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We have presented herein the results of microstructure, surface magnetic domains (SMDs), and giant magneto-impedance (GMI) effect of melt-extracted Co68.15Fe4.35Si12.25B11.25Nb2Cu2 amorphous wires for the first time employed by using a cryogenic Joule annealing (CJA) technique with large DC current amplitude. Compared with the conventional JA method, experimental results indicate that the maximum GMI ratio [ΔZ/Z0]max achieves up to 425% at 8.1MHz with monotonic increase of the axial magnetic field Hex up to 6.5 Oe for 300mA (equal to around 1.06×106A/dm–2) CJA-ed wire, which is about 75% larger than the [ΔZ/Z0]max for the 100mA (nearly 3.53×105A/dm–2) JA-ed microwires. The remarkable features of large and linearly sensitive response field (2.5~6.5 Oe) and the sensitivity of 99.4%/Oe with higher GMI ratio simultaneously make the CJA tailored melt-extracted microwires promising candidate materials for miniaturized GMI sensors. Another interesting result of GMI profiles of 200mA (appropriately equal to 7.07×105A/dm–2) CJA-ed wire show a linear response to Hex (ranging from 10 to 80 Oe or more), this behavior of GMI curves can be explored to fabricate bi-sensor. Large response field proves to originate from the intensive coupling between the radial stress field and the circumferential magnetic field during CJA process. The effect of outer-shell microstructure and complex SMD for 300mA CJA-ed microwire is attributed to the fact that liquid nitrogen hinders the evolution of circumferential domain structure to some extent and protects the amorphous structure in the shell region. [ABSTRACT FROM AUTHOR]

Rice is one of the most important cereal crops and is susceptible to salinity stress. To enhance biotic and abiotic stress tolerance in crops, the application of silicon (Si) during seedling culture and seed priming are two effective approaches. However, whether seed priming with silicon can enhance salinity stress tolerance in rice seedlings, and what the optimal concentration of Si treatment is largely unclear. In this study, rice seeds were pretreated with sodium silicate, and the hydroponically grown rice seedlings were exposed to sodium chloride. Our results show that seed soaking with Si can significantly improve the growth of rice seedlings under salinity-stress, as evidenced by enhanced fresh weight, dry weight, leaf relative water content, photosynthetic pigment level, soluble protein content, as well as the activities of POD and SOD enzymes. Moreover, Si-pretreated seeds showed accelerated seed germination, increased seedling height and reduced root length. Furthermore, qRT-PCR analysis showed that seed soaking with Si induced the transcription of genes encoding Na+/H+ exchangers and H+-pyrophosphatase. Our results imply that seed priming with Si enhances seedling tolerance to salinity stress without negative effect on growth and it can be used as an effective strategy. [ABSTRACT FROM AUTHOR]

How to evaluate the fuel gas operation (FGO) of various working groups (WGs) and working shifts (WSs) in reheating furnace is still ambiguous problem. In this paper, a novelty time-series FGO evaluation model was proposed. The strategy mainly included: Firstly, the fuel gas per ton steel (FGTS) was calculated in certain time interval; Secondly, the FGTS time-series data set was formulated in statistical period; Thirdly, the FGTS time-series data set was divided according to working schedule; Lastly, the FGO evaluation model was established. Case study showed that: i) The fuel gas operation evaluation results of various WGs in different WSs were accorded with normal distribution; ii) For various WGs, A WG performed best, followed by C WG and D WG. The performance of B WG was the worst due to its violent fluctuation of fuel gas operation evaluation results in three WSs; iii) For different WSs, the day WS and swing WS performed well, whereas the performance of night WS was unsatisfactory. Discussion results showed that the improvement of working skills, working responsibility and working passion, which were effective measure to achieve energy saving in terms of operation, should be enhanced through skills training and the reward and punishment system. Generally, this novelty time-series FGO evaluation method could also be applied to other industrial equipment. [ABSTRACT FROM AUTHOR]

Silicon (Si) enhances plant resistance to various forms of stress. However, the availability of Si as a plant nutrient is frequently limited. Bryophytes are able to grow on the surface of rocks and buildings with high Si accumulation. Therefore, bryophyte rhizoids might harbor microorganisms capable of solubilizing Si. In this study, silicate solubilizing bacteria (SSB) were isolated from the rhizoids of the bryophyte Hypnum plumaeforme L. to examine their effects on Si weathering and growth of maize (Zea mays L.). Molecular phylogeny and 16S rRNA gene sequence analysis demonstrated that the dominant bacterial strain B1-5 was a member of the Kosakonia genus. The concentrations of soluble Si released from the feldspar and quartz powder in liquid media with strain B1-5 inoculation were higher than those of the control. B1-5 inoculation in pot soil significantly increased the water-extractable Si content in soil, improved Si uptake and accumulation in maize plants, and promoted seedling growth. These results not only prove the existence of SSB in bryophyte rhizoids, but also demonstrate a new approach to searching for effective biological Si fertilizers. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the anti-apoptotic effect of perindopril on myocardial cells in mice with acute myocardial infarction (AMI). MATERIALS AND METHODS: A total of 48 mice were randomly divided into 4 groups before intervention, namely sham operation group (Sham group, n=12), AMI group (n=12), 1.5 mg/ kg perindopril treatment group (Perindopril group, n=12), and 1.5 mg/kg perindopril treatment and Toll-like receptor-4 (TLR4) knockout group (TLR4-/-Perindopril group, n=12). Mice in the control group and AMI group were gavaged with normal saline, and those in the Perindopril group and TLR4-/-Perindopril group were gavaged with perindopril for 7 d. On the 4th day after drug administration, mice in the AMI group, Perindopril group and TLR4-/-Perindopril group were subjected to the ligation of the anterior descending coronary artery to induce AMI, and those in the Sham group underwent the same operation, but had a loose knot at the anterior descending coronary artery. At 24 h after the above operation, color echocardiography was performed on mice to observe changes in cardiac function. Then, the mice were sacrificed. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick end labeling (TUNEL) assay was carried out to determine myocardial apoptosis. Immunohistochemistry and Western blotting technique were employed to detect the protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), TLR4 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p50 in infarction zones. The messenger ribonucleic acid (mRNA) expression levels of TLR4 and NF-κB p50 in infarction zones were measured via Reverse Transcription-Polymerase Chain Reaction (RT-PCR). RESULTS: Perindopril could significantly reduce the number of apoptotic myocardial cells after AMI. Mouse echocardiography showed that ejection fraction (EF), left ventricular fractional shortening (FS), left ventricular end-systolic diameter (LVESD) and left ventricular end-diastolic diameter (LVEDD) of AMI mice in the Perindopril groups were markedly superior to those in the AMI group. AMI mice in the Perindopril group had decreased expression levels of Bax protein and TLR4 and NF-κB p50 mRNA and protein, as well as the Bax/Bcl-2 ratio. Knockout of TLR4 attenuated the effect of perindopril in alleviating myocardial apoptosis after AMI. CONCLUSIONS: Perindopril inhibits myocardial apoptosis in mice with AMI through the TLR4/NF-κB pathway. [ABSTRACT FROM AUTHOR]

The effect of Zn addition on the magnetic properties and microstructure of bulk hot-deformed (NdDy)11.5Fe82.5-xNbxB6 (x = 0-2) alloys has been investigated. The remanence (Br) and coercivity (Hci) can be enhanced substantially by the addition of Nb and can be further improved by the combined addition of Nb and Zn. The addition of Nb increases the volume fraction of intergranular phase and promotes more Zn to diffuse into the grain boundary. This grain boundary with changed properties may benefit the c-axis texture formation during hot-deformation. Additionally, the coercivity of alloys with both Nb and Zn increased up to 22% with increasing deformation ratio, which may be due to the further diffusion of Zn into the grain boundary and the enhancement of magnetic decoupling effect between Nd2Fe14B grains. [ABSTRACT FROM AUTHOR]

Passive iron-oxide nanocrystals are grown on Fe(100) and Fe(110) facets of single-crystal Fe whiskers. Transmission electron microscopy and electron diffraction characterize the oxide spinel structure and their epitaxial growth on Fe whiskers. Iron-oxide nanocrystals grown on Fe(100) facets have sizes close to that of the single magnetic domain Fe3O4 particles, which is supported by our preliminary magnetic force microscopy measurement at room temperature. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]