Comparison of oral prednisolone pulse therapy with intravenous methylprednisolone pulse therapy in severe alopecia areata

Objective: To compare the efficacy of oral prednisolone pulse therapy in comparison to the intravenous methylprednisolone pulse therapy in treatment of severe alopecia areata. Patients and methods: In this interventional study, all patients with alopecia areata having at least 30% involvement of scalp or more than 10 patches of alopecia in scalp and body, registered during 2006-2009 in dermatologic department of 5-Azar hospital, Gorgan, Northeast of Iran were included. Forty patients with severe alopecia areata were enrolled and divided into 2 groups. Group A was treated with 200 mg oral prednisolone in one dose, every week for 3 months and group B were treated with 500 mg intravenous methylprednisolone on 3 continuous days each month for 6 months. Results: Recovery rate after 1, 3, 6 and 12th months after treatment was significantly higher in group B compared to group A. Side effects included: acne (5 in group A and 7 in group B), heartburn (4 in group A and 5 in B), striae (4 in group A and 6 in group B) and were more seen in group B but it was not significant statistically. The recovery and rate was not significantly different between two sexes. Conclusion: In this study, 500 mg intravenous methylprednisolone in 3 continuous days each month for 6 months showed a better recovery rate in severe alopecia areata. Patients must be warned about the side effects and outcomes

A Conceptual Framework for Analysis of System Safety Interoperability of United States Navy\u27s Combat Systems

Today\u27s political and military reality requires the optimal use of our legacy systems. The objective is to maximize the effectiveness of our operations by efficient allocation, placement and the use of our forces and war-fighting systems. The synergism drawn from the capabilities of the legacy complex systems enables today\u27s war-fighting needs to be met without substantial increase in cost or resources. This synergism can be realized by the effective integration and interoperation of legacy systems into a larger, more complex system of systems. However, the independently developed legacy systems in this new tactical environment often have different data types, languages, data modeling, operating systems, etc. These differences are impediments to the requirement for interoperability, and can create an environment of confusion, misinformation and certainly un-interoperability, hence hinder the safe interoperation of the metasystem and potentially increase the risk for mishaps. Safe interoperability capability assures that the mission objectives are achieved not only effectively but also safely. The System Safety Interoperability Framework (SSIF) introduced in this dissertation provides the framework for the engineering community to evaluate, from system safety perspective, the interoperability issues between multiple complex systems in the U.S. Navy\u27s system of systems context. SSIF characterization attributes are System of Systems (SoS) tactical environment, SoS Engineering, SoS Safety Engineering, and Safety Critical Data. SSIF is applied to AEGIS Ballistic Missile Defense 3.0 Program to explore and analyze the safety interoperability issues in the overall system, by which the SSIF is further validated as an effective approach in analyzing the safe interoperability capability in Navy\u27s combat systems

The Role of Salt in the Pathogenesis of Fructose-Induced Hypertension

Metabolic syndrome, as manifested by visceral obesity, hypertension, insulin resistance, and dyslipidemia, is reaching epidemic proportions in the Western World, specifically the United States. Epidemiologic studies suggest that the increased prevalence of metabolic syndrome directly correlates with an increase in the consumption of fructose, mainly in the form of high-fructose corn syrup. This inexpensive alternative to traditional sugar has been increasingly utilized by the food industry as a sweetener since the 1960s. While augmented caloric intake and sedentary lifestyles play important roles in the increasing prevalence of obesity, the pathogenesis of hypertension in metabolic syndrome remains controversial. One intriguing observation points to the role of salt in fructose-induced hypertension. Recent studies in rodents demonstrate that increased dietary fructose intake stimulates salt absorption in the small intestine and kidney tubules, resulting in a state of salt overload, thus setting in motion a cascade of events that will lead to hypertension. These studies point to a novel interaction between the fructose-absorbing transporter, Glut5, and the salt transporters, NHE3 and PAT1, in the intestine and kidney proximal tubule. This paper will focus on synergistic roles of fructose and salt in the pathogenesis of hypertension resulting from salt overload

Appropriateness of referrals for single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) in a developing community: A comparison between 2005 and 2009 versions of ACCF/ASNC appropriateness criteria

Appropriateness of referrals for myocardial perfusion imaging (MPI) in developing countries has not been extensively studied. Our study was conducted to describe the ordering practices of physicians and appropriateness of MPI referrals in Iran. We prospectively applied 2005 and 2009 versions of the Appropriateness Use Criteria published by the American College of Cardiology Foundation (ACCF) and the American Society of Nuclear Cardiology (ASNC) to 291 consecutive patients (age 55.3 ± 10.3 years) who underwent SPECT-MPI. For this purpose, we convened a panel, consisting of two academic cardiologists, one academic clinician in internal medicine, and one academic clinician in nuclear medicine. The panelists were invited for a face-to-face meeting to judge appropriateness of SPECT-MPI and independently assign a specific indication (scenario), whenever possible, for each case in accordance with ACCF/ASNC appropriateness scenarios. Based on the 2005 ACCF/ASNC criteria, SPECT-MPI studies were judged appropriate for 211 (72.5%), uncertain for 36 (12.4%), inappropriate for 32 (11.0%), and unclassifiable for 12 (4.1%) referrals. The same figures based on the 2009 version were 219 (75.3%), 15 (5.2%), 49 (16.8%), and 8 (2.7%) patients, respectively. Overall agreement between the 2005 and 2009 versions was good (κ 0.63). Lack of chest pain and age below 60 years were significant indicators increasing the likelihood of inappropriate referrals by 2.9-3.4 fold. Absence of diabetes mellitus and hypertension, a normal lipid profile, lack of a past history of myocardial infarction or cardiovascular interventions (CABGs or PCI), as well as lack of application and exercise ECG stress test as the gate keeper (keeping abnormal ETT or inability of the patient to perform exercise as the appropriate indication for SPECT-MPI referral) were significant indicators, decreasing the odds of appropriate referrals. Generally a higher percentage of referrals with inappropriate indications had normal MPI. Our study provides an evidence for the fact that SPECT-MPI ordering practices in our developing community largely parallel the ACCF/ASNC recommendations. The implementation of appropriateness criteria is feasible in clinical settings and might provide an alternative to utilization management. © 2011 American Society of Nuclear Cardiology

Numerical comparison on the efficiency of conventional and hybrid buckling-restrained braces for seismic protection of short-to-mid-rise steel buildings

Buckling-restrained brace (BRB) is a specific kind of bracing system which has an acceptable energy dissipation behavior in a way that would not be buckled in compression forces. However, considerable residual deformations are noticed in strong ground motions as a result of the low post-yield stiffness of the BRBs. The seismic performance of a modern lateral load resisting system, which is called the hybrid BRB, and its conventional counterpart are assessed and compared in this paper. Multiple plates with different stress–strain behavior are used in the core of this new innovative system, and this is its difference with the existent BRBs. Nonlinear static and incremental dynamic analyses are carried out for three building frames with different structural heights, which use conventional and hybrid BRB systems. To carry out response history analyses, the FEMA P695 far-field earthquake record set was adopted in different hazard levels. The hybrid BRBs are shown to have superior seismic performance in comparison with the conventional systems based on the response modification factor and the damage measures including residual displacements and inter-story drift ratios

Optimal piston crevice study in a rapid compression machine

Multi-dimensional effects such as vortex generation and heat losses from the gas to the wall of the reactor chamber have been an issue to obtaining a reliable RCM data. This vortex initiates a flow in the relatively cold boundary layer, which may penetrate the core gas. This resulting non-uniformity of the core region could cause serious discrepancies and give unreliable experimental data. To achieve a homogenous temperature field, an optimised piston crevice was designed using CFD modelling (Ansys fluent). A 2-Dimensional computational moving mesh is assuming an axisymmetric symmetry. The model adopted for this calculation is the laminar flow model and the fluid used was nitrogen. To get the appropriate crevice volume suitable for the present design, an optimisation of the five different crevice volume was modelled which resulted to about 2-10% of the entire chamber volume. The use of creviced piston has shown to reduce the final compressed gas temperature and pressure in the reactor chamber. All the crevice volumes between 2-10% of the chamber volume adequately contained the roll up vortexes, but the crevice volume of 282 mm 3 was chosen to be the best in addition to minimising the end gas pressure and temperature drop. The final pressure trace from experiment shows a reasonable agreement with the CFD model at compression and post compression stage

An investigation into carbon deposition growth in jet engine injector feed arm due to fuel thermal degradation.

Investigation of tube fouling was carried out employing the heated nozzle module of Aviation Fuel Thermal Stability Test Unit (AFTSTU). This includes straight, thick-walled stainless steel tube, exposed to a constant heat flux provided by a Radio Frequency (RF) heating unit that is coiled around the tube. In this situation, deposits are allowed to form on the inner surface of the tube. Due to the considerably lower thermal conductivity of the deposit compared to the stainless steel, temperature at the tube external wall increases with time. This was recorded by the application of three pairs of thermocouple situated at different axial locations along the tube. Each pair of thermocouple monitored the data from two different radial positions. The fuel temperature at the tube exit was recorded by the use of another thermocouple. The recorded results for each thermocouple indicate that three distinct stages can be observed as function of time. The first stage represents a temperature invariant zone, known as induction period, followed by a remarkable temperature rise. The third stage represents a level off zone. Experiments were carried out for two different baselines fuels each experiment consists of four stages. In each baseline test, four different thermal powers were supplied by RF heater. Consequently, four initial tube wall temperatures were set. Then surface deposition was investigated during four different exposure time. The second baseline test is different from the first test in that the fuel inlet was kept at higher temperature. In order to imitate the temperature rise across the heated tube, a two dimensional, axis symmetric, time dependent Computational Fluid Dynamic (CFD) model was developed. In this model dynamic mesh technique was employed to predict the temperature rise in a changing boundary. This technique was also used to imitate the surface deposition in Near Isothermal Flowing Tube Reactor (NIFTR) where the tube is subject to the constant wall temperature. The experimental results of the NIFTR for code validation were taken from the literature. A number of preliminary investigations were performed prior to the CFD modelling on the chemistry of autoxidation, the process which is responsible for the formation of species precursor. Pseudo-detailed mechanism of liquid phase autoxidation which is widely used in most of the investigations was used for in this thesis. In order to develop an integrator code for the investigation of rate equations, two different approaches were applied. Firstly an integration based on the Taylor series was applied. In spite of the applicability of this method for the reduced chemical schemes (3-4 reaction steps), it proved to be computationally very expensive for the integration of pseudo-detailed mechanism. Hence, it was not included for the further applications. Secondly, an integrated program was developed in MATLAB to integrate the system of non linear ordinary differential equations. In order to overcome the stiffness caused by different time scales, Gear's method was used. Furthermore, a function was developed to calculate the sensitivity of dissolved oxygen profile as well as the hydroperoxide species to the rate constants of each reaction steps. It was proved that the reaction steps can be classified as high sensitive, low sensitive and no sensitive. As a result, the chemical scheme was reduced and applied in the CFD calculations. It is very important to take in consideration the fact that fuel sample faces different temperature regimes through the various compartments of the AFTSTU. Unfortunately, due to the experimental constraints it was impractical to have an online measurement of jet fuel chemical compositions at tube inlet. Therefore, by the application of perfectly stirred reactor based on the residence time and temperature of each compartment, the species boundary condition for the tube inlet was calculated