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The Dynamics of a Tritrophic Leslie-Gower Food-Web System with the Effect of Fear
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The avoidance strategy of prey to predation and the predation strategy for predators are important topics in evolutionary biology. Both prey and predators adjust their behaviors in order to obtain the maximal benefits and to raise their biomass for each. Therefore, this paper is aimed at studying the impact of prey’s fear and group defense against predation on the dynamics of the food-web model. Consequently, in this paper, a mathematical model that describes a tritrophic Leslie-Gower food-web system is formulated. Sokol-Howell type of function response is adapted to describe the predation process due to the prey’s group defensive capability. The effects of fear due to the predation process are considered in the first two levels. It is assumed that the generalist predator grows logistically using the Leslie-Gower type of growth function. All the solution properties of the model are studied. Local dynamics behaviors are investigated. The basin of attraction for each equilibrium is determined using the Lyapunov function. The conditions of persistence of the model are specified. The study of local bifurcation in the model is done. Numerical simulations are implemented to show the obtained results. It is watched that the system is wealthy in its dynamics including chaos. The fear factor works as a stabilizing factor in the system up to a specific level; otherwise, it leads to the extinction of the predator. However, increasing the prey’s group defense leads to extinction in predator species.

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Publication Date
Sun Dec 25 2022
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Epicatechin product of Camellia sinensis leaves detection by thin layer chromatography and high performance liquid chromatography
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The current study performed in order to detect and quantify epicatechin in two tea samples of Camellia sinensis (black and green tea) by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Extraction of epicatechin from black and green tea was done by using two different methods: maceration (cold extraction method) and decoction (hot extraction method). Qualitative and quantitative determinations of epicatechin in two tea samples were investigated. Epicatechin identification was made by utilizing preliminary chemical tests and TLC. This identification was also boosted by HPLC and then quantified epicatechin in all ethyl acetate fractions of two tea samples. This research revealed the existence of epica

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Publication Date
Wed Jun 19 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Disclosure of deferred taxes according to IAS-12: بحث تطبيقي في الهيئة العامة للضرائب قسم الشركات
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The research aims to clarify the importance of adoption of International Accounting  Standard No. (12) "Income Taxes" as a tool for the measurement and disclosure of income taxes in the financial statements، and how to deal with the differences that arise as a result of difference in net profit accounting for net tax profit ،The problem of the research focused on the disparity between the income tax estimate in Iraq in accordance with the accounting standards and financial reporting and assessment of income tax in accordance with the tax laws and legislation, this discrepancy has led to the emergence of differences between accounting profit and tax profit (temporary differences and permanent differences) and these differences of w

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Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
An Environmental Study of Epiphytic Algae on Ceratophyllum demersum in Tigris River within Baghdad City, Iraq
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The present study was conducted in the Tigris River within Baghdad (University of Baghdad campus). The study included some physicochemical parameters and qualitative of epiphytic algae on the host plant (Ceratophyllum demersum) during summer season 2013. The results revealed that the study area was alkaline, hard and oxygenated water. A total of 105 taxa of epiphytic algae was identified. Bacillariophyceae diatoms composed 44.7% of the total and were represented by 42.4% of the order Pennales and 1.9 %of the order Centrales. Chlorophyceae composed 32.3%, followed by Cyanophyceae composed 22.8 % of the total. The total number of epiphytic algae was fluctuated among the study period. Most of the identified algae were benthos type and a few

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Publication Date
Tue Dec 01 2020
Journal Name
Malaysian Journal Of Biochemistry & Molecular Biology
ANTIBACTERIAL AND ANTIBIOFILM EFFECTS OF BISMUTH NANOPARTICLES PRODUCED BY BACILLUS SUBTILIS AGAINST MULTIDRUG-RESISTANT Pseudomonas aeruginosa
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This study aimed to determine the effect of green bismuth oxide (BiO) NPs against multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) from wound infections. Among 450 wound samples collected from patients admitted to the hospital, 200 P. aeruginosa isolates were identified. MDR strains of P. aeruginosa were detected by disc diffusion method. BiO NPs were synthesized using wild Bacillus subtilis (B. subtilis) strain and infrared spectroscopy, X-ray diffraction and scanning electron microscopy techniques. The antibacterial effect of the NPs compared to antibiotics against MDR strains was evaluated using a standard disk diffusion method. BiO NPs were synthesized at 0.005 M concentration of solution. According to the SEM im

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Publication Date
Sat Aug 01 2020
Journal Name
Nanotechnology For Environmental Engineering
Synthesis of Ni@γ-Al2O3@PID\SiW recyclable nanocatalyst and its catalytic reduction and antibacterial activities
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Publication Date
Sun Mar 13 2011
Journal Name
Baghdad Science Journal
Intracellular and Extracellular extracts activity of Oscillatoria limnetica and Chroococus minor against some Bacteria and Fangi
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In this study Oscillatoria limnetica and Chroococus minor were isolated ?purified and identification from water canal around Baghdad University Campus. The water of this canals originally from Tigris River. BG-11 culture media was used for their cultivation in suitable laboratory conditions (25c°, 200µE/m2/sec) for 16:8 hrs. Light: dark. Each culture was harvested at the end of exponential phase .Organic solvents used for extraction were Ethanol? Hexane and Methanol 95% to extract the crude active Intracellular and Extracellular substances, and evaporated down to dryness .Antibacterial and antifungal activity of these different extracts were evaluated against 6 strains of gram positive bacteria and gram negative bacteria in additi

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Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Synthesis, Characterization and Biological Activity Evaluation of Some Pyrazoles, Thiazoles and Oxazoles Derived from 2-Mercaptoaniline
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    Synthesis of 2-mercaptobenzothiazole (A1) is performed from the reaction of  o-aminothiophenol and carbon disulfide CS2 in ethanol under basic condition. Compound (A1)  is reacted with chloro acetyl chloride to give compound (A2). Hydrazide acid compound (A3) is obtained from the reaction of compound (A2) with  hydrazine hydrate in ethanol under reflux in the presence of glacial acetic acid .The reaction of hydrazide acid compound (A3) with ethyl acetoacetate gives pyrazole compound (A4). The new hydrazone  compound (A5) was prepared from the reaction of compound (A3) with  benzaldehyde. Reaction of compound

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Solving Optimal Control Linear Systems by Using New Third kind Chebyshev Wavelets Operational Matrix of Derivative
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In this paper, a new third kind Chebyshev wavelets operational matrix of derivative is presented, then the operational matrix of derivative is applied for solving optimal control problems using, third kind Chebyshev wavelets expansions. The proposed method consists of reducing the linear system of optimal control problem into a system of algebraic equations, by expanding the state variables, as a series in terms of third kind Chebyshev wavelets with unknown coefficients. Example to illustrate the effectiveness of the method has been presented.

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Publication Date
Sat Nov 30 2024
Journal Name
Research Journal Of Chemistry And Environment
Evaluation of blue textile dye decolorization by immobilized polyphenol oxidase using pumice stone under optimum conditions
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Industrial dyes are major pollutants in wastewater and river water with an initial visible concentration of 1 mg/L. Recent studies have shown the possibility of using polyphenol oxidase in catalytic biological treatment due to its ability to oxidize a large number of dyes and pollutants in wastewater and the flexibility to work in wide ranges of temperature, pH and salinity. It is easy availability as well as the low economic cost resulting from its use in biological treatments, this enzyme polyphenol oxidase was used. The findings in this study showed that the extraction of polyphenol oxidase (PPO) from potato peel was homogenized with potassium phosphate buffer (0.1 M, pH 7) at a ratio of 1:10 (weight: volume) for two min. The res

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Publication Date
Wed Oct 12 2011
Journal Name
Journal Of Liquid Chromatography & Related Technologies
RAPID DETERMINATION OF SPHINGANINE AND SPHINGOSINE IN URINE BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY USING MONOLITHIC COLUMN
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A rapid high performance liquid chromatography method for the determination of sphinganine (Sa) and sphingosine (So) in urine samples by employing a silica-based monolithic column is described. The samples were first extracted using ethyl acetate and derivatized using ortho-phthaldialdehyde in the presence of 2-mercaptoethanol. C20 sphinganine was used as internal standard. Under the optimized conditions, separation was achieved using a mixture of methanol:water (93:7, v/v), column temperature at 30°C, flow rate of 1 mL min−1, and an injection volume of 10 μL. Good linearity was obtained for Sa and So over the concentration range 20–500 ng mL−1(correlation coefficients ≥0.9978). The detection limits were 0.45 ng mL−1 for Sa and

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