This paper treats the interactions among four population species. The system includes one mutuality prey, one harvested prey and two predators. The four species interaction can be described as a food chain, where the first prey helps the second harvested prey. The first and the second predator attack the first and the second prey, respectively, according to Lotka-Volterra type functional responses. The model is formulated using differential equations. One equilibrium point of the model is found and analysed to reveal a threshold that will allow the coexistence of all species. All other equilibrium points of the system are located, with their local and global stability being assessed. To back up the conclusions of the mathematical analysis, a numerical simulation examination of the model is carried out. The system's coexistence can be achieved as long as the harvesting rate of the prey population is lower than its intrinsic growth rate.
This study is considered the first effort of its kind in Iraq and in the Middle East towards studying the Marbled Teal Marmaronetta angustirostris that was carried on in Hor Al-Dalmaj, southern Iraq. The findings of this effort illustrate its importance as it paves the way for further study and observation for the bird and this important wetland itself. This study tackles the all possible aspects of the ecological and biological statuses of Marbled Teal (Threatened –Vulnerable bird species – IUCN Redlist) by means of field surveys and systematic monitoring that were conducted along the four seasons over the years 2013-2014 in one of the ecologically important and prominent and poorly-known wetlands in the
... Show MoreLaboratory model tests were performed to investigate the behavior of shallow and inclined skirted foundations placed on sandy soil with R.D%=30 and the extent of the impact of the positive and negative eccentric-inclined loading effect on them. To achieve the experimental tests, it was used a box of (600×600) mm cross-sectional and 600mm in height and a square footing of (50*50) mm and 10 mm in thickness attached to the skirt with Ds=0.5B and various an angle of (10°, 20°, 30°). The results showed that using skirts leads to a significant improvement in load-carrying capacity and decreased settlement. In addition, when the skirt angle increased, the ultimate load improved. Load-carrying capacity decreased with increasing eccentri
... Show MoreIn this contribution, new derivatives of bicyclic fused rings with bridgehead nitrogen of 3-substituted imidazo/pyrimidine derivatives A1-A3 were synthesized by reacting 2-aminobenzothiazol, acetyl acetone, and different substituted aldehydes in a one-pot reaction. These compounds A1-A3 were then condensed with 4-bromobenzaldehyde and 4-(N,N-dimethylamino)benzaldehyde to form new chalcone derivatives A4-A9. Ring closure of these compounds A4-A9 with urea and malononitrile afforded new oxopyrimidine derivatives A10-A15 and cyanopyridine derivatives A16-A21, respectively. These compounds were characterized by FT-IR, 1H NMR, and 13C NMR spectroscopy. The second part of this work included some of the i
... Show MoreThe mineralogical investigation, geochemical analysis, and grain size calculation were carried out for floodplain sediment in the Tigris River to identify the properties of the sediment. The average values of the three main sediment classes, very fine sand, silt, and clay are 9.67, 62.53 and 27.80%, respectively. The silt size fraction was predominant. The classification and nomenclature of surface sediment types from the floodplain of the Tigris River are sandy-silt and mud, and they are the dominant sediment. Statistical parameters of grain size analysis refer to the average of the median values 3.74 Φ very fine sand; mean in average 6.16 Φ coarse silt; standard deviation evident by average 1.30 Φ poorly sorted, skewed; in
... Show MoreThe present study deals with the websites of Iraqi political parties on the internet to identify the effectiveness in providing communicative applications that help audience to participate, express their opinions, their positions, and other aspects reflecting the extent of employing modern technological tools to allow opportunities for political, and democratic participation since the internet has become an effective tool for political communications of political parties. The research sample includes eight political parties. The research concludes that the Iraqi political parties do not employ interactive communication patterns to reflect their interests in communicating with the public, providing opportunities for their participation an
... Show MoreThe possibility of predicting the mass transfer controlled CaCO3 scale removal rate has been investigated.
Experiments were carried out using chelating agents as a cleaning solution at different time and Reynolds’s number. The results of CaCO3 scale removal or (mass transfer rate) (as it is the controlling process) are compared with proposed model of prandtl’s and Taylor particularly based on the concept of analogy among momentum and mass transfer.
Correlation for the variation of Sherwood number ( or mass transfer rate ) with Reynolds’s number have been obtained .
Abstract
This research aims to improve the provided health service level inside Baghdad hospitals and the Yarmouk educational, as well as to shed light on the reality of the health service and the quality within the major operations room in both hospitals, as the operations room represent the research community, as was the use of some quality tools Pareto and Ishikawa diagram to measure and assess the level of quality provided, and include research problem to find out what are the problems and obstacles facing the process of improving quality in both hospitals, and whether there are scientifically accurate method to assess the quality of health service in Baghdad's Yarmouk hospital and educational . Where the researcher h
... Show MoreThe research seeks to highlight the importance of digital finance in banking by providing financial and banking services and its role in improving the access of financial services to customers at the farthest possible point by using modern technology to finance their needs by granting them cash credits through electronic payment tools to facilitate them and shorten time and effort as well as Low cost, and this cannot be achieved without concerted efforts and the provision of basic infrastructure that includes connecting the Internet to all targeted areas, whether cities or rural areas, as well as distributing the largest possible number of ATMs and sending specialized teams to those areas that develop in customers the culture of digital
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