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Eleven physicochemical parameters of data collected from 12 stations in Daya Bay in 2003 were analyzed by multivariate statistical analysis. Cluster analysis (CA) grouped data from 4 seasons into two groups, the northeast and southwest monsoon periods, representing different natural processes. During the northeast monsoon period, principal component analysis (PCA) and CA group the 12 monitoring sites into Cluster DA1 (S1, S2 and S6) and Cluster DA2 (S3-S5 and S7-S12). During the southwest monsoon period, PCA and CA group the 12 monitoring sites into Cluster WB1 (S1, S2, S7, S9 and S11) and Cluster WB2 (S3-S6, S8, S10, S11 and S12). The spatial heterogeneity within the bay was defined by different hydrodynamic conditions and human activities. These results may be valuable for achieving sustainable use of the coastal ecosystems in Daya Bay. [ABSTRACT FROM AUTHOR]

It is necessary to develop novel and efficient alternatives to fluorocarbon surfactant and prepare fluorine-free environmentally-friendly fire extinguishing agent. The carboxyl modified polyether polysiloxane surfactant (CMPS) with high surface activity was synthesized via the esterification reaction using hydroxyl-containing polyether modified polysiloxane (HPMS) and maleic anhydride (MA) as raw materials. The process conditions of the esterification reaction were optimized by orthogonal tests, and the optimum process parameters were determined as follows: reaction temperature of 85 °C, reaction time of 4.5 h, isopropyl alcohol content of 20% and the molar ratio of HPMS/MA of 1/1. The chemical structure, surface activity, aggregation behavior, foam properties, wetting properties and electron distribution were systematically investigated. It was found that the carboxyl group was successfully grafted into silicone molecule, and the conjugated system was formed, which changed the interaction force between the molecules and would affect the surface activity of the aqueous solution. The CMPS exhibited excellent surface activity and could effectively reduce the water's surface tension to 18.46 mN/m. The CMPS formed spherical aggregates in aqueous solution, and the contact angle value of CMPS is 15.56°, illustrating that CMPS had excellent hydrophilicity and wetting performance. The CMPS can enhance the foam property and has good stability. The electron distribution results indicate that the introduced carboxyl groups are more inclined towards the negative charge band, which would be conducive to weak the interaction between molecules and improve the surface activity of the solution. Consequently, new foam fire extinguishing agents were prepared by using CMPS as a key component and they exhibited excellent fire-fighting performance. The prepared CMPS would be the optimal alternative to fluorocarbon surfactant and could be applied in foam extinguishing agents. [ABSTRACT FROM AUTHOR]

Abstract: Dissolved iron profiles along a north–south transect along 158°W in the tropical Pacific show evidence of two deepwater anomalies. The first extends from Station ALOHA (22.78°N) to the equator at ∼1000–1500m and lies below the maximum apparent oxygen utilization and nutrient (N, P) concentrations. The feature is not supported by vertical export processes, but instead corresponds with the lateral dilution field of δ3He derived from the Loihi seamount, Hawaii, though a sediment source associated with the Hawaiian Island Chain cannot be entirely ruled out. The second, deeper (2000–3000m) anomaly occurs in tropical South Pacific waters (7°S) and also does not correlate with the depths of maximum nutrient concentrations or apparent oxygen utilization, but it does coincide closely with δ3He emanating from the East Pacific Rise, more than 5000km to the east. We hypothesize that these anomalies represent the long-range (>2000km) transport of hydrothermal iron residuals, stabilized against scavenging by complexation with excess organic ligands in the plume source regions. Such trace leakage of hydrothermal iron to distal plume regions would have been difficult to identify in most hydrothermal vent mapping studies because low analytical detection limits were not needed for the proximal plume regions. These findings suggest that hydrothermal activity may represent a major source of dissolved iron throughout the South Pacific deep basin today, as well as other regions having high mid-ocean spreading rates in the geologic past. In particular, we hypothesize that high spreading rates along the South Atlantic and Southern Ocean mid-oceanic ridges, combined with the upwelling ventilation of these distal hydrothermal plumes, may have increased ocean productivity and carbon export in the Southern Ocean. Assessing the magnitude and persistence of dissolved hydrothermal iron in basin scale deep waters will be important for understanding the marine biogeochemistry of iron and, potentially, on ocean productivity and climate change during the geologic past. [Copyright &y& Elsevier]

Abstract: The absence of accurate measurements of lead (Pb) isotopic composition in the North Pacific abyssal water has made it difficult to assess the relative importance of what are believed to be the two major Pb sources: the natural Pb introduced during preindustrial time and recent anthropogenic Pb resulting from leaded gasoline combustion and high temperature industrial activities. Here we report a vertical profile of seawater 206Pb/207Pb ratio and a meridional section of Pb concentration in the North Pacific Ocean. We observe 2–3-fold increases in Pb concentration along the deep-water flow path and a deep-water 206Pb/207Pb ratio (∼1.188) substantially lower than the pre-industrial value (∼1.210). These data suggest that anthropogenic Pb has invaded the North Pacific abyssal water and become the predominant Pb source there. A simple model calculation based on these data indicates that the anthropogenic Pb is transported to the deep ocean by sinking particles and that this Pb vertical flux has a 206Pb/207Pb ratio that decreased during the past two centuries. [Copyright &y& Elsevier]

Abstract: Experiments were conducted using a semi-continuous batch protocol to leach iron from aerosol samples. In this procedure, aerosol samples were leached in an all-Teflon flow-through reaction chamber by multiple (3–4) aliquots (~40 mL) of leaching solution per predetermined leaching period. Several types of aerosols and leaching solutions were tested. The percent iron solubility obtained from aerosols collected in two urban regions was lower (~1%) than the solubility from samples collected in the open ocean (6–13%). This regional variability was greater than the variability obtained when leaching the same aerosols using different leaching solutions. A review of field and laboratory studies from the literature also suggests that different types of aerosols produce more variability in aerosol iron solubility estimates than do different leaching protocols. Colloidal iron was the dominant fraction of aerosol derived dissolved iron in all the experiments carried out during this study, suggesting that the dissolution of aerosol iron in seawater is dominated by the colloidal iron fraction. [Copyright &y& Elsevier]

Abstract: Accuracy of the Scatchard linearization data processing method for competitive ligand exchange (CLE)–cathodic stripping voltammetry (CSV) measurements of seawater Fe-organic complexation in two-ligand case is examined with idealized Fe titrations data sets that are simulated using preset values of ligand parameters (conditional binding constants and total ligand concentrations). The results reveal substantial inherent artifacts for this method. An examination of patterns by which these artifacts vary with changes in Fe-binding strength of natural ligands relative to that of the added ligand suggests that the artifacts result not only from underestimated voltammetric sensitivity, but also from inadequate separation of individual ligand''s contribution to Fe complexation at each titration point. For idealized simulated titration data, these artifacts can be eliminated by a procedure that combines non-linear regression with Turoczy and Sherwood''s iteration. The method is demonstrated by reproducing preset values of ligand parameters over a diverse range of organic ligand alpha coefficients and by modeling titration data determined by CLE–CSV for seawater samples collected from the Eastern Bering Sea. Error analysis suggests that the sensitivity of model-derived ligand parameters to the error in the titration data is a strongly non-linear function of ligand parameters. Accurate measurement of titration data is thus required to use this method for accurate CSV measurements of seawater Fe-organic complexation. [Copyright &y& Elsevier]

[Display omitted] • A system containing Ni–W catalyst and dodecane was used for the HDO of phenolics. • The Ni0 and WO x species derived from NiWO 4 precursors were key to HDO. • 10Ni–15WO x /NiAl 2 O 4 was effective for HDO reaction at 250 °C, 4 MPa, and 4 h. • The formation of cyclohexane was promoted successfully using a dodecane solvent. • Cycloalkanes with a high content of 44.3% were obtained by the HDO of bio-oil. Hydrodeoxygenation (HDO) of lignin-derived bio-oil offers a promising route for the production of advanced biofuels. However, the conventional HDO of lignin-derived bio-oil faces serious problems, such as low hydrocarbon yield and easy deactivation of catalysts. Herein, a novel reaction system consisting of a highly stable bifunctional catalyst (i.e., Ni−WO x /NiAl 2 O 4) and a dodecane solvent was developed for the HDO of lignin-derived phenolics. The Ni0 species, derived from NiWO 4 precursors on the NiAl 2 O 4 , were of small crystallite size and high dispersion, together with the strong oxophilicity of W, thereby exhibiting high activity. The use of a highly stable NiAl 2 O 4 spinel support and the replacement of common solid acid with more stable WO x for the cleavage of C O bond accounted for excellent stability. The optimized 10Ni−15WO x /NiAl 2 O 4 exhibited a high guaiacol conversion of 97.8% with a high cycloalkane yield of 83.8% under the optimum conditions (250 °C, 5 MPa H 2 , and 4 h). Cycloalkanes with a high yield over 90% were also obtained by the HDO of other complex lignin-derived compounds. More importantly, the catalyst always retained its initial activity for the HDO of guaiacol in five runs, with negligible coke formation. Subsequently, the HDO behavior of the bio-oil obtained from walnut shell pyrolysis was also studied. The relative content of cycloalkanes in the products reached 44.3% after the reaction. This study highlights the prospect of a highly stable catalyst consisting of hydrogenation metal and oxophilic promoter, and dodecane solvent to enable efficient production of cycloalkanes from the HDO of lignin-derived phenolics. [ABSTRACT FROM AUTHOR]

Abstract: A low-blank pre-concentration procedure is described for the analysis of picomolar iron (Fe) in seawater by isotope dilution high-resolution inductively coupled plasma mass-spectrometry (HR-ICPMS). The procedure uses a two-step Mg(OH)2 co-precipitation procedure to extract Fe from a 50 ml seawater sample into a 100 μl 4% nitric acid (HNO3) solution followed by HR-ICPMS measurement. The high pre-concentration ratio (∼500:1) achieved by the procedure minimizes the Fe blank due to ICPMS instrumental Fe background and results in a detection limit of ∼2 pM and a precision of ∼4% at the 50 pM Fe level. The measurement of a low-Fe seawater sample spiked with gravimetric Fe standard shows that the method can clearly distinguish 0.01 nM Fe from 0.02 nM Fe in seawater with high accuracy. The method is demonstrated by the analysis of dissolved Fe in the equatorial Pacific Ocean. [Copyright &y& Elsevier]

Presents research findings indicating that previously presumed 'dissolved' iron concentrations in the oligotropic North Atlantic and North Pacific are present in colloidal size range. Depletion of soluble iron and iron-binding organic ligand and enrichment at depth; Maximum levels of colloidal iron at the surface; Results suggesting that dissolved iron may be less available to phytoplankton.

The environmentally friendly fluorine-free fire extinguishing agent based on the silicone surfactant was developed in order to solve the environmental hazards and bio-accumulative of traditional aqueous film-forming foam (AFFF). The carboxyl modified polyether polysiloxane surfactant (CMPS) was an efficient alternative to fluorocarbon surfactant, which was firstly synthesized via the esterification reaction using hydroxyl-containing polyether modified polysiloxane (HPMS) and maleic anhydride (MA) as raw materials. Then the surface activity, foam properties, micellar morphology of the CMPS and four hydrocarbon surfactants, as well as their mixture are evaluated by surface tension, Ross-Miles and cryo-transmission electron microscopy (Cryo-TEM). And the suitable key amount of CMPS and hydrocarbon surfactants added to the extinguishing agent were optimized by orthogonal tests. Moreover, the effect of foam stabilizer on the surface activity, foam property and fire extinguishing performance of fire extinguishing agent are also analyzed. Consequently, a new environmentally friendly fluorine-free fire extinguishing agent was prepared and the surface tension, the interfacial tension, foam properties, bubble morphology, spreading behavior and fire extinguishing mechanism were systematically characterized. The Cryo-TEM results illustrate that the intense interaction among silicone and hydrocarbon molecules exists in the the mixture of CMPS and hydrocarbon surfactants, which is produced through the change of micellar morphology, i.e. microscopic larger spheroidal micelles of CMPS transited to smaller spheroidal micelles and wormlike micelles in the mixed system. The surface tension of synthesized foam extinguishing agent is 22.3 mN/m and the spread coefficient is 0.9 mN/m, which has excellent surface activity and spreading property. The prepared foam extinguishing agent exhibits superior fire-fighting property, which can be attributed to the high surface activity, good foam property and superior foam stability. The research results of this paper lay a theoretical foundation for the research and development of efficient environmentally friendly foam extinguishing agent. [Display omitted] • CMPS was successfully synthesized via esterification reaction. • CMPS surfactant has superior surface activity, foaming ability and foam stability. • The percent of CMPS and hydrocarbon surfactants were optimized by orthogonal tests. • Synergistic effect between CMPS and hydrocarbon improves extinguishing performance. • Foam stabilizer affects the physical-chemical property and extinguishing performance. [ABSTRACT FROM AUTHOR]

Herein, the SrTiO 3 -TiO 2 -CaTiO 3 /Cu 2 O quaternary composite has been designed and prepared via one-step hydrothermal process followed by a NaBH 4 reduction treatment. By comparing the H 2 production rate (HPR) of Sr-Ti-Ca/Cu samples prepared by different Cu sources, it is found that Sr-Ti-Ca/Cu has the best H 2 production performance when CuCl 2 is as Cu source. As expected, the highest HPR of Sr-Ti-Ca/Cu sample is up to 5.088 mmol g−1 h−1, which is 195.7 times as higher as that of the Sr-Ti-Ca sample (0.026 mmol g−1 h−1) under the same conditions. Moreover, the HPR reached 0.692, 0.530 and 0.647 mmol g−1 h−1 in tap water, lake water and river water, indicating that the photocatalyst has high practicability in natural water sources. In addition, the experiment of the tap water composition effect on H 2 production performance shows that NO 3 − and SO 4 2− ions have great negative influence on the HPR. Compared with Sr-Ti-Ca, the light absorption of Sr-Ti-Ca/Cu extends over the entire visible region, the interface resistance decreases, and the photocurrent density increases. These results suggest that the well-designed dual p-n heterojunctions and dual type-II heterojunctions in Sr-Ti-Ca/Cu sample can enhance the light absorption in the ultraviolet region and realize the rapid separation and migration of photogenerated charge, thereby accelerating the production of H 2. This work shows the strong advantage and potential of non-precious metal efficient photocatalyst system for producing H 2 from deionized water and natural fresh water. The SrTiO 3 -TiO 2 -CaTiO 3 /Cu 2 O quaternary composite with dual p-n heterojunctions and dual type-II heterojunctions was successfully designed and prepared by a facile two-step synthesis process firstly, and it exhibited high hydrogen production rate in deionized water and natural fresh water. [Display omitted] • The multi-type heterojunctions can promote the separation of carriers. • Sr-Ti-Ca/Cu exhibited high H 2 production rate. [ABSTRACT FROM AUTHOR]

In order to monitor the state of bushing online, an intelligent monitoring system for transformer bushing was developed. A four‐in‐one sensor integrating hydrogen sensing technology using palladium nickel alloy, pressure sensing technology, wide range temperature sensing, and micro water measurement technology was developed. A three‐in‐one integrated sensor based on micro current detection technology was developed to realize online monitoring of bushing dielectric loss, capacitance, and partial discharge. The test results show the hydrogen measurement range of sensor is 0 to 10,000 μL/L, and the measurement uncertainty is lower than 10% or 10 μL/L. The pressure measurement range is 0 to 1.0 MPa, and the uncertainty is lower than 0.3%. The temperature measurement range is −40°C to 85°C, and the uncertainty is lower than ± 1°C. The micro water measurement range is 0 to 1000 μL/L, and the measurement uncertainty is lower than ± 5% or 10 μL/L. The dielectric loss and capacitance error increased by one order of magnitude compared to current standards. The resolution of partial discharge is 5 pC. The performance of the device fully satisfies the requirements for online monitoring of transformer bushing. It has been installed in dozens of 330 and 750 kV substations, providing a reliable guarantee for safe operation of transformer bushing. [ABSTRACT FROM AUTHOR]

Although structurally similar to type II counterparts, type I or activin receptor-like kinases (ALKs) are set apart by a metastable helix–loop–helix (HLH) element preceding the protein kinase domain that, according to a longstanding paradigm, serves passive albeit critical roles as an inhibitor-to-substrate-binding switch. A single recurrent mutation in the codon of the penultimate residue, directly adjacent the position of a constitutively activating substitution, causes milder activation of ACVR1/ALK2 leading to sporadic heterotopic bone deposition in patients presenting with fibrodysplasia ossificans progressiva, or FOP. To determine the protein structural–functional basis for the gain of function, R206H mutant, Q207D (aspartate-substituted caALK2) and HLH subdomain-truncated (208 Ntrunc) forms were compared to one another and the wild-type enzyme through in vitro kinase and protein–protein interaction analyses that were complemented by signaling read-out (p-Smad) in primary mouse embryonic fibroblasts and Drosophila S2 cells. Contrary to the paradigm, the HLH subdomain actively suppressed the phosphotransferase activity of the enzyme, even in the absence of FKBP12. Unexpectedly, perturbation of the HLH subdomain elevated kinase activity at a distance, i.e., allosterically, at the ATP-binding and polypeptide-interacting active site cleft. Accessibility to polypeptide substrate (BMP Smad C-terminal tails) due to allosterically altered conformations of type I active sites within heterohexameric cytoplasmic signaling complexes—assembled noncanonically by activin-type II receptors extracellularly—is hypothesized to produce a gain of function of the R206H mutant protein responsible for episodic heterotopic ossification in FOP. [ABSTRACT FROM AUTHOR]

• The Ni–Co alloy and oxophilic species co-catalyzed deoxygenation by hydrogenolysis. • A high selectivity of cycloalkanes (98.9%) was obtained in the HDO of guaiacol. • The 5Ni–5Co/NbO x catalyst also showed high stability and applicability. Hydrodeoxygenation (HDO) of lignin-derived bio-oil is a promising route to produce advanced biofuels. However, the removal of oxygen-containing functional groups with high bond strength in bio-oil challenges the development of efficient, stable, and inexpensive catalysts. In this study, a series of bifunctional catalysts were synthesized by coupling Ni–Co alloy with an oxophilic NbO x support, which was used for the HDO of lignin-derived phenolics to produce cycloalkanes. The Ni–Co alloy formed on the bimetallic catalysts during calcination and reduction was verified by TEM, XPS, and H 2 -TPR measurements, which showed excellent hydrogenolysis activity. The composition of the Ni–Co alloy was the most uniform with a Ni/Co molar ratio of 1, and the catalyst achieved the highest catalytic activity. The oxygen vacancies provided by the NbO x support also enhanced the adsorption of phenolics and promoted the removal of oxygen-containing functional groups by forming a specific configuration. The synergistic catalysis of Ni–Co alloy and oxygen vacancies achieved complete conversion of guaiacol with a high cycloalkane selectivity of 98.9 % under optimal conditions (300 °C, 3 MPa H 2 , and 2 h). More importantly, only marginal deactivation occurred on the 5Ni–5Co/NbO x catalyst after 5 cycles and it was also successfully applied to the efficient conversion of other complex lignin-derived phenolics. Therefore, an efficient and economical strategy of coupling the Ni–Co alloy with an oxophilic NbO x support to catalyze the HDO of lignin-derived phenolics to produce cycloalkanes was prospective. [ABSTRACT FROM AUTHOR]

Bitumen upgrading involves the hydroconversion of larger molecules that require catalyst supports with meso- and/or macropores for access to the active sites. In this study, various activation processes were studied to activate delayed petroleum coke, which is a by-product of oil sands bitumen upgrading and an inexpensive source of carbon. The petroleum coke was subjected to steam, chemical (KOH, NaOH) and combined activation methods at 973 K and 1073 K. The produced materials were characterized with nitrogen physisorption at 77 K and scanning electron microscopy. Combined with the yields, the results suggested that the combination of steam with sodium or potassium increased the mesoporosity of the carbon samples possibly by a catalytic gasification mechanism. A mesopore volume of 0.39 cm 3 /g with a yield of 27% was achieved by simultaneously activating with sodium and steam. Washing the material after activation with sodium and before introducing steam produced the same mesoporosity but doubled the yield, confirming that steam alone is not effective at creating porosity. The accessibility of the larger pores was confirmed with the adsorption of asphaltenes from Athabasca extra-heavy crude oil. The capacity for asphaltene adsorption increased with increasing mesopore volume. [ABSTRACT FROM AUTHOR]

The propagation of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) induced by the release of antibiotics poses great threats to ecological safety and human health. In this study, periodate (PI)/FeS 2 /simulated sunlight (SSL) system was employed to remove representative ARB, ARGs and antibiotics in water. 1 × 107 CFU mL–1 of gentamycin-resistant Escherichia coli was effectively disinfected below limit of detection in PI/FeS 2 /SSL system under different water matrix and in real water samples. Sulfadiazine-resistant Pseudomonas and Gram-positive Bacillus subtilis could also be efficiently sterilized. Theoretical calculation showed that (110) facet was the most reactive facet on FeS 2 to activate PI for the generation of reactive species (·OH, ·O 2 –, h + and Fe(IV)=O) to damage cell membrane and intracellular enzyme defense system. Both intracellular and extracellular ARGs could be degraded and the expression levels of multidrug resistance-related genes were downregulated during the disinfection process. Thus, horizontal gene transfer (HGT) of ARB was inhibited. Moreover, PI/FeS 2 /SSL system could disinfect ARB in a continuous flow reactor and in an enlarged reactor under natural sunlight irradiation. PI/FeS 2 /SSL system could also effectively degrade the HGT-promoting antibiotic (ciprofloxacin) via hydroxylation and ring cleavage process. Overall, PI/FeS 2 /SSL exhibited great promise for the elimination of antibiotic resistance from water. [Display omitted] • PI/FeS 2 /simulated sunlight could eliminate antibiotic resistant bacteria and genes. • ·OH,·O 2 –, h + and Fe(IV)=O contributed to the ARB disinfection. • Gene expression of drug resistance and horizontal gene transfer were inhibited. • PI/FeS 2 /sunlight could successively disinfect ARB in a continuous flow reactor. • FeS 2 /PI/natural sunlight system rapidly disinfected ARB. [ABSTRACT FROM AUTHOR]

To explore the vibration response of the GIS busbar enclosure in a strong electric field, the electric force on the busbar enclosure was solved by the voltage in the circuit and the principle of virtual work. The vibration mode was obtained by finite element technology. Accordingly, the vibration response of the busbar enclosure was obtained by vibration analysis in the frequency domain, and the vibration acceleration of the busbar was monitored in the substation. The simulation results showed that the busbar enclosure was subjected to the electric force because of the fundamental voltage and harmonic voltages in the conductor. By coupling the radial electric force and the vibration mode, it was found that the vibration responses of the busbar enclosure at 100 Hz and 2900 Hz were greater than those at other frequencies. The experimental result showed that the frequency with the highest vibration amplitude was the same as that of the simulation result, and the vibration acceleration amplitude in the experiment and simulation at 2900 Hz was basically consistent, which verified the accuracy of the simulation result. The study shows that the GIS enclosure shell will produce vibration at the two times power frequency and high frequency, which provides an explanation for the high-frequency vibration of busbar shell structure in the ultra-high-voltage substation and provides an objective basis for the design of the busbar enclosure in the ultra-high-voltage substation. [ABSTRACT FROM AUTHOR]

By an in situ hot-injection synthetic method, an anode material composed of monodispersed Ni 12 P 5 nanocrystals in situ grown into three dimensional (3D) reduced graphene oxide (rGO) matrix has been manufactured. The process of fabrication includes functionalization of graphene oxide, nucleation, crystallization and ligand removal. Simple operation, relatively mild and scalable reaction conditions as well as three dimensional (3D) interconnected porous rGO as the matrix have been utilized in the process of fabrication. In the assembled nanostructure, the high electrical conductivity and the interconnected porous network of rGO have contributed to the Ni 12 P 5 /rGO nanocomposites with fast channels for lithium-ion transport and electron transfer. Besides, the Ni 12 P 5 nanocrystals have a small size and monodispersed phase, which are able to accommodate the volume expansion during cycling. Therefore, Ni 12 P 5 /rGO nanocomposites present excellent electrochemical lithium-storage performance, including long-life cycling stability, high heat resistance and high rate capability. [Display omitted] • The monodispersed Ni 12 P 5 nanocrystals grown in situ into reduced graphene oxide matrix via hot-injection method. • Ni 12 P 5 /rGO nanocomposites exhibit excellent lituium-storage performance with long cycle life, high thermal stability, and high rate capability. • The design includes the simple operation of the entire preparation process, mild reaction conditions, and a continuous, scalable production process. [ABSTRACT FROM AUTHOR]

The fabrication of high-performance gas-sensitive materials with enhanced moisture resistance is an important research topic. In this work, monodisperse Y-type CoO hierarchical nanostructures with a branch length of about 16 nm have been prepared, and then uniformly dispersed on the surface of reduced oxide graphene (rGO) by hot injection method. The composite exhibited a rapid response to NO 2 at room temperature. The optimal response was about 40–100 ppm NO 2 , the response time was 620 s to 10 ppm NO 2 and the detection limit was 0.01 ppm. It was due to the combination of more NO 2 adsorption active sites of Y-type CoO and faster carrier transfer of rGO. Even at high relative humidity (RH) conditions of 80%, the sensor still retained a high response value of about 90% of that measured at the normal RH (25%). The effective wrapping of stearate ligands inhibited the entrance of water vapor molecules, which could effectively improve the hydrophobic properties of the composite and resulted in enhanced moisture resistance. It may provide a new path for improved NO 2 detection with enhanced moisture resistance at room temperature. [Display omitted] • Y-type CoO/reduced graphene oxide was synthesized with a hot injection method. • The composite sensor exhibited a rapid response to NO 2 at room temperature. • The composite sensor also presented an improved moisture resistance. • The enhanced moisture resistance was due to the wrapping of stearate ligands. [ABSTRACT FROM AUTHOR]

• The structural differences of biomass had significant influence on pyrolysis mechanism. • Cleavage of glycosidic bond and dissociation of O-acetyl group in softwood hemicellulose were prone to occur. • The breakage of α-ether bond of hemicellulose-lignin bonds mainly occurred via Cα-O concerted cleavage. Biomass pyrolysis involves complex structural changes and numerous chemical reactions. At present, most studies on actual biomass pyrolysis focus on the macroscopic thermal degradation process, while the studies on microscopic pyrolysis rules are still very limited. This work provides a new insight into the pyrolysis mechanism of three types of actual biomass, namely hardwood (eucalyptus saligna), softwood (pinus sylvestris) and straw (corn straw), by combining in-situ characterization of the evolution of biomass structures with density functional theory (DFT) calculations of pyrolysis pathways. Firstly, the evolution of various characteristic structures during biomass pyrolysis was monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFT). It was found that the thermal stability of the same functional group in different biomass samples are not exactly the same, and the structural differences in biomass would lead to different pyrolysis behaviors. Then, considering the great structural difference of hemicellulose in different biomass, the key initial pyrolysis reaction paths including the cleavage of glycosidic bonds, the dissociation of side chains and the opening of sugar ring of hemicellulose were studied by DFT calculations. It was found that the cleavage of glycosidic bonds and the dissociation of O-acetyl side chains of glucomannan in softwood hemicellulose are more advantageous than those of xylan in hardwood and straw hemicellulose. In addition, the cleavage mechanism of hemicellulose-lignin bond (LC), a characteristic connection structure between different components of actual biomass, was investigated. The result showed that the cleavage of Cα-O mainly occurred by concerted mechanism for α-ether bond of LC. [ABSTRACT FROM AUTHOR]

Samples for organic copper (Cu)-binding ligand characterization were collected along the 2013 U.S. GEOTRACES Pacific (GP16) cruise transect from Peru to Tahiti. Full depth profiles of Cu speciation were collected across a dynamic range in oceanographic conditions including a highly productive coastal region, an oxygen deficient zone, a high nutrient low chlorophyll (HNLC) region, an oligotrophic region and a hydrothermal vent plume. Surface waters from Peru to Tahiti exhibited elevated dissolved Cu and ligand concentrations near Peru and then decreased in concentration (< 1 nM) offshore toward the oligotrophic waters. There was also an apparent shelf sediment source of strong Cu-binding ligands near the coast of Peru. Throughout most of the transect dissolved Cu and ligand concentrations were lower in the upper waters and increased with depth, with the highest concentrations near the ocean bottom. The hydrothermal vent sampled during the cruise did not seem to be a source for dissolved Cu but there was a slight elevation of Cu-binding ligands at the vent site. Similar vertical patterns in Cu-binding ligands were seen in both the GP16 dataset and the North Atlantic GEOTRACES (GA03) cruise, with notable differences in deep waters of the Pacific. The older water masses of the Pacific were highlighted by higher concentrations of dissolved Cu, Cu-binding ligands, and the free Cu ion (Cu2+) relative to the deep Atlantic. Excess Cu ligands in both GP16 and GA03 point to a possible fraction of Cu accumulating in the deep Pacific that is inert to ligand exchange, suggesting older waters might contain a high fraction of unreactive Cu. • Strong copper-binding ligands detected near the shelf of Peru. • Offshore oligotrophic waters found to have lowest dissolved copper and copper-binding ligand concentrations • Comparison of copper speciation data between the Atlantic (GA03) and Pacific (GP16) U.S. GEOTRACES transects • Evidence for exchange-inert dissolved copper fraction accumulating in older Pacific deep waters [ABSTRACT FROM AUTHOR]

Integrin α4β1 and α4β7 are overexpressed in macrophages and leukocytes and play important roles in mediating cell homing and recruitment to inflammatory tissues. Herein, to enhance the targeting ability of nanotherapeutics for inflammatory bowel disease (IBD) treatment, cyclosporine A-loaded nanoparticles (CsA NPs) were coated with macrophage membranes (MM-CsA NPs) or leukocyte membranes (LM-CsA NPs). In vitro experiments demonstrated that the physicochemical properties of the nanotherapeutics (e.g., size, zeta potential, polymer dispersity index, and drug release profiles) did not obviously change after cell membrane coating. However, integrin α4β1 and α4β7 were expressed in MM-CsA NPs and LM-CsA NPs, respectively, which significantly inhibited normal macrophage phagocytosis and obviously increased uptake by proinflammatory macrophages and endothelial cells. In vivo experiments verified that cell membrane-coated nanotherapeutics have longer retention times in inflammatory intestinal tissues. Importantly, LM-CsA NPs significantly mitigated weight loss, alleviated colon shortening, decreased disease activity indices (DAIs), and promoted colon tissue repair in acute and chronic colitis model mice. Furthermore, LM-CsA NPs significantly decreased the expression of inflammatory factors such as TNF-α and IL-6 and increased the expression of gut barrier-related proteins such as E-cadherin, ZO-1, and occludin protein in colitis mice., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2024 Shan Li et al.)

The gastrointestinal tract (GIT) is an important and complex system by which humans to digest food and absorb nutrients. The GIT is vulnerable to diseases, which may led to discomfort or even death in humans. Therapeutics for GIT disease treatment face multiple biological barriers, which significantly decrease the efficacy of therapeutics. Recognizing the biological barriers and pathophysiological characteristics of GIT may be helpful to design innovative therapeutics. Nanotherapeutics, which have special targeting and controlled therapeutic release profiles, have been widely used for the treatment of GIT diseases. Herein, we provide a comprehensive review of the biological barrier and pathophysiological characteristics of GIT, which may aid in the design of promising nanotherapeutics for GIT disease treatment. Furthermore, several typical diseases of the upper and lower digestive tracts, such as Helicobacter pylori infection and inflammatory bowel disease, were selected to investigate the application of nanotherapeutics for GIT disease treatment.

Background: Racialized and/or ethnocultural minority older adults in supportive living settings may not have access to appropriate services and activities. Most supportive living facilities are mainstream (not specific to one group); however, culturally specific facilities are purpose-built to accommodate older adults from a particular group. Our objective was to describe the perspectives of diverse participants about access to culturally appropriate care, accessible services, and social and recreation activities in culturally specific and mainstream (non-specific) supportive living facilities., Methods: We conducted semi-structured interviews with 21 people (11 staff, 8 family members, 2 residents) from 7 supportive living homes (2 culturally specific and 5 mainstream) in Alberta, Canada. We used a rapid qualitative inquiry approach to structure the data collection and analysis., Results: Staff and family members described challenges in accessing culturally appropriate care in mainstream facilities. Family members expressed guilt and shame when their relative moved to supportive living, and they specifically described long waitlists for beds in culturally specific homes. Once in the facility, language barriers contributed to quality of care issues (e.g., delayed assessments) and challenges accessing recreation and social activities in both mainstream and culturally specific homes. Mainstream facilities often did not have appropriate food options and had limited supports for religious practices. Residents who had better English language proficiency had an easier transition to supportive living., Conclusions: Racialized and/or ethnoculturally diverse residents in mainstream supportive living facilities did not receive culturally appropriate care. Creating standalone facilities for every cultural group is not feasible; therefore, we must improve the care in mainstream facilities, including recruiting more diverse staff and integrating a wider range of recreation and religious services and food options., (© 2024. The Author(s).)

Inflammatory bowel disease (IBD) is a frequently occurring disease that seriously influences the patient's quality of life. To decrease adverse effects and improve efficacy of therapeutics, nanomedicines have been widely used to treat IBD. However, how to thoroughly release payloads under an inflammatory microenvironment and synergistic therapy of IBD need to be further investigated. To address this issue, cyclosporine A (CsA)-loaded, folic acid (FA)-modified, pH and reactive oxygen species (ROS) dual-responsive nanoparticles (FA-CsA NPs) were fabricated using pH/ROS-responsive material as carrier. The prepared FA-CsA NPs had spherical shape and uniform size distribution and could smartly release their payloads under acid and/or ROS microenvironment. In vitro experiments demonstrated that FA-CsA NPs can be effectively internalized by activated macrophages, and the internalized NPs could down-regulate the expression of proinflammatory cytokines compared to free drug or nontargeted NPs. In vivo experiments verified that FA-CsA NPs significantly accumulated at inflammatory colon tissues and the accumulated NPs obviously improved the symptoms of colitis in mice without obvious adverse effects. In conclusion, our results provided a candidate for the targeted treatment of IBD.

Repurposing clinically approved drugs to construct novel nanomedicines is currently a very attractive therapeutic approach. Selective enrichment of anti-inflammatory drugs and reactive oxygen species (ROS) scavenging at the region of inflammation by stimuli-responsive oral nanomedicine is an effective strategy for the treatment of inflammatory bowel disease (IBD). This study reports a novel nanomedicine, which is based on the excellent drug loading and free radical scavenging ability of mesoporous polydopamine nanoparticles (MPDA NPs). By initiating polyacrylic acid（PAA）polymerization on its surface, a "core-shell" structure nano-carrier with pH response is constructed. Then, under alkaline conditions, using the π-π stacking and hydrophobic interaction between the anti-inflammatory drug sulfasalazine (SAP) and MPDA, the nanomedicines (PAA@MPDA-SAP NPs) loaded efficiently (928 μ g mg -1 ) of SAP was successfully formed. Our results reveal that PAA@MPDA-SAP NPs can pass through the upper digestive tract smoothly and finally accumulate in the inflamed colon. Through the synergistic effect of anti-inflammation and antioxidation, it can effectively reduce the expression of pro-inflammatory factors and enhance the intestinal mucosal barrier, and finally significantly alleviate the symptoms of colitis in mice. Furthermore, we confirmed that PAA@MPDA-SAP NPs have good biocompatibility and anti-inflammatory repair ability under inflammation induction through human colonic organoids. In summary, this work provides a theoretical basis for the development of nanomedicines for IBD therapy., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

We demonstrate a high-power 2.0-μm fiber laser system delivering femtosecond pulses with a fundamental repetition rate of >10 GHz, the highest value so far, to the best of our knowledge. The seed is a self-started fundamentally mode-locked Tm-doped fiber laser that has excellent power and spectral stabilities. The laser system can provide an average power of >600 mW, and the use of soliton-effect-based pulse compression allows the achievement of a pulse duration of 163 fs, leading to a compression factor of ∼ 13. It is anticipated that this new high-power femtosecond fiber laser with a 10-GHz-level fundamental repetition rate can serve as a promising light source for various applications, including laser surgery, micromachining, frequency comb spectroscopy, and nonlinear frequency conversion.

A new isotope dilution inductively coupled plasma mass spectrometry (ICPMS) method is developed to determine picomolar concentrations of titanium (Ti) in seawater. The method applies Mg(OH) 2 coprecipitation to concentrate Ti from seawater, and uses a new 49 Ti- 47 Ti isotope dilution to eliminate the need for separating Ti from seawater Ca, resulting in an isobaric interference-free analysis by high-resolution multicollector ICPMS. The method uses a 1.8 mL seawater sample with a detection limit of 1.6 pmol L -1 that is determined mainly by Ti contamination during sample preparation rather than by ICPMS sensitivity, instrumental Ti background, or isobaric interferences. An oceanographically consistent vertical profile of dissolved Ti in the Sargasso Sea near Bermuda is measured with this method.

A sensitive spectrophotometric method for the determination of dissolved titanium (Ti) in seawater is developed. It involves in-line preconcentration and a long path length liquid waveguide capillary cell (LWCC). Nitrilotriacetic acid (NTA) resin is used to preconcentrate Ti from ∼25 mL seawater sample at pH 1.7, and elution is accomplished with 0.8 mol L -1 hydrochloride acid. The eluted Ti solution is buffered to pH 6.0 with 1.0 mol L -1 ammonium acetate and mixed with 1.5 mmol L -1 Tiron solution. The mixture is then injected into LWCC and measured by spectrophotometry at 420 nm. Before the preconcentration step, the sample is treated with 7 mmol L -1 ascorbic acid to reduce Fe(III) to Fe(II), in order to eliminate the Fe interference. The method is not interfered by Fe(III) and Cu(II) present in seawater samples at concentrations 50-fold higher in relation to Ti, and by Cd(II), Pb(II), Cr(VI), Mn(II), Al(III), Zn(II), and Ni(II) at concentrations 100-fold higher in relation to Ti. It is time efficient (7.5 minutes per sample), sensitive (0.10 nmol L -1 detection limit), precise (1.40% measurement RSD at 1.00 nmol L -1 Ti) and is characterized by a linear range of 0.50-5.00 nmol L -1 Ti. The method was applied to analysis of natural water samples collected from the Jiulongjiang Estuary, Fujian, China., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Certification of trace metals in seawater certified reference materials (CRMs) NASS-7 and CASS-6 is described. At the National Research Council Canada (NRC), column separation was performed to remove the seawater matrix prior to the determination of Cd, Cr, Cu, Fe, Pb, Mn, Mo, Ni, U, V, and Zn, whereas As was directly measured in 10-fold diluted seawater samples, and B was directly measured in 200-fold diluted seawater samples. High-resolution inductively coupled plasma mass spectrometry (HR-ICPMS) was used for elemental analyses, with double isotope dilution for the accurate determination of B, Cd, Cr, Cu, Fe, Pb, Mo, Ni, U, and Zn in seawater NASS-7 and CASS-6, and standard addition calibration for As, Co, Mn, and V. In addition, all analytes were measured using standard addition calibration with triple quadrupole (QQQ)-ICPMS to provide a second set of data at NRC. Expert laboratories worldwide were invited to contribute data to the certification of trace metals in NASS-7 and CASS-6. Various analytical methods were employed by participants including column separation, co-precipitation, and simple dilution coupled to ICPMS detection or flow injection analysis coupled to chemiluminescence detection, with use of double isotope dilution calibration, matrix matching external calibration, and standard addition calibration. Results presented in this study show that majority of laboratories have demonstrated their measurement capabilities for the accurate determination of trace metals in seawater. As a result of this comparison, certified/reference values and associated uncertainties were assigned for 14 elements in seawater CRMs NASS-7 and CASS-6, suitable for the validation of methods used for seawater analysis.

The paired-domain transcription factor PAX9 plays a critical role in tooth development, as heterozygous mutations in PAX9 have been shown to be associated with human tooth agenesis. In this study, we report 2 novel missense mutations, gly6arg (G6R) and ser43lys (S43K), in the paired domain of PAX9 in Chinese patients with varying degrees of nonsyndromic tooth agenesis. Excluding third molars, the individual with the G6R mutation was missing 2 mandibular incisors and a maxillary premolar, while the phenotype of individuals with the S43K mutation consisted of peg-shaped upper lateral incisors and missing molars, premolars and canines. As these 2 mutations occur at highly conserved amino acids in the PAX gene family and between different species, we further analyzed the effects of the mutations on the function of the resulting proteins. Immunofluorescence and immunoblotting studies showed that the mutations did not alter nuclear localization in mammalian cells. Gel shift and super shift assays indicate that both mutant proteins bound DNA at a lower level than the normal protein, with G6R having a greater affinity for DNA than S43K. Likewise, the G6R protein was able to transcriptionally activate a Bmp4 promoter construct to a greater extent than S43K. Our finding that the severity of tooth agenesis in the patients was correlated to the DNA-binding capacity of the mutated PAX9 9proteins supports the hypothesis that DNA binding is responsible for the genetic defect., (Copyright 2008 S. Karger AG, Basel.)