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Intrinsic defects in Bi2Te3 were analyzed using first-principles density functional theory calculations. The results demonstrated that antisite defects were dominant in both p- and n-type Bi2Te3. To investigate the characteristics of these defects, n-type Bi2(Te,Se)3 compounds were fabricated using powder prepared by high-energy ball milling and their electrical properties were examined. Electrical resistivity and the Seebeck coefficient increased with ball milling time. These changes in both properties were attributed to a reduction in the carrier concentration, which was supported by the Hall coefficient measurement. The antisite defects were found to be responsible for the changes in carrier concentration. Lattice parameter analysis supported the postulate that variations in the concentration of antisite defects were responsible for the changes in carrier concentration. These findings suggest that optimization of carrier concentration should be considered in the high-energy ball milling process, in which reductions in grain size are expected to improve thermoelectric properties.VC [ABSTRACT FROM AUTHOR]

In this study, the effect of Ag or Sb addition on the thermoelectric properties of PbTe including the Seebeck coefficient, the electrical resistivity, and the thermal conductivity, was studied in the temperature range from 323 to 723 K. The major carriers in the Ag-doped and the Sb-doped PbTe are holes and electrons, respectively. A degenerate semiconductor behavior in the electrical transport properties was observed in the Ag-doped, whereas the semi-metallic in the Sb-doped. It was suggested from the results of the Hall effect measurement and the Seebeck coefficient that the effective mass was significantly altered by the Sb-doping. The maximum dimensionless figure of merit, ZT, of Pb1-xAgxTe and Pb1-xSbxTe (x=0.1) alloys showed 0.27 and 0.62 at 723 K, respectively. Based on the analysis of the Seebeck coefficient of the Ag or the Sb-doped PbTe, the interaction between Ag and Sb in PbTe, as expected in the AgPbmSbTem+2 (LAST-m), may be supposed. [ABSTRACT FROM AUTHOR]

In this study, the thermoelectric properties of AgPbmSbTem+2 (LAST-m, m=12, 16, 18, 20, 22, and 26), including the Seebeck coefficient, the electrical resistivity, and the thermal conductivity, were studied in the temperature range from 323 to 773 K. The Seebeck coefficient and the electrical resistivity exhibited the behavior of a degenerate semiconductor. The measured results of the carrier concentration supported the conclusions of the electrical transport properties. The lowest electrical resistivity and the thermal conductivity were observed, which leads to the best thermoelectric performance in LAST-18 and the dimensionless figure of merit ZT value of 0.8 at 773 K. [ABSTRACT FROM AUTHOR]

Summary Reasons for performing study: The wild progenitors of the domestic horse were subject to natural selection for speed and stamina for millennia. Uniquely, this process has been augmented in Thoroughbreds, which have undergone at least 3 centuries of intense artificial selection for athletic phenotypes. While the phenotypic adaptations to exercise are well described, only a small number of the underlying genetic variants contributing to these phenotypes have been reported. Objectives: A panel of candidate performance-related genes was examined for DNA sequence variation in Thoroughbreds and the association with racecourse performance investigated. Materials and methods: Eighteen candidate genes were chosen for their putative roles in exercise. Re-sequencing in Thoroughbred samples was successful for primer sets in 13 of these genes. SNPs identified in this study and from the EquCab2.0 SNP database were genotyped in 2 sets of Thoroughbred samples (n = 150 and 148) and a series of population-based case-control investigations were performed by separating the samples into discrete cohorts on the basis of retrospective racecourse performance. Results: Twenty novel SNPs were detected in 3 genes: ACTN3, CKM and COX4I2. Genotype frequency distributions for 3 SNPs in CKM and COX4I2 were significantly (P<0.05) different between elite Thoroughbreds and racehorses that had never won a race. These associations were not validated when an additional (n = 130) independent set of samples was genotyped, but when analyses included all samples (n = 278) the significance of association at COX4I2 g.22684390C>T was confirmed (P<0.02). Conclusions: While molecular genetic information has the potential to become a powerful tool to make improved decisions in horse industries, it is vital that rigour is applied to studies generating these data and that adequate and appropriate sample sets, particularly for independent replication, are used. [ABSTRACT FROM AUTHOR]

Advances in high-throughput genotyping technologies have afforded researchers the opportunity to study ever-increasing numbers of SNP in animal genomes. However, many studies encounter difficulties in obtaining sufficient quantities of high-quality DNA for such analyses, particularly when the source biological material is limited or degraded. The recent development of in vitro whole-genome amplification approaches has permitted researchers to circumvent these challenges by increasing the amount of usable DNA in normally small-quantity samples. Here, we assess the performance of whole-genome amplification products generated from ovine genomic DNA using a high-throughput SNP genotyping platform, the newly developed Illumina ovineSNP50 BeadChip. Our results demonstrate a high genotype call rate for conventional genomic DNA and whole-genome amplified genomic DNA. The data also reveal an exceptionally high concordance rate (≥99%) between the genotypes generated from whole-genome amplified products and their conventional genomic DNA counterparts. This study supports the use of whole-genome amplification as a viable solution for the analysis of high-density SNP genotypic data using compromised or limited starting material. [ABSTRACT FROM AUTHOR]

In this work the analysis procedures of fission gas compositions and their isotopic distributions using a gas chromatography (GC) system and/or a quadrupole mass spectrometer (QMS) system were established, and their analysis results were reviewed in order to evaluate their analytical performance. Also, the accumulated data, up to now, regarding fission gas measurement were reviewed to discern any irradiation histories of the punctured fuel rods. A simple gas injection apparatus was designed and fabricated for the quantitative injection of a small volume of fission gas into the GC and the QMS system. With an appropriate temperature controlling of a molecular sieve 5A column, nitrogen, krypton and xenon of a mixture gas was clearly separated within 7 min. According to the analysis results, the relative standard deviation in the determination of fission gas compositions, krypton and xenon, by the GC analysis or by the QMS analysis was about 1%. Based on the review results of the isotopic ratios of krypton and xenon of the released fission gas, it is likely that no abnormally irradiated rods, i.e. defected rods, were included among the punctured rods. [ABSTRACT FROM AUTHOR]

Bovine tuberculosis (BTB), caused by Mycobacterium bovis, continues to pose a threat to livestock worldwide and, as a zoonotic infection, also has serious implications for human health. The implementation of comprehensive surveillance programmes to detect BTB has been successful in reducing the incidence of infection in many countries, yet BTB has remained recalcitrant to eradication in several EU states, particularly in Ireland and the UK. There are well-recognized limitations in the use of the current diagnostics to detect all infected animals and this has led to renewed efforts to uncover novel diagnostic biomarkers that may serve to enhance the performance of the tests. Studies of single immunological parameters have so far been unable to unlock the complexities of the immune response to mycobacterial infection. However, the development of high-throughput methods including pan-genomic gene expression technologies such as DNA microarrays has facilitated the simultaneous identification and analysis of thousands of genes and their interactions during the immune response. In addition, the application of these new genomic technologies to BTB has identified pathogen-associated immune response signatures of host infection. The objective of these investigations is to understand the changing profile of immune responses throughout the course of infection and to identify biomarkers for sensitive diagnosis, particularly during the early stages of infection. Transcriptional profiling via microarray and more recently via next-generation sequencing technologies may lead to the development of specific and sensitive diagnostics for M. bovis infection and will enhance the prospect of eradication of tuberculosis from cattle populations. [ABSTRACT FROM AUTHOR]

It is regarded that the spent resins from the water purification systems of moderator (MOD) and the primary coolant of the Canada deuterium uranium-pressurized heavy water reactor (CANDU-PHWR) are a unique waste, owing to their high 14C and gamma-emitting nuclides. In this work, 14C and 3H contents, anion and cation fractions and the predominant gamma-emitting nuclides of the spent resins from 4 units of CANDUPHWRs, were investigated. Also the chemical species of 14C of the spent resins were determined. For a simultaneous separation of 14C and 3H from the spent resins, the wet oxidation-16 wt% H2SO4 stripping process was utilized. The 14C and 3H activity concentration range of the spent resins of the nuclear power plant (NPP), 4 units of all CANDU-PHWR types, was 2.48E5 Bq/g ∼5.33E6 Bq/g, 1.29E5 Bq/g and ∼2.33E5 Bq/g, respectively. Among the analyzed spent resins, the highest 14C and 3H activity concentration was detected in units 4 and 3, respectively. It was found that more than 92% of the 14C activity concentration was retained on the anion resin and the predominant chemical species was inorganic 14C. It was revealed that the anion resin fraction of the spent resins from unit 1 and unit 2, was about 40% and that of unit 3 and unit 4 was around 60%. More than 80% of the total gamma-radioactivity concentration was associated with the cation fraction of the spent resin. The predominant gamma-emitting nuclide of the spent resin for unit 2 was 137Cs, a fission product, and that for unit 4 was 60Co, a corrosion product. [ABSTRACT FROM AUTHOR]

For miniaturisation and precision of electronic device, the new technologies such as photoimageable thick film process were combined with conventional thick film process, and constrained sintering with near zero shrinkage in the x and y direction has been proposed. In this research, photoimageable conductive paste for forming embedded components via constrained sintering by low temperature cofired ceramic (LTCC) technology was formulated. Afterwards, by optimising paste formulation, formation process of fine line and sintering method, miniaturised LTCC components especially embedded fine line inductors were fabricated and their properties such as line resolution, surface morphology and yield were investigated. As a result, embedded fine line inductors formed by constrained sintering with fine line resolution of 20 μm and yield over 90% were acquired. [ABSTRACT FROM AUTHOR]

It is impossible to detect 14C and 3H by direct methods such as γ-spectroscopy because they are pure b-emitters and thus they are classified as hard to measure nuclides (HTM). In this paper the analysis results of 14C and 3H in the low level radioactive wastes (LLWs), including spent ion exchange resin, evaporated bottom and sludge are presented. The LLWs were generated by three nuclear power plants (NPPs), in Korea all with pressurized water type reactors (PWRs). A simultaneous separation procedure for 14C and 3H in LLWs was established by wet oxidation-acid stripping. A liquid scintillation analyzer was used for the measurement of 14C and 3H. It was found that the recovery of 14C and 3H was 82-99 and 78-103%, respectively, by wet oxidation-acid stripping with diluted standard solutions. At the lowest injection of 14C and 3H, i.e., at 1.44 Bq for 14C and 1.22 Bq for 3H, the minimum detectable activity (MDA) of 14C and 3H was calculated as 0.88 and 0.78 Bq/g, respectively, for the minimum allowable sample weight, using wet oxidation and 16 wt% H2SO4 acid. By the wet oxidation-16 wt% H2SO4 stripping method no interfering nuclides were detected in the trapping solution of 14CO2 and the distillate of 3H. The activity concentration range of 14C in the analyzed samples, i.e., spent ion exchange resin, evaporated bottom and sludge, was 0.17-110,000, 8.4-1380 and 0.1-10,006 Bq/g, respectively, and that of 3H in the same was from no detectable to 769, 134-14,383 and 0.7-4820 Bq/g, respectively. [ABSTRACT FROM AUTHOR]

Equine mitochondrial DNA sequence variation was investigated in three indigenous Irish horse populations (Irish Draught Horse, Kerry Bog Pony and Connemara Pony) and, for context, in 69 other horse populations. There was no evidence of Irish Draught Horse or Connemara Pony sequence clustering, although the majority of Irish Draught Horse sequences (47%) were assigned to haplogroup D. Conversely, 31% of the Kerry Bog Pony sequences were assigned to the rare haplogroup E. In addition to the extant population analyses, ancient DNA sequences were generated from three out of four Irish archaeological specimens, all of which were assigned to haplogroup A. [ABSTRACT FROM AUTHOR]

The pathogenic potential and reproduction fitness ofMeloidogyne haplaon three species of medicinal plants,Angelica koreana,Peucedanum japonicumandAstragalus membranaceuswas determined in potted soil under greenhouse conditions. Three weeks old seedlings were inoculated with population density (Pi) of 1000; 2000; 3000; 4000; 5000 and 10000 juveniles (J2)/kg soil. A significant damage was observed in shoot and root length, weight and root-diameter of these plants by all Pi levels at 90-day postinoculation. Damage increased with increase in Pi up to 5000 J2/kg soil. At 5000 Pi caused 34.8, 34.1 and 33.3% reduction in root weight ofAng. koreana,P. japonicumandAst. membranaceus, respectively. Greater root gall severity was observed onAng. koreanaandP. japonicumthan onAst. membranaceusat all Pi levels. At 5000 Pi, root gall severity was 5.0, 5.0, and 3.0 onAng. koreana,P. japonicumandAst. membranaceus, respectively. Increasing rate of Pi exponentially reduced reproductive factor (Rf) ofM. haplaon all of these medicinal plants. However, Rf was higher onAng. koreanaandP. japonicumthan onAst. membranaceusat all Pi levels. The host status of these medicinal plants renders them unsuitable for their use in crop rotation system inM. hapla-infested fields. [ABSTRACT FROM AUTHOR]

Field experiments were conducted under natural as well as under vinyl house conditions to determine the effect of sowing time on development of anthracnose of safflower caused byColletotrichum acutatum, and to determine the level of resistance of seven cultivars. When crops were sown from March 1 to April 1; safflower anthracnose disease (SAD) incidence was low and increased slowly (0.7–10.9%) throughout the growing season. When sowing was delayed to April 15, disease incidence ranged between 29.5 and 48.5% from late May to July. Similarly, SAD severity and its severity index were higher (3.5 and 3.3, respectively) in plots sown on April 15 than in the plots sown from March 1 to April 1 (1.9–2.4 and 1.8–2.2, respectively). In contrast under vinyl houses that sheltered from rain, sowing time did not affect neither SAD, nor severity and severity index, which were 5.7–6.4%, 1.5–1.7 and 1.5–1.7, respectively. Among seven cultivars tested for resistance to SAD, Uisong-1, China-2 and India were highly susceptible (80–97%) under natural conditions followed by China-1, Uisan, Uisong-7 and Cheongsu (27–35%); however, under vinyl house conditions, SAD was lower (5.7–8.2%) and there was no significant difference between cultivars. [ABSTRACT FROM AUTHOR]

AbstractEight humpless cattle breeds from the Near East, three from Europe, one from West Africa and two zebu breeds from India were screened with 20 microsatellite loci. Breeds from the Near East revealed considerable levels of introgression from zebu cattle, which was apparent most in populations from the East and which declined in populations further West. This nonrandom pattern is suggestive of the introduction of zebu cattle from the East. Notwithstanding the overlay of zebu alleles, it was possible to demonstrate that Near Eastern cattle exhibited significantly higher levels of allelic diversity than breeds from other regions, which is consistent with the view that this region represents a primary domestication centre for Bos taurus cattle. The hypothesis that B. taurus and B. indicus cattle have separate domestic origins is also supported by the survey, a large genetic divergence being apparent between the nonhybrid taurine and zebu groups. [ABSTRACT FROM AUTHOR]

The SNF2/SWI2 ATPase/helicase family comprises proteins from a variety of species, which serve a number of functions, such as transcriptional regulation, maintenance of chromosome stability during mitosis, and various types of DNA repair. Several proteins with unknown functions are also included in this family. The number of genes that belong to this family is rapidly expanding, which makes it easier to analyze the common biological functions of the family members. This study was designed to clone the SNF2/SWI2 helicase-related genes from the fission yeast Schizosaccharomyces pombe in the hope that this would help to elucidate the common functions of the proteins in this family. The hrp1+ ( helicase- related gene from S. p ombe) gene was initially cloned by PCR amplification using degenerate primers based on conserved SNF2 motifs within the ERCC6 gene, which encodes a protein involved in DNA excision repair. The hrp1+ ORF codes for an 1373-amino acid polypeptide with a molecular mass of 159 kDa. Like other SNF2/SWI2 family proteins, the deduced amino acid sequence of Hrp1 contains DNA-dependent ATPase/7 helicase domains, as well as a chromodomain and a DNA-binding domain. This configuration is similar to that of mCHD1 (mouse chromo-ATPase/ helicase- DNA-binding protein 1), suggesting that Hrp1 is a S. pombe homolog of mCHD1, which is thought to function in altering the chromatin structure to facilitate gene expression. Northern blot analysis showed that the hrp1+ gene produces a 4.6-kb transcript, which reaches its maximal level just before the cells enter the exponential growth phase, and then decreases gradually. DNA-damaging agents, such as MMS, MNNG and UV, decrease the rate of transcription of hrp1+. Deletion of the hrp1+ gene resulted in accelerated cell growth. On the other hand, overexpression of Hrp1 caused a reduction in growth rate. These results indicate that hrp1+ may act as a negative regulator of cellular growth. [ABSTRACT FROM AUTHOR]

Quadratic voltage coefficient of capacitance (VCC) for ZrO2–SiO2 multilayered dielectric metal-insulator-metal capacitors depends strongly on the stacking sequence of the layered dielectrics. The quadratic VCC of an optimized SiO2/ZrO2/SiO2 stack and ZrO2/SiO2/ZrO2 stack were +42 and -1094 ppm/V2, respectively, despite the same total SiO2 and ZrO2 dielectric thickness in the stack. The observed difference in quadratic VCC depending on dielectric stacking sequence is explained by taking into account both the interface and bulk dielectric responses to the applied voltage. [ABSTRACT FROM AUTHOR]

High electron mobility transistors (HEMTs) with InAs/InGaAs composite channel were fabricated by employing low damage, highly selective Ne-based atomic layer etching (ALET) for the dry gate recess process. Ne-based ALET exhibited very high etch selectivity of InP over InAlAs which is suitable for dry gate recess process removing InP etch stop layer on top of InAlAs Schottky barrier layer. The plasma induced damage on the exposed InAlAs surface due to the ALET was much lower than that due to the conventional Ar-based reactive ion etching (RIE), which was verified by atomic force microscopy and Hall measurements. For further comparison, dc characteristics were compared for the two types of 0.3 μm HEMTs fabricated by utilizing ALET and conventional RIE during the dry gate recess processes. [ABSTRACT FROM AUTHOR]

Highly selective, low damage atomic layer etching (ALET) technology was developed for dry gate recess during the fabrication of InGaAs/InP/InAlAs high electron mobility transistors lattice matched to InP substrates. Etching characteristics of InP layer on top of InAlAs layer and the surface chemistry of the exposed InAlAs layer were investigated by utilizing angular resolved x-ray photoelectron spectroscopy. Finally, InAlAs Schottky diodes were fabricated by utilizing chlorine-based ALET technology and conventional Ar-based dry recess and their electrical characteristics were compared. By using the ALET, the etch selectivity as high as 70:1 was achieved for InP over InAlAs heterostructures and the stoichiometric modification of InAlAs was observed to be negligible after the recess etch process. Schottky diodes fabricated after the ALET exhibited the lower ideality factor and the higher Schottky barrier height compared to those fabricated with Ar-based plasma etching. [ABSTRACT FROM AUTHOR]

In this study, the atomic layer etching characteristics and the etch mechanism of (100) InP as functions of Cl2 pressure and Ne neutral beam irradiation dose were investigated. When Cl2 pressure and Ne neutral beam irradiation dose were lower than the critical values of 0.4 mTorr and 7.2×1015 at./cm2 cycle, respectively, the InP etch rate (Å/cycle) and the InP surface roughness varied with Cl2 pressure and Ne neutral beam irradiation dose. However, when the Cl2 pressure and Ne neutral beam irradiation dose were higher than the critical values, the InP etch rate remained as 1.47 Å/cycle, corresponding to one monolayer per cycle, and the surface roughness and the surface stoichiometry remained similar to those of InP before etching. [ABSTRACT FROM AUTHOR]

In this study, the etch characteristics of ZrOx and the etch selectivity to Si were investigated using BCl3/C4F8 plasmas. The etching mechanism was also investigated. Increasing the C4F8 percentage to 4% formed a C–F polymer layer on the silicon surface due to the increased flux ratio of CFx/F to the substrate, while no such C–F polymer was formed on the ZrOx surface due to the removal of carbon from CFx by the oxygen in ZrOx. By using 3–4% C4F8 in the BCl3/C4F8 mixture, infinite etch selectivity of ZrOx to silicon and photoresist could be obtained while maintaining the ZrOx etch rate above 400 Å/min. [ABSTRACT FROM AUTHOR]