Studies on Pitting Corrosion of Al-Cu-Li Alloys Part II: Breakdown Potential and Pit Initiation.

Prediction of the accumulated pitting corrosion damage in aluminum-lithium (Al-Li) is of great importance due to the wide application of these alloys in the aerospace industry. The Point Defect Model (PDM) is arguably one of the most well-developed techniques for evaluating the electrochemical behavior of passive metals. In this paper, the passivity breakdown and pitting corrosion performance of AA 2098-T851 was investigated using the PDM with the potentiodynamic polarization (PDP) technique in NaCl solutions at different scan rates, Cl- concentrations and pH. Both the PDM predictions and experiments reveal linear relationships between the critical breakdown potential (Ec) of the alloy and various independent variables, such as aCl- and pH. Optimization of the PDM of the near-normally distributed Ec as measured in at least 20 replicate experiments under each set of conditions, allowing for the estimation of some of the critical parameters on barrier layer generation and dissolution, such as the critical areal concentration of condensed cation vacancies (ξ) at the metal/barrier layer interface and the mean diffusivity of the cation vacancy in the barrier layer (D). With these values obtained-using PDM optimization-in one set of conditions, the Ec distribution can be predicted for any other set of conditions (combinations of aCl-, pH and T). The PDM predictions and experimental observations in this work are in close agreement

Studies on Pitting Corrosion of Al-Cu-Li Alloys Part III: Passivation Kinetics of AA2098-T851 Based on the Point Defect Model.

In this paper, the passivation kinetics of AA2098-T851 was investigated by a fundamental theoretical interpretation of experimental results based on the mixed potential model (MPM). The steady state passive layer formed on the AA2098-T851 in NaHCO3 solution in a CO2 atmosphere upon potentiostatic stepping in the anodic direction followed by stepping in the opposite direction was explored. Potentials were selected in a way that both anodic passive dissolution of the metal and hydrogen evolution reaction (HER) occur, thereby requiring the MPM for interpretation. Optimization of the MPM on the experimental electrochemical impedance spectroscopy (EIS) data measured after each potentiostatic step revealed the important role of the migration of Al interstitials in determining the kinetics of passive layer formation and dissolution. More importantly, it is shown that the inequalities of the kinetics of formation and dissolution of the passive layer as observed in opposite potential stepping directions lead to the irreversibility of the passivation process. Finally, by considering the Butler-Volmer (B-V) equation for the cathodic reaction (HER) in the MPM, and assuming the quantum mechanical tunneling of the charge carriers across the barrier layer of the passive film, it was shown that the HER was primarily controlled by the slow electrochemical discharge of protons at the barrier layer/solution (outer layer) interface

Petersen’s Hernia as a Complication of Bariatric Surgery: A Case Report

Background: Bowel obstruction due to Petersen hernia is a known but rare late complication of a R-Y surgery that can be a life threatening condition.  Delayed intervention may result in a high morbidity and even mortality. The clinical findings are not specific, In this context, imaging exams have an important part in the early detection and surgery of this condition. Cases Report: We describe the case of a 46-year old man presenting with acute abdominal pain and a history of gastric bypass five years previously. Abdominal Ultrasound did not reveal any significant findings. Indeed, through the use of multi slice computed tomography with IV and oral contrast , diagnosis of internal hernia was made and confirmed by laparotomy. Conclusion:Internal hernias are rare and difficult to diagnose, but they should be included in the differential diagnosis in intestinal obstruction cases and a history of abdominal surgery to reduce the high morbidity and mortality rates; surgical intervention shouldn’t be delayed

Single-dose Intravitreal Bevacizumab after Complete Panretinal Photocoagulation in Proliferative Diabetic Retinopathy: an Effective Adjunctive Treatment

Patients with proliferative diabetic retinopathy (PDR) who are refractory to complete panretinal photocoagulation (PRP) have a high risk of severe vision loss. The aim of this study was to evaluate the effectiveness of single-dose intravitreal bevacizumab (IVB) after complete PRP in patients with refractory PDR. Patients with retinal neovascularization (NV) secondary to diabetes mellitus and refractory to complete PRP were enrolled in this study. All patients received a single dose of 1.25 mg IVB at 3 months after completing the PRP. Patients underwent complete ophthalmic evaluation and fluorescein angiography (FA) at baseline and 1 month after injection. The main outcome measure was a reduction in the areas of leakage (mm2) on FA. All patients were evaluated at baseline and on every visit at 1 day, 1 week, and 1 month after the injection. A total of 21 consecutive patients (32 eyes) with PDR completed this study. Thirteen (61.9%) patients were female. The mean ± standard deviation (SD) age was 64.1 ± 5.6 years. Complete and partial response of angiographic leakage of NV was noted in 7 (21.9%) and 18 (56.2%) of 32 eyes after a single IVB injection, respectively. No satisfactory response of retinal NV was observed in 7 eyes (21.9%) at 1 month after the injection. There was a significant difference in age between response groups (partial and complete; 61.9 ± 4.4 years) versus the no-satisfactory response group (67.7 ± 5.9 years) (P = 0.007). No significant ocular or systemic adverse events were observed. A single-dose of IVB could be associated with a satisfactory response of retinal NV, secondary to PDR, in patients who are refractory to complete PRP.Â

An analysis of underlying factors for implementing privatization in Iranian sport

The purpose of this research was to analyze the underlying factors of privatization implementation in Iran's sport, which was developed by developmental approach. Statistical population of this research was consisted of all managers and experts involved in sports privatization in the country. Regarding that this is a qualitative research, a total of 20 people were selected using the snowball purposeful sampling technique as a statistical sample. The data collection tool was interview. Interviews continued until the theoretical saturation stage was fulfilled. The data obtained from interviews were analyzed in three stages of open, axial and selective coding. The results of the research identified 41 concepts and 5 categories including factors related to financial market, management factors, media factors, cultural factors and legal factors that provide the platform for implementation of privatization in the sport of the country. According to the results of this research, privatization in Iran's sport has been affected by various conditions, it is suggested that sport authorities are encouraged to provide a condition in which people can be trained in order to gain specialty to enter in various areas such as advertising private sector and proper culture creation in press and TV and paying attention to philosophy of sport and culture creation among the people

AN IMPROVEMENT TO THE ANTICORROSIVE PROPERTIES OF EPOXY POWDER COATING BY ZINC PHOSPHATE AND ZINC ALUMINUM PHOSPHATE PIGMENTS

Epoxy powder coatings containing zinc aluminum phosphate (ZAP) and zinc phosphate (ZP), which are the 2nd and 1st generation of phosphate-based pigments respectively, were applied to the surface of mild steel sheets. The anticorrosive performances of the coated samples were studied using electrochemical impedance spectroscopy (EIS). Cathodic disbonding resistance and the adhesion performance of the two coating systems were measured by cathodic delamination and pull-off test respectively. The charge transfer resistance and double layer capacitance obtained from EIS revealed the greater anticorrosive performance of the coating modified by zinc aluminum phosphate compared to the one treated with zinc phosphate. While an electrolyte diffuses in the organic coating, phosphate pigments dissolve and make a passive layer on the surface of mild steel. Due to the more solubility of ZAP in comparison with ZP, the cathodic desbonding resistance and adhesion of the epoxy powder coating containing ZAP were greater than those of ZP-loaded powder coating. The results show that the anticorrosive performance of the epoxy powder coating containing ZAP is better than that of the epoxy powder coating modified with ZP

Assessment of the belief and attitudes of Iranian healthcare personnel’s toward the influenza infection and influenza vaccination

Introduction: influenza is one of the main public health problems and Health Care Personnel's is one of the at-risk groups for this infection. So regarding this point, the goal of this research was to identify the beliefs and attitudes of the HCPs (Health Care Personnel) about influenza and the influenza vaccine. Methods: This cross-sectional study was planned in a general hospital in Tehran; Iran from January to June 2016.A total of 418 questionnaires was distributed among the HCPs. The entire data set was analyzed using the SPSS. We used the Chi2 test, linear regression and one-way ANOVA for data analysis. P-values less than 0.05 were considered as statistically significant. Results: The influenza vaccination coverage was 57.7%; the highest vaccine rate belonged to the allied health professionals (68.2%). Two main causes for avoiding the influenza vaccination were; the “fear of vaccine adverse effects” and the “uncertainty about the vaccine effectiveness”. The linear regression analysis identified that the physicians had the highest belief score, followed by the nurses and the allied health professionals (p <0.001).  Conclusions: Educational planning on influenza and influenza vaccination is necessary to improve the vaccination coverage and to reduce the influenza mortality and morbidity in susceptible patient

Strategic planning, components and evolution in zoonotic diseases frameworks: one health approach and public health ethics

Zoonotic diseases are seen as a major public health concern. Routes of the rapid transmission of zoonotic diseases and the economic damage they cause to communities are all reasons why health institutions and systems need to pay more attention to these diseases. Strategic planning is one of the important tasks of policymakers in every organization and system. It is a very reliable and useful tool for leading all kinds of organizations, including health organizations. Countries with clear policy plans have succeeded in controlling and reducing zoonotic diseases. Such countries used appropriate strategic planning and pursued annual goals to control and prevent diseases. Three important steps (strategy development, strategy implementation and strategy evaluation) should be considered in developing a strategic planning for controlling and prevention of zoonotic diseases. Health systems need to develop strategic planning in order to upgrade their capabilities in combating zoonotic diseases. These programs must be flexible, in line with the one health approach, based on the current needs, and aligned with the new challenges faced with health systems. The strategic planning is directly related to national and international policies, organizational goals and missions, dynamism, degree of complexity, and organizational structure of each country's health system