Relation on a set is a simple mathematical model to which many real-life data can be connected. A binary relation on a set can always be represented by a digraph. Topology on a set can be generated by binary relations on the set . In this direction, the study will consider different classical categories of topological spaces whose topology is defined by the binary relations adjacency and reachability on the vertex set of a directed graph. This paper analyses some properties of these topologies and studies the properties of closure and interior of the vertex set of subgraphs of a digraph. Further, some applications of topology generated by digraphs in the study of biological systems are cited.
The resistance of Staphylococcus aureus to ciprofloxacin has complicated the problem of treating staphylococcal associated infections in which MRSA is the causative agent since ciprofloxacin was the drug of choice to treat such infections. Our study investigated the incidence of Ciprofloxacin resistant S. aureus isolates that were also methicillin resistant among Iraqi patients. The obtained bacterial isolates were tested for Ciprofloxacin resistance using agar dilution method and the sequence of gyrA and parC. The results revealed that about 8% of the isolated MRSA strains were Ciprofloxacin resistant and the resistance was due to mutation in gyrA rather than parC.
The present study attempts to shed light on some biological aspects and characteristics of Piaractus brachypomus, including some biometrics, phenotypic and feeding pattern that characterizes this species. Besides, the study touches upon the body shape and the Otolith. These fish species have recently been seen frozen in the Iraqi local market. The standard length of fish specimens in this study reach 26.55cm it exceeded the specimens of Pacu fish collected from other studies from other countries, As well the specimens weight was 632gm it exceeded other studies mentioned in this manuscript. As the irregularity in the distribution of teeth rows, especially in the lower jaw was clear in our specimens. The average weight of some skull b
... Show More
Abstract
The Holy Quran is the greatest motivator for the mind to keep pace with life. The doctrine of faith is a requirement of logic and wisdom, and it cannot be reached by the hand of superstition. The Qur’an destroyed the principle of superstition in the verses of the creation of the universe. The principle of inactivity of the Qur’an is a false accusation that collision with the texts of the Qur’an. The secret of scientific development is to harness the laws of nature, benefit from them, and walk according to its requirements, on which the manifestations of civilization and the Qur’an are based
... Show MoreAli AL-Gharbi area lies to the northeast of Missan Governorate, southeast of Iraq. The meteorological data recorded in Ali AL-Gharbi station for the period (1994-2014) were used to assess the climatic condition of the study area, it was found that the monthly mean of rainfall is (15.35 mm), relative humidity (43.95 %), the temperature (24.50 C◦), wind speed (4.35 m/sec) and the strongest and most frequent winds are the northwest, sunshine (8.54 h/day) and evaporation (305.73 mm).The results of the data analysis show that, the climate of study area is characterized by dry and relatively hot in summer, and cold with low rain in winter. This study shows that, there is water surplus of (35.69 %) of the total rainfall amount which is equivalen
... Show MoreOilwell cementing operations are crucial for drilling and completion, preserving the well's productive life. However, weak and permeable formations pose a high risk of cement slurry loss, leading to failure. Lightweight cement, like foamed cement, is used to avoid these difficulties. This study is focused on creating a range of foamed slurry densities and examining the effect of gas concentration on their rheological properties. The foaming agent and foam stabilizer are tested, and the optimal concentration is determined to be 2% and 0.12%, respectively, by the weight of the cement.
Furthermore, the construction of samples of foam cement with different densities (0.8, 1.0, 1.2, 1.4, and 1.6) g/cc is performed to f
... Show MoreBackground: Myasthenia gravis is an autoimmune disease of the neuromuscular junction that results in fluctuating muscle weakness as well as significant fatigue. Disease exacerbation is a critical condition, and the predisposing factors for it need to be identified to improve preventive measures.
Objectives: Our study aims to determine the predisposing factors for myasthenia gravis exacerbations in a group of Iraqi patients.
Subjects and Methods: A total number of 30 myasthenia gravis patients were admitted to the hospital with an exacerbation of their symptoms, determined as the development of functional disability, dysphagia, or respiratory fai
... Show MoreThe telescope works to magnify images of distant objects in general, but it needs special optical elements to complete the task to the fullest. The telescope needs optimal balance values of the optical parameters used to produce the best image, such as the effective focal length and the diameter of the pupil aperture, which are combined in a single concept called the focal number. The ground-based binary telescope relies on special lenses and an exceptional prism to achieve a hybrid design that produces clear images of relatively distant terrestrial objects. The pupil diameter of the telescope is relatively large to ensure that the largest possible amount of light is received, and as a result, a good image is obtained.
In this wo
... Show MoreIn this work, the effect of different particle size on the nonlinear optical properties of silver nanoparticles in de-ionized water was studied. The experimental observation of the far field diffraction patterns by CCD camera in two and three dimensions. The maximum change of nonlinear refractive index and the relative phase shift were calculated. The self-defocusing technique was used with a continuous-wave radiation from DPSS Blue laser .The wavelength is 473 nm with an output power of 270 mW. All the Ag colloids samples containing the sizes 15, 30, 50, and 70 nm of silver nanoparticles used in the study were chemically prepared. It was found that the nonlinear refractive index is a particle size dependent and of the order of 10-7 cm2/
... Show MoreThe dispersion of supported Pt and Pt–Ir reforming catalysts have been studied, after treatment with oxidative and reducing atmosphere. Methylcyclohexane dehydrogenation reaction in the absence of hydrogen was used as a test reaction. An attempt was made to relate the behavior of the catalysts upon subject to reaction, to the dispersion of the same type of catalysts upon treatment with similar atmosphere and temperatures which appeared in literature. The total conversion of reaction can be explained by a change in metal dispersion. Thus, methylcyclohexane dehydrogenation reaction appears to be a really “structure sensitive” reaction.
The toluene yield increases as the oxidation temperature i
... Show More