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In this paper, the design, performance and characterization of a low temperature argon plasma jet with a Surface Dielectric Barrier Discharge (SDBD)-like structure are presented. Based on this structure, the argon plasma jet is generated in a SDBD-like structure with a mixed electric field. SDBD-like structure, refers to the plasma jet generated by the surface dielectric barrier discharge. The effects of high frequency electric pulse as the main igniter for plasma jet generation and low frequency sinusoidal electric field in order to modify the dynamic behavior of plasma jet are investigated in this paper. The effect of these variations on the plasma jet along with the decrease in pulse repetition frequency were recorded by Schlieren imaging method. This study revealed the important role of decreasing the pulse repetition frequency in the mixed electric field in the SDBD-like plasma jet structure. Increasing the cross-sectional area of the plasma colliding with the target surface is the most important advantage of this structure for the generation of plasma jets. Also, the trend of decreasing plasma column continuity with increasing pulse repetition frequency is another result of this study. Under these conditions, the diameter of the cross section of the plasma jet increases to 9 mm without increasing the consumption of more electrical power and with equal jet length. Finally, the surface hydrophilicity was measured after treatment by plasma jet and the operation resulted in a super-hydrophilic surface. [ABSTRACT FROM AUTHOR]

In this paper, we present a new structure of applying two electrical power supplies to generate ionic wind. In this configuration, two power supplies were applied simultaneously with a modulated voltage to an electrohydrodynamic (EHD) system then corona discharge parameters and EHD thrust characterization was investigated by a corona dryer mechanism. The EHD thrust experiments were performed with a pin to plate and SDBD arrangements. The results show that with the simultaneous application of two power supplies the drying rate in a drop of water as a standard sample was greatly enhanced and the drying time was reduced. Thus, the total evaporation was occurred in 1 minute in the SDBD structure with a power of 7 watts and in 1.5 minutes in pin to plate structure with a power of 2.5 watts. Eventually, it was observed that the use of mixed electric fields enhances the ionic wind, hence increases the non-thermal evaporation process significantly. Furthermore, the drying rate has grown notably In SDBD configuration. [ABSTRACT FROM AUTHOR]

The current research was conducted to examine the effect of Artemisia dracunculus (AD) extract on growth performance, haemato‐immunological, biochemical parameters, and mucosal immunity in the rainbow trout (Oncorhynchus mykiss). The fish were fed with a diet supplemented with 0 (control), 1%, 2% and 3% AD for 8 weeks. The findings indicated that in all groups fed AD, especially at the 2% level, the growth parameters and survival rate significantly increased compared with the control group. Blood biochemical parameters, creatinine, glucose, lactate dehydrogenase (LDH), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and triglyceride were decreased significantly in AD‐treated groups. Total serum protein (TSP) levels, lysozyme (LYZ) and respiratory burst activities (RBA) were increased in the fish fed with AD. TSP levels, ALP and protease (PA) activities in the mucus were significantly increased following fish fed with AD. Increased in the total immunoglobulins (Ig) and superoxide dismutase (SOD) activity were observed in the fish fed with 3% AD. Fish fed with 2% AD showed the highest levels of alternative complement (ACH50) significantly. In addition, the mucus bactericidal activity was significantly increased in some treatments fed AD diet against Lactococcus garvieae and Aeromonas hydrophila. After infection with Yersinia ruckeri, there was a reduction in the mortality rate in the AD‐fed groups compared with the control group. Thus, it can be concluded that diets supplemented with AD can significantly impact diverse physiological parameters in fish, improving their growth performance, blood biochemical parameters and immune response. [ABSTRACT FROM AUTHOR]

In this paper, the dynamics and flow behaviour of an atmospheric argon plasma jet was studied in the new nozzle structure similar to the surface dielectric barrier discharge (SDBD) using the Schlieren imaging method. The effect of plasma jet driven by repetitive high‐voltage microsecond pulses with low‐frequency sinusoidal bias was measured qualitatively in a single mirror Schlieren optical system. The enhancement of plasma jet length and cross‐section of plasma jet with surface in this condition is due to highly turbulent flow of argon plasma jet in this structure. This study revealed the important role of SDBD structure and modulated electric field on the behaviour of plasma jet in a high diameter nozzle. In practice, this technique allows us to increase the jet length of the nozzle output to 5 cm and under these conditions, the diameter of the plasma jet cross‐section is increased to 8 mm, without increasing the electrical power consumption. Eventually, the hydrophilicity of the surface is also measured by the contact angle of a water droplet that decreases from 78° to 8° after surface treatment, implying we were able to reach a super‐hydrophilic surface with this plasma jet structure. [ABSTRACT FROM AUTHOR]

Visceral leishmaniasis (VL) is a neglected disease. Our retrospective study describes 38 clinical and epidemiological characteristics of VL in patients admitted to a paediatric hospital in Tehran, Iran, who came from different geographical regions, indicating that the disease has spread to most parts of the country. Some 76.3% of the children documented suffered with symptoms of the disease for two months before admission. [ABSTRACT FROM AUTHOR]

We demonstrate high quality-factor 1.5 mm diameter batch-fabricated microcrystalline diamond cylindrical resonators (CR) with quality-factors limited by thermoelastic damping (TED) and surface loss. Resonators were fabricated 2.6 and 5.3 µm thick in-situ boron-doped microcrystalline diamond films deposited using hot filament chemical vapor deposition. The quality-factor (Q) of as-fabricated CR's was found to increase with the resonator diameter and diamond thickness. Annealing the CRs at 700 °C in a nitrogen atmosphere led to a three-fold increase in Q, a result we attribute to thinning of the diamond layer via reaction with residual O2 in the annealing furnace. Post-anneal Q exceeding 0.5 million (528 000) was measured at the 19 kHz elliptical wineglass modes, producing a ring-down time of 8.9 s. A model for Q versus diamond thickness and resonance frequency is developed including the effects of TED and surface loss. Measured quality factors are shown to agree with the predictions of this model. [ABSTRACT FROM AUTHOR]

Background: Medical education system in Iran has an essential role in responding to scientific development targets from both education and research perspectives. Investigating future trends and analyzing how they interact with the medical education system helps increase awareness and give insight into the preferred future., Methods: The present qualitative study consists of Systematic reviews and interviews that have been analyzed using content analysis. Afterward, the themes and codes were visualized in the form of maps and presented in a focus group discussion of experts to define how medical education trends will impact scientific development., Results: The future trends of Iran's medical education system were classified into six groups: workplace changes, demographic changes, changes in concepts, the emergence of new players, structural changes in universities, and technology development. The next point is how they will influence science development. Their impact on science development is classified into five main groups or main streams of change of new financial models, open science, redesigning the research management, the role of universities, and capacity building., Conclusion: Our findings showed that redesigning the structure of medical education is the most important priority to make the system as agile as needed to capture the signs and act. New meanings and concepts should also be considered in restructuring, like power balance, competency-based and personalized education, cost-effectiveness, and openness., Competing Interests: The authors declare that they have no competing interests., (© 2023 Iran University of Medical Sciences.)