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• High accuracy and good generalization ability. • Easy saturation and unable to perceive continuous variation of parameters are solved. • The relationship between the specklegram and the accuracy is analyzed. • Analytical process is conductive to the selection of dataset. • Transfer learning is used to tackle the poor portability and reusability. A novel fiber specklegram torsion sensor based on multimode fiber (MMF) is proposed and experimentally demonstrated in this paper. The Residual Network (ResNet) is used to establish the relationship between the changing process of the specklegram and the torsion angle of the MMF. The experimental results indicate that the sensor exhibits the advantages of high accuracy and large measurement range. Within a torsion angle range of 0–360°, the prediction error is within ±2° for 99.1% of the specklegrams in test set. By analyzing the decorrelation process of the specklegrams from different kinds of MMFs, we find that the difference in torsion angle prediction accuracy of different MMFs stems from the decorrelation angle of the specklegram, and the larger decorrelation angle of specklegram holds higher torsion angle sensing accuracy of the trained ResNet. Meanwhile, the difference of the decorrelation angle of specklegram is attributed to the difference of the fiber normalized frequency. This analytical process may be applicable to the analysis of other specklegram based sensing schemes and the selection of dataset for fiber specklegram sensor. The possibility of transfer learning is also investigated to show an improved portability and reusability. In addition, the fiber specklegram torsion sensor owns other merits such as easy fabrication and good robustness, which shows its wide range of potential applications. [ABSTRACT FROM AUTHOR]

Di-n-butyl phthalates (DBP) are recognized as ubiquitous contaminants in soil and adversely impact the health of organisms. The effect of DBP on the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT), malondialdehyde (MDA) content and DNA damage were used as biomarkers to analyze the relationship between DNA damage and oxidative stress and to evaluate the genotoxic effect of DBP on earthworms ( Eisenia fetida ). DBP was added to artificial soil in the amounts of 0, 5, 10, 50 and 100 mg per kg of soil. Earthworm tissues exposed to each treatment were collected on the 7th, 14th, 21st, and 28th day of the treatment. The results showed that SOD and CAT levels were significantly inhibited in the 100 mg kg −1 treatment group on day 28. MDA content in treatment groups was higher than in the control group throughout the exposure time, suggesting that DBP may lead to oxidative stress in cells. A dose–response relationship existed between DNA damage and total soil DBP levels. The comet assay showed that increasing concentrations of DBP resulted in a gradual increase in the OTM, Comet Tail Length and Tail DNA %. The degree of DNA damage was increased with increasing concentration of DBP. These results suggested that DBP induced serious oxidative damage on earthworms and induced the formation of reactive oxygen species (ROS) in earthworms. The excessive generation of ROS caused damage to vital macromolecules including lipids and DNA. DBP in the soils were responsible for the exerting genotoxic effects on earthworms. [ABSTRACT FROM AUTHOR]

As a flame retardant, triphenyl phosphate (TPHP) is commonly added to various daily products. Due to its easy diffusion, TPHP pollution has become a global concern. Despite the wide focus on environmental risk, the sub-chronic ecotoxicity of TPHP in soil organisms remains unclear. In this study, the artificial soil exposure method was used to analyze the oxidative stress and DNA damage in earthworms with 0, 20, 40, 60 and 80 mg/kg TPHP treatments through the response of reactive oxygen species (ROS), antioxidant and detoxifying enzymes, malondialdehyde (MDA) and olive tail moment (OTM) at 7, 14, 21 and 28 days. Throughout the experimental period, the results showed that the ROS content in earthworms treated with 20, 40, 60 and 80 mg/kg TPHP treatments increased by 9.43–18.37 %, 6.07–25.73 %, 7.71–42.61 % and 8.22–46.70 %, respectively, compared to the control treatment. Meanwhile, the activities of antioxidant and detoxification enzymes in earthworms with all TPHP treatments were significantly activated after exposure for 7 and 14 days, and then inhibited at 21 and 28 days. Despite the protection of antioxidant enzymes and detoxification enzymes, MDA content in earthworms with the 20 mg/kg treatment still significantly increased at 7 and 14 days of exposure, as well as in the other three treatments. Compared to the control treatment, the obviously higher OTM values in earthworms with TPHP treatments possibly indicated a genotoxicity of TPHP in earthworms. Furthermore, the integrated biomarker response index (IBRv2) revealed that earthworms showed an obvious biochemical response TPHP-contaminated soil, which was strongly correlated with TPHP concentrations and exposure time. This study provides insights into the TPHP hazard in the soil environment and offers a reference to assess its environmental risk to soil ecosystems. [Display omitted] • Triphenyl phosphate exposure induced oxidative stress in earthworms. • Triphenyl phosphate induced ROS accumulation overrode the elimination of defend systems in earthworms. • Triphenyl phosphate exposure caused seriously oxidative damage and DNA damage in earthworms • IBRv2 showed the effects of triphenyl phosphate on earthworm were closely related to its exposure does and time. [ABSTRACT FROM AUTHOR]

S. M. Ward, A. P. Gadbut, D. Tang, A. G. Papageorge, L. Wu, G. LI, J. V. Barnett and J. B. Galper. TGFβ Regulates the Expression of Gαi2 via an Effect on the Localization of Ras. Journal of Molecular and Cellular Cardiology (2002) 34, 1217–1226. The negative chronotropic response of the heart to parasympathetic stimulation is mediated via the interaction of M2 muscarinic receptors, Gαi2 and the G-protein coupled inward rectifying K+ channel, GIRK1. Here TGFβ1 is shown to decrease the expression of Gαi2 in cultured chick atrial cells in parallel with attenuation of the negative chronotropic response to parasympathetic stimulation. The response to the acetylcholine analogue, carbamylcholine, decreased from a 95±2% (±SEM, n=8) inhibition of beat rate in control cells to 18±2% (±SEM,n =8) in TGFβ1 treated cells. Data support the conclusion that TGFβ regulation of Gαi2 expression was mediated via an effect on Ras. TGFβ1 inhibited Gαi2 promoter activity by 56±6% (±SEM, n=4) compared to control. A dominant activating Ras mutant reversed the effect of TGFβ on Gαi2 expression and stimulated Gαi2 promoter activity 1.7 fold above control. A dominant negative Ras mutant mimicked the effect of TGFβ1 on Gαi2 promoter activity. TGFβ had no effect on the ratio of GDP/GTP bound Ras, but markedly decreased the level of membrane associated Ras and increased the level of cytoplasmic Ras compared to control. Furthermore, farnesol, a precursor to farnesylpyrophosphate, the substrate for the farnesylation of Ras, not only reversed TGFβ1 inhibition of Ras localization to the membrane, but also reversed TGFβ1 inhibition of Gαi2promoter activity. FTI-277, a specific inhibitor of the farnesylation of Ras, mimicked the effect of TGFβ1 on Ras localization and Gαi2 promoter activity. These data suggest a novel relationship between TGFβ signaling, regulation of Ras function and the autonomic response of the heart. [Copyright &y& Elsevier]