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Ru-doped Co9S8 hollow porous polyhedrons (Ru–Co9S8 HPPs) derived from zeolitic-imidazolate-frameworks were synthesized through hydrothermal coprecipitation and thermal decomposition methods. The results indicate that Ru–Co9S8-500 HPPs possess a strong Ru–Co synergistic effect, large electrochemical surface area, and sufficient active sites, endowing them with excellent hydrogen evolution reaction performance. [ABSTRACT FROM AUTHOR]

The association between gallstone disease and coronary artery atherosclerotic disease (CAD) remains unclear. To clarify their relationship, patients with CAD newly diagnosed by coronary angiography were investigated in this cross-sectional study.The study cohort consisted of 1,270 patients undergoing coronary angiography for the first time between January 2007 and September 2011. Patients with ≥50% diameter stenosis in any major coronary artery on coronary angiography were defined as being CAD positive (n = 766) and those with no stenosis as CAD negative (n = 504). Multivariate logistic regression was used to investigate the relationship between gallstone disease and CAD. The odds ratios (OR) of factors associated with CAD were calculated. In addition, CAD-positive and CAD-negative patients were matched one-to-one by age, gender and metabolic syndrome (MetS), and the association between gallbladder disease and CAD was determined.The prevalence of gallstone disease was significantly higher in CAD-positive than in CAD negative patients (149/766 [19.5%] vs 57/504 [11.3%], P

MicroRNA (MiRNA) plays a crucial role in biological cells to enable assessment of a cancer's development stage. Increasing evidence has shown that the accurate and sensitive detection of miRNA holds the key toward correct disease diagnosis. However, some characteristics of miRNAs, such as their short chains, low concentration, and similar sequences, make it difficult to detect miRNA in biological samples. Nanomaterials usually have good optical, electronic, and mechanical properties and therefore provide new possibilities for improving the performance of miRNA assays. Many different sorts of nanomaterials, including metal nanomaterials, carbon nanomaterials, quantum dots, and transition-metal dichalcogenides, have been used to construct optical and electrochemical assays for miRNA and have shown attractive results. This review describes recent efforts in the application of nanomaterials as sensing elements in electrochemical and optical miRNA assays. The analytical figures of merit of various methods for the detection of miRNA are compared in the present article. The current capabilities, limitations, and future challenges in miRNA detection and analysis based on nanomaterials are also addressed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Se doping MWCNTs-graphene hybrids are prepared and used for supporting substrate. • Y-shaped DNA-aided target recycling signal amplification and hemin/G-quadruplex is used for signal amplification. • The biosensor used for PDGF-BB detection shows linear range of 0.1 pM-10 nM and detection limit of 27 fM. Abstract A highly sensitive electrochemical biosensor for detection of platelet-derived growth factor-BB (PDGF-BB) is developed by using Se-doped multi-walled carbon nanotubes (MWCNTs)-graphene hybrids as electrode supporting substrate, hemin/G-quadruplex as trace labels and Y-shaped DNA-aided target recycling as signal magnifier. The aptamer-containing hairpin probes were first immobilized on the electrode. When target PDGF-BB was added, the aptamer binded PDGF-BB to trigger catalytic assembly of two other hairpins to form many G-quadruplex Y-junction DNA structures, which released PDGF-BB to again bind the intact aptamer to initiate another assembly cycle. G-quadruplex/hemin complexes were produced when hemin was added to generate substantially amplified current output. The developed assay showed a linear range toward PDGF-BB from 0.1 pM to 10 nM with a detection limit of 27 fM (S/N = 3). The method showed excellent specificity and repeatability, and could be expediently applied for sensitive detection of other molecules by simply changing the aptamers. [ABSTRACT FROM AUTHOR]

In this work, a sandwich-type electrochemical biosensing platform is developed based on carbon sphere-MoS 2 (CS-MoS 2 ) and target recycling amplification of catalyzed hairpin assembly (CHA) strategy for ultrasensitive determination of microRNA (miRNA). The CS-MoS 2 is prepared and used as sensing substrate, which shows high specific surface area, enhanced stability and good dispersibility. The capture probe is first modified on Au nanoparticles/CS-MoS 2 modified glassy carbon electrode through Au-S band, and hairpin DNA1 (H1) then reacts with it and unfolds its loop domain by hybridizing with target miRNA-21. The opened H1 subsequently assembles with biotin labeled hairpin DNA 2 (H2) to displace the target. The liberated miRNA-21 is free and backs to the original solution to proceed next circulation, resulting in the generation of large amounts of H1–H2 duplex. Massive signal indicators horseradish peroxidase are then immobilized on electrode, and catalyze hydrogenperoxide + hydroquinone (H 2 O 2  + HQ) system to produce a strong electrochemical response. The proposed assay benefits from advantages of sandwich-type structure, favorable electrochemical properties of CS-MoS 2 and CHA target recycling amplification strategy. Therefore, it exhibits a wide linear relation between 1 × 10 −16 and 1 × 10 −10  M with a low detection limit of 1.6 × 10 −17  M for miRNA-21 detection. [ABSTRACT FROM AUTHOR]

In this work, we report an ultrasensitive electrochemical biosensor for microRNA-21 (miRNA-21) detection by using a competitive RNA–RNA hybridization configuration. A biotinylated miRNA of the self-same sequence with the target miRNA is mixed with the samples, and allowed competition with the target miRNA for a thiolated RNA probe immobilized onto a tungsten diselenide (WSe2) nanosheet modified electrode. Thereafter the current response is obtained by forming the hybridized biotinylated miRNA with streptavidin–horseradish peroxidase (HRP) conjugates to catalyze the H2O2 + hydroquinone (HQ) system. Benefiting from the high specific surface area of WSe2 nanosheets, the competitive hybridization configuration and the signal amplification of the H2O2 + HQ detection system, the proposed assay exhibits a wide linear range of 0.0001–100 pM towards target miRNA with a detection limit of 0.06 fM (S/N = 3), and shows excellent discrimination ability for base-mismatched miRNA sequences. Therefore, the designed platform has promising prospects for the detection of miRNA in biomedical research and early clinical diagnosis. [ABSTRACT FROM AUTHOR]

A 2-dimensional tungsten disulfide–acetylene black (WS2–AB) composite is synthesized by a simple hydrothermal method to achieve excellent electrochemical properties for applications as a DNA biosensor. The biosensor is fabricated based on the Au nanoparticles (AuNPs) and WS2–AB composite modified electrode, which subsequently is used to couple with a capture probe by an Au–S bond, then modified with target DNA, auxiliary DNA and bio-H1–bio-H2 (H1–H2) to perform hybridization chain reaction for signal amplification. Herein, two DNA hairpins H1 and H2 are opened by the recognition probe. The nicked double helices from hybridization chain reaction are used to immobilize horseradish peroxidase enzymes via biotin–avidin reaction, which produces signal-amplification detection of target DNA through the catalytic reaction of the hydrogenperoxide + hydroquinone system. Under optimum conditions, the as-prepared biosensor shows a good linear relationship between the current value and logarithm of the target DNA concentration ranging from 0.001 pM to 100 pM and a detection limit as low as 0.12 fM. Moreover, the fabricated biosensor exhibits good selectivity to differentiate the one-base mismatched DNA sequence. This work will open a pathway for ultrasensitive detection of other biorecognition events and gene-related diseases based on layered WS2–AB and hybridization chain reaction. [ABSTRACT FROM AUTHOR]

A research was done to study the Pb adsorption by the root cell wall of tea plant extracted from Longjing 43. It was indicated that the amount of Pb adsorbed by the root cell wall increased with augment of the initial pH of the solution under acidic condition, dramatically as the pH ranged from 2. 0 to 4. 5. The amount of Pb increased with the Pb concentration in the solution at pH 4. 5, which could be well fitted by the Freundlich adsorption model. The adsorbed Pb reached 9.7 mg ∙ g-1 under equilibrium condition, 90% of which was adsorbed in 320 minutes, while 50% was desorbed in 60 minutes based on the desorption dynamic curve. The kinetics of both adsorption and desorption could be well described by a second-order rate equation. The amount of absorbed Pb by the root cell wall varied after modified treatments, reducing by 51. 1% after esterifing, 41. 3% with pectinase, and 10. 8% via aminomethylation, suggesting that carboxyl, galacturonic acid, pectin and amino, to some extent, all took part in the Pb adsorption by the root cell wall. [ABSTRACT FROM AUTHOR]

Background: Fatty liver index (FLI) was recently established to predict non-alcoholic fatty liver disease (NAFLD) in general population, which is known to be associated with coronary artery atherosclerotic disease (CAD).This study aims to investigate whether FLI correlates with NAFLD and with newly diagnosed CAD in a special Chinese population who underwent coronary angiography.Methods: Patients with CAD (n = 231) and without CAD (n = 482) as confirmed by coronary angiography were included. Among them, 574 patients underwent B-ultrosonography were divided into NAFLD group (n = 209) and non-NAFLD group (n = 365). Correlation between FLI and NAFLD was analyzed using pearson's correlation. The associations between FLI and NAFLD as well as CAD were assessed using logistic regression. The predictive accuracy of FLI for NAFLD was evaluated using receiver operating characteristics (ROC) curve analysis.Results: FLI was significantly higher in NAFLD group (37.10 ± 1.95) than in non-NAFLD group (17.70 ± 1.04), P < 0.01. FLI correlated with NAFLD (r = 0.372, P < 0.001). The algorithm for FLI had a ROC-AUC of 0.721 (95% CI: 0.678-0.764) in the prediction of NAFLD. Logistic regression analysis showed that FLI was associated with NAFLD (adjusted OR = 1.038, 95% CI: 1.029-1.047, P < 0.01). The proportion of patients with CAD did not differ among the groups of FLI ≤ 30 (32.3%), 30-60 (31.0%), and ≥60 (35.3%). No significant association was found between FLI and CAD (adjusted OR = 0.992, 95% CI: 0.981-1.003 in men and OR = 0.987, 95% CI: 0.963-1.012 in women, P > 0.05).Conclusions: FLI showed good correlation with NAFLD in patients who underwent coronary angiography, but not with newly diagnosed CAD. This might be underestimated because some patients in non-CAD group may have other underlying cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are the typical persistent organic pollutants (POPs) in the environment. As a ubiquitous attenuation course of chlorinated organic compounds in anoxic environment, the microorganism-mediated reductive dechlorination process plays an important role in PCBs transformation, especially the transformation of higher chlorinated PCBs. The higher chlorinated PCBs can be dechlorinated in anaerobic condition, and thus, their persistence and toxicity can be decreased. The resultant lower chlorinated PCBs from the dechlorination can be further degraded and completely mineralized in aerobic condition. This paper summarized the research advances of PCBs microbial reductive dechlorination, introduced the mechanisms and characteristics of the dechlorination and the related specific microorganisms, and approached the affecting factors of PCBs bio-dechlorination, as well as the significances of anaerobic dechlorination coupling with aerobic degradation. The future research directions, including the complex metabolic networks of dechlorinating microbial populations, the screening of novel specific dechlorinators and their practical applications in the remediation of PCBs contaminated sites were also prospected. [ABSTRACT FROM AUTHOR]

Persistent organic pollutants have increasingly become a critical environmental concern, while thermophiles have the high potential of degrading various kinds of environmental organic pollutants. At high temperatures, thermophiles have higher metabolic activity, and the competition by mesophiles is reduced, meanwhile, the solubility and bioavailability of some persistent organic pollutants are greatly increased, and thus, the degradation of the pollutants by thermophiles is more rapid and complete. Therefore, thermophils are of great significance for the bio?treatment of organic wastewater and the bioremediation of organic pollutants?contaminated sites. This paper introduced the research progress on the degradation of organic pollutants by thermophiles in terms of the characteristics of thermophiles in degrading organic pollutants, the effects of temperature on the degradation, the degradation pathways, the degradation enzymes, their coding genes, and practical engineering applications. The future research directions including the degradation mechanisms of thermophiles, their resources reserve, related technology strategies and their applications were also prospected. [ABSTRACT FROM AUTHOR]

Soil microbial indicator is one of the important biological indicators in evaluating the extent of soil contamination. In recent years, with the development of molecular biology, many studies have focused on the ecological functions of soil microorganisms by using metagenomics, metatranscriptome and metaproteomics. Relative to metagenomics and metatranscriptome, soil metaproteomics aims to investigate the spatial and temporal changes of the proteins extracted from soil as well as the functional components of soil microbial genomic expression products, which is more conclusive to explore the ecological functions of soil microbes and their roles in soil pollutants transportation and transformation. Therefore, soil metaproteomics has great potential in soil pollution assessment. Currently, soil metaproteomics is still at its infancy stage, while soil protein extraction method is one of the key factors restraining the potential application of soil metaproteomics. In this paper, the advantages and disadvantage of soil metaproteomics in soil pollution assessment were reviewed, with the focus on the comparison of different soil protein extraction methods. In combining with case studies, the feasibility and limits of soil proteins as an indicator for soil pollution assessment were analyzed. In addition, the future research perspectives on the development of soil metaproteomics were discussed. [ABSTRACT FROM AUTHOR]

Activated sludge process is widely used in treating a wide variety of wastewater, but the by-product is the large amount of excess sludge. To treat the excess sludge properly could spend 25%-60% of the total cost of wastewater treatment, while improperly treating the sludge could cause serious secondary pollution. Therefore, the reduction of excess sludge is becoming a rising challenge. Using thermophiles to degrade excess sludge is a way easy in operation and inexpensive in maintenance, being a promising method in application. This paper reviewed the recent progress in the researches of sludge-degrading thermophiles, their working mechanisms, and the enzymes from thermophiles, such as thermophilic proteolytic enzymes and thermophilic lipases which play an important role in the degradation of sludge. The factors affecting the degradation of sludge by thermophiles were summarized, and the perspectives for the further research on the application of thermophiles in digesting sludge were discussed. [ABSTRACT FROM AUTHOR]

Anammox (anaerobic ammonium oxidation) is an important process of nitrogen cycle, with great potential for the practical use in removing nitrogen from the wastewater containing high concentration ammonium. However, the presence of high concentration organic carbon source is considered unfavorable to anammox. Coupling anammox and denitrification under the presence of organic carbon source could be a useful technique for removing both nitrogen and carbon. This pa- per reviewed the mechanisms of anammox-denitrification coupling process, functional microbial groups, initiation of the coupling process and its control, and related environmental affecting factors. The future research prospects and potential applications of anammox-denitrification coupling process in wastewater treatment were discussed. [ABSTRACT FROM AUTHOR]

Solid state phosphorous is an important phosphorus speciation controlling the phosphorous bioavailability and mobility in the environment. Synchrotron-based X-ray absorption near-edge structure ( XANES) spectroscopy, with its unique advantage of being a non-destructive method in identifying the local chemical information of target element at molecular level in situ, has become one of the frontier technologies for characterizing the speciation of chemical substances and clarifying the microscopic mechanisms of chemical reactions, attracting extensive attention in the field of environmental chemistry. This paper briefly introduced the basic theory of phosphorus XANES spectroscopy , summarized the applications of XANES spectroscopy in the researches of solid state phosphorus speciation in minerals, soils, and organic fertilizers, and analyzed the challenges and prospects of the applications of XANES spectroscopy in identifying the solid state phosphorus speciation in the environmental samples. It was pointed out that XANES spectroscopy should combine with other microscopic spectroscopic techniques and macroscopic analytical methods, complementing each other, to provide a comprehensive and effective technical support for the research of the speciation characterization and transformation mechanisms of phosphorus in the environment. [ABSTRACT FROM AUTHOR]

In conventional wastewater bio-treatment, little attention has been paid on the bio-degradation of grease, causing low efficiency in the process, and thereby, further study should be made on the development and application of related mature and effective bio-treatment techniques. This paper summarized the pathways and mechanisms of grease bio-degradation in wastewater treatment, with the focus on the research progress in the functional microbes involved in lipid hydrolysis and long-chain fatty acid degradation, and briefly introduced a series of new treatment technologies based on the habitat differences of the functional microbes. The key breakthrough directions in the technological study of grease bio-degradation were prospected, expecting to provide theoretical guidance to the development of the related technologies. [ABSTRACT FROM AUTHOR]

A hydroponics experiment combined with subcellular fractionation and sequential extraction was conducted to study the Pb concentration in different organs of two tea plant varieties (Longjing 43 and Yingshuang) and the Pb subcellular distribution and chemical forms in the roots of the varieties. Under Pb stress, the root system of the two varieties had different features in morphology. With the increasing concentration of Pb in culture solution, the Pb concentration in Longjing 43 young leaves increased, but that in Yingshuang爷s had no significant variation. A marked difference was observed in the Pb subcellular distribution and its chemical forms in roots between the two varieties under Pb stress. In Longjing 43 roots, all subcellular fractions except soluble ones had a lower Pb concentration at low Pb stress, and all the subcellular fractions except cell wall ones had a higher Pb concentration at higher Pb stress, compared with those in Yingshuang爷s. In Longjing 43 roots, the HAc鄄extractable Pb occupied the greatest proportion, followed by NaCl鄄extractable Pb, HCl鄄and H2O鄄extractable Pb, and ethanol鄄extractable Pb; while in Yingshuang爷s, NaCl鄄extractable Pb had the greatest proportion, followed by HAc鄄extractable Pb, HCl鄄and H2O鄄extractable Pb, and ethanol鄄extractable Pb. Based on these findings, tea plant variety Yingshuang was likely to possess a higher tolerance to Pb than Longjing 43 did. [ABSTRACT FROM AUTHOR]

Taking non-transgenic parental rice as the control, and by using 13C pulse-chase labeling method coupled with phospholipid fatty acid (PLFA) analysis, this paper studied the effects of transgenic Bt rice on the here soil. The results showed that in the rhizosphere soils of transgenic Bt rice and its non-transgenic parent, saturated PLFAs and branched PLFAs were the main, followed by monounsaturated PLFAs, and polyunsaturated PLFAs. A significantly lower amount of Gram-positive bacterial PLFAs and a higher amount of Gram-negative bacterial PLFAs were observed in the rhizosphere soil of transgenic Bt rice at its seedling, booting, and heading stages, as compared with the control. In the whole growth ?period of rice, transgenic Bt gene had no significant effects on the fungal and actinomycete PLFAs in rhizosphere soil, and no significant difference was observed in the rhizosphere soil 13C-PLFA content between transgenic Bt rice and its non-transgenic parent. These findings indicated that the insertion of exogenous cry1Ab gene into rice only had temporary effects on the microbial community composition in the rhizosphere soil of rice. [ABSTRACT FROM AUTHOR]

In-situ ammonium removal from municipal solid waste (MSW) landfill is an attractive method due to its economic advantages. In this study, two simulated MSW bioreactors with different degrees of initial bio-stabilization were utilized to investigate the effects of intermittent aeration mode and the addition of activated sludge on the removal of ammonium. The results showed that up to 90% of ammonium could be removed and the amount of NOx—N produced was less than 1% of NH4+-N removed in both reactors. The pH values increased rapidly and finally arrived at a high level of 8.5—8.8. The efficiency of ammonium removal was improved by increasing the continuous aeration time, but it was not affected by the addition of activated sludge. A portion of liquid escaped from the reactors in the form of vapour, and as high as 195—258 mg L—1 of NH4 +-N was detected in the vapour collector. According to calculation, nitrification was inhibited by the high level of free ammonia in the bioreactors. As a result, air stripping was enhanced and became the primary pathway of ammonium removal. Therefore, controlling free ammonia concentration was essential in ammonium removal from the aerated MSW bioreactor. [ABSTRACT FROM AUTHOR]

Abstract: The current trend of global warming is expected to stimulate the expansion of harmful cyanobacteria blooms. Previously, the occidental type of barley straw has been used to control blooms in Europe and America, but very little is known about the antialgal abilities of its oriental relative. We tested the use of Tibetan hulless barley straw – the progenitor of oriental barley – to inhibit the growth of cyanobacterium Microcystis aeruginosa. Flow cytometry allowed assessment at single-cell level, with morphologic parameters (cell volume, cell membrane integrity) and physiological parameters (in vivo Chlorophyll a fluorescence, metabolic activity) used as endpoints. The reduction of cell densities together with integrated cell membranes suggests that Tibetan barley may act as an algistatic agent. Doses from 2.0 to 8.0gL−1 of Tibetan barley straw efficiently inhibited the alga, but these doses were much higher than those of occidental barley. Such a large dosage introduced additional nutrients, which stimulated the intracellular metabolic activity and induced two physiological subpopulations in the acute term. After mid and long-term exposure, the growth inhibition effect exceeded the stimulation effect, so that the cells’ metabolic activity and Chlorophyll a fluorescence decayed, simultaneously with shrinkage in the algal cell volume. [ABSTRACT FROM AUTHOR]

Persisters are a group of special subpopulation of bacteria, only occupying <0-1% of the whole population but having the characteristics different from the ordinary bacteria and resistant mutants. They have complex formation mechanism, and are difficult to isolate and culture. The persisters can adapt to the adverse environment via "dormancy-growth-proliferation-to maintain their survival and cell structure stability, and play a vital role in the multi-drug and multi-metal tolerance of microbial biofilm, being of great significance in maintaining the stability of microbial community structure. This paper reviewed the research progress on the characteristics of persisters, their gene regulation mechanisms, and their effects on the multi-drug and multi-metal tolerance of microbial biofilm. The related research directions in the future were also prospected. [ABSTRACT FROM AUTHOR]

Phosphorus (P) release from sediments is one of the most important causes of lake eutrophication, while the activity of P is determined by P chemical form. Due to its advantages in improving our knowledge about the P fractions in environmental samples, the 31P nuclear magnetic resonance (31P NMR) technology has received extensive attention. This paper summarized the current studies on the characterization, translocation, and transformation of P fractions in sediments by using this technology, and described the technical principles, classification, analytical procedures, and specific application fields of this technology. At present, the researches of sediment P by using 31P NMR technology were focused on the characterization of different P forms, the effects of microbes on the P translocation and transformation, and the quantitative analysis of different P fractions. The studies on the P-extracting agents and extraction methods were the hot topics as well. The potential issues and research trends about the application of 31P NMR technology in environmental samples were also discussed. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the microbial activity and community structure in a lead-polluted paddy soil under effects of amendment with different concentration sodium thiosulfate. The amendment of the sulfur-containing substrate increased the soil oxidation-reduction potential and respiration rate, promoted the growth of soil sulfur-oxidizing bacteria, and induced some changes in soil microbial community structure. The clone sequencing indicated that the specific bands of soil microbes in sodium thiosulfate treatments had very high similarity to Bateroidetes, Thiobacillus, β-proteobacteria, and Acidobacteria. Significant changes were observed in the contents of soil carbonate- and Fe/Mn oxide- bound Pb after the amendment of sodium thiosulfate. [ABSTRACT FROM AUTHOR]

Laboratory simulation tests were conducted to examine the effects of different washing reagents (distilled water, HCl, H3PO4, oxalic acid, and CaCl2) in extracting the heavy metals from contaminated soils left by a chemical plant. The effects of reagent concentration, reaction time, and washing time on the washing efficiency were investigated, and the form variation of test heavy metals was determined before and after HCl washing. Distilled water, H3PO4, and CaCl2 could remove less than 1% of most heavy metals, and the highest removal rate was only 3.58%; while 2 mol HCl∙L-1could obtain the highest washing efficiency under the optimal conditions, i.e., soil:liquid ratio was 1:3, reaction time was 1 hour, and the soils were washed twice by HCl solution. The removal rates of Cr, Pb, Zn, Cu, and Cd from test soils were 80.75%, 88.69%, 98.00%, 79.33%, and 95.52%, respectively. Among the washing reagents, HCl could effectively remove all forms of heavy metals. [ABSTRACT FROM AUTHOR]

Landfill sites are the major sources of offensive odor in urban public facilities. With the progress of urbanization and the residents' demands for a higher living environment quality, the odor emission from landfill sites has become a severe pollution problem, and the odor control at landfill sites has been one of the research hotspots. This paper summarized the main components and their concentrations of the odor from landfill sites, and expatiated on the research progress in the in-situ control of the odor. The further research directions in in-situ control of the odor from landfill sites were prospected. [ABSTRACT FROM AUTHOR]

To study the oxidative stress and antioxidative response of Cinnamomum camphora seedlings exposed to nitrogen dioxide (NO2) fumigation. Measurements were made up of the growth, chlorophyll content, chlorophyll fluorescence, antioxidant system and lipid peroxidation of one-year-old C. camphora seedlings exposed to NO2 (0.1, 0.5, and 4 μl/L) fumigation in open top chambers over a period of 60 d. After the first 30 d, 0.5 and 4.0 μl/L NO2 showed insignificant effects on the growth of C. camphora seedlings. However, exposure to 0.5 and 4.0 μl/L NO2 for 15 d significantly reduced their chlorophyll content ( P<0.05), enhanced their malondialdehyde (MDA) content and superoxide dismutase (SOD) activity ( P<0.05), and also significantly reduced the maximal quantum yield of PSII in the dark [the ratio of variable fluorescence to maximal fluorescence ( Fv/ Fm)] ( P<0.05). In the latter 30 d, 0.5 μl/L NO2 showed a positive effect on the vitality of the seedlings, which was reflected by a recovery in the ratio of Fv/ Fm and chlorophyll content, and obviously enhanced growth, SOD activity, ascorbate (AsA) content and glutathione reductase (GR) activity ( P<0.05); 4.0 μl/L NO2 then showed a negative effect, indicated by significant reductions in chlorophyll content and the ratio of Fv/ Fm, and inhibited growth ( P<0.05). Conclusion: The results suggest adaptation of C. camphora seedlings to 60-d exposure to 0.1 and 0.5 μl/L NO2, but not to 60-d exposure to 4.0 μl/L NO2. C. camphora seedlings may protect themselves from injury by strengthening their antioxidant system in response to NO2-induced oxidative stress. [ABSTRACT FROM AUTHOR]

Abstract: Composting is an effective methodology for the treatment of organic waste like pig manure (PM) before land application. However, nitrogen loss through NH3 volatilization during the thermophilic phase is one of the major disadvantages of composting. The presence of Cu and Zn in compost arising from pig feed additives is also an issue. In this study the effects of bamboo charcoal (BC) and bamboo vinegar (BV) added to composting piles on nitrogen conservation and immobility of Cu and Zn during PM composting was investigated. Total Kjeldahl nitrogen (TKN) loss and mobility of Cu and Zn decreased with increased BC addition. TKN loss and mobility of Cu and Zn in the treatment with 9% BC at the end of composting significantly decreased by 65%, 35% and 39% respectively, as compared to the control. Addition of BV further decreased TKN loss. After composting, TKN loss in the treatment with 3% BC+0.4% BV was 23% lower than that in the treatment with 9% BC. The final results indicated that by adding BC or BC+BV into PM composting is an effective method to reduce TKN loss and control the mobility of Cu and Zn. [Copyright &y& Elsevier]

Tea waste is an important part of agricultural solid wastes,because of its various sources and huge amount. The heavy metals removal from waste water by tea waste has been paid much attention by the researchers around the world,owing to the adsorption characteristic of tea waste. In this paper,the research advances in the heavy metals removal from aqueous phase by tea waste were summarized from the aspects of affecting factors,adsorption mechanism,pretreatment,desorption,and regeneration,and the prospects were put forward. It was considered that for the industrialized utilization of tea waste absorbents, further researches should be focused on their adsorption mechanism,pretreatment,desorption and regeneration,technological parameters,and aftertreatment. [ABSTRACT FROM AUTHOR]

A 2-month fumigation experiment was conducted with opened top chambers to study the effects of different concentration (0.1, 0.5, and 4.0 microl · L-1) NO2 on the growth and photosynthesis of 1-year Cinnamomum camphora seedlings. Fumigation with 0.1 and 0.5 microl NO2 · L-1 promoted the growth of the seedlings, while with 4.0 microl NO2 · L-1 was in adverse. The diurnal variation of net photosynthetic rate (Pn) presented two-peaks, with an obvious depression in midday. 0.5 microl NO2 · L-1 increased the Pn, the maximum of Pn reached 8.542 micromol CO2 · m-2 s-1; 4.0 microl NO2 · L-1 decreased the Pn in most period of time; while the effect of 0.1 microl NO2 · L-1 varied with time period. Fumigation with 0.5 and 4.0 microl NO2 · L-1 increased the maximal and minimal values of stomatal conductance (Gs) and intercellular CO2 concentration (Ci), while 0.1 microl NO2 · L-1 increased the maximal and minimal values of Ci but decreased the maximal and minimal values of Gs. At the middle and late stages of fumigation, the mean Pn of the seedlings treated with 0.5 microl NO2 · L-1 was significantly higher than that treated with 0.1 and 4 microl NO2 · L-1. At the early stage of fumigation, 0.5 and 4.0 micro NO2 · L-1 significantly decreased the maximal PS II efficiency (Fv/Fm); and at the late stage, 4.0 μNO2 · L-1 still decreased the Fv/Fm significantly. [ABSTRACT FROM AUTHOR]