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Antibiotics have been identified as obesogens contributing to the prevalence of obesity. Moreover, their environmental toxicity shows sex dependence, which might also explain the sex-dependent obesity observed. Yet, the direct evidence for such a connection and the underlying mechanisms remain to be explored. In this study, the effects of tetracycline, which is a representative antibiotic found in both environmental and food samples, on Drosophila melanogaster were studied with consideration of both sex and circadian rhythms (represented by the eclosion rhythm). Results showed that in morning-eclosed adults, tetracycline significantly stimulated the body weight of females (AM females) at 0.1, 1.0, 10.0 and 100.0 µg/L, while tetracycline only stimulated the body weight of males (AM males) at 1.0 µg/L. In the afternoon-eclosed adults, tetracycline significantly stimulated the body weight of females (PM females) at 0.1, 1.0 and 100.0 µg/L, while it showed more significant stimulation in males (PM males) at all concentrations. Notably, the stimulation levels were the greatest in PM males among all the adults. The results showed the clear sex dependence of the obesogenic effects, which was diminished by dysrhythmia. Further biochemical assays and clustering analysis suggested that the sex- and rhythm-dependent obesogenic effects resulted from the bias toward lipogenesis against lipolysis. Moreover, they were closely related to the preference for the energy storage forms of lactate and glucose and also to the presence of excessive insulin, with the involvement of glucolipid metabolism. Such relationships indicated potential bridges between the obesogenic effects of pollutants and other diseases, e.g., cancer and diabetes. [Display omitted] [ABSTRACT FROM AUTHOR]

The phased-array-based ultrasonic full-matrix imaging of carbon fibre-reinforced polymer (CFRP) laminates with total focusing method (TFM) is promising yet challenging due to the layered configuration and strong anisotropy. Traditionally, the precise a priori knowledge of ultrasonic ray paths in anisotropic CFRP laminates are required for accurate TFM imaging, making the inspection process complicated and time consuming. In this work, an adaptive ultrasonic-imaging method is proposed for arbitrarily anisotropic CFRP laminates through full-matrix capture (FMC) and TFM. Firstly, the elastic constants are derived from the FMC data, upon which the 3D group-velocity profiles of ultrasonic waves in CFRP laminates with arbitrary stacking sequences can be calculated. The anisotropic effect is then adaptively corrected for TFM. To verify the effectiveness of proposed method, simulations and experiments are conducted on different anisotropic CFRP laminates with mimicked defects, such as delamination, cracks, voids, etc. The simulated and experimental results well agree with each other, indicating that the proposed method can accurately reconstruct the internal defects of different types. This work provides a convenient and comprehensive avenue towards the ultrasonic inspection of arbitrarily anisotropic CFRP laminates, which markedly benefit the quality control of CFRP components in various fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Water-borne erythromycin (ERY) increased triglycerides with inhibition on lipolysis. • Dietary ERY increased triglycerides with lipolysis-inhibition and lipogenesis-stimulation. • ERY's effects involved insulin and nhr-49 signaling pathways. • ERY disturbed bacterial colonization in intestines and intestinal barrier permeabilities. • ERY affected fatty acid composition (especially SCFAs) in bacteria and nematodes. As emerging pollutants, antibiotics were widely detected in water bodies and dietary sources. Recently, their obesogenic effects raised serious concerns. So far, it remained unclear whether their obesogenic effects would be influenced by water- and diet-borne exposure routes. In present study, Caenorhabditis elegans , nematodes free-living in air–water interface and feeding on bacteria, were exposed to water- and diet-borne erythromycin antibiotic (ERY). The statuses of the bacterial food, inactivated or alive, were also considered to explore their influences on the effects. Results showed that both water- and diet-borne ERY significantly stimulated body width and triglyceride contents. Moreover, diet-borne ERY's stimulation on the triglyceride levels was greater with alive bacteria than with inactivated bacteria. Biochemical analysis showed that water-borne ERY inhibited the activities of enzymes like adipose triglyceride lipase (ATGL) in fatty acid β-oxidation. Meanwhile, diet-borne ERY inhibited the activities of acyl-CoA synthetase (ACS) and carnitine palmitoyl transferase (CPT) in lipolysis, while it stimulated the activities of fatty acid synthase (FAS) in lipogenesis. Gene expression analysis demonstrated that water-borne ERY with alive bacteria significantly upregulated the expressions of daf-2 , daf-16 and nhr-49 , without significant influences in other settings. Further investigation demonstrated that ERY interfered with bacterial colonization in the intestine and the permeability of the intestinal barrier. Moreover, ERY decreased total long-chained fatty acids (LCFAs) in bacteria and nematodes, while it decreased total short-chained fatty acids (SCFAs) in bacteria but increased them in nematodes. Collectively, the present study demonstrated the differences between water- and diet-borne ERY's obesogenic effects, and highlighted the involvement of insulin and nhr-49 signaling pathways, SCFAs metabolism and also the interaction between intestinal bacteria and the host. [ABSTRACT FROM AUTHOR]

Abstract In the present work, we analyzed the concentration patterns of 20 Polycyclic Aromatic Hydrocarbons (PAHs) in 25 surface sediments and 11 sediment cores from the northern part of Taihu Lake, China. Three of the cores were dated based on 137Cs activity for the deposition age of the sediment. The spatial distributions of the PAH concentrations show that the inflow rivers into Zhushan Bay and Meiliang Bay were the main pathway for PAHs and sediment input to the northern part of the lake. This results in substantially higher PAH concentrations (up to 5000 ng/g) and sedimentation rates (higher than the average of 3–4 mm/a) in the area close to the river outlets. In addition, results also show that PAH concentrations in the sediments considerably increased from the early 1960s, but the decreasing concentrations in the upper layers of the sediment could be attributed to the introduction of measures on environmental improvement from ca. 2000. There were both anthropogenic and biogenic origins of perylene in the lake sediments, which were distinguished based on spatial distribution patterns and also the concentration proportions of perylene to the sum of the 20 PAHs. In the cores collected close to river outlets, the concentration proportions of perylene typically range from 0.02 to 0.18 and there are significant positive linear correlations between the concentration of perylene and three anthropogenic PAHs (Benzo[a]pyrene, Benzo[e]pyrene, Pyrene), suggesting that perylene was dominated by anthropogenic input. However, the cores collected further away from the river outlets show the concentration proportions between 0.13 and 0.96, and present significant negative correlations or no correlations between perylene and the three PAHs, suggesting that perylene was mainly formed by biogenic activities. Furthermore, the different perylene sources accompanied with the location distributions imply that anthropogenic activities could inhibit its biogenic formation. Graphical abstract Image 1 Highlights • River inflows are the main pathway for PAHs and particles input in the northern part of Taihu Lake. • Anthropogenic activities significantly influenced the PAH abundance in the lake sediment. • Perylene originated from anthropogenic and biogenic activities in different sampling areas. This study provides an insight of anthropogenic impacts on PAH deposition in the sediment of Taihu Lake and also clearly distinguishes biogenic and anthropogenic origins of perylene in the sediment. [ABSTRACT FROM AUTHOR]

Abstract Negative effects of environmental antibiotics on non-target organisms were observed in studies at various levels of the biological organization. Yet, studies combining the effects at multiple levels were required to interpret their ecological frequencies in a broader context. Currently, effects of sulfamethoxazole (SMX) was studied on the amphipod Hyalella azteca which is important in ecological stability. At the biochemical level, effects on the antioxidant capacities showed stimulation with an inverse U-shaped change over the concentrations. The stimulation was greater in male than in females. Effects on the oxidative stress showed a U-shaped change which included stimulation and inhibition in males, and solely stimulation in females. The stimulation was less in males than in females. Effects on acetylcholinesterase (AChE) activities in both sexes were well correlated with those on oxidative stress (p < 0.05). At the individual level, effects on the body weight showed an inverse U-shaped change over concentrations, and the stimulation was greater in males than in females. The stimulations were significantly correlated with the male oxidative stress (p < 0.01), and male (p < 0.1) and female AChE activities (p < 0.05). Effects of SMX on the pre-copulation behavior also showed an inverse U-shaped change which correlated with male and female antioxidant capacities (p < 0.05) and the male body weight (p < 0.05). At the population level, effects on the reproduction showed an inverse U-shaped change over concentrations, and they significantly correlated with the male body weight (p < 0.05) and the pre-copulation behavior (p < 0.05). Summing up, SMX provoked simultaneous disturbances on the amphipod at multiple levels with sex-dependent responses. Graphical abstract Image 1 Highlights • Effects of sulfamethoxazole was studied on the amphipod Hyalella azteca. • Disturbances on pre-/anti-oxidant status were greater in males than in females. • AChE activity changes, greater in males, were correlated with oxidative stress. • Stimulation and inhibition on male growth were greater than those on females. • Stimulation on reproduction were well correlated with pre-copulation behavior. Sulfamethoxazole caused sex-dependent effects on pro-/anti-oxidant status, AChE activities, and growth, and stimulated behavior and reproduction in Hyalella azteca. [ABSTRACT FROM AUTHOR]

Abstract Adverse effects of sulfonamide antibiotics (SAs) include growth inhibition and antioxidant activation which showed trade-off effects. Yet, the influence of food availability on such effects have not been thoroughly investigated. Caenorhabditis elegans were exposed to four SAs at high and low food availabilities which were represented by the optical densities of bacteria at 600 nm. The nematode feeding, growth and antioxidants including superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) were determined. Results showed that the control nematodes at low food availability had less growth and greater antioxidant responses than the nematodes at high food availability. In SA exposure, the nematode growth in the presence of food (at both high and low food availability) was less than that in its absence, supporting the role of food as an exposure pathway. The nematode growth at low food availability showed significantly greater inhibition than at high food availability (p < 0.05). The nematode antioxidants showed stimulations, and CAT had the greatest stimulation. Moreover, the stimulation on CAT at low food availability were significantly higher than those at high food availability (p < 0.05). That is to say, SA exposure at low food availability further biased the trade-off effects towards more energy investment in antioxidant with less in growth. Further studies on the expression levels of CAT encoding genes demonstrated that cells in intestines were the main antioxidant response sites, which further supported the contributions of food to the observed toxicities. Highlights • In controls, low food availability caused trade-off between growth and antioxidants. • Sulfonamide exposure at low food availability biased trade-off toward antioxidants. • Sulfonamide exposure with food inhibited growth more than without food. • Sulfonamides stimulated intestinal catalase at high and low food availability. [ABSTRACT FROM AUTHOR]

Abstract Influences on lipid metabolism and multi-generational obesogenic effects raised new concerns on lipophilic pollutants (e.g., lindane). Yet, the mechanisms remained unanswered. The present study exposed Caenorhabditis elegans to lindane for 4 consecutive generations (F0 to F3) at 1.0 ng/L, and measured effects in the directly exposed generations (F0 to F3), indirectly exposed ones (T1 and T1′) and un-exposed ones (T3 and T3′). Lindane stimulated fat storages in all generations. At the biochemical level, lindane stimulated both acetyl-CoA carboxylase (ACC) and carnitine palmitoyl-transferases (CPT) in F0, T1 and T2, while inhibited them in F3, T1′ and T3′, demonstrating the balance between fatty acid synthesis and its depletion toward fat accumulation over generations. Moreover, lindane caused different effects on insulin among generations. It inhibited insulin in F0 and F3 and exhibited consistent effects on the expression changes of daf-2 , sgk-1 and daf-16 genes in insulin-like signal pathway. Lindane also inhibited insulin in T1 and T3 but exhibited consistent effects on the expression changes of daf-2 , akt-1 and daf-16. Different roles of sgk-1 and akt-1 indicated the response strategies from tolerance (F0 and F3) to avoidance (T1 and T3). Lindane stimulated insulin in T1′ and T3′ and exhibited consistent effects on expression changes of daf-2 , sgk-1 and daf-16 genes that were similar in F0 and F3. Highlights • Multigenerational obesogenic effects of lindane were studied on C. elegans. • Lindane stimulated fat storages in F0, F3, T1, T3, T1′ and T3’. • Fat storage stimulation was due to greater fatty acid synthesis than its oxidation. • Lindane inhibited insulin in F0, F3, T1 and T3, but stimulated them in T1′ and T3’. • Insulin changes were consistent with expressions of daf-2 , sgk-1 / akt-1 and daf-16. [ABSTRACT FROM AUTHOR]

The redox state of NADH/NADPH balance (nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate) is crucial in cellular homeostasis. Recent studies reported that sodium halide ions (NaX, X = F − , Cl − , Br − and I − ) stimulated NAD(P)H in Vibrio fischeri (VF). However, it remained unanswered whether this pattern applied in salts with other cations, e.g. , K + , Mg 2+ and Ca 2+ , whose aquatic concentrations were increased by anthropogenic activities and climate change. Currently, VF were incubated with chloride salts, including KCl, MgCl 2 and CaCl 2 , and effects were measured in a time-dependent fashion. Both NADH and NADPH showed stimulation that increased over time, and the greatest maximum stimulation at 24 h was CaCl 2  > MgCl 2  > KCl. The changes of NADH/NADPH ratios over time in CaCl 2 , MgCl 2 and KCl were descendent, ascendant and stable, respectively. Simultaneously, FMN:NAD(P)H reaction catalyst (luciferase, in the form of expression levels of lux A and lux B), adenosine triphosphate and the expression levels of its regulating gene adk were also stimulated. The luminescence showed even more significant stimulations than the overall redox reaction. Together with earlier reported effects of NaCl, the chloride salts commonly disturbed the redox state and influenced the adaption of organisms to challenging environments. [ABSTRACT FROM AUTHOR]

The excess of halide ions (F − , Cl − , Br − , I − ) can cause adverse effects. Earlier studies demonstrated time-dependent stimulations of organic salts with halide ions on photobacteria. Therefore, inorganic ones with halide ions ( e.g. , NaX, X = F − , Cl − , Br − , I − ) were assumed to cause similar effects. In the present study, Vibrio fischeri was exposed to NaX. Results showed that the contents of favin mono-nucleotide (FMN), nicotinamide adenine dinucleotide (NADH), and nicotinamide adenine dinucleotide phosphate (NADPH) were stimulated by NaX with a time-dependent fashion. The maximum stimulations on FMN at 24 h were 172%, 168%, 211% and 298% of the control (p < 0.05) in NaF, NaCl, NaBr and NaI, respectively, with an order of NaF ≈ NaCl < NaBr < NaI. The maximum stimulations on NAD(P)H at 24 h followed similar orders. Similar time-dependent stimulatory effects were observed in the FMN:NAD(P)H reaction catalyst (luciferase, in the form of expression levels of lux A and lux B), adenosine triphosphate and the expression levels of its regulating gene adk . The luminescent stimulations were significantly higher than the biochemical ones despite of similar time-dependence and stimulation order among NaX. The overall results showed a common hormetic pattern in sodium halide salts. [ABSTRACT FROM AUTHOR]

Taking current situation of energy regarding winter heating and study on heating as an example, this paper is based on field measurement, investigation and study, discussing the current energy consumption and usage of winter heating of rural areas in Shandong Province, China. The paper reveals that the most regions in Shandong are utilizing furnaces to keep warming which is a relatively primitive method. Most of villagers are satisfied with the indoor environment although this is not the case, which is contributed by the farmers’ strong passive adaptability. With the constant improvement in living standard of Shandong rural people, simultaneously, energy quality and quantity are required higher and higher. Traditional biomass energy cannot meet their needs. Therefore, more effective and cleaner energy are necessary for them to advance daily living quality and level. The heating measure that will save more energy should be adopted. [ABSTRACT FROM AUTHOR]

A toxicity database of over 157 ionic liquids (ILs) was established on Vibrio fischeri (VF). The database contained mainly monotonic concentration-response relationship, and its application in risk assessment was challenged by potential non-monotonic hormetic effects of ILs. In the present study, the hormetic effects of 1-ethyl-3-methylimidazolium salts ([emim]X, X = BF 4 , Cl and Br) were confirmed on VF, and biochemical explanations were explored in a time-dependent manner. On luminescence, [emim]BF 4 showed inhibitory effects compared with the control, and the median effective concentration (EC 50 ) increased from 3.15E-02 to 8.88E-02 mol/L from 0.25 to 24 h. Notably, [emim]BF 4 also showed stimulatory effects at 18 h when the maximum stimulation (E min ) was 51.8% higher than the control, and at 24 h when the E min increased to 120% higher than the control. Compared with [emim]BF 4 , [emim]Cl had higher EC 50 values which increased over time, while it had less maximum stimulation which also increased over time. In results of [emim]Br, there were only inhibitory effects. At the biochemical level, the stimulatory effects of [emim]BF 4 and [emim]Cl on triphosphopyridine nucleotide (NADPH) and nicotinamide adenine dinucleotide (NADH) were earlier than those on luminescence. Moreover, NAD(P)H showed stimulation in [emim]Br which did not have hormetic effects on luminescence. Meanwhile, the effects of [emim]X on flavin mononucleotide, adenosine-triphosphate, reactive oxygen species, superoxide dismutase, catalase, reduced glutathione and lipid peroxidases showed consistent time-dependent changes with those on luminescence. The results indicated different roles between NAD(P)H and other biochemical indices, e.g., the antioxidant responses, in the stimulation of [emim]X on luminescence. [ABSTRACT FROM AUTHOR]

Environmental obesogens contributed significantly to the obesity prevalence. Recently, antibiotics joined the list of environmental obesogens, while the underlying mechanisms remained to be explored. In the present study, effects of erythromycin (ERY), one widely used macrolide antibiotic, were measured on C. elegans to investigate the obesogenic mechanism. Results showed that ERY at 0.1 μg/L significantly increased the fat content by 17.4% more than the control and also stimulated triacylglycerol (TAG) levels by 25.7% more than the control. Regarding the obesogenic mechanisms, ERY provoked over-eating by stimulation on the pharyngeal pumping and reduction on the satiety quiescence percentage and duration. Such effects were resulted from stimulation on the neurotransmitters including serotonin (5-HT), dopamine (DA) and acetylcholine (ACh). The nervous responses involved the up-regulation of Gsα (e.g., ser-7 , gsa-1 , acy-1 and kin-2) signaling pathway and the down-regulation of TGFβ (daf-7) but not via cGMP-dependent regulations (e.g., egl-4). Moreover, ERY stimulated the activities of fatty acid synthase (FAS) and glycerol-3-phosphateacyl transferases (GPAT) that catalyze lipogenesis, while ERY inhibited those of acyl-CoA synthetase (ACS), carnitine palmitoyl transferase (CPT) and acyl-CoA oxidase (ACO) that catalyze lipolysis. The unbalance between lipogenesis and lipolysis resulted in the fat accumulation which was consistent with up-regulation on mgl-1 and mgl-3 which are the down-steam of TGFβ regulation. Such consistence supported the close connection between nervous regulation and lipid metabolism. In addition, ERY also disturbed insulin which connects lipid with glucose in metabolism. [Display omitted] • ERY caused fat accumulation and showed obesogenic effects. • ERY provoked over-eating and reduced satiety percentage and duration. • ERY stimulated neurotransmitters and disturbed the Gsα and TGFβ regulations. • ERY biased toward lipogenesis against lipolysis. • Obesogenic effects of ERY also involved glucolipid metabolism via insulin. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a novel MgAl2O4 spinel whisker reinforced composite was synthesized in situ in an Al matrix by a powder metallurgy technique. In MgAl2O4/Al composite, the whisker content was varied from 3% to 15% in weight and each one was completely investigated. The as-produced MgAl2O4/Al composites were hot extruded and MgAl2O4/Al composites rods with high relative density were obtained. Both the hardness and the softening temperature of the composites increased with increasing content of MgAl2O4 whisker. The dilatometric measurements show that MgAl2O4 whisker reinforced Al composites exhibit better thermal stability and lower thermal expansion coefficient than aluminum alloys. Moreover, wear resistance is also enhanced due to the formation of the whisker-formed network structure which is capable of bearing and transferring abrasion effect. Thus, the enhanced properties of the composites could be obtained. [Copyright &y& Elsevier]

Abstract: Single-crystal aluminum borate (Al4B2O9) nanowhiskers with diameters from 20 to 200nm have been synthesized on the surface of aluminum powder at relatively low temperatures after high energy ball-milling pretreatment. It was found that the reaction temperature plays an important role in determining the diameter and length of the single-crystal Al4B2O9 nanowhiskers. The growth of the nanowhiskers can occur at a low temperature of 650°C due to the ball-milling pretreatment. The growth mechanism of the nanowhiskers is considered to be the solution–liquid–solid (SLS) growth. Our in-situ growth of nanowhiskers on the aluminum matrix is an effective way to prepare Al4B2O9 nanowhisker/aluminum composite powders with homogenous distribution of the reinforcement. [Copyright &y& Elsevier]

The combined effects of titanium dioxide (TiO2) nanoparticles and humic acid (HA) on the bioaccumulation of cadmium (Cd) in Zebrafish were investigated. Experimental data on the equilibrium Cd bioaccumulation suggest that only the dissolved Cd effectively contributed to Cd bioaccumulation in HA solutions whereas both the dissolved and TiO2 associated Cd were accumulated in TiO2 or the mixture of HA and TiO2 solutions, due likely to the additional intestine uptake of the TiO2-bound Cd. The equilibrium Cd bioaccumulation in the mixed system was comparable to that in the corresponding HA solutions, and significantly lower than that in the corresponding TiO2 solutions (n = 3, p < 0.05). The presence of either HA or TiO2 (5–20 mg L−1) in water slightly increased the uptake rate constants of Cd bioaccumulation whereas combining HA and TiO2 reduced the uptake rate constants. [Copyright &y& Elsevier]

Short-chained perfluorobutane sulfonate (PFBS, four-carbon) and perfluorohexane sulfonate (PFHxS, six-carbon) are widely employed to substitute long-chained per- and poly-fluoroalkyl substances (PFASs). Recent studies showed the potential persistence of PFBS and PFHxS, and also reported their correlation with obesity. However, the long-term outcome and underlying mechanisms remained poorly understood. Presently, the effects of PFBS and PFHxS were studied on C. elegans with multi- and trans -generational experiments. The multi-generational effects were measured in continuous four generational exposure (i.e., F1 to F4). Results showed that PFBS did not stimulate the fat content in F1 but in F4 with continuous but different disturbances on the lipid metabolism and the insulin and insulin-like (IIS) pathway. PFHxS stimulated the fat content in F1 and F4 with similar disturbances on the lipid metabolism and IIS pathway. The trans -generational results showed that the effects of PFBS and PFHxS on the lipid metabolism and IIS pathway were not totally recovered in the offspring of F1 (i.e., T1-T3) and F4 (i.e., T1′-T3′) which were not continuously exposed. PFHxS showed a common pattern to up-regulate daf-7 in both multi- and trans -generational effects. The long-term consequences of the short-chained PFASs substitutes should be concerned and epigenetic regulations should be considered in future mechanism studies. [Display omitted] • PFBS stimulated the fat content not in F1 but in F4 generation. • PFBS disturbed lipid metabolism and IIS pathway differently from F1 to F4. • PFHS stimulated the fat content in F1 and F4 generation. • PFHS had similar disturbances on lipid metabolism and IIS pathway from F1 and F4. • PFHS commonly up-regulated daf-7 in both multi- and trans -generational effects. [ABSTRACT FROM AUTHOR]

Abstract: New nanocomposites were prepared by melt blending poly(l-lactide) (PLLA), poly(ɛ-caprolactone) (PCL), and organically modified montmorillonite (OMMT). The obtained nanocomposites showed enhanced tensile strength, modulus and elongation at break than that of PLLA/PCL blends. The dynamic mechanical analysis showed the increasing mechanical properties with temperature dependence of nanocomposites. Wide-angle X-ray diffraction analysis and transmission electron microscopy indicated that the material formed the nanostructure. Adding OMMT improved the thermal stability and crystalline abilities of nanocomposites. The morphology was investigated by environmental scanning electron microscopy, which showed that increasing content of OMMT reduces the domain size of phase-separated particles. The specific interaction between each polymer and OMMT was characterized by the Flory–Huggins interaction parameter, B, which was determined by the equilibrium melting point depression of nanocomposites. The final values of B showed that PLLA was more compatible with OMMT than PCL. [Copyright &y& Elsevier]

Sulfate radical (SO 4 ·-)-based advanced oxidation processes (AOPs) attract increasing attention in the control of micropollutants. However, SO 4 ·- can react with other chemicals present in water and result in undesired oxidation by-products (OBPs) generation. The formation and degradation mechanisms of CX 3 R-type OBPs during cobalt catalyzed peroxymonosulfate (Co2+/PMS) oxidation were investigated. In the formation of CX 3 R-type OBPs, both Co3+ and SO 4 ·- could convert chloride to free chlorine that then reacted with natural organic matter, leading to the formation of CX 3 R-type OBPs. The concentrations of trichloromethane, chloral hydrate, dichloroacetonitrile, dichloroacetamide and trichloroacetamide after 15 min reaction were 9.8, 3.9, 1.2, 5.9 and 22.3 nM, respectively. Compared to SO 4 ·-, Co3+ played a more significant role in the CX 3 R-type OBP formation and calculated toxicity values of CX 3 R-type OBPs. CX 3 R-type OBPs could not only be formed but also be degraded at the same time during Co2+/PMS oxidation. As for the degradation of CX 3 R-type OBPs, both Co3+ and SO 4 ·- could transform CX 3 R-type OBPs to chloride. Compared to Co3+, SO 4 ·- played a more important role in the degradation of CX 3 R-type OBPs and the conversion from chloride to final by-product chlorate. The adverse effects that results from Co3+ need more attention in SO 4 ·--based AOPs application. ga1 • The formation and degradation pathways of CX 3 R-type OBP were proposed. • Co2+/PMS promotes CX 3 R-type OBP formation compared to PMS. • Co3+ outweighs SO 4 ·- in CX 3 R-type OBP formation. • SO 4 ·- plays a significant role in CX 3 R-type OBP degradation. • Co3+ makes great contributions to toxicity of treated water. [ABSTRACT FROM AUTHOR]

• PFOA showed obesogenic effects in exposed generations and the unexposed offspring. • Fat accumulation was due to greater fatty acid synthesis rather than greater consumption. • PFOA affected pathways including MAPK, fatty acid degradation and TGF-β. • PFOA provoked different results between wild and daf-2 mutant nematodes. • Insulin signal functioned in obesogenic effects and reaction with other pathways. Per-and polyfluoroalkyl substances (PFASs), especially perfluorooctanoic acid (PFOA), have been showed to induce obesogenic effects which may last over generations. However, the underlying mechanisms are not yet clear. In the present study, wild-type N2 Caenorhabditis elegans and the daf-2 mutant were exposed to PFOA for 4 consecutive generations (F0 to F3) at 1.0 ng/L. Effects on fat content and fat metabolism in the directly exposed F0 to F3 generations, the offspring of F0 (T1 to T3) and also those of F3 (T1′ to T3′). Results showed that PFOA significantly stimulated the fat contents in F0 (with the percentage of the control as 184.1%), T1 (189.5%), F1 (167.3%), F2 (238.0%), T2′ (193.9%) and T3′ (159.4%) while inhibited them in T3 (70%). The changes of fat contents over generations were accompanied with significant changes in enzymes facilitating fatty acid synthesis (e.g., acetyl-CoA carboxylase, fatty acid synthase and desaturase, and glycerol phosphate acyltransferase) and those in fatty acid consumption (e.g., acetyl CoA synthetase, fatty acid transport protein, acyl-CoA oxidase and carnitine palmitoyl transferase). Furthermore, RNA-Seq analysis was performed on F0, F3 and T3 generations. Based on the KEGG analysis of differential genes, PFOA exposure affected lipid metabolism signaling pathways including MAPK, fatty acid degradation, TGF-β signaling pathways. Notably, PFOA exposure provoked significantly different effects in daf-2 nematodes on fat contents, lipid metabolizing enzymes and even different signaling pathways. The overall results demonstrated that the obesogenic effects of PFOA were resulted from a complex combination of various enzymes and pathways with essential involvement of insulin signaling pathway. [ABSTRACT FROM AUTHOR]

An anti-wear filler of molybdenum disulfide (MoS 2) coated chopped carbon fiber (SCF) was synthesized by hydrothermal method and blended with nano-SiO 2 to enhance the tribological properties of PEEK composites materials. The results show that the SCF-MoS 2 has stronger adhesion with the PEEK matrix, which is more conducive to the internal stress transfer of PEEK composites. Compared with pure PEEK, the elastic modulus and tensile strength of PEEK/SiO 2 /SCF-MoS 2 composites are increased by 62.04% and 26.49% respectively. The friction coefficient and wear rate of PEEK/SiO 2 /SCF-MoS 2 composites are reduced by 31.43% and 79.18% respectively. In addition, it also shows good tribological properties in the simulation coal mine environment. [ABSTRACT FROM AUTHOR]

The reproductive toxicities over generations are essential to assess the long-term impacts environmental fluoroquinolone antibiotics (FQs). In the present study, the multi-generational effects of ofloxacin (OFL) and norfloxacin (NOR) on reproduction were studied on Caenorhabditis elegans from 9 successive generations (F1-F9). Results showed that OFL showed no effects in F1, stimulation in F2 to F4, and inhibition F5 to F9. The effects of NOR also showed oscillation between stimulation and inhibition across generations. Further biochemical analysis demonstrated that the reproductive toxicities of OFL and NOR were more closely connected with total cholesterol (TCHO), progesterone (P) and testosterone (T), than major sperm protein (MSP) and vitellogenin (Vn). Moreover, OFL and NOR also showed significant trans-generational reproductive toxicities in T4 and T4′, the great-grand-daughter of F1 and F9. Differences between T4 and T4′ and between OFL and NOR, indicated influences of multi-generational exposure and urged more exploration on different mechanisms between FQs. [Display omitted] • Ofloxacin and norfloxacin significantly influenced reproduction of C. elegans. • Effects of OFL and NOR oscillated between stimulation and inhibition from F1 to F9. • Reproductive effects closely related to cholesterol, progesterone and testosterone. • Reproductive toxicities lasted to the non-exposed great-grand-daughter generations. • OFL and NOR showed different multi- and trans-generational effects. [ABSTRACT FROM AUTHOR]

Abstract: The characterization of microbial communities of different depth sediment samples was examined by a culture-independent method and compared with physicochemical parameters, those are organic matter (OM), total nitrogen (TN), total phosphorus (TP), pH and redox potential (Eh). Total genomic DNA was extracted from samples derived from different depths. After they were amplified with the GC-341f/907r primer sets of partial bacterial 16S rRNA genes, the products were separated by denaturing gradient gel electrophoresis (DGGE). The profile of DGGE fingerprints of different depth sediment samples revealed that the community structure remained relatively stable along the entire 45 cm sediment core, however, principal-component analysis of DGGE patterns revealed that at greater sediment depths, successional shifts in community structure were evident. The principle coordinates analysis suggested that the bacterial communities along the sediment core could be separated into two groups, which were located 0–20 cm and 21–45 cm, respectively. The sequencing dominant bands demonstrated that the major phylogenetic groups identified by DGGE belonged to Bacillus, Bacterium, Brevibacillus, Exiguobacterium, γ-Proteobacterium, Acinetobacter sp. and some uncultured or unidentified bacteria. The results indicated the existence of highly diverse bacterial community in the lake sediment core. [Copyright &y& Elsevier]

The microstructure, mechanical property and corrosion behavior of Al/Mg dissimilar friction stir welding (FSW) lap joints with and without Zr interlayer were investigated based on the optimized processing parameters. The macrostructural examination revealed that the processing window for the Al/Mg FSW lap joints was broadened by the Zr interlayer. The microstructural analysis by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS) indicated that the Zr interlayer provided more favorable microstructures and elemental distributions to the Al/Mg joint. The alternating band-like stripes in the weld were obviously refined and the detrimental Al Mg intermetallic compounds (IMCs) between the base materials were suppressed by the Zr interlayer. The microhardness difference on the cross-section of the Al/Mg joint was decreased to show a more uniform stress distribution state for the Al/Zr/Mg joint. The tensile shear failure strength of the Al/Mg joint was increased by 46.9% from 6.4 N/mm2 to 9.4 N/mm2 after the addition of Zr interlayer. The results of electrochemical corrosion and immersion corrosion tests showed that the Al/Mg and Al/Zr/Mg joints presented differentiated corrosion behaviors at representative regions. The weight loss and weight loss rate of the Al/Mg joint in 3.5% NaCl solution was respectively reduced by 18.75% and 19.44% owing to the mitigated corrosion achieved by adding the Zr interlayer. [Display omitted] • Zr interlayer provided favorable microstructures and elemental distributions to joint. • The mechanical property of Al/Mg FSW joint was enhanced by adding Zr interlayer. • The corrosion behavior of Al/Mg FSW joint was improved after Zr interlayer addition. [ABSTRACT FROM AUTHOR]

Simultaneously identifying unknown Young's modulus and boundary conditions of a linear elastic material with the measurements only on a part of its boundary is an inverse problem, which is usually solved by iterative methods in most studies. In this paper, we present a direct inverse method based on the finite element method (FEM) to recover these unknown parameters without iteration. A novel energy-like regularization term is developed to ensure the convergence of the estimated parameters with noisy input. In order to increase the accuracy of estimation, a novel regularization coefficient and its related preprocessing steps are designed based on the Morozov's discrepancy principle to obtain the optimal regularization parameter, which is independent to the observation noise. In numerical experiments, several three-dimensional objects with different shapes and distribution of observed and unknown regions were used to verify the proposed method under different observation noises. Physical experiments were also conducted on a silicone phantom. The results of both numerical and physical experiments successfully recovered the Young's modulus and displacement boundary conditions with expected accuracies close to their corresponding observation noise levels. [Display omitted] • Non-iterative method simultaneously identifies Young's modulus and boundary conditions in three-dimensional domain. • A novel energy-like regularization term to converge the inverse solution with noisy input. • A novel noise-independent regularization coefficient to determine the optimal regularization parameter. • Both numerical experiments and physical phantom experiments verified accuracy of the method. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT)-reinforced hydroxyapatite (HA) composites were successfully fabricated by a double in situ synthesis process, which combined the in situ synthesis of CNTs in HA powders by chemical vapor deposition (CVD) with the further encapsulation of CNTs using HA by a sol–gel method. This double in situ synthesis approach not only improves the homogeneous dispersion of CNTs within the HA matrix, but also enhances the interfacial bonding between the CNTs and HA, thus leading to enhanced mechanical properties. Flexural tests indicated that the flexural strength of the composite is 1.6 times higher than that of pure HA, and significantly higher than that of the commercial and in situ synthesized CNT/HA composites. Furthermore, the in vitro cell culture experiments indicated that the CNT/HA composites fabricated by this double in situ process significantly accelerate the proliferation of fibroblast cells (L-929), compared with those fabricated by traditional methods, confirming their biocompatibility. With this biocompatibility and excellent mechanical properties, the obtained CNT/HA composites have a high potential as biomaterials, particularly in bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Abstract: Water samples were collected from 19 sampling sites along the Huangpu River in June and December 2009. The occurrence, distribution and seasonal variation of 22 antibiotics, including four tetracyclines, three chloramphenicols, two macrolides, six fluoroquinolones, six sulfonamides and trimethoprim were investigated. It was found that all 19 sampling sites were contaminated by antibiotics. Four antibiotics (sulfamerazine, norfloxacin, fleroxacin and sarafloxacin) were not detected. The detection frequencies of the other 18 antibiotics were in the range of 5.3–100%. The median concentrations of the detected antibiotics ranged from quantification limits to 36.71ngL−1 (tetracycline) in June and to 313.44ngL−1 (sulfamethazine) in December. The number of detected antibiotics and the overall antibiotic concentrations were higher in December than in June due to the different river flow conditions. Different dominant antibiotics were observed for each group of antibiotics between June and December. Higher total concentrations of veterinary antibiotics such as tetracyclines were observed in suburban sampling sites than in unban sites, indicating the role of livestock and agricultural activities as an important source of antibiotic contamination. [ABSTRACT FROM AUTHOR]