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Single Atoms Catalysts (SACs) have emerged as a class of highly promising heterogeneous catalysts, where the traditional bottom-up synthesis approaches often encounter considerable challenges in relation to aggregation issues and poor stability. Consequently, achieving densely dispersed atomic species in a reliable and efficient manner remains a key focus in the field. Herein, we report a new facile electrochemical knock-down strategy for the formation of SACs, whereby the metal Zn clusters are transformed into single atoms. While a defect-rich substrate plays a pivotal role in capturing and stabilizing isolated Zn atoms, the feasibility of this novel strategy is demonstrated through a comprehensive investigation, combining experimental and theoretical studies. Furthermore, when studied in exploring for potential applications, the material prepared shows a remarkable improvement of 58.21% for the Li+ storage and delivers a capacity over 300 Wh kg-1 after 500 cycles upon the transformation of Zn clusters into single atoms.
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BACKGROUND: Plant growth-regulating factors (GRFs) and GRF-interacting factors (GIFs) interact with each other and collectively have important regulatory roles in plant growth, development, and stress responses. Therefore, it is of great significance to explore the systematic evolution of GRF and GIF gene families. However, our knowledge and understanding of the role of GRF and GIF genes during plant evolution has been fragmentary. RESULTS: In this study, a large number of genomic and transcriptomic datasets of algae, mosses, ferns, gymnosperms and angiosperms were used to systematically analyze the evolution of GRF and GIF genes during the evolution of plants. The results showed that GRF gene first appeared in the charophyte Klebsormidium nitens, whereas the GIF genes originated relatively early, and these two gene families were mainly expanded by segmental duplication events after plant terrestrialization. During the process of evolution, the protein sequences and functions of GRF and GIF family genes are relatively conservative. As cooperative partner, GRF and GIF genes contain the similar types of cis-acting elements in their promoter regions, which enables them to have similar transcriptional response patterns, and both show higher levels of expression in reproductive organs and tissues and organs with strong capacity for cell division. Based on protein-protein interaction analysis and verification, we found that the GRF-GIF protein partnership began to be established in pteridophytes and is highly conserved across different terrestrial plants. CONCLUSIONS: These results provide a foundation for further exploration of the molecular evolution and biological functions of GRF and GIF genes.
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Desarrollo de la Planta , Plantas , Evolución Molecular , Filogenia , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genéticaRESUMEN
BACKGROUND: Root system architecture (RSA) exhibits significant genetic variability and is closely associated with drought tolerance. However, the evaluation of drought-tolerant cotton cultivars based on RSA in the field conditions is still underexplored. RESULTS: So, this study conducted a comprehensive analysis of drought tolerance based on physiological and morphological traits (i.e., aboveground and RSA, and yield) within a rain-out shelter, with two water treatments: well-watered (75 ± 5% soil relative water content) and drought stress (50 ± 5% soil relative water content). The results showed that principal component analysis identified six principal components, including highlighting the importance of root traits and canopy parameters in influencing drought tolerance. Moreover, the systematic cluster analysis was used to classify 80 cultivars into 5 categories, including drought-tolerant cultivars, relatively drought-tolerant cultivars, intermediate cultivars, relatively drought-sensitive cultivars, and drought-sensitive cultivars. Further validation of the drought tolerance index showed that the yield drought tolerance index and biomass drought tolerance index of the drought-tolerant cultivars were 8.97 and 5.05 times higher than those of the drought-sensitive cultivars, respectively. CONCLUSIONS: The RSA of drought-tolerant cultivars was characterised by a significant increase in average length-all lateral roots, a significant decrease in average lateral root emergence angle and a moderate root/shoot ratio. In contrast, the drought-sensitive cultivars showed a significant decrease in average length-all lateral roots and a significant increase in both average lateral root emergence angle and root/shoot ratio. It is therefore more comprehensive and accurate to assess field crop drought tolerance by considering root performance.
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Sequías , Gossypium , Gossypium/genética , Fenotipo , Agua , SueloRESUMEN
The crystal structure and phase stability of a host lattice plays an important role in efficient upconversion phenomena. In stable hosts, lanthanides doping should not generally change the crystal structure of the host itself. But when phase of a system drastically changes after lanthanide doping resulting in multiple phases, accurate identification of upconverting phase remains a challenge. Herein, an attempt to synthesize lanthanide-doped NiMoO4 by microwave hydrothermal method produced MoO3/Yb2Mo4O15/NiMoO4 micro-nano composite upconversion phosphor. A combined approach of density functional theory (DFT) calculations and single-particle-level upconversion imaging has been employed to elucidate the phase stability of different phases and upconversion properties within the composite. Through single-particle-level imaging under 980 nm excitation, an unprecedented resolution in visualizing individual emitting and non-emitting regions within the composite has been achieved, thereby allowing to accurately assign the Yb2Mo4O15 as a sole upconversion emitting phase in the composite. Result of the DFT calculation further shows that the Yb2Mo4O15 phase is the most thermodynamically preferred over other lanthanide-doped phases in the composite. This comprehensive understanding not only advances the knowledge of upconversion emission from composite materials but also holds promise for tailoring optical properties of materials for various applications, including bioimaging, sensing, and photonics, where controlled light emission is crucial.
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PURPOSE: The unsatisfactory efficacy of PD-L1 antibodies in glioblastoma (GBM) is largely due to the temporal and spatial heterogeneity of PD-L1 expression. Molecular imaging can enhance understanding of the tumor immune microenvironment and guide immunotherapy. However, highly sensitive imaging agents capable of effectively visualizing PD-L1 heterogeneity are limited. This study introduces a novel PET tracer, offering improved imaging of PD-L1 heterogeneity in GBM xenografts, with a comparative analysis to [18F]AlF-NOTA-WL12. METHODS: [18F]AlF-NOTA-PCP2 was synthesized with high purity and its affinity for PD-L1 was characterized using surface plasmon resonance (SPR) and cell binding assays. Its specificity for PD-L1 was evaluated both in vitro using various cell lines and in vivo with GBM xenograft models in NOD/SCID mice. PET/CT imaging was conducted to evaluate the tracer's biodistribution, pharmacokinetics, and ability to quantify tumoral spatial heterogeneity of PD-L1 expression. A focused comparative analysis between [18F]AlF-NOTA-PCP2 and [18F]AlF-NOTA-WL12 was conducted, examining binding affinity, biodistribution, pharmacokinetics, and imaging effectiveness in GBM xenografts. Additionally, human radiation dosimetry estimates compared the safety profiles of both tracers. RESULTS: [18F]AlF-NOTA-PCP2 demonstrated high radiochemical purity (> 95%) and a strong affinity for PD-L1, comparable to [18F]AlF-NOTA-WL12. In vitro and in vivo studies confirmed its specificity for PD-L1, with increased uptake in PD-L1 expressing cells and tumors. Toxicological profiles indicated no significant abnormalities in serum biochemical indicators or major organ tissues. MicroPET/CT imaging showed [18F]AlF-NOTA-PCP2's effectiveness in visualizing PD-L1 expression levels and spatial heterogeneity in GBM xenografts. Comparative studies revealed [18F]AlF-NOTA-PCP2's improved pharmacokinetic properties, including higher tumor-to-blood ratios and lower nonspecific liver uptake, as well as reduced radiation exposure compared to [18F]AlF-NOTA-WL12. CONCLUSION: [18F]AlF-NOTA-PCP2 distinguishes itself as an exceptionally sensitive PET/CT tracer, adept at non-invasively and accurately quantifying PD-L1 expression and its spatial heterogeneity in tumors, especially in GBM. Its favorable pharmacokinetic properties, safety profile, and high affinity for PD-L1 highlight its potential for enhancing the precision of cancer immunotherapy and guiding individualized treatment strategies. While promising, its clinical translation, especially in brain imaging, necessitates further validation in clinical trials.
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PURPOSE: This prospective study aims to evaluate the value of [18F]AlF-NOTA-fibroblast activation protein inhibitor (FAPI)-04 positron emission tomography-computed tomography (PET/CT) in predicting molecular subtypes of breast cancer. METHODS: The study consecutively recruited patients suspected of having breast cancer from a single center who were prospectively enrolled from July 2023 to May 2024 and underwent [18F]AlF-NOTA-FAPI-04 PET/CT. This study compared the differences in tracer uptake among breast cancers with different adverse prognostic factors and molecular subtypes. The classification performance for each molecular subtype of breast cancer was assessed using a receiver operating characteristic (ROC) curve. RESULTS: Fifty-three participants (mean age, 51 ± 11 years; 52 females) were evaluated. Breast cancer lesions with adverse prognostic factors showed higher tracer uptake. The five different molecular subtypes exhibited varying levels of uptake. The luminal A and luminal B (HER2-negative) subtypes had relatively low uptake, while the luminal B (HER2-positive), HER2-positive, and triple-negative subtypes had relatively high uptake. ROC analysis identified the max standardized uptake value (SUVmax) as a significant classifier (AUC = 0.912, P = 0.0005) for the luminal A subtype, with 100% sensitivity and 83% specificity. For predicting the luminal B (HER2-negative) subtype, SUVmax had an AUC of 0.770 (P = 0.0015). SUVmax, with an AUC of 0.781 (P = 0.003), was used to identify the triple-negative subtype tumors, resulting in a sensitivity of 100% and specificity of 51%. Lastly, the ROC curve showed the cut-off 15.40 (AUC = 0.921, P < 0.0001) could classify luminal A & luminal B (HER2-negative), and luminal B (HER2-positive) & HER2-positive & triple-negative, yielding a sensitivity of 94% and specificity of 79%. CONCLUSION: The uptake of [18F]AlF-NOTA-FAPI-04 is significantly correlated with the molecular subtypes of breast cancer, and [18F]AlF-NOTA-FAPI-04 PET/CT is a potential tool for noninvasive identification of luminal A subtypes and guidance of FAP-targeted therapies.
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Immune checkpoint inhibitors (ICIs) are a powerful treatment modality for various types of cancer. The effectiveness of ICIs is intimately connected to the binding status of antibodies to receptors. However, validated means to accurately evaluate target specificity and predict antibody efficacy in vivo are lacking. A novel peptide-based probe called Al[18F]F-NOTA-PCP1 was developed and validated for its specificity to PD-L1 in A549, U87MG, GL261, and GL261-iPDL1 cell lines, as well as in xenograft models. Then the probe was used in PET/CT scans to determine the binding status of PD-L1 antibodies (atezolizumab, avelumab, and durvalumab) in U87MG xenograft model mice. Moreover, Al[18F]F-NOTA-PCP1 was used to evaluate the impact of different treatment times and doses. Al[18F]F-NOTA-PCP1 PET/CT can be used to evaluate the interaction between PD-L1 and antibodies to determine the effectiveness of immunotherapy. By quantifying target engagement, the probe has the potential to predict the efficacy of immunotherapy and optimize the dose and treatment schedules for PD-L1 immunotherapy. This imaging agent could be a valuable tool in guiding personalized treatment strategies and improving cancer patient outcomes.
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Compuestos Heterocíclicos con 1 Anillo , Neoplasias , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Animales , Ratones , Antígeno B7-H1/metabolismo , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , PéptidosRESUMEN
Transcription of the covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is subject to dual regulation by host factors and viral proteins. MicroRNAs (miRNAs) can regulate the expression of target genes at the post-transcriptional level. Systematic investigation of miRNA expression in HBV infection and the interaction between HBV and miRNAs may deepen our understanding of the transcription mechanisms of HBV cccDNA, thereby providing opportunities for intervention. miRNA sequencing and real-time quantitative PCR (qRT-PCR) were used to analyze miRNA expression after HBV infection of cultured cells. Clinical samples were analyzed for miRNAs and HBV transcription-related indicators, using qRT-PCR, enzyme-linked immunoassay (ELISA), and Western blot. miRNA mimics or inhibitors were used to study their effects on the HBV life cycle. The target genes of miR-3188 and their roles in HBV cccDNA transcription were also identified. The expression of 10 miRNAs, including miR-3188, which was significantly decreased after HBV infection, was measured in clinical samples from patients with chronic HBV infection. Overexpression of miR-3188 inhibited HBV transcription, whereas inhibition of miR-3188 expression promoted HBV transcription. Further investigation confirmed that miR-3188 inhibited HBV transcription by targeting Bcl-2. miR-3188 is a key miRNA that regulates HBV transcription by targeting the host protein Bcl-2. This observation provides insights into the regulation of cccDNA transcription and suggests new targets for anti-HBV treatment.
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Hepatitis B Crónica , Hepatitis B , MicroARNs , Humanos , ADN Circular/genética , ADN Viral/genética , ADN Viral/metabolismo , Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/genética , MicroARNs/genética , MicroARNs/metabolismo , Transcripción Viral , Replicación Viral/genéticaRESUMEN
CH4 serves as an important greenhouse gas, yet limited knowledge is available in global and regional CH4 cycling, particularly in widely distributed karst terrain. In this study, we investigated an upland in Puding Karst Ecosystem Research Station, and explored CH4 concentration and/or flux in atmosphere, soil and cave using a closed static chamber method and an eddy covariance system. Meanwhile, we monitored atmospheric temperature, precipitation, temperature and wind velocity in the cave entrance. The results demonstrated that atmospheric CH4 and actual soil CH4 fluxes in the source area of eddy covariance system were -0.19 ± 8.64 nmols-1m-2 and -0.16 nmols-1m-2 respectively. The CH4 concentrations in Shawan Cave exhibited 10 â¼ 100-fold lower than that of the external atmosphere. CH4 oxidation rate dominated by methane-oxidizing bacteria was 1.98 nmols-1m-2 in Shawan Cave when it combined with temperature difference between cave and external atmosphere. Therefore, CH4 sink in global karst subterranean spaces was estimated at 106.2 Tg CH4 yr-1. We supplemented an understanding of CH4 cycling paths and fluxes in karst terrain, as well as CH4 sinks in karst subterranean space. Further works require to establish a karst ecosystem observation network to conduct long-term integrated studies on CH4 fluxes regarding atmosphere, soils, plants and caves.
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Atmósfera , Cuevas , Metano , Suelo , Metano/análisis , Metano/metabolismo , Atmósfera/química , Suelo/química , Monitoreo del Ambiente/métodos , Microbiología del Suelo , Contaminantes Atmosféricos/análisisRESUMEN
Lung cancer is one of the most common and intractable malignancies. It is associated with low survival rates despite existing treatments, indicating that new and more effective therapies are urgently needed such as the chimeric antigen receptor-T (CAR-T) cell immunotherapy. The cell-surface glucose-regulated protein 78 (csGRP78) is expressed in various hematological malignancies and solid tumor cells including lung cancer in response to cancer-related endoplasmic reticulum stress, while GRP78 is restricted to inside the normal cells. Here, we detected the prominent expression of csGRP78 in both lung cancer cell lines, A549 and H1299, as well as cancer stemlike cells derived from A549 by immunofluorescence. Next, a csGRP78-targeted CAR was constructed, and the transduced CAR-T cells were tested for their potency to kill the two lung cancer cell lines and derived stemlike cells, which was correlated with specific interferon γ release in vitro. Finally, we found that csGRP78 CAR-T cells also efficiently killed both lung cancer cells and cancer stemlike cells, resulting into the elimination of tumor xenografts in vivo, neither with any evidence of relapse after 63 days of tumor clearance nor any detrimental impact on other body organs we examined. Our study reveals the capacity of csGRP78 as a therapeutic target and offers valuable insight into the development of csGRP78 CAR-T cells as potential therapy for lung cancer.
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Neoplasias Pulmonares , Receptores Quiméricos de Antígenos , Humanos , Neoplasias Pulmonares/terapia , Xenoinjertos , Chaperón BiP del Retículo Endoplásmico , Recurrencia Local de Neoplasia , Proteínas de la Membrana , Glucosa , Linfocitos TRESUMEN
Zinc-air batteries (ZABs) have attracted considerable attention for their high energy density, safety, low noise, and eco-friendliness. However, the capacity of mechanically rechargeable ZABs was limited by the cumbersome procedure for replacing the zinc anode, while electrically rechargeable ZABs suffer from issues including low depth of discharge, zinc dendrite and dead zinc formation, and sluggish oxygen evolution reaction, etc. To address these issues, we report a hybrid redox-mediated zinc-air fuel cell (HRM-ZAFC) utilizing 7,8-dihydroxyphenazine-2-sulfonic acid (DHPS) as the anolyte redox mediator, which shifts the zinc oxidation reaction from the electrode surface to a separate fuel tank. This approach decouples fuel feeding and electricity generation, providing greater operation flexibility and scalability for large-scale power generation applications. The DHPS-mediated ZAFC exhibited a superior peak power density of 0.51â W/cm2 and a continuous discharge capacity of 48.82â Ah with ZnO as the discharge product in the tank, highlighting its potential for power generation.
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Microorganisms are key players in the global biogeochemical sulfur cycle. Among them, some have garnered particular attention due to their electrical activity and ability to perform extracellular electron transfer. A growing body of research has highlighted their extensive phylogenetic and metabolic diversity, revealing their crucial roles in ecological processes. In this review, we delve into the electron transfer process between sulfate-reducing bacteria and anaerobic alkane-oxidizing archaea, which facilitates growth within syntrophic communities. Furthermore, we review the phenomenon of long-distance electron transfer and potential extracellular electron transfer in multicellular filamentous sulfur-oxidizing bacteria. These bacteria, with their vast application prospects and ecological significance, play a pivotal role in various ecological processes. Subsequently, we discuss the important role of the pili/cytochrome for electron transfer and presented cutting-edge approaches for exploring and studying electroactive microorganisms. This review provides a comprehensive overview of electroactive microorganisms participating in the biogeochemical sulfur cycle. By examining their electron transfer mechanisms, and the potential ecological and applied implications, we offer novel insights into microbial sulfur metabolism, thereby advancing applications in the development of sustainable bioelectronics materials and bioremediation technologies.
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The excellent comprehensive properties of microfiber synthetic leathers have led to their wide application in various aspects of our lives. However, the issue of flammability remains a significant challenge that needs to be addressed. Nowadays, the bio-based chemicals used in the flame-retardant materials have extremely grabbed our eyes. Herein, we developed an ecologically friendly flame-retardant microfiber synthetic leather using phosphorus-free layer-by-layer assembly technology (LBL) based on natural polysaccharide alginate (SA) coupled with polyethyleneimine (PEI) and 3-aminopropyltriethoxysilane (APTES). The effect of different LBL coating systems on the flame retardancy of microfiber synthetic leather was investigated. The results demonstrated that the introduction of APTES can completely inhibit the melt-dripping by enhancing char formation through silica elements. Furthermore, the trinary coating system consisting of SA/APTES/PEI exhibited excellent flame retardancy by combining gas-phase action from PEI and condensed-phase function from APTES. This modified microfiber synthetic leather showed a significantly higher limiting oxygen index (LOI) value of 33.0 % with no molten droplet. Additionally, the SA-based coating slightly suppressed the heat release, resulting in a 20 % reduction in total heat release during the combustion test. Overall, this work presents a facile and environmentally-friendly approach for achieving flame-retardant and anti-dripping microfiber synthetic leather.
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Alginatos , Retardadores de Llama , Propilaminas , Silanos , Epidermis , Ojo , Fósforo , PolietileneiminaRESUMEN
The abuse of doxycycline (DC) can lead to residues in animals and water environments, which severely threaten human health; however, currently accepted detection methods are generally complicated and cannot be used for real-time detection. Therefore, developing a method for rapid real-time detection of DC microcontent residues is highly important. Herein, based on the Mach-Zehnder interference, we propose a simple tapered droplet structure fiber sensor with a high detection sensitivity. By modifying the sensing region with a molecularly imprinted polymer film of DC, this sensor realizes the specific detection of DC and has a detection sensitivity of 58.81 pm/ppm for DC in a large concentration range of 0-300 ppm. This sensor can be used to detect DC microcontent in aqueous solutions in real time.
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BACKGROUND: Radiation therapy is one of the most common treatments for non-small cell lung cancer (NSCLC). However, the insensitivity of some tumor cells to radiation is one of the major reasons for the poor efficacy of radiotherapy and the poor prognosis of patients, and exploring the underlying mechanisms behind radioresistance is the key to solving this clinical challenge. This study aimed to identify the molecules associated with radioresistance in lung adenocarcinoma (LUAD), identified thyroid hormone receptor interactor 13 (TRIP13) as the main target initially, and explored whether TRIP13 is related to radioresistance in LUAD and the specific mechanism, with the aim of providing theoretical basis and potential targets for the combination therapy of LUAD patients receiving radiotherapy in the clinic. METHODS: Three datasets, GSE18842, GSE19188 and GSE33532, were selected from the Gene Expression Omnibus (GEO) database and screened for differentially expressed genes (|log FC|>1.5, P<0.05) in each of the three datasets using the R 4.1.3 software, and then Venn diagram was used to find out the differentially expressed genes common to the three datasets. The screened differential genes were then subjected to protein-protein interaction (PPI) analysis and module analysis with the help of STRING online tool and Cytoscape software, and survival prognosis analysis was performed for each gene with the help of Kaplan-Meier Plotter database, and the TRIP13 gene was identified as the main molecule for subsequent studies. Subsequently, the human LUAD cell line H292 was irradiated with multiple X-rays using a sub-lethal dose irradiation method to construct a radioresistant cell line, H292DR. The radioresistance of H292DR cells was verified using cell counting kit-8 (CCK-8) assay and clone formation assay. The expression levels of TRIP13 in H292 and H292DR cells were measured by Western blot. Small interfering RNA (siRNA) was used to silence the expression of TRIP13 in H292DR cells and Western blot assay was performed. The clone formation ability and migration ability of H292DR cells were observed after TRIP13 silencing, followed by the detection of changes in the expression levels of proteins closely related to homologous recombination, such as ataxia telangiectasia mutated (ATM) protein. RESULTS: Screening of multiple GEO datasets, validation of external datasets and survival analysis revealed that TRIP13 was highly expressed in LUAD and was associated with poor prognosis in LUAD patients who had received radiation therapy. And the results of gene set enrichment analysis (GSEA) of TRIP13 suggested that TRIP13 might be closely associated with LUAD radioresistance by promoting homologous recombination repair after radiation therapy. Experimentally, TRIP13 expression was found to be upregulated in H292DR, and silencing of TRIP13 was able to increase the sensitivity of H292DR cells to radiation. CONCLUSIONS: TRIP13 is associated with poor prognosis in LUAD patients treated with radiation, possibly by promoting a homologous recombination repair pathway to mediate resistance of LUAD cells to radiation.
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Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/radioterapia , Recuento de Células , Terapia Combinada , ATPasas Asociadas con Actividades Celulares Diversas , Proteínas de Ciclo CelularRESUMEN
BiOCl materials have received much attention because of their unique optical and electrical properties. Still, their unsatisfactory catalytic performance has been troubling researchers, limiting the application of BiOCl-based photocatalysts. Therefore, many researchers have studied the adjustment of BiOCl-based materials to enhance photocatalytic efficiency. This review focuses on surface and interface engineering strategies for boosting the photocatalytic performance of BiOCl-based nanomaterials, including forming oxygen vacancy defects, constructing metal/BiOCl, and the fabrication of semiconductor/BiOCl nanocomposites. The photocatalytic applications of the above composites are also concluded in photodegradation of aqueous pollutants, photocatalytic NO removal, photo-induced H2 production, and CO2 reduction. Special emphasis has been given to the modification methods of BiOCl and photocatalytic mechanisms to provide a more detailed understanding for researchers in the fields of energy conversion and materials sciences.
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Fine-grained image retrieval mainly focuses on learning salient features from the seen subcategories as discriminative embedding while neglecting the problems behind zero-shot settings. We argue that retrieving fine-grained objects from unseen subcategories may rely on more diverse clues, which are easily restrained by the salient features learnt from seen subcategories. To address this issue, we propose a novel Content-aware Rectified Activation model, which enables this model to suppress the activation on salient regions while preserving their discrimination, and spread activation to adjacent non-salient regions, thus mining more diverse discriminative features for retrieving unseen subcategories. Specifically, we construct a content-aware rectified prototype (CARP) by perceiving semantics of salient regions. CARP acts as a channel-wise non-destructive activation upper bound and can be selectively used to suppress salient regions for obtaining the rectified features. Moreover, two regularizations are proposed: 1) a semantic coherency constraint that imposes a restriction on semantic coherency of CARP and salient regions, aiming at propagating the discriminative ability of salient regions to CARP, 2) a feature-navigated constraint to further guide the model to adaptively balance the discrimination power of rectified features and the suppression power of salient features. Experimental results on fine-grained and product retrieval benchmarks demonstrate that our method consistently outperforms the state-of-the-art methods.
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Emergence and spread of antibiotic resistance genes (ARGs) in lakes have been considered as a global health threat. However, a thorough understanding of the distribution patterns and ecological processes that shape the ARGs profile in interconnected river-lake systems remains largely unexplored. In this study, we collected paired water and sediment samples from a typical interconnected river-lake system, Dongting Lake in China, during both wet and dry seasons. Using high-throughput quantitative PCR, we investigated the spatial and temporal distribution of ARGs and the factors that influence them. A total of 8 major antibiotic classes and 10 mobile genetic elements were detected across the Dongting Lake basin. The unique hydrological characteristics of this interconnected river-lake system result in a relatively stable abundance of ARGs across different seasons and interfaces. During the wet season, deterministic processes dominated the assembly of ARGs, allowing environmental factors, such as heavy metals, to serve as main driving forces of ARGs distribution. When the dry season arrived, variations in hydrological conditions and changes in ARGs sources caused stochastic processes to dominate the assembly of ARGs. Our findings provide valuable insights for understanding the ecological processes of ARGs in interconnected river-lake systems, emphasizing the necessity of upstream restoration and clarifying river-lake relationships to mitigate ARGs dissemination.
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Farmacorresistencia Microbiana , Monitoreo del Ambiente , Lagos , Ríos , China , Farmacorresistencia Microbiana/genética , Estaciones del Año , Genes Bacterianos , AntibacterianosRESUMEN
Phenyllactic acid (PLA) as a natural phenolic acid exhibits antibacterial activity against non-spore-forming bacteria, while the inhibitory effect against bacterial spore remained unknown. Herein, this study investigated the inactivation effect of PLA against Bacillus cereus spores. The results revealed that the minimum inhibitory concentration of PLA was 1.25 mg/mL. PLA inhibited the outgrowth of germinated spores into vegetative cells rather than germination of spores. PLA disrupted the spore coat, and damaged the permeability and integrity of inner membrane. Moreover, PLA disturbed the establishment of membrane potential due to the inhibition of oxidative metabolism. SEM observations further visualized the morphological changes and structural disruption caused by PLA. Besides, PLA caused the degradation of DNA of germinated spores. Finally, PLA was applied in milk beverage, and showed promising inhibitory effect against B. cereus spores. This finding could provide scientific basis for the application of PLA against spore-forming bacteria in food industry.