In this article, the detailed information was presented about azo-dyes, including a general description of this class of compounds, which included a historical overview, observations on the chemical structure of these compounds, particularly focusing on the azo group (-N=N-) responsible for their coloring properties. In addition, we provided a schematic of the first synthesized azo-compound. Furthermore, we mentioned the general properties of them and viewed a detailed explanation for the categorization of them either aliphatic or aromatic, subdivisions for each category or which category is the most widespread, and then illustrated the types for this class of organic compounds. The effective operator in these compounds called diazonium-sal

In this review of literature, the light will be concentrated on the role of stem cells as an approach in periodontal regeneration.

One of the most serious health disasters in recent memory is the COVID-19 epidemic. Several restriction rules have been forced to reduce the virus spreading. Masks that are properly fitted can help prevent the virus from spreading from the person wearing the mask to others. Masks alone will not protect against COVID-19; they must be used in conjunction with physical separation and avoidance of direct contact. The fast spread of this disease, as well as the growing usage of prevention methods, underscore the critical need for a shift in biometrics-based authentication schemes. Biometrics systems are affected differently depending on whether are used as one of the preventive techniques based on COVID-19 pandemic rules. This study provides an

Background: Postoperative pain is one of the main complications following impacted mandibular third molar (IMTM) surgery. Objectives: The aim of this study was to assess the effect of the local application of bupivacaine on reducing early postoperative pain following IMTM surgery. Material and methods: A prospective, single-blinded, randomized controlled study was conducted on 40 patients who had undergone the surgical removal of an IMTM under local anesthesia. In the study group (n = 20), absorbable gelatin sponge (AGS) soaked in 3 mL of 0.5% plain bupivacaine hydrochloride was locally applied in the post-extraction socket. In the control group (n = 20), AGS soaked in 3 mL of normal saline was used. Pain intensity was assessed using a pa

Abstract

The human mind knew the philosophy and logic in the ancient times, and the history afterwards, while the semiotics concept appeared in the modern time, and became a new knowledge field like the other knowledge fields. It deals, in its different concepts and references, with the processes that lead to and reveals the meaning through what is hidden in addition to what is disclosed. It is the result of human activity in its pragmatic and cognitive dimensions together. The semiotic token concept became a knowledge key to access all the study, research, and  investigation fields, due to its ability of description, explanation, and dismantling. The paper is divided into two sections preceded by a the

  Time represented a significant element in building any film story, despite its inability to express itself, but by employing the rest of the elements of the cinematic mediator language to express it. Time factor is present and manifested in all the details of the picture, and the more important is its presence in the event narration process. The narration totally depends on temporal structure in which it appears, which makes time a dominating element in the development of the narrative shapes and patterns. The narrative propositions have come to take new workings that time streams appeared that manipulate the time structure, reversing it, stopping it or making it fluctuate between the three levels of time, or repeating it or make