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High-grade serous ovarian cancer (HGSOC) accounts for the majority of deaths caused by epithelial ovarian cancer. The specific molecular changes attributable to the pathogenesis of HGSOC are still largely unknown. TRAF4 has been identified to be up-regulated in certain cancers. However, the role and mechanism of TRAF4 in HGSOC remain unclear. In this study, we aim to explore the prognostic value and function of TRAF4 in HGSOC. Immunohistochemical staining and prognostic analysis were used to estimate the prognosis value of TRAF4 in HGSOC. Cell counting assays, colony formation assays, sphere formation assays and tumorigenic assays were used to explore the function of TRAF4 in ovarian cancer cells. Furthermore, RNA-seq, qPCR and western blotting were performed to investigate the molecular mechanism of TRAF4 in ovarian cancer cells. The results showed that TRAF4 was significantly higher expressed in ovarian cancer than normal ovarian epithelium. Moreover, high expression of TRAF4 was significantly associated with shorter overall survival and recurrence-free survival in HGSOC. Knockdown of TRAF4 significantly inhibited the proliferation and tumorigenicity of ovarian cancer cells, whereas overexpression of TRAF4 promoted the proliferation and tumorigenicity of ovarian cancer cells both in vitro and in vivo. Mechanistically, our study demonstrated that TRAF4 expression was positively correlated with the YAP pathway gene signatures, and the malignant progression induced by TRAF4 was inhibited after silencing YAP signaling by its selective inhibitor. In conclusion, our findings suggested that TRAF4 promoted the malignant progression of ovarian cancer cells by activating YAP pathway and might serve as a prognostic biomarker for HGSOC.

Introduction Dye pulsed light (DPL) was proven to be effective at treating erythematous and telangiectatic skin disorders. However, there are limited data on the efficacy of DPL treatment for erythematotelangiectatic rosacea (ETR), and researchers do not fully understand the factors that may affect the efficacy. Here, we performed a study to investigate the efficacy of DPL treatment for ETR and determine the factors affecting that efficacy. Methods Sixty-five patients with ETR underwent three treatment sessions with DPL at 4-week intervals and were followed up at 4 weeks after the last treatment session. Skin type, sex, age, lesion site, severity of erythema and telangiectasia, VISIA percentile ranking, clinical photographs and red area images were recorded at baseline. The post-treatment erythematous and telangiectatic scores and VISIA percentile rankings were recorded, and the effects of different personal and clinical factors on the efficacy were statistically analysed. Results The erythema and telangiectasia scores and VISIA percentile rankings showed significant improvement after the DPL procedures (p 0.05). With regard to telangiectasia, the treatment efficacy was greater for mild telangiectasia than for severe telangiectasia (odds ratio = 4.14, p 0.05). Conclusion DPL is not the optimal procedure for treating severe telangiectasia in patients with ETR, whereas the efficacy of the treatment for erythema was not affected by the severity of the condition.

Objective: The aim of this study was to investigate the relationships between treatment outcomes of patients with urogenital Chlamydia trachomatis infections and minimum inhibitory concentrations (MICs) and drug resistance genes. Methods: The clinical data of 92 patients diagnosed with Chlamydia trachomatis (C. trachomatis) infections were collected. Of these patients, 28 received regular treatment with azithromycin and 64 received minocycline. All patients underwent three monthly follow-ups after the completion of treatment. The microdilution method was used for the in vitro susceptibility tests. The acquisition of 23S rRNA mutations and presence of the tet(M) gene were detected by gene amplification and sequencing. Results: The MICs of azithromycin, clarithromycin, erythromycin, tetracycline, doxycycline, and minocycline were comparable for isolates from the treatment failure and treatment success groups. Higher detection rates of 23S rRNA gene mutations and tet(M) were found in the treatment failure group (57.14% and 71.43%, respectively) than in the treatment success group (14.29% and 30.23%, respectively) (p < 0.05). The A2057G, C2452A, and T2611C gene mutations of 23S rRNA were detected in eight clinical isolates from the azithromycin treatment failure group, while the T2611C gene mutation was detected in one clinical strain from the treatment success group. Conclusions: The detection of resistance genes could better explain the high treatment failure rate than the MIC results in patients with urogenital C. trachomatis infections, highlighting the need for genetic antimicrobial resistance testing in infected patients.

A series of Ru/g-C3N4 materials with highly dispersed Ru were firstly prepared by an ultrasonic impregnation method using carbon nitride as a support. The catalysts were characterized by various techniques including BET and elemental analysis, ICP-AES, XPS, XRD, CO2-TPD and TEM. The results demonstrated that Ru/g-C3N4 materials with a mesoporous structure and highly dispersed Ru were successfully prepared. The chemo-selective hydrogenation of p-phenylenediamine (PPDA) to 1,4-cyclohexanediamine (CHDA) over Ru/g-C3N4 as a model reaction was investigated in detail. PPDA conversion of 100% with a CHDA selectivity of more than 86% could be achieved under mild conditions. It can be inferred that the carbon nitride support possessed abundant basic sites and the Ru/g-C3N4-T catalysts provided suitable basicity for the aromatic ring hydrogenation. Compared to the N-free Ru/C catalyst, the involvement of nitrogen species in Ru/g-C3N4 remarkably improved the catalytic performance. In addition, the recyclability of the catalyst demonstrated that the aggregation of Ru nanoparticles was responsible for the decrease of the catalytic activity. Furthermore, this strategy also could be expanded to the selective hydrogenation of other aromatic diamines to alicyclic diamines.

Background Staphylococcal Scalded Skin Syndrome (SSSS) is caused by a special type of Staphylococcus aureus (S.aureus) which can produce exfoliative toxins. The generalized SSSS is recommended to be admitted and treated with intravenous antibiotics. However, there were limited reports on whether personal and clinical factors can have impacts on the duration of intravenous antibiotic application for pediatric patients with generalized SSSS. We performed a study to assess the factors affecting intravenous antibiotic treatment course of SSSS patients. Additionally, the positive culture rates of S.aureus in different samples and the antibiotic-resistant profile were investigated. Methods Two hundred nineteen patients with generalized SSSS were included. Gender, age, area, season, maximum axillary temperature, white blood cell (WBC) count, C-reactive protein (CRP) level, types of intravenous antibiotics, and types of external antibiotics were recorded as the baseline. Simple linear regression was applied in the univariate analysis to determine the variables with statistical significance and then these variables were further examined in multivariate linear regression model. The positive culture rates of S.aureus in different sample sources were calculated and the drug sensitivity results were statistically compared by pairwise Chi square test. Results According to the multiple linear regression, older ages (β = − 0.01, p p p p p Conclusion Elevated leukocytes and CRP level indicated prolonged intravenous antibiotic treatment course. Older ages and external application of fusidic acid helped to reduce the treatment course. Compared with blood samples, the culture positive rates of S.aureus in periorificial and throat swabs were higher. Oxacillin and vancomycin resistance was rare and clindamycin resistance was common. Clindamycin monotherapy for SSSS should be avoided.

In this study, a typical Zhundong coal sample was examined, and a series of step-wise pyrolysis experiments, where the temperature was gradually elevated in small increments, were carried out by using an entrained-flow bed reactor. In addition, chars from pyrolysis were investigated by X-ray diffraction and Raman spectroscopy with the aim of revealing the microcrystalline parameters and degree of crystallinity, defects, and disorder. Then, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were employed to observe the changes in the chemical surface properties of Zhundong coal before and after pyrolysis. The XRD and Raman spectra indicate that the transition from small aromatic ring systems to large aromatic ring systems in coal with the increase in pyrolysis temperature results in the increase in the lateral size of the basic lattice unit of carbon. Furthermore, condensation and the combination of aromatic rings cause the stacking height of the basic lattice units to first decrease and then increase. When the pyrolysis temperature is lower than 1000 °C, the content of graphite decreases, and the inter-layer spacing of the lattice changes slightly with an increase in temperature. As the pyrolysis temperature continues to rise, the content of graphite increases, the inter-layer spacing of the lattice decreases sharply, reaching a minimum of 0.347 nm at 1500 °C, which represents the degree of increase in the graphitisation of coal char and the transformation of the microcrystalline structure of coal char to that of graphite. FT-IR and XPS analyses show that exchangeable sodium is primarily connected with oxygen functional groups in coal char, and the oxygen functional groups are easily decomposed during coal pyrolysis. Meanwhile, the content of C H/C C/C C groups increases with increasing pyrolysis temperature, while that of C O decreases. As a result, there are more hydrocarbon groups on the surface of the coal char, whereas less oxygen functional groups are exposed to the coal char surface.

A novel approach for the synthesis of epoxybutane via decarboxylation of butenyl carbonate derived from butanediol was developed for the first time. For the carbonylation of butanediol with dimethyl carbonate, NaAlO2 has exhibited excellent catalytic activity under mild reaction conditions. The yield of butenyl carbonate reached as high as 96.2%. NaAlO2 provides suitable acid–base active sites to promote the transesterification reaction of butanediol and dimethyl carbonate. For the following step of decarboxylation of butenyl carbonate, ionic liquid 1-butyl-3-methylimidazolium bromide could effectively catalyze the decarboxylation process both in batch or continuous processes. Moreover, the catalytic mechanism for the crucial step of decarboxylation of butenyl carbonate over 1-butyl-3-methylimidazolium bromide was explored using DFT calculations. The results showed that the electrostatic and hydrogen-bond effects of 1-butyl-3-methylimidazolium bromide played a crucial role for the generation of epoxybutane. Briefly, the Br anion of the ionic liquid attacks the methylene of the ring and the H of the ionic liquid cation attacks the carbonyl oxygen, which facilitated the five-ring opening and subsequent decarboxylation to form BO. This study not only provided a new and green synthetic route for producing epoxybutane, but also contributed to the effective utilization of butanediol, which is inevitably produced as by-product in the process of coal to ethylene glycol, suggesting a promising application in the clean manufacture of epoxybutane with inexpensive cost.

Background: Epithelial ovarian cancer is nowadays one of the malignancies in women, this study aimed to identify novel biomarkers to predict prognosis and immunotherapy efficacy.Methods: The differentially expressed genes (DEGs) obtained from online database Gene Expression Omnibus (GEO)were screened via GEO2R and Venn diagram software, gene enrichment was analysed by Gene Ontology(GO) function and Kyoto Encyclopedia of Genes and Genomes(KEGG), then protein protein interaction(PPI)network and Cytoscape software were used to confirm the genes closely related to ovarian cancer. Survival analysis of hub genes were obtained from Kaplan–Meier plotter, with their differential expression in specimen validated by Gene Expression Profiling Interactive Analysis (GEPIA) and an integrated repository portal for tumor-immune system interactions (TISIDB). Finally, we used the Tumor Immune Estimation Resource 2.0 (TIMER2.0) and application Estimate the Proportion of Immune and Cancer cells (EPIC) to search the immune infiltration characteristics of the genes.Results: 355 DEGs between epithelial ovarian cancer and normal ovarian tissue were screened out. These DEGs were associated with extracellular exosome, bicellular tight junction and cell-cell junction, and remarkably enriched in molecules of cell adhesion and leukocyte transendothelial migration activity. Ten hub genes were identified via protein protein interaction (PPI) network: PTAFR, HLA-DRA, OAS2, OAS3, PTPN6, LYN, VAMP8, IRF6, ITGB2, CD47. Furthermore, the Kaplan–Meier plotter was conducted, overexpression of four genes was positively connected to poor prognosis in ovarian cancer:OAS2, OAS3, ITGB2, CD47,which were also correlated with immune infiltrates in ovarian cancer and had the highest degree of correlation with tumor associated macrophages (TAMs) infiltration, among which ITGB2 was highly correlated with TAMs infiltration level.Conclusion: ITGB2, OAS2, OAS3, and CD47 are upregulated with unfavorable prognosis in ovarian cancer, and ITGB2 may act as a novel prognostic biomarker with immune infiltration values.

BackgroundTumor-infiltrating lymphocytes (TILs) have important roles in predicting tumor therapeutic responses and progression, however, the method of evaluating TILs is complicated. We attempted to explore the association of TILs with clinicopathological characteristics and blood indicators, and to develop nomograms to predict the density of TILs in patients with high-grade serous ovarian cancer (HGSOC).MethodsThe clinical profiles of 197 consecutive postoperative HGSOC patients were retrospectively analyzed. Tumor tissues and matched normal fallopian tubes were immunostained for CD3+, CD8+, and CD4+ T cells on corresponding tissue microarrays and the numbers of TILs were counted using the NIH ImageJ software. The patients were classified into low- or high-density groups for each marker (CD3, CD4, CD8). The associations of the investigated TILs to clinicopathological characteristics and blood indicators were assessed and the related predictors for densities of TILs were used to develop nomograms; which were then further evaluated using the C-index, receiver operating characteristic (ROC) curves and calibration plots.ResultsMenopausal status, estrogen receptor (ER), Ki-67 index, white blood cell (WBC), platelets (PLT), lactate dehydrogenase (LDH), and carbohydrate antigen 153 (CA153) had significant association with densities of tumor-infiltrating CD3+, CD8+, or CD4+ T cells. The calibration curves of the CD3+ (C-index = 0.748), CD8+ (C-index = 0.683) and CD4+ TILs nomogram (C-index = 0.759) demonstrated excellent agreement between predictions and actual observations. ROC curves of internal validation indicated good discrimination for the CD8+ TILs nomogram [area under the curve (AUC) = 0.659, 95% CI 0.582–0.736] and encouraging performance for the CD3+ (AUC= 0.708, 95% CI 0.636–0.781) and CD4+ TILs nomogram (AUC = 0.730, 95% CI 0.659–0.801).ConclusionMenopausal status, ER, Ki-67 index, WBC, PLT, LDH, and CA153 could reflect the densities of T cells in the tumor microenvironment. Novel nomograms are conducive to monitor the immune status of patients with HGSOC and help doctors to formulate the appropriate treatment strategies.

A series of Ru/g-C

A novel approach for the synthesis of epoxybutane

Orpiment is one of the major arsenic sulfide minerals which commonly occurs in the gold mine environment and the weathering of this mineral can lead to the contamination of arsenic. In this study, chemical leaching experiments using 10 g/L Fe3+ at 35 C and 50 degrees C were carried out and the results show that orpiment can be leached by Fe3+ and the leaching rate of orpiment was significantly enhanced in the presence of Ag+. The bioleaching experiments with mesophilic bacteria Acidithiobacillus ferrooxidans and moderate thermophilic bacteria Sulfobacillus sibiricus were carried out, showing that these two strains can survive in the mineral pulp and oxidize Fe2+ to regenerate Fe3+. Based on above results, it is believed that the leaching action of the acidic mining drainage by some bacteria can lead to the release of arsenic from orpiment. Different performances of At. ferrooxidans and S. sibiricus in the tests suggest they follow two different mechanisms and this point of view is further confirmed based on analyses of the composition and morphology of the mineral residue by SEM and EDS. (C) 2014 Elsevier B.V. All rights reserved.

The transformation of alkali and alkaline earth metals (AAEMs) in Zhundong coal during pyrolysis in an entrained flow bed reactor was elucidated, which provides theoretical guidance for selecting suitable processing technology for Zhundong coal. A typical coal was sampled, and a series of pyrolysis experiments with gradual and small increments in temperature was performed using an entrained flow bed reactor. Chars from pyrolysis at different temperatures were characterised using an improved sequential extraction method, inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray diffraction (XRD), and field emission scanning electron microscopy coupled with energy dispersive spectroscopy (FESEM-EDS) to determine the occurrence modes, chemical composition, and the distribution of AAEMs on the surface of coal char as a function of the change in pyrolysis temperature. In addition, thermodynamic “FactSage” software was used to simulate the evolution of AAEM species during the entire pyrolysis process. Thus, a transformation mechanism of AAEMs in Zhundong coal during pyrolysis is proposed. The results show that as the pyrolysis temperature increases, the contents of water-soluble and exchangeable sodium in coal char decrease, and their release results in a decrease in total sodium content. The insoluble potassium decomposes slightly at high temperatures, and the change in the total potassium content is not obvious. HCl-soluble magnesium and calcium species also decompose at high temperatures and then react with SiO2 and/or Al2O3 to form insoluble silicates or aluminosilicates. As a result, the surface of the coal char becomes enriched in insoluble magnesium and calcium. The variation trend of AAEMs obtained by the FactSage simulation is generally consistent with the experimental results. Upon the process of pyrolysis, the surface of the char sample becomes rough and is covered by cracks and holes. Consequently, some of the water-soluble AAEM species become gaseous and are released from the coal char upon an increase in the pyrolysis temperature. Then, some minerals reach the surface of the char through cracks and holes at high temperatures. The char matrix exhibits an inhibition effect on the release of these species, resulting in the enrichment of the char surface with AAEMs. Therefore, Zhundong coal is suitable for preparing high value-added carbon materials by pyrolysis.

The selective precipitation of metals using H2S produced biologically by sulfate-reducing bacteria (SRB) was put forward to dispose bioleaching solutions. Fe(III) is a common ion in the bioleaching solutions, and Fe(III) could inhibit the growth of SRB. The purpose of this paper is to investigate the influence of Fe( III) on the growth/activity of a mixed culture of SRB. Batch tests were carried out in flasks with Fe(III) concentrations at 02, 1, 5 and 10 g/L respectively. To avoid the impact of precipitation, addition of sodium citrate to the medium was also studied. Sulfate removal rates were greater than those in samples without iron, except in the system with a high iron concentration of 10 g/L. It is found that the mixed culture of SRB can tolerate high concentrations of Fe(III) up to 10 g/L After adding sodium citrate, SRB can tolerate higher concentrations of Fe(III), and the sulfate removal rate was the highest in the system with 5 g/L Fe(III). Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.

In this study, a high-sulfur and high-ash yield coal sample obtained from the Yanshan coalfield in Yunnan, China was analyzed. A series of char samples was obtained by pyrolysis at various temperatures (300, 400, 500, 600, 700, 800, and 900 °C) and at a fast heating rate (1000 °C/min). A comprehensive investigation using inductively coupled plasma mass spectrometry (ICP-MS), a mercury analyzer, ion-selective electrode (ISE) measurements, X-ray diffraction (XRD) analysis, and Fourier transform infrared (FTIR) spectroscopy was performed to reveal the effects of the pyrolysis temperature on the transformation behavior of trace elements (TEs) and the change in the mineralogical characteristics and functional groups in the samples. The results show that the TE concentrations in the raw coal are higher than the average contents of Chinese coal. The concentrations of Be, Li, and U in the char samples are higher than those in raw coal, while the opposite was observed for As, Ga, Hg, and Rb. The F and Se concentrations are initially higher but decrease with pyrolysis temperature, which is likely caused by associated fracturing with fluoride and selenide minerals. Uranium shows the highest enrichment degree, and Hg shows the highest volatilization degree compared to the other studied TEs. As the temperature increases, the number of OH groups decreases, and the mineral composition changes; for example, pyrite decomposes, while oldhamite and hematite occur in the chars. It is suggested that the behavior and fate of TEs in coal during fast pyrolysis are synergistically influenced by self-characteristic modes of occurrence and mineralogical characteristics.

Inhibition of VEGFR-2 kinase has been highlighted as one of the well-defined strategies to suppress tumor growth via blockade of angiogenesis. Guided by the principles of bioisosteric replacement and pharmacophoric fragment migration, a series of novel quinoxalinone derivates were designed, synthesized and evaluated for their VEGFR-2 inhibitory potencies. Among them, compounds 7c, 8b, 8c, 8e and 10b displayed antiangiogenic abilities via the in vitro tube formation assay (cellular level) and ex vivo rat aortic ring assay (tissue level) at a low concentration (0.1 μM). By means of in vivo zebrafish embryo model, two (Z)-3-(2-(pyridin-4-yl)vinyl)quinoxalinone derivates 8c and 8e showed significant antiangiogenesis effects, suggesting they have potentials to be developed into antiangiogenesis agents via further structural optimization. Moreover, these two compounds also demonstrated potent inhibition toward VEGFR-2 and B-raf kinases in a low concentration (1 μM). A possible interpretation of our evaluation result has been presented by a molecular docking study by docking representative compound 8c with VEGFR-2.

Because of the difficulty in disposing bioleaching solutions of nickel ore, an alternative remediation treatment, the selective precipitation of metals using H2S produced biologically by sulfate-reducing bacteria (SRB), has attracted extensive attention. SRB oxidize some carbon compounds anaerobically by reducing sulfate, in which electron donors are essential for the growth of SRB and the efficiency of biological sulfate reduction process. In this paper, influence of some electron donors on the growth and activity of SRB was studied. The carbon compounds tested included organic acids, alcohols, volatile fatty acid salts and carbohydrates. Results showed that sulfate-reducing activity decreases in the order of organic acids, volatile fatty acid salts, alcohols and carbohydrates. Considering the rate of sulfate removal and operating cost, the use of formic acid as an energy source in our experiments was found to be the most effective, resulting in 97% sulfate removal. (C) 2012 Elsevier B.V. All rights reserved.

The catalytic effect of Ag+ and Cu2+ on the dissolution of realgar was studied. In the absence of these catalysis ions, little realgar can be leached by Fe3+ either with or without bacteria. Silver ion can enhance the chemical leaching and bioleaching rate remarkably, while the catalytic effect of copper(II) ion was not so obvious. The catalytic mechanism of Ag+ and Cu2+ was similar: the surface arsenic was replaced by the formation of Ag2S or CuS, which was then dissolved by Fe3+. With Ag+ added, the influences of concentration of Fe3+ and temperature on chemical leaching were also investigated. (C) 2010 Elsevier B.V. All rights reserved.

The aim of this work was to explore the possibility of using sulfate-reducing bacteria for the retrieval of valuable metals from a bioleaching solution. Tests were conducted to determine whether the bacteria produced hydrogen sulfide that could be used to precipitate valuable metals from a bioleaching solution as sulfides. The approach consisted of continuous culture of sulfate-reducing bacteria to produce hydrogen sulfide in the first reactor and the subsequent metal precipitation in the second reactor. Batch and continuous experiments were carried out to determine the optimum process parameters. The advantage of this process was demonstrated including faster precipitation of valuable metals and the possibility of the metal precipitation in the form of sulfides. A new flow sheet for the separation of Ni and Cu by biogenic sulfide precipitation in the presence of magnesium was proposed.

Bioleaching liquors usually contain low concentration valuable metals and a major impurity (magnesium or calcium), and therefore it is a heavy burden and involves a complicated process to separate and enrich valuable metals from these liquors. An alternative process of selective precipitation of metals using H2S produced by sulfate reducing bacteria (SRB) is put forward. In this paper, sealed flasks were used to study the influence of Mg2+ in the form of MgCl2 center dot 6H(2)O and MgSO4 center dot 7H(2)O on the growth and activity of SRB, and the sulfide precipitation of bioleaching liquors was also studied. The experimental results show that Mg2+ ion concentration from MgCl2 center dot 6H(2)O or MgSO4 center dot 7H(2)O is a significant and favorable factor for SRB growth and activity. It is also demonstrated that enhanced activation of SRB by adding NaCl in liquor and the SRB have a high tolerance to salinity from NaCl. Adding MgSO4 center dot 7H(2)O provides a predominant condition for SRB growth, due to providing higher concentration of sulfate. The sulfide precipitation and separation of magnesium with H2S produced by SRB is found to be mainly dependent on the pH value and the H2S concentration. SRB culture solution can effectively precipitate Cu2+, Ni2+ and Fe3+ from synthetic leaching liquor in 2 min, while Mg2+ ions remain in the liquid phase. (C) 2008 Elsevier B.V. All right reserved.

Orpiment is one of the major arsenic sulfide minerals which commonly occurs in the gold mine environment and the weathering of this mineral can lead to the contamination of arsenic. In this study, chemical leaching experiments using 10g/L Fe(3+) at 35°C and 50°C were carried out and the results show that orpiment can be leached by Fe(3+) and the leaching rate of orpiment was significantly enhanced in the presence of Ag(+). The bioleaching experiments with mesophilic bacteria Acidithiobacillus ferrooxidans and moderate thermophilic bacteria Sulfobacillus sibiricus were carried out, showing that these two strains can survive in the mineral pulp and oxidize Fe(2+) to regenerate Fe(3+). Based on above results, it is believed that the leaching action of the acidic mining drainage by some bacteria can lead to the release of arsenic from orpiment. Different performances of At. ferrooxidans and S. sibiricus in the tests suggest they follow two different mechanisms and this point of view is further confirmed based on analyses of the composition and morphology of the mineral residue by SEM and EDS.

In view of the difficulty in treating the bioleaching solutions, the selective precipitation of metals using H2S produced biologically by sulfate reducing bacteria (SRB) was put forward. In this paper, two anaerobic fixed bed bioreactors fabricated from Plexiglas was used to produce hydrogen sulfide by continuous operation, porcelain rings and synthetic sponge (polyurethane foam) were used as immobilization carrier for supporting the biofilm growth. The results showed that high removal rate of SO 4 2− were achieved with both porcelain rings and synthetic sponge as immobilization carrier for continuous treatment. And in view of the stability of process and the removal rate of SO 4 2−, synthetic sponge was better as the immobilized carrier in the experiments, the removal rate of SO 4 2− with it reached 92%, and the process was easily operated.

A monitoring program for PM2.5 had been performed at two urban monitoring stations in Hong Kong from November 2000 to February 2001 and June 2001 to August 2001. PM2.5 samples were collected once every 6 days at PolyU and KT stations with the sampling duration of 24-h. A sum of 25 chemical species in PM2.5 were determined and selected for receptor models. Enrichment factors relative to earth crust abundances were evaluated and it was noted that most crustal elements including Al, Ti, Mg, Ca and K have small enrichment factors. Correlation and multivariate analysis technique, such as principal components analysis (PCA)/absolute principal components analysis (APCA) and cluster analysis (CA) are used for source apportionment to identify the possible sources of PM2.5 and to determine their contribution. Six factors at each site were isolated by using PCA/APCA and cluster analysis. Similar sources (crustal matter, automobile emission, diesel emission, secondary aerosols, tire wear, and non-ferrous smelter) are identified by the PCA/APCA and cluster analysis.