Understanding the effects of fear, quadratic fixed effort harvesting, and predator-dependent refuge are essential topics in ecology. Accordingly, a modified Leslie–Gower prey–predator model incorporating these biological factors is mathematically modeled using the Beddington–DeAngelis type of functional response to describe the predation processes. The model’s qualitative features are investigated, including local equilibria stability, permanence, and global stability. Bifurcation analysis is carried out on the temporal model to identify local bifurcations such as transcritical, saddle-node, and Hopf bifurcation. A comprehensive numerical inquiry is carried out using MATLAB to verify the obtained theoretical findings and understand the effects of varying the system’s parameters on their dynamical behavior. It is observed that the existence of these factors makes the system’s dynamic behavior richer, so that it involves bi-stable behavior.
In this study, vegetable tanned leather waste of cow (VTLW-C) is used as adsorbent for removing methyl violet 10B dye from aqueous solution. The VTLW-C adsorbent was characterized by FTIR and SEM in order to evaluate its surface properties before using in adsorption experiments. Batch adsorption method was applied to study the effect of different factors such as weight of leather waste, time of shaking, and starting concentration of methyl violet 10B dye. Different isothermal models such as Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D–R) were used to analyze the experimental data. Kinetic study proceeds using (PFO) kinetic model and (PSO) kinetic model. The results showed better agreement with the Freundlich model; this means
... Show MoreThe flavonoglycone hesperidin is recognized as a potent anti-inflammatory, anticancer, and antioxidant agent. However, its poor bioavailability is a crucial bottleneck regarding its therapeutic activity. Gold nanoparticles are widely used in drug delivery because of its unique properties that differ from bulk metal. Hesperidin loaded gold nanoparticles were successfully prepared to enhance its stability and bioactive potential, as well as to minimize the problems associated with its absorption. The free radical scavenging activities of hesperidin, gold nanoparticles, and hesperidin loaded gold nanoparticles were compared with that of Vitamin C and subsequently evaluated in vitro using 2,2-diphenyl-1-picrylhydrazyl assay. The antioxi
... Show MoreThis study tries to examine a model involving human resources management practices, employees’ outcomes, governmental support, and organizational performance of small businesses in Malaysia. It was hypothesized that HRM practices will be positively related to the organizational performance (financial and operational), and that employees’ outcomes would serve as a mediator in the relationship between HRM practices and performance. Also it was hypothesized that the governmental support will be positively related to organizational performance. The statistical results on data gathered from a sample of 265 small manufacturing businesses will demonstrate the nature of relationships among the study variables. Theoretical and practical
... Show MoreMost of the studies conducted in the past decades focused on the effect of interest rates and exchange rates on domestic investment under the assumption that the independent variables have the same effect on the dependent variable, but there were limited studies that investigated the unequal effects of changes in interest rates and exchange rates, both positive and negative, on domestic investment. This study used a nonlinear autoregressive distributed lag (NARDL) model to assess the unequal effects of the real interest rate and real exchange rate variables on domestic investment in Egypt for the period 1976 - 2020. The results revealed that positive and negative shocks for both exchange rates have unequal effects on
... Show MoreBaghdad is considered the largest city in Iraq, with a population of approximately nine million people, according to the 2022 statistics. Due to this population increase, the city of Baghdad has experienced horizontal expansion rather than vertical expansion, resulting in a shortage of basic services, an increase in population migration, and a rise in prices. Therefore, our research focuses on shedding light on the patterns of population concentrations in the city of Baghdad and the nature of population distribution within it. We addressed the topic from various angles, starting with the population distribution among the city's districts and their density. Additionally, we explored the factors influencing population density in the province
... Show MoreElectro-kinetic remediation technology is one of the developing technologies that offer great promise for the cleanup of soils contaminated with heavy metals. A numerical model was formulated to simulate copper (Cu) transport under an electric field using one-dimensional diffusion-advection equations describing the contaminant transport driven by chemical and electrical gradients in soil during the electro-kinetic remediation as a function of time and space. This model included complex physicochemical factors affecting the transport phenomena, such as soil pH value, aqueous phase reaction, adsorption, and precipitation. One-dimensional finitedifference computer program successfully predicted meaningful values for soil pH profiles and Cu
... Show MoreThis study is marked by: The ignorant poem and body language
Its main objective is to reveal the manifestations of this language in the text mentioned, and accordingly, the sieve poem has been read semantic (semantic) and hermeneutic, revealing the poet's ability to employ symbols and signals (body language) in the poem chosen for this purpose; The existence of such language in pre-Islamic poetry. After a long reflection and reading, the signs and symbols of the physical movement of the body, and its feminine and aesthetic manifestations were identified, and this was achieved through the use of modern critical methodologies that directly affect this language. The study consisted of an introduction and three topics, followed by t
The surplus glycerol produced from biodiesel production process as a by-product with high quantity can be considered as a good source to prepare glycerol carbonate (GC) whereas with each 1000 kg from biodiesel obtains 100 kg from glycerol. Glycerol converted to glycerol carbonate over bio-char as a catalyst prepared by slow pyrolysis process under various temperatures from 400 ᴼC to 800 ᴼC. The char prepared at 700 ᴼC considered as a best one between the others which was manufactured to activate the transesterification reaction. GC have large scale of uses such as liquid membrane in gas separation, surfactants ,detergents , blowing agent , in plastics industry, in Pharmaceutical industry and electrolytes in lithium batteries.
... Show MoreObjectives: The study objectives were to evaluate customer satisfaction with community pharmacy services and measure the relationships between customer satisfaction and pharmacy/pharmacist characteristics and customer quality of life. Methods: This was a cross-sectional survey of a convenience sample of customers at 20 community pharmacies in 10 different geographical areas in Baghdad city between May and September 2018. We used the satisfaction items which were developed by Paterson and colleagues in 2013. The survey also assessed customer quality of life (QoL) with 12 QoL items. Results: The study recruited 400 pharmacy customers. Overall, customers reported good satisfaction with community pharmacy services. The most
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