The most critical attribute of a power control strategy for a fuel cell (FC) and ultracapacitor (UC) based hybrid vehicular power system is the sharing of load demand between available power sources. ...Transients and rapid changes of the power demand may cause drying of the FC membrane resulting in degradation of FC lifetime. The load demand profile of a hybrid electric vehicle (HEV) is a nonstationary fluctuating signal and consists of transients. Wavelet transforms are suitable for analyzing and evaluating such signals for dynamic systems. This paper focuses on the integration of a developed novel-wavelet-based load sharing algorithm and dynamic model of the FC/UC hybrid vehicular power system in order to ensure efficient power flow control strategy.
The available power generated from a fuel cell (FC) power plant may not be sufficient to meet sustained load demands, especially during peak demand or transient events encountered in stationary power ...plant applications. An ultracapacitor (UC) bank can supply a large burst of power, but it cannot store a significant amount of energy. The combined use of FC and UC has the potential for better energy efficiency, reducing the cost of FC technology, and improved fuel usage. In this paper, we present an FC that operates in parallel with a UC bank. A new dynamic model and design methodology for an FCand UC-based energy source for stand-alone residential applications has been developed. Simulation results are presented using MATLAB, Simulink, and SimPowerSystems environments based on the mathematical and dynamic electrical models developed for the proposed system
Thirteen new 2-pyrazoline derivatives bearing benzenesulfonamide moiety (
2a–
m) were synthesized by condensing appropriate chalcones with 4-hydrazinonbenzenesulfonamide hydrochloride and tested for ...anticancer and anti-inflammatory actions. According to the protocol of the National Cancer Institute (NCI) in vitro disease-oriented human cells screening panel assay compounds
2b,
2c,
2e,
2f and
2g exhibited considerable antitumor activities against the entire tested tumor cell lines and showed effective growth inhibition GI
50 (MG-MID) values of 2.63, 2.57, 6.61, 3.31 and 2.57
μM, respectively, beside a cyclostatic activity TGI (MG-MID) 9.54, 8.51, 24.0, 19.9 and 8.71
μM, respectively. Two compounds
2g and
2k showed more potent anti-inflammatory activity than celecoxib at 5
h in carrageenan-induced rat paw edema bioassay. These compounds (
2g and
2k) proved to have superior gastrointestinal safety profiles as compared to celecoxib, when tested for their ulcerogenic effects. Compounds
2g and
2k showed no inhibition against the enzymatic activity of bovine COX-2 (in vitro).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper focuses on the combination of wind turbine (WT), photovoltaic (PV), fuel cell (FC) and ultra-capacitor (UC) systems for grid-independent applications. The dynamic behavior of the proposed ...hybrid system is tested under various wind speed, solar radiation and load demand conditions. The developed model and its control strategy exhibit excellent performance for the simulation of a complete day. In the simulation, the solar radiation and power demand data are based on real world measurements, while the wind speed data are quasi-real because it is simulated based on special wind speed generation algorithms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has evolved into eight fundamental clades with four of these clades (G, GH, GR, and GV) globally prevalent in 2020. To explain plausible ...epistatic effects of the signature co‐occurring mutations of these circulating clades on viral replication and transmission fitness, we proposed a hypothetical model using in silico approach. Molecular docking and dynamics analyses showed the higher infectiousness of a spike mutant through more favorable binding of G614 with the elastase‐2. RdRp mutation p.P323L significantly increased genome‐wide mutations (p < 0.0001), allowing for more flexible RdRp (mutated)‐NSP8 interaction that may accelerate replication. Superior RNA stability and structural variation at NSP3:C241T might impact protein, RNA interactions, or both. Another silent 5′‐UTR:C241T mutation might affect translational efficiency and viral packaging. These four G‐clade‐featured co‐occurring mutations might increase viral replication. Sentinel GH‐clade ORF3a:p.Q57H variants constricted the ion‐channel through intertransmembrane–domain interaction of cysteine(C81)‐histidine(H57). The GR‐clade N:p.RG203‐204KR would stabilize RNA interaction by a more flexible and hypo‐phosphorylated SR‐rich region. GV‐clade viruses seemingly gained the evolutionary advantage of the confounding factors; nevertheless, N:p.A220V might modulate RNA binding with no phenotypic effect. Our hypothetical model needs further retrospective and prospective studies to understand detailed molecular events and their relationship to the fitness of SARS‐CoV‐2.
Highlights
Most dominant spike mutation favors elastase‐2 binding.
The polymerase mutant (P323L) virus may speed up replication that corresponds to higher mutations.
ORF3a viroporin substitution (Q57H) decreases ion permeability.
N protein mutation (RG203‐204KR) can increase nucleocapsid stability and help evade immunity.
Co‐occurring mutations might modulate viral replication and transmission fitness through epistasis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Arsenotrophic bacteria play an essential role in lowering arsenic contamination by converting toxic arsenite As (III) to less toxic and less bio-accumulative arsenate As (V). The current study ...focused on the qualitative and electrocatalytic detection of the arsenite oxidation potential of an arsenite-oxidizing bacteria A. xylosoxidans BHW-15 (retrieved from As-contaminated tube well water), which could significantly contribute to arsenic detoxification, accumulation, and immobilization while also providing a scientific foundation for future electrochemical sensor development. The minimum inhibitory concentration (MIC) value for the bacteria was 15 mM As (III). Scanning Electron Microscopy (SEM) investigation validated its intracellular As uptake capacity and demonstrated a substantial association with the MIC value. During the stationary phase, the strain's As (III) transformation efficiency was 0.0224 mM/h. Molecular analysis by real-time qPCR showed arsenite oxidase (aioA) gene expression increased 1.6-fold in the presence of As (III) compared to the untreated cells. The immobilized whole-cell also showed As (III) conversion up to 18 days. To analyze the electrochemical oxidation in water, we developed a modified GCE/P-Arg/ErGO-AuNPs electrode, which successfully sensed and quantified conversion of As (III) into As (V) by accepting electrons; implying a functional As oxidase enzyme activity in the cells. To the best of our knowledge, this is the first report on the electrochemical observation of the As-transformation mechanism with Achromobacter sp. Furthermore, the current work highlighted that our isolate might be employed as a promising candidate for arsenic bioremediation, and information acquired from this study may be helpful to open a new window for the development of a cost-effective, eco-friendly biosensor for arsenic species detection in the future.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The novel coronavirus, SARS‐CoV‐2, has caused the most unfathomable pandemic in the history of humankind. Bangladesh is also a victim of this critical situation. To investigate the genomic features ...of the pathogen from Bangladesh, the first complete genome of the virus has very recently been published. Therefore, long‐awaited questions regarding the possible origin and typing of the strain(s) can now be answered. Here, we endeavor to mainly discuss the published reports or online‐accessed data (results) regarding those issues and present a comprehensive picture of the typing of the virus alongside the probable origin of the subclade containing the Bangladeshi strain. Our observation suggested that this strain might have originated from the United Kingdom or the other European countries epidemiologically linked to the United Kingdom. According to different genotyping classification schemes, this strain belongs to the A2a clade under the G major clade, is of B and/or L type, and is a SARS‐CoV‐2a substrain. In the future, randomized genomic data will certainly increase in Bangladesh, however because of globalization and immigrant movement, we urgently need a mass regional sequencing approach targeting the partial or complete genome that can link the epidemiological data and may help in further clinical intervention.
Highlights
This commentary has comprehensively explained the genotyping and possible origin of first Bangladeshi SARS‐CoV‐2 strain, which will also help in identifying the similar strains sequenced in future. Moreover, we stress onto the importance of a broad scale, rationale and nation‐wide genomic data analysis correlated with the clinical data.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
NADPH oxidase (Nox), a major source of reactive oxygen species (ROS), is involved in neurodegeneration after injury and disease. Nox is expressed in both neuronal and non-neuronal cells and ...contributes to an elevated ROS level after injury. Contrary to the well-known damaging effect of Nox-derived ROS in neurodegeneration, recently a physiological role of Nox in nervous system development including neurogenesis, neuronal polarity, and axonal growth has been revealed. Here, we tested a role for neuronal Nox in neurite regeneration following mechanical transection in cultured Aplysia bag cell neurons. Using a novel hydrogen peroxide (H
O
)-sensing dye, 5'-(p-borophenyl)-2'-pyridylthiazole pinacol ester (BPPT), we found that H
O
levels are elevated in regenerating growth cones following injury. Redistribution of Nox2 and p40
in the growth cone central domain suggests Nox2 activation after injury. Inhibiting Nox with the pan-Nox inhibitor celastrol reduced neurite regeneration rate. Pharmacological inhibition of Nox is correlated with reduced activation of Src2 tyrosine kinase and F-actin content in the growth cone. Taken together, these findings suggest that Nox-derived ROS regulate neurite regeneration following injury through Src2-mediated regulation of actin organization in Aplysia growth cones.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Recently, an analytical solution of a quadratic nonlinear oscillator has been presented based on the harmonic balance method. By introducing a small parameter, a set of nonlinear algebraic equations ...have been solved which usually appear among unknown coefficients of several harmonic terms. But the method is not suitable for all quadratic oscillators. Earlier, introducing a small parameter to the frequency series, Cheung et al. modified the Lindstedt–Poincare method and used it to solve strong nonlinear oscillators including a quadratic oscillator. But due to some limitations of both parameters, a changed form of frequency-related parameter (introduced by Cheung et al.) has been presented for solving various quadratic oscillators.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Crosslinked hydrogels were developed by in-situ reaction of periodate oxidized pectin (OP) and gelatin. The reaction takes place through the formation of Schiff bases between aldehyde groups of OP ...and amino groups of gelatin. The effect of various process parameters such as reaction time, reaction temperature, pH of the reaction and composition on the efficacy of the crosslinking was investigated. Field emission scanning electron micrsocopy (FESEM) revealed that homogenous, single phase systems are obtained after the crosslinking of OP and gelatin. The swelling characteristics of the hydrogels were monitored. The equilibrium swelling varies in the range of 195-324% with a variation in the gelatin content (10-40%). Glycerol, when used as a plasticizer, improved the flexibility and the handling characteristics of the crosslinked hydrogels. Plasticized films retained good tensile strengths in the range of 19-48 MPa. By proper selection of the reaction conditions, the efficiency of crosslinking can be controlled to obtain the optimum results.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK