Manganese content of Tradescancia species exposed to automotive combustion of methylcyclopentadienyl manganese tricarbonyl in urban and rural landscapes

The purpose of this study is to assess the effect of manganese (Mn) from methylcyclopentadienyl manganese tricarbonyl (MMT) on grass (Tradescancia) species beside the major urban and rural highways in the greater Toronto area. Grass clippings were collected at distances up to 40 m from the roadside of a wooded, weakly exposed site (E+) and two unwooded, highly exposed sites (E++ and E+++) to Mn contamination. Statistical tests, including analysis of variance and correlation coefficients, were used to compare the Mn deposition on grass species with respect to distance and traffic density. A higher deposition of Mn was expected at the highly exposed sites when compared with the weakly exposed site, but a significantly higher concentration of Mn was observed at weakly exposed rural E+ site (Mn = 54.07 microg/g; dry wt) than the highly exposed urban E++ (Mn = 38.17 microg/g; dry wt) and E+++ (Mn = 35.63 microg/g; dry wt) sites. A significant correlation coefficient was found for Mn and traffic density (r2 = 0.311, p = 0.0074) at the weakly exposed site than at the highly exposed (r2 = 0.1589, p = 0.1052) urban sites. These data demonstrate that despite the continuous use of MMT in Canadian gasoline, the levels do not appear to exceed the worldwide tolerable levels (17-334 g/g; dry wt) in grass species inhabiting ecosystems next to major highways in urban regions.     

An experimental investigation of a water desalination unit using different microparticle-coated absorber plate: yield,thermal, economic,and environmental assessments

Environmental Science and Pollution Research - This study aims to augment the performance of a solar desalination unit. To experimental examine this idea, a modified solar still with three...     

A review about COVID-19 in the MENA region: environmental concerns and machine learning applications

Environmental Science and Pollution Research - Coronavirus disease 2019 (COVID-19) has delayed global economic growth, which has affected the economic life globally. On the one hand, numerous...     

Analysis of a solar still with photovoltaic modules and electrical heater - Energy and exergy approach

The availability of drinkable water, along with food and air, is a fundamental human necessity. Because of the presence of higher amounts of salt and pollution, direct use of water from sources such as lakes, sea, rivers, and subsurface water reservoirs is not normally suggested. Solar is still a basic technology that can use solar energy to transform accessible waste or brackish water into drinkable water. Exergy analysis is a strong inferential technique for evaluating the performance of thermal systems. Exergy is becoming more popular as a predictive tool for analysis, and there is a rising interest in using it. In this paper, performance analysis on the aspect of energy and exergy from the proposed solar still (PSS) (conventional solar still with the photovoltaic modules-AC heater) was analyzed on three different water depths (W_d) conditions (1, 2, and 3 cm). Using a solar still with an electric heater, the daily potable water production was found as 8.54, 6.37, and 4.43 kg, for the variations in water depth (W_d) of 1, 2, and 3 cm respectively. The energy and exergy efficiency of the PSS at the W_d of 1, 2, and 3 cm were 75.67, 51.45, and 37.21% and 5.08, 2.29, and 1.03%, respectively. At 1 cm W_d, PSS produced the maximum freshwater yield as compared to the other two water depths. When the W_d is increased from 1 to 2 cm and from 1 to 3 cm, the yield is decreased up to 27.3 and 52.7%, respectively. Similarly, the energy and exergy efficiency is decreased up to 36.8 and 53.2% and 50.4 and 80.6%, respectively. The water cost of the modified solar still is calculated as 0.028 $/kg for the least water thickness.

     

Cost-effectiveness of interventions to prevent road traffic injuries in low- and middle-income countries: A literature review

Objective: The objective of this study was to identify, critically appraise, summarize, and synthesize evidence from cost-effectiveness analyses (CEAs) of interventions aimed at preventing road traffic injuries (RTIs) in low- and middle-income countries (LMICs) by age group and road users targeted.

Methods: A search strategy was applied to 12 electronic databases for studies published between May 2002 and August 2015 that met prespecified inclusion criteria. Additional studies were identified by contacting authors and searching bibliographies. Included studies were critically appraised against published criteria and a narrative synthesis was conducted including a use of the strength of evidence criteria.

Results: Five studies were included in the final review that reported 9 interventions. Only 2 out of 9 interventions (drink-drive legislation with enforcement via breath testing campaign and combined interventions for reducing RTIs) showed moderate evidence of being cost-effective, whereas the evidence of cost-effectiveness of other interventions was weak. Only 2 interventions (bicycle and motorcycle helmet use legislation and enforcement) were explicitly targeted to children, young people and vulnerable road users such as pedestrians and cyclists. The cost-effectiveness of interventions to prevent RTIs in LMICs ranged from US$4.14 per disability-adjusted life years (DALYs) averted for building speed bumps at the most dangerous junctions that caused 10% of junction deaths in the area studied to US$3,403 per DALYs averted for legislation and enforcement of helmet use by motorcyclists in the World Health Organization (WHO) sub-Saharan Africa region.

Conclusions: Evidence of cost-effectiveness of interventions to prevent RTIs in LMICs is limited, particularly for children, young people, and vulnerable road users. Evaluation of the effectiveness and cost-effectiveness of a larger number of possible road safety interventions in a variety of LMIC settings is warranted to generate the evidence base for effective traffic injury prevention programs.