228 research outputs found
What obese and non-insulin dependent diabetes mellitus patients experience and expect from their primary care doctors concerning weight-loss management
M.Fam.Med. Faculty of Health Sciences, University of the Witwatersrand, 2009.Worldwide, obesity prevalence is rapidly rising. Doctors have poor understanding of what patients experience and expect from them regarding weight-loss management. This qualitative study explored what obese patients with Non-insulin Dependent Diabetes Mellitus experience and expect from their primary care doctors concerning weight-loss management. Free attitude interviews were conducted with eight participating patients. The findings showed that doctors encouraged and counselled patients regarding weight-loss, mainly giving dietary advice, but did not routinely weigh them. Patients accepted responsibility for losing weight, trusted their doctors, valued their advice highly and did not want referrals to gymnasiums or dieticians. They expected doctors to advise them practically about exercise, diet and weight-loss goals, weigh them regularly and communicate effectively. They believed that doctor-patient relationships and interaction are important in weight-loss management, patients should be treated on an individual basis and the process should be empowering. Medical intervention costs were not problematic for this group. Generally patients were satisfied with their doctors but there were areas concerning patients’ expectations that primary care doctors should take cognisance of
Paediatric dental chair sedation: a Gauteng-based pilot study
BACKGROUND: Procedural sedation and analgesia (PSA) is generally safe, and
often necessary to successfully undertake dental procedures in children. Providing
PSA in dental rooms avoids expenses generated by having to perform procedures in
operating theatres, but this must not be done at the cost of patient safety. Although
rare, severe adverse events that occur are usually preventable. Death and
permanent neurological injury are unacceptable outcomes for healthy children being
sedated for minor procedures.
OBJECTIVES: The objectives of this study were to determine the proportion of
dental practitioners making use of paediatric dental chair PSA in Gauteng, describe
their PSA practice, and to determine adherence to recommended safety standards
Travel Time Reliability Estimation: Use of Median Travel Time as Measure of Central Tendency
This paper proposes use of median travel time compared to mean travel time as the measure of central tendency to calculate Buffer Time Index (BTI), one of the most important measures of travel time reliability. This study examined gamma, exponential, largest extreme value, smallest extreme value, logistic, Weibull, lognormal and log-logistic distributions to determine the best fit to travel time data for two cases: 24 hours and peak hours for a highway with Variable Speed Limit (VSL) conditions. the goodness-of-fit tests indicated that the log-normal distribution best represented the travel time data for peak periods and log-logistic distribution better fitted the travel time data for 24 hours. the log-logistic distribution and log-normal distributions were positively skewed and for skewed distributions, median is the best estimate of central tendency. Hence, median travel time is proposed for calculating BTI. the difference in values of BTIs were evaluated when mean and median travel time were used. Travelers must add extra time to their average travel time to ensure on-time arrival. It was found that this extra time increases from 11% to 30% when median travel time is used as the average travel time compared to mean travel time for calculation of BTI. © 2011 ASCE
Exploring the reactivity of 2-trichloromethylbenzoxazoles for access to substituted benzoxazoles
The reactivity of 2-trichloromethylbenzoxazoles towards various nucleophiles, under metal free or iron-catalyzed conditions, for the synthesis of substituted benzoxazoles is described. These methods allow for selective substitution at either the 2- or 2’- position of the benzoxazoles using the same starting materials / reagents. This approach allows for the controlled synthesis of a variety of key derivatives from a single 2-trichloromethylbenzoxazole starting material
Slip Ramp Spacing Design for Truck Only Lanes using Microscopic Simulation
For the Corridors of the Future project, slip ramps will provide access to trucks between the proposed truck-only lanes (TOLs) and general-purpose lanes (GPLs) for trucks to exit using at-grade interchanges. This paper proposes recommendations for slip ramp spacing between the TOLs and the general GPLs along Missouri rural interstate highways using a microscopic simulation model, VISSIM. Simulation of peak period traffic conditions indicated that heavy vehicle speeds were directly proportional to the lengths of the merge, diverge, and link sections. the proposed design recommendations for slip ramp spacing are based on the results of these section lengths. Central composite design was used to generate the cases required for simulation. to ascertain the findings of the simulation study, Level-of-Service for the segments on GPL was determined. This paper provides practitioners and state Departments of Transportation with design recommendations for slip ramp spacing and lengths of merge, link, and diverge for the Corridors of the Future project. © 2011 ASCE
Professionalism in medical students at a private medical college in Karachi, Pakistan
Objective: To determine levels of professionalism in undergraduate medical students at a private medical college and assess how changes emerge during their training.
Methods: The study was conducted at Aga Khan University, a tertiary care teaching hospital, during November and December 2011. Freshmen, Year 3 and Year 5 students were requested to fill out a questionnaire. It was designed to assess the participants\\u27 levels of professionalism and how they perceived the professional environment around them by incorporating previously described scales. The questionnaire was re-validated on a random sample of practising clinicians at the same hospital. SPSS 17 was used for statistical analysis.
Results: The study sample comprised 204 participants. The mean score for level of individual professionalism was 7.72±3.43. Only 13 (6.4%) students had a score one standard deviation above the faculty mean. About 24 (11.8%) were one standard deviation and 35 (17.2%) were 2 standard deviations below the faculty mean. The remaining 130 (63.7%) were \u3e2 standard deviations below the faculty mean. Considering the level of education, the mean score for level of professionalism was 8.00±3.39 for freshmen, 6.85±3.41 for year 3 students, and 8.40±3.34 for year 5 students.
Conclusion: The currently employed teaching practices inculcating the values of professionalism in medical students are serving as a buffer to maintain the pre-training levels of professionalism from declining
Systematic Evaluation of a Variable Speed Limit System in St. Louis Missouri
This paper presents the systematic evaluation of Variable Speed Limit (VSL) system implemented on I-270 in St. Louis County. the system varies the speed limit in real time during periods of recurring and non-recurring congestion to prevent traffic from breaking down. the system was evaluated objectively and subjectively, and this paper describes the objective evaluation of the system. the objective evaluation was performed by comparing the traffic flow parameters during static speed limit (pre-VSL) with variable speed limit (post-VSL) by using five measures of performance: 1) speed, 2) volume, 3) occupancy, 4) travel time, and 5) congestion measures. Identification of congested segments and the time periods for the analyses were the initial steps for evaluating the system. Traffic data were provided by MoDOT collected using Remote Traffic Microwave Sensors. Average speed, volume and time occupancy profiles indicated that the vs.L system change in traffic conditions including congestion. Preventing the highway from reaching its capacity and avoiding the traffic breakdown is one of the main objectives of vs.L system initiation. It can be achieved by upstream drivers reducing speed, metering the upstream traffic and preventing traffic from breaking down. Congestion measures evaluation indicates change in Travel Time, Percentage of Congested Travel and reduction in duration, extent and intensity of congestion. they vs.L system benefits were determined, which indicated that the system benefits will pay for the initial capital cost of the system over the years. This study can be used by Departments of Transportation for evaluation of active management systems. © 2011 ASCE
Microsimulation models incorporating both demand and supply dynamics
There has been rapid growth in interest in real-time transport strategies over the last decade, ranging from automated highway systems and responsive traffic signal control to incident management and driver information systems. The complexity of these strategies, in terms of the spatial and temporal interactions within the transport system, has led to a parallel growth in the application of traffic microsimulation models for the evaluation and design of such measures, as a remedy to the limitations faced by conventional static, macroscopic approaches. However, while this naturally addresses the immediate impacts of the measure, a difficulty that remains is the question of how the secondary impacts, specifically the effect on route and departure time choice of subsequent trips, may be handled in a consistent manner within a microsimulation framework.
The paper describes a modelling approach to road network traffic, in which the emphasis is on the integrated microsimulation of individual trip-makers’ decisions and individual vehicle movements across the network. To achieve this it represents directly individual drivers’ choices and experiences as they evolve from day-to-day, combined with a detailed within-day traffic simulation model of the space–time trajectories of individual vehicles according to car-following and lane-changing rules and intersection regulations. It therefore models both day-to-day and within-day variability in both demand and supply conditions, and so, we believe, is particularly suited for the realistic modelling of real-time strategies such as those listed above. The full model specification is given, along with details of its algorithmic implementation. A number of representative numerical applications are presented, including: sensitivity studies of the impact of day-to-day variability; an application to the evaluation of alternative signal control policies; and the evaluation of the introduction of bus-only lanes in a sub-network of Leeds. Our experience demonstrates that this modelling framework is computationally feasible as a method for providing a fully internally consistent, microscopic, dynamic assignment, incorporating both within- and between-day demand and supply dynamic
Application of Spatial Statistics in Transportation Engineering
“Everything is related to everything else, but near things are more related than distant things” is the first law of geography. It can be hypothesized that spatially, occurrence of a crash can exhibit similarities. To identify spatial patterns of crashes, this chapter presents spatial autocorrelation techniques such as Moran’s I and the Getis-Ord Gi*statistics; spatial interpolation such as kriging; and nonparametric probability density function and kernel density (K). The aim of this chapter is to provide application of spatial statistics in transportation engineering specifically to identify crash concentrations and patterns of clusters in a study area
Acceleration Behavior of Drivers in a Platoon
A new dual-regime acceleration model was developed to represent the acceleration behavior of drivers in a platoon of vehicles. Two sets of field data collected by aerial photographic techniques were used to assess the validity of the proposed and existing acceleration models. A single regime acceleration model failed to present the acceleration behavior of drivers. The field data indicated that at around 13 m/sec the acceleration rate drops. Thus, two different acceleration rates, higher acceleration rate at lower speeds and lower acceleration rate at higher speeds, were used to provide the best fit to the data. This provided realistic acceleration behavior of drivers in a platoon. The field data sets were collected about 10 years apart. The improvements in acceleration capability of a platoon of vehicles from two different time periods were determined. Improvements in performance of vehicles were quantified using the above mentioned field data. The method of quantification can also be used to predict and model the performance of vehicles currently in use. Inversely, current vehicles can be downgraded to represent vehicles of past years and thus make use of already collected data. Important uses of the dual regime model are in modeling the traffic flow behavior and designing roadway elements that depend on acceleration behavior of drivers
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