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Nanosecond time-resolved resonance Raman spectra of the triplet state of 4-dimethylaminobenzonitrile (DMABN), DMABN-d6 and DMABN-N15 are investigated over the frequency range from 700 to 2300 per cm. Spectral results obtained in polar and nonpolar solvents suggest that the lowest triplet state T(sub 1)(super 3) state has only one form, having planer structure with a high negative charge localization on the cyano group, and a substantial loosening of the ring skeleton with conjugation extending to the amino group.

The crystallization of α-p-aminobenzoic acid (pABA) from mixed solutions in ethanol (EtOH) and nitromethane (NMe) is reported. From solutions with compositions >60 wt % NMe, the known α-polymorph of pABA appears. In contrast, crystals prepared from mixed solvent with <60 wt % NMe reveal the presence of a previously unknown NMe solvate, which crystallizes concomitantly with the α-form. The crystal structure of this new form has been determined and is compared with the previously known structure of the α-polymorph. The crystal structure of the NMe solvate has similar synthonic interactions with respect to α-pABA, in particular, the OH···O H-bonded dimers and the NH···O H-bonds between the pABA molecules. However, the π-π stacking interactions between the phenyl ring groups are found to be much more offset and do not form a continuous chain through the structure, as found in α-pABA. The synthonic interactions in the NMe solvate structure are generally weaker than those found in α-pABA, and the lattice energy is calculated to be significantly lower, suggesting the solvate structure is metastable with respect to α-pABA. The impact of NMe on the morphology of α-pABA crystals, together with molecular modelling results suggest that this solvent is able to disrupt the π-π stacking interactions that dominate growth along the needle (b-axis) direction of α-pABA, and are intimately linked to the ultimate formation of the solvate. [ABSTRACT FROM AUTHOR]

We report an investigation of the adhesive force generated between the hydrophobic tip of an atomic force microscope (AFM) and surfaces presenting oligopeptides immobilized using either short (~1 nm) or long (~60 nm) tethers. Specifically, we used either sulfosuccinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SSMCC) or 10 kDa polyethylene glycol (PEG) end-functionalized with maleimide and N-hydroxysuccinimide groups to immobilize helical oligomers of β-amino acids (β-peptides) to mixed monolayers presenting tetraethylene glycol (EG4) and amine-terminated EG4 (EG4N) groups. When SSMCC was used to immobilize the β-peptides, we measured the adhesive interaction between the AFM tip and surface to rupture through a single event with magnitude consistent with the interaction of a single β-peptide with the AFM tip. Surprisingly, this occurred even when, on average, multiple β-peptides were located within the interaction area between the AFM tip and surface. In contrast, when using the long 10 kDa PEG tether, we observed the magnitude of the adhesive interaction as well as the dynamics of the rupture events to unmask the presence of the multiple β-peptides within the interaction area. To provide insight into these observations, we formulated a simple mechanical model of the interaction of the AFM tip with the immobilized β-peptides and used the model to demonstrate that adhesion measurements performed using short tethers (but not long tethers) are dominated by the interaction of single β-peptides because (i) the mechanical properties of the short tether are highly nonlinear, thus causing one β-peptide to dominate the adhesion force at the point of rupture, and (ii) the AFM cantilever is mechanically unstable following the rupture of the adhesive interaction with a single β-peptide. Overall, our study reveals that short tethers offer the basis of an approach that facilitates measurement of adhesive interactions with single molecules presented at surfaces. [ABSTRACT FROM AUTHOR]

For the first time, the picosecond time-resolved resonance Raman spectrum of the intramolecular charge-transfer state of 4-dimethylaminobenzonitrile in a polar solvent has been obtained. Results are discussed and placed in context of previous work on this molecular system.

We report that specific anions (of sodium salts) addedto aqueousphases at molar concentrations can trigger rapid, orientational orderingtransitions in water-immiscible, thermotropic liquid crystals (LCs;e.g., nematic phase of 4′-pentyl-4-cyanobiphenyl, 5CB) contactingthe aqueous phases. Anions classified as chaotropic, specificallyiodide, perchlorate, and thiocyanate, cause 5CB to undergo continuous,concentration-dependent transitions from planar to homeotropic (perpendicular)orientations at LC–aqueous interfaces within 20 s of additionof the anions. In contrast, anions classified as relatively more kosmotropicin nature (fluoride, sulfate, phosphate, acetate, chloride, nitrate,bromide, and chlorate) do not perturb the LC orientation from thatobserved without added salts (i.e., planar orientation). Surface pressure–areaisotherms of Langmuir films of 5CB supported on aqueous salt solutionsreveal ion-specific effects ranking in a manner similar to the LCordering transitions. Specifically, chaotropic salts stabilized monolayersof 5CB to higher surface pressures and areal densities (12.6 mN/mat 27 Å2/molecule for NaClO4) and thussmaller molecular tilt angles (30° from the surface normal forNaClO4) than kosmotropic salts (5.0 mN/m at 38 Å2/molecule with a corresponding tilt angle of 53° forNaCl). These results and others reported herein suggest that anion-specificinteractions with 5CB monolayers lead to bulk LC ordering transitions.Support for the proposition that these ion-specific interactions involvethe nitrile group was obtained by using a second LC with nitrile groups(E7; ion-specific effects similar to 5CB were observed) and a thirdLC with fluorine-substituted aromatic groups (TL205; weak dipole andno ion-specific effects were measured). Finally, we also establishthat anion-induced orientational transitions in micrometer-thick LCfilms involve a change in the easy axis of the LC. Overall, theseresults provide new insights into ionic phenomena occurring at LC–aqueousinterfaces, and reveal that the long-range ordering of LC oils canamplify ion-specific interactions at these interfaces into macroscopicordering transitions. [ABSTRACT FROM AUTHOR]

6-Amino-5-nitropyridin-2-ol (Z), a nitroaromatic compound and a base for Hachimoji nucleic acids, holds significant potential in expanding the genetic alphabet, as well as in synthetic biology and biotechnology. Despite its promising applications, the spectral characterization and photoinduced properties of Z have remained largely unexplored until now. This study presents a comprehensive investigation into its excited state dynamics in various solvents, utilizing state-of-the-art ultrafast broadband time-resolved fluorescence and transient absorption spectroscopy, complemented by computational methods. The acquired results provide direct experimental evidence that, upon photoexcitation, Z emits prompt fluorescence from a nearly planar structure in its excited state, independent of solvent properties. This state deactivates nonradiatively within sub-picoseconds through internal conversion with a unitary yield, primarily mediated by the rotation of the nitro group. This unusually rapid deactivation pathway entirely excludes the involvement of long-lived nπ* states, triplet states, and photoproducts, which are commonly observed in most nitroaromatic compounds and natural DNA and RNA bases. Our findings underscore that Z, as an unnatural base, exhibits superior photostability compared to canonical natural bases. This provides valuable insights into the photodynamics of nitroaromatic compounds, which is beneficial for strategic substitution design in environmental and biological applications.

The sustainable and affordable environmental application of Pd catalysis needs further improvement of Pd mass activity. Besides the well-recognized importance of physical utilization efficiency─the ratio of surface atoms forming reactant-accessible reactive sites─a lesser-known fact is that the congestion of these reactive sites, which we term as the chemical utilization efficiency, also influences the mass activity. Herein, by leveraging the 100% physical utilization efficiency of a fully exposed Pd cluster (Pd n ) and the hydrogenation activity of TiNiN, we developed Pd n /TiNiN as a high physical and chemical utilization efficiency catalyst. During the catalytic hydrodechlorination of 4-chlorophenol and the subsequent hydrogenation of phenol, Pd n focuses on H 2 dissociation and C-Cl cleavage, while TiNiN facilitates the subsequent hydrogenation of phenol into less toxic cyclohexanone via H-spillover. This synergy results in a 20-40-fold increase in the hydrodechlorination rate. The enhanced chemical utilization efficiency of Pd informs the design of Pd n /TiNiN microspheres for the conversion of halogenated organics from pharmaceutical wastewater and the design of a fixed-bed reactor to transfer trace amounts of 4-CP from river water. Ultimately, this approach decentralizes the use of Pd in environmental catalysis and reduction processes.

Rare earth elements (REEs), vital and limited resources, also play a significant role in agriculture. Previous findings indicated that the proper concentration of REEs could enhance the germination process, seed germination rate, and seedling growth and development. This paper introduces designing, synthesizing, and assembling a new type of tapered nanogates for separating and detecting lanthanide ions (La 3+ ). A phosphoric acid pillar[5]arene (PP5) was synthesized and incorporated as a receptor molecule for La 3+ in aqueous media. Incorporating these receptor molecules into the nanogates enhances the identification and controlled release of the lanthanide ions in water. The UV titration and COMSOL simulation results demonstrated an interaction between PP5 and La 3+ to strengthen the understanding of the release mechanism. Finally, the effect of released La 3+ on the germination of wheat seeds is discussed, demonstrating the ability to improve its application in the agricultural industry.

The incidence of cervical cancer caused by human papillomavirus (HPV) infection has increased in recent years. More than half of all cervical cancer cases are due to HPV16 and HPV18 infection, so HPV16 and HPV18 testing is essential to prevent cervical cancer. HPV testing is mainly carried out in hospitals, but it is subject to time and specialized medical facilities. On the other hand, home self-testing using simple diagnostics would present an attractive alternative due to privacy and flexibility with regard to time and place, provided sufficient sensitivity and specificity can be achieved. In this work, a dual lateral flow assay based on RPA-CRISPR-Cas12a/13a (named RC-LFA) for HPV detection was described. Taking advantage of the cleavage specificity of Cas12a and Cas13a, a CRISPR-Cas12a/Cas13a system was designed to detect HPV16 and HPV18. The lateral flow strip with two test lines was designed to suit the CRISPR-Cas12a/Cas13 system. RC-LFA achieves rapid and simultaneous detection of HPV16 and HPV18 with high specificity and sensitivity (10 copies/μL) in about 40 min from the extraction of nucleic acid to an instrument-free readout. RC-LFA is user-friendly and instrument-free, making it a promising method for HPV self-tests at home.

Excess intrinsic Ge vacancies in GeTe materials lead to excessively high hole concentration and high thermal conductivity, producing poor thermoelectric performance. Here, synergistic control and optimization of the thermoelectric transport properties and microstructure of GeTe-based materials were achieved through co-doping with In and rare earth element Y, resulting in a significant enhancement of thermoelectric performance. The Ge 0.94 In 0.03 Y 0.03 Te sample reached a ZT max of 1.84 at 773 K, representing an increase of around 91% compared to the GeTe matrix. The experimental results indicate that the doping of In optimizes the band structure by introducing resonant levels and increasing the degeneracy of the valence band. Y doping introduces in situ nanoscale secondary phases and lattice distortions due to defect generation, enhancing phonon scattering and significantly reducing the κ lat . This work elaborates on how co-doping with In and Y achieves the optimization of the thermoelectric performance of GeTe-based materials. While the electrical transmission characteristics are improved, the thermal conductivity is significantly reduced. For the Ge 0.94 In 0.03 Y 0.03 Te sample, κ lat decreased to ∼0.56 W m -1 K -1 at 573 K, resulting in a ZT ave of ∼0.99 over the entire temperature range, representing over 140% improvement compared to undoped GeTe. This improvement is significantly higher compared with other works on GeTe and PbTe.

The self-assembled monolayer (SAM) technique, known for its customizable molecular segments and active end groups, is widely recognized as a powerful tool for regulating the interfacial properties of high-energy-density lithium metal batteries. However, it remains unclear how the degree of long-range order in SAMs affects the solid electrolyte interphase (SEI). In this study, we precisely controlled the hydrolysis of silanes to construct monolayers with varying degrees of long-range order and investigated their effects on the SEI nanostructure and lithium anode performance. The results indicate that the degree of long-range order in SAMs significantly influences the decomposition kinetics of the carbon-fluorine bond in lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), promoting the formation of a LiF-rich SEI and profoundly affecting the long-term stability of the highly sensitive anode during electrochemical processes. These findings provide new insights and directions for the molecular design of SAMs tailored for long-lasting lithium metal interfaces.

BPA, a typical endocrine disruptor, poses a significant threat to the growth of crops and thereby jeopardizes sustainable agriculture products and human health. In this work, a water-stabilized imine covalent organic framework (TpBD-COF) packed nanochannel membrane was constructed. The TpBD-COF membrane achieves high selective removal of BPA attributed to the subdivision of the pores by the filled COF, which further reduces the porous size and effectively eliminates the distance barrier between the selective sites of TpBD-COF membranes and BPA. The selective removal ratio of BPA was 5.79 times higher than that of the bare membrane, while the removal capacity reached 6.78 nM cm -2 min -1 . It can eliminate BPA from irrigation wastewater and ensure crop growth. The application of COF-filled nanoporous membrane provides not only a size-matching strategy for the development of specific continuous removal of BPA but also a theoretical reference for membrane removal of other organic pollutants in agricultural irrigation water environment.

Membrane fusion is the basis for many biological processes, which holds promise in biomedical applications including the creation of engineered hybrid cells and cell membrane functionalization. Extensive research efforts, including investigations into DNA zippers and carbon nanotubes, have been dedicated to the development of membrane fusion strategies inspired by natural SNARE proteins; nevertheless, achieving a delicate balance between membrane selectivity and high fusion efficiency through precise molecular engineering remains unclear. In our recent study, we successfully designed L-MMBen, a cationic helical antimicrobial peptide that exhibits remarkable antimicrobial efficacy while demonstrating moderate cytotoxicity. In this work, we demonstrate the effective and selective induction of fusion between phosphatidylglycerol (PG)-containing membranes by L-MMBen. By combining biophysical assays at the single-vesicle level with computer simulations at the molecular level, we discovered that L-MMBen can stably adsorb onto the surface of PG-containing membranes, leading to the formation of stalk structures between vesicles and ultimately resulting in membrane fusion. Furthermore, the occurrence of fusion is attributed to the unique ability of L-MMBen to recruit PG lipids and bridge adjacent vesicles. In contrast, its nonhelical counterpart DL-MMBen was found to lack this capability despite possessing an identical positive charge. These findings present an alternative molecule for achieving selective membrane fusion and provide insights for designing helical peptides with diverse applications.

Theranostics, by integrating diagnosis and therapy on a single platform, enables real-time monitoring of tumors during treatment. To improve the accuracy of tumor diagnosis, the fluorescence and photoacoustic imaging modalities can complement each other to achieve high resolution and a deep penetration depth. Despite the superior performance, the biodegradability of theranostic agents plays a critical role in enhancing nanoparticle excretion and reducing chronic toxicity, which is essential for clinical applications. Herein, we synthesize biocompatible and biodegradable indocyanine green (ICG)-conjugated germanium nanoparticles (GeNPs) and investigate their biodistributions in nude mice and 4T1 tumor models after intravenous injections using near-infrared (NIR) dual-modality fluorescence and photoacoustic imaging. The ICG-conjugated GeNPs have strong NIR absorption due to the NIR-absorbing ICG and Ge in combination, emit strong NIR fluorescence due to the multilayered ICG coatings, and exhibit very low in vitro and in vivo toxicity. After tail vein injections, the ICG-conjugated GeNPs mainly accumulate in the liver and spleen as well as the tumor with the help of the enhanced permeability and retention effect. The tumor's fluorescence signal is much stronger than that of the control group injected with pure ICG solution, as the GeNPs can function as biodegradable carriers for efficiently delivering the ICG molecules to the tumor. Lastly, the ICG-conjugated GeNPs accumulated in the tumor can also be utilized for photothermal treatment under NIR laser irradiation, after which the tumor volume almost diminishes after 14 days. The experimental findings in this work demonstrate that the ICG-conjugated GeNPs are promising theranostic agents with exceptional biodegradability for in vivo NIR dual-modality imaging and photothermal therapy.

Hafnium-based binary oxides are essential for fabricating nanoscale high-density ferroelectric memory devices. However, effective strategies to control and improve their thin-film single crystallinity and metastable ferroelectricity remain elusive, hindering potential applications. Here, using NdGaO 3 (NGO) substrates with four crystalline orientations, we report a systematic study of the structural characterizations and ferroelectric properties of epitaxial Hf 0.5 Zr 0.5 O 2 (HZO) films, demonstrating orientation-controlled high crystallinity and enhanced ferroelectric properties. HZO films grown on NGO(001) and NGO(110) substrates exhibit relatively low crystallinity and a significant presence of the monoclinic phase. In contrast, HZO films grown on NGO(100) and NGO(010) possess high single crystallinity and a dominant ferroelectric phase. These differences are attributed to the surface symmetry of the NGO substrate, which favors the formation of 4- or 2-fold domain configurations. Moreover, the optimized HZO films exhibit a large polarization (2 P r ) of ∼50 μC/cm 2 , enhanced fatigue behavior up to 10 11 cycles, improved retention of 2 P r ∼ 40 μC/cm 2 after 10 years, and characteristic polarization switching speeds in the submicrosecond range. Our results highlight the importance of modulating the single crystallinity and ferroelectric phase fraction of HfO 2 -based films to enhance ferroelectric properties, further revealing the potential of epitaxial symmetry engineering.

Electrode material stability is crucial for the development of next-generation ultralong-lifetime batteries. However, current solid- and liquid-state electrode materials face challenges such as rigid atomic structure collapse and uncontrolled species migration, respectively, which contradict the theoretical requirements for ultralong operation lifetimes. Herein, we present a design concept for a soft colloid polyvinylpyrrolidone iodine (PVP-I) electrode, leveraging the inherent water molecule competition effect between (SO 4 ) 2- from the electrolyte and PVP-I from the cathode in an aqueous Zn||PVP-I battery. Electrochemical demonstrations measured under various simulated and practical (integrated with photovoltaic solar panel) conditions highlight the potential for an ultralong battery lifetime. The PVP-I colloid exhibits a dynamic response to the electric field during battery operation. More importantly, the water competition effect between (SO 4 ) 2- from the electrolyte and water-soluble polymer cathode materials establishes a new electrolyte/cathode interfacial design platform for advancing ultralong-lifetime aqueous batteries.

Copper (Cu) has been considered as the most promising catalyst for the electrochemical conversion of CO 2 to multicarbon (C 2+ ) products. However, insufficient coverage of the *CO intermediate on the C 2+ formation Cu(100) facet largely hinders the C-C coupling process and thus the C 2+ conversion efficiency. Herein, we developed an epitaxial growth strategy to generate highly tensile-strained Cu(100) facets via the epitaxial growth of hexagonal boron nitride (hBN) on Cu(100) facets to promote *CO coverage for efficient CO 2 to C 2+ conversion. The highest ∼6% tensile strain on the Cu(100) facets was obtained by lattice mismatch between the Cu(100) and hBN(002) facets. Theory calculations indicated that tensile-strained Cu(100) facets deliver a notable d -band center upshift to enhance *CO adsorption. As a result, the obtained highly tensile-strained Cu(100) facets enabled an 8-fold improvement of *CO coverage and thus a 83.4% C 2+ Faradaic efficiency at 1.2 A cm -2 in strongly acidic electrolyte (pH = 1).

Short-range-ordered minerals like ferrihydrite often bind substantial organic carbon (OC), which can be altered if the minerals transform. Such mineral transformations can be catalyzed by aqueous Fe(II) (Fe(II) aq ) in redox-dynamic environments like coastal wetlands, which are inundated with seawater during storm surges or tidal events associated with sea-level rise. Yet, it is unknown how seawater salinity will impact Fe(II)-catalyzed ferrihydrite transformation or the fate of bound OC. We reacted ferrihydrite with Fe(II) aq under anoxic conditions in the absence and presence of dissolved organic matter (DOM). We compared treatments with no salts (DI water), NaCl-KCl salts, and artificial seawater mixes (containing Ca and Mg ions) with or without SO 4 2- /HCO 3 - . Both XRD and Mössbauer showed that NaCl-KCl favored lepidocrocite formation, whereas Ca 2+ /Mg 2+ /SO 4 2- /HCO 3 - ions in seawater overrode the effects of NaCl-KCl and facilitated goethite formation. We found that the highly unsaturated and phenolic compounds (HuPh) of DOM selectively bound to Fe minerals, promoting nanogoethite formation in seawater treatments. Regardless of salt presence, only 5-9% of Fe-bound OC was released during ferrihydrite transformation, enriching HuPh relative to aliphatics in solution. This study offers new insights into the occurrence of (nano)goethite and the role of Fe minerals in OC protection in coastal wetlands.

Constructing a C-N bond by merging electrochemistry and nickel catalysis is considered a powerful strategy. Herein, we investigate highly efficient intramolecular amination at room temperature with excellent functional group tolerance. Mechanistic studies suggest that the rapid ligand exchange may lead to the Ni I /Ni III catalytic cycle. This method not only provides a new perspective for intramolecular amination but also offers a novel approach for constructing the benzothiazine scaffold.

As the exploration and development of deep wells have emerged as a key option to extract more oil and gas resources trapped underneath, high-temperature formations impose stringent requirements on the thermal stability of plugging agents used in water-based drilling fluids. In this work, β-cyclodextrin, with its unique conical toroidal rigid stable structure and internal hydrophobic and external hydrophilic special adsorption capacity, was first grafted with maleic anhydride to prepare a silicone polymer and then copolymerized with dimethyldiallylammonium chloride (DMDAAC) in the presence of coupling agent vinyltriethoxysilane (A151) and cross-linking divinylbenzene (DVD) to finally obtain a high-temperature resistant plugging agent (AMMD). Subsequently, the molecular structure was evidenced and the performance of AMMD was examined in the polysulfonate-base fluid via a series of tests including high-temperature high-pressure filtration loss, sand tray plugging, and drilling fluid displacement, and the results were compared with the counterpart Soltex under the same conditions. The optimal synthesis conditions for the plugging agent were found as total monomer concentration of 25%, initiator mass fraction of 1% (based on the mass of monomers), monomer feed ratio of m (DVD):m(A151):m(DMDAAC):m(MD) of 15:3:2:15, pH value of 10, reaction temperature of 75 °C, and reaction time of 4 h. FT-IR spectra indicated that the monomers used to prepare AMMD were successfully involved in the reaction for the design of the plugging agent structure. TGA showed that AMMD has a total weight loss of about 35.98% in the range of 284 to 453 °C. Moreover, the addition of 3%AMMD into the base fluid produced a 4.38-fold and 3.8-fold filtration loss control over 60 min at 200 °C using 400 and 800 mD sand trays, respectively, which were comparatively higher than the commercially available Soltex (ca. 3.72-fold and 3.14-fold, respectively, using 400 and 800 mD). This then contributed to AMMD's superior plugging performance in drilling fluid based on the drilling fluid displacement experiment, implying that AMMD could find potential use as a plugging agent in polysulfonate drilling fluid under severe geothermal conditions., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Atomically dispersed transition metal sites on nitrogen-doped carbon catalysts hold great potential for the electrochemical CO 2 reduction reaction (CO 2 RR) to CO due to their encouraging selectivity. However, their intrinsic activity is restricted by the hurdle of the high energy barrier of either *COOH formation or *CO desorption due to the scaling relationship. Herein, we discover a p-block aluminum single-atom catalyst (Al-NC) featuring an Al-N 4 site that enables disentangling this hurdle, which endows a moderate reaction kinetic barrier for *COOH formation and *CO desorption, as validated by in situ attenuated total reflection infrared spectroscopy and theoretical simulations. As a result, the developed Al-NC shows a CO Faradaic efficiency (FE CO ) of up to 98.76% at -0.65 V vs RHE and an intrinsic catalytic turnover frequency of 3.60 s -1 at -0.99 V vs RHE, exceeding those of the state-of-the-art Ni-NC and Fe-NC counterparts. Moreover, it also delivers a partial CO current of 309 mA·cm -2 at 93.65% FE CO and 605 mA at >85% FE CO in a flow cell and membrane electrode assembly (MEA), respectively. Strikingly, when using low-concentration CO 2 (30%) as the feedstock, this catalyst can still deliver a partial CO current of 240 mA at >80% FE CO in the MEA. Considering the earth-abundant character of the Al element and the high intrinsic activity of the Al-NC catalyst, it is a promising alternative to today's transition metal-based single-atom catalysts.

Deoxynivalenol (DON) can induce endoplasmic reticulum (ER) stress, mitochondrial ROS burst, and macrophage polarization. Here, we investigated the mechanism linking the above three aspects with the dose range relevant to low-level exposure in children. At 0.5 μg/kg bw/day, we found remarkable liver and gut inflammatory responses after 6-week exposure in mice age comparable to humans 7-12 years old. Through antioxidant intervention, we found that ROS played a driver role in macrophage polarization and inflammatory responses induced by DON in the liver and gut. Further bioinformatics analysis uncovered that ER stress-associated protein MAPK7 (ERK5) may bind with AhR to initiate a mitochondrial ROS burst and macrophage M1 polarization. The downstream cellular events of MAPK7-AhR interaction may be mediated by the AhR/STAT3/p-STAT(Ser727) pathway. This mechanism was further supported by DON toxicity mitigation using cyanidin-3-glucoside (C-3-G), which docks to MAPK7 oligomerization region 200-400 aa and disrupts MAPK7-AhR interaction. Overall, our study provides novel evidence and mechanism for DON-induced inflammatory responses in the liver and gut system. Our findings call attention to the health risks associated with low-level DON exposure in the prepuberty children population.

The sustainable construction of spirocyclic compounds is important to the scientific community and the pharmaceutical industries. Herein, we demonstrate a carbamoyl radical-initiated intramolecular dearomative spirocyclization to access the spiro-cyclohexadiene oxindoles under visible light irradiation, which constitutes the first example of accessing the I-substituted derivatives that facilitate diversified transformations. Additionally, the scalability, late-stage modification of drugs, and significant antitumor activity of the products demonstrate the novel spirocyclic synthesis platform for expediting drug development.

Banana anthracnose, caused by Colletotrichum fructicola , significantly reduced the postharvest fruit quality. Employing biocontrol strategies offers a sustainable approach to enhance agricultural practices. The Burkholderia sp . strain BX1 hinders the growth and appressorium formation of C. fructicola , and its sterile filtrate lowers the anthracnose incidence while preserving the fruit quality. Scanning electron microscopy and genomic analyses confirmed BX1 as Burkholderia pyrrocinia . AntiSMASH analysis identified three siderophores with high similarity, and improved MALDI-TOF IMS confirmed the presence of the siderophore pyochelin. Furthermore, the BX1 filtrate suppressed the expression of virulence genes in C. fructicola and induced the expression of disease resistance genes in banana. However, the presence of 80 μM iron ions notably mitigated BX1's inhibitory effects and reversed the changes in related gene expression. These results underscore BX1's robust efficacy as a biocontrol agent in managing banana anthracnose, highlight the effective antifungal compounds, and elucidate the influence of environmental factors on biocontrol effectiveness.

Anisotropic domains with 180° periodicity are known to be universally present on graphene as well as on other two-dimensional (2D) crystals. The physical origin of the domains and the mechanism of its anisotropy are, however, still unclear. Here, by employing in-plane elastic imaging by torsional resonance atomic force microscopy (TR-AFM), we demonstrate that the observed domains on graphene are of in-plane elastic (shear) anisotropy but not of friction anisotropy as commonly believed. Our results also support that the anisotropic domains originate from self-assembled environmental adsorbates on graphene surfaces. The more densely packed backbone of the highly ordered molecules within a domain defines the major axis of the shear anisotropy of the latter. This work suggests a quantitative understanding of the characteristics of anisotropic domains on 2D materials. It also demonstrates TR-AFM as a powerful tool to study the in-plane elastic anisotropy of materials, including organic molecular crystals.

We describe an allylation reaction between 2-(2-azaaryl)acetic acids and allylic electrophiles catalyzed synergistically by a dual system consisting of borinic acid and a Pd complex under mild conditions. The decarboxylative allylation proceeds via a boron-bound enamine intermediate, which then interacts with a π-allylpalladium intermediate from the allylic electrophile. High yields of diallylation products highlight the method's efficiency. Intriguingly, when using 2-(2-pyridyl)acetic acid with a C3 substituent on the pyridyl ring, the reaction exclusively yields monoallylation products.

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.

This study aimed to explore the effects of S-nitrosylation on caspase-3 modification and its subsequent effects on beef myofibril degradation in vitro. Recombinant caspase-3 was reacted with different concentrations of S-nitrosoglutathione (GSNO, nitric oxide donor) at 37 °C for 30 min and subsequently incubated with purified myofibrillar protein from bovine semimembranosus muscle. Results indicated that the activity of caspase-3 was significantly reduced after GSNO treatments ( P < 0.05) and showed a dose-dependent inhibitory effect, which was attributed to the increased S-nitrosylation extent of caspase-3. LC-MS/MS analysis revealed that caspase-3 was S-nitrosylated at cysteine sites 116, 170, 184, 220, and 264. Moreover, the degradation of desmin and troponin-T was notably suppressed by S-nitrosylated caspase-3 ( P < 0.05). To conclude, protein S-nitrosylation could modify the cysteine residues of caspase-3, which accounts for the reduced caspase-3 activity and further represses its proteolytic ability on beef myofibrillar protein.

The active site is a highly anticipated property of adsorbent in the field of separation, as it enables a concurrent enhancement of both adsorption efficiency and adsorption rate. Herein, employing morphology-oriented regulation, we successfully fabricated heterogeneous MgO adsorbent from a magnesium-based metal-organic framework (MOF) precursor, octahedral MgO-M and laminated sheets MgO-P, for the capture of Congo red (CR). Specifically, the octahedron MgO-M exhibits a greater abundant of moderately and strongly alkaline sites, which facilitate the adsorption of CR. Furthermore, the synergistic effect between alkaline site and lattice oxygen further enhances the adsorption process. The adsorption data align more closely with the Pseudo-second-order kinetic model and Langmuir models. Notably, the exceptional adsorption capacity (exceeding 1900 mg·g -1 for MgO-M) and the secondary regeneration efficiency (over 96% removal rate across six cycles) offer promising prospects for future industrial applications, effectively addressing challenges related to poor water stability and difficult storability. Additionally, characterizations reveal the positive roles of alkaline sites, lattice oxygen, and pore structure in capturing significant quantities of CR through mechanisms such as electrostatic interactions, hydrogen bonding, and pore filling., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Bacterial RNA polymerase (RNAP), the core enzyme responsible for bacterial transcription, requires the NusG factor for efficient transcription elongation and termination. As the primary binding site for NusG, the RNAP clamp-helix (CH) domain represents a potential protein-protein interaction (PPI) target for novel antimicrobial agent design and discovery. In this study, we designed a pharmacophore model based on the essential amino acids of the CH for binding to NusG, such as R270, R278, and R281 ( Escherichia coli numbering), and identified a hit compound with mild antimicrobial activity. Subsequent rational design and synthesis of this hit compound led to improved antimicrobial activity against Streptococcus pneumoniae , with the minimum inhibitory concentration (MIC) reduced from 128 to 1 μg/mL. Additional characterization of the antimicrobial activity, inhibitory activity against RNAP-NusG interaction, and cell-based transcription and fluorescent assays of the optimized compounds demonstrated their potential for further lead optimization.

The antibacterial mechanism of condensed tannins (CTs) obtained from tea has been elucidated, but the mechanism of legume-derived CTs remains unclear. The mechanisms of legume- and tea-derived CTs probably differ due to the diverse compositions of CTs. Previous research found that sainfoin CTs directly inhibited the growth of Pediococcus . The present study investigated the inhibition mechanism of CTs against Pediococcus pentosaceus SF11 (SF11) through proteomic analysis. The results showed that the minimum inhibitory concentration (MIC) of CTs against SF11 was 1500 mg/L and that CTs increased cell membrane permeability in a dose-dependent manner. In total, 418 differentially expressed proteins (DEPs) were identified between the CT treatment and the control, among which 341 were down-regulated and 77 were up-regulated in the CT treatment. The protein interaction network showed that the expression of only two DEPs was highly different between CT treated and control (|log2FC|> 2); the atp D protein was up-regulated in the CT-treated group, which was involved in ATP synthesis; down-regulated DEPs were most involved in lipoteichoic acid synthesis, peptidoglycan synthesis, and glycine metabolism. Twenty-seven proteins were not detected after CT treatment, which were involved in functions including fatty acid synthesis, RNA synthesis and translation, drug resistance, and cell membrane permeability in SF11. Therefore, the findings suggest that the inhibition mechanism of CTs may be related to cell membrane damage and inhibition of cell reproduction., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Small molecule dyes remain essential biological tools, yet only a handful of environmentally responsive fluorogenic small molecules are available for routine characterization of protein state. Here, we report the development and execution of a high throughput screen to identify compounds that increase in fluorescence in response to binding of lipophilic sites of proteins. This effort yielded two small molecules that potently indicate the presence of a range of common proteins and outperform common dyes in differential scanning fluorimetry experiments. Structure activity relationship studies revealed that these two scaffolds can be tuned both for their quantum yields and emission wavelengths. This work affords a straightforward framework for the discovery of new fluorophores and adds two fluorogenic probes to the toolbox for studying protein state.

5-Aminovalerate (5-AVA), 5-hydroxyvalerate (5-HV), and 1,5-pentanediol (1,5-PDO) are l-lysine derivatives with extensive applications in the production of materials such as polyesters, polyurethane, plasticizers, inks, and coatings. However, their large-scale production is limited by the lack of efficient synthetic pathways. Here, we aimed to construct multiple synthetic pathways by screening the key enzymes involved in the synthesis of these compounds in Escherichia coli . The engineered pathway utilizing RaiP demonstrated a superior catalytic efficiency. The LER strain that overexpressed only raiP successfully synthesized 9.70 g/L 5-HV and 8.31 g/L 5-AVA, whereas the strain LERGY that overexpressed raiP , gabT, and yahK accumulated 9.72 g/L 5-HV and 7.95 g/L 5-AVA from 20 g/L glucose. The introduction of exogenous transaminases and dehydrogenases enhanced cell growth and fermentation efficiency with respect to 5-HV synthesis, albeit without significantly impacting the yield. Strain LE05, incorporating only two exogenous enzymes, RaiP and CaR, produced 1.87 g/L 1,5-PDO, 3.85 g/L 5-HV, and 4.78 g/L 5-hydroxyglutaraldehyde from 20 g/L glucose after 6 days. The strain LE02G, fortified with transaminase, dehydrogenase, and NADPH regeneration system, accumulated 7.82 g/L 1,5-PDO, whereas the aldp -knock out LE02G2 synthesized 10.98 g/L 1,5-PDO from 50 g/L glucose in fed-batch fermentation after 6 days, yielding 0.22 g/g glucose (0.37 mol/mol). Introducing the NADPH regeneration pathway and deleting the NADPH-consuming pathways increased the 1,5-PDO yield and decreased the precursor concentration. The proposed pathways and engineering strategies presented in this study can prove instrumental in developing biological routes for the practical production of 5-AVA, 5-HV, and 1,5-PDO.

The combination of the photothermal effect and immunoassay serves as a potent tool for crafting cost-effective and user-friendly biosensing systems. To ensure efficient light-to-heat conversion, we integrated three-dimensional-printed (3D printed) technology to devise a novel design. This design functions as the structural support for both the cell phone and laser probe, as well as a means for sample handling. The main body features a three-way cavity structure, securing the test sample at a fixed position to maintain consistent light distance and angle, thereby minimizing testing errors. Card slot insert facilitates precise sample positioning to ensure the adequacy of receiving light. The sample holder's wide front and narrow back design enables the accommodation of fixed samples while providing a broad field of view, with intervals therein effectively preventing cascading heat. Our design employs MB@MOF235 (methylene blue adsorbed by iron terephthalate) as the photothermal reagent, successfully enabling the detection of α-fetoprotein (AFP). The detection range spans from 0.01 to 50 ng/mL, with a lower detection limit (LOD) of 0.032 pg/mL. The detection method, combining simplicity, portability, and visualization, offers a reliable reference for furthering precision medicine toward personalized medicine. Meanwhile, to verify the method's accuracy electrochemical testing was conducted to support the proof using the electro-oxidizing activity of MB.

Drug-induced liver injury (DILI) stands as a significant concern in drug safety, representing the primary cause of acute liver failure. Identifying the scientific literature related to DILI is crucial for monitoring, investigating, and conducting meta-analyses of drug safety issues. Given the intricate and often obscure nature of drug interactions, simple keyword searching can be insufficient for the exhaustive retrieval of the DILI-relevant literature. Manual curation of DILI-related publications demands pharmaceutical expertise and is susceptible to errors, severely limiting throughput. Despite numerous efforts utilizing cutting-edge natural language processing and deep learning techniques to automatically identify the DILI-related literature, their performance remains suboptimal for real-world applications in clinical research and regulatory contexts. In the past year, large language models (LLMs) such as ChatGPT and its open-source counterpart LLaMA have achieved groundbreaking progress in natural language understanding and question answering, paving the way for the automated, high-throughput identification of the DILI-related literature and subsequent analysis. Leveraging a large-scale public dataset comprising 14 203 training publications from the CAMDA 2022 literature AI challenge, we have developed what we believe to be the first LLM specialized in DILI analysis based on LLaMA-2. In comparison with other smaller language models such as BERT, GPT, and their variants, LLaMA-2 exhibits an enhanced out-of-fold accuracy of 97.19% and area under the ROC curve of 0.9947 using 3-fold cross-validation on the training set. Despite LLMs' initial design for dialogue systems, our study illustrates their successful adaptation into accurate classifiers for automated identification of the DILI-related literature from vast collections of documents. This work is a step toward unleashing the potential of LLMs in the context of regulatory science and facilitating the regulatory review process.

Six new angucycline structures, including spirocyclione A ( 1 ), which contains an unusual oxaspiro[5.5]undecane architecture, and its ring-A-cleaved product spirocyclione B ( 2 ), were discovered by heterologous expression of a type II polyketide biosynthetic gene cluster captured from a marine actinomycete strain Streptomyces sp. HDN155000. Three flavoprotein monooxygenases are confirmed to be responsible for the oxidative carbon skeleton rearrangements in the biosynthesis of compounds 1 and 2 . The obtained compounds showed promising cytotoxicity against different types of cancer cells.