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Bloom-induced macroalgal enrichment on the seafloor can substantially facilitate dissolved sulfide (DS) production through sulfate reduction. The reaction of DS with sedimentary reactive iron (Fe) is the main mechanism of DS consumption, which however usually could not effectively prevent DS accumulation caused by pulsed macroalgal enrichment. Here we used incubations to investigate the performance of Fe-rich red soil for buffering of DS produced from macroalgae (Ulva prolifera)-enriched sediment. Based on our results, a combination of red soil additions (6.8 kg/m2) before and immediately after pulsed macroalgal deposition (455 g/m2) can effectively cap DS within the red soil layer. The effective DS buffering is mainly due to ample Fe-oxide surface sites available for reaction with DS. Only a small loss (4 %) of buffering capacity after 18-d incubation suggests that the red soil is capable of prolonged DS buffering in macroalgae-enriched sediments. [Display omitted] • Macroalgae decay on seabed stimulates quick generation of dissolved sulfide (DS). • Low red soil loads can effectively prevent DS release from macroalgae-rich seabed. • Low red soil loads can secure prolonged DS buffering in macroalgae-rich seabed. • Ample reaction Fe surface sites are the key for effective DS buffering by red soil. [ABSTRACT FROM AUTHOR]

Solid-phase speciation and porewater chemistry measured by the diffusive gradients in thin films (DGT) technique were used to understand the diagenesis of sulfur (S), iron (Fe), and phosphorus (P) in sediments of Jiaozhou Bay (China), which has been impacted by multiple anthropogenic perturbations. Despite water eutrophication, sediments of the bay are low in organic carbon and sulfide, but high in unsulfidized Fe(II). Dissimilatory iron reduction (DIR) prevails in sediments of the bay, and there is no evidence for responses of S and Fe diagenesis to the water eutrophication, which is largely attributable to unique depositional and diagenetic regimes in association with multiple anthropogenic perturbations. Good coupling of porewater Fe2+ and P in the porewaters suggests that P mobilization is driven mainly by DIR. Low Fe2+/P ratios in porewaters imply that oxidative regeneration of Fe oxides within the upper sediments is incapable of efficiently scavenging upward diffusing P. • Dissimilatory iron (Fe) reduction prevails in sediment of eutrophic Jiaozhou bay. • Diagenesis of sulfur (S) and Fe in the sediment is decoupled to water eutrophication. • Multiple anthropogenic perturbations have no net impacts on Fe and S diagenesis. • Phosphorus mobilization is mainly driven by reductive dissolution of Fe oxides. [ABSTRACT FROM AUTHOR]

Abstract Diagenesis of iron (Fe) and sulfur (S) in river-dominated marine systems is complex and has not been well documented. In this study, sediments from the Yellow River-dominated Bohai Sea (BHS) were used to examine the diagenesis of S and Fe and interpret it in light of anthropogenic disturbances. Organic carbon (OC) source characterization indicates that the bulk OC in the sediments is dominated by marine source (62.8 ± 9.4%). Based on low total reduced inorganic sulfide (TRIS) contents and abundant unsulfidized Fe(II), it is inferred that dissimilatory iron reduction (DIR) dominates over sulfate reduction (SR) in the sediments. DIR-dominated regimes and active physical reworking of the sediments are limiting SR and TRIS accumulations, resulting in a significant deviation of total OC (TOC) to TRIS ratio from that for typical marine sediments. Speciation of Fe and S indicates that, besides carbonate-associated Fe(II), other phases are also an important sink of unsulfidized Fe(II), and that reactive Fe is capable of quick buffering towards episodically produced dissolved sulfide on one month timescale. Pulsed sedimentation, seasonal sediment erosion, translocation, and sorting have exerted significant influences on the cycling of S and Fe, resulting in atypical patterns of Fe and S diagenesis. Nevertheless, there is no a discernable impact of eutrophication and algal blooms on geochemistry of the two elements in the sediments, which is ascribable to active physical reworking of sediments as well as the dilution of marine OC by rapid accumulation of terrestrial material. Highlights • Sedimentary organic carbonin the Bohai Sea is dominated by marine source • Dissimilatory iron reduction (DIR) exceeds iron oxide reduction by dissolved sulfide • DIR-dominated regimes and sediment resuspension limit sulfide accumulation • Sediment resuspension and pulsed input lead to atypical diagenesis of sulfur and iron • Terrestrial input and resuspension offset the impact of eutrophication on diagenesis [ABSTRACT FROM AUTHOR]

In marine sediments factors that influence iron (Fe) geochemistry and its interactions with other elements are diverse and remain poorly understood. Here we comparatively study Fe speciation and reactive Fe-bound organic carbon (Fe-OC) in surface sediments of the East China Sea (ECS) and the south Yellow Sea (SYS). The objectives are to better understand the potential impacts of geochemically distinct sediment sources and depositional/diagenetic settings on Fe geochemistry and OC preservation by Fe (hydr)oxides in sediments of the two extensive shelf seas around the world. Contents of carbonate- and acid-volatile-sulfide (AVS)-associated Fe(II) (Fe AVS + carb ) and magnetite (Fe mag ) in the ECS sediments are about 5 and 9 times higher, respectively, than in the SYS. This could be ascribed to the ferruginous conditions of the ECS sediments that favor the formation/accumulation of Fe carb and Fe mag , a unique feature of marine unsteady depositional regimes. Much lower total Fe(II) contents in the SYS than in the ECS suggest that lower availability of highly reactive Fe (Fe HR ) and/or weak Fe reduction is a factor limiting Fe(II) formation and accumulation in the SYS sediments. The ratio of Fe HR to total Fe is, on average, markedly higher (2.4 times) in the ECS sediments than in the SYS, which may be a combined result of several factors relevant to different sediment sources and depositional/diagenetic settings. In comparison with many other marine sediments, the percent fractions ( f Fe-OC ) of Fe-OC to total organic carbon (TOC) in the ECS and the SYS are low, which can be ascribed to surface adsorption of OC rather than coprecipitation or organic complexation as the dominant binding mechanisms. Based on the f Fe-OC in this study, total Fe-OC estimated for global continental shelves is equivalent to 38% of the atmospheric CO 2 pool, which indicates the important role of sorptive stabilization of Fe-OC in continental shelf sediments for buffering CO 2 release to the atmosphere. In the SYS, consistently less 13 C-depleted Fe-OC relative to 13 C of non-Fe-bound OC ( 13 C non-Fe-OC ) suggests selective sequestration of labile marine OC in the marine OC-dominated sediments of the central SYS. In the ECS, however, efficient oxidation of OC and frequent redox cycling of Fe in the unsteady depositional regimes may complicate the isotopic compositions of Fe-OC. A combination of our results and literature data demonstrates that Fe-OC contents are strongly dependent on the availability of TOC and reactive Fe, but the f Fe-OC is primarily controlled by the processes of Fe redox cycling in the sediments. [ABSTRACT FROM AUTHOR]

Dissolved sulfide, iron (Fe), and phosphorus (P) concentrations in sediments of the East China Sea were simultaneously measured in situ by diffusive gradients in thin films (DGT) technique. The results, by combination with solid-phase Fe speciation, were used to characterize the interplays of Fe, S and P. Diverse distributions of dissolved sulfide among the sites are attributable to highly dynamic diagenetic regimes and varying availability of labile organic carbon (OC). The DGT technique provided high-resolution evidence for coexistence of microbial iron reduction (MIR) and sulfate reduction in localized zones, and for Fe-coupled P mobilization. Measured Fe 2 + /P ratios suggest that Fe 2 + reoxidatiion at the oxic zones can serve as an efficient scavenger of P. Empirical estimation indicates that MIR plays an important role in anaerobic OC mineralization in the sediments, which is a combined result of low availability of labile OC, high reactive Fe content, and unsteady diagenetic regimes. [ABSTRACT FROM AUTHOR]

Sulfur isotopes and X-ray absorption near edge structure (XANES) spectroscopy were combined to characterize/compare three operational organic sulfur (OS) pools, i.e. fulvic acid sulfur (FA-S), humic acid sulfur (HA-S) and non-chromium reducible organic sulfur (non-CROS) in marine [the East China Sea (ECS) and Jiaozhou Bay (JZB)] vs. riverine [Yangtze River (YR) and JZB tributaries] sediments. XANES results indicate that in marine sediments high valency S was the dominant OS functionality in both HA-S and FA-S, while non-CROS was dominated by low valency OS (80–92%). In the riverine sediments FA-S was dominated by high valency OS, while the average fractions of low and high valency OS in HA-S were comparable. The isotopic composition of FA-S (δ 34 S FA-S ) and HA-S (δ 34 S HA-S ) indicated that a substantial fraction of sulfide was incorporated into FA via sulfurization in the marine sediments, whereas terrigenous OS was almost the sole important source of HA-S. Compared with the ECS sediments, JZB sediments had more depleted 34 S FA-S and a higher fraction of highly reduced FA-S due to eutrophication induced sulfurization. Relative to riverine FA-S, substantial sulfurization had not resulted in an increase in the fraction of highly reduced FA-S in marine sediments. This implies that the terrestrial systems may be much more favorable for the formation and/or preservation of highly reduced biogenic FA-S than the marine settings. The fraction of highly reduced HA-S in the JZB and its tributaries was similar, whereas the fraction was much lower in the ECS than in the YR. This indicates that highly reduced HA-S moieties in the YR may have been subject to extensive mineralization loss during transport in the large riverine/estuarine system, whereas the process in the JZB tributaries may be much weakened due to a relatively small catchment area. Distinct differences in isotopic and structural composition between humic-S (FA-S + HA-S) and non-CROS in the ECS sediments indicate that a combination of S isotopes and S-XANES is needed for characterizing the two operational pools for a better understanding the nature of OS in the ocean. [ABSTRACT FROM AUTHOR]

Anthropogenic perturbations exert important impacts on sulfur geochemistry in marine sediments. In the study, chemical extraction was used to quantify four sulfur pools, i.e., pyrite, humic-acid sulfur (HA-S), fulvic-acid sulfur (FA-S), and residual organic sulfur (ROS), in surface sediments of eutrophic Jiaozhou Bay. Results show that riverine inputs are the main control on organic matter (OM) distribution in the sediments. OM enrichment in the eastern coast is mainly due to discharges of anthropogenic wastes. Spatial coupling of pyrite and FA-S vs. TOC points to the impacts of OM enrichment on formation and preservation of pyrite and FA-S. Poor spatial coupling of HA-S vs. TOC is due to low fractions of diagenetic OS in the pool. ROS is mainly from riverine inputs and anthropogenic OS has been superimposed on this pool. Spatial coupling among TOC, pyrite-S and FA-S is a sensitive indicator of anthropogenic impacts on benthic processes of the bay. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reactivity of Fe oxides was quantified by the reactive continuum model. [•] Factors influencing Fe oxide reactivity and its variation were documented. [•] Spatial pattern of reactive Fe oxides is generally controlled by clay fraction. [•] Redox cycles caused a decrease in amount and reactivity of reactive Fe oxides. [Copyright &y& Elsevier]

In marine sediments, microbial mineralization of organic carbon (OC) proceeds through a cascade of pathways using different electron acceptors. Rates and relative importance of individual pathways can provide quantitative constraints on biogeochemical cycling of a number of elements, such as carbon, nitrogen, sulfur, iron, and manganese. However, such information is hitherto very scarce in the China marginal seas. To fill the gap, a multicomponent-coupled reaction-transport model CANDI was applied to quantify the rates and relative contributions of individual pathways of OC mineralization at three sites in the South Yellow Sea (SYS) sediments, based on which OC budgets were constructed. Model results at steady state generally well-reproduced the profiles of measured porewater solutes. The fast degrading OC pools G1 become exhausted over the upper 4 cm at the studied sites with the degradation rate constants k 1 ranging between 0.6 and 1.65 yr−1, while the slow degrading OC pool G2 remains almost undegradable on the timescales of the studied depth (∼25 cm) due to the low degradation rate constants k 2 (10−5‒10−4 yr−1) The depth-integrated rates of OC mineralization at the studied sites are in the range of 5.1–18.3 mmol C m−2 d−1, and aerobic respiration stands out as the dominant pathway, with its average contribution of 62%, followed by sulfate reduction (22.6%), dissimilatory manganese/iron reduction (8.4%), and denitrification (6.1%). Methanogenesis is a negligible process of OC mineralization within the studied depths. The contributions of aerobic respiration in the SYS sediments are much higher than the global average for marginal seas, but the contributions of sulfate reduction and iron dissimilatory reduction are much lower than their global averages, which could be ascribed to the low availability of degradable OC for anaerobic respiration. Budget of OC indicates that the mineralization and burial of OC in the muddy sediments account for 7.3 and 1.7%, respectively, of the total OC supplied to the sea, with the net OC accumulation efficiency of ∼19%. • Rates of organic carbon (OC) oxidation pathways are quantified by diagenetic modeling. • Aerobic respiration accounts for 62% of OC oxidation, being the dominant pathway. • Low availability of labile OC limits the anaerobic respiration pathways. • OC oxidization is oxidized at a rate of 9.8 mmol C m−2 d−1 in the muddy sediments. [ABSTRACT FROM AUTHOR]

Highlights: [•] Contents and sulfur isotopes of three organic sulfur (OS) forms are investigated. [•] Hydrolyzable OS is almost biological in origin and diagenetically refractory. [•] Terrigenous OS accounts for 77–79% of HA-S and sulfurization for 41–71% of FA-S. [•] Humic-acid S is generally inert in early diagenesis, but fulvic-acid S is reactive. [•] Low humic-sulfur in the sediment is due to a low extent of sulfurization. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Licorice (Glycyrrhiza uralensis roots) is used as a traditional medicine for the treatment of diabetes mellitus and its vascular complications. Glycyrrhizic acid (GA, also known as Glycyrrhizin), a triterpenoid saponin glycoside, is considered to be a bioactive component in Licorice and is beneficial to diabetic vascular complications. Aim of study: The present study was conducted to evaluate the potential protective activities on AGEs-induced endothelial dysfunction, including anti-apoptosis, antioxidant stress and anti-proinflammatory responses, and explore the underlying mechanism. Materials and methods: Human umbilical vein endothelial cells (HUVECs) were incubated and pre-treated with GA (10−9–10−6 M) or RAGE-Ab (5μg/ml) in the presence or absence of 200μg/ml AGEs. AO/EB fluorescence staining assay was performed to evaluate anti-apoptosis activity. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in cell supernatant were detected by kits while the intracellular reactive oxygen species (ROS) generation was determined by 2,7-dichlorodihydrofluorescin diacetate (DCFH-DA) kit. Immunocytochemistry analysis was designed to determine transforming growth factor beta1(TGF-β1) protein expression while immunofluorescence analysis for RAGE and NF-kB. The protein expressions of TGF-β1, RAGE and NF-kB were analyzed by Western blot analysis. Results: Pretreatment with GA at a concentration of 10−8–10−6 M significantly reduced the AGEs-induced apoptosis in HUVECs. GA significantly increased antioxidant enzyme SOD activity and decreased peroxide degradation product MDA level in a dose-dependent manner. Furthermore, GA also remarkably inhibited the overgeneration of AGEs-induced ROS. Both immunocytochemistry analysis and western blot analysis showed that GA significantly decreased the protein expression of poinflammatory cytokine TGF-β1 in a similar manner which RAGE-Ab did. Additionally, AGEs-induced RAGE and NF-kB protein expressions were down-regulated significantly by the pretreatment with GA or RAGE-Ab. Conclusion: These findings provide evidences that GA possesses protective activity on AGEs-induced endothelial dysfunction, including anti-apoptosis, anti-inflammation and antioxidant stress, via inhibiting RAGE/NF-kB pathway. GA might be an alternative for the prevention and treatment of diabetic vascular complications in an appropriate dosage. [ABSTRACT FROM AUTHOR]

Abstract: Solid-phase sulfur speciation and stable sulfur isotopic compositions are used to elucidate the formation and burial of pyrite-sulfur (Spy) and organic sulfur (OS) at three selected sites in mud sediments of the East China Sea (ECS) inner shelf, and to infer potential factors influencing the preservation of Spy and OS in the sediments. Our results in combination with previous studies show that the overall reactivity of sedimentary organic matter (OM) is low, while OM at the site impacted by frequent algal-bloom events displays somewhat enhanced reactivity. We observed characteristically low contents of acid volatile sulfide (AVS) and Spy in the sediments, which can be attributed to low sulfate reduction rate due to high redox potential together with limited availability of labile OM. Several geochemical features, for example, persistent occurrence of S0, good coupling among the profiles of AVS, S0 and Spy, and large 34Spy depletion, all suggest that the polysulfide pathway and disproportionation are likely involved in the pyrite formation. Organic sulfur amounts in the sediments are at the lower end of OS contents reported in many other marine sediments around the world. The sources of OS are both biosynthetic and diagenetic, with the biosynthetic OS being the major share (59–73%). In one site studied (C702), enhanced accumulation of OS within the upper layers (14cm) is believed to be associated with frequent algal-bloom events. Net burial fluxes of Spy and OS in the three sites studied range from 0.27 to 0.82mmol/m2/d and from 0.22 to 0.74mmol/m2/d, respectively. Sedimentation rate and algal-bloom events are two important factors influencing the spatial variability of Spy and OS burial fluxes in the whole shelf. [Copyright &y& Elsevier]

Summary: Background: Previous research has shown that innate immune system was more important than the acquired immune system in the pathogenesis of COPD. LL-37 is the only human cathelicidin identified so far. As an integral part of the innate immune system, besides antibacterial activity, its chemotactic activity, damage repairing, influencing apoptosis and its cytotoxicity are attracting people''s attention. The aim of the present study was to evaluate role of LL-37 in the pathogenesis of COPD. Methods: ELISA and immunohistochemistry were applied to investigate the expression of LL-37 in induced sputum and lung tissue of COPD patients. Bronchial epithelial cell (BEP2D) and alveolar epithelial cell (A549) were treated with LL-37 synthesis polypeptide in vitro to assess the role of LL-37 in inflammation and apoptosis. Results: We found that increased induced sputum levels of LL-37 in COPD patients were associated with airflow limitation, health status and exercise tolerance and the expressing intensity of LL-37 in both airway district and pulmonary alveoli area in COPD group significantly increased compared with control group. Through stimulation by CSE and LPS, the expression of LL-37 was increased in bronchial epithelial cell and alveolar epithelial cell. LL-37 synthesis polypeptide can promote the releasing of inflammatory factor IL-8 and induce apoptosis of bronchial epithelial cell and alveolar epithelial cell. Conclusion: This study suggested that LL-37 may play important role in the pathogenesis of COPD and may be a possible novel therapeutic target in COPD. [Copyright &y& Elsevier]

Abstract: Reactive iron (Fe) oxides in marine sediments play a critical role in removal of free sulfide. In this study, 0.5 and 6 N HCl-extractable Fe, acid volatile sulfide (AVS), and pyrite were examined in sediments at three sites of eutrophic Jiaozhou Bay to investigate the interactions of sulfur and Fe and possible influences of eutrophication on free sulfide removal. The results indicate that formation and accumulation of AVS and pyrite are limited by low availability of labile organic matter, despite eutrophication of the bay water. Quick buffering of free sulfide proceeded mainly via consumption of 0.5 N HCl-extractable Fe (labile Fe), however, the consumption did not result in a depletion of the Fe pool. High residual buffering capacity enables a quick removal of free sulfide in porewater, and thereby it is difficult for sulfide to accumulate and to cause detrimental effects on benthic organisms at the present steady state. Significant effects of eutrophication on Fe and sulfur geochemistry is restricted only to the estuarine sediments which were subject to direct wastewater discharges, whereas no such effects were observed in other sediments of the bay. [Copyright &y& Elsevier]

Abstract: Speciation and reactivity characterization of solid-phase Fe in marine sediments are of significance to understanding its heterogeneous mineralogy and crystallinity, the diagenetic cycling of Fe and its regulating roles on many other elements in sediments. In this study, a combination of sequential and single-step extractions was used for the determination of seven Fe pools in surface sediments of the East China Sea (ECS) continental shelf: (1) carbonate associated Fe (Fe(II)carb) plus acid volatile sulfide-Fe (Fe(II)AVS), (2) easily reducible amorphous/poorly crystalline Fe oxides (Feox1), (3) reducible crystalline Fe oxides (Feox2), (4) magnetite (Femag), (5) poorly reactive sheet silicate Fe (FePRS), (6) pyrite-Fe (Fepy), and (7) unreactive silicate Fe (FeU). Total Fe (FeT) in the sediments is largely determined by terrestrial aluminosilicate particles as indicated by a great similarity of the FeT with that of the Yangtze River and global riverine particulates. The size of FePRS is found to be the largest pool, followed by FeU, Feox2, Femag, Fe(II)AVS+carb, Feox1 and Fepy. The large FePRS may result from neoformation of Fe-rich clay minerals via reverse weathering and subsequent ageing. The small sizes of Fe(II)AVS+carb and Fepy pools is believed to be the result of low SO4 reduction due to generally low labile organic matter together with the oxic/suboxic, dynamic environments of the surface sediments. The occurrence of Feox1, Feox2 and FePRS in the sediments is closely associated with the clay fraction as indicated by a high spatial correlation between the former and the latter. Highly reactive Fe(FeHR) in the sediments is comparable to that in global marine sediments, but apparently lower than in the Yangtze River and global riverine particulates due probably to sequestration in the Yangtze Estuary. The ratios of FeHR/FeT, FePR/FeT and FeU/FeT in the ECS surface sediments consistently show more similarity to those in the Yangtze River particulates than in the global continental margin or deep-sea sediments. The surface sediments maintain a high level of buffering capacity toward sulfidation suggested by a large fraction of highly reactive Fe(III) oxides (Fe(III)HR) in FeHR. [Copyright &y& Elsevier]

Abstract: δ-MnO2 coatings on clay substrates tend to be poorer in crystallinity as compared with their discrete counterparts, which may be of environmental significance for adsorption and oxidation of contaminants. Discrete δ-MnO2 particles and three δ-MnO2-coated montmorillonite complexes with varying MnO2 loadings (4.8–34.9%) were synthesized, and oxidative decolorization of methylene blue (MB) by the synthetic materials was investigated in batch systems. Results showed that oxidative decolorization of MB increased with increasing loading of Mn-oxide coatings, whereas oxidation capacity of the coatings, on the basis of unit mass of MnO2, tended to decrease. Initial reaction rate of MB oxidation by both δ-MnO2 coatings and their discrete counterpart increased linearly with increasing Mn-oxide loadings, but the rate of the former was higher than that of the latter. An increase in humic acid concentration displayed a progressively enhanced promotive effect on MB decolorization, whereas the promotive effect was greatly suppressed at lower pH. [Copyright &y& Elsevier]

Pelagite generally has large surface area and high adsorbing and oxidizing reactivity due to highly amorphous nature, and high reducing potential of Mn (hydro)oxide phases present in it. In the present study, pelagite, collected from the East Pacific Ocean, was tested as a potential oxidant for decolorization of methylene blue (MB) in a batch system under air-bubbling and motor-stirring conditions. The effects of suspension pH (3.0–10.0), MB concentration (10–100mgL−1) and loading (0.2–3.0gL−1), and particle size (100–200mesh) of pelagite on kinetics of MB decolorization were assessed. Results show that in typical concentration range of dye wastewaters (10–50mgL−1), pelagite can be used as a highly efficient material for oxidative degradation of MB. MB decolorization was through a surface mechanism, that is, formation of surface precursor complex between MB and surface bound Mn(III, IV) center, followed by electron transfer within the surface complex. Iron (hydro)oxide phases present in the pelagite did not play an important role in MB decolorization. Suspension pH exerted double-edged effects on MB decolorization by influencing the formation of surface precursor complex, and reducing potential of the system. Kinetic rate of MB decolorization is directly proportional to saturation degree of available reaction sites by MB adsorption. At the initial and later stages, the kinetics for MB decolorization with respect to MB concentration, pelagite loading, and particle size could be described separately using two pseudofirst rate equations, except at very high pelagite loading (3.0mgL−1). Accumulation of Mn2+ and probably some organic intermediates exerted marked inhibitory effect on MB decolorization. Vigorous dynamic condition was favorable for MB decolorization. The presence of oxygen could enhance MB decolorization to a limited extent. [Copyright &y& Elsevier]

Alkaline white mud (AWM) has been investigated as a low-cost material for removal of an anionic dye, acid blue 80. The effects of contact time, initial pH of dye solution, AWM dosage, and the presence of inorganic anion sulphate or phosphate ion on removal of the dye were evaluated. The results show that AWM could be used as an effective material for removal of acid blue 80 in a pre or main process, particularly at high dye concentration (>300mgL−1), reaching maximum removal efficiency of 95%. At low dye concentration, surface adsorption is mainly responsible for the dye removal, while chemical precipitation of the dye anions with soluble Ca2+ and Mg2+ may play a dominant role for the dye removal at high concentration, producing much less sludge than conventional adsorption method. Solution pH has only a limited effect on the dye removal due to high alkalinity and large pH buffer capacity of AWM suspension and thereby pH is not a limiting factor in pursuing high dye removal. The presence of SO4 2− could reduce the dye removal by AWM only when SO4 2− concentration is beyond 0.7mmolL−1. The dye removal may be significantly suppressed by the presence of phosphate with increasing concentration, and the reduction in the dye removal is much larger at high dye concentrations than at low ones. [Copyright &y& Elsevier]

Abstract: In acidic soils and aquatic environments, polymeric hydroxyaluminum (HyAl) cations with various OH/Al ratios are ubiquitous. Hydroxyaluminum-montmorillonite (HyAl-Mt) complexes are widely distributed in acidic to slightly acidic soils and aquatic environments. The fixation of HyAl cations on Mt can significantly modify the mineralogical and electrochemical properties of the host clay, thereby substantially influencing adsorption/desorption and transport of many nutrients and pollutants. In the present study, HyAl-Mt complexes were synthesized through adsorption of polymeric HyAl cations with OH/Al ratio of 1.6 on Na-saturated Mt (Na-Mt). Interaction of F− with HyAl-Mt was investigated in acidic conditions and the environmental implications for F−-contaminated soils were also addressed. Results indicated that the effects of pH on F− sorption by HyAl-Mt were slight in the pH range of 5.0–9.0, whereas sorption increased rapidly with decreasing pH when pH was below 4.5. At initial pH >4.0, ligand exchange was the main mechanism for F− sorption. At initial pH 3.02 and high initial F− concentrations, several synergic mechanisms, such as coprecipitation, scavenging and surface adsorption were involved in F− removal from solution, which resulted in an abrupt and discontinuous increase in sorption capacity of HyAl-Mt for F− with increasing initial F− concentration, and a slight dependency of F− sorption on HyAl-Mt dosage. Compared with Na-Mt, sorption capacities of HyAl-Mt for F− were significantly enhanced by interlayering and coating with polymeric HyAl cations. HyAl-Mt would be important natural scavengers for F−. The presence of HyAl-Mt in acidic soils could greatly retard F− transport and bioavailability in soil environments. Interaction of F− with HyAl-Mt may mitigate acidification of F−-contaminated acidic soils. Application of synthetic HyAl-Mt may be one alternative for remediation of acidic F−-contaminated soils. [Copyright &y& Elsevier]

Abstract: A sampling-separation method and a dynamic monitoring method were used to investigate the time-dependent reactions of H+ ions with two contrasting types of soil, variable charge soils (VCS) and constant charge soils (CCS), by directly evaluating H+ ion consumption and other relevant consequences. The results for both CCS and VCS show that H+ ion consumption, increase in positive surface charge and increase in soluble Al are all characterized by a rapid step followed by a slow one. The higher the content of free Fe oxides in the soil, the larger the increase in positive surface charge and in H+ ion consumption in the initial rapid step. This is due mainly to protonation on external surfaces. The gradual increase in positive surface charge in the slow step for the 3 VCSs is a result of H+ ion diffusion to the reactive sites of ;OH on internal surfaces. The very low content of free Fe oxides on internal surfaces of the 2 CCSs render a negligible increase in positive surface charge in the slow step. For the 3 VCSs, the gradual consumption of H+ ions in the slow process is the result of protonation, Al dissolution and/or transformation into exchangeable acidity. For the 2 CCSs, however, the gradual consumption is mainly the result of Al dissolution and/or transformation into exchangeable acidity. The time-dependent Al dissolution from both VCS and CCS is influenced by several factors such as mineral components, solubility and dissolution rates of the soils, and H+ ion concentration in soil suspensions. [Copyright &y& Elsevier]

Carbon and oxygen isotopes were studied in fossiliferous Cambrian carbonates in northwestern Hunan Province (South China) and in northern Anhui and southern Shandong provinces (North China). Two major C isotope excursions related to biological events occur in the Wangcun section (Yongshun County, northwestern Hunan), which consists of a slope carbonate sequence (510 m thick) containing abundant trilobites. The first C isotope excursion (δ13C value shifts from –2.3‰ to 2‰) occurs near the boundary between the Qingxudong and Aoxi formations, close to the traditional Lower-Middle Cambrian boundary. The second excursion (δ13C value shifts from 0‰ to 3‰) occurs in the interval between the Linguagnostus reconditus Zone and the Glyptagnostus reticulatus Zone. The base of the G. reticulatus Zone define the base of the Paibi Stage and Furongian Series. Similar C isotope excursions also occur in shallow – water carbonate sections in North China. In Jiagou section near Huainan (Anhui Province), recently considered an important interval for defining the lower-middle Cambrian boundary because of dramatic changes in the trilobite fauna (extinction of redlichiids and appearances of ptychopariids), a negative C isotope excursion (δ13C value shifts from +1.21‰ to –1.93‰) occurs at the top of the lower member of the Mantou Formation. In the Gushan section (Changqing County, Shandong Province), a C isotope excursion (δ13C value shifts from –0.04‰ to 2.23‰) occurs at the base of the Changshan Formation and is coincident with the base of the Chuangia Zone. This excursion can be correlated with the excursion in the lower part of Glyptagnostus reticulatus Zone in the Wangcun section. The above two distinct C isotope excursions, which occur both in slope carbonates in South China and in shallow – water carbonates in North China, have also been recognized in Cambrian sections on other continents, and they coincide with global mass extinctions of trilobites. The two excursions evidently reflect global changes of Cambrian sea level, and they have utility for Cambrian subdivisions and for both regional and global stratigraphic correlation. In addition, a negative carbon excursion below the base of the Ptychagnostus atavus Zone in the Wangcun section supports previous suggestions that the FAD of P. atavus can be considered as a global correlatable horizon within the middle Cambrian. [Copyright &y& Elsevier]

Three-dimensionally preserved specimens of an indeterminate species of Sphenothallus Hall occur in limestones in the uppermost Guojiaba and lower Xiannudong formations (Qiongzhusian and early Canglangpuan stages, Lower Cambrian) in southern Shaanxi Province, China. The specimens consist of a small (up to 3 mm long), gradually tapered, subcircular to elliptic (transversely) tube that is broken at both ends, commonly with the fracture edge at the wide (apertural) end of each face forming a V- or U-shaped notch. Some specimens preserve the subconical upper (proximal) part of the holdfast, and all specimens are black. Combined scanning and transmission electron microscopy and energy dispersive elemental analyses show that the tube wall is finely laminated, with individual laminae measuring about 1 μm thick, and consists mainly of calcium phosphate but also contains organic material. Sphenothallus specimens from the Lower Cambrian Guojiaba and Xiannudong formations represent the earliest known record of this genus, and indicate that the origin of this taxon is coeval with and possibly related to the Early Cambrian bioradiation event. [Copyright &y& Elsevier]

The discoidal fossils identified as Stellostomites eumorphus Sun & Hou, Rotadiscus grandis Sun & Hou and Rotadiscus guizhouensis Zhao & Zhu are abundant in the Cambrian Chengjiang and Kaili Lagersta¨tten of southwest China. Reinvestigation of all available specimens of S. eumorphus and R. guizhouensis indicates that S. eumorphus has radiating lobe structures different from those of Eldonia ludwigi Walcott and has one additional set of dorsal radiating canals, and has a distinct central cavity, two characters that are not present in E. ludwigi. R. guizhouensis differs from R. grandis in the morphology of the disc, internal radiating lobes and tentacles. This supports the validity of the genus Stellostomites Sun & Hou, 1987, and substantiates the erection of a new genus, Pararotadiscus nov. gen., to receive Rotadiscus guizhouensis Zhao Zhu, 1994. Anatomical and taphonomical analyses indicate that S. eumorphus and P. guizhouensis were gregarious pelagic animals. The new anatomical information emphasize close phylogenetic relations with lophophorates (U-shaped intestine, circumoral tentacles and ectodermal, marginal accreted disc), though some features (e.g. dendritic tentacles, ventral pustules that may relate to reduced podia) do not exclude affinitics with echinoderms. [Copyright &y& Elsevier]

Natural processes and human activities exert important impacts on elemental cycling in coastal sediments, which has not been well documented. Sediments in the Bohai Sea and North Yellow Sea were investigated to assess the impacts of the Yellow River inputs and/or anthropogenic perturbations on diagenesis of iron and sulfur. Labile iron (0.5 M HCl-extractable iron) in the sediments is low due to iron-poor nature of source materials. Dynamic regimes and low availability of labile organic carbon (OC) result in relatively low sulfide contents in deltaic sediments. However, low but continuous supply of labile OC exported from an anthropogenically impacted bay could substantially elevate sulfide burial in sediments near the bay. Neither offshore oil exploitations nor frequent algal blooms in the seas have detectable influences on iron and sulfur diagenesis in the sediments. The sediments are capable of quickly consuming porewater sulfide by reaction with reactive iron under the current conditions. [Display omitted] • Availability of labile organic carbon is driving factor of sulfate reduction. • Labile iron is low in the sediment due to iron-poor nature of source materials. • Human perturbations have no significant impact on sulfur and iron diagenesis. • The Yellow River estuary exerts important influences on sulfur cycling. [ABSTRACT FROM AUTHOR]

Cycling and fates of iron (Fe) and sulfur (S) in marine sediments are influenced by depositional settings to differential extents. The information is crucial for addressing the responses of their benthic diagenesis to changing climates and environments and also for reconstructing paleo-depositional conditions, but has not been well constrained. Detailed chemical speciation was utilized to characterize geochemistry of Fe and S, and then to reveal the impacts of depositional settings on their diagenesis at three locations, representing contrasting depositional environments: (i) highly dynamic Yangtze River estuary (YRE), (ii) the depocenter of South Yellow Sea (SYS), which is only remotely impacted by large river, and (iii) the middle Okinawa trough (OT), a back-arc deep basin along the outer edge of the East China Sea (ECS) slope. Results show that the YRE sediments favor accumulation of total highly reactive Fe (Fe HR), while the SYS sediments are poor in Fe HR due to low Fe HR in their source material and/or preferential trapping of Fe HR during sediment transport through the semi-enclosed Bohai Sea. Ferruginous sediment regimes in the highly dynamic YRE system facilitate Fe(III) reduction and burial of unsulfidized Fe(II), while the SYS and OT sediments favor sulfate reduction and pyritization of Fe(II). Pyrite is always the main sink of reduced S that escapes reoxidation in the entire continental margin, regardless of depositional environments. Abundant reactive Fe(III) but low total reduced inorganic sulfide (TRIS) contents in the three sites suggest that TRIS burial is largely controlled by the availability of degradable OC and/or dynamic regimes of sediments. The applicability of two widely used Fe- and S-based proxies to distinguish bottom-water conditions, that is, OC/TRIS ratio and Fe HR to total Fe (Fe HR /Fe T) ratio, were examined in the three contrasting environments, and caveats were given for future applications of the two proxies. [Display omitted] • South Yellow Sea sediment is characterized by low content of reactive iron (RFe). • Dynamic estuaries favor accumulation of RFe and unsulfidized Fe(II). • Steady-state depositional conditions favor pyritization as the main sink of Fe(II). • Long-distance sediment transport to Okinawa Trough have no impact on RFe portioning. • Caveats are given for application of two iron- and sulfur-based paleo-proxies. [ABSTRACT FROM AUTHOR]

Chemoimmunotherapy is an emerging paradigm in the clinic for treating several malignant diseases, such as non-small cell lung cancer, breast cancer, and large B-cell lymphoma. However, the efficacy of this strategy is still restricted by serious adverse events and a high therapeutic termination rate, presumably due to the lack of tumor-targeted distribution of both chemotherapeutic and immunotherapeutic agents. Targeted drug delivery has the potential to address this issue. Among the most promising nanocarriers in clinical translation, liposomes have drawn great attention in cancer chemoimmunotherapy in recent years. Liposomes-enabled cancer chemoimmunotherapy has made significant progress in clinics, with impressive therapeutic outcomes. This review summarizes the latest preclinical and clinical progress in liposome-enabled cancer chemoimmunotherapy and discusses the challenges and future directions of this field. [Display omitted] [ABSTRACT FROM AUTHOR]

Marine sediments are the largest sink for organic carbon (OC) on Earth, and iron (Fe) oxides play an important role in stabilization of sedimentary OC. However, the roles of Fe oxides in OC stabilization during prolonged burial, for example, up to tens of thousands of years or more are still poorly constrained. In this study, we used traditional chemical extraction and near-edge X-ray absorption fine structure (NEXAFS) spectroscopic technique to characterize bulk OC and Fe-associated OC (Fe-OC) through depth in gravity cores collected from three sites near the Yangtze River Estuary (YRE), in the South Yellow Sea (SYS), and in the middle Okinawa Trough, which have contrasting depositional environments. Results show that depositional environments have exerted quite different influences on sources and burial of sedimentary OC, and thus on OC degradation during prolonged burial at the three sites. Reactive Fe (Fe R) contents at the three sites are greatly influenced by sediment sources, the history of its transport, and its reworking intensity, with Fe R contents near the highly dynamic YRE much higher than at the central SYS and the middle Okinawa Trough. The fractions of Fe-OC in total OC (f Fe-OC) displayed no clear or consistent trends with depth or by site, probably due to the dual roles of Fe redox cycling in OC protection versus its oxidation. As indicated by the f Fe-OC , reactive Fe plays a limited role in OC preservation in margin sea sediments of East China. A combination of NEXAFS spectra and isotopic compositions of bulk OC and Fe-OC indicates that main OC functionalities have not experienced differential alterations and/or no specific OC moieties have been selectively stabilized/released during prolonged burial in the three contrasting depositional environments. • Depositional regimes control sources and burial of sedimentary organic carbon (OC). • Sediment source, transport history and reworking intensity affect Fe R contents. • There is no clear selectivity of OC retention by reactive iron (Fe R) along depth. • Fe R plays limited roles in OC preservation in sediments of east China margin seas. [ABSTRACT FROM AUTHOR]

• Wedelolactone, a natural compound, shows outstanding effects of anti-inflammation and anti-oxidative stress. • The alleviation to doxorubicin(DOX)-driven podocyte injury may contribute to the attenuation of renal damage. • Wedelolactone can regulate the IκK/IκB/NF-κB signaling pathway to alleviate levels of oxidative stress and inflammation. The acute kidney injury(AKI) caused by nephrotoxic drugs contributes to inflammation and oxidative injury in podocytes. Wedelolactone (WED), a natural compound, is found with activities as anti-inflammation, anti-oxidative, anti-free radical,and etc. In this present study, MPC-5 cells were exposed to the nephrotoxic drugs doxorubicin (DOX). The results showed that WED significantly increased the SOD activity, CAT and GSH-Px levels, while significantly decreased the MDA content and ROS levels in DOX-induced MPC-5 cells. WED could also significantly decrease the levels of cytokines IL-6, MCP-1, TNF-α, and TGF-β1. Additionally, the activation and phosphorylation of IκKα, IκBα and NF-κB p65 was inhibited by WED. The co-treatment of PDTC (NF-κB inhibitor) and WED significantly reduced NF-κB p65 phosphorylation. These findings suggested that WED alleviated inflammation and oxidative stress of doxorubicin-induced MPC-5 cells through IκK/IκB/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to explore the different expression of L-PGDS (lipocalin-type prostaglandin D synthase) in rat epididymidis and to gain further insight into the potential function of L-PGDS in male reproduction. The expression of L-PGDS in rat epididymidis was assessed using real-time quantitative PCR and immunoblotting. The distribution of L-PGDS in rat epididymidis was explored by immunohistochemical methods. The result of immunohistochemistry displayed that L-PGDS was mainly distributed in epididymidis and localized within the cytoplasm and the cilia of the epithelial cells. Real-time quantitative PCR and immunoblotting showed that L-PGDS was strikingly expressed in the caput epididymidis, while a moderate to weak expression was observed in the corpus and cauda epididymidis, the level of mRNA was 0.52±0.02 in the caput, 0.48±0.03 in the corpus and 0.32±0.01 in the cauda epididymidis, the level of protein expression in caput, corpus and the cauda groups was 1, 0.89±0.03 and 0.62±0.01, which suggested that L-PGDS may play certain kind of role during the process of the spermatozoa maturation. [Copyright &y& Elsevier]

The diagenetic interplays of organic carbon (OC), sulfur (S), and iron (Fe) in marine sediments and their responses to changes in depositional and climatic conditions are poorly characterized. In this study, chemical speciation and isotopes were combined to characterize diagenesis of OC, S and Fe in sediments of the middle Okinawa Trough (OT), a back-arc deep basin along the edge of the East China Sea outer shelf, since the Last Glacial Maximum (LGM). Two key geochemical proxies, i.e., OC/pyrite-S ratios and the degrees of pyritization, indicate anoxic bottom-water conditions during the last Glacial/Deglacial, which promoted burial of OC and pyrite. However, a shift to oxic conditions during the Deglacial-Holocene transition facilitated aerobic respiration, resulting in lower burial of OC and pyrite. In contrast to previous studies, the environmental changes induced by large sea-level rises since the LGM have not triggered significant variations in pyrite-S isotopic compositions, probably due to persistently low sedimentation rates. Variable extents of Fe enrichment are identified in the sediments since the LGM, with lower enrichment during the Holocene probably due to increased distance of Fe shuttling and concomitant Fe ageing. Anoxic bottom water during the Glacial/Deglacial did not induce an expected intensification of OC sulfurization, probably because sedimentary Fe enrichment favored pyrite formation but competitively dampened OC sulfurization. Lines of geochemical evidence hint at a discontinuous deposition at ~200 cm depth probably caused by mass wasting. • Bottom water redox regimes exert major controls on diagenesis in the Okinawa Trough. • Anoxic bottom water is critical for high burial of organics during the last Glacier. • Iron shuttled from the East China Sea shelf is enriched in the Okinawa Trough. [ABSTRACT FROM AUTHOR]

The influence of differential chemical weathering intensity on the contents and spatial distribution of highly reactive iron (Fe HR) in the marginal sea sediments is not well documented. Here, we used sequential extractions to quantify various Fe pools in offshore surface sediments of the northern South China Sea (nSCS), which receives multiple fluvial sediments with distinct chemical weathering intensity, and then to unravel whether and if so, to what extent, the contents and spatial distributions of Fe HR are linked to chemical index of alternation (CIA) of the sediments. Our results show that, despite the inputs of Fe HR -rich, highly chemically weathered fluvial sediments, Fe HR contents in offshore sediments of the nSCS are almost independent of the CIA values, and Fe HR was not enriched relative to the global average of Fe HR in oxic sediments, probably due to effective trapping of Fe HR in the estuary and dilution by moderately chemically weathered Taiwan-sourced sediments. Our results indicate that the signature of Fe HR enrichment previously observed in the offshore sediments, which are discharged from a highly chemically weathered mountainous island (Hainan Island) of the nSCS, becomes lost beyond the local zone around the island. Relative to the marginal sediments of the nSCS (water depth <1000 m), the higher Fe HR contents in the deep-water sediments (water depth larger than 1000 m) can be attributed to higher smectite contents, lower inorganic carbon contents, and low dilution by Taiwan-sourced fluvial material in the deep-water area. A comparison of the subtropical nSCS and the temperate East China Sea indicates that chemical weathering intensity is not the overarching factor governing Fe HR /Fe T ratios in the two climatically different regions, though chemical weathering intensity along with depositional/diagenetic regimes is an important factor controlling the sizes and transformation of some specific Fe HR pools. • Reactive Fe (Fe HR) enriched by chemical weathering is restricted to local zone. • Chemical weathering intensity has minor effect on Fe HR content in offshore sediment. • Sediment sources, sorting, and depositional/diagenetic regimes impact Fe HR and CIA. [ABSTRACT FROM AUTHOR]