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Lesion mimic mutants (LMMs) are plants that spontaneously form lesions without pathogen infection or external stimulus and exhibit resistance to pathogens. Here, a rice LMM was created by ethyl methane sulfonate mutagenesis, named as hpil (hydrogen peroxide induced lesion). Diaminobenzidine and trypan blue staining showed that large amounts of H2O2 were produced and cell death was occurred at and around the parts of lesion mimic in the rice leaves. The phenotype of hpil is controlled by a single recessive gene, localized at a 2 Mb interval on chromosome 2. The data suggested that hpil is a novel LMM with enhanced bacterial and fungal disease resistance, and multiple pathogenesis-related proteins (PRs) were up-regulated. The proteomes of leaves at three positions (different degrees of lesion mimic severity) were characterized in hpil compared with its wild type plant. Differentially expressed proteins were detected by two dimensional difference gel electrophoresis and 274 proteins were identified by MALDI TOF/TOF™. These proteins were related to metabolic process, cellular process and response to stimulus, with mostly down-regulated in hpil leaves. Many of these proteins were related to the Calvin cycle, photosynthetic electron transport chain, glycolysis/gluconeogenesis and phosphonates pathways. Some resistance-related proteins including 14-3-3 proteins, OsPR10 and antioxidases such as peroxidase, superoxide dismutase and ascorbate peroxidase were up-regulated in leaves with lesion mimic. These results provide the foundation for cloning of the target gene and shed light on the mechanism involved in autoimmunity of rice.

OsPR10a is one of the well known pathogenesis-related genes in rice, and is induced by multiple plant hormones and pathogens. However, the underlying transcriptional regulation mechanisms in response to different signals and their crosstalks are still largely unknown. In order to find new players participated in the activation of OsPR10a, we systematically analyzed the basal expression patterns as well as the expression responses of a 2.5 kb OsPR10a promoter in rice transgenic plants after phytohormone and pathogen stimulations. In agreement with the native gene expression, the OsPR10a promoter can drive glucuronidase (GUS) gene expressing in spots of leaf cells, leaf trichomes, lemmas and paleae, germinating embryos, calli and root tips. The leaf expression of OsPR10a::GUS was dramatically increased upon jasmonic acid (JA) and cytokinin (CK) treatments, or challenges of the pathogen Magnaporthe grisea and Xanthomonas oryzae pv. oryzae. Thus, the OsPR10a promoter reported here can faithfully reflect its native gene expression. The effects of several JA and CK responsive OsWRKY genes on the regulation of OsPR10a promoter were then inspected by luciferase transient expression assay, and the JA inducible OsWRKY10 transcription factor was found as a new positive regulator of OsPR10a. However, the key transcription factors of JA and CK signaling pathways, OsMYC2 and B-type response regulators, were not responsible for the activation of OsPR10a promoter. Our findings provided new insights into the regulation of OsPR10a expression during plant-hormone/pathogen interactions, and the OsPR10a reporter system can be useful to unravel novel regulators from both pathogen and host.

ObjectiveTo explore the biological role of miR-206 in inhibiting the proliferation and invasion of estrogen-induced ER-α36 positive gastric cancer cells and its related mechanisms.MethodsMTT and tranwell assays were used to detect the proliferation and invasion of BGC-823 cells under different concentrations and time of ER stimulation. RT-PCR was used to detect the effect of ER stimulation on the content of miR-206 in gastric cancer cells. miR-206 mimics were transfected into BGC-823 cells to detect cell proliferation and invasion; luciferase reporter assay was used to determine whether miR-206 targets the 3’-untranslated region of the CDK14-encoding gene (3’ -UTR).ResultsWe confirmed that estrogen promoted the proliferation and invasion of BGC-823 cells; As the concentration of estrogen increases, the level of miR206 in the cell gradually rises.Overexpression of miR-206 significantly decreased the estrogen-induced BGC-823 cells. Proliferative and invasive ability; miR-206 inhibits the expression of CDK14 by directly binding to the 3’-UTR of CDK14 mRNA, thereby inhibiting the proliferation and invasion of gastric cancer cells.ConclusionsOur results suggest that miR-206 inhibits estrogen-induced proliferation and invasion of ER-α36-positive gastric cancer cells by inhibiting CDK14 and may be a promising therapeutic option for anticancer therapy.

Gas-sensing performance of graphene-based material has been investigated widely in recent years. Polyaniline (PANI) has been reported as an effective method to improve ammonia gas sensors’ response. A gas sensor based on a composite of rGO film and protic acid doped polyaniline (PA-PANI) with GO doping is reported in this work. GO mainly provides NH3 adsorption sites, and PA-PANI is responsible for charge transfer during the gas-sensing response process. The experimental results indicate that the NH3 gas response of rGO is enhanced significantly by decorating with PA-PANI. Moreover, a small amount of GO mixed with PA-PANI is beneficial to increase the gas response, which showed an improvement of 262.5% at 25 ppm comparing to no GO mixing in PA-PANI.

It is a daunting challenge to measure the concentration of each component in natural gas, because different components in mixed gas have cross-sensitivity for a single sensor. We have developed a mixed gas identification device based on a neural network algorithm, which can be used for the online detection of natural gas. The neural network technology is used to eliminate the cross-sensitivity of mixed gases to each sensor, in order to accurately recognize the concentrations of methane, ethane and propane, respectively. The neural network algorithm is implemented by a Field-Programmable Gate Array (FPGA) in the device, which has the advantages of small size and fast response. FPGAs take advantage of parallel computing and greatly speed up the computational process of neural networks. Within the range of 0&ndash, 100% of methane, the test error for methane and heavy alkanes such as ethane and propane is less than 0.5%, and the response speed is several seconds.

In this thesis, mechanical properties of 0.3Ni and 3Ni low-temperature steel materials at low temperature were measured via tensile test and impact toughness test at low temperature, and applicable temperatures at low temperature of two new materials for iron tower were researched. The result shows that the strength of 0.3Ni steel is much higher than that of 3Ni steel, while the plasticity of 3Ni steel is better than that of 0.3Ni steel; the ductile-brittle transition temperature of steel material for power transmission iron tower is defined with impact energy 21J, then the ductile-brittle transition temperature of 0.3Ni low-temperature steel is about -70°C, and that of 3Ni low-temperature steel is about -120°C. With regard to steel using for power transmission iron tower under extremely low temperature conditions in our country, it is suggested that 0.3Ni low-temperature steel should be adopted in cold areas with temperature lower than -60°C.

The effect of different infiltration aluminum temperature and cooling method of heat treatment process on mechanical properties of aluminized steel were investigated, The mechanical properties results show that, mechanical performance change condition of the raw material is mainly affected by the heat treatment processing after the common steel Q345 is heat treated. It is found reduction influence of mechanical performance on the raw material is very great if the aluminizing process is different during actual application process of the power steel. When the aluminizing temperature is reduced to 715-735 °C, mechanical properties of the raw materials can maintain by using air cooling heat-treatment.

A comparative study of wear characteristics between aluminized steel, galvanized steel and Q345 was conducted, using scanning electron microscopy (SEM) and energy dispersive spectrometer. Wear weight loss test demonstrated that weight loss of aluminized steel was significantly lower than that of galvanized steel, and the weight loss increased slowly with the loading force. When the loading force increased from 3 N to 19 N, weight loss value was enhanced from 0.87 mg to 2.15 mg, and the maximum value is only 19.8% of Q345 steel, 28.1% of galvanized steel. Phase analysis of the wear of aluminized steel, galvanized steel and Q345 showed that wear-resistant medium of aluminized steel was Fe-Al-O compounds, and wear-resistant medium of galvanized steel was Fe-Zn alloy oxide. Wear mechanism analysis show that the Q345 wear mechanism is adhesive wear, and aluminized steel was abrasive wear.

Being a proven photocatalyst, nano-anatase is capable of undergoing electron transfer reactions under light. In previous studies, we had proven that nano-anatase improved photosynthesis and greatly promoted spinach growth. However, the molecular mechanisms of carbon reaction promoted by nano-anatase are still not clearly understood. In the present paper, reverse transcription polymerase chain reaction and Northern blotting were carried out, and the results showed that the expression of ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) small subunit (rbcS) and Rubisco large subunit (rbcL) messenger RNA (mRNA) in the nano-anatase-treated spinach were obviously promoted, respectively, while the effects of bulk TiO2 were not so significant. Accordingly, the protein expression of Rubisco from the nano-anatase-treated spinach was increased by 40% compared with control. Further analysis indicated that the activity of Rubisco in the nano-anatase-treated spinach was significantly higher than the control, by up to 2.33 times, and bulk TiO2 treatment had no such significant effects. Together, one of the molecular mechanisms of carbon reaction promoted by nano-anatase is that the nano-anatase treatment results in the enhancement of Rubisco mRNA amounts, the protein levels, and activity of Rubisco, thereby leading to the improvement of Rubisco carboxylation and the high rate of photosynthetic carbon reaction.

We report on the first dark-matter (DM) search results from PandaX-I, a low threshold dual-phase xenon experiment operating at the China Jinping Underground Laboratory. In the 37-kg liquid xenon target with 17.4 live-days of exposure, no DM particle candidate event was found. This result sets a stringent limit for low-mass DM particles and disfavors the interpretation of previously-reported positive experimental results. The minimum upper limit, $3.7\times10^{-44}$\,cm$^2$, for the spin-independent isoscalar DM-particle-nucleon scattering cross section is obtained at a DM-particle mass of 49\,GeV/c$^2$ at 90\% confidence level., Comment: 7 pages, 6 figures, final version as appeared in the journal publication

The possible mediatory role of salicylic acid (SA) in protecting plants from cadmium (Cd) toxicity was investigated. Increasing Cd concentrations caused a decrease in shoot and root biomass, chlorophyll (a, b) and carotenoids content, and photosynthetic rate in plants. Pretreatment with 500 µM SA did not change the plant growth, Cd accumulation, and water relation in Cd-stressed plants. Moreover, it can aggravate Cdinduced decline of photosynthetic rate in plants exposed to 25 mg Cd kg-1 soil, by reducing the stomatal conductance and pigment contents. These results suggest that exogenous SA may not improve the tolerance of the castor bean plants to the Cd toxicity under soil conditions.