Risk factors for being the at-fault driver: A case–control study

Objective: It is estimated that road traffic accidents are globally responsible for approximately 1.2 million deaths and 20 to 50 million injuries. About 70% of traffic incidences (TIs) occur in developing countries and among countries with high TI rates; Iran is the first. The aim of this study was to measure the association between being responsible for a traffic accident and some vehicle, human; and environmental related factors in Yasuj, a city with a high incidence of road traffic injuries and deaths in Iran.

Methods: This is a time-, date-, and place-matched case–control study conducted in 2015 using all traffic accidents registered and investigated by police during 2012. In total, 194 drivers were considered the at-fault driver in a traffic accident and the 194 drivers in the same collisions were included in the analysis.

Results: Based on the results from multivariate conditional logistic regression, significant associations between vehicle maneuver (OR_{Turn to right or left/Moving forward} = 11.10, 95% confidence interval [CI], 1.77–69.58, P = .01) and age (odds ratio [OR] = 1.11, 95% CI, 1.004–1.22, P = .04) and the chance of being an at-fault driver were found.

Conclusion: Driver behavior–related interventions including training and law enforcement seem to be more effective in reducing road traffic accidents in Iran.     

Comparison of different static methods for assessment of AMD generation potential in mining waste dumps in the Muteh Gold Mines,Iran

Acid mine drainage (AMD) gives rise to several problems in sulfide-bearing mineral deposits whether in an ore body or in the mining wastes and tailings. Hence, several methods and parameters have been proposed to evaluate the acid-producing and acid-neutralizing potential of a material. This research compares common static methods for evaluation of acid-production potential of mining wastes in the Muteh gold mines by using 62 samples taken from six waste dumps around Senjedeh and Chah-Khatoun mines. According to a detailed mineralogical study, the waste materials are composed of mica-schist and quartz veins with a high amount of pyrite and are supposed to be susceptible to acid production, and upon a rainfall, they release acid drainage. All parameters introduced in different methods were calculated and compared in this research in order to predict the acid-generating and neutralization potential, including APP, NNP, MPA, NPR, and NAGpH. Based on the analytical results and calculation of different parameters, all methods are in a general consensus that DWS-02 and DWS-03 waste dumps are acid-forming which is clearly attributed to high content of pyrite in samples. DWS-04 is considered as non-acid forming in all methods except method 8 which is uncertain about its acid-forming potential and method 7 which considers a low potential for it. DWC-01 is acid-forming based on all methods except 8, 9, 10, and 11 which are also uncertain about its potential. The methods used are not reached to a compromise on DWS-01 and DWC-02 waste dumps. It is supposed that method 7 gives the conservationist results in all cases. Method 8 is unable to decide on some cases. It is recommended to use and rely on results provided by methods 1, 2, 3, and 12 for taking decisions for further studies. Therefore, according to the static tests used, the aforementioned criteria in selected methods can be used with much confidence as a rule of thumb estimation.     

Experimental and Numerical Analysis of CO Concentration Dispersion of Vehicular Exhaust Emissions in Isolated Environment

Numerical and experimental analyses were applied to carbon monoxide (CO) concentration dispersion to monitor air quality in an enclosed residential complex parking area in Tehran. Firstly, the parking area was preliminary assessed through verifying the characteristics of the problem including the geometry and boundary conditions. Then, proportion of vehicular exhaust emissions was estimated and eventually experimental and numerical analyses were performed. In order to perform numerical calculation, a three-dimensional model was created to numerically simulate the enclosed residential complex parking area by FLUENT software that solves flow governing equations with finite volume method. In FLUENT, species model was selected to assess the dispersion of CO in flow domain. In experimental analysis, CO concentration was measured using sampling bags with a volume of 10 l in 4 min at 6 different points. The sample air was drawn into sampling bags by electric pumps. The findings show that the maximum amount of CO concentration is above the permissible standard recommended by the World Health Organization. Pollutant accumulation was significant in confined areas. In the place where openings exist, the level of accumulation was lower than other areas. The findings obtained from numerical simulation are in complete accord with experimental results.     

Mid-depth oil concentration due to vertical oil dispersion in a regular wave field

An experimental program is organized to investigate the vertical oil dispersion of surface oil spills in a regular wave field. Various waves characteristics and different volumes of oil spills are tested to assess the oil concentration variations at two sampling stations. It is found that the oil concentration due to vertical oil dispersion follows an ascending diagram to reach a maximum and then decreases while oil slick passes the location. The maximum mid-depth oil concentration (C_max) at the farther sampling station is 30–50 % less than the concentration at the closer sampling station to the spill location. A 50 % increase in oil spill volume causes 30–60 % growth in oil concentrations. The relations between oil concentration and important parameters such as wave characteristics, amount of spilled oil and the distance of sampling stations from the spill location are indicated and also oil concentration variations are quantified. Two equations are derived through statistical analysis of the obtained experimental data, which estimate the magnitude and time of maximum oil concentration.     

Hospital waste generation and management in some provinces of Iran

The purpose of this investigation was to determine the rate of generation of different kinds of hospital waste and its management in 11 provinces of Iran in 2012. Waste samples were separated into two categories (domestic type and infectious waste) and weighed daily for 4 weeks, distributed over four seasons to determine quantities and composition. Data on waste management were collected through a questionnaire and interviews of hospital personnel. The total generation of hospital waste ranged from 2.3 to 4.6 kg bed-day^?1 for Razavi Khorasan and Sistan &; Baluchistan provinces. Generation of infectious waste varied from 1.0 to 1.7 kg bed-day^?1 for Sistan &; Baluchistan and Markazi provinces. The lowest and highest percentages of infectious waste generation were found in Golistan (3.8%) and Fars (15.3%). It was also revealed that management of sharps, infectious, and other hazardous wastes was not properly done. A segregation program must be implemented and each fraction of hospital waste must be collected and disposed of separately.     

On the risk of extinction of a wild plant species through spillover of a biological control agent: Analysis of an ecosystem compartment model

Invasive plant species can be controlled by introducing natural enemies (insect herbivores) from their native range. However, such introduction entails the risk that the introduced herbivores attack indigenous plant species in the area of introduction. Here, we study the effect of spillover of a herbivore from a managed ecosystem compartment (agriculture) to a natural compartment (non-managed) and vice versa. In the natural compartment, an indigenous plant species is attacked by the introduced herbivores, whereas another indigenous plant species, which competes with the first, is not attacked. The combination of competition and herbivory may result in extinction of the attacked wild plant species. Using a modelling approach, we determine model parameters that characterize the risk of extinction for a wild plant species. Risk factors include: (1) a high attack rate of the herbivores on the wild non-target species, (2) niche overlap expressed as strong competition between the attacked non-target species and its competitor(s), and (3) factors favouring large spillover from the managed ecosystem compartment to the natural compartment; these include (3a) a high dispersal ability, and (3b) a moderate attack rate of the introduced herbivore on the target species, enabling large resident populations of the insect herbivore in the managed compartment. The analysis thus indicates that a high attack rate on the target species, which is a selection criterion for biocontrol agents with respect to their effectiveness, also mitigates risks resulting from spillover and non-target effects. While total eradication of an invasive plant species is not possible in the one-compartment-one-plant-one-herbivore system, natural enemy spillover from a natural to a managed compartment can make the invasive weed go extinct.     

Numerical simulation of airflow and particle distributions with floor circular swirl diffuser for underfloor air distribution system in an office environment

Environmental Science and Pollution Research - In the present study, an underfloor air distribution (UFAD) system with a circular swirl diffuser was simulated in an office room using a...