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Samar S Mabrouk,1 Ghada R Abdellatif,1 Mona R El-Ansary,2 Khaled M Aboshanab,3 Yasser M Ragab4 1Department of Microbiology, Faculty of Pharmacy, Ahram Canadian University (ACU), 6th of October, Giza, Egypt; 2Department of Biochemistry, Modern University for Technology and Information (MTI), Cairo, Egypt; 3Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University (ASU), Cairo, Egypt; 4Department of Microbiology & Immunology, Faculty of Pharmacy, Cairo University (CU), Cairo, EgyptCorrespondence: Khaled M AboshanabDepartment of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, Organization of African Unity St., PO: 11566, Abbassia, Cairo, EgyptTel +20 225082595Fax +20 224051107Email aboshanab2012@pharma.asu.edu.egPurpose: This study aimed to detect the prevalence of carbapenemase producers (CPs) among extensive drug-resistant (XDR)-carbapenemase producing Gram-negative bacteria (GNB) recovered from various clinical specimens of hospitalized neutrophilic febrile patients in two major tertiary care hospitals in Egypt.Methods: Standard methods were used to evaluate the antimicrobial susceptibility of clinical isolates according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Phenotypic and genotypic analysis of CPs were carried out and statistically analyzed using standard methods.Results: Three hundred and forty-two GNB were obtained from 342 clinical specimens during the period of the study, where 162 (47%) were enterobacterial isolates, including, 63 (18.4%) Escherichia coli, 87 (25.4%) Klebsiella spp., 5 (1.46%) Enterobacter cloacae, 5 (1.46%) Salmonella spp. and 2 (0.6%) Proteus and 180 (53%) were non-fermentative bacilli including, 129 (37.7%), Acinetobacter baumannii, and 51 (14.9%), Pseudomonas spp. Out of the 342 GNB, 188 (54.9%) isolates were multi-drug resistant (MDR). Of these, 52 (27.6%) were XDR as well as CPs as confirmed phenotypically. The MIC of imipenem against the XDR GNB against showed either low (11 isolates; 21.1%; MIC range =4– 32 μg/mL) or high levels of resistance (41 isolates; 78.8%; MIC range = 64-≥ 1024). The most prevalent carbapenem resistance (CR) genes were blaKPC (63.5%) followed by blaOXA-48 (55.7%) and blaVIM (28.8%). No significant association could be observed between the MIC level and the presence of CR genes (P value > 0.05).Conclusion: High prevalence of MDR (54.9%) and XDR (27.6%) GNB pathogens associated with high levels of resistance to carbapenems were observed. All XDR GNB were CPs and tested positive for at least one of the CR genes. However, most of them (78.8%) showed a high level of CR (MIC range = 64-≥ 1024) with no significant association with the CR genes.Keywords: carbapenem resistance, carbapenemases, MDR, XDR, Gram-negative pathogens

Blue rot disease caused by Penicillium expansum is one of the most widespread fungal diseases that affects apples worldwide. This work was to verify the effect of chitosan (2 and 4 g/L) and its nano-form (0.2 and 0.4 g/L) against blue rot disease on apples and their effect on the expression of six defense-related genes as well as fruit quality parameters. Regarding disease incidence, in most cases, chitosan NPs performed better as compared to their raw materials for both artificial and natural infections. The highest efficacy was obtained for chitosan NPs at 0.4 g/L for artificial and natural infection in both 2019 and 2020 seasons. All treatments kept fruit quality parameters regarding firmness, total soluble solids, and titratable acidity for artificial and natural infection in both seasons. As expected, the exogenous application of chitosan NPs and bulk form triggered an increase in the expression levels of six defense-related genes including chitinase, peroxidase, β-1,3-glucanase, Xyloglucan endotransglycosylase (XET), pathogenesis-related protein (PR8), and phenylalanine ammonia lyase-1 (PAL1). Moreover, the highest mRNA quantity of all the studied genes was detected in leaves treated with chitosan NPs at both concentrations compared to other treatments. Chitosan NPs can be considered an eco-friendly and effective approach against blue mold of apples and can be integrated into management programs to maintain postharvest quality and extend the shelf life of fruits.

Nowadays, there is great attention given to solar collectors (SCs) for their important applications based on the advantages of nanotechnology and solar radiation. Hybrid nanofluid (HNF) is our first option due to its thermophysical properties that help in improving the overall performance, unlike other nanofluids. This paper gives a detailed novel analysis of SCs with the existence of Newtonian, power-law HNF in unsteady conditions and a three-dimensional model under the consideration of Brownian motion and thermophoresis parameter. In this research, the group transformation method (GTM) and similarity transformation steady state fluid dynamics are used to transform the mathematical model into a simpler system. This coupled system of ordinary differential equations with the related functions, dimensionless entropy generation and Bejan number is achieved at two cases of power-law index. The impact of involved parameters on velocity profile, temperature distribution, concentration field, entropy output of the system and Bejan number is depicted prominently by various graphs. The fluid velocity shows improvement with higher values of power-law index and shape factor, while it diminishes with magnetic parameter and Prandtl number. Enhancing the values of magnetic field and shape factor, results in increase of temperature characteristic which decreases with Prandtl number and power-law index. Increment in the concentration ratio parameter leads to maximize the entropy generation, whereas entropy generation diminishes with higher values of temperature ratio and magnetic parameter. The obtained results and the previously published work are compared qualitatively and quantitatively to each other to validate that the applied method is more efficient. It is predicted that the Nusselt number improves by 28.18% when the Prandtl number is taken range (4 ≤ Pr ≤ 6). The percentage of increasing in Sherwood number is noted to be 18.61% for range (0. 1 ≤ N b ≤ 0. 5) of Brownian motion parameter. [ABSTRACT FROM AUTHOR]

In this work, the three-dimensional unsteady flow was scrutinized adjacent to a flat plate immersed inside a fluid with electric conductivity in the presence of constant magnetic field. An extended model of group transformation method was exploited, comprising three parameters, to transform the mathematical model into a new system of ordinary differential equations (ODEs). The proposed method is rarely and seldom used in handling higher dimensions coupled equations. Two cases were studied, the stretching and shrinking plate. In the first case, the results showed that both of magnetic parameter, M, and Prandtl number, Pr, affected inversely the fluid velocity, the shear stress and the temperature distribution. On the contrary, the heat flux increased when both M and Pr increase. That could be interpreted by the effect of larger magnetic force and fluid viscosity, respectively. In case of shrinking plate, the attained results were opposite to those of stretching case specially for the effect of magnetic parameter. [ABSTRACT FROM AUTHOR]