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In consideration of recycling solid waste to achieve high value-added products, glass-ceramics have been fabricated from municipal solid waste incineration (MSWI) fly ash, pickling sludge (PS), and waste glass (WG) by melting at 1450 °C firstly to achieve parent glass and then crystallizing at 850 °C. Results demonstrated that heavy metals have been well solidified in the prepared glass-ceramics, and relatively/extremely low leaching concentrations of heavy metals have been detected. The synthetic toxicity index of heavy metals has been greatly reduced from 7-18 to <3.2 after crystallization treatment, and the leaching concentrations of Cr, Ni, Zn, Cu, and Pb are 0.15, 0.05, 0.26, 0.12, 0.19 mg L-1 respectively. Chemical morphology analysis, principal component analysis, TEM and EPMA were utilized to clarify the migration, transformation, and solidification mechanism of heavy metals from the as-received solid wastes. The major heavy metals, Cr and Ni which is responsible for the most toxicity, mainly exist in form of the oxidation state and residual state in parent glass, while the residual state in the glass-ceramics. The solidification performance was mostly positively correlated with the form of residue state, which the stability of heavy metals in glass-ceramics is improved. The solidification mechanism of heavy metals in glass-ceramics could be explained by the combination of chemical solidification/stabilization and physical coating. The TEM and EPMA confirmed that Cr and Ni mainly exist in the spinel crystalline (NiCr 2 O 4 , Fe 0.99 Ni 0.01 Fe 1.97 Cr 0.03 O 4) by solid solution or chemical substitution, and a small amount of Cr in the diopside phase. Pb, Cu, and Zn are homogenously dispersed in the glass-ceramics, which is considered as physical coating solidification. [Display omitted] [ABSTRACT FROM AUTHOR]

The production and use of intentionally-produced polychlorinated biphenyls (PCBs) in China have a short history compared with countries of North America and Europe, where technical PCB mixtures were manufactured in large amounts for decades before being banned. Unintentionally-produced PCB emissions increased dramatically in China, leading to unique profiles of PCB burdens. This study first time evaluated 208 individual PCB congeners at 94 sites from surface sediments of the East China Marginal Seas (ECMSs) and explored their sources. Non-technical PCBs transported from atmospheric transport and river discharge played a dominant role in most areas of the ECMSs, while historical residuals of technical PCBs occupied the fine-grained sediments in muddy areas of the central Yellow Sea (YS), regarding to the low sedimentation rate in the central YS. Furthermore, emissions from Taizhou located on the coast of the East China Sea (ECS), which is an important electronic waste dismantling site in East China, contributed additional technical PCBs to the inner shelf of the ECS. Our results indicate that non-technical PCBs have become the dominant PCB species in the ECMSs, and emphasize the synergistic effects of large riverine input, long-range atmospheric transport, and muddy shelf deposition on PCB source and sink of in marginal seas. [Display omitted] • Non-technical PCBs dominate the total PCB burden in the ECMSs sediments. • Non-technical PCBs comprise 76% of PCBs from riverine and atmospheric inputs. • Technical PCBs are concentrated in central sea areas and e-waste recycling sites. • Atmospheric deposition controls the PCB concentrations in the YS and BS. • River discharge and e-waste emissions regulate the PCB concentrations in the ECS. [ABSTRACT FROM AUTHOR]

• 22 new compounds with biphenyl imidazole scaffolds were designed and synthesized. • Compound 12m showed better antifungal activity than fluconazole. • The structure-activity relationships of compounds were discussed. • Compound 12m exhibited low inhibition profiles for human cytochrome P450 isoforms. To further explore the structure activity relationships (SARs) of our previously discovered antifungal lead compound (1), a series of biphenyl imidazole analogues were designed, synthesized and evaluated for their in vitro antifungal activity. Many of the synthesized compounds showed excellent activity against Candida albicans and Candida tropicalis. Among these compounds, 2-F substituted analogue 12m displayed the most remarkable in vitro activity against C. albicans , C. neoformans , A. fumigatus and fluconazole-resistant C. alb. strains, which is superior or comparable to the activity of the reference drugs fluconazole and itraconazole. Notably, the compound 12m exhibited low inhibition profiles for various human cytochrome P450 isoforms and showed low toxicity to mammalian A549 cells and U87 cells. The SARs and binding mode established in this study will be useful for further lead optimization. [ABSTRACT FROM AUTHOR]

To further enhance the anti- Aspergillus efficacy of our previously discovered antifungal lead compound 1 , a series of benzoheterocycle analogues were designed, synthesized and evaluated for their in vitro antifungal activity. The most promising compounds 13s and 14a exhibited excellent antifungal activity against C. albicans , C. neoformans , A. fumigatus and fluconazole-resistant C. albicans strains, that was superior or comparable to those of the reference drugs fluconazole and voriconazole. GC–MS analyses suggested that the novel compound 13s might have a similar mechanism to fluconazole by inhibiting fungal lanosterol 14α-demethylase (CYP51). Furthermore, compounds 13s and 14a exhibited low inhibition profiles for various human cytochrome P450 isoforms as well as excellent blood plasma stability. [ABSTRACT FROM AUTHOR]

To further enhance the anti- Aspergillus efficacy of our previously discovered antifungal lead compounds ( 1 ), a series of aromatic heterocyclic derivatives were designed, synthesized and evaluated for in vitro antifungal activity. Many of the target compounds showed good inhibitory activity against Candida albicans and Cryptococcus neoformans . In particular, the isoxazole nuclei were more suited for improving the activity against Aspergillus spp . Among these compounds, 2-F substituted analogues 23g and 23h displayed the most remarkable in vitro activity against Candida spp. , C. neoformans , A. fumigatus and fluconazole-resistant C.alb. strains, which is superior or comparable to the activity of the reference drugs fluconazole and voriconazole. Notably, the compounds 23g and 23h exhibited low inhibition profiles for various isoforms of human cytochrome P450 and excellent blood plasma stability. [ABSTRACT FROM AUTHOR]

Fungal infections have became a serious medical problem due to their high incidence and mortality. We describe the discovery and structure-activity relationships studies (SARs) of a series of novel biphenyl imidazole derivatives with excellent antifungal activities against Candida albicans and Cryptococcus neoformans . The most promising compounds 12f – g and 19a – b exhibited excellent activity with minimum inhibitory concentration (MIC) values in the range of 0.03125–2 μg/mL. Preliminary mechanism studies showed that the potent antifungal activity of compound 12g stemed from inhibition of CYP51 in Candida albicans . Furthermore, compounds 12g and 19b exhibited low inhibition profiles for various human cytochrome P450 isoforms. The SARs and binding mode established in this study will be useful for further lead optimization. [ABSTRACT FROM AUTHOR]

A series of compounds with benzothiazole and amide-imidazole scaffolds were designed and synthesized to combat the increasing incidence of drug-resistant fungal infections. The antifungal activity of these compounds was evaluated in vitro , and their structure-activity relationships (SARs) were evaluated. The synthesized compounds showed excellent inhibitory activity against Candida albicans and Cryptococcus neoformans . The most potent compounds 14o , 14p , and 14r exhibited potent activity, with minimum inhibitory concentration (MIC) values in the range of 0.125–2 μg/mL. Preliminary mechanism studies revealed that the compound 14p might act by inhibiting the CYP51 of Candida albicans . The SARs and binding mode established in this study are useful for further lead optimization. [ABSTRACT FROM AUTHOR]

Abstract: Electrospinning as a versatile method for preparation of nanofibers has been used to fabricate the polyvinylalcohol nanofibers containing equal molar of aluminum nitrate and copper acetate. After pretreated at 400°C, the composite fibrous mats were annealed at 1100°C in air for 5h and then the delafossite-structured p-type CuAlO2 ceramics fibrous mats were obtained. The obtained CuAlO2 ceramics fibrous mats were characterized by scanning electrical microscope, X-ray diffraction and diffuse reflectance spectroscopy. The direct energy gap of the prepared CuAlO2 ceramics fibrous mats was measured to be about 3.38eV. The CuAlO2 behaved like semiconductors and the thermally activated energy was about 0.25eV. [Copyright &y& Elsevier]

Abstract: Polyacrylonitrile nanofibers containing different amounts of gold nanoparticles have been prepared by electrospinning technique. By using the gold nanoparticles as seeds, thin continuous gold films have been deposited on the surface of polyacrylonitrile fibers through self-catalyzed reduction of chloroauric acid in solution. The conductivities of the fibrous mats increase with the amount of gold deposited on the fibers increase. The smooth continuous thin gold films tend to form on the fibers surface when the organic fibers contain more gold seeds, while coarse films tended to form on the fibers containing less gold seeds. The electrocatalytic activity of the fibrous mats electrodes towards the methanol oxidation in alkaline medium has been investigated, indicating that these electrodes exhibit higher electrocatalytic activity than pure gold electrode because of their three-dimensional structures. The results also indicate that the mats with smooth gold coating exhibit higher electrocatalytic activity than that with coarse gold coating. [Copyright &y& Elsevier]

• The novel TGR5 agonists were designed and synthesized. • Compounds 19d and 19e showed excellent agonistic activities against hTGR5. • Compounds 19d and 19e exhibited high selectivity against FXR. • Compounds 19d and 19e suppressed the excursion of glucose levels. • Compound 19d could stimulate GLP-1 secretion by activation of TGR5. TGR5 is emerging as an important and promising target for the treatment of diabetes, obesity and other metabolic syndromes. A series of novel 1-benzyl-1 H -imidazole-5-carboxamide derivatives was designed, synthesized and evaluated in vitro and in vivo. The most potent compounds 19d and 19e exhibited excellent agonistic activities against hTGR5, which was superior to those of the reference drugs INT-777 and LCA. In addition, compounds 19d and 19e exhibited good selectivity against FXR and presented significant glucose-lowering effects in vivo. Compound 19d could stimulate GLP-1 secretion by activating of TGR5. [ABSTRACT FROM AUTHOR]

Municipal solid waste incinerated (MSWI) fly ash and pickling sludge contain heavy metals such as Cr, Pb, Ni, etc., which are harmful to the environment but also suitable to be the nucleating agents in glass-ceramics preparation. In this paper, MSWI fly ash, pickling sludge, and waste glass were melted at 1400 °C for 3 h, and the obtained parent glass was nucleated and crystallized at 800 °C for 0.5 h. Glass-ceramics was successfully prepared by the one-step process. The effects of the content of pickling sludge on crystalline properties of parent glass and the physicochemical properties of glass-ceramics have been systematically discussed. The gap between nucleation temperature (T n) and crystallization temperature (T c) can be narrowed with higher content of pickling sludge, which caused fracture of the glass network (Si-O) and generation of the nonbridging oxygen (NBO), promoting the formation of diopside phase. As a result, nucleation and crystallization can be finished at the same temperature, called one-step process. The sample PS22 with 22 wt% pickling sludge added performed the best crystallization ability for having the narrowest gap (ΔT = 177 °C) between T c and glass transition temperature (T g) and the highest ratio of NBO to total oxygen (T) (NBO/T = 1.72). The Vickers' hardness and bending resistance of the products are 13.11 GPa and 135.84 MPa, respectively. The glass-ceramics are composed of homogeneously distributed diopside, donathite-spinel and glass phase. The toxic heavy metals are effectively stabilized by glass-ceramics. This study provides insights into more efficient and cleaner utilization of MSWI fly ash, pickling sludge and waste glass as glass-ceramic materials. Image 1 • Glass-ceramics were made from MSWI fly ash and pickling sludge and waste glass. • Properties of glass-ceramics by one-step were satisfied with the industrial standard. • Pickling sludge is an efficient nucleating agent in terms of glass crystallization. • Pickling sludge depolymerizes the glass network and decreases the thermal stability. [ABSTRACT FROM AUTHOR]

Multiple types of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and hexachlorobenzene (HCB), can be unintentionally released from combustion or thermal industrial processes, which are speculated to be the main sources of these contaminants, as they were banned on production and use since several decades ago. In this study, concentrations and sources of 40 PCBs, 39 PCNs, and HCB were analyzed in air samples collected during the period 2012–2015 at a background site in east China. ΣPCBs, ΣPCNs, and HCB were in the range of 9–341 pg/m3, 6–143 pg/m3, and 14–522 pg/m3, respectively. Seasonal characteristics with high levels in winter and low levels in summer were observed for PCNs and HCB. PCBs also exhibited slightly higher levels in winter. Source apportionment was conducted, using polycyclic aromatic hydrocarbons (PAHs) as combustion sources indicator, combined with principal component analysis (PCA) and positive matrix factorization (PMF) model. The results indicated that the legacy of past produced and used commercial PCBs was the dominant contributor (∼56%) to the selected PCBs in the atmosphere in east China. PCNs were mainly emitted from combustion sources (∼64%), whereas HCB almost entirely originated from combustion process (>90%). Image 1 • PCNs and HCB in air in east China showed seasonality with high levels in winter. • Common PCBs were dominated (∼56%) by the legacy commercial products. • Combustion sources were the dominant contributor to PCNs (∼64%) and HCB (>90%). [ABSTRACT FROM AUTHOR]

Secondary aluminum dross (SAD) is a solid waste of aluminum dross after it is extracted aluminum. Soda-lime-aluminosilicate (SLAS) glass-ceramics with high alumina contents (over 30 wt%) were successfully manufactured from SAD using pyrometallurgy without additional nucleation agents. The nucleation process of SLAS glass was studied, and 670 °C was selected as the nucleation temperature according to differential scanning calorimetry and X-ray diffraction results. Field-emission transmission electron microscopy was applied to study the microstructure of the specimens thermally treated at 670 °C for 3 and 12 h. Nucleation consisted of two parts: iron oxide nucleation and jadeite nucleation. During iron oxide nucleation, when the thermal treatment time increased from 3 to 12 h, the iron oxides first congregated in an amorphous phase and a small amount of metastable crystal; then, the congregated iron oxides crystallized into hematite and magnetite, which acted as crystal nuclei. During jadeite nucleation, the jadeite spontaneously crystallized from the glass matrix after thermal treatment at 670 °C. When the thermal treatment time increased from 3 to 12 h, the size of the jadeite crystals increased from approximately 6 to 12 nm. Jadeite crystals with a diameter of 12 nm acted as crystal nuclei. For glass-ceramics with a high content of aluminum and sodium, jadeite crystals can act as crystal nuclei without additional nucleation agents. [Display omitted] [ABSTRACT FROM AUTHOR]

Surface modification of carbon nanotubes (CNTs) were performed by grafting of hydroxyl-terminated polydimethylsiloxane (HPDMS) covalently. The results of dissolution experiments revealed that long-time stable dispersions of HPDMS-functionalized CNTs (CNTs-HPDMS) were achieved in a range of solvents including ethanol, ethyl acetate, dimethylbenzene and cyclohexane, even after being placed for 3 months. Subsequently, CNTs-HPDMS were incorporated into poly(methylphenylsiloxane) (PMPS) matrix to prepare composites. Scanning electron microscopy analysis showed that CNTs-HPDMS had homogeneous dispersion and strong interfacial adhesion in PMPS, which led to much better mechanical properties of composites compared to those filled with untreated CNTs. Furthermore, the incorporation of CNTs-HPDMS significantly enhanced the thermal stability of PMPS composites both under nitrogen and air. The improved barrier effect of CNTs-HPDMS resulted from the better filler dispersion was considered to play a crucial role, which on the one hand suppressed the depolymerization of PMPS under nitrogen and on the other hand inhibited the oxygen diffusion in matrix under air. Besides, the hydroxyl groups of HPDMS could react with PMPS to form additional crosslinking during heating, and thus delayed the degradation of PMPS to some extent. [ABSTRACT FROM AUTHOR]

A wide range of studies have characterized different types of biosorbent, with regard to their interactions with chemicals. This has resulted in the development of poly-parameter linear free energy relationships (pp-LFERs) for the estimation of partitioning of neutral organic compounds to biological phases (e.g., storage lipids, phospholipids and serum albumins). The aims of this study were to explore and evaluate the influence of implementing pp-LFERs both into a one-compartment fish model and a multi-compartment physiologically based toxicokinetic (PBTK) fish model and the associated implications for chemical risk assessment. For this purpose, fish was used as reference biota, due to their important role in aquatic food chains and dietary exposure to humans. The bioconcentration factor (BCF) was utilized as the evaluation metric. Overall, our results indicated that models incorporating pp-LFERs (R 2 = 0.75) slightly outperformed the single parameter (sp) LFERs approach in the one-compartmental fish model (R 2 = 0.72). A pronounced enhancement was achieved for compounds with log K OW between 4 and 5 with increased R 2 from 0.52 to 0.71. The minimal improvement was caused by the overestimation of lipid contribution and underestimation of protein contribution by the sp-approach, which cancelled each other out. Meanwhile, a greater improvement was observed for multi-compartmental PBTK models with consideration of metabolism, making all predictions fall within a factor of 10 compared with measured data. For screening purposes, the K OW -based (sp-LFERs) approach should be sufficient to quantify the main partitioning characteristics. Further developments are required for the consideration of ionization and more accurate quantification of biotransformation in biota. [ABSTRACT FROM AUTHOR]

Bangladesh is one of the most populated countries in the world. Rapid industrialization and urbanization in the last decades have caused emission of pollutants in the environment. The aim of the study was to assess atmospheric 16 polycyclic aromatic hydrocarbons (Σ 16 PAH) in Bangladesh using PUF-PASs deployed in 5 metropolitan cities and one large non-metropolitan city from December 2017 to September 2018. Spatial distribution of Σ 16 PAH ranged from 3.6 ± 1.1 to 22.4 ± 6.9 ng/m3. The maximum concentration of 22.4 ± 6.69 ng/m3 was found on the site-23 (urban), a newly established metropolitan city. Reasonably, the lowest concentration (3.6 ± 1.1 ng/m3) was recorded at the rural site (site-7). Seasonal variation of ∑ 16 PAH was found to be 4.8–28.4, 2.2–12.0 and 2.7–30.5 ng/m3 in the winter, pre-monsoon and monsoon, respectively. Among the PAH isomers, phenanthrene, fluoranthene and pyrene significantly contributed to the total concentrations of PAHs with 30.4, 27.8 and 20.1% in the winter, 18.9, 29.4 and 21.9% in pre-monsoon and 14.2, 29.9 and 21.9% in monsoon, respectively. Seasonal variation of PAHs followed the decreasing order: winter > monsoon > pre-monsoon. Molecular weight-based results revealed that 4- and 3-rings PAHs (4-rings: 53–60%; 3-rings: 23–37%) mostly contributed to the total concentration of PAHs. Diagnostic ratios, PMF model and PCA results suggested that combustion of coal, petroleum, and incineration of biomass/plastics and municipal solid waste are the primary sources of PAHs in Bangladesh. Calculated BaP TEQ and BaP MEQ and ICR values were higher for the children than that of the adults. The higher values of the BaP TEQ and BaP MEQ and ICR compared to those suggested by the WHO and USEPA, imply that population of Bangladesh, particularly children, may be at high risk for health problems from PAHs. [Display omitted] • Monitoring of atmospheric PAHs using PUF-PASs in 6 metropolitan cities in Bangladesh. • High-way, urban, biomass-based combustion, dumping sites were highly contaminated. • Seasonal variation of PAHs follows decreasing order: winter > monsoon > pre-monsoon. • Combustion of coal, petroleum, biomass and municipal waste possible sources of PAHs. • Risk assessment shows high potential health risk caused by PAHs. [ABSTRACT FROM AUTHOR]

Black carbon (BC) is ubiquitous in the environment and is a significant component of the refractory carbon pool. However, its sources, biogeochemical processes, and environmental residence times are poorly understood. One important reason is that the technical protocols for isolating/analyzing BC vary across different matrices, thereby bringing inconsistency among studies on BC in different environment media. Benzene polycarboxylic acids (BPCA), produced by nitric acid oxidation of the condensed aromatic structure that is common in BC and BC-like substances, has been proven to be a useful molecular proxy for tracking BC in the Earth's surface. Here, we introduce a new technical approach for the compound-specific dual-carbon isotope (δ13C and Δ14C) analysis of BPCA. The BPCA compounds are isolated using preparative liquid chromatography, in which trifluoroacetic acid is used in the mobile phase instead of phosphoric acid. This allows complete removal of solvent from the isolated BPCA fraction, so that conversion of BPCA isolates into CO 2 can be done by conventional oxidation methods for off-line Δ14C analysis with accelerator mass spectrometry. Liquid chromatography (void column)-stable carbon isotope ratio mass spectrometry is employed to measure δ13C of the isolated BPCA, leaving as much BPCA carbon amount as possible for 14C analysis. Blockage of oxidation chamber due to incomplete oxidation of other organic acids in the samples is avoided thanks to preliminary isolation of BPCA. We tested the approach by applying it to solid and dissolved BC species in a suite of environmental reference materials, including maize char, coal, riverine natural organic matter (NOM 2R101N), marine sediment (SRM 1941b), urban dust (SRM 1649b), and coke-polluted soils. We assessed the offsets of BPCA-δ13C and BPCA-Δ14C values caused by procedural carbon contaminations to correct measured carbon isotopic values. Paired δ13C-Δ14C data of individual BPCA were plotted to validate and demonstrate the ability of this dual carbon isotope technique in tracking BC across different environmental matrices. We observed slightly different δ13C-Δ14C signatures among individual BPCA, indicating that the less condensed BC may have younger apparent radiocarbon ages. [Display omitted] • We outline a new approach for compound-specific δ13C-Δ14C analysis of BPCA. • Mobile phases of BPCA fractions isolated with HPLC are totally removed. • Validation using BC reference materials of various environmental media. [ABSTRACT FROM AUTHOR]

Total suspended particles (TSP) and gaseous samples were collected by using a high-volume sampler from March 2012 to March 2013 and January 2018 to January 2019 at a background site (Jinsha, JSH) in central China to study the chemical characteristics, seasonal variations, and potential sources of polycyclic aromatic hydrocarbons (PAHs). The average concentrations of ∑ 15 PAHs were 24.55 ± 9.19 ng m−3 in 2012/2013 and 20.98 ± 9.77 ng m−3 in 2018/2019. Low-ring PAHs were more concentrated in gas phase while high-ring PAHs were prone into particle phase. The concentrations of PAHs in the two sampling years were high in winter but low in summer and autumn. The relationships between the gas concentrations of PAHs and temperature indicated that most PAHs were influenced by long-range atmospheric transport (LRAT) in 2012/2013 and in 2018/2019, excluding anthracene (Ant) and pyrene (Pyr) were partially affected by air-surface re-volatilization in 2012/2013. The source of atmospheric PAHs at JSH was similar in 2012/2013 and 2018/2019,which was mainly due to the LRAT of PAHs emitted from biomass/fossil fuel combustion in the northern area of JSH. From 2012/2013 to 2018/2019, there was no significant difference between the concentrations of PAHs in spring and winter, whereas the concentrations of PAHs decreased from 2012/2013 to 2018/2019 in summer. In all, the control of PAHs at the source region was partially effective from 2012/2013 to 2018/2019. [Display omitted] • Atmospheric concentrations of PAHs at JSH in the two sampling years were both high in winter. • Mixture sources mainly contributed in 2012/2013, while combustion sources were dominant in 2018/2019. • Atmospheric PAHs at JSH were largely influenced by LRAT from the northern area of JSH in both 2012/2013 and 2018/2019. • The control of PAHs at source region was partly effective from 2012/2013 to 2018/2019. [ABSTRACT FROM AUTHOR]

• Glass ceramic foams with high strength is developed by multiple solid wastes. • Secondary aluminum ash as self-foaming material is proposed to prepare glass ceramic foams. • The self-foaming mechanism relies on the oxidation reaction of AlN. • The degree of polymerization in glass with different alkalinity is analyzed. Glass ceramic foam with high strength was developed using municipal waste incineration bottom ash, fly ash, pickling sludge and secondary aluminum ash as raw materials without foaming agent. The effect of the secondary aluminum ash content and alkalinity on the pore morphology, porosity, water absorption, compression strength and bulk density of glass ceramic foams has been evaluated. The results showed that the increase of secondary aluminum ash content is beneficial to gas generation, but it will reduce the formation of liquid phase, resulting in the variation of pore morphology. In the process of alkalinity adjustment, the degree of polymerization of glass decreased first and then increased, which is similar to the change of max pore size, providing guidance for quantitative analysis of pore formation. The optimized sample reached porosities up to 63.02%, bulk density of ~1.42 g/cm3, and excellent compressive strength ~41.93 MPa. The analysis of self-foaming mechanism proved that secondary aluminum ash can be used as a self-foaming waste results from the oxidation reaction of AlN. In this work, a clean and sustainable utilization method has been proposed for recycling multiple solid wastes by preparing glass ceramic foams with a potential application for construction insulation materials with load-bearing. Moreover, an innovative exploration of secondary aluminum ash as the self-foaming waste in high temperature environmental was proposed. [ABSTRACT FROM AUTHOR]

To discover broad spectrum antifungal agents, two strategies were applied, and a novel class of l -amino alcohol derivatives were designed and synthesized. 3-F substituted compounds 14i , 14n , 14s and 14v exhibited excellent antifungal activities with broad antifungal spectra against C. albicans and C. tropicalis , with MIC values in the range of 0.03–0.06 μg/mL, and against A. fumigatus and C. neoformans , with MIC values in the range of 1–2 μg/mL. Notably, Compounds 14i , 14n, 14s and 14v also displayed moderate activities against fluconazole-resistance strains 17# and CaR that were isolated from AIDS patients. Moreover, only compounds in the S -configuration showed antifungal activity. Preliminary mechanistic studies showed that the potent antifungal activity of compound 14v stemmed from inhibition of C. albicans CYP51. Compounds 14n and 14v were almost nontoxic to mammalian A549 cells, and their stability in human plasma was excellent. Image 1 • Compounds 14i , 14n, 14s and 14v exhibited excellent antifungal activities with broad antifungal spectra. • Compounds 14i , 14n, 14s and 14v showed moderate antifungal activities against fluconazole-resisitent Candida albicans. • l Compound 14v reduced the content of ergosterol in a dose-dependent manner. • l Compounds 14n and 14v were almost nontoxic to mammalian A549 cells. • Compound 14v showed excellent stability in human plasma. [ABSTRACT FROM AUTHOR]

Cytochromes P450 (CYPs) play an important role in the metabolism of endogenic and xenobiotic substances, especially drugs. In addition, many CYPs may serve as targets for disease treatment. However, due to the presence of a common heme, the hydrophobicity of the CYP binding cavity, and the high homology within the binding pocket, most CYP inhibitors lack selectivity, which often leads to drug-drug interactions. Therefore, it is meaningful to develop highly selective CYP inhibitors. In this review, we summarize some of the strategies that have been used to develop highly selective CYP inhibitors, such as the weakening of the heme-binding group interaction, reduction of molecular lipophilicity and introduction of small structural changes within compounds. [ABSTRACT FROM AUTHOR]

Polyaromatic organic matter (POM) is an important group of pollutants and light absorbers in ambient aerosols, which consists of a wide range of chemicals with fused benzene rings. POM in ambient aerosols is mainly derived from the incomplete combustion of fossil fuel and biomass. Source apportionment of POM is crucial for advising efficient mitigation of anthropogenic emissions, but that is a challenge due to the complicated composition of POM and ambient aerosols. Benzene polycarboxylic acids (BPCAs) have recently been introduced as molecular markers of atmospheric POM. Compound-specific radiocarbon analysis of BPCAs is expected to be a powerful tool for apportioning fossil sources and contemporary (i.e., biomass burning) sources of POM in ambient aerosols, yet this application is still lacking. We developed a method for radiocarbon analysis of BPCAs substituted with 3–6 carboxylic groups (B6CA, B5CA, B4CAs and B3CAs). BPCAs were isolated with preparative liquid chromatography with high recoveries (≥85%). The method is validated with reference materials with fossil and contemporary radiocarbon signatures. Successful radiocarbon analysis of BPCAs was achieved for these reference materials after correcting for the presence of average blanks (B6CA: 1.2 ± 0.2 μg, B5CA: 2.3 ± 0.6 μg, individual B4CAs: 2.7 ± 0.2 μg and individual B3CAs: 6.9 ± 0.7 μg). Source apportionment of POM based on radiocarbon analysis of BPCAs was performed for an urban dust reference material, as well as bulk aerosols and water-soluble, methanol-soluble fractions of ambient aerosols from a megacity of southern China. The results show varied contributions of fossil and contemporary sources among different POM fractions. [Display omitted] • Benzene polycarboxylic acids (BPCAs) are used to track polyaromatic organic matter (POM). • A method of compound-specific radiocarbon analysis (CSRA) of BPCAs is developed. • Successful CSRA of BPCAs is achieved for reference and ambient materials. • Sources of POM in ambient aerosols are apportioned by CSRA of BPCAs. • Fossil-contemporary source patterns vary between different POM fractions. [ABSTRACT FROM AUTHOR]

The effect of exogenous phosphate (P, 200 mg⋅kg −1 soil) on the lability and phytoavailability of arsenic (As) was studied using the diffusive gradients in thin films (DGT) technique. Lettuce were grown on the As-amended soils following the stabilization of soil labile As after 90 days incubation. Phosphate (P) application generally facilitated plant growth except one grown on P-sufficient soil. Soil labile As concentration increased in all the soils after P application due to a competition effect. Plant As concentration increased in red soils collected from Hunan Province, while decreases were observed in the other soils. Even though, an overall trend of decrease was obtained in As phytoavailability along with the increase of DGT-measured soil labile P/As molar ratio. The functional equation between P/As and As phytoavailability provided a critical value of 1.7, which could be used as a guidance for rational P fertilization, thus avoiding overfertilization. [ABSTRACT FROM AUTHOR]

Black carbon (BC) is an important component of the brown clouds, contributing to climate and health effects of air pollution. In this work, we developed a new method for measuring BC concentrations and its radiocarbon isotope (14C) using quartz wool disk passive air samplers (Pas-QW). A field calibration study was conducted at two sampling sites (Guangzhou and Yantai), using an improved thermal/optical method to measure BC. Uptake profiles of Pas-QW were linear over the 77 days that the samplers were deployed, and the average sampling rate of BC measured was 1.1 ± 0.2 m3/day. The method was found to be reproducible with coefficients of variation as low as 17% for BC measured in ambient passive samples. Furthermore, passive sampling was carried out at six sites in the Indo-China Peninsula (ICP) from January to April and June to September of 2016. The high BC concentrations and the high fraction of modern carbon (f M) values emphasizes that ICP is still dominated by biomass burning emissions (residential cooking and agricultural burning), both in dry and wet seasons. This study provides a proof concept and methodology for the application of Pas-QW to cost-effectively expand measurements of BC at the global scale. [Display omitted] • A new method for measuring BC and its 14C using quartz wool disk passive samplers. • The method requires no sample processing and have good reproducibility for BC. • The relative contribution of biomass burning to BC can reach 67 ± 13% in ICP, with obvious spatiotemporal heterogeneity. [ABSTRACT FROM AUTHOR]

Cholesteryl ester transfer protein (CETP) is a potential target for cardiovascular disease therapy as inhibition of CETP leads to increased HDL-C in humans. Based on the structure of Merck's biphenyl CETP inhibitor, we designed novel N , N -substituted-cycloalkenyl-methylamine scaffold derivatives by utilizing core replacement and conformational restriction strategies. Consequently, twenty-eight compounds were synthesized and evaluated for their inhibitory activity against CETP. Their preliminary structure-activity relationships (SARs) studies indicate that polar substituents were tolerated in moiety A and hydrophobic alkyl groups at the 5-position of cyclohexene were critical for potency. Among them, compound 17a , bearing an N -(5-pyrazolyl-pyrimidin-2-yl)-cycloalkenyl- methylamine scaffold, exhibited excellent CETP inhibitory activity (IC 50 = 0.07 μM) in vitro . Furthermore, it showed an acceptable pharmacokinetic profile in S-D rats and efficient HDL-C increase in high-fat fed hamsters. [ABSTRACT FROM AUTHOR]

[Display omitted] Field-based sampling can provide more accurate evaluation than MODIS in regional biomass burning (BB) emissions given the limitations of MODIS on unresolved fires. Polyurethane foam-based passive air samplers (PUF-PASs) are a promising tool for collecting atmospheric monosaccharides. Here, we deployed PUF-PASs to monitor monosaccharides and other BB-related biomarkers and presented a dataset of 31 atmospheric BB-related biomarkers in the Indo-China Peninsula (ICP) and Southwest China. The peak concentrations of monosaccharides in the ICP occurred before monsoon season. The highest concentrations were in the eastern Mekong plain, while the lowest were along the eastern coast. BB-related biomarkers displayed elevated concentrations after April, particularly in the monsoon season; however, fewer active fires were recorded by MODIS. This revealed the importance of MODIS unresolved fires (e.g., indoor biofuel combustion, small-scale BB incidents, and charcoal fires) to the regional atmosphere. The PAS derived levoglucosan concentrations indicated that, with the inclusion of MODIS unresolved fires, the estimated top-down emissions of PM (4194–4974 Gg/yr), OC (1234–1719 Gg/yr) and EC (52–384 Gg/yr) would be higher than previous bottom-up estimations in the ICP. Future studies on these MODIS unresolved fires and regional monitoring data of BB are vital for improving the modeling of regional BB emissions. [ABSTRACT FROM AUTHOR]

A series of N , N -3-phenyl-3-benzylaminopropanamide derivatives were identified as novel CETP (cholesteryl ester transfer protein) inhibitors. In our previous study, lead compound L10 was discovered by pharmacophore-based virtual screening (Dong-Mei Zhao et al., 2014). Based on L10 (IC 50 8.06 μM), compound HL6 (IC 50 10.7 μM) was discovered following systematic structure variation and biological tests. Further optimization of the structure–activity relationship (SAR) resulted in N , N -3-phenyl-3-benzylaminopro panamides derivatives as novel CETP inhibitors. They were synthesized and evaluated against CETP by BODIPY-CE fluorescence assay. Among them, HL16 (IC 50 0.69 μM) was a highly potent CETP inhibitor in vitro. In addition, HL16 exhibited favorable HDL-C enhancement and LDL-C reduction in vivo by hamster. The molecular docking of HL16 into the CETP was performed. The binding mode demonstrated that HL16 occupied the CETP binding site and formed interactions with the key amino acid residues. [ABSTRACT FROM AUTHOR]

[Display omitted] • BS atmospheric Σ 10 OPEs level was 7.65 ± 6.42 ng m−3 with rising trend in 2014–2019. • volatilization of TCEP and TCPP from seawater dominated atmospheric concentrations. • volatilization of TCEP and TCPP deriving from coastal seawater accounting for 73% • river input was the main source of TCEP and TCPP for the BS seawater. Organophosphate esters (OPEs) are still produced and used in large quantities in the world-wide, and the environmental burden and behavior have generated widespread concern, especially in some large-scale waterbodies. This study conducted a comprehensive assessment on the temporal and spatial variabilities and budget of OPEs to trace the source for the Bohai Sea (BS), based on a 5-year seasonal monitoring campaign (June 2014 to May 2019) of 12 atmospheric sites around the BS and our previous studies. The average concentration of Σ 10 OPEs in atmosphere during the sampling period was 7.65 ± 6.42 ng m−3, and chlorinated OPEs were the major compounds. The Seasonal-Trend decomposition procedure based on Loess (STL) analyzed that during the 5-year sampling period, the atmospheric concentrations of Σ 10 OPEs had a slightly increasing trend with a rate of + 0.092 ng m−3 yr−1, and the seasonal concentrations had a distinct seasonal distribution. The highest concentration of Σ 10 OPEs was observed at the sampling site of Dalian, followed by Tianjin, Yantai, and Beihuangcheng. The estimation of the fugacity ratios and air–water gas exchange fluxes established that the concentration levels of two major components of chlorinated OPEs (tris-(2-chloroethyl) phosphate (TCEP) and tris-(1-chloro-2-propyl) phosphate (TCPP)) in the atmosphere were dominated by their volatilization from BS's seawater (1.24 ± 0.46 t yr−1 for TCEP and 5.15 ± 2.15 t yr−1 for TCPP), with 73% deriving from the coastal seawater. The budget assessment suggested that the volatile fluxes of TCEP and TCPP accounted for 8% and 29% of their storages (15.6 ± 5.32 t for TCEP and 17.6 ± 6.70 t for TCPP) in the BS seawater, which were mainly contributed by continental river input (20% for TCEP and 42% for TCPP). The efforts indicated that river inputs of TCEP and TCPP needed to be paid more attention for the improvement of environmental quality of the BS. [ABSTRACT FROM AUTHOR]

To discover antifungal compounds with broad-spectrum and stable metabolism, a series of 2-(benzo[ b ]thiophen-2-yl)-4-phenyl-4,5-dihydrooxazole derivatives was designed and synthesized. Compounds A30-A34 exhibited excellent broad-spectrum antifungal activity against Candida albicans with MIC values in the range of 0.03–0.5 μ g/mL, and against Cryptococcus neoformans and Aspergillus fumigatus with MIC values in the range of 0.25–2 μ g/mL. In addition, compounds A31 and A33 showed high metabolic stability in human liver microsomes in vitro , with the half-life of 80.5 min and 69.4 min, respectively. Moreover, compounds A31 and A33 showed weak or almost no inhibitory effect on the CYP3A4 and CYP2D6. The pharmacokinetic evaluation in SD rats showed that compound A31 had suitable pharmacokinetic properties and was worthy of further study. [Display omitted] • A novel class of 2-(benzo[ b ]thiophen-2-yl)-4-phenyl-4,5-dihydrooxazole derivatives was designed and synthesized. • Compounds A30 - A34 exhibited excellent broad-spectrum antifungal activities. • Compounds A31 and A33 showed weak inhibitory effect on CYP3A4 and CYP2D6. • Compound A31 showed high metabolic stability in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are significant contributors leading to many human health issues. Thus, this study was designed to perform chemical analysis and biological impact of airborne particulate matter 10 (PM 10) in the World heritage City of Kandy City in Sri Lanka. 12 priority PAHs and 34 metals, including 10 highly toxic HMs were quantified. The biological effects of organic extracts were assayed using an in vitro primary porcine airway epithelial cell culture model. Cytotoxicity, DNA damage, and gene expressions of selected inflammatory and cancer-related genes were also assessed. Results showed that the total PAHs ranged from 3.062 to 36.887 ng/m3. The metals were dominated by Na > Ca > Mg > Al > K > Fe > Ti, while a few toxic HMs were much higher in the air than the existing ambient air quality standards. In the bioassays, a significant cytotoxicity (p < 0.05) was observed at 300 μg/mL treatment, and significant (p < 0.05) DNA damages were noted in all treatment groups. All genes assessed were found to be significantly up-regulated (p < 0.05) after 24 h of exposure and after 48 h, only TGF-β1 and p53 did not significantly up-regulate (p < 0.05). These findings confirm that the Kandy city air contains potential carcinogenic and mutagenic compounds and thus, exposure to Kandy air may increase the health risks and respiratory tract-related anomalies. • First comprehensive analysis and exposure assessment supported by bioassays for airborne PAHs and heavy metals in Sri Lanka. • Few PAH and heavy metal levels in the Kandy city air are above maximum permissible levels. • The compounds in the Kandy city air have inflammatory, carcinogenic and mutagenic potentials. • Immediate attention is required to establish emission control and safeguard the quality of air in Kandy city, Sri Lanka. [ABSTRACT FROM AUTHOR]

l -amino alcohol derivatives exhibited high antifungal activity, but the metabolic stability of human liver microsomes in vitro was poor, and the half-life of optimal compound 5 was less than 5 min. To improve the metabolic properties of the compounds, the scaffold hopping strategy was adopted and a series of antifungal compounds with a dihydrooxazole scaffold was designed and synthesized. Compounds A33-A38 substituted with 4-phenyl group on dihydrooxazole ring exhibited excellent antifungal activities against C. albicans , C. tropicalis and C. krusei , with MIC values in the range of 0.03–0.25 μ g/mL. In addition, the metabolic stability of compounds A33 and A34 in human liver microsomes in vitro was improved significantly, with the half-life greater than 145 min and the half-life of 59.1 min, respectively. Moreover, pharmacokinetic studies in SD rats showed that A33 exhibited favourable pharmacokinetic properties, with a bioavailability of 77.69%, and half-life (intravenous administration) of 9.35 h, indicating that A33 is worthy of further study. [Display omitted] • A novel class of dihydrooxazole compounds was designed and synthesized. • Compounds A33 - A38 showed excellent antifungal activities. • The metabolic stability of compounds A33 and A34 was improved dramatically. • Compound A33 exhibited favourable pharmacokinetic properties in SD rats. [ABSTRACT FROM AUTHOR]