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The objectives of this study were to measure the chlorophyll fluorescence (ChlF) parameters of Barbula indica (Hook.) Spreng and Conocephalum conicum (L.) Dumort subjected to various light intensities (LI) as a reflection of their adaptability to their habitats. The electron transport rate (ETR) of all plants under 500 µmol m-2 s-1 photosynthetic photon flux density (PPFD) was significantly higher than other LI treatments, implying that these plants could be grown under a specific and optimal light intensity adapted to 500 PPFD conditions. As LI increased from 50 to 2,000 PPFD, we observed in all plants increased non-photochemical quenching (NPQ) and photo-inhibitory quenching (qI) and decreased photosystem II efficiency (ΦPSII), potential quantum efficiency of PSII (Fv/Fm), actual PSII efficiency (ΔF/Fm'%), and Fv/Fm%. In addition, energy-dependent quenching (qE), the light protection system (qE + qZ + qT), and qI increased as ΦPSII decreased and photo-inhibition% increased under 1000, 1500, and 2000 PPFD conditions, suggesting that these plants had higher photo-protective ability under high LI treatments to maintain higher photosynthetic system performance. B. indica plants remained photochemically active and maintained higher qE under 300, 500, and 1000 PPFD, whereas C. conicum qZ + qT exhibited higher photo-protection under 500, 1000, and 1500 PPFD conditions. These ChlF indices can be used for predicting photosynthetic responses to light induction in different bryophytes and provide a theoretical basis for ecological monitoring.
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Clorofila , Hojas de la Planta , Clorofila/fisiología , Hojas de la Planta/fisiología , Fotosíntesis , Luz , Transporte de Electrón , Complejo de Proteína del Fotosistema II/metabolismoRESUMEN
Electrochemical gas-evolving reactions have been widely used for industrial energy conversion and storage processes. Gas bubbles form frequently at the electrode surface due to a small gas solubility, thereby reducing the effective reaction area and increasing the over-potential and ohmic resistance. However, the growth and motion mechanisms for tiny gas bubbles on the electrode remains elusive. Combining molecular dynamics (MD) and fluid dynamics simulations (CFD), we show that there exists a lateral solutal Marangoni force originating from an asymmetric distribution of dissolved gas near the bubble. Both MD and CFD simulations deliver a similar magnitude of the Marangoni force of â¼0.01 nN acting on the bubble. We demonstrate that this force may lead to lateral bubble oscillations and analyze the phenomenon of dynamic self-pinning of bubbles at the electrode boundary.
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As the physicochemical properties of ultrafine bubble systems are governed by their size, it is crucial to determine the size and distribution of such bubble systems. At present, the size or size distribution of nanometer-sized bubbles in suspension is often measured by either dynamic light scattering or the nanoparticle tracking analysis. Both techniques determine the bubble size via the Einstein-Stokes equation based on the theory of the Brownian motion. However, it is not yet clear to which extent the Einstein-Stokes equation is applicable for such ultrafine bubbles. In this work, using atomic molecular dynamics simulation, we evaluate the applicability of the Einstein-Stokes equation for gas nanobubbles with a diameter less than 10 nm, and for a comparative analysis, both vacuum nanobubbles and copper nanoparticles are also considered. The simulation results demonstrate that the diffusion coefficient for rigid nanoparticles in water is found to be highly consistent with the Einstein-Stokes equation, with slight deviation only found for nanoparticle with a radius less than 1 nm. For nanobubbles, including both methane and vacuum nanobubbles, however, large deviation from the Einstein-Stokes equation is found for the bubble radius larger than 3 nm. The deviation is attributed to the deformability of large nanobubbles that leads to a cushioning effect for collision-induced bubble diffusion.
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Plastic products' widespread applications and their non-biodegradable nature have resulted in the continuous accumulation of microplastic waste, emerging as a significant component of ecological environmental issues. In the field of microplastic detection, the intricate morphology poses challenges in achieving rapid visual characterization of microplastics. In this study, photoacoustic imaging technology is initially employed to capture high-resolution images of diverse microplastic samples. To address the limited dataset issue, an automated data processing pipeline is designed to obtain sample masks while effectively expanding the dataset size. Additionally, we propose Vqdp2, a generative deep learning model with multiple proxy tasks, for predicting six forms of microplastics data. By simultaneously constraining model parameters through two training modes, outstanding morphological category representations are achieved. The results demonstrate Vqdp2's excellent performance in classification accuracy and feature extraction by leveraging the advantages of multi-task training. This research is expected to be attractive for the detection classification and visual characterization of microplastics.
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Aprendizaje Profundo , Microplásticos , Técnicas Fotoacústicas , Microplásticos/análisis , Técnicas Fotoacústicas/métodos , Monitoreo del Ambiente/métodos , PlásticosRESUMEN
Speed judgment is a vital component of autonomous driving perception systems. Automobile drivers were able to evaluate their speed as a result of their driving experience. However, driverless automobiles cannot autonomously evaluate their speed suitability through external environmental factors such as the surrounding conditions and traffic flows. This study introduced the parameter of overtaking frequency (OTF) based on the state of the traffic flow on both sides of the lane to reflect the difference between the speed of a driverless automobile and its surrounding traffic to solve the above problem. In addition, a speed evaluation algorithm was proposed based on the long short-term memory (LSTM) model. To train the LSTM model, we extracted OTF as the first observation variable, and the characteristic parameters of the vehicle's longitudinal motion and the comparison parameters with the leading vehicle were used as the second observation variables. The algorithm judged the velocity using a hierarchical method. We conducted a road test by using real vehicles and the algorithms verified the data, which showed the accuracy rate of the model is 93%. As a result, OTF is introduced as one of the observed variables that can support the accuracy of the algorithm used to judge speed.
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Sweet potato (Ipomoea batatas) is one of the most important food crops worldwide and its leaves provide a dietary source of nutrients and various bioactive compounds. These constituents of sweet potato leaves (SPL) vary among varieties and play important roles in treating and preventing various diseases. Recently, more attentions in health-promoting benefits have led to several in vitro and in vivo investigations, as well as the identification and quantification of bioactive compounds in SPL. Among them, many new compounds have been reported as the first identified compounds from SPL with their dominant bioactivities. This review summarizes the current knowledge of the bioactive compositions of SPL and their health benefits. Since SPL serve as a potential source of micronutrients and functional compounds, they can be further developed as a sustainable crop for food and medicinal industries.
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Antioxidantes/química , Productos Agrícolas/química , Ipomoea batatas/química , Fitoquímicos/química , Hojas de la Planta/química , Antioxidantes/uso terapéutico , Fitoquímicos/uso terapéuticoRESUMEN
Long non-coding RNAs have been demonstrated to be important regulators of various cancers, though the precise mechanisms remain unclear. Although lincFOXF1 has been reported to act as a tumour suppressor, its function and underlying mechanisms in osteosarcoma have not yet been explored. We employed quantitative real-time polymerase chain reaction (qRT-PCR) to evaluate the expression of lincFOXF1 and GAPDH in osteosarcoma tissues and cell lines, and colony-formation, CCK8, wound-healing, and transwell assays were conducted to analyse the proliferation, migration, and invasion capacity of osteosarcoma cells. Subcellular localization analysis by fractionation and RNA immunoprecipitation assays were performed to elucidate the mechanism responsible for lincFOXF1-mediated phenotypes of osteosarcoma cells. The results revealed that lincFOXF1 expression is significantly decreased and strongly related to Enneking stage as well as metastasis in osteosarcoma patients. Further experiments showed that lincFOXF1 inhibits the migration, invasion and metastasis of cells in vitro and vivo. Mechanistic investigation demonstrated that lincFOXF1 physically binds to EZH2, a polycomb repressive complex 2 (PRC2) component, and a search for downstream targets suggested that G-protein-coupled receptor kinase-interacting protein 1 (GIT1) is involved in the lincFOXF1-mediated repression of osteosarcoma cells migration and invasion. Moreover, GIT1 expression is inversely correlated with lincFOXF1 in osteosarcoma. The present findings indicate that lincFOXF1 is involved in the progression of osteosarcoma through binding with EZH2, further regulating GIT1 expression. Our results suggest that lincFOXF1 may serve as a biomarker and therapeutic target for osteosarcoma patients.
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Movimiento Celular/genética , Progresión de la Enfermedad , Osteosarcoma/genética , Osteosarcoma/patología , ARN Largo no Codificante/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adulto , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Núcleo Celular/metabolismo , Proliferación Celular/genética , Regulación hacia Abajo/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Invasividad Neoplásica , Metástasis de la Neoplasia , Complejo Represivo Polycomb 2/metabolismo , Unión Proteica , ARN Largo no Codificante/genética , Adulto JovenRESUMEN
BACKGROUND: Most gastrointestinal stromal tumours (GIST) are driven by activating oncogenic mutations of KIT/PDGFRA, which provide a compelling therapeutic target. Our previous studies showed that CDC37, regulated by casein kinase 2 (CK2), is a crucial HSP90 cofactor for KIT oncogenic function and a promising and more selective therapeutic target in GIST. METHODS: Biologic mechanisms of CK2-mediated CDC37 regulation were assessed in GISTs by immunoblotting, immunoprecipitations, knockdown and inactivation assays. The effects of a combination of KIT and CK2 inhibition were assessed by immunoblotting, cell viability, colony growth, cell cycle analysis, apoptosis, migration and invasiveness. RESULTS: CK2 overexpression was demonstrated by immunoblotting in GIST cell lines and patient biopsies. Treatment with a specific CK2 inhibitor, CX4945, leads to CDC37 dephosphorylation and inhibits KIT signalling in imatinib-sensitive and in imatinib-resistant GIST cell lines. Immunoprecipitation demonstrated that CK2 inhibition blocks KIT:HSP90:CDC37 interaction in GIST cells. Coordinated inhibition of CK2 and KIT by CX4945 (or CK2 shRNA) and imatinib, respectively, leads to increased apoptosis, anti-proliferative effects and cell cycle arrest and decreased p-AKT and p-S6 expression, migration and invasiveness in all GIST cell lines compared with either intervention alone, indicating additive effects of inhibiting these two important regulators of GIST biology. CONCLUSION: Our findings suggest that combinatorial inhibition of CK2 and KIT warrants evaluation as a novel therapeutic strategy in GIST, especially in imatinib-resistant GIST.
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Quinasa de la Caseína II/genética , Proteínas de Ciclo Celular/metabolismo , Chaperoninas/metabolismo , Neoplasias Gastrointestinales/genética , Tumores del Estroma Gastrointestinal/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Proteínas Proto-Oncogénicas c-kit/genética , Apoptosis/efectos de los fármacos , Apoptosis/genética , Quinasa de la Caseína II/antagonistas & inhibidores , Quinasa de la Caseína II/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Neoplasias Gastrointestinales/metabolismo , Tumores del Estroma Gastrointestinal/metabolismo , Técnicas de Silenciamiento del Gen , Proteínas HSP90 de Choque Térmico/efectos de los fármacos , Humanos , Mesilato de Imatinib/farmacología , Naftiridinas/farmacología , Fenazinas , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-kit/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-kit/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Ionic liquids (ILs) are commonly known as "green" solvents and have been widely used in various fields. However, the ecotoxicity of ILs in aquatic environment has received considerable attention from scientific researchers. This study investigated the toxic effects of different concentrations of 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim][PF6]) (0, 1.35, 2.70 and 5.40 mg/L) on intestinal physical barrier, immunological barrier, and intestinal microbiome in common carp on days 30 and 60. The results showed that ([C8mim][PF6]) exposure could reduce the intestinal villus height, decrease the mRNA expression of tight junction genes (occludin, claudin-2 and zonula occludens-1), and increase the levels of D-lactic and diamine oxidase, and reduce acid phosphatase and lysozyme activities, complement 3 and 4 contents, and anti-inflammatory cytokine TGF-ß protein level, while increase pro-inflammatory cytokines TNF-α and IL-1ß protein levels in common carp. Moreover, ([C8mim][PF6]) exposure was also found to significantly reduce gut microbial diversity and alter microbial community structure in common carp. Collectively, our study highlighted that exposure to ([C8mim][PF6]) could disrupt intestinal physical barrier, impair immunological barrier and alter intestinal microbiome in common carp, suggesting that ILs exert a negative effect on fish intestinal health status and may pose serious health risks in fish. The results of this study may be helpful to illuminate the toxicity mechanisms of the ILs on fish.
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Carpas , Microbioma Gastrointestinal , Líquidos Iónicos , Animales , Citocinas/genética , Dieta , Proteínas de Peces , Mucosa Intestinal , Intestinos , Líquidos Iónicos/toxicidadRESUMEN
We present a novel approach for studying membrane formation by the interaction of polymers and surfactants with opposite charge using a Hele-Shaw experimental setup. A solution of the anionic biopolymer xanthan gum is placed in direct contact with a CnTAB surfactant solution (n = 10, 12, 14, and 16). Thereby, a polymer-surfactant membrane spontaneously forms between the two solutions due to the precipitation of polymer-surfactant complexes, which grows afterwards in the direction of the polymer solution. The dynamics of the growth of the membrane thickness and the mass transfer of polymer are evaluated for different surfactant types and concentrations. The experiments and supporting numerical calculations indicate that polymer mass transfer is driven by diffusion of the charged macromolecules along the concentration gradient, which is coupled to the electric field induced by the faster diffusion of the more mobile counterions. The properties and structure of the formed membrane significantly depend on the surfactant hydrophobicity and concentration. In addition, in a wide range of experiments, the formation of a porous structure in the membrane is observed whose characteristics can be tuned by the process parameters. A mechanism is proposed for the pore formation explaining it as an instability of the growing membrane surface in interaction with the supply of polymer across the depleted zone in the vicinity of the membrane front.
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Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.
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Ficus/genética , Fotosíntesis/genética , Proteínas de Plantas/genética , Transcriptoma/genética , Arabidopsis/genética , Hidrolasas de Éster Carboxílico/genética , Clorofila/genética , Cloroplastos/genética , Ficus/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Proteolisis , Tilacoides/genéticaRESUMEN
BACKGROUND: Leaf epicuticular wax is an important functional trait for physiological regulation and pathogen defense. This study tests how selective pressure may have forced the trait of leaf abaxial epicuticular wax crystals (LAEWC) and whether the presence/absence of LAEWC is associated with other ecophysiological traits. Scanning Electron Microscopy was conducted to check for LAEWC in different Lithocarpus species. Four wax biosynthesis related genes, including two wax backbone genes ECERIFERUM 1 (CER1) and CER3, one regulatory gene CER7 and one transport gene CER5, were cloned and sequenced. Ecophysiological measurements of secondary metabolites, photosynthesis, water usage efficiency, and nutrition indices were also determined. Evolutionary hypotheses of leaf wax character transition associated with the evolution of those ecophysiological traits as well as species evolution were tested by maximum likelihood. RESULTS: Eight of 14 studied Lithocarpus species have obvious LAEWC appearing with various types of trichomes. Measurements of ecophysiological traits show no direct correlations with the presence/absence of LAEWC. However, the content of phenolic acids is significantly associated with the gene evolution of the wax biosynthetic backbone gene CER1, which was detected to be positively selected when LAEWC was gained during the late-Miocene-to-Pliocene period. CONCLUSIONS: Changes of landmass and vegetation type accelerated the diversification of tropical and subtropical forest trees and certain herbivores during the late Miocene. As phenolic acids were long thought to be associated with defense against herbivories, co-occurrence of LAEWC and phenolic acids may suggest that LAEWC might be an adaptive defensive mechanism in Lithocarpus.
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Adaptación Biológica/fisiología , Fagaceae/fisiología , Hojas de la Planta/química , Proteínas de Plantas/genética , Ceras/química , Adaptación Biológica/genética , Evolución Molecular , Fagaceae/genética , Fagaceae/ultraestructura , Hidroxibenzoatos/metabolismo , Microscopía Electrónica de Rastreo , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Metabolismo Secundario , Selección GenéticaRESUMEN
A feeding experiment was conducted to investigate the effects of Rehmannia glutinosa (RG) on the bacterial, archaeal, and fungal community composition in the gut of common carp (Cyprinus carpio L.). Common carp were given a control diet and an RG-supplemented diet (basal diet plus 4% prepared Rehmannia root powder) over a period of 80 days. Our results indicated that the bacteria Fusobacteria, Proteobacteria, and Bacteroidetes; the archaea Crenarchaeota and Euryarchaeota; and the fungi Basidiomycota are the most abundant microbial taxa in the gut of common carp. Compared with the common carp fed a control diet, the common carp fed an RG-supplemented diet contained a higher content of Akkermansia sp., and a lower proportion of Aeromonas sp. These results indicate that the consumption of a diet containing RG can lead to the accumulation of more beneficial microorganisms while inhibiting the growth of potential pathogens. Moreover, Crenarchaeota, the methanogenic, and Basidiomycota were detected in this study, these populations may be of high physiological relevance in carp because they have been implicated in human health and disease. Our results suggest that an RG-supplemented diet changes the intestinal microbial composition of common carp, which could have positive effects on the immune response of carp.
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Carpas/microbiología , Suplementos Dietéticos , Microbioma Gastrointestinal , Rehmannia , Alimentación Animal/análisis , Animales , Carpas/crecimiento & desarrollo , ARN Ribosómico 16S/genéticaRESUMEN
Plants of the genus Calathea possess many leaf colors, and they are economically important because they are widely used as ornamentals for interior landscaping. Physiological performances and photosynthetic capacities of C. insignis and C. makoyana were investigated. The photosynthetic efficiencies of C. insignis and C. makoyana were significantly increased when the photosynthetic photon flux density (PPFD) increased from 0 to 600 µmol photons·m-2·s-1 and became saturated with a further increase in the PPFD. The two Calathea species had lower values of both the light saturation point and maximal photosynthetic rate, which indicated that they are shade plants. No significant differences in predawn Fv/Fm values (close to 0.8) were observed between dark-green (DG) and light-green (LG) leaf sectors in all tested leaves. However, the effective quantum yield of photosystem II largely decreased as the PPFD increased. An increase in the apparent photosynthetic electron transport rate was observed in both species to a maximum at 600 µmol·m-2·s-1 PPFD, following by a decrease to 1500 µmol·m-2·s-1 PPFD. Compared to LG leaf extracts, DG leaf extracts contained higher levels of chlorophyll (Chl) a, Chl b, Chls a + b, carotenoids (Cars), anthocyanins (Ants), flavonoids (Flas), and polyphenols (PPs) in all plants, except for the Ant, Fla and PP contents of C. insignis plants. Calathea insignis also contained significantly higher levels of total protein than did C. makoyana. The adjusted normalized difference vegetation index (NDVI), photochemical reflectance index (PRI), red-green, and flavonol index (FlavI) were significantly correlated to leaf Chls a + b, Cars, Ants, and Flas in C. makoyana, respectively, and can be used as indicators to characterize the physiology of these plants.
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Fenómenos Químicos , Marantaceae/química , Marantaceae/metabolismo , Fotosíntesis , Clorofila/metabolismo , Luz , Fotones , Pigmentos Biológicos/biosíntesis , Hojas de la Planta/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Metabolismo SecundarioRESUMEN
BACKGROUND: The source and sink relationships between insect-induced galls and host plant leaves are interesting. In this research, we collected cup-like galls induced by Bruggmanniella sp. (Diptera: Cecidomyiidae) on host leaves of Litsea acuminata and assessed them to investigate source-sink relationships between galls and host leaves. We characterized several of their photosynthetic characteristics including chlorophyll fluorescence (Fv/Fm), stomatal conductance, and photosynthetic capacity, biochemical components such as total soluble sugar, starches, free amino acids, and soluble proteins. The structural analyses were performed under confocal, light, and scanning electron microscopies. RESULTS: Compared with host leaves, galls exhibited slightly lower chlorophyll fluorescence; however, stomatal conductance and photosynthetic capacity were not detected at all. Galls accumulated higher total soluble sugars and free amino acids but less soluble proteins than host leaves. No stomata was observed on exterior or interior gall surfaces under light or scanning electron microscopy, but their inner surfaces were covered with fungal hyphae. Confocal imagery showed a gradient of chloroplasts distribution between gall outer and inner surfaces. CONCLUSIONS: Our results strongly suggest that leaf-derived cecidomyiid galls are a type of chlorophyll-deficient non-leaf green tissue and consists on a novel sink in L. acuminate.
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Litsea/fisiología , Litsea/parasitología , Fotosíntesis , Hojas de la Planta/fisiología , Tumores de Planta/parasitología , Aminoácidos/metabolismo , Animales , Metabolismo de los Hidratos de Carbono/efectos de la radiación , Dióxido de Carbono/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/efectos de la radiación , Cloroplastos/ultraestructura , Dípteros/fisiología , Fluorescencia , Litsea/efectos de la radiación , Malondialdehído/metabolismo , Fotosíntesis/efectos de la radiación , Hojas de la Planta/efectos de la radiación , Proteínas de Plantas/metabolismo , Solubilidad , Almidón/metabolismoRESUMEN
Three relevant hypotheses - nutrition, environment and the enemies hypothesis - often invoked to explore source and sink relationships between galls and their host plants are still under dispute. In this research, chlorophyll fluorescence, gas exchange capacity, stomatal conductance, total carbon and nitrogen, total soluble sugars and starches, and scanning and transmission electron microscopy of two types of galls were used to investigate source-sink relationships. Compared with host leaves, these galls demonstrated slightly lower chlorophyll fluorescence; however, gas exchange capacity and stomatal conductance were not detected at all. Scanning electron micrographs demonstrated that the abaxial epidermis of host leaves contain normal amounts of stomata, whereas no stomata were observed on the exterior and interior surfaces of both types of galls. In addition, gall inner surfaces were covered with many kinds of fungal hyphae. Gall total carbon (C) and nitrogen (N) levels were lower but the C/N ratio was higher in galls than host leaves. Both types of galls accumulated higher total soluble sugars and starches than host leaves. Transmission electron micrographs also revealed that both types of galls contain plastoglobuli and giant starch granules during gall development. Results strongly indicate that leaf-derived cecidomyiid galls are sinks in Machilus thunbergii leaves. However, it is perplexing how larvae cycle and balance CO(2) and O(2) in gall growth chambers without stomata.
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Carbono/metabolismo , Dípteros/fisiología , Lauraceae/metabolismo , Nitrógeno/metabolismo , Tumores de Planta/parasitología , Animales , Transporte Biológico , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Interacciones Huésped-Parásitos , Lauraceae/parasitología , Lauraceae/ultraestructura , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Fotosíntesis , Hojas de la Planta/metabolismo , Hojas de la Planta/parasitología , Hojas de la Planta/ultraestructura , Transpiración de PlantasRESUMEN
The distribution of chlorophyll-related compounds (CRCs) derived from dietary spinach was investigated in different organs the rabbits. The rabbits in the experimental group consumed 100 g of freeze-dried spinach powder after a 24 h fasting period and sacrificed 2, 4, 8, 12 and 24 h later and in the control group sacrificed after the 24 h fasting period. The main CRCs in the liver were found to be chlorophyll (Chl a) and b, chlorophyllide (Chlide) a and b, pheophytin (Phe) a and b and pheophorbide (Pho) a and b, which reached their peak values at 8 h post-feeding. The gallbladder contained mainly Chlide a and a', Pho a and a', Pho b and b', which peaked their values at 2 h post-feeding. Pho a and b were consistently observed in the blood and peaked at 12 h post-feeding. The earlier appearance of Chlide a', Pho a' and Pho b' in the gallbladder compared to the liver indicated that these CRCs were compartmentalized differently and might undergo the same type of vectorialized transport as characterized for the bile salts. Pho levels peaked later in the blood compared to the liver, suggesting that Pho might be released into the peripheral blood circulation from the liver. In conclusion, Chlide and Pho were the principal Chl metabolites in the rabbits. Our data may expand our understanding of the metabolism and biodistribution of CRCs in the human body. A number of biological functions, including anti-oxidation, anti-tumor and anti-aging have recently been attributed to CRCs, it will be interesting to explore, if the binding of Chlide and Pho to other nutrients or trace metal ions in the body mediate their biological functions.
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Clorofila/metabolismo , Ingestión de Alimentos/fisiología , Especificidad de Órganos/fisiología , Periodo Posprandial/fisiología , Spinacia oleracea/química , Animales , Femenino , Tasa de Depuración Metabólica , Conejos , Distribución TisularRESUMEN
Amonton's law of friction states that the friction force is proportional to the normal force in magnitude, and the slope gives a constant friction coefficient. In this work, with molecular dynamics simulation, we study how the kinetic friction at the nanoscale deviates qualitatively from the relation. Our simulation demonstrates that the friction behavior between a nanoscale AFM tip and an elastic graphene surface is regulated by the coupling of the applied normal force and the substrate deformability. First, it is found that the normal load-induced substrate deformation could lower friction at low load while increasing it at high load. In addition, when the applied force exceeds a certain threshold another abrupt change in friction behavior is observed, i.e., the stick-slip friction changes to the paired stick-slip friction. The unexpected change in friction behavior is then ascribed to the change of the microscopic contact states between the two surfaces: the increase in normal force and the substrate deformability together lead to a change in the energy landscape experienced by the tip. Finally, the Prandtl-Tomlinson model also validates that the change in friction behavior can be interpreted in terms of the energy landscape.
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Cooking with active oxygen and solid alkali (CAOSA) is an efficient pretreatment method for biomass. For better grading of the lignin yellow liquor, the different lignin fractions and the recovered solid alkali were obtained using a simultaneous acid-alkali graded separation method. The results indicated that the recovery rate of solid alkali was 67.25 %, and the grading of lignin components was characterized by smaller dispersion coefficients, and more stable properties and structure. Lignin fractions with low dispersion coefficients possess more key structures, including the Phenol hydroxyl group (ArOH), Methoxy (OMe), and ß-aryl ether (ß-O-4), and have better thermal properties. The low molecular weight L4 has the highest ArOH content (2.1 mmol/g), which provides better antioxidant properties. The CAOSA process destroyed the S-unit and prevented lignin from condensation. Furthermore, the CAOSA process protected carbohydrates, which could effectively prevent them from dehydrating and re-polymerizing into pseudo-lignin. This allowed the pulp to remain natural, which was beneficial for subsequent transformation and utilization. Overall, the efficient separation of biomass components and lignin grading method proposed by combining the CAOSA process with the acid-alkali grading separation method has a strong application prospect and provides a theoretical basis for the high-value utilization of biomass and lignin.
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Microplastic contamination presents a significant global environmental threat, yet scientific understanding of its morphological distribution within ecosystems remains limited. This study introduces a pioneering method for comprehensive microplastic assessment and environmental monitoring, integrating photoacoustic imaging and advanced deep learning techniques. Rigorous curation of diverse microplastic datasets enhances model training, yielding a high-resolution imaging dataset focused on shape-based discrimination. The introduction of the Vector-Quantized Variational Auto Encoder (VQVAE2) deep learning model signifies a substantial advancement, demonstrating exceptional proficiency in image dimensionality reduction and clustering. Furthermore, the utilization of Vector Quantization Microplastic Photoacoustic imaging (VQMPA) with a proxy task before decoding enhances feature extraction, enabling simultaneous microplastic analysis and discrimination. Despite inherent limitations, this study lays a robust foundation for future research, suggesting avenues for enhancing microplastic identification precision through expanded sample sizes and complementary methodologies like spectroscopy. In conclusion, this innovative approach not only advances microplastic monitoring but also provides valuable insights for future environmental investigations, highlighting the potential of photoacoustic imaging and deep learning in bolstering sustainable environmental monitoring efforts.