Injury severity of single-vehicle large-truck crashes: accounting for heterogeneity

This research examines the injury severity of single-vehicle large-truck crashes in Florida while exploring the role of heterogeneity. A random parameter ordered logit (RPOL) model was applied to 27,505 single-vehicle large-truck crashes from 2007 to 2016 in Florida, and the contributing factors were identified. Random parameters and interaction effects were introduced to the model to determine the heterogeneity and its potential sources. The results suggested that driving speed of 76-120 mph and defective tires were the most influential factors in crash injury severity, increasing the probability of severe crashes. Regarding truckers' attributes, asleep or fatigued conditions and driving under the influence were correlated with a higher possibility of severe crashes. Interestingly, the results showed that truckers from outside the state of Florida were less likely to cause severe single-vehicle large-truck crashes compared to their Floridian counterparts. Y-intersections were also found as a high-risk location for single-vehicle large-truck crashes, leading to more severe outcomes. Regarding heterogeneity, the results indicated that the impacts of driving speed (26-50 mph) and light condition (dark - not lighted) significantly varied among the observations, and these variations could be attributed to driver action, vision obstruction, driver distraction, roadway type and roadway alignment.

Exploring the influences of personal attitudes on the intention of continuing online grocery shopping after the COVID-19 pandemic

The unprecedented COVID-19 pandemic has brought drastic changes in our daily activities. One of these essential activities is grocery shopping. In compliance with the recommended social distancing standards, many people have switched to online grocery shopping or curbside pickup to minimize possible contagion. Although the shift to online grocery shopping is substantial, it is not clear whether this change would last in the long term. This study examines the attributes and underlying attitudes that may influence individuals' future decisions on online grocery shopping. An online survey was conducted in May 2020 in South Florida to collect data for this study. The survey contained a comprehensive set of questions related to respondents' sociodemographic attributes, shopping and trip patterns, technology use, as well as attitudes toward telecommuting and online shopping. A structural equation model (SEM) was applied to examine the intervening effects of observed as well as latent attitude variables on the likelihood of online grocery shopping after the outbreak. The results indicated that those with more experience in using online grocery shopping platforms were more likely to continue purchasing their groceries online. Individuals with positive attitudes toward technology and online grocery shopping in terms of convenience, efficiency, usefulness, and easiness were more likely to adopt online grocery shopping in the future. On the other hand, pro- driving individuals were less likely to substitute online grocery shopping for in-store shopping. The results suggested that attitudinal factors could have substantial impacts on the propensity toward online grocery shopping.

Exploring the attitudes of Millennials and Generation Xers toward ridesourcing services

This paper presents a study investigating the potential market of ridesourcing services, with a focus on the attitudinal and preferential differences between Millennials and Generation Xers. Data obtained from a stated preference survey were utilized, where the respondents were asked to choose between a conventional mode (private vehicle driver, transit, or private vehicle passenger) and ridesourcing modes (exclusive ride and shared ride). Error component nested logit models were developed for Generation Xers and Millennials, respectively. Latent attitudes derived through factor analysis were incorporated into models. A wide range of attitudinal indicators, including general mobility attitudes, perceived benefits and concerns of shared mobility services, reasons for or against owning a car, reasons for ridings Autonomous Vehicles (AV), and the most desired AV features were considered to extract latent attitudes. Model results indicated distinct mode choice behavior between Millennials and Generation Xers. For Generation Xers, the choice to switch to ridesourcing was highly dependent on the perceived time and cost benefits of shared mobility. On the other hand, Millennials' choices were more likely to be influenced by their attitudes or desire toward technology, on-demand services, and driving stress relief. Interestingly, the joy of driving showed a negative impact on Millennials' use of shared-ride services only. The findings from this study provide a more in-depth understanding of the distinct behavior of Generation Xers and Millennials toward shared mobility services, which could help develop strategies and policies to focus more effectively on the needs and concerns of individuals based on their characteristics and attitudes and help promote sustainable transportation system.

Chemical composition of Zhumeria majdae essential oil and its effects on the expression of morphine withdrawal syndrome and tolerance to the anticonvulsant effect of morphine on pentylenetetrazole-induced seizures in mice

Regarding the proven anticonvulsant effect of Zhumeria majdae essential oil (ZMEO) in previous studies we were prompted to investigate the ZMEO effects on the tolerance to the anticonvulsant effects of morphine and the morphine withdrawal syndrome. Tolerance to the morphine anticonvulsant effect was induced in mice by subcutaneous injection of 2.5 mg/kg of morphine for 4 days. Subsequent doses of ZMEO (20 mg/kg) were used to study the expression and development of morphine tolerance. Clonidine was used as the standard drug to inhibit the morphine withdrawal syndrome symptoms. To study the ZMEO effect on withdrawal syndrome, mice received appropriate morphine values for 4 days and on the fifth day, 60 min before administration of naloxone. The effective dose of ZMEO was determined and the number of jumps, stands and changes in the dry stool weight, as symptoms of withdrawal syndrome were evaluated. The dose of 20 mg/kg of ZMEO decreased the tolerance in development and expression groups significantly. Counting the number of jumping, standing and defecation were assessed 30 min after morphine and 1 h after the vehicle and clonidine. The dose of 40 mg/kg ZMEO decreased all the signs of withdrawal syndrome significantly. ZMEO was analyzed by GC/MS and linalool (53.1%) and camphor (23.8%) were characterized as the main components. The results suggest that ZMEO possesses constituent(s) that have activity against tolerance to the anticonvulsant effects of morphine and the morphine withdrawal symptoms.

Severity analysis for large truck rollover crashes using a random parameter ordered logit model

Large truck rollover crashes present significant financial, industrial, and social impacts. This paper presents an effort to investigate the contributing factors to large truck rollover crashes. Specific focus was placed on exploring the role of heterogeneity and the potential sources of heterogeneity regarding their impacts on injury-severity outcomes. The data used in this study contained large truck rollover crashes that occurred between 2007 and 2016 in the state of Florida. A random parameter ordered logit (RPOL) model was applied. Various driver, vehicle, roadway, and crash attributes were explored as potential predictors in the model. Their impacts were examined for the presence of heterogeneity. Interaction effects were then added to the random variables in order to detect potential sources of heterogeneity. Model results showed that the impacts of lighting conditions and driving speed had significant variation across observations, and this variation could be attributed to driver actions and driver conditions at the time of the crash, as well as driver vision obstruction. Findings from this study shed light on the direction, magnitude, and randomness of the factors that contribute to large truck rollover crashes. Findings associated with heterogeneity could help develop more effective and targeted countermeasures to improve freight safety. Driver education programs could be planned more efficiently, and advisory and warning signs could be designed in a more insightful manner by taking into account specific roadway attributes, such as sandy surfaces, downhill, curved alignment, unpaved shoulders, and lighting conditions.

Upregulation of VEGF-A and correlation between VEGF-A and FLT-1 expressions in Iranian multiple sclerosis patients

Multiple sclerosis (MS) is among the most common diseases affecting brain and spinal cord. MS progression is characterized by breakdown of blood brain barrier which leads to increased vascular permeability and angiogenesis. Consequently, vascular endothelial growth factor A (VEGF) and its receptors are considered to be important components of MS progression. VEGFA and fms-related tyrosine kinase 1 (FLT1) play important roles in various aspects of MS. In this study, we investigated the relationship between these genes and MS. For this purpose, the expression levels of VEGFA and FLT1 were measured in the blood of 50 relapsing-remitting MS (RR-MS) patients and 50 healthy individuals using TaqMan quantitative real-time PCR. A significant upregulation of VEGFA expression was observed among MS patients compared with controls (p = 0.04). However, the difference in FLT1 gene expression between study groups was insignificant (p = 0.947). In addition, there was a significant positive correlation between VEGFA and FLT1 genes expressions (r = 0.769, p < 0.0001). In spite of the highly complex molecular mechanisms behind this, the findings imply participation of VEGFA in the pathogenesis of MS.

Expression analysis of protein inhibitor of activated STAT (PIAS) genes in IFNβ-treated multiple sclerosis patients

Objectives

Protein inhibitors of activated STAT (PIAS) are transcription co-regulator of the Janus kinase/signal transducer and activator of transcription signaling pathway as well as nuclear factor-κB family of transcription factors. Both of them are involved in cytokine release during inflammatory response.

Patients and methods

Considering the role of cytokine imbalance in the pathogenesis of multiple sclerosis (MS), we compared blood expressions of PIAS1-4 genes in 48 interferon β (IFNβ)-treated MS patients with those of healthy subjects by means of real time PCR.

Results

Although the expression levels of these genes were not significantly different between MS patients and healthy subjects, significant inverse correlations have been found between PIAS1 expression and age at disease onset. PIAS2 and PIAS3 expressions were inversely correlated with Expanded Disability Status Scale (EDSS) in patients. Moreover, PIAS3 expression was correlated with disease duration in patients and with age in controls. In addition, PIAS4 expression was inversely correlated with EDSS and age at disease onset while it was positively correlated with disease duration.

Conclusion

The present study provides evidences for altered expression of PIAS genes in IFNβ-treated MS patients compared with healthy subjects. However, future studies are needed for elaboration of their exact function in this disorder.

In situ neutron powder diffraction study of the reaction M2O3 ↔ M3O4 ↔ MO, M = (Fe0.2Mn0.8): implications for chemical looping with oxygen uncoupling

The structural properties of (Fe_0.2Mn_0.8)_xO_y as a function of temperature under differing oxidizing and reducing atmospheres have been investigated using thermal gravimetric analysis and neutron powder diffraction techniques.

Selective transport of silver ion through a supported liquid membrane using hexathia-18-crown-6 as carrier

A facile supported liquid membrane (SLM) system for the selective and efficient transport of silver ion is introduced. The SLM used is a thin porous polyvinyldifluoride membrane impregnated with hexathia-18-crown-6 (HT18C6) dissolved in nitrophenyloctyl ether. HT18C6 acts as a specific carrier for the uphill transport of Ag+ ion as its picrate ion paired complex through the SLM. In the presence of thiosulfate ion as a suitable stripping agent in the strip solution, transport of silver occurs almost quantitatively after 4 h. The selectivity and efficiency of silver transport from aqueous solutions containing other Mn+ cations such as Mg2+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Cd2+, Hg2+, Fe3+ and Cr3+ ions were investigated.

Dopamine compared with dobutamine in experimental septic shock: relevance to fluid administration

The hemodynamic effects of dopamine and dobutamine (at doses of 6 micrograms X kg-1 X min-1) were compared during fluid resuscitation from septic shock induced by endotoxin (3 mg/kg) in the dog. In the first part of the study, when a standard amount of saline solution was infused (in 24 dogs), dopamine infusion resulted in higher cardiac filling pressures than did dobutamine infusion, whereas dobutamine infusion resulted in higher cardiac output. In the second part of the study, when fluid infusion was titrated to maintain pulmonary artery balloon-occluded pressure at constant level (in 24 dogs), the total amount of fluids was significantly greater with dobutamine than when dopamine was used (109 +/- 13 vs 71 +/- 10 ml/kg). The combination of dobutamine with fluids resulted in significantly greater stroke volume (39.6 +/- 3.8 vs 21.0 +/- 4.0 ml, P less than 0.05) and oxygen consumption (194 +/- 18 vs 144 +/- 8 ml/min, P less than 0.05). The different effects of dopamine and dobutamine on cardiac filling pressures can be due to differences in effects on myocardial contractility, ventricular afterload, and cardiac compliance. This experimental study indicates that when fluid therapy is combined with adrenergic agents in resuscitation from septic shock, dobutamine can be associated with higher cardiac output and oxygen transport and can result in higher tissue oxygen consumption than dopamine.

Ultimate survival from septic shock

Detailed hemodynamic course during prolonged (less than 12 h) septic shock was studied in 23 patients, of whom 12 ultimately died from sepsis. Hemodynamic presentation was similar in fatalities and in survivors, except for a higher heart rate and a markedly higher blood lactate in fatalities (8.4 +/- 1.4 vs. 3.7 +/- 0.4 mEq/l, P less than 0.01). During fluid resuscitation, the pulmonary artery occlusive pressure associated with the highest left ventricular stroke work was usually around 17 mmHg, but in some patients above 20 mmHg. During the course of septic shock, left ventricular function improved in both fatalities and survivors, so that an altered cardiac function had no ultimate pejorative implication. The higher blood lactate in the absence of a different hemodynamic pattern tends to indicate that peripheral distributive defect remains the essential anomaly in septic shock. Arterial lactate appears to represent the most reliable indicator of ultimate prognosis in septic shock.

Haemodynamic, gasometric and haematological effects of air infusion in dogs: leukotriene inhibition with U-60,257

Air embolization has been shown to produce a reversible permeability-type of pulmonary oedema. The present study investigated the haemodynamic, gasometric and haematological changes associated with air infusion in the spontaneously breathing dog (weight 31 +/- 5 kg). Air was infused at a rate of 10 ml X min-1 for 60 min (10 dogs) or 180 min (5 dogs). During the air infusion, a dramatic increase in pulmonary artery pressure was associated with only a moderate increase in right atrial pressure and limited decreases in arterial pressure and in cardiac output. A marked decrease in end-tidal PCO2 reflected the increase in dead space. These changes were stable during air infusion, but rapidly reversed after the end of infusion. However, hypoxaemia, defined by a decreased PaO2/PAO2 ratio, deteriorated with time and was only partially reversible. At histological examination, interstitial pulmonary oedema was present around the pulmonary arterioles. Air infusion was associated with rapid decreases in circulating leukocytes and platelets and complement activation. Since leukotriene release might be associated with leukocyte activation in this model, seven additional dogs were pretreated by inhalation of 10 mg of the leukotriene inhibitor U-60,257. The increase in pulmonary vascular resistance and in pulmonary shunt were moderately reduced and the drop in circulating leukocytes and platelets was strikingly abolished in the treated animals. Air infusion in the spontaneously breathing dog represents a model of very stable and reversible pulmonary hypertension. It can reproduce important pathophysiological features implicated in the development of pulmonary oedema.(ABSTRACT TRUNCATED AT 250 WORDS)