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The response of remittances inflows to asymmetric oil price shocks in Egypt
Purpose
The purpose of this paper is to explore and analyse the dynamic relationship between remittances inflows of Egyptians working abroad and asymmetric oil price shocks.
Design/methodology/approach
This study uses a vector autoregressive (VAR) model to explain the impulse response functions (IRFs) and the forecast error variance decomposition (FEVD). The rationale behind using these tools is its ability to examine the dynamic effects of our variables of interest.
Findings
The impulse response functions confirmed that remittance inflows have various responses to asymmetric oil price shocks. For instance, inflowing remittances increase in response to positive oil price shocks, while it decreases in response to negative oil price shocks. Also, the results indicate that the responses are significant in the short and medium-run and insignificant in the long run. The magnitude of these responses reaches its peak or trough in the third year. Further, the variance decomposition reveals that oil price decreases are more influential than oil price increases.
Originality/value
This means that remittances inflows in Egypt are pro-cyclical with oil price shocks. That explained by the fact that more than one-half of those remittances sent from GCC countries where real economic growth is very pro-cyclical with the oil prices. This empirical assessment will help policymakers to determine the behaviour of remittances and highlights the impact of different kinds of oil prices shocks on remittances. Unlike the little existing literature, this study is the first study applied the VAR model using a novel dataset spanning 1960-2016
Impulse Response with Correlation Study of a Broadband Bended Wearable Monopole Antenna
In this paper, the impulse response of a wide band flexible circular monopole antenna is presented. The antenna is fabricated on liquid crystalline polymer flexible substrate with a compact geometry that makes it suitable for wearable applications under different bending conditions. The antenna is fed by coplanar waveguide transmission line and has a compact total size of 40 × 22 mm2. The presented antenna has a good performance over the operating frequency range for straight and bent configurations. The design principals, simulation and experimental results are presented in this work
Generalized ψ
The aim of this work is to introduce ψ-operations on fuzzy topological spaces and to use them to study fuzzy generalized ψρ-closed sets and fuzzy generalized ψρ-open sets. Also, we introduce some characterizations and properties for these concepts. Finally we show that certain results of several publications
on the concepts of weakness and strength of fuzzy generalized closed sets are considered as corollaries of the results of this research
Systematic Collective e-Cheating in a Saudi Arabian Higher Education Context: A Case Study
Objectives: The primary purpose was to investigate organized group cheating in a Middle Eastern institution during the shift to e-learning brought on by the COVID-19 pandemic in 2019.
Method: The study explores the personal experiences of ten Saudi Arabian English as a Foreign Language program graduates in a higher education institution through in-depth interviews via qualitative interpretative phenomenological analysis. The study was guided by Ajzen’s theory of planned behavior.
Results: A novel type of misconduct coined systematic collective e-cheating was identified and discussed. In addition, insights on the causes and types of e-cheating in a Middle Eastern context were provided.
Conclusions: Academic misconduct was directly influenced by a rapid transition to e-learning, societal culture, and subjective norms, all of which jointly contributed to shifts in ethical perceptions leading to increased reports of cheating.
Objectives: The primary purpose was to investigate organized group cheating in a Middle Eastern institution during the shift to e-learning brought on by the COVID-19 pandemic in 2019.
Method: The study explores the personal experiences of ten Saudi Arabian English as a Foreign Language program graduates in a higher education institution through in-depth interviews via qualitative interpretative phenomenological analysis. The study was guided by Ajzen’s theory of planned behavior.
Results: A novel type of misconduct coined systematic collective e-cheating was identified and discussed. In addition, insights on the causes and types of e-cheating in a Middle Eastern context were provided.
Conclusions: Academic misconduct was directly influenced by a rapid transition to e-learning, societal culture, and subjective norms, all of which jointly contributed to shifts in ethical perceptions leading to increased reports of cheating.
Implication for Theory and/or Practice: Education professionals need to be aware of underlying issues related to unethical behavior and encourage students to understand and address negative ideologies regarding ethics on a societal level. Efforts must also be made to raise instructor awareness of academic misconduct in e-learning through comprehensive professional development programs. Furthermore, with the increased use of technology in education, if the social, cultural, and perceptional factors are not addressed, educational systems will be impacted, affecting the credibility and value of academic degrees should cheating become the norm
Mathematical analysis of HIV/HTLV-I co-infection model with saturated incidence rate
Direct contact with specific contaminated body fluids is how both the human immunodeficiency virus (HIV) and the human T-lymphotropic virus type I (HTLV-I) are transmitted from one person to another. Therefore, the two viruses can co-infect same person. In the literature all the HIV/HTLV-I co-infection models assume that the infection rate is given by bilinear incidence. However, for high concentration of pathogens, the bilinear incidence is not suitable. Therefore, this study will focus on the dynamical behavior of an HIV/HTLV-I co-infection model with saturated incidence. The model includes the effect of Cytotoxic T lymphocytes (CTL) immune response. Through the non-negativity and boundedness of the solutions, we demonstrated that our proposed model is biologically acceptable. We calculate the threshold parameters which determine when the equibrium point exists and when it is globally asymptotically stable. Utilizing the Lyapunov function and Lyapunov-LaSalle asymptotic stability, we demonstrate the global asymptotic stability of all equilibrium. We performed numerical simulations to confirm the analytical solutions. The effect of saturation on The dynamics of HIV/HTLV-I co-infection are discussed
Uavs enhanced navigation in outdoor gnss denied environment using UWB and monocular camera systems
Cooling Rate and Fibrous Type Striated Deformations Effects on the Mechanical Properties of Sn 8.6 wt. % Zn Alloy
Sn-Zn alloy has been taken as one of the most important lead free solder alloys due to the toxicity and the alpha radiation of lead impurities. The influence of cooling rate on the mechanical and structural properties of Sn ndash 8.6 wt. % Zn lead free solder alloy was studied.nbsp The microstructure of the quenched and slowly cooled samples of Sn ndash Zn alloy was examined by X ndash rays analysis and Scanning electron microscopy (SEM). There is an appearance of fibrous type striated deformations on the surfaces of the quenched samples more than those on the surfaces of the slowly cooled samples. The hardening parameters were obtained through stress-strain relations in the temperature range 333-393K for slowly cooled and quenched samples. The quenching samples indicated an improvement in the mechanical properties. The energy activated the rate controlling mechanisms has been calculated and found to be 17.85 and 24.57 kJ/mol for slowly cooled and quenched samples respectively. These values were found to be close to those reported for the grain boundary sliding mechanism in Sn-based alloys.nbs
Generalized ψρ-Operations on Fuzzy Topological Spaces
The aim of this work is to introduce ψ-operations on fuzzy topological spaces and to use them to study fuzzy generalized ψρ-closed sets and fuzzy generalized ψρ-open sets. Also, we introduce some characterizations and properties for these concepts. Finally we show that certain results of several publications on the concepts of weakness and strength of fuzzy generalized closed sets are considered as corollaries of the results of this research. Preliminaries The concept of fuzzy topology was first defined in 1968 by Chang 1 based on the concept of a fuzzy set introduced by Zadeh in 2 . Since then, various important notions in the classical topology such as generalized closed, generalized open set, and weaker and stronger forms of generalized closed and generalized open sets have been extended to fuzzy topological spaces. The purpose of this paper is to introduce and study the concept of ψ-operations, and by using these operations, we will study fuzzy generalized ψρ-closed sets and fuzzy generalized ψρ-open sets in fuzzy topological spaces. Also, we show that some results in several papers 3-15 considered as corollaries from the results of this paper. Let X, τ be a fuzzy topological space fts, for short , and let μ be any fuzzy set in X. We define the closure of μ to be Cl μ ∧{λ | μ ≤ λ, λ is fuzzy closed} and the interior of μ to be Int μ ∨{λ | λ ≤ μ, λ is fuzzy open}. A fuzzy point x r 16 is a fuzzy set with support x and value r ∈ 0, 1 . For a fuzzy set μ in X, we write x r ∈ μ if and only if r ≤ μ x . Evidently, every fuzzy set μ can be expressed as the union of all fuzzy points which belongs to μ. A fuzzy point x r is said to be quasicoincident 17 with μ denoted by x r qμ if and only if r μ x > 1. A 2 Abstract and Applied Analysi
Cytotoxic and antioxidant properties of active principals isolated from water hyacinth against four cancer cells lines
BACKGROUND: Eichhornia crassipes (Mart) solms is an invasive macrophyte causing serious problems to the network of irrigation and drainage canals in the Nile Delta region. The present study aim to evaluate the potential anticancer and antioxidant activities of Eichhornia crassipes crude extract and its pure compounds. METHODS: The macrophyte was collected from El-Zomor canal, River Nile (Egypt), cleaned, air dried, grinded then extracted with methanol (crude extract). The extract was fractionated using pre-coated silica gel plates (TLC F(254)) with hexane/ethyl acetate (8.5: 1.5 v/v) as mobile phase. Nine fractions were separated (A-I) then scratched, eluted with the same mobile phase, filtered and the separated fractions were determined and identified using spectroscopic methods (Mass spectrum (MS), Infra red (IR) and Proton H-Nuclear magnetic resonance (H-NMR). Both the crude extract and its nine identified compounds were tested for their antioxidant (using 2, 2 diphenyl-1-picrylhydrazyl (DPPH), 2, 2′- azino-bis {ethylbenzthiazoline-6-sulfonic acid (ABTS(.))} methods) and anticancer activity (using MCF-7, HeLa, Hep.G2 and EACC cell lines). RESULTS: The antioxidant and anticancer activities of the crude extract exhibited the highest effect while the compounds showed variable effects which depend on the type of compound and cancer cell line. The antioxidant activity of the crude extract exhibited the highest followed in descending order by compounds D, E, G and H respectively. Concerning the anticancer potency, the crude extract showed also the highest effect while the identified compounds (A, B, C, D, E, F, G, H and I) showed variable anticancer activities against the four different cell lines. In addition, Compound I exhibited the most potent anticancer activity against HepG2 cell line while compound D exhibited high anticancer activity against HeLa cells and EACC. The results revealed the presence of different compounds (Alkaloids and terpenoids) with variable antioxidant and anticancer activities which elicited an auto-augmentation in the crude extract leading to its greatest activities. The action of the identified anticancer compounds on DNA fragmentation was studied. CONCLUSION: The study illustrated the potential of Eichhornia as a valuable resource for natural compounds of desirable medicinal properties (e.g. antioxidants and anticancer)
Oxidative Leaching Kinetics of Vanadium from Egyptian Boiler Ash under Acidic Oxidizing Conditions
Processing of Egyptian boiler ash in sulphuric acid solution using hydrogen peroxide as oxidant has been investigated. The results showed that leaching temperature, hydrogen peroxide, sulphuric acid concentration, leaching time, liquid-to-solid ratio and agitation speed, have significant effect; optimum process operating parameters were established as follows: temperature: 9
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