Identification of differentially expressed genes in seeds of two Brassica napus mutant lines with different oleic acid content

The regulation of seed oleic acid synthesis in rapeseed is largely unknown. In this study, gene expression pattern during seed development between two Brassica napus mutants was compared. Using immature seeds 27 days after pollination, differentially expressed cDNA clones were identified bysubtractive suppression hybridization (SSH). A total of 480 cDNA clones corresponding to 88 genes were found up-regulated and 18 genes down-regulated in seeds with high oleic acid content. Most ofthe differentially expressed genes are related to metabolism and regulation. The possible role of these genes in seeds was discussed. Further analysis of the function of these genes may provide novel targets for manipulation of fatty acid composition in rapeseed

Identification of potential drug resistant mutations in HIV-1 infected patients with long-term undetectable viral load after receiving HAART

This journal suppl. entitled: HIV DART 2010 ... Final Program and Abstract BookSession - Drug Resistance and ModelingConference Theme: Frontiers in drug development for in antiretroviral therapiesBACKGROUND: This study aimed to identify potential drug resistant mutations in proviral DNA in HIV patients with long-term undetectable viral load after receiving HAART. METHOD: Peripheral blood mononuclear cells (PBMC) were collected from 45 patients twice per year from 2005 to 2009. These patients have been receiving effective highly active antiretroviral therapy …published_or_final_versio

Study on the influence of temperature on the surface asperity in micro cross wedge rolling

When the common deformation processes are scaled down to micro/meso dimensions, size effect is the particular phenomena in microforming, which is related to the dominant influence of single grains inside the micropart. The conventional cross wedge rolling (CWR) is introduced into the micro scale in order to take the advantages of CWR. The micro cross wedge rolling (MCWR) has to confront with the phenomena of size effect that occurs in the common microforming processes inevitably. One of the approaches to compensate size effect is to increase the deforming temperature. An increased formability is achieved because more slip systems of polycrystal metal are activated at the elevated temperature. This reduces the anisotropic material behavior resulting in a more homogeneous forming with improved reproducibility. In this study, a YAG laser beam is applied to heat the workpiece. Finite element model (FEM) associated with a material constitutive formulation considering dislocation mechanics is set up to simulate the MCWR of pure copper utilizing the laser heating. The surface asperity as an indication of material heterogeneity in micro scale is quantitatively analysed. The simulation results show a good agreement with experimental results in terms of the surface asperity. © 2013 AIP Publishing LLC

The virtual organizing process—A critical tool for enterprise competitiveness in the information era

The term virtual enterprise has generated considerable confusion because of its rather liberal interpretation. This paper argues that the successful establishment of a virtual enterprise is mainly dependent on the virtual organizing processes of an enterprise\u27s strategies ( VOPES), rather than on the actual manifested transformation of the whole into a single virtual organization. A three-dimensional dynamic framework for VOPES is presented, with the aim of providing a coherent model for positioning the various virtual organizing strategies, and at the same time giving VOPES dynamic tendencies towards market negotiation, co-operation, co-ordination and collaboration. To achieve a competitive advantage, the top management of an enterprise operating in an intense information environment can organize their enterprise virtually by using the three-dimensional framework of: virtual customer relationship, virtual outsourcing, and virtual knowledge and expertise. The generic IT architecture of VOPES is also described and discussed

Phase transformation behaviour of porous NiTi alloys fabricated by capsule-free hot isostatic pressing

Differential scanning calorimetry (DSC) was used to characterize the phase transformation behaviour of porous Ni50Ti50 alloys fabricated by capsule-free hot isostatic pressing (CF-HIP) with different cold compaction pressures. Experimental results reveal that a multi-stage martensitic transformation (MST) exists in the sintered porous NiTi alloys on cooling while the reverse transformation upon heating is either a single or two-stage phase transformation. The DSC thermal analysis indicates that the cold compaction pressure has great effect on the subsequent transformation temperatures. Generally, the phase transformation temperatures of porous NiTi alloys with lower cold compaction pressure are higher than those compacted with higher pressure. With increase in the annealing time, the transformation temperatures increase quickly when the cold compaction pressure was 150MPa. On the other hand, the transformation temperatures change only slightly when the cold compaction pressure was varied from 300MPa to 400MPa. These phenomena can be attributed to the combined effect of larger plastic deformation with higher dislocations density produced by cold compaction and the precipitation of the second phase in the porous NiTi alloys.published_or_final_versio

DNA regulatory motif selection based on support vector machine (SVM) and its application in microarray experiment of Kashin-Beck disease

Conserved DNA sequences are essential to investigate the regulation and expression of nearby genes. The conserved regions can interact with certain proteins and can potentially determine the transcription speed and amount of the corresponding mRNA in gene replication process. In this paper, motifs of coexpressed genes of microarray experiments were explored with discovery algorithms. Then a selection algorithm based on support vector machine (SVM) was applied to identify those motifs which mostly influenced gene expression. This method combined the advantages from both matrix based motif finding and functional motif selection. When applied to Kashin-Beck disease (KBD), this method identified 9 motifs, and revealed that some motifs may be related to the immune reactions. In addition, we suggested that the methods used could be applied to other microarray experiments to explore the underlying relationships between motif types and gene functions.Key words: Support vector machine (SVM), microarray, motif discovery, gene regulation, Kashin-Beck disease

Biomimetic deposition of apatite on surface chemically modified porous NiTi shapememory alloy

Porous NiTi shape memory alloy (SMA) with 48% porosity and an average pore size of 50800 μm was synthesized by capsule-free hot isostatic pressing (CF-HIP). To enhance the surface bioactivity, the porous NiTi SMA was subjected to H"2O"2 and subsequent NaOH treatment. Scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses revealed that a porous sodium titanate (Na"2TiO"3) film had formed on the surface of the porous NiTi SMA. An apatite layer was deposited on this film after immersion in simulated body fluid at 37°C, while no apatite could be found on the surface of the untreated porous NiTi SMA. The formation of the apatite layer infers that the bioactivity of the porous NiTi SMA may be enhanced by surface chemical treatment, which is favorable for its application as bone implants. © 2008 World Scientific Publishing Company.postprin

Magnetic field effects on the electroluminescence of organic light emitting devices: A tool to indicate the carrier mobility

The magnetoelectroluminescence (MEL) of organic light emitting devices with a N, N′ -bis(l-naphthyl)- N, N′ -diphenyl- 1, l′ -biphentl- 4, 4′ -diamine:tris-(8-hydroxyquinoline) aluminum (NPB: Alq 3) mixed emission layer (EML) has been investigated. We find that MEL is maximized when the volume ratio of NPB of the mixed EML reaches 30% and the EML thickness is 40 nm. The features of MEL under various magnetic field strengths are insensitive to the change in EML thickness and mixing ratio. Meanwhile, MEL has a close relationship with the carrier mobility. We have conducted a theoretical study to further verify the relationship. Our experimental and theoretical results confirm that MEL can function as a tool to indicate the mobility. © 2010 American Institute of Physics.published_or_final_versio

Self-Organized Ni Nanocrystal Embedded in BaTiO3 Epitaxial Film

Ni nanocrystals (NCs) were embedded in BaTiO3 epitaxial films using the laser molecular beam epitaxy. The processes involving the self-organization of Ni NCs and the epitaxial growth of BaTiO3 were discussed. With the in situ monitoring of reflection high-energy electron diffraction, the nanocomposite films were engineered controllably by the fine alternation of the self-organization of Ni NCs and the epitaxial growth of BaTiO3. The transmission electron microscopy and the X-ray diffraction characterization confirmed that the composite film consists of the Ni NCs layers alternating with the (001)/(100)-oriented epitaxial BaTiO3 separation layers

New plasma surface-treated memory alloys: Towards a new generation of "smart" orthopaedic materials

This paper describes the corrosion resistance, surface mechanical properties, cyto-compatibility, and in-vivo performance of plasma-treated and untreated NiTi samples. Nickel-titanium discs containing 50.8% Ni were treated by nitrogen and carbon plasma immersion ion implantation (PIII). After nitrogen plasma treatment, a layer of stable titanium nitride is formed on the NiTi surface. Titanium carbide is also found at the surface after carbon plasma implantation. Compared to the untreated samples, the corrosion resistances of the plasma PIII samples are better by a factor of five and the surface hardness and elastic modulus are better by a factor of two. The concentration of Ni leached into the simulated body fluids from the untreated samples is 30 ppm, whereas that from the plasma-treated PIII are undetectable. Although there is no significant difference in the ability of cells to grow on either surface, bone formation is found to be better on the nitrogen and carbon PIII sample surfaces at post-operation 2 weeks. All these improvements can be attributed to the formation of titanium nitride and titanium carbide on the surface. © 2007 Elsevier B.V. All rights reserved.postprin