درخت حوزه‌های تخصصی

In this paper we utilize the main findings from the recent literature to set the economic foundation for the existence of money, its modern interpretation as “memory” (Chokerlakota 1998) and how the Blockchain technology has empowered crypto currencies to perform this role in the information age. To locate the issue in a historical perspective and in line with this strand of thought, we consider direct and indirect exchange and the Wicksell triangle and discuss the frictions under which the need for fiat money arises. More specifically, it will be argued when “reputation” (trust) is imperfect, high cost of enforcing contracts undermines the case for pure private money (credit). The corner stones of the present system, a remnant of 20th century central banks’ fiat money and “private money” issued by the banking system and the current payment system relies primarily on the technologies and centralized “trust” protocols developed before the early 1990s. The internet and the digital technology have greatly reduced the costs of gathering and storing information and thus is able to compete with the traditional payment system in the future in the niche markets. In this connection, how the Blockchain technology can complement internet technology for creation of crypto currency for payments, money transfers and asset purchases will be discussed. Finally, the paper examines whether crypto currencies can replace money in its current form. It will be shown that in the case of crypto currencies, high price volatility undermines the store of value function of money and this factor plus issues pertaining to money laundering and taxation prevents them to become a widespread form of money, though they will be used as a medium of exchange in the niche markets.

The present study aims to identify the effectiveness of cognitive rehabilitation on different types of attention in the third-grade students with specific learning disabilities (reading) considering moderating role of gender. As a quasi-experimental research, the study uses pretest-posttest design with control group. Façade testing, a helpful tool to identify the reading difficulties and dyslexia in elementary school, is performed to determine the research sample among the third-grade students in Tabriz. The students who score above average survey response rate are identified as specific learning-disability learners (reading). Among these students, 60 (four groups of 15) are selected by simple random sampling method and randomly divided into two experimental groups (two groups of 15, one group female students and the other male students who received cognitive rehabilitation training program) and two control groups. Cognitive rehabilitation training is delivered through Smart Sound training software (8-level computer-based cognitive rehabilitation in reading disorder). Attention is also measured by focused/sustained attention and scattered attention test designed in Sina Institute. To analyze the data, multivariate analysis of covariance is used. The results indicate cognitive rehabilitation is effective in focused/sustained attention, scattered attention, and reaction time in specific learning-disability students and gender does not have a moderating effect. Accordingly, cognitive rehabilitation does not have meaningful effect in the increase of focused attention, scattered attention and reaction time in male and female students.