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There is little knowledge about whether biochar amendment can reduce soil salinity, though increasing data have shown that biochar amendment can improve soil fertility and crop production. In this study, we hypothesized that biochar amendment could promote salt leaching, and the effect might depend on biochar properties. The aims were to evaluate the impacts of three biochars on promoting salt washing and then find possible biochars as saline soil conditioner. Three biochars derived from rice (Oryza sativa L.) straw (RSB), sunflower (Helianthus annuus) straw (SSB), and cow manure (CMB) through a slow pyrolysis process were respectively added at a rate of 5% (w/w) into 0 to 35 cm (0 to 13.8 in) soil depth of a sulfate (SO42−) saline soil column. After washing with deionized water, the eluent was collected from each column and then measured for electrical conductivity (EC) and major salt ions. At the end of washing, the major salt ions were determined in each soil layer. Results showed that the biochar-amended columns discharged efflux 24 to 40 days earlier than that of the control without biochar (CK). Biochar addition saved 56 to 62 days for the EC values of the efflux to be reduced to 5 dS m−1. Among the three biochars, SSB led to much lower contents of the most detrimental ions of both sodium (Na+) and bicarbonate (HCO3−) in the soil at the end of experiment, showing that SSB may be a highly potential amendment of saline soils in the Hetao region in China. Further work is required for investigating and confirming the effect of biochar amendment on different saline soils with different textures, salinities, and alkalinities in both lab and field, together with local irrigation water, and then quantifying water saving and crop production through biochar amendment in agriculture.

The Co-base alloy laser cladding layer was coated on the 2738 mold steel surface by using the TJ-HL-5000 transverse-flow CO2 continuous laser. The morphology and hardness were investigated by metallography microscope, scanning electron microscopy (SEM), X-ray diffraction (XRD) and microhardness tester. The metallography microscope and SEM investigations show that from interface to surface along the cross section direction, the cladding layers consist of plane crystal layer, columnar crystal layer, dendrites layer and surface cellular crystal layer, respectively. XRD results indicate that the cladding layer is made of γ-Co, Cr23C6, MoC, FeCr and Co3Mo2Si phases. The micro-hardness of the laser cladding coating was about 900-1100HV1, 3 times or more of the steel substrate. And the mechanisms of microstructure formation and strengthening are investigated.

The Co-based alloy coatings were successfully fabricated on H13 steel by Nd:YAG and CO2laser. The microstructure and properties of the laser cladded coatings were compared and analyzed by SEM, EDS, XRD and microhardness tester. The results show that the excellent metallurgical bonding has formed at the interface between substrate and laser cladded coatings. Cellular crystal at the bonding zone, cellular dendrite at the central zone and reticular equiaxed crystal near top surface were observed in Nd:YAG laser cladded coating, while the typically hypoeutectic character was found in CO2laser cladded coating. Phase constituents of both coatings are mainly composed of Cr23C6, Co3Mo2Si, MoC, FeCr and γ-Co. The microhardness of H13 steel is greatly improved by laser cladding, however the microhardness of the CO2laser cladded coating is even higher than the Nd:YAG laser cladded coating.

The capacity of Candida albicans to invade and damage oral epithelial cells is critical for its ability to establish and maintain symptomatic oropharyngeal infection. Although oral epithelial cells are reported dead after 18 h of candidal infection, activation of specific epithelial cell-death pathways in response to C. albicans infection has not yet been demonstrated. Considering the key role of oral epithelial cell damage in the pathogenesis of oropharyngeal candidiasis, the aim of this study was to characterize this event during infection. Using an oral epithelial-C. albicans co-culture system, we examined the ability of C. albicans to induce classic necrotic, pyroptotic and apoptotic cellular alterations in oral epithelial cells such as osmotic lysis, exposure of phosphatidylserine on the epithelial cell plasma membrane and internucleosomal DNA fragmentation. It was found that the ability of C. albicans to kill oral epithelial cells depends on its capacity to physically interact with and invade these cells. Caspase-dependent apoptotic pathways were activated early during C. albicans infection and contributed to C. albicans-induced oral epithelial cell death. Earlier apoptotic events were followed by necrotic death of infected oral epithelial cells. Hence, C. albicans stimulates oral epithelial signaling pathways that promote early apoptotic cell death through the activation of cellular caspases, followed by late necrosis.

This paper analyzes the leakage reasons of mechanical shaft seals used usually in water-dripper or industry pumps, a basic flowchart of leakage analysis is proposed. Based on the above contents, an intelligence recognition algorithm for judging seal fault feature is given, so an intelligent fault judgment system based on the knowledge may be constructed.

Endoplasmic reticulum stress-mediated apoptosis plays an important role in the destruction of pancreatic beta-cell, and contributes to the development of type 1 diabetes. The chaperone molecule, glucose regulated proteins 78 (GRP78), is required to maintain ER function during toxic insults. In this study, we investigated the effect of GRP78 on the beta-cell apoptosis. We first measured GRP78 protein expression in different phase of streptozotocin-affected beta-cell by immunoblotting analysis. An insulinoma cell line, NIT-1, transfected with GRP78 was established, named NIT-GRP78, and used to study apoptosis, which was induced by streptozotocin or inflammatory cytokines. Apoptosis of NIT-1 or NIT-GRP78 cells was detected by flow cytometry, the transcription of C/EBP homologous protein (CHOP) was monitored by real-time PCR, the concentration of nitric oxide and the activity of superoxide dismutase were measured by colorimetric method. We found that, in comparison to NIT-1 cells, NIT-GRP78 cells responded to the streptozotocin or cytokines treatments with decreased concentration of nitric oxide, but increased activity of superoxide dismutase. In addition, the level of CHOP was also decreased in the NIT-GRP78 cells, which may mediate the resistance of the GRP78 overexpressed NIT-1 cells from apoptosis. Finally, we found that NIT-GRP78 cells were also more resistant than NIT-1 cells to cytotoxic T lymphocyte (CTL) specific killing detected by flow cytometry through target cells expressing green fluorescent protein cultured with effector cells and finally stained with propidium iodide. The data suggest that modulating GRP78 expression could be useful in preventing pancreatic beta-cell from the immunological destruction in type 1 diabetes individuals.

The effects of Co and Zn doping on the magnetization of Bi2212 have been studied. It was found that the critical current density J c and the irreversibility field H irr behaved quite differently between them. For Co-doped Bi2212, the crossover temperatures in both H irr ( T ) and J c well correspond to each other, suggesting collective pinning of 2D vortices. Co doping tends to shift H irr ( T ) downward in the H – T phase diagram, and systematically suppresses J c . For Zn doping, however, such correlation concerning crossover temperatures was not found. The behavior of H irr cannot be explained by existing models. J c for all Zn-doped samples was much larger than that of pure Bi2212, and gradually decreased with the increase of Zn content, indicating that smaller amount of Zn is useful to enhance H irr ( T ) and J c without severe reduction of T c . The contrastive results with Co and Zn doping are briefly discussed.

It is demonstrated that an IrSi/Si Schottky barrier can be formed by electron beam evaporation and annealing of Ir films on