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In areas affected by arsenicosis, zerovalent iron (ZVI)/sand filters are extensively used by households to treat groundwater, but ZVI surface passivation and filter clogging limit their arsenic (As) removal performance. Here we present a magnetic confinement-enabled column reactor coupled with periodic ultrasonic depassivation (MCCR-PUD), which efficiently and sustainably removes As by reaction with continuously generated iron (oxyhydr)oxides from ZVI oxidative corrosion. In the MCCR, ZVI microparticles self-assemble into stable millimeter-scale wires in forest-like arrays in a parallel magnetic field (0.42-0.48 T, produced by two parallel permanent magnets), forming a highly porous structure (87 % porosity) with twice the accessible reactive surface area of a ZVI/sand mixture. For a feed concentration of 100 µg/L As(III), the MCCR-PUD, with a short empty bed contact time (1.6 min), treated ca. 7340 empty bed volume (EBV) of water at breakthrough (10 µg/L), 9.4 folds higher than that of a ZVI/sand filter. Due to the large interspace between ZVI wires, the MCCR-PUD effectively prevented column clogging that occurred in the ZVI/sand filter. The high water treatment capacity was attributed to the much enhanced ZVI reactivity in the magnetic field, sustained through rejuvenation by PUD. Furthermore, most of As was structurally incorporated into the produced iron (oxyhydr)oxides (mostly ferrihydrite) in the MCCR-PUD, as revealed by Mössbauer spectroscopy, X-ray absorption spectroscopy, and sequential extraction experiments. This finding evinced a different mechanism from the surface adsorption in the ZVI/sand filter. The structural incorporation of As also resulted in much less As remobilization from the produced corrosion products during aging in water, in total â¼1 % in 28 days. Furthermore, the MCCR-PUD exihibted robust performance when treating complex synthetic groundwater containing natural organic matter and common ions (â¼3700 EBV at breakthrough). Taken together, our study demonstrates the potential of the magnetic confinement-enabled ZVI reactor as a promising decentralized As treatment platform.
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Purpose: Due to intrinsic defensive response, ferroptosis-activating targeted therapy fails to achieve satisfactory clinical benefits. Though p62-Keap1-Nrf2 axis is activated to form a negative feedback loop during ferroptosis induction, how p62 is activated remains largely unknown. Methods: MTS assay was applied to measure cell growth. Lipid ROS was detected with C11-BODIPY reagent by flow cytometer. Quantitative real-time PCR (qPCR) and western blotting were performed to determine mRNA and protein level. Immunofluorescence (IF) was performed to examine the distribution of proteins. Fluorescence recovery after photobleaching (FRAP) was adopted to evaluate p62 phase separation. Immunoprecipitation (IP), co-IP and Proximal ligation assay (PLA) were performed to detected protein posttranslational modifications and protein-protein interactions. Tumor xenograft model was employed to inspect in vivo growth of pancreatic cancer cells. Results: Upon ferroptosis induction, Nuclear Factor E2 Related Factor 2 (Nrf2) protein and its downstream genes such as HMOX1 and NQO1 were upregulated. Knockdown of p62 significantly reversed Nrf2 upregulation and Keap1 decrease after ferroptosis induction. Knockdown of either p62 or Nrf2 remarkably sensitized ferroptosis induction. Due to augmented p62 phase separation, formation of p62 bodies were increased to recruit Keap1 after ferroptosis induction. Protein arginine methyltransferase 6 (PRMT6) mediated asymmetric dimethylarginine (ADMA) of p62 to increase its oligomerization, promoting p62 phase separation and p62 body formation. Knockdown of p62 or PRMT6 notably sensitized pancreatic cancer cells to ferroptosis both in vitro and in vivo through suppressing Nrf2 signaling. Conclusion: During ferroptosis induction, PRMT6 mediated p62 ADMA to promote its phase separation, sequestering Keap1 to activate Nrf2 signaling and inhibit ferroptosis. Therefore, targeting PRMT6-mediated p62 ADMA could be a new option to sensitize ferroptosis for cancer treatment.
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Arginina , Ferroptosis , Proteína 1 Asociada A ECH Tipo Kelch , Factor 2 Relacionado con NF-E2 , Proteína-Arginina N-Metiltransferasas , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Humanos , Animales , Arginina/metabolismo , Arginina/análogos & derivados , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Ratones , Línea Celular Tumoral , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/genética , Retroalimentación Fisiológica , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Proteína Sequestosoma-1/metabolismo , Proteína Sequestosoma-1/genética , Ratones Desnudos , Transducción de Señal , Separación de Fases , Proteínas de Unión al ARNRESUMEN
The properties of nanopipettes largely rely on the materials introduced onto their inner walls, which allow for a vast extension of their sensing capabilities. The challenge of simultaneously enhancing the sensitivity and selectivity of nanopipettes for pH sensing remains, hindering their practical applications. Herein, we report insulin-modified nanopipettes with excellent pH response performances, which were prepared by introducing insulin onto their inner walls via a two-step reaction involving silanization and amidation. The pH response intensity based on ion current rectification was significantly enhanced by approximately 4.29 times when utilizing insulin-modified nanopipettes compared with bare ones, demonstrating a linear response within the pH range of 2.50 to 7.80. In addition, insulin-modified nanopipettes featured good reversibility and selectivity. The modification processes were monitored using the I-V curves, and the relevant mechanisms were discussed. The effects of solution pH and insulin concentration on the modification results were investigated to achieve optimal insulin introduction. This study showed that the pH response behavior of nanopipettes can be greatly improved by introducing versatile molecules onto the inner walls, thereby contributing to the development and utilization of pH-responsive nanopipettes.
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Insulina , Concentración de Iones de Hidrógeno , Insulina/química , Técnicas Biosensibles/métodos , Iones/químicaRESUMEN
Drought stress is a major limit on the maize growth and productivity, and understanding the drought response mechanism is one of the important ways to improve drought resistance in maize. However, more drought-related genes and their regulated mechanisms are still to be reported. Here, we identified a novel NAC transcription factor ZmNAC55 in Zea mays and comprehensively investigated the functions of ZmNAC55 under drought stress. ZmNAC55 belonged to the NAP subfamily. ZmNAC55 had a conserved NAC domain in the N-terminal region and a divergent TAR region in the C-terminal region. ZmNAC55 was a nuclear protein, and ZmNAC55 and its TAR region had the transcriptional activation activity. Furthermore, the expression level of ZmNAC55 in leaves could be highly induced by drought stress. ZmNAC55 overexpression in Arabidopsis conferred the drought-sensitive phenotype with higher water loss, lower survival rate, higher membrane ion leakage, and higher expression levels of some drought-related genes. Meanwhile, ZmNAC55 underexpression in maize enhanced drought tolerance with lower water loss, higher survival rate, lower membrane ion leakage and lower expression levels of some drought-related genes. In addition, ZmNAC55 appeared to be very key in regulating ROS production under drought stress. Moreover, ZmNAC55 could activate ZmHOP3 expression by binding to its promoter. A novel working model of ZmNAC55 under drought stress could be found in maize. Taken together, the NAC transcription factor ZmNAC55 could negatively regulate drought stress via increasing ZmHOP3 expression in maize. ZmNAC55 is a promising candidate for improving drought resistance in maize.
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Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Factores de Transcripción , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Sequías , Plantas Modificadas Genéticamente , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiología , Estrés Fisiológico/genética , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Background: Over the past few decades, antimicrobial resistance (AMR) has emerged as a global health challenge in human and veterinary medicine. Research on AMR genes in captive wild animals has increased. However, the presence and molecular characteristics of tet(X)-carrying bacteria in these animals remain unknown. Methods: Eighty-four samples were collected from captive wild animals. tet(X) variants were detected using polymerase chain reaction and the isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. All isolated strains were subjected to antimicrobial susceptibility testing and whole-genome sequencing. The virulence of an Escherichia coli strain carrying enterotoxin genes was assessed using a Galleria mellonella larval model. Results: We isolated two tet(X4)-positive E. coli strains and one tet(X4)-positive Raoultella ornithinolytica strain. Antimicrobial susceptibility tests revealed that all three tet(X4)-carrying bacteria were sensitive to the 13 tested antimicrobial agents, but exhibited resistance to tigecycline. Notably, one tet(X4)-carrying E. coli strain producing an enterotoxin had a toxic effect on G. mellonella larvae. Whole-genome sequencing analysis showed that the two tet(X4)-carrying E. coli strains had more than 95% similarity to tet(X4)-containing E. coli strains isolated from pigs and humans in China. Conclusion: The genetic environment of tet(X4) closely resembled that of the plasmid described in previous studies. Our study identified tet(X4)-positive strains in wildlife and provided valuable epidemiological data for monitoring drug resistance. The identification of enterotoxin-producing E. coli strains also highlights the potential risks posed by virulence genes.
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Silicones have excellent material properties and are used extensively in many applications, ranging from adhesives and lubricants to electrical insulation. To ensure strong adhesion of silicone adhesives to a wide variety of substrates, silane-based adhesion promotors are typically blended into the silicone adhesive formulation. However, little is known at the molecular level about the true silane adhesion promotion mechanism, which limits the ability to develop even more effective adhesion promoters. To understand the adhesion promotion mechanism of silane molecules at the molecular level, this study has used sum frequency generation vibrational spectroscopy (SFG) to determine the behavior of (3-glycidoxypropyl)trimethoxy silane (γ-GPS) at the buried interface between poly(ethylene terephthalate) (PET) and a bulk silicone adhesive. To complement and extend the SFG results, atomistic molecular dynamics (MD) simulations were applied to investigate molecular behavior and interfacial interaction of γ-GPS at the silicone/PET interface. Free energy computations were used to study the γ-GPS interaction in the sample system and determine the γ-GPS interfacial segregation mechanism. Both experiments and simulations consistently show that γ-GPS molecules prefer to segregate at the interface between PET and PDMS. The methoxy groups on γ-GPS molecules orient toward the PDMS polymer phase. The consistent picture of interfacial structure emerging from both simulation and experiment provides enhanced insight on how γ-GPS behaves in the silicone - PET system and illustrates why γ-GPS could improve the adhesion of silicone adhesive, leading to further understanding of silicone adhesion mechanisms useful in the design of silicone adhesives with improved performance.
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Maleic anhydride (MAH)-modified polymers are used as tie layers for binding dissimilar polymers in multilayer polymer films. The MAH chemistry which promotes adhesion is well characterized in the bulk; however, only recently has the interfacial chemistry been studied. Sum frequency generation vibrational spectroscopy (SFG) is an interfacial spectroscopy technique which provides detailed information on interfacial chemical reactions, species, and molecular orientations and has been essential for characterizing the MAH chemistry in both nylon and ethyl vinyl alcohol copolymer (EVOH) model systems and coextruded multilayer films. Here, we further characterize the interfacial chemistry between MAH-modified polyethylene tie layers and both EVOH and nylon by investigating the model systems over a range of MAH concentrations. We can detect the interfacial chemical reaction products between MAH and the barrier layer at MAH concentrations of ≥0.022 wt % for nylon and ≥0.077 wt % for EVOH. Additionally, from the concentration-dependent reaction reactant/product SFG peak positions and the product imide or ester/acid CâO group tilt angles extracted from the polarization-dependent SFG spectra, we quantitatively observe concentration-dependent changes to both the interfacial chemistry and interfacial structure. The interfacial chemistry and molecular orientation as a function of MAH concentration are well correlated with the adhesion strength, providing important quantitative information for the future design of MAH-modified tie layers for a variety of important applications.
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OBJECTIVES: This study aimed to explore the value of D-dimer levels in predicting the treatment efficacy and prognosis of advanced esophageal squamous cell carcinoma (ESCC) treated with programmed cell death protein-1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors. METHODS: The study retrospectively analyzed 233 ESCC patients who received PD-1/PD-L1 inhibitors. The optimal cut-off values for platelets, fibrinogen, and D-dimer were calculated based on maximally selected rank statistics for patients' overall survival. Univariate and multivariate analyses of progression-free survival and overall survival were conducted by Cox proportional hazards regression model. Subgroup analyses of D-dimer levels in different fibrinogen levels were performed by log-rank test. RESULTS: The multivariate Cox regression analyses demonstrated that ESCC patients with D-dimer levels > 236 ng/mL exhibited both poorer progression-free survival (P = 0.004) and overall survival (P < 0.0001) compared to those with low D-dimer levels. The subgroup analyses further indicated that in the group of low fibrinogen levels, the higher D-dimer levels of ESCC patients exhibited significantly shorter progression-free survival (P = 0.0021) and overall survival (P < 0.0001). CONCLUSIONS: The study revealed that the D-dimer levels possess predictive value for the treatment efficacy and prognosis of ESCC patients treated with PD-1/PD-L1 inhibitors.
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Chiral three-dimensional (3D) perovskites exhibit exceptional optoelectronic characteristics and inherent chiroptical activity, which may overcome the limitations of low-dimensional chiral optoelectronic devices and achieve superior performance. The integrated chip of high-performance arbitrary polarized light detection is one of the aims of chiral optoelectronic devices and may be achieved by chiral 3D perovskites. Herein, we first fabricate the wafer-scale integrated full-Stokes polarimeter by the synergy of unprecedented chiral 3D perovskites (R/S-PyEA)Pb2Br6 and one-step capillary-bridge assembly technology. Compared with the chiral low-dimensional perovskites, chiral 3D perovskites present smaller exciton binding energies of 57.3 meV and excellent circular dichroism (CD) absorption properties, yielding excellent circularly polarized light (CPL) photodetectors with an ultrahigh responsivity of 86.7 A W-1, an unprecedented detectivity exceeding 4.84 × 1013 Jones, a high anisotropy factor of 0.42, and high-fidelity CPL imaging with 256 pixels. Moreover, the anisotropic crystal structure also enables chiral 3D perovskites to have a large linear-polarization response with a polarized ratio of 1.52. The combination of linear-polarization and circular-polarization discrimination capabilities guarantees the achievement of a full-Stokes polarimeter. Our study provides new research insights for the large-scale patterning wafer integration of high-performance chiroptical devices.
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Terpene synthases (TPSs) are enzymes responsible for catalyzing the production of diverse terpenes, the largest class of secondary metabolites in plants. Here, we identified 107 TPS gene loci encompassing 92 full-length TPS genes in upland cotton (Gossypium hirsutum L.). Phylogenetic analysis showed they were divided into six subfamilies. Segmental duplication and tandem duplication events contributed greatly to the expansion of TPS gene family, particularly the TPS-a and TPS-b subfamilies. Expression profile analysis screened out that GhTPSs may mediate the interaction between cotton and Verticillium dahliae. Three-dimensional structures and subcellular localizations of the two selected GhTPSs, GhTPS6 and GhTPS47, which belong to the TPS-a subfamily, demonstrated similarity in protein structures and nucleus and cytoplasm localization. Virus-induced gene silencing (VIGS) of the two GhTPSs yielded plants characterized by increased wilting and chlorosis, more severe vascular browning, and higher disease index than control plants. Additionally, knockdown of GhTPS6 and GhTPS47 led to the down-regulation of cotton terpene synthesis following V. dahliae infection, indicating that these two genes may positively regulate resistance to V. dahliae through the modulation of disease-resistant terpene biosynthesis. Overall, our study represents a comprehensive analysis of the G. hirsutum TPS gene family, revealing their potential roles in defense responses against Verticillium wilt.
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Transferasas Alquil y Aril , Resistencia a la Enfermedad , Gossypium , Filogenia , Enfermedades de las Plantas , Proteínas de Plantas , Gossypium/genética , Gossypium/microbiología , Gossypium/enzimología , Gossypium/metabolismo , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Ascomicetos , VerticilliumRESUMEN
Understanding the spatial and temporal distribution of small water bodies is essential for managing water resources, crafting conservation policies, and preserving watershed ecosystems and biodiversity. However, existing studies often rely on a single remote sensing data source (optical or microwave), focusing on large-scale, flat areas and lacking comprehensive monitoring of small water bodies in complex terrain. Therefore, considering the complementary advantages of multisource remote sensing (multispectral and SAR), this paper proposes a multispectral and SAR fusion algorithm, named Multispectral and SAR Fusion algorithm (MASF), to better capture the remote sensing characteristics of small water bodies in complex areas. Based on this, a dataset containing spectral, texture, and geometric features is constructed, and multi-scale segmentation and random forest algorithms are applied for identification of small water bodies in complex terrain. The results demonstrate that the proposed fusion algorithm MASF exhibits minimal spectral distortion (SAM < 3.5, ERGAS <21, RMSE <0.01) and robust spatial feature enhancement (PSNR >40, SSIM >0.999, CC > 0.99). The Overall Accuracy (OA) and Kappa coefficients for both experimental areas surpassed 0.9. For rivers and reservoirs, both Producer's Accuracy (PA) and User's Accuracy (UA) exceeded 0.9. The UA for agricultural ponds exceeded 0.8. Comparative analysis with three other types of water-related data products shows that the freshwater identification results in this study have certain advantages in local small water bodies. Our research holds significant implications for the utilization of water resources in mountainous areas, prevention and control of floods and floods, as well as the development of aquaculture industry.
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The developmental choice made by temperate phages, between cell death (lysis) and viral dormancy (lysogeny), is influenced by the relative abundance of viruses and hosts in the environment. The paradigm for this abundance-driven decision is phage lambda of E. coli, whose propensity to lysogenize increases with the number of viruses coinfecting the same bacterium. It is believed that lambda uses this number to infer whether phages or bacteria outnumber each other. However, this interpretation is premised on an accurate mapping between the extracellular phage-to-bacteria ratio and the intracellular multiplicity of infection (MOI). Here, we show this premise to be faulty. By simultaneously labeling phage capsids and genomes, we find that, while the number of phages landing on each cell reliably samples the population ratio, the number of phages entering the cell does not. Single-cell infections, performed in a microfluidic device and interpreted using a stochastic model, reveal that the probability and rate of phage entry decrease with the number of adsorbed phages. This decrease reflects an MOI-dependent perturbation to host physiology caused by phage attachment, as evidenced by compromised membrane integrity and loss of membrane potential. The dependence of entry dynamics on the surrounding medium results in a strong impact on the infection outcome, while the protracted entry of coinfecting phages increases the heterogeneity in infection outcome at a given MOI. Our findings in lambda, and similar results we obtained for phages T5 and P1, demonstrate the previously unappreciated role played by entry dynamics in determining the outcome of bacteriophage infection.
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Bacteriófago lambda , Escherichia coli , Escherichia coli/virología , Escherichia coli/fisiología , Bacteriófago lambda/fisiología , Bacteriófago lambda/genética , Lisogenia , Internalización del VirusRESUMEN
Optical detection of magnetic field is appealing for integrated photonics; however, the light-matter interaction is usually weak at low field. Here we observe that the photoluminescence (PL) decreases by > 40% at 10 mT in rubrene microcrystals (RMCs) prepared by a capillary-bridge assembly method. The giant magneto-PL (MPL) relies on the singlet-triplet conversion involving triplet-triplet pairs, through the processes of singlet fission (SF) and triplet fusion (TF) during radiative decay. Importantly, the size of RMCs is critical for maximizing MPL as it influences on the photophysical processes of spin state conversion. The SF/TF process is quantified by measuring the prompt/delayed PL with time-resolved spectroscopies, which shows that the geminate SF/TF associated with triplet-triplet pairs are responsible for the giant MPL. Furthermore, the RMC-based magnetometer is constructed on an optical chip, which takes advantages of remarkable low-field sensitivity over a broad range of frequencies, representing a prototype of emerging opto-spintronic molecular devices.
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Single crystals of U2Mn3Ge and U2Fe3Ge with a Kagome lattice structure were synthesized using a high-temperature self-flux crystal growth method. The physical properties of these crystals were characterized through measurements of resistivity, magnetism, and specific heat. U2Fe3Ge exhibits ferromagnetic ground state and anomalous Hall effect, and U2Mn3Ge demonstrates a complex magnetic structure. Both compounds exhibit large Sommerfeld coefficient, indicating coexistence of heavy Fermion behaviour with magnetism. Our results suggest that this U2TM3Ge (TM = Mn, Fe, Co) family is a promising platform to investigate the interplay of magnetism, Kondo physics and the Kagome lattice.
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The process of labeling medical text plays a crucial role in medical research. Nonetheless, creating accurately labeled medical texts of high quality is often a time-consuming task that requires specialized domain knowledge. Traditional methods for generating labeled data typically rely on rigid rule-based approaches, which may not adapt well to new tasks. While recent machine learning (ML) methodologies have mitigated the manual labeling efforts, configuring models to align with specific research requirements can be challenging for labelers without technical expertise. Moreover, automated labeling techniques, such as transfer learning, face difficulties in in directly incorporating expert input, whereas semi-automated methods, like data programming, allow knowledge integration through rules or knowledge bases but may lack continuous result refinement throughout the entire labeling process. In this study, we present a collaborative human-ML teaming workflow that seamlessly integrates visual cluster analysis and active learning to assist domain experts in labeling medical text with high efficiency. Additionally, we introduce an innovative neural network model called the embedding network, which incorporates expert insights to generate task-specific embeddings for medical texts. We integrate the workflow and embedding network into a visual analytics tool named KMTLabeler, equipped with coordinated multi-level views and interactions. Two illustrative case studies, along with a controlled user study, provide substantial evidence of the effectiveness of KMTLabeler in creating an efficient labeling environment for medical text classification.
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The ionic toxicity induced by salinization has adverse effects on the growth and development of crops. However, researches on ionic toxicity and salt tolerance in plants have focused primarily on cations such as sodium ions (Na+), with very limited studies on chloride ions (Cl-). Here, we cloned the homologous genes of Arabidopsis thaliana AtCLCc, GhCLCc-1A/D, from upland cotton (Gossypium hirsutum), which were significantly induced by NaCl or KCl treatments. Subcellular localization showed that GhCLCc-1A/D were both localized to the tonoplast. Complementation of Arabidopsis atclcc mutant with GhCLCc-1 rescued its salt-sensitive phenotype. In addition, the silencing of the GhCLCc-1 gene led to an increased accumulation of Cl- in the roots, stems, and leaves of cotton seedlings under salt treatments, resulting in compromised salt tolerance. And ectopic expression of the GhCLCc-1 gene in Arabidopsis reduced the accumulation of Cl- in transgenic lines under salt treatments, thereby enhancing salt tolerance. These findings elucidate that GhCLCc-1 positively regulates salt tolerance by modulating Cl- accumulation and could be a potential target gene for improving salt tolerance in plants.
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Canales de Cloruro , Gossypium , Proteínas de Plantas , Tolerancia a la Sal , Arabidopsis/genética , Arabidopsis/metabolismo , Canales de Cloruro/genética , Canales de Cloruro/metabolismo , Cloruros/metabolismo , Regulación de la Expresión Génica de las Plantas , Gossypium/genética , Gossypium/metabolismo , Gossypium/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Tolerancia a la Sal/genética , Cloruro de Sodio/metabolismoRESUMEN
Surface water nutrient pollution, the primary cause of eutrophication, remains a major environmental concern in Western Lake Erie despite intergovernmental efforts to regulate nutrient sources. The Maumee River Basin has been the largest nutrient contributor. The two primary nutrient sources are inorganic fertilizer and livestock manure applied to croplands, which are later carried to the streams via runoff and soil erosion. Prior studies of nutrient source attribution have focused on large watersheds or counties at annual time scales. Source attribution at finer spatiotemporal scales, which enables more effective nutrient management, remains a substantial challenge. This study aims to address this challenge by developing a generalizable Bayesian network model for phosphorus source attribution at the subwatershed scale (12-digit Hydrologic Unit Code). Since phosphorus release is uncertain, we combine excess phosphorus derived from manure and fertilizer application and crop uptake data, flow information simulated by the SWAT model, and in-stream water quality measurements using Approximate Bayesian Computation to derive a posterior that attributes phosphorus contributions to subwatersheds. Our results show significant variability in subwatershed-scale phosphorus release that is lost in coarse-scale attribution. Phosphorus contributions attributed to the subwatersheds are on average lower than the excess phosphorus estimated by the nutrient balance approach currently adopted by environmental agencies. Fertilizer contributes more soluble reactive phosphorus than manure, while manure contributes most of the unreactive phosphorus. While developed for the specific context of Maumee River Basin, our lightweight and generalizable model framework could be adapted to other regions and pollutants and could help inform targeted environmental regulation and enforcement.
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Teorema de Bayes , Fertilizantes , Fósforo , Ríos , Calidad del Agua , Fósforo/análisis , Ríos/química , Fertilizantes/análisis , Monitoreo del Ambiente , Estiércol/análisisRESUMEN
Clostridium perfringens has emerged as a growing public health concern due to its ability to cause various infections and its increasing resistance to antibiotics. To assess its current epidemiology in clinical settings, we conducted a survey involving 426 healthy individuals and 273 ICU inpatients at a provincial hospital in China. Our findings revealed a high prevalence of C. perfringens in healthy individuals (45.77%, 95% CI: 41.0%-50.6%) and ICU patients (12.82%, 95% CI: 9.1%-17.4%). The identified 220 C. perfringens isolates displayed substantial resistance to erythromycin (57.9%), clindamycin (50.7%), and tetracycline (32.0%), primarily attributed to the presence of erm(Q) (54.4%), lnu(P) (13.8%), tetB(P) (83.6%), and tetA(P) (66.7%). Notably, C. perfringens isolates from this particular hospital demonstrated a high degree of sequence type diversity and phylogenic variation, suggesting that the potential risk of infection primarily arises from the bacteria's gut colonization rather than clonal transmissions within the clinical environment. This study provides an updated analysis of the current epidemiology of C. perfringens in healthy individuals and ICU patients in China and emphasizes the need to optimize intervention strategies against its public health threat. IMPORTANCE: Clostridium perfringens is a bacterium of growing public health concern due to its ability to cause infections and its increasing resistance to antibiotics. Understanding its epidemiology in clinical settings is essential for intervention strategies. This study surveyed healthy individuals and ICU inpatients in a provincial hospital in China. It found a high prevalence of C. perfringens, indicating infection risk. The isolates also showed significant antibiotic resistance. Importantly, the study revealed diverse sequence types and phylogenetic variation, suggesting infection risk from intestinal colonization rather than clonal transmission in hospitals. This analysis emphasizes the need to optimize intervention strategies against this public health threat.
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Antibacterianos , Portador Sano , Infecciones por Clostridium , Clostridium perfringens , Unidades de Cuidados Intensivos , Humanos , Clostridium perfringens/genética , Clostridium perfringens/aislamiento & purificación , Clostridium perfringens/efectos de los fármacos , Clostridium perfringens/clasificación , China/epidemiología , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/microbiología , Infecciones por Clostridium/transmisión , Masculino , Femenino , Persona de Mediana Edad , Adulto , Antibacterianos/farmacología , Portador Sano/microbiología , Portador Sano/epidemiología , Anciano , Prevalencia , Adulto Joven , Filogenia , Intestinos/microbiología , Pruebas de Sensibilidad Microbiana , Adolescente , Farmacorresistencia BacterianaRESUMEN
The dual emission (DE) characteristics of atomically precise copper nanoclusters (Cu NCs) are of significant theoretical and practical interest. Despite this, the underlying mechanism driving DE in Cu NCs remains elusive, primarily due to the complexities of excited state processes. Herein, a novel [Cu4(PPh3)4(C≡C-p-NH2C6H4)3]PF6 (Cu4) NC, shielded by alkynyl and exhibiting DE, was synthesized. Hydrostatic pressure was applied to Cu4, for the first time, to investigate the mechanism of DE. With increasing pressure, the higher-energy emission peak of Cu4 gradually disappeared, leaving the lower-energy emission peak as the dominant emission. Additionally, the Cu4 crystal exhibited notable piezochromism transitioning from cyan to orange. Angle-dispersive synchrotron X-ray diffraction results revealed that the reduced inter-cluster distances under pressure brought the peripheral ligands closer, leading to the formation of new C-Hâ â â N and N-Hâ â â N hydrogen bonds in Cu4. It is proposed that these strengthened hydrogen bond interactions limit the ligands' vibration, resulting in the vanishing of the higher-energy peak. In situ high-pressure Raman and vibrationally resolved emission spectra demonstrated that the benzene ring C=C stretching vibration is the structural source of the DE in Cu4.