<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
... Show MoreIn this paper we prove that the planar self-assembling micelle system
has no Liouvillian, polynomial and Darboux first integrals. Moreover, we show that the system
has only one irreducible Darboux polynomial with the cofactor being if and only if via the weight homogeneous polynomials and only two irreducible exponential factors and with cofactors and respectively with be the unique Darbox invariant of system.
Polymers, being one of the most important materials in dentistry, offer great physical and mechanical qualities, as well as good biocompatibility. Aim of this study was done to evaluate the Polyetherketoneketone and Polyetherketoneketone polymer composite material used as dental implant through tensile strength, Fourier Transform Infrared analysis FTIR, and wettability). Polyetherketoneketone composites (Polyetherketoneketone and Strontium-containing hydroxyapatite) with selected weight percentage ratios of (0, 10%, 20%, 30%), were fabricated using a compression molding technique”, The study involved Samples preparation (sheets) shaped and form into the desired shape according to standard for tests which included tensile strength,
... Show MoreIn this study, isolated of Lactobacillus acidophilus were evaluated for their antipathogenic
bacterial activity. The antibacterial activity of the three isolated against
intestinal and food borne pathogenic bacteria in vitro was determined by Well's
Diffusion method, a total of three isolates of Lactobacillus acidophilus isolated from
ten different brands of traditional yoghurts showed a various antibacterial activity
against tested pathogenic bacterium, Cronobacter sakazakii isolated from stool
samples was more sensitive to the inhibition(23mm)inhibtion zone than were
Helicobacter pylori that isolated from stool samples (16mm) inhibtion zone and
Clostridium perfringens that isolated from stool samples (15mm). The
Background: Chronic periodontitis is an inflammatory disease of tissues supporting the teeth. Salivary compositions have been most intensely studied as a potential marker for periodontal disease. In this study, analysis of saliva provides a simple and non-invasive method of evaluating the role of salivary IgA (s-IgA) levels in periodontal disease by detecting the level of (s-IgA) in patients with chronic periodontitis smokers and non smokers patients and correlate the mean (s-IgA) levels with clinical periodontal parameters Plaque index (PLI) gingival index (GI), probing pocket depth (PPD) and clinical attachment level (CAL). Materials and Methods: The study samples consists of (15) patients with chronic periodontitis who were non smokers (
... Show MoreChina and India are considered both rising countries, and both are among the world's most populous and fastest growing economies. The long-term growth of both China and India has reinforced the importance of their bilateral relationship. The relations between China and India are complex, as relations between them have undergone great changes during the past seven decades, ranging from friendship to hostility. This study proceeds from the hypothesis that the nature and path of Sino-Indian relations after 2013 are affected by several factors and variables, some of which represent opportunities, others represent challenges and obstacles. Several opportunities have contributed to the reformulation of bilateral relations in terms of mutual ga
... Show MoreIn this work, we study two species of predator with two species of prey model, where the two species of prey live in two diverse habitats and have the ability to group-defense. Only one of the two predators tends to switch between the habitats. The mathematical model has at most 13 possible equilibrium points, one of which is the point of origin, two are axial, tow are interior points and the others are boundary points. The model with , where n is the switching index, is discussed regarding the boundedness of its solutions and the local stability of its equilibrium points. In addition, a basin of attraction was created for the interior point. Finally, three numerical examples were given to support the theoretical results.
Cadmium Oxide and Bi doped Cadmium Oxide thin films are prepared by using the chemical spray pyrolysis technique a glass substrate at a temperature of (400?C) with volumetric concentration (2,4)%. The thickness of all prepared films is about (400±20) nm. Transmittance and Absorbance spectra are recorded in the wave length ranged (400-800) nm. The nature of electronic transitions is determined, it is found out that these films have directly allowed transition with an optical energy gap of (2.37( eV for CdO and ) 2.59, 2.62) eV for (2% ,4%) Bi doped CdO respectively. The optical constants have been evaluated before and after doping.
Atopic dermatitis in another word Atopic Eczema is a chronic inflammatory skin disease that effecting all ages, described by lesions of eczematous and acute itch. As the objective of this study for determine the effect of variation in TSLP, IgE, and Eosinophil levels in patients with atopic dermatitis compared with a healthy control group. The level of TSLP was almost the same between the patients and the control group, and the reason was that most of the patients were treated with anti-allergic drugs. In this study, there is a significant (P = 0.004), serum level of TSLP in atopic dermatitis patient’s pre-treatment with immunotherapy (corticosteroids and antihistamines) is compared with atopic dermatitis patients’ post-tr
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