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Larson-Miller (LM) and Orr-Sherby-Dorn (OSD) parameters are widely used when formulating and predicting creep rupture life t r . The LM constant C and the activation energy Q in the OSD parameter characterize temperature dependence of t r . Q = Q LSD ( Q LSD : activation energy for lattice self-diffusion) and C = 20 are often assumed in the formulation. Creep rupture datasets of 11 heats of nickel alloy A617, 304H and 304J1 stainless steels, 6 heats of A3004N aluminum alloy and four Mg-Al alloys are formulated with the parameters for determining C and Q of each dataset. Based on the correlation between C and Q among similar materials, it is discussed what is the C value equivalent to Q = Q LSD . It is also examined how the C value changes with melting temperature of the material. The value of C equivalent to Q = Q LSD varies from 14 to 9.5 depending on average values of log(rupture life) and of reciprocal temperature of the dataset. These values of C point out that C = 20 is not equivalent to Q = Q LSD . The equivalent C values are similar in all the materials independently of their melting temperatures. [ABSTRACT FROM AUTHOR]

Abstract: The effect of boron and nitrogen on the microstructure evolution in heat affected zone (HAZ) of 9Cr steel during simulated heating and on the Type IV fracture in welded joints has been investigated at 650°C. Gr.92 exhibits a significant decrease in time to rupture after thermal cycle to a peak temperature near AC3, while the creep life of Gr.92N, subjected to only normalizing but no tempering, and 9Cr-boron steel is substantially the same as that of the base metals. In Gr.92 after AC3 thermal cycle, very few precipitates are formed along PAGBs in the fine-grained microstructure. In the P92N and 9Cr-boron steel after AC3 heat cycle, on the other hand, not only PAGBs but also lath and block boundaries are covered by M23C6 carbides in the coarse-grained microstructure. It is concluded that the degradation in creep life in Gr.92 after the AC3 thermal cycle is not caused by grain refinement but that the reduction of boundary and sub-boundary hardening is the most important. Soluble boron is essential for the change in α/γ transformation behavior during heating and also for the suppression of Type IV fracture in welded joints. Newly alloy-designed 9Cr steel with 160ppm boron and 85ppm nitrogen exhibits much higher creep rupture strength of base metal than P92 and also no Type IV fracture in welded joints at 650°C. [ABSTRACT FROM AUTHOR]

Abstract: Bovine growth hormone (bGH) gene polymorphism of leucine (Leu)-threonine (Thr) (allele A), valine (Val)-Thr (allele B), and Val-methionine (Met) (alleleC) at codons 127 and 172 was shown to relate with carcass trait variations in Japanese Black cattle. In this study, 10-mo-old Japanese Black heifers with growth hormone (GH) genotypes AA, AB, BB, AC, BC, and CC (N=141) were compared for basal GH, insulin-like growth factor-1 (IGF-1), insulin, ghrelin, glucose, and nonesterified fatty acid (NEFA) concentrations. Growth hormone release was also measured as response to growth hormone–releasing hormone (GHRH) (0.4μg/kg body weight [BW]) using 18 heifers with GH genotypes AA, BB, and CC (n=6 for each group). The genotype AA heifers showed the greatest BW among genotypes (P < 0.05). Genotype AC, BC, and CC heifers showed greater GH concentrations than genotype AA, AB, or BB heifers, in which genotype CC heifers had the highest concentrations (P < 0.05). However, IGF-1 concentrations did not significantly differ. The genotype AA and BB heifers had a greater GH release at 60min following GHRH injection than did the genotype CC heifers. The area under the curve (AUC; P < 0.07) and incremental area (IA; P < 0.08) of GH responses to the GHRH challenge tended to be the highest in the genotype AA heifers and the lowest in the genotype CC heifers. In conclusion, GH gene polymorphism altered GH, which may have contributed to differences in BW and carcass traits among genotypes. [Copyright &y& Elsevier]

Abstract: In order to improve creep strength of tempered martensitic 9Cr steel at 650°C, alloy design for a dispersion of fine and thermally stable precipitate particles has been investigated for 9Cr–3W–3Co–VNb steel and 9Cr–2W–VNbTi steel. Creep tests were carried out at 650°C for up to about 10000h. By reducing carbon concentration below 0.02%, a dispersion of nano-size MX nitrides of vanadium and niobium along boundaries as well as in the matrix is achieved in 9Cr–3W–3Co–VNb steel with 0.05% nitrogen. This gives rise to excellent creep strength at 650°C, as shown by much higher creep rupture strength than conventional 9Cr steels P92 and T91. Excess addition of nitrogen, 0.07 and 0.1%, promotes the coarsening of MX nitrides and the formation of Z-phase during creep. A dispersion of nano-size TiC carbides is also achieved in 9Cr–2W–VNb steel containing 0.05% Ti by high-temperature normalizing at 1300°C followed by tempering. This effectively decreases minimum creep rate and improves creep life. [Copyright &y& Elsevier]

Abstract: Mucormycosis is a rare fungal infection with a high mortality that affects immunocompromised patients. This is an unusual case of necrosis of the tongue in a patient with pulmonary mucormycosis, diabetes mellitus, and aplastic anaemia. [Copyright &y& Elsevier]

Abstract: The carbon and nitrogen free new alloys which were composed of supersaturated martensitic microstructure with high dislocation density before the creep test have been investigated systematically. These alloys were produced from the new approach which raised creep strength by the utilization of the reverse transformed austenite phase as a matrix and intermetallic compounds such as Laves phase and mu-phase as precipitates during heating before the creep test. It is important that these alloys are independent of any carbides and nitrides as strengthening factors. The high temperature creep test over 700 °C exceeds 50,000 h, and the test is continuous. Creep behavior of the alloys is found to be different from that of the conventional high-Cr ferritic steels. The addition of boron to the alloy pulled the recrystallization temperature up in the high temperature, and it became a creep test in the un-recrystallization condition, and the creep property of high temperature over 700 °C was drastically improved. The minimum creep rates of Fe–Ni alloys at 700 °C are found to be much lower than those of the conventional high Cr ferritic heat resistant steels, which is due to fine dispersion strengthening useful even at 700 °C in these alloys. As a result it became clear that the value for 100,000 h was exceeded at 700 °C and 100 MPa calculated from the Larson-Miller parameter at C = 20. [Copyright &y& Elsevier]

Abstract: Thermal spray of Ni–Cr and Al coatings was attempted on modified 9Cr–1Mo steel, to evaluate their steam oxidation resistance. Atmospheric plasma spray (APS) coatings of 50Ni–50Cr as undercoat and Al topcoat were attempted with the aim that the pores produced by 50Ni–50Cr undercoat can be filled with Al topcoat during the steam oxidation. The steam oxidized samples evinced the Ni and Cr diffusion towards the Al coating structure and changed the topcoat in to the Ni–Al intermetallics. Though the two-layered coating exhibited an excellent performance against the steam oxidation for the base steel substrate till 3000h of test, the top layers of the coating underwent significant internal oxidation. [Copyright &y& Elsevier]

In order to seek inexpensive substituting elements for Pd in an Fe&z.sbnd;Pd based L10 ordered phase, a phenomenological calculation based on the cluster variation method combined with a Lennard-Jones type pair-wise atomic interaction energies has been attempted for a Fe&z.sbnd;Ni binary system. The phase equilibria for FeNi3-disorder and FeNi-disorder are investigated. In particular, a tetragonal distortion is explicitly considered for the FeNi L10 ordered phase. The calculated FeNi3-disorder phase boundary shows good agreements with an experimental result. An FeNi L10 ordered phase which does not appear in a conventional Fe&z.sbnd;Ni binary phase diagram is predicted as a stable phase, implying that Ni is a potential substituting element for Pd in an Fe&z.sbnd;Pd based L10 ordered phase. [Copyright &y& Elsevier]

We proposed an application methodology that combines metabolic profiling with multiple appropriate multivariate analyses and verified it on the industrial scale of the ripening process of Cheddar cheese to make practical use of hydrophilic low-molecular-weight compound profiling using gas chromatography-mass spectrometry to design optimal conditions and quality monitoring of the cheese ripening process. Principal components analysis provided an overview of the effect of sodium chloride content and kind of lactic acid bacteria starter on the metabolic profile in the ripening process of Cheddar cheese and orthogonal partial least squares-discriminant analysis unveiled the difference in characteristic metabolites. When the sodium chloride contents were different (1.6 and 0.2%) but the same lactic acid bacteria starter was used, the 2 cheeses were classified by orthogonal partial least squares-discriminant analysis from their metabolic profiles, but were not given perfect discrimination. Not much difference existed in the metabolic profile between the 2 cheeses. Compounds including lactose, galactose, lactic acid, 4-aminobutyric acid, and phosphate were identified as contents that differed between the 2 cheeses. On the other hand, in the case of the same salt content of 1.6%, but different kinds of lactic acid bacteria starter, an excellent distinctive discrimination model was obtained, which showed that the difference of lactic acid bacteria starter caused an obvious difference in metabolic profiles. Compounds including lactic acid, lactose, urea, 4-aminobutyric acid, galactose, phosphate, proline, isoleucine, glycine, alanine, lysine, leucine, valine, and pyroglutamic acid were identified as contents that differed between the 2 cheeses. Then, a good sensory prediction model for "rich flavor," which was defined as "thick and rich, including umami taste and soy sauce-like flavor," was constructed based on the metabolic profile during ripening using partial least squares regression analysis. The amino acids proline, leucine, valine, isoleucine, pyroglutamic acid, alanine, glutamic acid, glycine, lysine, tyrosine, serine, phenylalanine, methionine, aspartic acid, and ornithine were extracted as ripening process markers. The present study is not limited to Cheddar cheese and can be applied to various maturation-type natural cheeses. This study provides the technical platform for designing optimal conditions and quality monitoring of the cheese ripening process. [ABSTRACT FROM AUTHOR]

Abstract: The phase and metal/oxide interface structure of the nanometer-scale particles in an Al-alloyed high-Cr oxide dispersion strengthened ferritic steel extruded at 1150°C and 1050°C were characterized by high-resolution transmission electron microscopy and diffraction contrast techniques, including weak beam electron microscopy. After extrusion at 1150°C, yttrium–aluminum–hexagonal (YAH, YAlO3) and yttrium–aluminum–perovskite (YAP, YAlO3) oxides (diameter ⩽10nm) constitute ∼55% and 38% of the particles, respectively; ∼78% of the particles (4.5–10nm in diameter), which include 40% YAH oxide and 38% YAP phase with misfit (translational) moiré fringe spacing of 2.15nm and 1.65nm, respectively, are semi-coherent with the matrix. After extrusion at 1050°C, almost all the particles are YAH phase, and ∼86.5% (diameter <4.5nm) are coherent with the matrix. The coherency of the oxides is size dependent. The crystallographic orientation correlations of the oxides and matrix were found. [ABSTRACT FROM AUTHOR]

Abstract: The corrosion resistances of ODS steels with 0–3.5wt% Al and 13.7–17.3wt% Cr, and a 12Cr steel were examined. The experiments were conducted at 550 and 650°C for up to 3000h in stagnant LBE containing 10−6 and 10−8 wt% oxygen for the ODS steels, and at 550°C for up to 5000h in that containing 10−8 wt% oxygen for the 12Cr steel. Protective Al oxide scales were formed on the surfaces of the ODS steels with approximately 3.5wt% Al and 13.7–17.3wt% Cr. Addition of Al is very effective in improving the corrosion resistance of ODS steels. The ODS steel with 16wt% Cr and no Al did not show any corrosion resistance except in LBE with 10−6 wt% oxygen at 550°C. The corrosion resistance may not be improved by solely increasing Cr concentration. [Copyright &y& Elsevier]

Lennard-Jones type pair-wise atomic interaction energies for Fe&z.sbnd;Fe, Fe&z.sbnd;Pd and Pd&z.sbnd;Pd are derived from extrapolated thermodynamic and structural data of pure elements and an ordered compound. In order to estimate the values at zero Kelvin, extrapolation was performed with the aid of thermodynamic database. Also, additional measurement of ordering energy was attempted by Differential Scanning Calorimetry to determine the L10-disorder transition temperature. The resultant pair interactions are combined with the Cluster Variation Method and the concentration dependency of heats of formation at 1565K was calculated. In addition, the phase boundary for L10-disorder was obtained. Fairly good agreements with experimental results are achieved. [Copyright &y& Elsevier]

Hsp70: J-domain protein (JDP) machines, along with the cellular protein degradation systems play a central role in regulating cellular proteostasis. An equally robust surveillance system operates at the plasma membrane too that affects proper sorting, stability as well as the turnover of membrane proteins. Although plausible, a definitive role of the Hsp70: JDP machine in regulating the stability of plasma membrane proteins is not well understood in Saccharomyces cerevisiae. Here we show that a moderate over-expression of Caj1, one of the thirteen JDPs residing in the nucleo-cytosolic compartment of S. cerevisiae reduced the cold sensitivity of tryptophan auxotrophic yeast cells by stabilizing tryptophan permeases, Tat1 and Tat2 in a J-domain dependent manner. Concomitantly, higher Caj1 levels also caused slow growth and increased plasma membrane damage at elevated temperatures possibly due to the stabilization of thermolabile plasma membrane proteins. Finally, we show that although majorly cytosolic, Caj1 also co-localizes with the membrane dye FM4-64 at the cellular periphery suggesting that Caj1 might interact with the plasma membrane. Based on the results presented in this study, we implicate the Hsp70: Caj1 chaperone machine in regulating the stability or turnover of plasma membrane proteins in budding yeast. Unlabelled Image • Caj1 is the first J-domain protein to associate with plasma membrane. • Caj1 overexpression rescues cold sensitivity of Trp1 auxotrophic strains and causes toxicity at elevated temperatures. • Caj1 overexpression stabilizes amino acid permeases possibly by negatively regulating Rsp5-mediated protein degradation. • Caj1 may have both J-domain dependent as well as J-domain independent functions. [ABSTRACT FROM AUTHOR]