Search

Domesticated grapevines spread to Europe around 3,000 years ago. Previous studies have revealed genomic signals of introgression from wild to cultivated grapes in Europe, but the time, mode, genomic pattern, and biological effects of these introgression events have not been investigated. Here, we studied resequencing data from 345 samples spanning the distributional range of wild (Vitis vinifera ssp. sylvestris) and cultivated (V. vinifera ssp. vinifera) grapes. Based on machine learning-based population genetic analyses, we detected evidence for a single domestication of grapevine, followed by continuous gene flow between European wild grapes (EU) and cultivated grapes over the past ~2,000 y, especially from EU to wine grapes. We also inferred that soft-selective sweeps were the dominant signals of artificial selection. Gene pathways associated with the synthesis of aromatic compounds were enriched in regions that were both selected and introgressed, suggesting EU wild grapes were an important resource for improving the flavor of cultivated grapes. Despite the potential benefits of introgression in grape improvement, the introgressed fragments introduced a higher deleterious burden, with most deleterious SNPs and structural variants hidden in a heterozygous state. Cultivated wine grapes have benefited from adaptive introgression with wild grapes, but introgression has also increased the genetic load. In general, our study of beneficial and harmful effects of introgression is critical for genomic breeding of grapevine to take advantage of wild resources. [ABSTRACT FROM AUTHOR]

The present meta-analysis aimed to evaluate metformin combined with acarbose compared with monotherapy with either of the two drugs for type 2 diabetes (T2DM). Relevant trials were retrieved through searching PubMed, Embase, Cochrane library, China National Knowledge Infrastructure, Wanfang and Chongqing VIP information network databases. Heterogeneous and homogeneous data were statistically combined using a random- and fixed-effects model, respectively. For dichotomous and continuous data, the merged effect size was presented as the risk ratio (RR) and weighted mean differences (WMD), respectively, with 95% confidence interval (CI). All included studies were divided into subgroups. A Funnel plot was used to detect publication bias. Review Manager 5.2 software was applied to perform the statistical analyses. Meta-analysis revealed that compared with metformin monotherapy, combined therapy was significantly more efficacious regarding indexes including the total effective rate, fasting blood glucose (FBG), blood glucose levels at two post-prandial hours (2HPG) and hemoglobin A1C (HbA1c). Similarly, combined therapy showed advantages on indexes including FBG, 2HPG and HbA1c over acarbose therapy after 4 months of treatment. In conclusion, the findings of the present meta-analysis suggested that combined therapy of metformin and acarbose appears to be more efficacious than metformin or acarbose monotherapy. [ABSTRACT FROM AUTHOR]

In this paper, we prove that on an oriented smooth closed surface, a vector field has the (C¹) robustly weak shadowing property if and only if it is structurally stable. [ABSTRACT FROM AUTHOR]

We report a group of new DNA enzymes that possess a synchronized RNA-cleavage/ fluorescence-signaling ability and exhibit wide-ranging metal-ion and pH dependences. These DNA catalysts were derived from a random-sequence DNA pool in a two-stage process: (1) establishment of a catalytic DNA population through repetitive rounds of in vitro selection at pH 4.0, and (2) sequence-diversification and catalytic-activity optimization through five parallel paths of in vitro evolution conducted at pH 3.0, 4.0, 5.0, 6.0, and 7.0, respectively. The deoxyribozymes were evolved to cleave the phosphodiester bond of a single ribonucleotide embedded in DNA and flanked immediately by two deoxyribonucleotides modified with a fluorophore and a quencher, respectively—a setting that synchronizes catalysis with fluorescence signaling. The most dominant catalyst from each pool was examined for metal-ion specificity, catalytic efficiency, pH dependence, and fluorescence-signaling capability. Individual catalysts have different metalion requirements and can generate as much as a 12-fold fluorescence enhancement upon RNA cleavage. Most of the DNA enzymes have a pH optimum coinciding with the selection pH and exhibit a rate constant approximating 1 min[sup -1] under optimal reaction conditions. The demonstration of DNA enzymes that are functional under extremely high acidity (such as pH 3 and 4) indicates that DNA has the ability to perform efficient catalysis even under harsh reaction conditions. The isolation of many new signaling DNA enzymes with broad pH optima and metal-ion specificities should facilitate the development of diverse deoxyribozymebased biosensors. [ABSTRACT FROM AUTHOR]

DNA enzymes are single-stranded DNA molecules with catalytic capabilities that are isolated from random-sequence DNA libraries by "in vitro selection". This new class of catalytic biomolecules has the potential of being used as unique molecular tools in a variety of innovative applications. Here we describe the creation and characterization of an RNA-cleaving autocatalytic DNA, DEC22-18, that uniquely links chemical catalysis with real-time fluorescence signaling capability in the same molecule. A trans-acting DNA molecule, DET22-18, was also developed from DEC22-18 that behaves as a true enzyme with a k[sub cat] of ∼7 min[sup -1]—a rate constant that is the second largest ever reported for a DNA enzyme. It cleaves a chimeric RNA/DNA substrate at the lone RNA linkage surrounded by a closely spaced fluorophore-quencher pair a unique structure that permits the synchronization of the chemical cleavage with fluorescence signaling. DET22-18 has a stem-loop structure and can be conjugated with DNA aptamers to form allosteric deoxyribozyme biosensors. [ABSTRACT FROM AUTHOR]

Haploid seedlings were inducted from different maize materials. At 2-3-leaf stage, maize haploids were treated with 0.06% colchicine and 2.0% dimethyl sulfoxide (DMSO) by dipping root, dripping heart leaf and acupuncturing growing point, respectively. The doubling rate and mortality rate in different treatments were analyzed by variance analysis and multiple comparisons. The result showed that growing point acupuncturing method exhibited the highest doubling efficiency with an average doubling rate of 23%, seed-setting rate of 21.4%, and mortality rate of 16.3%. Composed with other two chemical doubling methods, growing point acupuncturing method significantly improved the doubling rate of maize haploids with a lower application dose of colchicine. This study laid the foundation for industrial application of haploid breeding techniques. [ABSTRACT FROM AUTHOR]

A neutron bang time (NBT) diagnostic system has been implemented on Shenguang-III prototype. The bang time diagnostic system is based on a sensitive fusion neutron detector, which consists of a plastic scintillator and a micro-channel plate photomultiplier tube (PMT). An optical fiber bundle is used to couple the scintillator and the PMT. The bang time system is able to measure bang time above a neutron yield of 107. Bang times and start time of laser were related by probing x-ray pulses produced by 200 ps laser irradiating golden targets. Timing accuracy of the NBT is better than 60 ps. [ABSTRACT FROM AUTHOR]

The protein phosphatase 2C (PP2C) gene family is one of the momentous and conserved plant-specific gene families, known to participate in cellular processes via reversible protein phosphorylation and regulates signal transduction in eukaryotic organisms. Recently, PP2Cs were identified in Arabidopsis and maize, however, the whole-genome analysis of PP2C in strawberry has not yet been reported. In the current research, we found 62 PP2C -encoding genes in total from the strawberry genome. Further, the phylogenetic analysis categorized FvPP2C genes into twelve subgroups with significant structural conservation based on conserved domain and amino acid sequence. Moreover, we observed a strong signature of purifying selection between the comparison of orthologous gene pairs of strawberry and Arabidopsis. The comparison of RNA-sequence (RNA-seq) data published on various vegetative and reproductive tissues of strawberry plant suggested the significant role of FvPP2C genes in organ development. The q RT-PCR validation of thirty FvPP2C genes indicated their critical tolerance-related role under abiotic stress stimuli in strawberry. Finally, the subcellular localization of FvPP2C51 gene proves that it resides and stimulates its function in the nucleus. Our findings provide an overview of the identification of strawberry FvPP2C gene family and demonstrate their critical role in tissue-specific response and abiotic stress-tolerance, thereby, intimating their significance in the strawberry molecular breeding for the resistant cultivars. • Sixty-two FvPP2C genes were identified from woodland strawberry (Fragaria vesca L). • Most of the FvPP2C genes showed conserved domains and genome organization structure. • Thirty FVPP2C genes suggested dynamic expression profiling against various abiotic stress. • Gene ontology analysis predicted their functioning in cellular components, molecular function, and biological process. • Subcellular localization of FvPP2C51 in onion epidermal cells proved that it resides and performs function in the nucleus. [ABSTRACT FROM AUTHOR]

PEG 1000-based functional dicationic acidic ionic liquid (PEGI000-DAIL) was used for the first time as the reaction solvent for the N-Hydroxyphthalimide (NHPI)-cobalt acetate(Co(OAc)2) catalyzed aerobic oxidations of alkylaromatics to the corresponding acids. It enhanced the efficient catalytic ability of NHPI: 99.9 % conversion of toluene with 99.5 % selectivity for benzoic acid could be obtained at 80 ° C in 10 h and ethylbenzene was selectively oxidized to benzoic acid. Several alkylaromatics were efficiently oxidized to their corresponding acids under mild conditions. For substituted toluene, the conversions of substrates and the selectivity of products was affected by the position and kind of substituted groups, respectively. Both the catalyst and PEG1000-DAIL could be reused at least eight times without significantly decreasing the catalytic activity. [ABSTRACT FROM AUTHOR]