Over the course of two centuries, Portugal emerged as one of the most powerful European empires, with colonies stretching from Asia and Africa to Brazil. A significant factor in this expansion was the role of winds, which carried one of Cabral’s ships westward, landing unexpectedly on unknown shores—the Brazilian coasts. These territories later became some of Portugal’s richest and most important colonies. Therefore, the study begins in the 16th century and concludes at the end of the 17th century. The study was divided into four sections. The first section addressed Portugal's discovery 0022 of Brazil and its naming before it gained economic importance. The second section discussed the Portuguese occupation of Brazil in 1530 and its

This article suggests and explores a three-species food chain model that includes fear effects, refuges depending on predators, and cannibalism at the second level. The Holling type II functional response determines food consumption between stages of the food chain. This study examined the long-term behavior and impacts of the suggested model's essential elements. The model's solution properties were studied. The existence and stability of every probable equilibrium point were examined. The persistence needs of the system have been determined. It was discovered what conditions could lead to local bifurcation at equilibrium points. Appropriate Lyapunov functions are utilized to investigate the overall dynamics of the system. To support the a

Vascular patterns were seen to be a probable identification characteristic of the biometric system. Since then, many studies have investigated and proposed different techniques which exploited this feature and used it for the identification and verification purposes. The conventional biometric features like the iris, fingerprints and face recognition have been thoroughly investigated, however, during the past few years, finger vein patterns have been recognized as a reliable biometric feature. This study discusses the application of the vein biometric system. Though the vein pattern can be a very appealing topic of research, there are many challenges in this field and some improvements need to be carried out. Here, the researchers reviewed

Due to the fact that living organisms do not exist individually, but rather exist in clusters interacting with each other, which helps to spread epidemics among them. Therefore, the study of the prey-predator system in the presence of an infectious disease is an important topic because the disease affects the system's dynamics and its existence. The presence of the hunting cooperation characteristic and the induced fear in the prey community impairs the growth rate of the prey and therefore affects the presence of the predator as well. Therefore, this research is interested in studying an eco-epidemiological system that includes the above factors. Therefore, an eco-epidemiological prey-predator model incorporating predation fear and

One of the most difficult issues in the history of communication technology is the transmission of secure images. On the internet, photos are used and shared by millions of individuals for both private and business reasons. Utilizing encryption methods to change the original image into an unintelligible or scrambled version is one way to achieve safe image transfer over the network. Cryptographic approaches based on chaotic logistic theory provide several new and promising options for developing secure Image encryption methods. The main aim of this paper is to build a secure system for encrypting gray and color images. The proposed system consists of two stages, the first stage is the encryption process, in which the keys are genera

Receipt date: 8/8/2020 acceptance date: 9/11/2020 Publication date: 31/12/2021

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           The American-Iranian relations have been characterized by tensions since the arrival of the guardian jurist regime in Iran to leadership in 1979, as it was considered a turning point not only in the cont

Humans knew writing and to blog motivated by the need for registration and documentation, and tried from the very beginning of research to find the most suitable material for this purpose, he used many different materials in form, nature, and composition, so it is written on the mud by the ancient Sumerian people in different forms and when the text is long Numbered as the pages of the book at the present time, this research will deal with the damage to manuscripts and then find ways to address them.

The research aimed at studying the inhibitive effect of the hot watery dry and ethanolic ginger(85%) and fragrant oil which are added in concentrates of o.o25, o.o5o and 0.1g / 100g respectively in the growth of bacteria and molds. The results of the initial chemical diagnosis showed containment of ginger roots extract on. Alkaloids, Glycosides, Flavonoids and Suponins. The highest inhibitive effect of the bacteria reached the concentrate . 0.1% of the oil extract then the concentrate 0.050% of the ethanolic hot extract follows it. While 0.1% was the least inhibitive concentrate for the hot watery extract. But the inhibitive effect of the hot oily and alcoholic extracts in the numbers of molds colonies was 0.025%, when the concentrate 0.1%