Browse Articles

Association of the red blood cell distribution width-to-albumin ratio with subsequent cognitive impairment and adverse cognitive trajectories in older adults

Abstract The red blood cell distribution width-to-albumin ratio (RAR) is an index reflecting inflammatory and nutritional status. While prior studies reported cross-sectional associations between RAR and cognitive performance, its link to future cognitive outcomes has yet to be determined. Our research assessed the longitudinal associations of baseline RAR with subsequent incidence of cognitive impairment and with multi-year trajectories of cognitive change. This longitudinal cohort study included 5896 participants aged over 60 years from the Health and Retirement Study. During a 6-year follow-up, baseline RAR was examined in relation to incident cognitive impairment and membership in distinct cognitive trajectories identified with group-based trajectory modeling. Associations were assessed using multivariable Cox and logistic regression after adjustment. Restricted cubic splines (RCS) were also used to examine dose-response relationships, and we conducted sensitivity analyses to evaluate the stability of findings. During Follow-up, we identified 1586 incident cases of cognitive impairment and three distinct cognitive trajectories: High-stable (40.47%), Middle-slow decline (43.14%), and Low-rapid decline (16.39%). After full adjustment, one unit increase in baseline RAR was linked to a 18% higher incidence of cognitive impairment (HR = 1.18; 95% CI 1.06–1.31), and RCS analysis indicated the association to be linear ( P for non-linearity = 0.851). An elevated baseline RAR was also associated with a greater likelihood of membership in the Middle-slow decline (OR = 1.22; 95% CI 1.06–1.40) and Low-rapid decline (OR = 1.27; 95% CI 1.05–1.52) groups, relative to the High-stable group. In addition, these associations were consistent across all examined subgroups (all P  > 0.05) and remained robust in sensitivity analyses. Within this study population, a higher RAR was associated with increased risk of cognitive impairment and membership in unfavorable cognitive trajectories. RAR therefore warrants further investigation as a potential indicator of susceptibility to long-term cognitive decline.

Reaction Medium as an Architect of Nanocrystal Superlattices

Abstract Nanocrystal superlattices are commonly formed by changing concentration, solvent conditions, or particle surface chemistry. Although effective, these approaches alter multiple contributions to the interparticle potential simultaneously, making it difficult to isolate the interactions responsible for ordering or to control assembly in chemically complex environments. Here, we show that oligomeric species present in a nanocrystal reaction medium drive superlattice formation through a depletion mechanism. Using PbTe nanocrystals as a model system, we identify Pb–oleate oligomers in the crude reaction mixture, characterize their solution structure, and quantify their contribution to the interparticle potential, establishing depletion as the dominant short-range interaction governing spontaneous body-centered cubic superlattice formation. We then confirm the depletion origin of ordering by showing that varying depletant concentration predictably shifts the order–disorder boundary and produces a thermally reversible transition between dispersed and ordered states ─ behavior that is inconsistent with van der Waals or ligand-mediated mechanisms but is a direct consequence of depletion control. Having established and validated the mechanism, we demonstrate that the same depletion framework can be deliberately activated in purified dispersions and transferred across nanocrystal systems of different composition and shape, including anisotropic and binary assemblies. These results establish precursor-derived depletion as a general and chemically grounded mechanism for nanocrystal superlattice formation, and show that collective ordering can be programmed through the surrounding medium rather than through particle surface modification.

Correction: Fabrication of atomically flat cleavage planes with ultrafast laser scribing

Impact of urban air ultrafine particles on embryonic development and their association to transport emissions

Abstract Airborne ultrafine particles (UFP) constitute a potential risk factor for human health, being transport one of the most relevant sources, particularly in urban environments. We collected UFP from outdoor sites in Barcelona and Valencia (Spain) that were differently impacted by air pollution from road traffic, trains, ships, or planes. Zebrafish embryos were exposed to organic extracts from collection filters, and their transcriptomes were analysed by RNA deep sequencing. Functional analysis of 2,941 significantly affected transcripts revealed a strong enrichment in functions related to general embryotoxicity, like induction of degradation pathways (endocytosis, necroptosis), and inhibition of development- and cell division-related genes. This embryotoxicity-related transcriptional response was linked to samples exhibiting elevated concentrations of UFP and several inorganic and organic pollutants. It was particularly strong in airport samples, which were relatively poor on aromatic polycyclic hydrocarbons (PAHs). The functional analysis also identified a relatively small subset of genes configuring a typical dioxin-like response linked to PAH-rich emissions from harbour and traffic samples. Our findings indicate that the parameters currently used to assess air quality overlook the contribution of UFP and other non-regulated pollutants in the total airborne toxicity and, therefore, they do not adequately protect human populations.

Ultrabright Near-Infrared Lead-Free Perovskite Light-Emitting Diodes with Negligible Efficiency Roll-Off

Abstract Lead-free halide perovskite semiconductors show great promise for light-emitting diodes (LEDs), benefiting from tunable optoelectronic properties and solution processability. However, their practical applications in high-current-density LEDs are fundamentally constrained by severe efficiency roll-off, primarily caused by nonradiative recombination and carrier-induced structural instabilities. In this study, we introduce a molecular N,N′-diphenylthiourea (DPTA)-engineered tin perovskite semiconductor (CsSnI3) that achieves a photoluminescence quantum efficiency (PLQE) of 36% at a carrier concentration of 1018 cm–3. Our approach enables precise control over the charge-carrier concentration and lattice growth. High-resolution transmission electron microscopy further demonstrates that the uniform local strain distribution in the doped films enhances carrier wave-function overlap, leading to a substantial boost in PLQE. Leveraging the enhanced optoelectronic properties of DPTA-treated CsSnI3, we fabricate near-infrared LEDs that exhibit an external quantum efficiency (EQE) of 13.4% and an unprecedented peak radiance of 1248 W sr–1 m–2, with minimal efficiency roll-off even at high current densities exceeding 3500 mA cm–2 in pulse-mode operation. This work introduces a new material-doping strategy for lead-free perovskites, demonstrating their potential for high-power optoelectronic applications and advancing the feasibility of electrically pumped perovskite laser diodes.

Circulating SDF4 as a potential diagnostic marker for early-stage pancreatic cancer

Highly Dynamic Yet Stable Polyketimine Networks with Closed-Loop Recyclability and Topological Programmability

Abstract Closed-loop recycling via depolymerization has emerged as a promising strategy to mitigate plastic pollution. Ideal recyclable polymer networks should feature highly dynamic bonds that depolymerize efficiently into monomers/oligomers. However, this intrinsic bond lability inevitably introduces a critical trade-off, as it typically undermines the material’s stability. In this work, we design a polyketimine network that can be closed-loop recycled under mild conditions, without the need for consumable reagents or catalysts, while retaining robust mechanical properties during use. At the molecular level, hindered ketimine bonds remain sufficiently labile to depolymerize back to the designed oligomers, due to the steric hindrance from the ketone and amine reactants. At the network level, however, hydrophobic phases block water ingress, effectively “locking” the network and preserving mechanical performance even under harsh conditions (85 °C, 85% relative humidity, 48 h). When recycling is desired, a compatible organic solvent disrupts these hydrophobic phases, allowing water to penetrate the network and trigger depolymerization. Consequently, depolymerization and repolymerization cycles can be conducted using only easily recoverable water and solvents under mild conditions. By leveraging this dynamic chemistry, the synthesized polymers can be disassembled and reassembled into diverse network topologies, corresponding to a Young’s modulus that spans 6 orders of magnitude. Our work demonstrates that intrinsically labile dynamic bonds can be harnessed to build stable materials with tunable properties, offering a versatile platform for next-generation closed-loop recyclable polymers.

Molecular dynamics simulation of polymer-ceramic composites for the prediction of mechanical properties by investigating the role of binders in 3D printing applications

Experimental investigation and RSM optimization of performance and emissions in a diesel engine fueled with nitromethane/n-Butanol-diesel blends with exhaust gas recirculation

Abstract This paper presents the experimental study to evaluate the effect of adding the nitromethane (NM) with 20% n-butanol-diesel blend (B20) on the performance and emission characteristics of a EGR (exhaust gas recirculation) enabled diesel engine. The prime objective was to determine the optimum NM concentration and EGR rate that would enable effective control of exhaust smoke and NOx emissions with reasonable engine performance. The experiments were conducted on a vertical, single-cylinder, four-stroke, water-cooled, constant speed, direct injection diesel engine. NM was mixed with B20 at a ratio of 1% to 3% by volume, while the EGR rate was varied from 10% to 30%. A systematic experimental design was developed using Design Expert software to analyse the mutual effects of NM blending in fuel and application of EGR on engine responses. The analysis shows that the engine exhibited optimum results of performance and emissions with 2% NM added in 20% butanol-diesel blend(B20) combined with 15% EGR (B20NM2EGR15) under higher engine loading. For the derived optimized condition, smoke emissions were reduced by 64.45% and 32.14%, while NO x emissions declined by 25% and 17.18% as compared to diesel and B20, respectively. The brake thermal efficiency (BTE) for the optimized blend increased by 14.7% and 2.22% as compared to diesel and B20 respectively. Counter side, for B20NM2EGR15 the brake specific fuel consumption (BSFC) increased by 10.5% and 8.4% as compared to diesel and B20 respectively. The results show that the combined use of NM and EGR is an effective way to control smoke & NOx simultaneously with reasonable engine performance and are promising towards future emission norms.

Effects of cognitive behavioral therapy for insomnia on sleep, diet quality, and meal timing in Lebanese adults: a pilot controlled trial

Chain Length Dependence of Chemically Controlled Reactions in Polymerization

Abstract Chemically controlled reactions in polymerization processes are traditionally assumed to have chain-length-independent rate coefficients. However, this work challenges that assumption by using multiscale modeling to demonstrate that chemically controlled polymer–polymer reactions can exhibit significant chain length effects. Taking reversible addition–fragmentation chain transfer (RAFT) polymerization as a case study, we compare the chain length convergence of the reaction entropy for two processes: the addition of a growing polymer radical to a simultaneously growing polymeric RAFT agent, and the analogous reaction involving a low molecular weight RAFT agent. While the latter reaches equilibrium within 10 monomer additions, the former shows delayed convergence, with effects persisting to degrees of polymerization (DP) of 100 or more. A similar trend was observed in the Diels–Alder step-growth polymerization, where rapid convergence occurred when one chain length was fixed and short, but markedly slower convergence was observed when both reacting chain lengths increased simultaneously. These results reveal that entropy contributions, which scale logarithmically with chain length, lead to significant chain length dependence in the equilibrium constants (Keq). Because these effects arise from fundamental entropic considerations rather than specific features of the reacting species, they are expected to manifest broadly in the kinetics and thermodynamics of other chemically controlled polymer–polymer reactions. Our findings provide a mechanistic basis for resolving discrepancies in experimental estimates of fragmentation rate coefficients, shedding light on debate surrounding rate retardation in RAFT systems. More broadly, this work underscores the importance of chain length effects in the kinetics and thermodynamics of chemically controlled polymer–polymer reactions.

First cosmic-ray muography of a crust-mantle transition zone

Abstract Studying ophiolitic crust–mantle boundaries provides key insights into oceanic lithosphere formation, yet their internal density structure remains poorly constrained due to a scale gap: laboratory measurements capture centimeter-scale densities, whereas geophysical techniques average properties over kilometers and lack intermediate-scale continuity. Here, we use cosmic-ray muography to provide spatially continuous density constraints over tens to hundreds of meters, bridging this gap. We present the first muographic imaging of the crust–mantle transition zone (Moho Transition Zone, MTZ) at Wadi Fizh in the northern Samail Ophiolite. A multi-wire-proportional-chamber-based muography system was operated for 171 days at a distance of 400 m, producing a density image with ~ 3.5 m resolution. The mean density of layered gabbros is 3.03 g cm -3 , while lower densities (2.72 g cm -3 ) are observed within the MTZ, consistent with enhanced alteration, and higher densities (3.38 g cm -3 ) in the lower section indicate peridotitic rocks beneath a thin gabbroic cover. These results indicate that the crust–mantle transition at Wadi Fizh is spatially heterogeneous rather than a simple gradual boundary. Thus, muography enables continuous, in situ mapping of density variations at intermediate scales and provides a valuable complementary approach for studying the structure and evolution of the oceanic lithosphere.

Retraction of “Nanoscale Covalent Organic Framework with Staggered Stacking of Phthalocyanines for Mitochondria-Targeted Photodynamic Therapy”

Enhancing Sb2Se3 thin-film solar cell efficiency via CuGaSe2 dual-absorber integration

Deactivating Emission in Azulene via Solvent-Induced (Anti)Aromaticity

Abstract Anti-Kasha emission is a coveted feature in optoelectronics, with promise in areas such as imaging, sensing, and the production of white-light LEDs via dual-photon emission. Despite being a rare feature in organic systems, anti-Kasha emission is readily observed in the deceptively simple molecule azulene, which possesses two bright singlet states in the UV–visible spectrum and readily emits from the S2 state. With dominant anti-Kasha emission and decades of synthetic study, azulene is a perfect candidate for novel material fabrication; however, large gaps persist in understanding the photophysics of even the simple parent compound. These range from competing, experimentally unverified models of azulene reactivity and aromaticity to the unexplained deactivation of anti-Kasha emission in a host of azulene derivatives. Herein, we use fluorescence and transient absorption spectroscopies to explore the detailed solvent dependence of azulene photophysics. We discover a tunable reduction in the S2 lifetime via weak complexation with aromatic solvents. Interestingly, our results are independent of polarity, highlighting the primacy of peripherally delocalized 10-π Hückel aromaticity over zwitterionic character. When the dipolar character is enhanced through chemical functionalization, we observe even greater sensitivity to solvent aromaticity and more rapid quenching, revealing the role of conical intersections in azulenes with zwitterionic excited states. Overall, this work provides essential mechanistic insight into the photophysics of azulene and reveals a simple new approach to control the excited-state aromaticity and anti-Kasha emission in this class of materials.

Symmetry-aware graph optimization for scalable multisource remote-sensing data-fusion networks

Abstract The multisource remote-sensing fusion can be used to complement LiDAR, Sentinel-1 synthetic aperture radar (SAR) and UAV imaging to enhance the spatial analysis. But it is a problem that for large multimodal datasets it is not cost effective to represent this data as a spatial-feature graph for fusion and distributed processing. In this work, a symmetry-aware graph optimization framework is proposed to eliminate redundant computation in the multisource remote-sensing data-fusion workflow. Registered remote-sensing units are depicted as graph nodes and spatial neighbouring and multimodal feature similarity are represented as graph edges. The ability to recognize structurally equivalent node groups by graph automorphism combined with a partitioning of the orbits enables optimization to be carried out on a reduced orbit graph rather than the node-level graph. The optimized orbit-level solution is then projected in the original graph. The framework was tested with the graph sizes ranging from 1,000 to 50,000 nodes measured. With 1,000 nodes, the execution time dropped from 12.5 s, which was obtained using conventional optimization, to 8.2 s, obtained using distributed optimization, to 5.1 s. For 50,000 nodes, execution time decreased from 890.4 s to 520.8 s to 245.3 s, respectively. It is observed from these results that the reduction of graph based on the symmetry property enhances the computational scalability for large spatial-feature graph employed in the multisource remote-sensing fusion pipelines.

Perthionitrite-Induced Persulfidation in Binuclear Cobalt(II) Complexes

Abstract Persulfidation of sulfhydryl functional group (-SH) in protein and nonprotein thiols is a physiologically important process and generally involves the reduction of a partially oxidized sulfur by a fully reduced sulfur. In the present work, two dicobalt(II)-nitrito complexes, [Co2(PhBIMP)(μ-NO2)(DMF)]2+ (2) and [Co2(PhBIMP)(μ-NO2)2]1+ (3), have been demonstrated to react with RC(O)SH (R = Me, Ph) to generate the persulfidated complexes, [Co2(PhBIMP)(μ-SSC(O)R)]2+ (R = Me, 5a; Ph, 5b) in high yields (65–72%) along with nitric oxide (71–80%). Characterization of all the products and intermediates by structural and spectroscopic methods, and comparison of the results with those obtained from control experiments, established the generation of [Co2(PhBIMP)(μ-SC(O)R)(MeCN)]2+ (R = Me, 4a; Ph, 4b) and perthionitrite (SSNO–) in the reactions of 2/3 with RC(O)SH, followed by persulfidation of the coordinated thiocarboxylate (RC(O)S–) in 4a and 4b by the in situ generated SSNO– to produce the persulfidated complexes, 5a and 5b, respectively. The present work thus demonstrates, for the first time, that SSNO–, a physiologically relevant S/N-crosstalk species, can effectively mediate the persulfidation of sulfhydryl functional groups and may implicate a similar, but hitherto unknown, role of SSNO– in biological persulfidation processes.

Variations in regional assessment strategies for coastal flooding in the U.S. east and gulf coasts

Cycloparaphenylene-Derived Porous Organic Cylinders

Abstract Cycloparaphenylenes, with their distinctive radial conjugation and high macrocyclic rigidity, hold significant yet underexplored potential for the development of novel porous structures. We report the rational design and facile synthesis of three porous organic cylinders (POCys). Through dynamic boronate ester linkages, the coaxial covalent assembly of two catechol-functionalized cycloparaphenylenes could generate cylindrical scaffolds featuring large intrinsic cavities with interconnected channel networks. One of the POCys exhibits high porosity, showing a Brunauer–Emmett–Teller surface area of 1241 m2·g–1 and excellent gas adsorption capability. This work demonstrates the promise of cycloparaphenylene derivatives as a molecular platform for designing functional porous organic architectures.

The tRNA methylation activity and specificity of NSUN2 are independent of Archease

Abstract Transfer RNAs (tRNAs) undergo extensive maturation, including modifications essential for translation efficiency and fidelity, as well as for structural stability. The modification cytosine-5 methylation (m 5 C) is catalyzed by NSUN2 at multiple positions within distinct structural regions of a subset of tRNAs, yet the determinants of its substrate specificity remain elusive. In archaea, the protein Archease has been implicated in modulating the cytosine specificity of the NSUN2 ortholog Trm4, whereas mammalian Archease was shown to be involved in pre-tRNA splicing. Here, we investigated whether mammalian Archease influences NSUN2 in a similar way like the archaeal enzyme. Using short hairpin RNA-mediated depletion of Archease in mouse embryonic stem cells and in vitro methylation assays with recombinant proteins, we assessed both the catalytic activity and substrate selectivity of NSUN2 in the presence or the absence of Archease. Our results indicate that neither the efficiency nor positional specificity of NSUN2-mediated tRNA m 5 C methylation is affected by Archease. These findings indicate that, unlike in archaea, Archease does not regulate tRNA methylation by NSUN2 in mammals, highlighting an evolutionary divergence in the functional role of Archease in tRNA maturation pathways.