<p>The objective of this paper is to study the dynamical behavior of an aquatic food web system. A mathematical model that includes nutrients, phytoplankton and zooplankton is proposed and analyzed. It is assumed that, the phytoplankton divided into two compartments namely toxic phytoplankton which produces a toxic substance as a defensive strategy against predation by zooplankton, and a nontoxic phytoplankton. All the feeding processes in this food web are formulating according to the Lotka-Volterra functional response. This model is represented mathematically by the set of nonlinear differential equations. The existence, uniqueness and boundedness of the solution of this model are investigated. The local and global stability conditions of all possible equilibrium points are established. The occurrence of local bifurcation and Hopf bifurcation are investigated. Finally, numerical simulation is used to study the global dynamics of this model.</p>
Novel has recently received the attention of readers and writers greatly, because of the role they play, and this indicates an important rule, which is whenever there is an art or creativity, there must be a respective criticism, and this criticism is certainly not less important than the author. So there are critics who have a prestigious literary position in the follow-up story development, and trying to describe the transformation of its elements. One of these critics is professor Fadhel Thamer, and who wants to approach one of the elements of the novel exploring, must stop on the visions of this critic about it , and that’s why we take the (character) element following the most important opinions of this critic about
... Show MoreThe nation-building process in fragile states is complex, often involving multifaceted challenges and opportunities. A pertinent example is Iraq post-2003, which serves as a model to study the intricacies of rebuilding a nation in the aftermath of conflict. During this period, we witnessed a significant international intervention aimed at establishing democratic governance, fostering economic development, and restoring social stability. Iraq’s nation-building journey showcases both successes and shortcomings. Establishing a representative government marked a step towards inclusivity and political participation, yet sectarian tensions persisted, hindering cohesive national identity. Economic initiatives aimed to harness Iraq's oil resou
... Show MoreAbstract Candida albicans is a commensal fungal pathogen that grows in yeast and hyphal forms in the human gut. C. albicans causes mucosal and cutaneous diseases that can result in significant mortality following systematic infections and it also exhibits drug resistance. Zebrafish have been an excellent model to investigate C. albicans infections because of their transparency and the availability of many transgenic lines. However, there is a limitation in using zebrafish as a model because the fish embryos cannot survive at 37°C therefore it is not suitable for studying Candida infections at physiological relevant human body temperature. In this thesis, the normal embryonic development of Arabian killifish (A. dispar) is investigated, rev
... Show MoreThe novel has recently received great attention from readers and before them writers, due to the role it is playing, and this indicates an important rule, which is whenever there is art or creativity, there must be a criticism of its own, and this criticism is certainly no less important than its owner, so we find There are critics who have their distinguished literary position in following up the narrative development, and trying to describe the transformation of its elements, including Professor Fadel Thamer, and whoever wants to approach an element of the novel as an explorer, he must stand on the visions of this critic about it, and this is what made us take the element (personality) Tracking the most important opinions of the critic
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In this article we study a single stochastic process model for the evaluate the assets pricing and stock.,On of the models le'vy . depending on the so –called Brownian subordinate as it has been depending on the so-called Normal Inverse Gaussian (NIG). this article aims as the estimate that the parameters of his model using my way (MME,MLE) and then employ those estimate of the parameters is the study of stock returns and evaluate asset pricing for both the united Bank and Bank of North which their data were taken from the Iraq stock Exchange.
which showed the results to a preference MLE on MME based on the standard of comparison the average square e
... Show MoreThe current research seeks to identify the impact of Barman's model on acquisition of the concepts of jurisprudence of worship among students of the departments of Qur'anic sciences. To achieve the research objectives, the researcher relied on the experimental method through a design with partial control by relying on two experimental groups receiving teaching by using the Barman model and a control group receives teaching through the normal method. After applying the experiment, the study reached the following results: Students of the Department of Qur’anic Sciences in general need educational programs linked to the curriculum and built on scientific foundations, according to their needs and problems (psychological, cognitive, and soc
... Show MoreIn this research, we sought to identify the nature of the relationship between the exchange rate of the Chinese yuan and the value of Chinese exports, through the formulation of a standard model based on the model of common integration, and based on the data of the study and using the test "Angel-Granger" It reflects the relationship between the two research variables, through which the relationship between the RMB exchange rate and the value of Chinese exports was estimated during the period 1978-2017.
This research is concerned with studying (the concept of freedom in the texts of Yaşar Kamal the play), as the Turkish playwright (Kamal Yasar) is one of the contemporary playwrights who have been interested in and criticize society, and perhaps the concept of freedom in his texts took a different form, through his ability to renew and present his attempts to create A theatrical form different from his earlier writers in dealing with the life of the peasants and the oppression that went through them, as the researcher identified the problem of his research with the following question: What is the concept of freedom in the texts of Yashar Kamal? The research aims to define the concept of freedom in the texts of Yashar Kamal of the play,
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