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Stabilization of waste activated sludge (WAS) is an essential step for the disposal or reuse. In this study, WAS stabilization via electrochemical pretreatment (EPT) at 0-15V was evaluated for simultaneous dewaterability enhancement, pathogen removal and H 2 S mitigation. The mechanism underlying EPT was investigated and discussed based on the changes in the physicochemical (e.g., particle size, zeta potential, hydrophobicity and extracellular polymeric substances) and biological characteristics (i.e. cell morphology, and distribution and percentages of live/dead cells) of WAS with different EPT voltages. The results revealed that EPT disintegrated WAS flocs and disrupted the cell walls leading to a reduction in particle size (by up to 50%), increased release of extracellular and intracellular substances (by up to 4 times) to facilitate WAS stabilization. With EPT at 15V, the capillary suction time of WAS decreased by 42%, and the concentrations of E. coli and indicator pathogens (Salmonella spp. and Streptococcus faecalis) fell by nearly 5 log 10 reaching U.S. EPA hygienization levels. Furthermore, EPT at 12V or higher suppressed the amounts of dissolved sulfide and H 2 S (g) produced from the WAS under anaerobic conditions by over 99%. This study demonstrates the feasibility of EPT for simultaneous WAS dewaterability enhancement, pathogen inactivation and H 2 S mitigation, providing a one-step alternative for sludge stabilization., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Recovering materials with high value and increasing market demand from sewage and/or sludge is becoming more attractive than recovering traditional resources such as nutrients and biogas. Sulfated polysaccharides (SPs) are valuable and scarce raw materials that can only be produced from marine algae and a few types of animal tissues. This study evaluated if SPs are present in activated sludge obtained from saline sewage with a high level of sulfates present. The presence of SPs-containing extracellular polymeric substances (EPS) was confirmed and quantified for both sludge from lab-scale reactors and full-scale plants for the first time. SPs in the sludge of a lab-scale reactor operated under alternating aerobic/anoxic conditions with 500 mg/L sulfate in the influent (which is typical of Hong Kong saline sewage) reached 342.8 ± 0.3% mg/gVSS, and sludge taken from a full-scale saline wastewater treatment plant (WWTP) contained 418.1 ± 0.4% mg/gVSS of SPs. Purity of the extracted SPs was comparable to that of commercial industrial-grade products. Key bioactivities of SPs (i.e. fucoidan, carrageenan and heparin), namely anti-angiogenesis, anticoagulant and antioxidant, were confirmed after extraction and purification. Interestingly, operating conditions had a strong influence on the contents and types of SPs synthesized in sludge as well as its bioactivities. Although the detailed synthetic pathways of SPs in activated sludge remain unclear, the current study has made a first attempt to recover a high-value scarce resource from biological wastewater treatment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Sulfite has been widely employed as a key agent in many industrial processes, leading to a large amount of sulfite-laden wastes generated. Given its antimicrobial function and destructive ability on cell walls, detailed mechanisms for impacts of sulfite on waste activated sludge (WAS) and outcomes of methane production after the sulfite-pretreatment have not been clear so far. In this study, the feasibility of methane production from sulfite pretreated WAS was verified and investigated. Biochemical methane potential tests demonstrated that methane production from WAS after the pretreatment at 800 mg S/L of sulfite (a typical level in sulfite-laden wastes) increased by up to 25%. Kinetic analysis of the test results indicated that sulfite pretreatment increased the sludge hydrolysis rate (k hyd ) by 1.71 times while the ultimate biochemical methane potential (B u ) by 1.20 times. Further study investigated the effects of sulfite on WAS from the macro-scale (i.e. sludge physicochemical properties) to the micro-scale (i.e. bacterial viability, microbial community). Sulfite concentrations of up to 800 mg S/L substantially enhanced WAS disintegration and solubilization, reducing the particle size by up to 39%, boosting substrate release by 87% and improving cell lysis by 43% through the direct destruction of gram-positive microorganisms (e.g., norank_p_Saccharibacteria) in WAS. Adverse impact on anaerobic digestion by introduction of sulfite was not observed in this study, though a long-term evaluation is needed in the future work. Based on the findings of the present study, sulfite-laden by-products or wastes from industrial processes may be co-treated with WAS when overall cost-effectiveness is concerned., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The conversion of food waste (FW) into the sewage system is regarded as a promising method of relieving the burden of solid waste management. However, knowledge about its effects on sewer processes is limited, particularly in terms of biofilm formation and sulfide production. In this study, a gravity sewer system was set up to investigate the effects of the addition of FW on biofilm formation, the sulfate-reducing bacteria (SRB) population, and the sulfide production potential. The sewer biofilm characteristics changed with long-term FW addition, and a greater thickness (by 32%), an increased dry density (by 13%), and more extracellular polymeric substance (by 141%) were observed. The thicker and denser biofilm limited oxygen diffusion, enlarged the anaerobic area in the sewer biofilm, promoted an increase in the SRB population, and enhanced the sulfide production potential in the gravity sewer. Substantial differences in the H 2 S profiles in the biofilm samples with and without the addition of FW were observed via microelectrode analysis. A model-based investigation of sewer biofilm formation with and without the addition of FW was conducted with a dynamic sewer biofilm model to gain further insights into sewer biofilm processes. The results suggest that the addition of FW can promote sulfide production and SRB growth in a sewer biofilm, which can be significantly affected by the ratio of FW to sewage. It is worth further investigations of the impacts of FW addition on the potential sulfide production in pressure sewers., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A magnetic-pH dual responsive drug delivery system was prepared for antibacterial therapy to reduce the side effects on nonpathological cells or tissues. Iron oxide (Fe 3 O 4 ) core was surface-functionalized with silane coupling agents to link β‑cyclodextrin (β-CD) (CDMNP), and a polypseudorotaxanes shell where polyethyleneglycol chains threaded much CD molecules was further prepared on the magnetic Fe 3 O 4 core (CDMNP-PEG-CD) to enhance loading capacity of roxithromycin (ROX). CDMNP-PEG-CD with a hydrodynamic diameter of ~168 nm was cytocompatible, superparamagnetic, magnetic-responsive and stable for 180 min of storage. No significant interaction with serum albumin was shown for the nanocomposites. The in vitro release from ROX-loaded CDMNP-PEG-CD nanocomposites was about 76% of total drug within 30 min at pH 1.0, 1.6-fold of that at pH 7.4 and 2-fold of that at pH 8.0, presenting pH-responsive drug release behaviors. The nanocomposites showed positive antibacterial activity against both E. coli and S. aureus based on an agar diffusion method. The antibacterial activity of the nanocomposites was more sensitive against E. coli than S. aureus, and the inhibition halo against E. coli was 85% more than that of Fe 3 O 4 . CDMNP-PEG-CD nanocomposites allowed for the localization and fast concentration of hydrophobic drugs, providing a broad potential range of therapeutic applications., (Copyright © 2019. Published by Elsevier B.V.)

3D all-solid-state thin film batteries (TFBs) are proposed as an attractive power solution for microelectronics. However, the challenge in fabricating self-supported 3D cathodes constrains the progress in developing 3D TFBs. In this work, 3D LiMn 2 O 4 (LMO) nanowall arrays are directly deposited on conductive substrates by magnetron sputtering via controlling the thin film growth mode. 3D TFBs based on the 3D LMO nanowall arrays and 2D TFBs based on the planar LMO thin films are successfully fabricated using a lithium phosphorous oxynitride (LiPON) electrolyte and Li anode. In comparison, the 3D TFB significantly outperforms the 2D TFB, exhibiting large specific capacity (121 mAh g -1 at 1 C), superior rate capability (83 mAh g -1 at 20 C), and good cycle performance (over 90% capacity retention after 500 cycles). The superior electrochemical performance of the 3D TFB can be attributed to the 3D architecture, which not only greatly increases the cathode/electrolyte interface and shortens the Li + diffusion length, but also effectively enhances the structural stability. Importantly, the vertically aligned nanowall array architecture of the cathode can significantly mitigate disordered LMO formation at the cathode surface compared to the 2D planar thin film, resulting in a greatly reduced interface resistance and improved rate performance., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The quantification of elemental sulfur (S 0 ) is an important part of monitoring and controlling sulfur-involving processes. Existing methods of S 0 detection either require significant time or involve the use of toxic chemicals. We have developed and validated a new method to determine S 0 in environmental samples using calorimeter-ion chromatography (IC), in which S 0 is fully oxidized to sulfur trioxide (SO 3 ) with pure oxygen at 20 atm in a calorimeter. The resulting SO 3 is then absorbed by a sodium bicarbonate (NaHCO 3 ) solution and analyzed using IC. To verify this method, standard samples with various sulfur contents (5-200 mg S), possible interfering substances (SO 4 2- , SO 3 2- , S 2 O 3 2- and S 2- ), and mixed environmental samples were tested and compared. The high correlation of R 2 = 0.999 between the examined and theoretical values was obtained with a high recovery rate of ≥95% and a low relative standard deviation (RSD) of ≤1%. Samples containing at least 25 mg of S 0 were accurately measured (recovery error < 5%). Thiosulfate was identified as the main interfering substance, and pretreatment was needed to eliminate it. This new method is more efficient, cost-effective, easier to operate, and more secure and accurate than existing methods.

Food waste (FW) is a worldwide environmental issue due to its huge production amount. FW separation from municipal solid waste followed by different treatment strategies has been widely accepted. Food waste disposer (FWD) is a promising approach to separate and collect household food waste (HFW), which has been widely applied in many countries. However, the feasibility of FWD application in many countries is still being debated due to the major concerns over the impact of FWD on the wastewater treatment plants. In order to investigate the feasibility of FWD application, FW characterization is a key work to be conducted in advance. Since the FW characteristics largely vary by region, reliable and representative FW characteristics in different countries should be investigated. To provide such information for further studies on FW management for Hong Kong, HFW was collected from Hong Kong typical households over one year and analyzed systemically in this study. The FW composition varied little from place to place or season to season, and the values observed were comparable with results reported from other countries and regions. Based on the reliable HFW characteristics obtained from one-year survey coupled with statistical analysis, simulated HFW for Hong Kong consisting of 50% fruits, 20% vegetables, 20% starchy food and 10% meat was proposed for future studies. On the other hand, the FWD treatment caused more than 50% of the biodegradable organic content in HFW to dissolve. With a ratio of 1 g food waste to 1 L sewage, total solids in the wastewater stream were predicted to increase by 73%, total chemical oxygen demand by 61%, soluble chemical oxygen demand by 110%, nitrogen by 6% and phosphorus by 16%. Theoretically, 22 million m 3 /year of additional methane could be generated if 50% of Hong Kong residential buildings equipped with FWD. That would certainly increase pollutant loading on the wastewater treatment plants, but also energy recovery potential., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Introducing or grafting molecules onto biomaterial surfaces to regulate cell destination via biophysical cues is one of the important steps for biomaterial design in tissue engineering. Understanding how cells feel the substrate makes it easier to learn the mechanism behind cell-material interaction. In this study, on a glass substrate, we constructed poly-phenoxyethyl methacrylate (PHEMA) brushes having different lengths via a surface-induced atom transfer radical polymerization (SI-ATRP) method. FTIR-ATR and XPS tests of the formed polymer brushes indicate that these brushes have characteristic chemical structures of PHEMA; the polymer brush length revealed by the AFM tests increases linearly with reaction time. Cell lines of BMSCs, ATDC5, and human chondrocytes (HC) were cultured on these substrates to evaluate proliferation, adhesion, and differentiation. Our results demonstrated that the cells cultured on the substrates with short PHEMA brushes developed a spread morphology and organized actin fibers as compared to the cells cultured on those with long brushes. Different cell lines showed different responses depending on the PHEMA brush length. Cells cultured on long PHEMA brushes displayed a more rounded shape, higher gene expression of FAK and integrin, and lower gene expression of NCAM and N-cadherin as compared to those, especially ATDC5 cells, cultured on short PHEMA brushes. On PHEMA brushes with a long length, the cell lines express higher cartilage-specific genes including Sox9 and Col2 and GAG in ECM. The results suggest that polymer brushes having different lengths may interfere with the behavior of the cells cultured on them.

Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.

Dissolved organic nitrogen (DON) extracted from Lake Shankou sediments using KCl was isolated into hydrophobic and hydrophilic fractions. The bioavailabilities of the hydrophobic and hydrophilic fractions to three types of bacterial communities collected from sediments, activated sludge and compost products were examined. The DON recoveries obtained by DAX-8 and cation exchange resins treatment were 96.17%±1.58% and 98.14%±0% for the samples obtained from N4 and N14 stations, respectively. After 25 days of incubation at 25°C, most DON (59% to 96%) was degraded. Hydrophilic DON exhibited a higher reduction rate than hydrophobic DON during the growth phase. Untreated wastewater from Changshuihe town was the main degradable DON source to station N4, and 93% of hydrophilic DON and 80% of hydrophobic DON were degraded. Station N14 received a large amount of refractory DON from forest soils and exhibited DON degradation rates of 82% and 71% for the hydrophilic and hydrophobic fractions, respectively. Amino acid contents and fluorescence intensities were also analyzed. Approximately 27% to 74% of amino acids were taken up by day 5, and their concentration gradually increased in the following days due to the decomposition of dissolved proteins. Parallel factor analysis resulted in identification of tryptophan-like proteins, tyrosine-like proteins and FA-like substances. During the growth phase, 40%-51% of the tryptophan-like proteins were taken up by bacteria, and the accumulation of tyrosine-like proteins was attributed to the release of biotic substances. The concentration of the FA-like substances decreased due to microbial decomposition., (Copyright © 2015. Published by Elsevier B.V.)

Arsenic (As) fractions in the sediments of seven lakes from East Plain Ecoregion and six lakes from Yungui Plateau Ecoregion, China, were investigated. Results indicated that the total As concentrations in sediment samples of lakes of the East Plain Lake Ecoregion are higher than those of Yungui Plateau Lake Ecoregion. Residual As is the main fraction in sediment samples of lakes from both ecoregions, followed by reducible As and soluble or oxidizable As. The total As is correlated to oxidizable As and residual As in sediment samples from both lake ecoregions. As distribution in sediment samples of lakes of the East Plain Ecoregion appears to be affected by human activity, while the As origin mainly comes from natural sources in sediment samples of lakes in the Yungui Plateau Ecoregion. The potential ecological risk index and geoaccumulation index values suggest "low to moderate" risk degree and "unpolluted to moderately polluted" for As in the studied lake sediments., (Copyright © 2014. Published by Elsevier B.V.)

The trophic status assessment of lakes in different lake regions may provide important and fundamental information for lake trophic state classification and eutrophication control. In this study, a region-specific lake eutrophication assessment standard was established through a frequency distribution method based on chlorophyll-a concentration. The assessment standards under the oligotrophic state for lakes in the Eastern plain, Yungui Plateau, Northeast Plain and Mountain Mongolia-Xinjiang regions are total phosphorus of 0.068, 0.005, 0.011, 0.005 mg/L; total nitrogen of 1.00, 0.16, 0.37, 0.60 mg/L; Secchi depth of 0.60, 8.00, 1.55, 3.00 m; and COD(Mn) of 2.24, 1.00, 5.11, 4.00 mg/L, respectively. Moreover, a region-specific comprehensive trophic level index was developed to provide an understandable assessment method for the public. The results indicated that the frequency distribution analysis based on chlorophyll-a combined with trophic level index provided a useful metric for the assessment of the lake trophic status. In addition, the difference of eutrophication assessment standards in different lake regions was analyzed, which suggested that the sensitivities of algae to nutrients and the assessment standard of trophic status possessed significant regional differences for the four lake ecoregions. Lake eutrophication assessment standards would contribute to maximizing the effectiveness of future management strategies, to control and minimize lake eutrophication problems.

Establishing the nutrient reference condition (baseline environmental condition) of lakes in an ecoregion is a critical consideration in the development of scientifically defensible aquatic nutrient criteria. Three methods were applied to determine reference conditions in the Eastern plain ecoregion lakes with respect to total phosphorus (TP), total nitrogen (TN), planktonic chlorophyll a (Chl-a) and Secchi depth (SD). The reference condition value for the lakes in the Eastern plain ecoregion by the trisection method is TP of 0.029 mg/L, TN of 0.67 mg/L, Chl-a of 3.92 mg/m3, SD of 0.85 m, and the reference condition range by the lake population distribution approach is TP of 0.014-0.043 mg/L, TN of 0.360-0.785 mg/L, Chl-a of 1.78-4.73 mg/m3, SD of 0.68-1.21 m. Additionally, empirical models were developed for estimating the reference Chl-a concentration and SD successfully for lakes in the Eastern plain ecoregion. Overall, the data suggest that multiple methods can be used to determine reference conditions and that in Eastern plain ecoregion lakes the reference condition corresponds to a mesotrophic status.

In this study, we report for the first time a one-pot approach for the synthesis of new CdSeTeS quaternary-alloyed quantum dots (QDs) in aqueous phase by microwave irradiation. CdCl2 was used as a Cd precursor during synthesis, NaHTe and NaHSe were used as Te and Se precursors and mercaptopropionic acid (MPA) was used as a stabilizer and source of sulfur. A series of quaternary-alloyed QDs of different sizes were prepared. CdSeTeS QDs exhibited a wide emission range from 549 to 709 nm and high quantum yield (QY) up to 57.7 %. Most importantly, the quaternary-alloyed QDs possessed significantly long fluorescence lifetimes > 100 ns as well as excellent photostability. Results of high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX) and powder X-ray diffraction (XRD) spectroscopy showed that the nanocrystals possessed a quaternary alloy structure with good crystallinity. Fluorescence correlation spectroscopy (FCS) showed that QDs possessed good water solubility and monodispersity in aqueous solution. Furthermore, CdSeTeS QDs were modified with alpha-thio-omega-carboxy poly(ethylene glycol) (HS-PEG-COOH) and the modified QDs were linked to anti-epidermal growth factor receptor (EGFR) antibodies. QDs with the EGFR antibodies as labeling probes were successfully applied to targeted imaging for EGFR on the surface of SiHa cervical cancer cells. We believe that CdSeTeS QDs can become useful probes for in vivo targeted imaging and clinical diagnosis., (Copyright © 2012 John Wiley & Sons, Ltd.)

In this paper, we systematically investigated the conjugation of quantum dots (QDs) with certain biomolecules using capillary electrophoresis (CE) and fluorescence correlation spectroscopy (FCS) methods. Commercial QDs and aqueous-synthesized QDs in our lab were used as labeling probes, certain bio-macromolecules, such as proteins, antibodies, and enzymes, were used as mode samples, and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysulfo-succinimide (Sulfo-NHS) were used as linking reagents. We studied the effects of certain factors such as the isoelectric points (pIs) of bio-macromolecules and buffer pH on the bioconjugation of QDs, and found that the pIs of bio-macromolecules played an important role in the conjugation reaction. By the optimization of the buffer pH some proteins with different pIs were efficiently conjugated with QDs using EDC and Sulfo-NHS as linking agents. Furthermore, we on-line investigated the kinetic process of QDs-bioconjugation by FCS and found that the conjugation reaction of QDs with protein was rapid and the reaction process almost completed within 10 min. We also observed that QDs conjugated with proteins were stable for at least 5 days in phosphate buffer. Our work described here will be very helpful for the improvement of the QDs conjugation efficiency in bioapplications., (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Gold nanoparticles (GNPs) are attractive alternative optical probes and good biocompatible materials due to their special physical and chemical properties. However, GNPs have a tendency to aggregate particularly in the presence of high salts and certain biological molecules such as nucleic acids and proteins. How to improve the stability of GNPs and their bioconjugates in aqueous solution is a critical issue in bioapplications. In this study, we first synthesized 17 nm GNPs in aqueous solution and then modified them with six thiol compounds, including glutathione, mercaptopropionic acid (MPA), cysteine, cystamine, dihydrolipoic acid, and thiol-ending polyethylene glycol (PEG-SH), via a Au-S bond. We systematically investigated the effects of the thiol ligands, buffer pH, and salt concentrations of the solutions on the colloidal stability of GNPs using UV-vis absorption spectroscopy. We found that GNPs modified with PEG-SH were the most stable in aqueous solution compared to other thiol compounds. On the basis of the above results, we developed a simple and efficient approach for modification of GNPs using a mixture of PEG-SH and MPA as ligands. These biligand-modified GNPs were facilely conjugated to antibody using 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide and N-hydroxysulfosuccinimide as linkage reagents. We conjugated GNPs to epidermal growth factor receptor antibodies and successfully used the antibody-GNP conjugates as targeting probes for imaging of cancer cells using the illumination of a dark field. Compared to current methods for modification and conjugation of GNPs, our method described here is simple, has a low cost, and has potential applications in bioassays and cancer diagnostics and studies.

In this study, the sediment profiles of total organic carbon, total nitrogen, C/N ratios, total phosphorus, N/P ratios, C/P ratios, particle sizes, and stable carbon and nitrogen isotopes (δ(13)C and δ(15)N) were used to investigate natural and anthropogenic impacts on Lake Chaohu over the past 100 years. Before 1960, Lake Chaohu experienced low productivity and a relatively steady and low nutrient input. The increasing concentration and fluxes of total organic carbon, total nitrogen, total phosphorus, together with changes in the δ(13)C and δ(15)N of organic material in the sediment cores, suggested that the anthropogenic effects on trophic status first started because of an increase in nutrient input caused by a population increase in the drainage area. With the construction of the Chaohu Dam, an increase in the utilization of fertilizer and the population growth which occurred since 1960, stable depositional conditions and increasing nutrient input resulted in a dominantly algae-derived organic matter source and high productivity. Nutrient input increased most significantly around 1980 following the rapidly growing population, with concomitant urbanization, industrial and agricultural development. This study also revealed that the concentration and distribution of nutrients varied between different areas of sediment within Lake Chaohu because of the influence of different drainage basins and pollution sources., (This journal is © The Royal Society of Chemistry 2012)

Recent sediments from Lake Chenghai, China, were investigated at high temporal resolution to trace both natural and anthropogenic effects on the lake using total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), organic phosphorus (Po), inorganic phosphorus (Pi) and organic carbon and nitrogen stable isotopes (delta13Corg and delta15N) in a 137Cs-dated sediment core. The results indicated that the sedimentary record covers the last 60 years, during which the lake had undergone apparent changes in nutrient sources and productivity in response to nutrient loading. Prior to the late 1980s, the nutrient contents in sediments mainly originated from algae and lake productivity was relatively stable. Since the late 1980s, increasing TOC, TN and TP concentrations together with the change of delta13Corg and delta15N suggested anthropogenic perturbations in nutrient loading and lake productivity. Endogenic nutrients derived from algae and anthropogenic inputs were two important sources of sedimentary nutrients. The anthropogenic nutrients mainly originated from the discharge of industrial wastewater and artificial cultivation of Spirulina after the middle 1980s, and domestic wastewater discharged from Yongsheng County since 1993.

This study has worked on the evaluation of the temporal and spatial evolution of heavy metal contamination in sediment taken from a shallow eutrophic lake, Lake Chaohu, China, over the last 100 years, and thereby used (137)Cs and (210)Pb dating, a PIRLA procedure, statistical analysis, geochemical normalization and a enrichment factor calculation (EF). Concentrations of 5174, 29 325, 10.7, 36.4, 20.4, 386.0, 21.1 and 38.4 mg kg(-1) for Ti, Fe, Co, Cr, Cu, Mn, Pb and Zn, respectively, are proposed as natural background values for the Lake Chaohu based on a PIRLA procedure. The contamination history from the last 100 years can be divided into two periods. Before the 1960s, heavy metal contamination did not occur and there was no spatial difference for heavy metal distribution. Since the 1960s, heavy metal enrichment and contamination has occurred, and the west half of the lake region showed a higher degree of contamination than the east half to various intensified anthropogenic activities. In the east half of the lake region, the anthropogenic source of heavy metals mainly originated from agricultural intensification, whereas in the west half of the lake it originated from city runoff and industry as well as agriculture. In all anthropogenic heavy metals, Co is only from industry.

The characteristics of organic phosphorus (P(o)) fractions in the sediments of nine lakes from the middle and lower reaches of the Yangtze River region, Yungui Plateau, Qinghai-Tibet Plateau, Northeast China Region, and Mongolia-Xinjiang Plateau, China were investigated and the differences of the different lakes on P fractionation was discussed. The results indicated that organic matter (OM) showed significant positive correlations with P(o) in sediment samples, and the rank order of the P(o) fractions was: residual P(o) > HCl-P(o) > fulvic acid-P(o) > humic acid-P(o) > NaHCO(3)-P(o) with mean relative proportions 7.4 : 3.4 : 2.4 : 1.7 : 1.0. The labile and moderately labile P(o) were the main fractions in the sediments for shallow eutrophic lakes except for Lake Qilu, however, nonlabile P(o) was dominant in the sediments from deep lakes. Labile P(o) was significantly correlated with total phosphorus (TP), inorganic phosphorus (P(i)), P(o), NaHCO(3)-P(i), HCl-P(i) and NaOH-P(i), and the nonlabile P(o) was significantly and positively related to OM, TP, P(o) and NaOH-P(i).

In this paper, we described a simple approach for aqueous synthesis of highly luminescent ZnSe(S) alloyed quantum dots (QDs) in the presence of 3-mercaptopropionic acid as stabilizers using zinc chloride and NaHSe as precursors. The synthesis conditions were systematically investigated. We observed that the pH value of the Zn precursor solution had significant influence on the optical properties and the structure of the as-prepared ZnSe(S) QDs. The optimal pH value and molar ratio of Zn(2+) to HSe(-) were 12.0 and 25 : 1 respectively. Under the optimal conditions, we prepared highly photoluminescent ZnSe(S) QDs at up to 31% quantum yield (compared with Rhodamine 6G). The characterization of HRTEM and XRD showed that the ZnSe(S) QDs had good monodispersity and nice crystal structure. The fluorescence life time spectra demonstrated that ZnSe(S) QDs had a long lifetime in contrast to fluorescent dyes. Compared with the currently used organometallic approach, our method was 'green', the reaction condition was mild and the as-prepared ZnSe(S) QDs were water-soluble. More importantly, our method was low cost, and was very suitable for large-scale synthesis of highly luminescent ZnSe(S) QDs for the future applications., (Copyright © 2009 John Wiley & Sons, Ltd.)

Objective: To investigate the manifestation, characteristics and treatment of lipoid proteinosis (LP) in larynx., Methods: Sixteen cases of LP with hoarseness as the first sign were reported. The onset was in the newborn period in 10 cases. The upper eyelids were infiltrated in all cases, 13 of them reported an age of onset older than 6 - 8 years. The laryngeal behaviors and its treatment, multisystem manifestations, and characteristics of histopathology were evaluated., Results: One patient had moderate hoarseness, and the others had severe hoarseness. Videolaryngoscopy revealed thickening of the interarytenoid region and irregularities along the rims and the surface of the vocal folds due to yellowish papules. Oral tissues showed yellow-white infiltrates in 13 cases (81.3%). Whitish moniliform papules on the upper eyelids were found in all cases. Pock-like or acneiform scars were particularly evident on the face and the limbs in 14 cases (87.5%). Histologically, it was characterized by deposition of hyaline material in the submucosa and dermis of the eyelid or larynx with periodic acid-Schiff-positive and Congo red stain-negative. Eight patients underwent microlaryngosurgery for the excision of deposits in the vocal folds. The vocal function was significantly improved after surgery., Conclusions: One of the most common features of lipoid proteinosis is hoarseness since infancy with laryngeal involvement. LP patients also display skin or mucosa infiltration of multiple systems. Microlaryngosurgical excision of the deposits in the vocal fold could improve the voice.

John Bowlby refers to attachment as the special affect and trust bond that a child establishes with other emotionally significant people, who constitute a source of security and protection. The main figure of attachment during childhood is generally the person who fulfills the maternal function (primary caregiver), although it is also established with the father, brothers/sisters, grandparents, and others. The approaching behavior could be activated by different stimuli which depends on each person and his/her developing stage. This bond is developed according to experiences and relationships in the first years of life - experiences stored in mental representations (internal working models), which influence the individual's psychic organization. Different instruments allow to make evident the different types of attachment bonds and to establish a correlation between parents and children. The Attachment makes up a valid theoretical and methodological model for the investigation, prevention and treatment in mental health.