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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 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.

The analysis of chemically reactive rheological liquids subjected to heat-mass transference has turn out to be more and more influential in chemical engineering, drawing considerable relevance. Such rising relevance is noticeable in diverse utilizations, for illustration food processing techniques, scattering and formation of haze, damage of crop via freezing temperatures, cooling towers and the distribution of moisture together with temperature in both orchards and agricultural fields. This study accounts chemically reactive diffusive-thermo and thermo-diffusive flow of Oldroyd-B material induced by vertically moving surface. Modeling of thermal (energy) and species concentration is based on thermal source, variable conductivity, chemical reaction and variable diffusivity. The non-dimensionalized steady-state model for boundary-layer stretchy flow is obtained by deploying similarity transformations and then built-in maple software based on shooting scheme is implemented for nonlinear computational analysis. Results graphically and arithmetically depict dimensionalized profiles providing realistic insights for engineering utilizations. It is inspected that both thermal and solutal fields increase when varying conductivity and varying diffusivity factors are boosted. Besides, it is noticed that absolute percentage increase for Pr is 17.75 % from 1.3 to 1.1 while a decay of 35 % is observed in Df from 0.2 to 0.1.

This study examines the flow and thermal behavior of a power-law ferrofluid in a differentially heated enclosure containing a rectangular permanent magnet. The novelty of the present study lies in its exploration of the combined effects of magnetic and gravitational convection on the flow and thermal behavior of a power-law ferrofluid in the presence of a permanent magnet with varying aspect ratios. Unlike previous studies, this work specifically investigates how the magnet's aspect ratio, location, and the ferrofluid's rheological properties influence heat transfer, particularly in microgravity environments. Moreover, the study assesses the impact of the temperature number and the magnetic and gravitational Rayleigh numbers on the flow, temperature distribution, and Nusselt number variations. Findings indicate that strong gravitational effects can hinder magnetic convection, whereas, in microgravity conditions, heat transfer is maximized with a thin magnet (aspect ratio 1:9) in the cavity, yielding up to a 94 % increase in the average Nusselt number compared to a square magnet of the same volume. The average Nusselt number can increase up to four times by reducing the power-law index from 1.3 to 0.7, and by about 70 % when the magnet is moved towards the left hot wall compared to its central placement.

Energy-related CO2 emissions are one of the biggest concerns facing urban design today, increasing rapidly as cities grow. This study uses as inputs the GDP of the G8 nations (from 1990 to 2016) depending on the utilization of various energy sources, including coal, oil, natural gas, and renewable energy. Multilayer perceptrons (MLP) are combined with various nature-inspired optimization algorithms, such as Heap-Based Optimizer (HBO), Teaching-Learning-Based Optimization (TLBO), Whale Optimization Algorithm (WOA), Vortex Search algorithm (VS), and Earthworm Optimization Algorithm (EWA), to create a dependable predictive network that takes the complexity of the problem into account. Our key contributions lie in developing and comprehensively evaluating these hybrid models assessing their efficacy in capturing the intricate dynamics of carbon emissions. The study found that TLBO and VS outperform other algorithms in CO2 emission computation accuracy. TLBO has a higher training MSE (3.6778) and lower testing MSE (4.4673), suggesting larger squared errors on training data and lower testing MSE, suggesting less overfitting due to better generalization to the testing set.

Motile microorganisms, such as bacteria, can be engineered to transport medications directly to certain organs, such as cancer, tumors, enhancing drug efficacy and minimizing systemic side effects. These microorganisms can also be programmed to target and eliminate harmful bacteria, offering a novel approach to infection control. In parallel, functionalized nanomaterials show significant promise for precise manipulation of biological fluids. This focused approach improves drug efficacy while reducing systemic negative effects. Also, motile bacteria can be engineered to target and remove dangerous bacteria, providing a fresh approach to infection control. Nanomaterials with various functions show prodigious potential for precise operation of biological fluids. Tetra-hybrid nano-particles exhibit special electrical, optical, and thermal properties. They are composed of gold, silver, alumina, and titania. The streaming flow phenomena that result from the interactions of these nanocomposites with non-Newtonian biofluids, such as blood, can be studied using computational modeling. Considerations are made for forces such as non-Newtonian rheology, localized laser irradiation, and magnetohydrodynamics. Complex cellular trapping patterns are captured by predictions for temperature, velocity, and nanoparticle concentration profiles. Biocompatible multimodal nano-assemblies under magnetic actuation and thermos-plasmonic effects are used to exhibit precision biofluid control. To optimize, engineering parameters are visually analyzed. The unique features of tetra-hybrid nanoparticles, paired with motile microorganisms and non-Newtonian biofluid dynamics, allow for more precise therapeutic techniques, such as targeted medication administration and hyperthermia cancer treatment. By visualizing key engineering parameters, these findings highlight the potential for improved therapeutic strategies, such as targeted drug delivery and hyperthermia-based cancer treatments, enabled by the integration of tetra-hybrid nanoparticles and motile microorganisms in complex biofluid environments.

The first checklist of halictid bees (Hymenoptera: Halictidae) in Tunisia is established based on available data in the literature. This list contains 114 species belonging to four subfamilies (Halictinae Thomson; Nomiinae Robertson; Nomioidinae Börner; Rophitinae Schenck) and nine genera. The genus Lasioglossum Curtis within the subfamily Halictinae is the most diverse with 51 species and subspecies. The highest number of species is reported in the Tunisian south region with 51 species and subspecies. For each species, the global and provincial distribution in Tunisia is given based on the relevant literature. 40 taxa are without specific locality in Tunisia and confirmation of their presence in the country is needed. All reported species from Tunisia are Palaearctic and more than 20% of them have an exclusive north African distribution and among them, five species are endemic to Tunisia. This study is an initiative for further research on local wild bee faunas aiming to suggest their conservation strategies.

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.