Rain streaks removal is an important issue in outdoor vision systems and has recently been investigated extensively. In this paper, we propose a novel video rain streak removal approach FastDeRain, ...which fully considers the discriminative characteristics of rain streaks and the clean video in the gradient domain. Specifically, on the one hand, rain streaks are sparse and smooth along the direction of the raindrops, whereas on the other hand, clean videos exhibit piecewise smoothness along the rain-perpendicular direction and continuity along the temporal direction. Theses smoothness and continuity result in the sparse distribution in the different directional gradient domain. Thus, we minimize: 1) the 4 norm to enhance the sparsity of the underlying rain streaks; 2) two l1 norm of unidirectional total variation regularizers to guarantee the anisotropic spatial smoothness; and 3) an 4 norm of the time-directional difference operator to characterize the temporal continuity. A split augmented Lagrangian shrinkage algorithm-based algorithm is designed to solve the proposed minimization model. Experiments conducted on synthetic and real data demonstrate the effectiveness and efficiency of the proposed method. According to the comprehensive quantitative performance measures, our approach outperforms other state-of-the-art methods, especially on account of the running time. The code of FastDeRain can be downloaded at https://github.com/TaiXiangJiang/FastDeRain.
Hyperspectral unmixing has attracted much attention in recent years. Single sparse unmixing assumes that a pixel in a hyperspectral image consists of a relatively small number of spectral signatures ...from large, ever-growing, and available spectral libraries. Joint-sparsity (or row-sparsity) model typically enforces all pixels in a neighborhood to share the same set of spectral signatures. The two sparse models are widely used in the literature. In this paper, we propose a joint-sparsity-blocks model for abundance estimation problem. Namely, the abundance matrix of size <inline-formula> <tex-math notation="LaTeX">m\times n </tex-math></inline-formula> is partitioned to have one row block and <inline-formula> <tex-math notation="LaTeX">s </tex-math></inline-formula> column blocks and each column block itself is joint-sparse. It generalizes both the single (i.e., <inline-formula> <tex-math notation="LaTeX">s=n </tex-math></inline-formula>) and the joint (i.e., <inline-formula> <tex-math notation="LaTeX">s=1 </tex-math></inline-formula>) sparsities. Moreover, concatenating the proposed joint-sparsity-blocks structure and low rankness assumption on the abundance coefficients, we develop a new algorithm called joint-sparse-blocks and low-rank unmixing . In particular, for the joint-sparse-blocks regression problem, we develop a two-level reweighting strategy to enhance the sparsity along the rows within each block. Simulated and real-data experiments demonstrate the effectiveness of the proposed algorithm.
Antibiotics are widely used in humans and animals, but there is a big concern about their negative impacts on ecosystem and human health after use. So far there is a lack of information on emission ...inventory and environmental fate of antibiotics in China. We studied national consumption, emissions, and multimedia fate of 36 frequently detected antibiotics in China by market survey, data analysis, and level III fugacity modeling tools. Based on our survey, the total usage for the 36 chemicals was 92700 tons in 2013, an estimated 54000 tons of the antibiotics was excreted by human and animals, and eventually 53800 tons of them entered into the receiving environment following various wastewater treatments. The fugacity model successfully predicted environmental concentrations (PECs) in all 58 river basins of China, which are comparable to the reported measured environmental concentrations (MECs) available in some basins. The bacterial resistance rates in the hospitals and aquatic environments were found to be related to the PECs and antibiotic usages, especially for those antibiotics used in the most recent period. This is the first comprehensive study which demonstrates an alarming usage and emission of various antibiotics in China.
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•Microalgae-based technology is a promising alternative for antibiotics removal.•The underlying mechanisms of microalgae-based antibiotics removal are summarized.•Several novel ...approaches and hybrid techniques are recommended to promote antibiotics removal.•This review also outlines future research directions of microalgae-based technology.
Antibiotics contamination is an emerging environmental concern, owing to its potential risks to ecosystems and human health. Microalgae-based technology has been widely reported as a promising alternative to conventional wastewater treatment, since it is a solar-power driven, ecologically friendly, cost-effective, and sustainable reclamation strategy. This review provides fundamental insights into the major mechanisms underpinning microalgae-based antibiotics removal, including bioadsorption, bioaccumulation, and biodegradation. The critical role of extracellular polymeric substances on bioadsorption and extracellular biodegradation of antibiotics are also covered. Moreover, this review sheds light on the important factors affecting the removal of antibiotics by microalgae, and summarizes several novel approaches to improve the removal efficiency, including acclimation, co-metabolism and microbial consortium. Besides, hybrid systems (such as, microalgae-based technologies combined with the conventional activated sludge, advanced oxidation processes, constructed wetlands, and microbial fuel cells), and genetic engineering are also recommended, which will be feasible for enhanced removal of antibiotics. Finally, this review also highlights the need for further studies aimed at optimizing microalgae-based technology, with emphasis on improving performance and expanding its application in large-scale settings, especially in terms of technical, environmental-friendly and economically competitiveness. Overall, this review summarizes current understanding on microalgae-based technologies for removal of antibiotics and outlines future research directions.
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•We investigated antibiotic resistome during manure composting by metagenomics.•Moisture was the key environmental factor over composting.•Composting significantly reduced the ...relative abundance of ARGs and MGEs.•Actinobacteria was the primary potential host of ARGs over composting.•Bacterial community and BMRGs profiles structured the antibiotic resistome.
Composting has been widely used to turn livestock manure into organic fertilizer. However, livestock manure contains various contaminants including antibiotics and antibiotic resistance genes (ARGs). Here we investigated the variation of antibiotic resistome and its influencing factors during a commercial livestock manure composting. The results showed that composting could effectively reduce the relative abundance of ARGs and mobile genic elements (MGEs). As the dominant phylum in the composting samples, the key potential bacterial host of ARGs were Actinobacteria such as Leucobacter, Mycobacterium and Thermomonosporaceae unclassified. Meanwhile, Legionella pneumophila, Staphylococcus saprophyticus, Haemophilus ducreyi and Siccibacter turicensis may be the key potential pathogenic host of ARGs because of their co-occurrence with ARG subtypes. Redundancy analysis showed that the dissipation of ARGs during composting was linked to various environmental factors such as moisture. Bacterial succession as well as profile of biocide and metal resistance genes (BMRGs) were the determinants which constructed the antibiotic resistome during manure composting. However, the residues of ARGs and pathogens in compost products may still pose risks to human and crops after fertilization.
Epigallocatechin gallate (EGCG) has the effect to protect skin from ultraviolet B (UVB) induced damages, but it is unstable under ambient conditions, being susceptible to become brown in color. ...Gallocatechin gallate (GCG), an epimer counterpart of EGCG, is more stable chemically than EGCG. The potential effects of GCG against UVB-induced skin damages has not been available. The objective of this study was to investigate the protective effects of GCG against UVB-induced skin photodamages. GCG was topically applied on the skin of hairless mice at three dosage levels (LL, 12.5 mg/mL; ML 25 mg/mL; HL, 50 mg/mL), with EGCG and a commercially available baby sunscreen lotion SPF50 PA
as control. The mice were then irradiated by UVB (fluence rate 1.7 µmol/m
s) for 45 min. The treatments were carried out once a day for 6 consecutive days. Skin measurements and histological studies were performed at the end of experiment. The results show that GCG treatments at ML and HL levels inhibited the increase in levels of skin oil and pigmentation induced by UVB irradiation, and improved the skin elasticity and collagen fibers. GCG at ML and HL levels inhibited the formation of melanosomes and aberrations in mitochondria of UVB-irradiated skin in hairless mice. It is concluded that GCG protected skin from UVB-induced photodamages by improving skin elasticity and collagen fibers, and inhibiting aberrations in mitochondria and formation of melanosomes.
Antibiotics are widely used in animals for disease treatment and prevention. After use, these antibiotics end up in manure. Here we investigated the fate of veterinary antibiotics in animal manure ...during composting and their residues in manure-applied soils. The results showed that 64.7% of the detected veterinary antibiotics were removed after composting for 171 days, which mainly occurred at the thermophilic phase in the second week, followed by a long stable stage with limited variations. The removal rates for lincomycin, trimethoprim and the macrolides during the composting were >89.7%, while those for the sulfonamides, tetracyclines and fluoroquinolones were less than <63.7%. The dissipation of antibiotics during the composting was related to the change of compost physicochemical properties, especially moisture and C/N ratio. The application of compost products with antibiotic residues could still lead to soil contamination, which may pose risks of resistance selection to the soil ecosystem.
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•17 veterinary antibiotics were detected during the 171 days of composting.•Tetracyclines and lincomycin were predominant in initial compost.•64.7% of detected antibiotics were removed during composting.•The removal of antibiotics mainly occurred in thermophilic phage.•Usage of compost product posed high risk of resistance selection in soil ecosystem.
Microplastic (MP) has been identified as an emerging vector that transports hydrophobic organic compounds (HOCs) across aquatic environments due to its hydrophobic surfaces and small size. However, ...it is also recognized that environmental factors affect MP’s chemical vector effects and that attached biofilms could play a major role, although the specific mechanisms remain unclear. To explore this issue, an in situ experiment was conducted at Xiangshan Bay of southeastern China, and dynamics of HOCs (i.e., polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs)) and bacterial communities related to the model MP (i.e., PE fibers) were analyzed and compared. Through bacterial characterizations including the 16S rRNA approach, higher summer temperatures (31.4 ± 1.07 °C) were found to promote colonizing bacterial assemblages with larger biomasses, higher activity and more degrading bacteria than winter temperatures (13.3 ± 2.49 °C). Consequently, some sorbed pollutants underwent significant decline in the summer, and this decline was particularly the case for PAHs with low (2–3 rings) and median (4 rings) molecular weights such as phenanthrene (59.4 ± 1.6%), chrysene (70.6 ± 4.2%), fluoranthene (77.1 ± 13.3%) and benzaanthracene (71.5 ± 11.0%). In our winter test, however, most pollutants underwent a consistent increase throughout the 8-week exposure period. Moreover, more biorefractory pollutants including PCBs and high molecular weight (5–6 rings) PAHs accumulated regardless of bacterial characteristics. Two putative PAH-degrading bacteria appeared with high relative abundances during the summer test, i.e., family Rhodobacteraceae (18.6 ± 0.5%) and genus Sphingomicrobium (22.4 ± 3.6%), associated with drastic decreases in low (45.2 ± 0.4%) and median (66.0 ± 2.5%) molecular weight PAHs, respectively. Bacterial degradation effects of biofilms on PAHs are also supported by the correlative dynamics of salicylic acid, an important degradation intermediate of PAHs. The results of this study indicate that MP’s HOC vector effects are essentially determined by interactions between attached pollutants and microbial assemblages, which are further related to bacterial activity and pollutant features. Further studies of biofilm effects on MP toxicity and on the metabolic pathways of MP-attached HOCs are required.
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•Sorbed hydrophobic organic compounds can be degraded by attached bacteria.•Putative PAH-degrading bacteria appear with high relative abundances.•Temperature is a key factor in affecting biofilm’s biodegrading performance.•Biorefractory pollutants accumulate regardless of bacterial characteristics.
Phenolic endocrine disrupting chemicals (EDCs) may pose a great hazard to wildlife and humans, owing to their ubiquitous presence in the environment and potential bioaccumulation ability. We ...investigated the bioaccumulation, metabolism, and human health risks of six phenolic EDCs, including bisphenol A (BPA), 4-tert-octylphenol (4-t-OP), 4-nonylphenol (4-NP), estrone (E1), 17β-estradiol (E2), and 17α-ethinylestradiol (EE2), in wild fish from the Pearl River system, South China. Except EE2, the other five EDCs were detected in at least one of the four fish tissues (bile, liver, plasma, and muscle). The concentrations of BPA and 4-NP were greater than those of 4-t-OP, E1, and E2 in all tissues. The median values of log bioaccumulation factors for EDCs at the range of 3.86–4.52 in bile, 2.06–3.16 in liver, 2.69–3.87 in plasma, and 1.34–2.30 in muscle, indicating a higher bioaccumulation potential in fish bile than in other tissues. Greater levels of glucuronide/sulfate conjugated EDCs were found in fish bile and liver than in the plasma and muscle, suggesting that the liver and bile played an important role in the metabolism and excretion of phenolic EDCs in fish. The calculated hazard quotient values were below 1 for each compound, implying low risk to human health by intake of edible fish.
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•Higher levels of BPA and 4-NP were found than 4-t-OP, E1 and E2 in the four fish tissues.•Fish bile displayed greater bioaccumulation ability for the phenolic EDCs than liver, plasma and muscle.•Liver and bile played a significant role in metabolism and excretion of the phenolic EDCs in fish.•Consumption of edible wild fish muscle might not cause considerable risk to human health.
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•UASB and HDPE-BD could potently remove antibiotics and resistance genes.•Full-scale anaerobic digestion couldn’t effectively eliminate pathogens.•Bacterial flora, MGEs and BMRG ...profiles jointly structured the antibiotic resistome.•ARG-carrying host mainly belonged to Firmicutes, Bacteroidetes and Proteobacteria.•Bacteroides and Mycolicibacter were the ARG-carrying pathogens in digestate.
Anaerobic digesters have been widely used to treat wastewaters in livestock farms. With the increasing risk of antibiotic resistance originated from livestock husbandry, removal of antibiotics and antibiotic resistance genes (ARGs) via anaerobic digesters deserved more attention. Here we investigated the removal of antibiotics and ARGs in swine wastewater by three on-farm full-scale anaerobic digesters, including buried biogas digester (BBD), up-flow anaerobic sludge blanket (UASB) and high density polyethylene covered biogas digester (HDPE-BD). Variations of antibiotic resistome in swine wastewater were further revealed by metagenomic sequencing. Results showed the removal efficiencies for antibiotics, ARGs and mobile genetic elements (MGEs) varied in the three digesters, ranging from 65.1% to 98.1%, 3.5%-71.0% and 26.9%-77.2%, respectively. In general, UASB and HDPE-BD showed better removal efficiencies than BBD. However, enrichment of metal resistance genes (MRGs) was noted in UASB. Pathogens could not be effectively removed by all of the three digesters. What’s more, accumulation of pathogens was found in UASB (removal efficiencies: −8.5%-13.6%). Bacterial community succession, horizontal genetic transfer and biocide and metal resistance genes (BMRGs) profiles jointly structured the variation of antibiotic resistome during anaerobic digestion. A total of 334 high-quality bins were identified from swine wastewater, 96 of which belonged to phylum of Firmicutes, Bacteroidetes and Proteobacteria carried ARGs. Proteobacteria was the dominant multi-drug resistant flora. Meanwhile, ARG-carrying pathogens (Bacteroides and Mycolicibacter) were found in the swine wastewater, suggesting a potential threat to human and animal health. The findings from this study showed that HDPE-BD is the most eco-friendly and effective anaerobic digester in controlling risks from antibiotic resistance determinants in swine wastewater.
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