Fragile words have been already considered in the context of automata groups. Here we focus our attention on a special class of strongly fragile words that we call Catalan fragile words. Among other properties, we show that there exists a one-to-one correspondence between the set of Catalan fragile words and the set of full binary trees.

During this present decade, the concept of "fragile states" has become very important in the international politics. Also, human security has entered the literature of this field from the last decade of the twentieth century. This assay tries to investigate the fragile states' effect on human security. So, it has discussed fragile states, factors determining fragility, and the formation of this kind of states. Fragile states intensify human security crisis because of their inability in providing public services and performing their prevalent governmental role in security and development fields. In addition, this piece of writing investigates the necessity of a change in present approaches to the security and emphasis the role of national state, paying attention to the protect responsibility, and the role of international society in dealing with the fragile states problem.

It is difficult to live in a residential complex without cooperation and organizing collective action. Ignoring the importance of cooperation deactivates the effects of small and scattered investments of the residents, wastes small endeavors and collective assets and brings about an unsecure environment for individuals. As a result, it has been attempted to investigate residents’ perceptions of cooperation and its components through Grounded theory and interviewing residential complexes’ residents in Mashad city. Thus, Laleh residential compex was studied in the present research from different aspects and angels. Therefore, 35 semi- structured interviews were carried out. On the basis of the analysis of findings within the research paradigm, it was found that fragile cooperation constituted the core. Constraining structure was presented as the underlying conditions. The structures people may be able to influence but they have no control over them. Individual charactersitics such cooperation evasion, interactional gap, negativitism, and weak central control are among the causal conditions that lead to “fragile cooperation”. The consequences of such interactions is that even if clear norms and rules prevail in the complex and that there is a descipline in the complex, these conditions are very unstable. And in case there are few number of free riders, the mentioned common good can be easily lost.

We address the problem of finding examples of non-bireversible transducers defining free groups, we show examples of transducers with sink accessible from every state which generate free groups, and, in general, we link this problem to the non-existence of certain words with interesting combinatorial and geometrical properties that we call fragile words. By using this notion, we exhibit a series of transducers constructed from Cayley graphs of finite groups whose defined semi groups are free, and thus having exponential growth.

Following the cold war and the terrorist attacks of Sept.11, 2001, the term "fragile states" has gained increasing prominence in security debates and the international community turned his attention to the hows of engagement in such countries. These security concerns originate from several factors: emphasis on establishing peace and security and this growing recognition that development and security are interrelated and the stability of state plays an influential role in its development. The term "fragile state" refers to the weak states which are vulnerable to internal and external threats and have a poor government incapable of managing domestic affairs and foreign policy and even it self can be regarded as a threat to the security of state. The current study aims to investigate the effects of Iraq's fragile state on the security threats to the women of this country using indexes of "state fragility" and "human security". Many thinkers believe that the crisis and civil war in Iraq after 2003 are caused by failure in nation- state building process and weakness of Iraqi government in the maintenance of societal order and unity. The fragility of state in Iraq, during these years has crucially affected the human security specially security of women. This thesis seeks to clarify the role of fragile state of Iraq in exacerbating the crisis giving rise to serious threats to the security of women".

Todays, cities have become one of the most complicated systems, which may become fragile when not managed appropriately. In order to prevent fragility, cities should respond more quickly and effectively to complicated threats, which requires an accurate understanding of the concept of fragility. In this regard, a systematic review was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to understand the concept of urban fragility by electronic search using keywords combined with Boolean OR and AND operators in Google Scholar, ISI Web of Science, and Scopus. Based on the reviewed articles, the dimensions of urban fragility, including the economic, social, governmental, environmental, international relations, and economic, social, and political conditions of individuals, were identified for each component and indicator. Given the definition of fragility and its dimensions, the present study can provide an opportunity for identifying the causes of fragility in cities and providing some solutions.

This article aims to understand the nature and causes of reproducing bureaucratic corruption in transitional societies from the legal sociology view point. According to the authors, since the operation of bureaucratic system firstly is determined by the nature of power elites and the present structural relationships in the society; on this basis, the protector-nurturing mentality and surveillance lacking of dominant elites alongside lacking rule of law is the pivotal factor of growing corruption in transitional societies. This dilemma gradually leads to forming an anomic situation in various structures of bureaucracy and changing it into an arena for rent-based games and thus, causes the process of development to wane and accordingly, causes the society to involve mentally and morally in contradiction and turmoil and from the perspective of political economy subject to increasing passivity and devolution. The final resultant of this situation is social capital crisis and vulnerability in human capital. The article with an expressive approach and in the mold of combination of various sociological theories shows why and how bureaucratic corruption in transitional societies continues reproduction, and finally deals with the foundations of an anticorruption policy and its implications.