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In this study, the morphological properties and micro-roughness of chromium thin film prepared by thermal evaporation technique and confirmed via EDS analysis are examined on different substrates of BK7, Silicon (Si), and glass using atomic force microscope analysis (AFM). Analysis of amplitude parameters, Minkowski functionals, and films' spatial microtexture extracted from AFM analysis showed the difference between glass substrate and the other two (BK7 and Si) substrates for the growth of chromium thin films. In addition, we observed robust signatures of multifractality of the Cr thin films deposited on all substrates we studied. Moreover, we highlight that the Glass substrates displayed the strongest multifractality indicating that such samples present space filling properties distributed over more spatial scales than the samples of BK7 and Si.

The XCL1-XCR1 axis has a potential role in the recruitment of immune cells to the site of inflammation. The present study aimed to examine the relation of XCL1 serum levels with Multiple sclerosis (MS) and HTLV-1-associated myelopathy (HAM), as chronic inflammatory diseases of the central nervous system (CNS). DNA was extracted to evaluate HTLV-1 proviral load (PVL) using real-time PCR. Serum levels of XCL1 was determined by using an ELISA assay. The serum level of XCL1 was significantly higher in patients with HAM than that of asymptomatic carriers (ACs) and healthy controls (HCs) (p 0.001 and p 0.0001, respectively) and was also higher in MS patients compared to HCs (p 0.0001). Moreover, the concentration of XCL1 serum level was significantly different between the ACs and HCs group (p 0.0001). In conclusion, increased expression of XCL1 might contribute to the migration of autoreactive T cells to the central nervous system and play a critical role in the development and pathogenesis of inflammatory neurological diseases including HAM and MS.

The purpose of this research is to explore the properties of CoSe nanostructured thin films on glass substrates prepared by a chemical solution deposition method. Special attention is given to study the effects of precursor concentrations (Cobalt(II) acetate, Ammonia and Sodium Selenosulphite), fixing the Co:Se concentration ratio, on the grainy structure and optical properties of the resulting thin films. The structural, chemical composition and morphological characteristics were investigated by X-ray diffraction (XRD), energy dispersive X-ray microanalysis (EDX) and scanning electron microscopy (SEM), respectively. The optical properties were determined by UV–visible spectroscopy determining the optical band gap energy (Eg). According to these results, the average particle diameter was decreased from 119 to 42 nm as the precursor salt concentration was decreased from 0.3 to 0.1 M, being the bigger nanoparticles more spherical. With the reduction of the particle size, a blue shift in the absorption peaks of the UV–visible spectra and an increment of their optical band gap energy (from 1.8 to 3.6 eV) occurred due to confinement effects.

Cystic echinococcosis (CE) is an important zoonotic parasitic disease worldwide. Application of species-specific antigen for serodiagnosis of human CE has not been utilized, so far. In this regard, AgB originated fromThe hydatid cyst fluid (HCF) ofOverall, 38 (84.4%) out of 45 confirmed human CE were positive by ELISA using AgB originated fromDue to the diversity of the cyst species in human population, application of AgB from prevalent species alone or in combination with other species is suggested.

Knowing the exact pressure of the process has a great impact on the validity of the results, product quality, energy efficiency, and in some processes, on the security of work with the system. Hence, the calibration of the barometers and the accuracy of the readings should be taken seriously. Choosing the appropriate time interval for re-calibration is done according to the extent and conditions of use, uncertainty, and the inaccuracy allowed in measurement, constructive suggestion, and some other things. Failure to pay attention to the importance of periodic calibration in vacuum gauges leads to some irreparable losses in the research project and the vacuum generator system. In this study, using McLeod's barometer, the deviation of capacitive and Pirani vacuum gauges is investigated at different time intervals in the middle vacuum range, and it is determined that the vacuum gauge faces a serious deviation from the actual calibrated amount for upper and lower ranges of middle vacuum in the same working pressure range over time.

The characterization of ion beam current density distribution and beam uniformity is crucial for improving broad-beam ion source technologies. The design of the broad ion beam extraction system directly affects these two parameters, therefore, depending on the application, the design and geometry of the source is changed. In this study, the effect of the presence or the absence of a neutralization process on the ion beam density was investigated. Also, the effect of the probe bias on the ion beam current measurement was evaluated. Eventually, using a flat probe, the ion beam profiles obtained from the extraction system of the ion source (Model RFIS 60, ACECR, Iran) were measured at energies from 300 eV to 1000 eV and compared in terms of current and uniformity of the ion beam in the absence of the neutralizer. In these experiments, screen and accelerator grids with different geometries (flat and convex grids) were used for comparison purposes. According to the obtained results, the flat grids generate a higher current density while the convex grids generate a more uniform beam. Therefore, each of these grid geometries can be suitable depending on the desired application.

The aim of this research is to fabricate Ag nanoparticle assemblies forming nanolayers with different thicknesses in order to evaluate their physical properties and their 3-D (three-dimensional) surface micromorphology. Such Ag nanolayers were deposited by physical vapor deposition methods under ion-beam irradiation in argon atmosphere at room temperature. X-ray diffraction (XRD) characterizations confirmed the formation of silver nanocrystals. Using surface field parameters, which were derived from atomic force microscopy (AFM) analysis, the surface morphology of the nanolayers were described according ISO 25178-2:2012. The height and slope distribution functions, together with the autocorrelation (ACF), the height–height correlation (HHCF) and the power spectral density (PSDF) functions were determined for the different analyzed samples using linear interpolation in the horizontal direction. All samples had a fractal character with a fractal dimension of 2.54 ± 0.01 independent of the film thickness.

Background: physical activities play an important role in increasing heart and blood vessels performance. The aim in this is determining the influence of 10 weeks aerobic exercise and 6 weeks non exercise on relaxation blood pressure of healthy non athletic girl students. Materials and Methods: In this semi experimental study 27 non athletic female students with 22/30± 1/70 were selected voluntary and attended the 10 weeks program, three sessions with 55 to 80% extra systole. After 10 weeks aerobic exercise, volunteers spent 6 weeks without exercise. Before starting the aerobic term, after non exercise term, after exercise term and also after non exercise term, relaxation blood pressure of the volunteers were measured by mercury Richter pizometer. Results: The results showed that there is a meaningful difference between volunteers relaxation systolic blood pressure in pre and post test and also in post test 1 and 2, but there is not any meaningful difference between volunteers relaxation systolic blood pressure in these tests. Conclusion: 10 week aerobic and immediately 6 week without exercise can be effective in relaxation blood pressure

Nanocomposite thin films made of partially oxidized Cu nanoparticles embedded into hydrogenated amorphous carbon, with different thicknesses and Cu/C ratio, were prepared by means of radio frequency plasma enhanced chemical vapor deposition and radio frequency sputtering using acetylene gas and copper target. The surface roughness was investigated using atomic force microscopy, revealing the fractal geometry of the Cu/carbon thin films at the nanoscale with fractal dimensions around 2.7. In addition, the electrical properties of these films and their dependence on the application of low magnetic fields were explored at room temperature. It was found that when the Cu nanoparticles are separated by gaps, the electrical conduction is governed by tunneling effects. In these conditions, the samples exhibit negative magnetoresistance values, displaying steps in the dependences on the magnetic field. These properties suggest the potential use of these films as magnetic sensors in spintronics.

Autocorrelation techniques are crucial tools for the study of the micromorphology of surfaces: They provide the description of anisotropic properties and the identification of repeated patterns on the surface, facilitating the comparison of samples. In the present investigation, some fundamental concepts of these techniques including the autocorrelation function and autocorrelation length have been reviewed and applied in the study of titanium nitride thin films by atomic force microscopy (AFM). The studied samples were grown on glass substrates by reactive magnetron sputtering at different substrate temperatures (from $ 25 {}^{\circ}{\rm C}$ to $ 400 {}^{\circ}{\rm C}$ , and their micromorphology was studied by AFM. The obtained AFM data were analyzed using MountainsMap Premium software obtaining the correlation function, the structure of isotropy and the spatial parameters according to ISO 25178 and EUR 15178N. These studies indicated that the substrate temperature during the deposition process is an important parameter to modify the micromorphology of sputtered TiN thin films and to find optimized surface properties. For instance, the autocorrelation length exhibited a maximum value for the sample prepared at a substrate temperature of $ 300 {}^{\circ}{\rm C}$ , and the sample obtained at $ 400 {}^{\circ}{\rm C}$ presented a maximum angle of the direction of the surface structure.

Thin films of Ag/Cu were deposited by reactive DC magnetron sputtering on (001)-oriented Si and glass substrates for various deposition times (4–24 min). These films were characterized by atomic force microscopy (AFM), and a power law scaling was performed on the obtained micrographs to investigate the self-affine nature of the sample morphology, which is indicative of a fractal structure. We applied the Higuchi’s algorithm to the AFM data to determine the fractal dimension of each sample, and the Hurst exponents were computed. The deposition time dependences of these parameters and the grain size distributions estimated from the UV–visible spectra using the Mie theory, allowed us to describe a particle formation mechanism during the deposition process, in which the length of continuous paths of conductive particles increases as the deposition time is increased. In agreement with this explanation, the electrical resistance decreased with the increment of the deposition time.

Background: The umbilical cord normally consists of two arteries and one vein. Single umbilical artery (SUA) is a condition in which the cord contains only one artery. SUA may be isolated or associated with congenital anomalies. This anatomic variation can be detected by ultrasound evaluation in approximately 0.5% of pregnancies. The incidence of adverse outcomes primarily depends on whether SUA is an isolated finding or associated with fetal abnormalities and aneuploidy. The aim of this study was to investigate fetal and maternal outcomes of isolated SUA. Methods: In this cohort study, 21 fetuses with isolated SUA, and 21 fetuses with normal three-vessel umbilical cord were included. All cases were examined by advanced fetal anomaly scan. In addition, cardiac, genitourinary, musculoskeletal, gastrointestinal, and neurologic anomalies were excluded. Two group were monitored during pregnancy, at delivery, and neonatal period. Perinatal and maternal outcomes were recorded. Results: Among 21 fetuses with isolated SUA, the left and right arteries were absent in 12 and 9 fetuses, respectively. Interestingly, the mean head circumference at birth was significantly lower in the isolated SUA group compared to the 3-vessel group (33.35 + 2.06 cm vs 35.21 + 1.47 cm, P = 0.002). However, there was no statistically significant difference between the two groups in birth weight and length, as well as incidence of polyhydramnios, oligohydramnios, intrauterine growth retardation, intrauterine fetal death, small for gestational age, preterm delivery, cesarean delivery due to fetal distress, and neonatal intensive care unit admission. Conclusions: In the absence of associated anomalies, the risk of incidence of adverse events does not appear to be increased significantly with isolated SUA. Therefore, supplementary assessment and invasive tests are not recommended in fetuses with isolated SUA, unless fetal abnormalities are detected in routine evaluations.

Residual stresses resulted from localized non-uniform heating and subsequent cooling during welding processes enact an important role in the formation of cracks and welding distortions and have severe effect on performance of welded joints. The present research performs a three dimensional transient thermo Elasto-plastic analysis using finite element technique to simulate welding process. Welding simulation procedure is developed using the parametric design language of commercial code ANSYS for single pass T and butt welded joints. The procedure verified with predicted residual stress field found in literature to confirm the accuracy of the method. The material of the weld metal, HAZ and the base metal are assumed to be the same. With regards to high temperature gradient in weld zone, temperature dependant thermal and mechanical properties have been incorporated in the simulation. Also in this work the technique of element birth and death was employed to simulate moving heat source and the weld filler variation with time. Temperature and residual stress fields were discussed.