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Vaccination is the most effective means of controlling infectious disease-related morbidity and mortality. However, due to low immunogenicity of viral antigens, nanomedicine as a new opportunity in new generation of vaccine advancement attracted researcher encouragement. Virosome is a lipidic nanomaterial emerging as FDA approved nanocarriers with promising bioinspiration and biomimetic potency against viral infections. Virosome surface modification with critical viral fusion proteins is the cornerstone of vaccine development. Surface antigens at virosomes innovatively interact with targeted receptors on host cells that evoke humoral or cellular immune responses through antibody-producing B cell and internalization by endocytosis-mediated pathways. To date, several nanovaccine based on virosome formulations have been commercialized against widespread and life-threatening infections. Recently, Great efforts were made to fabricate a virosome-based vaccine platform against a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Thus, this review provides a novel overview of the virosome based nanovaccine production, properties, and application on the viral disease, especially its importance in SARS-CoV-2 vaccine discovery. [Display omitted] • Nanomedicine revolutionized vaccine development technology. • Virosome based nanovaccines illustrated strong potentioal in virious viral disease prevention. • Virosomes mimic the native morphology of the virus, by incorporation different types of antigen epitops. • This novel FDA approved platform attracted great effeorts in SARS-CoV2 vaccine development. [ABSTRACT FROM AUTHOR]

In this study, an approach is presented for external network modeling of power systems in the absence of required data involving all of transmission lines and equipment in all of the substations. In the proposed approach which is based on multi-port networks, the studied power system is divided into two parts of surface layer and deep region. The surface layer should be modeled high accuracy, thorough details and frequency dependent. The deep region should be modeled by a multi-port equivalent network. This multi-port equivalent network is achievable using a steady state model of the power system which is under the study. In order to investigate the performance of the proposed approach, numerical studies are performed for a typical network. Results show the high precision of the modeled network in comparison to the complete network. Effectiveness of the presented approach in electromagnetic transient studies of large-scale power systems has been indicated in this paper. [ABSTRACT FROM AUTHOR]

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Ferroresonance is a complex phenomenon, which can result in thermal and electrical stresses on power system equipments. It can also cause chaotic oscillations in power system. In this paper, a new method is proposed to restrict and damp ferroresonant oscillations, which is based on a new of fault current limiter (FCL). In this method in order to restrict chaotic ferroresonance oscillations, a kind of fault current limiters (FCL) is used which has been used to restrict unwanted high current flow in power system before. To study the ferroresonance nonlinear dynamics, in this paper, the chaos theory is used. By using this theory, the changes in system parameters which can cause chaotic ferroresonant oscillations, can be reviewed and analyzed in details. The behavior of the system during ferroresonance occurrence, with and without using proposed FCL, is discussed in bifurcation and phase plane diagrams. By using these diagrams, the behavioral changes of the system can be easily seen in two cases. The simulation results strongly show the effectiveness of using the proposed FCL for restricting the ferroresonant oscillations. [ABSTRACT FROM AUTHOR]

Highlights: [•] The used method in this research to analyze electro-thermal (ET) stresses is FEM. [•] The FEM optimization has been done according the proposed optimization algorithm. [•] So a distributed electrical conductivity for selected insulation layers has been obtained. [•] Semiconductive coating and groundwall insulation are the selected layers. [•] So, ET tensions across the stator slot insulation layers have been reduced. [Copyright &y& Elsevier]

Stevia (Stevia rebaudiana Bertoni) is an important and salt-sensitive medicinal plant used as a natural sweetener in food products. In this work, we used a pot experiment to investigate the role of microbial inoculation and exogenous polyamine spermidine (Spd) in conferring salt stress tolerance in stevia by analyzing plant growth, chlorophyll (Chl) content, Chl a fluorescence, antioxidant defense system and steviol glycosides. The inoculated plants with Piriformospora indica (Pi), Tricuderma virens (Trich) or Pi+Trich were grown in optimum conditions. At the late of vegetative stage (BBCH growth stage 47), plants sprayed with different concentrations of Spd (0, 0.75, and 1.5 mM) and then were exposed to salinity stress by irrigation with saline treatments (mix of Caspian Sea and distilled water; 0, 6, and 12 dS m−1). The results revealed that salt stress increased hydrogen peroxide (H 2 O 2) and lipid peroxidation (Malondialdehyde: MDA), and consequently plant growth characteristics and maximum photochemical quantum yield of PSII (Fv/Fm) as well as Chl content decreased, but antioxidant enzymes activity including superoxide (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) increased in the plants. Exposure to moderate salinity increased stevioside (Stv) and rebaudioside A (Reb A) content, while these compounds were decreased in the presence of severe salinity. The endophytic symbiosis and foliar spray of Spd (especially in Pi+Trich and Spd 0.75 mM) mitigated salt stress by significant increases in antioxidant enzymes activity and a decrease in H 2 O 2 content and lipid peroxidation. Inoculation with Pi, Trich, and especially Pi+Trich increased the Chl content, Fv/Fm, shoot dry weight, and Stv and Reb A content at all salinity levels. Consequently, combined inoculation of Pi and Trich and foliar application of Spd can be a good approach to improve tolerance, growth and steviol glycosides production of stevia in salt stress conditions. [Display omitted] • Irrigation water salinity had deleterious effects on physiological traits of stevia. • Microbial inoculation and spermidine incited the systemic resistance activation. • Foliar application of spermidine improved the photochemical efficiency in stevia. • Combined microbial inoculation exhibited synergistic effect on membrane lipid protection. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, control of chaos is done in presence of ferroresonant oscillations in a voltage transformer with nonlinear model of core losses. In order to control the chaotic oscillations, nonlinear adaptive approach is employed. Moreover, a Time Delay Feedback Controller (TDFC) is implemented to stabilize Unstable Periodic Orbits (UPOs). Also multiple scales method to analyze chaotic behavior and types of fixed points in ferroresonance occurrence at voltage transformers considering different types of core loss models is applied. In the literature ferroresonance phenomenon in voltage transformers is proved to be classified in chaotic dynamics systems. In this contribution, chaos occurs in the system from a sequence of Period Doubling Bifurcation (PDB). This phenomenon consists of different types of bifurcations such as Period Doubling Bifurcation (PDB), Saddle Node Bifurcation (SNB), Hopf Bifurcation (HB) and chaos. Dynamic analysis of ferroresonant circuit is performed using bifurcation theory. bifurcation diagrams and phase plane diagrams are illustrated using a continuation method for linear and nonlinear core loss models. For analyzing ferroresonance phenomenon, Lyapunov exponents are calculated using multiple scales method and feigenbaum numbers are obtained. Bifurcation diagrams illustrate variation of parameter control and as a result chaos is created and increased in the system. [Copyright &y& Elsevier]

One-pot synthesis of azo and sulfonated pyrimido[4,5- b quinoline derivatives was developed by three-component reaction of azo and sulfonated aldehydes, 6-amino-1,3-dimethyluracil, and dimedone or 1,3-cyclohexadione in the presence of choline chloride/oxalic acid (ChCl/Oxa) at 80 °C. The products formed in excellent yields over appropriate reaction times under an environmentally friendly condition. One-pot reaction, high efficiency, and easy purification of products by simple recrystallization are some of the considerable advantages of this procedure. Image 1 • One-pot synthesis of novel azo and sulfonated pyrimido[4,5- b quinoline derivatives was developed. • The three-component reaction was performed in the presence of choline chloride/oxalic acid (ChCl/Oxa) at 80 °C. • The products formed in excellent yields over appropriate reaction times under an environmentally friendly condition. [ABSTRACT FROM AUTHOR]

• Dependency of arc V-I characteristic to electric circuit parameters is shown. • Plasma arc interactions with electric circuit is numerically investigated. • Magnetohydrodynamics equations are coupled with electric circuit equations. The main goal of this letter is the investigation of the interaction of generated plasma arc in SF 6 circuit breakers with electric circuits. According to the electric circuit theory, when there is a nonlinear element in the circuit such as an arc, the intersection of the nonlinear V-I curve of the arc and the circuit V-I curve can be used to find the circuit operating point. In this letter the correctness of this approach for finding the system operating point is interrogated, by using a multi-physic model, including the Navier-Stokes equations and standard K - ε turbulent model for modeling the dynamic of the SF 6 gas, heat equation for calculation of the SF 6 gas temperature, Maxwell equations for electromagnetic fields modeling, gas state equation for taking into account the temperature dependency of SF 6 gas properties, and Kirchhoff's voltage and current laws equations. Numerical studies have been performed during the closing operation of a puffer-type 72.5 kV SF 6 circuit breaker. [ABSTRACT FROM AUTHOR]

• A multi-physics model for simulation of prestrike phenomenon in circuit breakers. • Magnetohydrodynamics equations are coupled with electric circuit equations. • Motion of moving parts and temperature dependency of gas properties are considered. • Plasma arc interactions with electric circuit is numerically investigated. • The effects of resistance and inductance of the source on the arc is studied. Prestrike is a common phenomenon in Circuit Breakers (CB) when the moving contact approaching to the fixed contact during the closing operation. This paper focuses on prestrike modeling in SF 6 circuit breakers. A multi-physics method is developed to accurately modeling the prestrikes in SF 6 circuit breakers. In this study, a model is developed for a simultaneous solution of the MHD equations and the governing equations of the circuit feeding the plasma in order to consider mutual effects of the circuit and the plasma. Navier-Stoke equations, turbulent flow equations, and the equation of heat transfer in fluids, coupled with Maxwell's equations are physical equations governing the circuit breakers. Kirchhoff's voltage and current laws equations are governing equations of the external electric circuit. The Electric-Circuit-Constrained Magnetohydrodynamic (ECC-MHD) model developed in this paper is able to study the electromagnetic properties of conducting fluids fed by electrical circuits. Motion of moving contact and temperature dependency of SF 6 gas properties are considered during the solving of this multi-physics problem. Finite Element Method (FEM) is used to solve the multi-physics equations governing the circuit breaker. Finally a 72 kV single pressure puffer type SF 6 circuit breaker is used for numerical studies. To investigate the mutual effects of the feeding circuit parameters and generated plasma in the circuit breaker, numerical studies are performed for different values of resistance and inductance in the arc current path. [ABSTRACT FROM AUTHOR]

Soft set theory is a map of a set of parameters to the subsets of a universe which can be utilized to parametrically model the uncertainty. On the other hand, Graph (hypergraph) theory is used to simplify some practical problems. Inspired by these concepts, the notion of "soft hypergraph" is developed as the generalization of both soft graph and hypergraph for important application in social media networking. Based on the structure of soft hypergraph, various techniques and operations are provided including soft sub-hypergraph, extended union, extended intersection, cartesian product and complement with elucidatory examples. As per the current global spread of COVID, most of the national and international interactions and social affairs have been virtually conducted via social media networks, such as Skype, Microsoft Teams, WhatsApp, Telegram, Zoom, Instagram, WeChat, etc. For the purpose of Intelligent management of network systems, we use the "generalized soft hypergraph" to model the global e-communication networking of individuals in online platforms. • Generalized theory was created via combining soft set theory and hypergraph theory. • Parametrical model with graphical representation could solve uncertainty problems. • Extended union and intersection were created with complement and cartesian product. • Global social media networks were modeled using the developed "soft hypergraph". • Community detection, expert finding, and influence analysis were investigated. [ABSTRACT FROM AUTHOR]

Air pollution causes extreme toxicological repercussions for human health and ecology. The management of airborne bacteria and viruses has become an essential goal of air quality control. Existing pathogens in the air, including bacteria, archaea, viruses, and fungi, can have severe effects on human health. The photocatalysis process is one of the favorable approaches for eliminating them. The oxidative nature of semiconductor-based photocatalysts can be used to fight viral activation as a green, sustainable, and promising approach with significant promise for environmental clean-up. The photocatalysts show wonderful performance under moderate conditions while generating negligible by-products. Airborne viruses can be inactivated by various photocatalytic processes, such as chemical oxidation, toxicity due to the metal ions released from photocatalysts composed of metals, and morphological damage to viruses. This review paper provides a thorough and evaluative analysis of current information on using photocatalytic oxidation to deactivate viruses. [Display omitted] • Ventilation importance about Covid-19 virus leads to growing popularity of photocatalytic process. • UV-assisted photocatalytic approaches are utilized for deactivating pathogenic microorganisms. • Air filters with antimicrobial features can be helpful to prevent the virus spread. • TiO 2 -based photocatalysts demonstrate antiviral impacts against SARS-CoV-2 viruses. [ABSTRACT FROM AUTHOR]

Hagfish exudate is a natural biological macromolecule made of keratin intermediate filament protein skeins and mucin vesicles. Here, we successfully examined this remarkable biomaterial as a substrate for three-dimensional (3D) cell culturing purposes. After the sterilization with chloroform vapor, Dulbecco's modified eagle medium was mixed with the exudate to rupture the vesicles and skeins; a highly soft, adherent, fibrous and biocompatible hydrogel was formed. A variety of cells, including Hela-FUCCI, NMuMG-FUCCI, 10T1/2 and C2C12, was cultured on the hagfish exudate. A remarkable 3D growth by ~2.5 folds after day 3, ~5 folds after day 5, ~10 folds after day 7 and ~15 folds after day 14 were seen compared to day one of culturing in the hagfish exudate scaffold. In addition, the phase contrast, fluorescent and confocal microscopy observations confirmed the organoid shape formation within the three-week culture. The viability of cells was almost 100% indicating the great in vitro and in vivo potential of this exceptional biomaterial with no cytotoxic effect. • Hagfish exudate was utilized as a novel biomaterial for 3D bio-scaffolding. • Successful tissue growth and organoid formation achieved using hagfish exudate • Natural hagfish exudate was ~100% biocompatible non-cytotoxic substrate for cell culture. • Chloroformization was used as a simple process for sterilization of hagfish exudate. • Simple sonication regulated fibrocity and beaded structure for simulated nerve system. [ABSTRACT FROM AUTHOR]

Highlights • Biochar affected the production of trigonelline in seeds of Fenugreek. • The effect varied between six ecotypes. • The content of diosgenin was not affected by biochar or drought. • In the field, the biochar did not affect the content of any of the two compounds. Abstract Extrinsic factors may be needed to inhibit seed yield reduction and achieve a high yield of secondary metabolites when plants are stressed. Trigonelline and diosgenin are secondary metabolites and important components in medicine and cosmetic. We assessed if charcoal made from rice husk added to the soil could alter the content of these compounds in seeds of six fenugreek ecotypes when plants were grown with and without drought stress in a greenhouse and a field in 2015. In the greenhouse, charcoal significantly affected the trigonelline content, but the response varied between the ecotypes. The ecotypes were divided into three groups based on their response to charcoal: 1. Ecotypes, in which the trigonelline content was reduced (Dezful and KhomeyniShahr); 2. Ecotype, in which the content increased (Yazd); and 3. Ecotypes, which reacted differently to the charcoal application. The third group was divided into two subgroups: a) the ecotype, where the trigonelline content increased by charcoal under drought stress but decreased under well-watered condition (Rehnan) and b) the ecotypes where the trigonelline content declined by charcoal under drought stress but increased under well-watered condition (Shushtar and Ardestan). We concluded the genetic differences need to be considered when charcoal is used as a method for altering the accumulation of secondary metabolites. However, charcoal increased the content of diosgenin in the greenhouse experiment. In the field, the charcoal did not affect the content of the two compounds probably because charcoal made up a tiny proportion of the soil volume. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyoxometalates (POMs) demonstrate an enhanced anti-viral, anti-tumor, and antibacterial activity. • POMs provide a highly biocompatibility and low cytotoxicity. • POMs with extraordinary feature could be effectively considered and utilized for targeted biomedical applications. Polyoxometalate(POMs) is an oligomeric cluster of transition metal oxoanions that has a well-defined infrastructure with a wide range of sizes, metal–oxygen frameworks, chemical compositions, and unparalleled properties. In the fields of catalysis, materials chemistry, and biochemistry, they are among the most attractive and fastest growing areas of research. Moreover, some POMs and their derivatives are capable of exhibiting antibacterial, antiviral, antitumor, and anticancer properties, in addition to their many valuable properties. Several studies have demonstrated the efficacy of some of these agents in the treatment of symptoms associated with diabetes. Because of these properties, POMs have always been of interest to researchers. In this review, an overview of the biomedical applications of POMs, including their role in pharmaceuticals, is provided based on various scientific publications. [ABSTRACT FROM AUTHOR]

Rapid person-to-person transfer of viruses such as SARS-CoV-2 and their occasional mutations owing to the human activity and climate/ecological changes by the mankind led to creation of wrecking worldwide challenges. Such fast transferable pathogens requiring practical diagnostic setups to control their transfer chain and stop sever outbreaks in early stages of their appearance. Herein, we have addressed this urgent demand by designing a rapid electrochemical diagnostic kit composed of fixed/screen printed electrodes that can detect pathogenic viruses such as SARS-CoV-2 and/or animal viruses through the differentiable fingerprint of their viral glycoproteins at different voltage positions. The working electrode of developed sensor is activated upon coating a layer of coupled graphene oxide (GO) with sensitive chemical compounds along with gold nanostars (Au NS) that can detect the trace of viruses in any aquatic biological media (e.g., blood, saliva and oropharyngeal/nasopharyngeal swab) through interaction with active functional groups of their glycoproteins. The method do not require any extraction and/or biomarkers for detection of target viruses and can identify trace of different pathogenic viruses in about 1 min. The nanosensor also demonstrated superior limit of detection (LOD) and sensitivity of 1.68 × 10−22 μg mL−1 and 0.0048 μAμg.mL−1. cm−2, respectively, toward detection of SARS-CoV-2 in biological media, while blind clinical evaluations of 100 suspected samples furtherly confirmed the superior sensitivity/specificity of developed nanosystem toward rapid identification of ill people even at incubation and prodromal periods of illness. Image 1 A nanosensor based on graphene and gold nanostars was developed toward detection of viruses The developed nanosensor detected diverse viruses through their viral glycoproteins The nanosensor showed different fingerprints for each examined virus The nanosensor detected the SARS-CoV-2 with high accuracy and low DL [ABSTRACT FROM AUTHOR]