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Purpose: This study aims to present a high-end lesson study (HELS) model to develop students' subject competency. Data were collected from a Beijing suburban key senior high school in China. How the subject competency framework (SCF) supports HELS and develops students' subject competency in practice are discussed in this study. Design/methodology/approach: This study provides a four-dimensional SCF developed by the chemistry education research team at Beijing Normal University. Basic procedures of the HELS model involve the project plan, students' pre-test, lesson design workshop, first-round teaching implementation and improvement, second-round teaching implementation and evaluation, students' post-test, and results discussion. Data were collected from each of the procedures, and analysis of the data is conducted in both qualitative and quantitative approaches. Findings: The results show that the SCF supports HELS implementation by (1) identifying key teaching objectives based on curriculum standard requirements and students' subject competency performance; (2) organizing teaching content based on the core knowledge to develop cognitive mode; (3) designing tasks and activities regarding understanding--applying--transferring and innovating categories and sub-categories of SCF; (4) establishing students' cognitive perspectives and reasoning paths to promote their subject competency by teacher-student interaction. Originality/value: The HELS model provides theory-based pedagogical guidance for conducting lesson studies. It presents the SCF and orientation. The SCF is used throughout the entire process of HELS, including the identification of teaching objectives, the selection and organization of teaching content, and the design and implementation of teaching activities. It reflects a systematic instructional design-implementation-discussion-improvement-evaluation process. The SCF-based HELS can be applied to different topics and disciplines.

The prompt introduction of single-molecule science into undergraduates' curricula is an urgent but challenging task. However, the research experiments are often too complicated and the instruments are too expensive to be widely transferred into a compulsory course of undergraduate students. Herein, we introduce a recently developed nanopore technique into an accessible laboratory course for students with the advantages of simple operation, high repeatability, and low cost. The nanopore course serves to help undergraduates in practice to understand single-molecule behaviors, think at a single molecule level, and gradually develop single-molecule solutions for scientific issues. The learning activities for undergraduate students include setup of the instrument, fabrication of a biological nanopore on an artificial lipid bilayer membrane, detection of individual oligonucleotides, and data analysis. An experiment example is single-molecule detection of the model DNA sample poly(dA)[subscript n] (n = 4, 5) using the aerolysin nanopore. As our developed nanopore sensing system is simple, portable, and easy to handle, the experiment course could be implemented and popularized in undergraduates' laboratory education. For the undergraduate students who have taken general chemistry and/or biochemistry courses, this hands-on experience of nanopore experiments would benefit them with a better understanding of the chemical world at a single-molecule level and further using single-molecule tools in various applications including DNA and/or protein sequencing.

This study proposed frameworks for designing inquiry approaches with multimedia in science e-textbooks through exploring the extent and features of inquiry approaches with science topics in a digital textbook. Results revealed that the experiential, evidence-based and predict-observe-explain approaches are designed in 70% of the science topics. Such design differs by subject (earth science, biology, or physics). Through analyzing concrete examples, frameworks are consolidated to demonstrate how these approaches involve resources such as dialogue cartoons, animations, or simulations to assist students' inquiry and understanding of science phenomena. This study has implications for science e-textbook design and inquiry-based teaching in primary schools.

Abstract The oxidation of phenolic compounds is one of the most important reactions prevalent in various biological processes, often explicitly coupled with proton transfers (PTs). Quantitative descriptions and molecular-level understanding of these proton-coupled electron transfer (PCET) reactions have been challenging. This work reports a direct observation of PCET in photodetachment (PD) photoelectron spectroscopy (PES) of hydrogen-bonded phenolic (ArOH) nitrate (NO3 −) complexes, in which a much slower rising edge provides a spectroscopic signature to evidence PCET. Electronic structure calculations unveil the PCET processes to be isomer-specific, occurred only in those with their HOMOs localized on ArOH, leading to charge-separated transient states ArOH•+ ·NO3 − triggered by ionizing phenols while simultaneously promoting PT from ArOH•+ to NO3 −. Importantly, this study showcases that gas-phase PD-PES is a generic means enabling to identify PCET reactions with explicit structural and binding information.

Four vanadyl pyrophosphate (VPO) catalysts were prepared via the sesquihydrate precursor route using direct microwave irradiation and reflux synthesis methods. The synthesis of the sesquihydrate precursor was carried out in 2 stages. The synthesized catalysts were denoted as VPOs-DD, VPOs-RR, VPOs-RD, and VPOs-DR; where VPOs represented VPO catalysts produced through sesquihydrate precursor, and D and R represented direct microwave irradiation and reflux synthesis methods, respectively. The direct microwave irradiation synthesis method was found to reduce the synthesis duration significantly for both stages of the precursor synthesis, from 48 to 4 h. An exclusive secondary configuration, akin to a needle-shaped form in chrysanthemums, is specifically noted in VPOs-DD could increase the specific surface area by 35.4% compared to the bulkier structure of VPOs catalyst produced via the conventional reflux synthesis method (VPOs-RR). Direct microwave irradiation could induce the removal of more than 4 times the total amount of oxygen atoms from the lattice of V4+ and V5+ phases, as compared to the conventional reflux method counterpart. This ultimately produced VPOs catalysts with greater catalytic performances and TON. In summary, employing direct microwave irradiation could generate VPOs catalysts with increased efficiency, improved activity and selectivity as compared to the conventional reflux method.

Abstract Chemotherapy-induced drug resistance remains a major cause of cancer recurrence and patient mortality. ATP binding cassette subfamily B member 1 (ABCB1) transporter overexpression in tumors contributes to resistance, yet current ABCB1 inhibitors have been unsuccessful in clinical trials. To address this challenge, we propose a new strategy using tryptophan as a lead molecule for developing ABCB1 inhibitors. Our idea stems from our studies on bat cells, as bats have low cancer incidences and high ABCB1 expression. We hypothesized that potential ABCB1 substrates in bats could act as competitive inhibitors in humans. By molecular simulations of ABCB1-substrate interactions, we generated a benzylated Cyclo-tryptophan (C3N-Dbn-Trp2) that inhibits ABCB1 activity with efficacy comparable to or better than the classical inhibitor, verapamil. C3N-Dbn-Trp2 restored chemotherapy sensitivity in drug-resistant human cancer cells with no adverse effect on cell proliferation. Our unique approach presents a promising lead toward developing effective ABCB1 inhibitors to treat drug-resistant cancers.

Mineral dust particles are nonspherical and inhomogeneous; however, they are often simplified as homogeneous spherical particles for retrieving the refractive indices from laboratory measurements of scattering and absorption coefficients. The retrieved refractive indices are then employed for computing the optical properties of spherical or nonspherical dust model particles with downstream applications. This study aims to theoretically investigate uncertainties involved in the aforementioned rationale based on numerical simulations and focuses on a wavelength range of 355–1064 nm. Initially, the optical properties of nonspherical and inhomogeneous dust aerosols are computed as baseline cases. Subsequently, the scattering and absorption coefficients of homogeneous spheres and super-spheroids are computed at various refractive indices and compared with those of inhomogeneous dust aerosols to determine the dust refractive index. To mimic the real laboratory measurement, the size distribution of the baseline case is assumed to be unknown and determined through a process akin to using optical particle counters for sizing. The resulting size distribution differs from the original one of the baseline cases. The impact of discrepancies in size distributions on retrieving the dust refractive index is also investigated. Our findings reveal that these discrepancies affect scattering and absorption coefficients, presenting challenges in accurately determining the refractive index, particularly for the real parts. Additionally, the retrieved refractive indices are noted to vary with particle size primarily due to differences in size distribution, with imaginary parts decreasing as the particle size increases. A comparison between sphere models and super-spheroid models shows that the former tend to underestimate the imaginary parts, leading to an overestimation of single-scattering albedo. This study underscores the importance of employing consistent nonspherical models for both refractive index retrieval and subsequent optical simulation in downstream applications. Nevertheless, the impact of refractive index uncertainties on the asymmetry factor and phase matrix is found to be minimal, with particle shape playing a more significant role than differences in the imaginary parts of the dust refractive index.

This study introduces a novel approach for analyzing thin film interference spectra by employing a micro-spectrometer equipped with a spectral chip. Focusing on zinc oxide (ZnO) thin films prepared via the sol–gel method, this research aims to explore the films’ physical properties through spectral analysis. After obtaining the interference spectrum of the ZnO thin films, the peak positions within the spectrum were cataloged. Mathematical simulation was used to adjust the refractive index and thickness of the films to match the simulated interference peak positions with the observed peak positions. The thickness of the prepared ZnO film was estimated to be 4.9 μm and its refractive index at 80 °C was estimated to be 1.96. In addition, the measurement system was used to detect environmental changes, including temperature changes and gas exposure. It was observed that the optical characteristics of ZnO films exhibit marked variations with temperature shifts, enabling the establishment of a temperature calibration curve based on spectral feature displacement. In addition, experiments using a variety of gases showed that NO2 and gaseous isopropanol significantly affect the interference spectrum of ZnO, with the peak of the interference spectrum shifted by 2.3 nm and 5.2 nm, respectively, after injection of the two gases. This indicates that interferometric spectroscopy can serve as an effective tool for ZnO monitoring, capable of selectively detecting specific gases.

In this research, the extraction process of polysaccharides from Pithecellobium clypearia Benth (PCBPs) was optimized using dual-frequency ultrasound-assisted extraction (DUAE). The biological activities of PCBPs were investigated by in vitro antioxidant, hypoglycemic, and anti-hyperlipidemic assay. High-performance anion-exchange chromatography, high-performance gel permeation chromatography, SEM, UV–Vis spectroscopy, and FT-IR spectra were used to analyze the monosaccharide composition, molecular weight, microscopic morphology, and characteristic structure of PCBPs. The results showed that the maximum extraction rate of PCBPs was 9.90 ± 0.16% when the ultrasonic time was 8 min, the liquid-to-material ratio was 32 mL/g, and the ultrasonic power was 510 W. The PCBPs also possessed excellent in vitro antioxidant, hypoglycemic, and anti-hyperlipidemic activities. In addition, the average molecular weight of PCBPs was 15.07 kDa. PCBPs consisted of rhamnose, arabinose, galactose, glucose, xylose, mannose, and glucuronic acid, with the molar ratios of 11.07%, 18.54%, 48.17%, 10.44%, 4.62%, 4.96%, and 2.20%, respectively. Moreover, the results of SEM showed that PCBPs mainly showed a fine spherical mesh structure. The above studies provided a valuable theoretical basis for the subsequent in-depth study of PCBPs.

Litsea cubeba essential oil (LCEO) has garnered widespread attention due to its robust biological activity. However, challenges such as high volatility, limited water solubility, and low bioavailability impede its application. Nano-emulsion encapsulation technology offers an effective solution to these issues. In this study, we prepared litsea cubeba essential oil nano-emulsion (LCEO-NE) for the first time using whey protein (WP) as the emulsifier through an ultrasonic-assisted method, achieving high efficiency with minimal energy consumption. Transmission electron microscopy and dynamic light scattering analyses revealed that the nanoparticles were uniformly spherical, with a particle size of 183.5 ± 1.19 nm and a zeta potential of −35.5 ± 0.95 mV. Stability studies revealed that LCEO-NE exhibited excellent thermal and salt stability, maintaining its integrity for up to four weeks when stored at 4 °C and 25 °C. In vitro digestion assays confirmed the digestibility of LCEO-NE. Furthermore, evaluation of the DPPH, ABTS, and antimicrobial activities revealed that LCEO-NE displayed superior bacteriostatic and antioxidant properties compared to LCEO. Scanning electron microscopy elucidated that its bacteriostatic effect involved the disruption of bacterial microstructure. Hemocompatibility and cytotoxicity assays demonstrated the safety of LCEO-NE within the effective concentration range. This research supports the utilization of nanoparticles for encapsulating LCEO, thereby enhancing its stability and bioactivity, and consequently expanding its applications in the food and pharmaceutical industries.

Nucleoside free radicals have important functions in organisms and play a crucial role in DNA damage. Accurately understanding the structure of nucleoside free radicals is crucial for studying their properties, reaction mechanisms, and interactions with other biomolecules. The high vacuum in the mass spectrometer provides an inert environment for free radicals. Further tandem mass spectrometry combined with theoretical calculation is crucial for achieving their structural informations. This article reviewed gas phase studies of base and nucleoside radicals based on mass spectrometry in the past two decades, and provided a detailed introduction and comparison of their production methods, structural research methods and progress. Different methods were developed for the generation of the free radical ions, including collision induced dissociation of precursor ions of ternary transition metal complexes or those introducing free radical initiators, electron transfer dissociation of precursor ions charge-tagged, and UV photodissociation of precursor ions including C-I bonds. Besides, the methods for studying the structure of free radical ions in gas phase have gradually enriched, including commonly used tandem mass spectrometry, UV-visible and IR photodissociation spectroscopy. Based on the above methods, many different base and nucleoside free radical ions were generated and structurally determined in gas phase. On the other hand, the research of the highly active free radical intermediates and the selective generation of free radical isomers still pose challenges, and there is an urgent need to develop new experimental method.

Dust models are widely applied over the East Asian region for the simulation of dust emission, transport, and deposition. However, due to the uncertainties in estimates of dust transport, these methods still lack the necessary precision to capture the complexity of transboundary dust events. This study demonstrates an improvement in the Community Multiscale Air Quality (CMAQ) model dust treatment during long-range transport of dust from northwestern China to the South China Sea (SCS). To accomplish this, we considered a super dust storm (SDS) event in March 2010 and evaluated the dust scheme by including adjustments to the recent calibration (Dust_Refined_1) and bulk density (Dust_Refined_2) refinements individually and in combination (Dust_Refined_3). The Dust_Refined_3 normalized mean bias of PM10 was −30.65 % for the 2010 SDS event, which was lower in magnitude compared to Dust_Refined_1 (−41.18 %) and Dust_Refined_2 (−49.88 %). Indeed, Dust_Refined_3 improved the simulated aerosol optical depth (AOD) value during significant dust cases, e.g., in March 2005, March 2006, and April 2009. Dust_Refined_3 also showed more clearly that, in March 2010, a “double plume” (i.e., one plume originating from the Taiwan Strait and the other from the western Pacific) separated by the Central Mountain Range (CMR) of Taiwan affected dust transport on the island of Dongsha in the SCS. On 15–21 April 2021, both CMAQ simulations and satellite data highlighted the influence of Typhoon Surigae on dust transport to downwind Taiwan and the western Pacific Ocean (WPO). The CMAQ Dust_Refined_3 simulations further revealed that many dust aerosols were removed over the WPO due to Typhoon Surigae. Hence, the model indicated a near-zero dust particle concentration over the WPO, which was significantly different from previous dust transport episodes over the Taiwan region. Therefore, our study suggested an effective method to improve dust management of CMAQ under unique topographical and meteorological conditions.

Psoriasis, characterized by erythematous plaques, desquamation, persistent pruritus, and discomfort, significantly compromises the quality of life for afflicted individuals. The intricate interplay of immunological, genetic, and environmental factors has left the molecular intricacies of psoriasis only partially elucidated, underscoring the imperative to unravel these intricate mechanisms. In contradistinction to conventional techniques such as nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LC-MS), the burgeoning laser desorption/ionization (LDI) metabolic paradigm holds substantial promise in elucidating the molecular mechanism of psoriasis. Nonetheless, achieving heightened sensitivity and high-throughput metabolite detection within intricate clinical biosamples mandates stringent requisites, encompassing favourable ionization efficiency and high surface area. Henceforth, we proffered a dual-strategy entailing the utilization of transition metal carbides (MXene) with unique morphology and the integration of multi-walled carbon nanotubes (MWCNTs) to ameliorate these challenges for psoriasis. We have corroborated the morphological architecture, elemental composition, and efficacy of LDI when applied to MWCNTs-doped MXene. Egregiously, through the employment of both animal models and clinical specimens, we attained diagnostic efficiencies of 0.959 and 0.924 via receiver operating characteristic (ROC) curve analysis, respectively, for discrimination psoriasis from control individuals. Doped MXene evinced exceptional signal amplification and imperviousness to salt and protein interference. Furthermore, enrichment pathway analysis unveiled a significant escalation in leukotriene E4 and arachidonic acid levels within the psoriasis cohort. Harnessing LDI metabolic fingerprints, concomitant with MWCNTs-doped MXene, expedited the recognition of the distinct metabolic characteristics inherent to psoriasis, thereby laying bare the dysregulation in leukotriene metabolism. This epochal breakthrough holds immense potential to usher in new vistas for exploring the underlying mechanisms governing the onset and progression of psoriasis-related disorders, thereby significantly contributing to the refinement of psoriasis health management strategies.

Rechargeable zinc (Zn) metal batteries have long been plagued by dendrite growth and parasitic reactions due to the absence of a stable Zn-ion conductive solid-electrolyte interphase (SEI). Although the current strategies assist in suppressing dendritic Zn growth, it is still a challenge to obtain the operation-stability of Zn anode with high Coulombic efficiency (CE) required to implement a sustainable and long-cycling life of Zn metal batteries. In this perspective, we summarize the advantages of the functional gradient interphase (FGI) and try to fundamentally understand the transport behaviors of Zn ions, based on recently an article understanding Zn chemistry. The correlation between the function-orientated design of gradient interphase and key challenges of Zn metal anodes in accelerating Zn2+ transport kinetics, improving electrode reversibility, and inhibiting Zn dendrite growth and side reactions was particularly emphasized. Finally, the rational design and innovative directions are provided for the development and application of functional gradient interphase in rechargeable Zn metal battery systems.

Abstract Silver/polymeric vesicle composite nanoparticles with good antibacterial properties were fabricated in this study. Silver nanoparticles (AgNPs) were prepared in situ on cross‐linked vesicle membranes through the reduction of silver nitrate (AgNO3) using polyvinylpyrrolidone (PVP) via coordination bonding between the Ag+ ions and the nitrogen atoms on the vesicles. X‐ray diffraction (XRD), ultraviolet‐visible spectroscopy (UV‐vis), and transmission electron microscopy (TEM) analyses confirmed the formation of AgNPs on the vesicles. The antibacterial test demonstrated good antibacterial activity against both Gram‐negative bacteria (Escherichia coli) and Gram‐positive bacteria (Staphylococcus aureus) for the produced AgNP‐decorated vesicles. The minimum inhibitory concentration (MIC) values of the AgNP‐decorated vesicles for E. coli and S. aureus were 8.4 and 9.6 μg/mL, respectively. Cell viability analysis on the A549 cells indicated that the toxicity was low when the AgNP concentrations did not exceed the MIC values, and the wound healing test confirmed the good antibacterial properties of the AgNP‐decorated vesicles.

Multidrug resistance (MDR) is the major challenge for chemotherapy of cancer and makes the treatment benefits unsustainable. To overcome this issue, nanotechnology has been introduced and various nanocarriers have been constructed to reverse MDR in drug resistant cancer cells. Here, mesoporous silica nanoparticle (MSN-COOH) were modified with cationic anticancer peptide L-K6 (MSN@L-K6), and further loaded with doxorubicin (DOX) to construct an anticancer nano-system, MSN@L-K6@DOX. Our results showed that MSN@L-K6@DOX released DOX in pH-sensitive manner, which enable to be highly efficient in delivering drugs to tumors, counterbalancing the MDR. In addition, MSN@L-K6@DOX treatment decreased the expression level of P-glycoprotein in MCF-7/ADR cells, enhanced the intracellular accumulation of DOX, and thereafter reversed the MDR of MCF-7/ADR cells to DOX. Moreover, the MDR reversal activity of MSN@L-K6@DOX was further confirmed in xenograft mouse model, as evidenced by the decreased tumor volume and weight. These results indicate the MDR reversal activity of MSN@L-K6@DOX and may provide a novel strategy for the development of nano-based drug delivery system to overcome cancer MDR.

Abstract Colloidal crystals are materials self‐assembled from the colloidal nanoparticles. Due to the ordered microstructure, they exhibit significant optical properties and have shown huge potential in the field of biosensing. Besides, the unique macroscopic shapes can also play a critical role in the sensing process. Here, we present a comprehensive discussion on the colloidal crystal‐based biosensors with different topological shapes, including the development strategies of currently reported colloidal crystal particles, films, and fibers, and their recent progress in biosensing. In addition, the faced challenges and the possible solutions are also concluded and discussed. We expect this review can enrich the knowledge and encourage the communication of interdisciplinary researchers, thus promoting the further development and practical applications of colloidal crystal‐based biosensors.

Abstract Developing low‐cost and safe batteries with high energy density is promising for large‐scale energy storage applications. Currently, aqueous zinc ion batteries (AZIBs) using Zn metal as the anode have attracted tremendous research attention as the next generation of energy storage devices due to their advantages of high energy density, environmental friendliness, and natural Zn abundance. The utilization of synchrotron X‐ray analytical techniques for in situ/ex situ characterizations offers a comprehensive understanding of the atomic local structure, crystalline structure, chemical states, coordination environment, interface properties, morphologies, and other physicochemical properties of materials on a variety of temporal and length scales, providing valuable insights into the fundamental mechanisms of AZIBs. This review highlights the recent advances and accomplishments of various synchrotron X‐ray techniques, which have been employed to investigate different components of AZIBs and show great promise for battery research and development.

Background: Amino acids (AAs) metabolism profiles in brain play a pivotal role in cerebral ischemia (CI), which is a complex, spatial and temporal event. NaoXinTong Capsules (NXT) are widely prescribed in Chinese medicine for the treatment of cerebrovascular and cardiovascular diseases. Methods: In this study, a novel analytical method for the quantification of twenty-three AAs in cortex and hippocampus was developed by UPLC-QQQ-MS. Based on middle cerebral artery occlusion (MCAO) rat model, the cerebral infarction and the neurological behavior scores are firstly dynamically evaluated at 3, 12, and 24 h after CI. Then the dynamic levels of the AAs in cortex and hippocampus were analyzed respectively after CI. Results: After CI, MCAO rats showed neurological deficits especially at 24 h. Based on PCA scores plot at different time after CI, the time of the AAs metabolism showing an obvious disturbance in the cortex (12 and 24 h after ischemia) is earlier than that in the hippocampus (24 h after ischemia). Based on the fold-changes of MCAO vs. sham group and receiver operating curve (ROC) analysis, a total of nine AAs biomarkers, with continuous and consistent changes at different time points after CI, were finally obtained including eight AAs of Ala, GABA, Pro, Val, Ile, His, Cit and Leu in the cortex, and three AAs of Ile, Asp, and Cit in the hippocampus. After NXT treatment, the efficacy was confirmed by reducing cerebral infarction and improving the neurological behavior scores. Furthermore, GABA, Pro, His, Leu, Asp, Ile and Cit were found to exhibited an obvious tendency for returning to baseline values in the corresponding regions at 24 h after CI (P

Sepsis is a common and deadly syndrome that despite all the progress in its control, the death rate caused by it is high. Sepsis is a serious problem that needs immediate attention and treatment. This infection, especially if it is caused by bacteria resistant to several drugs, causes high mortality. About two-thirds of sepsis cases occur in hospitalized patients. Several factors such as increasing the age of the population, increasing the duration of chronic diseases, high consumption of antibiotics and corticosteroids, use of mechanical devices and intravascular devices play a role in increasing its incidence. We herein demonstrate the biogenic procedure for the in situ immobilizing gold nanoparticles over lignin (Lig)-modified Fe3O4 magnetic nanoparticles mediated by Cydonia leaf extract (Fe3O4@Lig-Ag NPs) and its catalytic activity on the acetylation of alcohols using acetic anhydride and subsequent biological performances. The successful synthesis of Fe3O4@Lig-Ag NPs was assessed using an array of advanced techniques like field emission scanning electron microscopy, fourier transformed infrared spectroscopy, transmission electron microscopy EDX, elemental mapping, vibrating-sample magnetometer, and X-ray diffraction. Cecal ligation and puncture was used for inducing the sepsis model in rats. Several doses of Fe3O4@Lig-Ag NPs (45, 15, and 5 µg/kg) on oxidant–antioxidant, inflammatory mediators mRNA such as IL-1 and TNF-α, and its effects on the levels of expression were assessed in the kidney, liver, duodenum, lung, and stomach. When septic rats kidney, liver, duodenum, lung, and stomach were compared with those of the control group, it was found that Fe3O4@Lig-Ag NPs dose-dependent administration raised glutathione levels and superoxide dismutase activity and significantly reduced the levels of malondialdehyde. The Fe3O4@Lig-Ag NPs (45 µg/kg) indicated greater anti-oxidative effects than the 5 and 15 µg/kg doses for all the assessed parameters. In addition, the expression of TNF-α mRNA in the CLP + 45 µg/kg group was decreased in comparison with the control group. Fe3O4@Lig-Ag NPs reduced oxidative stress by enhancing the free radicals scavenging effects and supporting endogenous antioxidants. The Fe3O4@Lig-Ag NPs potent antioxidant property may be related to the cytokine cascade suppression during sepsis. The above findings offer that Fe3O4@Lig-Ag NPs administration may indicate a modern treatment for the inhibition of liver, kidney, lung, duodenum, and stomach tissues damage caused by septic conditions.

Abstract Pregnancy-Associated Plasma Protein A isoforms, PAPP-A and PAPP-A2, are metalloproteases that cleave insulin-like growth factor binding proteins (IGFBPs) to modulate insulin-like growth factor signaling. The structures of homodimeric PAPP-A in complex with IGFBP5 anchor peptide, and inhibitor proteins STC2 and proMBP have been recently reported. Here, we present the single-particle cryo-EM structure of the monomeric, N-terminal LG, MP, and the M1 domains (with the exception of LNR1/2) of human PAPP-A2 to 3.13 Å resolution. Our structure together with functional studies provides insight into a previously reported patient mutation that inactivates PAPP-A2 in a distal region of the protein. Using a combinational approach, we suggest that PAPP-A2 recognizes IGFBP5 in a similar manner as PAPP-A and show that PAPP-A2 cleaves IGFBP5 less efficiently due to differences in the M2 domain. Overall, our studies characterize the cleavage mechanism of IGFBP5 by PAPP-A2 and shed light onto key differences with its paralog PAPP-A.

Determining the advanced mining influence range of an underground working face is crucial for preventing dynamic disasters, such as coal bursts and gas outbursts. In this study, the occurrence of advanced seismicity before the working face as well as its correlation with the acoustic emission (AE) activity of coal and rocks under axial loading was analyzed. Based on the results, a novel statistical method to determine the advanced mining influence range based on advanced seismicity data was proposed and then validated with a case study. The results show that advanced seismicity is caused by the combined effects of static and dynamic stresses at the working face. This seismicity can be used to assess the mining influence degree of the working face on the advanced coal and rock mass, and determine the advanced mining influence range. Using the novel statistical method, the normalized curves for the total number and total energy of the advanced mining-induced seismicity can be plotted. Then, the advanced mining influence range can be determined using thresholds. The thresholds can be established based on the AE activities observed in coal and rock samples under axial static loading. In the case study in this research, the thresholds for the total seismic number and total seismic energy are 0.076 and 0.052, respectively. The corresponding advanced mining influence ranges are 275 m and 245 m, respectively. Field monitoring confirms an advanced mining influence range of 255 m, which validates the results obtained using the novel statistical method.

Multi-focal image and multi-modal image fusion technology can fully take advantage of different sensors or different times, retaining the image feature information and improving the image quality. A multi-source image fusion algorithm based on bidimensional empirical mode decomposition (BEMD) and a region sharpness-guided region overlapping algorithm are studied in this article. Firstly, source images are decomposed into multi-layer bidimensional intrinsic mode functions (BIMFs) and residuals from high-frequency layer to low-frequency layer by BEMD. Gaussian bidimensional intrinsic mode functions (GBIMFs) are obtained by applying Gaussian filtering operated on BIMF and calculating the sharpness value of segmented regions using an improved weighted operator based on the Tenengrad function, which is the key to comparison selection and fusion. Then, the GBIMFs and residuals selected by sharpness comparison strategy are fused by the region overlapping method, and the stacked layers are weighted to construct the final fusion image. Finally, based on qualitative evaluation and quantitative evaluation indicators, the proposed algorithm is compared with six typical image fusion algorithms. The comparison results show that the proposed algorithm can effectively capture the feature information of images in different states and reduce the redundant information.

The bHLH (basic helix–loop–helix) transcription factor AtCFLAP2 regulates epidermal wax accumulation, but the underlying molecular mechanism remains unknown. We obtained BnUC1mut (BnaA05g18250D homologous to AtCFLAP2) from a Brassica napus mutant with up-curling leaves (Bnuc1) and epidermal wax deficiency via map-based cloning. BnUC1mut contains a point mutation (N200S) in the conserved dimerization domain. Overexpressing BnUC1mut in ZS11 (Zhongshuang11) significantly decreased the leaf epidermal wax content, resulting in up-curled and glossy leaves. In contrast, knocking out BnUC1mut in ZS11-NIL (Zhongshuang11-near-isogenic line) restored the normal leaf phenotype (i.e., flat) and significantly increased the leaf epidermal wax content. The point mutation weakens the ability of BnUC1mut to bind to the promoters of VLCFA (very-long-chain fatty acids) synthesis-related genes, including KCS (β-ketoacyl coenzyme synthase) and LACS (long-chain acyl CoA synthetase), as well as lipid transport-related genes, including LTP (non-specific lipid transfer protein). The resulting sharp decrease in the transcription of genes affecting VLCFA biosynthesis and lipid transport disrupts the normal accumulation of leaf epidermal wax. Thus, BnUC1 influences epidermal wax formation by regulating the expression of LTP and genes associated with VLCFA biosynthesis. Our findings provide a foundation for future investigations on the mechanism mediating plant epidermal wax accumulation.

Cotton fiber is the leading natural textile material, and fiber elongation plays an essential role in the formation of cotton yield and quality. Although a number of components in the molecular network controlling cotton fiber elongation have been reported, a lot of players still need to be functionally dissected to understand the regulatory mechanism of fiber elongation comprehensively. In the present study, an R2R3-MYB transcription factor gene, GhMYB201, was characterized and functionally verified via CRISPR/Cas9-mediated gene editing. GhMYB201 was homologous to Arabidopsis AtMYB60, and both coding genes (GhMYB201At and GhMYB201Dt) were preferentially expressed in elongating cotton fibers. Knocking-out of GhMYB201 significantly reduced the rate and duration of fiber elongation, resulting in shorter and coarser mature fibers. It was found that GhMYB201 could bind and activate the transcription of cell wall loosening genes (GhRDLs) and also β-ketoacyl-CoA synthase genes (GhKCSs) to enhance very-long-chain fatty acid (VLCFA) levels in elongating fibers. Taken together, our data demonstrated that the transcription factor GhMYB201s plays an essential role in promoting fiber elongation via activating genes related to cell wall loosening and VLCFA biosynthesis.

The lateral root (LR) is an essential component of the plant root system, performing important functions for nutrient and water uptake in plants and playing a pivotal role in cereal crop productivity. Nitrate (NO3−) is an essential nutrient for plants. In this study, wheat plants were grown in 1/2 strength Hoagland’s solution containing 5 mM NO3− (check; CK), 0.1 mM NO3− (low NO3−; LN), or 0.1 mM NO3− plus 60 mg/L 2,3,5-triiodobenzoic acid (TIBA) (LNT). The results showed that LN increased the LR number significantly at 48 h after treatment compared with CK, while not increasing the root biomass, and LNT significantly decreased the LR number and root biomass. The transcriptomic analysis showed that LN induced the expression of genes related to root IAA synthesis and transport and cell wall remodeling, and it was suppressed in the LNT conditions. A physiological assay revealed that the LN conditions increased the activity of IAA biosynthesis-related enzymes, the concentrations of tryptophan and IAA, and the activity of cell wall remodeling enzymes in the roots, whereas the content of polysaccharides in the LRP cell wall was significantly decreased compared with the control. Fourier-transform infrared spectroscopy and atomic microscopy revealed that the content of cell wall polysaccharides decreased and the cell wall elasticity of LR primordia (LRP) increased under the LN conditions. The effects of LN on IAA synthesis and polar transport, cell wall remodeling, and LR development were abolished when TIBA was applied. Our findings indicate that NO3− starvation may improve auxin homeostasis and the biological properties of the LRP cell wall and thus promote LR initiation, while TIBA addition dampens the effects of LN on auxin signaling, gene expression, physiological processes, and the root architecture.

Due to limited drug efficacy and drug resistance, it is urgent to explore effective anti-liver cancer drugs. Repurposing drugs is an efficient strategy, with advantages including reduced costs, shortened development cycles, and assured safety. In this study, we adopted a synergistic approach combining computational and experimental methods and identified the antibacterial drug thiostrepton (TST) as a candidate for an anti-liver cancer drug. Although the anti-tumor capabilities of TST have been reported, its role and underlying mechanisms in hepatocellular carcinoma (HCC) remain unclear. TST was found here to inhibit the proliferation of HCC cells effectively, arresting the cell cycle and inducing cell apoptosis, as well as suppressing the cell migration. Further, our findings revealed that TST induced mitochondrial impairment, which was demonstrated by destroyed mitochondrial structures, reduced mitochondria, and decreased mitochondrial membrane potential (MMP). TST caused the production of reactive oxygen species (ROS), and the mitochondrial impairment and proliferation inhibition of HCC cells were completely restored by the ROS scavenger N-acetyl-L-cysteine (NAC). Moreover, we discovered that TST induced mitophagy, and autophagy inhibition effectively promoted the anti-cancer effects of TST on HCC cells. In conclusion, our study suggests TST as a promising candidate for the treatment of liver cancers, and these findings provide theoretical support for the further development and potential application of TST in clinical liver cancer therapy.

Bacteriocins are a class of proteins produced by bacteria that are toxic to other bacteria. These bacteriocins play a role in bacterial competition by helping to inhibit potential competitors. In this study, we isolated and purified a novel bacteriocin Pkmh, different from the previously reported bacteriocin PA166, from Pseudomonas sp. strain 166 by ammonium sulfate precipitation, dialysis membrane method, ion exchange chromatography, and gel filtration chromatography. SDS-PAGE (sodium dodecyl sulfate–polyacrylamide gel electrophoresis) revealed that the molecular weight of Pkmh is approximately 35 kDa. Pkmh exhibited potent antimicrobial activity against bovine Mannheimia haemolytica (M. haemolytica) with low cytotoxicity, and lower hemolytic activity was observed. In addition, Pkmh retained antimicrobial activity at different pH ranges (2–10) and temperature conditions (40, 60, 80, 100 °C). Our analysis of its antimicrobial mechanism showed that Pkmh acts on bacterial cell membranes, increasing their permeability and leading to cell membrane rupture and death. In conclusion, Pkmh exhibited low hemolytic activity, low toxicity, and potent antibacterial effects, suggesting its potential as a promising candidate for clinical therapeutic drugs.

The alternative oxidase (AOX), a common terminal oxidase in the electron transfer chain (ETC) of plants, plays a crucial role in stress resilience and plant growth and development. Oat (Avena sativa), an important crop with high nutritional value, has not been comprehensively studied regarding the AsAOX gene family. Therefore, this study explored the responses and potential functions of the AsAOX gene family to various abiotic stresses and their potential evolutionary pathways. Additionally, we conducted a genome-wide analysis to explore the evolutionary conservation and divergence of AOX gene families among three Avena species (Avena sativa, Avena insularis, Avena longiglumis) and four Poaceae species (Avena sativa, Oryza sativa, Triticum aestivum, and Brachypodium distachyon). We identified 12 AsAOX, 9 AiAOX, and 4 AlAOX gene family members. Phylogenetic, motif, domain, gene structure, and selective pressure analyses revealed that most AsAOXs, AiAOXs, and AlAOXs are evolutionarily conserved. We also identified 16 AsAOX segmental duplication pairs, suggesting that segmental duplication may have contributed to the expansion of the AsAOX gene family, potentially preserving these genes through subfunctionalization. Chromosome polyploidization, gene structural variations, and gene fragment recombination likely contributed to the evolution and expansion of the AsAOX gene family as well. Additionally, we hypothesize that AsAOX2 may have potential function in resisting wounding and heat stresses, while AsAOX4 could be specifically involved in mitigating wounding stress. AsAOX11 might contribute to resistance against chromium and waterlogging stresses. AsAOX8 may have potential fuction in mitigating ABA-mediated stress. AsAOX12 and AsAOX5 are most likely to have potential function in mitigating salt and drought stresses, respectively. This study elucidates the potential evolutionary pathways of the AsAOXs gene family, explores their responses and potential functions to various abiotic stresses, identifies potential candidate genes for future functional studies, and facilitates molecular breeding applications in A. sativa.