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Long-term changes in nitrogen and phosphorus emission into the Vistula and Oder catchments (Poland)—modeling (MONERIS) studies Texto completo
2018
Pastuszak, Marianna | Kowalkowski, Tomasz | Kopiński, Jerzy | Doroszewski, Andrzej | Jurga, Beata | Buszewski, Boguslaw
Modeling (MONERIS) studies allowed calculation of nitrogen (N) and phosphorus (P) emission into the Vistula and Oder basins (Poland), and facilitated estimation of N and P retention in these catchments in 1995–2015. In the discussion of results, data of other authors were used in order to get an insight into N (1880–2015) and P emission (1955–2015) into the Oder basin. Population growth and agricultural intensification were responsible for respective 5.3-fold and 3.5-fold increase in N and P emission into the Oder basin, with the maximum (135,000 tons N year⁻¹; 14,000 tons P year⁻¹) observed at the turn of the 1980s/1990s. Pro-ecological activities during the economic transition period (since 1989) covered various sectors of the economy including agriculture, environmental protection related to, e.g., construction of a large number of waste water treatment plants (WWTPs). Consequently, in 1985–2015, the emission into the Oder basin decreased from the abovementioned maxima to 94,000 tons N year⁻¹ and to 5000 tons P year⁻¹, whereas in 1995–2015, the emission into the Vistula basin decreased from 170,000 to 140,000 tons N year⁻¹ and from 14,200 to 10,600 tons P year⁻¹. In 1995–2015, groundwater, tile drainage, and WWTPs played a key role in N emission, while erosion, overland flow, WWTPs, and urban areas played a predominant role in P emission. The relative shares of nutrient emission pathways in overall N and P emission were considerably changing over time. Extreme weather conditions have a great impact on increased (floods) or decreased (droughts) nutrient emission; particularly, N emission is susceptible to variable weather conditions. In total, approximately 91,000 tons of N and 7600 tons of P were retained annually in the river basins.
Mostrar más [+] Menos [-]Highly cited articles in wind tunnel-related research: a bibliometric analysis Texto completo
2018
Mo, Ziwei | Fu, Hui-Zhen | Ho, Yuh-Shan
Wind tunnels have been widely employed in aerodynamic research. To characterize the high impact research, a bibliometric analysis was conducted on highly cited articles related to wind tunnel based on the Science Citation Index Expanded (SCI-EXPANDED) database from 1900 to 2014. Articles with at least 100 citations from the Web of Science Core Collection were selected and analyzed in terms of publication years, authors, institutions, countries/territories, journals, Web of Science categories, and citation life cycles. The results show that a total of 77 highly cited articles in 37 journals were published between 1959 and 2008. Journal of Fluid Mechanics published the most of highly cited articles. The USA was the most productive country and most frequent partner of internationally collaboration. The prolific institutions were mainly located in the USA and UK. The authors who were both first author and corresponding author published 88% of the articles. The Y index was also deployed to evaluate the publication characteristics of authors. Moreover, the articles with high citations in both history and the latest year with their citation life cycles were examined to provide insights for high impact research. The highly cited articles were almost earliest wind tunnel experimental data and reports on their own research specialty, and thus attracted high citations. It was revealed that classic works of wind tunnel research was frequently occurred in 1990s but much less in 2000s, probably due to the development of numerical models of computational fluid dynamic (CFD) in recent decades.
Mostrar más [+] Menos [-]Effects of monoterpenes on mortality, growth, fecundity, and ovarian development of Bactrocera zonata (Saunders) (Diptera: Tephritidae) Texto completo
2018
El-Minshawy, AbdelazizM. | Abdelgaleil, SamirA. M. | Gadelhak, GadelhakG. | AL-Eryan, MohamedA. | Rabab, RafiaaA.
The peach fruit fly (PFF), Bactrocera zonata, is a serious insect pest infesting fruits and vegetables. The insecticidal activity of three monoterpenes, namely, (R)-camphor, (R)-carvone, and (1R,2S,5R)-menthol, was evaluated on the second-instar larvae of B. zonata. In addition, the latent effects of monoterpenes on pupation, adult emergence, deformation, oviposition, adult longevity, and ovarian development were also examined. The three tested monoterpenes showed pronounced insecticidal activity against B. zonata larvae with (R)-carvone being the most potent toxicant. When the second-instar larvae of B. zonata were treated with monoterpenes at concentrations of 20, 50, and 70 mg/kg for 72 h, significant reduction in pupation and adult emergence was observed. The three monoterpenes caused complete suppression of adult emergence at 100 mg/kg. Moreover, monoterpenes induced complete inhibition of egg deposition at all tested concentrations. Some adult deformations were also noticed at 20, 50, and 70 mg/kg. However, (R)-carvone was more effective than (1R,2S,5R)-menthol and (R)-camphor on the examined biological parameters. On the other hand, histological examination of the ovaries of emerged females from larvae that fed on diet treated with (R)-carvone, (1R,2S,5R)-menthol, and (R)-camphor at 20 and 50 mg/L indicated that both concentrations caused retardation in the development of ovarioles. It is clear that all the egg chambers are empty; the germarium region is constricted at base due to the failure of oocyte formation. Many vacant spaces were present between ovarioles.
Mostrar más [+] Menos [-]Removal of micro-pollutants from urban wastewater by constructed wetlands with Phragmites australis and Salix matsudana Texto completo
2018
Francini, Alessandra | Mariotti, Lorenzo | Di Gregorio, Simona | Sebastiani, L. | Andreucci, Andrea
This study assessed the ability to remove micro-pollutants from wastewater using herbaceous species (Phragmites australis L.) and trees (Salix matsudana Koidz.) in constructed wetland (CW) systems. The targets of the study were as follows: (i) pharmaceuticals like diclofenac, ketoprofen, and atenolol; (ii) 4-n-NP (4-n-nonylphenol) and the ethoxylated derivatives monoethoxylated nonylphenol (NP₁EO) and diethoxylated nonylphenol (NP₂EO); (iii) triclosan, a bactericide used in personal care products. The 12 CW systems, filled with clay and gravel, were irrigated with wastewater from municipal area of Pagnana (Tuscany, Italy) and influent and effluent water samples analyzed periodically by gas chromatography-mass spectrometry (GC-MS/MS). The removal efficiency of CWs planted with willow and common red ranged from 8.4 up to 100%, with the higher removal efficiency for triclosan. On the contrary, the removal efficiency of NPs and NPEOs appears lower than pharmaceuticals. Data demonstrated that P. australis efficiently removed NP, diclofenac, and atenolol, while S. matsudana preferentially removed NP₁EO, NP₂EO, ketoprofene, and triclosan. A specific selection of plants used in CWs could be exploited for the removal of specific xenobiotics from wastewater.
Mostrar más [+] Menos [-]Effect of long-term exposure to ambient particulate matter on prevalence of type 2 diabetes and hypertension in Iranian adults: an ecologic study Texto completo
2018
Hassanvand, MohammadSadegh | Naddafi, Kazem | Malek, Mojtaba | Valojerdi, AmenehEbrahim | Mirzadeh, Mohanad | Samavat, Tahereh | Hezaveh, AlirezaMahdavi | Hodjatzadeh, Alieh | Khamseh, MohammadEbrahim
Air pollution is considered as an environmental risk to health worldwide. Current evidence is mostly from Western populations exposed to lower levels of pollutants. This study was to explore the association of type 2 diabetes (T2D) and hypertension prevalence with exposure to high levels of air pollution in Iranian adults. The air pollution data were obtained from the air quality monitoring stations of five large cities in Iran from 2006 to 2011. The air quality monitoring stations could only detect ambient particulate matter_10 (PM₁₀) during the study period; therefore, the average PM₁₀ concentration was considered for comparison. We grouped the cities as group 1 (Tehran, Shiraz) with PM₁₀ concentration < 100 μg/m³, and group 2 (Kermanshah, Ahwaz, Esfahan) with PM₁₀ concentration > 100 μg/m³. Data from the Surveillance of Risk Factors of Non-Communicable Disease (SuRFNCD) study were used to calculate the prevalence of T2D and hypertension. We assessed the association between air pollution and the prevalence of T2D using logistic regression models. Odds ratios (ORs) with 95% CI for each outcome were calculated after adjusting for age, sex, BMI, physical activity, and other covariates. The 5-year average of PM₁₀ concentration was higher in group 2 (120.15 ± 6.81 μg/m³) compared to group 1 (83.95 ± 7.81 μg/m³). The prevalence of T2D in group 2 was 13.8%, while it was 10.7% in group 1 (p = 0.01), OR = 1.32 (95% CI 1.03–1.69). Similarly, hypertension was more prevalent in group 2 (15.7 vs. 11.9%, p = 0.005, OR = 1.55, 95% CI 1.20–1.99). PM₁₀ is associated with higher prevalence of T2D and hypertension in Iranian adults.
Mostrar más [+] Menos [-]Impact of economic growth, nonrenewable and renewable energy consumption, and urbanization on carbon emissions in Sub-Saharan Africa Texto completo
2018
Hanif, Imran
The present study explores the impact of economic growth; urban expansion; and consumption of fossil fuels, solid fuels, and renewable energy on environmental degradation in developing economies of Sub-Saharan Africa. To demonstrate its findings in detail, the study adopts a system generalized method of moment (GMM) on a panel of 34 emerging economies for the period from 1995 to 2015. The results describe that the consumption of fossil and solid fuels for cooking and expansion of urban areas are significantly contributing to carbon dioxide emissions, on one end, and stimulating air pollution, on the other. The results also exhibit an inverted U-shape relationship between per capita economic growth and carbon emissions. This relation confirms the existence of an environmental Kuznets curve (EKC) in middle- and low-income economies of Sub-Saharan Africa. Furthermore, the findings reveal that the use of renewable energy alternatives improves air quality by controlling carbon emissions and lowering the direct interaction of households with toxic gases. Thus, the use of renewable energy alternatives helps the economies to achieve sustainable development targets.
Mostrar más [+] Menos [-]Deltamethrin-induced nuclear erythrocyte alteration and damage to the gills and liver of Colossoma macropomum Texto completo
2018
Cunha, Fernanda dos Santos | Sousa, Natalino da Costa | Santos, Rudã Fernandes Brandão | Meneses, Juliana Oliveira | do Couto, Márcia Valéria Silva | de Almeida, Fabrício Tavares Cunha | de Sena Filho, José Guedes | Carneiro, Paulo César Falanghe | Maria, Alexandre Nizio | Fujimoto, Rodrigo Yudi
Deltamethrin is one of the most commonly used pyrethroids in the world, and it has a high toxic potential, mainly on aquatic organism. Thus, the purpose of this study was to evaluate LC₅₀ values of deltamethrin on tambaqui (Colossoma macropomum) fingerlings and to investigate genotoxic effects and histopathological responses. Fish were exposed to different concentrations of deltamethrin (0, 6.16 × 10⁻³; 6.44 × 10⁻²; 1.34 × 10⁻¹, and 1.93 × 10⁻¹ mg L⁻¹) for 96 h. In addition, a genotoxicity analysis was carried out on peripheral blood erythrocytes and histopathological changes were classified by the severity degree of damage and organ functioning. The 96 h LC₅₀ value for tambaqui was estimated at 5.56 × 10⁻² mg L⁻¹ using a static test system. Nuclear abnormalities in exposed fish included micronuclei, blebbed, notched, 8-shaped, and binucleated nuclei forms. Deltamethrin significantly induced a notched nucleus compared to other abnormalities. A histopathological examination showed hepatic lesions and gill damage. Deltamethrin was found to be highly toxic; it induced genotoxicity and caused liver and gill inflammation in tambaqui.
Mostrar más [+] Menos [-]Non-point source pollution of glyphosate and AMPA in a rural basin from the southeast Pampas, Argentina Texto completo
2018
Okada, Elena | Pérez, Débora | De Gerónimo, Eduardo | Aparicio, Virginia | Massone, Héctor | Costa, José Luis
We measured the occurrence and seasonal variations of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in different environmental compartments within the limits of an agricultural basin. This topic is of high relevance since glyphosate is the most applied pesticide in agricultural systems worldwide. We were able to quantify the seasonal variations of glyphosate that result mainly from endo-drift inputs, that is, from direct spraying either onto genetically modified (GM) crops (i.e., soybean and maize) or onto weeds in no-till practices. We found that both glyphosate and AMPA accumulate in soil, but the metabolite accumulates to a greater extent due to its higher persistence. Knowing that glyphosate and AMPA were present in soils (> 93% of detection for both compounds), we aimed to study the dispersion to other environmental compartments (surface water, stream sediments, and groundwater), in order to establish the degree of non-point source pollution. Also, we assessed the relationship between the water-table depth and glyphosate and AMPA levels in groundwater. All of the studied compartments had variable levels of glyphosate and AMPA. The highest frequency of detections was found in the stream sediments samples (glyphosate 95%, AMPA 100%), followed by surface water (glyphosate 28%, AMPA 50%) and then groundwater (glyphosate 24%, AMPA 33%). Despite glyphosate being considered a molecule with low vertical mobility in soils, we found that its detection in groundwater was strongly associated with the month where glyphosate concentration in soil was the highest. However, we did not find a direct relation between groundwater table depth and glyphosate or AMPA detections. This is the first simultaneous study of glyphosate and AMPA seasonal variations in soil, groundwater, surface water, and sediments within a rural basin.
Mostrar más [+] Menos [-]PAMAM templated N,Pt co-doped TiO2 for visible light photodegradation of brilliant black Texto completo
2018
Nzaba, Sarre Kadia Myra | Ntsendwana, Bulelwa | Mamba, B. B. (Bhekie Brilliance) | Kuvarega, Alex Tawanda
This study examined the photocatalytic degradation of an azo dye brilliant black (BB) using non-metal/metal co-doped TiO₂. N,Pt co-doped TiO₂ photocatalysts were prepared by a modified sol-gel method using amine-terminated polyamidoamine dendrimer generation 0 (PG0) as a template and source of nitrogen. Structural, morphological, and textural properties were evaluated using scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy (SEM/EDX), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR), Raman spectroscopy (RS), photoluminescence (PL) and ultra-violet/visible spectroscopy (UV-Vis). The synthesized photocatalysts exhibited lower band gap energies as compared to the Degussa P-25, revealing a red shift in band gap towards the visible light absorption region. Photocatalytic activity of N,Pt co-doped TiO₂ was measured by the reaction of photocatalytic degradation of BB dye. Enhanced photodegradation efficiency of BB was achieved after 180-min reaction time with an initial concentration of 50 ppm. This was attributed to the rod-like shape of the materials, larger surface area, and enhanced absorption of visible light induced by N,Pt co-doping. The N,Pt co-doped TiO₂ also exhibited pseudo-first-order kinetic behavior with half-life and rate constant of 0.37 and 0.01984 min⁻¹, respectively. The mechanism of the photodegradation of BB under the visible light irradiation was proposed. The obtained results prove that co-doping of TiO₂ with N and Pt contributed to the enhanced photocatalytic performances of TiO₂ for visible light-induced photodegradation of organic contaminants for environmental remediation. Therefore, this work provides a new approach to the synthesis of PAMAM templated N,Pt co-doped TiO₂ for visible light photodegradation of brilliant black.
Mostrar más [+] Menos [-]Interaction of 24-epibrassinolide and salicylic acid regulates pigment contents, antioxidative defense responses, and gene expression in Brassica juncea L. seedlings under Pb stress Texto completo
2018
Kohli, Sukhmeen Kaur | Handa, Neha | Sharma, Anket | Gautam, Vandana | Arora, Saroj | Bhardwaj, Renu | Wijaya, Leonard | Alyemeni, Mohammed Nasser | Ahmad, Parvaiz
Lead (Pb) is considered one the most hazardous pollutant, and its accumulation in soil and plants is of prime concern. To understand the role of plant hormones in combating heavy metal stress, the present study was planned to assess the interactive effects of 24-epibrassinolide (EBL) (10⁻⁷ M) and salicylic acid (SA) (1 mM) in regulating growth, pigment contents, antioxidative defense response, and gene expression in Brassica juncea L. seedlings exposed to different concentrations of Pb metal (0.25, 0.50, and 0.75 mM). Reduction in root and shoot lengths, chlorophyll and carotenoid content, and non-enzymatic antioxidants like glutathione, ascorbic acid, and tocopherol in response to Pb toxicity was observed. The enzymatic antioxidants such as guaiacol peroxidase (POD), ascorbate peroxidase (APOX), glutathione peroxidase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate redductase (MDHAR), glutathione-S-transferease (GST), and glutathione peroxidase (GPOX) were lowered in response to Pb treatments. Other antioxidative enzymes including superoxide dismutase (SOD), catalase (CAT), and polyphenol oxidase (PPO) enhanced under metal stress. Co-application of EBL + SA to 0.75 mM Pb-treated seedlings resulted in improvement of root and shoot lengths, chlorophyll, and carotenoid contents. Similarly, glutathione, ascorbic acid, and tocopherol contents were also elevated. Enzymatic antioxidants were also significantly enhanced in response to pre-sowing combined treatment of both hormones. Gene expression analysis suggested elevation in expression of CAT, POD, GR, DHAR, and GST genes by application of EBL. Our results reveal that Pb metal toxicity caused adverse impact on B. juncea L. seedlings, but pre-soaking treatment with EBL and SA individually and in combination help seedlings to counter the ill effects of Pb by improving growth, contents of pigment, and modulation of antioxidative defense system. The combined application of EBL and SA was found to be more effective in ameliorating Pb stress as compared to their individual treatments.
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