In this paper, the deterministic and the stochastic models are proposed to study the interaction of the Coronavirus (COVID-19) with host cells inside the human body. In the deterministic model, the value of the basic reproduction number   determines the persistence or extinction of the COVID-19. If   , one infected cell will transmit the virus to less than one cell, as a result,  the person carrying the Coronavirus will get rid of the disease .If   the infected cell  will be able to infect  all  cells that contain ACE receptors. The stochastic model proves that if  are sufficiently large then maybe  give  us ultimate disease extinction although ,  and this  facts also proved by computer simulation.

Aim: The Aim of the study is to compare between Er,Cr:YSGG 2780 nm laser and carbide fissure bur in root-end resection regarding the morphological variations, temperature changes and the duration of resection process.

Settings and Design: 5 W, 25 Hz, 50% water, 80% air,25.47 J/cm2 .

Material and method: twenty-one extracted single rooted teeth endodontically were treated, twenty teeth were obturated and divided into two groups according to method of resection. Group 1 root-end resected using cross cut carbide bur while group 2 root-end resected using laser with MGG6 sapphire tip of 600 μm diameter. Temperature on external root surface and duration of resection were recor

The human kidney is one of the most important organs in the human body; it performs many functions
and has a great impact on the work of the rest of the organs. Among the most important possible treatments is
dialysis, which works as an external artificial kidney, and several studies have worked to enhance the
mechanism of dialysate flow and improve the permeability of its membrane. This study introduces a new
numerical model based on previous research discussing the variations in the concentrations of sodium,
potassium, and urea in the extracellular area in the blood during hemodialysis. We simulated the differential
equations related to mass transfer diffusion and we developed the model in MATLAB Simu

Environmental education is considered as process of getting Humans in communication with this environment and all its various resources. such process requires acquiring knowledge about the environment that com help humans understand their correlative relations with the environmental elements on one hand and among the environmental elements themselves on the other . Besides, such a process requires developing human skills that help them participate in developing environmental circumstances. Therefore environmental education is responsible for perspective and cultural development that governs human behavior. Regarding their environment and stimulating tendencies and interests towards the environment , let alone helping humans acquire the c

Strategic decision making is considered one of the important processes for senior management in contemporary business organizations and service organizations due to the properties of the service such as intangibility, concomitance and mortality. Decision-making has three approaches according to the opinions of most of the writers and researchers in the administrative area: an analytical approach, intuitive approach and behavioral approach. This research is trying to discover the nature of the relationship in terms of the link between the impact of each of these approaches and efficiency of marketing services by selecting an intentional sample of 58 researches from the Directorate General of Traffic, one of the Iraqi Interior Ministry ins

    This research on women under the title (Empowerment of women…  From value education to the creation of human morality), includes a disclosure of the reasons that prevented women from performing their human role in the development of human societies and treatments that can provide to solve this big problem in the life These communities, especially the Eastern societies and the religious ones, believe that the woman has not received the care and care to raise her human values ​​in order to contribute to the required social contribution, for historical, economic, moral, religious, social and cultural reasons. And by shedding light on specific definitions of the most important rules on which the research relied

اصبحت وسائل الاعلام في ظل المتغيرات الجديدة قادرة على صياغة وعي وثقافة وهوية الشعوب الى حد كبير في المجتمعات المعاصرة , وذلك نظرا لما تتمتع به من اليات مختصة في التأثير والمتمثلة عموما في التكرار المتنوع للرسالة الاعلامية وقدرة الخطاب الاعلامي في معالجة القضايا المختلفة فضلا عن تقديم المعلومات وغزارتها وشرحها المستفيض , وقد بات من الواضح جدا مدى التأثيرات الكبيرة التي من الممكن ان يحدثها تعرض الافراد للمواق

Allah Almighty has aggrandized the position of orphans and elevated their status in the society and has given the graces for those who sponsor the orphan and care for and protecting them, even those who rub their heads. The divine care is manifested in the verses of the Holy Bible and the Holy Quran. Therefore, the whole world cared for the orphan, and called for the rights of the orphans in the conferences and the channels. But all that was little effort that does not meet what the orphan need and some were only ink on paper that were not applied. All that mentioned above is necessary in dealing with the study (the rights of orphans in the Old Testament and Islam, a Comparative Study). The study was divided into a Preface and four inquirie

Praise be to Allah, the Lord of the Worlds, the best prayer and the best prayer, on our master Muhammad, and on his pure God, and his companions and the faithful, and who followed them by charity to the day of religion. This relationship between emphasis, is a sincere, and this harmony, such as the relationship between water, and the green, but it is good, but, with greenery, it is better, and as well as alone, is a beautiful view, but the most beautiful, with the most beautiful. From here he was starting on myself in writing the fundamentalist research of jurisprudence, to show the depth of this interconnection. The doctrine as a new term, then the taj al-Din al-Suobki came after three centuries, and a

This research investigates the meanings and significance of the verse and the concluded educational purports. The expression “And in the heaven is your provision” signifies the deism of Allah. This research introduces the what have been said by Quran Explainers about meaning of Heaven & Provision. It introduces also the meaning of the sentence “which you are promised” and its concluded educational purports. This research discuses the role of educational institutions as well as the family and mosques in connecting Muslims and their children with the promise given by Allah.

Provision is guaranteed for all people if moral and material causes have been considered.

Key Words:

Purports – Educational – Co