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The rivalry between China and the United States in the new century is one of the most important drivers of geopolitical rivalries at various regional and trans regional levels. China is considered one of the great powers that has the potential to become a superpower and challenge the current position of the United States, something that has worried US strategists and officials. As a result, in the second decade of the 21st century, the United States shifted the focus of its national security strategy from the Middle East to East Asia in order to counter this potential threat. With the withdrawal or diminishing presence of the US presence in the region, traditional US allies such as Israel and Arab countries are afraid of expanding the sphere of influence of their geopolitical rivals, namely Iran and Turkey, and given the historical experiences of the region and Iran's geopolitical influence in the current situation, these countries have been forced to cooperate bilaterally and multilaterally. Israel has traditionally chosen the Peripheral Alliance strategy as a complement to its national security strategy. Given the possibility of a reduction in military forces in the Middle East, the Arab-Israeli agreement in the form of the Abraham Accords Peace Agreement seems to represent a new Rimland with the aim of controlling and limiting the geopolitical influence of the Islamic Republic of Iran. Using the descriptive-analytical method and based on library and Internet resources, tries to provide a geopolitical explanation of the Abrahamic Accords in terms of its effects and consequences on regional relations in the Persian Gulf and especially the goals and interests of the Islamic Republic of Iran. The results show that if the project is implemented, we can expect the emergence of a new regional Rimland with the aim of controlling and weakening Iran.

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Aims: Monitoring of the fish biomass is one of the basic principal of fisheries management, but ornamental and reef fish stocks, because of difficulty of estimating their abundance, have been less studied than others. The aim of this study was to estimate the standing biomass of ornamental and reef fishes in Larak Island, in the Strait of Hormuz.
Materials &Methods: Standing biomass of the fish species was assessed seasonally using Underwater Visual Census Method (UVCm) in coral reefs and  mesophotic coral reefs in Larak Island throughout 2018 and 2019. Two popular methods in UVCm (belt transect and stationary point) were used based on topography of sea bottom. The confidence interval of estimated standing biomass is calculated using bootstrapping method.
Findings: The standing biomass of ornamental and reef fishes is estimated as 2522.18, 5222.17 and 1325.15(Kg.) in Site 1, Site 2 and Site 3, that are located in 3-15meters depth. The standing biomass at Site 4, was estimated as 884.13kg. The minimum were observed in summer, also the result showed  that the standing biomass in summer was significantly lower than other seasons (P <0.05). In addition, the temporal diagnostic test showed that population structure of fish in the spring, autumn, and winter seasons was similar but significantly different from the population structure in summer.
Conclusion: The less of standing biomass in summer season can be affected  by seasonal migrations of fish in tropical and subtropical waters to deeper waters, in order to trade of the stresses caused by temperature fluctuations.
 

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The aim of this study was to identify different population broodstocks of Litopenaeus vannamei and effect of inbreeding and cross-inbreeding on genetic characteristics and inbreeding coefficient of offspring in the next generation. According to origin of broodstocks kept in hatcheries of Bushehr province in the first generation, different populations were identified through microsatellite method from Hybrid, High health and Molokai stocks then, in the next generations genetic characteristics of offspring from their inbreeding and cross-inbreeding were examined. The results showed that the amount of genetic diversity in Molokai and High Health stocks (0.46±0.09 and 0.50±0.07) was more than hybrid stock (0.38±0.06). The inbreeding coefficients of Molokai, High Health and hybrid stocks were 0.14, 0.31 and 0.41, respectively. Due to the low genetic distance between the hybrid and Molokai stocks, after mixing them together Molokai and High Health populations were introduced as the first generation broodstock. In the second generation, despite the high genetic diversity in the offspring of Molokai×High Health (0.47±0.12) and High Health×Molokai (0.39±0.08) than the offspring of Molokai×Molokai (0.19±0.04) and High Health× High Health (0.11±0.03), these values were reduced compared to the first generation. The lowest and highest inbreeding coefficients were related to the offspring of Molokai×High Health (0.268 ±0.18) and Molokai× Molokai (0.853±0.145), respectively. According to the results, it can be said that the lack of knowledge about the genetic characteristics of broodstocks and mating between individual relationships (full and half sib) can reduce genetic characteristics and genetic depression due to increased inbreeding coefficients in next generations.