74 research outputs found
Elicitin-Mediated Plant Resistance
Qualitative transcriptional regulatory sequences functional in plants, plant tissue and in plant cells for inducible gene expression and quantitative transcriptional regulatory sequences for increasing the transcriptional expression of downstream genetic information in plants, plant tissue and plant cells are disclosed. Also disclosed are methods and recombinant DNA molecules for improving the disease resistance of transgenic plants, especially wherein an inducible promoter controls the expression of a protein capable of evoking the hypersensitive response in a plant
Pathogen- or Elicitor-Inducible Transcription Regulatory Element from the Tobacco 5-EPI-Aristolochene Synthase Gene and Plants Transformed Therewith
A tobacco epi-5-aristolochene synthase transcriptional regulatory element functional in plants, plant tissue and in plant cells for pathogen inducible gene expression and a method for increasing the transcriptional expression of downstream genetic information in plants, plant tissue and plant cells are disclosed
Transcriptional Silencing Elements and Their Binding Factors
The invention features an isolated gene silencing regulatory element that includes 5\u27 TACNNTAC 3\u27. Vectors, transgenic plants and seeds thereof that include such a gene silencing regulatory element are also disclosed. The invention further provides methods of decreasing the transcription of a DNA sequence in a transgenic plant using the isolated gene silencing regulatory element
Recommended from our members
New testing and calculation method for determination viscoelasticity of optical glass
Viscoelastic properties of glass within molding temperatures, such as shear relaxation modulus and bulk relaxation modulus, are key factors to build successful numerical model, predict forming process, and determine optimal process parameters for precision glass molding. However, traditional uniaxial compression creep tests with large strains are very limited in obtaining high-accuracy viscoelastic data of glass, due to the declining compressive stress caused by the increasing cross-sectional area of specimen in testing process. Besides, existing calculation method has limitation in transforming creep data to viscoelasticity data, especially when Poisson's ratio is unknown at molding temperature, which further induces a block to characterize viscoelastic parameter. This study proposes a systematic acquisition method tbr high-precision viscoelastic data, including creep testing, viscoelasticity calculation, and finite element verification. A minimal uniaxial creep testing (MUCT) method based on thermo-mechanical analysis (TMA) instrument is first built to obtain ideal and accurate creep data, by keeping compressive stress as a constant. A new calculation method on viscoelasticity determination is then proposed to derive shear relaxation modulus without the need of knowing bulk modulus or Poisson's ratio, which, compared with traditional method, extends the application range of viscoelasticity calculation. After determination, the obtained viscoelastic data are further incorporated into a numerical simulation model of MUCT to verify the accuracy of the determined viscoelasticity. Base on the great consistence between simulated and measured results (uniaxial creep displacement), the proposed systematic acquisition method can be used as a high accuracy viscoelasticity determination method.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Fabrication of small aspheric moulds using single point inclined axis grinding
Single point inclined axis grinding techniques, including the wheel setting, wheel-workpiece interference, error source determination and compensation approaches, were studied to fabricate small aspheric moulds of high profile accuracy. The interference of a cylindrical grinding wheel with the workpiece was analysed and the criteria for selection of wheel geometry for avoiding the interference was proposed. The grinding process was performed with compensation focused on two major error sources, wheel setting error and wheel wear. The grinding results showed that the compensation approach was efficient and the developed grinding process was capable to generate small aspheric concave surfaces on tungsten carbide material with a profile error of smaller than 200. nm in PV value after two to three compensation cycles
Dextran and Polymer Polyethylene Glycol (PEG) Coating Reduce Both 5 and 30 nm Iron Oxide Nanoparticle Cytotoxicity in 2D and 3D Cell Culture
Superparamagnetic iron oxide nanoparticles are widely used in biomedical applications, yet questions remain regarding the effect of nanoparticle size and coating on nanoparticle cytotoxicity. In this study, porcine aortic endothelial cells were exposed to 5 and 30 nm diameter iron oxide nanoparticles coated with either the polysaccharide, dextran, or the polymer polyethylene glycol (PEG). Nanoparticle uptake, cytotoxicity, reactive oxygen species (ROS) formation, and cell morphology changes were measured. Endothelial cells took up nanoparticles of all sizes and coatings in a dose dependent manner, and intracellular nanoparticles remained clustered in cytoplasmic vacuoles. Bare nanoparticles in both sizes induced a more than 6 fold increase in cell death at the highest concentration (0.5 mg/mL) and led to significant cell elongation, whereas cell viability and morphology remained constant with coated nanoparticles. While bare 30 nm nanoparticles induced significant ROS formation, neither 5 nm nanoparticles (bare or coated) nor 30 nm coated nanoparticles changed ROS levels. Furthermore, nanoparticles were more toxic at lower concentrations when cells were cultured within 3D gels. These results indicate that both dextran and PEG coatings reduce nanoparticle cytotoxicity, however different mechanisms may be important for different size nanoparticles
Title: Fabrication of small aspheric moulds using single point inclined axis grinding Fabrication of small aspheric moulds using single point inclined axis grinding Fabrication of small aspheric moulds using single point inclined axis grinding
Abstract Single point inclined axis grinding techniques, including the wheel setting, wheel-workpiece interference, error source determination and compensation approaches, were studied to fabricate small aspheric moulds of high profile accuracy. The interference of a cylindrical grinding wheel with the workpiece was analysed and the criteria for selection of wheel geometry for avoiding the interference was proposed. The grinding process was performed with compensation focused on two major error sources, wheel setting error and wheel wear. The grinding results showed that the compensation approach was efficient and the developed grinding process was capable to generate small aspheric concave surfaces on tungsten carbide material with a profile error of smaller than 200 nm in PV value after two to three compensation cycles
Polishing characteristics and mechanism in magnetorheological planarization using a permanent magnetic yoke with translational movement
Translational movement was integrated into a magnetorheological planarization process that uses a permanent magnet yoke with a straight air gap as magnetic source in order to improve surface planarity. The effects of the process conditions, including stroke and velocity of the translational movement, work and excitation gaps and concentration of carbonyl iron particles, on the polishing forces, surface roughness and volumetric removal rate were systematically investigated. The results showed that translational movement had insignificant effect on the polished surface finish, but considerably improved the surface planarity. The surface quality and volumetric removal rate were found to be affected by carbonyl iron particles concentration, and work and excitation gaps. Based on the parametric study, theoretical and empirical models were established for predicting the polishing forces, surface roughness and volumetric removal rate in this magnetorheological process
A comparative study on magnetorheological planarization using modified magnetic yokes and brick magnet
The geometric shape of magnets was modified to improve surface planarity and polishing efficiency in magnetorheological planarization. Two modified permanent magnetic yokes and a magnetic brick were used as excitation units of magnetic field. Stress analysis indicated that the polishing stress of the horizontal magnetic yoke was smaller than that of the brick magnet, but greater than that of the sloping yoke. The performances of MR planarizations, including removal rate, roughness, and planarity, of the three magnetic sources were also compared. The results showed that the sloping yoke produced the lowest surface finish of 0.6\ua0nm in R and the best planarity of 0.7\ua0μm in PV, and the brick magnet provided the highest removal efficiency
- …