This study compiled data to assess the prevalence as well as the pattern of abuse and dependency among substance dependent patients in the United Arab Emirates (UAE). Two hundred and fifty patients from the UAE National Rehabilitation Centre were recruited. Data were collected using a questionnaire at an interview with patients who provided consent to participate. The prevalence of substance abuse and dependency correlated with factors such as age, martial status and education level. Opioid and alcohol were the two most common substances of abuse and dependence, and most susceptible age group was 18 to 29 year olds. The most vulnerable group in the community was young adults. Considering the religious and cultural expectations of the society in the region, there is an urgent need to measure the magnitude of the problem, estimate the burden of disease on the health care system and evaluate the risk factors of substance dependency
Pioglitazone (PIO) is used for the treatment of type 2 diabetes mellitus. There is some evidence that it may lead to improved ventricular function in diabetic patients. The aim of this study was to investigate the effects of various concentration of PIO on electrical conduction in the Goto-Kakizaki (GK) type 2 diabetic rat heart. Blood glucose was higher in GK rats compared to controls and was progressively reduced in GK rats treated with increasing concentrations of PIO. Modest reductions in heart rate and increases in heart rate variability in GK rats compared to controls were not additionally altered by PIO. Prolonged PQ interval in GK rats compared to controls was not additionally altered by PIO.
INTRODUCTION: The purpose of the paper is emphasize the value of a multidisciplinary approach to the improvement of the dental water supply in a community hospital. METHODOLOGY: Samples of water were taken from specified sites within the dental clinic following standard operating procedures and sent to the Rahba laboratory for microbiological study. RESULTS: The dental water reaching the patient was found initially to have levels of contamination above acceptable levels. Through the application of quality tools the team was able to identify areas for improvements. Following implementation of these improvement initiatives, control charts were employed to measure variations in the results and to assess if the initiatives produced sustainable improvement. CONCLUSION: A multidisciplinary team approach to improving the quality of dental water contributed to better understanding the multifactorial causes of dental water contamination. Opportunities for improvement were captured and the latest innovations in the science of water treatment were introduced.
Fiber reinforced polymers (FRPs) have been recently used for retrofitting and strengthening of existing structures. The behavior of mechanically fastened FRP-steel joints under different fastening parameters is still questionable. The current study is conducted experimentally considering nine hybrid FRP-steel joints with variable number of washers-per-bolt. The experimental program focuses on exploring the influence of the number of washers-per-bolt on the load carrying capacity and ductility of the assembly. Experimental results show the significant effect of washers on the failure modes of the tested joints. Results indicate that utilization of washers significantly enhances the load carrying capacity of the hybrid joints. Economical evaluation is considered to identify the optimal number of washers-per-bolt for practical applications.
A coupled plasticity-damage constitutive model (AK Model) is applied to predict fracture propagation in rocks. The quasi-brittle material model captures anisotropic effects and the distinct behaviour of rocks in tension and compression. Calibration is realized using experimental data for Carrara marble. Favourable comparison between model predictions and experiments for single-flawed specimens reveal that the AK model is reliable and accurate for modelling fracture propagation in rocks.
The Weibull distribution function is used to model heterogeneity effects in a coupled plasticity-damage model (AK Model) suitable for predicting fracture propagation in rocks. This is implemented by spatial variation of Young's modulus in Carrara marble. While the AK Model proves capable of capturing heterogeneity effects, results for single-flawed specimens confirm that Carrara marble is a nearly homogeneous material.
The fiber reinforced polymer (FRP) contribution to the shear behaviour of reinforced concrete beams is the subject under consideration of much recent and current research.This thesis proposal deals with the shear retrofitting of large scale reinforced concrete (RC) beams already failed in shear which will be repaired with externally bonded carbon fiber reinforced polymer (EB CFRP) laminates. The parameters that affect the RC beams strengthened in shear with FRP will be examined, which includes the FRP ratio and the interaction with internal shear reinforcement (stirrups). The shear strength recovery will then be obtained by comparing the original strength of the beams to that of the repaired beams which will help to estimate the shear contribution provide by the FRP. The results will be used to assess the shear contribution provided by FRP as adopted by the current design guidelines such as the ACI and the fib14.
One of the major problems encountered in artificial gas lifting is the stability of production from wells were gas lift may show a highly oscillatory behavior, and hence production varies greatly with time. This paper presents methodology of design of a gain scheduling strategy based on a new physical model of artificial gas lift in oil wells. The model was preliminary validated by comparing the states dynamics with other models from the literature which have been replicated. The Modified Relay- Feedback-Test (MRFT) method was used to calculate the PI controller parameters, and the model reached steady state for different operating points. Gain scheduling was then performed following the MRFT results to provide a simple PI controller tuning parameters for the automatic control and optimization of the production from the oil well, and to compensate for the casing-heading instability in the system.
The Modified relay feedback test (MRFT) was recently proposed for non-parametric tuning of PID controllers. In the present research, the use of the MRFT for identification of process dynamics is proposed and investigated. It is shown that the use of the MRFT allows one to ensure identification of process linear dynamics in the frequency domain, with frequencies generated automatically in the frequency range most important for a considered process. It is proposed that identification is done through minimization of a specific cost function that characterizes matching of the frequency response "theoretical phi function" obtained from the Locus of Perturbed Relay System (LPRS) analysis plot of the model to the points of the locus of the process obtained experimentally via MRFT. The proposed methodology is illustrated by an example of identification of dynamics of an experimental liquid level control setup.
Artificial gas lift system utilizes the fact that pressure differential exists in the reservoir's tubing leading to enhanced oil recovery. Studies were conducted to control this process as it improves stability and performance of gas lift. The current industrial practice depends on flow measurements as process variable, yet, and does not depend on the down-hole measurement that are technically difficult to approach due to the technology limitations. Proper knowledge of the model of this process along with the states would leads to a better controller design for this system. This research sheds the lights on the design of a sliding mode observer. The purpose of the observer is to acquire the states of a nonlinear system representing the physical system of a gas lift process in oil wells. The proposed design of an observer is based on measurements taken above the surface only. The presented work considers sliding mode observers.
