Structural and luminescent characteristics of YAG phosphors synthesized in the radiation field

YAG:Ce, YAGG:Ce ceramics were obtained by sintering the oxide powders in the radiation field. The results of investigations of the structure, composition and luminescence of ceramics are presented. The luminescence characteristics of powders exactly correspond to the phosphors luminescence used in practice obtained by solid-state synthesis methods. It has been established that in the used radiation exposure modes the main factor determining the efficiency of the synthesis is the ionization density

THERMOLUMINESCENCE OF Ga2O3 IRRADIATED BY HIGH-DOSE PULSED ELECTRON BEAM

The TL curves of pure gallium oxide ceramics synthesized in a stream of fast electrons are studied. It is established that the TL curve is the sum of two peaks with activation energies of 0.84 and 0.95 eV. The nature of the dose characteristics of the TL of the studied material is analyzed

Structural and luminescent characteristics of YAG phosphors synthesized in the radiation field

YAG:Ce, YAGG:Ce ceramics were obtained by sintering the oxide powders in the radiation field. The results of investigations of the structure, composition and luminescence of ceramics are presented. The luminescence characteristics of powders exactly correspond to the phosphors luminescence used in practice obtained by solid-state synthesis methods. It has been established that in the used radiation exposure modes the main factor determining the efficiency of the synthesis is the ionization density

Thermoluminescence of Magnesium Oxide Ceramics Obtained by the Method of Electron Beam Synthesis

The luminescent properties of MgO ceramics synthesized by the electron beam method were investigated. The luminescence centers were identified in the samples. The TL curves and dose characteristics of TL peaks excited by a pulsed electron beam (130 keV, 1.5–60 kGy) were analyzed

Structure and Luminescence of YAG:Ce, Gd, Ga Ceramics Synthesized Radiation Assistedmethod

The work shows the possibility of radiation synthesis based on YAG:Ce ceramics. Synthesis was carried out by sintering samples from oxide powders in the field of high-energy electron flow. The lattice structure of synthesized samples of YAG:Ce and YAGG:Ce ceramics was compared with standards.The work was carried out within the framework of the grant AP08052050 of the Ministry of Education and Science of the Republic of Kazakhstan. This research was supported by Tomsk Polytechnic University CE Program

As cast microstructures on the mechanical and corrosion behaviour of ZK40 modified with Gd and Nd additions

The microstructure of ZK40, ZK40 with 2 wt% of Nd and Gd (ZK40-2Nd and ZK40-2Gd, respectively) were investigated with optical, scanning and transmission electron microscopy, X-ray diffraction and Scanning Kelvin Probe Force Microscopy. The mechanical properties and the corrosion behaviour were correlated with the microstructure. The 2 wt% Gd addition enhanced the ductility, while the Nd addition resulted in deterioration in mechanical properties. The corrosion behaviour was also enhanced with the addition of Gd.The authors acknowledge the Deutsches Elektronen-Synchrotron (DESY) for the provision of facilities within the framework of proposal I-20130434. RHB acknowledges University of Sao Paulo for granting the fellowship ´Bolsa Empreendedorismo´. MM acknowledges the Alexander von Humboldt foundation for the provision of financial support in the form of post-doctoral fellowship

Interchromosomal Duplications on the Bactrocera oleae Y Chromosome Imply a Distinct Evolutionary Origin of the Sex Chromosomes Compared to Drosophila

BACKGROUND: Diptera have an extraordinary variety of sex determination mechanisms, and Drosophila melanogaster is the paradigm for this group. However, the Drosophila sex determination pathway is only partially conserved and the family Tephritidae affords an interesting example. The tephritid Y chromosome is postulated to be necessary to determine male development. Characterization of Y sequences, apart from elucidating the nature of the male determining factor, is also important to understand the evolutionary history of sex chromosomes within the Tephritidae. We studied the Y sequences from the olive fly, Bactrocera oleae. Its Y chromosome is minute and highly heterochromatic, and displays high heteromorphism with the X chromosome. METHODOLOGY/PRINCIPAL FINDINGS: A combined Representational Difference Analysis (RDA) and fluorescence in-situ hybridization (FISH) approach was used to investigate the Y chromosome to derive information on its sequence content. The Y chromosome is strewn with repetitive DNA sequences, the majority of which are also interdispersed in the pericentromeric regions of the autosomes. The Y chromosome appears to have accumulated small and large repetitive interchromosomal duplications. The large interchromosomal duplications harbour an importin-4-like gene fragment. Apart from these importin-4-like sequences, the other Y repetitive sequences are not shared with the X chromosome, suggesting molecular differentiation of these two chromosomes. Moreover, as the identified Y sequences were not detected on the Y chromosomes of closely related tephritids, we can infer divergence in the repetitive nature of their sequence contents. CONCLUSIONS/SIGNIFICANCE: The identification of Y-linked sequences may tell us much about the repetitive nature, the origin and the evolution of Y chromosomes. We hypothesize how these repetitive sequences accumulated and were maintained on the Y chromosome during its evolutionary history. Our data reinforce the idea that the sex chromosomes of the Tephritidae may have distinct evolutionary origins with respect to those of the Drosophilidae and other Dipteran families

Identification of microbial DNA in human cancer

<p>Abstract</p> <p>Background</p> <p>Microorganisms have been associated with many types of human diseases; however, a significant number of clinically important microbial pathogens remain to be discovered.</p> <p>Methods</p> <p>We have developed a genome-wide approach, called Digital Karyotyping Microbe Identification (DK-MICROBE), to identify genomic DNA of bacteria and viruses in human disease tissues. This method involves the generation of an experimental DNA tag library through Digital Karyotyping (DK) followed by analysis of the tag sequences for the presence of microbial DNA content using a compiled microbial DNA virtual tag library.</p> <p>Results</p> <p>To validate this technology and to identify pathogens that may be associated with human cancer pathogenesis, we used DK-MICROBE to determine the presence of microbial DNA in 58 human tumor samples, including brain, ovarian, and colorectal cancers. We detected DNA from Human herpesvirus 6 (HHV-6) in a DK library of a colorectal cancer liver metastasis and in normal tissue from the same patient.</p> <p>Conclusion</p> <p>DK-MICROBE can identify previously unknown infectious agents in human tumors, and is now available for further applications for the identification of pathogen DNA in human cancer and other diseases.</p