zahra agha mohammadi

 The latest generation of bonding agents is increasingly embraced and well-suited to fulfilling the requirements for durable restorations. This study aimed to assess microleakage levels of three self-etch adhesives (Clearfil SE (SE), Protect (PB), and Tri-S (TS) Bonds) in composite restorations at both occlusal and cervical borders, while considering the impact of water storage over different time intervals.

 Standard Class V cavities were prepared on buccal surfaces of 84 human premolars at the level of cementoenamel junction. The samples were randomly assigned to six groups (N=14). The corresponding bonding procedure in each group was completed, and the cavities were filled using Clearfil AP-X (Kuraray). Following thermocycling, the teeth were stored in deionized water within an incubator for 24-hour and 6-month intervals. Statistical analysis of microleakage data was conducted utilizing Kruskal-Wallis and Mann-Whitney U tests at p<0.05.

 Following a 24-hour interval, the level of microleakage at the occlusal surface was greater than the gingival surface for SE. No statistically significant differences were observed in microleakage at the occlusal and cervical borders after 24h of water storage for the PB and TS groups (P=0.51, 0.16). None of the SE and TS group samples showed leakage at the occlusal or cervical margins following a 6-month interval.

 Self-etching bonding agents indicated increased occlusal microleakage compared to the cervical margin microleakage.

Islamic State of Iraq and Syria (ISIS) has been one of the most important global events, especially in the Middle East strategic region since 2011. By now, ISIS political dimensions are studied by many political researchers and sociologists. But there is a lack of deep studies about this terrorist group barbaric acts through the political psychology of grouping. Therefore, in this study, the authors attempt to answer this question that how ISIS violence can be analyzed in political psychological perspective based on group theories. The answer to this question is based on this assumption that although ISIS barbarism and violence may have different psychological factors, one of the main reasons is the psychology of group. There are intergroup pressures in this terrorist groups which result to weaken members mind ability as well as bring about incorrect understanding about reality, nonchalantly ethical judging and severe tendency towards violence. Although ISIS is panting the last days of his life in Iraq and Syria by Mosul reoccupation by Iraqi army (2017) and narrowing of ISIS siege ring in Syria. However, ISIS attitude is alive as before in the Middle East. This research is based on descriptive- analysis method by using internet and library resources.

A decade after the establishment of the Saudi regime Riyadh and Washingtonconstructed a strategic alliance between themselves in 1945. On the other hand,given the “Pivot to Asia” doctrine adopted by the Obama and TrumpAdministrations, the decline of Washington's dependence on Saudi oil, as wellas some important events such as the murdering of Saudi journalist JamalKhashoggi by Riyadh officials, the prospect of relations between the twocountries has been highlighted in political circles. Based on a scenarioplanningstudy, the current paper tries to answer the question: “what willhappen to the future of US-Saudi relations considering the aftermath of theKhashoggi murder?” Concerning the impact of this fiasco on the future of USSaudirelations, we can logically consider five scenarios: the continuation of thestatus quo, the deepening of strategic relations, the decline of strategic relations,a strategic shift, and, finally, the elimination of strategic relations. But givenongoing circumstances, the deepening or end of strategic relations is unlikely tohappen, the present article only focuses on the three other scenarios; thecontinuation of the status quo, the power shift and the decline of strategicrelations amidst the two countries. However, the removal of Mohammed binSalman (MBS) from the position of crown prince (should it be low-cost) couldalso be in Washington's agenda for maintaining strategic ties between the twocountries. The paper's hypothesis is inclined to the status quo scenario and arguesthat with the official stances of the Trump Administration, in particular that ofNovember 20, 2018, the strategic alliance of Riyadh-Washington will continue,with more expenses shouldered from the Riyadh side.

One year after the establishment of the Saudi regime in 1933, Riyadh and Washington have constructed a strategic alliance between themselves. This unique relationship has continued so far with some fluctuations (2018). Meanwhile, there have been some signals in the US foreign policy in the Obama and Trump eras which indicates some changes in the US Middle East policy. The trends such as lowering Washington's dependence on Saudi oil and the American political shift from the Middle East to East Asia indicate that the future of Washington's relations with Saudi Arabia may change dramatically. The question posed in this article is how we can assess the future of Saudi Arabia and the United States alliance in the Trump era (assuming Trump`s election for the second term) and what the probable scenarios are for Saudi Arabia to play in the Middle East in the future. The hypothesis is that US foreign policy under the Trump administration has less human rights and democratic concerns and so long as Saudi Arabia is acting in favor of US grand strategy in the Middle East, their alliance will not change. Therefore, the strategic alliance of Riyadh-Washington will continue with more assuming security costs by Riyadh. Furthermore, in the most optimistic way, Saudi Arabia will play the role of the regional king following the great king (US) as well as the swing state strategy. This is a descriptive-analytic research based on Randall Schuler's theory of "balance of interests."

In the post-bipolar period, the nature of international conflicts has changed and peacekeeping missions increased in Critical parts of the world such as Africa. Sudan crisis can be nominated as the greatest humanitarian catastrophe in the world that has provoked the reaction of countries and the United Nations. The UN Security Council through prescription of multiple resolutions play vital role as the main operator of keeping the international peace and security. Current article evaluates peacekeeping missions in Africa and seeks to answer why the Security Council’s peacekeeping missions have not been successful in South Sudan, Darfur and Abyei? Failure to follow the effective components in peacekeeping operations caused to fizzle the UN in these missions. The mentioned elements include consent and goodwill of the two parties, impartiality, collaboration and participation of key foreign players, sense of security for the parties involved, transparency in the functions and powers of the mission, timely and rapid deployment of peacekeeping operations, domestic and international coordination and cooperation, competent leadership of the peacekeeping mission, and considering the causes and reasons of war.

Islamic fundamentalism and terrorism is one of the most important threats to peace and security in the Middle East. ISIS considered as one of the most dangerous phenomenon of terrorism in the region. This group has seized some parts of Iraq, Syria and Libya . Current study intends to answer the following question; what is the main reason of the continuation and reproduction of terrorist groups like ISIS in Middle East? Although, the countries of region involved in fighting against terrorist groups for a long time, but they have not achieved success in this arena yet. So according to game theory and deadlock dilemma following hypothesis has been proposed. Conflicting interests of beneficiary actors caused they take the strategy of Non-cooperation. Hence this issue has developed appropriate ground to form and continuity of terrorist groups like ISIS in Syria and Iraq. This research based on Descriptive and Analytical Method .

After World War II, Japan came under the security umbrella of the United States. Due to dominating military logic over the cold war, Japan played a small role in this era and was inactive in the case of international affairs. However, the collapse of bipolar system paved the way for Japan to implement more independent foreign policy. At this time, Central Asia was involved in post-cold war evolutions so that five independent republics were established in the region. The coincidence of these two evolutions raises the question in mind that what have been the aspects and plans of Japan’s foreign policy in Central Asia. Japan’s regional policy in Central Asia has features rooted in Yoshida’s Doctrine. During the cold war era, Japan was a strategic and inactive country, but in the post-cold war era, it transformed into a flexible government in terms of the international arena. The interpretation of this flexibility in Central Asia can be justified by less activity in political and military plans and greater emphasis on economic aspects. In general, Japan’s foreign policy in Central Asia has both political and economic aspects, but within Japan’s plan, the economic aspect has got the higher priority. The essence of Japan’s plans in Central Asia sends out a message to its neighbor that Tokyo does not intend to compete for geopolitics in the region and attempts to act based on the common economic interests.
In this paper, Japan’s regional policy has been investigated based on hegemonic theory.

Since 2001 Ashgabat lunched more normal pattern of neutrality. In 2006, with the arrival of Gurbanguly Berdimuhamedow as new leader, The process of change in foreign policy intensified. In view of the aforementioned considerations, this paper seeks to answer the two main questions: what kind of changes Turkmenistan's neutrality strategy have experienced? And what have been the economic consequences of this strategy? The hypothesis here is that the Turkmenistan’s foreign policy until 2006 was based on Isolation. After 2001 negative neutrality has been adopted. Then, with the arrival of Gurbanguly Berdimuhamedow, active and positive neutrality has been adopted. This strategy explain as one of the main factors of economic growth in Turkmenistan in the last ten years (2016-2006).