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THE EFFECT OF FINANCIAL LIBERALIZATION THROUGH THE GENERAL AGREEMENT ON TRADE AND SERVICES ON ECONOMIC GROWTH IN DEVELOPING COUNTRIES

Security and Risk in the Current Multicast Group Key Distribution Protocols

Author : Moutasem Shafa’amry

ABSTRACT

Multicast communications seem particularly well adapted for large scale commercial distribution applications, for example interactive distance-learning, the pay TV channels, board-meetings, group discussions, publish-subscribe systems, and secure videoconferencing. The security for this type of applications is essential for data transmission through an insecure network. A more difficult and challenging issue arises due to the multicast group membership being dynamic. Users can leave and join the groups, thus making the issue of group management more difficult in large-scale systems. Therefore, one of the most important issues in multicast security is the group key management. Key management mainly has to do with the distribution and update of keying material during the group life. Several approaches have been proposed by various authors to create and distribute the multicast group key in effective manner. There are different key management algorithms that facilitate efficient distribution and rekeying of the group key. These protocols normally add communication overhead as well as computation overhead at the both sides, the group key controller and the group members. Those schemes can be generally classified into three basic types, the centralized scheme, decentralized scheme and the distributed scheme. In this paper, we investigate the-state-of-art multicast group key management algorithms and protocols. We also provide the comparative analysis of the various algorithms, evaluating their features based on criteria containing the following elements: The algorithm properties, the type of costs, the secrecy, and the amount of storage. Additionally, the study explores the pros and cons of each scheme, providing conclusions and a guideline for a future development and work in securing multicast group communication. Keywords: Multicast security, key management, secure communication, secrecy, security, secure group communication

Link to read full paper :https://www.researchgate.net/publication/221875487_Security_and_Risk_in_the_Current_Multicast_Group_Key_Distribution_Protocols

The Impact of Financial Liberalization on Economic Growth: The Indirect Link

Foreign bank entry and financial development: New evidence on the cherry picking and foreign bank’s informational disadvantage phenomena in the MENA countries

The effect of low-level laser therapy during orthodontic movement: A preliminary study

Author : Sharif Ashkar, Maziar Mir and Mohamed Youssef

ABSTRACT

It has been emphasized that one of the most valuable treatment objectives in dental practice is to afford the patient a pain-free treatment. By the evolution of the laser applications, the dental committee aimed to achieve this goal without analgesic drugs and painful methods. Orthodontic treatment is one of these concerns, that one of the major components of patient to reject this treatment is the pain accompanied during the different treatment phases. Another great concern of the patient is not to get through prolonged periods of treatment. The aim of this study is to evaluate the effect of the low-level (GaAlAs) diode laser (809 nm, 100 mW) on the canine retraction during an orthodontic movement and to assess pain level during this treatment. A group of 15 adult patients with age ranging from 14 to 23 years attended the orthodontic department at Dental School, Damascus University. The treatment plan for these patients included extraction of the upper and lower first premolars because there was not enough space for a complete alignment or presence of biprotrusion. For each patient, this diagnosis was based on a standard orthodontic documentation with photographs, model casts, cephalometric, panorama, and superior premolar periapical radiographies. The orthodontic treatment was initiated 14 days after the premolar extraction with a standard 18 slot edgewise brackets [Rocky Mountain Company (RMO)]. The canine retraction was accomplished by using prefabricated Ricketts springs (RMO), in both upper and lower jaws. The right side of the upper and lower jaw was chosen to be irradiated with the laser, whereas the left side was considered the control without laser irradiation. The laser was applied with 0-, 3-, 7-, and 14-day intervals. The retraction spring was reactivated on day 21 for all sides. The amount of canine retraction was measured at this stage with a digital electronic caliper (Myoto, Japan) and compared each side of the relative jaw (i.e., upper left canine with upper right canine and lower left canine with lower right canine). The pain level was prompted by a patient questionnaire. The velocity of canine movement was significantly greater in the lased group than in the control group. The pain intensity was also at lower level in the lased group than in the control group throughout the retraction period. Our findings suggest that low-level laser therapy can highly accelerate tooth movement during orthodontic treatment and can also effectively reduce pain level.