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Water stress is the most important adverse factor limiting rice production. Too much water leads to flood and too little leads to drought. Floods and droughts can severely damage crop at different times of the rice life cycle. So the research on submergence tolerance and drought resistance of rice is particularly urgent. In this study, we reported that OsEBP89 (Oryza sativa Ethylene-responsive element binding protein, clone 89), a member of the AP2/ERF subfamily, is involved in a novel signal transduction associated with the tolerance to drought and submergence stress. OsEBP89 was found to be strongly inhibited by drought stress and promoted by submergence. The OsEBP89 protein was located at the nucleus in the rice protoplast. Loss of OsEBP89 was found to improve the seed germination under submerged conditions and also enhanced the tolerance to drought stress throughout growth stage. Additionally, OsEBP89 knockout rice plants increased the accumulation of proline, improved the ability to scavenge ROS compared to overexpression lines and wild type after PEG treatment. Transcriptome data indicates that knockout of OsEBP89 improved the expression of specific genes in response to adverse factors, such as OsAPX1, OsHsfA3, and OsP5CS. Further results indicate that OsEBP89 can interact with and be phosphorylated by SnRK1α (sucrose non-fermenting-1-related protein kinase-1 gene). These findings provide insight into the mechanism of abiotic stress tolerance, and suggest OsEBP89 as a new genetic engineering resource to improve abiotic stress tolerance in rice.

The metal-organic frameworks (MIL-125) were synthesized by the solvothermal method and the experimental parameters of preparation, purification and activation were optimized and the physicochemical properties were characterized. The adsorption capacity of MIL-125 on C8 aromatics was tested by the intelligent gravimetric analyzer (IGA) and the toluene vapor static adsorption device. The adsorption selectivity was studied by liquid static adsorption equilibrium experiment and large-scale pulse test. The C8 aromatics adsorption conformation and adsorption heat in MIL-125 was simulated by Materials Studio software. The characterization results show that the synthesized sample has excellent crystallinity, regular morphology with a grain size of about 1 ​μm, surface area of 1315 ​m2/g, micropore volume of 0.601 ​mL/g and a bulk density of 0.45 ​g/mL. Moreover, the vapor static adsorption results show that the synthesized sample has almost three times of adsorption capacity as large as BaX zeolite and the liquid dynamic adsorption results indicate the synthesized sample is preferentially selective to pare-xylene with the alkane desorbent. The simulation results show that the adsorption heat of pare-xylene in the synthesized sample and the binding energy of pare-xylene in the tetrahedral cage are the largest among these four isomers.

Haploids and doubled haploids are critical components of plant breeding. This review is focused on studies on haploids and double haploids inducted in cucurbits through in vitro pollination with irradiated pollen, unfertilized ovule/ovary culture, and anther/microspore culture during the last 30 years, as well as comprehensive analysis of the main factors of each process and comparison between chromosome doubling and ploidy identification methods, with special focus on the application of double haploids in plant breeding and genetics. This review identifies existing problems affecting the efficiency of androgenesis, gynogenesis, and parthenogenesis in cucurbit species. Donor plant genotypes and surrounding environments, developmental stages of explants, culture media, stress factors, and chromosome doubling and ploidy identification are compared at length and discussed as methodologies and protocols for androgenesis, gynogenesis, and parthenogenesis in haploid and double haploid production technologies.

Hierarchical MCM-49 zeolite with intracrystalline mesopores was prepared through post-treating the conventional MCM-49 zeolite in hexadecyltrimethylammonium bromide (CTAB) and NaOH mixed solution. N2 adsorption and desorption, XRD, TEM, XRF, ICP and Py-IR techniques were applied to characterize the obtained samples. It was found that uniform intracrystalline mesopores were distributed in the MCM-49 crystals, and the intracrystalline meso-porosity could be modified by changing the post-treatment conditions such as CTAB concentration, NaOH concentration, temperature and time. Based on the characterization results upon the hierarchical MCM-49 zeolite samples obtained by post-treating different time, the formation of intracrystalline mesopores in MCM-49 zeolite was proposed, which followed a CTAB micelle directed desilication mechanism. By virtue of the intracrystalline mesopores, the hierarchical MCM-49 zeolite prepared under proper post-treatment condition exhibited superior stability than the conventional MCM-49 zeolite in liquid alkylation of benzene with ethylene.

In this study, polysulfone (PSf) nano-hybrid membranes have been successfully fabricated by loading modified multi-walled carbon nanotubes (MWCNTs) as the dispersed phase using the phase inversion method. MWCNTs were chemically functionalized with polyethylene glycol (PEG) to achieve better dispersion in the polymer matrix. PEG-g-CNTs were confirmed by ATR-FTIR and XPS spectroscopy. The hybrid membranes showed better hydrophilicity, higher pure water flux and more excellent antifouling properties. The results demonstrated that the membrane containing 1.5 wt% PEG-g-MWCNTs showed the lowest contact angle (53.9°) and the highest water flux (71.26 L m−2 h−1) which was significantly higher than that of the pure PSf membrane and MWCNTs/PSf membrane. In BSA filtration analysis, the modified MWCNTs led to significant improvement of the fouling recovery ratio (FRR) and dramatic reduction of the adsorption amount of BSA. In addition, membranes exhibited excellent tensile strength after the addition of PEG-g-MWCNTs.

Support vector machine (SVM) algorithms were introduced to analyze the quality of seawater, and two models were constructed to analyze different seawater qualities, one is the SVM model for recognizing two kinds of seawater and the other is hierarchical support vector machines (H-SVMs) model for recognizing multi-seawater. The decision function of the first model for recognizing two kinds of seawater was applied to assess the unknown seawater samples. The trial results were consistent with the expected. It could be concluded that the parameter w in the decision functions is able to describe the weights of evaluation indices of seawater quality, which is much easier to determine the weights than fuzzy synthesis assessment (FSA). All show that SVM are based on a strict mathematical theory with a simple structure and a good generalization performance, which are worth being studied to assess seawater quality.