Dinuclear Research Articles

PANoptosis-related molecular clustering and prognostic signature associated with the immune landscape and therapy response in breast cancer.

Breast cancer (BC) remains one of the most pervasive and complex malignancies. PANoptosis represents a recently identified cellular mechanism leading to programmed cell death. However, the prognostic implications and influence on the immune microenvironment of BC pertaining to PANoptosis-related genes (PRGs) remain significantly understudied. We conducted differential expression analysis to identify prognostic-Related PRGs by the Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Next, we identified the PANoptosis-related molecular subtype using the consensus clustering analysis, and constructed and validated the PANoptosis-related prognostic signature using LASSO and Cox regression analyses. ROC curves were employed to assess the performance of the signatures. Furthermore, drug sensitivity between low- and high-risk group were analysis. Finally, we conducted RT-qPCR to assess the gene expression levels involved in this signature. We categorized BC patients into 2 distinct molecular clusters based on PRGs and identified differentially expressed genes associated with prognosis. Subsequently, BC patients were then divided into 2 gene clusters. The identified PRGs molecular clusters and gene clusters demonstrated association with patient survival, immune system functions, and biological processes and pathways of BC. A prognostic signature comprising 5 genes was established, and BC patients were classified into low- and high-risk groups based on the risk scores. The ROC curves demonstrated that those in the low-risk category exhibited notably extended survival compared to the high-risk group. A nomogram model for patient survival was constructed based on the risk score in conjunction with other clinical features. High-risk group had higher tumor burden mutation, CSC index and lower StomalScore, ImmuneScore, and ESTIMATEScore. Subsequently, we established a correlation between the risk score and drug sensitivity among BC patients. Finally, qRT-PCR results showed that the expression of CXCL1, PIGR, and TNFRSF14 significantly decreased, while CXCL13 and NKAIN were significantly increased in BC tissues. We have developed a molecular clustering and prognostic signature based on PANoptosis to improve the prediction of BC prognosis. This discovery has the potential to not only assist in assessing overall patient prognosis but also to deepen our understanding of the underlying mechanisms of PANoptosis in BC pathogenesis.

Improvement of seismic performance of concrete structures using magnetized concrete: an empirical study

High-Performance Concrete (HPC) offers better workability, compressive strength, and durability compared to ordinary concrete. One type of high-strength concrete is magnetic concrete. The primary objective of this empirical research is to investigate the potential of magnetized concrete in enhancing the seismic properties of concrete structures, in this technology, the physical structure of water is altered by inducing a magnetic field. The research employs empirical methods, including experimental testing and analysis, to assess the seismic performance of magnetized concrete compared to traditional concrete. As a result, the number of molecules in a molecular cluster decrease from 13 to 5 or 6, and the surface tension of the water is reduced. Using this water in concrete preparation increases the workability of the concrete mix and reduces the required water. Additionally, by facilitating cement hydration, it increases the compressive strength and durability of the concrete. This increased compressive strength enhances the stability and resistance of the structure against earthquake forces. Moreover, maintaining the compressive strength of the concrete while using magnetic water can reduce cement consumption. This reduction in cement consumption can lower the weight of the structure, which is very effective in reducing earthquake forces in tall buildings.

Complex Phase Transitions of Fully Rigid Sphere-Rod Amphiphiles Induced by Solvent Polarity in Dilute Solutions.

We report complex macrophase and microphase transitions of rigid amphiphiles with spherical Keggin molecular clusters as the solvophilic block and rod-like rigid oligofluorene (OF) as the solvophobic block in mixed solvents of water and polar organic solvent. By properly adjusting the solvent polarity, the amphiphiles are found to respond accordingly by self-assembling into multilayered incomplete onion-like structures (10-25 vol % THF), single-layered vesicular structures (60 vol % THF), and an unexpected macrophase separation in the middle (40-50 vol % THF), which is due to the anomalous trends in Keggin solubility as a result of the nature of TBA+ counterions. The rigidity of the OF block prevents the amphiphile from assembling by following the rule of packing parameters; instead, interdigitation among different rods leads to the formation of the solvophobic domain to achieve self-assembly. The incomplete onion structures are controlled by the interdigitation of rigid rods for the number of layers and the electrostatic interaction among Keggin head groups for the interlayer distance. When the degree of interdigitation becomes lower, the self-assembly process shows a trend that can be explained by the traditional rule of packing parameter. This study demonstrates the formation of different self-assembled structures by rigid amphiphiles and their transitions induced by solvent composition. The self-assembly (microphase separation) of rigid amphiphiles in a dilute solution could indeed represent a broad area containing complicated, uncharted rules.

Dative Bonding Activation Enables Precise Functionalization of the Remote B-H Bond of nido-Carborane Clusters.

The innovation of synthetic strategies for selective B-H functionalization is a pivotal objective in the realm of boron cluster chemistry. However, the precise, efficient, and rapid functionalization of a B-H bond of carboranes that is distant from the existing functional groups remains intractable owing to the limited approaches for site-selective control from the established methods. Herein, we report a dative bonding activation strategy for the selective functionalization of a nonclassical remote B-H site of nido-carboranes. By leveraging the electronic effects brought by the exopolyhedral B(9)-dative bond, a cross-nucleophile B-H/S-H coupling protocol of the distal B(5)-H bond has been established. The dative bond not only amplifies the subtle reactivity difference among B-H bonds but also significantly changes the reactive sites, further infusing nido-carboranes with additional structural diversity. This reaction paradigm features mild conditions, rapid conversion, efficient production, broad scope, and excellent group tolerance, thus enabling the applicability to an array of complex bioactive molecules. The efficient and scalable reaction platform is amenable to the modular construction of photofunctional molecules and boron delivery agents for boron neutron capture therapy. This work not only provides an unprecedented solution for the selective diversification of distal B-H sites in nido-carboranes but also holds the potential for expediting the discovery of novel carborane-based functional molecules.

Stability and Dynamics of Zeolite-Confined Gold Nanoclusters.

Nanoengineered metal@zeolite materials have recently emerged as a promising class of catalysts for several industrially relevant reactions. These materials, which consist of small transition metal nanoclusters confined within three-dimensional zeolite pores, are interesting because they show higher stability and better sintering resistance under reaction conditions. While several such hybrid catalysts have been reported experimentally, key questions such as the impact of the zeolite frameworks on the properties of the metal clusters are not well understood. To address such knowledge gaps, in this study, we report a robust and transferable machine learning-based potential (MLP) that is capable of describing the structure, stability, and dynamics of zeolite-confined gold nanoclusters. Specifically, we show that the resulting MLP maintains ab initio accuracy across a range of temperatures (300-1000 K) and can be used to investigate time scales (>10 ns), length scales (ca. 10,000 atoms), and phenomena (e.g., ensemble-averaged stability and diffusivity) that are typically inaccessible using density functional theory (DFT). Taken together, this study represents an important step in enabling the rational theory-guided design of metal@zeolite catalysts.

Overview and perspectives on metalloid tin cluster chemistry.

Although the first metalloid tin cluster was discovered by Wiberg in 1999, the number of isolated and characterized compounds is still low. However, numerous theoretical calculations indicate that a large variety of compounds are yet to be discovered, thereby suggesting that larger clusters might form a cluster-of-clusters arrangement rather than compact structures. This trend seems to be supported by the largest metalloid tin clusters exhibiting up to 20 tin atoms. In this review, recent results and future possibilities of this fascinating class of metalloid tin cluster compounds are discussed.

Exclusive catalytic hydrogenation of nitrobenzene toward p-aminophenol over atomically precise Au36(SR)24 clusters.

Despite the advances in devising green methodologies for selective hydrogenation of nitrobenzene toward p-aminophenol, it is still difficult to realize p-aminophenol as the exclusive product in heterogeneous metal catalysis, as the excessive hydrogenation of nitrobenzene usually results in the aniline byproduct. Herein we report that a metal cluster containing 36 gold atoms capped by 24 thiolate ligands provides a unique pathway for nitrobenzene hydrogenation to achieve a p-aminophenol selectivity of ∼100%. The gold cluster can efficiently suppress the over-hydrogenation of amino groups via hydroxyl rearrangement with the aid of water and sequentially the proton transfer promoted by acid toward p-aminophenol. More notably, remarkable catalytic performances can be extended to clusters with similar structures such as Au28(SR)20 and Au44(SR)28, where only an atomic layer change of 2.1 Å thickness in the Au36(SR)24 cluster can tailor the proton affinity for the amino group of the key intermediate phenylhydroxylamine, thereby altering the activity while the p-aminophenol selectivity remained.

A New Structural Motif in Aggregation of Methylalumoxanes: Non-Hydrolytic Route by the Alkylation of Dicarboxylic Acids.

Alumoxanes are typically produced via controlled hydrolysis of short-chain alkyl aluminium compounds which leads to oligomeric species that are usually difficult to obtain in crystalline form. Simultaneously, various alternative non-hydrolytic approaches to alumoxanes have also been used. In this work, we report on a new methylalumoxane scaffold derived from the alkylation of a series of dicarboxylic acids: itaconic acid (HO2CCH2C(=CH2)CO2H), succinic acid (HO2CCH2CH2CO2H) and homophthalic acid (HO2CCH2C6H4CO2H). The reactions of AlMe3 with a selected dicarboxylic acid in the molar ratio 4 : 1 conducted at elevated temperature occur with double methylation of each carboxylic group and provide to the formation of a new methylalumoxane aggregate, Me10Al6O4, flanked by methylaluminium diolate units. We also aimed to obtain dialkylaluminium derivatives of dicarboxylic acids by the controlled reaction of the appropriate acid with AlMe3 in the 1 : 2 stoichiometry. While the synthesis of organoaluminium derivatives of flexible aliphatic dicarboxylic acids (itaconic and succinic acids) is challenging due to their insolubility, the related homophtalate compound readily forms a molecular tetranuclear cluster, [([(O2CCH2C6H4CO2)(μ-AlMe2)2]2. The molecular and crystal structures of the resulting compounds were determined via NMR spectroscopic analysis and single crystal X-ray diffraction crystallography.

High-Entropy Metal-Organic Frameworks (HEMOFs): A New Frontier in Materials Design for CO2 Utilization.

High-entropy materials (HEMs) emerged as promising candidates for a diverse array of chemical transformations, including CO2 utilization. However, traditional HEMs catalysts are nonporous, limiting their activity to surface sites. Designing HEMs with intrinsic porosity can open the door toward enhanced reactivity while maintaining the many benefits of high configurational entropy. Here, a synergistic experimental, analytical, and theoretical approach to design the first high-entropy metal-organic frameworks (HEMOFs) derived from polynuclear metal clusters is implemented, a novel class of porous HEMs that is highly active for CO2 fixation under mild conditions and short reaction times, outperforming existing heterogeneous catalysts. HEMOFs with up to 15 distinct metals are synthesized (the highest number of metals ever incorporated into a single MOF) and, for the first time, homogenous metal mixing within individual clusters is directly observed via high-resolution scanning transmission electron microscopy. Importantly, density functional theory studies provide unprecedented insight into the electronic structures of HEMOFs, demonstrating that the density of states in heterometallic clusters is highly sensitive to metal composition. This work dramatically advances HEMOF materials design, paving the way for further exploration of HEMs and offers new avenues for the development of multifunctional materials with tailored properties for a wide range of applications.

Nickel silicate CHA-type zeolite prepared by interzeolite transformation and its catalytic activity in dry reforming of methane

We newly synthesized the nickel silicate CHA-type zeolitic material (Ni-CHA) through the interzeolite transformation of the parent nickel silicate MWW-type zeolite (Ni-MWW) using the structure-directing ability of N,N,N-trimethyl-1-adamantammonium hydroxide. With increasing crystallization time under hydrothermal conditions, the parent Ni-MWW was decomposed into an X-ray amorphized nickel silicate, which was then consecutively reassembled into Ni-CHA. Furthermore, as the crystallization progressed, the framework Ni species gradually transformed from intermediate Ni to isolated Ni species, achieving a more thermodynamically stable chemical state. The metallic Ni clusters can be formed by exsolving from the CHA framework during the high-temperature reduction treatment, which were mainly distributed on the external surface. A series of in-situ reduced Ni-CHA-x catalysts obtained after different crystallization times (x = 0–72 h) were applied to the dry reforming of methane to evaluate their catalytic activity corresponding to the differences in crystallinity and chemical state. As a result, the interzeolite transformed Ni-CHA-72 h catalyst exhibited the highest catalytic performance even compared to the Ni-impregnated commercial SSZ-13.

C60 Fullerene-Induced Reduction of Metal Ions: Synthesis of C60-Metal Cluster Heterostructures with High Electrocatalytic Hydrogen-Evolution Performance.

Metal clusters, due to their small dimensions, contain a high proportion of surface atoms, thus possessing a significantly improved catalytic activity compared with their bulk counterparts and nanoparticles. Defective and modified carbon supports are effective in stabilizing metal clusters, however, the synthesis of isolated metal clusters still requires multiple steps and harsh conditions. Herein, we develop a C60 fullerene-driven spontaneous metal deposition process, where C60 serves as both a reductant and an anchor, to achieve uniform metal (Rh, Ir, Pt, Pd, Au and Ru) clusters without the need for any defects or functional groups on C60. Density functional theory calculations reveal that C60 possesses multiple strong metal adsorption sites, which favors stable and uniform deposition of metal atoms. In addition, owing to the electron-withdrawing properties of C60, the electronic structures of metal clusters are effectively regulated, not only optimizing the adsorption behavior of reaction intermediates but also accelerating the kinetics of hydrogen evolution reaction. The synthesized Ru/C60-300 exhibits remarkable performance for hydrogen evolution in an alkaline condition. This study demonstrates a facile and efficient method for synthesizing effective fullerene-supported metal cluster catalysts without any pretreatment and additional reducing agent.

Glue in hadrons at medium resolution and the QCD instanton vacuum

We discuss a general framework for the evaluation of the gluonic form factors in light hadrons at low momentum transfer, in the QCD instanton vacuum. At medium resolution of the order of the inverse mean instanton size, the glue is mostly localized in single or pairs of pseudoparticles and globally constrained by the fluctuations of their topological charges. These pseudoparticles trap light quarks, giving rise to emerging multiflavor ’t Hooft interactions. We explicitly evaluate the gluonic scalar, pseudoscalar, energy-momentum tensor (EMT), and the leading C-odd and C-even three-gluon hadronic form factors, at next to leading order in the instanton density, including molecular clusters of like and unlike instantons. We use the results for the EMT to address the contribution of the gluons in Ji’s mass and spin sum rules, at low resolution. When evolved, our results for the mass and spin composition of the nucleon are shown to be in good agreement with the recently reported lattice results at higher resolution. Published by the American Physical Society 2024

Boosting the Stability of Subnanometer Pt Catalysts by the Presence of Framework Indium(III) Sites in Zeolite

AbstractSubnanometer metal clusters show advantages over conventional metal nanoparticles in numerous catalytic reactions owing to their high percentage of exposed surface sites, abundance of under‐coordinated metal sites and unique electronic structures. However, the applications of subnanometer metal clusters in high‐temperature catalytic reactions (>600 °C) are still hindered, because of their low stability under harsh reaction conditions. In this work, we have developed a zeolite‐confined bimetallic PtIn catalyst with exceptionally high stability against sintering. A combination of experimental and theoretical studies shows that the isolated framework In(III) species serve as the anchoring sites for Pt species, precluding the migration and sintering of Pt species in the oxidative atmosphere at ≥650 °C. The catalyst comprising subnanometer PtIn clusters exhibits long‐term stability of >1000 h during a cyclic reaction‐regeneration test for ethane dehydrogenation reaction.

Boosting the Stability of Subnanometer Pt Catalysts by the Presence of Framework Indium(III) Sites in Zeolite.

Subnanometer metal clusters show advantages over conventional metal nanoparticles in numerous catalytic reactions owing to their high percentage of exposed surface sites, abundance of under-coordinated metal sites and unique electronic structures. However, the applications of subnanometer metal clusters in high-temperature catalytic reactions (>600 °C) are still hindered, because of their low stability under harsh reaction conditions. In this work, we have developed a zeolite-confined bimetallic PtIn catalyst with exceptionally high stability against sintering. A combination of experimental and theoretical studies shows that the isolated framework In(III) species serve as the anchoring sites for Pt species, precluding the migration and sintering of Pt species in the oxidative atmosphere at ≥650 °C. The catalyst comprising subnanometer PtIn clusters exhibits long-term stability of >1000 h during a cyclic reaction-regeneration test for ethane dehydrogenation reaction.

Beyond The Sphere. Au20(PR3)8 as a Spherical Aromatic Cuboctahedron Cluster.

The icosahedral Au135+ core is a recurrent building block in ligand-protected gold clusters involving an 8-cluster electron 1S21P6 electronic shell. Such a prototypical structure enables a spherical aromatic behavior as given by long-range magnetic shielding. Recently, the Au20(tBu3P)8 cluster featuring a contrasting cuboctahedral core with formally neutral gold atoms appears as a novel core architecture with the potential to be considered as another potential building block towards functional nanostructures. Here, we explore the ligand-core interaction and spherical aromatic characteristics of Au20(tBu3P)8, in order to provide a direct connection to classical icosahedral spherical aromatic compounds, now involving a cuboctahedral core structure. Such characteristics suggest rationalization of their robustness in terms of certain electron counts, enabling a shielding cone property in ligand-protected metallic clusters, which favors bridging organic and inorganic planar/spherical aromatic species towards the unification of the aromaticity concept and designing guidelines for further achievements.

Boosting hydrogenation properties of supported Cu-based catalysts by replacing Cu0 active sites

Balancing the Cu+/Cu0 ratio is a common strategy to improve catalytic activity of Cu-based catalysts but is still constrained by low atomic utilization and the inherent nature of charge distribution. Herein, we reported a strategy of replacing the Cu0 active sites in Cu-based catalysts by constructing bimetallic sites on ceria, which consist of spatially separated trace amounts of palladium metal and plate-shaped Cu+ clusters with one-atom layers. The catalytic activity of the prepared Cu100Pd1/CeO2-FA catalyst (using formic acid) was 4 times that of conventional Cu100Pd1/CeO2-H catalyst in selective hydrogenation of 5-hydroxymethylfurfural to 2,5-bis(hydroxymethyl)furan, even outperforming some existing noble metal catalysts. Multiple characterizations and theoretical calculations demonstrated that the Pd atom is the heterolytic activation site for H2 molecules while plate-shaped Cu+ metal clusters act as effective hydrogenation places. This directional control involving both spatial relationship and electronic structure of the active site provides a new strategy for designing hydrogenated catalysts.

Accelerating Relativistic Exact-Two-Component Density Functional Theory Calculations with Graphical Processing Units.

Numerical integration of the exchange-correlation potential is an inherently parallel problem that can be significantly accelerated by graphical processing units (GPUs). In this Letter, we present the first implementation of GPU-accelerated exchange-correlation potential in the GauXC library for relativistic, 2-component density functional theory. By benchmarking against copper, silver, and gold coinage metal clusters, we demonstrate the speed and efficiency of our implementation, achieving significant speedup compared to CPU-based calculations. One GPU card provides computational power equivalent to roughly 400 CPU cores in the context of this work. The speedup further increases for larger systems, highlighting the potential of our approach for future, more computationally demanding simulations. Our implementation supports arbitrary angular momentum basis functions, enabling the simulation of systems with heavy elements and providing substantial speedup to relativistic electronic structure calculations. This advancement paves the way for more efficient and extensive computational studies in the field of density functional theory.

A machine learning potential construction based on radial distribution function sampling.

Sampling reference data is crucial in machine learning potential (MLP) construction. Inadequate coverage of local configurations in reference data may lead to unphysical behaviors in MLP-based molecular dynamics (MLP-MD) simulations. To address this problem, this study proposes a new on-the-fly reference data sampling method called radial distribution function (RDF)-based data sampling for MLP construction. This method detects and extracts anomalous structures from the trajectories of MLP-MD simulations by focusing on the shapes of RDFs. The detected structures are added to the reference data to improve the accuracy of the MLP. This method allows us to realize a reasonable MLP construction for liquid water with minimal additional data. We prepare data from an H2O molecular cluster system and verify whether the constructed MLPs are practical for bulk water systems. MLP-MD simulations without RDF-based data sampling show unphysical behaviors, such as atomic collisions. In contrast, after applying this method, we obtain MLP-MD trajectories with features, such as RDF shapes and angle distributions, that are comparable to those of ab initio MD simulations. Our simulation results demonstrate that the RDF-based data sampling approach is useful for constructing MLPs that are robust to extrapolations from molecular cluster systems to bulk systems without any specialized know-how.

Manipulating the Substituent Sphere of a Bicyclic Silicon(I) Ring Compound Results in Anionic Cubane-Type Clusters and a Tetrahedral Silanide.

The reaction of the bicyclic silicon(I) ring compound Si4{N(SiMe3)Mes}4 1 with strong zwitterionic character and moderate sterical demand of the amido substituents with two equivalents of KC8 was investigated. This resulted in the unexpected abstraction of two amido substituents from 1 and additionally in dimerization to a dianionic Si8 cluster compound 2 with four unsubstituted silicon atoms and two [K([18]crown-6)]+ counter cations. Performing this reaction in the absence of [18]crown-6 results in release of only one amido substituent from 1 and dimerization to a dianionic Si8 cluster compound 3 with only two unsubstituted silicon atoms. This reaction with KC8 was repeated and trapping agents such as SiMe3Cl and tBuCl were added in-situ whereupon the second isolated homocyclic silylene 4 and a monoanionic hydride and tBu substituted Si8 cluster 5 with one unsubstituted silicon atom were isolated. Furthermore, 1 was reacted with KOtBu which resulted in the selective abstraction of one SiMe3 group and formation of the tetrahedral silanide 6 with one imido substituent bridging an edge of the tetrahedron.

Fullerene Derivatives for Tumor Treatment: Mechanisms and Application.

Fullerenes hold tremendous potential as alternatives to conventional chemotherapy or radiotherapy for tumor treatment due to their abilities to photodynamically kill tumor cells, destroy the tumor vasculature, inhibit tumor metastasis and activate anti-tumor immune responses, while protecting normal tissue through antioxidative effects. The symmetrical hollow molecular structures of fullerenes with abundant C=C bonds allow versatile chemical modification with diverse functional groups, metal clusters and biomacromolecules to synthesize a wide range of fullerene derivatives with increased water solubility, improved biocompatibility, enhanced photodynamic properties and stronger targeting abilities. This review introduces the anti-tumor mechanisms of fullerenes and summarizes the most recent works on the functionalization of fullerenes and the application of fullerene derivatives in tumor treatment. This review aims to serve as a valuable reference for further development and clinical application of anti-tumor fullerene derivatives.