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Using a three-dimensional numerical simulation, the dependencies of the electron cloud (virtual cathode) on the distance between the coils in the Polywell fusion reactor were examined. In the Polywell, the role of a stable and energetic virtual cathode is crucial for fusion. It is shown that by increasing the spacing coils, the electron confinement time increases initially and then remains constant. Using the simulation results, an optimum range for the spacing of coils was suggested, which leads to a longer and more effective confinement. The results obtained can be used to design future devices in order to have a more effective virtual cathode.

Abstract In this study, three-type paper supercapacitors based on the polyvinylidene fluoride (PVDF) and polyvinyl alcohol (PVA)/phosphoric acid (H3PO4) gel electrolytes and graphite nanoparticles (GNPs) electrodes have been fabricated. The gel electrolytes and electrodes films have been coated on the paper using push coating and then characterized by scanning electron microscopy (SEM). In two types of the paper supercapacitors, on the PVDF gel electrolyte film, a layer of PVA/water and BaTiO3 as a gel separator film has been coated. The specific capacitance of the paper supercapacitors using cyclic voltammetry (CV) and galvanostatic (charge–discharge) methods at the scan rates 20 and 150 mV s−1 have been investigated. The paper supercapacitor based on the BaTiO3 separator film showed higher specific capacitance (312 F g−1) compared to other samples. Also, using electrochemical impedance spectroscopy (EIS), the Nyquist and Bode curves of paper supercapacitors have been measured. For the paper supercapacitors based on the PVDF gel electrolyte film and BaTiO3 separator film using the Nyquist curves, the equivalent series resistance (ESR) was 306 Ω and 125 Ω, respectively. The paper supercapacitor based on BaTiO3 gel separator structure represents a new type of flexible supercapacitor with high performance that can be applied to electronic devices.

The current research was carried out to reveal the possible impacts of cold plasma on growth and physiology of wheat, as a new approach in plant science. Short and long-term impacts of different types of plasma (nitrogen and helium) with surface power density of 0.4 W cm-2, exposure times (15, 30, 60, and 120 s), and repetitions (1, 2, and 4 times with 24 h intervals) were evaluated. Single-time applied helium or nitrogen derived plasma significantly promoted total root and shoot lengths, in contrast to four times application, and the root system was more sensitive than the shoot one. In addition, seedlings were more sensitive to nitrogen derived plasma, compared with helium. The physiological responses to plasma treatment were analyzed via protein assay and peroxidase or phenylalanine ammonia lyase (PAL) activities measurements. Plasma generated signaling molecules, especially ozone, nitric oxide, and/or UV radiation induced promotions in the peroxidase and PAL activities as well as increase in protein content in leaves, especially when times and/or repetitions increased. Plants were perished by the nitrogen derived plasma at the highest exposure time and number of repetitions. However, the seedlings with inhibited growth not only caught up control one month after, but even the growth rate and biomass accumulation in the shoot and leaves were accelerated. Increased leaf soluble phenol content was recorded in plasma treated seedlings, especially at longer times and more repetitions.

In the present paper our aim is to investigate the effect of the spray time of the aluminium coated layers on the microstructure and corrosion behaviour. For this purpose we use the self-generated atmospheric plasma spray system for coating of aluminium on the carbon steel substrate. The different thicknesses of coating are created. To evaluate this effect we use the several analyses such as X-ray diffraction, scanning electron microscope, Micro hardness analysis by Vickers method, Adhesion strength analysis and electrochemical polarization test. The results are very interesting and show that due to low porosity, thicker layers are more homogeneous. The nanoparticles are observed in the thicker layers. The micro hardness tests show that the thicker layers have the better micro hardness value. Next, the adhesion strength tests illustrate that the highest adhesion strength are for longer spray times. On the other hand, the corrosion resistance behaviour of the coating is investigated by electrochemical polarization test. It is shown that the corrosion resistance increases by increasing the thickness due to low percentage of porosity. Keywords: Plasma spray, Thickness, Aluminium, Micro hardness, Corrosion resistance

The circuit parameters are investigated in a Mather-type plasma focus device. The experiments are performed in the SABALAN-I plasma focus facility (2 kJ, 20 kV, 10 µF). A 12-turn Rogowski coil is built and used to measure the time derivative of discharge current (dI/dt). The high pressure test has been performed in this work, as alternative technique to short circuit test to determine the machine circuit parameters and calibration factor of the Rogowski coil. The operating parameters are calculated by two methods and the results show that the relative error of determined parameters by method I, are very low in comparison to method II. Thus the method I produces more accurate results than method II. The high pressure test is operated with this assumption that no plasma motion and the circuit parameters may be estimated using R-L-C theory given that C0 is known. However, for a plasma focus, even at highest permissible pressure it is found that there is significant motion, so that estimated circuit parameters not accurate. So the Lee Model code is used in short circuit mode to generate the computed current trace for fitting to the current waveform was integrated from current derivative signal taken with Rogowski coil. Hence, the dynamics of plasma is accounted for into the estimation and the static bank parameters are determined accurately. Keywords: Plasma focus, Short circuit, High pressure, Rogowski coil, Circuit parameters, Lee Model

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.After a thorough investigation, the Editors have concluded that the acceptance of this article was based upon the positive advice of at least one illegitimate reviewer report. The report was submitted from an email account which was provided to the journal as a suggested reviewer during the submission of the article. Although purportedly a real reviewer account, the Editors have concluded that this was not of an appropriate, independent reviewer.This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identities were assumed and to the readers of the journal that this deception was not detected during the submission process.Further, the corresponding author was not able to explain the reason for adding the author M. Ghoranneviss to the revised article.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.After a thorough investigation, the Editors have concluded that the acceptance of this article was based upon the positive advice of at least one illegitimate reviewer report. The report was submitted from an email account which was provided to the journal as a suggested reviewer during the submission of the article. Although purportedly a real reviewer account, the Editors have concluded that this was not of an appropriate, independent reviewer.This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identities were assumed and to the readers of the journal that this deception was not detected during the submission process.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been retracted at the request of the Editors-in-Chief.The article duplicates significant parts of a paper that had already appeared in the Journal of Alloys and Compounds 648 (2015) 1104–1108 http://dx.doi.org/10.1016/j.jallcom.2015.07.063. One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper is not under consideration for publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents an abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

In this study, the three structures of the symmetric paper supercapacitors based on the carbon nanotubes (CNTs), graphite nanoparticles (GNPs) and graphene electrodes have been fabricated. In the supercapacitors was used of polyvinyl alcohol (PVA)/phosphoric acid (H3PO4) as a gel electrolyte and the BaTiO3 film as a separator film. The carbon nanomaterials, gel electrolyte surface, and electrode films were characterized by scanning electron microscopy (SEM) and transmission electron microscope (TEM). The specific capacitance of the symmetric paper supercapacitors using charge-discharge technique and C-V curves at the voltage scan rates 20 mV/s and 150 mV/s have been investigated. The symmetric paper supercapacitor based on the CNTs electrode showed higher specific capacitance 411 F g−1, compared to GNPs and graphene supercapacitors. Also by electrochemical impedance spectroscopy, the Nyquist curves of the symmetric paper supercapacitors have been plotted. For the symmetric paper supercapacitors based on the GNPs, graphene and CNTs electrodes the equivalent series resistance (ESR) resistance was 210 Ω, 96 Ω and 101 Ω respectively. The flexible symmetric paper supercapacitor based on BaTiO3/PVA/CNTs structure denotes a new type of the flexible supercapacitor that can be applied to the soft electronic.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.After a thorough investigation, the Editors have concluded that the acceptance of this article was based upon the positive advice of at least two illegitimate reviewer reports. The reports were submitted from email accounts which were provided to the journal as suggested reviewers during the submission of the article. Although purportedly real reviewer accounts, the Editors have concluded that these were not of appropriate, independent reviewers.This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identities were assumed and to the readers of the journal that this deception was not detected during the submission process.No reason has been provided for the addition of the author name A. Salar Elahi to the authorship of the revised article.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.After a thorough investigation, the Editors have concluded that the acceptance of this article was based upon the positive advice of at least one illegitimate reviewer report. The report was submitted from an email account which was provided to the journal as a suggested reviewer during the submission of the article. Although purportedly a real reviewer account, the Editors have concluded that this was not of an appropriate, independent reviewer.This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identities were assumed and to the readers of the journal that this deception was not detected during the submission process.

In this paper, we have studied the effect of working gas pressure on plasma pinch properties in a Mather type plasma focus (2 kJ, 20 kV, 10 μF), named SABALAN1. Argon at the various operating pressures ranging from 0.1-1.2 Torr has been used as working gas. The total current waveform has been measured for different pressures. Also, a numerical simulation was done using Lee model code to perform numerical experiments in SABALAN1. The numerical simulation was used to compute argon soft x-ray yield as a function of pressure, to anticipate the maximum soft x-ray efficiency at optimum operating gas pressure. The Lee model was configured for SABALAN1, by fitting a simulated discharge current waveform against a measured discharge current waveform was obtained by numerically integrating the output of a dI/dt calibrated Rogowski coil. The experimental and simulation curves for plasma pinch properties have been plotted. Some of the dynamic parameters of the plasma and the characteristics of the plasma pinch have been displayed at different argon pressures in two tables. In addition, the chart of the normalized parameters of the plasma pinch has been plotted in terms of pressure. The results of experimentally measured and numerical simulation show that better pinches with attention to their plasma pinch characteristics, generally were dependent on pressure and the best pinch is obtained at 0.6-0.7 Torr for argon at 14 kV in SABALAN1. Furthermore, in high pressures (higher than 0.7 Torr in our experiments), the discharge current can behave as short circuit discharge and resembles that of a simple L-C-R discharge which is a damped sinusoidal. Comparison of the experimental and numerical curves shows sensible agreement in some plasma pinch properties such as the time to pinch and depth of focus. The results from charts and tables have been discussed.

One of the best ways to get information about plasma and interactions within it, is the study on visible light emitted from plasma. Detection of the emission spectrum from plasma leads to identify the spectral lines of ions and impurities inside the plasma and measurement of all related parameters to ion flux such as velocity and temperature. The first measurement of impurities into the IR-T1 tokamak plasma is done by spectroscopic technique. The CCD-based spectrometer device with the wavelength range of 400-550 nm is used to detection the spectrum emitted from the plasma. The impurities into the plasma in the intended wavelength range are identified. Furthermore, the Doppler broadening of the most intense peaks of impurities and their temperatures are measured. The methods in this paper can be used on all fusion devices.

The first results of the movable multipurpose probe (MPP) experiments performed on the IR-T1 Tokamak are presented. For this purpose, a moveable MPP was designed, constructed, and installed on the IR-T1 Tokamak for the first time. MPP can measure radial variation of floating potential and ion saturation current, electrostatic fluctuation, magnetic fluctuation, and flow velocity simultaneously. The relation between gradient of Reynolds stress and poloidal particle flux can be investigated by MPP. It can measure the radial variation of radial electric field and poloidal electric field. The most advantage of MPP is to measure electric and magnetic plasma fluctuations simultaneously. MPP is composed of three sections: electrical part, magnetic part, and flow measurement section. This is a compact probe in which do not disturb plasma. The results are presented and discussed.

We have reviewed the deposition of titanium nitride (TiN) thin films on stainless steel substrates by a DC magnetron sputtering method and annealing at different annealing temperatures of 500, 600, and 700°C for 120 min in nitrogen/argon atmospheres. Effects of annealing temperatures on the structural and the optical properties of TiN films were investigated using X-ray diffraction (XRD), atomic force microscope (AFM), field emission scanning electron microscopy (FESEM), and UV-VIS spectrophotometer. Our experimental studies reveal that the annealing temperature appreciably affected the structures, crystallite sizes, and reflection of the films. By increasing the annealing temperature to 700°C crystallinity and reflection of the film increase. These results suggest that annealed TiN films can be good candidate for tokamak first wall due to their structural and optical properties.

Discovery of the laser in 1960 hopes were based on using its very high energy concentration within very short pulses of time and very small volumes for energy generation from nuclear fusion as “Inertial Fusion Energy” (IFE), parallel to the efforts to produce energy from “Magnetic Confinement Fusion” (MCF), by burning deuterium-tritium (DT) in high temperature plasmas to helium. Over the years the fusion gain was increased by a number of magnitudes and has reached nearly break-even after numerous difficulties in physics and technology had been solved. After briefly summarizing laser driven IFE, we report how the recently developed lasers with pulses of petawatt power and picosecond duration may open new alternatives for IFE with the goal to possibly ignite solid or low compressed DT fuel thereby creating a simplified reactor scheme. Ultrahigh acceleration of plasma blocks after irradiation of picosecond (PS) laser pulses of around terawatt (TW) power in the range of 1020 cm/s2 was discovered by Sauerbrey (1996) as measured by Doppler effect where the laser intensity was up to about 1018 W/cm2. This is several orders of magnitude higher than acceleration by irradiation based on thermal interaction of lasers has produced.

Nanocrystalline Pb1−3x/2GdxTiO3 (where x=0.01) abbreviated as PGT has been synthesised by high energy ball milling at room temperature. Milling was continuous and X-ray analysis shows that single phase tetragonal structure of nanocrystalline PGT was formed after 15 h milling. The average crystallite size was found to be 17 nm. The frequency dependent ac conductivity of the PGT ceramic was studied in the range 100–525°C. Complex impedance analysis suggested the dielectric relaxation to be of non-Debye type. The activation energy was found to be 1.04 ev. The mechanism of charge transport in nanocrystalline PGT was successfully explained by correlated hopping model.

In this work the surface of (4 0 0) p-type Si wafers is bombarded with 29?keV nitrogen ions at various ion beam fluency varied from 1016to 1018?ions/cm2and the results are investigated. Si3N4film with orthorhombic structure is formed on silicon surface with cubic structure while the lattice parameter of the generated layer is not affected by change of nitrogen ion beam dose. RMS roughness of implanted samples increases by increasing the nitrogen dose, specially when the dose is more than 3?1017?ions/cm2. Surface resistivity of samples is increased by increasing the dose of ion beam. Although changes in the transmission of implanted samples does not differ very much in comparison with row sample but reflection of implanted samples decrease about 60% for the electromagnetic wave in the range of 200 to 1500?nm. Absorption coefficient of samples is obtained and the band gap energy of samples is calculated. It is observed that formation of defect levels changes the magnitude of band gap energy. [ABSTRACT FROM AUTHOR]

The titanium oxide (TiO2) nanotubes have attracted attention for their use in dye-sensitized solar cells as photoanode. In this study semiconducting cadmium sulfide (CdS) nanoparticles are grown on top opened TiO2nanotubes arrays by radio-frequency magnetron sputtering. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and diffuse reflection spectra are used to study structural, morphological and optical properties of the CdS/TiO2bilayer. [ABSTRACT FROM AUTHOR]

In the present investigation, Ni50Ti25Al25 (at.%) mechanically alloyed powder is deposited on carbon steel substrate. Before the coating process, the substrate is heated to temperature ranging from room temperature to 400 °C. The microstructure, porosity, microhardness, adhesion strength, and corrosion behavior of the coating are investigated at different substrate temperatures. Results show that coating porosity is lower on high temperature surface. Microhardness and adhesion strength of the deposition layer on the substrate without preheating have lower values than with preheating. The polarization test result shows that corrosion performance of the coating is dependent on micro cracks and porosities and the increasing of substrate temperature can improve the quality of coating and corrosion performance. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanosheet, nanorod and nanotubes are synthesized using chemical vapor deposition (CVD) and anodizing processes. TiO2 nanosheets are grown on Ti foil which is coated with Au catalyst in CVD, TiO2nanorods are synthesized on treated Ti foil with HCl by CVD, and TiO2nanotubes are prepared by the three-step anodization method. Scanning electron microscopy shows the final TiO2structures prepared using three processes with three different morphologies of nanosheet, nanorod and nanotube. X-ray diffraction verifies the presence of TiO2. TiO2sheets and rods are crystalized in rutile phase, and TiO2 tubes after annealing turn into the anatase crystal phase. The optical investigations carried out by diffuse reflection spectroscopy reveal that the morphology of TiO2nanostructures influencing their optical response and band gap energy of TiO2is changed for different TiO2nanostructures. [ABSTRACT FROM AUTHOR]

The investigation of runaway electrons is expanded by different methods. The aim of this study is to show sawtooth oscillations of hard x-ray emission and with the help of sawtooth oscillations to obtain radial diffusion coefficient and magnetic fluctuations. In the same way, the hard x-ray spectral evaluation is compared in several time intervals and it is shown that during discharge, the energy of the runaway electrons is less than 200 keV. Also, for typical plasmas, population of runaway electrons is measured at seven time intervals of 5 ms and temporal evaluation of runaway electron mean energy. The sawtooth-like shape is observed in the hard x-ray range (10–1000 keV). By the sawtooth oscillation method, the RE diffusion coefficient in radial transport in the IR-T1 plasma is . The magnetic field fluctuation due to magnetic diffusionis given as . [ABSTRACT FROM AUTHOR]

Since runaway electrons and magnetohydrodynamics activity can contribute to serious damage and energy losses in tokamaks, the effect of an external electric field on runaway electrons and hard x-ray spectra is investigated. Parameters such as the plasma current, the hard x-ray photons count and the mean energy of runaway electrons are measured. Positive and negative voltages of 300 V are applied at 10 ms after the plasma initiation (while the plasma is forming), at 15 ms (while the plasma is stable) and at 20 ms (while the plasma is fading away) to attain the most effective time of applying the external electric field. The number of hard x-ray photons has the most changes in the range of 0–200 keV when the external electric fields are applied. Also in the duration of 20–30 ms of plasma the greatest number of hard x-ray spectra is detected. When the external electric fields are applied, the mean energy of runaway electrons reduces significantly, especially at 15 ms (while the plasma is stable). [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) is one of the most promising transparent conducting oxide materials, which is widely used in thin film gas sensors. We investigate the dependence of the deposition time on structural, morphological and hydrogen gas sensing properties of SnO2 thin films synthesized by dc magnetron sputtering. The deposited samples are characterized by XRD, SEM, AFM, surface area measurements and surface profiler. Also the H2 gas sensing properties of SnO2 deposited samples are performed against a wide range of operating temperature. The XRD analysis demonstrates that the degree of crystallinity of the deposited SnO2 films strongly depends on the deposition time. SEM and AFM analyses reveal that the size of nanoparticles or agglomerates, and both average and rms surface roughness is enhanced with the increasing deposition time. Also gas sensors based on these SnO2 nanolayers show an acceptable response to hydrogen at various operating temperatures. [ABSTRACT FROM AUTHOR]

In this paper we present the fabrication of cadmium telluride (CdTe) nanostructures by means of RF magnetron sputtering followed by low-energy ion implantation and post-thermal treatment. We have thoroughly studied the structural, optical, and morphological properties of these nanostructures. The effects of nitrogen ion bombardment on the structural parameters of CdTe nanostructures such as crystal size, microstrain, and dislocation density have been examined. From x-ray diffractometer (XRD) analysis it could be deduced that N+ ion fluence and annealing treatment helps to form (3 0 0) orientation in the crystalline structure of cadmium-telluride films. Fluctuations in optical properties like the optical band gap and absorption coefficient as a function of N+ ion fluences have been observed. The annealing of the sample irradiated by a dose of 1018 ions cm−2 has led to great enhancement in the optical absorption over a wide range of wavelengths with a thickness of 250 nm. The enhanced absorption is significantly higher than the observed value in the original CdTe layer with a thickness of 3 μm. Surface properties such as structure, grain size and roughness are noticeably affected by varying the nitrogen fluences. It is speculated that nitrogen bombardment and post-annealing treatment results in a smaller optical band gap, which in turn leads to higher absorption. Nitrogen bombardment is found to be a promising method to increase efficiency of thin film solar cells. [ABSTRACT FROM AUTHOR]

The effect of the positive bias on Reynolds stress (RS) and its effect on the radial turbulent transport at the edge plasma (r/a = 0.9) and scrape-off layer (SOL) region of plasma in tokamak are investigated. The radial and poloidal electric fields (Er, Ep) and ion saturation current (Is) are measured by multi-purpose probe (MPP). This probe is fabricated and constructed for the first time in the IR-T1 tokamak. The most advantage of this probe is that the variations of Er and Ep can be measured in different radii at the single shot. Thus the information of different radii can be compared with high precision. The bias voltage is fixed at Vbias = 200 V and it has been applied with the limiter bias that is fixed in r/a = 0.9. Moreover, the phase difference between radial and poloidal electric fields, and temporal evolution of the RS spectrum detected by MPP are calculated. RS magnitude on the edge (r/a = 0.9) is more than its value in the SOL (r/a = 1.02). With the applied bias 200 V, RS and the magnitude of the phase difference between Er and Ep are increased, while the radial turbulent transport is decreased simultaneously. Thus it can be concluded that RS affects radial turbulence. Temporal evolution of the RS spectrum shows that the frequency of RS is increased and reaches its highest value at r/a = 0.9 in the presence of bias. [ABSTRACT FROM AUTHOR]

The effect of time of applied bias on the edge turbulent transport is analyzed by the multi-fractal detrend fluctuation analysis (MF-DFA) method in the IR-T1 tokamak. The generalized Hurst exponents and the multifractal spectrum are computed by this method. The MF-DFA method is applied to the fluctuation of gradient of floating potential time series collected by a multipurpose probe. The monofractality or multifractality of the time series can be detected by generalized exponent. The multifractal spectrum describes the singularity content of the process. The results show that with applying bias to the plasma at different times (t = 15 ms, 18 ms and 22 ms), the degree of multifractality changes. It reaches the minimum when the bias is applied at t = 18 ms. The multifractality source of data is investigated by the surrogate method (phase randomization techniques). The surrogate method can destroy the different types of correlations in all the sizes of fluctuations. The results show that the long-range correlation contributes more to multifractality than the fat tail distribution. [ABSTRACT FROM AUTHOR]

The effects of the argon gas pressure, charging voltage and anode shape on the current sheath dynamics in a low energy (4.9 kJ) Mather type plasma focus (PF) were investigated. The formation and dynamics of the current sheath were monitored by using two magnetic probes, which were inserted radially and axially to explore the evolution of the plasma sheath and to estimate the range of its velocity during the break-down and run-down phases. The radial magnetic probe measurements showed a rather constant current sheath velocity near the insulator, which was more sensitive to the variations of the gas pressure than the charging voltage, and the current sheath did not lose its uniformity by expanding away from the insulator during the break-down phase. The results found from the axial magnetic probe signals revealed a higher current sheath velocity inside the step region of the step anode than the cylindrical one. The simulated axial current sheath trajectories (Lee's model) that were obtained after the fitting process of the current signals showed good agreement both for the cylindrical anode throughout the run-down phase and the step anode before the step region. Inside the step region, the separation between the simulated and the experimental trajectories of the step anode was increased at greater axial distances. [ABSTRACT FROM AUTHOR]

Sterilization of saffron packaging and maintaining the quality of saffron content are the main priorities in saffron preservation. Common modalities do not offer lasting saffron preservation and it is urgent to develop novel packaging approaches from renewable resources and prevent packaging waste. Here, simultaneous decontamination and quality maintenance of saffron is demonstrated, for the first time, through the synergistic application of nano-clay-loaded carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA) nanocomposites (CNCs) and cold plasmas (CP). Compared to the separate uses of CP and CMC/PVA/nano clay, our results confirm the synergies between CP and CMC/PVA/nano clay cause complete inactivation of Escherichia coli bacteria, while not significantly affecting the concentrations of the essential saffron components (safranal, crocin, and picrocrocin). Overall, the CP-treated CMC/PVA/nano clay fosters saffron preservation, through contamination removal and quality maintenance of the food product. The synergistic application of CP and CMC/PVA/nano clay thus represents a promising strategy for packaging, sterilization, and preservation of high-value food products., (© 2022. The Author(s).)

There is a strong and ever-escalating need for sterilization tools that are effective against a broad range of pathogenic microorganisms. To address this issue, this study evaluates the inactivation potential of arc and pulsed spark plasma discharges on Pseudomonas aeruginosa, Staphylococcus aureus, Microsporum canis, Trichophyton mentagrophytes, and Candida albicans microorganisms. Our results show that the electrical discharge plasma systems are effective in the inactivation of pathogenic microorganisms. The inactivation of the considered strains was greatly affected by the type of microorganisms. Higher viability losses of the pathogenic strains were observed in bacterial strains than in the fungal strains. Moreover, in the case of fungal strains, the population of C. albicans was decreased the most, followed by Trichophyton mentagrophyte, while the population of Microsporum canis was decreased the least. Besides, the arc discharge system was compared with the pulsed spark discharge system. It can be obtained from the results that the pulsed spark discharge treatment successfully enhanced the reduction of the pathogenic cells more than the arc discharge treatment. The higher efficiency of the pulsed spark discharge is due to the generation of discharge streamers on the water surface. The SEM analyses showed that electrical discharge plasmas produced serious damage to pathogenic eukaryotic and prokaryotic microorganisms. Also, the plasma-induced changes in pH values and temperature values were measured. The pulsed spark discharge-treated samples have more significant changes in pH value while arc discharge-treated samples have larger temperature changes., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: For many years, the chemotherapeutic agent doxorubicin (DOX) has been used to treat various cancers; however, DOX initiates several critical adverse effects. Many studies have reported that non-thermal atmospheric pressure plasma can provide novel, but challenging, treatment strategies for cancer patients. To date, tissues and cells have been treated with plasma-activated medium (PAM) as a practical therapy. Consequently, due to the harmful adverse effects of DOX, we were motivated to elucidate the impact of PAM in the presence of DOX on MCF-7 cell proliferation., Methods: MTT assay, N-acetyl-L-cysteine (NAC) assay, and flow cytometry analysis were utilized in this research., Results: The results demonstrated that 0.45 µM DOX combined with 3-min PAM significantly induced apoptosis (p< 0.01) through intracellular ROS generation in MCF-7 when compared with 0.45 µM DOX alone or 3-min PAM alone. In contrast, after treatment with 0.45 µM DOX plus 4-min PAM, cell necrosis was increased. Hence, DOX combined with 4-min PAM has cytotoxic effects with different mechanisms than 4-min PAM alone, in which the number of apoptotic cells increases., Conclusion: Although further investigations are crucial, low doses of DOX plus 3-min PAM could be a promising strategy for cancer therapy. The findings from this research may offer advantageous and innovative clinical strategies for cancer therapy using PAM.

Objective: In recent years many researchers applied cold plasma for wound healing. The cold plasma is irradiated on the surface of wound. In this paper the effect of irradiation of cold plasma on the skin for healing of injured tissue which is located inside body, such as tendon, is evaluated., Methods: The male, white New Zealand, (20-week-old) were selected. Aloxan injection induced for diabetes induction and a week later the blood glucose level was measured. The standard tendon injury was created. The rabbits was divided in 3 groups. Control group, Plasma treated group at 5 kv, plasma treated group at 10 kv. Cold plasma was applied to the rabbits for 21 days., Results: After 21 days the tendon tissue were considered histologically. The results show that inflammatory cells were significantly lower in the tendon treated with cold plasma at 10 kv than the others, which confirms that cold plasma treatment reduce the inflammation phase. Cold plasma treatment led to increase neovascularation and collagen production., Conclusion: The results of this study confirm that the cold plasma treatment of skin has positive effect on healing of tissue inside body., Competing Interests: Conflict of interestNone., (© Springer Nature Switzerland AG 2021.)

Purpose: The healing process is impaired in diabetic wounds like the other types of chronic wounds. Cytokines, and growth factors are valuable candidates for determination of wound vitality or duration. The aim of this study is to introduce a beneficial method to stop the inflammatory phase and infection in the wound healing process for accelerating the treatment of diabetic foot ulcers., Methods: As a randomized controlled trial, 44 patients with diabetic foot ulcers were selected and randomized. Twenty-two patients received standard care and rest of them received SC (standard care) + CAP (cold atmospheric plasma), n  = 22). Clinical examination was performed to assess the status of peripheral nerves and arteries for all patients. Cold plasma jet was used as a source of helium gas plasma generator. Plasma was irradiated on the wound 5 min, 3 times a week for 3 consecutive weeks., Results: Applying a plasma jet was effective in wound healing. The level of inflammatory cytokines was changed. Moreover, after applying plasma the mean expression of these variables was significantly decreased ( P  = 0.001). Following the plasma treatment, the level of cytokines such as IL-1 (39.44 ± 7.67), IL-8 (368.30 ± 82.43), INF-γ (17.03 ± 2.62), TNFα (22.75 ± 4.02) has decreased, inflammatory factors have ameliorated over three weeks, and accelerate wound healing. After CAP exposure, the mean of the mean fraction of bacterial load counts was significantly decreased., Conclusion: The effect of plasma irradiation on infectious diabetic foot ulcer was decreased bacterial load then accelerated wound healing by effecting on inflammatory phase in diabetic foot ulcers., Competing Interests: Conflict of interest disclosuresThe authors have no conflict of interest to disclose., (© Springer Nature Switzerland AG 2020.)

Cold atmospheric plasma (CAP) was shown to decrease bacterial load in chronic wounds. It was also presented as a novel approach to healing wounds in both in vitro and in vivo experiments. We aimed to examine the first randomized clinical trial for the use of CAP in diabetic foot ulcers. Patients (n = 44) were randomly double-blinded, and assigned to receive standard care (SC, n = 22) without or with CAP, to be applied three times a week for three consecutive weeks (SC + CAP, n = 22), using block randomization with mixing block sizes of four. The trial was conducted at the Diabetes Research Center in Tehran, Iran. CAP was generated from ionized helium gas in ambient air, and driven by a high voltage (10 kV) and high frequency (6 kHz) power supply. Primary outcomes were wound size, number of cases reaching wound size of <0.5, and a bacterial load after over three weeks of treatment. CAP treatment effectively reduced the fraction of wound size (p = 0.02). After three weeks, the wounds to reach fraction wound size of ≤0.5 was significantly greater in the SC + CAP group (77.3%) compared to the SC group (36.4%) (p = 0.006). The mean fraction of bacterial load counted in each session 'after CAP exposure' was significantly less than 'before exposure' measures. CAP can be an efficient method to accelerate wound healing in diabetic foot ulcers, with immediate antiseptic effects that do not seem to last long.

Determining surface topography of different tissues of the molar tooth with novel analytical methods has opened new horizons in dental surface measurements which characterize tooth surface quality in dentistry. Studying surface topological measurements and comparing surface morphology of hard tissue of the molar tooth are the ultimate goals of the present study. Ten molar teeth have been chosen for investigating their surface characteristics through image processing techniques. The power spectral density (PSD) and fast Fourier transform algorithms of every molar tooth containing enamel, dentin, and cementum have determined that the characterization of surface profiles is possible. As can be seen, PSD along with fractal dimensions leads to good results for teeth surface topography. Moreover, PSD angular plot assures appropriate description of surface., (© 2019 Wiley Periodicals, Inc.)