17 research outputs found

    Knowledge, Attitude, and Behavior of Egyptian Medical Students Toward the Novel Coronavirus Disease-19: A Cross-Sectional Study

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    BACKGROUND: People in times of pandemics, crave after any medical field member (including medical students) to gain their knowledge and correct their behaviors. AIM: We aimed to assess medical students’ coronavirus disease (COVID)-19 related knowledge, attitude, and behavior (KAB). METHODS: The study is an exploratory cross-sectional study, conducted among medical students using an online survey. Medical students were classified according to their current academic year into either early year’s group (first 3 years in the medical school) or final year’s group (past 3 years in the medical school). RESULTS: A total of 2255 students completed the questionnaire. Regarding their COVID-19 related knowledge; 63.4% gave unsatisfactory responses (answered <75% of the questionnaire items correctly). Most of males (62.9%) and females (64.1%) gave unsatisfactory responses. CONCLUSION: Most of students had unsatisfactory responses of the current pandemic; however, the final year’s group had a significantly higher score in nearly all questionnaire (KAB) subsections than the early year’s group. The majority of both groups significantly believed that there are undeclared numbers in Egypt. Facebook and other platforms were the most common sources of information

    Amelioration of The Dielectric Properties of Ceramic Insulators Using Nano-alumina

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    Outdoor HV porcelain insulators face various environmental stresses that cause their degradation. Consequently, amelioration of their insulating properties becomes a target of recent researches to survive higher voltage levels. Investigating the impact of the addition of 0, 5, 10, and 15 wt. % nano- alumina (NA) on the dielectric and physical characteristics of porcelain materials at elevated sintering temperatures is the aim of this study. Porcelain specimens were synthesized from kaolin, feldspar, and quartz as available low-cost raw materials. The specimens were sintered at 1100, 1200, 1300, and 1400°C for 2 h. For some specimens, the microstructure and phases formed were identified using scanning electron microscopy and X-ray diffraction techniques. The changes that occur upon heating (include melting, phase transition, sublimation, and decomposition) were identified by Differential Thermogravimetric Analysis. The dielectric strength, relative permittivity, and loss tangent of different samples were measured at a large scale of frequencies. Breakdown strength values of different samples were verified by applying the Finite Element Method. The best electrical and physical properties were achieved at 1300ºC. At this temperature the porcelain sample containing 5 wt. % NA presented optimum physical characteristics as well as good insulating properties assent the feasibility of producing electro-technical porcelai

    Cellulosic Fiber Waste Feedstock for Bioethanol Production via Bioreactor-Dependent Fermentation

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    The bioconversion of environmental wastes into energy is gaining much interest in most developing and developed countries. The current study is concerned with the proper exploitation of some industrial wastes. Cellulosic fiber waste was selected as a raw material for producing bioethanol as an alternative energy source. A combination of physical, chemical, and enzymatic hydrolysis treatments was applied to maximize the concentration of glucose that could be fermented with yeast into bioethanol. The results showed that the maximum production of 13.9 mg/mL of glucose was achieved when 5% cellulosic fiber waste was treated with 40% HCl, autoclaved, and followed with enzymatic hydrolysis. Using SEM and FTIR analysis, the instrumental characterization of the waste fiber treatment confirmed the effectiveness of the degradation by turning the long threads of the fibers into small pieces, in addition to the appearance of new functional groups and peak shifting. A potent yeast strain isolated from rotten grapes was identified as Starmerella bacillaris STDF-G4 (accession number OP872748), which was used to ferment the obtained glucose units into bioethanol under optimized conditions. The maximum production of 3.16 mg/mL of bioethanol was recorded when 7% of the yeast strain was anaerobically incubated at 30 °C in a broth culture with the pH adjusted to 5. The optimized conditions were scaled up from flasks to a fermentation bioreactor to maximize the bioethanol concentration. The obtained data showed the ability of the yeast strain to produce 4.13 mg/mL of bioethanol after the first 6 h of incubation and double the amount after 36 h of incubation to reach 8.6 mg/mL, indicating the efficiency of the bioreactor in reducing the time and significantly increasing the product

    Influence of magnetic field on the physicochemical properties of water molecule under growing of cucumber plant in an arid region

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    This study highlights the potential impact of magnetic fields on water quality, which could have implications for plant growth and development. Theoretical estimates of changes in surface tension, pH, and some other properties due to passing water through a magnetic field for a certain period were experimentally validated in this study. Overall, the results revealed changes in the physicochemical properties of water after magnetic field application. In accordance, pH significantly (p < 0.05) increased from 2 to 2.25, from 4 to 4.5, from 6 to 6.45, from 7.3 to 7.8, and from 8 to 8.7 and except at pH10, which decreased from 10 to 9.7. In addition, the model developed in this study indicated that the change of electrical conductivity (EC) decreased from 9 to 6.11 dS m−1 with an increasing number of run flow through the magnetic field. The decline in EC can be described as follows: magnetically treated water contains fine colloidal molecules and electrolytic chemicals that respond to a magnetic field by enhancing their ability for precipitation, resulting in a fall in EC. Moreover, the Hardness values of recirculated water were decreased after magnetic field application. This corroborates the decline of calcium carbonate adhesion and surface tension values as increases in hydrogen bonding between protons and water molecules and changes in the distribution of molecules in magnetized water. As the internal electrical field grew and the hydration shells surrounding the constituent ions weakened, EC decreased. Lastly, by using an electronic microscope, observing the water in regular, such as regular hexagonal tree shape instead of random irregular shapes after magnetic field application, confirming that the magnetic field had a significant effect on the physical properties of water molecules. In conclusion, magnetic behavior may improve water quality, resulting in increased development and plant growth

    Antibacterial Activity of Polygonum plebejum and Euphorbia hirta Against Staphylococcus aureus (MRSA)

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    The agar diffusion method was used to determine the antimicrobial activities of Euphorbia hirta (EH) and Polygonum plebeium (PP) against S.aureus , B39. Ethyl acetate extract of Euphorbia hirta (EH) and Polygonum plebejum (PP),was the most effective solvent. MIC of plant extract Polygonum plebeium (PP) and Euphorbia hirta (EH) was 25mg/ ml. The antimicrobial activity of ethyl acetate extract of E. hirta (EH) and P. plebeium (PP) was more effective when incubated at 25°C for 10 min with MRSA, B39; pH 5 was more effective against MRSA, B39. Light condition for 24hr was effective against MRSA, B39; Static condition had slight effectiveness against MRSA, B39. Xylose exhibited the highest activity on MRSA, B39; no amino acids, metallic ions and vitamins were effective. Ethyl acetate extract of E. hirta (EH) was subjected to column chromatography and monitored with TLC, 5 spots were detected. Anti MRSA spots were identified as Hydroquinone and O-coumaric acid

    Downregulation of interleukin 36γ and its cleaver cathepsin G following treatment with narrow-band ultraviolet B phototherapy in psoriasis vulgaris

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    Background Growing evidence suggests the important role of IL-36 in the pathogenesis of psoriasis. Cathepsin G is a neutrophil-derived protease that can activate IL-36γ. Objective To assess the expression of IL-36γ and cathepsin G in psoriasis and to quantify the impact of treatment with narrow-band ultraviolet B phototherapy (NB-UVB) on their levels. Methods This case-control study involved 26 patients with moderate-severe psoriasis and 25 healthy volunteers. Psoriasis patients eligible for phototherapy received 24 NB-UVB sessions. Punch skin biopsies were obtained from all participants at recruitment and after phototherapy from patients. Real-time PCR was utilized for quantitative assessment of IL-36γ and cathepsin G expression in tissue samples. Results The expression of IL-36γ and cathepsin G was significantly higher in psoriasis before NB-UVB therapy compared to controls (p < .001). Both proteins decreased significantly with clinical improvement following NB-UVB therapy compared to baseline (p < .001). However, their expression after treatment was still higher than controls (p < .001). Conclusion IL-36γ and cathepsin G expression is upregulated in psoriatic lesions, supporting their role as mediators of inflammation in psoriasis. Downregulation of IL-36γ and cathepsin G is a possible mechanism for psoriasis improvement after NB-UVB therapy. IL-36 and cathepsin G can be considered as therapeutic targets for psoriasis

    Preparation and Characterization of Super-Absorbing Gel Formulated from κ-Carrageenan–Potato Peel Starch Blended Polymers

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    κ-carrageenan is useful for its superior gelling, hydrogel, and thickening properties. The purpose of the study was to maximize the hydrogel properties and water-absorbing capacity of κ-carrageenan by blending it with starch from potato peels to be used as safe and biodegradable water-absorbent children’s toys. The prepared materials were analyzed using FTIR and Raman spectroscopy to analyze the functional groups. Results showed that there was a shift in the characteristic peaks of starch and κ-carrageenan, which indicated their proper reaction during blend formation. In addition, samples show a peak at 1220 cm−1 corresponding to the ester sulfate groups, and at 1670 cm−1 due to the carbonyl group contained in D-galactose. SEM micrographs showed the presence of rough surface topology after blending the two polymers, with the appearance of small pores. In addition, the presence of surface cracks indicates the biodegradability of the prepared membranes that would result after enzymatic treatment. These results are supported by surface roughness results that show the surface of the κ-carrageenan/starch membranes became rougher after enzymatic treatment. The hydrophilicity of the prepared membranes was evaluated from contact angle (CA) measurements and the swelling ratio. The swelling ratio of the prepared membranes increased gradually as the starch ratio increased, reaching 150%, while the water-uptake capacity increased from 48 ± 4% for plain κ-carrageenan to 150 ± 5% for 1:2 κ-carrageenan/starch blends. The amylase enzyme showed an effective ability to degrade both the plain κ-carrageenan and κ-carrageenan/starch membranes, and release glucose units for up to 236 and 563, respectively. According to these results, these blends could be effectively used in making safe and biodegradable molded toys with superior water-absorbing capabilities

    Experimental Optimization with the Emphasis on Techno-Economic Analysis of Production and Purification of High Value-Added Bioethanol from Sustainable Corn Stover

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    Bioethanol-derived biomass is a green sustainable source of energy that is highly recommended as an efficient alternative to the replacement of fossil fuels. However, this type of bioethanol production is always expensive with very low bioethanol concentration. Therefore, this work aims to represent a facile and green approach for bioethanol production with high concentration and purity as well as reasonable cost from corn stover (CS). The goal of this study is to characterize CS and its treated samples with maleic acid (CSM) using various characterization analyses, such as proximate and ultimate analysis, HHV, TGA, FTIR, SEM, and CHNS. The bioethanol production stages: Pretreatment, enzymatic degradation, fermentation, and finally bioethanol separation and purification via the pervaporation process, which have been investigated and optimized are associated with the economic analysis. The optimum operating condition of the pretreatment process was 2% maleic acid, 1:20 solid-to-liquid ratio at 45 psi, 120 &deg;C, and 1 h of operation in the autoclave. This process contributes to 53 and 45% lignin and hemicellulose removal, 98% cellulose recovery, and a glucose yield of 741 mg/dL. The yeast isolate succeeded in the production of 1230 mg/dL of bioethanol. This isolated yeast strain was close to Pichia nakasei with a similarity of 98%, and its amplified 18S rRNA gene sequence was deposited in GenBank with the accession number MZ675535. Poly (MMA-co-MA) membrane was synthesized, characterized, and its efficiency for increasing the bioethanol concentration was evaluated using the integrated pervaporation technique. The techno-economic analysis is presented in detail to evaluate the process profitability, which achieves a considerable profit for the whole duration of the project without any losses as it reaches a net profit of USD 1 million in 2023, reaching USD 2.1 million in 2047 for a company with a capacity of 32 thousand tons per year. The sequential strategy offers a promising approach for efficient bioethanol production under mild and environmentally friendly conditions that enable its implication industrially

    Experimental Optimization with the Emphasis on Techno-Economic Analysis of Production and Purification of High Value-Added Bioethanol from Sustainable Corn Stover

    No full text
    Bioethanol-derived biomass is a green sustainable source of energy that is highly recommended as an efficient alternative to the replacement of fossil fuels. However, this type of bioethanol production is always expensive with very low bioethanol concentration. Therefore, this work aims to represent a facile and green approach for bioethanol production with high concentration and purity as well as reasonable cost from corn stover (CS). The goal of this study is to characterize CS and its treated samples with maleic acid (CSM) using various characterization analyses, such as proximate and ultimate analysis, HHV, TGA, FTIR, SEM, and CHNS. The bioethanol production stages: Pretreatment, enzymatic degradation, fermentation, and finally bioethanol separation and purification via the pervaporation process, which have been investigated and optimized are associated with the economic analysis. The optimum operating condition of the pretreatment process was 2% maleic acid, 1:20 solid-to-liquid ratio at 45 psi, 120 °C, and 1 h of operation in the autoclave. This process contributes to 53 and 45% lignin and hemicellulose removal, 98% cellulose recovery, and a glucose yield of 741 mg/dL. The yeast isolate succeeded in the production of 1230 mg/dL of bioethanol. This isolated yeast strain was close to Pichia nakasei with a similarity of 98%, and its amplified 18S rRNA gene sequence was deposited in GenBank with the accession number MZ675535. Poly (MMA-co-MA) membrane was synthesized, characterized, and its efficiency for increasing the bioethanol concentration was evaluated using the integrated pervaporation technique. The techno-economic analysis is presented in detail to evaluate the process profitability, which achieves a considerable profit for the whole duration of the project without any losses as it reaches a net profit of USD 1 million in 2023, reaching USD 2.1 million in 2047 for a company with a capacity of 32 thousand tons per year. The sequential strategy offers a promising approach for efficient bioethanol production under mild and environmentally friendly conditions that enable its implication industrially
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