Pakistan management of green transportation and environmental pollution: a nonlinear ARDL analysis

Environmental Science and Pollution Research - Modern advances in nonlinear modeling have exposed that nonlinear models yield more robust results compared with linear models. Research on the effect...     

Globalization toward environmental sustainability and electricity consumption to environmental degradation: does EKC inverted U-shaped hypothesis exist between squared economic growth and CO2 emissions in top globalized economies

Environmental Science and Pollution Research - The study inspects the inverted U shape of the environmental Kuznets curve (EKC) hypothesis following the influence of economic growth on CO2...     

Transformation mechanism and fate of dissolved organic nitrogen (DON) in a full-scale drinking water treatment

Dissolved organic nitrogen (DON) has attracted much attention in drinking water treatment due to its potential to produce nitrogenous disinfection by-products (N-DBPs). This work was designed to explore the transformation and fate of DON and dissolved inorganic nitrogen (DIN) in drinking water treatment. The changes of DON and formation of N-DBPs were evaluated along the water treatment route (i.e., pre-ozonation and biological-contact oxidation, delivery pipes’ transportation, coagulation-sedimentation, sand filtration, post-ozonation, biological activated carbon, ultrafiltration and disinfection) of drinking water treatment plant (DWTP). The transformation mechanism of DON was comprehensively investigated by molecular weight fractionation, three-dimensional fluorescence, LC-OCD (Liquid Chromatography-Organic Carbon Detection), total free amino acids. A detailed comparison was made between concentrations and variations of DON and DIN affected by seasons in the drinking water treatment. Regardless of seasonal variation in raw water concentration, the DON removal trends between different treatment processes remain constant in the present study. Compared to other treatment processes, pre-ozonation and coagulation-sedimentation exhibited the dominant DON removal in different seasons, i.e., 11.13%-14.45% and 14.98%-22.49%, respectively. Contrary, biological-contact oxidation and biological activated carbon negatively impacted the DON removal, in which DON increased by 1.76%-6.49% in biological activated carbon. This may be due to the release of soluble microbial products (SMPs) from bacterial metabolism, which was further validated by the rise of biopolymers in LC-OCD.     

Changes in pH and organic acids in mucilage of Eriophorum angustifolium roots after exposure to elevated concentrations of toxic elements

The presence of Eriophorum angustifolium in mine tailings of pyrite maintains a neutral pH, despite weathering, thus lowering the release of toxic elements into acid mine drainage water. We investigated if the presence of slightly elevated levels of free toxic elements triggers the plant rhizosphere to change the pH towards neutral by increasing organic acid contents. Plants were treated with a combination of As, Pb, Cu, Cd, and Zn at different concentrations in nutrient medium and in soil in a rhizobox-like system for 48–120 h. The pH and organic acids were detected in the mucilage dissolved from root surface, reflecting the rhizospheric solution. Also the pH of root–cell apoplasm was investigated. Both apoplasmic and mucilage pH increased and the concentrations of organic acids enhanced in the mucilage with slightly elevated levels of toxic elements. When organic acids concentration was high, also the pH was high. Thus, efflux of organic acids from the roots of E. angustifolium may induce rhizosphere basification.     

Prenatal diagnosis of recurrent Larsen syndrome: Further definition of a lethal variant

Larsen syndrome is characterized by multiple congenital joint dislocations and flattened facies. Some cases have been familial, with both autosomal dominant and recessive patterns of inheritance. Reports of a form of Larsen syndrome, lethal in the neonatal period, are reviewed. We present a family in which recurrence of the syndrome was diagnosed prenatally, but a lethal outcome again resulted despite preparation for anticipated perinatal complications. Because of the wide clinical variation and the lack of a known metabolic defect, delineation between the various forms of Larsen syndrome is difficult. While the lethal variant appears to be a combination of the Larsen phenotype and pulmonary hypoplasia, other features noted in the lethal cases, such as abnormal palmar creases and laryngotracheomalacia, are also seen in patients with Larsen syndrome who survive.     

Potentially toxic elements in soil of the Khyber Pakhtunkhwa province and Tribal areas,Pakistan: evaluation for human and ecological risk assessment

Environmental Geochemistry and Health - Potentially toxic elements (PTEs) contaminations in the soil ecosystem are considered as extremely hazardous due to toxicity, persistence and bioaccumulative...     

Health risk assessment of hexachlorocyclohexane in soil,water and plants in the agricultural area of Potohar region,Punjab, Pakistan

Environmental Geochemistry and Health - As the largest organ of the human body, the skin is the major exposure route of NO2. However, the evidence for a relationship between NO2 exposure and...     

The dirty energy dilemma via financial development and economic globalization in Pakistan: new evidence from asymmetric dynamic effects

Environmental Science and Pollution Research - Energy strategy has been an essential strand in the view of economists in achieving rapid development process of any country. The recent wave of...