AN OVERVIEW OF ROAD SAFETY IN LEBANON

Road traffic injuries are a growing public health and development problem. According to the World Health Organization (WHO), 1.2 million people are killed in road traffic crashes around the world each year. Most of those killed are in the prime of their lives. The road traffic deaths represent a picture of the total waste of human and societal resources from road injuries. Between 20 and 50 million people are injured or disabled by road crashes around the world (WHO, 2012). In Lebanon, a Middle Eastern country, over 1000 people are killed every year, with nearly onethird involving vulnerable road users like pedestrians and motorcyclists. More than twice as many are permanently disabled by their injuries. These statistics need to be multiplied and seen in the context of deep family tragedy, of unimaginable grief and anguish, and of tremendous health and economic and disability costs

Project-level instantaneous emission modeling from mobile sources for freeway lane closure using SHRP2 Naturalistic Driving Study data and microscopic traffic simulation

This dissertation is one of the first studies which used the Second Strategic Highway Research Program (SHRP2) Naturalistic Driving Study (NDS) data to perform modal emission modeling at the project-level. SHRP2 NDS was the largest naturalistic driving study to date conducted in the U.S. which included instrumented vehicles with over 3,000 drivers that were recruited from six states. There is great potential to apply this data in modeling emissions as it will capture differences in driver behavior, roadway geometry, traffic conditions and their impact on emissions. The dissertation had two primary objectives: (1) apply the SHRP2 NDS data to model instantaneous exhaust emissions from passenger vehicles at four-lane divided freeway segments with work zones, and (2) examine the accuracy of microscopic traffic simulation models to replicate real-world vehicle trajectories in order to estimate emissions at work zones. Research studies related to assessing the impact of lane closure on vehicular emissions are limited considering that collecting data from field observations is resource intensive and expensive. In addition, the application of microsimulation models instigates certain constraints because various driver behavior and lane changing parameters must calibrated to ensure that the output from traffic simulation models can represent accurate real-world driving activity. Therefore, the first study focused on utilizing the vehicle kinematics data collected as part of the SHRP2 NDS to model emissions from passenger cars for work zones employed on four-lane divided principal arterials. The emissions models in this study considered different work zone configurations and varying congestion levels. Furthermore, the second analysis examined the ability of Vissim microsimulation model to replicate field conditions. A generic guidance to calibrate the driver behavior parameters in Vissim for freeway lane closure was applied and findings were compared to field observations from the SHRP2 study. Three different construction scenarios were implemented, i.e. AM-peak hour, PM-peak hour and nighttime off-peak lane closure

Evaluation of systemic safety methodologies on low-volume rural paved roadways

Prioritizing locations in rural areas has been a major concern to various transportation agencies due to the wide-spread nature of crashes on rural roadways. A systemic (more proactive) approach is required to rank sites in this case since the traditional hot spot method only considers crash data. The thesis was based on a prioritization project funded by Mid-America Transportation Center (MATC). Several systemic safety methodologies were explored and summarized in the report. However, one technique was selected, i.e. Minnesota CRSP approach, on the basis of a decision-making matrix that included five factors. The selected technique was applied on secondary paved rural roadways in Buchanan and Dallas counties in Iowa. Data was collected along 197 miles in Buchanan County and 156 miles in Dallas County. Initial prioritized ranking lists were generated for the three transportation elements (horizontal curves, stop-controlled intersections and rural segments) that were identified in the Minnesota CRSP approach. The tool was then evaluated to determine if a change in the weight/coefficient of risk factors in each transportation element would have a statistical impact on the prioritized list. Three different sensitivity analysis approaches were designed and tested. Results showed no statistical significance in the shift of rankings for all cases. A top 20 analyses was then conducted to evaluate the number of sites that shifted from the prioritization lists compared to the initial ranking. A maximum of 50 percent shift was recorded for rural horizontal curves in Dallas County when the third sensitivity analysis approach was applied

The Yellow and Red Supergiants of M33

Yellow and red supergiants are evolved massive stars whose numbers and locations on the HR diagram can provide a stringent test for models of massive star evolution. Previous studies have found large discrepancies between the relative number of yellow supergiants observed as a function of mass and those predicted by evolutionary models, while a disagreement between the predicted and observed locations of red supergiants on the HR diagram was only recently resolved. Here we extend these studies by examining the yellow and red supergiant populations of M33. Unfortunately, identifying these stars is difficult as this portion of the color-magnitude diagram is heavily contaminated by foreground dwarfs. We identify the red supergiants through a combination of radial velocities and a two-color surface gravity discriminant and, after re-characterizing the rotation curve of M33 with our newly selected red supergiants, we identify the yellow supergiants through a combination of radial velocities and the strength of the OI $\lambda$7774 triplet. We examine ~1300 spectra in total and identify 121 yellow supergiants (a sample which is unbiased in luminosity above log(L/L\odot) ~ 4.8) and 189 red supergiants. After placing these objects on the HR diagram, we find that the latest generation of Geneva evolutionary tracks show excellent agreement with the observed locations of our red and yellow supergiants, the observed relative number of yellow supergiants with mass and the observed red supergiant upper mass limit. These models therefore represent a drastic improvement over previous generations.Comment: Accepted for publication in the Astrophysical Journa

Rate of Corneal Collagen Crosslinking Redo in Private Practice: Risk Factors and Safety

Objective. To report the rate of progression of keratectasia after primary crosslinking (CXL) and evaluate the safety and efficiency of CXL redo. Materials and Methods. We conducted a retrospective analysis of the patients who underwent CXL between 2010 and 2013 at the Beirut Eye Specialist Hospital, Lebanon. Progression of keratectasia was based on the presence of an increase in maximum keratometry of 1.00 D, a change in the map difference between two consecutive topographies of 1.00 D, a deterioration of visual acuity, or any change in the refraction. Primary and redo CXL were done using the same protocol. Results. Among the 221 eyes of 130 patients who underwent CXL, 7 eyes (3.17%) of five patients met the criteria of progression. All patients reported a history of allergic conjunctivitis and eye rubbing and progressed within 9 to 48 months. No complications were noted and all patients were stable 1 year after CXL redo. Conclusion. Allergic conjunctivitis and eye rubbing were the only risk factors associated with keratoconus progression after CXL. A close followup is thus mandatory, even years after the procedure. CXL redo seems to be a safe and efficient technique to halt the progression after a primary CXL

Numerical modelling of a hemp concrete wall

In a global warming context associated to the abuse of energy consumption, actual researches focus more and more on reducing energy costs in the building sector. This target could be achieved by using innovative building materials, such as hemp concrete, due to its positive impacts on thermal and environmental levels. The aim of this work is to carry out a numerical study of a hemp concrete wall subjected to several indoor and outdoor conditions of temperature and relative humidity using the program object oriented SPARK. The hygrothermal behaviour of the wall is investigated taking into account heat and moisture transfer within the wall as well as hysteresis phenomenon between the sorption and desorption curves and their temperature dependency

Gastric Pouch Gastrointestinal Stromal Tumour Post-Roux-en-Y Gastric Bypass: A First Reported Case

Gastric gastrointestinal stromal tumour is an extremely rare condition to occur after bariatric surgery. To the authors’ knowledge, only two cases of gastric gastrointestinal stromal tumours after Roux-en-Y gastric bypass have been reported in the medical literature, both occurring in the excluded gastric remnant. Herein, the authors report the third case of gastric gastrointestinal stromal tumour post-Roux-en-Y gastric bypass, and the first case to occur in the gastric pouch, which was managed surgically by laparoscopic resection. From here, combining the observations of clinicians treating and following up patients post-bariatric surgery in an international database will be beneficial to patients, and aid in development of surveillance guidelines

Identifying adolescents' gaming preferences for a tobacco prevention social game: A qualitative study.

IntroductionConsidering the dangers of adolescent tobacco use, the successful design of behavioral programs is crucial for tobacco prevention. According to preliminary research, social game interventions can improve adolescent tobacco outcomes. The current qualitative study aims to (1) uncover the gaming elements that adolescents deem important for a positive learning experience, and (2) confirm these gaming elements with adolescents who are presented with a tobacco prevention game concept that applies these elements.MethodsFindings from this study are drawn from two phases. Phase 1 involved in-person focus group discussions (n = 15) and Phase 2 included three online focus groups and a paired interview with another set of adolescents (n = 15). The study was conducted under a project that aimed to design and test a social game-based tobacco prevention program for adolescents (Storm-Heroes). With open coding and thematic analysis, two research team members identified repeated topics and relevant quotes to organize them into themes. The themes evolved as new content was identified during the process. This process was repeated until thematic saturation was reached.ResultsThematic analysis across Phase 1 and Phase 2 revealed four major themes: 1) Balance during gaming challenges, 2) Healthy social interaction, 3) Performance and creative freedom, and 4) Fictional world and game mechanics for tobacco prevention.ConclusionThis study identified specific intervention features that best fit the needs of adolescents in the context of a social game for tobacco prevention. For future research, we will use a participatory approach to allow adolescents to take part in the design process, improve Storm-Heroes, and develop health promotional messages that can be incorporated into the program. Ultimately, a board game for tobacco prevention is expected to bring adolescents together to create lasting memories that nudge them away from tobacco use and the harm it can cause