The phone subscription agreement is one of the most important contracts between the subscriber (customer) and telecommunication companies to receive the communication services that has a vital role in human life today. This paper which has been provided with analytic-descriptive, the nature of the oldest meanwhile the most important and current subscriber agreement with telecommunication means the postpaid phone subscription agreement has been examined. Based on this with analyzing the purport of this contract, it has been challenged the way of the relationship between the subscriber and telecommunication and customizing the telecommunication equipment (instruments) to it and how calculating the expenses relating to this contract, the opinions which think that the subscription agreement is inclusively leasing (Arabic:اجاره ijarah) and sale (Arabic: بیع bay') contract and it is accepted the opinion of the composite (compound) contract for determining the nature of this contract. Also for the clarification of the quality and nature of the compound contract, meanwhile accepting the Islamic traditional report about the sale of rights and interests (benefits) and stating that the inadequacy (lack) of the uncertain (brief) knowledge to the consideration for avoidance of the doubt of gharar (Arabic: غرر meaning risky transaction) in the sale of the benefits, for the solution of the doubt in the consideration in the section of the inconstant (variable) expenses of in this contract (printed in periodic bills), the title of sulh (meaning: settlement and resolution) contract is suggested and accepted. Lastly, the acceptable opinion of this research for the nature of the postpaid phone subscription agreement is a contract composed of the sale of subscription fee, the sale of the constant contact and the settlement (sulh) on interests (benefits).

casualties caused by traffic accidents have been one of the important social issues of the country in the last few decades. Although, this phenomenon has been widely researched, but it has rarely been considered longitudinally and in terms of macroeconomic socio-economic indicators. The main purpose of this study was to investigate the casualties caused by traffic accidents in terms of socio-economic indicators, mobile phone subscription, inflation rate, labor force participation rate, literacy rate, urban population growth, GDP per capita and the number of emergency centers in the country.

This research is of quantitative-longitudinal type, which has been done by time series method and it has considered the relationship of variables in the period of 1370-1399. The required data have been collected from Iran Statistics Center, Forensic Medicine Organization and World Bank. To investigate the short-term and long-term relationship, the autoregression model with distribution breaks has been used in Microfit software.

In the long term, with the increase in inflation rate, labor force participation rate, mobile phone subscription rate and per capita GDP increase, the casualties due to accidents have increased, but with the increase in the urban population and the number of emergency centers, the accident casualties have decreased. Is. In addition, literacy rate does not have a significant relationship with accident fatalities.

The results of this research showed that casualties caused by traffic accidents in Iran, as an acute social problem, are affected by macro indicators of economic and social development.

Coronavirus disease 2019 (COVID 19), which originated in December 2019, on January 30, 2020 was declared  by the World Health Organization as the sixth public health emergency from international concerns [1]. Since the onset of the disease in late 2019 to mid-June 2020, more than 8.5 million people around the world have been infected with COVID 19. Of these, more than 450,000 have died [2]. So far, six species of human coronavirus have been identified, most of which , like SARS in 2002 and MERS in 2012, cause mild respiratory illness [3]. During the spread of COVID 19 worldwide, people use social media to receive and exchange information [4]. With the advent of smartphones, widespread access to the Internet, and the availability of instant messaging applications, it has become clear that these communications can have numerous benefits for healthcare providers as well. WhatsApp is one of the instant messaging applications that is widely used in healthcare and is, therefore, a popular app [5]; it has about 1.5 billion users worldwide [6]. WhatsApp is compatible with all smartphone operating systems such as iPhone, Android, Windows phone [7]. This messenger allows its users to easily share text and video messages as well as media files and content with other users.  A,lso group chats and the participation of several users in calls for conversation are easily available in this messenger. WhatsApp communications can be done easily and internationally. WhatsApp is available for everyone for an annual subscription fee of $0.99 [6, 8]. In addition to major changes in people's daily lifestyles, social media has improved communication between patients and professionals by establishing fast multimedia communication, health education, social support, and better health decisions, so that WhatsApp has been used in cases such as drug therapy problems, drug and dietary supplements, emotional changes, lifestyle habits, social rights, physical symptoms, commitment to treatment, medical emergencies, oral health promotion and issues of dentistry [9]. According to a study by Kurubaran Ganasegeran et al., most health system employees understand the use of WhatsApp in health and clinical matters, and it has been observed that these messengers in clinical departments (approximately 61% of employees), clinics (about 60%), operating room (56%) and when calling the treatment staff (approximately 55%) have been used [8]. The World Health Organization also defines mobile (wireless) health as public health, supported by wireless devices such as mobile phones, monitoring devices, personal digital assistants (PDAs), and other wireless devices [10]. Given the prevalence of COVID 19 worldwide and the risk to all individuals, the use of WhatsApp Messenger to inform the latest announcements of the World Health Organization, public and regional health centers, health professionals, and researchers can have a significant impact on public health. The messenger can also be used to effectively communicate with members of the medical staff to resolve the questions and rumors, and avoid frequent visits to health centers that are high-risk areas. WhatsApp can also be contacted by friends and acquaintances using voice and video calls, which can probably reduce the psychological pressure of the quarantine and isolation to some extent.

P atents are one of the most important types of scientific and technological products that contain valuable information about invention, inventor or co-inventors, assignee, classification (IPC, CPC or ...), etc. This kind of information is often not published in journals and other information sources. There are databases dedicated to patents that collect patent information. Access to some of them, such as USPTO and WIPO database is free and others, such as the Derwent database, require subscription. In recent years, some scholarly and citations databases, usually dedicated to providing data on scientific works such as articles, books, etc., have also covered patents. These databases are available for free and subscription and can provide sophisticated search tools which allow simple search, advanced search, semantic search or patent number search, name of materials and chemical compounds and other search methods to obtain the required information from patents. Using advanced tools, it is possible to visualize and analyze patents to understand the development path of certain technologies. In this article, the most important databases providing patent information are introduced. These databases include lenz, Orbit, chemical abstracts service (SciFinder and PatentPAK), etc.

We are bombarded with numerous emails daily requesting to submit a paper, become a member of the editorial board, or attend a meeting. It implies that there should be a defect in the publishing business model that allows predatory journals to creep in and outnumber legitimate ones. Conventionally, the cost of publishing was covered by subscription (subscriptionbased). Budapest Open Access Initiative (1) was the first to declare open access to scholarly published articles in 2002, followed by the Bethesda Statement on Open Access Publishing (2) and Berlin Declaration on Open Access to Knowledge in the Sciences and Humanitiesin 2003 (3). The author-payer model is now called gold open access, in which the author is charged when the paper is accepted for publication.