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Localized surface plasmon resonance (LSPR) in plasmonic nanoparticles propels the field of plasmo-electronics, holding promise for transformative optoelectronic devices through efficient light-to-current conversion. Plasmonic excitations strongly influence the charge distribution within nanoparticles, giving rise to electromagnetic fields that can significantly impact the macroscopic charge flows within the nanoparticle housing material. In this study, we present evidence of ultralow, unconventional breathing currents resulting from dynamic irradiance interactions between widely separated nanoparticles, extending far beyond conventional electron (quantum) tunneling distances. We develop an electric analogue model and derive an empirical expression to elucidate the generation of these unconventional breathing currents in cascaded nanoplasmonic systems under irradiance modulation. This technique and theoretical model have significant potential for applications requiring a deeper understanding of current dynamics, particularly on large nanostructured surfaces relevant to photocatalysis, energy harvesting, sensing, imaging, and the development of future photonic devices.
RESUMEN
The biogenic synthesis of CuO and ZnO nanoparticles (NPs) was carried out by Stenotrophomonas maltophilia. The shape, size, and chemical identity of the CuO and ZnO NPs were determined using FTIR, XRD, SEM, EDX, and TEM analysis. The study aimed to investigate the effects of the CuO and ZnO NPs on Amaranthus hybridus seed germination and plant growth. Two different fertilizer application modes (hydroponics and foliar) were studied with varying concentrations of CuO (0.06 µM, 0.12 µM) and ZnO (0.12 µM, 0.24 µM) nanoparticles with water control and Hoagland's media control. The hydroponic system of fertilizer application demonstrated better efficiency in terms of plant growth as compared to the foliar application. The agronomic traits, SPAD value, total reducing sugars, antioxidant activity, amount of copper, and zinc ions in root and shoot were analyzed for all experimental plants and found better with the nanoparticle application. The highlight of the study is the application of extremely low concentrations of CuO and ZnO nanoparticles, almost 70% lower than the copper and zinc salts in the Hoagland's medium for improved plant growth. The use of lower concentrations of nanoparticles can prevent their accumulation in the environment and also lower the production cost. The high antioxidant concentration exhibited by the plants treated with CuO and ZnO nanoparticles ensures the enhanced plant's resistance to infections and pests while promoting plant growth.
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Advances in food processing and food packaging play a major role in keeping food safe, increasing the shelf life, and maintaining the food supply chain. Good packaging materials that enable the safe travel of food are often non-degradable and tend to persist in the environment, thereby posing a hazard. One alternative is to synthesize biodegradable polymers with an antimicrobial property while maintaining their mechanical and thermal properties. In the present study, biodegradable composites of PVA-starch-glycerol (PSG) incorporated with CuO and ZnO nanoparticles (NPs) were prepared as PSG, PSG-Cu, PSG-Zn, and PSG-CuZn films. Scanning electron microscopy, energy dispersive x-ray analysis, and thermogravimetric analysis were performed to study and characterize these films. The water barrier properties of the films improved significantly as the hydrophobicity of the PSG-CuZn film increased by 32.9% while the water absorptivity and solubility decreased by 51.49% and 60% compared to the PSG film. The Young's modulus of the films incorporated with CuO and ZnO nanoparticles was lower than that reported for PVA, suggesting that the film possessed higher flexibility. The thermogravimetric analysis demonstrated high thermal stability for films. Biosynthesized CuO and ZnO nanoparticles exhibited antifungal activity against vegetable and fruit spoilage fungi, and hence the fabricated polymers incorporated with nanoparticles were anticipated to demonstrate an antifungal activity. The nanoparticle incorporated films exhibited fungicidal and bactericidal activity, suggesting their role in extending the shelf life of packaged food. The result of ICP-OES studies demonstrated the steady release of ions from the polymer films, however, EDX analysis demonstrated no leaching of CuO and ZnO nanoparticles from the films, thus ruling out the possibility of nanoparticles entering the packaged food. The strawberries wrapped with the fabricated films incorporated with nanoparticles demonstrated improved shelf life and retained the nutritional quality of the fruit. Among the four films, PSG-CuZn was the most promising for food wrapping since it exhibited better water-resistance, antimicrobial, thermal, and mechanical properties.
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Abstract Identifying naturally existing abiotic-stress tolerant accessions in cereal crops is central to understanding plant responses towards stress. Salinity is an abiotic stressor that limits crop yields. Salt stress triggers major physiological changes in plants, but individual plants may perform differently under salt stress. In the present study, 112 barley accessions were grown under controlled salt stress conditions (1 Sm-1 salinity) until harvest. The accessions were then analyzed for set of agronomic and physiological traits. Under salt stress, less than 5 % of the assessed accessions (CIHO6969, PI63926, PI295960, and PI531867) displayed early flowering. Only two (< 2 %) of the accessions (PI327671 and PI383011) attained higher fresh and dry weight, and a better yield under salt stress. Higher K+ /Na+ ratios were maintained by four accessions PI531999, PI356780, PI452343, and PI532041. These top-performing accessions constitute naturally existing variants within barley's gene pool that will be instrumental to deepen our understanding of abiotic-stress tolerance in crops.
Resumen La identificación de accesiones existentes en condiciones naturales que sean tolerantes al estrés abiótico en cultivos de cereales es fundamental para entender las respuestas al estrés. La salinidad es un factor de estrés abiótico que limita el rendimiento de los cultivos. El estrés por salinidad desencadena importantes cambios fisiológicos en las plantas, pero plantas individuales pueden comportarse diferencialmente bajo este tipo de estrés. En el presente estudio se hicieron crecer 112 accesiones de cebada bajo condiciones controladas de estrés por salinidad (1 Sm-1 salinidad) hasta la cosecha. Posteriormente las accesiones se analizaron para determinar sus caracteres agronómicos y fisiológicos. Bajo condiciones de estrés por salinidad, menos del 5 % de las accesiones estudiadas (CIHO6969, PI63926, PI295960 y PI531867) mostraron floración temprana. Solamente dos (< 2 %) de las accesiones (PI327671 y PI383011) alcanzaron mayores pesos fresco y seco y un mayor rendimiento bajo estrés por salinidad. Se mantuvieron mayores proporciones K+/Na+ en cuatro accesiones PI531999, PI356780, PI452343 y PI532041. Estas accesiones que tuvieron el mejor rendimiento constituyen las variantes existentes en condiciones naturales dentro del acervo genético de la cebada, que pueden ser instrumentos para profundizar en nuestro entendimiento de la tolerancia de los cultivos al estrés abiótico.
Resumo A identificação de acessões existentes em condições naturais que sejam tolerantes ao estresse abiótico em culturas de cereais é fundamental para entender a resposta ao estresse. A salinidade é um fator de estresse abiótico que limita o rendimento das culturas. O estresse por salinidade desencadeia importantes mudanças fisiológicas nas plantas, no entanto, plantas individuais podem se comportar diferentemente sob este tipo de estresse. No presente estudo 112 acessões de cevada foram cultivadas sob condições controladas de estresse por salinidade (1 Sm-1 salinidade) até a colheita. Porteriormente, as acessões foram analizadas para determinar suas características agronômicas e fisiológicas. Sob condições de estresse por salinidade, menos de 5 % das acessões estudadas (CIHO6969, PI63926, PI295960 e PI531867) mostraram floração prematura. Somente duas (< 2 %) acessões (PI327671 e PI383011) atingiram maiores pesos frescos e secos e um maior redimento sob estresse por salinidade. As maiores proporções K+/Na+ foram mantidas em quatro acessões PI531999, PI356780, PI452343 e PI532041. As acessões com maior rendimento constituem as variantes existentes em condições naturais dentro do fundo genético da cevada, que podem ser instrumentos para aprofundar no nosso entendimento da tolerância dos cultivos ao estresse biológico.
RESUMEN
ABSTRACT Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to cause gastrointestinal damage. New anti-inflammatory drugs have been developed in an attempt to improve their gastrointestinal side effect profile. Therefore, the objective of the present study was to compare the effect of three different NSAIDs, aspirin, nimesulide, and celecoxib, on the lipid profile and dynamics of rat intestinal brush border membranes (BBMs). Female Wistar rats were divided into four different groups viz: group I (control), group II (aspirin treated), group III (nimesulide treated), and group IV (celecoxib treated). Groups II, III, and IV received the corresponding drugs orally at a dose of 40 mg/kg body weight dissolved in water, while the control group received the vehicle only. After 28 days, all the treatment groups showed modification in the lipid profile of intestinal BBM as compared to control. Alterations in the intestinal membrane dynamics by fluidity studies showed a considerable increase, which correlated well with the changes in the lipid composition. It was suggested that NSAIDs such as aspirin, nimesulide, and celecoxib pose intestinal side effects due to initial changes in the composition and dynamics of the membranes. It was further concluded that newly discovered NSAIDs such as celecoxib have better safety profiles because of the less intense membrane effects, but studies are still required to comment decisively on the suitability of various NSAIDs depending upon their cyclooxygenase enzyme specificity.
