Assessing the effectiveness of speed limit reduction in Edmonton: A case study analysis.

This study evaluates the impact of reducing the default speed limit from 50 km/h to 40 km/h on traffic safety and drivers' behavior in Edmonton, Canada. The research comprehensively examines collision and speed data to assess the outcomes of the new speed limit. Collision data was analyzed across three distinct periods: pre-COVID (2017-2019), the COVID period (2019-2021), and the after-implementation period (August 2021 to July 2022). Speed surveys were conducted on 219 road segments before and after the implementation of the speed limit change. The study utilized a before-and-after with a comparison group approach to evaluate the impact on collisions, using 50 km/h roads that maintained their speed limit throughout as the comparison group. The impact of the reduced speed limit on road safety was assessed by analyzing collision data for two periods, pre-COVID (2017-2019) and COVID (2019-2021), compared to the period after setting the new speed limit (2021-2022). Two-sample t-tests were employed to examine the change in speeds. The analysis revealed statistically significant reductions in the overall number of collisions and injuries and fatalities resulting from collisions, by 25% and 31%, respectively. The study also categorized neighborhoods and roads to demonstrate the areas that experienced the greatest benefits. Speed data showed statistically significant reductions in the average and 85th percentile speeds, with drivers lowering their speeds at 115 locations, accounting for 53% of the surveyed locations. Moreover, higher speed reductions were observed on local roads compared to collector roads, and narrower roads compared to wider roads.. Overall, the study demonstrates that reducing the speed limit can lead to lower speeds and fewer collisions on the roads, creating a safer road environment for drivers, pedestrians, and cyclists. Additionally, it provides a detailed framework for municipalities to evaluate the effectiveness of their speed limit reduction programs.

Exploring the associations between winter maintenance operations, weather variables, surface condition, and road safety: A path analysis approach.

This paper aims to assess the effects of snow and ice control operations by investigating the interdependency between weather variables, maintenance operations, pavement friction, and collisions. Using a disaggregated event-based and location-specific framework, and employing the statistical techniques of Structural Equation Modeling and Path Analysis, all the significant direct and indirect effects of weather variables and maintenance operations on pavement friction and collision occurrence during snowstorms have been identified. It was revealed that precipitation, extremely low temperatures, and the potential of black ice formation all had significant negative direct effects on pavement friction and significant indirect negative effects on traffic safety. Moreover, the application of anti-icing agents and plowing operations have been shown to significantly improve pavement friction and in return improve traffic safety indirectly. To illustrate how the maintenance operations improve traffic safety, a hypothetical snowstorm example was considered. According to the model, anti-icing application was associated with a 14% reduction in collisions, plowing operations resulted in a 33% reduction in collisions, and combining the two tools reduced collisions per snowstorm by 42%. The findings of this paper can help transportation agencies make more informed decisions to promote an efficient mobilization of the existing winter road maintenance services and resources while improving the safety of the traveling public during the winter months.

Umbilical hernia in cirrhotic patients: outcome of elective repair.

Cirrhotic patients with umbilical hernia have an increased likelihood of complications following repair. The aim of this study was to assess the outcomes of elective umbilical hernia repair in cirrhotic patients. Fifty patients having uncomplicated umbilical hernia with a cirrhotic liver were studied prospectively. These patients divided into three groups' according to Child-Turcotte-Pugh (CTP) classification. After management of coagulopathy, correction of hypoalbuminaemia and electrolytes imbalance, and control of ascites, all patients underwent elective hernia repair under regional anesthesia. A comparison was made between the three groups as regard the size of the defect in the linea Alba, operative time, postoperative morbidity and mortality, length of hospital stay, time of return to daily life and postoperative changes in liver function tests (LFTs) in relation to the regional anesthesia applied. hernioplasty was done under spinal anesthesia in 13 patients (26%), under epidural anesthesia in 10 patients (20%), under intercostal nerve block in 7 patients (14%), and under local anesthesia in 20 patients (40%). There was an increased safety (less changes in LFTs) in cases done under local anesthesia and intercostal nerve block. The overall complications rate was 30%. There was an increased complications rate towards the decompensated cases. The differences in the mean length of hospital stay and mean time of return to daily life are statistically significant between the three groups. Umbilical hernia recurrence rate was 2% and no mortality was reported in the study groups.

Snake bite: clinical presentation, complication and outcome in relation to time of polyvalent snake antivenin in Yemen.

The snakebite envenoming is an important medical emergency. The envenoming is a complex medical emergency involving the site of the bite as well as multiple organ system. The symptoms and signs depend on the type and amount of venom injected, location of bite, victims' age, body size and general health conditions. This study clarified the clinical presentations; factors involved in complications and the outcome in relation to timing of polyvalent snake antivenin administration in 50 Patients were selected from cases admitted to Al-Salam Hospital at Saadah, Republic of Yemen. The manifestations of envenoming and complications were recorded. Treated patients were analyzed to determine the factors involved in complications and the outcomes in relation to the timing of polyvalent snake antivenin administration The bitten patients had envenoming (80%), bitten at night (68%), while walking barefooted (84%), complaining from pain (76%) and limb swelling (56%). The systemic manifestations were common only in severe cases and patients attend to the hospital after six hours from snake bite. All patients had envenoming developed coagulation abnormalities. Two cases (4%) died from cerebral hemorrhage and multi organ failure.