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Environmental differences and similarities are the driving factor of travel and tourism; The Africa will be one of the main destinations for tourists in the future, with a great variety of tourist attractions, especially natural and historical. Available statistics show this fact well. All this can be a good opportunity to develop relations between Iran and African countries; Therefore, it is necessary to identify and introduce them to formulate strategic plans. Tourism is a suitable field for the development of cooperation, and paying attention to tourism and including it in diplomatic programs and relations will help to expand relations and remove obstacles; Therefore, in diplomatic relations, serious planning for a more detailed understanding of Africa, including its tourism market, should be put on the agenda. The main purpose of this article is to introduce Africa's environmental capabilities in the field of tourism with reference to the continent's plans in this regard and to answer the question of how tourism can be an effective element in the development of relations between countries. The research method is documentary and library studies and referring to statistics and figures related to tourism to provide solutions for the development of bilateral and multilateral cooperation. The general result of the present research shows the absence of a written program from the I.R. Iran for the development of tourism with Africa. A special suggestion in this regard is to prioritize tourism as a phenomenon with socio-cultural, economic and even political dimensions in the macro plans.

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Considering changes in economic conditions and global priorities in the last decade, development objectives such as poverty reduction and income distribution were typically cast in terms of economic growth. Therefore, poverty reduction through rural development was at the center of government development plan. The objective of this study is to analyze the impact of government spending on the rural economic development. The development indicators included in the model comprise agricultural production, non-farm employment and poverty reduction. To this end, the elasticity of the above indicators is estimated with respect to rural infrastructures such as education, transportation, telecommunication and electricity capacity and then linkage between rural infrastructures and government spending are identified. A system of simultaneous equations approach is used to model and estimate the equations using the data over the period 1981-2005. Results of estimate indicate that government spending have positive and significant impact on the poverty reduction and non-farm employment.

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The purpose of this study is to introduce an index for calculating transaction costs in Iran over the 1984-2006 period. In order to calculate the transaction costs, Fuzzy Logic Approach is employed using MATLAB software. Based on the literature review, the determinants of the transaction costs are identified. They mainly comprise the standard deviation of the inflation rate, economic freedom, cash ratio and the ratio of public costs to GDP. Three scenarios are considered to calculate the transaction costs. Overall, the result shows that there is a cyclical trend in the transaction costs over the period considered in this study. The transaction costs decreased after the period of war - 1372-1374 - in all three scenarios considered. Following this period, however, the transaction costs has an upward trend and continued to increase until 1381 in all scenarios. After this increasing trend, the transaction costs have again decreased in the three scenarios.

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Over the past decades, one of the most important indicators of the development and welfare was economic growth or any quantitative variables such as gross domestic product and income per capita. As long as the World has experienced a wide gap among rich and poor countries, economic growth as the only effective factor in welfare was questioned and consequently, gross domestic product distribution and other issues related to social justice raised as a distinguished feature of welfare and development economics. Estimating welfare trend in Iran can mirror the policies imposed by policymakers. Therefore, this paper aims to estimate welfare index during 1974- 2006 period. In this paper MATLAB software is used to estimate welfare employing fuzzy logic model using Sen's approach. The results of this study show that in spite of high degrees of vacillation, welfare trend was ascending during the aforementioned years. The maximum value obtained was 0.715 in 2005 while the minimum value obtained was 0.421 in 1994.

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Aims: Studying design regulations to eliminate contradictions and deficiencies is a dynamic and important research topic in most parts of the world. There is no doubt about the necessity of regulations, but the question is how to design regulations that does not lead to decrease in quality and tension in design process. The aim of research is to find roots of the reducing function of national regulations, focusing on the fourth issue, in fading design concepts in construction sector.

Methods: The research is conducted analytically, based on content analysis and logical reasoning of library resources, and the research framework is determined through interviews with selected experts.

Findings: National regulations are prescriptive, that determining solutions, inflexibility, and standardization is their most significant characteristics. Reducing design issues, substituting skills with knowledge, relieving design responsibility through reliance on standards, setting minimums as objectives, and eliminating incentives for creativity and innovation are the main reasons for the diming function of national regulations in the design and construction sector.

Conclusion: The structure and content of regulations make changes in designers' methods and work. The prescriptive approach, with its particular characteristics, is not suitable for formulating architectural design regulations and requires regulations that do not compel designers to think in specific paths. The centralization of standards has limited design issues and, by reducing the level of design to that of technicians, has obscured the roles of innovative designers and design concepts, creating a platform for non-specialists to enter the design and construction domain.

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The purpose of this study is to investigate the ability of smart scaffolds of Kappa-carrageenan (Carr) and the combination of Kappa-carrageenan and quince seed mucilage (Carr:Quc) to support C2C12 viability and growth for cultured meat production. Carr and Carr:Quc with a final concentration of 1.5% (v/w) were developed using a 5% potassium chloride solution. The capability of the scaffolds to respond to the pH change of the environment was evaluated, and the viability of C2C12 at normal pH (7.4) and varying pH levels (7.4-5.5) was assessed. The evaluation of swelling changes with varying pH (pH 1-7) showed that for the Carr scaffold, the highest swelling was observed at pH 5, reaching 145%, which showed a significant difference compared to swelling at other pH levels (p < 0.05). The highest swelling for the Carr:Quc scaffold was also observed at pH 5, reaching 428%, with a significant difference compared to swelling at other pH levels (p < 0.05). Moreover, the change in the swelling behavior of the scaffolds was evaluated by changing the pH from 7.4 to 5.5. Carr did not show any swelling change, while Carr:Quc demonstrated a significant change in swelling after exposure to pH 5.5 for 30, 45, 60, 180, and 360 min. On Carr:Quc, C2C12 showed higher viability in normal conditions compared to varying pH levels from 7.4 to 5.5. Furthermore, after culturing on Carr:Quc, C2C12 maintained their viability throughout the culture period for 15 days at pH 7.4 and showed the potential for spheroid formation. The findings of this study could pave the way for the design of scaffolds made of edible biopolymers to facilitate tissue engineering of cultured meat