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ZnO nanorods arrays are respectively prepared under different vapor pressures with opening (OZN) or sealing (SZN) of the beaker. The results from time-resolved photoluminescence measurements indicate that sealing the beaker during the growth process can effectively suppress the surface recombination of ZnO nanorods, and the suppression effect is even better than a 500 °C post-thermal treatment of OZN samples. The results from X-ray photoelectron spectroscopy measurements reveal that the main reason for this phenomenon is that the surfaces of the SZN samples are attached by groups related to NH3 instead of the main surface recombination centers such as OH and H groups in the OZN samples. The ammonia surface treatment on both OZN and SZN samples further testifies that the absorption of the groups related to NH3 does not contribute to the surface recombination on the ZnO nanorods. Low temperature (1.8 K) decay curves for samples grown in an open beaker (OZN), an open beaker with post-growth annealing at 500 °C in air (OZN-A), and a sealed beaker (SZN) are fitted by two exponential decays according to the equation I(t) = ASe−t/τS + ABe−t/τB. The inset indicates that sealing the beaker during the growth process can effectively suppress the surface recombination of ZnO nanorods, and the suppression effect is even better than a 500 °C post-thermal treatment of OZN samples. [ABSTRACT FROM AUTHOR]

Pathological aggregation of essentially dissociated Transthyretin (TTR) monomer proteins, driven by misfolding and self-interaction, is associated with Transthyretin amyloidosis (ATTR) disease. The TTR monomer proteins consist of several fragments that tend to self-aggregate. Recent experimental studies showed that the sequence of residues TTR 91-96 plays an important role in self-aggregation. However, the mechanisms underlying the misfolding and aggregation of the TTR 91-96 monomers are still unknown. In this study, we used microsecond molecular dynamics simulations to investigate the misfolding and self-assembly of TTR 91-96 Octamers. We also investigated E92P and V94P mutants for comparative analysis. The analysis indicates that hydrophobic interactions and π-π stacking patterns play important roles in reducing the β-sheet content in the V94P and E92P mutants. Additionally, our findings reveal the conformational transition of TTR 91-96 octamer from closed β-barrel, open β-barrel to the β-bilayer aggregation. We further elucidate the dynamic mechanism of the transition from intermediate states to stable states. Overall, our research may contribute to the development of drug design to combat fibrous amyloid fibrous diseases.

Bacterial infections pose significant challenges in wound healing and are a serious threat to human health. Hydrogels have emerged as an ideal wound dressing due to their three-dimensional network, which facilitates exudate absorption and maintains a moist environment conducive to healing. Herein, we developed integrated hydrogels composed of poly(thioctic acid) (PTA), polydopamine (PDA), and curcumin (Cur). The formation of covalent and hydrogen bonds among PTA, PDA, and Cur endowed the hydrogels with excellent self-healing and bioadhesion properties. These hydrogels were utilized as dressings for healing Staphylococcus aureus -infected wounds. The PDA-PTA-Cur 16 hydrogel showed the best overall performance in stability, bioadhesion, antioxidant activity, and antibacterial effectiveness. The in vivo results revealed that the PDA-PTA-Cur 16 hydrogel accelerated infected wound healing by inhibiting bacterial growth, alleviating inflammation, promoting collagen deposition, and inducing angiogenesis. This multifunctional hydrogel not only enhances wound healing but also presents a promising strategy for combating bacterial infections in clinical settings.

Nitrite (NO 2 - ) is attracting increasing attention due to its harmful effect on human health. Thus, it is highly desirable to construct effective electrochemical sensors to detect the presence of NO 2 - . The majority of electrochemical NO 2 - detection is focused on alkaline or neutral electrolyte solutions and is rarely reported under acidic conditions. In this work, a tetraphenylethylene (TPE)-based 2D lanthanide metal-organic framework (Ln-MOF), (Me 2 NH 2 )[Ho III (tcbpe-F)DMF]•DMF•H 2 O ( 1 ) (tcbpe-F = 4',4‴,4″‴,4″″‴-(ethene-1,1,2,2-tetrayl)tetrakis(3-fluoro-[1,1'-biphenyl]-4-carboxylic acid, DMF = N,N -dimethylformamide)), has been successfully fabricated on carbon paper ( CP ) by an in situ hydrothermal method. As a NO 2 - sensor, the fabricated 1 electrode exhibited excellent electrochemical performance in the H 2 SO 4 electrolyte (pH = 1) and offers high sensitivities of 1453.2 and 591.5 μA mM -1 cm -2 , with a wide linear detection range of 0.1 μM to 9 M, a low detection limit of 60 nM, excellent specificity even in the presence of various analytes (metal ions, anions, and organic molecules) and real water samples, satisfactory stability, and reproducibility. This is the first report of TPE-based Ln-MOF as a NO 2 - sensor, and furthermore, a plausible sensing mechanism is confirmed by experiments and theoretical computations.

The efficient conversion of carbon dioxide (CO 2 ) requires the development of stable catalysts with high selectivity and reactivity within a wide potential range. Here, the high-entropy metal sulfide CuAgZnSnS 4 is designed for CO 2 reduction with excellent performance (FE carbon products ≥ 90%) in whole test potential windows (600 mV) based on the synergistic effect of the high-entropy metal sulfide. In particular, CuAgZnSnS 4 exhibits better single-product selectivity with the highest FE HCOOH /FE CO value (29.03) at -1.28 versus reversible hydrogen electrode (RHE). In combination with in situ measurements and theoretical calculations, it is further revealed that the synergistic effect of CuAgZnSnS 4 realizes the controllable regulation of the surface electronic structure at Sn active sites, strengthening orbital interactions between *OCHO and Sn active sites. As a result, the effective adsorption and activation of *OCHO instead of *H are obtained, improving the single-product selectivity of electrocatalytic CO 2 reduction and inhibiting the competitive hydrogen evolution reaction significantly. Our findings may complete the understanding of the synergistic effect for high-entropy materials in catalysis and offer new insight into the design of efficient electrocatalysts with high catalytic activity.

High-altitude exposure can adversely affect neurocognitive functions; however, the underlying mechanisms remain elusive. Why and how does high-altitude exposure impair neurocognitive functions, particularly sleep? This study seeks to identify the molecular markers and mechanisms involved, with the goal of forming prevention and mitigation strategies for altitude sickness. Using serum proteomics and metabolomics, we analyzed blood samples from 23 Han Chinese plain dwellers before and after six months of high-altitude work in Tibet. The correlation analysis revealed biomarkers associated with cognitive alterations. Six months of high-altitude exposure significantly compromised cognitive function, notably, sleep quality. The key biomarkers implicated include SEPTIN5, PCBP1, STIM1, UBE2L3/I/N, amino acids (l/d-aspartic acid and l-glutamic acid), arachidonic acid, and S1P. Immune and neural signaling were suppressed, with sex-specific differences observed. This study innovatively identified GABA, arachidonic acid, l-glutamic acid, 2-arachidonoyl glycerol, and d-aspartic acid as biomarkers and elucidated the underlying mechanisms contributing to high-altitude-induced neurocognitive decline with a particular focus on sleep disruption. These findings pave the way for developing preventive measures and enhancing adaptation strategies. This study underscores the physiological significance of high-altitude adaptation, raising new questions about sex-specific responses and long-term consequences. It sets the stage for future research exploring individual variability and intervention efficacy.

Rechargeable neutral zinc-air batteries are attracting enormous research interest due to their long lifetime and low cost. However, the sluggish kinetics of the air cathode in the neutral electrolyte reduces the catalytic performance and impedes the power density and energy efficiency of zinc-air batteries. In this work, we propose a universal, sustainable, and effective approach to improve the kinetics of the air cathode through a solar-energy-induced photothermal effect. By illumination of the cost-effective carbon-black-based cathode, the temperature of the air cathode increases from room temperature to 40.5 °C, thereby accelerating the kinetics for the electrocatalytic reaction and reducing the interfacial resistance of the zinc-air battery. Attributed to the sunlight-promoted reaction kinetics, the neutral zinc-air battery exhibits a higher power density of 2.89 mW cm -2 and longer cycling durability over 250 h, 116 and 156% times the one without light illumination, significantly improved in contrast to the one without light illumination. Furthermore, we demonstrated solar energy-driven and solar-enhanced charging in the daytime and discharging at night, potentially applying in distributed energy storage applications. The proposed sustainable solar-energy-promoted reaction kinetics of air cathodes will drive the development of efficient zinc-air batteries and also inspire the rational design of electrocatalytic electrodes in other electrochemical devices.

Azetidine units are commonly found in natural products and biologically active drugs. The [2 + 2] cycloaddition of imines and alkenes has been extensively used in the synthesis of such structures, while enantioselective approaches remain elusive. Herein, an efficient B(C 6 F 5 ) 3 /chiral phosphoric acid-catalyzed asymmetric [2 + 2] cycloaddition of ketimines and aryl vinyl selenides was presented, delivering valuable chiral azetidines with excellent stereoselectivities (>20:1 dr and up to 96:4 er). What's even more interesting was that when a "Se" atom was switched to an "S" atom, the reaction proceeded through a [2 + 2] cycloaddition/ring-opening cascade process, affording a range of chiral thioacetals with high enantioselectivities (up to 98:2 er), which were also important organic sulfur compounds. Mechanistic experiments, coupled with density functional theory (DFT) calculations, shed light on a mechanism involving stepwise [2 + 2] cycloaddition and ring-opening processes, with the initial alkenylation step identified as crucial for achieving stereoselective control.

High-fat diet (HFD) induced obesity is associated with depression-related behavioral and neurogenic changes and may lead to cognitive impairment. Fluoxetine (FXT), the most commonly used antidepressant, may alleviate depressive symptoms by increasing neurogenesis, but the potential efficacy of FXT for HFD-induced cognitive deficits is unclear. In this study, we established an obese HFD mouse model by feeding three-week-old male C57BL/6N mice with a chronic HFD for 18 weeks, then assessed adipose tissue morphology by magnetic resonance imaging and histopathology, assessed cognitive function by Morris water maze and novel object recognition tests, and detected DCX + and BrdU + expression in the hippocampal dentate gyrus (DG) region by immunofluorescence bioassay. Western blot detected brain-derived neurotrophic factor (BDNF) levels and CREB-BDNF pathway-related genes were assayed by Quantitative RT-PCR. The results of the study showed that HFD contributes to obesity and cognitive deficits, and more importantly, it also reduces BDNF expression and neurogenesis levels in the hippocampus. Subsequently, we found that treatment with FXT (10 mg/kg/day) ameliorated chronic HFD-induced cognitive deficits and increased the expression of Nestin, BrdU + , and DCX + in the DG, restored BDNF expression in the hippocampus and increased the expression of genes related to CREB , BDNF , NGF , and MAPK1 . In conclusion, our data elucidated that FXT ameliorates cognitive deficits and reduces chronic HFD-induced neurogenesis by restoring BDNF expression and CREB-BDNF signaling, this provides a good basis and scientific significance for future research on the clinical treatment of obesity.

A chemoenzymatic synthesis access to resibufogenin and bufalin was developed in seven steps without protecting groups. Starting with androstenedione (AD), an α-OH was introduced directly at C14 by hydroxylase P-450 lun , which was further used as the directing group for hydrogenation to fully control the C17 configuration in the β-orientation after Suzuki cross-coupling. Dehydration of 14α-OH followed by an epoxidation delivered resibufogenin. Simultaneously, bufalin was also obtained via a challenging anaerobic Mukaiyama hydration.

Efficiently capturing fluorocarbons, potent greenhouse gases with high global warming potentials (GWP), remains a daunting challenge due to limited effective approaches for constructing high-performance adsorbents. To tackle this issue, we have pioneered a novel strategy of developing radical porous materials as effective adsorbents for fluorocarbon capture. The resulting radical covalent triazine framework (CTF), CTF-azo-R, shows exceptional fluorocarbon (perfluorohexane, a representative model pollutant among fluorocarbons) uptake capacity of 270 wt %, a record-high value among all porous materials reported to date. Spectral characteristics, experimental studies, and theoretical calculations indicate that the presence of stable radicals in CTF-azo-R contributes to its superior fluorocarbon capture performance. Furthermore, CTF-azo-R demonstrates exceptionally high chemical and thermal stabilities that fully meet the requirements for practical applications in diverse environments. Our work not only establishes radical CTF-azo-R as a promising candidate for fluorocarbon capture but also introduces a novel approach for constructing advanced fluorocarbon adsorbents by incorporating radical sites into porous materials. This strategy paves the way for the development of radical adsorbents, fostering advancements in both fluorocarbon capture and the broader field of adsorption and separation.

Bacterial pneumonia has garnered significant attention in the realm of infectious diseases owing to a surge in the incidence of severe infections coupled with the growing scarcity of efficacious therapeutic modalities. Antibiotic treatment is still an irreplaceable method for bacterial pneumonia because of its strong bactericidal activity and good clinical efficacy. However, the mucus layer forming after a bacterial infection in the lungs has been considered as the "Achilles' heels" facing the clinical application of such treatment. Herein, traceable biomimetic nanoantibiotics (BioNanoCFPs) were developed by loading indacenodithieno[3,2- b ]thiophene (ITIC) and cefoperazone (CFP) in nanoplatforms coated with natural killer (NK) cell membranes. The BioNanoCFP exhibited excellent demonstrated mucus-penetrating abilities, facilitating their arrival at the infection site. The presence of Toll-like receptors in the NK cell membrane rendered the BioNanoCFP with the capability to recognize pathogen-associated molecular patterns within bacteria, allowing precise targeting of bacterial colonization sites and achieving substantial therapeutic efficacy. Overall, our findings demonstrate the viability and desirability of using NK cell membrane-mediated drug delivery as a promising strategy for precision treatment.

Fluorescent molecular platforms are highly sought after for their applications in biology and optoelectronics but face challenges with solid-state emission quenching. To address this, bulky substituents or aggregation-induced emission luminogens to restrict intramolecular motion are used to enhance the brightness. Here, we have successfully engineered a novel class of boron complexed pyrrolide salicyl-hydrazone fluorophores named BPSHY. These dyes were synthesized through a diversity-oriented condensation of pyrrole and salicylaldehyde derivatives combined with various aromatic boronic acids. The resulting 3D structures, owing to bulky boron axially substituted aryl groups, impart excellent solubility in a variety of solvents. Significantly, the BPSHY dyes exhibit strong absorption in the visible region and remarkably large Stokes shifts. Crucially, they demonstrate intense emission in aqueous solutions due to aggregation-induced emission effects. In solid-states, these dyes achieve high quantum yields, reaching up to 58%. Further expanding their utility, we developed two new BPSHY probes: one incorporating morpholine and another containing triphenylphosphine salt. Both of them are found to specifically label subcellular organelles such as lysosomes and mitochondria within live cells. Notably, these probes demonstrate exceptional staining efficacy and two-photon fluorescence feature. This highlights the considerable promise of BPSHY fluorophores for monitoring and visualizing the dynamic transformations of organelles.

A multicomponent [2+2+1] tandem cyclization of alkynones with amines and water using potassium thiocyanate as electrolyte and raw material to access thiazol-2(3 H )-ones has been developed. This transformation proceeded smoothly via electrocatalytic oxidative C-H bond thiolation, and nucleophilic cascade cyclization to build the (C-S/C-N) bonds to construct the C-O bond. The reaction avoided using transition metal catalysts or oxidation reagents, making it more sustainable and renewable.

Fatty acids play a putative role as second messengers of phytohormones and regulate the rice grain weight. However, the inner mechanism is still unclear and needs to be further studied. In this study, we identified that oleic acid (C18:1) negatively correlates while linoleic acid (C18:2) positively correlates with rice grain weight. Field trials showed that 1000-grain weight was significantly reduced when treated with the fatty acid synthesis inhibitor, Firsocostat S enantiomer (FSE), at the heading and flowering stages. RNA-seq analysis revealed that FSE affects grain weight by modulating processes, such as glycolysis, sucrose metabolism, and hormone signaling. Notably, FSE inhibited the expression of OsLIN6 , which is responsible for transporting C18:1 to the phosphatidylcholine pool for C18:2 synthesis. Compared with the wild type (WT), the OsLIN6 knockout mutant exhibited a lower grain weight, an increased C18:1 content, and a decreased C18:2 content. Importantly, OsARF12 was shown to bind to the OsLIN6 promoter and activate its expression. In summary, this study highlights the crucial role of the fatty acid synthesis gene, OsLIN6 , which was regulated by OsARF12, in rice grain weight determination, thus establishing the molecular link between fatty acid synthesis and auxin signaling.

In this study, we report a strategy for fabricating binary surface-enhanced Raman scattering (SERS) substrates composed of plasmonic Pt@Ag and Pt@Au truncated-octahedral (TOh) dual-rim nanoframes (DNFs) functioning as a "nanoalloy." Pt TOh frameworks act as a scaffold to develop nanoarchitectures with surface decoration using plasmonically active materials (i.e., Au or Ag), resulting in identical sizes and shapes for the two distinct plasmonic elements, facilitating the fabrication of a "nanoalloy" blend of two shape-complex building blocks. The structural complexity from the dual-rim on (111) facets, combined with the mirror charge effect (i.e., enhanced polarization between Ag and Au) at the interface of heterogeneous components, significantly amplifies SERS activity. We carefully investigated near-field focusing of binary SERS substrates through single-particle and bulk SERS measurements corroborated by finite element method (FEM) calculations. Crucially, we developed free-standing superpowders (SPs) in which each heterogeneous building block formed micron-sized supercrystals with adjustable component ratios. These plasmonic SPs were applied to contaminated areas for analyte detection, demonstrating their potential for practical SERS applications.

The electrochemical behavior of three types of bisphenol A polyoxyethylene ether sodium sulfate (BPA) is investigated through cyclic voltammetry striping tests. The results indicate that BPA-25 exhibited the most significant inhibition of Cu deposition. The nanotwinned Cu (nt-Cu) films are prepared by direct current electrodeposition in an acidic Cu sulfate bath containing a combination of conventional bath additives. Transmission electron microscopy (TEM) and cross-sectional scanning electron microscopy (SEM) results revealed that nt-Cu consisted of microcolumnar grains with high-density nanoscale coherent twin boundaries oriented parallel to the growth surface. The interaction between BPA-25 and the poly2-sulfur-2-propane sodium sulfonate (SPS) was further analyzed through galvanostatic measurements (GMs) and electron backscatter diffraction (EBSD). The results demonstrate that BPA-25 and SPS underwent competitive adsorption on the cathode surface, leading to the formation of nt-Cu. This growth mechanism provides a new perspective for the preparation of nt-Cu by using direct current electrodeposition.

Ulcerative colitis (UC), a chronic inflammatory bowel disease, poses a heightened colorectal cancer risk due to persistent mucosal inflammation and barrier dysfunction. In this article, a negatively charged thermosensitive hydrogel loaded with pectin microspheres was used as the enema for UC treatment. Succinic acid was immobilized on poly(ε-caprolactone- co -glycolide)-poly(ethylene glycol)-poly(ε-caprolactone- co -glycolide) (PCLGA-PEG-PCLGA) triblock copolymers to preferentially coat on cationic-inflamed sites via electrostatic interaction for reconstructing the mucosal barrier. Anti-inflammation drug 5-aminosalicylic acid (5-ASA) and curcumin-loaded pectin microspheres (Pec@Cur) were dispersed in the hydrogel for the inflammatory treatment of UC. The thermally sensitive hydrogels were rectally injected into UC model mice. The hydrogel effectively adhered to ulcers and prolonged colon retention, enabling sustained drug release and remarkably relieving the symptoms of colitis. The negatively charged hydrogel exhibited excellent significance in the UC treatment.

Target identification is crucial for elucidating the mechanisms of bioactive molecules in drug discovery. However, traditional methods assess compounds individually, making it challenging to efficiently examine multiple compounds in parallel, especially for structurally diverse compounds. This study reports a novel strategy called chemical genomics-facilitated chemical proteomics (CGCP) for multiplexing the target identification of bioactive small molecules. CGCP correlates compounds' perturbation of global transcription, or chemical genomic profiles, with their reactivity toward target proteins, enabling simultaneous identification of targets. We demonstrated the utility of CGCP by studying the targets of celastrol (Cel) and four other electrophilic compounds with varying levels of similarity to Cel based on their chemical genomic profiles. We identified multiple novel targets and binding sites shared by the compounds in a single experiment. CGCP enabled multiplexity and improved the efficiency of target identification for structurally distinct compounds, indicating its potential to accelerate drug discovery.

Growing evidence suggests that activity-dependent gene expression is crucial for neuronal plasticity and behavioral experience. Enhancer RNAs (eRNAs), a class of long noncoding RNAs, play a key role in these processes. However, eRNAs are highly dynamic and are often present at lower levels than their corresponding mRNAs, making them difficult to detect using total RNA-seq techniques. Nascent RNA sequencing, which separates nascent RNAs from the steady-state RNA population, has been shown to increase the ability to detect activity-induced eRNAs with a higher signal-to-noise ratio. However, there is a lack of bioinformatic tools or pipelines for detecting eRNAs utilizing nascent RNA-seq and other multiomics data sets. In this study, we addressed this gap by developing a novel bioinformatic framework, e-finder, for finding eRNAs and have made it available to the scientific community. Additionally, we reanalyzed our previous nascent RNA sequencing data and compared them with total RNA-seq data to identify activity-regulated RNAs in neuronal cell populations. Using H3K27 acetylome data, we characterized activity-dependent eRNAs that drive the transcriptional activity of the target genes. Our analysis identified a subset of eRNAs involved in mediating synapse organization, which showed increased activity-dependent transcription after the potassium chloride stimulation. Notably, our data suggest that nascent RNA-seq with an enriched H3K27ac signal exhibits high resolution to identify potential eRNAs in response to membrane depolarization. Our findings uncover the role of the eRNA-mediated gene activation network in neuronal systems, providing new insights into the molecular processes characterizing neurological diseases.

The application of traditional isocyanate-based polyimide (PI) foams is highly hindered due to limited flame retardancy, poor mechanical properties, and relatively single functionality. Herein, we propose an effective method to fabricate dual cross-linked polyimide/bismaleimide (PI-BMI) foams with outstanding heat resistance and enhanced mechanical properties by incorporating bis(3-ethyl-5-methyl-4-maleimidophenyl)methane (ME-BMI) as the interpenetrating network. The results show that the prepared PI-BMI composite foams exhibit enhanced mechanical properties with lightweight characteristics (23-80 kg·m -3 ). When the ME-BMI loading reached 120 wt %, the tensile and compressive strength of PI-BMI composite foam can reach 1.9 and 7.8 MPa, which are 9.6 and 63.3 times higher than that of pure PI foam, respectively. In comparison with PIF-0, the 10% heat loss temperature ( T d,10% ) of PIF-90 improved by 156 °C. Moreover, the PI-BMI foam piezoelectric sensor containing fluorine groups presents a short response time (14.22 ms), high sensitivity (0.266 V/N), and outstanding stability (10 000 cycles). Besides, the sensor can accurately monitor human activity in different states. This work provides a promising strategy for designing multifunctional PI foams, making them suitable for applications in aerospace and microelectronics.

Significant discrepancies were observed between the experiments and the simulations for ṄH 2 time-histories in monomethylhydrazine pyrolysis with the robust mechanism proposed by Pascal and Catoire. The rate of formation analyses for ṄH 2 indicated the significance of the reaction NH 2 ṄH + ṄH 2 = H 2 NN + NH 3 , which has not been well-defined. In this study , ab initio calculations were performed for the theoretical description of the NH 2 ṄH + ṄH 2 chemistry. Most stationary points on the potential energy surface were quantified at the CCSD(T)/CBS//M06-2X/aug-cc-pVTZ level, and the multireference methods were employed for barrier-less reaction and some transition states. The temperature- and pressure-dependent rate coefficients were determined using classical and microcanonical variational transition state theories. Four primary reaction channels were identified as competitive: 1) The H atom abstraction reaction yielding N 2 H 2 (T) + NH 3 , dominating at 1350-3000 K across the 0.001-100 atm pressure range. 2) The H atom abstraction reaction forming N 2 H 2 (S) + NH 3 , dominating at 800-1350 K and competing with the processes of chemical activation and collisional stabilization below 800 K. 3) The chemical-activated reaction resulting in H 2 NN(S) + NH 3 , dominating below 800 K at 0.001 atm. 4) The collisional-stabilized recombination reaction leading to N 3 H 5 , becoming significant as pressure increases and dominating below 600 and 650 K at 1 and 100 atm, respectively. The implications of newly calculated NH 2 ṄH + ṄH 2 kinetics for the monomethylhydrazine pyrolysis mechanism were evaluated, and updates were implemented. Sensitivity analyses indicated the necessity of additional research efforts to comprehend the dynamics of CH 3 NH 2 unimolecular and N 2 H 2 + ṄH 2 reaction systems. The rate coefficients presented in this study can be employed to develop the chemical kinetic model of nitryl-containing systems.

This study represents a highly sensitive and selective approach to protein screening using surface-enhanced Raman scattering (SERS) facilitated by octahedral Au nanotrenches (OANTs). OANTs are a novel class of nanoparticles characterized by narrow, trench-like excavations indented into the eight facets of a Au octahedron. This unique configuration maximizes electromagnetic near-field focusing as the gap distance decreases to ∼1 nm. Owing to geometrical characteristics of the OANTs, near-field focusing can be maximized through the confinement and reflectance of light trapped within the trenches. We used Ni ions and molecular linkers to confer selective binding affinity for His-tagged proteins on the surfaces of the OANTs for SERS-based protein screening. Remarkably, SERS-based protein screening with the surface-modified OANTs yielded outstanding screening capabilities: 100% sensitivity and 100% selectivity in distinguishing His-tagged human serum albumin (HSA) from native HSA. This highlights the significantly enhanced protein screening capabilities achieved through the synergistic combination of SERS and the OANTs.

Modern quantum device fabrication often requires precisely adding and removing materials in situ at nanoscales, which is challenging for high-quality correlated oxide devices. In this work, we present a novel nanofabrication method that remotely controls the interfacial metal-insulator transition at the LaAlO 3 /SrTiO 3 interface by selectively removing an LaAlO 3 overlayer using a diamond tip. Remarkably, we observe a large force window within which single atomic layer precision of control is achievable. Our results confirm the critical thickness and charge transfer mechanism through a layer-by-layer removal process at the interface. Additionally, high-quality nanodevices, including nanochannels and single electron transistors, are successfully fabricated using this method. This nonvolatile and high-precision nanofabrication method provides a promising oxide platform for quantum engineering by harnessing the rich electron correlations at the nanoscale.

The high toxicity and widespread contamination of ochratoxin A (OTA) make it urgent to develop a sensitive method to detect trace OTA in complex food matrices. Herein, an indirect competitive enzyme-linked immunosorbent assay (icELISA)-based on the CRISPR/Cas12a system is described. DNA amplicons with multiple activation sequences of the CRISPR/Cas12a system were pre-prepared to improve detection sensitivity. In the absence of OTA, streptavidin-mediated biotinylated DNA amplicons were captured by the biotinylated secondary antibody on the microplate. The captured DNA amplicons activated the CRISPR/Cas12a system, which thereby effectively cleaved the reporter DNA, producing strong fluorescence. The presence of OTA led to a decrease in DNA amplicons on the microplate, resulting in a decrease in activated Cas12a and ultimately a drop in fluorescence intensity. OTA in food matrices at nanogram per milliliter levels can be detected. Therefore, the new method has great potential in monitoring OTA.

In this study, we investigate the behavior of carbon clusters (C n , where n ranges from 16 to 26) supported on the surface of MgO. We consider the impact of doping with common impurities (such as Si, Mn, Ca, Fe, and Al) that are typically found in ores. Our approach combines density functional theory calculations with machine learning force field molecular dynamics simulations. It is found that the C 21 cluster, featuring a core-shell structure composed of three pentagons isolated by three hexagons, demonstrates exceptional stability on the MgO surface and behaves as an "enhanced binding agent" on MgO-doped surfaces. The molecular dynamics trajectories reveal that the stable C 21 coating on the MgO surface exhibits less mobility compared to other sizes C n clusters and the flexible graphene layer on MgO. Furthermore, this stability persists even at temperatures up to 1100K. The analysis of the electron localization function and potential function of C n on MgO reveals the high localization electron density between the central carbon of the C 21 ring and the MgO surface. This work proposes that the C 21 island serves as a superstable and less mobile precursor coating on MgO surfaces. This explanation sheds light on the experimental defects observed in graphene products, which can be attributed to the reduced mobility of carbon islands on a substrate that remains frozen and unchanged.

Overcoming intestinal epithelial barriers to enhance bioavailability is a major challenge for oral delivery systems. Desirable nanocarriers should simultaneously exhibit rapid mucus penetration and efficient epithelial uptake; however, they two generally require contradictory structural properties. Herein, we proposed a strategy to construct multiperformance nanoparticles by modifying the rigidity of amphiphilic nanostructures originating from soy polypeptides (SPNPs), where its ability to overcome multibarriers was examined from both in vitro and in vivo , using curcumin (CUR) as a model cargo. Low-rigidity SPNPs showed higher affinity to mucin and were prone to getting stuck in the mucus layer. When they reached epithelial cells, they tended to be endocytosed through the clathrin and macropinocytosis pathways and further transferred to lysosomes, showing severe degradation and lower transport of CUR. Increased particle rigidity generally improved the absorption of CUR, with medium-rigidity SPNPs bloomed maximum plasma concentration of CUR by 80.62-fold and showed the highest oral bioavailability. Results from monocultured and cocultured cell models demonstrated that medium-rigidity SPNPs were least influenced by the mucus layer and changes in rigidity significantly influenced the endocytosis and intracellular fate of SPNPs. Those with higher rigidity preferred to be endocytosed via a caveolae-mediated pathway and trafficked to the ER and Golgi, facilitating their whole transcytosis, and avoiding intracellular metabolism. Moreover, rigidity modulation efficiently induces the reversible opening of intercellular tight junctions, which synergistically improves the transport of CUR into blood circulation. This study suggested that rigidity regulation on food originated amphiphilic peptides could overcome multiple physiological barriers, showing great potential as natural building block toward oral delivery.

The advancement of acetylcholinesterase (AChE) activity and its inhibitor assays is crucial for clinical diagnosis, drug screening, and environmental monitoring. A nanozyme-mediated cascade reaction system could offer promising prospects for a wide range of applications in such biosensing; however, the creation of nanozyme catalysts with diverse functionalities remains a significant challenge. Herein, we have proposed a multifunctional iron-doped polymer dots (Fe-PDs) nanozyme possessing excellent fluorescence and peroxidase (POD)-mimicking activity. Notably, the Fe-PDs nanozyme is capable of catalyzing H 2 O 2 to produce a series of reactive oxygen species, which can simultaneously quench the fluorescence of Fe-PDs and induce a chromogenic reaction of 3,3',5,5'-tetramethylbenzidine (TMB), enabling the dual-mode detection of H 2 O 2 through both fluorescence turn-off and absorbance turn-on signals. Furthermore, by integrating acetylcholine (ACh) and choline oxidase (ChOx), we have developed a three-enzyme (AChE-ChOx-POD) cascade-based fluorometric and colorimetric dual-mode sensing platform for monitoring AChE activity and its inhibitors. The sensitive and convenient dual-mode sensor has achieved low limits of detection with 0.5 mU/mL (fluorometry) and 0.014 mU/mL (colorimetry) for AChE, respectively, which are superior to the traditional Ellman's assay. More significantly, this sensor can also be extended to detect the reversible and irreversible inhibitors of AChE, such as tacrine (IC 50 = 23.3 nM) and carbaryl (LOD = 0.8 nM). We firmly believe that this innovative dual-mode nanozyme-involved multienzyme cascade system-based sensing strategy will stimulate further exploration and serve as a versatile and practical tool for biochemical sensing applications.

It is important to obtain the configuration of polypeptides and the sequence information on amino acids for understanding various life processes and many biological applications. Nanopores, as a newly developed single-molecule detection technology, exhibit unique advantages in real-time dynamics detection. Here, we designed a special peptide chain with 10 arginine in the head and achieved successful single-molecule detection by ultrasmall solid-state nanopores (2-3 nm). Unique bidirectional translocation signals were observed and explained under the framework of charge distribution of the peptide and interaction with the nanopore wall. Two natural peptide chains, histatin-5 and angiopep-2, were also explored by nanopore experiments to confirm our conjecture. Our designed peptide chain could realize multiple detections of the same peptide chain, offering possibilities for high-resolution peptide detection and fingerprinting by solid-state nanopores in the future.

The Keggin-Al 13 hydroxide clusters serve as pivotal models for elucidating molecular pathways in geochemical reactions. In this study, we presented a strategy aiming at the quantitative detection of ε-Al 13 Keggin clusters using photoluminescent spectra. Specifically, we manipulate the electronic structure of ε-Al 13 by introducing Na ions onto the ε-Al 13 surface, encapsulated within a Na-O 3 motif. The Na-ion-modified ε-Al 13 (Na-ε-Al 13 ) cluster demonstrates incredible photoluminescent qualities, with fluorescence excitation and emission peaks centered at 365 and 436 nm, respectively. In addition, the fluorescence intensities display a linear dependence on the concentrations of Na-ε-Al 13 , with a detection limit of 15.4 μM. This correlation facilitates the quantitative and precise determination of Na-ε-Al 13 concentrations via fluorescence. Both experimental characterizations and theoretical calculations underscore the importance of decorated Na ions in regulating the electronic structure of the ε-Al 13 cluster. Lastly, the influence of external anions/cations on the photoluminescent properties of ε-Al 13 primarily mirrors modifications to the nonradiative decay process, which is regulated via electrostatic interactions. This work demonstrates an effective strategy for quantitative detection of the ε-Al 13 Keggin clusters through photoluminescent spectra.

Owing to their outstanding optoelectronic properties, halide perovskite (HP) materials have been employed in a wide range of applications, including solar cells, light-emitting devices, and X-ray detectors. Among them, lead-free double HPs are characterized by enhanced stability and reduced toxicity compared with lead-based alternatives. Cs 2 AgBiBr 6 , in particular, has emerged as a promising candidate for direct X-ray detection. The detection sensitivity, on the other hand, cannot yet compete with that of lead-containing perovskites. Developing schemes to improve X-ray detection efficiency is critical for reducing radiation exposure in medical imaging applications. Here, we investigate the potential of controlled doping and cation substitution with either lanthanides or small organic cations to improve the X-ray detection performance of Cs 2 AgBiBr 6 . Our findings reveal that by growing the perovskite in a slightly Bi-poor and Eu-rich environment, the X-ray sensitivity significantly increases 7-fold (from 17 to 120 μC Gy air -1 cm -2 ) and simultaneously improves the phototo-dark current ratio (from 2.5 to 29). Additionally, Cs-site substitution with imidazolium remarkably enhances the sensitivity over 10-fold (180 μC Gy air -1 cm -2 ), and ammonium enhances the phototo-dark current ratio to 37. Terahertz photoconductivity measurements reveal a positive correlation between enhanced X-ray sensitivity and improved charge transport properties (e.g., increased scattering time and, thus, carrier mobility) by doping. This study outlines straightforward strategies for boosting X-ray detection and fundamental photoconductivity in lead-free double HP, with potential implications for broader optoelectronic applications., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

FA-MA-Cs ternary cation perovskite exhibits excellent optoelectronic properties and high stabilities against humidity and light soaking and thus has aroused extensive attention in polycrystalline thin film solar cells. Compared with polycrystalline counterparts, FA-MA-Cs ternary cation perovskite single-crystal thin films (SCTFs) have lower defects, better carrier transport capacity, and stability because of lacking grain boundary defects. However, the immature growth technology of SCTFs restricts digging out its optoelectronic potential. Here, we proposed an improved space-confined method to grow large area FA 0.9 MA 0.05 Cs 0.05 PbI 2.7 Br 0.3 SCTFs using a tunable heating area to control the nucleation and growth process. Its area reaches 64 mm 2 with a thickness of 26 μm. The SCTF exhibits high crystallinity, low defect density, long carrier lifetime, and high moisture resistance stability. Besides, a photosensitive chip based on a planar metal-semiconductor-metal photodetector demonstrates linear response to the three primary colors, with a photosensitive range that is 1.5 times that of protocol 3 wide color gamut. Under high-frequency light sources, the on/off ratio reaches 3.9 × 10 3 , and the response time can be as low as 400 ns. Such ultrafast response speed and broad photosensitive range are successfully achieved for imaging applications.

Lithium-sulfur (Li-S) batteries are considered as promising energy storage systems due to the high energy density of 2600 W h kg -1 . However, the practical application of Li-S batteries is hindered by the inadequate conductivity of sulfur and Li 2 S, as well as the shuttle effect caused by polysulfides during the charge-discharge process. Introducing a conductive interlayer between the cathode and the separator to physically resist polysulfides represents an effective and straightforward approach to mitigate the shuttle effect in Li-S batteries. In this paper, an ultrathin (<1 μm) 2D-2D MXene-LDH interlayer with high polysulfide adsorption ability was introduced to Li-S batteries. The synergistic effect between MXene and layered double hydroxide greatly improved the adsorption effect of the interlayers: the conductive Ti 3 C 2 T x MXene chemically adsorbs polysulfides and promotes their fast transfer, and the NiCo-LDH alleviates the restack of MXene and facilitates Li + diffusion. After inserting the MXene-LDH interlayer, the Li-S batteries exhibit an enhanced specific capacity of 1137.6 mA h g -1 at 0.1 C and retain 622.6 mA h g -1 after 100 cycles. The ultrathin 2D-2D interlayer offers a feasible way for the development of highly efficient and lightweight interlayers in Li-S batteries.

Geranylgeraniol (GGOH) is a crucial component in fragrances and essential oils, and a valuable precursor of vitamin E. It is primarily extracted from the oleoresin of Bixa orellana , but is challenged by long plant growth cycles, severe environmental pollution, and low extraction efficiency. Chemically synthesized GGOH typically comprises a mix of isomers, making the separation process both challenging and costly. Advancements in synthetic biology have enabled the construction of microbial cell factories for GGOH production. In this study, Yarrowia lipolytica was engineered to efficiently synthesize GGOH by expressing heterologous phosphatase genes, enhancing precursor supplies of farnesyl diphosphate, geranylgeranyl pyrophosphate, and acetyl-CoA, and downregulating the squalene synthesis pathway by promoter engineering. Additionally, optimizing fermentation conditions and reducing reactive oxygen species significantly increased the GGOH titer to 3346.47 mg/L in a shake flask. To the best of our knowledge, this is the highest reported GGOH titer in shaking flasks to date, setting a new benchmark for terpenoid production.

High-nickel (Ni ≥ 90%) cathodes which have a high specific capacity hold great potential for next-generation lithium-ion batteries (LIBs). However, their practical application is restricted by their high interfacial reactivity because of the presence of residual lithium (Li) compounds on the surface. Herein, the LiNi 0.9 Co 0.06 Mn 0.04 O 2 (NCM90) cathode is surface-modified with sulfur (S) via a simple and feasible dry mixing and low-temperature heat treatment, converting the residual lithium compound on the surface into inactive lithium sulfate (Li 2 SO 4 ). This induces the formation of a stable inorganic enriched electrode-electrolyte interface on the cathode surface and inhibits the occurrence of side reactions, ultimately inhibiting lattice collapse and the dissolution of transition metal ions. After modifying, the capacity retention rates of NCM90/Li and NCM90/graphite cells are both greatly enhanced after long cycling. This work provides a new idea for the rational design of the electrode-electrolyte interface of high-nickel cathodes.

Gene therapy has emerged as a potent tool for treating a wide range of hereditary and acquired disorders. However, the development of high-performance nonviral gene delivery vectors remains a significant challenge. Here we report the development of a new type of star-shaped poly(β-amino ester) (SPAE) through a "top-down" hydrolysis approach and demonstrate its exceptional DNA transfection efficiency and safety profiles. Two SPAEs with different monomer combinations are first synthesized using an "arm first" strategy and then hydrolyzed sequentially to produce h-SPAEs with varied chemical compositions and molecular weights. Results demonstrate that hydrolysis significantly influences the physiological characteristics of the resulting h-SPAEs and h-SPAE/DNA polyplexes. Dependent on the chemical composition, h-SPAEs with low to moderate hydrolysis degrees exhibit superior gene transfection efficiency and cell viability across various cell types. Notably, the leading candidate, h-SPAE-1-5h, achieves up to 88.8% gene transfection efficiency, which was 154-257% higher compared to SPAE-1. This study not only establishes an easy-to-operate "top-down" approach for reshaping the topological structure and chemical composition of SPAEs, but also identifies promising candidates for effective gene transfection. This strategy can be applied to other cationic polymers to enhance their gene transfection performance.

The primary objective within the realm of aluminum solution chemistry is to elucidate the structural changes in aluminum polyoxocations under the influence of altered solution conditions. Notably, previous reports are primarily focused on specific types, such as aluminum monomers, species from the Keggin series, and the planar Flat-Al 13 15+ (F-Al 13 ) cluster. As a result, there is a lack of comprehensive understanding of the remaining aluminum polyoxocations and their respective transformation pathways. In response to this lack, we adopt a combined experimental and theoretical approach to explore the spectral properties of aluminum polyoxocations. Specifically, we analyze infrared spectra, Raman spectra, and aluminum-27 nuclear magnetic resonance ( 27 Al NMR) spectra. Notably, the changes in the spectral features originate from varying solution basicity levels. Through our findings, we can categorize the Al-O clusters into three primary groups: Al(H 2 O) 6 3+ (Al 1 ), ε-Keggin-[AlO 4 Al 12 (OH) 24 (H 2 O) 12 ] 7+ (ε-Al 13 ), and 6-coordinated aluminum species. Notably, the Raman spectra exhibit prominent peak shifts at 559 and 595 cm -1 , indicating the existence of Al 3 (1) intermediates during the transition from the Al monomer to the ε-Al 13 cluster. Overall, this paper presents a comprehensive summary of the possible mechanisms that govern the formation of ε-Al 13 from Al 3 (1), offering a clearer picture of the aluminum polyoxocation landscape and its dynamics under various solution conditions.

Penicillium daleae L3SO is a fungus isolated from the rhizospheric soil of the chloroplast-deficient plant Monotropa uniflora . A chemical study on the rice fermentation of this fungus led to the isolation and identification of two cage-like polyketides, penidaleodiolide A ( 1 ) and its biosynthetic-related congener penidaleodiolide B ( 2 ). The structures of 1 and 2 were determined by a combination of extensive spectroscopic analysis, biosynthetic consideration, chemical derivatization, and computational methods. Compound 1 harbors an unusual tricyclo[4.3.0 4,9 ]nonane scaffold, unprecedented in polyketide natural products. The hypothetical biosynthetic pathways for 1 and 2 were postulated and were supported by CRISPR/Cas9 genome editing results. Penidaleodiolide A ( 1 ) showed a significant inhibitory effect on the action potentials of murine hippocampal basket neurons and decreased the frequency of spontaneous excitatory postsynaptic currents in a concentration-dependent manner (the inhibition ratios were 0.30 ± 0.02 for 1 μM, 0.37 ± 0.03 for 10 μM, and 0.50 ± 0.07 for 20 μM) while being devoid of cytotoxicity against the nerve cells.

Nonradiative charge recombination, originating from defects, limits the use of semiconductors in solar energy conversion technologies. Defect passivation is an effective approach to eliminating charge recombination centers. Focusing on InSe semiconductor, we have shown that the adsorption configurations of passivators have a strong impact on the defect passivation, using nonadiabatic molecular dynamics combined with time-dependent density functional theory. The simulations demonstrate that the physisorption passivator cannot eliminate the recombination centers, resulting in fast nonradiative charge recombination. By contrast, the chemisorption passivators are able to form covalent bonds with indium, remove the charge recombination centers, thereby prolonging the charge recombination time by more than a factor of 10 because of the decreased nonadiabatic coupling and channels for charge and energy losses. This study uncovers the microscopic effects of the adsorption configurations of passivators on the photogenerated charge carrier dynamics, suggesting that chemisorption passivators are essential for defect passivation.

Herein, we propose a platinization strategy for the preparation of Pt/X catalysts with low Pt content on substrates possessing electron-rich sites (Pt/X: X = Co 3 O 4 , NiO, CeO 2 , Covalent Organic Framework (COF), etc.). In examples with inorganic and organic substrates, respectively, Pt/Co 3 O 4 possesses remarkable catalytic ability toward HER, achieving a current density at an overpotential of 500 mV that is 3.22 times higher than that of commercial Pt/C. It was also confirmed by using operando Raman spectroscopy that the enhancement of catalytic activity was achieved after platinization of the COF, with a reduction of overpotential from 231 to 23 mV at 10 mA cm -2 . Density functional theory (DFT) reveals that the improved catalytic activity of Pt/Co 3 O 4 and Pt/COF originated from the re-modulation of Pt δ+ on the electronic structure and the synergistic effect of the interfacial Pt δ+ /electron-rich sites. This work provides a rapid synthesis strategy for the synthesis of low-content Pt catalysts for electrocatalytic hydrogen production.

Vanillin (VAN) is a common flavoring agent that can cause liver damage when ingested in large amounts. Nevertheless, the precise processes responsible for its toxicity remain obscure. The present research aimed to examine the metabolic activation of VAN and establish a potential correlation between its reactive metabolites and its cytotoxicity. In rat liver microsomes incubated with VAN, reduced glutathione/ N -acetylcysteine (GSH/NAC), and nicotinamide adenine dinucleotide phosphate (NADPH), two conjugates formed from GSH and one conjugate derived from NAC were identified. We also discovered one GSH conjugate in both the bile obtained from rats and the rat primary hepatocytes that were subjected to VAN exposure. Additionally, the NAC conjugate exerted in the urine of VAN-treated rats was observed. These results indicate that a quinone intermediate was produced from VAN both in vitro and in vivo . Next, we identified CYP3A as the main enzyme that initiated the bioactive pathway of VAN. After the activity of CYP3A was selectively inhibited by ketoconazole (KTZ), the generation of the GSH conjugate declined in hepatocytes exposed to VAN. Furthermore, the vulnerability to VAN-induced toxicity was alleviated by KTZ in hepatocytes. Thus, we propose that the cytotoxicity of VAN may derive from metabolic activation triggered by CYP3A.

We disclose a rapid and nontoxic procedure to construct various oxindoles. This method harnesses the power of a catalytic amount of quinone in synergy with Cs 2 CO 3 , showcasing remarkable compatibility with a wide range of functional groups. Mechanistic investigations reveal that it operates via a radical pathway, likely initiated by the single-electron transfer from quinone-Cs 2 CO 3 complexes. This pivotal electron transfer event leads to the generation of a crucial alkyl radical intermediate, contributing to the overall success and efficacy of the transformation.

Effective design and engineering of catalysts for an optimal performance depend extensively on a profound understanding of the intricate catalytic dynamics under reaction conditions. In this work, we showcase rapid freeze-quench (RFQ) Mössbauer spectroscopy as a powerful technique for quantitatively monitoring the catalytic dynamics of single-Cu-atom-modified SnS 2 (Cu 1 /SnS 2 ) in the electrochemical CO 2 reduction reaction (CO 2 RR). Utilizing the newly established RFQ 119 Sn Mössbauer methodology, we clearly identified the dynamic transformation of Cu 1 /SnS 2 to Cu 1 /SnS and Cu 1 /Sn during the CO 2 RR, resulting in an outstanding Faradaic efficiency for formate production (∼90.9%) with a partial current density of 158 mA cm -2 . Results from operando Raman spectroscopy, operando attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), quasi in situ electron microscopy, and quasi in situ X-ray photoelectron spectroscopy (XPS) measurements indicate that the anchored single Cu atom in Cu 1 /SnS 2 can accelerate the reduction of SnS with in situ formation of Cu 1 /Sn under CO 2 RR conditions, which effectively promote the generation of *CO 2 - /*OCHO intermediates. Theoretical calculations further support that in situ formed Cu 1 /Sn works as active sites catalyzing the CO 2 RR, which reduces the energy barrier for the CO 2 activation and formation of the *OCHO intermediate, thereby facilitating the conversion of CO 2 to formate. The results of this work provide a thorough understanding of the dynamic evolution of Sn-based catalytic sites in the CO 2 RR and shed light for engineering single atoms with an optimized catalytic performance. We anticipate that RFQ Mössbauer spectroscopy will emerge as an advanced spectroscopic technique for enabling a genuine visualization of catalytic dynamics across various reaction systems.