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Due to vincristine sulfate's (VCR sulfate) toxicity and non-specific targeting, which might adversely damage healthy cells, its clinical application is restricted. In this study, we loaded VCR sulfate on exosomes generated from mesenchymal stem cells (MSCs) to enhance its targeted distribution. Exosomes are able to deliver molecules to specific cells and tissues and have therapeutic potential. In this study, we isolated exosomes from MSCs, and using probe-sonication approach loaded them with VCR sulfate. Using SRB assay, the cytotoxicity of VCR sulfate-Exo was assessed in T47D breast cancer cells, and the results were contrasted with those of free VCR sulfate. Then We labeled markers (CD44+/CD24−) in the cell line to assess the targeting effectiveness of VCR sulfate-Exo using flow cytometry. Our results showed that the cytotoxicity of VCR sulfate-Exo was nearly the same as that of VCR sulfate. Flow cytometry analysis revealed that VRC sulfate-Exo was more effectively targeted to MSCs than free VCR sulfate. Our study shows that loading VCR sulfate to MSCs-derived exosomes can improve their targeted delivery and lessen their side effects. Additional research is required to determine VCR sulfate-Exo's in vivo effectiveness and safety and improve the loading and delivery strategies. [ABSTRACT FROM AUTHOR]

The surface of Venus is in contact with a hot (~470 °C), high pressure (92 bars), and caustic (CO2 with S, but little H2O) atmosphere, which should cause progressive alteration of the crust in the form of sulfate and iron-oxide coatings; however, the exact rate of alteration and mineral species are not well constrained. Different experimental approaches, each with its own limitations, are currently being used to constrain mineralogy and alteration rates. One note is that no experimental approach has been able to fully replicate the necessary conditions and sustain them for a significant length of time. Furthermore, geochemical modeling studies can also constrain surface alteration mineralogy, again with different assumptions and limitations. Here, we review recent geochemical modeling and experimental studies to constrain the state of the art for alteration mineralogy, rate of alteration, open questions about the surface mineralogy of Venus, and what can be constrained before the fleet of missions arrives later this decade. Combining the new results confirms that basalt on the surface of Venus should react quickly and form coatings of sulfates and iron-oxides; however, the mineralogy and rate of alteration are dependent on physical properties of the protolith (including bulk composition, mineralogy, and crystallinity), as well as atmospheric composition, and surface temperature. Importantly, the geochemical modeling results show that the mineralogy is largely controlled by atmospheric oxygen fugacity, which is not well constrained for the near-surface environment on Venus. Therefore, alteration experiments run over a range of oxygen and sulfur fugacities are needed across a wide range of Venus analog materials with varying mineralogy and crystallinity. [ABSTRACT FROM AUTHOR]

Sulfate surfactants in cosmetic products raise concerns due to their skin irritating impact and sustainability. Rhamnolipid, a green and safe biosurfactant, was studied from the perspective of rheology to help develop a formulation with natural and effective ingredients for cosmetics. The viscosity of rhamnolipids was investigated by changing pH, concentration and adding additives like inorganic salts (NaCl, MgCl2) and polymers (Carbopol® Ultrez 20, Carbopol® Aqua SF‐1, Carbopol® 940 and cationic guar gum), showing that the viscosity of rhamnolipid had a positive correlation with the increase of concentration, a negative correlation with the increase of pH, and that polymers instead of inorganic salts were suitable for thickening rhamnolipid. Further rheology tests indicated that Carbopol® Aqua SF‐1 imparted gel properties of rhamnolipid while cationic guar gum determined the liquid properties. In addition, the rhamnolipid‐containing moisturizing cream consisting of stearic acid/squalane ratios all showed shear‐thinning and gel behavior the same as the commercial ones. Visual appearance and particle size analysis indicated that all formulations exhibited high storage stabilities. The knowledge gained from this study may be useful for designing "sulfonate‐free" shampoo and cream with rheological properties that can be tailed for specific commercial cosmetic applications. [ABSTRACT FROM AUTHOR]

Through microscopic analyses (e.g., organic macerals, thin section observation, scanning electron microscope (SEM) imaging of fresh bedding planes via argon ion milling, and energy spectrum tests) combined with Rock-Eval analyses, this study systematically investigated the organic matter and pyrites in the continental shales in the 3rd submember of the Chang 7 Member (Chang 7³ submember) in the Yanchang Formation, Ordos Basin and determined their types and the formation and evolutionary characteristics. The results are as follows. The organic matter of the continental shales in the Chang 7³ submember is dominated by amorphous bituminites and migrabitumens, which have come into being since the early diagenetic stage and middle diagenetic stage A, respectively. The formation and transformation of organic matter is a prerequisite for the formation of pyrites. The Ordos Basin was a continental freshwater lacustrine basin and lacked sulphates in waters during the deposition of the Chang 7 Member. Therefore, the syndiagenetic stage did not witness the formation of large quantities of pyrites. Since the basin entered early diagenetic stage A, large quantities of sulfur ions were released as the primary organic matter got converted into bituminites and, accordingly, pyrites started to form. However, this stage featured poorer fluid and spatial conditions compared with the syndepositional stage due to withdraw of water, the partial formation of bituminites, and a certain degree of compaction. As a result, large quantities of pyrrhotite failed to transition into typical spherical framboidal pyrites but grew into euhedral monocrystal aggregates. In addition, pyrites are still visible in the migrabitumens in both microfractures and inorganic pores of mudstones and shales, indicating that the pyrite formation period can extend until the middle diagenetic stage A. [ABSTRACT FROM AUTHOR]

The Beckmann rearrangement of ketoximes to their corresponding amides, using a Brønsted acid-mediated fragmentation and migration sequence, has found wide-spread industrial application. We postulated that the development of a methodology to access ylideneamino sulfates using tributylsulfoammonium betaine (TBSAB) would afford isolable Beckmann-type intermediates and competent partners for subsequent rearrangement cascades. The ylideneamino sulfates generated, isolated as their tributylammonium salts, are sufficiently activated to undergo Beckmann rearrangement without additional reagent activation. The generation of sulfuric acid in situ from the ylideneamino sulfate giving rise to a routine Beckmann rearrangement and additional amide bond cleavage to the corresponding aniline was detrimental to reaction success. The screening of bases revealed inexpensive sodium bicarbonate to be an effective additive to prevent classic Brønsted acid-mediated fragmentation and achieve optimal conversions of up to 99%. [ABSTRACT FROM AUTHOR]

The C(sp2)-aryl sulfonate functional group is found in bioactive molecules, but their synthesis can involve extreme temperatures (>190 °C or flash vacuum pyrolysis) and strongly acidic reaction conditions. Inspired by the 1917 Tyrer industrial process for a sulfa dye that involved an aniline N(sp2)-SO3 intermediate en route to a C(sp2)-SO3 rearranged product, we investigated tributylsulfoammonium betaine (TBSAB) as a milder N-sulfamation to C-sulfonate relay reagent. Initial investigations of a stepwise route involving TBSAB on selected anilines at room temperature enabled the isolation of N(sp2)-sulfamate. Subsequent thermal rearrangement demonstrated the intermediary of a sulfamate en route to the sulfonate; however, it was low-yielding. Investigation of the N-sulfamate to C--sulfonate mechanism through control experiments with variation at the heteroatom positions and kinetic isotope experiments (KIEH/D) confirmed the formation of a key N(sp2)-SO3 intermediate and further confirmed an intermolecular mechanism. Furthermore, compounds without an accessible nitrogen (or oxygen) lone pair did not undergo sulfamation- (or sulfation) -to-sulfonation under these conditions. A one-pot sulfamation and thermal sulfonation reaction was ultimately developed and explored on a range of aniline and heterocyclic scaffolds with high conversions, including N(sp2)-sulfamates (O(sp2)-sulfates) and C(sp2)-sulfonates, in up to 99 and 80% (and 88% for a phenolic example) isolated yield, respectively. Encouragingly, the ability to modulate the ortho-para selectivity of the products obtained was observed under thermal control. A sulfonated analog of the intravenous anesthetic propofol was isolated (88% yield), demonstrating a proof-of-concept modification of a licensed drug alongside a range of nitrogen- and sulfur-containing heterocyclic fragments used in drug discovery. [ABSTRACT FROM AUTHOR]

Sonopiezoelectric therapy (SPT) has gained ever‐increasing prominence in tumor therapy as a combination of ultrasound (US) and piezoelectric nanomaterials to generate cytotoxic reactive oxygen species (ROS) for tumor suppression. In this study, the facile hydrothermal method is used to construct the distinct 2D piezocatalyst Bi2Fe4O9 nanosheets (BFO NSs). The engineered BFO NSs can create a piezoelectric field when exposed to US irradiation, facilitating the separation of electron–hole (e−–h+) pairs to play a crucial role in Fe3+/Fe2+ circulation, which catalyzes the activation of peroxymonosulfate (PMS), resulting in an amplified production of cytotoxic sulfate radical (SO4•−). The produced SO4•− combines with ROS generated by SPT including hydroxyl radicals (•OH), and singlet oxygen (1O2), leading to the augmented oxidative tumor suppression. The BFO NSs and PMS are further integrated into a thermal hydrogel (BFO/PMS‐Gel) for in vitro and in vivo investigations on their catalytic antitumor effects. In both in vitro and in vivo studies, it is validated that BFO/PMS‐Gel, under US irradiation, significantly enhances radicals generation efficiency, which achieves superior antitumor performance while maintaining high therapeutic biocompatibility and biosafety, providing a representative paradigm of US‐activated multiple radicals production as enabled by piezoelectric nanomedicine for antitumor treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel sulfates supported binary RuIrO x be synthesized. • A strong catalyst-support interaction between RuIrO x and BaSrSO 4. • The RuIrO x /BSS exhibits a high OER mass activity of only 324 mV overpotential at 1000 A/g Ru + Ir. • It shows outstanding CER activity and stability. Electrolysis for producing hydrogen powered by renewable electricity can be dramatically expanded by adapting different electrolytes (brine, seawater or pure water), which means the anode materials must stand up to complex electrolyte conditions. Here, a novel catalyst/support hybrid of binary Ru 3.5 Ir 1 O x supported by barium strontium sulfate (BaSrSO 4) was synthesized (RuIrO x /BSS) by exchanging the anion ligands of support. The as-synthesized RuIrO x /BSS exhibits compelling oxygen evolution (OER) and chlorine evolution (CER) performances, which affords to 10 mA cm−2 with only overpotential of 244 mV and 38 mV, respectively. The performed X-ray adsorption spectra clearly indicate the presence of an interface charge transfer effect, which results in the assignment of more electrons to the d orbitals of the Ru and Ir sites. The theoretical calculations demonstrated that the electronic structures of the catalytic active sites were modulated to give a lower overpotential, confirming the intrinsically high OER and CER catalytic activity. [ABSTRACT FROM AUTHOR]

This paper investigates the tensile behaviors and self-healing of engineered cementitious composite (ECC) under sulfate wet–dry cycles to reflect the durability. Four pretensile strain levels of 0%, 1%, 1.5%, and 2% were designed. The uniaxial tensile test, three-point bending test, and single-crack tensile test were performed, along with the microscopic characterizations of scanning electron microscope (SEM) and X-ray diffraction (XRD). The results indicated that the sulfate wet–dry cycle exposure had a positive effect on the tensile strength and initial cracking strength of the uncracked ECC, while that was negative on the tensile strain capacity. The insufficient margin of the σoc/σcr and Jb′/Jtip indices explained the lower tensile strain. The tensile strength and initial cracking strength of the cracked ECC with 1% pretensile strain surpassed those of the uncracked ECC after undergoing 80 sulfate wet–dry cycles (80 C), while that did not hold for the other cracked ECCs. All the cracked ECCs showed a similar tensile strain after undergoing 80 C. The crack with a width of less than 100 μm achieved complete self-healing. The self-healing products of ECC under sulfate wet–dry cycle exposure may comprise of calcium (alumino) silicate hydrate [C-(A)-S-H] gel, calcite, ettringite, and gypsum. The current findings could offer reference points for applying ECC use in coastal regions. [ABSTRACT FROM AUTHOR]

A rapid and efficient analytical method was established to quantify indoxyl sulfate (IS) in plasma through extraction technique with a deep eutectic solvent (DES) and spectrofluorimetric method. DES (choline chloride: urea) was mixed with plasma samples for the extraction of IS, followed by the addition of dipotassium hydrogen phosphate (K2HPO4) solution to form an aqueous two-phase system. The fluorescence intensity of IS which was first extracted to the DES-rich-phase and then back-extracted into the salt-rich-phase, was measured by spectrofluorimetric method. Some key factors such as pH, centrifugation speed and time, the volume ratio of DES/salt, and salt concentration were optimized. Under the optimized conditions, the suggested method had a dynamic range between 20 and 160 µg/mL with a coefficient of determination (R2) of 0.99. Precision (relative standard deviation) was less than 15% and accuracy (% relative recovery) was ± 15% at the nominal concentration level. In addition, results showed that IS levels in real samples were higher than 40 µg/mL which was compatible with reported IS levels in end-stage renal disease (ESRD) patients. Overall, all the results reflect the fact that the presented analytical method can potentially be used for the determination of IS in real plasma samples. [ABSTRACT FROM AUTHOR]

Salt crystallization is one of the most important factors causing weathering in grottoes. Cumulative crystallization of salts causes damage such as flaking and peeling of the rocks and accelerates the weathering processes of the grottoes. The accumulated crystalline salts cause spalling, skinning and other damage and accelerate the weathering process of the grotto rock body. It is necessary to study the existing glutenite rock grottoes. This paper took the glutenite rock of the Maijishan Grottoes as a case study, and Na2SO4 or MgSO4 solutions were applied to glutenite rock specimens subjected to different deterioration cycles. The crystallization patterns of the two different salts and their damage to the glutenite rock were analyzed and studied, the mechanism for salt crystallization damage to the glutenite rock was explored, and the crystallization pressures of the two salts in the glutenite rock were derived with theoretical calculations. The results showed that both Na2SO4 and MgSO4 crystallization damaged the glutenite rock, and the former different sulfate solutions changed at different rates, and the changes in the wave caused faster damage than the latter. The physical indices of the rock samples in the velocities and tensile strengths were consistent. Na2SO4 was mainly accumulated on the surface of the specimen and damaged the glutenite rock centripetally via pulverization and exfoliation. MgSO4 mainly crystallized inside the glutenite rock, which created internal fissures and reduced the strength of the rock. The theoretical maximum crystallization pressures of Na2SO4 and MgSO4 in the glutenite rock specimens reached 33.00 MPa and 9.94 MPa, respectively. This study provides a theoretical basis for studies of salt crystallization in glutenite rock grottoes and provides a method for protecting the stones in cultural heritage sites against weathering. [ABSTRACT FROM AUTHOR]

This paper investigates comprehensively the operational dynamics of a thermochemical heat storage (TCHS) reactor for low-temperature applications using polyaluminum sulfate and takes into consideration a developed simulation model with an experimentation validation. Significant concordances were found between the developed simulation model and the experimental results. Results reveal optimized conditions for the charging process using an electrical heater, with a heating temperature of 120°C at 10 K/min over 500 minutes. This achieves full material charging, with stabilized pressure drops at an equilibrium of 80 mbar, corresponding to a temperature of approximately 108°C, and yielding a thermal power of 950 W. An inlet vapor pressure of 18 mbar at 10°C for 5 hours is sufficient to completely discharge the bed, with pressure drops reaching around 30 mbar and a thermal power of 300 after reaction completion. Insights into conversion extents during both processes are provided, along with a remarkable thermal efficiency of 90% and a coefficient of performance (COP) of 97%, surpassing recommended theoretical values (50%). The study suggests further enhancing system performance through the design and implementation of a dedicated heat exchanger. The achievement of 75% of the targeted thermal power specification represents a significant milestone, offering valuable contributions towards the realization of sustainable technological advancements of both the reactor technology of TCHS and state-of-the-art thermal energy storage solutions. From the research, it is possible to infer further suggestions for enhancing this performance by designing and implementing a dedicated heat exchanger for both heat supply and retrieval mechanisms. [ABSTRACT FROM AUTHOR]

In this study, a sulfonation approach using chlorosulfonic acid (CSA) to prepare cellulose sulfate nanofibers (CSNFs) from raw jute fibers is demonstrated. Both elemental sulfur content and zeta potential in the CSNFs are found to increase with increasing CSA content used. However, the corresponding crystallinity in the CSNFs decreases with the increasing amount of CSA used due to degradation of cellulose chains under harsh acidic conditions. The ammonium adsorption results from the CSNFs with varying degrees of sulfonation were analyzed using the Langmuir isotherm model, and the analysis showed a very high maximum ammonium adsorption capacity (41.1 mg/g) under neutral pH, comparable to the best value from a synthetic hydrogel in the literature. The high ammonium adsorption capacity of the CSNFs was found to be maintained in a broad acidic range (pH = 2.5 to 6.5). [ABSTRACT FROM AUTHOR]

In this study, Afşin Elbistan C-type fly ash (FA) was used, which protects against the sulphate reaction that damages concrete. The detrimental effects of post-reaction decrease with increasing fly ash fineness. The study used 10%, 30%, and 50% weight substitutes of cement. The fly ash was ground in a ball mill for 0, 10, 20, 30, 45, and 60 min, and Blaine fineness values of 1555, 1632, 2347, 2589, 2766, and 3433 cm2/g were obtained, respectively. The effect of the samples on the sulphate resistance was investigated by exposing the samples to 5% or 10% added sulphate solutions, and the compressive strength and ultrasonic pulse velocity of the concrete were tested. The compressive strength values obtained decreased with the increase in sulphate content, and the increase in the grinding time and the amount of substituted FA increased the compressive strength values. It was observed that weight loss increased with increasing sulphate content and decreased with the addition of FA with a high Blaine fineness. It was determined that as the Blaine fineness value increased, the sulphate content, FA substitution amount, and ultrasonic pulse speed decreased. This study was carried out to determine the effects of fly ash used at different fineness and replacement ratios on the performance and strength of concrete after exposure to external influences such as sulphate. The use of fly ash instead of cement will reduce the use of waste materials and natural resources and prevent environmental pollution. The cost of cement and concrete will be reduced. [ABSTRACT FROM AUTHOR]

The α-calcium sulfate hemihydrate whiskers (α-CSHWs) were first prepared using phosphogypsum (PG) and electrolytic manganese residue (EMR) as raw materials for coating urea, demonstrating excellent controlled-release properties. The effects of different reaction conditions on α-CSHWs, achieved by optimizing the reaction time, the concentrations of NH4+, Mn2+, and other factors, were discussed. Results showed that when the EMR content was 25 wt%, the reaction temperature was 100 °C, and the reaction time was 3 h, α-CSHWs with a length-to-diameter ratio of 39 were obtained. Through experiments and density functional theory (DFT), the mechanism of α-CSHWs preparation was elucidated. The results show that the addition of EMR reduces the content of impurity ions PO43− and F− in PG while introducing NH4+ and Mn2+. Interestingly, both NH4+ and Mn2+ can reduce the nucleation time of α-CSHWs, while PO43−, Mn2+, and F− are more likely to adsorb on the (0 0 6) crystal plane of α-CSHWs, NH4+ readily adsorbs on the (4 0 0) crystal plane. The controlled-release performance of modified α-CSHWs incorporated into polyurethane-coated urea (PCU) was investigated, and it was found that the addition of Mα significantly prolonged the nutrient release period, with the period extending up to 116 days for coatings of 5wt% and above. This work not only enhances the efficiency of PG and EMR utilization but also serves as a reference for the straightforward synthesis and application of α-CSHWs. [ABSTRACT FROM AUTHOR]

Background Bowel cleansing is an important factor for the quality of colonoscopy. We aimed to evaluate the efficacy of split-dose oral sulfate salts on bowel preparation and to determine parameters influencing the quality of bowel cleaning. Method Consecutive adults who completed their preparation for colonoscopy with a regimen of sulfate salts were enrolled. Results Of the 446 patients, 11 were excluded from the analysis. Among the 435 patients, 257 (59.1%) were female, mean age was 62.0±11.6 years and median body mass index (BMI) 26.1 kg/m2 (interquartile range [IQR] 23.8-29.4). Indications for colonoscopy were screening 155 (35.6%), surveillance 102 (23.5%), or other 178 (40.9%). The median time between the end of second dose of the preparation regimen and colonoscopy initiation was 5:15 h (IQR 4:30-6:00, min: 2:20, max: 12:20). Minor adverse events were reported in 62 (14.3%) patients. BBPS=9 was observed in 279 (64.14%) patients. Segmental BBPS=3 was achieved in 387 (88.97%), 346 (79.54%) and 289 (66.44%) patients (P<0.001) in the descending, transverse and ascending colon, respectively. Multivariate analysis revealed that BMI (odds ratio [OR] 1.05, 95% confidence interval [CI] 1-1.1) and time between the end of the second laxative dose and colonoscopy initiation (OR 1.25, 95%CI 1.08-1.45) were associated with poorer bowel preparation. Conclusions A split dose of oral sulfate salts is an efficacious and well tolerated regimen. Obesity and a longer time interval between the end of the second dose and colonoscopy initiation negatively influence bowel cleanliness. [ABSTRACT FROM AUTHOR]

The Sample Analysis at Mars-Evolved Gas Analyzer (SAM-EGA) on the Curiosity rover detected hydrogen chloride (HCl) and sulfur dioxide (SO2) gas evolutions above 600 °C and 700 °C, respectively, from several drilled rock and soil samples collected in Gale crater, which have been attributed to NaCl and Mg sulfates. Although NaCl and Mg sulfates do not evolve HCl or SO2 within the SAM temperature range (<~870 °C) when analyzed individually, they may evolve these gases at <870 °C and become detectable by SAM-EGA when mixed. This work aims to determine how Mg sulfate and NaCl interact during heating and how that affects evolved HCl and SO2 detection temperatures in SAM-EGA. Solid mixtures of NaCl and kieserite were analyzed using a thermogravimeter/differential scanning calorimeter furnace connected to a quadrupole mass spectrometer, configured to operate under similar conditions as SAM, and using X-ray diffraction of heated powders. NaCl analyzed individually did not evolve HCl; however, NaCl/kieserite mixtures evolved HCl releases with peaks above 600 °C. The results suggested that kieserite influenced HCl production from NaCl via two mechanisms: (1) kieserite depressed the melting point of NaCl, making it more reactive with evolved water; and (2) SO2 from kieserite decomposition reacted with NaCl and water (i.e., Hargreaves reaction). Additionally, NaCl catalyzed the thermal decomposition of kieserite, such that the evolved SO2 was within the SAM-EGA temperature range. The results demonstrated that SAM-EGA can detect chlorides and Mg sulfates when mixed due to interactions during heating. These phases can provide information on past climate and mineral formation conditions. [ABSTRACT FROM AUTHOR]

Thermal behavior of vergasovaite, ideally Cu3O(SO4)(MoO4), and its synthetic analog has been studied by high-temperature single-crystal X-ray diffraction in the temperature range of 300–1100 K. According to EMPA results, the empirical formulas are (Cu2.36Zn0.61)Σ2.97O[(Mo0.91S0.08V0.04)Σ1.03O4](SO4) for vergasovaite and Cu2.97O[(Mo0.92S0.09)Σ1.01O4](SO4) for its synthetic analog. The mineral is stable up to 950 ± 15 K; at 975 K, the unit-cell parameters and volume increase abruptly due to topotactic transformation of vergasovaite to cupromolybdite, Cu3O(MoO4)2. The transformation is accompanied by loss of sulfur (and excess copper) without destruction of the crystal. The thermal expansion of the vergasovaite structure is strongly anisotropic, being minimal along the [O2Cu6]8+ chains comprised of vertex-sharing OCu4 tetrahedra. This peculiar thermal behavior can be explained by the anisotropy of bond-length evolution in the Cu1O6 and Cu3O6 octahedra and the flexibility of the S-O-Cu and Mo-O-Cu bond angles. Synthetic Zn- and V-free analogs demonstrate negative thermal expansion at 425–625 K and melt at as low temperature as 700 K with no indication of transformation or recrystallization at least below 1200 K. The topotactic transformation observed in vergasovaite may have important implications for the design of novel materials and for understanding the alteration processes of copper minerals. [ABSTRACT FROM AUTHOR]

• Fe/Mg phyllosilicates and mono- and polyhydrated Mg sulfates are detected in Mikumi crater. • Possible desiccation/hydraulic fracturing on crater floor. • Phyllosilicates are on top of the sulfate units, meaning that they formed later than sulfates. • Mikumi crater is a key area in Meridiani Planum to investigate Mars' ancient climate. The region of Meridiani Planum on Mars retains the evidence of multiple surface and near-surface aqueous processes that span from the Noachian to the Hesperian. This makes it an interesting spot for better understanding the characteristics and the evolution of Mars' aqueous environment between these two fundamental epochs. Here we investigate the mineralogy, stratigraphy, and morphology of the Noachian–Hesperian sedimentary materials that fill a 16-km-wide crater named Mikumi, located in the northern part of Meridiani Planum. The analysis was carried out combining observations from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), the High Resolution Imaging Science Experiment (HiRISE), and the Context Imager (CTX). About 20–30 meters, on average, of Fe/Mg phyllosilicate-rich rocks and a thick sequence (75 m) of both mono- and polyhydrated Mg sulfates are detected on the crater floor. Both layers postdate the impact event. Most of the hydrated terrains are extensively polygonally fractured, suggesting the possible action of water-related processes such as desiccation and hydro fracturing on the sediments. Stratigraphic analysis clearly shows that Fe/Mg phyllosilicates were deposited on top of the sulfate sequence, meaning that they are younger than sulfates. This can have interesting implications on paleoclimatic studies of Mars as it shows that a simple timeline going from a clay-rich Noachian to a sulfate-rich Hesperian oversimplifies the evolution of Mars' mineralogy and related aqueous environment at the Noachian–Hesperian boundary. [ABSTRACT FROM AUTHOR]

We recently showed that 6-sulfo sialyl N-acetyllactosamine (LacNAc) in O-linked glycans recognized by the CL40 antibody is abundant in the pleural mesothelium under physiological conditions and that these glycans undergo complementary synthesis by GlcNAc6ST2 (encoded by Chst4) and GlcNAc6ST3 (encoded by Chst5) in mice. GlcNAc6ST3 is essential for the synthesis of R-10G-positive keratan sulfate (KS) in the brain. The predicted minimum epitope of the R-10G antibody is a dimeric asialo 6-sulfo LacNAc. Whether R-10G-reactive KS/sulfated LacNAc oligosaccharides are also present in the pleural mesothelium was unknown. The question of which GlcNAc6STs are responsible for R-10G-reactive glycans was an additional issue to be clarified. Here, we show that R-10G-reactive glycans are as abundant in the pulmonary pleura as CL40-reactive glycans and that GlcNAc6ST3 is only partially involved in the synthesis of these pleural R-10G glycans, unlike in the adult brain. Unexpectedly, GlcNAc6ST2 is essential for the synthesis of R-10G-positive KS/sulfated LacNAc oligosaccharides in the lung pleura. The type of GlcNAc6ST and the magnitude of its contribution to KS glycan synthesis varied among tissues in vivo. We show that GlcNAc6ST2 is required and sufficient for R-10G-reactive KS synthesis in the lung pleura. Interestingly, R-10G immunoreactivity in KSGal6ST (encoded by Chst1) and C6ST1 (encoded by Chst3) double-deficient mouse lungs was markedly increased. MUC16, a mucin molecule, was shown to be a candidate carrier protein for pleural R-10G-reactive glycans. These results suggest that R-10G-reactive KS/sulfated LacNAc oligosaccharides may play a role in mesothelial cell proliferation and differentiation. Further elucidation of the functions of sulfated glycans synthesized by GlcNAc6ST2 and GlcNAc6ST3, such as R-10G and CL40 glycans, in pathological conditions may lead to a better understanding of the underlying mechanisms of the physiopathology of the lung mesothelium. [ABSTRACT FROM AUTHOR]

The common approach to creating antimicrobial polymer materials is the distribution of a bactericidal additive in a material by mixing the additive with a solution or a melt of the polymer. This work proposes the method introducing of copper(II) sulfate, which has antimicrobial properties, into a poly(lactic acid) film by forced impregnation of a salt solution via the crazing mechanism. CuSO4 has been found to be uniformly distributed in the bulk of the polymer in the form of particles with sizes of about 100 nm. In the course of the structural modification, the surface of the polymer film becomes rougher and more hydrophobic. The water contact angle increases from 40° to 60°–65°. The incorporation of CuSO4 does not affect the surface properties but has a reinforcing effect on the polymer matrix as is evident from tensile tests (strength and elongation at break increase by 2.5 and 1.4 times, respectively). [ABSTRACT FROM AUTHOR]

New biamphiphilic surfactants (BSs) have been synthesized based on alkylmethylmorpholinium cation and dodecyl sulfate anion (Mor-n(DS), n = 4, 6, 8, 10). The structure of the biamphiphiles has been characterized by IR spectroscopy, 1H NMR spectroscopy, mass spectrometry, and elemental analysis. The aggregation behavior of the biamphiphiles in aqueous solutions has been assessed by tensiometry, conductometry, fluorescence spectroscopy (using a pyrene probe) and dynamic and electrophoretic light scattering. It has been shown that an increase in the hydrophobic tail length by two carbon atoms in an amphiphilic cation leads to an increase in the surface activity of the surfactant by ~5 units and a decrease in the aggregation threshold of the systems by 1.5–2 times. It has been established that the formation of aggregates with hydrodynamic diameters of 20–120 nm depending on the alkyl chain length of the alkylmethylmorpholinium cation and BS concentration. The zeta potential of the systems ranges from –25 to –100 mV and decreases with increasing biamphiphile concentration. Spectrophotometry has been employed to show a significant solubilization capacity of the biamphiphiles with respect to a hydrophobic dye Orange OT. The compounds obtained may be of interest for biomedical applications and other high-tech areas. [ABSTRACT FROM AUTHOR]

Galvanic interactions present alternative strategies to achieve a more efficient Cu dissolution from CuFeS2. The present work studied the interaction between chalcopyrite–magnetite (CuFeS2-Fe3O4) in acidified ferric sulphate Fe2(SO4)3-H2SO4 at a solution pH of 1.8 and a temperature of 25 or 50 °C. The addition of Fe3O4 to CuFeS2 forms a galvanic couple, which positively impacts the dissolution of Cu. The results showed that the presence of Fe3O4 led to high and fast Cu dissolution rates and decreased significantly the activation energy, from 83 to 57 kJ/mol. In addition to that, the solid residues revealed that CuFeS2 dissolution produced intermediate Cu-S-rich phases: CuS, Cu2S and Cu5FeS4, which appeared to envelop CuFeS2, had no observable intermediate phase while in the presence of Fe3O4. The results showed that 94% of Cu could be recovered after 5 h of leaching at 50 °C at a Fe3O4/CuFeS2 ratio of 4:1 and a 460 mV Ag/AgCl solution potential. The findings of this study present an option for efficient Cu dissolution from CuFeS2 in ferric sulphate at atmospheric pressure. [ABSTRACT FROM AUTHOR]

The expansion induced by sulfate attack on cement-treated aggregates (SACA) is a well-known problem that can be solved. It causes obvious heaves in road bases and railway subgrades. In this paper, the effects of the sodium sulfate content, cement content, degree of compaction, sulfate types, attack types, aluminum ion supply, concentration of curing sulfate solution, and temperature on the expansion behavior induced by SACA were investigated over 60 days in the laboratory. Based on the Sobol sensitivity analysis method, the influence of the sensitivity of each factor on the expansion was quantitatively analyzed, and the dominant factor of expansion was proposed. Results show that sulfate content is the domain factor of expansion that is induced by SACA, and it presents a logarithmic function relationship with strain. The 0.5% sodium sulfate content is the minimum sulfate content which causes the expansion that is induced by SACA. When the sulfate content is less than 1%, the expansion induced by SACA is minor. When the sulfate content is between 1% and 3%, the expansion behavior is expressed in four stages as follows: rapid strain increase, followed by a short stagnation period, then a significant strain increase and, finally, constant strain. When the sulfate content is greater than 5%, there are two stages comprising the expansion behavior as follows: the rapid strain increases and constant strain occurs. Greater sulfate content, greater degree of compaction, and lower temperature have positive effects on the expansion induced by SACA. The cement content does not have a consistent effect on expansion behavior. Compared with a sodium sulfate attack, both the reaction rate and expansion of cement-treated aggregates that are attacked by gypsum are smaller, and the attack period is also longer. When the sulfate content is greater than 1%, the addition of kaolin promotes the progression of the expansion induced by SACA. A small amount of water is sufficient for the demand for the sulfate attack. When the sulfate content is at a certain level, the expansion induced by SACA that is under external attack is much smaller than the expansion that is under internal attack. This study is expected to serve as a reference for future research on the mechanics of SACA, and it attempts to provide theoretical support for amending expansions that are induced by SACA. [ABSTRACT FROM AUTHOR]

Sulfate-rich sedimentary rocks explored by the Opportunity rover during its 14-year surface mission at Meridiani Planum provide an invaluable window into the thousands of sulfate deposits detected on Mars via remote sensing. Existing models explaining the formation of martian sulfates can be generally described as either bottom-up, groundwater-driven playa settings or top-down icy chemical weathering environments. Here, we propose a hybrid model involving both bottom-up and top-down processes driven by freeze-thaw cycles. Freezing leads to cryo-concentration of acidic fluids from precipitations at the surface, facilitating rapid chemical weathering despite low temperatures. Cryosuction causes the upward migration of vadose water and even groundwater with dissolved ions, resulting in the accumulation of ions in near-surface environments. Evaporation precipitates salts, but leaching separates chlorides from sulfates during the thawing period. Freeze-thaw cycles, therefore, can enrich sulfates at the surface. While freeze-thaw is more commonly understood as a mechanism of physical weathering, we suggest that it is a fundamental aspect of chemical weathering on Mars. [ABSTRACT FROM AUTHOR]

In this work, the authors present as an innovation, the homogeneous sulfonation of Udel® polysulfone (PSU) with acetylsulfate (ACS) under reflux at 45°C in dichloromethane and inert N2 atmosphere (g) for 1.5 h. Different proportions of ACS were used, obtaining sulfonated products with varying degrees of sulfonation (DS). Confirmation of sulfonated polysulfone (PSU-S), denominated as PSU-SA (high degree of sulfonation) and PSU-SB (low degree of sulfonation), was carried out by FTIR and ¹H NMR. Determination of DS was carried out through thermogravimetric analysis (TGA/DSC), varying indexes between 0.883 and 3.022, which correspond to a sulfonated polymer with ion exchange capacity (IEC) from 1.720 to 4.400 meq/g. The evolution of DS related to methods used was monitored and confirmed by ¹H NRM. Sulfonation is undertaken to enhance the suitability of this polymer for future applications in the production of biofuels, targeting its utilization in catalytic processes for esterification and transesterification mechanisms of oils and fats. [ABSTRACT FROM AUTHOR]

Densities of aqueous solutions of MnSO 4 , CoSO 4 , NiSO 4 and CuSO 4 have been measured by vibrating tube densimetry up to near-saturation concentrations over the temperature range 293.15 ≤ T / K ≤ 343.15 at 5 K intervals and at 0.1 MPa pressure. Apparent molar volumes, V ϕ , calculated from the densities revealed close similarities among all four electrolytes, with their V ϕ values essentially differing by constant concentration-independent addends for each salt at each temperature. It was found that there is an almost linear relationship between V ϕ (MSO 4 ,aq) and the M–O bond length of the hydrated cations obtained from structural studies. This relationship can be used to predict values of V ϕ (MSO 4 ,aq) for other sulfate salts over wide ranges of concentration and temperature, providing that the requisite structural data are available. Measurements of selected ternary, quaternary and quinary mixtures of these electrolytes at constant total concentrations showed that their V ϕ values almost always exhibit linear mixing (Young's rule) behavior at all temperatures investigated. This finding can be exploited to predict the volumetric properties of solutions containing complex mixtures of bivalent metal sulfates. [ABSTRACT FROM AUTHOR]

The study aims to analyze three aspects. (1) Formulation of biochar from wood refinery sawmill waste at pyrolysis temperatures of 450°C and 550°C with pyrolysis times of 2 and 4 hours. (2) The best wood refinery sawing waste biochar dosage to improve the chemical quality of acidic sulfate soil through improving soil pH, Al-dd, N, P, and K of the soil. (3) Growth and production of paddy on acidic sulfate soils by application of ameliorant biochar of waste sawmill wood mill. The research was conducted in acidic sulfate soil in a screen house in the Experimental Garden of the Faculty of Agriculture, Syiah Kuala University. Soil samples and biochar were analyzed at the Soil and Plant Research Laboratory of the Faculty of Agriculture. The study was an experiment using a factorial complete randomized design with two factors: the temperature and pyrolysis time and the dose of biochar. The results showed that the application of biochar waste from sawmill wood refineries had a very significant and significant effect on improving the quality of acidic sulfate soil and the growth and production of rice fields. The formulation of biochar at a pyrolysis temperature of 550°C for 2-hour pyrolysis with 20 tons/ha is the best improvement in acid sulfate soil quality, growth, and rice field production. [ABSTRACT FROM AUTHOR]

Recent research on atmospheric particle formation has shown substantial discrepancies between observed and modeled atmospheric sulfate levels. This is because models mostly consider sulfate originating from S O 2 oxidation by •OH radicals in mechanisms catalyzed by solar radiation while ignoring other pathways of non-radical S O 2 oxidation that would substantially alter atmospheric sulfate levels. Herein, we use high-level quantum chemical calculations based on density functional theory and coupled cluster theory to show that monoethanolamine (MEA), a typical alkanolamine pollutant released from C O 2 capture technology, can facilitate the conversion of atmospheric S O 2 to sulfate in a non – •OH – radical oxidation mechanism. The initial process is the MEA-induced S O 2 hydrolysis leading to the formation of H O S O 2 − • M E A H + . The latter entity is thereafter oxidized by ozone ( O 3 ) and nitrogen dioxide ( N O 2 ) to form H S O 4 − • M E A H + , which is an identified stabilizing entity in sulfate-based aerosol formation. Results show that the H O S O 2 − • M E A H + reaction with O 3 is kinetically and thermodynamically more feasible than the reaction with N O 2 . The presence of an additional water molecule further promotes the H O S O 2 − • M E A H + reaction with O 3 , which occurs in a barrierless process, while it instead favors HONO formation in the reaction with N O 2 . The investigated pathway highlights the potential role alkanolamines may play in S O 2 oxidation to sulfate, especially under conditions that are not favorable for •OH production, thereby providing an alternative sulfate source for aerosol modeling. The studied mechanism is not only relevant to sulfate formation and may effectively compete with reactions with sulfur dioxide and hydroxyl radicals under heavily polluted and highly humid conditions such as haze events, but also an important pathway in MEA removal processes. [ABSTRACT FROM AUTHOR]

To explore the deformation behavior and failure strength of sulfate saline silty clay at a temperature of -10℃ and confining pressures of 6~10 MPa, we have performed low-temperature triaxial shear tests on sulfate saline silty clay in Hexi region of Gansu province, China. The variation trend of deviatoric stress, volumetric strain and initial deformation modulus with confining pressure were analyzed. The results demonstrated that the stress-strain curve of frozen sulfate saline silty clay was hyperbolic and the deviatoric stress increased as the axial strain increased and was eventually constant. Owing to particle breakage and melting of ice, when the confining pressure, σ3>6 the strength decreased as the confining pressure increased and the sample exhibited volumetric shrinkage throughout the entire confining-pressure range. A constitutive model of frozen sulfate saline silty clay under high confining pressure has been proposed in combination with the Duncan Chang model and the validity of the model has been confirmed by comparison with test data. [ABSTRACT FROM AUTHOR]

The use of byproducts as supplementary cementitious materials (SCMs) and recycled coarse aggregates (RCAs) can contribute to the production of more sustainable self-compacting concrete (SCC) while modifying the durability properties of these mixtures. Thus, this study addresses the combined use of concrete waste (CW) as RCA and residue of masonry (RM) as SCM, the CW and RM obtained from construction and demolition waste, to generate SCC mixtures and to evaluate the performance of these mixtures under sulfate attack (5% Na2SO4 and 5% MgSO4 solutions). In detail, a reference SCC (M1) and three SCCs with 25% of RM and different level RCAs (0%, 50%, and 100% replacement by volume) were cast. The hardened properties of the SCC mixtures were assessed in terms of compressive strength and sulfate attack. The results showed that the SCC mixtures with RM and RCA, cured in water, exhibited lower compressive strength results in all the evaluated ages compared with M1 (reference mixture, without RM and RCA). However, the SCC mixture with RM presented the maximum compression strength result among the different mixtures at 180 and 360 days. When mixtures were exposed to sulfate solutions, the SCC mixture with RM showed the best performance, and even the SCC mixtures with RM and RCA exhibited lower linear expansion and loss of compressive strength when compared with M1. The presence and severity of the sulfate attack were assessed via X-ray diffraction and scanning electron micrograph, which confirmed the presence of ettringite and gypsum in all the exposed SCC mixtures in the Na2SO4 and MgSO4 solutions. [ABSTRACT FROM AUTHOR]

Sm2(SO4)3(H2O)5, monoclinic, C2/c (no. 15), a = 15.653(3) Å, b = 9.5369(19) Å, c = 10.199(2) Å, β = 120.36(3)°, V = 1313.9(6) Å3, Z = 1, Rgt(F) = 0.0281, wRref(F2) = 0.0664, T = 293 K. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative joint condition with limited disease-modifying treatments currently. Palm tocotrienol-rich fraction (TRF) has been previously shown to be effective against OA, but its mechanism of action remains elusive. This study aims to compare serum metabolomic alteration in Sprague–Dawley rats with monosodium iodoacetate (MIA)-induced OA which were treated with palm TRF, glucosamine sulphate, or a combination of both. This study was performed on thirty adult male rats, which were divided into normal control (n = 6) and OA groups (n = 24). The OA group received intra-articular injections of MIA and daily oral treatments of refined olive oil (vehicle, n = 6), palm TRF (100 mg/kg, n = 6), glucosamine sulphate (250 mg/kg, n = 6), or a combination of TRF and glucosamine (n = 6) for four weeks. Serum was collected at the study's conclusion for metabolomic analysis. The findings revealed that MIA-induced OA influences amino acid metabolism, leading to changes in metabolites associated with the biosynthesis of phenylalanine, tyrosine and tryptophan as well as alterations in the metabolism of phenylalanine, tryptophan, arginine and proline. Supplementation with glucosamine sulphate, TRF, or both effectively reversed these metabolic changes induced by OA. The amelioration of metabolic effects induced by OA is linked to the therapeutic effects of TRF and glucosamine. However, it remains unclear whether these effects are direct or indirect in nature. [ABSTRACT FROM AUTHOR]

PM2.5 pollution over Hangzhou Bay area, China has received continuous attention. In this study, PM2.5 samples were collected simultaneously in six typical cities in Zhejiang Province from 15 October 2019 to 15 January 2020 (autumn and winter) and from 1 June to 31 August 2020 (summer), and major water-soluble ions were analyzed. Average concentrations of NO3− and SO42− in the six cities were 3.93–15.64 μg/m3 and 4.61–7.58 μg/m3 in autumn and winter, with mass fractions of NO3− and SO42− in PM2.5 up to 19.6–34.2% and 13.6–26.3%, respectively, while in summer, they were 1.23–2.64 μg/m3 and 2.22–4.14 μg/m3, with mass fractions of 7.0–15.0% and 14.7~25.1%. Both NO3− and SO42− were mostly from gas-to-particle transformation of precursors. High relative humidity in the six cities was suggested to significantly promote the formation of NO3− and SO42−, particularly in autumn and winter, while enhanced atmospheric oxidation favored the formation of SO42− in summer. However, the formation of NO3− was inhibited under a high temperature of >15 °C. The concentrations of SO42− and NO3 were mostly correlated with each other among the six cities. Potential source contribution function analysis indicated that both SO42− and NO3− were mostly from local pollution of Hangzhou Bay area in Zhejiang Province and also transported from Shanghai and the southern region of Jiangsu Province. This study contributed to the understanding of regional characteristics of SO42− and NO3− in Hangzhou Bay area and suggested that joint prevention and control efforts should be strengthened to reduce regional PM2.5 pollution. [ABSTRACT FROM AUTHOR]

Sodium tanshinone IIA sulphate (STS) is a product originated from Salvia miltiorrhiza Bunge [Lamiaceae], which exerts an antitumour effect. However, the role of STS on lung adenocarcinoma (LUAD) remains unexplored. Our study explores the effect and mechanism of STS against LUAD. LUAD cells were treated with 100 μM STS for 24 h and control group cells were cultured under normal medium conditions. Functionally, the viability, migration, invasion and angiogenesis of LUAD cells were examined by MTT, wound healing, transwell and tube formation assay, respectively. Moreover, cells were transvected with different transfection plasmids. Dual luciferase reporter and RNA immunoprecipitation (RIP) assays were used to verify the relationship between miR-874 and eEF-2K. STS significantly decreased the viability (40–50% reduction), migration (migration rate of A549 cells from 0.67 to 0.28, H1299 cells from 0.71 to 0.41), invasion (invasion numbers of A549 cells from 172 to 55, H1299 cells from 188 to 35) and angiogenesis (80-90% reduction) of LUAD cells. Downregulation of miR-874 partially abolished the antitumour effect of STS. EEF-2K was identified to be the target of miR-874, and its downregulation markedly abolished the effects of miR-874 downregulation on tumourigenesis of LUAD. Moreover, silencing of TG2 abrogated eEF-2K-induced progression of LUAD. STS attenuated the tumourigenesis of LUAD through the mediation of the miR-874/eEF-2K/TG2 axis. STS is a promising drug to fight against lung cancer, which might effectively reverse drug resistance when combined with classical anticancer drugs. [ABSTRACT FROM AUTHOR]

Aims: Indoxyl sulfate and parathyroid hormone (PTH), which accumulate in chronic kidney disease (CKD), have been reported to reduce cytochrome P450(CYP)3A activity. Homozygotes of the CYP3A5*3 allele have reduced CYP3A5 activity compared to carriers of at least one CYP3A5*1 allele. 4β‐Hydroxycholesterol (4β‐OHC) has been established as an endogenous substrate reflecting CYP3A activity. 4β‐OHC is produced through hydroxylation by CYP3A4 and CYP3A5 and by autoxidation of cholesterol, whereas 4α‐hydroxycholesterol (4α‐OHC) is produced solely by autoxidation of cholesterol. This study focused on CKD patients and evaluated the effects of plasma indoxyl sulfate and intact‐PTH concentrations on plasma 4β‐OHC concentration, 4β‐OHC/total cholesterol ratio and 4β‐OHC–4α‐OHC, with consideration of the influence of CYP3A5 polymorphism. Methods: Sixty‐three CKD patients were analysed and divided into CYP3A5 carrier group (n = 26) and non‐carrier group (n = 37). Results: Plasma indoxyl sulfate significantly correlated inversely with 4β‐OHC concentration and with 4β‐OHC–4α‐OHC in both the CYP3A5*1 carrier group (r = −0.42, P =.034; r = −0.39, P =.050, respectively) and the non‐carrier group (r = −0.45, P =.0054; r = −0.39, P =.019, respectively). However, multiple regression analysis did not identify plasma indoxyl sulfate concentration as a significant independent factor associated with any of the CYP3A activity indices. There was no significant correlation between plasma intact‐PTH concentration and any of the CYP3A activity indices. Conclusions: The present results suggest that plasma indoxyl sulfate and intact‐PTH concentrations do not have clinically significant effects on CYP3A activity in patients with CKD. [ABSTRACT FROM AUTHOR]

The novel alkali-activated filling grout (AAG) for shield tunnels requires detailed understanding of its sulfate resistance prior to practical application. This paper presents a comparative study of the sulfate resistance of a typical ordinary portland cement (OPC)-based grout and two groups of representative AAG formulated with industrial by-products including fly ash, ground granulated blast-furnace slag, and steel slag as the solid precursors. In the study, the grout samples after 28 days of standard curing were exposed to the 5% by weight Na2SO4 (pH = 7.92) and 5% by weight MgSO4 (pH = 7.25) solutions, respectively, to simulate different cases of external sulfate erosion. The sulfate resistance and deterioration mechanism of various grout samples were evaluated and analyzed via multitechnical examinations including visual appearance, mass loss, compressive/flexural strength, strength retention coefficient, mineral composition, microstructure morphology, and pore-size distribution at different test ages. The experimental results indicated that whether under Na2SO4 or MgSO4 erosion, AAG always exhibited more slight deterioration than the OPC-based grout in terms of visual appearance, mass loss, and strength reduction. The reasons for these observations are as follows. The main gel products of AAG were mainly C-(A)-S-H and N-A-S-H, which interweaved and coexisted to form a denser matrix structure than that of the OPC-based grout. The resulting poorer permeability of the AAG matrix was not conducive to the ion exchange between the matrix and the environmental solution. In addition, compared with the OPC-based grout, the lower calcium content and more stable bonded aluminum phases in AGG limited the formation of expansive products responsible for microcracking under sulfate erosion. MgSO4 could cause more severe deterioration than Na2SO4 , mainly due to the promotion of decalcification of calcium-containing phases by the presence of Mg2+ and the resulting gel products harmful to the matrix. This study demonstrated the excellent sulfate resistance of AAG, which can provide scientific basis for its future engineering application. [ABSTRACT FROM AUTHOR]

Recently, steel fiber–reinforced magnesium phosphate cement–based concrete (SFRMPCC) has attracted much attention due to its excellent properties. To apply this new type of concrete to practical engineering, this paper evaluates the effect of steel fiber (SF) content and curing age on the water and sulfate resistance of magnesium phosphate cement–based concrete (MPCC). Specimens containing fly ash and metakaolin and with different SF volume contents were prepared and subjected to curing in air, water, and 5% Na2SO4 solution. The mass change, cubic compressive strength (CCS), strength retention rate, deterioration factor, microstructure, and phase composition were analyzed. Empirical formulas for strength prediction are proposed using range, variance, and nonlinear regression analysis methods. The results showed that the specimens immersed in water and Na2SO4 solution had good mass retention. The compressive strength of air-cured specimens gradually increased with the curing age, and the addition of a proper amount of SF could improve the strength under air curing. However, the addition of SF had a negative effect on the compactness and strength of specimens immersed in water and sulfate solution. SFRMPCC and MPCC had good resistance to sulfate attack, which may be related to the new reaction in the magnesium phosphate cement (MPC) matrix. [ABSTRACT FROM AUTHOR]

Plasmid DNA (pDNA) is a key biotechnological product whose importance became apparent in the last years due to its role as a raw material in the messenger ribonucleic acid (mRNA) vaccine manufacturing process. In pharmaceutical production processes, cells need to grow in the defined medium in order to guarantee the highest standards of quality and repeatability. However, often these requirements result in low product titer, productivity, and yield. In this study, we used constraint-based metabolic modeling to optimize the average volumetric productivity of pDNA production in a fed-batch process. We identified a set of 13 nutrients in the growth medium that are essential for cell growth but not for pDNA replication. When these nutrients are depleted in the medium, cell growth is stalled and pDNA production is increased, raising the specific and volumetric yield and productivity. To exploit this effect we designed a three-stage process (1. batch, 2. fed-batch with cell growth, 3. fed-batch without cell growth). The transition between stage 2 and 3 is induced by sulfate starvation. Its onset can be easily controlled via the initial concentration of sulfate in the medium. We validated the decoupling behavior of sulfate and assessed pDNA quality attributes (supercoiled pDNA content) in E. coli with lab-scale bioreactor cultivations. The results showed an increase in supercoiled pDNA to biomass yield by 33% and an increase of supercoiled pDNA volumetric productivity by 13 % upon limitation of sulfate. In conclusion, even for routinely manufactured biotechnological products such as pDNA, simple changes in the growth medium can significantly improve the yield and quality. Highlights: Genome-scale metabolic models predict growth decoupling strategies. Sulfate limitation decouples cell growth from pDNA production. Sulfate limitation increases the specific supercoiled pDNA yield by 33% and the volumetric productivity by 13%. We propose that sulfate limitation improves the biosynthesis of over 25% of naturally secreted products in E. coli. [ABSTRACT FROM AUTHOR]

This study investigates the performance of recycled aggregate concrete incorporating different sizes and concentrations of coarse aggregate under sodium sulphate and normal water curing. Ten mixes were produced, having two control mixes of 12 to 20 mm and 5 to 12 mm coarse aggregate size. The rest of the mixes have supplementary cementitious material with 0%, 15%, 30%, and 45% substitution of respective sizes normal aggregate by recycled aggregate. The fresh recycled aggregate concrete mixes were assessed through the slump, ball penetration, and compacting factor test, which exhibited a falling trend with the percentage increase of recycled aggregate. Moreover, compressive strength and ultrasonic pulse velocity drop with the percentage of RCA increases at 7, 28, and 91-days normal curing and 5% Na2SO4 solution curing at 91 days. The compressive strength and ultrasonic pulse velocity of 5-12 mm coarse aggregate concrete showed improvement over 12-20 mm coarse aggregate concrete of the same replacement for both curing. However, 5% Na2SO4 solution curing specimens exhibit around 5-11% decrease in compressive strength and higher penetration depth than normal curing . Furthermore, the outer face of the silica fume included samples have received fewer white patches after sodium sulphate immersion. [ABSTRACT FROM AUTHOR]

In this paper, firstly, the effects of graphene oxide on the mechanical properties of concrete were investigated. Secondly, the degradation and mechanism of the mechanical properties of graphene oxide concrete (GOC) under sulfate attack and a freeze–thaw environment were investigated. In addition, the dynamic modulus of elasticity (MOEdy) and uniaxial compressive strength (UCS) of the GOC were measured under different environmental conditions. According to the test results, the incorporation of graphene oxide in appropriate admixtures could improve the mechanical properties of concrete in these two working environments. It is worth noting that this effect is most pronounced when 0.05 wt% graphene oxide is incorporated. In the sulfate attack environment, the MOEdy and UTS of the GOC0.05% specimen at 120 cycles decreased by 22.28% and 24.23%, respectively, compared with the normal concrete specimens. In the freeze–thaw environment, the MOEdy and UTS of the GOC0.05% specimen at 90 cycles decreased by 13.96% and 7.58%, respectively, compared with the normal concrete specimens. The scanning electron microscope (SEM) analysis showed that graphene oxide could adjust the aggregation state of cement hydration products and its own reaction with some cement hydration crystals to form strong covalent bonds, thereby improving and enhancing the microstructure density. [ABSTRACT FROM AUTHOR]

External sulfate attack is a remarkable and complex phenomenon of degradation of cement matrixes. This paper proposes a method to calculate sulfate diffusion coefficients based on ion migration testing, in order to establish parameters for concrete service life prediction models based on a fast test. The influence of the type (sodium and magnesium) and concentration (5% and 10% SO42−) of the sulfate solution for a concrete matrix was evaluated in the tests. Sulfate concentrations were monitored by measuring the electrical conductivity of the anode compartment. The results were validated by comparing them with those obtained in natural diffusion tests. Similar sulfate profiles were obtained for concrete samples after 1 month of migration and after 3 and 6 months of diffusion, mainly for magnesium sulfate. The greatest correlations between the calculated diffusion coefficients were achieved at higher concentrations of SO42− in the cathode compartment. The results indicated that the proposed migration method enables the calculation of the sulfate diffusion coefficients in concrete. [ABSTRACT FROM AUTHOR]

Neuronal Kv7 voltage-gated potassium channels generate the M-current and regulate neuronal excitability. Here, we report that dehydroepiandrosterone sulfate (DHEAS) is an endogenous Kv7 channel modulator that attenuates Gq-coupled receptor-induced M-current suppression. DHEAS reduced muscarinic agonist-induced Kv7-current suppression of Kv7.1, Kv7.2, Kv7.4, or Kv7.5 homomeric currents and endogenous M-currents in rat sympathetic ganglion neurons. However, DHEAS per se did not alter the voltage dependence of these Kv7 homomeric channels or the m1 receptor-induced activation of phospholipase C or protein kinase C. DHEAS-treated Kv7.2 homomeric currents became resistant to depletion of phosphatidylinositol 4,5-bisphosphate (PIP2) induced by voltage-activated phosphatase, Ci-VSP or eVSP. Our computational models predicted a novel binding site for DHEAS in the cytoplasmic domain of Kv7 subunits. A single-point mutation of the predicted key histidine into cysteine in the rat Kv7.2 subunit, rKv7.2(H558C), resulted in a loss of effects of DHEAS on muscarinic Kv7 current sup-pression. Furthermore, in vivo administration of DHEAS in mice of both sexes reduced late phase pain responses in the formalin paw test. However, it did not have effects on early phase responses in the formalin paw test or responses in the hot plate test. Coadministration of a selective Kv7 inhibitor, XE991, and DHEAS eliminated analgesic effects of DHEAS in late phase responses in the formalin paw test. Collectively, these results suggest that DHEAS attenuates M-current suppression by stabilizing PIP2-Kv7 subunit interaction and can mitigate inflammatory pain. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) is a global health concern affecting millions worldwide. One of the critical challenges in CKD is the accumulation of uremic toxins such as p-cresol sulfate (pCS) and indoxyl sulfate (IS), which contribute to systemic damage and CKD progression. Understanding the transport mechanisms of these prominent toxins is essential for developing effective treatments. Here, we investigated whether pCS and IS are routed to the plasma membrane or to the cytosol by two key transporters, SLC22A11 and OAT1. To distinguish between cytosolic transport and plasma membrane insertion, we used a hyperosmolarity assay in which the accumulation of substrates into HEK-293 cells in isotonic and hypertonic buffers was measured in parallel using LC-MS/MS. Judging from the efficiency of transport (TE), pCS is a relevant substrate of SLC22A11 at 7.8 ± 1.4 µL min−1 mg protein−1 but not as good as estrone-3-sulfate; OAT1 translocates pCS less efficiently. The TE of SLC22A11 for IS was similar to pCS. For OAT1, however, IS is an excellent substrate. With OAT1 and p-aminohippuric acid, our study revealed an influence of transporter abundance on the outcomes of the hyperosmolarity assay; very high transport activity confounded results. SLC22A11 was found to insert both pCS and IS into the plasma membrane, whereas OAT1 conveys these toxins to the cytosol. These disparate transport mechanisms bear profound ramifications for toxicity. Membrane insertion might promote membrane damage and microvesicle release. Our results underscore the imperative for detailed structural inquiries into the translocation of small molecules. [ABSTRACT FROM AUTHOR]

The accumulation of authigenic carbonate in marine sediments has been regarded as a significant contributor to the carbon cycle over Earth's history. However, accurate quantification of the extent of authigenic carbonate formation in both modern and ancient oceans has been challenging due to limited approaches. Here, we analyzed calcium, magnesium, dissolved inorganic carbon, and alkalinity pore‐water profiles of 153 sites influenced by methane diffusion from the northern South China Sea. By combining these data with published data of diffusive sulfate flux, we found a significant positive correlation between carbonate precipitation rate and sulfate flux in the subseafloor. This correlation can be used to quantify the regional extent of authigenic carbonate formation, representing an advantage over a spatial interpolation approach. We therefore propose that the observed correlation can serve as a new approach for quantifying authigenic carbonate formation in shallow sediments along continental margins for both modern and ancient oceans. Plain Language Summary: Carbonate mineral precipitation through removing seawater dissolved inorganic carbon—the marine carbonate factory—plays a critical role in shaping marine carbon cycling and global climate. The formation of authigenic carbonate from pore‐water of marine sediments represents a variable share of the marine carbonate factory throughout geological history. However, it is challenging to quantify the extent of such authigenic carbonate formation. By analyzing pore‐water parameters from 153 sites influenced by methane diffusion of the northern South China Sea, we found a significant positive correlation between the rate of carbonate precipitation and the diffusive flux of sulfate into shallow sediments. Given the existence of estimates on the sizes of the seawater sulfate pool and diffusive fluxes of sulfate into sediments over Earth's history, we propose that the observed correlation can be used for quantifying authigenic carbonate formation in shallow sediments along continental margins through time, which will greatly advance our understanding for past carbon cycling and its relation to climate. Key Points: Porewater parameters from 153 sites of the northern South China Sea were evaluated to quantify the extent of authigenic carbonate formationRate of carbonate formation strongly correlates with diffusive flux of sulfate into sediments affected by methane diffusionA correlation of carbonate formation rate with sulfate flux is used to quantify most of authigenic carbonate formation in shallow sediments [ABSTRACT FROM AUTHOR]

This paper aims to assess the behavior of the unconfined compressive strength (UCS) of polypropylene fiber (PF) reinforced natural pozzolana-lime-stabilized expansive grey clayey soil (GS) contaminated by sulfates. Lime (0--8%), natural pozzolana (NP) (0--20%), and PF (0--3%) by dry weight of soil were used. GS was contaminated by different sulfate contents (0-6%) and UCS was assessed at various curing periods (7--120 days). Results showed that adding 8% lime alone or with 20% NP considerably improved UCS. Including 1% or 2% PF as reinforcement without sulfates in lime-stabilized GS transferred stress from GS to PF due to bonding. However, increasing PF beyond 2% formed lumps, reducing contact and friction coefficient, thus decreasing UCS. This means that the optimum PF dosage was found to be 2%. The UCS of GS increased with PF content up to 2% and then decreased. The UCS significantly increased with higher calcium sulfate content and curing period due to observed cementing agents in X-ray diffraction (XRD) and scanning electron microscopy (SEM). Adverse effect of ettringite mineral on UCS caused by sodium sulfate addition was suppressed with the combination of 20% NP and 2% PF in lime-stabilized GS. Binding forces from lime and NP resisted to ettringite expansion. Sensitivity of UCS to sulfate effect was more pronounced with sodium sulfate than calcium sulfate. In addition, NP--PF mixture in lime-stabilized GS was more effective, improving the strength of expansive soil, especially with sodium sulfate. In conclusion, reinforcement of NP-limestabilized expansive soils with PF is an effective method. [ABSTRACT FROM AUTHOR]

The use of lime in sulfate-bearing clayey soils has historically caused structural damage to infrastructures due to the formation of an expansive ettringite mineral. In this paper, a research was conducted to study the effectiveness of natural pozzolana (NP) for providing better stabilization of sulfate-bearing soils. Compaction and free-swell potential tests were first performed on lime-stabilized grey and red clayey soils (GS and RS) containing different contents of added sodium and calcium sulfates (2, 4 and 6% Na2SO4 or CaSO4⋅2H2O). Then, the same tests were repeated by adding 20%NP. The test results indicated that the presence of 4% and 6% Na2SO4 in the soil resulted in an abnormal increase in the swell potential of both lime-stabilized GS and RS. The X-ray diffraction (XRD) results confirmed the growth of the ettringite mineral responsible for this higher swell potential. However, the use of 8% lime with 20%NP in stabilizing sulfate-bearing clayey soils produced significant improvements in the optimum moisture content (OMC) and maximum dry density (MDD), as well as in the swell potential. The addition of 20%NP into the lime-stabilized GS and RS eliminated the harmful effect of Na2SO4. In addition, for 120-day curing period, the use of 6% CaSO4⋅2H2O was found very effective by reducing the swell potential of NP-lime-stabilized GS and RS from 7.33% to 0.4% and from 2.79% to 0.2%, respectively trips. [ABSTRACT FROM AUTHOR]

Sulfite oxidase is one of five molybdenum-containing enzymes known in eukaryotes where it catalyzes the oxidation of sulfite to sulfate. This review covers the history of sulfite oxidase research starting out with the early years of its discovery as a hepatic mitochondrial enzyme in vertebrates, leading to basic biochemical and structural properties that have inspired research for decades. A personal view on sulfite oxidase in plants, that sulfates are assimilated for their de novo synthesis of cysteine, is presented by Ralf Mendel with numerous unexpected findings and unique properties of this single-cofactor sulfite oxidase localized to peroxisomes. Guenter Schwarz connects his research to sulfite oxidase via its deficiency in humans, demonstrating its unique role amongst all molybdenum enzymes in humans. In essence, in both the plant and animal kingdoms, sulfite oxidase represents an important player in redox regulation, signaling and metabolism, thereby connecting sulfur and nitrogen metabolism in multiple ways. [ABSTRACT FROM AUTHOR]

Fecal microbiota transplantation (FMT) has emerged as a highly effective therapy for recurrent Clostridioides difficile infection (rCDI) and also a potential therapy for other diseases associated with dysbiotic gut microbiota. Monitoring metabolic changes in biofluids and excreta is a noninvasive approach to identify the biomarkers of microbial recolonization and to understand the metabolic influences of FMT on the host. In this study, the pre-FMT and post FMT urine samples from 11 rCDI patients were compared through metabolomic analyses for FMT-induced metabolic changes. The results showed that p-cresol sulfate in urine, a microbial metabolite of tyrosine, was rapidly elevated by FMT and much more responsive than other microbial metabolites of aromatic amino acids (AAAs). Because patients were treated with vancomycin prior to FMT, the influence of vancomycin on the microbial metabolism of AAAs was examined in a mouse feeding trial, in which the decreases in p-cresol sulfate, phenylacetylglycine, and indoxyl sulfate in urine were accompanied with significant increases in their AAA precursors in feces. The inhibitory effects of antibiotics and the recovering effects of FMT on the microbial metabolism of AAAs were further validated in a mouse model of FMT. Overall, urinary p-cresol sulfate may function as a sensitive and convenient therapeutic indicator on the effectiveness of antibiotics and FMT for the desired manipulation of gut microbiota in human patients. [ABSTRACT FROM AUTHOR]

Four salts, namely, 2,4,6‐triaminopyrimidinium 6‐chloronicotinate dihydrate, C4H8N5+·C6H3ClNO2−·2H2O, (I), 2,4,6‐triaminopyrimidinediium pyridine‐2,6‐dicarboxylate dihydrate, C4H9N52+·C7H3NO42−·2H2O, (II), 2,4,6‐triaminopyrimidinediium sulfate monohydrate, C4H9N52+·SO42−·H2O, (III), and 2,4,6‐triaminopyrimidinium 3,5‐dinitrobenzoate dihydrate, C4H8N5+·C7H3N2O6−·2H2O, (IV), were synthesized and characterized by X‐ray diffraction techniques. Proton transfer from the corresponding acid to the pyrimidine base has occurred in all four crystal structures. Of the four salts, two [(I) and (IV)] exist as monoprotonated bases and two [(II) and (III)] exist as diprotonated bases. In all four crystal structures, the acid interacts with the pyrimidine base through N—H...O hydrogen bonds, generating an R22(8) ring motif. The sulfate group mimics the role of the carboxylate anions. The water molecules present in compounds (I)–(IV) form water‐mediated large ring motifs. The formation of water‐mediated interactions in these crystal structures can be used as a model in the study of the hydration of nucleobases. Water molecules play an important role in building supramolecular structures. In addition to these strong hydrogen‐bonding interactions, some of the crystal structures are further enriched by aromatic π–π stacking interactions [(I) and (II)]. [ABSTRACT FROM AUTHOR]