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Fluoride removal from aqueous solution by adsorption using fly ash cenospheres (FAC) modified with paper mill lime mud (LM) as composite adsorbent had been investigated. The characterization of FAC and composite adsorbent were analyzed by Scanning electron spectroscope (SEM), Energy dispersive spectrometer (EDS), Brunauer emmett teller (BET) and Fourier transform infrared (FTIR), which demonstrated that the porous structure of composite adsorbent was obtained after surface modification. Adsorption of fluoride on modified fly ash cenospheres was fitted with pseudo-second-order model and Langmuir model. Response surface methodology (RSM) was employed to investigate the effects of F− concentration, pH, adsorbent dosage and temperature on the removal efficiency. Analysis of variance (ANOVA) was used to test the adequacy of the mathematical models. The Nonelectrostatic model of modified fly ash cenospheres adsorbing fluoride was built through the Generalized composite method, indicating that two inner-spherical complexes, ≡SF and ≡SOHF−, were formed in the adsorption process by means of the ligand exchange and surface complexation. Optimization of the adsorption conditions enabled the realization of the practical needs for fluoride contaminated water. Image 1 • A low-cost fly ash cenospheres modified with paper mill lime mud adsorbent was prepared. • Response surface methodology was employed to research the effects on fluoride removal. • Nonelectrostatic model-Generalized composite approach had successfully described and predicted the adsorption process. • ≡SF and ≡SOHF− formed in the removal of fluoride via the ligand exchange and surface complexation. [ABSTRACT FROM AUTHOR]

Abstract Bioactive substances in the Biobio River Basin in Chile were examined by deploying Semi Permeable Membrane Devices (SPMDs) upstream and downstream of 4 pulp mill effluent discharges. Androgenic and estrogenic activity of SPMD extracts were then evaluated using in vitro fish sex steroid receptor binding assays. The results indicated the occurrence of estrogenic type compounds associated with one of the mill discharges. A significant correlation among the presence of these compounds, an increase in gonadosomatic index GSI and induction of hepatic EROD activity of two native fish species was observed. However, no significant presence of mature oocytes in female gonads was detected. Although EROD induction was observed in sites impacted by mill effluents, an increase of its activity occurred towards the downstream areas, suggesting other non-mill sources. More research is needed to understand the environmental changes in context of the new technological improvements in treatment systems to MBBR (Moving Bed Biofilm Reactor) recently implemented by the pulp mill industries. Highlights • Hormonally active substances were captured by SPMDs downstream pulp mill effluents. • Estrogenic type compounds were related to increased GSI in two wild fish species. • EROD activity depends on benthic behavior and spawning period of the wild fish species. • Chilean pulp mill effluents effects on fish reproduction are different from some Canadian mills. [ABSTRACT FROM AUTHOR]

Abstract Background Heavy metal contamination is becoming a limitation to the utilization of soil and the distribution of vegetation. In particular, cadmium (Cd) pollution has had a serious impact on the food chain. Broussonetia papyrifera is a widely distributed pioneer tree species of heavy metal contaminated areas with important economic value. However, little is known about the genomic background of the Cd-tolerance mechanism in B. papyrifera. Results The CdCl 2 responsive physiology was evaluated and proved to be involved in antioxidase activity and active oxygen species (ROS) accumulation. The leaf and root transcriptomes derived from B. papyrifera grown under normal and CdCl 2 stress conditions were systematically investigated using the Illumina HiSeq method. A total of 180,678,660 bp (27.1 GB) clean reads were assembled into 589,487 high-quality unigenes, of which 256,025 (43.43% of the total) and 250,251 (42.45% of the total) were aligned in Gene Ontology (GO) and Protein family (Pfam), respectively. A total of 24,414 differentially expressed genes (DEGs) were GO-annotated into 53, 23, 55, and 60 terms from the transcriptomes of root and leaf tissues under Cd stress and control conditions. A total of 117,547 Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology (KO)-annotated DEGs were enriched in at least 47 KEGG pathway terms among the four comparisons. Many genes encoding important transcription factors (e.g., auxin/indole-3-acetic acid (AUX/IAA), basic helix-loop-helix (bHLH), DNA-binding one zinc finger (Dof), and MYB) and proteins involved in plant-pathogen interactions, phenylpropanoid biosynthesis, plant hormone signal transduction, oxidative phosphorylation, carbon fixation, peroxisomes, flavonoid biosynthesis, and glutathione metabolism, among others, were substantially upregulated under CdCl 2 stress. Conclusions These genes represent important candidates for studying Cd-response mechanisms and molecular biology of B. papyrifera and related species. Our findings provide a genomic sequence resource for functional genetic assignments in B. papyrifera , which will help elucidate the molecular mechanisms of its Cd-stress responses and facilitate the bioremediation of heavy metal contaminated areas via breeding of new stress-tolerant cultivars. Graphical abstract fx1 Highlights • Broussonetia papyrifera respond to Cd stress involving in reactive oxygen species and antioxidant enzyme metabolic pathway. • Abundant important Cd response related genes and regulation pathways that involving in ABA and auxin signal were identified. • The gene resource of B. papyrifera will help elucidate the molecular mechanisms of Cd-stress responses. [ABSTRACT FROM AUTHOR]

We studied the avoidance behaviour of the earthworm Eisenia fetida towards Cd, Cu, and Zn, trace elements (TEs) tested as chloride, nitrate and sulphate salts. Sub adults were exposed individually using dual-cell chambers at 20 + 2 °C in the dark. Recordings were realised at different dates from 2 h to 32 h. We used filter paper and extruded water agar gel as exposure media to evaluate the contribution of the dermal and the digestive exposure routes on the avoidance reactions. Exposures to Cu or Cd (10 mg metal ion L −1 ) resulted in highly significant avoidance reactions through the exposure duration. Worms avoided Zn poorly and reactions towards Zn salts varied along the exposure. Worm sensitivity towards TEs differed between salts and this could result from differential toxicity or accessibility of these TE salts to earthworms. The anion in itself was not the determinant of the avoidance reactions since exposures to similar concentrations of these anions using calcium salts did not result in significant avoidance worm behaviour. Avoidance responses towards TEs were higher in the case of water agar exposures than in filter paper exposures. Thus, dermal contacts with TE solutions would elicit worm avoidance but signals from receptors located inside the digestive tract could reinforce this behaviour. The use of extruded water agar gels as the substrate allows checking the real sensitivity of earthworm species towards TEs since the TE concentrations leading to significant avoidance reactions were below those reported in the literature when using TE-spiked soils. [ABSTRACT FROM AUTHOR]

Economic benefits of the pulp and paper industry have led it to be one of the most important industrial sections in the world. Nevertheless, in recent years, pulp and paper mills are facing challenges with the energy efficiency mechanisms and management of the resulting pollutants, considering the environmental feedbacks and ongoing legal requirements. This study reviews and discusses the recent developments of affordable methods dealing with pulp and paper mill wastewaters. To this end, the current state of the various processes used for pulp and paper production from virgin or recovered fibers has been briefly reviewed. Also, the relevant contaminants have been investigated, considering the used raw materials and applied techniques as the subject for further discussion about the relevant suitable wastewater treatment methods. The results of the present study indicated that adopting the integrated methods, alongside a combination of biological (e.g., anaerobic digestion) and physicochemical (e.g., novel Fenton reactions) treatment methods, can be environmentally and economically preferable to minimize environmental contaminants and energy recycling. [ABSTRACT FROM AUTHOR]

This work presents the results of removing heavy metals from paper mill wastewater (PMS) sludge spiked with cow dung (CD) employing Eisenia fetida. A total of seven set-ups were prepared: CD (100 percent), PMS: CD (1:3), PMS:CD (1:2), PMS:CD (1:1), PMS (100 percent), PMS:CD (3:1) and PMS:CD (2:1) and changes in chemical parameters were observed for 60 days. Vermistabilization caused the significant decrease in the level of Cd (32–37 percent), Cr (47.3–80.9 percent), Cu (68.8–88.4 percent), and Pb (95.3–97.5 percent) and substantial increase in EC, total-N, available P and K at the end. At the end, the tissues of inoculated worms showed the high load (mg kg−1, dry biomass) of Pb (8.81–9.69), Cd (2.31–2.71), Cr (20.7–35.9) and Cu (9.94–11.6), respectively which indicated bioaccumulation of metals by worms. The PMS:CD (2:1 and/or 3:1) appeared to be suitable waste mixture in terms of high metal removal and earthworm growth rates. Bioaccumulation, as quantified using BCF, was in the order: Cd>Cr>Pb>Cu. Results suggested vermiremediation as appropriate technology for bioremediation of heavy metals from PMS. [ABSTRACT FROM AUTHOR]

This study investigates whether pulse exposure to Chilean pulp and paper mill effluent solid phase extracted (SPE) extracts via intraperitoneal injection (IP), would result in changes in the activities of the respiratory metabolic enzymes citrate synthase (CS) and lactate dehydrogenase (LDH) in rainbow trout livers. It also investigated if an alteration in liver metabolic capacity influenced the liver detoxification processes and estrogenic effects previously reported. Besides, a comparison of those enzymatic activities with fish IP injected with SPE extracts of two model effluents coming from industries that process 100% different type of feedstock (softwood, SW and hardwood, HW) was also evaluated. An initial induction of the anaerobic metabolism (increase in LDH enzymatic activity) was detected in all Chilean pulp mill effluent extracts evaluated, contrary to the initial unaltered aerobic metabolism (CS enzymatic activity) observed. A compensatory relationship in energy metabolism (Pasteur effect) was observed when comparing both enzymatic activities of fish exposed to those effluent extracts. LDH and CS activities observed in fish injected with Chilean extracts seem to be related to the effects observed in fish injected with SW extracts. This study showed that intraperitoneal injection of pulp and paper mill effluent extracts affected the anaerobic and aerobic metabolic capacities in rainbow trout livers, but this metabolic alteration did not affect detoxification capability or estrogenic effect previously reported. [Copyright &y& Elsevier]

The objective of this study was to evaluate the effects of bleached/unbleached kraft mill effluents (B/UKME) on the reproductive parameters of free-ranging Florida largemouth bass (Micropterus salmoides floridanus). The reproductive parameters measured included gonadosomatic index (GSI), histological evaluation of gonads, and plasma concentrations of vitellogenin (VTG), 17β-estradiol, and 11-ketotestosterone (11-KT). Hepatic ethoxyresorufin-O-deethylase (EROD) activity was measured as a marker of exposure to cytochrome P450-inducing agents in these effluents. Endpoints were compared among adult bass sampled from tributary and mainstream effluent-contaminated and reference sites. Females sampled from the site closest to the mill outfall had a significant five-fold increase in EROD activity compared to bass sampled from reference streams. Although sex hormones were significantly reduced in bass from exposed sites, there were no differences in VTG and GSI across sites. The absence of organism-level responses was probably not related to a lack of sensitivity, as previous studies in our laboratory have shown that bass exposed to these effluents exhibit changes in GSI and in other measures associated with reproductive success. In females, inverse relationships were observed between VTG and GSI and EROD activity. These relationship, however, were not consistent within all of the sites studied. Collectively, our findings indicate that hepatic EROD induction is an effective marker of B/UKME exposure in largemouth bass and that it might be associated with antiestrogenic effects in this species. [Copyright &y& Elsevier]

Pulp and paper mill wastewater (PPMWW) contains high concentrations of recalcitrant compounds that cause toxicity to organisms. Advanced oxidation processes (AOPs) have the ability to degrade these compounds and reduce overall toxicity. Physicochemical characterization and Lactuca sativa toxicity test were conducted to compare the effectiveness of two post-treatments: UV/H 2 O 2 and photo-Fenton. A comparison of four phytotoxicity indexes was carried out. PPMWW from a Brazilian treatment plant was characterized by high values of phenols, color, integrated spectral area (ISA), and chemical oxygen demand (COD), and caused significant inhibition to seedling development. The use of both post-treatments allowed the removal of over 75% of phenols, color, ISA, and COD. Although UV/H 2 O 2 was more effective in removing phenols and ISA, photo-Fenton better reduced phytotoxicity. The most sensitive phytotoxicity indexes were RGIC 0.8 and GIC 80% , whereas SGC 0 , REC -0.25 and REC -0.50 better showed the effectiveness of the post-treatments. We suggest the combined use of two phytotoxicity indexes: one that evaluates the effects on seed germination and, another, on root elongation, e.g., SGC 0 and RGIC 0.8. Additionally, we recommend the use of ISA for monitoring programs of wastewater treatments because it is a cost-effective approach that allows narrowing down the search and identification of compounds present in complex mixtures. Image 1 • PPMWW was post-treated by two AOPs: UV/H 2 O 2 and photo-Fenton. • Phenols, ISA and COD correlated negatively with germination and root elongation. • UV/H 2 O 2 better removed phenols and ISA, but photo-Fenton better reduced toxicity. • The most sensitive phytotoxicity indexes were RGIC 0.8 and GIC 80%. • SGC 0 , REC -0.25 and REC -0.50 better showed the effectiveness of the AOPs. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the acute toxicity of pulp-paper industry wastewater using traditional and enrichment toxicity tests and to emphasize the importance of toxicity tests in wastewater discharge regulations. Enrichment toxicity tests are novel applications and give an idea of whether there is potential toxicity or growth-limiting and -stimulating conditions. Different organisms were used such as bacteria (floc and coliform bacteria), algae (Chlorella sp.), protozoa (Vorticella sp.), and fish (Lepistes sp.) to represent four trophic levels. Furthermore, chemical oxygen demand (COD) fractionation results were compared with these tests to assess the effect of COD subcategories on the determination of possible toxicity. The pulp-paper industry results revealed acute toxicity to at least two organisms in 6 of 20 effluent samples. The toxicity test results were assessed with chemical analyses such as COD, biochemical oxygen demand (BOD), color, absorbable organic halogen (AOXs), and phenol. It was observed that the toxicity of the effluents could not be explained by using physicochemical analyses in four cases for the pulp-paper industry. The results clearly indicate that bioassay tests provide additional information on the toxicity potential of industrial discharges and effluents. [Copyright &y& Elsevier]

Long-term studies on the reproductive fitness of fish under controlled exposure conditions are necessary to address some of the controversy surrounding the field-based studies of pulp and paper effluent effects. This study undertook effluent exposures of 2+ age rainbow trout that were approximately halfway through gonadal growth. Trout were exposed to a mixed thermomechanical/bleached kraft effluent in 12,000-L flow-through exposure tanks at an environmental research facility located at a pulp and paper mill in Kawerau, New Zealand. Trout were exposed to either upstream river water or 10% effluent in upstream river water and were maintained at a ration of 0.7% of body wet weight during the experiment. Results of the 2-month study indicated that trout survival was not significantly different between effluent-exposed tanks and reference tanks. There was extensive growth during the exposure but no differences were found due to effluent exposure. Gonadal development was not significantly different between treatments. Steroid hormone concentrations in males and females were not affected by effluent exposure. The effluent showed no potential to be estrogenic as indicated by a lack of vitellogenin induction in male trout. Other physiological indicators of energy storage and utilization also showed no significant differences. Modest induction of hepatic 7-ethoxyresorufin-O-deethylase (2.5-fold) was the only detectable biological effect of the exposure. Biliary concentration of effluent-related compounds were typical of pulp mill effluent exposure and further suggested that the source of phytosterols was in fact dietary and not effluent-derived. [Copyright &y& Elsevier]

Abstract: Two experiments using rainbow trout (Oncorhynchus mykiss) were conducted to examine the combined effects of energy intake as manipulated by ration and pulp and paper mill effluent exposure over either one, or two consecutive reproductive cycles. This study demonstrated that the level of energy intake affected the full range of measured parameters from energy allocation to somatic growth and the gonadal development, steroid production and hematology. Increasing ration level expectedly increased growth, condition, liver and gonad size. Female trout in the higher ration treatments produced more follicles and had larger eggs, investing the same relative proportion of total energy into ovarian development. Sex steroid levels and hematological parameters were also positively influenced by increasing ration level in males and females. By far, the most dramatic impact of reduced ration on reproduction was to substantially reduce the frequency of sexually maturing fish. The effects of effluent exposure were not as marked as those linked to ration level and typically did not manifest unless fish were exposed through two consecutive reproductive cycles. The physiological effects of pulp and paper effluent exposure observed in these experiments were not consistent between the two experiments conducted herein, nor were they consistent with previously observed impacts in similar experiments with this effluent. Effluent exposure over one reproductive cycle did not impact physiological parameters in trout. However, when effluent exposure was maintained over two reproductive cycles, a new pattern of effluent response emerged including increased condition factor in both sexes, a decrease in the potential ability of the blood of females to transport oxygen, and increased sex steroids and reproductive investment in males. Effluent was also observed to cause reduced growth in male trout over two years. The effects of ration on gonad and liver size were far more obvious and consistent when a longer exposure was employed, thus, it appears to take more than one full year for energy intake changes to be reflected in those particular physiological endpoints. [Copyright &y& Elsevier]

Abstract: Aquatic habitat is affected by paper mill effluent discharge in many ways. The effect of paper mill effluent on the gill ATPases was studied in freshwater fish Channa punctata (Bloch) exposed to 1%(v/v) of effluent for 15, 30, and 60 days. There was a time-dependent significant (P<0.05–0.001) decrease in all the ATPase activities measured, viz., total, Na+, K+- and ouabain-insensitive ATPase in gill. ATPases play an important role in maintenance of functional integrity of plasma membrane and in several intracellular functions and are considered to be a sensitive indicator of toxicity. In addition to this, branchial ATPases are intimately involved in osmoregulation, acid–base regulation, and respiration of fish. The inhibition of ATPases in gills by, e.g., paper mill effluent could cause disruption of these processes. It is suggested that measurement of ATPases could also be used as a surrogate biomarker of exposure to chemical pollutants. [Copyright &y& Elsevier]

Abstract: Online medical information, when presented to clinicians, must be well-organized and intuitive to use, so that the clinicians can conduct their daily work efficiently and without error. It is essential to actively seek to produce good user interfaces that are acceptable to the user. This paper describes the methodology used to develop a simplified heuristic evaluation (HE) suitable for the evaluation of screen shots of Web pages, the development of an HE instrument used to conduct the evaluation, and the results of the evaluation of the aforementioned screen shots. In addition, this paper presents examples of the process of categorizing problems identified by the HE and the technological solutions identified to resolve these problems. Four usability experts reviewed 18 paper-based screen shots and made a total of 108 comments. Each expert completed the task in about an hour. We were able to implement solutions to approximately 70% of the violations. Our study found that a heuristic evaluation using paper-based screen shots of a user interface was expeditious, inexpensive, and straightforward to implement. [Copyright &y& Elsevier]

Abstract: Experiments were conducted to examine the effects of a thermomechanical (TMP)/bleached kraft pulp and paper mill effluent (BKME), dehydroabietic acid (DHAA), hypoxia, and combinations of hypoxia and effluent on juvenile rainbow trout. In the first two experiments, trout were exposed for 4 weeks to 0%, 10%, 30%, and 70% TMP/BKME or 0, 35, 110, and 250μgL−1 DHAA, respectively. Endpoints of those dose–response studies included critical swimming speed, oxygen consumption, and hematology. Reduced swimming performance was found for fish exposed to 70% TMP/BKME. Moderate increases in mean cell hemoglobin concentration at 70% TMP/BKME and blood glucose at 30% and 70% TMP/BKME were also seen. The opposite trend for glucose was found for DHAA-exposed fish, where a slight decrease in glucose was seen at 110 and 250μgL−1 DHAA. The third experiment examined the effects of 15% v/v TMP/BKME exposure at 2.5 and 5.0mgL−1 dissolved oxygen (DO) for 4 weeks. This experiment found no effect of low DO on swimming ability. An interactive effect between DO and effluent exposure was seen only on hematocrit, where effluent caused an increase in hematocrit at 5mgL−1 and a decrease at 2.5mgL−1 DO. Effluent exposure in this experiment resulted in a greater number of smaller red blood cells. The current study demonstrated physiological effects in rainbow trout exposed to varying concentrations (15–70% v/v) of a TMP/BKME and no substantial effects of DHAA exposure. With the exception of the reduced swimming performance in fish exposed to TMP/BKME, the observed effects are considered relatively small in magnitude but are occurring at concentrations of effluent that occur in the receiving environment. [Copyright &y& Elsevier]

Combining adsorption and photocatalysis is an effective strategy for degrading organic pollutants. Here, BiVO 4 @diatomite composite photocatalyst (BiVO 4 @diatomite CP) was prepared by hydrothermal synthesis from Bi(NO 3) 3 ·5H 2 O glycerin solution, NH 4 VO 3 solution and diatomite. BiVO 4 @diatomite/microcrystalline cellulose/PVB composite fibers (BiVO 4 @diatomite/MCC/PVBCFs) were prepared from BiVO 4 @diatomite CPs, microcrystalline cellulose (MCC) and PVB ethanol solution using the electrospinning method. BiVO 4 @diatomite/MCC/PVBCFs were then mixed with pulp fibers to prepare the visible light-responsive photocatalytic paper. BiVO 4 @diatomite CP with a BiVO 4 /diatomite ratio of 6:4 had good interface states and displayed good photocatalytic activity with 64.32% degradation of methylene blue (MB) after 4 h. A PVB ethanol solution (6%) was formulated with BiVO 4 @diatomite CP and MCC to provide an ethanol spinning solution (12% solid) to prepare BiVO 4 @diatomite/MCC/PVBCFs (3:3:4). The resulting fibers had smooth surfaces, compact structures and exhibited good photocatalytic activity (66.80% and 56.80% degradation of MB and formaldehyde (HCHO), respectively, after 4 h). Photocatalytic paper containing 18% BiVO 4 @diatomite/MCC/PVBCFs had good photocatalytic activity with 50.20% degradation of HCHO after 4 h. This paper also had good physical properties and has the potential to be used for the photocatalytic degradation of indoor air pollutants, such as HCHO. • Adsorption and photocatalysis synergy for degrading MB and HCHO. • High degradation rates of MB and HCHO under visible light. • More potential application fields for paper. [ABSTRACT FROM AUTHOR]

The coronavirus disease (COVID-19) has claimed the lives of over 350,000 people and infected more than 173 million people worldwide, it triggers researchers from diverse fields are accelerating their research to help diagnostics, therapies, and vaccines. Researchers also publish their recent research progress through scientific papers. However, manually writing the abstract of a paper is time-consuming, and it increases the writing burden of the researchers. Abstractive summarization technique which automatically provides researchers reliable draft abstracts, can alleviate this problem. In this work, we propose a linguistically enriched SciBERT-based summarization model for COVID-19 scientific papers, named COVIDSum. Specifically, we first extract salient sentences from source papers and construct word co-occurrence graphs. Then, we adopt a SciBERT-based sequence encoder and a Graph Attention Networks-based graph encoder to encode sentences and word co-occurrence graphs, respectively. Finally, we fuse the above two encodings and generate an abstractive summary of each scientific paper. When evaluated on the publicly available COVID-19 open research dataset, the performance of our proposed model achieves significant improvement compared with other document summarization models. [ABSTRACT FROM AUTHOR]

Considering plastic exposure patterns in modern society, the effects of exposure to leachate from boiled-water treated plastic products on cognitive function was probed in mice through changes in gut microbiota diversity. In this study, Institute for Cancer Research (ICR) mice were used to establish drinking water exposure models of three popular kinds of plastic products, including non-woven tea bags, food-grade plastic bags and disposable paper cups. 16S rRNA was used to detect changes in the gut microbiota of mice. Behavioral, histopathology, biochemistry, and molecular biology experiments were used to evaluate cognitive function in mice. Our results showed that the diversity and composition of gut microbiota changed at genus level compared to control group. Nonwoven tea bags-treated mice were proved an increase in Lachnospiraceae and a decreased in Muribaculaceae in gut. Alistipes was increased under the intervention of food grade plastic bags. Muribaculaceae decreased and Clostridium increased in disposable paper cups group. The new object recognition index of mice in the non-woven tea bag and disposable paper cup groups decreased, and amyloid β-protein (Aβ) and tau phosphorylation (P-tau) protein deposition. Cell damage and neuroinflammation were observed in the three intervention groups. Totally speaking, oral exposure to leachate from boiled-water treated plastic results in cognitive decline and neuroinflammation in mammals, which is likely related to MGBA and changes in gut microbiota. [Display omitted] • Long-term plastic oral heat exposure causes gut microbiota imbalance in mice. • Long-term plastic oral heat exposure decreases cognitive function in mice. • Decline in cognitive function likely mediated by gut bacteria. • Microbial gut-brain axis and neuroinflammation play a role. [ABSTRACT FROM AUTHOR]

A large amount of lignocellulosic waste is generated every day in the world, and their accumulation in the agroecosystems, integration in soil compositions, or incineration for energy production has severe environmental pollution effects. Using enzymes as biocatalysts for the biodegradation of lignocellulosic materials, especially in harsh processing conditions, is a practical step towards green energy and environmental biosafety. Hence, the current study focuses on enzyme computationally screened from camel rumen metagenomics data as specialized microbiota that have the capacity to degrade lignocellulosic-rich and recalcitrant materials. The novel hyperthermostable xylanase named PersiXyn10 with the performance at extreme conditions was proper activity within a broad temperature (30–100 ℃) and pH range (4.0–11.0) but showed the maximum xylanolytic activity in severe alkaline and temperature conditions, pH 8.0 and temperature 90 ℃. Also, the enzyme had highly resistant to metals, surfactants, and organic solvents in optimal conditions. The introduced xylanase had unique properties in terms of thermal stability by maintaining over 82% of its activity after 15 days of incubation at 90 ℃. Considering the crucial role of hyperthermostable xylanases in the paper industry, the PersiXyn10 was subjected to biodegradation of paper pulp. The proper performance of hyperthermostable PersiXyn10 on the paper pulp was confirmed by structural analysis (SEM and FTIR) and produced 31.64 g/L of reducing sugar after 144 h hydrolysis. These results proved the applicability of the hyperthermostable xylanase in biobleaching and saccharification of lignocellulosic biomass for declining the environmental hazards. [Display omitted] • Novel xylanase was mined from the metagenomic data by the in-silico screening. • PersiXyn10 showed remarkable tolerance at a wide range of temperatures and pH. • Strong thermostable properties were found for PersiXyn10 by biophysical experiments. • The hyperthermostable xylanase was effectively used for biobleaching of pulp paper. [ABSTRACT FROM AUTHOR]

Abstract The available information is insufficient to enable a reliable understanding of the global distribution and effect of organic ultraviolet absorbents (UVAs) on ecosystems. Little is known about the pollution of China's lakes by these chemicals. We conducted a survey of UVAs in water and sediment from Lake Chaohu and its inflowing rivers. The UVAs were widely present in this area and the concentrations of total 12 UVAs (Σ 12 UVAs) ranged between 162 and 587 ng/L in water and 9.70–178 ng/g in sediment. Benzophenone and benzophenone-3 were dominant in water, and benzophenone and octocrylene dominated in sediment. Higher concentrations of benzophenone were detected in the investigated water samples, although the contamination levels of UVAs in this study were comparable to those investigated in other areas. In addition to the inputs from the UVAs used as filters in cosmetics, the discharge from industries using UVAs as stabilizers also contributed much to the pollution in the study waters. Generally, the risk to aquatic organisms from exposure to UVAs in this area was low, but further research is needed to elucidate the fate of UVAs and to understand bioaccumulation and associated risks. Highlights • The 12 UVAs were widely present in Lake Chaohu and its inflowing rivers. • Higher level of benzophenone was detected in the investigated water samples. • Discharge from industries was an important source of UVAs in this area. • The ecological risks of UVAs in this area were generally within low levels. [ABSTRACT FROM AUTHOR]

This work reports the details of the design components and materials used in a linear compound parabolic trough reactor constructed with an aim to use the photocatalyst for solar photocatalytic applications. A compound parabolic trough reactor has been designed and engineered to exploit both UV and visible part of the solar irradiation. The developed compound parabolic trough reactor could receive almost 88% of UV radiation along with a major part of visible radiation. The performance of the reactor has been evaluated in terms of degradation of a probe pollutant using the parameters such as rate constant, residence time and photonic efficiency. An attempt has been made to assess the performance in different ranges of solar spectrum. Finally the developed reactor has been employed for the photocatalytic treatment of a paper mill effluent using Degussa P25 as the photocatalyst. The paper mill effluent collected from Nagaon paper mill, Assam, India has been treated under both batch mode and continuous mode using Degussa P25 photocatalyst under artificial and natural solar radiation, respectively. The photocatalytic degradation kinetics of the paper mill effluent has been determined using the reduction in total organic carbon (TOC) values of the effluent. [ABSTRACT FROM AUTHOR]

Recent studies have shown that dehydroabietic acid (DHAA), a resin acid present in pulp and paper mill effluent, affects liver energy metabolism and may have anti-estrogenic effects in fish. A chronic-exposure toxicity experiment using immature rainbow trout (Oncorhynchus mykiss) was conducted in order to assess the endocrine disrupting and liver metabolic effects of the model estrogen 17β-estradiol (E2) and the wood extractives DHAA and β-sitosterol (BS), regularly present in pulp and paper mill effluents. Exposure to 5ppm of E2 significantly increased hepatosomatic index (HSI), vitellogenin (VTG) and plasma sorbitol dehydrogenase (SDH). This latter effect was reduced by mixing E2 with DHAA, indicating that DHAA does not cause its endocrine disrupting effects indirectly due to liver damage. Exposure to 0.5ppm of DHAA as well as all the DHAA mixed treatments caused significant increases in liver citrate synthase (CS), activity after 7 days, however, the fish returned to control values by 28 days. Results indicate that DHAA may alter metabolic enzyme activity as well as alter the effects of E2 in juvenile rainbow trout. [Copyright &y& Elsevier]

Examining the concentration and types of airborne bacteria in waste paper and cardboard sorting plants (WPCSP) is an urgent matter to inform policy makers about the health impacts on exposed workers. Herein, we collected 20 samples at 9 points of a WPCSP every 6 winter days, and found that the most abundant airborne bacteria were positively and negatively correlated to relative humidity and temperature, respectively. The most abundant airborne bacteria (in units of CFU m−3) were: Staphylococcus sp. (72.4) > Micrococcus sp. (52.2) > Bacillus sp. (30.3) > Enterococcus sp. (24.0) > Serratia marcescens (20.1) > E. coli (19.1) > Pseudomonas sp. (16.0) > Nocardia sp. (1.9). The lifetime average daily dose (LADD) for the inhalation and dermal routes for the intake of airborne bacteria ranged from 3.7 × 10−3 ≤ LADD Inhalation ≤ 2.07 × 101 CFU (kg d)−1 and 4.75 × 10−6 ≤ LADD Dermal ≤ 1.64 × 10−5 CFU (kg d)−1, respectively. Based on a sensitivity analysis (SA), the concentration of airborne bacteria (C) and the exposure duration (ED) had the most effect on the LADD Inhalation and LADD Dermal for all sampling locations. Although the Hazard Quotient of airborne bacteria was HQ < 1, an acceptable level, the indoor/outdoor ratio (1.5 ≤ I/O ≤ 6.6) of airborne bacteria typically exceeded the threshold value (I/O > 2), indicating worker's exposure to an infected environment. Therefore, in the absence of sufficient natural ventilation the indoor ambient conditions of the WPCSP studied should be controlled by supplying mechanical ventilation. [Display omitted] • Airborne bacteria from waste paper and cardboard sorting plant were studied. • Health risks to plant workers regarding exposure to airborne bacteria were quantified. • The ratio of indoor bacteria to outdoor bacteria (I/O) ranged from 1.5 to 6.6. • LADDs for bacteria ranged from 4.75 × 10−6 to 2.07 × 101 CFU (kg d)−1. • Bacterial exposure during sorting of waste increases with increased suspended particles. [ABSTRACT FROM AUTHOR]

Abstract: Resin acids, a class of wood extractives, are potential toxic constituents in many pulp and paper mill effluents. In the present investigation, the effects of two predominant resin acids, dehydroabietic acid (DHA) and abietic acid (ABA), on survival, reproduction, and growth of the freshwater crustacean Daphnia magna were assessed over its life cycle. Based on the experimentally determined acute toxicity data (48-h EC50''s) for DHA (7.48mg/L) and ABA (7.98mg/L), D. magna was treated chronically with each resin acid at nominal concentrations of 0, 0.25, 0.5, 1.0, 2.0, 4.0, and 8.0mg/L for 21 days. Both DHA and ABA at concentrations as high as 4.0mg/L did not affect physiological and reproductive parameters such as time to maturation, number of molting, number of broods, and number of offspring produced from surviving daphnids, while significant mortality was observed only at 8.0mg/L in both cases. However, a small but statistically significant decrease in Daphnia growth (body length) at the end of exposure was detected at concentrations as low as 0.5mg/L for DHA and 1.0mg/L for ABA, respectively. These results indicated that both DHA and ABA had the potential to exhibit weak growth inhibition without apparent negative effects on reproduction to D. magna at nonlethal concentration levels. This slight effect is not expected to be ecologically significant because the concentrations of DHA and ABA in biologically treated pulp and paper mill effluents are well below the effective levels observed in the present study. [Copyright &y& Elsevier]

The present paper describes a new and efficient method for registration of retinal angiogram. The presence of noise, the variations in the background, and the temporal variation of fluorescence level poses serious problems in obtaining a robust registration of the retinal image. Here, a multiscale registration scheme is proposed which comprises of three steps. The first step of this work proposes an edge preserving smoothing of the vascular tree. This morphological filtering approach is based on opening and closing with a linear rotating structuring element. For complete preservation of the linear shape of the vascular structures, a morphological reconstruction by dilation of the opened image and a reconstruction by erosion of the closed image are applied. It is proposed to compute the registration transform between two successive original frames, from their morphological gradient. Then, the second step consists in computing the morphological gradient of the two filtered images and radiometrically correcting these gradient images. To take into account the intensity variations, our model incorporates two constant multiplicative and additive factors (based on contrast and brightness) estimated employing a simple analysis of the local histograms (based on a sliding window). In the third step, the proposed method computes the registering transform through a coarse-to-fine (or multiscale) hierarchical approach. After computing the dominant registering transform (which implies the translation) between two successive frames, an elastic transform (also called local affine transform) is carried out to achieve a residual correction. The proposed method is tested by experimental studies, performed on macular fluorescein and Indo cyanine green angiographies. It has been sufficiently demonstrated that our proposed registering method is robust, accurate and fully automated, and it is not based on the extraction of the features or landmarks. [Copyright &y& Elsevier]

Abstract: Anadramous Atlantic salmon (Salmo salar L.) returning to Exploits River, Newfoundland, Canada, to spawn encounter low concentrations of thermomechanical pulp (TMP) effluent as they migrate upstream past an integrated newsprint mill. Various physiological responses of adult Atlantic salmon from the Exploits River were studied under laboratory conditions. The effects of a 6-h exposure to 0%, 6%, 12%, or 25% (v/v) TMP effluent or an increasing concentration gradient of effluent (0–25%) on cardiac output , critical swimming performance (U crit), hematocrit, and blood glucose, cortisol, lactate, and osmolality were examined. Relative to other treatment groups, during routine and low-level activity was 7–10% higher in fish exposed to at least 12% effluent. The 25% exposure group had a distinctly lower U crit and scope for increase in than the other treatment groups. These findings suggest that effluent exposure elevates physiological maintenance and repair costs, resulting in a reallocation of energetic resources. [Copyright &y& Elsevier]

Given the high content of Ca2+ in waste paper recycling wastewater, the anaerobic granular sludge (AnGS) undergoes calcification during wastewater treatment and affects the treatment efficiency. To restore the activity of calcified AnGS and improve the performance of AnGS, four types of N-acyl-homoserine lactones (AHLs) were added to the AnGS system while papermaking wastewater treatment. The addition of N-butyryl-DL-homoserine lactone(C4-HSL) and N-octanoyl-DL-homoserine lactone (C8-HSL) had an inhibitory affect the COD removal efficiency and SMA of sludge at the inception. The addition of N-hexanoyl-L-homoserine lactone (C6-HSL) has no obvious effect on the COD removal efficiency, but can improve the SMA of sludge more obviously. The addition of N-(β-ketocaproyl)-D L -homoserine lactone (3O-C6-HSL) can increased COD removal efficiency and promoted SMA together obviously. The addition of C6-HSL and 3O-C6-HSL can increase volatile suspended solid (VSS)/total suspended solid (TSS), and regulate extracellular polymeric substance (EPS) secretion in AnGS. Analysis of microbial sequencing revealed changes in the microbial community structure following AHL addition, which enhanced the methane metabolism pathway in sludge. The addition of C6-HSL, C8-HSL, and 3O-C6-HSL increased Methanosaeta population, thus increasing the aceticlastic pathway in sludge. Thus, exogenous AHLs can play an important role in regulating microbial community structure, and in improving the performance of AnGS. • Adding specific AHLs can improve the performance of calcified AnGS. • AHLs can adjust the community structures of bacteria and archaea. • Specific AHLs can enhance the methane metabolism pathway of sludge. [ABSTRACT FROM AUTHOR]