Impacts of speed variations on freeway crashes by severity and vehicle type

Speed variations are identified as potentially important predictors of freeway crash rates; however, their impacts on crashes are not entirely known. Existing findings tend to be inconsistent possibly because of the different definitions for speed variations, different crash type consideration or different modelling and data aggregation approaches. This study explores the relationships of speed variations with crashes on a freeway section in the UK. Crashes split by vehicle type (heavy and light vehicles) and by severity mode (killed/serious injury and slight injury crashes) are aggregated based on the similarities of the conditions just before their occurrence (condition-based approach) and modelled using Multivariate Poisson lognormal regression. The models control for speed variations along with other traffic and weather variables as well as their interactions. Speed variations are expressed as two separate variables namely the standard deviations of speed within the same lane and between-lanes over a five minute interval. The results, similar for all crash types (by coefficient significance and sign), suggest that crash rates increase as the within lane speed variations raise, especially at higher traffic volumes. Higher speeds coupled with greater volume and high between-lanes speed variation also increase crash likelihood. Overall, the results suggest that specific combinations of traffic characteristics increase the likelihood of crash occurrences rather than their individual effects. Identification of these specific crash prone conditions could improve our understanding of crash risk and would support the development of more efficient safety countermeasures

Ultrasonographic evaluation of first trimester bleeding per vaginum

Background: First trimester is a very crucial period of pregnancy having high risks of pregnancy losses. The objective of this study was to assess the accuracy of ultrasound in diagnosis of cause of first trimester bleeding per vaginum.Methods: 200 women who attended the out-patient department with the complaint of bleeding per vagina in the first trimester pregnancy were taken for the study. Clinical assessment by pelvic examination was done and a provisional diagnosis was made. All necessary routine investigations were done followed by ultrasonographic scan of each patient. All the data was recorded in a proforma.Results: Among these 200 cases, threatened abortion in 72 cases. It was the commonest cause for bleeding. There were 20 cases of ectopic pregnancy out of which 16 were correctly diagnosed. There were 16 cases of missed abortion. There were 8 cases of hydatidi form mole. There were 40 cases of incomplete abortion, 16 cases of inevitable abortion, 8 cases of an embryonic gestation and 20 cases of complete abortion. By this study it is concluded that the accuracy of USG in diagnosing the cause of first trimester bleeding per vaginum is 96%.Conclusions: Use of USG in diagnosis of cause of bleeding in first trimester can lead to accurate and early diagnosis and save the patients from unneeded interventions based on history and clinical examination

Effects of driver work-rest patterns, lifestyle and payment incentives on long-haul truck driver sleepiness

The aim of the study is to identify and model the role of payment incentives, driver work-rest patterns and other lifestyle habits influencing the drowsy driving behavior among long-haul truck drivers. To achieve this aim, this study targeted two main objectives: (1) to examine the significant differences between the groups of drowsy and non-drowsy drivers based on the opportunities of monetary incentives and (2) to examine the role of different factors: driver demographics, work-rest patterns, lifestyle and occupational characteristics particularly incentives associated with driving in causing driver sleepiness among Indian truck drivers. The study is based on interview responses from 453 long-haul truck drivers approached in three Indian cities- Mumbai, Indore and Nagpur. Initial principal component analysis of the responses related to financial incentives (occupational characteristics) resulted into two correlated factors: (i) willingness to earn extra payments if offered (WEP) and (ii) incentives available in the current driving experience (ICD) that influence driver work-rest patterns and alertness while driving. Kruskal-Wallis test showed a significant difference among the groups of sleepy and non-sleepy drivers due to these factors (WEP and ICD). Finally, a logistic regression model showed that long driving duration, working days per week, rest patterns, insufficient sleeping hours and history of violations were found significantly associated with drowsy driving among the long-haul truck drivers. Increase in consumption of caffeine and tobacco indicated reduction in driver alertness. According to the model results, the odds of drowsy driving were 77% less for drivers between 46-55 years compared to the young drivers (<25 years). Driving under the influence of financial incentives was observed to increase the odds of falling asleep by 1.58 times among the truck drivers. This was apparently the most interesting and intriguing result of the study indicating the need for further research on the influence of financial or socio-economic motivations to sleepiness

Temporal and spatial compliance behaviour of pedestrians under the influence of time pressure at signalized intersections: A pedestrian simulator study

Pedestrian safety is at high stakes due to the non-compliance practices of pedestrians at signalized intersections. Additionally, when pedestrians are hurrying, they deliberately engage in such unsafe behaviour. Therefore, the purpose of this study was to understand how time pressure (i.e., feeling of hurry or saving time) affected pedestrians' decisions to follow traffic rules at signalized junctions. To achieve the study objectives, a pedestrian simulator setup was used to collect the crossing behaviour of forty participants at a four-legged signalized intersection. Non-compliance, one of the riskiest pedestrian behaviours, was examined with respect to three different forms, comprising dangerous temporal non-compliance (D-TNC), non-dangerous temporal non-compliance (ND-TNC), and spatial non-compliance (SNC) behaviour under two distinct conditions: baseline (i.e., no time pressure) and time pressure conditions. The effects of demographics, usual walking features, and time pressure on D-TNC and ND-TNC were investigated using a multinomial regression model, while SNC behaviour was investigated using a binary regression model. It was interesting to note that the majority of the factors related to pedestrians’ usual walking behaviour had an impact on all kinds of non-compliance behaviours. Importantly, the results also showcased that time pressure had a contrasting impact on D-TNC and ND-TNC behaviour whereas SNC behaviour increased under time pressure. Additionally, the varying impacts of D-TNC, ND-TNC, and SNC were also reflected in the occurrence of the crashes, which were probably triggered by discrepancies in the influence of time pressure on non-compliance behaviours. These findings highlight the need for technical solutions, educational outreach, and efficient enforcement practices to reduce pedestrians' non-compliant behaviour

Isthmus agenesis with variant topography of levator glandulae thyroideae: A case report

The thyroid gland is an imperative endocrine gland present in the neck known commonly for its morphological variations. During routine dissection agenesis of the isthmus of the thyroid gland was observed with levator glandulae thyroidea extending from both the lateral lobes with stout stalks of pyramidal lobes bilaterally. The Levator glandulae thyroidea is a fibro-musculo-glandular band. usually, present unilaterally or extending from isthmus connecting the pyramidal lobe of the thyroid gland to the hyoid bone. The site of the isthmus is often associated with anastomosis of vessels supplying thyroid gland but strikingly no such anastomosis was observed. The presence of such variant of levator glandulae thyroidea with agenesis of the isthmus is a rare finding and knowledge of such topographical anatomical variations is crucial for understanding associated pathologies related to the thyroid gland and modus operandi in their management

Ultrasonographic evaluation of first trimester bleeding per vaginum

Background: First trimester is a very crucial period of pregnancy having high risks of pregnancy losses. The objective of this study was to assess the accuracy of ultrasound in diagnosis of cause of first trimester bleeding per vaginum.Methods: 200 women who attended the out-patient department with the complaint of bleeding per vagina in the first trimester pregnancy were taken for the study. Clinical assessment by pelvic examination was done and a provisional diagnosis was made. All necessary routine investigations were done followed by ultrasonographic scan of each patient. All the data was recorded in a proforma.Results: Among these 200 cases, threatened abortion in 72 cases. It was the commonest cause for bleeding. There were 20 cases of ectopic pregnancy out of which 16 were correctly diagnosed. There were 16 cases of missed abortion. There were 8 cases of hydatidi form mole. There were 40 cases of incomplete abortion, 16 cases of inevitable abortion, 8 cases of an embryonic gestation and 20 cases of complete abortion. By this study it is concluded that the accuracy of USG in diagnosing the cause of first trimester bleeding per vaginum is 96%.Conclusions: Use of USG in diagnosis of cause of bleeding in first trimester can lead to accurate and early diagnosis and save the patients from unneeded interventions based on history and clinical examination

Modelling work- and non-work-based trip patterns during transition to lockdown period of COVID-19 pandemic in India

COVID-19 pandemic has significantly affected the transportation sector across the world. Implementation of lockdown (that includes restricted travel activities) is a prevention strategy executed by various governments to minimize the spread of COVID-19. India went into complete lockdown from 25th March 2020; however, change in commuter's travel behavior was observed from the third week of March (termed as transition to lockdown) due to pandemic fear. In total 1945 participants participated in the travel behaviour survey and their responses with respect to work-based and non-work-based trips during transition period were analysed to understand their adaptation towards COVID-19. The study also attempted to quantify the effects of influencing factors which can explain change in the commuters’ travel behaviour. The findings revealed that one-year increment in traveller's age had 2% reduced probability of no travel during transition than pre-transition. For non-work-related travel, chances of lower travel frequency were significantly greater during the transition period as compared to pre-transition. Compared to the non-essential trips, the chances of reduced travel frequency for the essential trips were found to be lower by 92%. By examining these behavioural changes, the present study aims to assist the policymakers in understanding the dynamics of fluctuating travel demand with respect to trip purpose during pandemic situations like COVID-19. © 2021 Hong Kong Society for Transportation Studie