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Shrinkage of lakes is considered a serious ecological challenge. The impact of this phenomenon on the environment can be devastating. Monitoring the spatiotemporal variations of lake's water surface and its salinization is essential for planning and adopting mitigation measures. In this study, a new multiscale-kernel-based method was used to assess the spatiotemporal variations of the shrinkage of the Urmia Lake and develop soil salinity vulnerability map for its basin. For this aim, remote sensing, empirical wavelet transform (EWT), differential symbolic entropy (DSE), and Gaussian regression process (GPR) techniques were used. Vulnerable areas were identified using geo-environmental parameters extracted from the in situ observations and satellite datasets. In the next step, considering three time periods including the lake normal period, lake drying period, and lake restoration period, the variations in the quality of groundwater were investigated. Results showed that the east and south sections of the lake were more prone to severe salinization. Saline lands caused negative impacts on air quality and agricultural activities in these areas. It was found that both climate change and human activities had contributed to the shrinking of the lake. Results showed that the quality of groundwater in the area around the lake has been affected by the excessive salinity of the lake water and the encroachment process of saline water. The water quality index has increased during the drying period of the lake and caused negative effects on the quality of water used for drinking and agricultural activities. In the lake restoration period, a slight increase in water quality was observed., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In addition to the waste of resources and economic losses, environmental damage by gas flaring is widespread and significant. Since flaring the associated gas gives no added value in exchange for its pollution and greenhouse gas (GHG) emissions, it could be identified as a top priority for mitigation. Iran is the third gas flaring country after Russia and Iraq among those facing this issue, and is responsible for 12.1% of the world's gas flaring. While the necessity of developing a method for the precise estimation of flaring GHG emissions is clear, especially for evaluating the result of countries' efforts to meet their nationally determined contribution target, there are huge uncertainties and discrepancies in the values of emission factors among various data sources due to the lack of actual measurements of the volume and diversity of the composition of flare gas. This study aimed to fill the gap in providing authentic data on Iran's gas flaring GHG and air pollutant emissions by developing a model based on satellite data on flare volumes, gas compositions, and combustion equations. Our results revealed that based on 2021 data on flaring volume, Iranian gas flares are emitting approximately 50 million metric tons of CO 2 equivalent to the atmosphere annually, which could be reduced to 43 by only enhancing the flares' efficiency. It accounted for 5.5%-6% of the total GHG emissions of the country. Integr Environ Assess Manag 2023;19:735-748. © 2022 SETAC., (© 2022 SETAC.)

Sudden diverging channels are one of the energy dissipaters which can dissipate most of the kinetic energy of the flow through a hydraulic jump. An accurate prediction of hydraulic jump characteristics is an important step in designing hydraulic structures. This paper focuses on the capability of the support vector machine (SVM) as a meta-model approach for predicting hydraulic jump characteristics in different sudden diverging stilling basins (i.e. basins with and without appurtenances). In this regard, different models were developed and tested using 1,018 experimental data. The obtained results proved the capability of the SVM technique in predicting hydraulic jump characteristics and it was found that the developed models for a channel with a central block performed more successfully than models for channels without appurtenances or with a negative step. The superior performance for the length of hydraulic jump was obtained for the model with parameters F 1 (Froude number) and (h 2- h 1 )/h 1 (h 1 and h 2 are sequent depth of upstream and downstream respectively). Concerning the relative energy dissipation and sequent depth ratio, the model with parameters F 1 and h 1 /B (B is expansion ratio) led to the best results. According to the outcome of sensitivity analysis, Froude number had the most significant effect on the modeling. Also comparison between SVM and empirical equations indicated the great performance of the SVM.

In recent years, iron oxide nanorods find a lot of applications including drug delivery, cell separation, hyperthermia and magnetic resonance imaging. In this study the cytotoxicity of iron oxide nanorods was evaluated based on mouse fibroblast cell behavior and wistar rat's liver and kidney function. At first for modification, nanorods were added to Dulbecco's modified Eagle's medium (DMEM) which contained a lot of sources of vitamins, amino acids, proteins in Fetal Bovine Serum (FBS). The MTT assay was employed for evaluating the toxic effects of 200 and 400 μg/mL modified and non-modified iron oxide nanorods on L929 mouse fibroblast cells in a 24h period. Changes in cell granularity and size as well as cell cycle were investigated using flow cytometry. Moreover liver and kidney function test and serum iron level measurement were performed 24h after the injection of modified iron oxide nanorods via the tail peripheral vein of wistar rats. Results indicated that greater concentration of modified iron oxide nanorods had no significant effect on cell viability while greater concentration of non-modified iron oxide nanorods significantly decreased cell viability. Modified iron oxide nanorods did not have significant effects on cell cycle. The results of liver and kidney function tests did not differ significantly while a significant increase in serum iron level was observed. After H&E staining of slices, there were no changes on morphology of rat's kidney and liver cells. This study suggests that short-time use of 200 and 400 μg/mL iron oxide nanorods are probably safe. Further studies are needed for investigation of toxic effects of different concentrations, coatings, and exposure time periods of iron oxide nanorods., (Copyright © 2015 Elsevier GmbH. All rights reserved.)