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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.

Increasing agricultural productivity is one of the most important goals of plant science research and imperative to meet the needs of a rapidly growing population. Rice (Oryza sativa L.) is one of the most important staple crops worldwide. Grain size is both a major determinant of grain yield in rice and a target trait for domestication and artificial breeding. Here, a genome-wide association study of grain length and grain width was performed using 996,722 SNP markers in 270 rice accessions. Five and four quantitative trait loci were identified for grain length and grain width, respectively. In particular, the novel grain size gene OsSNB was identified from qGW7, and further results showed that OsSNB negatively regulated grain size. Most notably, knockout mutant plants by CRISPR/Cas9 technology showed increased grain length, width, and weight, while overexpression of OsSNB yielded the opposite. Sequencing of this gene from the promoter to the 3’-untranslated region in 168 rice accessions from a wide geographic range identified eight haplotypes. Furthermore, Hap 3 has the highest grain width discovered in japonica subspecies. Compared to other haplotypes, Hap 3 has a 225 bp insertion in the promoter. Based on the difference between Hap 3 and other haplotypes, OsSNB_Indel2 was designed as a functional marker for the improvement of rice grain width. This could be directly used to assist selection toward an improvement of grain width. These findings suggest OsSNB as useful for further improvements in yield characteristics in most cultivars., Author summary Grain weight, including grain length and grain width, is a complex trait, and hundreds of quantitative trait loci (QTLs) were detected in different genetic rice populations. However, only about 10 genes have been isolated and characterized until now. Nine QTLs for grain size were identified by genome-wide association study in a natural rice population. The novel grain size gene OsSNB was identified from qGW7 based on the difference of expression levels between two different varieties with significantly different grain width. OsSNB is an AP2 transcription factor that is negatively regulated grain size. However, OsSNB was found to regulate the transition from the spikelet meristem to the floral meristem and the floral organ development in previous study. Compared to other haplotypes, Hap 3 has a 225 bp insertion in the promoter. Based on the difference between Hap 3 and other haplotypes, OsSNB_Indel2 was designed as a functional marker for the improvement of rice grain width. This can be directly used to assist selection for grain width improvement.

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.

Objective: Several published studies have investigated the association between the −308G/A (rs1800629) polymorphism in the tumor necrosis factor-α (TNF-α) gene and the risk of dilated cardiomyopathy (DCM). However, the TNF-α gene polymorphism has a controversial role in the pathogenesis of DCM among different populations. In the present study, a meta-analysis was performed to resolve this inconsistency. Methods: Potentially eligible papers reporting an association between the TNF-α rs1800629 polymorphism and DCM susceptibility were searched in 4 databases including PubMed, EMBASE, Chinese Biomedical Database (CBM), and the Cochrane Library up to April 1, 2018. The odds ratio (OR) with its 95% confidence interval (CI) was used to estimate the strength of the associations. Subgroup analysis based on the ethnicity, studies with or without ischemic and valvular DCM was conducted. Publication bias detection was conducted using Begg test. Results: Nine papers detailing case-control studies were included, reporting a total of 1339 DCM cases and 1677 healthy controls. The meta-analysis results indicated that TNF-α rs1800629 was associated with increased DCM susceptibility in the populations studied under the heterozygous model (AG vs GG: OR = 1.91, 95% CI = 1.05−3.50, P = .035) and dominant model (AG + AA vs GG: OR = 1.87, 95% CI = 1.01−3.45, P = .046). In the subgroup analysis for ethnicity, rs1800629 polymorphism was significantly associated with the susceptibility of DCM for Asians under the 5 models (A vs G: OR = 2.87, 95% CI = 1.56−5.30, P = .001; AA vs GG: OR = 3.95, 95% CI = 1.13−13.82, P = 0.031; AG vs GG: OR = 3.8, 95% CI = 1.57−9.19, P = .003; AA vs GG + AG: OR = 2.51, 95% CI = 1.41−4.49, P = .002; AG + AA vs GG: OR = 3.77, 95% CI = 1.54−9.20, P = .004). Conclusion: There may be a moderate association between TNF-α rs1800629 polymorphism and DCM susceptibility in the whole populations studied; however, TNF-α rs1800629 polymorphism was significantly associated with the susceptibility of DCM for Asians, which indicates that such associations may be different between ethnicities.

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.

Ginkbilobin is a short antifungal protein that had been cloned from the seeds of Ginkgo biloba. We show that ginkbilobin binds to the actin cytoskeleton. And the binding of actin efficiently induces cell death. We discuss these findings in terms of a working model, where ginkbilobin can interfere with the actin cytoskeleton of the target cell to activate an evolutionarily conserved apoptotic pathway.

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.