Roma G. Elfadel, Hala M. Refat, H. Abdelwahab, Salem S. Salem, Mohamed A. Awad and M.A.M. Abdel Reheim
This paper aims to investigate the prepared modified alkyd and poly(ester-amide) (PEA) resins as antimicrobial and insecticide binders for surface coating applications.
Abstract
Purpose
This paper aims to investigate the prepared modified alkyd and poly(ester-amide) (PEA) resins as antimicrobial and insecticide binders for surface coating applications.
Design/methodology/approach
Salicylic diethanolamine and 4-(N, N-dimethylamino) benzylidene glutamic acid were prepared and used as new sources of polyol and dibasic acid for PEA and alkyd resins, then confirmed by: acid value, FT-IR and 1H-NMR. The coating performance of the resins was determined using measurements of physico-mechanical properties. The biological and insecticide activities of the prepared resins were investigated.
Findings
The tests carried out revealed that the modified PEA and alkyd enhanced both phyisco-mechanical and chemical properties in addition to the biological and insecticide activities. The results of this paper illustrate that the introduction of salicylic diethanolamine and 4-(N, N-dimethylamino) benzylidene glutamic acid within the resin structure improved the film performance and enhanced the antimicrobial activity performance of PEA and alkyd resins.
Research limitations/implications
The modified alkyd and PEA organic resins can be used as biocidal binders when incorporated into paint formulations for multiple surface applications, especially those that are exposed to several organisms.
Originality/value
Modified alkyd and PEA resins based on newly synthesized modifiers have a significant potential to be promising in the production and development of antimicrobial and insecticide paints, allowing them to function to restrict the spread of insects and microbial infection.
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This research aims to present an aero-propulsive interaction model applied to conceptual aircraft design with distributed electric propulsion (DeP). The developed model includes a…
Abstract
Purpose
This research aims to present an aero-propulsive interaction model applied to conceptual aircraft design with distributed electric propulsion (DeP). The developed model includes a series of electric ducted fans integrated into the wing upper trailing edge, taking into account the effect of boundary layer ingestion (BLI). The developed model aims to estimate the aerodynamic performance of the wing with DeP using an accurate low-order computational model, which can be easily used in the overall aircraft design's optimization process.
Design/methodology/approach
First, the ducted fan aerodynamic performance is investigated using a low-order computational model over a range of angle of attack required for conventional flight based on ducted fan design code program and analytical models. Subsequently, the aero-propulsive coupling with the wing is introduced. The DeP location chordwise is placed at the wing's trailing edge to have the full benefits of the BLI. After that, the propulsion integration process is introduced. The nacelle design's primary function is to minimize the losses due to distortion. Finally, the aerodynamic forces of the overall configuration are estimated based on Athena Vortex Lattice program and the developed ducted fan model.
Findings
The ducted fan model is validated with experimental measurements from the literature. Subsequently, the overall model, the wing with DeP, is validated with experimental measurements and computational fluid dynamics, both from the literature. The results reveal that the currently developed model successfully estimates the aerodynamic performance of DeP located at the wing trailing edge.
Originality/value
The developed model's value is to capture the aero-propulsive coupling accurately and fast enough to execute multiple times in the overall aircraft design's optimization loop without increasing runtime substantially.
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M.M. Elsawy, Mohamed A. Awad, Nashwa M. Saleh and H. Abd El-Wahab
Paper aims to Preparation and evaluation of isoxazole benzene sulfonamide derivatives and incorporated it with waterborne household paints to develop coating compositions as an…
Abstract
Purpose
Paper aims to Preparation and evaluation of isoxazole benzene sulfonamide derivatives and incorporated it with waterborne household paints to develop coating compositions as an insecticidal coating against Musca domestica adults.
Design/methodology/approach
The synthesized compounds were prepared and confirmed by different analyzes, fourier transform infra-red (FTIR), mass, proton nuclear magnetic resonance (1HNMR) and Carbon 13 nuclear magnetic resonance (13CNMR) spectra. The prepared compound has been blended with waterborne household paint formulation, the physical and mechanical properties of the paint formulation has been studied. The efficiency of the isoxazole benzene sulfonamide derivatives when incorporated with waterborne paint against Culex quinquefasciatus and Mosquito house fly adults, also have been examined.
Findings
The obtained results of the paint formulations confirmed their best performance and providing good scrub resistance. Also, the finding promising results of the insecticide test of the paint formulation may be because of the biological activity of these compounds and containing sulfonamide, cyanide and free aromatic amine groups comparing with the standard recommended organophosphorus insecticide. The order activity increase with increasing the dose concentration of the isoxazole derivatives and the activity of chemical compounds itself is represented in terms of their medium lethal concentrations LC50 (LC90), which recorded 0.90(1.62), 0.89(1.61) and 0.86(1.56) g/ml for 5, 3 and 4 chemical compounds, respectively, after 72 h from treatment.
Practical implications
These types of organic compounds are friendly environmentally and can be used as a biocide with different types of paint formulations.
Originality/value
Insecticide waterborne household paints based on isoxazole benzene sulfonamide derivatives as insecticide agents are novel.
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Mohamed Awad El Araby and Noor el Dien Salem Ayaad
The main target of the study represented in developing a proposed Quantitative Model for the purpose of measuring the administrative performance of public governmental…
Abstract
Purpose
The main target of the study represented in developing a proposed Quantitative Model for the purpose of measuring the administrative performance of public governmental organizations, taking into account the validity of the model for many different contexts in practice through governmental sector.
Design/methodology/approach
Depending on statistical approach, both authors tried to handle this issue through assessing institutional performance in the state owned units on many levels starting from individual level (HR and leaders), sub-units, organization level, then deriving an aggregated formula for assessing general institutional performance of the whole public body in one state, depending on reviewing some of concerned literatures.
Findings
The authors could already formulate some proposed criteria for assessing and measuring institutional performance on three different levels.
Originality/value
Although the topic is considered one of the most complicated areas of institutional reform trends, the idea remains very vital as a step forward to improving public policy implementation in the governmental sector, besides that it is correlated to institutional capacity building process in practice.
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The purpose of the paper is to showcase the significant achievements of Egypt's scientists in the 20th century across various fields of study such as medicine, physics, chemistry…
Abstract
Purpose
The purpose of the paper is to showcase the significant achievements of Egypt's scientists in the 20th century across various fields of study such as medicine, physics, chemistry, biology, math, geology, astronomy and engineering. The paper highlights the struggles and successes of these scientists, as well as the cultural, social and political factors that influenced their lives and work. The aim is to inspire young people to pursue careers in science and make their own contributions to society by presenting these scientists as role models for hard work and dedication. Ultimately, the paper seeks to promote the importance of science and its impact on society.
Design/methodology/approach
The purpose of this review is to present the scientific biographies of Egypt's most distinguished scientists, primarily in the field of Natural Sciences, in a balanced and comprehensive manner. The work is objective, honest and abstract, avoiding any bias or exaggeration. The author provides a clear and concise methodology, including a brief introduction to the scientist and their field of study, an explanation of their major contributions, the impact of their work on society, any challenges or obstacles faced during their career and their lasting legacy. The aim is to showcase the important achievements of these scientists, their impact on their respective fields and to inspire future generations to pursue scientific careers.
Findings
The group of outstanding scientists in 20th century Egypt were shaped by various factors, including familial upbringing, education, society, political and cultural atmosphere and state support for scientific research. These scientists made significant contributions to various academic disciplines, including medicine, physics, chemistry, biology, mathematics and engineering. Their impact on their communities and cultures has received international acclaim, making them role models for future generations of scientists and researchers. The history of these scientists highlights the importance of educational investments and supporting scientific research to foster innovation and social progress. The encyclopedia serves as a useful tool for students, instructors and education professionals, preserving Egypt's scientific heritage and honouring the scientists' outstanding accomplishments.
Research limitations/implications
The encyclopedia preserves Egypt's scientific heritage, which has been overlooked for political or other reasons. It is a useful tool for a variety of readers, including students, instructors and education professionals, and it offers insights into universally relevant scientific success factors as well as scientific research methodologies. The encyclopedia honours the outstanding scientific accomplishments of Egyptian researchers and their contributions to the world's scientific community.
Practical implications
The practical implications of this paper are several. First, it highlights the importance of education, family upbringing and societal support for scientific research in fostering innovation and social progress. Second, it underscores the need for continued funding and support for scientific research to maintain and build upon the accomplishments of past generations of scientists. Third, it encourages young people to pursue scientific careers and make their own contributions to society. Fourth, it preserves the scientific heritage of Egypt and honors the contributions of its outstanding scientists. Finally, it serves as a useful tool for students, instructors and education professionals seeking to understand the factors underlying scientific success and research methodologies.
Social implications
The social implications of the paper include promoting national pride and cultural identity, raising awareness of the importance of education and scientific research in driving social progress, inspiring future generations of scientists and researchers, reducing socioeconomic disparities and emphasizing the role of society, politics and culture in shaping scientific researchers' personalities and interests.
Originality/value
The paper's originality/value lies in its comprehensive documentation of the scientific biographies of Egypt's most prominent scientists in the 20th century, providing unique insights into the factors that contributed to their development and their impact across various academic disciplines. It preserves Egypt's scientific heritage and inspires future generations of scientists and researchers through the promotion of educational investments and scientific research. The encyclopedia serves as a useful tool for education professionals seeking to understand scientific success factors and research methodologies, emphasizing the importance of supportive and inclusive environments for scientific development.
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Mohammad Jahanbakht and Farzad Ahmadi
The purpose of this study is to investigate the influence of external enablers (EEs) – factors that are exogenous and independent of the actors – on the rate of new venture…
Abstract
Purpose
The purpose of this study is to investigate the influence of external enablers (EEs) – factors that are exogenous and independent of the actors – on the rate of new venture creation (NVC) in digital entrepreneurship.
Design/methodology/approach
The authors established a unique data panel comprising all formal digital entrepreneurial firms and startups licensed to operate in the digital space from Iran E-Commerce Development Center, from 2012 to 2022, totaling 124,751 businesses classified in 16 sectors. The authors used Poisson regression with robust standard errors to analyze the relationship between external factors and NVC. Additionally, the authors segmented the data set along demographic, spatial and sectoral subsets to compare them using the average treatment effect model.
Findings
This analysis confirms that technology readiness and technology intensity, as EEs, significantly boost digital entrepreneurship in a developing country. The authors also explored the impact of the COVID-19 pandemic as a natural environmental enabler and explored its facilitating effects and the enduring impacts post-pandemic. Moreover, the authors assessed the heterogeneous impact of the EEs across different groups and derived implications for each.
Research limitations/implications
While this study is comprehensive, it focuses exclusively on formal digital entrepreneurship within a single developing country, namely, Iran. Although the authors explored various EEs, they did not address all possible types, highlighting the potential for further research in other entrepreneurial sectors for a comparative analysis of EEs.
Practical implications
The initial findings affirm that most NVC in Iran stems from external factors. These findings have been widely used by policymakers to define the goals and objectives of EEs concerning their nature and impact. This research reveals that EEs have heterogeneous effects on NVC, varying across different characteristics such as gender, geography and industry sectors. The results of this study suggest that governments should reassess the role of “macro” policies to support vulnerable groups. EEs disproportionately benefit male founders, which exacerbates existing gender gaps and necessitates ongoing attention and intervention. Additionally, EEs have diverse impacts across industries, potentially favoring some while disadvantaging others because of varying social, cultural and economic factors.
Originality/value
NVC, central to entrepreneurship in developing nations, encounters numerous challenges, yet the role of EEs remains underexplored in this context. EEs are opportunities that are not limited to a subset of entrepreneurial actors; they act as levers influencing a wide range of entrepreneurial activities. This research distinctively investigates the empirical impact of EEs in a Middle Eastern developing country context, contributing to the growing literature on the external enablers framework.
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Rishi Kapoor Ronoowah and Boopen Seetanah
The purpose of this study is to examine the linear and non-linear relationship between capital structure (CS) and firm performance (FP) and the moderating and mediating roles of…
Abstract
Purpose
The purpose of this study is to examine the linear and non-linear relationship between capital structure (CS) and firm performance (FP) and the moderating and mediating roles of agency costs in the CS-FP nexus.
Design/methodology/approach
This study used static and quadratic panel data regression models to examine the linear and non-linear relationships and structured equation models to analyze the mediating effect of agency costs in the CS-FP nexus of 38 listed non-financial Mauritian firms from 2009 to 2019.
Findings
Leverage has a significant negative effect on FP supporting the pecking order theory. Agency costs are significantly and positively associated with FP. There is a strong non-linear relationship between leverage and FP supporting the trade-off and agency cost theories. Agency costs are an important moderator and mediator in the CS-FP nexus. Overall, the sensitivity analyses showed that the results were robust.
Practical implications
Firms need to carefully consider the levels and types of debt and equity in their CS involving the use of dynamic strategies to adjust CS in response to changing economic conditions and FP. The moderating effect of agency costs may guide firms in optimizing CS and may contribute to corporate governance discussions, emphasizing the importance of aligning interests to foster sustainable business practices.
Originality/value
This study adds to the extant literature by providing new evidence on the non-linear relationship between leverage and FP and the moderating and mediating roles of agency costs in the CS-FP nexus in emerging capital markets, where such studies are rare.
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Sudan’s ruling party, its capabilities and political implications.
Details
DOI: 10.1108/OXAN-DB217188
ISSN: 2633-304X
Keywords
Geographic
Topical
Mohamed Aseel Shokr, Zulkefly Abdul Karim and Mohd Azlan Shah Zaidi
This paper aims to examine the effects of monetary policy and foreign shocks on output, inflation and exchange rate in Egypt.
Abstract
Purpose
This paper aims to examine the effects of monetary policy and foreign shocks on output, inflation and exchange rate in Egypt.
Design/methodology/approach
This paper studies the effects of monetary policy and foreign shocks on output, inflation and exchange rate by using non-recursive SVAR model and quarterly data.
Findings
First, the empirical results reveal that monetary policy shocks, through changes in interest rate or money supply, have a significant effect on output, inflation and exchange rate in Egypt. Second, the world oil prices and foreign output have significant impacts on output, inflation and exchange rate in Egypt, while foreign interest rate has a significant effect on domestic output and inflation.
Research limitations/implications
The limitation of the study is examining one country only.
Practical implications
The Central Bank of Egypt (CBE) should adjust interest rate to stabilize inflation, output and exchange rate. By stabilizing inflation, output and exchange rate, the CBE would be able to achieve the ultimate targets of monetary policy, namely, price stability and economic growth.
Social implications
It is important for the CBE because it shows the significant effect of monetary policy on macroeconomic variables in Egypt. Also, it is important for people because it shows the important role for the CBE.
Originality/value
It is important for the CBE because it examines the effect of monetary policy and foreign shocks on macroeconomic variables.
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Mosa Abdelgelil Amin, Eman Mohamed Abdelmaged, Awad Elsayed Ibrahim and Tarek Abdelfattah
This study aims to investigate the relationship between Chief Executive Officer (CEO) characteristics and audit report lag (ARL) in Egypt, an emerging economy characterized by…
Abstract
Purpose
This study aims to investigate the relationship between Chief Executive Officer (CEO) characteristics and audit report lag (ARL) in Egypt, an emerging economy characterized by high power distance and a culture of secrecy. The study utilizes a theoretical framework that integrates agency theory, stewardship theory, and upper echelons theory as the foundation for examining this relationship.
Design/methodology/approach
The sample consists of 587 firm-year observations from non-financial firms listed on the EGX100, covering the period from 2012 to 2019. The primary variable of the study (ARL) is measured using different proxies. The analysis utilizes both Ordinary Least Squares (OLS) and logistic regression models, with additional analysis considering CEO power and using board gender diversity as a moderating variable.
Findings
The study finds that CEO characteristics significantly affect ARL, demonstrating a negative association between CEO ownership, founder status, family ties, duality and ARL. These findings remain robust after a series of tests using alternative measures. Additional analysis reveals that CEO power is negatively and significantly related to ARL. Interestingly, the negative association between CEO characteristics and ARL is more pronounced in boards without female members.
Originality/value
Although extensive research has been conducted on the factors determining ARL, few studies have examined the impact of CEO characteristics on ARL, particularly in emerging economies such as Egypt. The business environment in Egypt is characterized by high power distance and a secretive culture, providing a unique context for this study.