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Increasing evidences suggest that the methyltransferase NSUN2 catalyzes 5-methylcytosine (m5C) modifications on viral RNAs, which are essential for the replication of various viruses. Despite the function of m5C deposition is well characterized, other potential roles of NSUN2 in regulating viral replication remain largely unknown. In this study, the m5C modified residues catalyzed by NSUN2 on enterovirus 71 (EV71) RNAs were mapped. NSUN2, along with m5C modifications, played multiple roles during the EV71 life cycle. Functional m5C modified nucleotides increased the translational efficiency and stability of EV71 RNAs. Additionally, NSUN2 was found to target the viral protein VP1 for binding and promote its stability by inhibiting the ubiquitination. Furthermore, both viral replication and pathogenicity in mice were largely attenuated when functional m5C residues were mutated. Taken together, this study characterizes distinct pathways mediated by NSUN2 in regulating EV71 replication, and highlights the importance of its catalyzed m5C modifications on EV71 RNAs for the viral replication and pathogenicity.

Although in vitroneuronal network models hold great potential for advancing neuroscience research, with the capacity to provide fundamental insights into mechanisms underlying neuronal functions, the dynamics of cell communication within such networks remain poorly understood. Here, we develop a customizable, polymer modified three-dimensional gold microelectrode array with sufficient stability for high signal-to-noise, long-term, neuronal recording of cultured networks. By using directed spatial and temporal patterns of electrical stimulation of cells to explore synaptic-based communication, we monitored cell network dynamics over 3 weeks, quantifying communication capability using correlation heatmaps and mutual information networks. Analysis of synaptic delay and signal speed between cells enabled us to establish a communication connectivity model. We anticipate that our discoveries of the dynamic changes in communication across the neuronal network will provide a valuable tool for future studies in understanding health and disease as well as in developing effective platforms for evaluating therapies.

Hydrogen sulfide (H2S) is an important endogenous gas transmitter that plays a critical role in various physiological and pathological processes and can also cause a negative impact on foodstuffs. In this study, we designed and synthesized a simple, easily available, high-yield, and low-cost near-infrared (λem= 710 nm) fluorescent probe, DEM-H2S, with a substantial Stokes shift (205 nm) for the detection of H2S. DEM-H2Sfeatures high selectivity and sensitivity (LOD = 80 nM) toward H2S, accompanied by a noticeable color change. Upon interaction with H2S, DEM-H2Sexhibits a restored ICT (Intramolecular Charge Transfer) process, thereby manifesting near-infrared fluorescence. DEM-H2Shas been successfully utilized to detect H2S in actual water samples and to monitor the spoilage of food items, such as pork, shrimp, and eggs. Furthermore, DEM-H2Senables the imaging of endogenous and exogenous H2S in living MCF-7 cells and zebrafish. Hence, DEM-H2Sprovides an attractive method for the detection of H2S in environmental, food, and biological systems, holding potential value in physiological and pathological research.

The effects of extrusion ratio (ER) on the microstructures, static mechanical properties, and tension-compression high cycle fatigue (HCF) behavior of the as-extruded Mg–5Zn–1Mn (ZM51) alloy was investigated systematically, and the HCF mechanism was discussed. The results show that texture weakening and grain refinement caused by increasing the ER can effectively enhance the static mechanical properties and alleviate the tensile-compressive asymmetry of the alloy. The fatigue strength at 107cycles is 124 ± 5, 138 ± 4, and 142 ± 5 MPa for ER8, ER11.5, and ER23, respectively, and the corresponding fatigue ratio is approximately 0.45, 0.49, and 0.50, which means that the as-extruded ZM51 alloy possesses outstanding fatigue resistance. The failure analysis and microstructure evolution of post-fatigued samples demonstrated that the stress amplitudes and microstructure characteristics strongly influence the HCF mechanism of the alloy. At high-stress load, close to the tensile yield strength 160–180 MPa, abundant {101‾2} residual twin bands were observed near the fracture surface. Twinning/detwinning deformation is the dominant fatigue mechanism due to the plastic deformation incompatibility between the matrix and the residual twins. At low-stress load, close to the fatigue strength 125–145 MPa, the fatigue crack initiation mechanism transits from twinning/detwinning to dislocation slip. Grain refinement and texture weakening inhibit the activation of {101‾2} twins, alleviate the twin-dislocation interaction, and promote dislocation slip to dominate the fatigue deformation, thereby enhancing the fatigue life of the alloy. This work provides new insight into the design and development for enhancing the fatigue resistance of wrought Mg alloy to ensure the long-term service safety of structural materials.

Methicillin-resistant Staphylococcus aureus(MRSA) exhibits multiresistance to a plethora of antibiotics, therefore, accurate detection methods must be employed for timely identification to facilitate effective infection control measures. Herein, we construct a high-efficiency ratiometric electrochemiluminescent (ECL) biosensor that integrates multiple exonuclease (Exo) III-assisted cyclic amplification units for rapid detection of trace amounts of MRSA. The target bacteria selectively bind to the aptamer, triggering the release of two single-stranded DNAs. One released DNA strand initiates the opening of a hairpin probe, inducing exonuclease cleavage to generate a single strand that can form a T-shaped structure with the double strand connecting the oxidation–reduction (O–R) emitter of N-(4-aminobutyl)-N-ethylisoluminol gold (ABEI-Au). Consequently, ABEI-Au is released upon Exo III cleavage. The other strand unwinds the hairpin DNA structure on the surface of the reduction–oxidation (R–O) emitter ZIF-8@CdS, facilitating the subsequent release of a specific single strand through Exo III cleavage. This process effectively anchors the cathode-emitting material to the electrode. The Fe(III) metal-organogel (Fe-MOG) is selected as a substrate, in which the catalytic reduction of hydrogen peroxide by Fe(III) active centers accelerates the generation of reactive oxygen species and enhances signals from both ABEI-Au and ZIF-8@CdS. In this way, the two emitters cooperate to achieve bacterial detection at the single-cell level, and a good linear range is obtained in the range of 100–107CFU/mL. Moreover, the sensor exhibited excellent performance in detecting MRSA across various authentic samples and accurately quantifying MRSA levels in serum samples, demonstrating its immense potential in addressing clinical bacterial detection challenges.

In recent years, the issue of sepsis control has become increasingly significant in the healthcare field. As a result of blood poisoning by pathogens, sepsis infects every organ and tissue in the body, leading to organ failure and death. The need for effective treatment remains not fulfilled, and novel approaches are desperately needed. In this research investigation, we have designed and developed the ciprofloxacin-loaded zeolitic imidazolate framework (CI@ZIF-90) for pH-responsive drug delivery application in sepsis treatment. The physicochemical characteristics of CI@ZIF-90 nanocomposite was examined by prominent analytical techniques. The in vitro drug release analysis indicated CI@ZIF-90 achieved 98% of release after 72 h at pH 5.0. The anti-microbial analyses by well-diffusion, MIC and bio-film assays provide evidences that CI@ZIF-90 have enhanced inhibition action against sepsis-causing pathogens. The suitability of the CI@ZIF-90 has been proved by MTT and cell proliferation assays on L929 fibroblast cells. Subsequently, in vivo suitability was observed by Artemia salinalethality assay. The novelty of the present study involves pH-responsive ZIF-90 nanoformulation increased drug delivery efficiency, biocompatibility and efficient anti-microbial action with a new combination of CI drug molecules. Overall research work highlights, CI@ZIF-90 could be a potential stimuli-responsive drug delivery system for neonatal sepsis therapy.

To improve the quality of products obtained by interferometric phase signal time-series analysis of synthetic aperture radar (TS-InSAR) techniques, various phase reconstruction approaches have been developed recently. The commonly used methods assume that synthetic aperture radar (SAR) observations are complex circular Gaussian (CCG) distributed, making them vulnerable to outliers. Noting this, a robust probabilistic generative SAR (RPGSAR) interferometric phase reconstruction method, named RPGSAR, is proposed in this article. The RPGSAR introduces a multivariate complex t-distribution (MCT) to a probabilistic generative model, which establishes a projection matrix depicting statistical behaviors of reconstructed phase. Furthermore, to resolve this model, a targeted expectation maximization (EM) algorithm is deduced and implemented. It is worth noting that the degree of freedom (DOF) can be automatically estimated by the RPGSAR. To validate the RPGSAR, we first apply the phase linking (PL) and principal components analysis (PCA) methods to simulated data. The experimental results demonstrated the RPGSAR’s ability to handle outliers. Furthermore, real Sentinel-1A SAR stacks consisting of different number of images are reconstructed by these methods. The results show that the proposed method can provide more consistent interferometric phases in all stack size cases compared with the PL and PCA methods, thus further confirming its effectiveness.

In this work, we have developed a novel fiber sensor based on optical path multiplexing (OPM) for measuring ultralow chemical oxygen demand (COD) concentration. The cumulative effect brought by the novel OPM structure could amplify sensor’s sensitivity, which significantly improves the detectability in ultraviolet-visible (UV–Vis) spectrometry method. Meanwhile, structural optimization method based on maximum coupling efficiency have been demonstrated. In the UV–Vis absorption spectroscopy experiment, the absorbance of 215 nm wavelength and the area under the absorption spectrum were used to estimate the COD concentration, respectively. The results shown that they all increased linearly with the change of COD concentration, and kept the strictly linear relationship in the ranges of 0–6 mg/L. Their linear correlation coefficients are above 0.9977. Surprisingly, the COD measurement curve represented by the area under absorption spectrum gave a better performance in this study, whose RMSE, LOD, and LOQ were superior to 0.0165, 0.0362, and 0.1207 mg/L, respectively. The good performance indicators revealed accurate measuring ability of the OPM-based fiber sensor for ultralow COD levels. More importantly, the open architecture in OPM-based fiber sensor has shown a good application prospect for in situ water quality assessment.

An efficient fluorinated alcohol-driven cascade [1,5]-hydride transfer/cyclization between o-amino pyridyl aldehydes and primary amines has been developed. This unique transformation enabled an array of tetrahydropyridino[2,3-d]pyrimidine construction. Furthermore, the encouraging antifungal activity of Thanatephorus cucumeriswas demonstrated by this tetrahydropyridino[2,3-d]pyrimidine core structure.

Batch experiments were conducted to remove fluoride from simulated flue-gas scrubbing wastewater using La(NO3)3·6H2O. The effects of SO42−concentration and addition sequence on residual fluoride concentration and precipitates properties (mass, morphology, phase structure and composition) were investigated using fluorine ion-selective electrode, SEM, EDS and XRD. The results show that precipitates obtained in the presence of SO42−mainly consisted of LaF3in irregular bulk shape with high crystallinity. However, amorphous particles were observed in the precipitates, which were speculated to be La[SO4]F. Due to the smaller stoichiometric coefficient of F/La in La[SO4]F compared to that in LaF3, the residual fluoride concentration increased as the SO42−concentration ascended. Subsequent addition of SO42−after lanthanum salt could inhibit the formation of amorphous particles, and further reduce the residual fluoride concentration. At a La/F molar ratio of 1:3.0, the subsequent addition of SO42−(0.02 mol/L) after La(NO3)3∙6H2O could obtain a residual fluoride concentration of 6.9 mg/L, lower than the required fluoride emission level. Further increasing the La/F molar ratio could reduce residual fluoride concentration to below 2 mg/L, while the risk of retaining La3+would emerge.

We propose a simple interface engineering method to modify the interface between perovskite and ETL by using multifunctional carbon dots (CDs). Interactions between CDs and perovskite layers suppress interfacial recombination and improve device performance; and inhibit photo-induced I2release and organic cation volatilization causing irreversible degradation of perovskite films, thereby enhancing long-term operational stability of PSCs.

Acetaldehyde (CH3CHO) is known as a primary carcinogen, and the development of wearable gas sensors for its detection at room temperature has rarely been rarely reported. Herein, MoS2quantum dots (MoS2QDs) have been employed to dope with poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT: PSS) via a simple in situ polymerization technique, and the CH3CHO gas-sensing properties of the resultant flexible and transparent film were investigated. MoS2QDs had been evenly dispersed into the polymer, and it was shown that PEDOT: PSS doped with the 20 wt % MoS2QDs sensor exhibited the highest response value of 78.8% against 100 ppm CH3CHO and its detection limit reached 1 ppm. Moreover, the sensor response remained stable for more than 3 months. In particular, the different bending angles (from 60 to 240°) had little effect on the sensor response to CH3CHO. The possible reason for the enhanced sensing properties was attributed to the large number of reaction sites on the MoS2QDs and the direct charge transfer between the MoS2QDs and PEDOT: PSS. This work suggested a platform to inspire MoS2QDs-doping PEDOT: PSS materials as wearable gas sensors for highly sensitive chemoresistive sensors to detect CH3CHO at room temperature.

Free radicals and their induced oxidative damage in living organisms are related to many diseases. Natural substances with antioxidant capacity are effective in scavenging free radicals, which could slow down aging and prevent diseases. However, the existing methods for the evaluation of antioxidant activity mostly required the use of complex instruments and operations. In this work, we proposed a unique method to determine the total antioxidant capacity (TAC) in real samples through a photosensitization-mediated oxidation system. N- and P-doped long-lived phosphorescent carbon dots (NPCDs) were developed, which exhibited the effective intersystem crossing from the singlet to the triplet state under UV light irradiation. Mechanism study confirmed that the energy of excited triplet state in NPCDs generated superoxide radicals and singlet oxygen through type I and type II photoreactions, respectively. On this basis, the quantitative determination of TAC in fresh fruits was achieved using 3,3′,5,5′-tetramethylbenzidine (TMB) as a chromogenic bridge in the photosensitization-mediated oxidation system. This demonstration will not only provide a facile way to analyze antioxidant capacity in practical samples but also broaden the applications of phosphorescent carbon dots.

Herein, we disclose a Rh(III)-catalyzed C–H activation/annulation reaction for the derivatization of Lys-based peptides, in situaffording diverse peptide-isoquinolone conjugates. This approach features racemization-free conditions, high atom- and step-economy, excellent chemo- and site-selectivity, and broad scope including substrates bearing unprotected Trp and Tyr, free Ser and Gln, and Met residues. The peptide-isoquinolone conjugates also display good fluorescent properties with maximum emission wavelengths up to 460 nm. Importantly, preliminary antifungal activity studies indicate that peptide–isoquinolone conjugates show potential activities toward crop and forest pathogenic fungi, in which the peptide–isoquinolone conjugate bearing unprotected Tyr residue exhibits much better antifungal activities toward B. cinerea Pers. and C. chrysospermathan the positive control.

Chemical nerve agents are highly toxic organophosphorus compounds that are easy to obtain and can be utilized by terrorists to threaten homeland security and human safety. Those organophosphorus nerve agents contain nucleophilic ability that can react with acetylcholinesterase leading to muscular paralysis and human death. Therefore, there is great importance to explore a reliable and simple method to detect chemical nerve agents. Herein, the o-phenylenediamine-linked dansyl chloride as a colorimetric and fluorescent probe has been prepared to detect specific chemical nerve agent stimulants in the solution and vapor phase. The o-phenylenediamine unit serves as a detection site that can react with diethyl chlorophosphate (DCP) in a rapid response within 2 min. A satisfied relationship line was obtained between fluorescent intensity and the concentration of DCP in the range of 0–90 μM. In the optimized conditions, we conducted the fluorescent titration to measure the limits of detection (0.082 μM) with the fluorescent enhancement up to 18-fold. Fluorescence titration and NMR studies were also conducted to explore the detection mechanism, indicating that the formation of phosphate ester causes the intensity of fluorescent change during the PET process. Finally, probe 1coated with the paper test is utilized to detect DCP vapor and solution by the naked eye. We expect that this probe may give some admiration to design the small molecule organic probe and applied in the selectivity detection of chemical nerve agents.

Magnesium cylindrical parts have relatively poor mechanical properties and distinct anisotropy of microstructure, which hinder their application as structural components. To improve the performance of WE71 cylindrical parts, multi-direction forging (MDF) was introduced before back extrusion, and the microstructure and mechanical properties were investigated. Results of microstructure show that the grain size in the outer of the cylindrical bottom is refined from 30.1 to 27.7 μm, the microstructure is more uniform and the dislocation density is higher. The bimodal grain structure is formed in the outer of the cylindrical wall, which is ascribed to the formation of Mg5RE phases along grain boundaries. These phases result in the Zener pinning effect on grain boundaries and the reduction of DRX volume fraction. The texture type of the cylindrical bottom is <0001>∥EDand the cylindrical wall is <101¯0>∥ED, and the maximum pole intensity is 1.986 and 1.664, respectively. Results of the tensile test at room temperature show that combined improved strength and ductility of the cylindrical part is attained after introducing the MDF process. The ultimate tensile strength (UTS), yield strength (YS) and elongation are 279 MPa, 185 MPa and 12% at the bottom and 299 MPa, 212 MPa and 20% at the wall.

Grain size is a key factor influencing grain yield and appearance quality in rice. We identified twelve quantitative trait loci (QTL) for grain length (GL), nine for grain width (GW), and nine for 1000-kernel weight (TKW) using GLU-SSSLs, which are single-segment substitution lines with Oryza glumaepatulaas donor parent and Huajingxian 74 (HJX74) as recipient parent. Among the QTL, qGL1-2, qGL1-4, qGL9-2, qGW2-2, qGW9-1and qTKW9-2contributed to high grain yield. GL9was identified as a candidate gene for qGL9-2by map-based cloning and sequencing, and is a novel allele of GS9. The kernel of NIL-gl9was slenderer and longer than that of HJX74, and the TKW and grain yield per plant of NIL-gl9were higher than those of HJX74. The proportion of grain chalkiness of NIL-gl9was much lower than that of HJX74. Thus, gl9increased grain yield and appearance quality simultaneously. Three pyramid lines, NIL-gs3/gl9, NIL-GW7/gl9and NIL-gw8/gl9, were developed and the kernel of each was longer than that of the corresponding recipient parent lines. The gl9allele may be beneficial for breeding rice varieties with high grain yield and good appearance quality.

With DSC, OM, XRD, SEM, TEM, Vickers hardness tester, and universal testing machine, the evolution of the microstructure and mechanical properties of Mg−6Zn−3Sn alloy during homogenization was studied, the reason for overburning and diffusion kinetics of the alloy were analyzed, and the homogenization scheme was determined. The results show that the decomposition of the Mg2Zn3phase, accompanied by the precipitation of the Mg2Sn phase, occurs after the single-stage homogenization. When the homogenization temperature increases to 350 °C, the Mg2Zn3phase leads to overburning. The suitable homogenization scheme for the alloy is (335 °C, 24 h) + (400 °C, 6 h). During the double-stage homogenization, the hardness of the alloy decreases continuously and the mechanical properties show an increase first and then decrease, which is related to the solid solution of Zn and Sn atoms and the precipitation of the Mg2Sn phase.

Currently, a widely accepted, objective, and repeatable procedure for determining the flaw parameters used in the glass failure prediction model does not exist. Historically flaw parameters were primarily based on statistical measures and the researchers’ interpretation of experimental data. This paper advances a procedure to calculate the flaw parameters used in the two-parameter form of the glass failure prediction model for holes based on the well-known maximum likelihood estimator method based on destructive testing. Additionally, the paper presents a three-parameter form of the glass failure prediction model for holes to incorporate the residual compressive surface stress for heat-treated glass into the load resistance. The paper also advances a procedure to calculate the flaw parameters for the three-parameter form of the glass failure prediction model based on the maximum likelihood estimator method. The work herein uses failure test data from a set of historical four-point bending tests of glass beams with a hole located at the geometric center to illustrate the procedure to determine flaw parameters. Because the flaw parameters for the three-parameter glass failure prediction model are a function of the residual compressive surface stress, a method is presented to choose the residual compressive surface stress value to base the other two parameters upon. An example design scenario provides insight into the variations between the two- and three-parameter glass failure prediction models and the effect the residual compressive surface stress has on the load resistance.

Methicillin-resistant Staphylococcus aureus(MRSA) has become one of the greatest threats to human health due to its strong drug resistance, wide distribution range, and high infection rate. Rapid identification of MRSA strains is very important for accurate diagnosis and early treatment of MRSA infections. Here, we introduced an Exo III-assisted nanomotor mower to build 3D hotspots for rapid detection of MRSA by surface-enhanced Raman scattering (SERS). As the bacteria bound to the aptamer, two trigger chains were released from the double-stranded structure, and the nano-mowers were activated by opening a hairpin probe on gold nanoparticles (AuNPs). With the continued cleavage of Exo III and cyclic release of the trigger chain, multiple hairpin DNAs on the AuNPs were cleaved to increase the motor power. The resulting nano-mower continued slicing protective DNA from larger AuNPs, exposing the AuNPs. Without the protection of DNA, Mg2+in the buffer induced spontaneous aggregation of the AuNPs, and a large number of hotspots were formed for SERS measurements. Under optimal conditions, MRSA can be detected within 40 min, and the concentration of MRSA showed a good linear relationship with the SERS intensity at 1342 cm–1, with a limit of detection as low as 1 CFU/mL and a wide linear range (100to 107CFU/mL). This strategy creates a rapid bacterial detection method that performs well on actual samples utilizing portable Raman spectroscopy instruments, with potential applications in food detection, water detection, clinical treatment, and diagnosis.

C31H28N2O4, monoclinic, P21(no. 4), a= 10.2166(2) Å, b= 11.5327(2) Å, c= 11.6484(2) Å, β= 109.637(2)°, V= 1292.65(5) Å3, Z= 2, Rgt(F) = 0.0502, wRref(F2) = 0.1312, T= 149.9(5) K.