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Abstract This study investigates free convective within an octagonal cavity, which is partitioned into two compartments by a flexible separator. One of the left walls is maintained at a high temperature, while a lower temperature is applied to one of the right walls. The position of these active walls is adjustable, and the separator can be oriented vertically or inclined with either a positive or negative slope. The deformation of the flexible separator is modeled using the Arbitrary Lagrangian–Eulerian method. The outcomes indicate that locating the hotter wall near the top and moving the colder wall downwards hinders free convection and reduces the stress in the separator. Moreover, upward movement of both active walls leads to a decrease in the average temperature. An inclined separator with a positive slope enhances the heat transfer rate and experiences the lowest stress levels compared to vertical and negatively sloped separators. Raising Rayleigh number enhances the flow intensity and the stress in the flexible separator. Furthermore, it is found that a decrease in the elasticity modules of the separator from 1014 to 5 × 1011 results in a 5% increase in the average Nusselt number.

Background: Quinolone-resistant enterobacterial isolates have spread largely across hospitals and community in last years. In Tunisia, numerous studies describe the emergence of plasmid mediated quinolone resistance (PMQR) genes among Enterobacteriaceae. Objectives: Detection of PMQR genes among a collection of enetrobacterial isolates recovered in the Tahar Sfar University hospital in Tunisia and in the community. Methods: In vitro antimicrobial susceptibility testing, extended-spectrum β-lactamases, and PMQR genes were detected using PCR. Clonality of isolates was assessed by ERIC-PCR. Results: In this work, 1710 enterobacterial isolates were recovered in the Tahar Sfar University Hospital in Tunisia between January 2012 and March 2013. Eighty of them were resistant to nalidixic acid: 61 isolates and 19 isolates were isolated from nosocomial and community cases respectively. Detection of PMQR genes leads to the identification of 7 and 8 QnrB producers in nosocomial and community acquired strains respectively. The qnrS PMQR gene was less present with 5/61 cases in nosocomial starins and 1/19 case in community one. The most predominant ESBL was the CTX-M-type one. According to ERIC-PCR profiles, we note a multiclonal dissemination with 12 different profiles in hospital-acquired strains and 9 profiles in community enterobacterial isolates. Conclusion: This result re-emphasize the widely distribution of the QNRB genes and their role in resistance to fluoroquinolones.

Abstract Variable viscosity, activation energy and microgravity effects on Darcy nanofluid for the thermal performance improvement in thermal energy storage systems through stretching flat plate solar collector is the focus of this research. Thermal energy storage (TES) can be improved though solar collectors, phase change materials and photovoltaic cells using nanofluid in the base liquid. To increase the reaction rate in nanoparticles, the activation energy and solar radiations are used for the efficiency of TES. The viscosity of nanofluid improves the heat and mass transmission. Due to solar radiations, nanofluid plays prominent role in TES applications such as heat exchangers, electronic cooling devices and solar power generation through solar plate collector. Solar energy based mathematical model is developed to execute the frequency of oscillating heat transfer in TES numerically. Primitive and Stokes coefficients are used for feasible programming. Finite difference analysis is performed to display oscillatory thermal energy using Gaussian-elimination matrix scheme. Steady velocity, surface temperature and concentrations are plotted and utilized in oscillatory formula to perform oscillatory skin friction, oscillatory heat transfer and oscillatory mass transfer along π⁄4 angle. Fluid velocity enhances but temperature and concentration variation decreases as viscosity decreases. High amplitude in velocity, temperature and concentration is sketched as activation energy and microgravity increases. Steady heat and mass transmission enhances as thermophoretic and Brownian motion enhances. Amplitude and frequency of oscillations in heat transport, skin friction and mass transport enhances as Prandtl and Schmidt component enhances. In validation of results, the 0.00064% percentage error for heat transport and 0.00102% percentage error for mass transmission are deduced.

In the present advanced technological century, investigation of Joule-heat effects and radiating energy on power-law nanomaterial movement along a vertical extended sheet have presented the substantial potential in numerous engineering and technological applications. In this manuscript, the detailed numerical study of thermal-mass transmission with joule heating and thermal radiation influence on power-law nanofluid flow is presented. The physical problems are converted into a nonlinear ordinary differential equation under the implementation of similarity transformations, stream functions and Keller box method. Utilizing the similarity transformation, thermal energy, mass, and momentum are reduced to an algebraic system. Dimensionless stretching surface functions are impacted by nanofluid parameters such as magnetic parameter, thermophoresis parameter Nt, Nb, joule heating J, thermal radiation Nr, Le, and Pr. These effects are displayed numerically and graphically. With the use of MATLAB and Keller box method, the quantitative connection of skin friction and heat transport is demonstrated. The values of skin friction coefficient Cf, Sherwood number Shx and Nusselt number Nux are calculated in tables and compared with publish results for good harmony. It is found that higher value of joule factor enhances maximum heat-rate in fluid at n = 0.3.

Indeed, nanoliquids have acquired substantial consideration in heat transference field because of their inimitable thermal attributes and favorable application likelihoods. In contrast to orthodox liquids, the haphazard movement of nanoparticles within nanoliquid strengthens fluid turbulence, accomplishes superior thermal effectiveness and declines thermal resistance. Nanoliquids have ample utilization, for illustration, solar energy, electronic chips, automotive radiators and heat exchangers etc. This communication reports chemically reactive electro-magnetized nanomaterial dissipative flow confined by rotating cone. Flow expressions include thermo-solutal buoyancy, varying viscosity and magneto-hydrodynamics. Radiative heat, thermophoresis, viscous dissipation, Brownian diffusion, thermal source and first order chemical reaction are pondered to model transport expressions. Relevant variables are introduced to transfigure partial differential mathematical expressions to mathematical ordinary ones. Numerical outcomes for non-dimensional mathematical expressions are reported via bvp4c algorithm in MATLAB. The comprehensive results featuring dimensionless quantities are explored through graphs and arithmetic representations. It is evaluated that escalating values of variable viscosity, Prandtl number and unsteady parameter decline temperature but temperature is improved as a consequence of progressive variation in radiation parameter, Eckert number, thermophoresis parameter, heat generating and Brownian diffusive variables. The study is relevant to cooling industry, electroconductive, thermal collector and nano-materials processing.

Abstract Alzheimer's disease (AD) is an age‐related neurodegenerative pathology. Brain‐derived extracellular vesicles (EVs) have been demonstrated to be implicated in AD pathogenesis by facilitating the propagation of Tau, amyloid‐β and inflammatory cytokines. However, the impact of peripheral EVs (pEVs) in AD pathogenesis remains poorly investigated. The objective of our study was to compare the passage of pEVs from adults, cognitively healthy elderly, and AD patients through the blood‐brain barrier (BBB), to evaluate their uptake in the brain and to assess their impact on the microglia activity using in vitro and in vivo models. To this end, pEVs were enriched, characterized, and fluorescently labelled. The passage of pEVs through the endothelial bEnd.3 cells was studied in a Transwell device with either neuronal or microglia cells seeded at the bottom of the well. Following the internalization of pEVs from AD patients, microglia adopted an amoeboid morphology and released a heightened level of pro‐inflammatory cytokine IL‐6. To further assess their in vivo transport across the BBB, pEVs were injected into the blood circulation of 2‐days post‐fertilization Tg(flk1:EGFP) zebrafish. The biodistribution of pEVs was monitored at 1 and 24 h post‐injection using confocal microscopy. We demonstrated that pEVs traverse the BBB by transcytosis and subsequently diffuse progressively into the brain. pEVs were then internalized by neuronal and radial glial cells as seen in Tg(huc:EGFP) and Tg(gfap:EGFP) zebrafish, respectively. Additional experiments were performed with the intrahippocampal injection of pEVs in the mouse, indicating their spreading throughout the brain and their uptake by neuronal and glial cells. These findings contribute to novel insights into the fate of pEVs following their passage through the BBB in vitro and in vivo, and demonstrate for the first time that pEVs from AD patients affect microglia activity. This suggests a potential mechanism through which peripheral tissue cues may contribute to AD pathogenesis.

IntroductionHydroponic cultivation systems using desalinated groundwater may play pivotal role in reducing freshwater consumption for irrigation. However, reliance on desalination remains unsustainable due to its high cost, energy demand, and the serious environmental impacts of its brine byproducts. Producing a biofertilizer that enables groundwater irrigation in hydroponics by enhancing plant halotolerance and resistance to salt stress offers a promising solution to address freshwater scarcity and low soil quality in arid and semi-arid regions, such as the Arabian Gulf.MethodsThis study investigates the potential of Bacillus spizizenii FMH45 in field experiment to enhance tomato plant production under greenhouse cultivation in hydroponics using directly groundwater for irrigation without desalination.Results and discussionResults demonstrated that the FMH45-based biofertilizer (HB45) significantly improved plant physiological parameters under greenhouse conditions. These improvements included a notable increase in shoot elongation (>13%), enhanced SPAD index values (>8%), and significant rises in flower and fruit counts (≃ 11% and 22%, respectively). B. spizizenii HB45 showed significant potential to increase bacterial densities by over 100-fold in various plant organs under saline irrigation and prevent salt infiltration into internal plant tissues. Furthermore, HB45-treatment enhanced the plant oxidative stress response as evidenced by stable catalase activity, an approximately 50% reduction in lipid peroxidation markers such as malondialdehyde (MDA), and a 35% decrease in reactive oxygen species (ROS), including hydrogen peroxide (H2O2). These findings demonstrate that B. spizizenii FMH45 holds significant potential for the development of effective biofertilizers capable of mitigating salt stress while boosting crop productivity. This approach offers a sustainable alternative to desalination-dependent hydroponics, particularly for arid and semi-arid regions, including Qatar.