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Three types of activators such as sodium hydroxide, calcium oxide and triethanolamine (TEA) are used to establish different activation environments to address the problems associated with the process of activating fly ash paste. We conducted mechanical tests and numerical simulations to understand the evolution of microstructure, and used environmental scanning electron microscopy (ESEM) and energy dispersive spectroscopy (EDS) techniques to analyze the microenvironments of the samples. The mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were investigated. The results revealed that under conditions of low NaOH content (1%–3%), the strength of the sample increased significantly. When the content exceeded 4%, the rate of increase in strength decreased. Based on the results, the optimal NaOH content was identified, which was about 4%. A good activation effect, especially for short-term activation (3–7 d), was achieved using TEA under high doping conditions. The activation effect was poor for long-term strength after 28 days. The CaO content did not significantly affect the degree of activation achieved. The maximum effect was exerted when the content of CaO was 2%. The virtual cement and concrete testing laboratory (VCCTL) was used to simulate the hydration process, and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)2 in the system. The activators also corroded the surface of the fly ash particles, resulting in a pozzolanic reaction. The active substances in fly ash were released efficiently, and hydration was realized. The pores were filled with hydration products, and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste. [ABSTRACT FROM AUTHOR]

The high acidity and low hydration activity of fluorgypsum restrict its application in the field of plastering gypsum. In order to solve this problem and promote the large-scale application of fluorgypsum in plastering gypsum, CaO and Ca(OH)2 were selected as neutralizer while Na2C2O4, Na2SO4, K2SO4, K2SiO3 and gypsum hemihydrate were selected as activator, to modify fluorgypsum. The effects of type and dosage of activator and neutralizer on modification effect were investigated. The results show that 3%(mass fraction) neutralizer can improve the pH value of fluorgypsum to around 9 and keep its free fluorine content around 0.02% (mass fraction). Considering the cost, the cheaper CaO is choose as neutralizer. In addition, K2SO4, Na2SO4 and gypsum hemihydrate as activator have good excitation effect, among which Na2SO4 has the best excitation effect. Plastering gypsum excited by 1.0% (mass fraction) Na2SO4 is prepared, with initial setting time of 119 min and final setting time of 252 min. Moreover, the compressive strength is 10.30 MPa while the flexural strength is 3.85 MPa. It should be noted that all indicators reach the requirements of "Plastering gypsum"(GB/T 28627-2023). [ABSTRACT FROM AUTHOR]

The development of solid waste-derived activators for the preparation of alkali-activated systems is of great significance for further enhancing the environmental friendliness and sustainability of alkali-activated materials. In this review, the potential feasibility of applying solid waste-derived activators to prepare alkali-activated systems is explored. Through a discussion of alkali-activation mechanisms, the effect of activators on high-calcium and low-calcium systems is highlighted first. The properties and limitations of commonly used industrial-grade alkali activators are reviewed next. Finally, recent reports on waste-derived activators in alkaline activation systems are summarized, revealing the advantages and development trends of solid wastes with CaO, K2O/Na2O, and SiO2 as the main components of effective substitutes for alkaline industrial exciters. [ABSTRACT FROM AUTHOR]

Peach varieties that differ in red coloration due to varied anthocyanin accumulation result from transcriptional regulation by PpMYB10s, a group of specific R2R3 MYBs. Here we investigated the mechanisms driving a lack of anthocyanin in yellow‐skinned 'Jinxiu' peach peel, as well as accumulation induced by UV irradiance. It was found that PpMYB10.1, PpMYB10.2 and PpMYB10.3 were positive regulators of anthocyanin accumulation, but the stimulation by PpMYB10.2 was weak. Low expression of PpMYB10.1 causes natural anthocyanin deficiency in 'Jinxiu' peel. However, the promoter sequences of PpMYB10.1 were identical in 'Jinxiu' and a naturally red‐coloured peach 'Hujingmilu'. Therefore, potential negative regulator(s) upstream of PpMYB10.1 were explored. A novel R2R3‐MYB repressor termed PpMYB80 was identified through comparative transcriptomic analysis and then functionally confirmed via transiently overexpressing and silencing in peach fruit, as well as transformation in tobacco. PpMYB80 directly binds to the promoter of PpMYB10.1 and inhibits its expression, but does not affect PpMYB10.3. In UV‐exposed 'Jinxiu' fruit, expression of PpMYB10.3 was upregulated, while PpMYB10.1 remained low and PpMYB80 enhanced, which results in accumulation of anthocyanin in peel. This study revealed a transcriptional cascade involving PpMYB activators and repressors in regulating basal and UV‐induced anthocyanin accumulation in peach peel. Summary Statement: To explore the mechanisms for natural deficient and UV‐induced anthocyanin accumulation in 'Jinxiu' peach peel, the study was conducted and it was revealed that anthocyanin accumulation is regulated by a transcriptional cascade involving activators PpMYB10.1/10.3 and repressor PpMYB80. [ABSTRACT FROM AUTHOR]

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Strong-alkali activation is a prerequisite needed to ensure the full polymerization activity of alkali slag binder and establish excellent mechanical properties; however, it substantially increases the preparation cost. In this study, the effects of both strong and weak alkaline activators on the activation performance of alkali slag were examined, using a combination of X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis methods. The reaction mechanism was analyzed under different alkaline conditions, and the preparation cost could be significantly reduced without significantly degrading mechanical properties. The results indicate that Ca(OH)2 can stimulate the reactivity of slag, resulting in a 40% decrease in compressive strength (compared to NaOH) but a 25–50% reduction in preparation cost. With increasing Ca(OH)2 dosage, the compressive strength first increases and then decreases. The best excitation effect is achieved at a dosage of 40 g Ca(OH)2 per 450 g GBFS. The formation of aluminosilicate is the main driving force for the observed increase in compressive strength. Excessive dosage of Ca(OH)2 will lead to its deposition in the specimen, thus affecting the development of compressive strength. [ABSTRACT FROM AUTHOR]

Copyright of Iron Steel Vanadium Titanium is the property of Iron Steel Vanadium Titanium Editorial Office 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.)

The phosphate‐starvation response transcription‐factor protein family is essential to plant response to low‐levels of phosphate. Proteins in this transcription factor (TF) family act by altering various gene expression levels, such as increasing levels of the acid phosphatase proteins which catalyze the conversion of inorganic phosphates to bio‐available compounds. There are few structural characterizations of proteins in this TF family, none of which address the potent TF activation domains. The phosphate‐starvation response‐like protein‐4 (PHL4) protein from this family has garnered interest due to the unusually high TF activation activity of the N‐terminal domain. Here, we demonstrate using solution nuclear magnetic resonance (NMR) measurements that the PHL4 N‐terminal activating TF effector domain is mainly an intrinsically disordered domain of over 200 residues, and that the C‐terminal region of PHL4 is also disordered. Additionally, we present evidence from size‐exclusion chromatography, diffusion NMR measurements, and a cross‐linking assay suggesting full‐length PHL4 forms a trimeric or tetrameric assembly. Together, the data indicate the N‐ and C‐terminal disordered domains in PHL4 flank a central folded region that likely forms the ordered oligomer of PHL4. This work provides a foundation for future studies detailing how the conformations and molecular motions of PHL4 change as it acts as a potent activator of gene expression in phosphate metabolism. Such a detailed mechanistic understanding of TF function will benefit genetic engineering efforts that take advantage of this activity to boost transcriptional activation of genes across different organisms. [ABSTRACT FROM AUTHOR]

Incorporating high volumes of fly ash (FA) in filling materials reduces costs and carbon emissions, but low early strength limits its use. This study investigates the effects of sodium sulfate decahydrate (Na2SO4·10H2O) and calcium hydroxide (Ca(OH)2) as activators at concentrations of 0.5%, 1.0%, 1.5%, and 2.0% on the mechanical properties and microstructure of tailings–cement–fly ash composites. Compressive strength testing, X-ray diffraction (XRD), and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) were used to evaluate performance at different curing stages. Results indicate that all activators enhance early strength, with 2.0% Ca(OH)2 yielding the greatest improvement. Microstructural analysis showed that activators boost quartz reactivity and create denser structures. Na2SO4 promotes ettringite and gypsum formation, while Ca(OH)2 increases alkalinity, enhancing gel formation from FA. These findings clarify how activators improve the performance of activated fly ash–cement paste (AFCP). [ABSTRACT FROM AUTHOR]

Lanthanum phosphate is a well‐known potential host for rare earth activators for phosphor‐converted white LED application. Na+ and Bi3+ codoped Eu3+ activated LaPO4 nanophosphor is successfully synthesized using citrate‐based hydrothermal method at ambient condition and confirmed by XRD, EDS and XPS analysis. The excitation spectra of the sample exhibit sharp f‐f characteristics peak of Eu3+ at 393 nm that is found to be the most dominant. The comparative photoluminescence studies of La1‐xPO4:xEu3+(x = 0.10), La1‐x‐y PO4:xEu3+, yNa+(x = 0.10, y = 0.05), and La1‐x‐y‐zPO4:xEu3+, yNa+, zBi3+ (x = 0.10, y = z = 0.05) reveal a progressive enhancement of the orange emission from Eu3+ as Na+ and (Na+, Bi3+) ions are incorporated into the LaPO4 matrix. The dominance of 5D0‐7F1 magnetic dipole transition contributing a major part of orange luminescence of the nanophosphors and the symmetric site occupancy of Eu3+ was justified from the observed trend of Ω4>Ω2$$ {\varOmega}_4>{\varOmega}_2 $$ in the Judd–Ofelt intensity parameters. The CIE studies confirm the improvement in color purity of emission from 32.5% to 90.6% due to the presence of Na+ and Bi3+ions. [ABSTRACT FROM AUTHOR]

This research aims to replace the activator NH4Cl in a vanadizing agent and reduce air pollution and harm to the human body. This study adopts powder pack cementation to prepare the vanadizing layer on the surface of GCr15 steel, focusing on the influence of the activator types (NH4Cl, CuCl, CuCl+Cr powder, and CuCl+Ni powder) on the structure and properties of the vanadizing layer on the surface of GCr15 steel. The results show that the vanadizing layer is prepared on the surface of GCr15 steel with different activators and that they are closely bonded to the matrix. The main phase composition of the vanadizing layer is VCx, and it has a preferred orientation on the (111) crystal surface. When the type of activator is NH4Cl, the prepared vanadizing layer has a lower friction factor. When the activator type is CuCl+Cr powder, the prepared vanadizing layer has less inclusions, the thickness of the vanadizing layer is the highest at 10.87 μm, and the hardness is the highest at 2331.7HV. Considering the thickness of the layer, the hardness, and the wear resistance, the best performance of the vanadizing layer was obtained when the activators were CuCl+Cr powder. [ABSTRACT FROM AUTHOR]

This study addresses the increasing demand for eco-friendly rubber compounding additives by exploring greensynthesized zinc oxide (ZnO) nanoparticles. The green synthesis of ZnO nanoparticles is gaining attention due to its ecofriendly approach and potential applications. This study investigates the synthesis of ZnO nanoparticles using sweet lime peel extract as a green method, comparing it with chemical synthesis. The obtained nanoparticles are characterized and evaluated for suitability as activators in natural rubber composites for tire applications. Furthermore, the cytotoxicity of the prepared ZnO nanoparticles on mice cells is assessed, revealing lower toxicity for green-synthesized ZnO compared to chemically synthesized ZnO. Payne effect analysis on the composites demonstrates improved polymer-filler interaction and mechanical properties for the green-synthesized ZnO-loaded composites. Notably, the incorporation of green-synthesized ZnO leads to significant enhancements in tensile strength due to its higher surface area. It achieves desirable magic triangle tire properties, including low rolling resistance, high wet traction, and high abrasion resistance. These findings highlight the promising potential of green ZnO as an environmentally friendly alternative to chemical ZnO in rubber compounding. [ABSTRACT FROM AUTHOR]

To explore formation and failure mechanism of rebar passivation film in the liquid-phase environment of alkali-activated slag (AAS) system, AAS cementitious material systems with different mixing designs were prepared. The time-dependent evolution of the pH value of AAS real pore solution was studied in various factors such as different types of activator, alkali equivalent, water-glass modulus, fly ash addition, and curing time. In addition, the generation time, composition, thickness, and critical chloride threshold of rebar passivation film in simulated pore solution were monitored and analyzed over time. The results show that the pH value of AAS real pore solution decreases with the increase of curing time, with pH values of all samples remaining above 12. 8 at 28 d. The increase in pH value in the simulated pore solution reduces the formation time of rebar passivation film, increases its thickness, and enhances its resistance to chloride ion erosion. The characteristic of AAS real pore solution having a higher pH value can provide a more favorable liquid phase environment for the stable existence of rebar passivation film, thereby improving the long-term performance of reinforced concrete structures. [ABSTRACT FROM AUTHOR]

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Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office 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.)

Geopolymer is a novel eco-friendly biodegradable cementitious material for which the emergence is expected to reduce the carbon-dioxide emission caused by Portland cement manufacturing companies. Geopolymer material possesses exceptional mechanical properties and other admirable properties such as fire and corrosion resistance. Most industrial solid wastes (ISW) and waste smoldering bottom ash (WSBA) are stacked up, filling land mass, besides their harmful influence on the surroundings. Reprocessing could make them suitable for use as materials for making geopolymers. They can efficiently adsorb heavy metals, dyes or pigments, and other radioactive contaminants, which is very helpful to humanity's future development. On the other hand, due to the exceptional features of geopolymer material, its functions go further than that. Specific helpful information regarding geopolymer materials was made known in this study. The study encompassed the source of geopolymer materials, the geopolymerization process, the categories of activators, their formation techniques, and the diverse usage areas of geopolymer materials. Furthermore, the factors influencing the mechanical features of geopolymer materials were discussed. Finally, these materials' inadequacies and usage precincts were summarized, and their evolution was abridged to prepare a theoretical or hypothetical base for the lasting improvement of geopolymer materials.

Abstract Alkali Activated Slag Concrete (AASC) has been a sustained research activity over the past two decades. Its promising characteristics and being environmentally friendly compared to Ordinary Portland Cement made AASC of exceptional interest. However, there is still no firm mix design, for the AASC, that can provide desirable fresh and hardened properties based on the composition of the binder and activator. This research specifically aims to investigate the affecting parameters on the slump and compressive strength of alkali-activated slag/lime-based concrete and provide a better understanding of the potential reasons for these characteristics. The experimental program consisted of two stages; the first stage studied the effect of different binder and activator compositions, and the second stage studied the water-to-binder ratio and binder content effects on the slump and compressive strength of alkali-activated slag/lime-based concrete. The binder and activator compositions were defined through two main parameters, the hybrid factor (HF = CaO/Si2O + Al2O3) and the solution modulus (Ms = SiO2/Na2O). The compressive strength, initial slump, and slump loss were measured to evaluate the different mixes and specify the optimum range of compositions. Based on the studied parameters, the effective range to achieve desirable slump and concrete compressive strength is from HF 0.6 up to 0.8 at Ms 1.5, this would achieve a compressive strength of more than 30 MPa and a slump of 100 mm after 90 min.

In this paper, based on the advantages of fly ash geopolymer-stabilized soil, two kinds of low-calcium fly ash was used as the raw material, sodium hydroxide and water glass as the exciter to study the factors affecting the unconfined compressive strength of the geopolymer stabilized silty soil through three kinds of sample preparation method. The results show that among the three influencing factors, sample preparation method has the greatest influence on the unconfined compressive strength, followed by the type of activator and the fineness of fly ash. At 7 days of curing, the unconfined compressive strength of fly ash-based geopolymer stabilized soil activated by NaOH demonstrated a greater increase compared to that activated by Na2SiO3. However, at the 28-day curing mark, the activation effect of Na2SiO3 on the soil's strength surpassed that of NaOH. Directly mixed components exhibit unconfined compressive strengths that are 30% to 50% higher than those of sequentially mixed components that have undergone soil confinement. Through SEM observation and pore analysis of the specimens under different factors, it was found that the gap in the material was mainly filled by the generated geopolymer gel material, to reduce the porosity and improve the compressive strength of the stabilized soil. [ABSTRACT FROM AUTHOR]

The objective of this study was to compile the currently available evidence regarding the functional and morphologic outcomes of functional orthodontic therapy for mandibular condyle fracture. We performed searches in PubMed and Google Scholar as well as manually (IOK issues 2008–2019) using the keywords "trauma", "TMJ", "activator", "condylar fracture", "fracture", "mandibular condylar fracture", "occlusal splint" and "functional appliance". Screening and analysis of study eligibility were performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The search strategy identified 198 studies published between 1971 and 2018, with 93 studies remaining after removing duplicate hits. Of the 93 studies, 19 were included in this study, considering the inclusion criteria. There were 12 follow-up, 4 prospective, and 3 purely retrospective studies. Some of the studies showed good functional results of mandibular condyle fracture treatment, in addition to subjective patient satisfaction. The incisal edge difference could be increased to physiological ranges of >35 mm by means of activator therapy. Partial mandibular deviations to the fractured side remained post-therapy, especially after unilateral fractures. Fractures without significant dislocation and luxation showed radiographic changes in shape, described as hypoplastic and ellipsoid, in addition to good morphologic results. One study found that collum length shortened twofold after a luxated fracture compared with fractures without significant dislocation, despite activator therapy. Straightening of the fragment occurred only in the low-dislocated fragments. Overall, children showed a higher remodeling potential than adult patients. Several studies observed an improved clinical outcome for functional therapy after mandibular condyle fracture. The outcome is essentially determined by fracture type, fracture height, and age. Further studies, especially prospective studies, are necessary to improve the evidence of functional orthodontic therapy for mandibular condyle fractures. [ABSTRACT FROM AUTHOR]

Although self-adhesive resin cements are convenient and less technique-sensitive materials for dental clinicians, they exhibit a lower degree of conversion due to acidic components in their composition. Supplementation of the initiator, accelerator, and activator in self-adhesive resin cements has been suggested to compensate for the lower degree of conversion. This study aimed to evaluate the effects of different combinations of self-curing initiators, self-curing activators, and accelerators on the degree of conversion (DC) of self-adhesive resin cements. A dual-cured self-adhesive resin was prepared using six combinations of initiators, activators, and accelerators. The change in the DC over time was evaluated with and without light curing. The film thickness, flow properties, and cytotoxicity of each formulation were assessed. The results showed that all supplemental components had an effect on increasing the DC, but a greater increase in the DC was observed in the following order: activator, accelerator, and initiator. The cytotoxicity of the resin cements was related to the DC values, as resin cements with lower DC values exhibited higher cytotoxicity. The film thickness met the ISO standards for all groups. The results suggest that utilizing an activator is the most effective approach to enhance the DC in self-adhesive resin cement and that cytotoxicity tended to increase with lower DC values, whereas film thickness and flow properties demonstrated no correlation with DC values. [ABSTRACT FROM AUTHOR]

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The loss of function of AAA (ATPases associated with diverse cellular activities) mechanoenzymes has been linked to diseases, and small molecules that activate these proteins can be powerful tools to probe mechanisms and test therapeutic hypotheses. Unlike chemical inhibitors that can bind a single conformational state to block enzyme function, activator binding must be permissive to different conformational states needed for mechanochemistry. However, we do not know how AAA proteins can be activated by small molecules. Here, we focus on valosin-containing protein (VCP)/p97, an AAA unfoldase whose loss of function has been linked to protein aggregation-based disorders, to identify druggable sites for chemical activators. We identified VCP ATPase Activator 1 (VAA1), a compound that dose-dependently stimulates VCP ATPase activity up to ~threefold. Our cryo-EM studies resulted in structures (ranging from ~2.9 to 3.7 Å-resolution) of VCP in apo and ADP-bound states and revealed that VAA1 binds an allosteric pocket near the C-terminus in both states. Engineered mutations in the VAA1-binding site confer resistance to VAA1, and furthermore, modulate VCP activity. Mutation of a phenylalanine residue in the VCP C-terminal tail that can occupy the VAA1 binding site also stimulates ATPase activity, suggesting that VAA1 acts by mimicking this interaction. Together, our findings uncover a druggable allosteric site and a mechanism of enzyme regulation that can be tuned through small molecule mimicry. [ABSTRACT FROM AUTHOR]

Cellulose-based impact polypropylene copolymers (IPC) has been developed by utilizing Arenga pinnata “ijuk” fiber. The cellulose from pristine ijuk fiber (IF) was extracted via alkalization and bleaching treatment using NaClO, with KMnO4 as the activator. The purpose of using KMNO4 is to replace the use of acid buffers in every process that uses NaClO. The fibers’ properties, namely their compound content, morphology, crystallinity index, and crystallite size, were characterized and investigated to examine the treatment effect. The Fourier-transform infrared (FTIR) spectroscopy shows that the majority of lignin and hemicellulose were removed throughout the treatment process. FTIR semi-quantitative analysis, based on absorbance ratio, reveals that IFB5, the fiber treated with 5% NaClO for 5 h, exhibits the highest cellulose content. The scanning electron microscopy (SEM) was performed to observe the fibers’ morphology. The X-ray diffraction (XRD) characterization reveals that IFB5 contains cellulose Iβ type and exhibits the highest crystallinity index, 62.27%. The fiber was then utilized to develop a cellulose-based IPC composite. The IPC Ijuk Treatment (IPC Ijuk T) shows a good bonding characteristic between fiber and the matrix, the highest crystallinity percentage, 67,18%, the lowest melting point, 162.8 °C, and the highest thermal stability, started to degrade at 265 °C and decomposed at 447 °C. Thus, IPC Ijuk T can be considered applicable as IPC composite filler.

Abstract Soluble guanylate cyclase (sGC) modulation has been scrutinized in several disease states including heart failure (HF). Recently, it was shown that an sGC modulator improved HF-related hospitalization significantly, though, there was no benefit related to mortality. Herein, a comprehensive meta-analysis of randomized controlled trials (RCTs) for sGC modulation in HF patients was provided in agreement with the PRISMA statement. A total of 10 RCTs yielding 12 papers were included. There were 7526 patients with heart failure of each phenotype, 4253 in the sGC modulator group and 3273 in the placebo group. Use of sGC modulators in HF patients yielded no significant difference in the risk of all-cause mortality compared to placebo (RR = 0.97, 95% CI 0.88–1.08, p = 0.62). The use of sGC modulators was associated with a trend toward a considerable but non-significant increase in the incidence of SAEs (RR = 1.10, 95% CI 0.99–1.22, p = 0.07), as well as an increased incidence of hypotension and anemia. There was an overall neutral effect of sGC modulation on NT-proBNP levels, 6MWD and mortality, at a cost of slight increase in hypotension and anemia. Of note, the improvement in EQ-5D-based quality of life was significant. Hence, the benefit seems to be driven by distinctive domains of quality of life.

Strong-alkali activation is a prerequisite needed to ensure the full polymerization activity of alkali slag binder and establish excellent mechanical properties; however, it substantially increases the preparation cost. In this study, the effects of both strong and weak alkaline activators on the activation performance of alkali slag were examined, using a combination of X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis methods. The reaction mechanism was analyzed under different alkaline conditions, and the preparation cost could be significantly reduced without significantly degrading mechanical properties. The results indicate that Ca(OH)2 can stimulate the reactivity of slag, resulting in a 40% decrease in compressive strength (compared to NaOH) but a 25–50% reduction in preparation cost. With increasing Ca(OH)2 dosage, the compressive strength first increases and then decreases. The best excitation effect is achieved at a dosage of 40 g Ca(OH)2 per 450 g GBFS. The formation of aluminosilicate is the main driving force for the observed increase in compressive strength. Excessive dosage of Ca(OH)2 will lead to its deposition in the specimen, thus affecting the development of compressive strength.

Aging and age-related diseases are associated with a decline in the capacity of protein turnover. Intrinsically disordered proteins, as well as proteins misfolded and oxidatively damaged, prone to aggregation, are preferentially digested by the ubiquitin-independent proteasome system (UIPS), a major component of which is the 20S proteasome. Therefore, boosting 20S activity constitutes a promising strategy to counteract a decrease in total proteasome activity during aging. One way to enhance the proteolytic removal of unwanted proteins appears to be the use of peptide-based activators of the 20S. In this study, we synthesized a series of peptides and peptidomimetics based on the C-terminus of the Rpt5 subunit of the 19S regulatory particle. Some of them efficiently stimulated human 20S proteasome activity. The attachment of the cell-penetrating peptide TAT allowed them to penetrate the cell membrane and stimulate proteasome activity in HEK293T cells, which was demonstrated using a cell-permeable substrate of the proteasome, TAS3. Furthermore, the best activator enhanced the degradation of aggregation-prone α-synuclein and Tau-441. The obtained compounds may therefore have the potential to compensate for the unbalanced proteostasis found in aging and age-related diseases. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office 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.)

This research aimed to optimize the production conditions for geopolymer matrices by investigating the combination of heat curing conditions and the incorporation of recycled ceramic fines (CFs) as a partial replacement material for fly ash (FA). The obtained physical and mechanical properties of the composites confirmed the positive impact resulting from increasing the curing temperature from 65 °C to 85 °C and using CFs in the amount of 37.5% as a replacement for FA. The results were from laboratory tests performed to evaluate compressive strength, bending strength, bulk density, and water absorption of the geopolymer mixes. In addition, microscopic observations and porosity assessment were also performed, which confirmed that a further increase in the replacement of FA by CFs causes an increase in the porosity of the mixes and, thus, a decrease in all the assessed properties that are relevant to their practical use. [ABSTRACT FROM AUTHOR]

In industrial manufacturing, pyrrhotite(Fe1−xS), once depressed, is commonly activated for flotation. However, the replacement of CuSO4 is necessary due to the need for exact control over the dosage during the activation of pyrrhotite, which can pose challenges in industrial settings. This research introduces the use of FeSO4 for the first time to efficiently activate pyrrhotite. The impact of two different activators on pyrrhotite was examined through microflotation experiments and density functional theory (DFT) calculations. Microflotation experiments confirmed that as the CuSO4 dosage increased from 0 to 8 × 10−4 mol/L, the recovery of pyrrhotite initially increased slightly from 71.27% to 87.65% but then sharply decreased to 16.47%. Conversely, when the FeSO4 dosage was increased from 0 to 8 × 10−4 mol/L, pyrrhotite's recovery rose from 71.27% to 82.37%. These results indicate a higher sensitivity of CuSO4 to dosage variations, suggesting that minor alterations in dosage can significantly impact its efficacy under certain experimental conditions. In contrast, FeSO4 might demonstrate reduced sensitivity to changes in dosage, leading to more consistent performance. Fe ions can chemically adsorb onto the surface of pyrrhotite (001), creating a stable chemical bond, thereby markedly activating pyrrhotite. The addition of butyl xanthate (BX), coupled with the action of Fe2+ on activated pyrrhotite, results in the formation of four Fe-S bonds on Fe2+. The proximity of their atomic distances contributes to the development of a stable double-chelate structure. The S 3p orbital on BX hybridizes with the Fe 3d orbital on pyrrhotite, but the hybrid effect of Fe2+ activation is stronger than that of nonactivation. In addition, the Fe-S bond formed by the addition of activated Fe2+ has a higher Mulliken population, more charge overlap, and stronger covalent bonds. Therefore, Fe2+ is an excellent, efficient, and stable pyrrhotite activator. [ABSTRACT FROM AUTHOR]

The influence of additive MgO and its content on both the compressive strength and carbonation depth of alkali-activated slag concrete (AASC) was investigated under an accelerated carbonation environment. Furthermore, the modification mechanism of MgO on the carbonation resistance of AASC was explored by multiple analytical techniques. Results showed that the incorporation of MgO effectively enhanced the post-carbonation compressive strength and diminished the carbonation depth of concrete. As the MgO content increased, there was a gradual reduction in carbonation depth. The incorporation of MgO promotes the hydration of slag, altering the Al environment, and promoting the formation of C-S-H and Mg-Al hydrotalcite phases. Moreover, the addition of MgO resulted in the emergence of magnesium carbonate and calcium magnesium carbonate in the carbonation products, which filled the pores and prevented the further diffusion of CO2 into the interior. In addition, the improvement effects are more pronounced in the water glass system compared to the NaOH system. [ABSTRACT FROM AUTHOR]

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Half-sandwich titanium complexes, specifically Cp*TiCl3 and Cp*Ti[O(2,6-iPr2-Ph)]Cl2, were investigated as catalytic precursors for the synthesis of ethylene/propylene copolymers and ethylene/propylene/5-ethylidene-2-norbornene terpolymers. For this purpose, a variety of activators were tested: modified polymethylaluminoxane; boron-containing compounds such as B(C6F5)3 and Ph3CB(C6F5)4 in combination with triisobutylaluminum (TIBA); isobutylaluminoxane (IBAO), and isobutylaluminum aryloxide (2,6-tBu2,4-Me-PhO-)AliBu2 (AlBHT). In the copolymerization of ethylene and propylene, the catalysts exhibited high activity when activated by MMAO-12 and TIBA+Ph3CB(C6F5)4 but low activity with TIBA+B(C6F5)3 and AlBHT. With IBAO as an activator, these catalysts were found to be totally ineffective. The catalysts exhibited low activity in terpolymerization. It was further revealed that more than one type of active sites was generated in the catalytic systems: these sites were responsible for simultaneous formation of low-molecular-weight and ultrahigh-molecular-weight polymers. The composition of the copolymers as well as their thermophysical and physicomechanical properties were shown to depend on the type and composition of the catalytic system. [ABSTRACT FROM AUTHOR]

Copyright of Foundry Technology (1000-8365) is the property of Foundry Technology Editorial Office 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.)

Soluble guanylate cyclase (sGC) modulation has been scrutinized in several disease states including heart failure (HF). Recently, it was shown that an sGC modulator improved HF-related hospitalization significantly, though, there was no benefit related to mortality. Herein, a comprehensive meta-analysis of randomized controlled trials (RCTs) for sGC modulation in HF patients was provided in agreement with the PRISMA statement. A total of 10 RCTs yielding 12 papers were included. There were 7526 patients with heart failure of each phenotype, 4253 in the sGC modulator group and 3273 in the placebo group. Use of sGC modulators in HF patients yielded no significant difference in the risk of all-cause mortality compared to placebo (RR = 0.97, 95% CI 0.88–1.08, p = 0.62). The use of sGC modulators was associated with a trend toward a considerable but non-significant increase in the incidence of SAEs (RR = 1.10, 95% CI 0.99–1.22, p = 0.07), as well as an increased incidence of hypotension and anemia. There was an overall neutral effect of sGC modulation on NT-proBNP levels, 6MWD and mortality, at a cost of slight increase in hypotension and anemia. Of note, the improvement in EQ-5D-based quality of life was significant. Hence, the benefit seems to be driven by distinctive domains of quality of life. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme with diverse biological functions in DNA synthesis. Nicotinamide phosphoribosyltransferase (NAMPT) is a key rate‐limiting enzyme involved in NAD+ biosynthesis in mammals. We developed the first chemical tool for optical control of NAMPT and NAD+ in biological systems using photoswitchable proteolysis‐targeting chimeras (PS‐PROTACs). An NAMPT activator and dimethylpyrazolazobenzene photoswitch were used to design highly efficient PS‐PROTACs, enabling up‐ and down‐reversible regulation of NAMPT and NAD+ in a light‐dependent manner and reducing the toxicity associated with inhibitor‐based PS‐PROTACs. PS‐PROTAC was activated under 620 nm irradiation, realizing in vivo optical manipulation of antitumor activity, NAMPT, and NAD+. [ABSTRACT FROM AUTHOR]

NaCaYF6 is the formula for gagarinite. Noting the lack of luminescence studies in this material, we synthesized it using the hydrothermal method and investigated the luminescence of several lanthanides. Characteristic luminescence of Eu3+, Dy3+, Sm3+ and Tb3+ was observed. Detailed results on photoluminescence emission and excitation spectra, lifetime, chromaticity coordinates and concentration dependence of emission intensity are presented. Except for Tb3+, which exhibits f-d excitation, the luminescence of other activators got quenched at 1mol % concentration. Eu3+ emission in this host was peculiar, in that the emissions from higher 5D states were observed. Luminescence characteristics are explained using the known energy level diagrams for the lanthanide activators. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme with diverse biological functions in DNA synthesis. Nicotinamide phosphoribosyltransferase (NAMPT) is a key rate‐limiting enzyme involved in NAD+ biosynthesis in mammals. We developed the first chemical tool for optical control of NAMPT and NAD+ in biological systems using photoswitchable proteolysis‐targeting chimeras (PS‐PROTACs). An NAMPT activator and dimethylpyrazolazobenzene photoswitch were used to design highly efficient PS‐PROTACs, enabling up‐ and down‐reversible regulation of NAMPT and NAD+ in a light‐dependent manner and reducing the toxicity associated with inhibitor‐based PS‐PROTACs. PS‐PROTAC was activated under 620 nm irradiation, realizing in vivo optical manipulation of antitumor activity, NAMPT, and NAD+. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme with diverse biological functions in DNA synthesis. Nicotinamide phosphoribosyltransferase (NAMPT) is a key rate‐limiting enzyme involved in NAD+ biosynthesis in mammals. We developed the first chemical tool for optical control of NAMPT and NAD+ in biological systems using photoswitchable proteolysis‐targeting chimeras (PS‐PROTACs). An NAMPT activator and dimethylpyrazolazobenzene photoswitch were used to design highly efficient PS‐PROTACs, enabling up‐ and down‐reversible regulation of NAMPT and NAD+ in a light‐dependent manner and reducing the toxicity associated with inhibitor‐based PS‐PROTACs. PS‐PROTAC was activated under 620 nm irradiation, realizing in vivo optical manipulation of antitumor activity, NAMPT, and NAD+. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme with diverse biological functions in DNA synthesis. Nicotinamide phosphoribosyltransferase (NAMPT) is a key rate‐limiting enzyme involved in NAD+ biosynthesis in mammals. We developed the first chemical tool for optical control of NAMPT and NAD+ in biological systems using photoswitchable proteolysis‐targeting chimeras (PS‐PROTACs). An NAMPT activator and dimethylpyrazolazobenzene photoswitch were used to design highly efficient PS‐PROTACs, enabling up‐ and down‐reversible regulation of NAMPT and NAD+ in a light‐dependent manner and reducing the toxicity associated with inhibitor‐based PS‐PROTACs. PS‐PROTAC was activated under 620 nm irradiation, realizing in vivo optical manipulation of antitumor activity, NAMPT, and NAD+. [ABSTRACT FROM AUTHOR]