Effect of alkaline ph on sealing ability of white mineral trioxide aggregate

Objectives: The aim of this study was to evaluate microleakage of white mineral trioxide aggregate (WMTA) after its exposure to a range of alkaline environments during hydration. Study Design: Seventy single-rooted teeth were divided into 4 experimental and 2 control groups. All the teeth were instrumented, and their apices were resected. Root-end cavities were filled with WMTA in the experimental groups. In the control groups, root-end cavities were not filled. Root-end fillings were exposed to alkaline environments with pH values of 7.4, 8.4, 9.4, or 10.4 for 3 days. Microleakage was evaluated by bovine serum albumin. Evaluations were carried out at 24-hour intervals for 80 days. Data were analyzed by one-way analysis of variance and a post hoc Tukey test at the 0.05 level of confidence. Results: The number of days (mean ± standard deviation) needed for color change at pH values of 7.4, 8.4, 9.4, and 10.4 were 78.53 ± 5.68, 80.00 ± 0.00, 68.93 ± 19.00, and 34.46 ± 12.73, respectively. The time needed for leakage to occur was significantly shorter in samples stored at a pH value of 10.4 (P<0.001). Conclusions: Within the limits of this study, it can be concluded that pH values greater than 9.4 may jeopardize the sealing ability of WMTA during hydration. © Medicina Oral S. L

A brief review on DNA vaccines in the era of COVID-19

This article provides a brief overview of DNA vaccines. First, the basic DNA vaccine design strategies are described, then specific issues related to the industrial production of DNA vaccines are discussed, including the production and purification of DNA products such as plasmid DNA, minicircle DNA, minimalistic, immunologically defined gene expression (MIDGE) and Doggybone (TM). The use of adjuvants to enhance the immunogenicity of DNA vaccines is then discussed. In addition, different delivery routes and several physical and chemical methods to increase the efficacy of DNA delivery into cells are explained. Recent preclinical and clinical trials of DNA vaccines for COVID-19 are then summarized. Lastly, the advantages and obstacles of DNA vaccines are discussed

Speculation Effects on Inflation in Iran Economy: TVP-FAVAR Model

Given the importance of inflation in Iran economy, scrutiny of inflation determinants is important .according to various studies, evaluation of determinants of inflation using standard VAR model, may lead to wrong conclusions and this is due to omitted variables bias in VAR model. For example, the problem of price puzzle in the empirical literature is one of these results. In this study, for a more accurate assessment of determinants of inflation in Iranian economy and forecasting inflation, instead of using FAVAR model with constant coefficients, we have employed TVP-FAVAR models and inflation has been modeled. In this model, the variables of GDP growth, growth of the monetary base, inflation, exchange rates and interest rates are considered as the main variables, and to estimate the non-observable variables of speculation section return, variables in the overall classification are modeled. Based on the results, the relationship between the variables change over time and conditions prevailing in the economy is effective on the influence of model variables on each other

The study of Factors Affecting the Export of Services Case study: Export of Technical and Engineering Services

In recent decades and especially in developing countries, the trade of services has faced an increasing trend. The export of services can improve trade balance, economic growth, employment as well as development of merchandise sector. This paper uses a descriptive and analytical approach and intends to evaluate performance and factors affecting the total export of services and particularly the export of technical and engineering services in OIC selected countries by applying panel data method. The results of estimating the performance indicators and comparative advantage of technical and engineering services export indicate that between years 1994 to 2010, Iran's position among these countries has improved. In our analysis, factors such as GDP per capita, real effective exchange rates, inflow of foreign investments, communication infrastructures and also being member of two trade blocs -ECO and D8- have significant and positive effect on the total export of services and also the export of engineering services. Thus, it is necessity for governmental institutions and private sector in Iran to plan and prepare to further develop the export of services

A brief review on DNA vaccines in the era of COVID-19

This article provides a brief overview of DNA vaccines. First, the basic DNA vaccine design strategies are described, then specific issues related to the industrial production of DNA vaccines are discussed, including the production and purification of DNA products such as plasmid DNA, minicircle DNA, minimalistic, immunologically defined gene expression (MIDGE) and Doggybone. The use of adjuvants to enhance the immunogenicity of DNA vaccines is then discussed. In addition, different delivery routes and several physical and chemical methods to increase the efficacy of DNA delivery into cells are explained. Recent preclinical and clinical trials of DNA vaccines for COVID-19 are then summarized. Lastly, the advantages and obstacles of DNA vaccines are discussed