A turn-on fluorescent probe containing a β-ketoester moiety for the selective detection of intracellular hydrazine.

Fluorogenic probes containing the β-ketoester structure were developed for selective hydrazine detection. The probe equipped with a cyclopropane moiety, having reduced steric hindrance, showed a higher reaction rate than its dimethyl counterpart. In live cell imaging, the probe detects intracellular hydrazine with minimal cytotoxicity.

Hysteresis in the transfer characteristics of MoS field effect transistors: gas, temperature and photo-irradiation effect.

We report the characteristic behaviors of the hysteresis observed in the transfer characteristics of back-gated field-effect transistors with an exfoliated MoS channel under various conditions. We find that the hysteresis is strongly enhanced by temperature, environmental gas, or light irradiation. Our measurements reveal the characteristic hysteresis behaviors in a 1 atm oxygen environment, which we explain as an oxygen molecule facilitated charge acceptor on the MoS surface.

Dynamic spin reordering in a hybrid layered ferrimagnet with intercalated biferrocenium radicals.

Molecule-based hybrid layered magnets provide an ideal platform for investigating the long-range spin-ordering process in low-dimensional magnetic systems. Within this context, a promising area of research is spin-sandwiched hybrid layered magnets. These materials offer the potential to explore how the spin, which is sandwiched between magnetic layers, is influenced by the internal magnetic fields generated by the magnetic layers.

CO-actuated spin transition tuning in an interdigitated Hofmann-type coordination polymer.

The increased anthropogenic emission level of CO urges the development of CO-responsive materials, but is it possible to regulate the inherent electronic properties through weak physisorption of a ubiquitous gas such as CO? Herein, we intended to answer this imperative question by the first case of CO-actuated variable spin-state stabilisation in an interdigitated Hofmann-type coordination polymer [FePd(CN)L] (1, L = methyl isonicotinate), showing a wide shift in transition temperature ( ) from 178 K at = 0 kPa to 229 K at = 100 kPa. Interestingly, the emergence of a stepped behaviour in the heating process below = 10 kPa and overlapping magnetic susceptibility values above = 10 kPa elucidate the selective LS state stabilisation solely correlated with the extent of CO accommodation. Based on the magnetic response and phase transition diagrams obtained under respective , a plausible scenario of the spin-state switching can be interpreted as (1 + ) → (1 + ) → 1 at ≤ 10 kPa, → 1 at 100 kPa < ≥ 32 kPa and → → 1 at 100 kPa, where 1 and 1' represent CO-free and CO-encapsulated states, respectively.

Targeted protein degradation in the mitochondrial matrix and its application to chemical control of mitochondrial morphology.

Dysfunction of mitochondria is implicated in various diseases, including cancer and neurodegenerative disorders, but drug discovery targeting mitochondria and mitochondrial proteins has so far made limited progress. Targeted protein degradation (TPD) technologies represented by proteolysis targeting chimeras (PROTACs) are potentially applicable for this purpose, but most existing TPD approaches leverage the ubiquitin-proteasome system or lysosomes, which are absent in mitochondria, and TPD in mitochondria (mitoTPD) remains little explored. Herein, we describe the design and synthesis of a bifunctional molecule comprising TR79, an activator of the mitochondrial protease complex caseinolytic protease P (ClpP), linked to desthiobiotin.

Unlocking the chemical environment of nitrogen in perovskite-type oxides.

Nitrogen (N) doping of perovskite-type oxides is an effective method for enhancing their photocatalytic performance. Quantitative and qualitative analyses of the doped N species are essential for a deeper understanding of the catalytic activity enhancement mechanism. However, examining the N environment in perovskite-type oxides, particularly in the bulk, using conventional analytical techniques, such as X-ray photoelectron spectroscopy (XPS), is challenging.

Modifications of the charge-discharge behaviour of Fe(MoO) in all-solid-state lithium-ion batteries.

The solidification of lithium-ion batteries (LIBs) by replacing liquid electrolytes with solid electrolytes enables the development of a new class of LIBs, namely all-solid-state lithium-ion batteries (ASSLIBs), with improved safety and energy density. Such battery solidification can greatly influence the properties of battery components, as exemplified by a recent report suggesting that the (dis)charge behaviour of Fe(MoO) (FMO), a promising two-phase electrode material, differs on solid electrolytes compared to liquid electrolytes. However, its underlying mechanism remains unclear.

Network topology diversification of porous organic salts.

Hydrogen-bonded organic frameworks (HOFs) are porous organic materials constructed hydrogen bonds. HOFs have solubility in specific high-polar organic solvents. Therefore, HOFs can be returned to their components and can be reconstructed, which indicates their high recyclability.

Conformer-Specific Photoelectron Spectroscopy of Carbonic Acid: HCO.

Carbonic acid (HCO) is a fundamental species in biological, ecological, and astronomical systems. However, its spectroscopic characterization is incomplete because of its reactive nature. The photoionization (PI) and the photoion mass-selected threshold photoelectron (ms-TPE) spectra of HCO were obtained by utilizing vacuum ultraviolet (VUV) synchrotron radiation and double imaging photoelectron photoion coincidence spectroscopy.

Helix-based screening with structure prediction using artificial intelligence has potential for the rapid development of peptide inhibitors targeting class I viral fusion.

The rapid development of drugs against emerging and re-emerging viruses is required to prevent future pandemics. However, inhibitors usually take a long time to optimize. Here, to improve the optimization step, we used two heptad repeats (HR) in the spike protein (S protein) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a model and established a screening system for peptide-based inhibitors containing an α-helix region (SPICA).

Toward three-dimensionally ordered nanoporous graphene materials: template synthesis, structure, and applications.

Precise template synthesis will realize three-dimensionally ordered nanoporous graphenes (NPGs) with a spatially controlled seamless graphene structure and fewer edges. These structural features result in superelastic nature, high electrochemical stability, high electrical conductivity, and fast diffusion of gases and ions at the same time. Such innovative 3D graphene materials are conducive to solving energy-related issues for a better future.

Atomic metal coordinated to nitrogen-doped carbon electrocatalysts for proton exchange membrane fuel cells: a perspective on progress, pitfalls and prospectives.

Proton exchange membrane fuel cells require reduced construction costs to improve commercial viability, which can be fueled by elimination of platinum as the O reduction electrocatalyst. The past 10 years has seen significant developments in synthesis, characterisation, and electrocatalytic performance of the most promising alternative electrocatalyst; single metal atoms coordinated to nitrogen-doped carbon (M-N-C). In this Perspective we recap some of the important achievements of M-N-Cs in the last decade, as well as discussing current knowledge gaps and future research directions for the community.

Functional connectivity between the amygdala and prefrontal cortex underlies processing of emotion ambiguity.

Processing facial expressions of emotion draws on a distributed brain network. In particular, judging ambiguous facial emotions involves coordination between multiple brain areas. Here, we applied multimodal functional connectivity analysis to achieve network-level understanding of the neural mechanisms underlying perceptual ambiguity in facial expressions.

Guest-induced pore breathing controls the spin state in a cyanido-bridged framework.

Iron(ii) spin cross-over (SCO) compounds combine a thermally driven transition from the diamagnetic low-spin (LS) state to the paramagnetic high-spin (HS) state with a distinct change in the crystal lattice volume. Inversely, if the crystal lattice volume was modulated post-synthetically, the spin state of the compound could be tunable, resulting in the inverse effect for SCO. Herein, we demonstrate such a spin-state tuning in a breathing cyanido-bridged porous coordination polymer (PCP), where the volume change resulting from guest-induced gate-opening and -closing directly affects its spin state.

Topological capture of mRNA for silencing gene expression.

We describe herein topological mRNA capture using branched oligodeoxynucleotides (ODNs) with multiple reactive functional groups. These fragmented ODNs efficiently formed topological complexes on template mRNA . In cell-based experiments targeting AcGFP mRNA, the bifurcated reactive ODNs showed a much larger gene silencing effect than the corresponding natural antisense ODN.

Photoion Mass-Selected Threshold Photoelectron Spectroscopy to Detect Reactive Intermediates in Catalysis: From Instrumentation and Examples to Peculiarities and a Database.

Photoion mass-selected threshold photoelectron spectroscopy (ms-TPES) is a synchrotron-based, universal, sensitive, and multiplexed detection tool applied in the areas of catalysis, combustion, and gas-phase reactions. Isomer-selective vibrational fingerprints in the ms-TPES of stable and reactive intermediates allow for unequivocal assignment of spectral carriers. Case studies are presented on heterogeneous catalysis, revealing the role of ketenes in the methanol-to-olefins process, the catalytic pyrolysis mechanism of lignin model compounds, and the radical chemistry upon C-H activation in oxyhalogenation.

Chemistry of zipping reactions in mesoporous carbon consisting of minimally stacked graphene layers.

The structural evolution of highly mesoporous templated carbons is examined from temperatures of 1173 to 2873 K to elucidate the optimal conditions for facilitating graphene-zipping reactions whilst minimizing graphene stacking processes. Mesoporous carbons comprising a few-layer graphene wall display excellent thermal stability up to 2073 K coupled with a nanoporous structure and three-dimensional framework. Nevertheless, advanced temperature-programmed desorption (TPD), X-ray diffraction, and Raman spectroscopy show graphene-zipping reactions occur at temperatures between 1173 and 1873 K.

Structural and molecular insight into antibody recognition of dynamic neoepitopes in membrane tethered MUC1 of pancreatic cancer cells and secreted exosomes.

Pancreatic cancer is highly metastatic and has poor prognosis, mainly due to delayed detection, often after metastasis has occurred. A novel method to enable early detection and disease intervention is strongly needed. Here we unveil for the first time that pancreatic cancer cells (PANC-1) and secreted exosomes express MUC1 bearing cancer-relevant dynamic epitopes recognized specifically by an anti-MUC1 antibody (SN-131), which binds specifically core 1 but not core 2 type -glycans found in normal cells.

Experimental probing of dynamic self-organized columnar assemblies in colloidal liquid crystals.

Self-organized supramolecular assemblies are widespread in nature and technology in the form of liquid crystals, colloids, and gels. The reversible nature of non-covalent bonding leads to dynamic functions such as stimuli-responsive switching and self-healing, which are unachievable from an isolated molecule. However, multiple intermolecular interactions generate diverse conformational and configurational molecular motions over various time scales in their self-assembled states, and their specific dynamics remains unclear.

Quantum structural fluxion in superconducting lanthanum polyhydride.

The discovery of 250-kelvin superconducting lanthanum polyhydride under high pressure marked a significant advance toward the realization of a room-temperature superconductor. X-ray diffraction (XRD) studies reveal a nonstoichiometric LaH or LaH polyhydride responsible for the superconductivity, which in the literature is commonly treated as LaH without accounting for stoichiometric defects. Here, we discover significant nuclear quantum effects (NQE) in this polyhydride, and demonstrate that a minor amount of stoichiometric defects will cause quantum proton diffusion in the otherwise rigid lanthanum lattice in the ground state.

Mechanisms of chemical-reaction-induced tensile deformation of an Fe/Ni/Cr alloy revealed by reactive atomistic simulations.

High entropy alloys (HEAs) have demonstrated excellent potential in various applications owing to the unique properties. One of the most critical issues of HEAs is the stress corrosion cracking (SCC) which limits its reliability in practical applications. However, the SCC mechanisms have not been fully understood yet because of the difficulty of experimental measuring of atomic-scale deformation mechanisms and surface reactions.

Magnesium oxide-water compounds at megabar pressure and implications on planetary interiors.

Magnesium Oxide (MgO) and water (HO) are abundant in the interior of planets. Their properties, and in particular their interaction, significantly affect the planet interior structure and thermal evolution. Here, using crystal structure predictions and ab initio molecular dynamics simulations, we find that MgO and HO can react again at ultrahigh pressure, although Mg(OH) decomposes at low pressure.

Inter-layer magnetic tuning by gas adsorption in π-stacked pillared-layer framework magnets.

Magnetism of layered magnets depends on the inter-layer through-space magnetic interactions ( ). Using guest sorption to address inter-layer pores in bulk-layered magnets is an efficient approach to magnetism control because the guest-delicate inter-layer distance ( ) is a variable parameter for modulating . Herein, we demonstrated magnetic changes induced by the adsorption of CO, N, and O gases in various isostructural layered magnets with a π-stacked pillared-layer framework, , (M = Co, 1, Fe, 2, Cr, 3; Cp* = η-CMe; 2,3,5,6-FPhCO = 2,3,5,6-tetrafluorobenzoate; TCNQ = 7,7,8,8-tetracyano--quinodimethane).

Selective and high-rate CO electroreduction by metal-doped covalent triazine frameworks: a computational and experimental hybrid approach.

The electrochemical CO reduction reaction (CORR) has attracted intensive attention as a technology to achieve a carbon-neutral society. The use of gas diffusion electrodes (GDEs) enables the realization of high-rate CORRs, which is one of the critical requirements for social implementation. Although both a high reaction rate and good selectivity are simultaneously required for electrocatalysts on GDEs, no systematic study of the relationship among active metal centers in electrocatalysts, reaction rate, and selectivity under high-rate CORR conditions has been reported.

Speciation of chromium aqua and chloro complexes in hydrochloric acid solutions at 298 K.

The distribution of metal aqua and chloro complexes is fundamental information for analysis of a chemical reaction involving these complexes. The present study investigated the speciation and structures of chromium aqua and chloro complexes using the thermodynamic model fitting analysis of UV-vis/X-ray absorption spectra. The existence of a negatively charged species was examined by adsorbability of chromium species on a strong base anion exchanger.