56 research outputs found
Method based on fast fourier transform for calculating conical refraction of beams with noncircular symmetry
Conical refraction of optical beams with circular symmetry is often analyzed using Belsky-Khapalyuk-Berry (BKB) theory; however, for beams with noncircular symmetry, it is difficult to obtain analytical expressions for far-field diffraction patterns. We propose a method, based on fast Fourier transform (FFT), for calculating conical refraction of beams with noncircular symmetry and verify it experimentally using a quasi-plane wave passing through a square aperture and focusing lens. Excellent agreement between theoretical and experimental results has been achieved
Purification, composition analysis and antioxidant activity of different polysaccharides from the fruiting bodies of Pholiota adiposa
Three water-soluble polysaccharide fractions (PAP1-1, PAP1-2 and PAP2-1) were isolated and purified from the fruiting bodies of Pholiota adiposa by diethylaminoethanol (DEAE) Sepharose fast flow column and superdexTM 200 column chromatography on an AKTA Purifier system. Results of high-performance size-exclusion chromatography (HPSEC) indicated that the average molecular weights of PAP1-1, PAP1-2 and PAP2-1 were 2.3 x 106 Da, 8.8 x 103 Da and 2.1 x 106 Da, respectively. Monosaccharide compositions analysis revealed that PAP1-1 and PAP2-1 were both mainly composed of glucose, and PAP1-2 was composed of rhamnose and glucose with a mole ratio of 1:3.61. The evaluation of antioxidant activity suggested that PAP1-1 with ÎČ-configuration glycosidic bond exhibited stronger scavenging activity of superoxide radical and hydroxyl radical than PAP1-2 and PAP2-1 contained both α- and ÎČ-configuration glycosidic bond, and should be explored as a novel potential antioxidant. Available data obtained with in vitro models suggested that antioxidant activity of polysaccharide may be related to the configuration of glycosidic bond.Key words: Pholiota adipose, polysaccharide, purification, antioxidant activity
Characterization of the Gene BmEm4, a Homologue of Drosophila E(spl)m4, from the Silkworm, Bombyx mori
The Drosophila E(spl)m4 gene contains some highly conserved motifs (such as the Brd box, GY box, K box, and CAAC motif) in its 3âČ untranslated region (3âČ UTR). It was shown to be a microRNA target gene in Drosophila and to play an important role in the regulation of neurogenesis. We identified a homologue of the E(spl)m4 gene from Bombyx mori called BmEm4 and examined the expression patterns of BmEm4 mRNA and protein. There was a lack of correlation in the expression of the mRNA and protein between the different developmental stages, which raises the possibility of posttranscriptional regulation of the BmEm4 mRNA. Consistent with this idea is the finding that the 3âČ UTR contains two putative binding sites for microRNAs. Moreover, given that the expression is the highest in the larval head, as confirmed by immunohistochemistry, we propose that BmEm4 may also be involved in the regulation of neurogenesis. Immunostaining indicated that BmEm4 is located primarily in the cytoplasm
Hierarchically Designed Germanium Microcubes with High Initial Coulombic Efficiency toward Highly Reversible Lithium Storage
Circ_0114427 promotes LPS-induced septic acute kidney injury by modulating miR-495-3p/TRAF6 through the NF-ÎșB pathway
Backgrounds Septic acute kidney injury (AKI) is a severe illness in clinics. Enriching researches investigated the regulatory network of AKI during the past decades, evidences showed that circular RNAs (circRNAs) were involved in the molecular mechanism of human AKI. However, the special responses remain largely elusive. Thus, the study aims to investigate the function of circ_0114427 in the progression of AKI. Methods The levels of circ_0114427, miR-495-3p and Tumour Necrosis Factor Receptor-Associated Factor 6 (TRAF6) were both assessed by quantitative real-time polymerase chain reaction (qRT-PCR). In addition, lipopolysaccharide (LPS) was applied to establish AKI cell model, and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay was carried out to determine the viability of LPS-induced HK-2 cells. The expression of TRAF6, B-cell lymphoma-2 (Bcl-2), Bcl2-associated X (Bax), cleave-caspase 3, caspase 3, total IÎșBα (t-IÎșBα), phospho-IÎșBα (p-IÎșBα), total p65 (t-p65) and phospho-p65 (p-p65) were all detected via western blot. The levels of IL-1ÎČ and TNF-α were identified by western blot and ELISA. Whatâs more, cell apoptosis was measured by flow cytometry. Lastly, dual-luciferase reporter, RNA Immunoprecipitation (RIP) and RNA pull-down assays were employed to verify the relationships between miR-495-3p and circ_0114427 or TRAF6 in vitro. Results The level of miR-495-3p was remarkably restrained while circ_0114427 and TRAF6 levels were specially reinforced in AKI patient serum samples and LPS-induced HK-2 cells. Moreover, IL-1ÎČ and TNF-α were highly expressed in LPS-induced AKI cells. Functionally, circ_0114427 was a sponge of miR-495-3p, and circ_0114427 silence-mediated effects in LPS-induced HK-2 cells were partly ameliorated by the addition of miR-495-3p inhibitor. Moreover, TRAF6 was a target gene of miR-495-3p, and the inhibiting effect of miR-495-3p on cell apoptosis and inflammatory response was mitigated by TRAF6 overexpression. Mechanistically, the circ_0114427/miR-495-3p/TRAF6 axis modulated cell apoptosis and inflammatory response via NF-ÎșB/p65 signalling pathway in AKI. Conclusion Circ_0114427 regulated cell apoptosis and inflammatory response through miR-495-3p/TRAF6 axis via NF-ÎșB/p65 signalling pathway, providing a novel mechanism in clinical treatment of AKI patients.Highlights Circ_0114427 is upregulated in serum specimens from septic AKI patients and LPS-induced HK-2 cells. LPS treatment suppresses cell viability and promotes apoptosis and inflammation in HK-2 cells. Circ_0114427 knockdown ameliorates the effects of LPS on cell viability, apoptosis and inflammation in HK-2 cells. Circ_0114427 regulates LPS-induced HK-2 cell injury by regulating miR-495-3p/TRAF6/NF-ÎșB/p65 axis
Effect of pre-homogenizing treatment on microstructure and mechanical properties of hot-rolled AZ91 magnesium alloys
To improve the homogeneity and rolling formability of as-cast AZ91 magnesium, the effects of pre-homogenizing treatment on microstructure evolution, deformation mechanism, mechanical properties and tensile fracture morphology of hot-rolled AZ91 magnesium alloy were studied. The results showed that the amount of coarse ÎČ-Mg17Al12 phase decreases dramatically, being distributed along the grain boundaries as small strips after homogenizing. Twining plays a dominant role in the deformation mechanism of AZ91 alloys in the experimental condition, while dynamic recrystallization (DRX) considerably occurred in homogenized-rolled alloys, contributed to microstructure uniformity and ÎČ-Mg17Al12 phase precipitated refinement. The tensile strength of homogenized-rolled AZ91 alloys increases dramatically with elongation declining slightly in contrast to homogenized alloys. The fracture surface of homogenized-rolled specimen exhibits more ductile fracture with the manifestation of a large amount of dimples distributing higher density in matrix, while the micro cracks are prone to initiate around the Mg/Mg17Al12 phase interface and grain boundaries owing to the fragile interface bonding of two phases
Imidazolium Ionic Liquid Modified Graphene Oxide: As a Reinforcing Filler and Catalyst in Epoxy Resin
Surface modification of graphene oxide (GO) is one of the most important issues to produce high performance GO/epoxy composites. In this paper, the imidazole ionic liquid (IMD-Si) was introduced onto the surface of GO sheets by a cheap and simple method, to prepare a reinforcing filler, as well as a catalyst in epoxy resin. The interlayer spacing of GO sheets was obviously increased by the intercalation of IMD-Si, which strongly facilitated the dispersibility of graphene oxide in organic solvents and epoxy matrix. The addition of 0.4 wt % imidazolium ionic liquid modified graphene oxide (IMD-Si@GO), yielded a 12% increase in flexural strength (141.3 MPa), a 26% increase in flexural modulus (4.69 GPa), and a 52% increase in impact strength (18.7 kJ/m2), compared to the neat epoxy. Additionally the IMD-Si@GO sheets could catalyze the curing reaction of epoxy resin-anhydride system significantly. Moreover, the improved thermal conductivities and thermal stabilities of epoxy composites filled with IMD-Si@GO were also demonstrated
Effect of SiC Nanoparticles on Hot Deformation Behavior and Processing Maps of Magnesium Alloy AZ91
The hot deformation behavior and processing characteristics of AZ91 alloy and nano-SiCp/AZ91 composite were compared at temperature ranges of 523 Kâ673 K and strain rates of 0.001â1 sâ1. Positive impact of SiC nanoparticles on pinning grain boundaries and inhibiting grain growth was not obvious when deformation temperature was below 623 K, but was remarkable when the temperature was above 623 K. By comparing compressive stress-strain curves of AZ91 alloy and nano-SiCp/AZ91 composites, the addition of nanoparticles could improve the deformation ability of a matrix alloy under high-temperature conditions. There was no essential difference of deformation mechanism between AZ91 alloy and the composite, but hot deformation activation energy of the composite was significantly lower than that of the AZ91 alloy. The AZ91 alloy and the composite had the same workability region of 600 Kâ673 K and 0.001â1 sâ1, while instability region for the composite was reduced compared with that of AZ91 alloy at high temperature
Characterization of a Secretory YML079-like Cupin Protein That Contributes to <i>Sclerotinia sclerotiorum</i> Pathogenicity
Sclerotinia sclerotiorum causes devastating diseases in many agriculturally important crops, including oilseed rape and sunflower. However, the mechanisms of Sclerotinia sclerotiorum pathogenesis remain poorly understood. In this study, we characterized a YML079-like cupin protein (SsYCP1) from Sclerotinia sclerotiorum. We showed that SsYCP1 is strongly expressed and secreted during Sclerotinia sclerotiorum infection. Sclerotinia sclerotiorum infection was promoted by SsYCP1 overexpression and inhibited by silencing this gene with synthetic double-stranded RNA. These results collectively indicate SsYCP1 as a putative effector protein that contributes to Sclerotinia sclerotiorum pathogenicity. These findings extend our understanding of effector-mediated Sclerotinia sclerotiorum pathogenesis and suggest a novel role for YML079-like cupin proteins in plantâpathogen interactions
Effect of SiC nanoparticles addition on the microstructures and mechanical properties of ECAPed Mg9Alâ1Si alloy
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