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Inulavosin, a natural melanogenesis inhibitor, has been synthesized smoothly from readily available and inexpensive starting materials by using a Ga(OTf)3-catalyzed room temperature hetero Diels–Alder dimerization of salicyl alcohol derivative and a regioselective phenol monobromination as the key steps. [ABSTRACT FROM AUTHOR]

El Niño has two different flavors, eastern Pacific (EP) and central Pacific (CP) El Niños, with different global teleconnections. However, their different impacts on the interannual carbon cycle variability remain unclear. Here we compared the behaviors of interannual atmospheric CO2 variability and analyzed their terrestrial mechanisms duringthese two types of El Niños, based on the Mauna Loa (MLO) CO2 growth rate (CGR) and the Dynamic Global Vegetation Model's (DGVM) historical simulations. The composite analysis showed that evolution of the MLO CGR anomaly during EP and CP El Niños had three clear differences: (1) negative or neutral precursors in the boreal spring during anEl Niño developing year (denoted as "yr0"), (2) strong or weak amplitudes, and (3) durations of the peak from December (yr0) to April during an El Niño decaying year (denoted as "yr1") compared to October (yr0) to January (yr1) for a CP El Niño, respectively. The global land-atmosphere carbon flux (FTA) simulated by multi-models was able to capture the essentials of these characteristics. We further found that the gross primary productivity (GPP) over the tropics and the extratropical Southern Hemisphere (TropCSH) generally dominated the global FTA variations during both El Niño types. Regional analysis showed that during EP El Niño events significant anomalous carbon uptake caused by increased precipitation and colder temperatures, corresponding to the negative precursor, occurred between 30°S and 20°N from January (yr0) to June (yr0). The strongest anomalous carbon releases, largely due to the reduced GPP induced by low precipitation and warm temperatures, occurred between the equator and 20°N from February (yr1) to August (yr1). In contrast, during CP El Niño events, clear carbon releases existed between 10°N and 20°S from September (yr0) to September (yr1), resulting from the widespread dry and warm climate conditions. Different spatial patterns of land temperatures and precipitation in different seasons associated with EP and CP El Niños accounted for the evolutionary characteristics of GPP, terrestrial ecosystem respiration (TER), and the resultant FTA. Understanding these different behaviors of interannual atmospheric CO2 variability, along with their terrestrial mechanisms during EP and CP El Niños, is important because the CP El Niño occurrence rate might increase under global warming. [ABSTRACT FROM AUTHOR]

Summary: WRKY transcription factors are known to participate in the defence responses of higher plants. However, little is known about the roles of such proteins, especially regarding their functions in the resistance of oilseed rape (Brassica napus) to Sclerotinia sclerotiorum, a necrotrophic fungal pathogen that causes stem rot. In this study, we identified BnWRKY33 as a S. sclerotiorum‐responsive gene that positively regulates resistance to this pathogen by enhancing the expression of genes involved in camalexin synthesis and genes regulated by salicylic acid (SA) and jasmonic acid (JA). We also identified a S. sclerotiorum‐responsive region in the promoter of BnWRKY33, which we revealed to be a relatively conserved W‐box region in the promoters of homologous genes in different species. Using this S. sclerotiorum‐responsive region as bait in a yeast one‐hybrid assay, we identified another WRKY transcription factor, BnWRKY15, and observed that both BnWRKY15 and BnWRKY33 could bind to this region. In addition, BnWRKY15 overexpression simultaneously increased the susceptibility of B. napus to S. sclerotiorum and down‐regulated BnWRKY33 after different durations of infection. Furthermore, BnWRKY15, which contains a transcriptional repression domain, exhibited reduced transactivation ability and could reduce the transactivation ability of BnWRKY33 in Arabidopsis protoplast assays. Therefore, we suggest that the increased susceptibility of BnWRKY15‐overexpressing plants results from reduced BnWRKY33 expression, which is due to the inhibition of BnWRKY33 transcriptional activation by BnWRKY15. [ABSTRACT FROM AUTHOR]

A facile spinning-based strategy was developed to fabricate chitosan (CS) surface nanofiber-based affinity membranes for protein adsorption. The core-shell nanofiber mat of nylon 6-CS was prepared via coaxial solution blowing process. The nanofibers have a diameter range of 60-300 nm. The core-shell structure was confirmed by transmission electron microscopy, and CS was observed as a thin layer that uniformly adhered to the core. The dye ligand of cibacron blue F3GA (CB F3GA) was further covalently immobilized on the nanofibers with a content of 425 µmol/g. The pristine and CB F3GA-attached mats were studied in protein adsorption. High bovine serum albumin adsorption capacities of 91.9 and 219.6 mg/g were obtained for pristine and CB F3GA-attached mats, respectively. Given its properties of high flux rate and low pressure drop, CB F3GA-attached nylon 6-CS nanofiber mat meets the requirements of highly effective affinity membrane chromatography. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A non-enzymatic glucose sensor, based on the silver nanoparticles (Ag-NPs)/poly ( o -phenylenediamine) (PoPD) composites, is developed by the electrochemical polymerization of o -phenylenediamine and electrodeposition of silver nanoparticles on an indium tin oxide electrode. The Ag-NPs/PoPD composites are characterized by atomic force microscopy, scanning electronic microscopy and energy dispersive spectrometer. Under the optimized experimental conditions, the proposed glucose sensor demonstrates a wide linear range from 0.15 to 13 mmol L − 1 with a correlation coefficient of 0.998. The proposed glucose sensor can be used to detect glucose in blood sample with a satisfactory result. In addition, the proposed sensor presents the advantages, such as facile preparation, low cost, high sensitivity and fast response time. It also exhibits good anti-interference performance and stability. [ABSTRACT FROM AUTHOR]

ABSTRACT Multimode fiber Bragg grating (MFBG) is inscribed in graded-index multimode fiber using infrared femtosecond laser and phase mask. Multiple dips are observed in the transmission spectrum of MFBG. There is not only self-coupling effect between the forward and backward principal modes, but also the mutual coupling effect between the neighbor modes. The induced refractive index modulation of 6.4 × 10 −4 is achieved for a peak power density of 4.1 × 1013 W/cm2 without any fiber sensitization. Thermal experiment results show that the MFBG belongs to type I grating. The transmission spectrum of MFBG shifts linearly with the strain and pressure at sensitivities of 1.27 ± 0.002 pm/με and −3.3 ± 0.06 pm/MPa, respectively. The MFBGs are expected to be used for multichannel filters, multiwavelength fiber lasers, and multiparameter sensing. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:214-219, 2017 [ABSTRACT FROM AUTHOR]

Geopolymer with Si/Al ratios from 2 to 4 were prepared by adding different contents of fused silica into geopolymer matrix. Effects of Si/Al ratios on the structure, mechanical properties and chemical stability in air of the obtained geopolymer were systematically investigated. The results showed that all the geopolymer samples were XRD amorphous. Geopolymer with Si/Al ratios of 2 and 2.5 showed similar structure and property and they were classed as KGP-I; and geopolymer with Si/Al ratios of 3, 3.5 and 4 were similar and they were class as KGP-II. In alkaline solution, reactivity of fused silica were higher than that of metakaolin, resulting in higher content of both residual metakaolin and free alkaline cation in KGP-II than in KGP-I. Fused silica partially reacted with the alkaline solution in KGP-II indicating chemical interfacial bonding between silica and binder phase. With the increase in Si/Al ratios, KGP-II especially for geopolymer with Si/Al of 4 showed much higher mechanical properties than KGP-I due to the increased Si-O-Si bonds and residual silica as reinforcement. However, KGP-II showed worse chemical stability in air than KGP-I, with the presence of efflorescence on the surface, which was attributed to their higher residual free K + . [ABSTRACT FROM AUTHOR]