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The purpose of the study is to obtain explicit formulas to determine the stability of periodic solutions to the new system and study the extent of the stability of those periodic solutions and the direction of bifurcated periodic solutions. More than that, the authors did a numerical simulation to confirm the results that the authors obtained and presented through numerical analysis are the periodic and stable solutions and when the system returns again to the state of out of control.

The authors studied local bifurcation and verified its occurrence after choosing the delay as a parameter of control in Zhou 2019’s dynamical system with delayed feedback control. The authors investigated the normal form theory and the center manifold theorem.

The occurrence of local Hopf bifurcations at the Zhou's system is verified. By using the normal form theory and the center manifold theorem, the authors obtain the explicit formulas for determining the stability and direction of bifurcated periodic solutions. The theoretical results obtained and the corresponding numerical simulations showed that the chaos phenomenon in the Zhou's system can be controlled using a method of time-delay auto-synchronization.

As the delay increases further, the numerical simulations show that the periodic solution disappears, and the chaos attractor appears again. The obtained results can also be applied to the control and anti-control of chaos phenomena of system (1). There are still abundant and complex dynamical behaviors, and the topological structure of the new system should be completely and thoroughly investigated and exploited.

Compact and wideband antennas are the need of modern wireless systems that preferably work with compact, low-profile and easy-to-install devices that provide a wider coverage of operating frequencies. The purpose of this paper is to propose a novel compact and ultrawideband (UWB) microstrip patch antenna intended for high frequency wireless applications.

A square microstrip patch antenna was initially modeled on finite element method-based electromagnetic simulation tool high frequency structure simulator. It was then loaded with a rectangular slit and Koch snowflake-shaped fractal notches for bandwidth enhancement. The fabricated prototype was tested by using vector network analyzer from Agilent Technologies, N5247A, Santa Clara, California, United States (US).

The designed Koch fractal patch antenna is highly compact with dimensions of 10 × 10 mm only and possesses UWB characteristics with multiple resonances in the operating band. The −10 dB measured impedance bandwidth was observed to be approximately 13.65 GHz in the frequency range (23.20–36.85 GHz).

Owing to its simple and compact structure, positive and substantial gain values, high radiation efficiency and stable radiation patterns throughout the frequency band of interest, the proposed antenna is a suitable candidate for high frequency wireless applications in the K (18–27 GHz) and Ka (26.5–40 GHz) microwave bands.

This study aims to test the mediating effect of psychological distress and bullying victimization on the relationship between alexithymia and fibromyalgia (FM) among school adolescents.

This study used cross-sectional, correlational design. Data was collected using self-administered questionnaire. The sample consisted of 1,000 school adolescents at Grade 9–12 who were recruited randomly using multistrategic sampling technique.

The analysis showed that alexithymia was a significant predictor of FM (odds ratio [OR] = 1.065). Psychological distress was also a significant predictor of FM; however, its mediating effect resulted in drop of OR to 1.041. The joined effect of bulling victimization and psychological distress found to be significant although OR dropped from 1.065 to 1.039.

The study highlights the significant role of school health nurses and mental health counselors to early detect and direct mental health interventions toward significant psychological problems among school adolescents.

I affirm this information has not been published or submitted for publication elsewhere. All authors approve the content of the manuscript and have contributed significantly to research involved/ the writing of the manuscript. The authors affirm their commitment to transfer copyright ownership to your journal if the manuscript is accepted for publication. The authors also affirm they will obtain any other copyright permission if deemed necessary within 30 days of acceptance for publication. All identifying information regarding the study participants has been omitted and this study was approved by the IRB at School of Nursing of the University of Jordan. The research conforms to the provisions of the Declaration of Helsinki in 1995 (as revised in Brazil, 2013). All participants gave informed consent for the research, and that their anonymity was preserved. None of the authors has financial or personal matters that may pose a conflict of interest.

The particle distribution in a fluid is mostly not homogeneous. The inhomogeneous dispersion of solid particles affects the velocity profile as well as the heat transfer of fluid. This study aims to highlight the effects of varying density of particles in a fluid. The fluid flows through a wavy curved passage under an applied magnetic field. Heat transfer is discussed with variable thermal conductivity.

The mathematical model of the problem consists of coupled differential equations, simplified using stream functions. The results of the time flow rate for fluid and solid granules have been derived numerically.

The fluid and dust particle velocity profiles are being presented graphically to analyze the effects of density of solid particles, magnetohydrodynamics, curvature and slip parameters. Heat transfer analysis is also performed for magnetic parameter, density of dust particles, variable thermal conductivity, slip parameter and curvature. As the number of particles in the fluid increases, heat conduction becomes slow through the fluid. Increase in temperature distribution is noticed as variable thermal conductivity parameter grows. The discussion of variable thermal conductivity is of great concern as many biological treatments and optimization of thermal energy storage system’s performance require precise measurement of a heat transfer fluid’s thermal conductivity.

This study of heat transfer with inhomogeneous distribution of the particles in a fluid has not yet been reported.

This study’s fundamental objective is to assess climate change impact on reference evapotranspiration (ET_o) patterns in Egypt under the latest shared socioeconomic pathways (SSPs) of climate change scenarios. Additionally, the study considered the change in the future solar radiation and actual vapor pressure and predicted them from historical data, as these factors significantly impact changes in the ET_o.

The study utilizes data from the Coupled Model Intercomparison Project Phase 6 (CMIP6) models to analyze reference ET_o. Six models are used, and an ArcGIS tool is created to calculate the monthly average ET_o for historical and future periods. The tool considers changes in actual vapor pressure and solar radiation, which are the primary factors influencing ET_o.

The research reveals that monthly reference ET_o in Egypt follows a distinct pattern, with the highest values concentrated in the southern region during summer and the lowest values in the northern part during winter. This disparity is primarily driven by mean air temperature, which is significantly higher in the southern areas. Looking ahead to the near future (2020–2040), the data shows that Aswan, in the south, continues to have the highest annual ET_o, while Kafr ash Shaykh, in the north, maintains the lowest. This pattern remains consistent in the subsequent period (2040–2060). Additionally, the study identifies variations in ET_o , with the most significant variability occurring in Shamal Sina under the SSP585 scenario and the least variability in Aswan under the SSP370 scenario for the 2020–2040 time frame.

This study’s originality lies in its focused analysis of climate change effects on ET_o, incorporating crucial factors like actual vapor pressure and solar radiation. Its significance becomes evident as it projects ET_o patterns into the near and distant future, providing indispensable insights for long-term planning and tailored adaptation strategies. As a result, this research serves as a valuable resource for policymakers and researchers in need of in-depth, region-specific climate change impact assessments.

Refugee camps are not easily welcomed by local communities. The purpose of this paper is to outline a structured approach to support the decision-making process for siting refugee camps in mainland Greece using multiple criteria, including local opposition. A suitability analysis generates a list of potential sites and a multiple criteria evaluation is applied. The motivation is the development of a methodology that can support choices and policies regarding the refugee camps siting problem, incorporating the need to address local opposition.

The proposed methodology combines geographic information systems (GIS) with multiple criteria decision-making (MCDM) techniques. These are used to develop a location classification and ranking model based on related criteria and subcriteria, attributes and weights. The region of Peloponnese in Greece is selected as a case study to validate the approach.

The lack of predefined candidate sites for refugee camps necessitates, initially, tackling a site search problem to generate a pool of potential sites through a suitability analysis. Subsequently, using the GIS the pool yields a subset of potential sites, satisfying all the criteria to setup a refugee camp. Through the current analysis the suitability of the single existing refugee camp site in Peloponnese can be evaluated. Finally, a “with and without” analysis, excluding the social criterion, depicts the changes in the candidate sites pool and their scores.

There is a lack of relevant literature taking into account the local opposition or sociopolitical implications as decision criteria. The selection of the appropriate criteria is a complex process that involves the cooperation of many experts. The main criteria, subcriteria and their attributes were determined according to existing literature and authors' informed judgment.

The proposed methodology can help decision-makers to setup a decision-making system and process for identifying refugee camps' sites using multiple criteria, including local opposition.

The purpose of this study is to investigate Libyan journalists’ perspectives regarding the media laws Articles 37,132, 38 and 46, which address media freedom in the new Libyan Constitution of 2017.

Focus group discussions were done with 35 Libyan journalists, 12 of them from the Constitution Committee, while 23 of them reported the update of the constitution in the Libyan Parliament.

The results of the study indicated that there were media laws articles that did not conform to the international laws and United Nations treaties, which the Libyan Parliament committee approved. Another finding from the journalists was the Constitution should provide and guarantee press freedom, while media laws articles approved to put a paragraph about “censorship” in the press and media as a tool to silence government opposition. In addition, journalists indicated future constitution should redraft Article 38 to conform with Article 19 of the “International Covenant on Civil and Political Rights,” to support the “principles of freedom of expression and information” without control. Moreover, Article 46 needs to be changed and linked to the “provisions of international law on the right of information access” to improve the access and dissemination of information in the media.

Redrafting the constitution articles in the future can be summarised as follows: First, the Libyan Constitution should provide and guarantee press freedom without any censorship and include clear articles to protect journalists in conflict zones. Second, Articles 37,132 and 38, about “freedom of information and publication,” need to be redrafted to link with Article 19 of the “International Covenant on Civil and Political Rights,” to support the principles of freedom of expression and information, and the use of this right must not be subject to prior control. Third, Article 46 needs to be changed and linked to the provisions of “International law on the Right of Access to Information” to improve access and dissemination of information in the media to protect confidentiality sources. The most important articles should be implemented (freedom of information and personal information act) because after the Arab Spring revolutions, there was a transitional period in societies and a change in the constitutions of Tunisia and Egypt. They developed legal articles about media freedom so that Libya resembles other Arab countries. From that point, the journalists recommended that all information should be protected from government interference to ensure transparency, combat corruption and protect independent journalists. These articles will open the way to add more development articles to media freedom rules in the Journalists’ Syndicate. Fourth, there are also various types of threats encountered by journalists in their work. In pursuit of their right and freedom of expression, they recommended that Libya must establish an independent self-regulatory media that are free from political and economic influence. Fifth, journalists need licenses for them to work through the syndicate. The new syndicate should play an active role to safeguard the rights of journalists, activists and media entities to carry out their work and end the self-censorship. Sixth, the constitution should also add articles to end the impunity and change the articles in the penal code. Overall, the journalists covering the conflict and war are encountering threats, violence and imprisonment. As a result, Libyan journalists must seek new legislation to defend independent journalism and freedom of expression in their deeply divided country. In addition, they need to have a strong central authority to defend journalists and journalism in wartime, where journalists are regularly threatened, abducted and sometimes killed. Also, the Libyan Journalists Syndicate should stress the importance of the media’s self-regulation to guarantee their rights to freedom of expression, grant their readers’ respect and minimise government’s interference. Finally, they need to develop new laws to grant media freedom from regulations and restrictions, as well as defend and promote democracy, the citizens’ right to be informed, as well as their right to discuss and disseminate information. There is also the need to implement articles in the constitution, articles about the protection of political speech, which would be specific enough to differentiate between what is legally permitted and what may be ethically offensive.

This study will help the new Libyan parliament after the legislative elections on 24 December 2021 to amend the media laws articles in the constitution.

This paper aims at contributing to our understanding of how self-settled Syrian refugees (registered and non-registered) use informal practices to forge their non-political agency and how this agency could be considered as political acts.

This paper was conducted per the qualitative data analysis (in-depth interviews and participant observation), attributed to the critical ethnographic approach, through which refugees’ everyday struggle is explored, additionally, that was incorporated with the analysis of Syrians’ Facebook groups and formal sources.

The research paper concluded that everyday struggle strategies are considered as political acts by acquiring rights that many self-settled Syrian refugees are stripped of by international humanitarian agencies and host government. Hence, registered and unregistered refugees equally forge what is called “informal citizenship” through their presence via a blend of agency forms ranging from hidden agency to explicit one and via their incorporating into the informal contexts, leading them to carve a position of semi-legality that help them to circumvent the formal structural hardship.

This paper endeavors to study how urban refugees as change agents can convert their illegal presence to “probably refugeeness” to unsettle the prominent recognition of them as illegal non-citizens in southern cities.

The purpose of this paper is to study haemodynamic flow characteristics and entropy analysis in a bifurcated artery system subjected to stenosis, magnetohydrodynamic (MHD) flow and aneurysm conditions. The findings of this study offer significant insights into the intricate interplay encompassing electro-osmosis, MHD flow, microorganisms, Joule heating and the ternary hybrid nanofluid.

The governing equations are first non-dimensionalised, and subsequently, a coordinate transformation is used to regularise the irregular boundaries. The discretisation of the governing equations is accomplished by using the Crank–Nicolson scheme. Furthermore, the tri-diagonal matrix algorithm is applied to solve the resulting matrix arising from the discretisation.

The investigation reveals that the velocity profile experiences enhancement with an increase in the Debye–Hückel parameter, whereas the magnetic field parameter exhibits the opposite effect, reducing the velocity profile. A comparative study demonstrates the velocity distribution in Au-CuO hybrid nanofluid and Au-CuO-GO ternary hybrid nanofluid. The results indicate a notable enhancement in velocity for the ternary hybrid nanofluid compared to the hybrid nanofluids. Moreover, an increase in the Brinkmann number results in an augmentation in entropy generation.

This study investigates the flow characteristics and entropy analysis in a bifurcated artery system subjected to stenosis, MHD flow and aneurysm conditions. The governing equations are non-dimensionalised, and a coordinate transformation is applied to regularise the irregular boundaries. The Crank–Nicolson scheme is used to model blood flow in the presence of a ternary hybrid nanofluid (Au-CuO-GO/blood) within the arterial domain. The findings shed light on the complex interactions involving stenosis, MHD flow, aneurysms, Joule heating and the ternary hybrid nanofluid. The results indicate a decrease in the wall shear stress (WSS) profile with increasing stenosis size. The MHD effects are observed to influence the velocity distribution, as the velocity profile exhibits a declining nature with an increase in the Hartmann number. In addition, entropy generation increases with an enhancement in the Brinkmann number. This research contributes to understanding fluid dynamics and heat transfer mechanisms in bifurcated arteries, providing valuable insights for diagnosing and treating cardiovascular diseases.