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The zebrafish (Danio rerio) is a valuable animal model rapidly becoming more commonly used in pharmaceutical studies. Due to its low-cost maintenance and high breeding potential, the zebrafish is a suitable substitute for most adult rodents (mice and rats) in neuroscience research. It is widely used in various anxiety models. This species has been used to develop a conceptual framework for anxiety behavior studies with broad applications in the laboratory, including the study of herbal and chemical drugs. This review discusses the latest studies of anxiety-related behavior in the zebrafish model. [ABSTRACT FROM AUTHOR]

COVID-19 is a contagious disease that attacks many organs but the lungs are the main organs affected. The inflammasome activation results in the exacerbation of inflammatory response in infectious disease. The aim of this study is to investigate the formation and activity of the NLRP3 inflammasome complex and the histopathological changes caused by the coronavirus in the lung of deceased persons with COVID-19. In total, 10 corpses; 5 corpses with no history of any infectious diseases and COVID-19 and 5 corpses with the cause of death of COVID-19 were included in this study. Lung tissue samples were harvested during autopsy under safe conditions. Fresh tissues in each group were used to measure the genes expression and proteins level of NLRP3, ASC, Caspase-1, IL-1β, IL-6 and TNF-α and a routine hematoxylin and eosin staining was performed for histological assessment. Data are represented as the means ± SD. Statistical significance difference was accepted at a p-value less than 5%. The NLRP3, ASC, Caspase-1, IL-1β, IL-6 and TNF-α genes expression and proteins level were elevated in the lung of the COVID-19 group in comparison with the control group. Histological findings presented the increasing number of polymorphonuclear leukocytes, macrophages and also pulmonary fibrosis in the lungs of corpses with the cause of death of COVID-19. High expression of NLRP3 inflammasome components and its relation with the pathophysiology of the coronavirus-infected lung suggested that targeting the NLRP3 inflammasome could be helpful in achieving a more effective treatment in patients with COVID-19. [ABSTRACT FROM AUTHOR]

A methanol poisoning outbreak occurred in Iran during the initial months of coronavirus disease 2019 (COVID-19) pandemic. We aimed to evaluate the epidemiology of the outbreak in terms of hospitalizations and deaths. A cross-sectional linkage study was conducted based on the hospitalization data collected from thirteen referral toxicology centers throughout Iran as well as mortality data obtained from the Iranian Legal Medicine Organization (LMO). Patient data were extracted for all cases aged > 19 years with toxic alcohol poisoning during the study period from February until June 2020. A total of 795 patients were hospitalized due to methanol poisoning, of whom 84 died. Median [interquartile ratio; IQR] age was 32 [26, 40] years (range 19–91 years). Patients had generally ingested alcohol for recreational motives (653, 82.1%) while 3.1% (n = 25) had consumed alcohol-based hand sanitizers to prevent or cure COVID-19 infection. Age was significantly lower in survivors than in non-survivors (P < 0.001) and in patients without sequelae vs. with sequelae (P = 0.026). Twenty non-survivors presented with a Glasgow Coma Scale (GCS) score > 8, six of whom were completely alert on presentation to the emergency departments. The time from alcohol ingestion to hospital admission was not significantly different between provinces. In East Azerbaijan province, where hemodialysis was started within on average 60 min of admission, the rate of sequelae was 11.4% (compared to 19.6% average of other provinces)—equivalent to a reduction of the odds of sequelae by 2.1 times [95% CI 1.2, 3.7; p = 0.009]. Older patients were more prone to fatal outcome and sequelae, including visual disturbances. Early arrival at the hospital can facilitate timely diagnosis and treatment and may reduce long-term morbidity from methanol poisoning. Our data thus suggest the importance of raising public awareness of the risks and early symptoms of methanol intoxication. [ABSTRACT FROM AUTHOR]

Radiation-shielding of healthy tissue is mandatory in breast intraoperative electron radiotherapy (IOERT). In this regard, dedicated radioprotection disks have been introduced. The aim of this study was to evaluate and compare the performance of three radioprotection disks widely used for breast IOERT. A Monte Carlo simulation approach was used for this purpose. The considered disks included Al + Pb, PMMA + Copper, and PTFE + Steel. They were stimulated by means of the MCNPX Monte Carlo code at depths around R100 and R90 of different electron energies in a water phantom, and their impact on the dosimetric properties of the therapeutic beam was evaluated in both correct and upside down disk placements. The electron energy spectrum immediately above and below each disk was calculated and analyzed. Furthermore, performance characteristics of the studied disks such as backscatter factors (BSFs) and transmission factors (TFs) at different electron energies were determined and compared. The results show that the Al + Pb disk most effectively attenuates the beam, while at the same time exhibits maximum BSF values. Employing the PMMA + Copper disk can minimize the BSF value but at the expense of an increased TF. The Al + Pb disk showed the best performance from the radiation protection viewpoint, while its highest BSF values could lead to perturbation of dose homogeneity within the target volume. PTFE + Steel disk showed an intermediate performance regarding the electron backscattering and transmission among the studied disks. The reverse placement of each disk can substantially increase the BSF value as compared to the correct situation but had less impact on the TF value. [ABSTRACT FROM AUTHOR]

Evaluating the stray radiation around medical electron accelerators is a mandatory issue. Surveying the radiation leakage dose is important for patients, technicians, and health physicists, due to radiation protection aspects. Consequently, radiation leakage dose around the head of a mobile-dedicated intraoperative radiotherapy accelerator (LIAC), at different electron energies and field sizes have been evaluated in this study. More specifically, the MCNPX Monte Carlo code was used to model the LIAC head, connected applicator, and employed water phantom. Radiation leakage dose around the LIAC head was calculated for different energy and field sizes through tuning the Monte Carlo results to the practically measured doses. These measurements were performed using an Advance Markus ionization chamber inside an automated MP3-XS water phantom. The good agreement between the calculated dose distributions within the water tank and corresponding dose measurements show that the simulation model of the LIAC head is appropriate for radiation leakage assessment. The obtained radiation leakage dose distribution highly depends on the electron energy and applicator diameter. With increasing the electron energy, the leakage dose decreased, while increasing the field size increased the leakage dose. It is concluded that the rate of stray radiation and leakage dose around the LIAC head in both vertical and horizontal planes were acceptable according to the recommended radiation protection criteria. To meet the recommended dose limit (100 µSv/week for controlled areas), the maximum number of patients should be kept to four patients per week inside a standard and unshielded operating room. [ABSTRACT FROM AUTHOR]

Objective: This study aims to assess the impact of different image reconstruction methods on PET/CT quantitative volumetric and textural parameters and the inter-reconstruction variability of these measurements.Methods: A total of 25 oncology patients with 65 lesions (between 2017 and 2018) and a phantom with signal-to-background ratios (SBR) of 2 and 4 were included. All images were retrospectively reconstructed using OSEM, PSF only, TOF only, and TOFPSF with 3-, 5-, and 6.4-mm Gaussian filters. The metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were measured. The relative percent error (ΔMTV and ΔTLG) with respect to true values, volume recovery coefficients, and Dice similarity coefficient, as well as inter-reconstruction variabilities were quantified and assessed. In clinical scans, textural features (coefficient of variation, skewness, and kurtosis) were determined.Results: Among reconstruction methods, mean ΔMTV differed by -163.5 ± 14.1% to 6.3 ± 6.2% at SBR2 and -42.7 ± 36.7% to 8.6 ± 3.1 at SBR4. Dice similarity coefficient significantly increased by increasing SBR from 2 to 4, ranging from 25.7 to 83.4% between reconstruction methods. Mean ΔTLG was -12.0 ± 1.7 for diameters > 17 mm and -17.8 ± 7.8 for diameters ≤ 17 mm at SBR4. It was -31.7 ± 4.3 for diameters > 17 mm and -14.2 ± 5.8 for diameters ≤ 17 mm at SBR2. Textural features were prone to variations by reconstruction methods (p < 0.05).Conclusions: Inter-reconstruction variability was significantly affected by the target size, SBR, and cut-off threshold value. In small tumors, inter-reconstruction variability was noteworthy, and quantitative parameters were strongly affected. TOFPSF reconstruction with small filter size produced greater improvements in performance and accuracy in quantitative PET/CT imaging.Key Points: • Quantitative volumetric PET evaluation is critical for the analysis of tumors. • However, volumetric and textural evaluation is prone to important variations according to different image reconstruction settings. • TOFPSF reconstruction with small filter size improves quantitative analysis. [ABSTRACT FROM AUTHOR]

This paper develops an Enhanced Genetic Algorithm (GA) strategy in conjunction with a time-domain Spectral Finite Element Method (SFEM) for impact identification of framed structures. For this purpose, a spatial truss spectral element is proposed for impact response simulation. In this regard, Gauss-Lobatto-Legendre quadrature rules and points configuration are adopted to construct a diagonal matrix and to gain an optimum computational demands. A decimal and a mixed GA coding system are implemented to locate and re-construct the impact features, respectively. An improved GA-based fitness assessment is designed to significantly accelerate the convergence rate of the optimization strategy. The impact identification of two frame structures is investigated taking into account the influence of externally applied loading. It is concluded that, the proposed mixed coding GA strategy effectively overcomes the main drawbacks of classical GA approach. The developed SFEM is superior to conventional FEM because of its high order interpolation and integration rules. For large structures, impact localization is successfully accomplished very fast, which provides the excellent ability in developing an on-line health monitoring system. It is included that, the robustness of the proposed SFEM lies on the considerably higher computational efficiency in achieving the most accurate results with the less computational costs. [ABSTRACT FROM AUTHOR]

Laser shock peening (LSP) is known as a post processing surface treatment which can improve the mechanical properties of some materials. Shock waves are generated by confining the laser-induced plasma to cause a large pressure shock wave over a significant surface area. In the present study, effects of LSP on the electrochemical corrosion and micro hardness properties of 316L stainless steel alloy were investigated by changing the laser parameters such as the laser spot size, the average number of impacts, and the laser intensity. Since laser parameters do not cover the desired region of LSP, we have to use the proper design of experiment method, in which the D-optimal design of MATLAB was selected. Results revealed that by increase in irradiance, number of impacts and spot size of laser beam, improvement in the surface micro hardness, and corrosion resistance is achieved. Also, due to unexpected drop into the outcome of our experiments, it was found that the contamination of the transparent overlay and reduction of the absorption coefficient of the absorbent layer play a key role to reduce the efficiency of the mechanical impacts. So, by changing the experimental conditions, even better results are expected. [ABSTRACT FROM AUTHOR]

Simulation of heat transfer in soil under steady and unsteady situations requires reliable estimate of soil thermal conductivity (λ) at varying environmental conditions. In the current work several soil thermal conductivity predicting models including I) de Vries, II) Campbell, III) combined de Vries and Campbell and IV) de Vries-Nobre were evaluated for the four soils of coarse sand, sandy loam, loam and clay loam textured at varying in temperature and bulk density at low moisture range. Thermal conductivities measured by the cylindrical probe method served as the reference for models assessment. Results showed that approximately same thermal conductivities obtained by the five methods at low moisture range (θ ≤ 0.05 m/m). Also the de Vries and de Vries-Campbell models produced accurate than Campbell and de vries-Nobre models. The accuracy of the two models increased with soil compaction but decreased with temperature rise. Campbell model showed more reliability at higher (311.16 and 321.16 K) temperatures; but its accuracy declined with soil compaction in current work. It seems that assuming needle shape for the soil particles is far away from the reality whereas assuming spherical shapes may be more realistic and produced more satisfactory prediction of thermal conductivity. The compaction would alter particle arrangement and may increase the contact area of particles; and then make them behave more or less spherical shape.it seems thermal conductivity in solid particles increase via increasing in temperature. Since a modified mineral shape factor, g , was developed as a combination between sphere and needle according to geometric mean particle diameter as well as bulk density and temperature as modifying factors. This factor increased the accuracy of de Vries-Nobre model up to 10.37%. Regarding nonlinear regression model, moisture content, bulk density, temperature and quartz content demonstrated significant effect on soil thermal conductivity in our investigation. [ABSTRACT FROM AUTHOR]

This paper introduces a procedure where the free-scaled Legendre wavelets are improved for dynamic analysis of spatial trusses. The operational matrices of integration for free scales of Legendre wavelets are presented and applied for time history analysis. For this aim, a clear-cut formulation is derived from decomposition of the only transitional responses of structures. The free-scaled operational matrices of Legendre wavelets accurately transfer the second-ordered differential equations of motion into the corresponding algebraic equations. Accordingly, a simple procedure is developed to compute dynamic responses of large-scaled spatial trusses. The applicability and effectiveness of the proposed procedure using Legendre wavelets are demonstrated with two numerical applications. Subsequently, results were compared with those from common time integration schemes such as Wilson-θ, Newmark-β, central difference and Duhamel integration methods. It is deduced that because of the inherent shape functions of Legendre wavelets the dynamic analysis is optimally achieved with the highest accuracy, best computational competency and with the lowest storage capacity. [ABSTRACT FROM AUTHOR]

Barium strontium titanate (BST) (BaSrTiO) thin films have been extensively used in many dielectric devices such as dynamic random access memories (DRAMs). To optimize its characteristics, a microstructural control is essential. In this paper, BaSrTiO thin film has been deposited on the SiO/Si substrate by the pulsed laser deposition (PLD) technique at three different oxygen working pressures of 100, 220 and 350 mTorr. Then the deposited thin films at 100 mTorr oxygen pressure were annealed for 50 min in oxygen ambient at three different temperatures: 650, 720 and 800°C. The effect of oxygen working pressure during laser ablation and thermal treatment on the films was investigated by using X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis methods. X-ray photoelectron spectroscopy analysis was used to determine the surface chemical composition of the samples. The results indicate that the deposited BST film at low working pressure (100 mTorr) in PLD chamber shows a lower surface roughness than other working pressures (220 and 350 mTorr). The as-deposited films show an amorphous structure and would turn into polycrystalline structure at annealing temperature above 650°C. Increase of temperature would cause the formation of cubic and perovskite phases, improvement in crystalline peaks and also result in the decomposition of BST at high temperature (above 800°C). In addition, rising of temperature leads to the increase in size of grains and clusters. Therefore more roughness was found at higher temperatures as a result of a more heterogeneous growth and less tensions. [ABSTRACT FROM AUTHOR]

Electrical properties and electronic structure of BiCaFeMnO grown by pulsed-laser deposition on BaTiO/SiO/Si substrate were investigated. Results showed that Ca has drastic effect on symmetry of crystal and electrical poperties of BiFeO. On the other hand, Mn revealed to have more radical effect on optical properties and energy gap of the compound. XPS results represented that although Ca tend to decrease Fe valence state, Mn tends to stabilize it at 3+ (at least in this concentrations). UV-visible study yielded bandgap of 2.51-2.81 eV (at 300 K) for different concentrations of Ca and Mn. UV-visible spectra also revealed sub-bandgap defect transitions at 2.2 and 2.4 eV. Slave-particle approach has also been applied to elucidate nature of the metal-insulator transition. [ABSTRACT FROM AUTHOR]

The morphological characteristics as well the optical properties of Ca-doped BiFeO films grown by pulsed-laser deposition technique have been investigated. AFM images revealed that calcium has a radical effect on the surface features of BiFeO films. By utilizing spectrophotometer, transmission behaviour of the films was investigated. Local IV characteristics of the films disclosed about three orders of magnitude enhancement concerning electrical conductivity through Ca doping. X-ray photoelectron spectroscopy results revealed that Ca can reduce the valence state of iron in the compound. [ABSTRACT FROM AUTHOR]

ZnO nanostructures were synthesized through arc discharge of zinc electrodes in deionized (DI) water. X-ray diffraction (XRD) analysis of the prepared nanostructures indicates formation of crystalline ZnO of hexagonal lattice structures. Transmission electron microscopy (TEM) images illustrate rod-like as well as semi spherical ZnO nanoparticles with 15–20 nm diameter range, which were formed during the discharge process with 5 A arc current. The average particle size was found to increase with the increasing arc current. X-ray photoelectron spectroscopy (XPS) analysis confirms formation of ZnO at the surface of the nanoparticles. Surface area of the sample prepared at 5 A arc current, measured by BET analysis, was 34 m/g. Photodegradation of Rhodamine B (Rh. B) shows that the prepared samples at lower currents have a higher photocatalytic activity due to larger surface area and smaller particle size. [ABSTRACT FROM AUTHOR]

We report a simple, inexpensive and one-step synthesis route of colloidal gold nanoparticles using arc discharge between titanium electrodes in HAuCl4 solution achieving long-time stability. Gold nanoparticles of 8 nm diameter were formed during reduction of HAuCl4 in the plasma discharge zone. The resulting nanoparticles were characterized using UV–Vis spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Optical absorption spectroscopy of as prepared samples at 15 A arc current in HAuCl4 solution shows a surface plasmon resonance around 550 nm. It was found that sodium citrate acts as a stabilizer and surface capping agent of the colloidal nanoparticles. SEM images exhibit the increase of reduced nanoparticles in 4 minutes arc duration compared with 1 minute arc duration. A TEM image of the sample prepared at 4 minutes arc duration shows a narrow size distribution with 8 nm mean particle size. The plasmonic peak intensity of as prepared gold nanoparticles in 1 minute arc duration gradually increases due to seed mediation up to 6 hours. [ABSTRACT FROM AUTHOR]