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The influences of Ca and Ce/La microalloying on the microstructure evolution and bio-corrosion resistances of extruded Mg-Zn alloys have been systematically investigated in the current study. Compared with single Ca or Ce/La addition, the Ca-Ce/La cooperative microalloying results in an outstanding grain refinement, because the fine secondary phase particles effectively hinder the recrystallized grain growth. The coarse Ca2Mg6Zn3 phases promote the formation of Ca3(PO4)2 or hydroxyapatite particles during the immersion process and accelerate the dissolution of the corrosion product film, which destroys its integrity and results in the deterioration of anti-corrosive performance. The Ce/La elements can be dispersed within the conventional Mg7Zn3 phases, which reduce the internal galvanic corrosion between Mg matrix and the secondary phases, leading to an obvious improvement of corrosion resistance. Therefore, the Ca-Ce/La cooperative microalloying achieves a homogenous fine-grained microstructure and improves the protective ability of surface film, which will pave a new avenue for the design of biomedical Mg alloys in the coming future.

The evolution of the texture and microstructure of TiB-TC25G composites, heat-treated in the high α+β phase field, have been studied with different cooling rates. The present study found that the size of α colonies and the thickness of individual secondary α laths increased with decreasing cooling rates. Slow cooling induces the formation of equiaxed secondary α grains in the β matrix of TiB-TC25G composites. Attributed to the TiB, the intensity of α texture in TiB-TC25G composites decreased with decreasing cooling rate, which is inconsistent with the results of variant selection during the β→α phase transformation in traditional titanium alloys. The misorientation analysis suggested that some of the equiaxed secondary α grains do not follow the Burgers orientation relationship (BOR) with the parent β grain. In this study, the role of TiB in influencing variant selection and the morphology of the secondary α phase with different cooling rates were analyzed.

The objective of this study was to determine how bovine mammary protein profiles vary during lactation and the dry period. Three lactating and 3 nonlactating cows were selected for mammary gland tissue sampling. Compared with the mammary proteins in nonlactating cows, a total of 60 differentially expressed proteins (DEP, including 57 upregulated and 3 downregulated) were identified in lactating cows using 2-dimensional difference gel electrophoresis combined with mass spectrometry. These DEP included enzymes and proteins associated with various macromolecular metabolic processes, and appeared to promote the increased metabolic activity associated with milk synthesis and secretion. The increased DEP were primarily related to initiation, maintenance, and involution of lactation, and included proteins involved in glycolysis/gluconeogenesis, the tricarboxylic acid cycle, the pentose phosphate pathway, oxidative phosphorylation, aminoacyl-transfer RNA biosynthesis, and fatty acid biosynthesis. Identified DEP were further validated by real-time, reverse-transcription PCR and Western blot. Five new DEP associated with lactation were uniquely identified. This work provided some protein-associated insights to facilitate further investigation of the mechanisms underlying lactation in dairy cows.

We study D 0 D ¯ 0 pairs produced in e + e − collisions at s = 3.773 GeV using a data sample of 2.92 fb−1 collected with the BESIII detector. We measured the asymmetry A K π CP of the branching fractions of D → K − π + in CP-odd and CP-even eigenstates to be ( 12.7 ± 1.3 ± 0.7 ) × 10 − 2 . A K π CP can be used to extract the strong phase difference δ K π between the doubly Cabibbo-suppressed process D ¯ 0 → K − π + and the Cabibbo-favored process D 0 → K − π + . Using world-average values of external parameters, we obtain cos δ K π = 1.02 ± 0.11 ± 0.06 ± 0.01 . Here, the first and second uncertainties are statistical and systematic, respectively, while the third uncertainty arises from the external parameters. This is the most precise measurement of δ K π to date.

The helium-cooled ceramic breeder (HCCB) test blanket module (TBM) is the primary option of the Chinese TBM program. Current progress on the design and R&D for Chinese helium-cooled ceramic breeder TBM (CN HCCB TBM) in China is presented. The main updated design and related R&D of CN HCCB TBM are introduced briefly. The mock-up fabrication and component tests for Chinese test blanket module are being carried out. Recent status of the components and fabrication technology development is also reported. The neutron multiplier Be pebbles, tritium breeder Li4SiO4 pebbles, and structure material CFL-1 are being prepared in the laboratory scale. The fabrication of 1/3 sized mock-up and construction of a He test loop are being carried out. The key technology development is proceeding to the large scale mock-up fabrication and demonstration tests toward on ITER testing.

We study the decays of the J / ψ and ψ ′ mesons to π + π − π 0 using data samples at both resonances collected with the BES III detector in 2009. We measure the corresponding branching fractions with unprecedented precision and provide mass spectra and Dalitz plots. The branching fraction for J / ψ → π + π − π 0 is determined to be ( 2.137 ± 0.004 ( stat. ) − 0.056 + 0.058 ( syst. ) − 0.026 + 0.027 ( norm. ) ) × 10 − 2 , and the branching fraction for ψ ′ → π + π − π 0 is measured as ( 2.14 ± 0.03 ( stat. ) − 0.07 + 0.08 ( syst. ) − 0.08 + 0.09 ( norm. ) ) × 10 − 4 . The J / ψ decay is found to be dominated by an intermediate ρ ( 770 ) state, whereas the ψ ′ decay is dominated by di-pion masses around 2.2 GeV/ c 2 , leading to strikingly different Dalitz distributions.

The presence of crack-like defects can cause an uneven distribution of the electric current density in a cracked conductor. To investigate the perturbation of the magnetic field resulting from the disturbed electric current, computational modeling of the magnetostatics is attempted on an infinite conductive plate, which contains an elliptic hole and is subjected to uniform current flow at infinity. Both 2-D and 3-D analyses are considered in this study. The 2-D analysis requires certain crucial assumptions and the governing Maxwell's equations are solved analytically in elliptic coordinates. The 3-D numerical computation is based on superposition of the elementary solution, whose derivation utilizes the Biot-Savart law. To improve the efficiency of the 3-D calculation, an adaptive mesh refinement algorithm is implemented in the numerical discretization. Finally, through a comparative study, the validity of the introduced simplifications in the 2-D analysis is benchmarked with the 3-D computational results. The present study shows that the 2-D solution predicts the upper bound for the out-of-plane component of the magnetic field perturbed by the elliptical hole, whose semi-major axis does not exceed ten times the thickness of the plate.

Isoflavones are a group of phytoestrogens found in many plants, and daidzein is one of their major metabolites. Previous studies have shown that daidzein affects growth of rumen bacteria and intestinal microflora. This study investigated effects of daidzein on rumen microbial fermentation. Substrate containing ground Chinese wildrye hay (7 g/L), corn grain powder (2.1 g/L) and soybean meal (0.9 g/L) was fermented in vitro by mixed rumen microorganisms and substrate containing rice straw (8 g/L) by rumen anaerobic fungi from four rumen fistulated male goats. Results with mixed rumen microorganisms showed that daidzein treatment had no effect on the total VFA, but maximized propionate at about 10 mg/L (quadratic P

The tensile behavior of Cu-Cr-Zr alloy was investigated at different temperatures. The material investigated was heat treated to the following condition: solutionizing 980 °C -40 min then water quenching, aging 460 °C -4 h. The test temperature was ranged from room temperature to 600 °C at intervals of 100 °C. Curves describing the tensile properties were obtained. The Vickers hardness, microstructure and fracture surface of the tested alloys were also studied. The results reveal that the tensile strength of Cu-Cr-Zr alloys decreases with the increase of temperatures. Additionally, due to fully recrystallization, a combination of a high tensile strength with a fairly good plasticity c an be achieved at 200° C. The suitable working temperature of Cu-Cr-Zr alloy ranges form room temperature to 300° C.The results also indicate that the mechanism of Cu-Cr-Zr alloy fracture is the nucleation, growth, extension and join of microvoid caused by second phase particle.

We independently assessed the frequency, severity and determinants of neurological deficits after endovascular embolization with NBCA of brain arteriovenous malformations (BAVMs) to have a better basis for making treatment decisions. All the charts of 469 BAVMs patients who underwent embolization with NBCA were reviewed. We analyzed the complications and their relation to angiographic features. The 469 patients were treated with 1108 endovascular procedures. Each met one to eight times, average 2.3 times. Eleven patients showed treatment-related complications, including four haemorrhagic and seven ischemic complications. Of these 11 cases, two died, two had persistent disabling deficits, and another seven suffered transient neurological deficits. Our finding suggests a low rate of disabling treatment complications for embolization of brain AVMs with NBCA in this center. The management of AVM patients who have high risk of embolization therapy should be treated by special strategy.