Oscillation criteria are obtained for all solutions of the first-order linear delay differential equations with positive and negative coefficients where we established some sufficient conditions so that every solution of (1.1) oscillate. This paper generalized the results in [11]. Some examples are considered to illustrate our main results.
The logistic regression model is an important statistical model showing the relationship between the binary variable and the explanatory variables. The large number of explanations that are usually used to illustrate the response led to the emergence of the problem of linear multiplicity between the explanatory variables that make estimating the parameters of the model not accurate.
... Show MoreThe examination of gills of the common carp Cyprinus carpio revealed the presence of two species of the family Trichodinidae belonging to the genus Dipartiella (Raabe, 1959) Stein, 1961 namely D. indiana Saha and Bandyopadhyay, 2017 and D. kazubski Mitra and Bandyopadhyay, 2009 for the first time in Iraq from Al-Graiat location on the Tigris River at Baghdad city. This also represents the first record of the genus Dipartiella from fishes of Iraq. The descriptions and measurements of these two parasite species as well as their illustrations were given.
Food fortification has an important and necessary role in compensating for the shortage of nutritional micronutrients, especially in developing and least developed countries. So, 12 samples of flour available in the local market, whether imported or locally produced flour, were obtained during 2019. The amount of base metal of the necessary iron element in the flour models studied which are available in local markets, measured by spot testing and was compared with the values that should be added according to the specification Iraqi standard. Results revealed the qualitative evaluation of iron in locally produced flour does not conform to the Iraqi standard and is almost free of any reinforcement. While the percentage of imp
... Show MoreThis study has contributed to understanding a delayed prey-predator system involving cannibalism. The system is assumed to use the Holling type II functional response to describe the consuming process and incorporates the predator’s refuge against the cannibalism process. The characteristics of the solution are discussed. All potential equilibrium points have been identified. All equilibrium points’ local stability analyses for all time delay values are investigated. The system exhibits a Hopf bifurcation at the coexistence equilibrium, which is further demonstrated. The center manifold and normal form theorems for functional differential equations are then used to establish the direction of Hopf bifurcation and the stability of the per
... Show MoreCeliac disease (CD) is an inflammatory small intestinal disorder that can lead to severe villous atrophy, and malabsorption . Since the measurement of α-amylase activity is the most widely used biochemical test for the diagnosis of pancreatic and non pancreatic disease , therefore serum α-amylase were studied in the present study in an attempt to evaluate the usefulness of this enzyme in the diagnosis of celiac disease and its relationship with anti gliadin IgA and IgG and serum glucose . Thirty one patients with celiac disease were studied and compared with twenty four healthy individuals . Significant elevation of α-amylase activity , glucose and anti gliadin IgA and IgG were observed in the sera of patients with celiac diseas
... Show MoreThe study aimed to reveal the extent of the first intermediate grade science curriculum focus on the national values, health, environmental, economic values, in the light of the education policy in the Kingdom of Saudi Arabia, in addition to present a proposed vision to strengthen it in the science curriculum for the first intermediate grade. The study was applied to the two books student and the two books of activity on the first-second semesters for the academic year 1441 AH. To analyze the curriculum content, the study used a verified card prepared by the researchers and a criterion for interpreting percentages. The study reached the following results: environmental values ranked first with a concentration of (43%), i.e. with an avera
... Show MoreBacterial resistance caused by antibiotic misuse has garnered substantial attention, prompting numerous researchers to develop materials that can combat these resistant pathogens. The hydrothermal method is employed to produce γ-MnO2 nanostars and to coat them with Fe2O3 nanoparticles. The materials are characterized using XRD, FE-SEM, EDX, and UV-vis spectrophotometry, as well as antioxidant and antibacterial activities. The nano γ-MnO2 star shapes are coated with tiny spherical Fe2O3 nanoparticles with diameters of 35-47 nm. The peaks located at the crystal planes (120), (031), (131), (230), (300), (160), (421), and (003) are represented by the values of 2θ = 22.36º, 34.36º, 37.22º, 38.78º, 42.56º, 56.14º, 65.48º and 68.
... Show MoreLevofloxacin belongs to the fluoroquinolone family; it is a potent broad-spectrum bactericidal agent. The pharmacophore required for significant antibacterial activity is the C-3 carboxylic acid group and the 4-pyridine ring with the C-4 carbonyl group, into which binding to the DNA bases occur. In this work, we tried to show that by masking the carboxyl group through amide formation using certain amines to form levofloxacin carboxamides, an interesting activity is kept. Levofloxacin carboxamides on the C-3 group were prepared, followed by the formation of their copper complexes. The target compounds were characterized by FT-IR, elemental analysis. The antimicrobial activity of the target compounds was evaluated and showed satisfactory resu
... Show More