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This work presents an optically transparent and flexible MIMO antenna that features two square patch elements placed in close proximity, aiming to meet the demands of compactness, flexibility, optical transparency, and visual appeal for IoT applications and future 5G wireless communication. The design includes a simple offset fed configuration to achieve the required isolation and impedance matching. It simplifies the process of creating closely spaced transparent MIMO antenna configurations. By optimizing and analyzing this structure, the antenna achieves better isolation and diversity gain performance, even when the patch elements are positioned very close to each other. To achieve optical transparency and flexibility, the antenna uses thin polyethylene terephthalate (PET) material as a substrate, which is a thermoplastic polymer resin from the polyester family. The wired metal mesh parameters for conducting parts of the MIMO antenna and offset position of the feed are carefully optimized to achieve required optical transparency, isolation, impedance matching and radiation performance without any complex decoupling or impedance matching network.
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In this letter, a compact, planar circularly polarized (CP) sub-GHz slot-based multiple-input-multiple-output (MIMO) antenna with dual sense CP along with polarization bandwidth reconfigurability is presented. The pentagonal reactively loaded slot is fed by two folded tapered feedlines to achieve CP. The antenna offers left-hand-circular polarization (RHCP) with the as well as right hand circular polarization (LHCP). The antenna exhibit linearly polarization (LP) by exciting two ports simultaneously. Moreover, the antenna CP resonance can be reconfigured by varying the capacitance of the varactor diode. The antenna has a wide -10 dB operating frequency band from 578-929 MHz. while the axial ratio (AR) bandwidth ranges from 490-810 MHz. Moreover, the two elements MIMO are optimized and placed on compact dimensions 100 × 100 × 0.76 mm3 to realize pattern diversity. The antenna's key characteristics are compact size, wide-band sub-GHz operation, dual sense CP, polarization bandwidth reconfigurability and good MIMO performance. Thus, it is a suitable candidate to be utilized in CubeSats applications in sub-GHz bands.
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A compact, conformal, all-textile wearable antenna is proposed in this paper for the 2.45 GHz ISM (Industrial, Scientific and Medical) band. The integrated design consists of a monopole radiator backed by a 2 × 1 Electromagnetic Band Gap (EBG) array, resulting in a small form factor suitable for wristband applications. An EBG unit cell is optimized to work in the desired operating band, the results of which are further explored to achieve bandwidth maximization via floating EBG ground. A monopole radiator is made to work in association with the EBG layer to produce the resonance in the ISM band with plausible radiation characteristics. The fabricated design is tested for free space performance analysis and subjected to human body loading. The proposed antenna design achieves bandwidth of 2.39 GHz to 2.54 GHz with a compact footprint of 35.4 × 82.4 mm2. The experimental investigations reveal that the reported design adequately retains its performance while operating in close proximity to human beings. The presented Specific Absorption Rate (SAR) analysis reveals 0.297 W/kg calculated at 0.5 W input power, which certifies that the proposed antenna is safe for use in wearable devices.
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A miniaturized folded dipole patch antenna (FDPA) design for biomedical applications operating at sub 1 GHz (434 MHz) band is presented. Antenna is fabricated on FR-4 substrate material having dimensions of 16.40 mm [Formula: see text] 8.60 mm [Formula: see text] 1.52 mm (0.023[Formula: see text] [Formula: see text] 0.012[Formula: see text] [Formula: see text] 0.002[Formula: see text]). Indirect feed coupling is applied through two parallel strips at bottom layer of the substrate. The antenna size is reduced by 83% through lumped inductor placed at the center path of the radiating FDPA, suitable for biomedical (implantable) applications and hyperthermia. Moreover, Impedance matching is achieved without using any Balun transformer or any other complex matching network. The proposed antenna provides an impedance bandwidth of 6 MHz (431-437 MHz) below - 10 dB and a gain of - 31 dB at 434 MHz. The designed antenna is also placed on a human body model to evaluate its performance for hyperthermia through Specific Absorption Rate (SAR), Effective Field Size (EFS), and penetration depth (PD).
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Suministros de Energía Eléctrica , Fiebre , Humanos , Impedancia Eléctrica , HipertermiaRESUMEN
This study was designed to evaluate the emulsifying and rheological properties of acorn protein isolate (API) in different pH mediums (pH 3, 7 and 9) and in the presence of ionic salts (1 M NaCl and 1 M CaCl2). API shows higher solubility in distilled water at pH 7, while at the same pH, a decrease in solubility was observed for API in the presence of CaCl2 (61.30%). A lower emulsifying activity index (EAI), lower stability index (ESI), larger droplet sizes and slight flocculation were observed for API in the presence of salts at different pHs. Importantly, CaCl2 treated samples showed relevantly higher EAI (252.67 m2/g) and ESI (152.67 min) values at all pH as compared to NaCl (221.76 m2/g), (111.82 min), respectively. A significant increase in interfacial protein concentration (4.61 mg/m2) was observed for emulsion at pH 9 with CaCl2, while the major fractions of API were observed in an interfacial layer after SDS-PAGE analysis. All of the emulsion shows shear thinning behavior (τc > 0 and n < 1), while the highest viscosity was observed for emulsion prepared with CaCl2 at pH 3 (11.03 ± 1.62). In conclusion, API, in the presence of ionic salts at acidic, neutral and basic pH, can produce natural emulsions, which could be substitutes for synthetic surfactants for such formulations.
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Quercus , Sales (Química) , Cloruro de Calcio , Emulsionantes/química , Emulsiones/química , Concentración de Iones de Hidrógeno , Proteínas , Reología , Cloruro de SodioRESUMEN
In recent years, biomass energy tends to be one of the important sources of renewable energy in the world. The main objective of current research is to evaluate the impact of biomass energy on the economic growth of NEXT-11 economies. The data used in "the study is based on panel data of NEXT-11 covering the period 1990 to 2019. The included variables are GDP, biomass energy (BE) school enrollment gross ratio (SEGR; trade openness (TO; population growth (PG; and CO2 emission (CO2)." For estimation, this study applied the fully modified ordinary least square (FMOLS) and dynamic ordinary least square (DOLS) approaches. The results of FMOLS and DOLS analysis indicate a statistically significant and positive relationship among all the variables in our sample of nations. According to the findings, an increase in biomass energy use tends to positively affect economic growth. To meet the challenge of global warming, these countries need to increase their technical development and inventions as well as they need to improve biomass energy use.
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Dióxido de Carbono , Desarrollo Económico , Biomasa , Dióxido de Carbono/análisis , Análisis de los Mínimos Cuadrados , Energía RenovableRESUMEN
Both 3-hydroxy-2-butanone and triethylamine are highly toxic and harmful to human health, and their chronic inhalation can cause respiratory diseases, eye lesions, dermatitis, headache, dizziness, drowsiness, and even fatality. Developing sensors for detecting such toxic gases with low power consumption, high response with superselectivity, and stability is crucial for healthcare and environmental monitoring. This study presents a typical gas sensor fabricated based on AuPdO modified Cu-doped K2W4O13 nanowires, which can selectively detect 3-hydroxy-2-butanone and triethylamine at 120 and 200 °C, respectively. The sensor displays excellent sensing performance at reduced operating temperature, high selectivity, fast response/recovery, and stability, which can be attributed to a synergistic effect of Cu dopants and AuPdO nanoparticles on the K2W4O13 host. The enhanced sensing response and selectivity could be attributed to the oxygen vacancies/defects, bandgap excitation, the electronic sensitization, the reversible redox reaction of PdO and Cu, the cocatalytic activity of AuPdO, and Schottky barrier contacts at the interface of tungsten oxide and Au. The significant variations in the activation capacities of Cu-doped K2W4O13, Pd/PdO, and Au nanoparticles toward 3H-2B and TEA, and the diffusion depth of the two gases in the coated sensing layer may cause dual selectivity. The designed gas sensor materials can serve as a sensitive target for detecting toxic biomarkers and hold broad application prospects in food and environmental safety inspection.
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This study aims to extract acorn protein isolate (API) from locally abundant waste acorn fruit and investigate its emulsification behavior by mixing different protein (0.1-2% w/v) and oil volume concentrations (5-45% v/v). Significant decrease in emulsifying activity index (EAI) and an increase in emulsifying stability index (ESI) were observed with an increase in API concentrations (P < 0.05). Droplet sizes of emulsions and viscosity were observed to decrease significantly (P < 0.05) with increase in API concentration while the increase was observed in interfacial protein concentration (Ð). In contrast, increase in oil volume concentration results in increase of droplet sizes, packing fractions and viscosity, while decrease in Ð values was observed. The results reveal that main fractions of API (66.2-14.4 kDa) were migrated to oil-water interface for emulsion stabilization. These results demonstrate the potential application of API in food formulation and development.
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Emulsionantes/química , Aceites/química , Proteínas de Plantas/química , Quercus/metabolismo , Electroforesis en Gel de Poliacrilamida , Emulsiones/química , Frutas/metabolismo , ViscosidadRESUMEN
In this paper, we investigated the association between CO2 emissions, remittances, income, energy use, and foreign direct investment (FDI) through panel cointegration analysis, common correlated effect mean group (CCEMG), fully modified least squares (FM-LS) estimates, and panel causality test for the Brazil, Russia, India, China, and South Africa (BRICS) economies over 1986-2016. The empirical outcomes of CCEMG and FM-LS clarified that remittance inflows into BRICS region are contributing to environmental degradation. Similarly, results in the case of Brazil, Russia, and China supported the remittances-led emission hypothesis. On the other hand, different results have been reached in India, thus the remittances; inflows have dictated that they are helping to combat CO2 emission. Furthermore, FDI has a positive and significant sign for BRICS economies. This relationship narrated that the FDI inflows to this region increase the CO2 emission, hence obeying the pollution haven hypothesis. Finally, energy use also supports the energy-led emanation phenomenon in BRICS panel and alongside the countries. The panel causality test confirms the bidirectional linkage between remittances and CO2 emissions.
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Dióxido de Carbono/análisis , Desarrollo Económico , Brasil , China , India , Federación de Rusia , SudáfricaRESUMEN
The study's main purpose is to investigate the complex interaction between innovation, renewable energy consumption, and CO2 emissions (CO2e), under the Kuznets curve framework, for BRICS economies from 1980 to 2016. The empirical estimates drwan from the CCEMG technique highlighted the heterogeneous role of innovation. The results indicated that innovation activities have failed to disrupt CO2e in China, India, Russia, and South Africa, except for Brazil. Second, the data showed that renewable energy consumption has mitigated CO2e in the BRICS panel, Russia, India, and China, excluding South Africa. Third, the existence of the EKC hypothesis was confirmed in all the BRICS economies, excluding India and South Africa. Fourth, the causality estimations reflected a two-way causality between innovation and CO2e; innovation and GDP per capita; innovation and renewable energy consumption; and between CO2e and income, thereby confirming the acceptance of income-led emission hypothesis in for BRICS economies, and vice versa.
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Dióxido de Carbono/análisis , Desarrollo Económico , Brasil , China , Renta , India , Energía Renovable , Federación de Rusia , SudáfricaRESUMEN
In this study, the Maillard reaction (MR) of glucose was applied to improve the physicochemical and functional properties of walnut protein isolate (WNPI). The MR products (MRPs) were prepared with glucose at 0 h (MRP0), 1 h (MRP1), 2 h (MRP2) and 3 h (MRP3) heating at 95 °C. The Infra-Red spectrum showed reduction of amide and S-H functionalities in MRPs with complete intermixing of glucose in MRP3. Scanning electron microscopy indicated changes in the morphology of MRP3 which also exhibited promising antioxidant effect. Significant decrease (P < 0.05) in hydrophobicity values (Ho) and increase (P < 0.05) in emulsifying activity/emulsifying stability indexes values were observed for MRPs. Uniform droplet distribution was observed in microscopy of emulsions while an increase in the interfacial protein concentration ( Ð) was obtained for MRPs. These results suggest that MR is useful in improving the utilization of this protein in food product development.
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A comparison between a graphene suspended double-layer modulator and a subwavelength-thickness modulator is presented. The physics of both are analyzed in detail and show a confined mode in the suspended modulator but a leaky mode in the subwavelength modulator. The leaky mode shows zero light-matter interaction and zero modulation depth, which should be avoided in designing a modulator. The suspended modulator can achieve much lower insertion loss and an extraordinarily higher figure of merit (â¼2480) than the subwavelength modulator. Both operate with high modulation efficiency and comparable modulation speeds. We believe these designs will pave the way to realizing high-efficiency, near-fundamental-limit graphene modulators.
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BACKGROUND: Orthokeratinized Odontogenic Cyst (OOC) is a rare, developmental odontogenic cyst which was considered in the past to be a variant of Odontogenic keratocyst (OKC) later renamed as keratocystic odontogenic tumor (KCOT). The treatment of OOC is by enucleation and the prognosis, following enucleation is excellent with a recurrence rate of less than 2%. On the other hand, OKC has a recurrence rate between 8 and 25% after enucleation. Thus it is important to differentiate between the two entities. METHODS: All cases reported in our section as OOC during the period 2013 to 2018 were retrieved from the surgical pathology files and slides were reviewed by the authors. All cases which met the histological criteria for OOC were included. RESULTS: A total of 10 cases were included. 70% patients were males, ages ranged from 23 to 60 years, with mean age of 38.9 years. 70% of cases were located in the mandible and 90% patients presented with swelling. Radiologically, 90% cases were unilocular, all were radiolucent lesions. Mean size was 4.0 cm. Histologically, all cases demonstrated the classic microscopic features. Follow-up was available in 8 patients. All were treated by enucleation. All 8 were alive with no recurrences over a follow-up period ranging from 7 to 62 months. CONCLUSIONS: OOC has a better prognosis than OKC and needs to be differentiated from OKC due to differences in treatment and prognosis. Large majority of our cases presented with swelling and occurred in the mandibles of young males. All were radiolucent and most were unilocular. All were treated by enucleation and no recurrences occurred over follow up period ranging up to 62 months. Our findings were similar to those described in other published series.
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Tumores Odontogénicos/patología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Quistes Odontogénicos/diagnóstico por imagen , Quistes Odontogénicos/patología , Tumores Odontogénicos/diagnóstico por imagen , Radiografía , Adulto JovenRESUMEN
Measuring temperature and heat flux is important for regulating any physical, chemical, and biological processes. Traditional thermopiles can provide accurate and stable temperature reading but they are based on brittle inorganic materials with low Seebeck coefficient, and are difficult to manufacture over large areas. Recently, polymer electrolytes have been proposed for thermoelectric applications because of their giant ionic Seebeck coefficient, high flexibility and ease of manufacturing. However, the materials reported to date have positive Seebeck coefficients, hampering the design of ultra-sensitive ionic thermopiles. Here we report an "ambipolar" ionic polymer gel with giant negative ionic Seebeck coefficient. The latter can be tuned from negative to positive by adjusting the gel composition. We show that the ion-polymer matrix interaction is crucial to control the sign and magnitude of the ionic Seebeck coefficient. The ambipolar gel can be easily screen printed, enabling large-area device manufacturing at low cost.
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We suggest gelatin hydrogel as an electrolyte and demonstrate organic electrochemical transistors (OECTs) based on a sheet of gelatin. We also modulate electrical characteristics of the OECT with respect to pH condition of the gelatin hydrogel from acid to base and analyze its characteristics based on the electrochemical theory. Moreover, we extend the gelatin-based OECT to electrochemical logic circuits, for example, NOT, NOR, and NAND gates.
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The effect of different extraction methods i.e. extraction with alkali (AEDF), enzyme (EEDF) and enzyme plus shear emulsifying hydrolysis (SEDF) on structure, physiochemical as well as the functional characteristics of dietary fiber (DF) from defatted walnut flour were studied. AEDF process showed significantly higher (P < 0.05) amount of water retention capacity (WRC; 5.39 g/g), water swelling capacity (WSC; 3.16 g/mL), and particle size; while, shown lower value of oil adsorption capacity (OAC; 29 g/g) amongst all. Compared to AEDF, no major differences were observed in network except the matrix in EEDF and SEDF was more porous and honey comb like. DF extracted through AEDF, EEDF and SEDF showed good viscosity and emulsifying activity however, less stability indices. The results from this study suggest that AEDF and EEDF and SEDF had specific effects on the structure-functional properties of DF from defatted walnut flour, which has great potential in food applications.
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The drug resistant bacteria and textile contaminations of water cause different sever health problem throughout the world. To overcome this issue, new environmental benign materials and methods are needed. Plant metabolites directed synthesis of nanoparticles is considered eco-friendly and easy in synthesis. Therefore, it was explicit for the synthesis of AgNPs. The prepared AgNPs were evaluated for antibacterial, antioxidant, photo-catalytic and electrochemical degradation properties as well as toxicity of degradation products on aquatic life. X-Ray Photoelectron Spectroscopy (XPS) has been used for analyzing the surface chemistry of prepared AgNPs. The particle size determines the interaction of nanoparticles with pathogens. Both Gram positive and negative bacteria (Escherichia coli and Staphylococcus areous) are used to determine the anti-microbial potency of the green synthesized AgNPs. The synthesized silver nanoparticles showed significant anti-bacterial applications against B. subtilus and S. aureus. The anti-oxidant applications of AgNPs also studied on comparison with vitamin C. The toxicity of the phenolic Azo dyes (PDA) has been studied against Fish, Daphnia and Green Algae. The electrode potential was studied in the electrochemical redox reaction of hydroxy phenol in aqueous media. Simple electrolyte was used to determine the current efficiency. For the stability of electrode multi cyclic voltammetry was also studied during redox reaction, which showed stability under the potential 0.4 to 0.2â¯V.
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Antiinfecciosos/química , Antioxidantes/química , Compuestos Azo/química , Nanopartículas del Metal/química , Plata/química , Animales , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Compuestos Azo/toxicidad , Chlorophyta/efectos de los fármacos , Daphnia/efectos de los fármacos , Técnicas Electroquímicas , Electrodos , Peces/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Nanopartículas del Metal/toxicidad , Pruebas de Sensibilidad Microbiana , Fenoles/química , Espectroscopía de FotoelectronesRESUMEN
Some new pyrimidine derivatives have been synthesised by electrochemical oxidation of catechol (1a) in the existence of 2-mercapto-6-(trifluoromethyl) pyrimidine-4-ol (3) as a nucleophile in aqueous solution using Cyclic Voltammetric and Controlled Potential Coulometry. The catechol has been oxidised to o-quinone through electrochemical method and participative in Michael addition reaction, leading to the development of some new pyrimidine derivatives. The products were achieved in good yield with high pureness. The mechanism of the reaction has been conformed from the Cyclic Voltammetric data and Controlled Potential Coulometry. After purification, the compounds were characterised using modern techniques. The synthesised materials were screened for antimicrobial actions using Gram positive and Gram negative strain of bacteria. These new synthesised pyrimidine derivatives showed very good antimicrobial activity.
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Antibacterianos/síntesis química , Antibacterianos/farmacología , Catecoles/química , Antibacterianos/química , Evaluación Preclínica de Medicamentos/métodos , Técnicas Electroquímicas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Radical Hidroxilo , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Fenol/química , Pirimidinas/química , Quinonas/químicaRESUMEN
Fresh button mushrooms (Agaricus bisporus) were harvested and treated with a solution of 1.5% CaCl2 + 0.5% citric acid and stored for 16 days at 12 °C. The effects of this treatment on firmness, weight, color, cell wall compositions (cellulose and chitin) and cell wall degrading enzymes (cel1ulase, beta-1, 3 glucanase, chitinase and phenylalanine ammonialyase) were investigated during post-harvest storage. The expressions of major genes (Cel1, Glu1, Chi1 and PAL1) involved in cell wall degradation during post-harvest storage were also monitored. The results revealed that the post-harvest chemical treatment maintained better firmness, weight, color and inhibited cellulase, beta-1, 3 glucanase, chitinase and phenylalanine ammonialyase activities. These findings showed that the down-regulation of cell wall degrading enzymes is a possible mechanism that delays the softening of button mushrooms by the application of combined chemical treatment.