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The purpose of this study is to analyze the free convection phenomena arising from a temperature disparity between a cold circular cylinder and a heated corrugated cylinder.

Numerical simulations were used to analyze the convection patterns. The inner cylinder, made of a thermally conductive solid material, was heated through its inner surface, while the space between the cylinders was filled with air. The governing equations for velocity, pressure and temperature were solved using a Galerkin finite element method-based solver for partial differential equations.

The study explored various parameters affecting the dynamic and thermal structure of the flow, including the Rayleigh number (10³ ≤ Ra ≤ 10⁶), the number of corrugations of the inner cylinder (3 ≤ N ≤ 18), the thermal conductivity of the hollow cylinder (1 ≤ K ≤ 200) and the angle of inclination of the inner cylinder (0° ≤ φ ≤ 90°). Results indicated a notable sensitivity of flow intensity to changes in the Rayleigh number and the inner cylinder’s inclination angle φ. Particularly, for Ra = 10⁶, the average heat transfer rate increased by 203% with a K ratio increment from 1 to 100 but decreased by 16.3% as the number of corrugations increased from 3 to 18.

This research contributes to understanding the complex interplay between geometry, thermal properties and flow dynamics in natural convection systems involving cylindrical geometries. The findings offer useful insights for improving the transfer of heat procedures in real-world situations.

This paper aims to the relationship between environmental, social and governance (ESG) ratings and the investment performance of mutual funds with significant exposure to the technology sector. It aims to explore whether ESG-aligned funds deliver superior financial performance, particularly in terms of risk-adjusted returns and if these funds demonstrate better market timing abilities compared to their lower-rated counterparts.

The analysis covers a 10-year period from January 2013 to December 2022, focusing on Eurozone-based mutual funds with more than 40% of their assets under management (AUM) invested in technology firms. The sample includes 912 funds, categorized by their ESG ratings (AAA to CCC), using MSCI ratings as the classification metric. The performance evaluation uses risk-adjusted measures such as the Sharpe ratio, Sortino ratio and Jensen’s alpha, along with an assessment of market timing capabilities based on an extended four-factor model.

The results show that mutual funds with higher ESG ratings consistently outperform their lower-rated peers in both absolute and risk-adjusted returns. These funds also exhibit superior market timing abilities. ESG-aligned funds not only provide a favorable risk-return profile but also enhance the appeal of responsible investment strategies, particularly within the volatile and innovation-driven technology sector. The study reinforces the notion that ESG factors contribute positively to long-term value creation for investors.

The findings are valuable for investors and policymakers aiming to incorporate ESG factors into investment strategies, especially in sectors characterized by rapid technological advancements. The superior performance of ESG-compliant funds highlights the importance of sustainable investing and its potential to align financial returns with broader environmental and social goals.

This study adds to the growing body of literature on ESG investing by specifically focusing on tech-heavy mutual funds in the Eurozone. It offers new insights into how ESG ratings at the fund level, rather than at the firm level, influence investment performance and market timing within the high-growth, high-risk technology sector.

The purpose of this article is to investigate on changes of the microbial load and the chemical and physical properties of date fruits stored for 6 months under two different temperatures.

A composite sample of 100 kg date fruits from the Khalas variety, season 2019, was collected from the local market in Al Ahsa Province, Saudi Arabia, packaged in 1 kg lots, stored at room and refrigerator temperatures and the microbial contamination and the chemical and physical properties monitored over a period of six months of storage. Total bacteria, lactic acid bacteria, Enterobacteriaceae, yeasts and molds were counted and representatives of yeast and mold contaminants were identified using morphological, physiological and molecular typing techniques. Changes in the color and texture of the samples were also monitored during storage.

The yeasts detected were two strains of each of Lachancea thermotolerans and Rhodosporidiobolus fluvialis and one strain of Cystofilobasidium lacus-mascardii. For molds, one strain of each of Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum and Aspergillus caespitosus have been detected. No significant growth of these microorganisms was observed, but enough load persisted during storage that makes the samples not meeting the microbiological standards. There were significant changes in the color and texture of the fruits during storage.

These findings add important information that can help producers and processors to improve quality and promote marketing of date fruits, especially to international markets.

This paper aims to examine the nexus among cloud-based accounting (CBA), employee job performance (EJP) and operational performance (OPP) in the circumstances of Vietnam, an emerging nation. In which the authors examine EJP as a mediator variable inside the research model. Furthermore, the employee digital skills (EDS) factor is examined as a moderating variable for the CBA-EJP nexus and the CBA-OPP nexus, respectively.

The study’s sample was acquired through extensive screening methods. This study used email surveys to acquire data. The survey was sent to 1,200 chief financial officers of Vietnamese firms. For analysis, the ending pattern of 401 e-surveys was used.

By using partial least squares structural equation modeling, the results imply that the CBA has a favorable effect on EJP and OPP. Furthermore, EJP favorably mediates the linkage between CBA and OPP, whereas EDS play a significant moderator role in the CBA-EJP nexus and CBA-OPP nexus, respectively.

This study highlights the crucial role of human factors (i.e. EDS and EJP) for the internal modern applying behaviors (i.e. CBA) and firm value (i.e. OPP) of firms in emerging markets. Therefore, managers should scrutinize the performance of human factors in an essential interval to improve modern applied behaviors and make them more powerful, thus improving the OPP of their firms. Substantially, firm managers should focus on employing the EDS, which enhances the CBA-EJP nexus and the CBA-OPP nexus, respectively.

This study enlarges the OPP documentation by detailing the beneficial effects of human factors as well as the CBA. Furthermore, the study recognizes the effectiveness of EDS as a moderator variable in the context of developing economies. Finally, this work has been regarded as earlier empirical research that integrates all of the aforementioned components into a single model in emerging economies, particularly Vietnam.

This study aims to investigate experimentally and numerically the thermal analysis of a wavy diverging-converging corrugated enclosure, partitioned into two parts under the effect of magnetohydrodynamic (MHD) natural convection. The left part was filled with Al₂O₃/C₂H₆O₂ nanofluid, while the right part was Al₂O₃/C₂H₆O₂ saturated by a porous medium, featuring a corrugated cylinder at the center. This system is relevant to many engineering applications. Key factors affecting thermal performance, such as nanofluid volume fraction, Darcy number, Hartmann number, inclination angle of MHD and Rayleigh number, were analyzed. This study evaluated the impact of these parameters on stream function, average Nusselt number and isothermal lines under three heat source scenarios: heating the corrugated cylinder, heating the magnetic source and heating the nanofluid, porous media and corrugated walls.

The main governing equations for the nanofluid flow are mass, momentum and heat transfer, while the porous media are modeled using the Darcy–Brinkmann model. These governing equations are transformed into a dimensionless form and solved numerically using COMSOL 6.0 based on the finite-element method. Dynamic viscosity, density and thermal conductivity equations are used to calculate the properties of the nanofluid at different volume concentrations.

The results showed that increasing the Rayleigh number (Ra) and Darcy number (Da) increased the Nusselt number by 55%, indicating enhanced heat transfer. A vertical magnetic source (γ = 90°) further improved thermal performance. Conversely, thermal performance decreased with increasing Hartmann number (Ha). The highest Nusselt number was observed when the heat source was applied to the corrugated cylinder, followed by the right side with nanofluid–porous contact and was lowest for the left side with nanofluid contact. Experimental data demonstrated that the presence of a magnetic field can significantly increase the temperature, thereby enhancing heat transfer by natural convection, particularly when the heat source is applied in the region of nanofluid–porous contact.

The primary originality of this work lies in the use of a novel design featuring a diverging-converging structure with a wavy wall. In addition, it uses two types of fluids simultaneously, dividing the enclosure into two sections: the right side contains nanofluid mixed with a porous medium, while the left side is filled with nanofluid only. The system also includes a corrugated cylinder at its center with four undulations. The position of the heat source significantly influences heat dissipation. Therefore, three different positions were examined: heating the cylinder at a constant temperature, heating the left side of the enclosure and heating the right side.

This paper aims to examine the connection between digital payments, ownership structure, and bank performance in Jordan, as well as investigate the moderating role of the independent director in the said relationship.

The study uses data from 12 Amman stock exchange-listed commercial banks, covering the period from 2010 to 2023. This paper employs econometric analysis of panel data, including ordinary least squares (OLS) regression as the primary approach, as well as the generalised method of moments, the two-stage least square (2SLS), and the dynamic model to deal with causality and endogeneity issues in the proposed equations. This ensures that the results are valid.

The results indicate that digital payments and ownership structure have a significant positive connection with bank performance. Additionally, the independent director variable appears to play a substantial and positive moderating role in the link between ownership structure (e.g. institutional ownership) and bank performance. These results strengthen and support the claims of agency theory and the information systems success model.

Overall, this research helps stakeholders, bankers, managers, investors, customers, and policymakers, identify the influence of digital payment and ownership structure on bank performance in developing economies such as that of Jordan.

This investigation offers a unique understanding by illuminating how digital payment and ownership structure affect bank performance in a developing country such as Jordan. Additionally, it opens avenues for future research to delve into this literature domain in North African and Middle Eastern nations, with a particular focus on Jordan. This investigation is among the initial explorations in Jordan that aim to elucidate these relationships. On the theoretical level, it adds to the agency theory and IS model. It provides new insights into the dynamics of industry banking in developing nations (i.e. Jordan).

The study aims to find out the impact of financial inclusion and financial development on financial stability using panel data from eight countries in the Middle East and North Africa (MENA).

To achieve the aim of the study, the researcher prepared two indicators of financial inclusion and governance to find out the impact of financial development on the relationship between financial inclusion and financial stability. Data on financial inclusion was obtained from the International Monetary Fund, data on financial development and financial stability were obtained from the World Bank.

The results of the fixed and random effect methods show that financial inclusion has a significant positive effect on financial stability. Additionally, financial development represents a moderating variable in the significant positive effect on the relationship between financial inclusion and stability in the MENA countries.

The current study suffers from some limitations that researchers must be aware of in future research. First, there is an inability to determine qualitative aspects such as time and cost when designing a composite indicator of financial inclusion. Second, due to limited data, we used only eight countries from the MENA. It is suggested to expand the sample to include other countries.

This paper contributes to the related literature between financial inclusion and financial stability by confirming or denying the results of previous studies. Also, to the best of the author’s knowledge, this paper is the only one that explains the role of financial development in the relationship between financial inclusion and stability in MENA countries, using a composite index to calculate financial inclusion. Finally, the study seeks to focus the attention of the government and policymakers to build a system of financial inclusion that leads to improving financial stability.

The purpose of this study is to investigate how the implementation of digital banking services (mobile applications) by globally systemically important banks (G-SIBs) affects banks’ performance in the USA and Europe from 2005 to 2022.

The study employs advanced econometric methods to analyze the link between deposits and banking performance, utilizing linear regressions and multivariate Bayesian regressions.

Our results indicate that customer deposits positively impact a bank’s performance after the introduction of the mobile application feature of check deposits, whereas social risk negatively impacts banking financial performance. These findings support the hypothesis that technology implementation improves the profitability and growth of traditional banks.

While findings are robust econometrically in linear and Bayesian regressions, variables reflecting the digitalization of banks remain limited. For instance, the number of mobile users or the volume of digital transactions per bank since the implementation of the mobile app is not available.

In a rapidly growing technology and constantly changing customers behaviors, this research has practical implications from bankers’ perspective to continue the technological innovation efforts and from regulators’ perspective to strengthen requirements for the digital banking services.

We provide empirical evidence that including a banking app for smartphones’ users for remote banking services benefit the financial performance of banks. However, the social risk remains significant for banks in terms of customers' satisfaction, data privacy and cybersecurity.

This paper employs an innovative approach to create a mobile app “discriminatory” factor and examine the relationship between deposits and banks’ performance before and after the introduction of a mobile app for too-big-to-fail banks in Europe and the USA. Additionally, we consider the social risk component of the ESG score, as a bank’s decision to implement mobile applications and technology for its customers potentially affects social risks associated with customer satisfaction and technology usability.

The corrosion of cupronickel and copper alloys in marine and chloride environments presents significant challenges in the chemical and petrochemical industries. This paper aims to investigate the corrosion inhibition of cupronickel alloy (Cu-10Ni) in a sodium chloride medium using expired amlodipine as a corrosion inhibitor. The use of this drug in its expired form could reduce the costs of corrosion and help mitigate the accumulation of pharmaceutical waste.

The inhibitory action was evaluated using a weight loss method, potentiodynamic polarization, electrochemical impedance spectroscopy measurements, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The effect of temperature on the inhibition performance was also studied.

The results of these experiments demonstrated that the drug amlodipine effectively inhibited the corrosion of cupronickel alloy in chloride solutions. The corrosion rate of cupronickel was found to decrease with increasing inhibitor concentration and to increase with rising temperature. A maximum inhibition efficiency of 91.92 was achieved with an inhibitor concentration of 0.025 g/L at 298 K. Adsorption of the inhibitor followed the Langmuir adsorption isotherm. Polarization studies indicated that the expired drug acted as a mixed inhibitor. SEM and AFM analyses confirmed that the surface morphology of cupronickel specimens was significantly improved in the presence of the inhibitor.

Amlodipine can be conveniently used to mitigate problems with the corrosion of copper alloys in chloride environments.

Amlodipine is evaluated as a novel and effective corrosion inhibitor for cupronickel alloy in neutral chloride environments.

Thermal energy storage systems use thermal energy to elevate the temperature of a storage substance, enabling the release of energy during a discharge cycle. The storage or retrieval of energy occurs through the heating or cooling of either a liquid or a solid, without undergoing a phase change, within a sensible heat storage system. In a sensible packed bed thermal energy storage system, the structure comprises porous media that form the packed solid material, while fluid occupies the voids. Thus, a cavity, partially filled with a fluid layer and partially with a saturated porous layer, has become important in the investigation of natural convection heat transfer, carrying significant relevance within thermal energy storage systems. Motivated by these insights, the current investigation delves into the convection heat transfer driven by buoyancy and entropy generation within a partially porous cavity that is differentially heated, vertically layered and filled with a hybrid nanofluid.

The investigation encompasses two distinct scenarios. In the first instance, the porous layer is positioned next to the heated wall, while the opposite region consists of a fluid layer. In the second case, the layers switch places, with the fluid layer adjacent to the heated wall. The system of equations for fluid and porous media, along with appropriate initial and boundary conditions, is addressed using the finite difference method. The Tiwari–Das model is used in this investigation, and the viscosity and thermal conductivity are determined using correlations specific to spherical nanoparticles.

Comprehensive numerical simulations have been performed, considering controlling factors such as the Darcy number, nanoparticle volume fraction, Rayleigh number, bottom slit position and Hartmann number. The visual representation of the numerical findings includes streamlines, isotherms and entropy lines, as well as plots illustrating average entropy generation and the average Nusselt number. These representations aim to provide insight into the influence of these parameters across a spectrum of scenarios.

The computational outcomes indicate that with an increase in the Darcy number, the addition of 2.5% magnetite nanoparticles to the GO nanofluid results in an enhanced heat transfer rate, showing increases of 0.567% in Case 1 and 3.894% in Case 2. Compared with Case 2, Case 1 exhibits a 59.90% enhancement in heat transfer within the enclosure. Positioning the porous layer next to the partially cooled wall significantly boosts the average total entropy production, showing a substantial increase of 11.36% at an elevated Rayleigh number value. Positioning the hot slit near the bottom wall leads to a reduction in total entropy generation by 33.20% compared to its placement at the center and by 33.32% in comparison to its proximity to the top wall.