Background: Several surgical reconstructive procedures are introduced to repair a hypospadiasis while post-operative complications have still remained high. Poor tissue handling, anastomotic site ischemia, tension on the anastomotic line, and distal obstruction are suggested as the main risk factors contributing to post-operative complications. This article is the introduction of a simple technical Modification to perform a uniform straight tension free urethroplasty that is supposed to decrease post hypospadias repair complications. Methods: We used a 6F silicon Foley catheter and covered it by a part of 10 F Nelaton catheter at the most distal part of the Foley. To facilitate the covering and uncovering process, weincised the Nelaton catheter in one side through the whole length. We performed a two-Layer closure urethroplasty over our double Layer stent and finally uncovered the Foley catheter, which remains in the bladder as a trans-urethral stent and also for further bladder drainage. ResultsandConclusions: In our innovative method of urethral stenting, wehave suggested to replace the transurethral stent with a tension free lower size catheter easily and safely at the end of procedure, which helps decrease suture line tension and is supposed to improve the local circulation.

In this study, the Surface of polyethersulfone nanofiltration membranes was modified by a nanocomposite Layer containing POSS nanoparticles. The effect of the Surface Modification, on the structure, separation, and other properties of the membranes was checked. Pristine membranes were prepared by the phase inversion method. The surface of the membrane was modified by the dip coating method. Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) analysis, and scanning electron microscopy (SEM), were applied in membrane characterization. Moreover, Pure water flux, salt rejection, membrane porosity, mean pore size of the membrane, water content, and water contact angle were applied to evaluate membranes. The FTIR results proved the creation of a nanocomposite Layer with the POSS nanoparticles on the surface of the virginal membrane. SEM images confirmed that a new Layer was uniformly present on the surface of the modified membranes. The amount of water content for double-Layer membranes had an increasing trend compared to pristine membranes, also, the results of the contact angle showed a decrease in the surface roughness for the modified membranes then with increasing concentration of glycidyl-pass nanoparticles, that is a hydrophobic substance, went through a decreasing trend. By increasing Acrylic Acid, the porosity was enhanced but after utilizing glycidyl-pass nanoparticles, it showed a decreasing trend. Also, the pure water flux showed a decreasing trend. The rate of return had an increasing trend for the membranes. The addition of glycidyl-pass nanoparticles up to 0.1% by weight resulted in the yield of 59.74% Na2SO4 and 64% for CrSO4.

Poly-caprolactone (PCL) has been widely used as scaffolding material for tissue engineering applications due to its good biocompatibility and suitable mechanical properties. However, lack of suitable surface functional groups is one of limitations related to cell attachment of this material. In this work, gelatin was coated on the surface of PCL films using physical entrapment process. Polymeric solution (acetic acid- 5%wt PCL) was cast in a glassy mold then mold remained under vacuum for 24 hours in order to evaporate acetic acid and create of film. The composition of water- acetone system (water is dissolving gelatin and acetone is swelling the surface of the film) is the critical point in performance of the physical entrapment process; so different composition was made and gelatin was dissolved in them. PCL film was immersed in each gelatin solutions for different times. In order to improve the attachment of the gelatin on the surface of PCL, chemical crosslinking was done by glutaraldehyde solution. Quality of coating Layer was evaluated by using Attenuated Total Reflection–Fourier Transform Infrared spectroscopy (ATR-FTIR). Thickness of PCL film and gelatin coating was estimated by Scanning electron microscopy (SEM). Contact angle measurement (Sessile drop) was done to analysis surface wettability before and after coating process. Mechanical properties also measured by strip tensile test. Results showed that amount of entrapped gelatin increased by increase of acetone in gelatin solvent. Mechanical strength increased to two fold also young modulus and elongation improved about 50% due to surface Modification. In addition Surface Modification improved wettability.

Study of electron injection materials is one of the most important steps in obtaining high efficient and low driving voltage in organic light – emitting diodes (OLEDs). In this article, we simulated OLED devices with structure of ITO/PEDOT: PSS/PH-PPV/EIL/Al in Atlas Silvaco in which, NaSt, Al2O3 and TiO2 are used as electron injection Layer (EIL). The OLED with Al2O3 exhibited higher current density, higher luminance (13550 cd/m2), lower driving voltage (2. 3V) and lower operating voltage (4. 05V) compared to the two other structures. The reason is greater electric field (about 2. 4 times greater than that of two other structures) due to much more difference between work function of the device with Al2O3 and electron affinity of PH-PPV, causing improvement of charge carrier injection. Furthermore, recombination almost occurs in the middle of the light emission Layer. However, the OLED that employs TiO2 as electron injection Layer, showed the highest external efficiency due to increase in radiation recombination rate in comparison with other recombination mechanisms in the light emission Layer.

In this work, the surfaces of spherical mesoporous silica were modified with potassium copper hexacyanoferrate ([KCu(Fe(CN)6)]), then employed as a new ion exchanger nanocomposite to adsorb cesium ion from an aqueous solution. The materials have been characterized by Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), N2 adsorption-desorption isotherms (BET), and FTIR spectroscopy. The effect of contact time, pH, and initial concentration of the solution on adsorption efficiency were studied. Langmuir, Freundlich, and Tempkin's isotherm models analyzed the equilibrium concentration data. The data was in good agreement with the Langmuir model showing cesium adsorption process was a monoLayer. The pseudo-second-order model was adequate to describe cesium uptake kinetic behavior, and the maximum equilibrium adsorption capacity for the nanocomposite was 46/4 (mg/g).

Background: Bleeding and pseudoaneurysm formation are the dangerous complications of the Bentall operation. We made a simple Modification to the proximal anastomosis in the Bentall operation to reduce postoperative bleeding and false aneurysm incidence. This article presents a review of the early results. Methods: Totally, 171 consecutive patients (126 men and 45 women) underwent aortic root replacement between September 2014 and April 2020: as an elective operation in 130 patients (76. 02%) and as an emergent or urgent operation in 41 (23. 98%). No exclusion criteria were applied. All the Bentall operations during the study period were performed via the same surgical technique. Statistical analysis was conducted with the SPSS 11. 0 statistical software package (SPSS, Chicago, IL, USA). Continuous variables were expressed as the mean ±,the standard deviation and compared using the unpaired 2-tailed t test, and categorical variables were analyzed using the χ, 2 test or the Fisher exact test, where appropriate. Results: The mean duration of cardiopulmonary bypass was 88. 30 minutes, and the mean duration of aortic clamping was 53. 17 minutes. Reoperation was required due to postoperative bleeding in 14 cases (8. 19%). The early mortality rate was 8. 77%, and the incidence of complications was 15. 19%. Conclusions: Our simple Modification, which was the addition of a protection Layer, to the standard technique of the Bentall operation did not significantly increase the duration of cardiopulmonary bypass, and it seemed to have caused a significant decrease in bleeding after surgery and the need for reoperation.

Hypothesis: The surface Modification of poly(vinylchloride)-based heterogeneous cation exchange membranes was carried out using chitosanco-polyaniline/graphene oxide nanocomposite Layer for the application in electrodialysis process. Methods: The PANI/GO nanocomposites were prepared by in situ chemical oxidative polymerization of aniline in the presence of graphene oxide nanoplates. Fouriertransform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), water content, flux and permeability, areal ionic resistance, water softening ability and fouling measurements were used to characterize the membrane. Findings: The FTIR analysis results and SEM images demonstrated successful formation of polyaniline on the graphene oxide nanoplates. The scanning electron microscope images of membranes also exhibited a uniform Layer of chitosan-co-PANI/graphene oxide nanoplates on the membrane surface. The water content of modified membranes was higher than that of pristine membrane. The sodium flux and sodium permeability were improved about 20% by 0. 1 %wt PANI/graphene oxide nanocomposite. The areal ionic resistance of modified membranes also showed a decreasing trend by utilizing composite nanoplates in the membrane matrix. The prepared membranes showed good ability for Ca and Mg removal from water. The removal efficiency of Ca and Mg by membrane containing 0. 5 %wt PANI/graphene oxide composite nanoplates was, respectively, 61 and 79% during 15 min. Moreover, the pollutant and foulant formed on the membrane surface were totally removed by sonication technique. The modified membranes showed suitable electrochemical characteristics compared to membranes reported by other researchers and made by industries.

Aim: The aim of this study was to compare the effects of Ethylen glycol tetra acetic acid (EGTA) and EDTA for their smear Layer removal capability using scanning electron microscopy technique.Material and Methods: A group of 28 single rooted teeth were instrumented to size 60 master file. Four teeth were also kept as control while the remaining teeth were divided into two groups. Group A: in which 12teeth were irrigated with 10 ml of 17% EGTA for 2 minutes? Group B: consisted of 12teeth irrigated with 10 ml of 17% EDTA for 2 minutes. Both groups were then irrigated with 10 ml of 5% Naocl. the control group were just irrigated with 10 ml of 5 % Naocl. All teeth in then the control group were only irrigated with 10 ml of 5% Nacl. Specimeus were then sectioned longitudinally. A scanning electrone microscope was wsed to in vetig ate the intenal surfaces of the canal.Results: EGTA chelated dentin surface more conservatively than EDTA without causing erosion.Conclusion: It seems that EGTA can be used safely to remove smear Layer from the canal surfaces.

Modification of MnFe2O4@SiO2 core-shell nanoparticles with (3-aminopropyl) triethoxysilane (APTES) was investigated. The magnetite MnFe2O4 nanoparticles with an average size of ~33 nm were synthesized through a simple co-precipitation method followed by coating with silica shell using tetraethoxysilane (TEOS); that has resulted in a high density of hydroxyl groups loaded on nanoparticles. The prepared MnFe2O4@SiO2 nanoparticles were further functionalized with APTES via silanization reaction. For having suitable surface coverage of APTES, controlled hydrodynamic size of nanoparticles with a high density of amine groups on the outer surface, the APTES silanization reaction was investigated under different reaction temperatures and reaction times. Based on dynamic light scattering (DLS) and zeta potential results, the best conditions for the formation of APTES-functionalized MnFe2O4@SiO2 nanoparticles were defined at a reaction temperature of 70 °C and the reaction time of 90 min. The effectiveness of our surface Modification was established by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Fourier transforms infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). The prepared magnetite nanostructure can be utilized as precursors for synthesizing multiLayered core-shell nanocomposite particles for numerous applications such as medical diagnostics, drug, and enzyme immobilization, as well as molecular and cell separation.

Thin-Layer approximate engineering methods are used for calculation of in viscid hypersonic flows over blunt-nosed bodies. In these methods, the pressure is obtained using Maslen's pressure relation and the normal velocity component is calculated using an approximate relation which is not accurate enough in the leeward region. In this paper, a new relation for calculation of normal velocity has been derived from the continuity equation using thin shock Layer assumptions. It has been shown that the present relation has critically improved the profiles of velocity in the leeward region. Results are presented for a cone at angle of attack and are compared with finite difference solutions of Euler equations. Since the method is fast, it can be used for preliminary design or parametric study of hypersonic vehicles.