Due to the fact that the velocity of air flow in the combustion chamber of scramjets is supersonic, so there is not enough time for proper mixing of fuel and air at these high speeds, and studying the process of mixing of fuel and air in this situation is one of the important issues for scramjet engine design. One of the most widely used methods of fuel Injection in supersonic flows of scramjet engine combustion chambers is the method of transverse Injection into supersonic air crossflow. Since the velocity of the passing air is very high in such streams, it is challenging to achieve a suitable mixture for combustion. In the present work, by solving the three-dimensional Reynolds-Averaged-Navier-Stokes equations with the k-ω sst turbulence model and the ideal gas state equation, the transverse Injection domain in the supersonic flow is numerically simulated and the effect of Injection diameter is investigated based on the mixing properties such as fuel penetration depth, mixing efficiency, effective mixing area ratio and stagnation pressure losses. After that, results of reactive flow are presented.

Background: The aim of radiation therapy is to deliver a precisely measured dose of irradiation to a defended tumor volume. Simulation has been used instances to document the configuration of the portal and target volume to be irradiated accurately. Unfortunately, there is non-Conventional simulation in most of cancer centers in Iran. There fore in this study, it was tried to estimate pelvic inlet from inrerspinous diameter (distance between two Ant. Sup. Iliac spine) of the aforementioned patients in Radiotherapy – Oncology Department in Imam Hossein hospital. Materials and methods: Interspious diameter on the surface kin (X) and pelvic inlet (Y) on simulation in the 44 men and 61 women were determined, coefficient (r) in men and women rm=0.8841 rw=0.8141 and linear regression analysis the following equation was obtained. Y=0.525X-0.339 R2=0.7815 for men Y=0.326 X+5.18 R2=0.6626 for women Conclusion: It was concluded that in both men and women, it is possible to estimate pelvic Inlet diameter from Interspinous diameter. But the coefficient of determination (Rsq) is lower in women than men.

In this study the effect of pipe diameter of the high pressure fuel Injection system (FIS) on the performance and emissions of an off-road internal combustion diesel engine has been studied. Numerical simulation of the fuel pipe shows that the Injection chamber pressure, rate of fuel Injection and fuel pipe pressure decrease with increasing the pipe diameter. In order to investigate the effect of fuel pipe diameter on exhaust emissions, an off road diesel engine has been tested according to an eight-mode steady-state test cycle based on the United Nations standard ECER96. Results show that an increase in the pipe diameter decreases the nitrogen oxides (NOx) emissions, but it increases the unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions.

Introduction: In different studies worldwide, gender ratios derived from ICSI (Assisted reproductive techniques) have been reported differently. Objective: Evaluation of neonatal gender in ICSI women referred to Mehr Infertility Research Center of Rasht. Materials and Methods: In this descriptive-analytical study, the cases of infertile women referred to Mehr Infertility Research Center in Rasht for ICSI were examined to determine the sex ratio of the neonates. Data were analyzed using SPSS 21 and descriptive and an alytical (Chi-square and independent t) tests. Results: The results showed that 52% of single-born neonates, 60% of multiple pregnancies (single sex) and 52. 5% of multiple pregnancy (two sexes) were male. Conclusion: The ratio of male in single and multiple pregnancies in ICSI was higher than female.

In this paper, fluid flow in Francis turbine draft tube is simulated with and without water Injection condition in unsteady state using actual and straight diffuser geometry of draft tube. Also a new method for selecting nozzle diameter for Injection is proposed. Simulation is carried out using Fluent software and k-ε and SST k-ω turbulence models in the straight and actual geometries of the draft tube, respectively. In two considered geometries, results of proposed method for selecting the nozzle diameter, which is based on the ratio of the total loss to the pressure recovery factor, have been compared with the method used in the previous researches, which was based on the total loss calculation. Inlet boundary conditions and validation are based on the experimental data. Results show that selecting nozzle diameter is depended on the geometry of the draft tube, and using the ratio of total loss to pressure recovery factor approach for selecting nozzle diameter will improve the size of selected nozzle diameter up to 33%, velocity fluctuations up to 16. 3% and pressure fluctuations amplitude up to 19% in draft tube.

Background and aim: According to the frequent tooth loss at molar sites and necessity to replace them, the purpose of this study was to evaluate the short term clinical and radiographic outcomes of fresh molar sockets immediately implanted, with tapered wide platform implants.Materials and Methods: 10 patients with the mean age of 46 were treated with the immediate implantation of 12 wide diameter and wide platform implants in the molar sites.Following the atraumatic extraction of molars and preservation of the interradicular septum, implantswere placed. Immediately after the insertion of healing abutment, implant primary stability was tested with the Periotest and the crestal bone level was estimated with the periapical long-cone radiographs.Four months later patients were recalled for final evaluations, the crestal bone loss was measured and the periotest values were judged with the Wilcoxon test.Results: All 12 implants were reported with no pain, infection and continuous radiographic lucency.The average PTV1 and PTV2 reported were -4.9±0.99 and -4.6±1.37 (-2 to -7).The difference between PTVs wasn' t statistically significant (P>0.05).The average crestal bone loss was 0.54±0.96.Conclusion: Successful results were achieved with wide diameter and wide platform implants with the appropriate case selection and surgical technique.

Background :Failed back surgery syndrome (FBSS) is a challenging chronic pain condition following spinal surgery, often resistant to conventional therapies. Caudal epidural Injection is a mainstay for managing FBSS, yet its effects on intracranial pressure (ICP), particularly in adults with post-surgical anatomical changes, remain poorly understood. Optic nerve sheath diameter (ONSD) measured by ultrasound offers a non-invasive surrogate marker for detecting alterations in ICP. Methods :This prospective single-center clinical trial enrolled 46 adult FBSS patients scheduled for therapeutic caudal epidural Injection at Imam Hussein Hospital, Tehran, Iran. Each participant received a standardized two-stage, 30 mL caudal epidural Injection. The ONSD and hemodynamic parameters [systolic, diastolic and mean arterial blood pressure (SBP), (DBP), (MAP), heart rate (HR)] were assessed at baseline, immediately, and then at 10, 20, and 40 minutes post-Injection. All measurements were performed by blinded, trained personnel using validated protocols. Results :Caudal epidural Injection produced a significant, transient increase in mean ONSD (baseline: 4.8 ± 0.49 mm; immediate post-Injection: 5.1 ± 0.50 mm; P < 0.001), which normalized within the observation period. No patient exhibited symptoms or clinical signs of raised ICP. While serial monitoring indicated statistically significant reductions in SBP, DBP, MAP, and HR at 40 minutes, all values remained within physiologically acceptable ranges. No major procedural complications or adverse neurological outcomes occurred. Conclusions :Standard-volume caudal epidural Injection in adults with FBSS causes a temporary, asymptomatic elevation in ONSD, reflecting a reversible change in ICP. The procedure was well tolerated, with minimal and clinically insignificant hemodynamic effects, supporting its safety and utility in this patient population.