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Monoculture is widely practiced to increase crop productivity, but long-term adaptation has drawbacks as it increases the depletion of soil nutrients and reduces soil quality, especially in dryland areas. Conversion from traditional maize monoculture to intercropping improves sustainable production. However, maize/peanut intercropping, especially rotation of planting strips impacts of maize/peanut intercropping in dryland on carbon (C) budgets and economic benefits remain unclear. In this study, a 5-year field experiment was conducted to evaluate the influence of maize/peanut intercropping with rotation of planting strips on soil health, indirect CO2-eq greenhouse gas emissions, and ecosystem C inputs. Four intercropping treatments viz. maize monoculture, peanut monoculture, maize/peanut intercropping, and maize/peanut rotation-intercropping were tested from 2018 to 2022. Maize/peanut rotation intercropping significantly improved the land equivalent ratio followed by intercropping and monoculture. Rotation-intercropping also improved economic benefits over intercropping and monoculture which were mainly associated with increased peanut yield where the border rows contributed the maximum, followed by the middle rows. Moreover, rotation-intercropping significantly increased the soil organic C and nitrogen (N) content. Rotation-intercropping decreased indirect CO2-eq greenhouse gas emissions and ecosystem C inputs by 3.11% and 18.04%, whereas increased ecosystem C outputs and net ecosystem C budget by 10.38% and 29.14%, respectively, over the average of monoculture. On average for intercropping and monoculture, rotation-intercropping increased ecosystem C emission efficiency for economic benefits by 51.94% and 227.27% in 2021 and 2022, respectively, showing the highest C utilization efficiency than other treatments. In the long run, maize/peanut rotation-intercropping can be practiced in dryland agriculture to achieve sustainable agriculture goals.
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Ecosistema , Gases de Efecto Invernadero , Arachis , Zea mays , Dióxido de Carbono , Agricultura , Suelo , ChinaRESUMEN
BACKGROUND: Hull colour is an important morphological marker for selection in seed production of foxtail millet. However, the molecular mechanisms underlying hull colour variation remain unknown. RESULTS: An F7 recombinant inbred line (RIL) population containing 215 lines derived from Hongjiugu × Yugu18 was used to analyze inheritance and detect the quantitative trait loci (QTL) for four hull colour traits using major gene plus polygene mixed inheritance analysis and composite interval mapping (CIM) in four environments. Genetic analysis revealed that the hull colour L* value (HCL*) was controlled by two major genes plus additive polygenes, the hull colour a* value (HCa*) was controlled by three major genes, the hull colour b* value (HCb*) was controlled by two major genes plus polygenes, and the hull colour C* value (HCC*) was controlled by four major genes. A high-density genetic linkage map covering 1227.383 cM of the foxtail millet genome, with an average interval of 0.879 cM between adjacent bin markers, was constructed using 1420 bin markers. Based on the genetic linkage map and the phenotypic data, a total of 39 QTL were detected for these four hull colour traits across four environments, each explaining 1.50%-49.20% of the phenotypic variation. Of these, six environmentally stable major QTL were co-localized to regions on chromosomes 1 and 9, playing a major role in hull colour. There were 556 annotated genes within the two QTL regions. Based on the functions of homologous genes in Arabidopsis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) gene annotations, five genes were predicted as candidate genes for further studies. CONCLUSIONS: This is the first study to use an inheritance model and QTL mapping to determine the genetic mechanisms of hull colour trait in foxtail millet. We identified six major environmentally stable QTL and predicted five potential candidate genes to be associated with hull colour. These results advance the current understanding of the genetic mechanisms underlying hull colour traits in foxtail millet and provide additional resources for application in genomics-assisted breeding and potential isolation and functional characterization of the candidate genes.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Setaria (Planta) , Sitios de Carácter Cuantitativo , Mapeo Cromosómico/métodos , Setaria (Planta)/genética , Carcinoma Hepatocelular/genética , Color , Neoplasias Hepáticas/genética , Fitomejoramiento , Estudios de Asociación GenéticaRESUMEN
The application of graphene-based nanomaterials (GBNs) has attracted global attention in various fields, and understanding defense mechanisms against the phytotoxicity of GBNs is crucial for assessing their environmental risks and safe-by-design. However, the related information is lacking, especially for edible vegetable crops. In the present study, GBNs (0.25, 2.5, and 25 mg/kg plant fresh weight) were injected into the stems of pepper plants. The results showed that the plant defense was regulated by reducing the calcium content by 21.7-48.3%, intercellular CO2 concentration by 12.0-35.2%, transpiration rate by 8.7-40.2%, and stomatal conductance by 16.9-50.5%. The defense pathways of plants in response to stress were further verified by the downregulation of endocytosis and transmembrane transport proteins, leading to a decrease in the nanomaterial uptake. The phytohormone gibberellin and abscisic acid receptor PYL8 were upregulated, indicating the activation of defense systems. However, reduced graphene oxide and graphene oxide quantum dots trigger stronger oxidative stress (e.g., H2O2 and malondialdehyde) than graphene oxide in fruits due to the breakdown of antioxidant defense systems (e.g., cytochrome P450 86A22 and P450 77A1). Both nontargeted proteomics and metabolomics consistently demonstrated that the downregulation of carbohydrate and upregulation of amino acid metabolism were the main mechanisms underlying the phytotoxicity and defense mechanisms, respectively.
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Grafito , Nanoestructuras , Mecanismos de Defensa , Grafito/toxicidad , Peróxido de Hidrógeno , Estrés OxidativoRESUMEN
The characteristics of striations in cylindrical hollow cathode discharge were investigated experimentally. The spectra of striations were measured at a pressure of 20 Pa in a discharge of 1.3 mA, in which the main spectra are the emission spectrum lines of the N2 first positive band (B3pi(g)-->A3pi(u)) and second positive band system (C3pi(u)-->B3pi(g)). The spatial characteristics of vibrational temperature of N2 were calculated based on the theory of double molecular spectrum. It is shown that the emission intensity exhibits a periodic structure with an unequal magnitude, and the spectral intensity of bright striation is higher than that of dark striations. The vibrational temperature of bright striation is of the value of 3500-4400K, moreover the vibrational temperature in the bright regions decreases from the cathode to the anode. In addition, the characteristics of striations at 1.0 mA and 1.5 mA were obtained, and the influence of discharge current on the striations was investigated. It is shown that the vibrational temperature and the distance between two striations increase. Finally the reduced electric field was calculated, which is about 44 approximately 49 m(-1) x Pa(-1), moreover it decreases with the increase in discharge current. The results are very useful for understanding the mechanism of discharge striations and for improving the stability of hollow cathode discharge.
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The frequency, duration, and intensity of heat waves (HWs) within terrestrial ecosystems are increasing, posing potential risks to agricultural production. Cerium dioxide nanoparticles (CeO2 NPs) are garnering increasing attention in the field of agriculture because of their potential to enhance photosynthesis and improve stress tolerance. In the present study, CeO2 NPs decreased the grain yield, grain protein content, and amino acid content by 16.2, 23.9, and 10.4%, respectively, under HW conditions. Individually, neither the CeO2 NPs nor HWs alone negatively affected rice production or triggered stomatal closure. However, under HW conditions, CeO2 NPs decreased the stomatal conductance and net photosynthetic rate by 67.6 and 33.5%, respectively. Moreover, stomatal closure in the presence of HWs and CeO2 NPs triggered reactive oxygen species (ROS) accumulation (increased by 32.3-57.1%), resulting in chloroplast distortion and reduced photosystem II activity (decreased by 9.4-36.4%). Metabolic, transcriptomic, and quantitative real-time polymerase chain reaction (qRT-PCR) analyses revealed that, under HW conditions, CeO2 NPs activated a stomatal closure pathway mediated by abscisic acid (ABA) and ROS by regulating gene expression (PP2C, NCED4, HPCA1, and RBOHD were upregulated, while CYP707A and ALMT9 were downregulated) and metabolite levels (the content of γ-aminobutyric acid (GABA) increased while that of gallic acid decreased). These findings elucidate the mechanism underlying the yield and nutritional losses induced by stomatal closure in the presence of CeO2 NPs and HWs and thus highlight the potential threat posed by CeO2 NPs to rice production during HWs.
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Cerio , Calor , Nanopartículas , Oryza , Estomas de Plantas , Oryza/metabolismo , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Cerio/química , Cerio/farmacología , Estomas de Plantas/metabolismo , Estomas de Plantas/efectos de los fármacos , Nanopartículas/química , Especies Reactivas de Oxígeno/metabolismo , Fotosíntesis/efectos de los fármacosRESUMEN
Soil legacy effects from previous crops can significantly influence plant-soil interactions in crop rotations. However, the microbial mechanism underlying this effect in subsequent root-associated compartments remains unclear. We investigated the effects of planting patterns (four-year continuous maize [MM], three-year winter wheat and one-year maize rotation [WM], and three-year potato and one-year maize rotation [PM]) on the microbial composition and structure of root-associated compartments, the effect of distinct crops on subsequent microbial co-occurrence patterns, and the assembly mechanism by which the root-associated compartments (bulk soil, rhizosphere, and roots) in subsequent crops regulate the microbiome habitat. Compared with MM, the relative abundance of Acidobacteria in WM was 29.7 % lower, whereas that of Bacteroidota in PM was 37.9 % higher in all three compartments. The co-occurrence patterns of the microbial communities exhibited varied responses to different planting patterns. Indicator taxon analysis revealed less shared and specific species in the root bacterial and fungal networks. The planting pattern elicited specific responses from modules within bacterial and fungal co-occurrence networks in all three compartments. Moreover, the planting patterns and root-associated compartments collectively drove the assembly process of root-associated microorganisms. The neutral model showed that, compared with MM, the stochasticity of bacterial assembly decreased under WM and PM but increased for fungal assembly. WM and PM increased the relative effects of the homogenized dispersal of fungal assemblies in roots. We conclude that previous crops exhibit marked legacy effects in the root-associated microbiome. Therefore, soil heritage should not be ignored when discussing microbiome recruitment strategies and co-occurrence patterns in subsequent crops.
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Agricultura , Productos Agrícolas , Raíces de Plantas , Microbiología del Suelo , Raíces de Plantas/microbiología , Productos Agrícolas/crecimiento & desarrollo , Solanum tuberosum/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Agricultura/métodos , Acidobacteria , RizosferaRESUMEN
Oceans absorb most excess heat from anthropogenic activities, leading to ocean warming. Moreover, microplastic pollution from anthropogenic activities is serious in marine environments and is accessible to various organisms. However, the combined effects of environmentally realistic ocean warming and microplastic pollution (OW+MP) on dominant marine species phytoplankton and related biochemical cycles are unclear. We investigated the combined effects on the dominant genera of diatoms (Chaetoceros gracilis, C. gracilis) over 100 generations. As a biological adjustment strategy, the growth rates of C. gracilis were nonsignificantly changed by OW+MP, body size decreased, and the chlorophyll a (Chl a) content and photosynthetic efficiency significantly decreased by 32.5% and 10.86%, respectively. The OW+MP condition inhibited carbon and nitrogen assimilation and sequestration capacity and allocated carbon into flexible forms of carbohydrates instead of proteins. Furthermore, the decrease in Si:C and Si:N ratios affected carbon transport to both the mesopelagic layer and deep ocean. Integrated transcriptomics and metabolomics showed that OW+MP disturbed ribosome and nitrogen metabolism. Given the rising concurrence of warming and MP pollution, the changes in metabolism suggest that the covariation in carbon, nitrogen and silicon biochemical cycles and the hidden influence on biodiversity and food web changes in the ocean should be reconsidered.
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Carbono , Diatomeas , Carbono/análisis , Clorofila A , Microplásticos/metabolismo , Plásticos/metabolismo , Fitoplancton , Océanos y Mares , Nitrógeno/metabolismo , Ciclo del NitrógenoRESUMEN
Shading can limit photosynthesis and plant growth. Understanding how phosphorus (P) application mitigates the effects of shading stress on morphology and physiology of mung beans (Vigna radiata L.) is of great significance for the establishment of efficient planting structures and optimizing P-use management. The effects of various light environments (non-shading stress, S0; low light stress, S1; severe shading stress, S2) on the growth of two mung bean cultivars (Xilv1 and Yulv1) and the role of P application (0 kg ha-1, P0; 90 kg ha-1, P1; 150 kg ha-1, P2) in such responses were investigated in a field experiment. Our results demonstrated that shading decreased the dry matter accumulation of mung bean markedly by limiting photosynthesis capacity and disrupting agronomic traits. For the leaf areas of the two cultivars, chlorophyll a+b, the net photosynthetic and electron transport rates were increased by 16.8%, 20.0%, 15.5%, and 12.5% under P1 treatment, and by 32.4%, 40.3%, 16.3% and 12.8% under P2 treatment, respectively, when compared to those for the non-fertilized plants under shading stress. These responses resulted in increased light capture and weak light utilization. Moreover, the activities of superoxide dismutase and peroxidase were enhanced by 20.9% and 43.7%, respectively; malondialdehyde and superoxide anion contents were reduced by 18.6% and 14.1%, respectively, under P application. These findings suggest that P application moderately mitigates the damage caused by shading stress and enhances tolerance by regulating mung bean growth. In addition, Xilv1 was more sensitive to P under shading stress than Yulv1.
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Fabaceae , Vigna , Antioxidantes/metabolismo , Vigna/metabolismo , Clorofila A , Fabaceae/metabolismo , Fotosíntesis , Hojas de la Planta/metabolismo , FertilizaciónRESUMEN
Microplastic pollution and heat waves, as damaging aspects of human activities, have been found to affect crop production and nitrogen (N) cycling in agroecosystems. However, the impacts of the combination of heat waves and microplastics on crop production and quality have not been analyzed. We found that heat waves or microplastics alone had slight effects on rice physiological parameters and soil microbial communities. However, under heat wave conditions, the typical low-density polyethylene (LDPE) and polylactic acid (PLA) microplastics decreased the rice yields by 32.1% and 32.9%, decreased the grain protein level by 4.5% and 2.8%, and decreased the lysine level by 91.1% and 63.6%, respectively. In the presence of heat waves, microplastics increased the allocation and assimilation of N in roots and stems but decreased those in leaves, which resulted in a reduction in photosynthesis. In soil, the concurrence of microplastics and heat waves induced the leaching of microplastics, which resulted in decreased microbial N functionality and disturbed N metabolism. In summary, heat waves amplified the disturbance induced by microplastics on the agroecosystem N cycle and therefore exacerbated the decreases in rice yield and nutrients induced by microplastics, which indicates that the environmental and food risks of microplastics deserve to be reconsidered.
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Microplásticos , Oryza , Humanos , Microplásticos/toxicidad , Plásticos , Calor , Suelo , Ciclo del Nitrógeno , NitrógenoRESUMEN
Foxtail millet (Setaria italica L.) is an important cereal for managing future water scarcity and ensuring food security, due to its strong drought and salt stress resistance owing to its developed root system. However, the molecular responses of foxtail millet leaves to salt stress are largely unknown. In this study, seeds of 104 foxtail millet accessions were subjected to 0.17 mol·L-1 NaCl stress during germination, and various germination-related parameters were analyzed to derive 5 salt-sensitive accessions and 13 salt-tolerant accessions. Hong Gu 2000 and Pu Huang Yu were the most salt-tolerant and salt-sensitive accessions, respectively. To determine the mechanism of the salt stress response, transcriptomic differences between the control and salt-treated groups were investigated. We obtained 2019 and 736 differentially expressed genes under salt stress in the salt-sensitive and salt-tolerant accessions, respectively. The transcription factor families bHLH, WRKY, AP2/ERF, and MYB-MYC were found to play critical roles in foxtail millet's response to salt stress. Additionally, the down-regulation of ribosomal protein-related genes causes stunted growth in the salt-sensitive accessions. The salt-tolerant accession alleviates salt stress by increasing energy production. Our findings provide novel insights into the molecular mechanism of foxtail millet's response to salt stress.
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Improving cropping systems together with suitable agronomic management practices can maintain dry farming productivity and reduce water competition with low N inputs. The objective of the study was to determine the photosynthetic and yield responses of maize and peanut under six treatments: sole maize, sole peanut, maize-peanut intercropping, maize-peanut rotation-intercropping, 20% and 40% N reductions for maize in the maize-peanut rotation-intercropping. Maize-peanut intercropping had no land-use advantage. Intercropped peanut is limited in carboxylation rates and electron transport rate (ETR), leading to a decrease in hundred-grain weight (HGW) and an increase in blighted pods number per plant (NBP). Intercropped peanut adapts to light stress by decreasing light saturation point (Isat) and light compensation point (Icomp) and increasing the electron transport efficiency. Intercropped maize showed an increase in maximum photosynthetic rate (Pnmax) and Icomp due to a combination of improved intercellular CO2 concentration, carboxylation rates, PSII photochemical quantum efficiency, and ETR. Compare to maize-peanut intercropping, maize-peanut rotation-intercropping alleviated the continuous crop barriers of intercropped border row peanut by improving carboxylation rates, electron transport efficiency and decreasing Isat, thereby increasing its HGW and NBP. More importantly, the land equivalent ratio of maize-peanut rotation-intercropping in the second and third planting years were 1.05 and 1.07, respectively, showing obvious land use advantages. A 20% N reduction for maize in maize-peanut rotation-intercropping does not affect photosynthetic character and yield for intercropped crops. However, a 40% N reduction decreased significantly the carboxylation rates, ETR, Icomp and Pnmax of intercropped maize, thereby reducing in a 14.83% HGW and 5.75% lower grain number per spike, and making land-use efficiency negative.
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Transparency and absorption overlaping with Mollow profile in a lambda three-level scheme driven by two coupling fields was investigated. There are two degenerate hyperfine levels within ground state. A strong coupling field and a probing field interact with the same optical transition between the excited state level and the first ground state hyperfine level, and an additional weak coupling field interacts with the excited state level and the second ground state hyperfine level, which is named double coupling lambda three-level scheme. It can be seen that when the strong coupling field is off-resonant, there is the superposition of Mollow profile with EIT, EIA and other quantum coherent phenomena, namely, Mollow profile with seven peaks. The dependence of the position of the EIT or EIA on Rabi frequency and frequency detuning of the strong coupling field was investigated. The results can be accounted for by dressed-state formalism.
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Understanding the bionanoscale recognition of nanostructured architectures is critical to the design and application of nanomaterials, but the related information is not well understood. In this study, it is found that bionanoscale recognition underlies cell fate and therapy. For example, 1T phase (octahedral coordination) monolayer MoS2 exhibits a markedly stronger affinity for fibronectin than the 2H structure (triangular prism coordination) and promotes cell spreading and differentiation. The van der Waals energy and increased turn components contribute to the high adhesion of fibronectin onto the 1T-MoS2 structure. 1T-MoS2 exhibits a significantly stronger affinity (KD , 6.59 × 10-7 m) for liposomes than 2H-MoS2 (1.21 × 10-6 m) due to strong hydrophobic interactions. The existence of octahedrally coordinated atomic structures that improve cell viability by enhancing the neurite length is first proven by random forest and structural equation models. Consequently, octahedral coordination disaggregates α-synuclein (e.g., by decreasing ß-sheets and increasing coil structures) and protects cells and hosts against Parkinson's disease. As a proof-of-principle demonstration, these findings indicate that bionanoscale recognition underlies the design of biomaterials and cell therapeutics.
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Nanoestructuras , Diferenciación Celular , Modelos TeóricosRESUMEN
Salty soil is a global problem that has adverse effects on plants. We demonstrate that bioself-assembled molybdenum-sulfur (Mo-S) crystals formed by the foliar application of MoCl5 and cysteine augment the photosynthesis of plants treated with 200 mM salt for 7 days by promoting Ca2+ signal transduction and free radical scavenging. Reductions in glutathione and phytochelatins were attributed to the biosynthesized Mo-S crystals. Plants embedded with the Mo-S crystals and exposed to salty soil exhibited carbon assimilation rates, photosynthesis rates (Fv/Fm), and electron transport rates (ETRs) that were increased by 40%, 63-173%, and 50-78%, respectively, compared with those of plants without Mo-S crystals. Increased compatible osmolyte levels and decreased levels of oxidative damage, stomatal conductance (0.63-0.42 mmol m2 s-1), and transpiration (22.9-15.3 mmol m2 s-1), free radical scavenging, and calcium-dependent protein kinase, and Ca2+ signaling pathway activation were evidenced by transcriptomics and metabolomics. The bioself-assembled crystals originating from ions provide a method for protecting plant development under adverse conditions.
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Fotosíntesis , Estrés Salino , Transporte de Electrón , Glutatión/metabolismo , Hojas de la Planta/metabolismo , Plantas/metabolismoRESUMEN
Many engineered nanomaterials (ENMs) and drugs have been fabricated to improve memory and promote neuroprotection, but their use remains challenging due to their high cost, poor ability to penetrate the blood-brain barrier (BBB), and many side effects. Herein, we found that nanoparticles with multiple enzymatic activities purified from groundwater (NMEGs) can efficiently cross the BBB and present memory-enhancing and neuroprotective effects in vitro and in vivo. In contrast to the adverse effects of chemicals and ENMs, NMEGs are able to cross the BBB by endocytosis without damaging the BBB and even possibly promote BBB integrity. NMEGs-treated normal mice were smarter and better behaved than saline-treated normal mice in the open-field test and Morris water maze test. NMEGs can enhance synaptic transmission by increasing neurotransmitter production and activating nicotinic acetylcholine receptors (nAChRs), activate the antioxidant enzyme system, and increase the number of mitochondria and ribosomes in cells. Intravenous NMEGs injection also rescued memory deficits and increased antioxidant capacity in Parkinson's disease (PD) mice due to the antioxidant activity caused by the presence of conjugated double bonds and abundant phenolic -OH groups. This study is a proof-of-principle demonstration that natural products are less expensive, more easily available, safer, and more effective ways to improve memory and promote neuroprotection than ENMs and reported drugs. Our article also shows the potential of NMEGs as a PD treatment in patients via intravenous injection, as they avoid the complex modifications of ENMs. In the future, it will be possible to treat PD by intravenously injecting NMEGs in patients.
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Agua Subterránea , Nanopartículas , Enfermedad de Parkinson , Animales , Antioxidantes/farmacología , Barrera Hematoencefálica , Humanos , Ratones , Nanopartículas/química , NeuroprotecciónRESUMEN
Biofilms contribute to bacterial infection and drug resistance and are a serious threat to global human health. Antibacterial nanomaterials have attracted considerable attention, but the inhibition of biofilms remains a major challenge. Herein, we propose a nanohole-boosted electron transport (NBET) antibiofilm concept. Unlike known antibacterial mechanisms (e.g., reactive oxygen species production and cell membrane damage), nanoholes with atomic vacancies and biofilms serve as electronic donors and receptors, respectively, and thus boost the high electron transport capacity between nanomaterials and biofilms. Electron transport effectively destroys the critical components (proteins, intercellularly adhered polysaccharides and extracellular DNA) of biofilms, and the nanoholes also significantly downregulate the expression of genes related to biofilm formation. The anti-infection capacity is thoroughly verified both in vitro (human cells) and in vivo (rat ocular and mouse intestinal infection models), and the nanohole-enabled nanomaterials are found to be highly biocompatible. Importantly, compared with typical antibiotics, nanomaterials are nonresistant and thereby exhibit high potential for use in various applications. As a proof-of-principle demonstration, these findings hold promise for the use of NBET in treatments for pathogenic bacterial infection and antibiotic drug resistance.
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Antibacterianos/administración & dosificación , Biopelículas/efectos de los fármacos , Nanoestructuras/administración & dosificación , Staphylococcus aureus/efectos de los fármacos , Animales , Células CACO-2 , Transporte de Electrón/efectos de los fármacos , Humanos , Ratones Endogámicos ICR , Pruebas de Sensibilidad Microbiana , Ratas Sprague-Dawley , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiologíaRESUMEN
Graphene oxide (GO) that has many advanced properties, has been applied in various fields, such as water treatments and removal of contaminations. Hypochlorite is widely used in water treatments. However, the effects of hypochlorite on the transformations and risks of GO, and the toxicological responses remain largely unknown, especially under visible-light irradiation. The present work found that visible-light irradiation promoted the breakdown of sp2 structures of GO by hypochlorite, producing alkanes and arenes with short carbon skeletons. Compared to oxygen-containing radicals, chlorine-related radicals contributed to the breakdown of carbon atomic rings of GO. Compared to pristine GO, the transformed GO inhibited algal reproduction, reduced photosynthesis, and promoted oxidative stress and membrane permeability. Substantial plasmolysis and increased numbers of starch grains were observed in the exposure groups. Metabolomics analysis found that oxidative stress and increased membrane permeability linked to downregulated proline. The downregulated pathways of alanine, aspartate and glutamate metabolism were associated with the inhibition of algal reproduction. The downregulated pathways related to protein synthesis and the secondary metabolism explained the strong toxicity induced by GO with hypochlorite and visible-light irradiation. The above results provide insight into the safety assessment of GO.
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Grafito , Ácido Hipocloroso , Luz , Estrés Oxidativo , ÓxidosRESUMEN
The eco-environment in eastern part of Qinghai-Tibet plateau is a rather complicated complex. The plants species there are quite diverse. The plant resource from Polygonaceae family used in traditional Tibetan medicine is very rich according to preliminary investigation. There were 6 genera and 15 species. The flora and the medicine value of them were analyzed. And some suggestions about traditional Tibetan medicine plant resource exploitation and utilization were presented.
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Medicina Tradicional Tibetana/métodos , Polygonaceae , ChinaRESUMEN
Hydrothermal carbonization (HTC) was employed to produce hydrochar from bamboo (Phyllostachys heterocycla cv. pubescens) shoot shell (BS) at severity (combined temperature and time) of 4.83-7.69. The pyrolysis and thermodynamics properties of the hydrochars were fully investigated. The results showed that the hydrochar properties (solid yield, C content, H/C and O/C atomic ratios, pyrolysis yield, pyrolysis index, formation of enthalpy, exergy, LHV, and HHV) of BS were highly dependent on severity and could be expressed by dose-response functions. The rapid variations of the hydrochar properties appeared at severity of 5.93-6.59. The pyrolysis temperature interval for the maximum weight loss shifted from 300 to 400°C at hydrothermal severity less than 6.59 to 400-500°C at hydrothermal severity greater than 6.59. The hydrochar thermal stability increased greatly with the severity increasing. And the thermodynamic properties of hydrochar approached those of lignin model compounds as the hydrothermal severity was greater than 6.59.