Internal Defects Detection Method of the Railway Track Based on Generalization Features Cluster Under Ultrasonic Images

There may be several internal defects in railway track work that have different shapes and distribution rules,and these defects affect the safety of high-speed trains.Establishing reliable detection models and methods for these internal defects remains a challenging task.To address this challenge,in this study,an intelligent detection method based on a generalization feature cluster is proposed for internal defects of railway tracks.First,the defects are classified and counted according to their shape and location features.Then,generalized features of the internal defects are extracted and formulated based on the maximum difference between different types of defects and the maximum tolerance among same defects’types.Finally,the extracted generalized features are expressed by function constraints,and formulated as generalization feature clusters to classify and identify internal defects in the railway track.Furthermore,to improve the detection reliability and speed,a reduced-dimension method of the generalization feature clusters is presented in this paper.Based on this reduced-dimension feature and strongly constrained generalized features,the K-means clustering algorithm is developed for defect clustering,and good clustering results are achieved.Regarding the defects in the rail head region,the clustering accuracy is over 95%,and the Davies-Bouldin index(DBI)index is negligible,which indicates the validation of the proposed generalization features with strong constraints.Experimental results prove that the accuracy of the proposed method based on generalization feature clusters is up to 97.55%,and the average detection time is 0.12 s/frame,which indicates that it performs well in adaptability,high accuracy,and detection speed under complex working environments.The proposed algorithm can effectively detect internal defects in railway tracks using an established generalization feature cluster model.

Groundwater chromate removal by autotrophic sulfur disproportionation

Chromate[Cr(VI)]contamination in groundwater is a global environmental challenge.Traditional elemental sulfur-based biotechnologies for Cr(VI)removal depend heavily on the synthesis of dissolved organic carbon to fuel heterotrophic Cr(VI)reduction,a bottleneck in the remediation process.Here we show an alternative approach by leveraging sulfur-disproportionating bacteria(SDB)inherent to groundwater ecosystems,offering a novel and efficient Cr(VI)removal strategy.We implemented SDB within a sulfur-packed bed reactor for treating Cr(VI)-contaminated groundwater,achieving a notable removal rate of 6.19 mg L^(-1) h^(-1) under oligotrophic conditions.We identified the chemical reduction of Cr(VI)via sulfide,produced through sulfur disproportionation,as a key mechanism,alongside microbial Cr(VI)reduction within the sulfur-based biosystem.Genome-centric metagenomic analysis revealed a symbiotic relationship among SDB,sulfur-oxidizing,and chromate-reducing bacteria within the reactor,suggesting that Cr(VI)detoxification by these microbial communities enhances the sulfurdisproportionation process.This research highlights the significance of sulfur disproportionation in the cryptic sulfur cycle in Cr(VI)-contaminated groundwater and proposes its practical application in groundwater remediation efforts.

Deletion of heterogeneous nuclear ribonucleoprotein K in satellite cells leads to inhibited skeletal muscle regeneration in mice

Heterogeneous nuclear ribonucleoprotein K(hnRNPK)is a predominantly nuclear RNA-binding protein that can bind to DNA or RNA through three KH domains and interact with multiple proteins by interactive region.These binding activities enable hnRNPK to link the function in a wide array of diverse cellular processes,such as chromatin remodeling,gene transcription,RNA metabolism,protein translation,DNA repair,and cell signal transduction,thereby playing crucial roles in many biological processes,including development,axonal regeneration,spermatogenesis,cell cycle,apoptosis,differentiation,and carcinogenesis.

Metabolomic profiles in a green alga (Raphidocelis subcapitata) following erythromycin treatment: ABC transporters and energy metabolism

A recent study showed that erythromycin(ERY)exposure caused hormesis in a model alga(Raphidocelis subcapitata)where the growth was promoted at an environmentally realistic concentration(4μg/L)but inhibited at two higher concentrations(80 and 120μg/L),associated with opposite actions of certain signaling pathways(e.g.,xenobiotic metabolism,DNA replication).However,these transcriptional alterations remain to be investigated and verified at the metabolomic level.This study uncovered metabolomic profiles and detailed toxic mechanisms of ERY in R.subcapitata using untargetedmetabolomics.Themetabolomic analysis showed that metabolomic pathways including ABC transporters,fatty acid biosynthesis and purine metabolism were associated with growth promotion in algae treated with 4μg/L ERY.An overcompensation was possibly activated by the low level of ERY in algae where more resources were reallocated to efficiently restore the temporary impairments,ultimately leading to the outperformance of growth.By contrast,algal growth inhibition in the 80 and 120μg/L ERY treatments was likely attributed to the dysfunction of metabolomic pathways related to ABC transporters,energy metabolism and metabolism of nucleosides.Apart from binding of ERY to the 50S subunit of ribosomes to inhibit protein translation as in bacteria,the data presented here indicate that inhibition of protein translation and growth performance of algae by ERY may also result from the suppression of amino acid biosynthesis and aminoacyl-tRNA biosynthesis.This study provides novel insights into the dose-dependent toxicity of ERY on R.subcapitata.

Triclosan toxicity in a model cyanobacterium (Anabaena flos-aquae): Growth, photosynthesis and transcriptomic response

Exposure to triclosan(TCS)has been reported to reduce photosynthetic pigments,suppress photosynthesis,and inhibit growth in both prokaryotic and eukaryotic algae including Anabaena flos-aquae(a model cyanobacterium).In particular,cyanobacteria are more sensitive to TCS toxicity compared to eukaryotic algae possibly due to the structural similarity to bacteria(target organisms);however,whether TCS exerts its toxicity to cyanobacteria by targeting signaling pathways of fatty acid biosynthesis as in bacteria remains virtually unknown,particularly at environmental exposure levels.With the complete genome sequence of A.flos-aquae presented in this study,the transcriptomic alterations and potential toxic mechanisms in A.flos-aquae under TCS stress were revealed.The growth,pigments and photosynthetic activity of A.flos-aquae were markedly suppressed following a 7-day TCS exposure at 0.5μg/L but not 0.1μg/L(both concentrations applied are environmentally relevant).The transcriptomic sequencing analysis showed that signaling pathways,such as biofilm formation–Pseudomonas aeruginosa,two-component system,starch and sucrose metabolism,and photosynthesis were closely related to the TCS-induced growth inhibition in the 0.5μg/L TCS treatment.Photosynthesis systems and potentially two-component system were identified to be sensitive targets of TCS toxicity in A.flos-aquae.The present study provides novel insights on TCS toxicity at the transcriptomic level in A.flos-aquae.

Transcriptional response of a green alga(Raphidocelis subcapitata) exposed to triclosan:photosynthetic systems and DNA repair

Recent studies show that triclosan(TCS)exposure causes reduction in pigments,suppression of photosynthesis,and induction of oxidative stress at the physiological level,resulting in morphological alteration and growth inhibition in algae including Raphidocelis subcapitata(R.subcapitata,a freshwater model green alga).However,the underlying molecular mechanisms remain to be elucidated,especially at environmentally relevant concentrations.The present study uncovered the transcriptional profiles and molecular mechanisms of TCS toxicity in R.subcapitata using next-generation sequencing.The algal growth was drastically inhibited following a 7-day exposure at both 75 and 100μg/L TCS,but not at 5μg/L(environmentally realistic level).The transcriptomic analysis shows that molecular signaling pathways including porphyrin and chlorophyll metabolism,photosynthesis–antenna proteins,and photosynthesis were suppressed in all three TCS treatments,and the perturbations of these signaling pathways were exacerbated with increased TCS exposure concentrations.Additionally,signaling of replication-coupled DNA repair was only activated in 100μg/L TCS treatment.These results indicate that photosynthesis systems were sensitive targets of TCS toxicity in R.subcapitata,which is distinct from the inhibition of lipid synthesis by TCS in bacteria.This study provides novel knowledge on molecular mechanisms of TCS toxicity in R.subcapitata.