Strengthening mechanisms in nanostructured high-purity aluminium deformed to high strain and annealed

Samples of pure aluminium (99.99%) have been produced by accumulative roll-bonding to a large strain followed by a heat treatment, where a two-step annealing process has been used to produce samples with large variations in structural parameters such as boundary spacing, misorientation angle and dislocation density. These parameters have been quantified by a structural analysis applying transmission electron microscopy and electron backscatter diffraction, and the mechanical properties have been determined by tensile testing at room temperature. Strength–structure relationships have been analysed based on the operation of two strengthening mechanisms—grain boundary and dislocation strengthening—and good agreement with experiments has been found for the deformed sample. However, for samples where the density of dislocation sources has been reduced significantly by annealing, an additional strengthening mechanism, so-called dislocation source-limited hardening, may operate as a higher stress is required to activate alternative dislocation sources.     

Isolation and characterization of a rheumatoid arthritis-specific antigen (RA-A47) from a human chondrocytic cell line (HCS-2/8)

Two types of 47 kDa antigen specifically recognized by sera from rheumatoid arthritis (RA) patients were isolated from the membrane fraction of a human chondrosarcoma-derived chondrocytic cell line (HCS-2/8) by a 2-step procedure: preparative SDS-PAGE and reverse-phase HPLC. An N-terminal amino acid sequence in one of the 47 kDa antigens, named RA-A47, had 81% homology to that deduced from the DNA sequence of the colligin gene which is reported as human hsp47 gene, and 100% homology to that deduced from the DNA sequence of colligin-2 gene, a homologue of colligin. The RA-A47 cross-reacted with a monoclonal antibody raised against chick heat shock protein (Hsp) 47 and bound to gelatin. The expression of the ra-a47 gene was enhanced by heat shock treatment and TGF-beta stimulation. These findings suggest that RA-A47 is a Hsp47-like protein, presumably the product of the colligin-2 gene, and that a collagen-specific molecular chaperone(s) such as Hsp47 and/or RA-A47 is involved in cartilage destruction in RA.     

Purification and characterization of a novel sennoside-hydrolyzing beta-glucosidase from Bifidobacterium sp. strain SEN, a human intestinal anaerobe

A novel beta-glucosidase, which is inducible and capable of catalyzing the hydrolysis of sennosides, was purified from Bifidobacterium sp. strain SEN with Triton X-100 solubilization and DEAE-cellulose column chromatography, by which hydrolytic activities toward sennoside B, 4-methylumbelliferyl beta-glucoside (MUG), and p-nitrophenyl beta-glucoside (pNPG) were obtained together in the same eluted fractions. The activity was stable against detergents such as sodium dodecyl sulfate (SDS) and Triton X-100, but was denatured by SDS and beta-mercaptoethanal when heated. The final preparation was shown to be nearly homogeneous on SDS-polyacrylamide gel electrophoresis (PAGE) either after the enzyme was denatured or when it was not denatured. In the non-denaturing SDS-PAGE, a single protein band hydrolyzed MUG on the gel. In the denaturing SDS-PAGE, the subunit mass of the enzyme was estimated to be 110 kDa. The enzyme was optimally active at pH 6.0 for hydrolysis of sennoside B and MUG. Km values for sennoside B and MUG are 0.94 and 0.53 mM, respectively. The enzyme also catalyzed the hydrolysis of pNPG, amygdalin, geniposide and salicin. It was less active against methyl beta-glucoside and incapable of hydrolyzing cellobiose. The beta-glucosidase activity was inhibited by deoxynojirimycin and p-chloromercuribenzenesulfonic acid, but was less susceptible to several metals (FeSO4, ZnCl2, and CuSO4), and 5,5'-dithio-bis(2-nitrobenzoic acid).     

Influence of external magnetic field on permanent magnet by EDM

REMORA aims at offering an agile robotic solution for manufacturing tasks done on very large parts (e.g., very long and slender parts found in aeronautic industries). For such tasks, classical machine tools are designed at several tens of meters. Both their construction and operation require huge infrastructure supports. REMORA is a novel lightweight concept and flexible robotic solution that combines the ability of walking and manufacturing. The robot is a mobile manufacturing system which can effectuate operations with good payload capacity and good precisions for large workspace applications. This new concept combines parallel kinematics to ensure high stiffness but low inertia and mobile robotics to operate in very large workspaces. This results in a machining center of new generation: (1) agile manufacturing system for large workspace applications, (2) heavy load and good precisions, (3) 5-axis machining and 5-axis locomotion/clamping, (4) self-reconfigurable for specific tasks (workspace and force), and (5) flexible and multifunctional.     

Amide proton transfer (APT) magnetic resonance imaging of prostate cancer: comparison with Gleason scores

Objective

To evaluate the utility of amide proton transfer (APT) imaging in estimating the Gleason score (GS) of prostate cancer (Pca).

Materials and methods

Sixty-six biopsy-proven cancers were categorized into four groups according to the GS: GS-6 (3 + 3); GS-7 (3 + 4/4 + 3); GS-8 (4 + 4) and GS-9 (4 + 5/5 + 4). APT signal intensities (APT SIs) and apparent diffusion coefficient (ADC) values of each GS group were compared by one-way analysis of variance with Tukey’s HSD post hoc test.

Results

The mean and standard deviation of the APT SIs (%) and ADC values (×10^?3 mm²/s) were as follows: GS-6, 2.48 ± 0.59 and 1.16 ± 0.26; GS-7, 5.17 ± 0.66 and 0.92 ± 0.18; GS-8, 2.56 ± 0.85 and 0.86 ± 0.17; GS-9, 1.96 ± 0.75 and 0.85 ± 0.18, respectively. The APT SI of the GS-7 group was highest, and there were significant differences between the GS-6 and GS-7 groups and the GS-7 and GS-9 groups (p < 0.05). The ADC value of the GS-6 group was significantly higher than each value of the GS-7, GS-8, and GS-9 groups (p < 0.05), but no significant differences were obtained among the GS-7, GS-8, and GS-9 groups.

Conclusion

The mean APT SI in Pca with a GS of 7 was higher than that for the other GS groups.

     

Evaluation of neutron nuclear data on xenon isotopes

Neutron nuclear data of Xe isotopes have been evaluated in the energy region, including the resolved resonance one, from 1 keV to 20 MeV by using the theoretical nuclear reaction models. The phenomenological optical model potential was employed to calculate the total cross section for natural Xe with the coupled-channels method. The cross sections for channels of capture, (n, 2n), (n, p) and (n, α) reactions were calculated and compared with available experimental results including recently measured data. The elastic scattering angular distributions and particle emission spectra were calculated, although there is no experimental information available. Reaction cross sections of evaluated libraries were considered for comparison with the calculated results. The presently calculated cross sections reproduce better the available experimental data.     

1,8-Cineole Ameliorates Steatosis of Pten Liver Specific KO Mice via Akt Inactivation

Hepatocyte-specific Phosphatase and tensin homolog (Pten)-knockout (KO) mice exhibit hepatic lesions analogous to non-alcoholic steatohepatitis (NASH). 1,8-cineole is a monoterpene oxide and it has several biological effects including hepatoprotective effects. In this study we revealed that 1,8-cineole ameliorates NASH of Pten KO mice. Pten KO mice were assigned to a control group without any medication or to a 1,8-cineole group injected with 50 mg/kg i.p. twice per week for eight weeks. At eight weeks, livers from each group were processed to measure triglyceride (TG) content, gene expression analysis, western blot analysis, and histological examination including Oil red O staining. 1,8-cineole ameliorated hepatic steatosis in Pten KO mice, revealed by TG content and Oil red O staining. Moreover, 1,8-cineole downregulated collagen 1a1 expression and improved liver fibrosis. Thus, 1,8-cineole has potential as a candidate to treat NASH by inactivating the Akt/PI3-kinase pathway.