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The penetration of sustainable technologies in electricity generation is low until now in Greece. However, the recent adoption of legislative rules towards the effective operation of liberalized markets, as well as the increased impact of climate change on the electricity sector towards the period 2008–2012, bring out these technologies as key means for establishing conditions of security, stability and environmental protection. The objective of this paper is to put on the map the sustainable technologies for electricity generation in Greece through the formulation of a collective interactive supportive framework, using an existing multi-criteria decision-making (MCDM) method to elaborate more realistic and transparent outcomes. The approach was implemented under the umbrella of the national Foresight Programme, to assist policy making for sustainable electricity generation technologies.  相似文献   
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Environmental Science and Pollution Research - The outbreak of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected the entire world with its infectious spread and...  相似文献   
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The aim of the present study was to appraise the levels of heavy metal contamination (Zn and Pb) in sediment of the Langat River (Selangor, Malaysia). Samples were collected randomly from 15 sampling stations located along the Langat River. The parameters measured were pH, redox potential, salinity, electrical conductivity, loss of ignition, cation exchanges capacity (Na, Mg, Ca, K), and metal ions (Zn and Pb). The geo-accumulation index (I geo) and contamination factor (C f) were applied to determine and classify the magnitude of heavy metal pollution in this urban river sediment. Results revealed that the I geo of Pb indicated unpolluted to moderately polluted sediment at most of the sampling stations, whereas Zn was considered to be within background concentration. The I geo results were refined by the C f values, which showed Pb with very high C f at 12 stations. Zinc, on the other hand, had low to moderate C f values. These findings indicated that the sediment of the Langat River is severely polluted with Pb. The Zn concentration at most sampling points was well below most sediment quality guidelines. However, 40% of the sampling points were found to have a Pb concentration higher than the consensus-based probable effect concentration of 128 mg/kg (concentrations above this value are likely to cause harmful effects). This result not only highlights the severity of Pb pollution in the sediment of the Langat River, but also the potential risk it poses to the environment.  相似文献   
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Millions of people in some of the poorest regions of the world are exposed to high levels of arsenic through drinking contaminated water. It has been reported that development of cancer caused by arsenic exposure in such populations is dependent on dietary and nutritional factors which can modulate arsenic metabolism. Many people in arsenic exposed regions of Bangladesh and India practice fasting for at least one month every year when they refrain from consumption of food and fluid during daylight hours. How such practices may modulate arsenic metabolism has not been previously investigated. This study investigated this issue by determining total arsenic and its species in urine samples from a group of 29 unexposed volunteers at the beginning of the fasting and at the end of approximately 12 h of fasting period. Inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC) coupled with ICP-MS was used to measure the total arsenic and arsenic speciation in the urine samples, respectively. The mean total levels of arsenic at the beginning of fasting (18.3 microg g(-1) creatinine) and at the end of approximately 12 h of fasting (17.7 microg g(-1) creatinine) did not differ significantly (p > 0.05). However, the percentages of urinary arsenic as the methylated arsenic species methylarsonate (MA) were found to be significantly different (p < 0.05) and this species was observed more frequently at the end of fasting, although its overall concentration was similar. There were no significant differences (p > 0.05) in both the concentrations and percentages of other urinary arsenic species detected, namely arsenobetaine (AB) and dimethylarsinate (DMA). Arsenite (As(III)) and arsenate (As(V)) were also analyzed, but were not detected. We conclude that fasting for a period of 12 h results in a significant increase in the percentage of urinary arsenic as MA, and its frequency of detection in the volunteers at the end of the fasting period is almost nine fold higher. This suggests that metabolism of arsenic is altered by fasting.  相似文献   
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Five week-old mice were divided into a vehicle control group, and groups exposed to ZnO nanoparticles at low (0.5 g/kg), middle (1 g/kg), high (3 g/kg), and exceptionally high-dose (5 g/kg). After the first, second, third, and fourth weeks’ of exposure, blood biochemistry, histopathology, and electron microscopic ultrastructural changes in liver, kidney and spleen were investigated. Increased alkaline phosphatase activities were observed in all treated mice being statistically significant at higher dose. No changes were observed in the serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, creatinine, blood urea nitrogen, and lipid levels. During the first and second weeks of the treatment, effects on the cytoarchitecture of liver, kidney, and spleen were not perceived while during the third and fouth weeks of treatment sporadic mild effects were seen. Ultrastructural electron microscopic changes in liver, kidney, and spleen were not observed for the low-dose group on the first, second, third, and fourth weeks, suggesting that exposure to ZnO nanoparticles at low dose is safe. Long-term (i.e., more than 28 days) exposure to the exceptionally high-dose resulted in sporadic changes in nuclear chromatin condensation, irregular nuclear membrane, polymorphic mitochondria, mitochondrial swelling, and vacuolation. ZnO nanoparticles could be well tolerated and no death occurred in any group of treated mice.  相似文献   
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The changing climate scenarios harshen the biotic stresses including boosting up the population of insect/pest and disease, uplifting weed growth, declining soil beneficial microbes, threaten pollinator, and boosting up abiotic stresses including harsh drought/waterlogging, extremisms in temperature, salinity/alkalinity, abrupt rainfall pattern)) and ulitamtely  affect the plant in multiple ways. This nexus review paper will cover four significant points viz (1) the possible impacts of climate change; as the world already facing the problem of food security, in such crucial period, climatic change severely affects all four dimensions of food security (from production to consumption) and will lead to malnutrition/malnourishment faced by low-income peoples. (2) How some major crops (wheat, cotton, rice, maize, and sugarcane) are affected by stress and their consequent loss. (3) How to develop a strategic work to limit crucial factors, like their significant role in climate-smart breeding, developing resilience to stresses, and idiotypic breeding. Additionally, there is an essence of improving food security, as much of our food is wasted before consumption for instance post-harvest losses. (4) Role of biotechnology and genetic engineering in adaptive introgression of the gene or developing plant transgenic against pests. As millions of dollars are invested in innovation and research to cope with future climate change stresses on a plant, hence community base adaptation of innovation is also considered an important factor in crop improvements. Because of such crucial predictions about the future impacts of climate change on agriculture, we must adopt measures to evolve crop.

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We demonstrate that the non-living, dried roots of the water hyacinth plant [Eichhornia crassipes(Mart.) Solms] can rapidly remove arsenic from water. Atomic absorption spectrometry was used to demonstrate that more than 93% of arsenite (As(iii)) and 95% of arsenate (As(v)) were removed from a solution containing 200 microg As l(-1) within 60 minutes of exposure to a powder produced from dried roots. No difference in removal efficiency was observed between the two oxidation states of As studied. The amount of arsenic remaining in solution was found to be less than 10 microg l(-1) which is the WHO guideline limit value for As in drinking water. The presence of arsenic in drinking water in a number of countries in the developing world has been found to be much higher than the WHO level, affecting the health of millions of people. In this paper, we show that a biomaterial produced from dried water hyacinth roots, a plant that is found in abundant supply in many parts of the world, can provide a simple, effective and yet cheap method for removing arsenic from contaminated water.  相似文献   
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