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The current work aimed to improve the combustion behavior of a non-premixed twin-jet inlet. The effect of fuel and air inlet shape under different velocities was studied using ANSYS as the process takes place in species transport and finite rate/eddy dissipation, and the flow is considered to be turbulent. Two different shapes (circular-circular and circular-elliptic inlet jets) were investigated, and the results show that the behavior and intensity of the fire are affected by variations in the speed and, geometry of the inlet which affects temperature, heat release rate, combustion efficiency, and equivalent ratios. The optimum air/fuel velocities were found to be 2.5/1.5 with circular-circular inlet jets.
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As a progressive neuropathic condition, glaucoma can cause lifelong blindness if left untreated. Novel phenylpyridazine-tethered sulfonamides were designed as selective inhibitors for carbonic anhydrase (CA) isoform II to find effective therapeutic agents for glaucoma. Subsequently, the target inhibitors were synthesized and assessed for their inhibitory action against cytosolic CA I and II. Interestingly, the synthesized molecules poorly inhibited CA I while exhibiting low subnanomolar potency against CA II. Compound 7c disclosed the most potent activity (IC50 = 0.63 nM) with high selectivity against CA II (605-fold than acetazolamide selectivity). Moreover, compound 7c also showed significant in vivo IOP-reducing properties in the in vivo model of glaucoma. Furthermore, the binding of compound 7c to CA II was assessed at the molecular level, exploiting the molecular docking approach.
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Glaucoma , Sulfonamidas , Humanos , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Sulfonamidas/química , Anidrase Carbônica II , Inibidores da Anidrase Carbônica/farmacologia , Inibidores da Anidrase Carbônica/uso terapêutico , Inibidores da Anidrase Carbônica/química , Estrutura Molecular , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Glaucoma/tratamento farmacológico , Sulfanilamida , Anidrase Carbônica IX/metabolismoRESUMO
The current study proposes a new strategy for using small hydroelectric turbines in downstream river branches with the least amount of construction and the lowest cost by comparing two different methods of installing the turbines, the first by installing the turbines at the river's bottom and the second by installing the turbines on floating boats. The methodology of this article is based on predicting the distribution of velocities through the watercourse using experimental data collected at various points in the river's depth, and then predicting the resulting electrical power for different sizes of turbines, as well as estimating the number of turbines for each row and the number of rows along the river. Therefore, Investigate the proposed systems. The proposed small hydropower system's economic viability and environmental impact are investigated in this article. According to the nature of the waterway, the best diameter of a turbine that can be used is 1.5 m based on water velocities and river depths. The proposed power plant generated 25.8 kW per single turbine row, with an estimated cost of produced power (0.035 USD/kWh) of approximately 20 turbines installed per row. Compared to other renewable energy sources, the proposed hydropower system is cost-effective and environmentally friendly, as generating electricity with the proposed small hydropower plant could reduce annual carbon dioxide emissions by 368 tones of CO2 per single turbine row.
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Gravitational energy storage systems are among the proper methods that can be used with renewable energy. However, these systems are highly affected by their design parameters. This paper presents a novel investigation of different design features of gravity energy storage systems. A theoretical model was developed using MATLAB SIMULINK to simulate the performance of the gravitational energy storage system while changing its design parameters. A parametric optimization study was also conducted using Taguchi and analysis of variance (ANOVA) techniques for optimizing the energy storage rate. Six parameters were studied; three are related to the piston design (diameter, height, and material density). The other parameters are the return pipe diameter, length, and charging/discharging time. Results revealed that the piston diameter and height are the two most significant parameters for the system performance compared to the other parameters, as they contributed by 35.11% and 30.28%, respectively. The optimization results indicated that the optimal piston diameter, height, and return pipe diameter were 0.25, 0.5, and 0.01 of the container height. The outcomes of this paper can significantly improve energy storage and power generation from renewable energy systems as it provides a reliable, economical, sustainable, and durable energy storage system.
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Most recently, the whole world is struggling against the virulent pandemic COVID-19. Due to the unbounded global spread of the disease, having biosensors with high performance such as high sensitivity and accuracy is of utmost importance. In this paper, the effects of various parameters on the behaviors of micro-biosensors are investigated in order to enhance their performance. These parameters are related to the geometry and material, and they are assumed to be gradually changing in the longitudinal direction of the biosensor according to a power law. Therefore, they are called functionally graded geometrical and material parameters. Another aspect is when considering microcantilever-based biosensors, the main behavior parameter is the deflection at the free end. In the analyses, the influences of the surface stress and van der Waals intermolecular forces are taken into account. Also, the total energy of the beam, which is the combination of the van der Waals energy and the elastic strain energy, is accomplished. In addition, the equivalent force causing the deflection is also evaluated using Castigliano method for two cases. These cases account for a concentrated force at the free end and a distributed load along the biosensor, respectively. Since the governing equations account for the size dependency and the considered parameters are functions of the position, the solution is too complex to be achieved analytically, and therefore, numerical methods are applied. For uniform biosensors made of homogeneous materials, or in other words when all parameters are not varying with the position, the obtained results are compared with those in the literature, and good agreement is obtained. On the other hand, the performance, which include sensitivity and limit of detection, of functionally graded biosensors can be enhanced by proper choices of the considered parameters and the corresponding exponent of the gradation function.
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Many cancer survivors suffer from chemotherapy-induced cognitive impairment known as 'Chemobrain'. Doxorubicin -topoisomerase II inhibitor- is widely used in breast cancer, hematological cancers and other neoplasms. However, it is reported to precipitate cognitive impairment in cancer patients via inducing oxidative stress and inflammatory response. Chrysin -5,7 dihydroxyflavone- has promising antioxidant, anti-inflammatory and anticancer properties, but suffers low bioavailability owing to its poor solubility and extensive metabolism. In the present study, chrysin was successfully formulated as transfersomal lipid vesicles and chitosan composite vesicles (CCV) exhibiting a nanometric size range, high drug entrapment efficiency, and controlled release over a 72h period. Intranasal administration of optimized chrysin formulations at a reduced dose of 0.5 mg/kg improved doxorubicin-induced memory impairment in rats evidenced by behavioral testing, inhibition of acetylcholinesterase activity and oxidative stress markers; catalase, reduced glutathione, lipid peroxidation and hydrogen peroxide. This could reduce caspase-3 expression inhibiting apoptosis. Moreover, chrysin formulations were able to inhibit doxorubicin-induced Tol-like receptor 4 (TLR4) and p65 subunit of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) protein expression which in turn, reduced procaspase-1, Cysteinyl Aspartate Protease-1 (caspase-1) and Interleukin-1ß (IL-1ß) protein expression via inhibiting Nod-like receptor pyrin containing 3 (NLRP3) inflammasome. Collectively, our findings suggest the enhanced therapeutic potential of chrysin when formulated as transfersomes and CCV against chemotherapy-induced chemobrain via hindering acetylcholinesterase, oxidative stress and TLR4-NF-kB(p65)-NLRP3 pathways.
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Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/toxicidade , Encéfalo/efeitos dos fármacos , Disfunção Cognitiva/induzido quimicamente , Doxorrubicina/administração & dosagem , Doxorrubicina/toxicidade , Flavonoides/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Administração Intranasal , Animais , Antioxidantes/farmacologia , Quitosana , Disfunção Cognitiva/psicologia , Portadores de Fármacos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Flavonoides/farmacologia , Masculino , NF-kappa B/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptor 4 Toll-Like/efeitos dos fármacosRESUMO
OBJECTIVE: To assess the impact of a cervical traction maneuver (Amr's maneuver) used in conjunction with active management of the third stage of labor (AMTSL) on the incidence of postpartum hemorrhage (PPH). METHOD: The present multicenter randomized controlled trial was conducted in Cairo between March 1, 2016, and June 30, 2017. Women aged at least 18 years who had singleton pregnancies and were candidates for vaginal delivery were enrolled. After block randomization, AMTSL was performed for all participants. Following placental delivery, Amr's maneuver using cervical traction for 90 seconds was carried out in the study group. The primary outcome, incidence of PPH (>500 mL blood loss) within 6 hours of delivery, was compared between the study and control groups in an intention-to-treat analysis. RESULTS: There were 852 patients randomized to the study (n=426) and control (n=426) groups. The incidence of PPH was significantly lower in the study group compared with the control group (6 [1.4%] vs 19 [4.5%]; P=0.015). Absolute risk reduction of 3.1% (95% CI 0.8-5.6), relative risk reduction of 0.32 (95% CI 0.13-0.78), and number needed to treat of 33 (95% CI 129-18) were observed in the study group. CONCLUSION: Amr's maneuver was effective in decreasing the incidence of PPH. ClinicalTrials.gov Identifier: NCT02660567.
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Colo do Útero , Parto Obstétrico/métodos , Hemorragia Pós-Parto/epidemiologia , Adulto , Feminino , Humanos , Incidência , Terceira Fase do Trabalho de Parto , Hemorragia Pós-Parto/prevenção & controle , Gravidez , Adulto JovemRESUMO
A new pentacyclic triterpenoid, 3ß,25-epoxy-3α,22ß,23α-trihydroxy-olean-12-en-28-oic acid (1), together with seven known compounds, including five triterpenoids, ß-amyrin (2), lantadene B (3), lantanilic acid (4), lantanolic acid (5) and ursolic acid (6) in addition to ß-sitosterol (7) and benzoic acid (8) has been isolated from the leaves of Lantana montevidensis. Their chemical structures were elucidated by spectroscopic analysis and by comparison with the literature data and/or authentic samples. Compound 1 showed moderate to weak antibacterial activity against Staphylococcus aureus and Escherichia coli.