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Autonomous truck platoons hold the potential for substantial economic and environmental advantages. However, there is a lack of comprehensive research on the interactions between drivers and different configurations of truck platoons at waving segments. This study aims to contribute to the literature by achieving three primary objectives: (1) examine the effects of various truck platoon configurations on merging and diverging behaviors [time to merge (TTM) and time to diverge (TTD)]; (2) explore the impact of individual characteristics such as age, gender, education level, and driving experience on TTM and TTD; and (3) investigate the decision-making associated with these maneuvers (merging or diverging in front of the platoon, behind the platoon or cut in through the platoon). A driving simulator study was conducted with 85 participants across 12 distinct scenarios, considering variations in platoon size, intraplatoon spacing, and platoon lane-change behavior. Several statistical methods were employed, including ANOVA, the Cox proportional hazards model, and machine-learning techniques, to analyze the factors impacting TTM and TTD. The results revealed that increasing the headway distances between trucks in a platoon to 13.72 m (45 ft) or 18.29 m (60 ft) substantially decreased TTM, enhancing traffic flow. Furthermore, splitting the truck platoon between two lanes of the freeway before the merging point significantly influenced other drivers' merging decisions. When half of the trucks in a platoon switched to the left lane before the merging point, a larger proportion of participants chose to merge ahead of the platoon. Age, gender, education level, and self-assessment of driving skills were all found to significantly influence merging and diverging behaviors. Drivers with higher degrees took longer to merge, whereas older, male, and experienced drivers merged faster. The lowest average TTD was observed when half the platoon switched to the left lane before the diverging point. [ABSTRACT FROM AUTHOR]

Lack of visibility is one of the challenges that impact drivers' ability to perform driving tasks at night. Although prior studies indicated that lighting increases nighttime safety, lighting at stop-controlled intersections is not mandatory according to many U.S. states' guidelines. This paper aims to investigate the impact of different lighting conditions on safety-related driving behavior during nighttime at stop-controlled intersections. The data were collected using a driving simulator experiment where participants drove through several intersections during daytime, nighttime without lighting, nighttime with partial lighting, and nighttime with full lighting. Collected measures included speed, time-to-collision (TTC), and post-encroachment time (PET). TTC/PET were used as safety surrogate measures to evaluate the impact of lighting on drivers' safety. The results indicated that TTC/PET were higher during daytime and nighttime with partial/full lighting. Furthermore, the findings revealed that lower speeds were recorded at nighttime with partial/full lighting. Kruskal–Wallis test revealed that TTC/PET medians for nighttime without lighting were statistically significantly different from TTC/PET medians of the remaining lighting conditions. Moreover, negative binomial modeling indicated that lack of lighting and speed had inverse correlation with TTC. In summary, the results revealed that street lighting at stop-controlled intersections provided 37% increase in TTC, 15% increase in PET, and 15% reduction in speed. [ABSTRACT FROM AUTHOR]

A multiparameter analysis was conducted to evaluate the impact of meteorological parameters, night sky brightness and seismic hazards on proposed sites for the new optical/infrared Egyptian astronomical telescope. The European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis v5 (ERA5) data set is used to obtain the following meteorological parameters: total cloud coverage fraction, precipitable water vapour, relative humidity, wind speed and direction, and air temperature. To estimate the aerosol optical depth, we used the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). Light pollution over the candidate sites was measured using the Visible Infrared Imaging Radiometer Suite (VIIRS) day/night band. In order to assess the seismic hazards for the candidate sites, the seismic input in terms of maximum acceleration and response spectra was computed using a physics-based ground motion approach to assess the seismic hazards and, consequently, the designation of a seismic-resistant structure for the proposed sites. Of the seven nominated sites, two sites are found to have the best measurements and might be considered as future sites for the new Egyptian astronomical telescope. The first site is located in the south of the Sinai peninsula, while the second site is located in the Red Sea mountains region. [ABSTRACT FROM AUTHOR]

Recently, the severity of injuries resulting from traffic crashes has been extensively investigated in numerous studies. However, the number of studies that addressed the severity of the run-off-road (ROR) crashes is relatively low. In the Emirate of Abu Dhabi (AD), approximately 22% of the total serious crashes and fatalities that occurred from 2007 to 2013 were ROR crashes. Despite these facts and the uniqueness of the composition of licensed drivers in AD (approximately 87% of them are non-Emiratis), the factors affecting the occurrence and severity of ROR crashes in AD have not been explicitly addressed in any prior studies. Therefore, this study aims to investigate the characteristics of at-fault drivers involved in ROR crashes in AD, the nature and main causes of those crashes. In this regard, conditional distribution and two-way contingency tables were developed. In addition, this study aims to identify and quantify the factors affecting the severity of ROR crashes such as driver, road, vehicle and environment factors. To achieve this goal, ordered probit model approach was employed. Crash data for a total of 3819 ROR crashes that occurred in AD were employed in the analysis. The results indicated that driver factors (carelessness, speeding, and nationality), vehicle characteristics (vehicle type), and road and environment factors (road type, crash location and road surface condition) were the significant factors influencing the severity of ROR crashes in AD. Countermeasures to improve traffic safety and reduce numbers and severity of ROR crashes in AD were discussed. Key words: run-off-road crashes, crash severity, traffic safety, ordered logit model. La gravite des blessures causees par des accidents de la route a recemment fait l'objet de nombreuses etudes approfondies. Cependant, assez peu d'etudes se sont interessees a la gravite des accidents provoques par une sortie de route (SDR). Dans l'emirat d'Abou Dabi (AD), environ 22 % des accidents graves et mortels denombres entre 2007 et 2013 etaient des accidents causes par une SDR. Malgre cela et en depit de la composition singuliere de la population des conducteurs titulaires d'un permis de conduire dans l'emirat d'AD (environ 87 % d'entre eux n'etant pas des Emiratis), les facteurs qui influent sur le nombre et la gravite des accidents dus a une SDR n'avaient jamais ete serieusement etudies auparavant. Par consequent, la presente etude vise a etudier les caracteristiques des conducteurs de conducteurs responsables impliques dans des accidents provoques par un SDR dans l'emirat d'AD ainsi que la nature et les principales de ces accidents. Pour ce faire, des distributions conditionnelles et des tableaux de contingence a double entree ont ete crees. La presente etude a egalement pour objectif de determiner et de quantifier les facteurs qui influent sur la gravite des accidents causes par une SDR, tels que le conducteur, la route, le vehicule et les facteurs environnementaux. Pour atteindre un tel objectif, une methode sur un modele probit ordonne a ete utilisee. Pour realiser cette etude, on s'est servi des donnees relatives a 3819 accidents causes par une SDR et survenus dans l'emirat d'AD. Les resultats ont montre que les facteurs associes aux conducteurs (manque de vigilance, vitesse de conduite et nationalite), les caracteristiques des vehicules impliques (type de vehicule) et les facteurs environnementaux et lies a la route (type de route, lieu de l'accident et etat de la surface de la route) influaient beaucoup sur la gravite des accidents provoques par une SDR et survenus dans l'emirat d'AD. Des mesures visant a ameliorer la securite routiere et a reduire le nombre et la gravite des accidents dus a une SDR dans l'emirat d'AD sont egalement presentees. [Traduit par la Redaction] Mots-cles: accidents causes par une sortie de route, gravite des accidents, securite routiere, modele logit ordonne., Introduction Run-off-road (ROR) crashes are considered as one of the major causes of fatalities and serious injuries in traffic crashes around the world. Run-off-road crashes occur when the driver loses [...]

The Qatari government introduced a major public transport project titled the Doha Metro system to address the fast growing transportation demands in Qatar's urban areas and to be ready for the Qatar 2022 FIFA World Cup. To benefit from this new metro system in reducing traffic congestion problems in Doha, it must be attractive with a reasonable level of service to attract large numbers of car users to switch to the new metro. This goal can be achieved by a better understanding of the user's needs and expectations in Qatar. This paper aims to identify and quantify the significant factors affecting commuters' perspectives, preferences and tendencies to use this new metro network for their daily trips in the future. The data used for the analysis was obtained from a self-reported questionnaire survey carried out among a sample of commuters living in Doha. Different data mining techniques were employed including conditional distributions and two-way analysis. In addition, logistic regression and structural equation modeling approaches were developed. The results revealed that the location of metro stations, the metro station's features, the metro's features, gender, the number of daily trips, the purpose of trips, and the average duration of trips in Doha were the significant factors that affected commuters' willingness and tendency to use the new metro system. The results of this study provide authorities and decision makers in Doha with valuable insights that should be taken into consideration prior to implementing the new metro service to ensure its success. Key words: public transit, commuters' willingness to use public transit, commuters' satisfaction, service quality, travel mode choice. Resume: Le gouvernement qatari a lance la construction un grand projet de transport en commun, le metro de Doha, pour faire face a la forte croissance de la demande en matiere de transports dans les regions urbaines du Qatar et pour que le pays soit en mesure d'accueillir la Coupe du Monde de la FIFA 2022. Pour etre avantageux et contribuer a reduire les embouteillages a Doha, ce nouveau metro devra offrir un niveau de service acceptable de facon a encourager un grand nombre d'automobilistes a l'emprunter plutot que d'utiliser leur voiture. La realisation d'un tel objectif passera par une meilleure comprehension des besoins et attentes des usagers qataris. Le present article a pour but de determiner et de mesurer les facteurs qui influenceront le plus les intentions, les preferences et les tendances des banlieusards quant a l'utilisation quotidienne de ce nouveau reseau de metro a l'avenir. Les donnees utilisees pour cette analyse proviennent de questionnaires d'enquete auxquels a repondu un echantillon d'habitants de la banlieue de Doha. Diverses techniques d'exploration de donnees ont ete utilisees, dont celle des distributions conditionnelles et l'analyse a deux facteurs. En outre, des modelisations par regression logistique et par equation structurelle ont ete developpees. Les resultats de ces analyses ont montre que l'emplacement des stations de metro, leurs caracteristiques, le sexe des usagers, le nombre de leurs deplacements quotidiens et le but et la duree moyenne des deplacements a Doha constituaient les facteurs qui influenceraient le plus les choix et les tendances des banlieusards quant a l'utilisation de ce nouveau reseau de metro. Les resultats de la presente etude fournissent aux autorites et aux decideurs des donnees precieuses qui devront etre prises en compte avant la mise en service du nouveau metro afin d'en assurer le succes. [Traduit par le Redaction] Mots-cles : transports en commun, volonte des banlieusards d'utiliser les transports en commun, satisfaction des banlieusards, qualite de service, choix du mode de transport., Introduction The increased rate of car use, especially in rich developing countries, has major implications in terms of pollution, noise, and congestion problems. Commuters are relying more on private cars [...]

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On 7th of August 2020, a Mw = 4.9 earthquake occurred in Mila province (Northeast Algeria). Consequently, more than 2000 houses were indirectly affected (partially damaged or collapsed) within 10 km from the earthquake's epicenter, in the locality of El Kherba. According to field surveys conducted 3 days after the earthquake, damages and casualties were directly linked to an earthquake-induced landslide that occurred after the main shock. This was evidenced by numerous cracks in the site's soil mainly perpendicular to the landslide direction. Local characteristics (i.e., geology, geomorphology) and anthropogenic activities expose this area to landslide hazard. This study shows the reliability of the ambient noise horizontal to vertical spectral ratio (HVSR) method in the characterization of an active landslide. Ambient noise records were processed through spectral ratio techniques to identify the landslide's geometry based on spectral responses analysis. The obtained results allowed the landslide's slip surface mapping and boundary delineation, which correlates well with the field observations. After the rotation of the signal's horizontal components, large variations in the experimental spectral ratios, in both amplitude and direction, revealed site effects (soil remoulding, crack network) on the soil dynamic behavior. [ABSTRACT FROM AUTHOR]

Fish semen cryopreservation is a valuable technique to sustain good quality sperm for fertilization, facilitating threatened species conservation and broodstock genetic development. The present investigation aimed to develop suitable standardized protocols to cryopreserve sea bass (Dicentrarchus labrax) semen. Thus, four experiments were conducted to determine the most effective extender (egg-yolk citrate, urea-egg-yolk, and 0.9% NaCl), cryoprotectant (DMSO, glycerol, ethylene glycol "EG", and methanol), sperm/cryodiluent dilution ratio (1:2, 1:4, 1:10, and 1:20) and equilibration time (0, 5, 15, or 30 min) to maintain the sperm content after cryopreservation. The consistency of post-thaw semen was assessed, with motility percentage, motility duration, and fertilization rate all being taken into account. When sperms were thawed, the consistency was at its best, especially when sperm was diluted with a ratio of 1:20 with egg-yolk citrate extender containing 10% DMSO, with a 15-min equilibration period before cryopreservation. Sea bass sperm cryopreserved using this protocol exhibited fertilisation rates, class motility, and motility duration close to fresh semen. Thus, the cryopreservation method developed in the present investigation proved to be an efficient and effective approach to augment the cryosurvival of sea bass spermatozoa. [ABSTRACT FROM AUTHOR]

Pasteurella (P.) multocida and Mannheimia (M.) haemolytica are the most two common pathogenic bacterial agents causing pneumonia in calves. Both bacteria are associated with significant economic losses in the cattle industry due to high morbidity and mortality rates, especially in the case of severe infections. The objectives of the present study were to perform serotyping and genotyping, as well as characterization of the virulence-associated genes in 48 bacterial isolates; 33 P. multocida and 15 M. haemolytica. All strains were isolated from pneumonic cattle calves showing respiratory manifestations such as fever, nasal discharges, and rapid breathing in North Upper Egypt governorates (Beni-Suef and El-Fayoum). PCR was applied as a confirmatory test using a specific universal gene, kmt1, and rpt2 for P. multocida and M. haemolytica, respectively. The results show that 29 (87.9%) P. multocida and 15 (100%) M. haemolytica isolates were positive for the corresponding universal gene. The results of serotyping indicate that 86.2% of P. multocida isolates belonged to serotype B:2, while 13.8% were untyped. Meanwhile, 60% and 40% of M. haemolytica isolates belonged to serotype 2 and serotype 1, respectively. Investigation of virulence-associated genes showed that all the tested P. multocida isolates harbored nanB, omp87, and toxA genes. Four M. haemolytica isolates harbored both gcp and lktC genes and of these, three isolates harbored the ssa gene. Sequencing of toxA gene of P. multocida and lktC gene of M. haemolytica in the current strains indicated a great homology with strains uploaded in gene banks from different hosts and localities worldwide. [ABSTRACT FROM AUTHOR]

Many crashes occur every year that involve drivers who are unlicensed and underage. One of the main challenges for traffic safety authorities is the lack of detailed information about this alarming phenomenon. This study aims to investigate the rate of underage driving among high school teenagers and thoroughly examine their awareness, perception, and use of the seat belt as one of the main in-vehicle safety features. Data was obtained from a self-report questionnaire. The results indicated that 59% of the participants drive without having a driver's license, and 47% reported that they use seat belts as a driver or a passenger. The results of the logistic regression model indicated that four significant factors affected high school teenagers' use of seat belts: (1) driving a car to school or “being a driver,” (2) personal perception of the role of seat belts in saving lives, (3) keen to require back-seat passengers to buckle up, and (4) previous attendance in a safety campaign that emphasized the importance of using seat belts. [ABSTRACT FROM PUBLISHER]

Numerous studies have demonstrated that the human factor is the main contributing factor leading to traffic accidents, followed by vehicle and road factors. In addition, many earlier studies have indicated that young drivers are at a high risk of being killed in traffic accidents around the world. Compared to other age groups, young drivers tend to be over-represented in severe and fatal crashes considering their percentage of the population. One way to improve traffic safety on highways is to improve the driving behavior of drivers, especially teenager drivers. There is a lack of studies that strived to thoroughly examine the driving behavior of young drivers in the Kingdom of Saudi Arabia (KSA). Thus, this study aims at identifying and quantifying the significant factors associated with the involvement of young Saudi drivers in at-fault crashes. Another objective of this study is to provide in-depth insights concerning the types of traffic violations that young Saudi drivers commit while driving and the main reason(s) that they are involved in risky driving behaviors. The data used for the analyses were obtained from a self-reported questionnaire survey carried out among 242 young drivers in Riyadh, the capital of the KSA. To achieve these goals, the structural equation modeling (SEM) approach was adopted using SAS software package. The results indicated that exceeding the speed limit was the main reason for obtaining traffic citations by young Saudi drivers (stated by approximately 73% of participants). Additionally, running late was the main reason for being involved in risky driving behaviors while driving (62%), followed by testing the performance of the car or showing off (18%). Moreover, the results of the SEM model indicated that aggressive violations (pressing the brakes and gas pedal at the same time while driving) was the most significant factor affecting young Saudi drivers' involvement in at-fault crashes between ages 18 and 24, followed by ordinary violations (i.e., driving so close to the car in front that it would be difficult to stop in an emergency) and attitudes toward speeding. Practical suggestions on how to improve the driving behavior of young Saudi drivers and how to reduce their crash risk, along with recommendations for future studies, are also discussed. [ABSTRACT FROM AUTHOR]

This article investigates the factors affecting drivers' stated behavior in adverse visibility conditions and examines whether drivers rely on and follow advisory or warning messages displayed on portable changeable message signs (CMS) and/or variable speed limit (VSL) signs in different visibility and traffic conditions, and on two types of roadways: freeways and two-lane roads. A multiple-approach survey was designed to collect opinions and stated data from Central Florida drivers. Categorical data analysis techniques such as conditional distribution, odds ratio, and chi-squared tests were applied. In addition, two modeling approaches, bivariate and multivariate probit models, were estimated. The results revealed that gender, age, road type, visibility condition, and familiarity with VSL sign were the significant factors affecting the stated likelihood of reducing speed following CMS/VSL instructions in reduced visibility conditions. Other objectives of this study were to determine the content of messages that would achieve the best-perceived safety and drivers' compliance and to examine the best way to improve safety during these adverse visibility conditions. The results indicated that respondents thought that "Caution--fog ahead--reduce speed" was the best message and that using that CMS and VSL signs together was the best way to improve safety during such inclement weather situations. Based on the findings of the present study, several recommendations are suggested as guidelines to improve safety in reduced visibility conditions. [ABSTRACT FROM AUTHOR]

Proteins and proteolytic activities in the contents of the salivary gland (SGc), digestive tract (DTc) and excretory-secretory products (ESP) from larvae of the camel nasal botfly Cephalopina titillator were separated electrophoretically, and characterized. The protein profiles of the different samples were qualitatively quite similar in the larval stages L2 and L3. Zymogram analysis of proteases in the samples indicated that the digestive tract contained a greater variety of proteases than the salivary gland or the excretory-secretory products. They are mainly serine proteases. Proteases of ESP and DTc (especially of 3rd instar) contain trypsin- and chymotrypsin-like serine proteases, while the serine proteases of SGc are not of the trypsin- or chemotrypsin-type.

Studies on the prevalence and virulence genes of Klebsiella mastitis pathogens in a buffalo population are undocumented. Also, the association of rmpA kfu, uge, magA, Aerobactin, K1 and K2 virulent factors with K. pneumoniae buffalo, and cow mastitis is unreported. The virulence of K. pneumoniae was evaluated through both phenotypic and molecular assays. In vivo virulence was assessed by the Vero cell cytotoxicity, suckling mouse assay and mice lethality test. Antimicrobial susceptibility was tested by disk diffusion method. The 45 K. pneumoniae isolates from buffalo (n = 10/232) and cow (n = 35/293) milk were isolated (45/525; 8.6%) and screened via PCR for seven virulence genes encoding uridine diphosphate galactose 4 epimerase encoding gene responsible for capsule and smooth lipopolysaccharide synthesis (uge), siderophores (kfu and aerobactin), protectines or invasins (rmpA and magA), and the capsule and hypermucoviscosity (K1 and K2). The most common virulence genes were rmpA, kfu, uge, and magA (77.8% each). Aerobactin and K1 genes were found at medium rates of 66.7% each and K2 (55.6%). The Vero cell cytotoxicity and LD (50) in mice were found in 100% of isolates. A multidrug resistance pattern was observed for 40% of the antimicrobials. The distribution of virulence profiles indicate a role of rmpA, kfu, uge, magA, Aerobactin, and K1 and K2 in pathogenicity of K. pneumoniae in udder infections and invasiveness, and constitutes a threat for vulnerable animals, even more if they are in combination with antibiotic resistance.

Due to the possibility of utilizing different snails in the combat of Schistosoma in Egypt; it is important to study the role it may play in transmitting other trematodes of medical and veterinary importance. Taking this background into consideration, polymerase chain reaction (PCR) assay was designed to identify trematode species at larval stages in intermediate hosts (cercariae in snails) using a combination of standard and molecular methods. This PCR assay was also applied to naturally infected molluscan in order to assess the use of the procedure for detection. The importance of the present study was to demonstrate the epidemiological situation and application in control.