It is well known that the spread of cancer or tumor growth increases in polluted environments. In this paper, the dynamic behavior of the cancer model in the polluted environment is studied taking into consideration the delay in clearance of the environment from their contamination. The set of differential equations that simulates this epidemic model is formulated. The existence, uniqueness, and the bound of the solution are discussed. The local and global stability conditions of disease-free and endemic equilibrium points are investigated. The occurrence of the Hopf bifurcation around the endemic equilibrium point is proved. The stability and direction of the periodic dynamics are studied. Finally, the paper is ended with a numerical simulation in order to validate the analytical results.
Background: Lung cancer is responsible for the most
cancer deaths in both men and women throughout the
world. Deaths from lung cancer (160,440 in 2004,
according to the National Cancer Institute) exceed the
number of deaths from four other major cancers combined
(breast, colon, pancreatic and prostate).
Objective: To assess the behavior and the approaches of
lung cancer in a sample of Iraqi patients.
Methods: This descriptive retrospective study was
performed using the records of 390 patients proved to have
lung cancer that had attending the Thoracic Surgery
Department of Surgical Specialties Hospital-Medical City
\Baghdad for the period from January, 1st
, 2001 to
December, 31st
,2002.
Res
Oil pollution of the soil due to a leakage in oil tubes, transportation of products, or during oil excavations can change the soil physical and mechanical, chemical, and biological properties. Consequently, the soil may or may not be eligible for engineering construction projects and it may need a significant treatment. Therefore, it is required to have a better understanding of the general behavior and the corresponding geotechnical properties upon pollution particularly for those areas associated with oil explorations and industry like Thi-Qar Governorate. Fine and coarse soils from two sites at the University of Thi-Qar are artificially contaminated with oil products ranging from 0% to 10% of their dry weight. Testing programs have been
... Show MoreBackground: The aims of this study were to evaluate the effect of implant site preparation in low-density bone using osseodensification method in terms of implant stability changes during the osseous healing period and peri-implant bone density using CBCT. Material and methods: This prospective observational clinical study included 24 patients who received 46 dental implants that were installed in low-density bone using the osseodensification method. CBCT was used to measure the bone density pre- and postoperatively and implant stability was measured using Periotest® immediately after implant insertion and then after 6 weeks and 12 weeks postoperatively. The data were analyzed using paired t-test and the probability value <0.05 was conside
... Show MoreThis paper contains an equivalent statements of a pre- space, where are considered subsets of with the product topology. An equivalence relation between the preclosed set and a pre- space, and a relation between a pre- space and the preclosed set with some conditions on a function are found. In addition, we have proved that the graph of is preclosed in if is a pre- space, where the equivalence relation on is open.
On the other hand, we introduce the definition of a pre-stable ( pre-stable) set by depending on the concept of a pre-neighborhood, where we get that every stable set is pre-stable. Moreover, we obtain that
... Show MoreThis essay aims to highlight the most important issues and difficulties facing implementing large projects that follow the turn-key method, considered one of the types of contractual methods in Iraq, especially for large and complex projects requiring speedy completion. The projects implemented in this way face delays and delays in completion, which led to the lack of benefit from the projects for which they were implemented, especially those affecting the lives of citizens within the health sector. The case study dealt with the construction of hospitals with multi-bed capacities within multiple governorates in Iraq, With large financial allocations within the federal budget of the Government of Iraq over several years.
... Show MoreThe present study aims to test a range of hypotheses about the effectiveness of each of the theory of transactional leadership, and the theory of transformational leadership in the Egyptian environment, and to identify any of them are better able to predict the effectiveness of leadership. And after the effect will be to identify the quality of the relationship between the leader and the subordinate in leadership , and what is the role of transformational leadership dimensions influencing the effectiveness of leadership. The field study was conducted on a sample of companies' public and private sector and the government in Egypt. The results of the study resulted in experimental that transacti
... Show MoreToday, the role of cloud computing in our day-to-day lives is very prominent. The cloud computing paradigm makes it possible to provide demand-based resources. Cloud computing has changed the way that organizations manage resources due to their robustness, low cost, and pervasive nature. Data security is usually realized using different methods such as encryption. However, the privacy of data is another important challenge that should be considered when transporting, storing, and analyzing data in the public cloud. In this paper, a new method is proposed to track malicious users who use their private key to decrypt data in a system, share it with others and cause system information leakage. Security policies are also considered to be int
... Show MoreThis paper presents a minimum delay congestion control in differentiated Service communication networks. The premium and ordinary passage services based fluid flow theory is used to build the suggested structure in high efficient manage. The established system is capable to adeptly manage both the physical network resource limitations and indefinite time delay related to networking system structure.
In this work we reported the synchronization delay in
semiconductor laser (SL) networks. The unidirectional
configurations between successive oscillators and the correlation
between them are achieved. The coupling strength is a control
parameter so when we increase coupling strength the dynamic of the
system has been change. In addition the time required to synchronize
network components (delay of synchronization) has been studied as
well. The synchronization delay has been increased by mean of
increasing the number of oscillators. Finally, explanation of the time
required to synchronize oscillators in the network at different
coupling strengths.