Single nucleotide polymorphisms (SNPs) in 7000 bp of the mitochondrial genome, encompassing 15 coding regions from COI to ND5, were characterized by single strand polymorphism analysis and confirmed by DNA sequencing. About 2.4% of normozoospermic men and 8.4% of men with poor semen quality had at least one nucleotide substitution. Most of the substitutions occurred in the third codon and did not change the amino acid. Hydrophobicity plots of the proteins with changes in an amino acid as a result of a nucleotide substitution suggested that they did not affect the function of the protein. The two most common substitutions at nucleotide (nt) 9055 and 11719 had significantly higher frequencies in men with reduced sperm motility. Eleven percent of the men with poor semen parameters and 1.3% of normozoospermic men had a 9055 substitution, 12% of the men with poor semen parameters had a substitution at nt 11719, but none of the normozoospermic men had this substitution. All the patients with these substitutions had reduced sperm motility and/or low sperm count. These SNPs in the mitochondrial genome were in a homoplasmic state. Thus, we propose that possessing these mitochondrial mutations compromises the semen quality of these men.

With multi-wall carbon nanotubes (MWNTs) as reinforcement, a 12 vol% MWNTs/alumina (Al 2 O 3 ) ceramic composite was obtained by hot pressing. A fracture toughness of 5.5570.26 MPa . m 1/2 , 1.8 times that of pure Al 2 O 3 ceramics, was achieved. Experimental results showed that the enveloping of carbon nanotubes (CNTs) with sodium dodecyl sulfate (SDS) is effective in changing the hydrophobicity of CNTs to hydrophilicity and improving the dispersion of CNTs in aqueous solution. Enveloped with SDS, CNTs can be homogeneously mixed with Al 2 O 3 at a microscopic level by heterocoagulation. This mixing method can obviously improve the chemical compatibility between CNTs and Al 2 O 3 , which is important for enhancement of interfacial strength between them. J ournal

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A highly selective and sensitive indirect competitive enzyme-linked immunosorbent assay (ELISA) for Sudan I was developed. Two hapten derivatives with different lengths of carboxylic spacer at the azo-bound para-position were synthesized and coupled to carrier proteins. The hapten-bovine serum albumin (BSA) conjugates were used as immunogens, while the hapten-ovalbumin (OA) conjugates were applied as coating antigens. The antisera which were obtained from four immunized rabbits were characterized in terms of sensitivity and specificity. At optimal experimental conditions it was found that IC50 and LOD values of seven pairs based on four antisera and two coating antigens were in the range of 0.3-2 ng/mL and 0.02-0.1 ng/mL, respectively. The most sensitive ELISA could be established with Sudan I-propionic acid-OA coating antigen and the antiserum which was obtained with the corresponding immunogen. The cross-reactivity values of the four antisera with Sudan II, III, and IV was estimated with 0.1-14.3%. No cross-reactivity was found with six edible colorants Sunset yellow, Amarant, Kermes, Indigotin, Bright blue and Lemon yellow, indicating high specificity for Sudan I. Six food samples were fortified with Sudan I and extracted by simple sample preparation. The methanolic extracts after dilution with methanol:water (5:95, v/v) were analyzed by the developed ELISA. Assay precision and accuracy was estimated by determination of three replicates. Acceptable recovery rates of 92.5-114% and intra-assay coefficients of variation of 5.9-24.8% were obtained. The data were validated by conventional HPLC method. As revealed, both methods were highly correlated (r = 0.9851, n = 7), demonstrating the applicability of the developed ELISA for Sudan I analysis in food samples.

Microplastics (MPs) pollution is a global paradigm that raises concern in relation to environment and human health. In order to investigate the molecular toxicity mechanisms of MPs, transcriptomic analyses were performed on in vitro Caco‐2 cell model. After observing that polystyrene microplastics (PS‐MPs) decreased cell viability in a dose‐dependent manner, the responsible genes and involved pathways that might make contribution to PS‐MBs‐induced toxicity to Caco‐2 cells were identified with Illumina RNA seq. A total of 442 genes including, 210 up‐regulated ones and 232 down‐regulated ones, showed differential expression after treatment by PS‐MPs with a concentration of 12.5 mg L−1 or 50.0 mg L−1 for 24 hours. Gene Ontology (GO) annotation enriched unigenes can be grouped into three separated clusters: cellular component (CC), biological process (BP), and molecular function (MF). The dominate pathways related to NF‐κB, MAPK signaling, cytokine‐cytokine receptor interaction, and toll‐like receptor were strongly influenced by PS‐MBs. These pathways are involved in modulating cell inflammatory and proliferation. The qPCR were applied to investigate the transcriptional level of five proliferation related genes (Ras, ERK, MER, CDK4, Cyclin D1) and four inflammation related genes (TRPV1, iNOS, IL‐1β, IL‐8), and the results were consistent with RNA‐seq data. This study has provided new insight into the understanding of the toxicity effects of PS‐MBs‐induced intestinal inflammatory diseases.

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In this paper, magnetic iron fibres of diameter down to 2 µm were produced by using the bundle-drawing method, and iron fibre-epoxy resin composites were prepared by mixing epoxy resin with the iron fibres. The electromagnetic parameters of the iron fibre-epoxy resin composites were measured using the transmission/reflection coaxial line method at microwave frequencies. The measured results show that the iron fibre-epoxy resin composites exhibit larger values of µ and µ in the frequency range of 2-18 GHz, and the values of both ε and ε steeply increase with increase in the fibre concentration. Based on a theoretical calculation of the reflection coefficient, the microwave absorbing properties of the iron fibre-epoxy resin composites were examined. The calculated results indicate that the iron fibre-epoxy resin composites exhibit good absorption performance in the radar band. The optimum absorption can be achieved by optimizing the fibre concentration. The absorption peak frequency can be manipulated easily by changing the thickness of the material layer. The calculated results also indicate that magnetic iron fibres may be useful in producing thin and lightweight radar absorbing materials.

Several different mixture equations have previously been used to characterize the microwave properties of the ferrite particle-insulating medium mixtures. For very low particle concentrations, these equations give nearly the same results. But when the particle concentration is higher than a few per cent, these equations generally give different results. Based on microwave measurements and numerical calculations, the validity of five well-known mixture equations has been examined in this paper. The experimental results show that both the Bruggeman and QCA-CP ('quasi-crystalline approximation with coherent potential') equations can accurately describe the microwave properties of the ferrite-medium mixtures, and that the Lichtenecker, Logarithm and Maxwell-Garnett equations are not suitable for characterizing the ferrite-medium mixtures over a wide particle concentration range at microwave frequencies. The microwave intrinsic permeability and permittivity spectra of some BaZn 2−x Co x Fe 16 O 27 , Ba 4 Zn 2−x Co x Fe 36 O 60 and Ba 2 Zn 2−x Co x Fe 12 O 22 ferrite particles have been presented, which were calculated from the measurement data of the ferrite-wax mixtures using the Bruggeman equation. The microwave properties of these ferrite particles have also been discussed. In the 1-6 GHz range, both the real and imaginary parts of permeability of BaZn 2−x Co x Fe 16 O 27 and Ba 4 Zn 2−x Co x Fe 36 O 60 ferrite particles evidently increase with the increasing Co concentration. Both the real and imaginary parts of permittivity of Ba 2 Zn 2−x Co x Fe 12 O 22 ferrite particles apparently decrease as the Co concentration increases.