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Metal-backboned polymers with anisotropy microstructures are promising for conductive, optoelectronic, and magnetic functional materials. However, the structure-property relationships governing the interplay between the chemical structure and electromagnetic property of the metal-backboned polymer have been rarely investigated. Here we report a carbon/nickel hybrid from metal-backboned polymer to serve as electromagnetic wave-absorbing materials, which exhibit high microwave absorption capacity and tunable absorption band. The presence of nickel backbones promote the generation of heterogeneous interfaces with carbon during calcination, thereby enhancing the wave-absorbing capacity of the carbon/nickel hybrid. The C/Ni hybrids show a minimal reflection loss of −49.1 dB at 13.04 GHz, and its frequency of the absorption band can be adjusted by controlling the thickness of the absorption layer. [ABSTRACT FROM AUTHOR]

The microstructure of nickel-based single-crystal (SC) superalloys has a pivotal influence on their creep properties. The addition of the Re element not only enhances the long-term creep properties of nickel-based SC superalloys, but also results in the formation of a topologically close-packed (TCP) phase which is a harmful and brittle hard phase. Here, high-temperature creep interruption tests of a nickel-based SC superalloy that contains 4.8 wt% Re were performed under various temperatures and stress conditions, and the evolution of microstructure during creep was observed by scanning electron microscopy (SEM). The volume fraction of the TCP phase was also extracted to explore the mechanism that controls the impacts of the TCP phase on the creep properties. According to the microstructure evolution mechanism, the influence of the TCP phase was attributed to the initial damage and critical shear stress of the material. A creep performance prediction model for nickel-based SC superalloys considering the precipitation of the TCP phase that is based on the crystal plasticity theory and a modified creep damage model was established. The simulation curves fit well with the experimental results and the errors between prediction creep life with test results are within 5%. [ABSTRACT FROM AUTHOR]

This paper has demonstrated the resonance fluorescence enhancement of R6G when gold nanoparticles (Au NPs) deposited in the porous Si photonic crystal device. Both of microcavity (MC) and distributed Bragg reflector (DBR) with different parameters are investigated for making the photon transmission of photonic crystal device play an optimal role in enhancing fluorescence resonance. While minor changes were observed on the DBR substrates, a significant change in the intensity of enhanced fluorescence varies with the defect modes of MC substrates. Particularly, the strongest enhancement has been presented as the MC defect mode wavelength located at the maximum absorption wavelength of Au NPs. In this case, the fluorescence intensity of R6G on MC device is 2.5 times of that of R6G based on DBR device. [ABSTRACT FROM AUTHOR]

Autophagy is a sophisticated mechanism for maintaining cellular homeostasis, in which E1-like enzyme (ATG7) controls the activation of ubiquitin-like conjugation system in the autophagy pathway. In the insect pathogenic fungus Beauveria bassiana, a yeast ortholog of ATG7 was identified and functionally analyzed. Ablation of BbATG7 gene blocks the autophagic process under starvation stress. The mutant ΔBbATG7 exhibited impaired growth on the media with chitin as single nitrogen source. On rich media, gene loss did not cause notable effect on vegetative growth, but resulted in a considerable reduction in conidiation (71.6%) and blastospore yield (61.1%) in the mutant. In addition, the ΔBbATG7 mutant displayed increased sensitivity to stress caused by menadione and Congo red. The virulence of ΔBbATG7 mutant was significantly attenuated as indicated in topical and intrahemocoel injection assays. Our study indicates that BbATG7 contributes to B. bassiana virulence via regulating autophagy pathway and playing non-autophagic functions in the infection cycle. [ABSTRACT FROM AUTHOR]

In this paper, we mainly study the preparation of an optical biosensor based on porous silicon (PSi) Bragg mirror and its feasibility for biological detection. The quantum dot (QD) labeled biotin was pipetted onto streptavidin functionalized PSi Bragg mirror samples, the affinity reaction between QD labeled biotin and streptavidin in PSi occurred, so the QDs were indirectly connected to the PSi. The fluorescence of QD enhanced the signal of biological reactions in PSi. The performance of the sensor is verified by detecting the fluorescence of the QD in PSi. Due to the fluorescence intensity of the QDs can be enhanced by PSi Bragg mirror, the sensitivity of the PSi optical biosensor will be improved. [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) infection varies in the outcomes depending on both viral and host factors. This study aims to investigate the associations of three single nucleotide polymorphisms (SNPs) of Toll-like receptor 7 (TLR7), rs179016, rs5743733, and rs1634323, with susceptibility to HCV infection and clearance. The three SNPs were genotyped in a high-risk Chinese population, including 444 HCV spontaneous clearance cases, 732 persistent infection cases, and 1107 healthy controls. The G allele of rs1634323 was related to the protection from persistent infection among females (dominant model: odds ratio (OR) = 0.558, 95 % confidence interval (CI) = 0.348-0.894, P = 0.015). This protective effect was more evident in blood donation and HCV non-1 genotype-infected subgroups (all P < 0.05). The carriage of rs179016 C allele was more prone to develop persistent infection (OR = 1.444, 95 % CI = 1.096-1.903, P = 0.009) in males, and the risk effect remained significant among older (>50 years), hemodialysis (HD), and HCV-1 and HCV non-1 genotypes-infected subjects (all P < 0.05). Haplotype analyses showed that CCA haplotype among females was correlated with the elevated risk of HCV susceptibility while the carriage of GGA was more prone to be infected with HCV and CCA was more likely to develop persistent infection (all P < 0.05) among males. Our results first demonstrated that the carriage of rs179016 C allele had a negative effect on spontaneous clearance of HCV among males while rs1634323 G allele conferred a protective effect against persistent infection among female subjects. [ABSTRACT FROM AUTHOR]

A new chelating resin (CPS-DMA-SABA) was synthesized with the chloromethylated cross-linked polystyrene porous beads (CPS) as raw materials, which were bonded with salicylidene- o-aminobenzoic acid (SABA) on the surface via a quaternary ammonium unit as a linker. The results showed that CPS-DMA-SABA would easily change into a zwitterionic chelating resin (CPS-DMA-SABZ) when washed with distilled water. CPS-DMA-SABA was characterized by elemental analysis, infrared spectra and thermo-gravimetric analysis. The ion sorption capacities of CPS-DMA-SABA were found to be 1916 μg/g for Zn with pH at 4.5, 1620 μg/g for Cu with pH at 6.2, 1291 μg/g for Ni with pH at 6.6 and 780 μg/g for Cr with pH at 5.5, respectively. The experiments showed CPS-DMA-SABA also changed its color when meeting with the metal ion in the aqueous solution. As a consequence, CPS-DMA-SABA can not only be used as a solid phase extractant but also an indicator for confirming the heavy metal ion in solutions. [ABSTRACT FROM AUTHOR]

To analyze the feasibility of utilization of thermal technology in fly ash treatment, thermal properties and microstructures of municipal solid waste incineration (MSWI) fly ash were studied by measuring the chemical element composition, specific surface area, pore sizes, functional groups, TEM image, mineralogy and DSC-TG curves of raw and sintered fly ash specimens. The results show that MSWI fly ash particles mostly have irregular shapes and non-typical pore structure, and the supersonic treatment improves the pore structure; MSWI fly ash consists of such crystals as SiO, CaSO and silica-aluminates, and some soluble salts like KCl and NaCl. During the sintering process, mineralogy changes largely and novel solid solutions are produced gradually with the rise of temperature. Therefore, the utilization of a proper thermal technology not only destructs those persistent organic toxicants but also stabilizes hazardous heavy metals in MSWI fly ash. [ABSTRACT FROM AUTHOR]

Thom–Pontrjagin constructions are used to give a computable necessary and sufficient condition for a homomorphism ϕ : H[sup n](L;Z) → H[sup n](M;Z) to be realized by a map f : M → L of degree k for closed (n - 1)-connected 2n-manifolds M and L, n > 1. A corollary is that each (n - 1)-connected 2n-manifold admits selfmaps of degree larger than 1, n > 1. In the most interesting case of dimension 4, with the additional surgery arguments we give a necessary and sufficient condition for the existence of a degree k map from a closed orientable 4-manifold M to a closed simply connected 4-manifold L in terms of their intersection forms; in particular, there is a map f : M → L of degree 1 if and only if the intersection form of L is isomorphic to a direct summand of that of M. [ABSTRACT FROM AUTHOR]

We sequenced and annotated the first complete mitochondrial genome (mitogenome) of Ledra auditura (Hemiptera: Cicadellidae: Ledrinae) and reconstructed phylogenetic relationships among 47 species (including 2 outgroup species) on the basis of 3 datasets using maximum likelihood (ML) and Bayesian inference (BI) analyses. The complete L. auditura mitogenome (length, 16,094 bp) comprises 37 genes [13 protein-coding genes (PCGs), 22 tRNAs, and 2 rRNAs], 1 control region, and 2 long non-coding regions. The first long non-coding region (length, 211 bp) is located between tRNA-I and tRNA-Q and the second region (length, 994 bp) between tRNA-S2 and ND1. All PCGs show ATN (Met/Ile) as their start codon and TAR as their stop codon. Except tRNA-S1 (AGN), which lacks the dihydrouridine arm, all tRNAs can fold into the typical cloverleaf secondary structure. The complete L. auditura mitogenome shows a base composition bias of 76.3% A + T (A = 29.9%, T = 46.4%, G = 13.3%, and C = 10.5%), negative AT skew of −0.22, and positive GC skew of 0.12. In ML and BI analyses, L. auditura was clustered with Evacanthus heimianus (Hemiptera: Cicadellidae: Evacanthinae) with strong branch support. [ABSTRACT FROM AUTHOR]