Purpose: Managers are one of the important elements of an organization, for this reason, in order to draw the future of the organization, it is necessary for the planners to specify the conditions of their selection and appointment. Therefore, the current research has been done with the aim of identifying and analyzing the components of selecting future principals.Method: In this research, comparative and benchmarking method is used as a prospective approach. This approach is based on the belief that today's advanced organizations/countries can be considered as a model for the future of another organization/countries in their respective subjects. For this, first, the fields of comparison and benchmarking were determined using Brody's four-step comparison method; then the countries of Canada, Finland, Australia, South Africa, and Japan were selected according to the qualitative balance value in the international advanced TEAMS test, human development index, life quality index(health, instruction, and welfare), education quality index, and other scientific-scholarly indexes; finally, by extracting the criteria for the selection and appointment of principals through content analysis and comparison with Iran, the proposed framework for Iran has been presented.Findings: A total of 61 components for the selection of secondary school principals were identified from among the studies conducted in the selected countries in this article. By extracting the commonalities and differences of each of the components among the countries, it was found that the highest index of manager selection and appointment belongs to Japan and the lowest one is related to Finland.Conclusion: There are similarities between the components of selection of principals of secondary schools in Iran and selected countries. In Iran, special attention should be paid to important components such as adherence to religious principles, appropriate personality traits, creativity and innovation, motivation to develop capabilities, professional growth, power of supervision and accountability, social image, leader skills, and purposefulness and foresight.

Automatic topic detection seems unavoidable in social media analysis due to big text data which their users generate. Clustering-based methods are one of the most important and up-to-date categories in topic detection. The goal of this research is to have a wide study on this category. Therefore, this paper aims to study the main components of clustering-based-topic-detection, which are embedding methods, distance metrics, and clustering algorithms. Transfer learning and consequently pretrained language models and word embeddings have been considered in recent years. Regarding the importance of embedding methods, the efficiency of five new embedding methods, from earlier to recent ones, are compared in this paper. To conduct our study, two commonly used distance metrics, in addition to five important clustering algorithms in the field of topic detection, are implemented by the authors. As COVID-19 has turned into a hot trending topic on social networks in recent years, a dataset including one-month tweets collected with COVID-19-related hashtags is used for this study. More than 7500 experiments are performed to determine tunable parameters. Then all combinations of embedding methods, distance metrics and clustering algorithms (50 combinations) are evaluated using Silhouette metric. Results show that T5 strongly outperforms other embedding methods, cosine distance is weakly better than other distance metrics, and DBSCAN is superior to other clustering algorithms.

1The aim of present research in the first stage was to extract astaxanthin from Haematococcus pluvialis using acid-acetone method and then nanoencapsulation of the pigment using maltodextrin-sodium caseinate coating. In the next step, antioxidant and antibacterial activities of nanocapsules carrying astaxanthin and the free form of the pigment was evaluated. In order to evaluate antibacterial activity of the samples, Listeria monocytogenes, Staphylococcus aureus, Streptococcus iniae, Bacillus subtilis (Gram positive), Yersinia ruckeri, Escherichia coli and Enterobacter aerogenes (Gram negative) were used. The results showed that the antioxidant activity of nanocapsules carrying astaxanthin is significantly higher than the free form of pigment (p<0.05); In addition, this activity was improved by increasing the concentration of samples from 100 to 200 µg/ml (p<0.05). By astaxanthin nanoencapsulation, the diameter of non-growth zone of the studied bacteria increased (p<0.05), but minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the pigment and its carrier nanocapsules decreased (p<0.05). According to the results of zone of inhibition, Gram positive (except Listeria monocytogenes) and Gram negative bacteria were resistant up to concentrations of 60 and 80 µg/ml of samples, respectively. In the following, the MIC and MBC of the pigment (free and nanoencapsulated forms) for the seven bacteria ranged from 50 to 400 and 100 to 500 µg/ml, respectively. The results of evaluation the antioxidant and antibacterial activities of nanocapsules carrying astaxanthin during storage period (30 days at 4ºC) indicated stability and no significant change of these properties (p>0.05). According to the values of diameter of non-growth zone, MIC and MBC, Listeria monocytogenes was the most sensitive bacteria against astaxanthin and its carrier nanocapsules. Based on the findings, astaxanthin extracted from Haematococcus pluvialis has antioxidant and antibacterial activities, and these properties are improved by the pigment nanoencapsulation using maltodextrin-sodium caseinate coating.

Competition law is a newcomer to the legal system recently. A sound understanding of competition policy can provide us with sufficient bases to apply a fundamental and normative view of the issues of competition law. The difference in supervision and regulation determines how the market functions and in order to understand this difference one must understand competition policy. Competition policy may be based on governmental support for national production and industry or on a non-interventional and regulatory posture. Moreover, supervision, based on the principle of non-intervention in the market mechanism, is rooted in liberal ideas; however, regulation, whether as a rule or an exception, is based on the assertion that the market has been ineffective in attaining its goals. Therefore, the government will resort to interventions to regulate inefficiencies.  This paper aims to analyze Supervisory Authority in Implementing Competitive Policy by employing the description method. In this article the author tries to first delineate competition policy, its related requirements and imposed deviations to the market. Then, by defining the supervisory entity and clarifying its distinction from the regulatory institutions, the author considers the characteristics of an appropriate supervisory entity conducting a comparative study of this issue in Iran and the U.S.A. This form of Competition policy because of its applicable experiences which have been well described by recent scholarship is considered suitable for the native system.

هدف از این پژوهش، مقایسه ویژگی های زنان عضو صندوق با سایر زنان روستایی غیرعضو و مقایسه توسعه فعالیت های کارآفرینی زنان روستایی قبل و بعد از عضویت در صندوق کارآفرینی امید شهرستان لارستان است. جامعه آماری شامل تمام زنان روستایی عضو صندوق کارآفرینی امید شهرستان لارستان (440 نفر) از استان فارس بودند. طبق روش نمونه گیری طبقه ای تصادفی، پاسخگویان از دو گروه زنان عضو (111 نفر) و زنان غیرعضو (105 نفر) انتخاب شده و نهایتاً 216 نفر مورد مطالعه قرار گرفتند. این پژوهش با استفاده از روش پیمایش به جمع آوری اطلاعات مورد نیاز از طریق پرسشنامه پرداخته است. روایی صوری پرسشنامه توسط سه نفر از اساتید بخش ترویج و آموزش کشاورزی دانشگاه شیراز تأیید شد و برای پایایی آن نیز یک مطالعه راهنما در نمونه ای خارج از نمونه اصلی، انجام گرفت که دامنه ی ضرایب آلفای کرونباخ متغیرهای پژوهش، 74/0 تا 93/0 بدست آمد که مقادیر قابل قبولی است. نتایج یافته های پژوهش از مقایسه میانگین گروه های عضو و غیرعضو نشان داد که این دو گروه از نظر متغیرهای فردی-روانشناختی (سن، سطح سواد، روحیه کارآفرینی، خودکارآمدی و سطح آگاهی از طرح های صندوق کارآفرینی امید) و بهره مندی از آموزش های کارآفرینی، گرایش کارآفرینانه، شبکه سازی اجتماعی و سازمانی، توسعه فعالیت های کارآفرینی و پایداری فعالیت ها دارای تفاوت های معناداری هستند؛ اما از لحاظ سیاست های حمایتی دولت و فضای کسب وکار بین دو گروه تفاوتی مشاهده نشد. همچنین، مقایسه سطح توسعه فعالیت های کارآفرینانه نشان داد که بعد از عضویت در صندوق کارآفرینی امید، سطح توسعه فعالیت های کارآفرینانه زنان بهبود یافته است.

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