Investigating global surface temperature from the perspectives of environmental,demographic, and economic indicators: current status and future temperature trend

Environmental Science and Pollution Research - Anthropogenic activities have increased atmospheric concentrations of greenhouse gas emissions, which have observably increased global temperature....     

Presentation of a developed sub-epidemic model for estimation of the COVID-19 pandemic and assessment of travel-related risks in Iran

Environmental Science and Pollution Research - The COVID-19 pandemic is one of the contagious diseases involving all the world in 2019–2020. Also, all people are concerned about the future of...     

Cl~-、SO_4~(2-)和PO_4~(3-)对异养反硝化污泥的胁迫效应

反硝化菌是反硝化作用的驱动者,探明Cl~-、SO_4~(2-)和PO_4~(3-)对异养反硝化污泥(HDS)的胁迫效应,有助于含盐废水生物脱氮技术的研发和优化.选用硝酸盐还原酶(周质酶)和碱性磷酸酯酶(胞内酶)作为指标,考察了不同Cl~-、SO_4~(2-)和PO_4~(3-)浓度对HDS酶活的影响;通过观测HDS中的活菌水平和细胞形态,考察了不同Cl~-、SO_4~(2-)和PO_4~(3-)浓度对HDS微生物细胞结构的影响.结果表明,Cl~-、SO_4~(2-)和PO_4~(3-)对HDS硝酸盐还原酶的半抑制浓度分别为0.15、0.12和0.05mol/L,对碱性磷酸酯酶的半抑制浓度为1.14、0.75和0.49mol/L;高浓度Cl~-、SO_4~(2-)和PO_4~(3-)导致HDS微生物细胞膜结构破损,通透性增加,细胞物质外泄.阴离子对HDS的胁迫可分为渗透胁迫和电荷胁迫,渗透胁迫造成HDS中功能酶失活,电荷胁迫造成HDS中细胞膜破损,细胞物质外泄.     

Amelioration of toxicopathological effects of cadmium with silymarin and milk thistle in male Japanese quail (Coturnix japonica)

Environmental Science and Pollution Research - Cadmium is an important widely distributed heavy metal in the environment due to its several industrial uses, while milk thistle is an important herb...     

Estimating and mapping forest biomass using regression models and Spot-6 images (case study: Hyrcanian forests of north of Iran)

Hyrcanian forests of North of Iran are of great importance in terms of various economic and environmental aspects. In this study, Spot-6 satellite images and regression models were applied to estimate above-ground biomass in these forests. This research was carried out in six compartments in three climatic (semi-arid to humid) types and two altitude classes. In the first step, ground sampling methods at the compartment level were used to estimate aboveground biomass (Mg/ha). Then, by reviewing the results of other studies, the most appropriate vegetation indices were selected. In this study, three indices of NDVI, RVI, and TVI were calculated. We investigated the relationship between the vegetation indices and aboveground biomass measured at sample-plot level. Based on the results, the relationship between aboveground biomass values and vegetation indices was a linear regression with the highest level of significance for NDVI in all compartments. Since at the compartment level the correlation coefficient between NDVI and aboveground biomass was the highest, NDVI was used for mapping aboveground biomass. According to the results of this study, biomass values were highly different in various climatic and altitudinal classes with the highest biomass value observed in humid climate and high-altitude class.     

High yield room temperature synthesis of pyranochromenes in neutral cetyltrimethylammonium bromide micellar media

Pyrano[3,2-c]chromene derivatives are heterocycles with a wide range of biological properties. There is actually a need for safer synthesis of heterocycles, using for instance water as a solvent. High selectivity can also be achieved by addition of surface-active reagents to form micelles. Indeed, it is presumed that water facilitates organic reactions by the hydrophobic effect, enhanced hydrogen bonding in the transition state and cohesive energy density. Here, a simple aqueous-mediated protocol is developed for the quantitative synthesis of medicinally relevant pyrano[3,2-c]chromene derivatives by the tandem reaction of readily available reagents in cetyltrimethylammonium bromide micellar media. This new method is a modification of the three-component reaction involving Knoevenagel condensation, Michael addition and cyclization reaction. Yields of 3, 4-dihydropyrano[c]chromenes ranged from 85 to 99 % at room temperature.     

Upper trapezius fatigue in carpet weaving: the impact of a repetitive task cycle

Introduction. Shoulder disorders are one of the most prevalent musculoskeletal disorders among carpet weavers. The most important cause of these disorders is muscle fatigue. The aim of the present study is to investigate the effect of carpet weaving characteristics on upper trapezius (UTr) muscle fatigue during a task cycle. Method. In this cross-sectional study, 9 women and 3 men participated. During an 80-min cycle of carpet weaving, a times-series model was applied to assess electromyography amplitude and frequency changes. Result. According to the joint analysis of electromyogram spectrum and amplitude method, the participants experienced 0% force decrease, 0.9% recovery, 18% force increase and 72% fatigue in the left UTr. Furthermore, the rates of force decrease, recovery, force increase and fatigue in the right UTr were 18%, 18%, 18% and 45%, respectively. Fatigue in the right and the left UTr was reported to be the dominant state during one carpet weaving task cycle. Conclusion. Task cycle appears to have a significant impact on UTr fatigue in participants, and UTr fatigue can be considered a serious risk factor in shoulder musculoskeletal disorders. Hence, further studies should focus on better workstations and work–rest periods during various subtasks.     

Pesticide residues in fruits and vegetables from Pakistan: a review of the occurrence and associated human health risks

The main objective of the review is to document, assess and analyze the results of the previously reported data on levels of different pesticides in selected fruits and vegetables from Pakistan. The findings of the previous studies clearly indicated that more than 50 % of the samples were contaminated with organophosphate, pyrethroids and organochlorine pesticides. Many studies reported that among fresh fruits and vegetables tomato, apple, melon, mango, grapes, and plum crossed the FAO/WHO permissible limits for these contaminants residual levels. The comparison of other regions showed that observed levels were found above maximum residue limits (MRLs) in 50 % of the samples but were in agreement with the studies from neighboring countries like China and Bangladesh. Higher hazard risk index (HRI) values were calculated for dieldrin, methamidophos, o,p′-DDT, diazinon and p,p′-DDT in apple, mango, banana, melon, potato and onion. The review also highlights that data on pesticide residues in foodstuff is scarce which should be overcome by further extending studies from different areas of Pakistan. In order to ascertain the provision of food suitable for human consumption, it is imperative to monitor pesticides in food commodities by the country’s authorities and enforce guidelines based on permissible limits.