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Climate changes significantly impact greenhouse gas emissions from wetland soil. Specifically, wetland soil may be exposed to oxygen (O2) during droughts, or to sulfate (SO42-) as a result of sea level rise. How these stressors - separately and together - impact microbial food webs driving carbon cycling in the wetlands is still not understood. To investigate this, we integrated geochemical analysis, proteogenomics, and stoichiometric modeling to characterize the impact of elevated SO42- and O2 levels on microbial methane (CH4) and carbon dioxide (CO2) emissions. The results uncovered the adaptive responses of this community to changes in SO42- and O2 availability and identified altered microbial guilds and metabolic processes driving CH4 and CO2 emissions. Elevated SO42- reduced CH4 emissions, with hydrogenotrophic methanogenesis more suppressed than acetoclastic. Elevated O2 shifted the greenhouse gas emissions from CH4 to CO2. The metabolic effects of combined SO42- and O2 exposures on CH4 and CO2 emissions were similar to those of O2 exposure alone. The reduction in CH4 emission by increased SO42- and O2 was much greater than the concomitant increase in CO2 emission. Thus, greater SO42- and O2 exposure in wetlands is expected to reduce the aggregate warming effect of CH4 and CO2. Metaproteomics and stoichiometric modeling revealed a unique subnetwork involving carbon metabolism that converts lactate and SO42- to produce acetate, H2S, and CO2 when SO42- is elevated under oxic conditions. This study provides greater quantitative resolution of key metabolic processes necessary for the prediction of CH4 and CO2 emissions from wetlands under future climate scenarios.

Rates of microbial processes are fundamental to understanding the significance of microbial impacts on environmental chemical cycling. However, it is often difficult to quantify rates or to link processes to specific taxa or individual cells, especially in environments where there are few cultured representatives with known physiology. Here, we describe the use of the redox-enzyme-sensitive molecular probe RedoxSensor™ Green to measure rates of anaerobic electron transfer physiology (i.e., sulfate reduction and methanogenesis) in individual cells and link those measurements to genomic sequencing of the same single cells. We used this method to investigate microbial activity in hot, anoxic, low-biomass (~103 cells mL-1) groundwater of the Death Valley Regional Flow System, California. Combining this method with electron donor amendment experiments and metatranscriptomics confirmed that the abundant spore formers including Candidatus Desulforudis audaxviator were actively reducing sulfate in this environment, most likely with acetate and hydrogen as electron donors. Using this approach, we measured environmental sulfate reduction rates at 0.14 to 26.9 fmol cell-1 h-1. Scaled to volume, this equates to a bulk environmental rate of ~103 pmol sulfate L-1 d-1, similar to potential rates determined with radiotracer methods. Despite methane in the system, there was no evidence for active microbial methanogenesis at the time of sampling. Overall, this method is a powerful tool for estimating species-resolved, single-cell rates of anaerobic metabolism in low-biomass environments while simultaneously linking genomes to phenomes at the single-cell level. We reveal active elemental cycling conducted by several species, with a large portion attributable to Ca. Desulforudis audaxviator.

Estuarine wetlands harbor considerable carbon stocks, but rising sea levels could affect their ability to sequester soil carbon as well as their potential to emit methane (CH4). While sulfate loading from seawater intrusion may reduce CH4 production due to the higher energy yield of microbial sulfate reduction, existing studies suggest other factors are likely at play. Our study of 11 wetland complexes spanning a natural salinity and productivity gradient across the San Francisco Bay and Delta found that while CH4 fluxes generally declined with salinity, they were highest in oligohaline wetlands (ca. 3-ppt salinity). Methanogens and methanogenesis genes were weakly correlated with CH4 fluxes but alone did not explain the highest rates observed. Taxonomic and functional gene data suggested that other microbial guilds that influence carbon and nitrogen cycling need to be accounted for to better predict CH4 fluxes at landscape scales. Higher methane production occurring near the freshwater boundary with slight salinization (and sulfate incursion) might result from increased sulfate-reducing fermenter and syntrophic populations, which can produce substrates used by methanogens. Moreover, higher salinities can solubilize ionically bound ammonium abundant in the lower salinity wetland soils examined here, which could inhibit methanotrophs and potentially contribute to greater CH4 fluxes observed in oligohaline sediments.IMPORTANCELow-level salinity intrusion could increase CH4 flux in tidal freshwater wetlands, while higher levels of salinization might instead decrease CH4 fluxes. High CH4 emissions in oligohaline sites are concerning because seawater intrusion will cause tidal freshwater wetlands to become oligohaline. Methanogenesis genes alone did not account for landscape patterns of CH4 fluxes, suggesting mechanisms altering methanogenesis, methanotrophy, nitrogen cycling, and ammonium release, and increasing decomposition and syntrophic bacterial populations could contribute to increases in net CH4 flux at oligohaline salinities. Improved understanding of these influences on net CH4 emissions could improve restoration efforts and accounting of carbon sequestration in estuarine wetlands. More pristine reference sites may have older and more abundant organic matter with higher carbon:nitrogen compared to wetlands impacted by agricultural activity and may present different interactions between salinity and CH4. This distinction might be critical for modeling efforts to scale up biogeochemical process interactions in estuarine wetlands.

[Display omitted] • NO x conversion and N 2 selectivity are significantly enhanced in the presence of SO 2. • The decrease in CO oxidation ability is the main reason for the improvement in NO reduction performance. • L-H reaction pathways for CO oxidation are inhibited by the formation of sulfate species. • The promotional mechanism of SO 2 on CO-SCR reaction over Ir-based catalysts is proposed. Generally, sulfur poisoning is considered to be one of the main factors contributing to the deactivation of selective catalytic reduction of NO x by CO (CO-SCR) catalysts, while the promotional effect of SO 2 on NO reduction over Ir/SiO 2 is observed which is an interesting scientific phenomenon. After the introduction of 20 ppm SO 2 , NO x conversion increased from ∼ 40 % to ∼ 90 % at 275 °C, and N 2 selectivity increased from ∼ 80 % to 100 % at 200 ∼ 300 °C. Furthermore, the promoting effect could remain unchanged after 24 h of continuous reaction. However, the temperature point for achieving complete conversion of CO increased from 225 °C to 275 °C after the introduction of SO 2. Experimental characterization and theoretical calculation jointly proved that the inhibition of CO oxidation by the generation of sulfate was the main reason for promoting NO reduction. Under the coexistence of O 2 and SO 2 , SO 2 was firstly oxidized to SO 3 on the iridium surface and generated sulfate species on surface hydroxyl groups of SiO 2. Some active sites for O 2 adsorption were covered by the generated surface sulfate, and adsorbed CO was hard to react with adsorbed O 2 , resulting in Langmuir–Hinshelwood (L-H) reaction pathways for CO oxidation being inhibited. Therefore, unoxidized CO reacted with NO adsorbed species and generated N 2 O to generate N 2 and CO 2 , improving NO reduction. This new insight has implications for understanding the promotional effect of SO 2 on NO reduction with CO in the presence of O 2. [ABSTRACT FROM AUTHOR]

The parasitic nematode Heligmosomoides polygyrus bakeri secretes the HpARI family, which bind to IL-33, either suppressing (HpARI1 and HpARI2) or enhancing (HpARI3) responses to the cytokine. We previously showed that HpARI2 also bound to DNA via its first complement control protein (CCP1) domain. Here, we find that HpARI1 can also bind DNA, while HpARI3 cannot. Through the production of HpARI2/HpARI3 CCP1 domain-swapped chimeras, DNA-binding ability can be transferred, and correlates with in vivo half-life of administered proteins. We found that HpARI1 and HpARI2 (but not HpARI3) also binds to the extracellular matrix component heparan sulphate (HS), and structural modelling showed a basic charged patch in the CCP1 domain of HpARI1 and HpARI2 (but not HpARI3) which could facilitate these interactions. Finally, a mutant of HpARI2 was produced which lacked DNA and HS binding, and was also shown to have a short half-life in vivo. Therefore, we propose that during infection the suppressive HpARI1 and HpARI2 proteins have long-lasting effects at the site of deposition due to DNA and/or extracellular matrix interactions, while HpARI3 has a shorter half-life due to a lack of these interactions. [ABSTRACT FROM AUTHOR]

In this paper, the effect of zero-valent iron (Fe0) activated persulfate (PDS) on the removal of enrofloxacin (ENR) was investigated, and the effect and mechanism were analyzed by exploring the effects of Fe0 concentration, PDS concentration, pH, and the influence of anion and aqueous matrix on the removal of ENR by the Fe0/PDS system. The results showed that when [ENR] = 20 µmol/L, [Fe0] = 0.15 g/L, [PDS] = 0.4 mmol/L, the removal rate of ENR was 85.3% at 90 min, the mainradicals were HO•, SO4•− and O2•−. At the same time, the system had a good mineralization effect (TOC removal rate > 40%), in addition, the system did not show obvious toxicity to soil microorganisms after the reaction, furthermore the Fe0/PDS system had a good removal effect on ENR in a wide pH range (4 ≤ pH ≤ 10). There is basically no difference in the removal rate of Fe0/PDS system in ultrapure water and river water. The results of this experiment could provide a reference for the removal of antibiotics based on advanced oxidation techniques based on SO4•−. [ABSTRACT FROM AUTHOR]

Solfataric alteration at the South Sulfur Bank of the former Kilauea caldera produced opal, Mg- and Fe-rich smectites, gypsum, and jarosite through silica replacement of pyroclastic Keanakako'i ash and leaching of basaltic lavas. This site on the island of Hawaii serves as an analog for formation of several minerals found in altered deposits on Mars. Two distinct alteration environments were characterized in this study, including a light-toned, high-silica, friable outcrop adjacent to the vents and a bedded outcrop containing alternating orange/tan layers composed of smectite, gypsum, jarosite, hydrated silica, and poorly crystalline ferric oxide phases. This banded unit likely represents the deposition of pyroclastic material with variations in chemistry over time that was subsequently altered via moderate hydrothermal and pedogenic processes and leaching of basaltic caprock to enhance the Si, Al, Mg, Fe, and Ca in the altered layers. In the light-toned, friable materials closest to the vents along the base of the outcrop, glassy fragments were extensively altered to opal-A plus anatase. Lab measurements of samples returned from the field were conducted to replicate recent instruments at Mars and provide further characterization of the samples. These include elemental analyses, sample texture, XRD, SEM, VNIR/mid-IR reflectance spectroscopy, TIR emittance spectroscopy, and Mössbauer spectroscopy. Variations in the chemistry and mineralogy of these samples are consistent with alteration through hydrothermal processes as well as brines that may have formed through rain interacting with sulfuric fumes. Silica is present in all altered samples, and the friable pyroclastic ash material with the strongest alteration contains up to 80 wt% SiO2. Sulfate mineralization occurred at the South Sulfur Bank through fumarolic action from vents and likely included solfataric alteration from sulfuric gases and steam, as well as oxidation of sulfides in the basaltic caprock. Gypsum and jarosite are typically present in different layers of the altered wall, likely because they require different cations and pH regimes. The presence of both jarosite and gypsum in some samples implies high-sulfate concentrations and the availability of both Ca2+ and Fe3+ cations in a brine percolating through the altered ash. Pedogenic conditions are more consistent with the observed Mg-smectites and gypsum in the tan layers, while jarosite and nontronite likely formed under more acidic conditions in the darker orange layers. Assemblages of smectite, Ca-sulfates, and jarosite similar to the banded orange/tan unit in our study are observed on Mars at Gale crater, Noctis Labyrinthus, and Mawrth Vallis, while high-silica outcrops have been identified in parts of Gusev crater, Gale crater, and Nili Patera on Mars. [ABSTRACT FROM AUTHOR]

The composition of solid solutions in the KNd(SO4)2·H2O–SrSO4·0.5H2O system, synthesized from aqueous solutions of KCl, NdCl3, SrCl2, and H2SO4, was studied by X-ray fluorescence spectrometry. Coefficients of calibration dependences for intensity vs. element concentrations were calculated for Nd, Sr, and K by the least-squares technique. A linear approximation function was used in determining potassium and a parabolic approximation function was recommended in determining neodymium and strontium. The obtained dependences are characterized by low (<1%) relative approximation errors. In the analytical ranges (wt %) for K 0.863−8.892, Sr 8.41−38.03, and Nd 5.296−29.30, the standard deviations were 0.012−0.028, 0.008−0.098, and 0.05−0.27 respectively. [ABSTRACT FROM AUTHOR]

The Mars 2020 Perseverance rover discovered fine‐grained clastic sedimentary rocks in the "Hogwallow Flats" member of the "Shenandoah" formation at Jezero crater, Mars. The Hogwallow Flats member shows evidence of multiple phases of diagenesis including Fe/Mg‐sulfate‐rich (20–30 wt. %) outcrop transitioning downward into red‐purple‐gray mottled outcrop, Fe/Mg clay minerals and oxides, putative concretions, occasional Ca sulfate‐filled fractures, and variable redox state over small (cm) spatial scales. This work uses Mastcam‐Z and SuperCam instrument data to characterize and interpret the sedimentary facies, mineralogy and diagenetic features of the Hogwallow Flats member. The lateral continuity of bedrock similar in tone and morphology to Hogwallow Flats that occurs over several km within the western Jezero sedimentary fan suggests widespread deposition in a lacustrine or alluvial floodplain setting. Following deposition, sediments interacted with multiple fluids of variable redox state and salinity under habitable conditions. Three drilled sample cores were collected from this interval of the Shenandoah formation as part of the Mars Sample Return campaign. These samples have very high potential to preserve organic compounds and biosignatures. Drill cores may partially include dark‐toned mottled outcrop that lies directly below light‐toned, sulfate‐cemented outcrop. This facies may represent some of the least oxidized material observed at this interval of the Shenandoah formation. This work reconstructs the diagenetic history of the Hogwallow Flats member and discusses implications for biosignature preservation in rock samples for possible return to Earth. Plain Language Summary: The Mars 2020 Perseverance rover discovered sedimentary rocks in Jezero crater during the second year of its mission. Some of these rocks were informally named the "Hogwallow Flats" member of the "Shenandoah" formation. These rocks contain abundant clay minerals and sulfates, indicating ancient interactions with liquid water. They may preserve organic matter and signs of life that could tell us whether life was ever present in Jezero crater billions of years ago. The sediments here appear to have undergone physical and chemical changes after deposition—called diagenesis—when interacting with liquid water. These changes, which may have occurred in a lake or a shallow river plain and later when the sediments were shallowly buried, are often associated with favorable conditions for preserving signs of ancient life. However, these changes may also have resulted in the breakdown of these signs of life. This work reconstructs the geologic history of the Hogwallow Flats member and discusses the importance of these rocks for the search for ancient life on Mars. A total of three rock cores were collected by Perseverance from these rocks for return to Earth. These samples have very high potential to preserve organic matter and signs of ancient life. Key Points: Fine‐grained clastic sedimentary rocks at the Hogwallow Flats member underwent limited diagenesisDiagenesis may have occurred in a lake or a shallow river plain and later when the sediments were shallowly buriedMottling features, sulfates and clay minerals within drilled rock core samples for Mars Sample Return have high astrobiological potential [ABSTRACT FROM AUTHOR]

The compounds K2Zr(SO4)3·2.5H2O, K2Zr(SeO4)3, and K2Zr2O(SeO4)4 were synthesized at 200 °C by reaction of Zr2O2(CO3)(OH)2 and KHCO3 with the respective acids H2SeO4/H2SO4 and minor H2O. Zr(OH)2(SeO4)·H2O originates from an analogous experiment at 215 °C without KHCO3. All four phases form colorless crystals up to several tenths of a mm and were investigated by single crystal X-ray diffraction. K2Zr(SO4)3·2.5H2O is monoclinic, space group P21/c (No. 14), with a = 7.295(2) Å, b = 13.925(3) Å, c = 12.579(3) Å, β = 95.32(3)°, V = 1272.3(4) Å3, Z = 4, R1 = 0.025. K2Zr(SeO4)3 and K2Zr2O(SeO4)4 are both triclinic, space group P 1 ¯ (No. 2), with a = 7.570(1) Å, b = 10.500(1) Å, c = 14.400(1) Å, α = 85.55(1)°, β = 88.04(1)°, γ = 87.82(1)°, V = 1139.7(2) Å3, Z = 4, R1 = 0.049, and a = 5.400(1) Å, b = 7.328(1) Å, c = 9.642(1) Å, α = 95.81(1)°, β = 95.20(1)°, γ = 94.27(1)°, V = 376.74(4) Å3, Z = 1, R1 = 0.020, respectively. Zr(OH)2(SeO4)·H2O crystallizes in the monoclinic space group C2/c (No. 15), with a = 6.684(1) Å, b = 12.998(2) Å, c = 6.792(1) Å, β = 97.37(1)°, V = 585.14(6) Å3, Z = 2, R1 = 0.013. [ABSTRACT FROM AUTHOR]

Transition metal sulfides (TMS) exhibit significant promise as non‐noble‐metal electrocatalysts for the oxygen evolution reaction (OER) in alkaline environments, notwithstanding their susceptibility to long‐term instability due to the gradual leaching of surface‐reconstructed sulfate ions (SO42−). In this study, a sulfate ion‐assisted strategy is proposed to stabilize the surface‐reconstructed SO42− of FeNiS2. The findings reveal that SO42− experiences considerable loss in KOH due to the infinite concentration gradient of SO42− on the surface. Conversely, in K2SO4/KOH, this strategy mitigates rapid leaching and preserves the predominant surface‐reconstructed SO42−, thereby enhancing stability in both accelerated degradation (5000 cycles) and long‐term (≥120 h) tests, with ≈95% current density retained. Furthermore, the optimal concentration of SO42− proves to be crucial, as supported by both experimental and theoretical results. This approach offers insights into bolstering the long‐term OER stability of TMS and similar compounds, thereby advancing the prospects for widespread application in electrocatalytic water splitting. [ABSTRACT FROM AUTHOR]

Sulfate dry-wet cycle erosion significantly affects the mechanical properties of concrete. Investigating the uniaxial compressive stress-strain relationship under these conditions is essential for developing accurate constitutive models. This study analyzes the uniaxial stress-strain curves of concrete subjected to dry-wet cycles in 5% and 15% sulfate solutions. The results show that the initial compaction phase in the stress-strain relationship is particularly pronounced under increasing sulfate concentrations and cycle counts. The concrete experiences an extended compaction phase, which accounts for up to 35.71% of the total strain process. This finding challenge traditional constitutive models, which struggle to accurately describe this phase. To address this issue, the study develops a nonlinear stress-strain model for concrete, incorporating the initial damage caused by sulfate dry-wet cycle erosion, based on Weibull statistical damage mechanics principles. The research indicates that the effects of sulfate concentration and cycle count are predominantly reflected in the pronounced nonlinearity of the skeleton strain function's opening size (a) and shape characteristics (b), modeled using a fourth-degree polynomial. The model demonstrates an excellent fit to experimental data with an R2 value of 0.99989, showing that the proposed nonlinear stress-strain relationship effectively captures the uniaxial mechanical behavior of concrete under sulfate dry-wet cycle erosion and provides a robust framework for developing constitutive models in such environments. [ABSTRACT FROM AUTHOR]

Fe‐based sulfate materials have attracted much attention in the cathode of sodium‐ion batteries (SIBs) due to their low cost and high operating voltage, as well as possessing application prospects comparable to hard carbon in the anode based on Fe0/Fe2+/Fe3+ redox properties. However, the poor conductivity and the tendency to agglomerate have limited their further application. Herein, the study constructs a dual‐conductive structure that the Na2.31Fe1.72(SO4)3 particles with amorphous carbon in situ‐coated embedded in ketjen black (KB) conducting carbon networks (NFS/KB) via a solid phase ball‐milling strategy, which effectively enhanced inherent conductivity and electron transfer efficiency among particles of the Fe‐based sulphate. The NFS/KB can provide a reversible capacity of 92 mAh g−1 at 0.1 C and stable cycling stability at high current (85% retention after 500 cycles at 20 C) as cathode of SIBs. Surprisingly, as anode of SIBs, the NFS/KB delivers a rate performance (149 mAh g−1 at 10 C) that is superior to that of hard carbon. Notably, further application of the material to symmetric SIBs also achieves favorable results. This work effectively enhances the performance of Fe‐based sulphate materials in SIBs with a low‐cost carbon modification method, providing a new approach for the low‐cost symmetric SIBs. [ABSTRACT FROM AUTHOR]

Alloys of Ni–25Cr–(2Mn–1Si) under mixed deposits of ash + (0, 10, 50 and 90) wt% sulphate were exposed to an Ar–60CO2–20H2O gas at 650 and 750 °C for up to 300 h, forming both protective chromia and regions of Ni-rich oxide. The presence of ash + sulphate mixtures improved Ni–25Cr alloy protection, increasing surface coverage by thin, protective chromia compared with the deposit-free condition. Increasing sulphate proportions in these mixtures led to an accelerated chromia scale growth and reduced internal oxidation zone (IOZ). These beneficial effects were more significant at 750 °C, where surface coverage by the protective scale was increased, and a chromia band was formed beneath nonprotective regions at the IOZ-substrate interface. Alloy additions of Mn and Si generally slowed the growth of outer NiO and IOZ but did not lead to exclusive chromia scale formation. [ABSTRACT FROM AUTHOR]

Background: Cancer has been regarded as the most dreaded disease for both human and animals because of its incurability. Canine mammary tumours are common and major problem encountered by academicians and practicing veterinarians. As a result, the current study was conducted to examine the effectiveness and overall impact of different surgico-chemotherapeutic approaches in treating malignant mammary tumors in dogs. Methods: The investigation involved 18 clinical instances of mammary tumors in different breeds, regardless of age or sex and were divided into three groups of six animals each. In Group S, only surgical excision of tumour was performed while animals of Group SD and Group SV were treated with surgical excision followed by administration of Doxorubicin (30 mg/m2) BSA and Vincristine sulphate (0.025 mg/kg) intravenously alongwith DNS at 7th and 14th post-operative days respectively. Different physiological and haemato-bichemical parameters i.e. Hb, PCV, TLC, TPC, DLC, Serum glucose, TSP, SUN, SC, ALT, AST and ALP were recorded preoperatively, postoperatively and following chemotherapy at 10th, 30th and 60th day intervals. Result: The present study showed transient change in the physiological, haematological and biochemical profiles following surgery and chemotherapy treatment. The histopathological analysis showed more cases of adenocarinoma which were followed by mixed carcinoma. Surgery combined with chemotherapy (doxorubicin and vincristine) resulted in minimal to no reoccurrence with few adverse reactions including inappetance, vomition, anaemia and alopecia. It was concluded that the most effective treatment for malignant mammary tumors in dogs is surgical excision followed by sequential vincristine therapy, which efficiently regresses the tumor without causing relapse. [ABSTRACT FROM AUTHOR]

Salbutamol sulphate is an antiasthamatic and bronchodilator agent, with half life of 1.6 hours and requires multiple daily doses to maintain adequate plasma concentrations. The objective of this present study is to develop a sustained release tablet of salbutamol sulphate which releases the drug in a sustained manner over a period, by using different polymers. The drug was formulated and evaluated as per standard procedure and it was found that F6 formulation gives optimum results. [ABSTRACT FROM AUTHOR]

For concrete structures in marine or groundwater environments, sulfate attack is a major factor contributing to the degradation of concrete performance. This paper analyzes the existing literature on the chemical reactions and physical crystallization effects of sulfate attack on cement-based materials, summarizing the degradation mechanisms of corroded concrete. Experiments have been conducted to study the performance evolution of concrete under sulfate attack, considering both external environmental factors and internal factors of the cement-based materials. External environmental factors, such as the temperature, humidity, concentration, and type of sulfate solutions, wet-dry cycles, freeze-thaw cycles, chloride coupling effects, and stray currents significantly impact sulfate attack on concrete. Internal factors, including internal sources of corrosion, the chemical composition of the cement, water-cement ratio, and the content of C-S-H gel and Ca(OH)2, influence the density and sulfate resistance of the cement-based materials. Additionally, five typical methods for enhancing the sulfate resistance of concrete are summarized. Finally, the paper identifies current challenges in the study of corroded concrete and proposes directions for future research. [ABSTRACT FROM AUTHOR]

In order to promote the large-scale utilization of coal gangue in coal mine areas under high sulfate environment, this article prepared shotcrete with different coal gangue substitution rates, and studied the influence law of coal gangue on the sulfate attack resistance of shotcrete under the action of dry-wet cycles. The appearance, mass loss rate, relative dynamic elastic modulus, relative compressive strength, sulfate ion distribution evolution and micromorphology changes before and after erosion were studied, and the influence mechanism of coal gangue on the sulfate attack resistance of shotcrete was obtained. The results show that under the action of sulfate dry-wet cycles, the deterioration process of coal gangue shotcrete (CGS) is divided into three stages: strengthening stage, initial damage and macroscopic damage. The deterioration degree of CGS is synergistically affected by the number of dry-wet cycles and the substitution rate of coal gangue. The sulfate resistance of CGS increases at a substitution rate of 25% (mass fraction). When the substitution rate exceeds 25%, the sulfate attack resistance of CGS decreases with the increase of substitution rate. The research results provide important theoretical support for the application of CGS structures in mines. [ABSTRACT FROM AUTHOR]

Terra Sirenum, a region of Noachian highlands southwest of the Tharsis volcanic complex, is unique in the number, proximity, and diversity of orbital detections of secondary minerals, as the sole region found to date hosting large‐scale deposits of all of Mars' major salts (chlorides, sulfates, carbonates) as well as diverse hydrated silicates. We combine mineralogical information, high‐resolution imagery, and elevation models to investigate the geologic context of these secondary minerals to understand the sources of water and ions for each type of deposit and their spatial/temporal relationships. Carbonates, where present, are part of Noachian basement rocks exposed through cratering and do not appear associated with evaporative sequences. Numerous small detections of the acid sulfate minerals alunite and jarosite mirror the dominant clay cation in the localities they are found—Al phyllosilicates and Fe phyllosilicates, respectively—suggesting in situ formation. We interpret a previously discovered kaolinite‐rich unit overlying Fe/Mg clays across northeast Terra Sirenum as remnants of a widespread ash unit rather than a pedogenic weathering sequence. Sulfate and chloride detections are decoupled, with sulfates in topographic lows likely precipitated from volcanism‐associated groundwaters, while chloride detections are consistent with surface water runoff, in some instances clearly post‐dating volcanic units capping sulfate detections. Volcanic resurfacing of craters in the region is progressively younger from west to east, and crater statistics‐based ages indicate localized sulfate‐ and chloride‐forming processes continue to occur from ∼3.5 to ∼1.4 Ga. We hypothesize that their decoupling points to disconnected, episodic surface and groundwater reservoirs, perhaps separated by a permafrost layer. Plain Language Summary: A major question is how Mars evolved from a water‐rich planet to a dry planet. We study a region southwest of Mars' largest volcanoes with multiple types of water‐related minerals. We use their detections to infer the properties of the water that deposited them and imagery to understand if/how the minerals are related to each other. Chlorides (e.g., table salt) are found in ponds and channels over a wide elevation range. Sulfates are present only in deep basins with signs of volcanic activity. On Earth, sulfates and chlorides are often together, forming during evaporation of a body of water; however, on Mars, the occurrences seem to be separated, which suggests different water sources and that groundwater with sulfur added from volcanic gases was involved in sulfate formation. The deposits both get progressively younger, as young as ∼2 billion years ago, toward the large volcanic region. Furthermore, aluminum clays on top of iron/magnesium clays in this area have been previously interpreted as weathering sequences, which implies a large volume of water. Instead, we find most aluminum clays are part of a volcanic ash layer deposited on top of older iron/magnesium clays, which needs a smaller amount of water to create the observed layering. Key Points: Thick, layered deposits with Al clays in upper strata thin with distance from Arsia Mons, suggesting volcanic ash parent lithologiesChlorides are decoupled from sulfates in deep basins; sulfates likely precipitated from upwelling groundwater with magmatic volatilesAssociated volcanic units have ages pointing to episodic volcanic springs and surface melt waters into the early Amazonian [ABSTRACT FROM AUTHOR]

This study evaluates the impact of the addition of nanoparticles of anodic manganese dioxide (NAMD) on the mechanical properties and resistance to chemical attack of concrete. The research focused on nine concrete mixtures with water/cement ratios of 0.40, 0.45, and 0.50 and NAMD contents of 0, 5, and 10%. The properties of NAMD were analyzed, and fresh concrete properties such as temperature, unit weight, and consistency were measured. The compressive strength was determined at different ages (7, 14, 28, 56, and 90 days). The tensile and flexural strength were evaluated at 28 days, and the longitudinal change generated by the SO4Mg attack was monitored until 90 days. In addition, an accelerated carbonation test was performed on concrete samples with 28 days of curing exposed to an atmosphere of 6% CO2 for one week. The addition of NAMD did not significantly affect the temperature or unit weight of the fresh concrete, but it did influence the consistency. An increase in compressive, tensile, and flexural strength was observed, especially at early ages and for low w/c ratios. The addition of NAMD reduced the expansion of concrete exposed to magnesium sulfate, with 5% being the most effective dose, and reduced the carbonation rate of concrete by up to 40% in mixes with w/c ratios of 0.40 and 0.50. It was shown that the addition of 5% as an effective dose of NAMD improves the mechanical and durability properties of concrete, especially in mixtures with a low water/cement ratio, contributing to the improvement of the quality and strength of concrete. [ABSTRACT FROM AUTHOR]

In connection with our interest in the phytochemical investigation of Elaeocarpus hainanensis Oliv. (Elaeocarpaceae) growing in Vietnam, two new sulphated oleanane triterpenes were obtained herein and structurally identified. Based on the combination of the extensive 1D-, 2D NMR and HR ESI MS spectroscopic data analysis, their chemical structures have been elucidated as 1α,3β-dihydroxy-olean-18-ene 1-sulphate (1) and 1α,3β-dihydroxy-olean-12-ene 1-sulphate (2). Notably, compounds 1 and 2 are corroborating the proposition that triterpenoid sulphates serve as chemosystematic markers of the Elaeocarpus genus. Additionally, all these two new compounds 1 and 2 strongly inhibited α-glucosidase in vitro with the respective IC50 values of 3.81 ± 0.33 µM and 21.27 ± 0.48 µM, which were significantly better than that obtained from positive control, acarbose (IC50 247.73 ± 11.85 µM). [ABSTRACT FROM AUTHOR]

Subsurface treatment systems, such as constructed wetlands, riverbank filtration systems, and managed aquifer recharge systems, offer a low-cost means of removing trace organic contaminants from treated municipal wastewater. To assess the processes through which trace organic contaminants are removed in subsurface treatment systems, pharmaceuticals and several major metabolites were measured in porewater, sediment, and plants within a horizontal levee (i.e., a subsurface flow wetland that receives treated municipal wastewater). Concentrations of trace organic contaminants in each wetland compartment rapidly declined along the flow path. Mass balance calculations, analysis of transformation products, microcosm experiments, and one-dimensional transport modeling demonstrated that more than 60% of the contaminant removal could be attributed to transformation. Monitoring of the system with and without nitrate in the wetland inflow indicated that relatively biodegradable trace organic contaminants, such as acyclovir and metoprolol, were rapidly transformed under both operating conditions. Trace organic contaminants that are normally persistent in biological treatment systems (e.g., sulfamethoxazole and carbamazepine) were removed only when Fe(III)- and sulfate-reducing conditions were observed. Minor structural modifications to trace organic contaminants (e.g., hydroxylation) altered the pathways and extents of trace organic contaminant transformation under different redox conditions. These findings indicate that subsurface treatment systems can be designed to remove both labile and persistent trace organic contaminants via transformation if they are designed and operated in a manner that results in sulfate-and Fe(III)-reducing conditions.

• Oxidative dissolution pathway of stibnite was studied by sulfate oxygen and sulfur isotope compositions. • The relative percentage of water-derived oxygen incorporation into sulfate increase from 5 % to 52 % with longer reaction duration. • A conceptual model of stibnite oxidative dissolution pathway under the aerobic abiotic conditions was proposed. The environmental threat posed by stibnite is an important geoenvironmental issue of current concern. To better understand stibnite oxidation pathways, aerobic abiotic batch experiments were conducted in aqueous solution with varying δ18O H2O value at initial neutral pH for different lengths of time (15-300 days). The sulfate oxygen and sulfur isotope compositions as well as concentrations of sulfur and antimony species were determined. The sulfur isotope fractionation factor (Δ34S SO4-stibnite) values decreased from 0.8‰ to -2.1‰ during the first 90 days, and increased to 2.6‰ at the 180 days, indicating the dominated intermediate sulfur species such as S 2 O 3 2−, S0, and H 2 S (g) involved in Sb 2 S 3 oxidation processes. The incorporation of O into sulfate derived from O 2 (∼100%) indicated that the dissociated O 2 was only directly adsorbed on the stibnite-S sites in the initial stage (0-90 days). The proportion of O incorporation into sulfate from water (27%-52%) increased in the late stage (90-300 days), which suggested the oxidation mechanism changed to hydroxyl attack on stibnite-S sites promoted by nearby adsorbed O 2 on stibnite-Sb sites. The exchange of oxygen between sulfite and water may also contributed to the increase of water derived O into SO 4 2−. The new insight of stibnite oxidation pathway contributes to the understanding of sulfide oxidation mechanism and helps to interpret field data. [ABSTRACT FROM AUTHOR]

Age-related changes affect the ratio between two steroid hormones of the hypothalamic-pituitary-adrenal axis, cortisol and dehydroepiandrosterone (sulfate) (DHEA[S]). Physical activity (PA) may buffer the effects of chronic stress and counteract the aging decline of DHEA(S). Therefore, a systematic review was conducted to understand how PA influences physiological markers of cortisol and/or DHEA(S) and whether there is a difference in observational associations or experimental effects in older adults aged 65 years and older. A narrative synthesis was performed on nine observational studies, and meta-analyses were performed on 22 randomized controlled trials. There was low- to moderate-quality evidence that regular PA beneficially reduces cortisol and increases DHEA(S) levels. Subgroup analyses showed no clinically important differences between men and women, different exercise modalities, or health states. The findings cautiously suggest that regular PA of older adults' own choice that they find enjoyable could be recommended to improve cortisol and/or DHEA(S) levels. [ABSTRACT FROM AUTHOR]

The article describes an X-ray fluorescence method for quantitative analysis of sulfate and total sulfur in bottom sediments of watercourses and reservoirs located in the area of industrial enterprises impact. The quantitative determination of sulfur forms was carried out by analyzing the characteristic curves SKα1,2 and SKβ1,3, as well as the satellite line SKβ′ on X-ray emission spectra measured by an X-ray fluorescence spectrometer with wavelength dispersion. The study shows that these characteristic curves allow not only to determine the predominant form of sulfur, but also to separately conduct quantitative analyses of sulfates and total sulfur after fitting peaks and to separately analyze overlapping spectral lines. The results of quantitative analysis of the chemical state of sulfur by the proposed X-ray fluorescence method were compared with the results of inductively coupled plasma atomic emission spectroscopy and elemental analysis, as well as certified standard samples of soils and sediments. The results are in good agreement with each other.

Serum from 88 pregnant sows and gilts was sampled 24 and 28 days after their first insemination or mating day. The oestrone sulphate (E1S) concentration in the samples was assessed with a commercially available radioimmunoassay kit modified for use with swine serum. The first aim was to test whether it was possible to predict litters of total number <10 piglets at term. The second aim was to compare the use of day 24 or day 28 samples, or of both, in this prediction. Day 24 E1S levels were positively correlated with litter size at term (R2 = 0.26; p < 0.001). E1S levels on day 28 were correlated with the levels on day 24 in the same animals but could not be used for prediction of large or small litters. The odds ratio for a small litter size was 0.16 (p < 0.01). This means that odds for a litter size <10 piglets decreased by 84% when E1S levels increased by 1.0 ng/ml. [ABSTRACT FROM AUTHOR]

Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea‐salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br−) by O2 and H2O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br−, O2 and H3O+ could spontaneously generate Br and HO2 radicals through a proton–electron transfer process at the air–water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br− and the production of Br2. The estimated gaseous Br2 production rate was up to 1.55×1010 molecules cm−2 ⋅ s−1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br− activation could promote the multiphase oxidation of SO2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br− activation. Our findings highlight the crucial role of the proton‐electron transfer process in Br2 production; here, H3O+ facilitates the activation of Br− by O2, serves as a significant source of atmospheric reactive bromine and exerts a profound impact on the atmospheric oxidation capacity. [ABSTRACT FROM AUTHOR]

The sulfur over calcium ratio (S/Ca) in foraminiferal shells was recently proposed as a new and independent proxy for reconstructing marine inorganic carbon chemistry. This new approach assumes that sulfur is incorporated into CaCO 3 predominantly in the form of sulfate (SO 4 2−) through lattice substitution for carbonate ions (CO 3 2–), and that S/Ca thus reflects seawater [CO 3 2–]. Although foraminiferal growth experiments validated this approach, field studies showed controversial results suggesting that the potential impact of [CO 3 2–] may be overwritten by one or more parameters. Hence, to better understand the inorganic processes involved, we here investigate S/Ca values in inorganically precipitated CaCO 3 (S/Ca (cc)) grown in solutions of CaCl 2 − Na 2 CO 3 − Na 2 SO 4 − B(OH) 3 − MgCl 2. Experimental results indicate the dependence of sulfate partitioning in CaCO 3 on the carbon chemistry via changing pH and suggest that faster precipitation rates increase the partition coefficient for sulfur. The S/Ca ratios of our inorganic calcite samples show positive correlation with modelled [CaSO 4 0] (aq) , but not with the concentration of free SO 4 2− ions. This challenges the traditional model for sulfate incorporation in calcite and implies that the uptake of sulfate potentially occurs via ion-ion pairs rather than being incorporated as single anions. Based on the [Ca2+] dependence via speciation, we here suggest a critical evaluation of this potential proxy. As sulfate complexation seems to control sulfate uptake in inorganic calcite, application as a proxy using foraminiferal calcite may be limited to periods for which seawater chemistry is well-constrained. As foraminiferal calcite growth is modulated by inward Ca2+ flow to the site of calcification coupled to outward H+ pumping, sulfate incorporation as CaSO 4 0 ion-pair in the foraminifer's shell also provides a mechanistic link for the observed relationship between S/Ca (cc) and [CO 3 2–]. [ABSTRACT FROM AUTHOR]

Phyllophorus proteus is a low-value sea cucumber from Indonesia and other tropical peripheral waters. In this study, a fucosylated glycosaminoglycan (FG) was extracted from P. proteus. It consists of GlcA, GalNAc, and Fuc, with a molecular weight of 67.1 kDa. The degraded FG (dFG) was prepared by β-elimination. Structural analysis revealed that the main chain of dFG was composed of GalNAc and GlcA, linked alternately by β1,3 and β1,4 glycosidic bonds. The sulfate group was located at the 4 and 6 positions of GalNAc. Fuc was attached to the 3 position of GlcA by an α1,3 glycosidic bond, and the side chain of Fuc exhibited various sulfate substitutions. FG significantly prolonged the coagulation time of APTT, PT, TT, and FIB, surpassing the effect of LMWH, thereby demonstrating its ability to exert anticoagulant effects in both the endogenous and exogenous coagulation pathways. Conversely, dFG had no significant effect on the clotting time of PT, suggesting its lack of impact on the intrinsic coagulation pathway. This study elucidates the structural properties and potent anticoagulant activities of fucosylated glycosaminoglycan from P. proteus. [ABSTRACT FROM AUTHOR]

Tetrahedral oxygenated groups with large highest occupied molecular orbital‐lowest unoccupied molecular orbital (H gaps such as [SO4] are beneficial for deep ultraviolet (DUV) transmission but usually make against generating sufficient birefringence due to the small polarizability anisotropy. Thus, it is extremely difficult to obtain DUV transmission and large birefringence simultaneously in the search for DUV birefringent materials in sulfates. Herein, two new ammonium‐rare earth metal sulfates, NH4Y(SO4)2·H2O and NH4YSO4F2, with DUV transmission are presented. Meanwhile, both exhibit greatly elevated birefringence through the involvement of NH4+ units, compared to Y2(SO4)3·8H2O. Their optical properties are further investigated by theoretical calculations, and the effect of the introduction of NH4+ into yttrium sulfate on optimizing the structures and properties is discussed. This work may provide a new perspective for further exploration of DUV birefringent materials in tetrahedral oxygenated group sulfates. [ABSTRACT FROM AUTHOR]

Objective: To compare the effects of occlusion and pharmacological penalization on visual acuity in the treatment of amblyopia. Material and Method: Thirty-nine patients followed up in our strabismus unit due to amblyopia were included in our study. The patients were randomly divided into two groups as occlusion and pharmacological penalization. and visual acuities of both groups were compared before and after treatment. All patients underwent a complete ophthalmological examination. In the occlusion group, alternating occlusion for 3 days in the healthy eye and 1 day in the amblyopic eye (3:1) for 6 months was applied for 1 to 6 hours, depending on the degree of amblyopia and the age of the patient, while pharmacological penalization was applied once a day to the healthy eyes of the patients with 1%. Atropine sulfate was instilled dropwise and continued for one month. Then, intermittent treatment was started and atropine was dripped into the healthy eye twice a week, and this treatment was continued for 6 months. Results: Pharmacological penalization therapy was applied to 19 of the patients (8 girls, 11 boys), and occlusion therapy was applied to 20 (8 girls, 12 boys). While the mean visual acuity of amblyopic eyes in the pharmacological penalization group was 0.15±0.07 according to the Snellen chart before the treatment, it was 0.41±0.17 at the 6th month after the treatment. The mean visual acuity of the amblyopic eye was increased by 0.26±0.13 with treatment (p <0.001). The visual acuity in amblyopic eyes in the occlusion group was 0.27±0.18 according to the Snellen chart before the treatment, and 0.40±0 .25 at the 6th month after the treatment. A mean increase of 0.22±0.11 was detected in the visual acuity of the amblyopic eyes (p <0.001). There was no statistically significant difference between the visual acuity improvement rates of the two groups (p >0.05). Conclusion: In our study, occlusion and pharmacological penalization applied in the treatment of amblyopia were found to be effective at a rate similar to the increase in visual acuity, Penalization of atropine should be kept in mind in children who do not comply with occlusion therapy. [ABSTRACT FROM AUTHOR]

The source of sulfuric acid and associated aqueous alteration of ancient martian sedimentary rocks remain under debate in the context of divergent models of jarosite formation. Here, we report the formation of sulfates, including jarosite in K-bentonites within shallow-water facies of the Permian-Triassic (P-T) transition at Xiakou in South China. In these strata, jarosite is dispersed in the clay matrix or forms aggregates in pore spaces, has a euhedral morphology, and coexists with variably 34S-depleted paragenetic gypsum and bassanite (δ34S = –37.23‰ to +3.20‰ VCDT). Subaqueous alteration of volcanic tuffs concurrently with oxidation of upwelled, biogenically sourced H2S is the process of jarosite formation in the Xiakou K-bentonites. This mechanism of jarosite precipitation and stability over geological time challenges the long-held view of acidic, water-limited conditions leading to iron(III) sulfate precipitation and would be consistent with possible microbial or nanobial life on early Mars. [ABSTRACT FROM AUTHOR]

Additives are very important to enhance the performance of lead-acid batteries. In this paper, formic acid is used as an electrolyte additive to study its effect on battery performance. The results show formic acid has an opposite effect on the electrochemical properties of pure lead at positive and negative potentials. Besides, formic acid can make more active materials participate in the reaction, increase the rate of conversion of lead to lead sulfate, and reduce the internal resistance of the battery. Moreover, formic acid batteries exhibit better rate performance and higher specific discharge capacity than the blank. Especially, when the 0.5 wt% formic acid is used, the discharge capacity can reach 87.0 mAh g−1 when it is discharged at 400 mA g−1. After 1200 cycles of charge and discharge at a current density of 100 mA g−1, the specific discharge capacity is still 68.1 mAh g−1, which is 1.42 times higher than that of blank cells. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF)–chondroitin sulfate (CS)-hybrid hydrogels (HHGs) containing kartogenin (KGN) were synthesized by the induction of di-tyrosine bonds, using enzymatic crosslinking in SF/CS blend solution. Then, physical crosslinking was performed to optimize the HHG properties. The results showed that the increasing of the β-sheet content as side effect of physical crosslinking from 10% to 40% affects KGN accumulative release percentage almost three times. Biological investigations using C28/I2 human chondrocyte cell line showed that the presence of KGN, CS, and optimized β-sheets content improved cell supporting behavior of HHG. Finally, KGN loaded HHG might be a promising candidate for cartilage repair. Schematic representation of fabrication of the dual crosslinked hybrid hydrogel containing silk fibroin and chondroitin sulfate by enzymatic crosslinking and physical crosslinking method for kartogenin release. Enzymatic crosslinking: shaping di-tyrosine formation bond between silk fibroin phenol groups and locking physically chondroitin sulfate between silk fibroin β-sheets. Physical crosslinking with water and/or ethanol treatments end up in increased β-sheets content. [ABSTRACT FROM AUTHOR]

In vitro biomineralization, carried out under laboratory conditions, provides scope for highly controlled crystallization events, at different stages of the formation reaction. This crystallization control is exerted using foreign substances or additives, which are usually organic compounds. Here, we have shown how with the use of homeopathic medicine Symphytum Q, the morphology of calcium carbonate is changed from its rhombohedral, the most stable morphology to spherical morphology, while the phase remains the same. A study has also been done on the formation of gypsum with varying parameters. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sulfate metabolites of endogenous anabolic androgenic steroids (EAAS) have been shown to prolong the detection times compared with the conventional urinary markers of the steroid profile for oral and intramuscular administrations of testosterone (T). In this work, the sensitivity of sulfate EAAS markers for the detection of T gel administration has been evaluated in six Caucasian and six Asian male volunteers. Fourteen sulfate metabolites were measured in basal and post‐administration samples after multiple doses of T gel (100 mg/day, three consecutive days), and the detection times based on individual thresholds for each volunteer were evaluated. Sulfate concentrations did not show adequate sensitivity, but the results of sulfate ratios were much more promising. Androsterone sulfate/testosterone sulfate (A‐S/T‐S), epiandrosterone sulfate/epitestosterone sulfate (epiA‐S/E‐S), epiA‐S/T‐S, and etiocholanolone sulfate/epitestosterone sulfate (Etio‐S/E‐S) provided the most consistent detectability for all volunteers and populations, with detection times ranging from 60 to 96 h since the first dose. Additional ratios improved detectability to up to 7 days, but only in particular volunteers. In general, sensitivity was similar to or better than the conventional testosterone/epitestosterone ratio (T/E) of the steroid profile, which further reinforces the conclusion that sulfate EAAS metabolites can be a good complement for the current steroid profile. [ABSTRACT FROM AUTHOR]

Nickel (Ni) is an interesting candidate for corrosion protection of copper (Cu) due to its present passive area. Ni films with larger passive areas have better corrosion protection than those with smaller ones. In the present research, Ni films were produced over Cu. A barreling apparatus was employed to support the produced films in the sulphate solution. Various spinning speeds (0, 50, and 100 rpm) were used on the barrel while it was being processed. Several investigations were conducted, such as deposition rate, current efficiency, surface morphology, phase, film thickness, crystallographic orientation, and electrochemical properties. Increased spinning speed resulted in a decrease in the deposition rate, current efficiency, grain size, thickness, crystallite size, and exchange current density. Compared to a higher spinning speed, the decrease in spinning speed caused an increase in the oxygen content, surface roughness, and micro-strain. The higher speed of the barrel apparatus resulted in a lower corrosion rate Ni film of 0.147 mmpy. Moreover, the lower speed of the barrel apparatus resulted in a higher exchange current density Ni film of 0.997 A/cm². [ABSTRACT FROM AUTHOR]

Degradation efficiency of 4-bromo-2-chlorophenol (BCP) containing both chlorine and bromine substituents in Co/PMS process was investigated in the light of a wide range of substrate, oxidant, catalyst concentrations and pH value. The effects of chloride ion (Cl−) on degradation kinetics, total organic carbon (TOC) removal and intermediates formation during BCP depletion in Co/PMS system were studied. The kinetics results demonstrated that the dual effect of Cl− on BCP depletion in Co/PMS system due to different mechanisms involved. High concentrations of Cl− (>5 mM) can significantly promote the degradation of BCP, but did inhibit BCP mineralisation to a certain extent which was closely related to Cl− content. High degradation rates but lower mineralisation rates were found in the laboratory experiments, owing to the fact that BCP was mainly transformed to new halogenated intermediates instead of complete mineralisation. Gas chromatograph-mass spectrometer (GC-MS) data verified that a series of chlorinated by-products were formed during BCP decomposition process involving of the participation of Cl−. The proposed degradation pathways of BCP and its derivatives in presence of Cl− were discussed on the basis of intermediate products including the undesirable halogenated by-products recognised by GC-MS. These results might offer some new perspectives on the transformation fates of BCP by utilising Co/PMS regent. [ABSTRACT FROM AUTHOR]

Steroids can be used as biomarkers in clinical metabolomics and other fields related to human toxicology. This chemical group is known for its complexity, considering its number of isobaric compounds and the wide variety of phases I and II metabolic pathways that parent compounds can undergo. For a successful analysis of steroids in biological samples, liquid chromatography separation must be finely tuned. It is especially challenging for glucuronidated and sulfated steroids derivatives that bear polar heads and can be affected by non‐specific adsorption. The benefits of a biphenyl stationary phase chemistry for the selectivity of the separation of steroids and their phase II metabolites and the extent to which nonspecific adsorption phenomena could degrade chromatographic performance were investigated. Replacing a conventional hardware by a passivated hardware allowed to considerably reduce peaks width and asymmetry of sulfated species. The addition of weak ion pairing agents in the mobile phase could also help to reduce non‐specific adsorption but are detrimental to mass spectrometry detection. As confirmed by the successful detection of 52 steroids in plasma, the use of a biphenyl stationary phase complemented by a passivated column hardware is of great help for a successful biomedical analysis of steroids and their phase II metabolites. [ABSTRACT FROM AUTHOR]

Background: H2S imbalances in the intestinal tract trigger Crohn's disease (CD), a chronic inflammatory gastrointestinal disorder characterized by microbiota dysbiosis and barrier dysfunction. However, a comprehensive understanding of H2S generation in the gut, and the contributions of both microbiota and host to systemic H2S levels in CD, remain to be elucidated. This investigation aimed to enhance comprehension regarding the sulfidogenic potential of both the human host and the gut microbiota. Results: Our analysis of a treatment-naive CD cohorts' fecal metagenomic and biopsy metatranscriptomic data revealed reduced expression of host endogenous H2S generation genes alongside increased abundance of microbial exogenous H2S production genes in correlation with CD. While prior studies focused on microbial H2S production via dissimilatory sulfite reductases, our metagenomic analysis suggests the assimilatory sulfate reduction (ASR) pathway is a more significant contributor in the human gut, given its high prevalence and abundance. Subsequently, we validated our hypothesis experimentally by generating ASR-deficient E. coli mutants ∆cysJ and ∆cysM through the deletion of sulfite reductase and L-cysteine synthase genes. This alteration significantly affected bacterial sulfidogenic capacity, colon epithelial cell viability, and colonic mucin sulfation, ultimately leading to colitis in murine model. Further study revealed that gut microbiota degrade sulfopolysaccharides and assimilate sulfate to produce H2S via the ASR pathway, highlighting the role of sulfopolysaccharides in colitis and cautioning against their use as food additives. Conclusions: Our study significantly advances understanding of microbial sulfur metabolism in the human gut, elucidating the complex interplay between diet, gut microbiota, and host sulfur metabolism. We highlight the microbial ASR pathway as an overlooked endogenous H2S producer and a potential therapeutic target for managing CD. Dka3P5uGJeBhH66pkNJcog Video Abstract [ABSTRACT FROM AUTHOR]

The characteristics and hazards of acid coal mine drainage (ACMD) were introduced, and the treatment methods of ACMD were described. Techniques that could be used for source prevention and process containment were analyzed. The widely used terminal treatment technologies at present were summarized, such as the active treatment technology based on neutralization, sulfidation, adsorption and membrane technology, and the passive treatment technology based on chemical, biological and chemical-biological combined method. It was summarized and concluded that the multi-technology combination process was the main trend of engineering application and an effective way for large-scale collaborative treatment of ACMD. Finally, the development prospect of ACMD treatment method was prospected. [ABSTRACT FROM AUTHOR]

An investigation into the effects of external sulfate attack (ESA) on the mechanical and microstructural properties of steel fibre-reinforced sprayed concrete (SFRSC) was conducted. Crimped carbon steel fibres, 40 mm long, were used as reinforcement in three different mixtures with specified fibre contents of 30, 60 and 90 kg/m3. Cylindrical specimens, drilled from SFRSC panels, were subjected to sulfate attack for up to 270 days. Double-punch tests were used to determine the matrix crack strength and the post-crack tensile strength of the SFRSC. The effective fibre content of each specimen was determined by inductive tests and subsequently correlated with the mechanical results. Scanning electron microscopy was used to evaluate the phases formed in the concrete pores during the ESA. The results showed that fibre reinforcement may reduce cracking due to ESA. [ABSTRACT FROM AUTHOR]

The article focuses on the role of microbial sulfate reduction (MSR) in carbon sequestration within marine sediments. It examines how MSR contributes to the formation of authigenic carbonates, enhances organic carbon retention through organic sulfur formation, and influences overall carbon burial efficiency. It highlights its significance in long-term carbon storage and climate regulation, particularly in the context of expanding anoxic zones due to climate change.

This study examined the associations of long-term exposure to ambient fine particulate matter (PM2.5) compositions/ozone with methylation of peripheral brain-derived neurotrophic factor (BDNF) promoters. A total of 101 participants were recruited from a cohort in Shijiazhuang, Hebei province, China. They underwent baseline and follow-up surveys in 2011 and 2015. DNA methylation levels were detected by bisulfite-PCR amplification and pyrosequencing. Participants' three-year average levels of PM2.5 compositions and ozone were estimated. Bayesian kernel machine regression (BKMR) models were used to examine the joint effects of pollutants on methylation levels. Exposure to PM2.5 compositions and ozone mixtures at the 75th percentile was associated with increased methylation levels at CpG2 of BDNF promoter (203%, 95% CI: 89, 316) than the lowest level of exposure, and sulfate dominated the effect in the BKMR models.Our findings provide clues to the epigenetic mechanisms for the associations of PM2.5 compositions and ozone with BDNF. [ABSTRACT FROM AUTHOR]

Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks. Nevertheless, the impact of sulfate concentration on the desorption of oil film on the surface of carbonate rock is still unknown. This study examines the variations in the wettability of the surface of carbonate rocks in solutions containing varying amounts of sodium sulfate and pure water. The problem is addressed in the framework of molecular dynamics simulation (Material Studio software) and experiments. The experiment's findings demonstrate that sodium sulfate can increase the rate at which oil moisture is turned into water moisture. The final contact angle is smaller than that of pure water. The results of the simulations show that many water molecules travel down the water channel under the influence of several powerful forces, including the electrostatic force, the van der Waals force and hydrogen bond, crowding out the oil molecules on the calcite's surface and causing the oil film to separate. The relative concentration curve of water and oil molecules indicates that the separation rate of the oil film on the surface of calcite increases with the number of sulfate ions. Graphic Abstract [ABSTRACT FROM AUTHOR]

To provide a theoretical basis for reducing thaumasite sulfate attack (TSA) and enhancing ground limestone utilization in cement-ground limestone cementitious materials, this study examines the mechanisms underlying thaumasite formation and its relationship with temperature, cations, and ground limestone, utilizing thermodynamic principles. The findings indicate that thaumasite formation is constrained above 60.35 °C. Between 48.15 and 60.35 °C, only direct route is feasible, while below 48.15 °C, both direct and woodfordite routes occur spontaneously. As temperature decreases, Gibbs free energy changes decrease for both routes, promoting thaumasite formation. Mg2+ facilitates thaumasite formation via woodfordite route, while Na+ promotes it via direct route. With both Mg2+ and Na+ present, thaumasite formation depends on Na+ to Mg2+ ratio: below 5 favors woodfordite route, exceeding 5 favors direct route. Ground limestone reduces sulfate required for thaumasite formation, favoring the woodfordite route and exacerbating TSA; however, excessive ground limestone has a dilution effect on cement, thereby reducing thaumasite formation. [ABSTRACT FROM AUTHOR]

Aerosols deposited on the surfaces of alloys and coatings used in high-temperature applications react with the protective thermally grown oxide (TGO) and accelerate component degradation. Understanding how the TGO composition effects these reactions is essential to develop corrosion-resistant materials. This work studies the corrosion of Haynes-214 alloy, which forms a bilayer Ni(Cr,Al)2O4 (spinel) + Al2O3 TGO, exposed to complex oxide and sulfate deposits to understand how the Cr and Ni oxides affect the corrosion mechanisms. The deposit compositions were systematically varied to understand the effect of anion makeup (mixed oxides, oxide-sulfate, and sulfates). The results are compared to a FeCrAlY alloy that forms a simple Al2O3 TGO. On the Haynes-214 alloy, deposits containing mixed oxides (with or without sulfates) have limited corrosive effect. In contrast, a pure CaSO4 deposit reacts aggressively with the TGO to form calcium chromate and aluminate reaction products (RP) that substantially increase the TGO + RP thickness compared to that on the FeCrAlY alloy. Surprisingly, a deposit composed of a mixture of sulfates caused less severe corrosion than the CaSO4 alone since magnesium chromate formation appears to limit aggressive reactions involving Ca. The results are discussed in the context of opportunities for corrosion-resistant alloy design. [ABSTRACT FROM AUTHOR]

Antimonate (Sb(V)), sulfate and acid orange 7 (AO7) are common pollutants in printing and dyeing wastewater. Currently, there have been no reports about the effects of sulfate and AO7 on Sb(V) removal by anaerobic granular sludge (AnGS). In this study, the Sb(V) removal and Sb(Ш) accumulation was revealed in presence of sulfate and AO7, and the role of adding granular activated carbon (GAC) was investigated. Results showed that sulfate inhibited Sb(V) removal by AnGS (S + Sb, k = 0.101). GAC alleviated the inhibition of sulfate on Sb(V) removal and Sb(V) removal rate increased by 1.9 times (GAC + S + Sb, k = 0.187). Meanwhile, GAC promoted sulfate reduction by AnGS. AO7 inhibited sulfate reduction, thereby alleviating the inhibition of sulfate on Sb(V) removal, and Sb(V) removal rate increased by 1.5 times (S + Sb + dye, k = 0.147). When Sb(V), sulfate and AO7 coexisted, adding GAC actually inhibited Sb(V) removal (GAC + S + Sb + dye, k = 0.067), which may be due to GAC promoted the reduction of sulfate and AO7 by AnGS. The microbial community analysis revealed that Acinetobacter genus was related to Sb(V) reduction, with higher relative abundance in GAC + S + Sb (49.4%) and S + Sb + dye groups (28.9%). These results provided guidance for anaerobic treatment of printing and dyeing wastewater. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)