Browse Articles

Correction: Potential airborne transmission of SARS-COV-2 through bathroom ventilation ducts associated with an outbreak in a residential building in Santander, Spain, 2020

Reprogramming NAD(P) ⁺ ‐Binding Proteins for Iminium Biocatalysis via a Synthetic NAD ⁺ ‐Type Cofactor

ABSTRACT Efficient integration of non‐natural catalytic motifs into protein scaffolds remains a central challenge in artificial enzyme design. Here we report aniline adenine dinucleotide (AnAD), a NAD + ‐type synthetic cofactor in which the native nicotinamide is replaced by a catalytically active aniline unit. When incorporated into diverse NAD(P) + ‐binding proteins, AnAD introduces an iminium catalysis mechanism that enables tandem Friedel‐Crafts alkylation‐enantioselective protonation reactions. Screening a panel of natural protein scaffolds revealed broad intrinsic compatibility, while protein engineering further enhanced activity and stereoselectivity, affording artificial enzymes with good substrate generality and tunable enantioselectivity. Mechanistic studies showed that cooperation between AnAD and protein microenvironments, particularly dynamic active‐site loop motions, governs both reactivity and enantioselectivity. These results demonstrate the generality and robustness of reprogramming ubiquitous NAD(P) + ‐binding proteins for new‐to‐nature biotransformations using NAD + ‐type synthetic cofactors.

Dual roles of oxygen vacancy in hafnium oxide for passivating silicon surface defects

Oxygen vacancy (VO) defects serve as the primary electron traps, addressing the limited out-of-plane carrier transport in HfO2-passivated Si-based heterojunction devices, while their roles in passivating Si surface defects have seldom been studied before. In this work, HfO2 thin films with various VO defect densities were grown via the atomic layer deposition method by simply varying the H2O dosage during the growth procedure. The results suggest that introducing VO defects into HfO2 thin films degrades the overall surface passivation efficiency on N-type Si. Further studies suggest that VO defects are the primary source of fixed positive charges in HfO2 thin films, which induce remarkable field-effect passivation. In contrast, introducing VO defects into HfO2 degrades the chemical passivation by suppressing the interfacial layer formation. This work demonstrates dual roles of VO defects in HfO2 thin films in passivating Si surface defects, offering clues to optimize the HfO2 passivation layer by carefully modulating and positioning VO defects to achieve both efficient interfacial passivation and effective interfacial transport in HfO2-passivated Si-based devices in the future.

Multi-characterization-assisted construction of the molecular structure of high-volatile bituminous coal

Elucidating coal molecular structures is critical for studying its structure–property relationships and advancing efficient coal resource utilization. In this study, a bituminous coal (JSM_C) was selected from the coal-rich Inner Mongolia region of China as the research object. Multi-characterization technologies, including elemental analysis, 13 C solid-state nuclear magnetic resonance spectroscopy ( 13 C NMR), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), were integrated to characterize the elemental composition, carbon skeleton, functional groups, and nitrogen species in JSM_C. The results showed that the molecular formula of JSM_C is C 176 H 128 O 19 N 2 . The carbon skeleton is centered on mono-/bi-/tricyclic aromatics connected by aliphatic or oxygen-linked chains. The oxygen-containing functional groups are mainly phenols and ethers, while nitrogen species exist in the form of pyridine and pyrrole heterocycles. The simulated spectra of NMR and FTIR are consistent with the experimental data, confirming the reliability of the constructed structure. This study achieved the construction of complex coal macromolecules from the specific mine through “characterization analysis-model construction-simulation verification,” providing a feasible paradigm for coal molecular structure research. It also lays a molecular foundation for investigating structure-performance relationships and introducing related algorithmic models in coal research.

Direct Photocatalytic Conversion of Methane to Acetone Through a Synergistic Ta Single‐Atom/Ga Lewis Acid Catalyst

ABSTRACT Direct photocatalytic conversion of methane to ≥ C3 oxygenates under ambient conditions remains highly challenging and largely unexplored due to the current carbon‐terminated adsorption configurations and insufficient concentration of intermediates. Herein, we demonstrated efficient γ‐Ga 2 O 3 quantum dot catalysts with high‐density Ta single atoms anchored at Ga IV vacancies (Ta 1 ‐Ga 2 O 3 QDs), featuring a synergistic Ta single‐atom/Ga Lewis acid architecture. The unsaturated d 0 ‐TaO 4 site stabilizes key acetyl intermediates in a distinctive oxygen‐terminated η 1 (O)‐CH 3 CO configuration, minimizing steric hindrance while enhancing carbonyl carbon electrophilicity, greatly facilitating the second C–C coupling step. Concurrently, Ga sites enrich –CH 3 intermediates for sequential C–C coupling conversion. The synergistic architecture achieved single‐step photocatalytic conversion of CH 4 and H 2 O to acetone with a yield of 86.7 µmol g −1 h −1 , with the carbon‐based selectivity of 56.2% or the liquid phase selectivity of 81.2%, and a 20.7% apparent quantum yield (AQY) at 254 nm, which has not been achieved by the current noble metal‐based photocatalysts. This work demonstrates the unique capability of unsaturated d 0 single‐atom sites for modulation of intermediate configurations, unlocking a pathway for ≥ C3 oxygenate synthesis from methane.

Polarization-dependent, morphology-driven alignment and stability of microparticles via optical tweezers

In this Letter, we observed the polarization-dependent axial alignment effect of microparticles induced by a highly focused laser beam. We theoretically and experimentally verified that the microparticles align due to morphology-dependent optical torque generated by the interaction between shape-dependent polarizability and the longitudinal field component near the focal region. We found that a linearly polarized beam plays a significant role in stabilizing the post-alignment microparticles, whereas circular and elliptical polarization beams cause the microparticles to rotate rather than remain stable. We further show that particle size and moment of inertia significantly influence the alignment behavior, where larger particles exhibit a slower response and enhanced stability due to inertia. The proposed mechanism enhances the understanding of polarization-dependent alignment and particle-size effects, enabling precise control of the orientation dynamics of shape-dependent microparticles in microfluidic and micromechanical applications.

An optimized three-laser 27-color spectral flow cytometry panel for multi-organ profiling in mice

While high-dimensional flow cytometry plays critical roles in resolving complex cellular networks, there remains a scarcity of comprehensive panels for the simultaneous profiling of diverse mouse cell types, primarily due to the technical challenges of spectral overlap and the limited availability of mouse-validated reagents. To address this technical gap and resolve diverse cell populations in murine models, we designed a 27-color flow cytometry panel optimized for 3-laser spectral flow cytometers. This optimized panel enables broad and simultaneous detection of 16 distinct cell subsets from both lymphoid and myeloid lineages—including T cells, B cells, plasma cells, NK cells, innate lymphoid cells, dendritic cells, monocytes, macrophages, neutrophils, eosinophils, basophils, mast cells—along with non-immune cells, such as epithelial, endothelial, fibroblast, and neuronal-associated cells. The panel has been successfully applied to various tissues, including spleen, thymus, bone marrow, peripheral blood, mesenteric lymph nodes, peritoneal lavage fluid, gut epithelium, and lamina propria. Applying this panel to a poly(I:C) model, we successfully tracked systemic shifts in monocyte and neutrophil populations and identified a previously unrecognized, Cyp11b1 -expressing immune cell subset via reporter expression. This panel will facilitate high-dimensional immune profiling on standard 3-laser cytometers, providing a robust tool for dissecting cellular landscapes across diverse contexts.

A Multifunctional Sulfur(VI) Fluoride for SuFEx Reactions: <i>N</i> ‐CF ₂ H Sulfamoyl Fluorides

ABSTRACT Sulfur(VI) fluorides based on sulfur(VI) fluoride exchange (SuFEx) chemistry have demonstrated their unique versatility and high efficiency in the field of medicinal chemistry. Acting as both covalent and hydrogen bond donors, the novel N ‐CF 2 H sulfamoyl fluoride will enhance the binding strength between drugs and receptors in organism, thereby injecting new vitality into the research of targeted drugs. Herein, we report the two‐step synthesis of N ‐CF 2 H sulfamoyl fluorides from primary amines via successive fluorosulfonylation and insertion of difluorocarbene. This method shows broad scope, provides a platform for rapidly generating N ‐CF 2 H sulfamoyl fluorides by virtue of the diversity and availability of amines. The stability of N ‐CF 2 H sulfamoyl fluorides was tested in aqueous environment at different pH, showing that most compounds remained &gt;95% intact for 72 h. As a novel SuFEx building block, N ‐CF 2 H sulfamoyl fluoride shows chemoselectivity toward phenol and does not react with amines and alcohols. Besides, N ‐CF 2 H sulfamoyl fluorides were subjected to debenzylation and amide‐bond‐formation reactions to generate peptides, Sitagliptin derivative and bioactive alkylamine. Finally, N ‐CF 2 H sulfamoyl fluoride underwent successful F‐18 labeling. With the reported syntheses, we believe that N ‐CF 2 H sulfamoyl fluoride will soon be practically applied in drugs, covalent targeted radioligand, F‐18 PET tracers, electrolyte in general.

Photodarkening in crystalline BaGa4Se7

Nonlinear chalcogenide single crystals play a key role in mid-infrared photonics, enabling efficient frequency conversion and high-power laser operation. In this work, we report room-temperature photodarkening (photochromism) in the chalcogenide crystal BaGa4Se7. Optical transmission measurements with polarized light indicate that the band edge varies by 55–75 meV as the sample is rotated by 90°, due to the anisotropy of the monoclinic structure. When illuminated with a 475 nm LED, near the direct bandgap of ∼2.62 eV, the transmission drops by 5%–8%, depending on the crystallographic orientation. The crystals recover their transmission at room temperature with stretched-exponential kinetics and a time constant of 10–20 h, consistent with carriers escaping from traps with a range of activation energies rather than from a single well-defined barrier.

Herpes simplex virus type-1 ocular infection in thrombospondin-1 deficient C57BL/6J mice

Herpes simplex virus type 1 (HSV-1) corneal infection triggers an immunopathological response and corneal neovascularization leading to vision impairment. Thrombospondin-1 (TSP-1) is a matricellular protein shown to regulate inflammatory processes and vascularization in the cornea. The purpose of this study was to determine if loss of TSP-1 alters the pathology of HSV-1 keratitis. The recombinant virus INV-2C or the low passage orolabial HSV-1 isolate, Ikey, were administered to scarified corneas of 8-week-old Thbs1 -/- and control C57BL/6J mice. Blepharitis, corneal neovascularization, corneal clouding, weight loss, viral titers, and mortality were determined on multiple days post infection. Corneal nerve loss was evaluated on day 2 and day 7. Neutralizing antibody, T-cell responses, and infiltrating cells in the aqueous and vitreous humors were quantified. There was no significant difference between Thbs1 -/- and C57BL/6J control mice when comparing any corneal disease outcome with either virus. Severe pan-uveitis developed in both C57BL/6J and Thbs1 -/- mice infected with the Ikey strain of virus. There were no significant differences in antibodies to HSV or in the number of HSV-1 specific IFN-g secreting T-cells in the spleen between C57BL/6 or TSP-1 -/- mice. The lack of TSP-1 did not affect the severity of corneal disease, immune responses to HSV-1, or sensory nerve loss suggesting either TSP-1 functions are not involved in HSV-1 pathogenesis or that other members of the TSP family can substitute for the loss of TSP-1.

Photocracking of Polystyrene into Aromatic Products in CH ₂ Cl ₂

ABSTRACT Photocatalytic cracking of polystyrene (PS) into valuable aromatic chemicals presents a key route to plastic waste upcycling under mild conditions, in which CH 2 Cl 2 is often used as an inert solvent. Represented herein is to report an unexpected cracking of PS to C6‐C8 aromatic products in CH 2 Cl 2 without any additional photocatalysts under an O 2 atmosphere and 365‐415 nm irradiation. Remarkably, this photocatalyst‐free system achieves a maximum generation rate of 15.9 µmol/h for C6‐C8 aromatic products, competitive with state‐of‐the‐art systems that rely on external photocatalysts. Radical scavenging experiments and EPR spectra reveal that chlorine (Cl•) radicals generated from CH 2 Cl 2 under irradiation contribute to the cleavage of C─H/C─C bonds in PS, leading to the formation of C6‐C8 aromatic products. Under aerobic conditions, these Cl• radicals also promote the transformation of PS into carbonylated intermediates as the light‐absorbing species with an absorption range of 300‐500 nm, thereby accelerating the activation of PS and derivatives. Importantly, this work identifies, for the first time, CH 2 Cl 2 as a vital photochemical reagent in PS conversion to value‐added aromatics even under visible light irradiation.

W ₁ /TiO ₂₋ <i> _x </i> Enabled Photoelectrochemical Tandem Upgrading of Glycerol to Nucleoside Precursors

ABSTRACT Pentose aminooxazoline (PAO) is a key precursor in the synthesis of nucleoside and carbohydrate drugs. However, conventional PAO synthesis methods are hindered by slow reaction rates, low yield, and instability of raw material glyceraldehyde (GLD). Herein, we report a highly efficient photoelectrochemical tandem synthetic pathway that overcomes the fundamental limitations. Using biomass‐derived glycerol as the feedstock, we achieve highly selective in situ photoelectrosynthesis of GLD on a defective TiO 2 photoanode decorated with W single‐atom (W 1 /TiO 2−x ). Importantly, this photoanode enhances the stability of in situ generated GLD, beneficial to its tandem addition reaction with 2‐aminooxazole (2‐AO) for PAO synthesis. Under optimized conditions, the system delivers a PAO yield of 3.72 µmol h −1 cm −2 , 54‐fold enhancement over the conventional method. We demonstrate the synergistic interaction between oxygen vacancies and W single‐atom not only preserves the C‐C bond to ensure the high selectivity of GLD but also significantly enhances the electrophilicity of carbonyl carbon in GLD. This greatly improves the addition reaction between 2‐AO and in situ generated GLD toward PAO yield. This work provides a green, efficient, and scalable strategy for PAO synthesis, fundamentally addressing the long‐standing challenges of feedstock instability and low yield associated with traditional methods.

Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices

Planar germanium is currently the only semiconducting platform where high-coherence spin qubits and proximity-induced superconductivity have each been demonstrated. Recent research into spin qubits in Ge/SiGe heterostructures has focused on increasing the thickness of the SiGe capping layer, reporting improvements in the electrostatic noise levels. Meanwhile, heterostructures with thinner capping layers remain rather unexplored, despite the potential advantages for proximity-induced superconductivity. Here, we study a Ge/SiGe heterostructure with a thin SiGe cap d≈4 nm and investigate its viability to host low-noise quantum dots. To keep the thermal budget compatible with superconducting layers, low-temperature oxide deposition processes were developed and implemented for the gate dielectrics. The charge noise level of the fabricated devices is estimated to be 1.8 ± 1.0 μeV/Hz, comparable to devices fabricated on shallow heterostructures (d∼20 nm) with high-temperature deposited oxides. Low charge noise levels, together with the straightforward integration of superconductors, make this heterostructure an attractive platform for prototyping hybrid semiconducting–superconducting devices.

Perinatal mental health among South Asian immigrant women in Canada: A scoping review protocol

Perinatal mental health concerns are common and may be heightened among immigrant populations because of migration-related stressors, social isolation, stigma, language barriers, and limited access to culturally safe care. Although previous reviews have examined perinatal mental health among immigrants broadly, evidence focused specifically on South Asian immigrant women in Canada across pregnancy and the postpartum period has not been comprehensively mapped. South Asian women represent one of the largest and fastest-growing immigrant populations in Canada and may experience unique cultural, familial, linguistic, and migration-related factors that shape perinatal mental health experiences and access to care. This scoping review will map the extent, range, and nature of evidence on perinatal mental health among South Asian immigrant women in Canada by examining reported mental health outcomes, associated risk and protective factors, help-seeking experiences, and barriers and facilitators to accessing support services, and identify gaps to inform future research, practice, and policy. This protocol was developed in accordance with Joanna Briggs Institute guidance for scoping review protocols and reported using the PRISMA-P checklist, where applicable (see S2 Checklist). The completed scoping review will be reported according to the PRISMA-ScR checklist. MEDLINE, Embase, PsycINFO, CINAHL, and Scopus will be searched for literature published from January 2000 to the date of the final search. Grey literature will be identified through targeted searches of government, public health, professional, and community organization websites. Eligible sources will include qualitative, quantitative, mixed-methods, and relevant grey literature addressing perinatal mental health during pregnancy and up to 12 months postpartum among South Asian immigrant women residing in Canada. Inclusion criteria are immigrant women of South Asian origin from counties such as India, Pakistan, Bangladesh, Sri Lanka, Afghanistan, Nepal, Bhutan, and Maldives residing in Canada during the perinatal period. Two reviewers will independently screen titles, abstracts with disagreements resolved through discussion or third-reviewer adjudication. Data will be extracted using a standardized charting form and summarized using descriptive mapping and narrative synthesis. Protocols and planned studies will be charted separately from completed studies. Consistent with scoping review methodology, formal exclusion of studies based on methodological quality will not be undertaken; however, study characteristics and reported methodological limitations will be charted to support interpretation of the evidence base. Ethics approval is not required because the review will use publicly available sources only. Findings will be disseminated through a dissertation, peer-reviewed publication, and conference presentations. The review will provide a comprehensive overview of existing evidence and knowledge gaps to support culturally responsive perinatal mental health research, policy development, and healthcare practice for South Asian immigrant women in Canada. This protocol has been preregistered on the Open Science Framework:10.17605/OSF.IO/FZN4S.

Self‐Optimization With Oriented Facet Reconstruction for Universal Electrocatalytic C–N Coupling

ABSTRACT Electrocatalytic C–N coupling represents a green synthesis platform, yet the dynamic evolution of catalyst surfaces during the reaction remains poorly understood. Here, we report a nitrate‐dominated, preferential facet evolution on Cu single crystals that directs less active (110) and (100) facets toward the highly active (111) configuration. The Cu(111) surface delivers a urea yield of 5.2 mg h −1  cm −2 from CO 2 and NO 3 − , outperforming (110) and (100) by about 4‐ and 26‐fold, respectively, while maintaining excellent stability. Experimental and theoretical analyses reveal that this facet reconstruction is associated with spontaneous chemical interaction between nitrate and metallic copper, alongside the thermodynamic stability of the Cu(111) facet. Significantly, the pristine Cu(111) surface consistently outperforms Cu(110) and Cu(100), highlighting its intrinsic catalytic superiority. This work provides insights into nitrate‐dominated C–N coupling, advancing the design of dynamically active electrocatalysts.

Hydrogenation of CO ₂ to Methanol Catalyzed by In ₂ O ₃ : Oxygen Vacancies, Surface Hydroxyl Groups, and Temperature Dependence for Reactivity Revealed by ¹⁷ O NMR

ABSTRACT Catalytic hydrogenation of CO 2 over In 2 O 3 has attracted intense interest due to its exceptionally high methanol selectivity and broad tunability through structural modification. However, the precise formation mechanism of oxygen vacancies (OVs) and exact roles of hydroxyl groups (InOHs), the two most important surface structures, remain poorly understood due to the limited resolution of currently available characterization methods. Here, by employing an advanced 17 O labeling strategy combined with high‐field solid‐state NMR (ssNMR) up to 18.8 T, we achieve exceptionally high spectral resolution of 17 O NMR, enabling explicit separation of distinct surface oxygen species. This approach allows tracing the thermal evolution of these species and probing their reactivities toward CO 2 activation and hydrogenation. Notably, surface OIn 3 sites are identified as the OV precursors, with a formation barrier of approximately 200°C. Unexpectedly, room‐temperature oxygen exchange between In 2 O 3 and CO 2 is observed, enabled by the high sensitivity of the new 17 O NMR method. Further probing with 13 CO 2 and/or H 2 , at variable temperatures, we are capable of unraveling the roles between OVs, InOHs and surface lattice oxygen species in CO 2 /H 2 activation and their stepwise conversion into formate intermediates and ultimately methanol, which may prompt rational designs to lower the reaction temperature for In 2 O 3 .

Nonvolatile phase-state-gated OAM metasurface holography for dual-key access

Orbital-angular-momentum (OAM)-selective metasurface holography offers a promising route for spatial-mode encryption, but purely modal multiplexing is often limited by intermodal leakage, increased sampling demands, and static channel access. Here, we demonstrate a nonvolatile phase-state-gated OAM meta-hologram based on Sb2S3, where the amorphous/crystalline end point state serves as a persistent material-state key and the incident (ℓ, M) structured beam serves as an optical key. A holographic channel is reconstructed only when both keys are simultaneously matched. To overcome the state-dependent phase-efficiency mismatch of Sb2S3, end point-specific meta-atom libraries and pixel-wise joint layout optimization are used to encode two state-dependent holographic responses into one static metasurface. At 680 nm, the device realizes four selectively addressable channels from two mode keys and two nonvolatile end point states, with end point reconstructed-image normalized cross correlation values ranging from 0.84 to 0.89. Channel selectivity is quantified using a fixed-window normalized cross correlation matrix, where each experimental reconstruction is compared with all four target patterns within the same evaluation window. Intermediate crystallization levels produce hybrid reconstructions due to end point-library mismatch, indicating that reliable multilevel expansion requires dedicated state-specific libraries and encodings. This work extends OAM meta-holography from purely optical modal multiplexing toward nonvolatile material-state-gated access, offering a compact platform for dual-key optical encryption and reconfigurable holographic displays.

Partisan differences in healthcare decision-making: Evidence from a vaccine experiment

Policymakers use information campaigns to alter health behaviors, but their effectiveness depends on how the information compares to viewers’ initial beliefs and their perceptions of its value. In August 2024, we experimentally tested whether political identity influenced how individuals responded to information about the COVID-19 vaccine. Our sample included 288 self-identified Democrats and 291 self-identified Republicans. We found that Democrats and Republicans similarly overestimated the frequency and severity of COVID-19 infections, as well as the vaccination rate. Participants were not better at predicting the COVID-19 experiences of their concordant party. However, participants who learned they underestimated the discordant party vaccination rate were more likely to report an intent to receive a COVID-19 vaccine.

DNA‐mimic for Specific Surface Functionalization of Zr‐MOFs for Bacterial Targeting

ABSTRACT Nanosized metal–organic frameworks (MOFs) are versatile platforms used in biomedical applications due to their high loading capacity, large surface area, and tunable functionality. Without surface modifications, these nanoparticles lack cell specificity and are prone to aggregation and degradation in biological environments, reducing their effectiveness. Surface attachment of DNA via phosphate group coordination to zirconium‐based MOFs improves stability, but DNA binding remains non‐site‐specific due to the abundance of phosphate groups in its backbone, limiting DNA's addressability for further functionalization. To address this issue, we present a novel, significantly faster single‐step approach for the post‐synthesis modification of the external surface of PCN‐222 nanoparticles using an uncharged synthetic mimic of DNA, peptide nucleic acids (PNA). By using phosphate‐modified PNA, we achieve surface functionalization through coordination with the Zr 6 clusters on the MOF surface. The modification produced monodispersed nanoparticles and resulted in slowed drug‐release kinetics compared to unmodified nanoparticles. PNAs enhanced attachment efficiency and hybridization specificity compared to DNA coatings, allowing subsequent conjugation of protein targeting moieties and enabling bacterial targeting of drug‐loaded MOFs. This work introduces phosphotyrosine‐modified PNA as a superior, single‐step surface coating for PCN‐222, allowing controlled post‐functionalization with single‐stranded DNA (ssDNA) and expanding applications in biomedical and materials science.

Giant modulation of the photogalvanic effect in two-dimensional SnP2S6/CuInP2S6 ferroelectric heterojunctions

The photogalvanic effect (PGE) enables the direct conversion of light into current in non-centrosymmetric materials, providing a promising route toward self-powered optoelectronics devices. However, achieving large and tunable photocurrents in two-dimensional system remains a significant challenge. Here, we demonstrate a giant and hierarchically tunable PGE in a SnP2S6/CuInP2S6 ferroelectric heterojunction through the combined control of device contact symmetry, ferroelectric polarization, and optical polarization. Asymmetric contacts break the spatial inversion symmetry and enhance the photocurrent ∼50× compared with symmetric contacts at 0.8 eV. In addition, switching the ferroelectric polarization of CuInP2S6 leads to an eightfold increase in photocurrent at 2.4 eV. Moreover, circularly polarized light generates a photocurrent that is 13 times larger than that induced by linearly polarized light at the same photon energy. These results demonstrate an effective strategy for achieving giant photocurrent modulation in two-dimensional ferroelectric heterojunctions and provide foundations for high-performance and reconfigurable optoelectronic devices.