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This study aims to computational numerical simulations to clarify and explore the influences of periodic cellular lattice (PCL) morphological parameters – such as lattice structure topology (simple cubic, body-centered cubic, z-reinforced body-centered cubic [BCCZ], face-centered cubic and z-reinforced face-centered cubic [FCCZ] lattice structures) and porosity value ( ) – on the thermal-hydraulic characteristics of the novel trussed fin-and-elliptical tube heat exchanger (FETHX), which has led to a deeper understanding of the superior heat transfer enhancement ability of the PCL structure.

A three-dimensional computational fluid dynamics (CFD) model is proposed in this paper to provide better understanding of the fluid flow and heat transfer behavior of the PCL structures in the trussed FETHXs associated with different structure topologies and high-porosities. The flow governing equations of the trussed FETHX are solved by the CFD software ANSYS CFX® and use the Menter SST turbulence model to accurately predict flow characteristics in the fluid flow region.

The thermal-hydraulic performance benchmarks analysis – such as field synergy performance and performance evaluation criteria – conducted during this research successfully identified demonstrates that if the high porosity of all PCL structures decrease to 92%, the best thermal-hydraulic performance is provided. Overall, according to the obtained outcomes, the trussed FETHX with the advantages of using BCCZ lattice structure at 92% porosity presents good thermal-hydraulic performance enhancement among all the investigated PCL structures.

To the best of the authors’ knowledge, this paper is one of the first in the literature that provides thorough thermal-hydraulic characteristics of a novel trussed FETHX with high-porosity PCL structures.

Drawing on work from home (WFH), job demand-control and street-level bureaucracy literature streams, this paper specifically focuses on the emerging trend of WFH for public sector employees in a developing country context of Egypt.

The empirical sample comprises focus group discussions with a total of 40 public sector employees in Egypt. Thematic analysis was subsequently used on focus group discussion transcripts to bring out main themes linked to this topic.

Our findings show that employee (marginal discretion power, pharaonism, corruption), citizen (unfamiliarity with digital services) and country (lack of proper info-structure, overstaffing in the public sector)- level challenges hinder and/or slow down the potential for WFH in Egyptian public sector.

A major implication of our paper relates to highlighting the criticality of e-governance and WFH for public sector employees, as well as highlighting multilevel challenges associated with those. At the same time, socio-economic and political consequences of offering such options need to be considered in a country like Egypt where most public organisations are overstaffed, and those employees lack modern day employability skills. Hence, there needs to be an open debate in countries such as Egypt on the consequences of e-governance and WFH and whether it may facilitate delivering citizen services digitally. Also, high power distance culture plays a role in this context, and any change cannot be successful unless that specific aspect is confronted.

This study contributes to the emerging WFH literature by being one of the pioneering studies to offer a multilevel (micro, meso and macro) assessment of this phenomenon in the under-researched fragile developing country’s context.

The outbreak of COVID-19 not only had serious negative impacts on the world economy but also on the global mental health because of the psychological disorders associated with the spread of the pandemic, the increased degree of uncertainty and the unprecedented measures taken by different countries to face the pandemic’s spread. This paper analyses the mental health well-being of individuals in selected MENA countries (Jordan, Morocco, Tunisia and Egypt) during the pandemic.

The study employs a pooled OLS model using the Economic Research Forum (ERF) COVID-19 MENA Monitor Survey panel dataset collected during 2020 and 2021.

The findings show that there is no association between the mental health of individuals in the selected countries and their age, gender, family size, marital status, receipt of social support and participation in care work. Mental health improved at higher levels of education, being employed, being a rural area resident and living in Morocco or Tunisia compared to living in Jordan while it worsened as income declined, food insecurity and anxiety about being infected with Covid-19 increased, being a resident in camps, and during waves 4 and 5. Based on these results, it is recommended that suitable financial, physical and human resources should be directed towards the provision of mental health care services in the region. Also, mental health care services should be accessible to different population groups, with a special focus towards the most vulnerable since they are more prone to mental illnesses, especially during health crises and economic shocks. This should be accompanied by increasing awareness about the provided services and reducing stigma against mental illnesses. Furthermore, introduction of policies targeted towards reducing food insecurity and income instability can play a key role in enhancing mental well-being.

Although few papers have previously investigated the impact of COVID-19 on mental health in MENA countries, most of them have focused on a country-level analysis and adopted a gender perspective. Hence, this paper aims at exploring the association between mental health well-being and socio-economic factors in selected MENA countries during the pandemic.

This paper aims to analyze the determinants on job satisfaction in the Egyptian labor market, using Egypt’s Labor Market Panel Survey (ELMPS), the wave of 2012.

Several determinants are analyzed including the wage level, the paid and sick leaves, the medical and social insurance, job stability among other individual and job characteristics. To this end, an ordered logit model is estimated to assess the significance of these different variables as determinants for job satisfaction.

The empirical findings indicate that wages and stability are major determinants for job satisfaction for the sample of wage workers. However, the results change according to gender; the hourly wage level affects men’s level of job satisfaction, while it does not affect that of females. Furthermore, the job satisfaction of women is determined more by the job characteristics rather than the monetary compensation.

The empirical findings shed light on the importance of formalizing jobs, as it has an effect on the level of job satisfaction of both women and men.

To the best of the authors’ knowledge, this is the first paper to examine the determinants of job satisfaction for wage workers in Egypt using the ELMPS data.

The birth and survival rate of youth-owned businesses has been a major concern for policymakers, industry and academics alike. Learning and innovation play important roles and more critical is the mediating factors and how it impacts the enterprise competitiveness of youth-owned businesses and hence worth studying. Therefore, this study aims to examine the impact of mediating factors such as government support, informal network society and external knowledge infrastructure on learning and innovation in youth-owned small businesses in Lagos, Nigeria, from a cross-sectional perspective.

Leveraging the sectoral system of innovation theory, we use a primary research method and data obtained from a structured questionnaire administered among a sample of 1,000 registered youth-owned small businesses in Lagos, while 30 in-depth interviews were also conducted. The exploratory factor analysis was used for data examination.

The findings show that even though government support, informal network society and external knowledge all have a positive relationship with learning and innovation in youth-owned small businesses, government support has the most impactful impact. The informal network society via a trade association, professional network and social media are also critical in knowledge transfer in youth-owned businesses.

The significance of learning and innovation is more important as many small businesses do not have the privilege of standard human resource management (HRM) systems. This paper looks at the mediating factors affecting the introduction of innovative practices in youth-owned and managed small businesses and how productivity is enabled in a developing county context.

This paper aims to identify the level of contribution of different levels of education to remaining in unemployment as well as the transition from unemployment to employment in Egypt.

In this paper, transition probabilities matrix differentiated by gender, age groups, educational levels, marital status and place of residence based on worker flows across employment, unemployment and out of labor force states during the period 2012–2018 using Egypt Labor Market Panel Survey of 2018. The results point to the highly static nature of the Egyptian labor market. Employment and the out of labor force states are the least mobile among labor market states. This is because employment state is very desirable and the out of labor force is the largest labor market states, especially for females. Also, this study examines the impact of different educational levels separately on remaining in unemployment and transition from unemployment to employment state using eight binary logistic regression models.

The main results of transitions from unemployment to employment are relatively large for males, elder-age, uneducated workers as well as workers who are not married and urban residents, and the results of the logistic regression models consistent with the transition probabilities matrix results, except for few cases. Based on the above findings, there is enough evidence to accept the null hypothesis that no education has a positive significant impact to transition unemployed individuals from unemployment to employment, while less than intermediate as well as higher education have a negative significant impact to transition unemployed individuals from unemployment to employment.

This paper proposes to address the problem of the unemployment among highly educated which is much higher compared with illiterates and try to understand the impact of different levels of education separately on the transition from unemployment to employment, to help the policymakers to eradicate the gap between education and the demand of the labor market in Egypt.

Like many social media trends, the romantic craze charms Egyptian youth. Romantic Facebook crush pages popped up locally in the past few years among university students particularly. They expressed a new aspect of online social interaction that has raised red flags with some adults, while thought to be a new healthy way to pour youth’s hearts out anonymously in a so-called a conservative society for others. Some crush pages, in particular, drew concerns of several parents for they are more vulgar and aggressive submissions. Laying between the two arguments, this study aims to examine the extent to which Facebook users make use of it to pursue romance, if Facebook’s characteristics and social context reflected in users’ perceptions of romantic relationships, the implications of being in a romantic relationship on Facebook and if such FB practices could pose a state of moral panic or a public concern.

A survey of 200 Facebook users between 18 and 25 years was gathered. Furthermore, a content analysis of three Egyptian universities’ “crush pages” posts was applied.

The study highlighted the conflicting ideals of today’s Egyptian youth moral lives. Ultimately, there is an evidence that practices of using Facebook online crush pages have been creating new contested but delightful moral normative rules around love.

Crushes pages have been sweeping across Egyptian colleges and faculties; however, almost no Arabic study was done to figure out its impact. Furthermore, the study takes into account the socio-cultural background of the Egyptian society.

In this study, response surface methodology (RSM) is applied to a three-point bending stiffness analysis of low-cost material (PLA) specimens printed using FDM technology to analyze the performance of different internal lattice structures (Octet and IsoTruss principally). The purpose of this study is to extend the definition from a discrete (lattice) model to an analytical one for its use in subsequent design phases, capable of optimizing the type of cell to be used and its defining parameters to find the best stiffness-to-weight ratio.

The representative function of their mechanical behavior is extrapolated through a two-variable polynomial model based on the cell size and the thickness of the beam elements characterizing it. The polynomial is obtained thanks to several tests performed according to the scheme of RSM. An analysis on the estimation errors due to discontinuities in the physical specimens is also conducted. Physical tests applied to the specimens showed some divergences from the virtual (ideal) behavior of the specimens.

The study allowed to validate the RSM models proposed to predict the behavior of the system as the size, thickness and type of cells vary. Changes in stiffness and weight of specimens follow linear and quadratic models, respectively. This generally allows to find optimal design points where the stiffness-to-weight ratio is at its highest.

Although the literature provides numerous references to studies characterizing and parameterizing lattice structures, the industrial/practical applications concerning lattice structures are often still detached from theoretical research and limited to achieving functioning models rather than optimal ones. The approach here described is also aimed at overcoming this limitation. The software used for the design is nTop. Subsequent three-point bending tests have validated the reliability of the model derived from the method’s application.