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Leveraging rpoB amplicon signals from Xpert MTB/RIF ultra as a diagnostic opportunity for identifying Non-tuberculous mycobacteria in TB-negative specimens
Radical‐Based On‐Surface Transformation of Nonplanar Aromatics Into Nonbenzenoid Nanographenes
ABSTRACT On‐surface synthesis has emerged as a powerful tool for atomically precise C─C bond formation, enabling access to low‐dimensional carbon‐based materials, often unattainable by conventional solution‐based chemistry. This approach gave rise to a novel class of magnetic materials, namely open‐shell magnetic nanographenes, whose magnetism originates primarily from unpaired electrons. Despite this progress, a fundamental understanding of selectivity and specificity of surface‐confined radical chemistry remains limited. Here, we demonstrate that nonplanar hydrocarbons such as helicenes undergo highly selective intramolecular radical‐driven bond formation and reorganization on an Au(111) surface, yielding nonbenzenoid nanographenes incorporating 5‐, 6‐, and 7‐membered rings. The products are identified using time‐of‐flight secondary ion mass spectrometry, scanning tunneling microscopy, and non‐contact atomic force microscopy, which collectively support a radical‐mediated cyclization pathway. The mechanism is distinct from the Diels–Alder cycloaddition and cyclodehydrogenation reactions previously reported for helicenes on surfaces.
Timber harvesting intensity and use of decision-support tools among semi-professional private forest owners: a Norwegian case study
Abstract Non-industrial private forest owners are known to have multiple ownership values and objectives. Their management decisions have multiple impacts on the supply of ecosystem services from forests. Forest management plans, a main decision-support tool for many forest owners, tend to be timber-oriented, potentially leading to more harvesting and more frequent use among production-oriented owners. We investigated factors explaining harvest intensity, measured as the ratio of property-level actual harvest volumes to predicted harvest volumes and the use of forest management plans among 119 semi-professional, non-industrial, private forest owners in Norway. Harvest intensity decreased with forest area and with biodiversity and nextgeneration’s need as ownership objectives and increased with wood prices and owner engagement but was not impacted by short-term profit or use of forest management plans. Use of forest management plans increased with forest area, having received instructions, trust in the harvest predictions, and economic ownership objectives. By using property-level harvest prediction, we could compare harvest figures to the actual timber resource, formed by each property’s forest biophysical attributes. This approach may be a valuable step in developing models that provide enhanced understanding of how forest owner behavior is shaped by preferences and objectives.
Fluorinative Rearrangement of Vinyl Diazo Compounds Enabled by a New Reactivity Mode of Cyclopropanediazonium Ions
ABSTRACT Although selective transformations of aromatic and purely aliphatic diazonium ions are well‐established, the reactivity of the unique cyclopropanediazonium (CPD) ions remains largely unexplored owing to their intrinsic instability. Herein, we report a new reaction mode of CPD ions mediated by hypervalent iodine reagents. The reaction enables a fluorinative 1,2‐diazo function migration of vinyl diazo compounds to afford synthetically useful but previously unavailable β,β‐difluorinated diazoester products. This transformation exhibits high efficiency, broad substrate scope, facile scalability, and complete chemo‐ and regioselectivity, alongside versatile downstream applications. Both control experiments and detailed DFT calculations suggest the formation of a key CPD ion intermediate that undergoes an unprecedented ring‐opening rearrangement of such species to furnish the product. Despite the pronounced complexity of the reaction pathway, which requires precise selectivity control at nearly every step, comprehensive computational analysis of a range of possible transition states elucidates the unusual reactivity and underlying origin of the observed selectivity.
Association of parental death and separation with child mortality in India
Probability characteristics and extreme value analysis of fluctuating wind pressure on heliostat arrays
Decoding Carbon Dot Purity by Nuclear Magnetic Resonance
ABSTRACT Carbon dots (CDs) have attracted increasing attention in recent years and have been widely explored in many fields. However, several challenges still limit their further development, particularly the unclear atomic structure and fluorescent mechanisms. Addressing these issues requires a thorough purification of crude CD products followed by reliable purity assessment. In this work, we combine dialysis and NMR analysis to evaluate the effectiveness of purification and consequent purity of CDs. Two representative CDs, citric acid‐ethylenediamine‐derived CDs and citric acid‐ p ‐phenylenediamine‐derived CDs were synthesized via hydrothermal treatments. The crude products were first filtered and aliquoted for dialysis. Collected retentates were characterized by microscopy and spectroscopy techniques. With increasing dialysis time, the mass of retentates gradually decreased reaching a steady state. In the NMR spectra, sharps peaks gradually attenuated and eventually disappeared, indicating progressive removal of impurities. Meanwhile, the ratio of integrated broad peaks to sharp peaks increased and reached a plateau with prolonged dialysis. A linear correlation was observed between CD purity and the integrated peak ratios. This work establishes a standardized and (semi‐)quantitative NMR‐based methodology for CD purity assessment, enabling a systematic differentiation and relative quantification of CDs and coexisting small molecular species, thereby addressing a key limitation of previous analyzes.
A user-friendly online tool for paleocoordinate calculation and 3D visualization
About the Role of Interfacial Lattice Oxygen in Pd─Pt Alloy for C─C Cleavage in Ethanol Electrooxidation
ABSTRACT The electrocatalytic ethanol oxidation reaction is bottlenecked by inefficient C─C bond cleavage. This challenge is epitomized at metal‐oxide heterointerfaces, where the active site identity and cleavage mechanism remain obscured. Here, we decoded this by atomically programming model PdO─Pt 3 Pd heterointerfaces. Through 18 O isotopic labeling, we identify the interfacial lattice oxygen (O Int ) in Pd 2+ ─O Int ─Pd alloy motif as the direct oxygen donor for C─C cleavage. The interfacial built‐in electric field activates O Int as a nucleophilic scalpel by upshifting its p‐band center, resulting in an ultralow cleavage barrier of 0.47 eV. Beyond a single site, we demonstrate that the interface functions as a reaction‐network architect. It creates a dominant O Int ‐mediated “non‐CO” C1 pathway at the PdO─Pt 3 Pd heterointerface while re‐engineering the traditional “CO” pathway on the adjacent Pt 3 Pd domain via threefold optimization: minimizing *CO source, suppressing acetate formation and ensuring rapid *CO removal. This dual‐path integration yields breakthrough performance with a mass activity of 9.09 A mg metal −1 and a C1‐pathway Faradaic efficiency of 75.6%. This work reports a paradigm shift from a passive “scavenger” model to an active “initial‐attack and system‐orchestration” mechanism, redefining heterointerfaces as atomically programmable reaction‐network architects. This paradigm offers a blueprint for mastering complex reaction networks, extending the frontier of rational catalyst design.
Determination of background concentrations and risk-screening values for elements in oasis soils in the arid zone of the Tibetan Plateau using multifractal models
Hexamethoxy Triazocoronene Based Covalent Organic Frameworks: A Family of Tailored Tools for Efficient Gold Recovery
ABSTRACT Covalent organic frameworks (COFs) have recently emerged huge prospects as new adsorption platforms for gold recovery, however, the design and construction of robust COFs with the superior capacity and kinetics is an urgent yet formidable challenge. Herein, three triazocoronene‐based COFs (COF‐JLU63–65) were synthesized for the first time via Schiff base polycondensation. The obtained materials combine high crystallinity, large surface area and abundant heteroatoms on the pore walls, as well as excellent photo redox properties in one structure, thereby greatly improving their adsorption performances for gold ion (Au 3+ ). Significantly, COF‐JLU63 shows an impressive uptake capacity of 7598 mg g −1 with high selectivity, rapid kinetics and excellent recyclability under visible light illumination, making it the new benchmark of adsorbents for Au recovery up to now. Multiple spectroscopy and theoretical simulation demonstrate that the triazocoronene‐based COF‐JLU63 not only exhibits rapid adsorption and large uptake capacity for Au 3+ , but also own effective photoreduction ability for Au 3+ into Au 0 . Such the well‐matched synergistic effects in adsorption and photoreduction is crucial in enhancing the Au recovery. This work contributes valuable insights for the synthesis of high‐performance precious metal adsorbents at molecular level.
A decision-making framework integrating energy efficiency and climate resilience: evidence from ASEAN economies
Accelerated Discovery‐to‐Unveiling of High‐Performance and Affordable Ammonia Electrode Process by Human–Machine Collaboration Framework
ABSTRACT The electrochemical nitrate reduction reaction (eNO 3 RR) to ammonia (NH 3 ) is a key for producing fuels during interstellar travel and an alternative to Haber−Bosch process. However, the complicated multi‐electron/proton transfer electrode process of eNO 3 RR makes affordable electrocatalyst discovery and its mechanistic understanding challenging. Herein, we established a human–machine collaboration framework by employing dimensionally reduced reaction descriptors which enables an accelerated data‐driven discovery‐to‐unveiling of unconventional and high‐performance eNO 3 RR electrocatalysts with desirable element choice. Using the current density difference between nitrite (NO 2 − ) reduction and hydrogen evolution as a descriptor, the optimal FeCoNiCuGa electrocatalyst was identified in a drastically short timeframe. Even compared with Pt or Rh, the FeCoNiCuGa exhibits a higher NH 3 production rate of 9.8 mmol mg cat −1 at −0.3 V versus a reversible hydrogen electrode. Furthermore, together with a mechanistic study using rotating ring‐disk electrode combined with a new kinetic model, in situ infrared spectroscopy unveiled that the adsorbed NO 2 − (*NO 2 − ) plays a crucial role in the efficient electrode process: a moderate *NO 2 − binding accelerates NH 3 formation whereas a weak binding leads to unfavorable reactions. Our work demonstrates that a comprehensive human–machine collaboration approach enables an accelerated discovery‐to‐unveiling of promising electrode processes, providing a feasible way to promote game‐changing electrochemical technologies.
Industrial green transformation efficiency and its driving factors in resource-based cities: the case of the Yellow River Basin
Abstract Enhancing industrial green transformation efficiency (IGTE) of resource-based cities in the Yellow River Basin is critical for upgrading industries, controlling carbon emission, and fostering sustainable high-quality development. This study evaluates the IGTE of 40 resource-based cities within the basin from 2010 to 2021 using the Super-SBM model, and analyzes its spatiotemporal evolution. Furthermore, the Tobit model is employed to identify the driving factors of IGTE. The results indicate that: (1) During the study period, the IGTE of resource-based cities shows a fluctuating upward trajectory. From a spatial perspective, cities located in the lower reaches perform better than those in the middle and upper reaches. Regarding development stages, growing cities achieve the highest level of IGTE, followed by regenerative ones, whereas mature and declining cities exhibit comparatively lower efficiency. (2) At the basin-wide level, both economic development and environmental regulations exert significant positive effects on IGTE. (3) For mature cities, industrial structure upgrading and industrial agglomeration contribute positively to IGTE improvement. In contrast, technological advancement and industrial structure show no significant promoting effect in declining and regenerative cities. Based on these results, this paper proposes targeted policy recommendations to facilitate a balance between economic growth and environmental government in ecologically vulnerable regions like the Yellow River Basin.
Spiro‑Linked Double Tetraphenylethenes: Solid‐State Emission and Circularly Polarized Luminescence Imaging
ABSTRACT Herein, we report the synthesis and structural characterization of two spiro‐linked tetraphenylethenes and investigate their optical properties in solution, as aggregates, and in the solid state. This family comprises two double spirobisanthracene‐tetraphenylethene hybrid systems. Approaching the synthesis and understanding the structure of these unexplored spiro‐systems opens the door to studying their properties both in solution and in the solid state. Besides the structural novelty of the prepared compounds, their solid‐state optical properties are remarkable. White and blue emissions are observed in the double spirobisanthracene‐tetraphenylethene hybrid derivatives. In addition, one of the synthesized compounds is chiral, and separation of its enantiomers enable the study of their chiroptical properties, revealing circularly polarized luminescence in films, aggregates and dispersions. Crystals were analyzed via circularly polarized luminescence microscopy, allowing the identification of racemic and enantiopure crystals via single‐particle analysis. This work paves the way for a further extension of the spirobisanthracene capabilities toward their implementation in emissive devices.
Fine grained reranking via caption bridging for knowledge augmented visual question answering
Multidentate Chelation Modulates PbI <sub>2</sub> Crystallization and Buried‐Interface Formation in Perovskite Solar Cells
ABSTRACT The buried interface in two‐step processed perovskite solar cells (PSCs) remains a major performance‐limiting factor, primarily due to incomplete PbI 2 conversion and defect‐induced nonradiative recombination. Here, we demonstrate a rational molecular engineering strategy by employing a multifunctional additive, pentaerythritol tetrakis(2‐mercaptoacetate) (PTAC‐SH), featuring synergistic thiol and carbonyl coordination sites. Multidentate chelation between PTAC‐SH and Pb 2+ directs the formation of porous PbI 2 scaffold, enabling efficient infiltration, and conversion of organic salts. Notably, PTAC‐SH spontaneously enriches at the buried interface during crystallization, enabling in situ and targeted passivation of interfacial defects. Consequently, PTAC‐SH simultaneously regulates crystallization to yield large‐grained, high‐quality perovskite films, effectively passivates interfacial defects, and optimizes energy‐level alignment. As a result, FA 0.84 MA 0.16 PbI 3 ‐based devices incorporating PTAC‐SH achieve a champion power conversion efficiency (PCE) of 25.33% with exceptional operational stability, retaining 95% of the initial PCE after 1700 h of maximum power point tracking. The generality of this approach is further corroborated in FA 0.98 Cs 0.02 PbI 3 ‐based devices, delivering a champion PCE of 26.07% with a high open‐circuit voltage of 1.199 V. This work highlights the pivotal role of structure‐guided molecular design for concurrently PbI 2 template engineering and buried‐interface optimization in high‐performance PSCs.
QS-MADS: quorum sensing perturbation-driven adaptive multi-agent scheduling for distributed power grids
Catalyst‐Controlled Chemodivergent Carbene Transfer Reactions With Bicyclo[1.1.0]butane‐Derived Acceptor Metallocarbenes
ABSTRACT Transition‐metal‐catalyzed carbene transfer reactions are powerful tools in organic synthesis, yet they traditionally rely on diazo compounds, which raise stability and safety concerns. While alternative precursors have emerged, a general, redox‐neutral, and atom‐economical platform for metallocarbenes generation remains a persistent challenge. Herein, we introduce carboxamide‐functionalized BCBs as versatile carbene precursors that undergo catalyst‐controlled chemodivergent reactions. Under nickel catalysis, cyclopropanation of multisubstituted alkenes proceeds via an acceptor‐type Ni‐carbene, affording azabicyclo[n.1.0] architectures bearing up to three contiguous stereocenters with excellent diastereocontrol. In contrast, copper catalysis promotes efficient and chemoselective formal C(sp 2 )─H insertion to access allyl oxindoles. Both protocols exhibit broad substrate scope, high functional group tolerance, and exceptional atom economy, and their synthetic utility is highlighted through the preparation of core structures of bioactive compounds. Computational and experimental studies reveal that Ni‐carbene generation proceeds via a stepwise dual C─C cleavage, contrasting with the concerted dual cleavage and subsequent electrophilic aromatic substitution manifold established for the copper system.