Seasonal variation in ambient PM mass and number concentrations (case study: Tehran, Iran)

Tehran, the capital city of Iran, is an important industrial and commercial center. This city is one of the worst cities in the world in terms of air pollution, which is mostly due to mobile sources rather than stationary sources. Particulate matter (PM), which is a complex mixture of extremely small particles and liquid droplets, is considered as an important source of air pollution in Tehran. In this study, our objective was to study PM₁₀, PM_2.5, and PM_1.0 mass and number concentrations and find the correlations of these two parameters in the west-central parts of Tehran during two consecutive warm and cold seasons. The particles collected from five stations were analyzed for their mass and number simultaneously by a laser-based Grimm dust monitor. In general, it was found that the accumulation of the PM in this region is more in the cold season. PM₁₀ mass concentration increases almost twofold and PM_2.5 and PM_1.0 almost three times in this season. The mean number concentration of the particles (0.3–20 μm) was found to be almost 4.8 times in the cold season. It was also noticed that the average dimensions of the particles decrease in that season.     

The potential protective role of apigenin against oxidative damage induced by nickel oxide nanoparticles in liver and kidney of male Wistar rat,Rattus norvegicus

Environmental Science and Pollution Research - Nickel oxide nanoparticles (NiONPs) are involved in several applications but still have some adverse effects. Apigenin (APG) is a widespread natural...     

Experimental selection of Marylynnia puncticaudata (Cyatholaimidae,Nematoda) and effects of organic enrichment

Environmental Science and Pollution Research - Meiobenthic nematodes are well-known bioindicators in aquatic ecosystem health programs. However, the explored taxa are still limited and practically...     

Prenatal diagnosis in a family with X-linked hydrocephalus

The neural cell adhesion molecule L1 is a transmembrane glycoprotein belonging to the immunoglobulin superfamily of cell adhesion molecules (CAMs). Its expression is essential during embryonic development of the nervous system and it is involved in cognitive function and memory. Mutations in the L1CAM gene are responsible for four related L1 disorders; X-linked hydrocephalus/HSAS (H ydrocephalus as a result of S tenosis of the A queduct of S ylvius), MASA (M ental retardation, A phasia, S huffling gait, and A dducted thumbs) syndrome, X-linked complicated spastic paraplegia type I (SPG1) and X-linked A genesis of the C orpus C allosum (ACC). These four disorders represent a clinical spectrum that varies both between and within families. The main clinical features of this spectrum are C orpus callosum hypoplasia, mental R etardation, A dducted thumbs, S pastic paraplegia and H ydrocephalus (CRASH syndrome). Since there is no biochemically assayed disease marker, molecular analysis of the L1CAM gene is the only means of confirming a clinical diagnosis. Most L1CAM mutations reported to date are point mutations (missense, nonsense, splice site) and only a few patients with larger rearrangements have been documented. We have characterised a rare intragenic deletion of the L1CAM gene in a sample of DNA extracted from a chorionic villus biopsy (CVB) performed at 12 weeks' gestation. Copyright © 2005 John Wiley & Sons, Ltd.     

Photocatalytic oxidation of the textile dye basic red 18 with irradiated titanium dioxide

One of the major problems of textile wastewater is the presence of dye materials, because colour is visible to the public even if the dye concentration is lower than other pollutants, and needs therefore to be removed from the wastewater before it is discharged. Techniques based on “advanced oxidative processes” such as photocatalysed oxidation seem to be very promising for industrial wastewater treatment, especially for decolourization of textile effluents. In this work, we describe the photocatalytic degradation of the textile dye Basic Red 18 (BR 18) in aqueous solution using two different types of TiO₂ as photocatalyst: Degussa P25 (80% anatase) and Framitalia (100% anatase). Photooxidation of BR 18 was followed by HPLC analysis, and kinetic parameters were evaluated in order to optimise the treatment procedure. The results obtained in this work showed that the colour became virtually zero and the chemical oxygen demand (COD) is strongly reduced at the end of the treatment. The obtained results are compared with the efficiency of decolourization using the H₂O₂/UV System. Finally, marine mussel test was used to evaluate the efficiency of photocatalytic oxidation with TiO₂ in terms of ecotoxicity. A significant reduction of cumulative mortality was observed for the treated effluent.     

A cascaded fuzzy-LOPA risk assessment model applied in natural gas industry

Natural gas plants demand high amount of energy provided through immense fuel gas units that may suffer risk hazards. Implementing a safety management system is the most efficient way of allocating resources for safety. This paper adopts The Layer of Protection Analysis (LOPA) risk Management associated with Fuzzy Logic methodology to prevent or limit industrial accidents. We provide an innovative cascaded fuzzy-LOPA model for certain hazardous scenarios and at different frequencies of occurrence. The introduced model is tested at moderate and high risk levels controlled in its practical limits through the use of Safety Integrity Functions (SIF). Obtained results show how this fuzzy-LOPA achieves better results to maintain the Safety Integrity Level (SIL) rating to acceptable limits.     

Anti-angiogenic effects of aqueous extract from Agrostemma githago L. seed in human umbilical vein endothelial cells via regulating Notch/VEGF,MMP2/9, ANG2, and VEGFR2

Environmental Science and Pollution Research - Abnormal angiogenesis contributes to the pathogenesis of various diseases. The medicinal usage of Agrostemma githago L. seed (A. githago herein) has...     

Temporal variations of fine and coarse particulate matter sources in Jeddah,Saudi Arabia

This study provides the first comprehensive analysis of the seasonal variations and weekday/weekend differences in fine (aerodynamic diameter <2.5 μm; PM_2.5) and coarse (aerodynamic diameter 2.5–10 μm; PM_2.5–10) particulate matter mass concentrations, elemental constituents, and potential source origins in Jeddah, Saudi Arabia. Air quality samples were collected over 1 yr, from June 2011 to May 2012 at a frequency of three times per week, and analyzed. The average mass concentrations of PM_2.5 (21.9 μg/m³) and PM₁₀ (107.8 μg/m³) during the sampling period exceeded the recommended annual average levels by the World Health Organization (WHO) for PM_2.5 (10 μg/m³) and PM₁₀ (20 μg/m³), respectively. Similar to other Middle Eastern locales, PM_2.5–10 is the prevailing mass component of atmospheric particulate matter at Jeddah, accounting for approximately 80% of the PM₁₀ mass. Considerations of enrichment factors, absolute principal component analysis (APCA), concentration roses, and backward trajectories identified the following source categories for both PM_2.5 and PM_2.5–10: (1) soil/road dust, (2) incineration, and (3) traffic; and for PM_2.5 only, (4) residual oil burning. Soil/road dust accounted for a major portion of both the PM_2.5 (27%) and PM_2.5–10 (77%) mass, and the largest source contributor for PM_2.5 was from residual oil burning (63%). Temporal variations of PM_2.5–10 and PM_2.5 were observed, with the elevated concentration levels observed for mass during the spring (due to increased dust storm frequency) and on weekdays (due to increased traffic). The predominant role of windblown soil and road dust in both the PM_2.5 and PM_2.5–10 masses in this city may have implications regarding the toxicity of these particles versus those in the Western world where most PM health assessments have been made in the past. These results support the need for region-specific epidemiological investigations to be conducted and considered in future PM standard setting.

Implications: Temporal variations of fine and coarse PM mass, elemental constituents, and sources were examined in Jeddah, Saudi Arabia, for the first time. The main source of PM_2.5–10 is natural windblown soil and road dust, whereas the predominant source of PM_2.5 is residual oil burning, generated from the port and oil refinery located west of the air sampler, suggesting that targeted emission controls could significantly improve the air quality in the city. The compositional differences point to a need for health effect studies to be conducted in this region, so as to directly assess the applicability of the existing guidelines to the Middle East air pollution.