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51.
Indu Upadhyaya Abhinav Upadhyay Anup Kollanoor-Johny Michael J. Darre Kumar Venkitanarayanan 《International journal of molecular sciences》2013,14(5):10608-10625
Salmonella Enteritidis (SE) is a major foodborne pathogen in the United States and one of the most frequently reported Salmonella serotypes globally. Eggs are the most common food product associated with SE infections in humans. The pathogen colonizes the intestinal tract in layers, and migrates to reproductive organs systemically. Since adhesion to and invasion of chicken oviduct epithelial cells (COEC) is critical for SE colonization in reproductive tract, reducing these virulence factors could potentially decrease egg yolk contamination. This study investigated the efficacy of sub-inhibitory concentrations of three plant-derived antimicrobials (PDAs), namely carvacrol, thymol and eugenol in reducing SE adhesion to and invasion of COEC, and survival in chicken macrophages. In addition, the effect of PDAs on SE genes critical for oviduct colonization and macrophage survival was determined using real-time quantitative PCR (RT-qPCR). All PDAs significantly reduced SE adhesion to and invasion of COEC (p < 0.001). The PDAs, except thymol consistently decreased SE survival in macrophages (p < 0.001). RT-qPCR results revealed down-regulation in the expression of genes involved in SE colonization and macrophage survival (p < 0.001). The results indicate that PDAs could potentially be used to control SE colonization in chicken reproductive tract; however, in vivo studies validating these results are warranted. 相似文献
52.
Effect of γ‐irradiation on glycolysis of PET waste and preparation of ecofriendly coatings using bio‐based and recycled materials 下载免费PDF全文
Vandana Jamdar Mukesh Kathalewar R.N. Jagtap Kumar Abhinav Dubey Anagha Sabnis 《Polymer Engineering and Science》2015,55(11):2653-2660
Recycling of postconsumer poly (ethylene terephthalate) (PET) is a worldwide concern due to large increasing volume of these materials produced by society. In the present study, we report the effect of gamma irradiation on degradation of PET and its subsequent effect on glycolysis by using excess ethylene glycol (EG). The results as analyzed by molecular weight determination showed that extent of depolymerization of PET were dose dependent. The doses of 30, 50, 70, and 100 kGy resulted in decrease in the molecular weight by about 15%, 25%, 30%, and 40% respectively. The irradiated waste PET samples were further subjected to glycolysis using EG by conventional and microwave method which resulted in increased yield of monomeric product, bis (2‐hydroxyethylterephthalate) (BHET). The recycled material, BHET, was then used in combination with bio‐based monomers to prepare a new eco‐friendly polyester polyol which was analyzed for hydroxyl, saponification, acid value and further characterized by FTIR, 1HNMR, and GPC techniques for molecular weight determination. Polyurethane coatings were prepared from the polyester polyol and various commercial polyisocyanate curing agents. The coated films were evaluated for their performance properties. Thermal properties of coatings were investigated by differential scanning calorimetry and thermogravimetric analysis. POLYM. ENG. SCI., 55:2653–2660, 2015. © 2015 Society of Plastics Engineers 相似文献
53.
Singh Sukhanidhan Yadav Abhinav Kumari Manisha Sarun P. M. 《Journal of Materials Science: Materials in Electronics》2022,33(12):9395-9402
Journal of Materials Science: Materials in Electronics - Calcium copper titanate (CCTO) ceramic is prepared by conventional solid-state reaction (SSR) technique. Sintering of manufactured CCTO... 相似文献
54.
Madan Lal Mamta Shandilya Ajith S. Kumar Radheshyam Rai Swapna S. Nair Ratnakar Palai 《Journal of Materials Science: Materials in Electronics》2018,29(1):80-85
Multiferroic ceramic composites of (1?x)Ba0.96Ca0.04TiO3–(x)ZnFe2O4 (BCT-ZF) were prepared from ferroelectric (FE) barium calcium titanate (BCT) and ferromagnetic (FM) zinc ferrite (ZF) by using the solid state reaction method with different mol% fractions of x (x?=?0.1 and 0.2). The preliminary structural studies carried out by X-ray diffraction at room temperature reveals that the samples have a tetragonal structure along with the cubic spinel ferrite phase. Raman spectra of the composites also confirm the existence of BCT phase and ZF phase. The room temperature ferroelectric polarization measurements as a function of magnetic field show the existence strong magnetoelectric coupling of 10.85 (mV/(cm.Oe). 相似文献
55.
Bhavana Bhadriraju Mohammed Saad Faizan Bangi Abhinav Narasingam Joseph Sang-Il Kwon 《American Institute of Chemical Engineers》2020,66(11):e16980
Over the past few decades, several data-driven methods have been developed for identifying a model that accurately describes the process dynamics. Lately, sparse identification of nonlinear dynamics (SINDy) has delivered promising results for various nonlinear processes. However, at any instance of plant-model mismatch or process upset, retraining the model using SINDy is computationally expensive and cannot guarantee to catch up with rapidly changing dynamics. Hence, we propose operable adaptive sparse identification of systems (OASIS) framework that extends the capabilities of SINDy for accurate, automatic, and adaptive approximation of process models. First, we use SINDy to obtain multiple models from historical data for varying input settings. Next, using these models and their training data, we build a deep neural network that is incorporated in a model predictive control framework for closed-loop operation. We demonstrate the OASIS methodology on the identification and control of a continuous stirred tank reactor. 相似文献
56.
A novel optimization approach for minimum cost design of trusses 总被引:1,自引:0,他引:1
This paper describes new optimization strategies that offer significant improvements in performance over existing methods for bridge-truss design. In this study, a real-world cost function that consists of costs on the weight of the truss and the number of products in the design is considered. We propose a new sizing approach that involves two algorithms applied in sequence – (1) a novel approach to generate a “good” initial solution and (2) a local search that attempts to generate the optimal solution by starting with the final solution from the previous algorithm. A clustering technique, which identifies members that are likely to have the same product type, is used with cost functions that consider a cost on the number of products. The proposed approach gives solutions that are much lower in cost compared to those generated in a comprehensive study of the same problem using genetic algorithms (GA). Also, the number of evaluations needed to arrive at the optimal solution is an order of magnitude lower than that needed in GAs. Since existing optimization techniques use cost functions like those of minimum-weight truss problems to illustrate their performance, the proposed approach is also applied to the same examples in order to compare its relative performance. The proposed approach is shown to generate solutions of not only better quality but also much more efficiently. To highlight the use of this sizing approach in a broader optimization framework, a simple geometry optimization algorithm that uses the sizing approach is presented. This algorithm is also shown to provide solutions better than the existing results in literature. 相似文献
57.
A new parallel dynamic unstructured grid DSMC method is presented in this paper. The code developed has been applied to the simulation of thin film deposition over microstructures. Surface deformation in such cases poses a challenge for accurate evaluation of gas flow due to the fact that the deposited film thickness is comparable to the feature size. In this study a method is developed to move the mesh at run time. Since in parallel simulation each partition moves independently of the others, a parallel version of moving mesh is proposed to synchronize the displacement of the neighboring partitions, so that there is a smooth transition from one partition to another. An efficient tool for tracking particles during simulation is also presented. Furthermore, the influence of parameters, such as sticking coefficient and aspect ratio on step coverage for a 1m wide trench by sputter deposition was studied. The results showed that the step coverage deteriorated with increasing sticking coefficient and aspect ratio. 相似文献
58.
Yogesh Singh Chauhan Costin Anghel Francois Krummenacher Christian Maier Renaud Gillon Benoit Bakeroot Bart Desoete Steven Frere Andre Baguenier Desormeaux Abhinav Sharma Michel Declercq Adrian Mihai Ionescu 《Solid-state electronics》2006,50(11-12):1801-1813
In this work, we present for the first time, a highly scalable general high voltage MOSFET model, which can be used for any high voltage MOSFET with extended drift region. This model includes physical effects like the quasi-saturation, impact-ionization and self-heating, and a new general model for drift resistance. The model is validated on the measured characteristics of two widely used high voltage devices in the industry i.e. LDMOS and VDMOS devices, and implemented on commercial circuit simulators like SABER (Synopsys), ELDO (Mentor Graphics), Spectre (Cadence) and UltraSim (Cadence). The accuracy of the model is better than 10% for DC I–V and g–V characteristics and shows good behavior for all capacitances which are unique for these devices showing peaks and shift of peaks with bias variation. The model also exhibits excellent scalability with transistor width, drift length, number of fingers and temperature. 相似文献
59.
This paper is focused on developing experimentally validated models of piping components as well as a complete two story piping system. The damage in a piping system is characterized in terms of “First Leakage” based on the observations made in laboratory experiments. Monotonic and cyclic testing for pipe components of various sizes shows that the limit-state for leakage is governed predominantly by flexural deformations at the threaded and groove fit T-joints. As a first step in the validation process, the nonlinear models for the flexural behavior of T-joints are reconciled with the experimental results. Next, the validated component models are incorporated in the piping model for a two story sprinkler system. The system level piping model is then integrated with ceiling systems that interact with sprinkler heads. The complex piping ceiling system model is validated by comparison with the corresponding experimental data. 相似文献
60.
Temperature derivative spectroscopy (TDS), a type of relaxation spectroscopy, is a powerful tool to study protein dynamics (Berendzen, J.; Braunstein, D. Proc. Natl. Acad. Sci. U. S. A. 1990, 87, 1). We developed the version of temperature derivative spectroscopy to monitor kinetics of autoxidation of cytochromes P450 and applied it to study the properties of the oxy-ferrous complex of a human membrane bound P450, CYP19A1 (aromatase), and that of a bacterial soluble P450, CYP101 when bound with their most common substrates, androstenedione (AD) and camphor, respectively. TDS extends the panel of methods that can be used to monitor heme protein kinetics, providing a rapid measurement technique and enabling measurement of the autoxidation rate over a wide range of temperatures, yielding the activation energy as well as absolute reaction rate in a single experiment. 相似文献