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Based on the important feature of sulfur with excellent selectivity toward selenite in the presence of selenate, a simple and low-cost adsorbent of solid phase extraction known as sulfur loading activated carbon (SAC-6) was successfully prepared and applied for selenite (Se(IV)) analysis in water. Microstructure and morphological characteristics of SAC-6 had been identified by XRD, TEM, BET and FT-IR. In the static adsorption experiments, Se(IV) could be separated in a wide range of pH values (pH=3-11). The retention process of Se(IV) onto SAC-6 was characterized as spontaneous exothermic reaction. An obvious change of adsorption mechanism occurred in static and dynamic adsorption processes shown that the behaviors followed monolayer and hybrid adsorption. The theoretical maximum adsorption capacity of SAC-6 calculated by Langmuir-Freundlich was 13.48 mg/g. The microcolumn filled with SAC-6 was applied to extract Se(IV) in water solution. The detection limit of Se(IV) analytical procedure was confirmed as 0.27 μg/L within a linear range of 10-1000 μg/L. A good precision with relative standard deviation of 1.34 % (100 μg/L, n = 6) was achieved. The high adaptability and accuracy of SAC-6 microcolumn was validated by analyzing natural water samples and certified reference materials. Our work successfully excavated the application value of the sulfur selectivity, and also provided a new adsorbent for Se(IV) extraction and analysis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements (REEs) as emerging pollutants in atmospheric environment. In this study, the variation of REEs in PM 2.5 with urban (a non-mining city) transformation was investigated through five consecutive years of sample collection. The compositional variability and provenance contribution of REEs in PM 2.5 were characterized, and the REEs exposure risks of children and adults via inhalation, ingestion and dermal absorption were also evaluated. The results showed an increase in the total REEs concentration from 46.46 ± 35.16 mg/kg (2017) to 81.22 ± 38.98 mg/kg (2021) over the five-year period, with Ce and La making the largest contribution. The actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m 3 . Coal combustion source displayed a downward trend. Ingestion was the main exposure pathway for REEs in PM 2.5 for both children and adults. Ce contributed the most to the total intake of REEs in PM 2.5 among the population, followed by La and Nd. The exposure risks of REEs in PM 2.5 in the region were relatively low, but the trend of change was of great concern. It was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Gaseous mercury pollution control technologies with low stability and high releasing risks always face with great challenges. Herein, we developed one halloysite nanotubes (HNTs)-supported tungsten diselenide (WSe 2 ) composite (WSe 2 /HNTs) by one-pot solvothermal approach, curing Hg 0 from complicated flue gas (CFG) and reducing second environment risks. WSe 2 as a monolayer with nano-flower structure and HNTs with rod shapes in the as-prepared sorbent exhibited outstanding synergy efficiency, resulting in exceptional performance for Hg 0 removal with high capture capacity of 30.6 mg·g -1 and rate of 9.09 μg·g -1 ·min -1 , which benefited from the high affinity of selenium and mercury (1 ×10 45 ) and the adequate exposure of Se-terminated. The adsorbent showed beneficial tolerance to high amount of NO x and SO x . An online lab-built thermal decomposition system (TPD-AFS) was employed to explore Hg species on the used-sorbent, finding that the adsorbed-mercury species were principally mercury selenide (HgSe). Density functional theory calculations indicated that the hollow-sites were the major adsorption sites and exhibited excellent selectivity for Hg 0 , as well as HgSe generation needed to overcome the 0.32 eV energy barrier. The adsorbed mercury displayed high environmental stability after the leaching toxicity test, which significantly decreased its secondary environmental risks. With these advantages, WSe 2 /HNTs possess enormous potential to achieve the effective and permanent immobilization of gaseous mercury from CFG in the future., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Antimony (Sb) in PM 2.5 has attracted close attention as a new air pollutant due to its extensive use in daily life. The identification of antimony sources in PM 2.5 by scientific methods is important to control its pollution. In this study, the Sb and other elements concentrations and Pb isotopic compositions in PM 2.5 and possible pollution sources (soil, road dust, traffic emission, coal-fired fly ash, local factory emission dust and cement dust) were analyzed. The results showed that the Sb in the PM 2.5 samples had seasonal change. The enrichment factors of Sb in PM 2.5 samples were all above 100 in four seasons, which indicated anthropogenic pollution. The average value of potential ecological risk index was at extremely high-risk level greater than 320. Based on Pearson correlation coefficient and hierarchical cluster analysis results, the pollution sources of antimony and lead in PM 2.5 samples were highly consistent which means that Pb isotopes might be a new and feasible tracer for Sb pollution in air. The sources analysis results based on Pb isotopes indicated that the proportion of Pb and Sb from coal-fired fly ash was the highest in winter (47.7%) and inclined to road dust in spring (34.5%), but it was mainly from traffic emissions in summer and autumn (34.2% and 32.8%). This study showed that Pb isotope tracing can be applied to predict the potential pollution sources, and it was also a feasible substitute for tracing Sb pollution in PM 2.5 ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A water-stable bimetallic Fe/Zr metal-organic framework [UiO-66(Fe/Zr)] for exceptional decontamination of arsenic in water was fabricated through a facile one-step strategy. The batch adsorption experiments revealed the excellent performances with ultrafast adsorption kinetics due to the synergistic effects of two functional centers and large surface area (498.33 m 2 /g). The absorption capacity of UiO-66(Fe/Zr) for arsenate [As(V)] and arsenite [As(III)] reached as high as 204.1 mg/g and 101.7 mg/g, respectively. Langmuir model was suitable to describe the adsorption behaviors of arsenic on UiO-66(Fe/Zr). The fast kinetics (adsorption equilibrium in 30 min, 10 mg/L As) and pseudo-second-order model implied the strong chemisorption between arsenic ions and UiO-66(Fe/Zr), which was further confirmed by DFT theoretical calculations. The results of FT-IR, XPS analysis and TCLP test demonstrated that arsenic was immobilized on the surface of UiO-66(Fe/Zr) through Fe/Zr-O-As bonds, and the leaching rates of the adsorbed As(III) and As(V) from the spent adsorbent were only 5.6% and 1.4%, respectively. UiO-66(Fe/Zr) can be regenerated for five cycles without obvious removal efficiency decrease. The original arsenic (1.0 mg/L) in lake and tap water was effectively removed in 2.0 hr [99.0% of As(III) and 99.8% of As(V)]. The bimetallic UiO-66(Fe/Zr) has great potentials in water deep purification of arsenic with fast kinetics and high capacity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Along with the environmental protection policies becoming strict in China, the air pollution control devices (especially selective catalytic reduction (SCR)) are widely equipped in coal-fired power plants. The installation and run of these devices will inevitably affect mercury (Hg) species distribution in coal fired by-products such like fly ash (FA) and gypsum. In this work, a new on-line coupling system based on atomic fluorescence spectrometry (AFS) with a home-made chromatographic workstation was successfully developed to identify Hg species through thermal programmed desorption (TPD). The influences of matrix, furnace temperature, and carrier gas flow on analytical performance were investigated and the parameters were optimized. The FA and gypsum samples from coal-fired power plants equipped with SCR were collected and the mercury species were analyzed by the developed coupling system. HgCl 2 and HgO were the main species in FA, while Hg 2 Cl 2 and HgO were the main species in gypsum. All of Hg species in the studied FA and gypsum samples were released below 400 °C. A sequential extraction procedure was applied to further verify the operational Hg species including mobile and non-mobile fractions in FA and gypsum samples. This study demonstrated that AFS coupled with TPD procedure was an effective method to analyze Hg species in coal combustion by-products from power plants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This work aims at exploring a novel environment-friendly nanomaterial based on natural clay minerals for arsenic removal in aqueous samples. Halloysite nanotubes (HNTs) were selected as the substrate with Mn oxides loaded on the surface to enhance its arsenic adsorption ability and then grafted onto the SiO 2 -coated Fe 3 O 4 microsphere to get a just enough magnetic performance facilitating the material's post-treatment. The prepared composite (Fe 3 O 4 @SiO 2 @Mn-HNTs) was extensively characterized by various instruments including Fourier transform infrared spectroscope (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TG), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscope (XPS), and X-ray diffraction (XRD). Batch experiments were carried out to get the optimum test conditions for arsenic adsorption by the composite, including pH, loading amount of Mn oxides, adsorbent dosage, and the co-existing ions. The adsorption of As III and As V on Fe 3 O 4 @SiO 2 @Mn-HNTs were both well fitted with the pseudo-second-order kinetic model as well as the Langmuir adsorption isotherm model revealing the chemisorption between arsenic and Fe 3 O 4 @SiO 2 @Mn-HNTs. The adsorption process of As III and As V were both endothermic and spontaneous displayed by the thermodynamic study. The capacities of the prepared composite are 3.28 mg g -1 for As III and 3.52 mg g -1 for As V , respectively, which are comparable or better than those of many reported materials in the references. Toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) tests were carried out to access the secondary environmental risk of the composite and showed that it was quite environmentally stable and can be safely disposed. The composite was successfully applied in environmental water samples indicating its great potential applicability in future., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Binary metallic organic frameworks can always play excellent functions for pollutants removal. One binary MOFs, UiO-66(Fe/Zr)), was newly synthesized and applied to remove aquatic selenite (SeIV) and selenate (SeVI). The adsorption behaviors and mechanisms were investigated using batch experiments, spectroscopic analyses, and theoretical calculations (DFT). The characterization results showed that the material inherited the topological structure of UiO-66 and excellent thermal stability. The large specific surface area (467.52 m 2 /g) and uniform mesoporous structures of the synthesized MOFs resulted in fast adsorption efficiency and high adsorption capacity for selenium species. The adsorbent kept high adsorption efficiency in a wide pH range from 2 to 11 with good anti-interference ability. The maximum adsorption capacity for Se(IV) and Se(VI) reached as high as 196 mg/g at pH 3 and 258 mg/g at pH 5, respectively. The process was conformed to fit pseudo-second-order kinetics and Langmuir isotherm, and could be explained by the formation of Fe/Zr-O-Se bond on the material surface, which was interpreted by the results of XPS, FTIR and DFT calculation. The regeneration and TCLP experiments demonstrated that UiO-66(Fe/Zr) could be regenerated for five cycles without obvious decrease of efficiencies, and the leaching rate of the adsorbed Se(IV) and Se(VI) in the spent adsorbent were only 4.8% and 2.3%. More than 99% of original Se(IV) and Se(VI) in the lake and tap water samples (1.0 mg/L of Se) could be removed in 2.0 h., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The creation of an environmentally friendly synthesis method for silver nanomaterials (AgNPs) is an urgent concern for sustainable nanotechnology development. In the present study, a novel straightforward and green method for the preparation of silver nanoparticle/reduced graphene oxide (AgNP/rGO) composites was successfully developed through the combination of phytosynthesis, continuous flow synthesis and microwave-assistance. Oriental persimmon (Diospyros kaki Thunb.) extracts were used as both plant reducing and capping agents for fast online synthesis of AgNP/rGO composites. The experimental parameters were optimized and the morphologies of the prepared materials were investigated. The characterization results reveal that spherical AgNPs were quickly synthesized and uniformly dispersed on rGO sheets using the proposed online system. Fourier transform infrared spectroscopy analysis confirmed that phenols, flavonoids, and other substances in the plant extracts played a decisive role in the synthesis of AgNP/rGO composites. Using sodium borohydride (NaBH 4 ) degradation of p-nitrophenol (4-NP) as a model, the catalytic activity of the prepared AgNP/rGO materials was evaluated. The complete degradation of 4-NP was achieved within 12 min through the use of AgNP/rGO materials, and the composite had a much better catalytic activity than the bare AgNPs and rGO had. Compared with the conventional chemical method, our online method is facile, fast, cost-efficient, and environmentally friendly., (Copyright © 2021. Published by Elsevier B.V.)

Gaseous arsenic emitted from coal combustion flue gas (CCFG) causes not only severe contamination of the environment but also the failure of selective catalytic reduction (SCR) catalysts in power plants. Development of inexpensive and effective adsorbents or techniques for the removal of arsenic from high-temperature CCFG is crucial. In this study, halloysite nanotubes (HNTs) at low price were modified with CuCl 2 (CuCl 2 -HNTs) through ultrasound assistance and applied for capturing As 2 O 3 (g) in simulated flue gas (SFG). Experiments on arsenic adsorption performance, adsorption mechanism, and adsorption energy based on density functional theory were performed. Modification with CuCl 2 clearly enhanced the arsenic uptake capacity (approximately 12.3 mg/g) at 600 °C for SFG. The adsorbent exhibited favorable tolerance to high concentrations of NO x and SO x . The As 2 O 3 (III) was oxidized and transformed into As 2 O 5 (V) on the CuCl 2 -HNTs. The Al-O bridge had the highest adsorption energy for the O end of the As-O group (-2.986 eV), and the combination formed between arsenic-containing groups and aluminum was stable. In addition, the captured arsenic could be stabilized in the sorbent at high temperature, making it possible to use the sorbent before the SCR system. This demonstrates that CuCl 2 -HNTs is a promising sorbent for arsenic oxidation and removal from CCFG.

Metal-organic frameworks (MOFs) have been widely applied for pollutants removal in water. However, the powdered MOFs are always suffered from aggregation during use and difficult collection after use. These problems discount their efficiency and inhibit their reusability. In this work, Zr-based MOF (UiO-66) was successfully imprisoned into a water-stable polyacrylonitrile (PAN) substrate by electrospinning. The containing UiO-66 hybrid membrane was confirmed by instrumental characterizations and its stability was also investigated by ICP-OES analysis. The obtained composite membrane can efficiently remove both arsenite (AsIII) and arsenate (AsV) from water under natural pH conditions. The adsorption kinetic fitted well with pseudo-second-order model and was dominated by chemisorption. Its adsorption isotherm can be described by Langmuir model. The maximal adsorption capacities of the hybrid membrane for As(V) and As(III) were 42.17 mg/g and 32.90 mg/g, respectively. Our results demonstrated that the MOFs-dispersed electrospun nanofiber membrane can greatly inherit the MOFs' original adsorption properties and exhibits good regenerability without loss of MOFs. Electrospinning is an effective and practical method for the preparation of MOFs hybrid membrane, which makes the composite very easy to be collected after use., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

The distribution and chemical speciation of arsenic (As) in different sized atmospheric particulate matters (PMs), including total suspended particles (TSP), PM 10 , and PM 2.5 , collected from Baoding, China were analyzed. The average total mass concentrations of As in TSP, PM 10 , and PM 2.5 were 31.5, 35.3, and 54.1 µg/g, respectively, with an order of PM 2.5 >PM 10 > TSP, revealing that As is prone to accumulate on fine particles. Due to the divergent toxicities of different As species, speciation analysis of As in PMs is further conducted. Most of previous studies mainly focused on inorganic arsenite (iAs III ), inorganic arsenate (iAs V ), monomethylarsonate (MMA), and dimethylarsinate (DMA) in PMs, while the identification and sensitive quantification of trimethylarsine oxide (TMAO) were rarely reported. In this study, a high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry system was optimized for As speciation including TMAO in PMs. An anion exchange column was used to separate MMA, DMA and iAs V , while a cation exchange column to separate TMAO and iAs III . Results showed that iAs V was the dominate component in all the samples, corresponding to a portion of 79.2% ± 9.3% of the total extractable species, while iAs III , TMAO and DMA made up the remaining 21%. Our study demonstrated that iAs III accounted for about 14.4% ± 11.4% of the total extracted species, with an average concentration of 1.7 ± 1.6 ng/m 3 . It is worth noting that TMAO was widely present in the samples (84 out of 97 samples), which supported the assumption that TMAO was ubiquitous in atmospheric particles., (Copyright © 2021. Published by Elsevier B.V.)

Halloysite nanotubes (HNTs) as a natural and inexpensive clay mineral with hollow nanotubular structures, good biocompatibility and active surfaces have been ubiquitously applied in many fields. In this work, a novel multifunctional core-shell sorbent based on HNTs, CuCl 2 -HNTs encapsulated magnetic microspheres (SiO 2 @Fe 3 O 4 ), was successfully fabricated and applied for Hg 0 removal from flue gas with good performance for the first time. The core-shell structure prevented the composites from aggregating but kept their magnetism, which enabled the adsorbents being easily separated for reuse by an external magnetic field. In addition, the special structure also significantly enhanced the adsorption capacity of the composites by dispersing the CuCl 2 modified HNTs on the prepared magnetic microspheres. The adsorption performance was comprehensively investigated and fitted by dynamic models. The adsorption followed surface adsorption, particle diffusion and chemisorption with very good SO 2 tolerance. The Cu + , Cl - and lattice oxygen were the crucial components for Hg 0 removal. In order to further understand the possible mechanism, an online home-made coupling system of temperature-programmed decomposition (TPD) was used to investigate the mercury species on the spent adsorbent in addition to X-ray photoelectron spectroscopy analysis. The results confirmed the mercury species adsorbed were primarily Hg 0 , HgO and HgCl 2 ., (Copyright © 2020. Published by Elsevier B.V.)

High-efficient and economic sorbents are highly desired for arsenic (As) emission control in flue gas from coal-fired power plant. A series of Fe-Mn binary oxides were prepared by a facile method, and their behaviors for gaseous arsenic removal in flue gas were investigated. The binary oxide exhibited a remarkable synergistic effect for arsenic removal compared with Mn or Fe monometallic oxide. The possible effects of CO 2 , NO, SO 2 , and O 2 on the removal performance were also studied. The adsorption ability was excellent and stable in simulated flue gas conditions. X-ray photoelectron spectroscopy (XPS) and high-performance liquid chromatography atomic fluorescence spectroscopy (HPLC-AFS) coupling system were applied to analyze the species of surface-adsorbed arsenicals and soluble arsenicals. It was confirmed that the good sorption performance resulted from oxidation of As 2 O 3 (As(III)) to As 2 O 5 (As(V)) by Mn oxide and followed by efficient adsorption of As(V) on Fe oxide. Considering the toxicity of pentavalent arsenicals is lower than trivalent arsenicals, the oxidation of arsenic compounds can not only enhance its removal capacity but also decrease the toxicity of arsenicals after capture., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

It is very necessary to produce bio-activated carbon for special use with easy procedure and low cost. One kind of huge surface area microporous bio-material was successfully prepared from agricultural residues (peanut shell, Arachis hypogaea Linn.) and beneficially applied to control elemental mercury (Hg 0 ) in simulated coal-fired flue gas in this study. The possible effects of experimental factors including activator, reaction temperature, and flue components were investigated. The physicochemical properties of the prepared adsorbents were characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM-EDX), and X-ray photoelectron spectroscopy (XPS). The results indicated that the peanut shell activated carbon presented excellent Hg 0 removal efficiency near 90% at 150 °C. The characterization analysis indicated that the removal characteristics were governed by both physical adsorption and chemical adsorption. The chemisorbed mercury on the activated carbon was mainly distinguished into mercuric chloride (HgCl 2 ) and mercuric oxide (HgO). The presence of C-Cl and O* promoted Hg 0 into HgCl 2 and HgO. Zinc chloride could not only improve the micropore quantity of activated carbon but also have remarkably positive effects on the elemental mercury removal. This study provided a practical and easy preparation method of bio-activated carbon for Hg 0 removal with low cost. Graphical Abstract.

Coal-Gas replacement project has been implemented to decrease haze pollution in China in recent years. Airborne arsenic (As) mostly originates from coal burning processes. It is noteworthy to compare the distribution of arsenic fraction in PM 2.5 before and after coal-gas replacement. Eighty PM 2.5 samples were collected in Baoding in December 2016 (coal dominated year) and December 2017 (gas dominated year) at different functional areas including residential area (RA), industrial area (IA), suburb (SB), roadside (ST) and Botanical Garden Park (BG). The fraction, bioavailability and health risk of As in the PM 2.5 samples were investigated and compared between these two years. Arsenic was mainly distributed in the non-specifically sorbed fraction (F1) and the residual fraction (F5). However, the proportion of F1 to the total As in 2017 was higher than that in 2016, while the proportion of As in the amorphous and poorly-crystalline hydrous oxides of Fe and Al fraction (F3) in 2017 was lower. The distributions of fraction and bioavailability showed temporal and spatial characteristics. The total concentration and bioavailability of As in SB and IA were significantly higher than those in RA, ST and BG. The BF (Bioavailability Factor) values of As ranged from 0.30 to 0.61. Health risk assessment indicated that the hazard quotient (HQ) and carcinogenic risk (CR) of As in PM 2.5 significantly decreased after coal-gas replacement., Competing Interests: Declaration of competing interest All authors (Jiao-Jiao Xie, Chun-Gang Yuan, Jin Xie, Xiao-Dong Niu, Xu-Rui Zhang, Ke-Gang Zhang, Pei-Yao Xu, Xiao-Ying Ma, Xiang-Bin Lv) have seen and approved the submission of the manuscript. The authors declared that there is no conflict of intrest. We also affirm that this manuscript is not under consideration for publication and has not been published elsewhere in any medium including electronic journals and computer databases of a public nature. We assure you that there are no related works that are currently under consideration for publication in this or other journals., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Fractions, bioavailability, health risks of fine particulate maters (PM 2.5 )-bound potentially toxic elements (PTEs) (Pb, Cd, Cr, Cu and Zn) were investigated before and after coal limiting in Baoding city. The winter PM 2.5 samples were collected at different functional areas such as residential area (RA), industrial area (IA), suburb (SB), street (ST) and Botanical Garden Park (BG) in 2016 (coal dominated year) and 2017 (gas dominated year). The fractions and bioavailability of PTEs were determined and evaluated based on BCR sequential extraction. Health risks through inhalation exposure were evaluated by US EPA health risk assessment model. The results from different years and functional areas were compared and discussed. The fractions and bioavailability of PM 2.5 -bound PTEs varied with functional areas. The percentages of cadmium (Cd) and zinc (Zn) in acid-soluble fraction (F1-Cd and F1-Zn) to the total amount of Cd and Zn were low in BG samples (p < 0.05). Bioavailability of Cd were high in SB samples (p < 0.05). Total contents of PM-bound PTEs in 2017 generally decreased compared with 2016. The differences of fraction and bioavailability between 2016 and 2017 depended on the elements and areas. Higher proportions of copper (Cu) in acid-soluble fraction (F1-Cu) and bioavailability of Cu (p < 0.05) were found in 2017 samples. Significant differences were found just at IA and RA for Pb, Cd and Zn. Our results indicated that the health risks from inhalation exposure for PTEs in PM 2.5 declined about 11%-52% after the coal limiting in this city., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Sequential extraction has been validated as an effective method to assess the fractions of elements in fly ash. However, the time consumption and high labor costs limit the application of the conventional sequential extraction (CSE) for fast screening of elemental fractions in fly ash. In this study, two ultrasound-assisted sequential extraction (UASE) methods were developed for fast analysis of arsenic (As) and selenium (Se) fractions in fly ash (FA). The parameters of UASE were optimized by comparing the results of As and Se obtained from UASE with those values observed via CSE. The operation time of sequential extraction procedures for As and Se were shortened from 24.5 h to less than 90 min. A certified reference material (CRM, GBW08401) and real fly ash samples were applied to validate the developed UASE. The recoveries of As and Se were found in the range of 82.3% to 114%. For all fractions, the performance of UASE was faster than CSE with the acceptable uncertainties. The analytical results demonstrated that the concentration of As in F3 was found to be higher than other fractions, while the main forms of Se were found to be in F1 and F3 in the fly ash samples. Based on the advantages of high efficiency and easy operation, the developed UASE procedures can be applied for fast screening of the mobility and bioavailability of As and Se in FA from coal fired power plants., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Huge amounts of fly ash (FA) can be annually produced in power plants. Fly ash always contains high levels of arsenic (As) and selenium (Se) due to the preconcentration of these two elements during coal combustion process. It would be much concerned to screen their fractions and potential environmental behaviors in fly ash for beneficial use and treatment. Fast and practical methods for this purpose are urgently needed. Two fast and effective microwave-assisted sequential extraction schemes (MASE) were developed for fast screening As and Se fractions in fly ash for the first time. The extraction parameters including microwave irradiation time, temperature and power energy were optimized by comparing the results from MASE and the conventional scheme (Wenzel method). The results indicate that the extraction efficiency of As and Se in various fractions can be significantly accelerated by microwave irradiation. The whole procedure operation time can be significantly reduced from 24.5 h to 44 min by microwave assistance compared with the conventional shaking schemes. The recoveries of As and Se in the various extracted fractions were all above 80% with relative standard deviations (RSDs) below 8%. The developed methods were further confirmed by the validation of the certified reference material GBW08401 and fly ash samples from six power plants. The developed MASE methods are practical and effective for fast screening arsenic and selenium fractions in fly ash samples., (Copyright © 2019. Published by Elsevier Inc.)

The sequential extraction method was used to determine the fraction of arsenic (As) in different-sized particulate matters (PMs) (i.e., PM 2.5 , PM 10 , and total suspended particles (TSP)). Samples were collected from Baoding, a typical medium-sized city with the serious haze pollution in China. The bioavailabilities of As in the samples were estimated based on the fraction results. A large percentage of fine particles were detected in TSP, with the average PM 2.5 /PM 10 and PM 10 /TSP ratios all above 0.69. The total concentrations of As in PM 2.5 , PM 10 , and TSP samples were in the range of 4.5-296.4, 14.1-708.0, and 32.8-798.0 ng m -3 , respectively. The mass percentages of As in PM 2.5 , PM 2.5-10 , and PM 10-100 were calculated; the results indicated that As tended to concentrate in fine particles. PM-bound As mainly presented in the nonspecifically sorbed fraction (F1) during all of the sampling periods. The percentages of F1-As and bioavailability of As were higher in PM 2.5 , followed by PM 10 and TSP. By contrast, the residual fraction (F5-As) contents declined in the order of TSP > PM 10 > PM 2.5 . Significant differences in the speciation and bioavailability of As in different-sized PMs were found, and the influence of particle size on the speciation and bioavailability of As in PMs was verified. Fine particles adsorbed more As with higher bioavailability, and potentially led to more serious adverse effects on human health than the larger ones.

The health risks and toxicity of heavy metals (HMs) in PM 2.5 are not only associated with their total amounts, but also with their species and bioaccessibility. In this study, the speciation (fractions) and bioaccessibility of HMs (Pb, Cd, Cr, Cu and Zn) as well as their correlations in fine particulate matter (PM 2.5 ) samples from four seasons were studied. A sequential extraction procedure was applied to divide the studied HMs into four fractions: acid-soluble fraction (F1), reducible fraction (F2), oxidative fraction (F3) and residual fraction (F4). The simulated body fluids (gastrointestinal and lung phases) were used for in vitro tests in order to evaluate the bioaccessibility of HMs. The distribution of HMs in PM 2.5 was season and element dependent. It was found that Zn was the most abundant element among the five measured metals and followed by Pb, Cu, Cr and Cd. The total contents of each HM in different seasons were in the following order: winter > autumn > spring > summer. The studied HMs were mainly concentrated in acid-soluble fraction (F1) with high bioaccessibility (p < 0.05) except for Cr. Zn, Pb and Cu possessed the highest bioaccessibility in summer while Cd and Cr were the highest in winter. In vitro tests indicated that HMs in PM 2.5 were much more accessible to gastrointestinal fluids rather than lung phase (Gamble's solution). A significant correlation was found between the results from the optimized BCR sequential extraction and solubility bioaccessibility research consortium (SBRC). The fractions extracted by SBRC were consistent with the first two fractions extracted by the sequential extraction method., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The distribution and bioavailability of arsenic (As) in indoor/outdoor total suspended particulates (TSP), inhalable particulate matters (PM 10 ), and fine particulate matters (PM 2.5 ) in Baoding, China were investigated. The average I/O ratios for TSP, PM 10 , and PM 2.5 were 0.52, 0.66, and 0.96, respectively. There was no significant correlation between indoor/outdoor TSP, PM 10 , and PM 2.5 . The indoor/outdoor concentrations of As surpassed the limited value of As. I/O ratios of arsenic in TSP, PM 10 , and PM 2.5 were 0.52, 0.58, and 0.55, respectively. The contents of arsenic in different fractions were mainly affected by the total concentrations of arsenic in particulate matters (PM) rather than the particle sizes for TSP and PM 10 . Arsenic was mainly in non-specifically sorbed fraction (F1) in both indoor and outdoor PM 2.5 . The evaluated carcinogenic risk (CR) was within the safe level. The bioavailability of As increased with particle size decreasing for both indoor and outdoor PM. The potential bioavailability of As in outdoor particles was higher than that of indoor particles with the same size, especially PM 2.5 .

Arsenic (As) can be easily enriched in atmospheric particulate matters (PMs), especially in fine particulate matters (PM 2.5 ). In this study, thirty two PM 2.5 samples were collected in four seasons in Baoding, China, where the haze pollution was very serious in recent years. The total contents, species and bioavailability of arsenic in PM 2.5 samples were investigated. Species of arsenic in the PM 2.5 samples were discriminated as five fractions using a sequential extraction method: non-specifically sorbed fraction (F1), specifically-sorbed fraction (F2), amorphous and poorly-crystalline hydrous oxides of Fe and Al fraction (F3), well-crystallized hydrous oxides of Fe and Al fraction (F4) and residual fraction (F5). Bioavailabilities of arsenic in the PM 2.5 samples were evaluated by in vitro tests using both solubility bioavailability research consortium (SBRC) and Gamble's solution extraction methods. The total volume concentrations of As in PM 2.5 were significantly higher in winter than the other seasons. However, the highest mass concentration of As was found in spring. Scanning electron microscopy (SEM) characterization indicated that the physical morphology of the particles varied in different seasons. Significant differences of fraction distribution and BFs were found between different seasons. Arsenic in PM 2.5 samples mainly presented in F1 with high bioavailability factor (BF), especially for the samples in summer. In vitro tests indicated that arsenic in PM 2.5 could be dissolved more easily in gastric phase rather than intestinal and lung phases. There was a significant correlation between species and in vitro tests. Interestingly, a synergy effect was found between F2 and F3. Health risk assessment indicated that arsenic in PM 2.5 via inhalation exposure for both children and adults could cause adverse effects. Principal component analysis suggested that the arsenic in PM 2.5 was from the similar sources between summer and autumn, winter and spring, respectively., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The aqueous extract of Chinese winter jujube ( Ziziphus jujuba Mill. cv . Dongzao) was used as reducing and capping agents for the synthesis of silver nanoparticles (AgNPs) for the first time. The resulting AgNPs were characterised by UV/Visible (UV-Vis) spectroscopy, atomic force microscope, transmission electron microscopy, selected area electron diffraction, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray and Fourier transform infrared spectroscopy (FTIR). The colloidal solution of AgNPs gave a maximum UV-Vis absorbance at 446 nm. The synthesised nanoparticles were almost in the spherical shapes with an average size of 11.5 ± 4. 8 nm. FTIR spectra were applied to identify the functional groups which were possibly responsible for the conversion of metal ions into nanoparticles. The results showed that the prepared AgNPs were coated with the biomolecules in the extract. The biosynthesised AgNPs showed a remarkable catalytic activity at room temperature, and they also showed good antibacterial properties against Escherichia coli and Staphylococcus aureus .

Arsenic trioxide (ATO) is used as a chemotherapeutic agent for the treatment of acute promyelocytic leukemia. However, increasing drug resistance is reducing its efficacy. Therefore, a better understanding of ATO resistance mechanism is required. In this study, we established an ATO-resistant human epidermoid carcinoma cell line, KB/ATO, from its parental KB-3-1 cells. In addition to ATO, KB/ATO cells also exhibited cross-resistance to other anticancer drugs such as cisplatin, antimony potassium tartrate, and 6-mercaptopurine. The arsenic accumulation in KB/ATO cells was significantly lower than that in KB-3-1 cells. Further analysis indicated that neither application of P-glycoprotein inhibitor, breast cancer resistant protein (BCRP) inhibitor, or multidrug resistance protein 1 (MRP1) inhibitor could eliminate ATO resistance. We found that the expression level of ABCB6 was increased in KB/ATO cells. In conclusion, ABCB6 could be an important factor for ATO resistance in KB/ATO cells. The ABCB6 level may serve as a predictive biomarker for the effectiveness of ATO therapy.

The peel of Citrus maxima ( C. maxima ) is the primary byproducts during the process of fruit or juice in food industries, and it was always considered as biomass waste for further treatments. In this study, the authors reported a simple and eco-friendly method to synthesise gold nanoparticles (AuNPs) using C. maxima peel extract as reducing and capping agents. The synthesised AuNPs were characterised by UV-visible spectrum, X-ray diffraction (XRD), transmission electron microscope (TEM) and Fourier-transform infrared spectroscopy (FTIR). The UV-visible spectrum of the AuNPs colloid showed a characteristic peak at 540 nm. The peaks of XRD analysis at (2 θ ) 38.30°, 44.28°, 64.62°, 77.57° and 81.75° were assigned to (111), (200), (220), (311) and (222) planes of the face-centered cubic (fcc) lattice of gold. The TEM images showed that AuNPs were nearly spherical in shape with the size of 8-25 nm. The FTIR spectrum revealed that some bioactive compounds capped the surface of synthesised AuNPs. The biosynthesised AuNPs performed strong catalytic activity in degradation of 4-nitrophenol to 4-aminophenol and good antibacterial activity against both gram negative ( Escherichia coli ) and gram positive ( Staphylococcus aureus ) bacterium. The synthesis procedure was proved simple, cost effective and environment friendly.

Two Gram-negative, moderately thermophilic, yellow-pigmented, rod-shaped and motile bacterial strains, designated YIM 75003 T and YIM 75004 T , were isolated from sediment samples collected from the Tagejia hot spring in Tibet, western China. The taxonomic affiliation of the two strains was investigated by a polyphasic approach. Pairwise comparison of the 16S rRNA gene sequences showed that strains YIM 75003 T and YIM 75004 T are closely related to Altererythrobacter buctense M0322 T (97.2 and 97.1% respectively), while sharing 99.9% sequence similarity against each other. Optimum growth of the two strains was observed at 37-45 °C, pH 8.0 and in the presence of 1-6% NaCl (w/v). Their predominant respiratory quinone was found to be ubiquinone 10. The major fatty acids in both the strains were identified as summed feature 8 (C 18:1 ω6c and/or C 18:1 ω7c) and summed feature 4 (C 17:1 anteiso B and/or iso I). Their major polar lipid profiles were found to be diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. The DNA G+C contents of strains YIM 75003 T and YIM 75004 T were determined to be 61.3 and 60.1 mol%, respectively. The DNA-DNA hybridization values between strains YIM 75003 T and YIM 75004 T , and between the two strains and their closely related phylogenetic neighbour A. buctense M0322 T (=CGMCC 1.12871 T ) were less than 70%. Based on the morphological and physiological properties, phylogenetic analyses, chemotaxonomic characteristics and DNA-DNA relatedness values, the two strains can be distinguished from each other and from their phylogenetically closely related strain. Strains YIM 75003 T and YIM 75004 T are, therefore, considered to represent two novel species of the genus Altererythrobacter, for which the names Altererythrobacter lauratis sp. nov. (type strain YIM 75003 T  = KCTC 52606 T  = CCTCC AB2016268 T ) and Altererythrobacter palmitatis sp. nov. (type strain YIM 75004 T  = KCTC 52607 T  = CCTCC AB2016270 T ) are proposed.

Two closely related thermophilic bacterial strains, designated YIM 73013T and YIM 73008, were isolated from a sediment sample collected from a hot spring in Tibet, western Tibet province, China. The taxonomic positions of the two isolates were investigated using a polyphasic approach. The novel isolates were Gram-stain-negative, aerobic, short-rod-shaped and motile by means of a polar flagellum. They were oxidase- and catalase-positive and were able to grow at 30-55 °C (optimum, 37-45 °C), at pH 6.0-8.0 (optimum, pH 7.0) and with NaCl tolerance up to 1 % (w/v). Phylogenetic analyses based on 16S rRNA gene sequences showed that strains YIM 73013T and YIM 73008 formed a distinct lineage with respect to closely related genera in the family Comamonadaceae and shared highest 16S rRNA gene sequences similarities with Acidovorax caeni R-24608T (96.3 and 96.4 %, respectively). The respiratory quinone was ubiquinone-8 (Q-8) and the major cellular fatty acids observed were C17 : 1ω6c, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The genomic DNA G+C contents of strains YIM 73013T and YIM 73008 were 68.7 and 68.3 mol%, respectively. Based on the morphological, phylogenetic and chemotaxonomic results, the two isolates represent a novel species in a new genus, for which the name Tibeticola sediminis gen. nov., sp. nov. is proposed. The type strain of Tibeticola sediminis is YIM 73013T (=DSM 101684T=KCTC 42873T).

A novel Gram-staining-negative, short rod, non-motile, non-spore-forming, aerobic bacterium, designated strain YIM M12096T, was isolated from deep-sea sediment collected from the Indian Ocean. Optimal growth conditions of the strain were observed at 25-30 °C, pH 6.0 and in the presence of 3-5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM M12096T was closely related to Nitratireductor indicus C115T (97.4 % 16S rRNA gene sequence similarity) and Mesorhizobium thiogangeticum SJTT (97.3 %). The strain, however, formed a robust clade with members of the genus Mesorhizobium in phylogenetic dendrograms generated with neighbour-joining, maximum-likelihood and maximum-parsimony trees. Analysis based on the sequence of housekeeping gene recA also gave a similar phylogenetic relationship, indicating that strain YIM M12096T is a member of the genus Mesorhizobium. DNA-DNA relatedness values between strain YIM M12096T and related type strains N. indicus CCTCC AB209298T and M. thiogangeticum DSM 17097T were 40.5 % and 36.7 %, respectively. Chemotaxonomic features of the isolate included phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminophospholipid and an unidentified phospholipid as its characteristic polar lipids and Q-10 as respiratory ubiquinone. Major fatty acids (>10 %) detected were C18 : 1ω7c and/or C18 : 1ω6c, 11-methyl-C18 : 1ω7c and cyclo-C19 : 0ω8c. Based on the chemotaxonomic properties and phylogenetic analyses, strain YIM M12096T is determined to be a member of the genus Mesorhizobium. The strain could be differentiated from the closely related species by the differences in physiological and biochemical properties supported by low DNA-DNA relatedness values. It is therefore concluded that strain YIM M12096T represents a novel species of the genus Mesorhizobium, for which the name Mesorhizobiumsediminum sp. nov. is proposed. The type strain is YIM M12096T (=CCTCC AB 2014219T=KCTC 42205T).

A Gram-stain positive, aerobic, non-motile, asporogenous, coccoid shaped bacterium, designated YIM M12140(T), was isolated from a marine sediment sample collected from the Indian Ocean. Phylogenetic analysis showed that strain YIM M12140(T) forms a separate clade within the family Staphylococcaceae. Strain YIM M12140(T) shares high 16S rRNA gene sequence similarity with Macrococcus brunensis DSM 19358(T) (92.9 %). The isolate was found to grow at 0-10 % (w/v) NaCl (optimum, 2-3 %), pH 6.0-10.0 (optimum, pH 8.0) and temperature 5-40 °C (optimum, 28 °C). The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, one unidentified aminophospholipid and two unidentified polar lipids. The major cellular fatty acids of the strain were identified as anteiso-C15:0, -C17:0, iso-C16:0, anteiso-C19:0 and C20:0. The respiratory menaquinones were found to be MK-6 (94 %) and MK-7 (6 %). The cell wall amino acids were found to contain Lys, Ala, Glu, Gly, Asp, Ser and Thr. Whole cell sugars were identified as mannose, ribose, rhamnose, glucose, galactose and xylose. The G+C content of the genomic DNA of strain YIM M12140(T) was determined to be 42.4 mol %. Based on phenotypic, chemotaxonomic data and phylogenetic analysis, it is proposed that strain YIM M12140(T) represents a novel species of a new genus in the family Staphylococcaceae, for which the name Abyssicoccus albus gen. nov., sp. nov. is proposed. The type strain is YIM M12140(T) (= DSM 29158(T) = CCTCC AB 2014213(T)).

Strain YIM 78300 T , a novel Gram-stain-positive, moderately thermophilic, endospore-forming, rod-shaped, motile bacterium, was recovered from the sediment of a hot spring in the Tagejia Geothermal Field, Angren, Tibet province, western China. Optimum growth was observed at 50-55 °C, at pH 7.0 and with 0-1.5 % (w/v) NaCl. Phylogenetic analysis of the 16S rRNA gene sequence of strain YIM 78300 T indicated that it belongs to the genus Brevibacillus . Similarity levels between the 16S rRNA gene sequences of the new isolate and those of the type strains of Brevibacillus members were 96.9-96.3 %; highest sequence similarity was with Brevibacillus thermoruber DSM 7064 T . The predominant menaquinone was MK-7 and the major cellular fatty acids were iso-C 15 : 0 and iso-C 17 : 0 . The major polar lipids were phosphatidyl- N -methylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two unidentified phospholipids, an unidentified aminophospholipid and two unidentified polar lipids. The G+C content of the genomic DNA of strain YIM 78300 T was 57.9 mol%. Based on phylogenetic analyses, and physiological and biochemical characteristics, strain YIM 78300 T is considered to represent a novel species of the genus Brevibacillus , for which the name Brevibacillus sediminis sp. nov. is proposed. The type strain is YIM 78300 T ( = DSM 29928 T  = CPCC 100738 T ).

A novel Gram-staining positive, catalase-positive, oxidase-negative, aerobic, non-motile coccus, designated strain YIM 13062(T), was isolated from a marine sediment sample collected from the Indian Ocean. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 13062(T) belongs to the genus Kocuria, and is closely related to Kocuria polaris NBRC 103063(T) (97.8 % similarity), Kocuria rosea NBRC 3768(T) (97.6 % similarity) and Kocuria carniphila JCM 14118(T) (97.4 % similarity). The strain grew optimally at 28 °C, pH 8.0 and in the presence of 2-4 % (w/v) NaCl. Cell-wall peptidoglycan type was Lys-Ala3 (type A3α). The major isoprenoid quinones were MK-6(H2) and MK-7(H2). The polar lipids of strain YIM 13062(T) consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), one unidentified phospholipid (PL), one unidentified aminophospholipid (APL), two unidentified aminolipids (AL) and four unidentified lipids (L). Major fatty acids of the novel isolate were anteiso-C15:0, iso-C14:0 and C18:1 2OH. The genomic DNA G+C content of strain YIM 13062(T) was 68.0 mol%. The level of DNA-DNA relatedness between strain YIM 13062(T) and K. polaris NBRC 103063(T), K. rosea NBRC 3768(T), K. carniphila JCM 14118(T) were 53.2, 48.8 and 42.6 %, respectively. On the basis of genotypic and phenotypic data, it is apparent that strain YIM 13062(T) represents a novel species of the genus Kocuria, for which the name Kocuria subflava sp. nov. is proposed. The type strain is YIM 13062(T) (=CGMCC 4.7252(T)=KCTC 39547(T)).

A new ionic current rectification device responsive to a broad range of pH stimuli has been fabricated using porous anodic alumina membrane with tailor-made branching nanochannel array. The asymmetric geometry is achieved by changing oxidation voltage using a simple two-step anodization process. Due to the protonation/deprotonation of the intrinsic hydroxyl groups upon solution pH variation, the nanochannels array-based device is able to regulate ionic current rectification properties. The ion rectification ratio of the device is mainly determined by the branching size and surface charges, which is also confirmed by theoretical simulations. In addition, theoretical simulations show that the slight difference in ion rectification ratio for the nanochannel devices with different branching numbers is due to the propagation of concentration polarization. Three dimensional simulations clearly show the nonuniform concentration profiles in stem nanochannel near the junction interface due to the presence of branching nanochannels. The present ionic device is promising for biosensing, molecular transport and separation, and drug delivery in confined environments.

Two aerobic, Gram-positive actinomycetes, designated YIM 77502(T) and YIM 77510(T), were isolated from geothermally heated soil of Tengchong county, Yunnan province, south-west China. The taxonomic position of strains YIM 77502(T) and YIM 77510(T) were investigated by a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains YIM 77502(T) and YIM 77510(T) belong to the genus Actinomadura. Both strains form extensively-branched substrate and aerial mycelia which differentiated into short spore chains. The cell wall of the two strains contained meso-diaminopimelic acid, while the whole-cell sugars detected were glucose, madurose, mannose and rhamnose. The polar lipid profile of strain YIM 77502(T) was found to consist of diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, two unidentified phospholipids and an unidentified polar lipid, while strain YIM 77510(T) consisted of diphosphatidylglycerol, phosphatidylinositol mannoside and phosphatidylinositol. The respiratory quinones of strains YIM 77502(T) and YIM 77510(T) were MK-9(H6) and MK-9(H8). The major fatty acids (>10 %) of strain YIM 77502(T) were C17:0, iso-C16:0, C17:010-methyl and iso-C18:0, and those of strain YIM 77510(T) were iso-C16:0, C17:010-methyl and iso-C18:0. The G+C contents of strains YIM 77502(T) and YIM 77510(T) were determined to be 71.3 and 70.2 mol%, respectively. The DNA-DNA hybridization values of strains YIM 77502(T), YIM 77510(T) and their closest phylogenetic neighbours Actinomadura echinospora BCRC 12547(T) and Actinomadura umbrina KCTC 9343(T) were less than 70 %. Based on the morphological and physiological properties, and phylogenetic analyses, strains YIM 77502(T) and YIM 77510(T) are considered to represent two novel species of the genus Actinomadura, for which the names Actinomadura amylolytica sp. nov. (type strain YIM 77502(T) = DSM 45822(T) = CCTCC AA 2012024(T)) and Actinomadura cellulosilytica sp. nov. (type strain YIM 77510(T) = DSM 45823(T) = CCTCC AA 2012023(T)) are proposed.

High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs) controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs) developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW), grain length (GL), grain width (GW) and grain thickness (GT) were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng) during five years between 2010-2014 by inclusive composite interval mapping (ICIM) (LOD ≥ 2.5). Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82-23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs.

Background: The incidence of autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, and primary biliary cirrhosis has increased significantly in China. Information about the susceptibility or potential of autoimmune diseases in the general population is lacking., Objective: To explore the prevalence of antinuclear antibody (ANA) and its specificities in the general population in China., Methods: Twenty thousand nine hundred seventy sera samples were taken from the physical examination center in Baoding, China. Indirect immunofluorescence and line immunoassays were used to detect ANA and its specificities, respectively., Results: Samples from females had a higher prevalence of ANA than samples from males (χ(2) = 278.55; P < 0.01). For both sexes, the prevalence of ANA positively correlated with age and there were significant differences among different age groups at 10-year intervals, except the 80 years group (P < 0.05). One thousand two hundred forty-three ANA-positive samples were further analyzed with line immunoassays. There was a significant difference among age groups and between sex groups in terms of the specific autoantibodies (P < 0.01). The autoantibodies with the top-3 positive frequencies were anti-Ro-52, anti-M2, and anti-SSA., Conclusions: There was a high prevalence of ANA positivity in the general Chinese population that seemed to be influenced by sex and age and correlated with specific autoantibodies.

The Donnan potential is successfully isolated from ion pair potential on a ferrocene-labeled polyelectrolyte (DNA) monolayer. The isolated Donnan potential shifts negatively upon the increase in NaClO4 concentration with a slope of -58.8 mV/decade. With the salt concentration grown up to 1 M, the stretched DNA chains in low salt concentration are found to experience a gradual conformation relaxing process. At salt concentrations higher than 2 M, Donnan breakdown occurs where only the ion pair effect modulates the apparent potential. The apparent formal potential also shows strong dependence on solution pH, which reveals that the charge density in the polyelectrolyte monolayer plays an important role in the establishment of Donnan equilibrium.

An online coupling system based on gas chromatography-hydride generation with atomic fluorescence spectrometry (GC-HG-AFS) for the analysis of arsenic species in food seasoning(soy sauce and vinegar) was developed. With absorbent cotton as separation medium, the volatile arsenic species released from the samples were cold trapped online by liquid nitrogen. Then, the baseline separation of the volatile arsenic species was achieved at the room temperature and the arsenic species were sensitively detected by atomic fluorescence spectrophotometer. The experimental conditions such as flow rates of carrier .gas (He), acid type and concentration, reducing reagent concentration and reaction time were discussed. Under the optimum conditions, the limit of detection for As(III), As(V), MMA(V) and DMA(V) was 0.2, 0.2, 0.3 and 0.8 ng x mL(-1), respectively. The recoveries of As(III), As(V), MMA(V) and DMA(V) in soy sauce and vinegar were 93.07%-103.54%. Compared with the traditional liquid chromatography separation algorithm, the method was rapid, sensitive without any complex sample pretreatment. It was suitable and practical for detection of arsenic especially inorganic arsenic in food seasoning.

Background: Several anti-diabetes drugs exert beneficial effects against metabolic syndrome by inhibiting mitochondrial function. Although much progress has been made toward understanding the role of mitochondrial function inhibitors in treating metabolic diseases, the potential effects of these inhibitors on mitochondrial respiratory chain complex III remain unclear., Methods: We investigated the metabolic effects of azoxystrobin (AZOX), a Qo inhibitor of complex III, in a high-fat diet-fed mouse model with insulin resistance in order to elucidate the mechanism by which AZOX improves glucose and lipid metabolism at the metabolic cellular level., Results: Acute administration of AZOX in mice increased the respiratory exchange ratio. Chronic treatment with AZOX reduced body weight and significantly improved glucose tolerance and insulin sensitivity in high-fat diet-fed mice. AZOX treatment resulted in decreased triacylglycerol accumulation and down-regulated the expression of genes involved in liver lipogenesis. AZOX increased glucose uptake in L6 myotubes and 3T3-L1 adipocytes and inhibited de novo lipogenesis in HepG2 cells. The findings indicate that AZOX-mediated alterations to lipid and glucose metabolism may depend on AMP-activated protein kinase (AMPK) signaling., Conclusions: AZOX, a Qo inhibitor of mitochondrial respiratory complex III, exerts whole-body beneficial effects on the regulation of glucose and lipid homeostasis in high-fat diet-fed mice., General Significance: These findings provide evidence that a Qo inhibitor of mitochondrial respiratory complex III could represent a novel approach for the treatment of obesity., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Overactivated microglia contribute to a variety of pathological conditions in the central nervous system. The major goal of the present study is to evaluate the potential suppressing effects of a new type of Ginko biloba extract, GBE50, on activated microglia which causes proinflammatory responses and to explore the underlying molecular mechanisms. Murine BV2 microglia cells, with or without pretreatmentof GBE50 at various concentrations, were activated by incubation with lipopolysaccharide (LPS). A series of biochemical and microscopic assays were performed to measure cell viability, cell morphology, release of tumor necrosis factor- α (TNF- α ) and interleukin-1 β (IL-1 β ), and signal transduction via the p38 MAPK and nuclear factor-kappa B (NF- κ B) p65 pathways. We found that GBE50 pretreatment suppressed LPS-induced morphological changes in BV2 cells. Moreover, GBE50 treatment significantly reduced the release of proinflammatory cytokines, TNF- α and IL-1 β , and inhibited the associated signal transduction through the p38 MAPK and NF- κ B p65 pathways. These results demonstrated the anti-inflammatory effect of GBE50 on LPS-activated BV2 microglia cells, and indicated that GBE50 reduced the LPS-induced proinflammatory TNF- α and IL-1 β release by inhibiting signal transduction through the NF- κ B p65 and p38 MAPK pathways. Our findings reveal, at least in part, the molecular basis underlying the anti-inflammatory effects of GBE50.

Aim: To elucidate the roles of receptor tyrosine kinases RET and VEGFR2 and the RAF/MEK/ERK signaling cascade in cancer treatment with sorafenib., Methods: The cell lines A549, HeLa, and HepG2 were tested. The enzyme activity was examined under cell-free conditions using 384-well microplate assays. Cell proliferation was evaluated using the Invitrogen Alarmar Blue assay. Gene expression was analyzed using the Invitrogen SYBR Green expression assays with a sequence detection system. Protein expression analysis was performed using Western blotting., Results: Sorafenib potently suppressed the activities of cRAF, VEGFR2, and RET with IC(50) values of 20.9, 4 and 0.4 nmol/L, respectively. Sorafenib inhibited cRAF, VEGFR2, and RET via non-ATP-competitive, ATP-competitive and mixed-type modes, respectively. In contrast, sorafenib exerted only moderate cytotoxic effects on the proliferation of the 3 cell lines. The IC(50) values for inhibition of A549, HeLa, and HepG2 cells were 8572, 4163, and 8338 nmol/L, respectively. In the 3 cell lines, sorafenib suppressed the cell proliferation mainly by blocking the MEK/ERK downstream pathway at the posttranscriptional level, which in turn regulated related gene expression via a feed-back mechanism., Conclusion: This study provides novel evidence that protein kinases RET and VEGFR2 play crucial roles in cancer treatment with sorafenib.

Whether a genetic informational nucleic acid is required for the infectivity of transmissible spongiform encephalopathies is central to the debate about the infectious agent. Here we report that an infectious prion formed with bacterially expressed recombinant prion protein plus synthetic polyriboadenylic acid and synthetic phospholipid 1-palmitoyl-2-oleoylphosphatidylglycerol is competent to infect cultured cells and cause prion disease in wild-type mice. Our results show that genetic informational RNA is not required for recombinant prion infectivity.

Oxidative stress has been considered as a major cause of cellular injuries in a variety of clinical abnormalities. One of the plausible ways to prevent the reactive oxygen species (ROS)-mediated cellular injury is dietary or pharmaceutical augmentation of endogenous antioxidant defense capacity. In this study, we investigated the protective actions of citrus flavanones naringin and nobiletin against the cytotoxicity induced by exposure to hydrogen peroxide (H(2)O(2)) (150μM, 3h) in PC12 cells. The results showed that naringin and nobiletin inhibited the decrease of cell viability (MTT reduction), prevented membrane damage (LDH release), scavenged ROS formation, reduced caspase-3 activity, and attenuated the decrease of mitochondrial membrane potential (MMP), respectively, in H(2)O(2)-induced PC12 cells. Meanwhile, naringin and nobiletin increased superoxide dismutase (SOD) and glutathione (GSH) activity, while decreased malondialdehyde (MDA), the production of lipid peroxidation, in H(2)O(2)-induced PC12 cells. In addition, the percentage of cells undergoing H(2)O(2)-induced apoptosis was decreased in the presence of naringin and nobiletin. These results first demonstrate that naringin and nobiletin, even at physiological concentrations, have neuroprotective effects against H(2)O(2)-induced cytotoxicity in PC12 cells. All the above results suggest that these dietary antioxidants are potential candidates for use in the intervention for neurodegenerative diseases., (Copyright 2010 Elsevier Ireland Ltd. All rights reserved.)

A huge amount of coal is always stored in open spaces in coal-fired power plants before combustion. Mercury released from coal by rain or flowing water is an environmental risk and can cause contamination of the soil around the storage area. To better understand mercury pollution and to control mercury emission before combustion, it is necessary to determine the mobility and leaching characteristics of mercury from coal. In this study, we collected ten coal samples from one coal-fired power plant and proposed a sequential extraction procedure to get five fractions of mercury for evaluation. Elemental Hg was found as the most dominant fraction, and sulfate Hg was shown to be the second largest fraction. The mercury in the organic and the soluble fractions were not the major fractions, but they should still be considered because of their high mobility.

The prion hypothesis posits that a misfolded form of prion protein (PrP) is responsible for the infectivity of prion disease. Using recombinant murine PrP purified from Escherichia coli, we created a recombinant prion with the attributes of the pathogenic PrP isoform: aggregated, protease-resistant, and self-perpetuating. After intracerebral injection of the recombinant prion, wild-type mice developed neurological signs in approximately 130 days and reached the terminal stage of disease in approximately 150 days. Characterization of diseased mice revealed classic neuropathology of prion disease, the presence of protease-resistant PrP, and the capability of serially transmitting the disease; these findings confirmed that the mice succumbed to prion disease. Thus, as postulated by the prion hypothesis, the infectivity in mammalian prion disease results from an altered conformation of PrP.

Neural stem cell (NSC) transplantation has the potential to treat neurodegenerative diseases such as Parkinson's disease (PD). In this study, we investigated the effect of transplanted NSCs in a PD animal model. NSCs isolated from the subventricular zone (SVZ) of E14 rats were cultured in vitro to produce neurospheres, which were subsequently infected with recombinant adeno-associated virus (rAAV(2)) expressing enhanced green fluorescent protein (EGFP). The PD animal model was established by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB) of Sprague-Dawley rats. Once the model was established, EGFP-expressing NSCs were transplanted into the substantia nigra pars compacta (SNc) or striatum of PD rats. We found that NSCs transplanted into either site significantly reduced apomorphine-induced circling behavior of PD rats. Pathological analysis revealed that the EGFP-expressing NSCs could be detected at both injection sites at 1, 2 and 4 months after transplantation. SNc transplanted cells dispersed within the SNc with a significant portion differentiated into tyrosine hydroxylase-positive neurons. Whereas cells transplanted into the striatum migrated ventrally and posteriorly towards the SNc. These results suggest that the 6-OHDA damaged brain area attracts grafted NSCs, which migrated from the striatum and survived for a long time in SNc, resulting in behavioral improvement of PD rats.

We describe a sensitive and specific sandwich assay for human alpha-thrombin. The assay takes advantage of sandwich binding of two affinity aptamers for increased specificity, gold nanoparticles for signal amplification, magnetic beads for fast magnetic separation, and inductively coupled plasma mass spectrometry for ultrasensitive detection. Other proteins, such as immunoglobulin G, serum albumin, transferrin, fibrinogen, and lysozyme did not show interference with the assay for human alpha-thrombin. The detection limit of human alpha-thrombin was as low as 0.5 fmol, corresponding to 10 pM thrombin in 50 microL, and the dynamic range covered approximately 3 orders of magnitude.

Using Northern blotting, ISH and FISH, we demonstrated miR-34a expresses with aging in the brain of rhesus monkey and rat. Correspondingly, the same trend was found in the primary cultures of cortical neurons. Moreover, we found that induction of miR-34a led to neuronal apoptosis by targeting BCL-2. Our study suggests that miR-34a may play critical roles in neuronal development and ageing.

For studying the role of CRF in the process of depression, chronic intra-cerebral ventricular administration of CRF in normal rats for 21 days were performed and compared with the depression model of chronic unpredictable miled stress (CUMS) in rats. The Open-field Test and Morris water Maze were employed to test the ability of locomotion and learning and memory. HPLC-UV, RT-PCR were employed to analyze the level of blood serum cortisol and the expression of CRF as well as its receptors (R1 and R2) of CUMS models. After chronic stress, the locomotion activity and spatial learning and memory ability decreased obviously, while the level of serum cortisol increased evidently, and the CRF and its receptor-1 mRNA levels were higher compared with those in normal rats. The rats with chronic administration of CRF also consistently decreased the weight gain, locomotion activity and the ability of spatial learning and memory as the CUMS model. This work demonstrates that CRF plays a very important role in the depression genesis and development, sustained elevation of CRF induced by stress may be the chief factor for depression.