Comparison of the retinal and choroidal structures in 3 refractive groups

Objectives: This study investigated the retinal layer thickness, choroidal thickness (CT), and retinal nerve fiber layer (RNFL) parameters in 3 refractive groups. Methods: A total of 201 eyes of 201 subjects were enrolled in this prospective and comparative study. The patients were divided into 3 groups according to refractive status: Group 1 consisted of 60 eyes of myopic subjects, Group 2 comprised 72 eyes of emmetropic subjects, and 69 eyes of hyperopic subjects were categorized as Group 3. The retinal layer thickness, CT, and RNFL parameters were measured using optical coherence tomography and compared between groups. Results: The mean age of the patients was 22.33±10.11 years in Group 1, 21.55±8.3 years in Group 2, and 23.73±11.08 years in Group 3 (p=0.741). Group 1 consisted of 34 women and 26 men, Group 2 contained 44 women and 28 men, and Group 3 was made up of 45 women and 24 men (p=0.124). The mean spherical equivalent value was −6.16±2.01 D in Group 1, 0.13±0.5 D in Group 2, and 5.48±1.32 D in Group 3 (p<0.001). The RNFL and macular thickness values were lower in the myopic patients compared with those of the other groups (p<0.05). The CT measurement was lower in the myopic patients and higher in the hyperopic patients compared with the emmetropic patients (p<0.05). Conclusion: The myopic patients had a lower CT and RNFL thickness measurement than the emmetropic and hyperopic patients, whereas the hyperopic patients had a higher CT than the other patient types

Yayaların Karşıya Geçme Davranışları ve Tercihleri: Bir Saha Çalışması

The planning of the walkable environment is gaining more and more attention due to its various benefits related to public, sustainability, or social life. Therefore, there is an increasing need for knowledge about the concept of walking and the walking behaviors of pedestrians in the built environment. During the pandemic period, as the interest in public transportation decreased in many countries, interest in non-motorized travel options increased and influenced the countries' policies. In this respect, walking is one of the most preferred transportation modes as a sustainable urban transportation mode. However, pedestrians are one of the most vulnerable road user groups in traffic, and therefore pedestrians face many risky situations in traffic. Most accidents involving pedestrians occur when pedestrians cross the street because it is a possible situation for pedestrians-vehicle interaction or conflict. Statistics indicated that in Turkey, the reason for approximately 7% of pedestrian accidents is not to slow down at pedestrian and school crossings and not to give pedestrians the right of way (General Directorate of Security, 2020). In the light of all these, countermeasures that emphasize pedestrian safety should be considered in the planning of cities, and the effective use of pedestrian crossings should be encouraged by these design features. Understanding the crossing behavior of pedestrians is critical for deciding effective countermeasures to increase pedestrian safety. Pedestrian crossing behavior is influenced by various factors such as personal characteristics, traffic conditions, and environmental factors. In this context, this study examines pedestrian behaviors and the factors affecting pedestrian behavior in Ankara-Tunalı Hilmi Street. Tunalı Hilmi Street has an approximate length of 1.5 km. Due to its location close to the city center, it is an area with high traffic and pedestrian density. A 250-meter-long section starting from Tunalı Hilmi Street to Tunus Street was selected as the study area. This study aims to understand the behaviors, perceptions, and preferences of pedestrians in the study area. In addition, it aims to identify situations that create safety concerns for pedestrians in the area and offer suggestions addressing these concerns. For this purpose, a survey study and an observational study are planned to be conducted. An online survey will be designed to reach more people. People who live and work around the study area will be contacted by delivering brochures advertising the study and from social media platforms. The survey will include questions about road user demographics (e.g., age, gender), opinions about the site, crossing behaviors, and preferences. The expected results of the survey are to determine the crossing preferences of pedestrians, understand their motivation when crossing the street, understand the main reason for the attitude regarding traffic rules, and understand the safety perceptions about the area. In addition, it is expected that the situations that negatively affect road safety in the area for pedestrians will be understood. The observation study was planned by dividing the study area into three parts according to its spatial characteristics. The observation study involves taking 30-minute recordings from different angles, capturing the pedestrian mobility in these three parts. The observation data aims to give information about crossing points (whether it is on a pedestrian crossing), crossing time, pedestrian crossing volumes, pedestrian crossing behavior (whether pedestrians are walking, running, or whether it is a group crossing). From the observation study, the preferred location for pedestrians to cross (e.g., crossing patterns) are expected to be determined. It is also expected that the observation data will provide information about the compatibility of pedestrian facilities with pedestrians. As a result of these studies, the suggestions aiming to increase pedestrian safety in this area are planned to be offered. In addition, it is thought that the results of this study will contribute to the determination of the factors affecting the crossing behaviors of pedestrians related to the external environment. As a result, it will help to arrange crossing facilities according to pedestrian preference because the proper design of facilities contributes to pedestrian safety and encourages walking without sacrificing safety and comfort. References: General Directorate of Security. (2020, December). Monthly Traffic Statistics Bulletin. http://trafik.gov.tr/kurumlar/trafik.gov.tr/04-Istatistik/Aylik/aralilk20.pd

Estimation of cerebral surface area of the newborn brain using stereological methods

Objective: In this study, normal values of the newborn brain’s volume and surface area were calculated for the early diagnosis of disease related to the central nervous system which may develop in newborns. Materials and Methods: In this study we investigated MRI images of 5 newborn cadavers. Stereologic measurements were performed to calculate the volume and surface area of the brain. We used Archimedes principle as a gold standard and the point counting method as a stereologic method for volume estimation of the newborn brains. Cycloid probe was superimposed on images,which were obtained by using the vertical section method, for suface area estimation of the brain and then results were obtained. Results: We estimated the mean cerebral volume as 246±79.4 cm3 and 256±71.1cm3 , by the point counting technique and gold standard, respectively. We estimated cerebral surface area using the vertical section method in 4 orientations, the results were 210±41, 202±36.4 cm2 , 267±41 cm2 and 293±52.6 cm2 two post processing, coronal and sagittal planes, respectively. Conclusion: We consider that our study will be a good source for similar studies performed in future