cytochrome c (cyt c ) is released from mitochondria into the cytosol upon apoptotic stimulation, ultimately triggering programmed cell death. Recent studies have revealed that transfer RNA (tRNA) interacts with cyt c ...
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cytochrome c (cyt c ) is released from mitochondria into the cytosol upon apoptotic stimulation, ultimately triggering programmed cell death. Recent studies have revealed that transfer RNA (tRNA) interacts with cyt c , impeding the formation of the apoptosome complex and thereby suppressing apoptosis. To elucidate the molecular mechanism underlying the interaction between cyt c and tRNA, nuclear magnetic resonance (NMR)-based chemical shift perturbation and intensity analysis were employed to characterize the binding interface between cyt c and tRNA phe . The findings demonstrate that cyt c primarily engages with tRNA phe through its 70-85 Ω-loop and N-terminal α-helix. This interaction sterically hinders the accessibility of small molecules, such as H 2 O 2 , to the hydrophobic pocket of cyt c , consequently attenuating its peroxidase activity. Furthermore, oxidative modification of cyt c , particularly the carbonylation of positively charged lysine residues, weakens this interaction.
A new integrated filler metal/base metal manufacturing method by cold spray additive manufacturing is proposed. The integrated cuTi filler metal/GH3536 and cuTi + W composite filler metal/GH3536 are prepar...
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A new integrated filler metal/base metal manufacturing method by cold spray additive manufacturing is proposed. The integrated cuTi filler metal/GH3536 and cuTi + W composite filler metal/GH3536 are prepared by cold spray additive manufacturing techniques. The large plastic deformation of cu and Ti particles and the tamping effect of W particles promote the interfacial bonding of particles, which improves the weldability of cold sprayed cuTi + W composite filler metals. Based on the cold sprayed cuTi + W composite filler metal, the c f /Siccomposites and GH3536 are successfully brazed, and the typical microstructure and brazing mechanism are investigated. As a result, the shear strength of c f /Sic-GH3536 joint brazed by cold sprayed cuTi + W composite filler metal reaches 77 MPa. This study highlightes the great potential of cold spray additive manufacturing for integrated filler metal/base metal manufacturing in brazing.
Following the 2011 Fukushima Daiichi nuclear catastrophe, there has been a significant surge in interest towards innovative materials capable of enhancing the safety, performance, and efficiency of nuclear reactors. T...
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Following the 2011 Fukushima Daiichi nuclear catastrophe, there has been a significant surge in interest towards innovative materials capable of enhancing the safety, performance, and efficiency of nuclear reactors. This study introduces a new class of layered ternary compounds, specifically (Uc) n Si 3 c 2 (n = 1,2), and derived two-dimensional (2D) U 2 c, discovered through first-principles calculations. We predict the electronic, mechanical, and thermodynamic properties of these compounds within the PBE and PBE + U frameworks, with a comparative analysis of the (Uc) n Al 3 c 2 (n = 1,2) series. Our findings reveal that the USi 3 c 3 and U 2 Si 3 c 4 compounds exhibit mechanical and dynamic stabilities, suggesting their potential for experimental synthesis under specificconditions. These compounds demonstrate superior mechanical and thermal properties as nuclear fuels, including higher elastic moduli and improved ductility compared to (Uc) n Al 3 c 2 compounds. The mechanical and dynamical stabilities of 2D U 2 c are confirmed, and the calculated thermal conductivity and mechanical properties position it as a promising candidate for high-performance nuclear fuel applications. We anticipate that the present work will bolster future experimental endeavors and help explore the practical applications of these novel materials in future nuclear systems.
The increasing concentrations of emerging organiccontaminants (EOcs) in wastewater threaten human health and the environment. Their complex structures, low concentrations, and conversion into secondary metabolites ch...
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The increasing concentrations of emerging organiccontaminants (EOcs) in wastewater threaten human health and the environment. Their complex structures, low concentrations, and conversion into secondary metabolites challenge current remediation techniques. This study presents the Z-scheme Ti 3 c 2 MXene@ceO 2 (MX@ceO 2 ) heterostructures, synthesized by a facile in-situ sonochemical method, aimed at enhancing photocatalytic mineralization of highly toxic Doxorubicin (DOX) drug. Our findings reveal that the unique surface and structural properties of Ti 3 c 2 MXene facilitated the effective nucleation and growth of the ceO 2 . The growth mechanisms involved the adsorption of ce atoms through negatively charged functional groups, and anchoring to surface defects and vacancies in Ti 3 c 2 MXene. The formation of intimate interfacial heterojunctions between Ti 3 c 2 MXene and ceO 2 not only facilitated the charge separation and utilization but also improved the photostability, thereby improving the catalytic performance of the composite. Photodegradation experiments demonstrated 96% removal of DOX within 240 min of visible light exposure. Moreover, high-performance liquid chromatography analysis confirmed the complete mineralization of DOX. The post degradation analysis revealed the minimal cytotoxicity induced by photodegraded residues. The stability and sustained catalytic efficiency of MX@ceO 2 in degrading DOX into non-toxic residues position such Z-scheme heterostructures as promising candidates for long-term remediation of EOcs.
A meticulous design of the local environment at the interface between active species and the support, aimed at optimizing the adsorption of H 2 O molecules and BH 4 ⁻ anion, offers an ideal strategy for enhancing hydr...
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A meticulous design of the local environment at the interface between active species and the support, aimed at optimizing the adsorption of H 2 O molecules and BH 4 ⁻ anion, offers an ideal strategy for enhancing hydrogen generation via NaBH 4 hydrolysis through dual activation pathways. Theoretical predictions based on d-band center analysis and electron transfer calculations suggest that introducing -OH functional groups induce charge redistribution, enhancing charge concentration on alk-Ti 3 c 2 and facilitating the adsorption and activation of dual active species, H 2 O molecules and BH 4 ⁻ anion. Inspired by these predictions, the optimized alk-Ti 3 c 2 /RuO x catalyst demonstrates the highest catalytic activity, achieving a hydrogen generation rate (HGR) of 9468 mL min −1 g cat. −1 . Both experimental data and theoretical analyses confirm that the -OH functional groups promote charge enrichment on alk-Ti 3 c 2 , optimizing the adsorption of H 2 O molecules and BH 4 ⁻ anion, and reducing the dissociation energy barrier of the *OH-H-TS intermediate. This dual activation pathways mechanism lowers the activation energy for NaBH 4 hydrolysis, significantly enhancing the HGR performance. These findings, guided by theoretical insights, establish alk-Ti 3 c 2 /RuO x as an efficient catalyst for NaBH 4 hydrolysis and provide a strong foundation for future hydrogen generation catalyst designs.
c -Glycosides, known for their superior in vivo stability compared to their O - and N -glycoside counterparts, have been widely explored as drug candidates and utilized in biological research. Traditional radical c-gl...
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c -Glycosides, known for their superior in vivo stability compared to their O - and N -glycoside counterparts, have been widely explored as drug candidates and utilized in biological research. Traditional radical c-glycosidation techniques have relied on precursors such as glycosyl halides and glycosyl sulfones. These methods, however, face several challenges, including the instability of glycosyl precursors, the requirement for multi-step synthesis, and limited practicality. Herein, we present a straightforward, metal-free method to synthesize both sp 2 and sp 3 c-glycosides with high stereoselectivity via direct deoxy-glycosidation of readily available and stable 1-hydroxycarbohydrates. Mechanistic investigations indicate the involvement of glycosyl radicals in the reaction. cellular assays reveal the antitumor activity of the synthesized products, which underscores the potential of this strategy in medicinal chemistry.
ABSTRAcTDifferent natural and anthropogenic drivers impact the groundwater in the catchment area of the southern Baltic Sea, north-eastern Germany. To understand the sources and fate of dissolved sulphate, carbonate, ...
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ABSTRAcTDifferent natural and anthropogenic drivers impact the groundwater in the catchment area of the southern Baltic Sea, north-eastern Germany. To understand the sources and fate of dissolved sulphate, carbonate, and nitrate on a regional scale, in the present study, the hydrogeochemical and multi-stable isotope (H, c, O, S) composition of groundwater samples from up to more than 300 sites (depths from near-surface down to 291 m) was studied. To investigate the element sources and the water–rock–microbe interaction processes that took place along the groundwater flow path, a mass balance approach is combined with physico-chemical modelling. Microbial oxidation of pyrite using nitrate as electron acceptor and a superimposition by dissimilatory sulphate reduction at depth is shown in a drilled vertical profile at one site. This trend frames the behaviour of sulphate at many investigated groundwater wells. Dissolved inorganiccarbon (DIc) in the groundwater was found to be controlled by the uptake of biogeniccarbon dioxide, the dissolution of carbonate minerals, thein situoxidation of DOc and, at a few sites, the formation and/or oxidation of biogenic methane. Enhanced groundwater DIc loads may potentially increase future cO2degassing to the atmosphere upon release of groundwaters to the surface. These results form a comprehensive base for understanding the present situation and for future investigations.
One effective strategy for mitigating carbon emissions is utilizing carbon dioxide as a substrate to synthesize high-value multi-carbon products through the electrochemical cO 2 reduction reaction (cO 2 RR). Despite t...
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One effective strategy for mitigating carbon emissions is utilizing carbon dioxide as a substrate to synthesize high-value multi-carbon products through the electrochemical cO 2 reduction reaction (cO 2 RR). Despite the widespread application of c 3+ oxygenated hydrocarbons, including propanol, acetone, and butanol, in numerous industrial chemical processes, the literature provides scant reporting on their role in electrochemical cO 2 reduction reactions. In this review, the reaction mechanisms specific to predominant c 3 products are analyzed in detail. Subsequently, we outline advancements concerning three distinct variants of cu-based catalysts, namely 1) cu oxide-derived catalysts, 2) cu nanoparticle catalysts, and 3) cu single atoms and molecular cu catalysts. Meanwhile, the feasibility of designing copper-based tandem catalytic systems to produce c 3+ products in cO₂RR is also discussed. Additionally, the review explores the emergence of non-cu-based catalysts, particularly nickel (Ni)- and molybdenum (Mo)-based transition-metal phosphides and chalcogenides. These systems, with the characterization of high catalytic efficiency, excellent stability and low cost, provide sustainable and economical alternatives. The integration of such catalysis offers promising solutions to overcome existing limitations, paving the way for efficient, scalable, and sustainable cO 2 RR technologies. Besides artificial intelligence (AI) and machine learning (ML) combined with DFT and high-throughput (HT) experiments, as a new paradigm shift in data-driven catalyst exploration, this review addressed some promising recent work for catalysts to yield c 3+ products from cO 2 RR on that edge.
Novel 2D nanomaterials offer the potential in addressing environmental challenges such as pollution and waste management, water scarcity, and agricultural limitations. While their catalytic and oxidative properties ai...
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Novel 2D nanomaterials offer the potential in addressing environmental challenges such as pollution and waste management, water scarcity, and agricultural limitations. While their catalytic and oxidative properties aid pollutant degradation, carbon sequestration, water treatment, and crop improvement, thorough phytotoxicity evaluation is necessary before application. In our study, we developed Ti 3 c 2 T x MXene and MoAlB@MBene, each showcasing unique structures and chemistries. DLS, zeta potential, and EDS analyses elucidated their size distribution, stability, and elemental composition. XRD confirmed efficient MAX into MXene transformation and MBene’s single-phase nature, while FT-IR suggested relatively pure surface chemistries. UV-Vis spectroscopy revealed plasmonic peaks for MXene, and UV absorption edge for MBene. To assess biological impact, we conducted a phytotoxicity evaluation based on germination efficiency, root and shoot elongation, biomass accumulation, and chlorophyll quantitative and qualitative studies. Ecotoxicity assessments on higher plants revealed MXene's concentration-dependent phytotoxicity, in contrast to growth-promoting MBene. Microscopic observations detailed MXene-induced root meristem disruptions, while MBene stimulated lateral root growth. Mass analyses demonstrated MXene-induced dry mass increases, even by 22 % at 1000 mg dm −3 , relative to the control, contrasting with MBene’s vitality preservation and the carbon cycle. chlorophyll and its fluorescence studies revealed MXene-induced stress, whereas MBene exhibited positive or neutral. crucially, XRF analysis suggested limited nanomaterial uptake by plants. Altogether, our study introduces a novel approach to evaluating 2D nanomaterials' phytotoxicity, emphasizing the need to understand potential risks before application. While these materials offer environmental benefits, our findings show that careful evaluation is key to ensuring safe and sustainable use in real-world scenario. S
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