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Engineered nitrogen enriched magnetic biochar for enhanced adsorption of rhodamine 6G: a comparative study

Dedioxygenative Phosphonylation of Carboxylic Acids

Abstract Dedioxygenative transformations of carboxylic acids are faced with the significant challenges in efficiently breaking multiple C–O bonds and achieving broad applicability across diverse carboxylic acids, thereby hampering the development and application of this field. In this work, through the cooperation of multiple catalysts, we realized a dedioxygenative phosphonylation of carboxylic acids that is applicable to both aliphatic and aromatic substrates, showing good scope and functional-group tolerance. This protocol also demonstrates promising performance in the late-stage modification of complex molecules. Meanwhile, it establishes a formal deoxygenative coupling approach that enables rapid access to alkenes from carboxylic acids and aldehydes or alcohols. Mechanistic studies reveal distinct activation modes for different C–O bonds and further highlight a carbon-retentive transformation pattern of carboxylic acids, complementing conventional carbon-deletion decarboxylative phosphonylation based on redox-active esters or other strategies.

Unstable trunk core strength training improves shooting performance and holding stability in elite 10 m air pistol athletes: a pilot randomized controlled trial

Origins of Reactivity in SAM-Utilizing Ribozyme SAMURI-Catalyzed RNA Alkylation

Abstract Unlocking the design principles of programmable RNA catalysts capable of site-specific chemical modification is critical for expanding the functional and therapeutic potential of RNA. The SAM analogue-utilizing ribozyme (SAMURI) enables site-specific RNA alkylation using either S-adenosylmethionine (SAM) or the synthetic cofactor propargylic Se-2,6-diaminopurinribosyl-selenomethionineamide (ProSeDMA), yet the molecular determinants of its reactivity remain incompletely understood. Here, we combined molecular dynamics, 3D-RISM solvation analysis, alchemical free energy calculations, quantum pKa shift predictions, and ab initio QM/MM free energy simulations to characterize the conformational and electronic factors that govern catalysis. Simulations show that, although the global fold of SAMURI remains stable in solution, the formation of catalytically competent near-attack configurations is rare, indicating that the observed rate depends on access to a minor fraction of these reactive conformations (freact). A putative Mg2+ binding site between the SAM carboxylate and the G30 phosphate, together with a hydrogen bond between the cofactor α-amine and U8:O2, enriches freact. QM/MM simulations support an SN2-like alkyl transfer mechanism and show that ProSeDMA reacts more readily than SAM primarily due to its more favorable electronic leaving group properties that enhance the intrinsic rate (kint). Atomic substitutions at A52 that tune the N3 pKa enhance nucleophilicity, further lower the activation barrier, and increase kint. Together, these results show that SAMURI catalysis is governed by a combination of conformational preorganization and electronic effects, providing a framework to guide the design of new programmable RNA alkyltransferases.

Development and validation of the comprehensive mentalizing questionnaire

High-Pressure Investigation of the I–N System: Discovery of the Nitric Ozonide [N3]3– (“Ozonitride”) Species and Multicenter Bonding in Iodine Frameworks

Abstract Despite binary nitrides being heavily investigated at high pressures in the past decade, nitrogen halides are still a terra incognita at pressures exceeding 1 bar. Due to the unique chemistry of halogens, they are fertile grounds for the discovery of novel nitrogen species. Here, we report the high-pressure investigation of the I–N system up to 120 GPa using laser-heated diamond anvil cells and the synthesis of the first two thermodynamically stable binary iodine–nitrogen compounds, I4(N2)3 and I2(N2)(N3), formed from 81 and 95 GPa, respectively. Their crystal structures were solved and refined through synchrotron single-crystal X-ray diffraction measurements. I4(N2)3 is comprised of a layered polymeric iodine framework of hexagonal iodine units and infinite linear iodine chains─both evidenced to feature multicenter bonding─along with N2 dimers. In contrast, I2(N2)(N3) exhibits corrugated and distorted I6 layers along with N2 dimers as well as a hitherto unknown nitrogen species, [N3]3–. This anion is both isosteric and isoelectronic with ozone (O3), leading to its designation as a nitric ozonide (or “ozonitride” for simplicity). The stability domain of each compound is investigated, and their bulk modulus determined. Accompanying density functional theory calculations provide further insight into the crystal chemistry, stability regime, and physical properties of the two iodine–nitrogen compounds.

A loser-augmented duelist algorithm for cloud data center energy consumption minimization

Supramolecular Predisposition Promotes Intramolecular Heavy-Atom Effects for Self-Sensitized Oxidation

Abstract Supramolecular confinement is widely used to control molecular architecture, but its use to direct excited-state reaction pathways remains underexplored. This limitation is particularly evident for spin-forbidden processes such as intersystem crossing (ISC), which are difficult to regulate through supramolecular design. The heavy-atom effect, although central to promoting ISC, is typically regarded as an intrinsic substituent property rather than a geometry-dependent supramolecular parameter. Here we show that macrocycle-directed supramolecular predisposition can deliberately enforce intramolecular heavy-atom effects to activate latent spin-forbidden transitions, enabling efficient self-sensitized oxidation. Encapsulation of a flexible aldehyde- and bromine-substituted guest within cucurbit[8]uril (CB[8]) enforces a folded geometry that juxtaposes the heavy atom and reactive aldehyde, as established by solution studies and single-crystal analysis. Under white-light irradiation, this predisposed complex undergoes selective oxidation of the aldehyde to the corresponding carboxylic acid. Control experiments varying heavy-atom identity, cavity size, and guest binding modes define CB[8]-enforced spatial juxtaposition as the critical structural requirement, while scavenger and EPR studies support triplet-oxygen energy transfer to generate singlet oxygen as the operative pathway. Preferential binding of CB[8] to the substrate over the product mitigates product inhibition and allows catalytic turnover under substoichiometric host loadings. These results show that macrocyclic encapsulation does more than statically stabilize a host−guest complex: it transforms spatial geometry into a structurally gated switch for spin-forbidden pathways, establishing supramolecular predisposition as a versatile design principle for developing switchable photocatalysts and conformationally responsive smart materials.

Construction induced responses of the high speed railway subgrade to undercrossing by a large section mined metro tunnel

Spinterface-like Mechanism of the Chirality-Induced Spin Selectivity in Donor–Chiral Bridge–Acceptor Complexes

Abstract The chirality-induced spin selectivity (CISS) effect has been invoked to explain recent reports of differences in the time-resolved EPR signals between chiral and achiral molecules. However, the microscopic origin of these differences and their connection to CISS remain contested, particularly since these systems lack a metal interface. Here, we introduce an intramolecular spinterface-like mechanism that naturally arises within donor–chiral bridge–acceptor (D−χB–A) complexes and quantitatively reproduces experimentally reported observed spin polarization in time-resolved EPR studies. In our two-electron Lindblad model, the photoexcited charge-transfer electron traversing the chiral bridge exchanges with the residual donor electron, which acts as a localized magnetic moment analogous to an induced magnetic moment on an electrode surface. The resulting through-bridge charge current produces an effective solenoidal field at the donor–bridge interface, breaking spin degeneracy and directional symmetry, thus enabling spin-selective transport without invoking intrinsic spin–orbit coupling on the bridge. We show that the interplay among this current-induced field, donor thermalization (which breaks time-reversal symmetry), and bridge spin mixing yields tens-of-percent polarization over realistic experimental conditions and charge-transfer time scales, matching reported CISS signatures in triads and DNA hairpins. By explicitly resolving the dependence on solenoidal coupling strength, temperature, and spin-mixing rates, the model identifies the regime in which internal spinterfaces can generate robust CISS-like spin filtering. These findings demonstrate that CISS-like signals in isolated D−χB–A complexes are fully compatible with a spinterface mechanism, providing a unified conceptual framework for interpreting both device-based and molecule-internal CISS platforms.

Microstructure-driven description of drug release in tablets containing solid dispersions

Abstract In pharmaceutical formulations, the description or prediction of the final drug form (i.e. tablet) performance remains challenging when relying solely on material or process input parameters. Tablet microstructure analysis offers a beneficial alternative, particularly when solid dispersions are in the formulation. They provide a way to enhance drug bioavailability via partial or full amorphisation of the active substance (API) and stabilisation of the amorphous form. Moreover, they can have specific particulate properties that favour tablet performance description via microstructure (deformability due to higher amounts of polymer - especially in hot-melt extrudates). The purpose of this work was to apply an image-based method for tablet microstructure description to model systems containing solid dispersions. Two binary systems containing solid dispersion of API prepared via hot-melt extrusion and CaHPO 4 ∙2H 2 O were tested. One, containing API rivaroxaban, varying extrudate properties (particle size, plasticiser content) with fixed tablet composition, the second with fixed extrudate properties and variable composition containing API indomethacin. When tablet composition remained constant, extrudate characteristics dominated tablet performance description over tablet microstructure and porosity. With fixed extrudate properties, the application of the image-based microstructure evaluation method proved to be sensible and provided further insight into its application. For the tested combination of indomethacin-Kollidon VA64 extrudate with excipient CaHPO 4 ∙2H 2 O, the best description of dissolution properties was achieved using the d (10) values (excipient observable areas on tablet cross-sections). The obtained results extend the previously proposed microstructure-based approach for describing dissolution performance to solid-dispersion-based tablets, providing a more specialised possible model system.

Structural Chemistry of [V2As17]3– and [V2Sb17]4–: A Complex Interplay between V-Pn and Pn-Pn Bonding

Abstract The ability of the heavier pnictogen elements, P, As, Sb and Bi, to form extensively catenated structures is well established, and a wide range of architectures is known, both for the isolated ions and for their coordination complexes. In this work, we report two new vanadium clusters, [V2As17]3– and [V2Sb17]4–, which contain crown-like VPn8 units, linked by a single bridging atom. Reaction monitoring using ESI-MS suggests a growth pathway involving both VPn8 and VPn9 units, the latter appearing transiently in the reaction mixture. Density functional theory reveals that the redox-active orbital has Pn–Pn antibonding character: the two clusters can therefore be considered to map a segment of the potential energy surface linking the entirely separated fragments to a single fused Pn17 unit.

Reprogramming ThDP Enzymes for <i>Z</i> -Alkenes: Overriding Thermodynamic Preference via Noncovalent Controls

Abstract Most conventional alkene synthesis reactions (e.g., elimination et al.) inherently favor the formation of thermodynamically more stable E-isomers, posing a long-standing challenge for direct access to Z-alkenes. Here, we report the reprogramming of a thiamine diphosphate (ThDP)-dependent enzyme to catalyze a formal dehalogenative elimination that overrides this intrinsic thermodynamic bias, enabling the direct and selective synthesis of Z-α,β-unsaturated carboxylic acids. In contrast to classical approaches that rely on substrate control, directing groups, or complex ligand architectures, our strategy harnesses the enzyme’s confined active site to achieve kinetic control exclusively via noncovalent interactions─representing a fundamentally distinct and more sustainable approach to stereochemical programming. This transformation diverts the enzyme from its native function in C–C bond formation by channeling the Breslow intermediate toward a homoenolate-mediated pathway, wherein specific noncovalent interactions stabilize the syn-periplanar geometry required for Z-selective dehalogenative elimination. Through rational active-site engineering, the stereochemical trajectory can be inverted to furnish the complementary E-isomer, enabling stereodivergent synthesis from a common scaffold. This work establishes a biocatalytic platform that addresses a critical gap in Z-alkene synthesis, expands the catalytic repertoire of ThDP-dependent enzymes, and provides a sustainable alternative to conventional methodologies.

Dual bispecific protein engagers targeting mesothelin and NECTIN2 deliver CD3/CD28 signals to activate cytotoxic T cells against colorectal cancer patient-derived organoids

Pulse-Driven Paired Electrosynthesis of Formamide via Redox-Tuned Intermediate Management

Abstract Renewable electricity-driven electrocatalytic systems hold promise for the sustainable formamide (HCONH2) synthesis. However, a major bottleneck remains the low Faradaic efficiency (FE) and overall electron utilization inherent to current unipolar C–N coupling strategies, where substantial electron consumption at the counter electrode severely limits system efficiency. Here, we propose a redox-tuned paradigm (Ared+ Boxi→ C) through a pulsed paired electrosynthesis strategy. Using an atomically ordered CuPd catalyst with CH3OH and NO2– as feedstocks in an undivided cell, HCONH2 is simultaneously produced at both electrodes under optimized pulse conditions with alternating change in potential periodically (Ea = 1.3 V, ta = 10 s; Ec = −0.7 V, tc = 10 s). This system achieves an FE of 85.6% for HCONH2 at a current density of 81.5 mA cm–2, with a yield of 263.3 μmol·h–1·cm–2. The FE is higher than those reported to date. Mechanism studies reveal that pulsed operation creates a periodically switching cathode/anode environment. This enables the ordered CuPd catalyst to function sequentially as a reduction site (converting NO2– to *NH3) during cathodic pulses and as a co-oxidation site (converting *NH3 to *NH2 along with CH3OH to *HCOH) during anodic pulses, thereby driving efficient C–N bond coupling to form HCONH2. Techno-economic analysis further confirmed the significant industrial potential of this strategy in the future renewable energy market.

All-optical single-shot mapping of cluster radius and density in an axisymmetric gas jet

Abstract We demonstrate an all-optical, single-shot diagnostic enabling spatially resolved two-dimensional reconstruction of cluster radius and number density in a cryocooled deuterium jet. Conventional characterizations based on one-dimensional mechanical scanning or projection-only measurements obscure local heterogeneity and complicate quantitative interpretation of cluster formation and scaling. By combining Mach–Zehnder interferometry and Rayleigh scattering with Abel-based tomographic reconstruction, we retrieve local maps of cluster size and density across an extended cross section of the jet in a single acquisition. The measurements reveal that the cluster radius remains nearly uniform (~11 nm) within the jet interior despite pronounced radial and axial density gradients, indicating that nucleation is largely completed near the nozzle exit while subsequent expansion predominantly governs density evolution. This spatial decoupling between cluster size and density demonstrates that region-dependent averaging can substantially bias inferred scaling relations. The resulting scan-free tomographic framework establishes a physically consistent basis for analyzing nucleation and growth in cryogenic cluster jets and for quantitative, region-selective optimization in laser–plasma applications.

The sense of self shapes the impact of environmental factors on technostress and mental health: a two-wave longitudinal study

Efficient Synthesis of N-Bridged Annulenes

Abstract The most commonly encountered aromatic structure is the benzenoid ring, which is observed in a wide variety of pharmaceuticals and organic materials. However, studies on nonbenzenoid conjugated polyene aromatic molecules remain scarce, largely due to synthetic challenges and inherent angle strain. Herein, we report an unprecedented single-copper relay dual-catalyzed cascade sequence for the efficient construction of a unique aromatic N-bridged [10]annulene (NBA) framework (also called cycl[3,2,2]azine), in which a copper-catalyzed 10π electrocyclization is involved. To gain insight into the reaction mechanism, a series of control experiments and density functional theory calculations were conducted. The developed reaction exhibits broad functional-group tolerance and can be extended to different classes of 14π components. Significantly, the resulting NBA compounds display strong fluorescence with full-color tunability. Therefore, these innovations not only deepen our understanding of the aromaticity of nonbenzenoid systems but also highlight the potential of metal-catalyzed electrocyclization in synthetic chemistry.

A new hybrid uncertainty controlling framework for optimal scheduling of power-gas networks connected to industrial energy hubs considering hydrogen vehicles and flexibility resources

Identifying Disordered Intermediates in the Reaction of Cu3– <i>x</i> P and Dibenzyl Diselenide to form Cu3PSe4 Nanoparticles

Abstract Developing a detailed understanding of ternary nanoparticle (TNP) formation is essential for their optimized rational synthesis and development of synthetic routes for new TNPs. Herein, we explore the reaction of Cu3–xP and dibenzyl diselenide (Bn2Se2) to form colloidal Cu3PSe4 TNPs. Temperature-resolved X-ray scattering (XRD and PDF), electron microscopy (TEM and STEM), and spectroscopy (EDS, EELS, XPS, and MAS NMR) reveal that Cu3–xP reacts by surface coordination of Se leading to fragmentation followed by rearrangement to Cu–Se binary phases, during which all obvious crystalline P-containing phases disappear via XRD. However, partially oxidized P in solid phases was observed using STEM-EDS and XPS, in which P is found to preform P–Se bonds prior to Cu3PSe4 formation. Using a combination of 31P MAS NMR and PDF analysis obtained from synchrotron total scattering data, P–Se bonds in [PSe4]3– tetrahedral building blocks were identified within intermediate Cu–Se phases containing P cation substitution (PCu), denoted (Cu,P)–Se, that assemble into Cu3PSe4. We hypothesize that these intermediate compounds with their substoichiometric, vacancy-rich structures and significant Cu disorder are important for accessing Cu3PSe4─offering a new insight into complex TNP syntheses. We summarize our findings by writing plausible pseudoelementary steps (PESteps) in which the Cu3–xP precursor converts to smaller fragments of Cu–Se phases containing P en route to the final Cu3PSe4 product. Additional interesting aspects of this system include the use of Bn2Se2 as a readily monitorable probe for the reaction and the Se–P bond formation that facilitates Cu–P bond cleavage in an overall 8-electron redox reaction involving P3– and 4 Se0. The results obtained lay the groundwork for future mechanistic investigations, notably kinetics studies working from the PESteps aimed ultimately at the rational design and synthesis of complex ternary pnictogen chalcogenide nanoparticles.