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Abstract In the field of recommendation system, the memory-based Collaborative filtering has been proven to be useful in lots of practices. Similarity measures like Pearson correlation coefficient tend to only focus on improving as much as possible the accuracy. Handling datasets with different features, exiting measures cannot apply to different types of data simultaneously. In this paper, an improved similarity measure Common Pearson Correlation Coefficient (COPC) was proposed. Unlike existing measures, it strongly depends on chosen distance function, which adhere to the natural property of monotonicity and utilize consensus evaluation measure to capture an optimal value to improve PCC measure. To mitigate sparse problem, we also introduce the Hellinger Distance (Hg) as global similarity to lower the impact of lacking co-rated items. Experimental results on real-world datasets demonstrates that our measure outperformed the existing schemes of predicting ratings. [ABSTRACT FROM AUTHOR]

So far, few data are available on the reproductive toxicological assessment of β-diketone antibiotics (DKAs), a class of ubiquitous pseudo-persistent pollutant, in zebrafish ( Danio rerio ). Herein, we reported the reproductive effects of DKAs by means of transcriptome analysis (F1-zebrafish), changes in a series of reproductive indices (F0-zebrafish) and histopathological observations. A total of 1170, 983 and 1399 genes were found to be differentially expressed when compared control vs. 6.25 mg/L, control vs. 12.5 mg/L and 6.25 vs. 12.5 mg/L DKA-exposure treatments, respectively. Among three comparison groups, 670, 569 and 821 genes were respectively assigned for GO analyses based on matches with sequences of known functions. In 149 KEGG-noted metabolic pathways, the preferential one was the MAPK (mitogen-activated protein kinase) signaling pathway, followed by oxidative phosphorylation, neuroactive ligand-receptor interaction and so on. By qPCR verification, 6 genes ( c6ast4, igfbp1b, mrpl42, tnnc2, emc4 and ddit4 ) showed consistent gene expression with those identified by transcriptome sequencing. Due to DKA-exposure, the concentrations of plasma estradiol and testosterone, and the gonado-somatic index were significantly dose-dependently declined. Also, DKA-exposure led to declining in zebrafish reproductive capacity, reflecting in fertilization, hatchability and egg production. Histopathological observations demonstrated that zebrafish ovary and testis suffered serious damage after DKA-exposure. The 4-oxo-TEMP signals increased obviously with increasing DKA-exposed concentrations, implying disruption of balance between generation and clearance of 1 O 2 . In summary, DKAs not only produce reproductive toxicological effects on F0-zebrafish, but also result in adverse consequences for growth and development of F1-zebrafish. [ABSTRACT FROM AUTHOR]

Microplastics and antibiotics widely coexist in the aquatic environment, especially in mariculture regions. However, antibiotics adsorbed on microplastics and their role in the colonization of microorganisms on microplastics are poorly understood. Therefore, in-situ aging experiments were conducted to investigate the impact of antibiotics and microplastics co-occurrence on microorganisms and assess their potential risks to human health. Results showed that antibiotics were adsorbed selectively on microplastics, with 29 investigated antibiotics (n = 40) detected in surrounding water but only 6 investigated antibiotics were adsorbed on microplastics. The concentration of antibiotics accumulated on microplastics was controlled by microplastic types and environmental conditions. For example, aged polypropylene (PP) had more developed pore structures resulting in higher adsorption of antibiotics than other microplastic types. High-throughput sequencing showed higher diversity and distinct composition of microorganisms attached to the microplastics than the surrounding water. Opportunistic pathogenic bacteria such as Mycobacterium possessed positive relationships with tetracycline and doxycycline on aged microplastics, which showed adsorbed antibiotics on aged microplastics could benefit some specific pathogens colonized on the microplastics and spread into unaffected ecosystems, marine organisms even humans. The health risk quotient (HQ) implied the potential human health risk of consuming commercial seafood polluted by antibiotics and microplastic loaded with antibiotics. This study revealed the interaction of antibiotics and microorganisms with aged microplastics in aquaculture systems, providing a novel insight into their synergistic effects on ecological and human health. [Display omitted] • Aging under environmentally realistic conditions reveals the adsorption of microplastics. • Microplastic types and environmental conditions influence the antibiotics adsorption of microplastics. • Antibiotics adsorbed on aged microplastics benefit the colonization of Mycobacterium and Pseudomonas on microplastics. • The coexisting of antibiotics and microplastics aggravates the potential human health risk of ingesting commercial seafood. [ABSTRACT FROM AUTHOR]

Benzo[a]pyrene (BaP), a widely existed polycyclic aromatic hydrocarbon pollutant in aquatic environment, has toxic effects on marine animals and their generations, but the intergenerational immunotoxic mechanism underlying has not been clearly understood. In the study, the offspring of marine medaka (oryzias melastigma) which were exposed to 0.5 μg L−1 BaP suffered from circadian rhythm oscillation disorders and severe DNA damage. Many clock-associated genes like per1 were significantly modulated in offspring, both per1 and p53 were significantly inhibited that altered the progression of cell cycle and inhibited DNA repair, which possibly resulted in the increased mortality of offspring. The hypermethylation of the per1 promotor and abnormal levels of N6-methyladenosine (m6A) suggested that the underlying mechanism was probably related to the epigenetic modification. Moreover, the offspring from paternal BaP exposure had more severe DNA damage and a higher degree of hypermethylation than those from maternal exposure. F1 larvae from BaP-exposed parents were more sensitive to BaP exposure, showing that the expression of immune and metabolism-related genes were significantly up-regulated. Taken together, the parental toxicity induced by BaP could be passed to F1 generation and the mechanism underlying was probably associated with a characteristic circadian rhythm disorder. Image 1 • Parental BaP exposure induced circadian rhythm disorder in offspring. • Parental BaP exposure caused immune disorder in offspring through per1 and p53. • The possible mechanism was related to per1 promotor methylation and RNA methylation. • The offspring from BaP exposed males suffered more serious effects. • F1 larvae from BaP exposed parents were more sensitive to BaP. The parental toxicity induced by BaP could be passed to F1 generation and the underlying mechanism was probably associated with circadian rhythm disorder. [ABSTRACT FROM AUTHOR]

• The interactions between resveratrol and gut microbiota on hepatic steatosis are investigated. • The fecal microbiota transplantation is used to investigate the interactions. • Resveratrol can reverse high-fat-diet induced dysbiosis. • Resveratrol can ameliorate the hepatic steatosis by regulating gut microbiota. To investigate whether resveratrol could ameliorate the hepatic steatosis in high-fat diet (HFD) fed mice by modulating gut microbiota composition, fecal microbiota transplantation (FMT) was utilized in this study. Our results showed that resveratrol significantly ameliorated hepatic steatosis in HFD mice, increased the gene expression of fasting-induced adipose factor, and decreased the expression of lipogenesis-related genes and proteins (SREBP-1, FAS and ACC). In addition, resveratrol reversed HFD-induced gut microbiota dysbiosis, with an increase in the relative abundance of Bacteroidetes and a decrease in that of Firmicutes and Proteobacteria. Subsequent results showed the gut microbiota compositions of FMT recipient groups were similar to those of corresponding donor groups. And the changes of state of hepatic steatosis and expression of SREBP-1, ACC and FAS were coordinated with the results of gut microbiota. In conclusion, these results provided evidence to support the resveratrol could ameliorate the hepatic steatosis by modulating the gut microbiota. [ABSTRACT FROM AUTHOR]