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The surface of poly (p-phenylene benzobisoxazole) (PBO) fibers with self-healing and ultraviolet (UV)-resistance performance play the key role in prolonging their service lifespan. Although great advances have been made in the single aspect of above two properties, integration of self-healing and anti-UV performance into the surface of PBO fiber is still a challenge. In this study, the coagulation strategy mediated by metal-organic framework (MOF) is proposed to construct the multifunctional surface of PBO fibers. The spindle-like iron (III)-based MOF (MIL-88B-NH 2) nanocrystals are firstly immobilized onto the surface of PBO-COOH through hydrothermal reaction, then serving as the medium layer to further immobilize sufficient graphene oxide (GO) nanosheets. Benefitting from the favorable near-infrared (NIR, 808 nm) photothermal conversion performance of GO nanolayers, the monofilament composite-PBO@Fe-MIL-88B-NH 2 -GO-TPU (thermoplastic polyurethane) exhibited a stable and high self-healing efficiency (approximately 80%) within five cycle times. Meanwhile, the cooperative adsorption and shielding weaken effects of MOF-GO nanolayers enabled PBO fibers with excellent anti-UV properties that are superior to much reported literatures after 96 h aging time and eventually increased by 75% compared with untreated PBO fiber. In view of the varieties and multifunctionalities of MOFs and carbon nanomaterials, MOF-mediated coagulation strategy would provide guidance for preparing multifunctional composite materials. [ABSTRACT FROM AUTHOR]

Rice, the most consumed in Asian and constitute important source of amino acids. The present study evaluated the suitability of near-infrared reflectance spectroscopy to predict amino acid contents (AACs) using 1210 rice samples representing a wide range of grain qualities and genetic background. Calibration models established by combining different spectral derivatives, scatter and baseline correction methods, and regression algorithm were compared using full cross validation. A modified partial least square model (MPLS) with the spectral derivative treatment "2, 3, 3, 1" (2nd order derivative computed based on 3 data points, and 3 and 1 data points in the 1st and 2nd smoothing, respectively) and weighted multiplicative scattering correction (WMSC) method was identified as the best model for simultaneously measurement of 14 AACs in brown rice flour. The high model quality is reflected by RSQ of 0.914∼0.969, standard error of calibration (SEC) of 0.0187%∼0.0553%, 1-VR of 0.901∼0.955, SECV of 0.0214%∼0.0579%, and residual prediction deviation (RPD) of 2.58∼3.85. These results indicated that NIRS coupled with an appropriate pre-processing, multivariate regression could be a rapid and reliable method for quantification of AACs in rice breeding programs and quality control in the food industry. Factors that would influence model quality were investigated and discussed. • NIRS is capable of accurately quantifying 14 amino acids contents in diverse rice samples. • MPLS was the most robust regression method. • MSC and 2nd derivation were suitable pre-processing methods. • NIRS is applicable for high-throughput screening. [ABSTRACT FROM AUTHOR]

An anionic bio-MOF-1 with 1D square channels is applied as container for the adsorption of organic dyes owing to the porous structure and charge properties. Through ion exchange, cationic acriflavine (Acf) dye with the minimum size is selected as a fluorescent dye molecule to introduce into the pores of anionic bio-MOF-1 to obtain a self-calibrating dual-emitting fluorescent composite of Acf@bio-MOF-1, which exhibits two characteristic emission peaks at 385 and 582 ​nm. The composite acts as fluorescence sensing probe for the selective and sensitive detection of Fe3+, Al3+ and Cr 2 O 7 2− among metal cations and anions and has a "turn-off" response to Fe3+ and Cr 2 O 7 2− as well as a "turn-on" response to Al3+ at the same time. Particularly, Acf@bio-MOF-1 shows higher fluorescence quenching effects of 95% for Cr 2 O 7 2− and 90% for Fe3+ and low detection limits of 0.25 ​μM for Cr 2 O 7 2− and 1.33 ​μM for Fe3+, respectively. Such a special encapsulation strategy to form a dual-emission platform can be adopted to the detection of inorganic ions sensitively. A fluorescent dye acriflavine (Acf) was encapsulated into anionic bio-MOF-1 to form a dual-emission fluorescence sensing probe for the detection of Fe3+, Al3+ and Cr 2 O 7 2− among metal ions and anions selectively and sensitively. Image 1 • A new self-calibrating dual-emitting fluorescent composite Acf@bio-MOF-1 was prepared. • Acf@bio-MOF-1 shows high fluorescence quenching effects for Fe3+ and Cr 2 O 7 2−, respectively. • Acf@bio-MOF-1 shows a unique "turn-on" response to Al3+ in all selected metal ions. [ABSTRACT FROM AUTHOR]

Abstract: Poxviruses currently are known to disrupt Jak-STAT signal transduction induced by interferon (IFN) through two distinct mechanisms: (1) secreted poxviral IFN decoy receptors that prevent the initiation of IFN signaling from type I or II receptors at the cell surface; and (2) poxviral phosphatase that dephosphorylates STAT1 intracellularly. Here, we report a novel mechanism by which poxviruses can inhibit Jak-STAT signaling in response to type I IFN. Myxoma virus (MV) is a highly species-restricted member of the poxvirus family that infects only rabbits under the natural setting. Interestingly, primary human fibroblasts support a permissive MV infection that is only partially sensitive to the antiviral state induced by type I IFN. In this study we show that when type I IFN is added to primary human fibroblasts following MV infection, the tyrosine phosphorylation of the Janus kinase Tyk2 is specifically blocked, thereby preventing the subsequent activation of downstream STAT1 and STAT2. In stark contrast, type II IFN-induced activation of Jak1, Jak2 and STAT1 remains largely unaffected in MV-infected human fibroblasts. Unlike the de-activation of STAT1 by the poxvirus phosphatase, which is delivered into the cell by the input virions, the Tyk2 inhibition by MV infection requires new viral gene expression. Thus, our study documents a previously unrecognized immune evasion mechanism exploited by a poxvirus to selectively disrupt the type I IFN-Jak-STAT signaling cascade. [Copyright &y& Elsevier]