protein, and Vascular cell adhesion protein 1.Initial GO analysis suggests above proteins are involved in vascular integrity, endothelial function and inflammatory response. Conclusions: There are significant differences in the proteins expression between patients with TRH and CH. This may allow better understanding of TRH, and treatment strategies.

Wire Electrical Discharge Machining (WEDM) is a versatile process to generate intricate and complex shapes on conductive work material with high dimensional accuracy and surface finish. Since the process is stochastic, its input parameters play critical role for achieving desired accuracy and precision of the component. Inconel 718, High-Strength-Temperature-Resistant (HSTR) material, has wide applications in the field of aerospace, automobile, mould making and medical industries. Hence, machining of Inconel 718 using WEDM is a challenging task. Also experimentation on Inconel 718 with WEDM is costly as well as time consuming process. Therefore to study the behavior of WEDM process with different process parameters for effective and efficient operation, process modeling and simulation using appropriate software is highly essential. In the present investigation, a 3-D single spark finite element thermal model for WEDM process has been developed using ANSYS software. This model has some more realistic assumptions like heat flux following Gaussian distribution and spark radius as a function of time and energy. Plasma incident region is meshed by keeping elemental size equal to one tenth of entire plasma radius, so that exact ten elements can be fitted. Identified elements were thermally loaded by applying element wise different temperatures for getting more accurate temperature distribution profile. This profile was found to be having crater shape matching with earlier Finite Element Models (FEM) available in the literature. Along with the shape, it also helps to decide the elements having temperatures greater or equal to melting point leading to estimate Material Removal Rate (MRR). Later on single spark MRR can be used to estimate multi-discharge-MRR by calculating pulse rate. Model MRR is validated with the experimental MRR which show a very good agreement, but little variation. This variation in the modeling could possibly due to assumptions like no delay in ignition, non-deposition of recast layer (100% flushing efficiency), etc. The factors like incomplete flushing of debris and inter-electrode gap arcing cause the variation in machining conditions thus reducing the actual MRR. In the present investigation, the use of dielectric is considered only for convection, but in reality, it acts as an insulator, coolant and also as debris remover. Melting and vaporization of material is the main phenomena for material removal. Dielectric fluid partially removes the molten metal because at the same time, the molten metal is under very high pressure due to plasma channel. Its adhesive property resists the material removal. It is very difficult to incorporate all real effects in the model, however the obtained results in the present study show good agreement between model MRR and experimental MRR within 10% variation.