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Результаты 3671-3680 из 5,152
Multibiomarker biomonitoring approach using three bivalve species in the Ebro Delta (Catalonia, Spain) Полный текст
2018
Dallarés, Sara | Carrasco H., Noelia | Álvarez-Muñoz, Diana | Rambla-Alegre, Maria | Solé, Montserrat
Multibiomarker biomonitoring approach using three bivalve species in the Ebro Delta (Catalonia, Spain) Полный текст
2018
Dallarés, Sara | Carrasco H., Noelia | Álvarez-Muñoz, Diana | Rambla-Alegre, Maria | Solé, Montserrat
Bivalves have proved to be useful bioindicators for environmental pollution. In the present study, mussels (Mytilus galloprovincialis), cockles (Cerastoderma edule), and razor shells (Solen marginatus) were collected in the Ebro Delta, an extensive area devoted to rice farming and affected by pesticide pollution, from April to July, the heaviest rice field treatment period. Possible effects of pollution were assessed through biochemical markers (carboxylesterase (CE), antioxidant and neurotoxicity-related enzymes, and lipid peroxidation levels). Data on environmental variables, bivalve reproductive condition, and presence of organic pollutants, marine phycotoxins, pathogens, or histopathological conditions in bivalve’s tissues were also evaluated. Although the bioaccumulated pesticides did not explain the patterns observed for biochemical responses, the obtained results point to an effect of environmental pesticide pollution on enzymatic markers, with a prominent contribution of CE to such changes. Mussels and razor shells provided a more sensitive biochemical response to pollution than cockles. Environmental variables, bivalve reproductive condition, and marine phycotoxins did not seem to have a relevant effect on the biomarkers assessed.
Показать больше [+] Меньше [-]Multibiomarker biomonitoring approach using three bivalve species in the Ebro Delta (Catalonia, Spain) Полный текст
2018
Dallarés, Sara | Carrasco, Noèlia | Álvarez-Muñoz, Diana | Rambla-Alegre, Maria | Solé, Montserrat | Ministerio de Economía y Competitividad (España)
14 pages, 7 figures, 2 tables, supplementary material https://doi.org/10.1007/s11356-018-3614-6 | Bivalves have proved to be useful bioindicators for environmental pollution. In the present study, mussels (Mytilus galloprovincialis), cockles (Cerastoderma edule), and razor shells (Solen marginatus) were collected in the Ebro Delta, an extensive area devoted to rice farming and affected by pesticide pollution, from April to July, the heaviest rice field treatment period. Possible effects of pollution were assessed through biochemical markers (carboxylesterase (CE), antioxidant and neurotoxicity-related enzymes, and lipid peroxidation levels). Data on environmental variables, bivalve reproductive condition, and presence of organic pollutants, marine phycotoxins, pathogens, or histopathological conditions in bivalve’s tissues were also evaluated. Although the bioaccumulated pesticides did not explain the patterns observed for biochemical responses, the obtained results point to an effect of environmental pesticide pollution on enzymatic markers, with a prominent contribution of CE to such changes. Mussels and razor shells provided a more sensitive biochemical response to pollution than cockles. Environmental variables, bivalve reproductive condition, and marine phycotoxins did not seem to have a relevant effect on the biomarkers assessed | This work was financed by the Spanish Ministry of Economy, Industry and Competitiveness project AIMCOST (ref CGL2016-76332-R MINECO/FEDER/UE). It was also partially supported by the projects XENOMETABOLOMIC (ref CTM2015-73179-JIN AEI/FEDER/UE) and EMERGER (ref E-RTA2015-00004-00-00 INIA) | Peer Reviewed
Показать больше [+] Меньше [-]Environmentally benign nanometric neem-laced urea emulsion for controlling mosquito population in environment Полный текст
2018
Mishra, Prabhakar | Samuel, MerlynKeziah | Reddy, Ruchishya | Tyagi, BrijKishore | Mukherjee, Amitava | Chandrasekaran, Natarajan
The increasing risk of vector-borne diseases and the environmental pollution in the day-to-day life due to the usage of the conventional pesticides makes the role of nanotechnology to come into the action. The current study deals with one of the applications of nanotechnology through the formulation of neem urea nanoemulsion (NUNE). NUNE was formulated using neem oil, Tween 20, and urea using the microfluidization method. Prior to the development of nanoemulsion, the ratio of oil/surfactant/urea was optimized using the response surface modeling method. The mean droplet size of the nanoemulsion was found to be 19.3 ± 1.34 nm. The nanoemulsion was found to be stable for the period of 4 days in the field conditions which aids to its mosquitocidal activity. The nanoemulsion exhibited a potent ovicidal and larvicidal activity against A. aegypti and C. tritaeniorhynchus vectors. This result was corroborated with the histopathological analysis of the NUNE-treated larvae. Further, the effect of NUNE on the biochemical profile of the target host was assessed and was found to be efficacious compared to the bulk counterpart. The nanoemulsion was then checked for its biosafety towards the non-target species like plant beneficial bacterium (E. ludwigii), and phytotoxicity was assessed towards the paddy plant (O. sativa). Nanometric emulsion at the concentration used for the mosquitocidal application was found to be potentially safe towards the environment. Therefore, the nanometric neem-laced urea emulsion tends to be an efficient mosquito control agent with an environmentally benign property.
Показать больше [+] Меньше [-]A numerical study on the effect of various combustion bowl parameters on the performance, combustion, and emission behavior on a single cylinder diesel engine Полный текст
2018
Balasubramanian, Dhinesh | Sokkalingam Arumugam, Sabari Rajan | Subramani, Lingesan | Joshua Stephen Chellakumar, IsaacJoshuaRamesh Lalvani | Mani, Annamalai
A numerical study was carried out to study the effect of various combustion bowl parameters on the performance behavior, combustion characteristics, and emission magnitude on a single cylinder diesel engine. A base combustion bowl and 11 different combustion bowls were created by varying the aspect ratio, reentrancy ratio, and bore to bowl ratio. The study was carried out at engine rated speed and a full throttle performance condition, without altering the compression ratio. The results revealed that the combustion bowl parameters could have a huge impact on the performance behavior, combustion characteristics, and emission magnitude of the engine. The bowl parameters, namely throat diameter and toroidal radius, played a crucial role in determining the performance behavior of the combustion bowls. It was observed that the combustion bowl parameters, namely central pip distance, throat diameter, and bowl depth, also could have an impact on the combustion characteristics. And throat diameter and toroidal radius, central pip distance, and toroidal corner radius could have a consequent effect on the emission magnitude of the engine. Of the different combustion bowls tested, combustion bowl 4 was preferable to others owing to the superior performance of 3% of higher indicated mean effective pressure and lower fuel consumption. Interestingly, trade-off for NO ₓ emission was higher only by 2.85% compared with the base bowl. The sensitivity analysis proved that bowl depth, bowl diameter, toroidal radius, and throat diameter played a vital role in the fuel consumption parameter and emission characteristics even at the manufacturing tolerance variations.
Показать больше [+] Меньше [-]Comparison between snowmelt-runoff and rainfall-runoff nonpoint source pollution in a typical urban catchment in Beijing, China Полный текст
2018
Chen, Lei | Zhi, Xiaosha | Shen, Zhenyao | Dai, Ying | Aini, Guzhanuer
As a climate-driven event, nonpoint source (NPS) pollution is caused by rainfall- or snowmelt-runoff processes; however, few studies have compared the characteristics and mechanisms of these two kinds of NPS processes. In this study, three factors relating to urban NPS, including surface dust, snowmelt, and rainfall-runoff processes, were analyzed comprehensively by both field sampling and laboratory experiments. The seasonal variation and leaching characteristics of pollutants in surface dust were explored, and the runoff quality of snowmelt NPS and rainfall NPS were compared. The results indicated that dusts are the main sources of urban NPS and more pollutants are deposited in dust samples during winter and spring. However, pollutants in surface dust showed a low leaching ratio, which indicated most NPS pollutants would be carried as particulate forms. Compared to surface layer, underlying snow contained higher chemical oxygen demand, total suspended solids (TSS), Cu, Fe, Mn, and Pb concentrations, while the event mean concentration of most pollutants in snowmelt tended to be higher in roads. Moreover, the TSS and heavy metal content of snowmelt NPS was always higher than those of rainfall NPS, which indicated the importance of controlling snowmelt pollution for effective water quality management.
Показать больше [+] Меньше [-]Effect of amount and duration of waste green tea powder on the growth performance, carcass characteristics, blood parameters, and lipid metabolites of growing broilers Полный текст
2018
Liu, Wuyi | Rouzmehr, Fariba | Seidavi, Alireza
This study has evaluated the possible effect of waste powder of green tea (Camellia sinensis) in feed supplementation on the growth performance, carcass characteristics, blood parameters, and lipid metabolites of growing broilers (chicks) in both the amount and duration aspects of dietary additives during the finisher phases. In the experiment, growth performance, carcass characteristics, blood parameters, and lipid metabolites of broiler chicks have been fully recorded and explored. The diet of 271 day-old Ross 308 male broiler chicks has been supplemented with 0, 0.25, 0.50, 0.75, and 1.00% (w/w) green tea powder in addition to normal feeding additives. The experiment lasted for 21 and 42 days, respectively, for each value of the green tea supplement and for separate groups of animals. Broiler feed has been supplemented with different levels of green tea powder to assess the trial effect and potential beneficial dose on selected growth performance, carcass characteristics, and blood parameters of broiler chicks. Although there are almost no differences of broiler parameters and characteristics measured from one point of view of single treatment factor (amount or duration), against the control groups during the three trial periods, the overall effect of amount and duration of feeding green tea powder is positive on growth performance, carcass characteristics, blood parameters, and lipid metabolites of growing broilers, although there are nearly no differences in some broiler parameters and characteristics. However, there are a remarkable interactive effect of amount and duration of different feeding levels of green tea powder and obvious differences observed in all the parameters and characteristics of growing broilers. Especially, usage of feeding green tea powder largely decreased the abdominal fat content and some lipid metabolites, including VLDL cholesterol, LDL cholesterol, triglycerides, and AST of broiler chicks. While additional data are still needed to evaluate and analyze the optimum supplement feed doses, it can be concluded that dietary green tea is a positive feed supplementation to reduce abdominal fat and lipid metabolites and induce antioxidants.
Показать больше [+] Меньше [-]The severity factor as a useful tool for producing hydrochars and derived carbon materials Полный текст
2018
Jeder, Asma | Sanchez-Sanchez, Angela | Gadonneix, Philippe | Masson, Eric | Ouederni, Abdelmottaleb | Celzard, Alain | Fierro, Vanessa
The main purpose of this study was to understand the effect of time and temperature during the hydrothermal carbonisation (HTC) of olive stones (OS). For that purpose, the severity factor was introduced, by which the effect of the HTC conditions on the resultant products could be described. HTC was carried out at various temperatures (160, 180, 200, 220 and 240 °C) and times (3, 6, 12, 24 and 48 h) for producing 25 hydrochars. The yield to hydrochar varied from 70 to 50%. Hydrochars were all submitted to thermogravimetric and elemental analysis. The liquid fractions were also recovered and analysed in order to valorise OS as completely as possible. Thus, highly added-value products such as furfural and 5-hydroxymethylfurfural were detected. At the highest temperature and time, the hydrochar elemental composition was similar to that of lignite coals. Hydrochars were further carbonised at 900 °C, leading to materials with surface areas as high as 1200 m² g⁻¹ and with narrow pore size distributions centred on 0.5 nm. The severity factor allowed finding clear tendencies in the production of hydrochars and derived carbons in terms of yield, composition, and surface area, which would have been hardly analysed if the effects of temperature and time had to be considered separately. We proved that the severity factor, which use is quite uncommon in studies dealing with materials production, is a valuable tool for studying the effects of HTC experimental conditions.
Показать больше [+] Меньше [-]Assessing resident awareness on e-waste management in Bangalore, India: a preliminary case study Полный текст
2018
Awasthi, AbhishekKumar | Li, Jinhui
The generation of e-waste has increased significantly in India, and the informal recycling of e-waste has adverse effects on environment and public health. In this article, the E-waste management is evaluated in accordance from the resident’s awareness perspective in Bangalore city, India. The survey data revealed that about 58% male and 42% female responded and 35% of the participants belong to age range between 18 and 25 years. About 60% of respondent’s education level was either graduate or post graduate, 27% high school to higher school, 10% higher educated (> post graduate), and 3% primary to middle. Only 30% of the respondents were confident with e-waste rules and regulation, while 39% of the respondents were of very little information. Indian e-waste management has been improving for the last few years and it continues to develop. Therefore, the findings can be valuable for better understanding the resident’s awareness for e-waste management and also need to promote the environmentally sound management of e-waste in Bangalore, India.
Показать больше [+] Меньше [-]Fabrication of highly effective mosquito nanolarvicides using an Asian plant of ethno-pharmacological interest, Priyangu (Aglaia elaeagnoidea): toxicity on non-target mosquito natural enemies Полный текст
2018
Benelli, Giovanni | Govindarajan, Marimuthu | Senthilmurugan, Sengamalai | Vijayan, Periasamy | Kadaikunnan, Shine | Alharbi, NaiyfS. | Khaled, JamalM.
Mosquitoes threaten the lives of humans, livestock, pets and wildlife around the globe, due to their ability to vector devastating diseases. Aglaia elaeagnoidea, commonly known as Priyangu, is widely employed in Asian traditional medicine and pest control. Medicinal activities include anti-inflammatory, analgesic, anticancer, and anesthetic actions. Flavaglines, six cyclopenta[b]benzofurans, a cyclopenta[bc]benzopyran, a benzo[b]oxepine, and an aromatic butyrolactone showed antifungal properties, and aglaroxin A and rocaglamide were effective to control moth pests. Here, we determined the larvicidal action of A. elaeagnoidea leaf aqueous extract. Furthermore, we focused on Priyangu-mediated synthesis of Ag nanoparticles toxic to Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi. The plant extract and the nanolarvicide were tested on three mosquito vectors, following the WHO protocol, as well as on three non-target mosquito predators. Priyangu-synthesized Ag nanoparticles were characterized by spectroscopic (UV, FTIR, XRD, and EDX) and microscopic (AFM, SEM, and TEM) analyses. Priyangu extract toxicity was moderate on Cx. quinquefasciatus (LC₅₀ 246.43; LC₉₀ 462.09 μg/mL), Ae. aegypti (LC₅₀ 229.79; LC₉₀ 442.71 μg/mL), and An. stephensi (LC₅₀ 207.06; LC₉₀ 408.46 μg/mL), respectively, while Priyangu-synthesized Ag nanoparticles were highly toxic to Cx. quinquefasciatus (LC₅₀ 24.91; LC₉₀ 45.96 μg/mL), Ae. aegypti (LC₅₀ 22.80; LC₉₀ 43.23 μg/mL), and An. stephensi (LC₅₀ 20.66; LC₉₀ 39.94 μg/mL), respectively. Priyangu extract and Ag nanoparticles were found safer to non-target larvivorous fishes, backswimmers, and waterbugs, with LC₅₀ ranging from 1247 to 37,254.45 μg/mL, if compared to target pests. Overall, the current research represents a modern approach integrating traditional botanical pesticides and nanotechnology to the control of larval populations of mosquito vectors, with negligible toxicity against non-target including larvivorous fishes, backswimmers, and waterbugs.
Показать больше [+] Меньше [-]Financial development, income inequality, and CO2 emissions in Asian countries using STIRPAT model Полный текст
2018
Khan, AbdulQayyum | Saleem, Naima | Fatima, SyedaTamkeen
The main purpose of this paper is to find the effects of financial development, income inequality, energy usage, and per capita GDP on carbon dioxide (CO₂) emissions as well the environmental Kuznets curve (EKC) for the three developing Asian countries—Bangladesh, India, and Pakistan. Panel data during the period 1980–2014 and the Stochastic Impacts by Regression on Population, Affluence, and Technology model with fully modified ordinary least squares (FMOLS) are employed for empirical investigation. The results show that financial development has a significant negative relationship with CO₂ emission in the three selected Asian countries with the exception of India. The results further reveal that income inequality in Pakistan and India reduce CO₂ emission, while the result for Bangladesh is opposite. Likewise, energy usage has a significant positive effect on CO₂ emission in Bangladesh, Pakistan, and India. Our empirical analysis based on long-run and short-run elasticity appraisal suggests the validation of the EKC in Pakistan and India. The study findings recommend an important policy insinuation. The study suggests introducing a motivational campaign for the inhabitant towards utilization of high-efficiency electrical appliances, constructing mutual cooperation for economic development rather involve in winning development race, and introducing effective pollution absorption measures along with big projects.
Показать больше [+] Меньше [-]Investigations of microbial degradation of polycyclic aromatic hydrocarbons based on 13C-labeled phenanthrene in a soil co-contaminated with trace elements using a plant assisted approach Полный текст
2018
Wawra, Anna | Friesl-Hanl, Wolfgang | Jäger, Anna | Puschenreiter, Markus | Soja, Gerhard | Reichenauer, Thomas | Watzinger, Andrea
Co-contaminations of soils with organic and inorganic pollutants are a frequent environmental problem. Due to their toxicity and recalcitrance, the heterogeneous pollutants may persist in soil. The hypothesis of this study was that degradation of polycyclic aromatic hydrocarbons (PAHs) is enhanced if heavy metals in soil are immobilized and their bioavailability reduced. For metal immobilization and enhanced biodegradation, distinct mineral and organic soil amendments (iron oxides, gravel sludge, biochar) were deployed in an incubation batch experiment. The second part of the experiment consisted of a greenhouse pot experiment applying fast-growing and pollution-tolerant woody plants (willow and black locust). Soil amendments initially immobilized NH₄NO₃-extractable zinc, cadmium, and lead; after 100 days of incubation, soil amendments showed reductions only for cadmium and a tendency to enhance arsenic mobility. In order to monitor the remediation success, a ¹³C-phenanthrene (PHE) label was applied. ¹³C-phospholipid fatty acid analysis (¹³C-PLFA) further enabled the identification of PHE-degrading soil microorganisms. Both experiments exhibited a similar PLFA profile. Gram-negative bacteria (esp. cy17:0, 16:1ω7 + 6, 18:1ω7c) were the most significant microbial group taking up ¹³C-PHE. Plants effectively increased the label uptake by gram-positive bacteria and increased the biomass of the fungal biomarker, although their contribution to the degradation process was minor. Plants tended to prolong PAH dissipation in soil; at the end of the experiment, however, all treatments showed equally low total PAH concentrations in soil. While black locust plants tended not to take up potentially toxic trace elements, willows accumulated them in their leaves. The results of this study show that the chosen treatments did not enhance the remediation of the experimental soil.
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