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Angle-dependent next-generation displays have potential applications in 3D stereoscopic and head-mounted displays, image combiners, and encryption for augmented reality (AR) and security. Metasurfaces enable such exceptional functionalities with groundbreaking achievements in efficient displays over the past decades. However, limitations in angular dispersion control make them unfit for numerous nanophotonic applications. Here, we propose a spin-selective angle-dependent all-dielectric metasurface with a unique design strategy to manifest distinct phase information at different incident angles of light. As a proof of concept, the phase masks of two images are encoded into the metasurface and projected at the desired focal plane under different angles of left circularly polarized (LCP) light. Specifically, the proposed multifunctional metasurface generates two distinct holographic images under LCP illumination at angles of +35 and -35°. The presented holographic displays may provide a feasible route toward multifunctional meta-devices for potential AR displays, encrypted imaging, and information storage applications.
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Dye solubilization in microemulsion based on Cetyltrimethylammonium bromide (CTAB) and its modified forms (counter-anions based upon Zn2+, Cu2+ and Fe3+) is comparatively innovative and not explored in existing literature. Here, surfactant with modified counterions (SMCs) were used to study the effects of metal chlorides (ZnCl2, CuCl2 and FeCl3) modifications on the comparative solubilization of Rhodamine-B (RB) by Cetyltrimethylammonium bromide (CTAB) and its modified forms. The solubility of RB in different microemulsions were studied using UV-Visible spectroscopy and phase diagrams of CTAB with modified counter ions CTA+[ZnCl2.Br]- named as CZN-1, CTA+[CuCl2.Br]- named as CCU-1 and CTA+[FeCl3.Br]- named as CFE-1 based upon surfactant with modified counter ions (SMCs). Four different points in microemulsion region of phase diagram were selected with different percentage composition of Smix (surfactant and co-surfactant), oil and RB (taken as water component). The interaction of RB, CCU-1, CFE-1 and CZN-1 within microemulsion environment were studied using Fluorescence spectroscopy. Emission spectra of RB in CCU-1 and CFE-1 based microemulsion confirmed that RB formed complexes with Cu and Fe ions. It was also found that RB was less soluble in CTAB based microemulsion as compared to microemulsions based on SMCs. This novel research study will expose new path for future research work related to microemulsion.
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Nitrite ions (NO2-), as one of the leading type-A inorganic-anion, showing significant-effects in the aquatic environment and also to humans health. Whereas, the higher uptake causes detrimental threat to human health leading to various chronic diseases, thus demanding efficient, reliable and convenient method for its monitoring. For this purpose, in the present research study we have fabricated the mimetic nonozyme like catalyst based colorimetric nitrite sensor. The acetic acid capped Zinc Oxide (ZnO) nanosheets (NSs) were introduce as per-oxidase mimetic like catalyst which shows high efficiency towards the oxidative catalysis of colorless tetramethylbenzidine (TMB) to oxidized-TMB (blue color) in the presence of Hydrogen-peroxide (H2O2). The present nitrite ions will stimulate the as formed oxidized-TMB (TMBox), and will caused diazotization reaction (diazotized-TMBox), which will not only decreases the peak intensity of UV-visible peak of TMBox at 652 nm but will also produces another peak at 446 nm called as diazotized-TMBox peak, proving the catalytic reaction between the nitrite ions and TMBox. Further, the prepared colorimetric sensor exhibits better sensitivity with a wider range of concentration (1 × 10-3-4.50 × 10-1 µM), lowest limit of detection (LOD) of 0.22 ± 0.05 nM and small limit of quantification (LOQ) 0.78 ± 0.05 nM having R2 value of 0.998. Further, the colorimetric sensor also manifest strong selectivity towards NO2- as compared to other interference in drinking water system. Resultantly, the prepared sensor with outstanding repeatability, stability, reproducibility, re-usability and its practicability in real water samples also exploit its diverse applications in food safety supervision and environmental monitoring.
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Arsenic is a highly toxic metal that causes cancer even at a low concentration and its removal from water resources is challenging. Herein, carbon extracted from waste onion bulbs is activated to cater for porosity and functionalized with magnetite (Fe3O4) nanoparticles (named MCK6) to address the challenge of As(III) removal. Synthesized MCK6 was highly mesoporous having a surface area of 208 m2/g, where magnetite nanoparticles (≤ 10 nm) are homogeneously distributed within a porous network. The developed adsorbent inherited functional groups from the biosource and magnetic property from magnetite making it ideal for removal of As(III). Further, MCK6 showed a maximum monolayer adsorption capacity (qm) of 10.2 mg/g at 298 K and pH 7. The adsorption thermodynamics delineates a non-spontaneous and endothermic reaction, where the kinetics followed pseudo 2nd order (R2 value of 0.977), while monolayer formation is explained by the Langmuir model. Moreover, MCK6 efficiently works to remove As(III) in a competitive metal ions system including Pb+2, Cd+2, and Ca+2, making it a suitable adsorbent to tackle contaminated water.
Assuntos
Nanopartículas de Magnetita , Poluentes Químicos da Água , Purificação da Água , Água/química , Óxido Ferroso-Férrico , Porosidade , Carbono , Poluentes Químicos da Água/análise , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Nanopartículas de Magnetita/químicaRESUMO
Gut microbiota interacts with host epithelial cells and regulates many physiological functions such as genetics, epigenetics, metabolism of nutrients, and immune functions. Dietary factors may also be involved in the etiology of colorectal cancer (CRC), especially when an unhealthy diet is consumed with excess calorie intake and bad practices like smoking or consuming a great deal of alcohol. Bacteria including Fusobacterium nucleatum, Enterotoxigenic Bacteroides fragilis (ETBF), and Escherichia coli (E. coli) actively participate in the carcinogenesis of CRC. Gastrointestinal tract with chronic inflammation and immunocompromised patients are at high risk for CRC progression. Further, the gut microbiota is also involved in Geno-toxicity by producing toxins like colibactin and cytolethal distending toxin (CDT) which cause damage to double-stranded DNA. Specific microRNAs can act as either tumor suppressors or oncogenes depending on the cellular environment in which they are expressed. The current review mainly highlights the role of gut microbiota in CRC, the mechanisms of several factors in carcinogenesis, and the role of particular microbes in colorectal neoplasia.
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Objective: This study aims to evaluate the immunomodulatory effects of coconut oil extract (COE) in broilers experimentally infected with velogenic Newcastle disease virus (vNDV). Methods: A total of 150 broiler birds (day-old) were equally divided into five study groups i.e., negative control, positive control, COE-1, COE-2, and COE-3. On day 10, broilers of groups COE-1, COE-2, and COE-3 were supplemented with 1, 2, and 3 ml of COE respectively per liter of drinking water for 15 days. On day 13, 0.1ml/bird (10-5.25 ELD50) of vNDV was inoculated in broilers of positive control, COE-1, COE-2, and COE-3 groups intramuscularly. During this study, growth performance, morbidity, and mortality rates of each study group were recorded. The antibody titer against NDV was determined on days 7, 14, 21, 28, and 35. The levels of IgY and IgM were also determined on the 7th, 14th, and 21st days post-SRBC inoculation. On day 33, avian tuberculin was injected between the 1st and 2nd toes of the left side (intradermally) to measure lymphoproliferative responses. On day 35, the phagocytic activity in the blood was assessed through a carbon clearance assay by injecting carbon black ink into the right-wing vein. The visceral organs having gross lesions were also collected for histopathology. Results: The COE significantly improved the growth performance, and lowered the morbidity and mortality rates of broilers. There was a significant rise in antibody titers against NDV and levels of IgY and IgM antibodies against SRBC in COE-supplemented broilers. The lymphoproliferative response and phagocytic activity were also enhanced. Among COE-supplemented groups, the broilers of the COE-3 group showed a significant increase in growth performance and boosted immune defense. Conclusions: Coconut oil extract has the potential to boost the growth performance and immune status of broilers. It can be used effectively as a feed additive and alternative to antibiotics to prevent the spread of infectious poultry pathogens.
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Optical wireless communication (OWC), with its blazing data transfer speed and unparalleled security, is a futuristic technology for wireless connectivity. Despite the significant advancements in OWC, the realization of tunable devices for on-demand and versatile connectivity still needs to be explored. This presents a considerable limitation in utilizing adaptive technologies to improve signal directivity and optimize data transfer. This study proposes a unique platform that utilizes tunable, fluid-responsive multifunctional metasurfaces offering dynamic and unprecedented control over electromagnetic wave manipulation to enhance the performance of OWC networks. We have achieved real-time, on-demand beam steering with vary-focusing capability by integrating the fabricated metasurfaces with different isotropic fluids. Furthermore, the designed metasurfaces are capable of polarization-based switching of the diffracted light beams to enhance overall productivity. Our research has showcased the potential of fluid-responsive tunable metasurfaces in revolutionizing OWC networks by significantly improving transmission reliability and signal quality through real-time adjustments. The proposed methodology is verified by designing and fabricating an all-dielectric metasurface measuring 500 µm × 500 µm and experimentally investigating its fluid-responsive vary-focal capability. By incorporating fluid-responsive properties into spin-decoupled metasurfaces, we aim to develop advanced high-tech optical devices and systems to simplify beam-steering and improve performance, adaptability, and functionality, making the devices suitable for various practical applications.