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In the present study, the deposition of silicon nitride (Si3N4) coating on Inconel 738 through plasma spray has been investigated. For producing the Si3N4 coating, different times (6, 8 and 10 s), different distances of the plasma spray torch from the substrate (30, 35 and 40 mm) and different currents for plasma spraying (3000, 3250 and 3500 A) were employed. For the characterisation of the coatings, SEM (thickness), XRD, micro-hardness and adhesion of the samples were measured. The coatings' surface morphology was investigated through SEM. Based on the experimental results, by using a spraying time of 10 s, a distance of the torch of 40 mm and a current of 3500 A, high microhardness and adhesion of the coatings are obtained. On the other hand, the thickness of the coating increased by reducing the distance and increasing spray time and current. [ABSTRACT FROM AUTHOR]

Background: Cytomegalovirus (CMV) infection is the most common complications following kidney transplantation. Natural killer (NK) cells demonstrated critical anti-viral role in controlling and elimination of CMV after transplantation. Interleukin-15 (IL-15) is a pleiotropic cytokine that promotes the activity of NK cells and strengthens the acquired immune system. Also, IP10 (CXCL10) is a chemotactic factor which regulates NK cell recruitment and antiviral immune response. We aimed to determine the correlation between the serum levels of IL-15 and IP-10 cytokines with CMV infection, CMV viral load, and cyclosporine as a major immunosuppressive treatment after transplantation. Methods: Fifty-eight kidney transplant recipient patients without evidence of CMV virus disease before transplantation surgery were included in the study. From the day of transplant surgery, the patients were evaluated based on the presence of CMV Ag pp65, CMV viral load, serum levels of IL-15 & IP-10, Cyclosporine levels (C0 & C2), Glomerular Filtration Rate (GFR), and hematological & biochemical Index, up to 75 days. Results: Comparison analysis of serum levels of IL-15 and IP-10 showed no significant association with CMV infection in kidney transplant recipients. In addition, CMV viral load and cyclosporine levels at C0 and C2 did not affect patients' IL-15 and IP-10 levels. Conclusions: The levels of IP-10 and IL-15 cytokines are not affected with CMV infection, even if a viral infection occurs in the early days after transplantation or long afterwards. In addition, taking the different levels of cyclosporine did not affect the cytokines levels. Other mechanisms may play a role in maintaining the levels of these cytokines. [ABSTRACT FROM AUTHOR]

Diabetic foot ulcer is one of the most common causes of amputation and imposes high social costs. The present study was conducted to evaluate the effect of oral arnebia euchroma extract on wounds in diabetic rats and was compared with oral and topical forms of ANGIPARS.Thirty diabetic male Wistar rats were categorized into different groups with similar wounds, and were treated with oral and topical forms of arnebia euchroma extract and ANGIPARS ointment and capsules, and were compared with each other and the control group. The clinical and statistical results indicate the superior effect of oral and topical forms of arnebia euchroma extract in comparison with oral and topical forms of ANGIPARS.The epithelial thickness(F (4.25) = 4189.10, p<0.01) and complete healing time(F (4.25) = 18.01, p<0.01), were respectively calculated. It is recommended that a human study be conducted to determine the level of blood glucose and its effect on TNFa and myeloperoxidase as the factors affecting tissue repair. [ABSTRACT FROM AUTHOR]

Summary: Recurrent vulvovaginal candidiasis (RVVC) is a common opportunistic, mucosal fungal infection, predominantly caused by the fungus Candida albicans. Mannose‐binding lectin (MBL) is an acute‐phase protein that plays a key role in the innate immunity defence against infectious disease. This study was conducted to evaluate the relationship between the MBL serum level and the relative expression of MBLmRNA in RVVC using real‐time PCR for the first time. The case‐control study included 40 female participants suffering from RVVC and 40 healthy individuals. The MBL serum level was measured using a commercial ELISA kit. The relative mRNA expression of the MBL gene was quantified using real‐time PCR. Data analysis was carried out by spss software. The MBL concentration was significantly higher in the participants suffering from RVVC compared to the control group (0.330 ng/mL vs 0.253 ng/mL). The prognostic value (P < .001) for RVVC diagnosis has been calculated. Quantitative RT‐PCR results from 35 samples showed a low to significant values for mRNA levels corresponding to MBL gene expression (1‐352 folds) (P < .001). The results of this study suggest that MBL plays a main role in the innate immunity and it is also affected by environmental factors and other genetic variations. Therefore, the MBL gene expression profile does not reflect precise phenotypic levels in the serum. [ABSTRACT FROM AUTHOR]

In the present work, an attempt is made to study the predominant factors of ball burnishing namely, burnishing speed, burnishing feed, burnishing force, and pass number on the surface roughness, surface hardness, and out-of-roundness error of hard-turned AISI 4340 rods. Response surface methodology was used to correlate the empirical relationship between the process factors and responses. Also, the minimum surface roughness, out-of-roundness error, as well as the maximum hardness were taken into consideration for finding the optimal parameter setting. Analysis of variances was also performed to check the adequacy of the developed models. Results indicated that the most influential parameters for the surface roughness and roundness error is the burnishing feed. Also, for surface hardness, it was found that the pass number had the greatest influence. It was further seen that a burnishing speed of 150 r/min, burnishing feed of 0.16 mm/rev, burnishing force of 24.5 N, and pass number 4 yields the desirable burnishing quality characteristics. The obtained results were then validated through performing morphological study and microstructural observation of the burnished surface. [ABSTRACT FROM AUTHOR]

In present study, an attempt based on a hybrid approach was made to find optimal tube drawing parameters combination (i.e., die semi-angle, friction coefficient, tube entrance velocity, deformation length, and primary tube diameter) achieving minimum forming force, minimum dimensional error along with maximum thickness in longitudinal and circumferential directions. In order to form a design matrix, Taguchi L27 design was used and required data were derived from finite element model of the process. Adaptive neuro-fuzzy inference system (ANFIS) was then used to correlate process inputs to and responses aforementioned response outputs. Prediction accuracy of created ANFIS models was further checked by FE simulation and experimental testing data. Finally, the models were integrated to form objective function that was optimized by teaching–learning-based optimization (TLBO) algorithm. To check the adequacy of optimization, a finite element run and an experiment were carried out by obtained optimal parameter setting and the results were compared. The findings indicated that that the proposed methodology, that is, FEA-ANFIS-TLBO has superiority in identifying the optimal results. [ABSTRACT FROM AUTHOR]

Metallic bipolar plates are the most important part of proton exchange membrane fuel cell (PEMFC). In order to manufacturing of these plates, various method such as Hydroforming, electromagnet forming and stamping have been used. In this study rubber pad forming process was selected in order to forming metallic bipolar plates with stainless steel 316. At first effect of punch load, thickness and hardness of rubber on channel depth (before fracture) were investigated in order to determinate the maximum channel depth before fracture. After that, a novel method was developed by machining the rubber pad in order to prevent from fracture and increase in channel depth. According to the result, increase in hardness of rubber lead to decrease in channel depth and increase in applied force and thickness of rubber lead to increase in channel depth. Maximum filling percentage (before fracture) in rubber pad forming process was 76% achieved by Shore A 40 rubber pad with thickness of 30 mm and maximum thinning percentage before fracture is about 30%. Using new method was successful to prevent from fracture and formability has been increased by machining the rubber pad. As a result, the filling percentage for bipolar plate increased to 88%. [ABSTRACT FROM AUTHOR]