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Air pollution emission effects of changes in transport supply: the case of Bogotá, Colombia Полный текст
2020
Mangones, Sonia C. | Jaramillo, Paulina | Rojas, Nestor Y. | Fischbeck, Paul
Transportation policy and planning decisions, including decisions on new infrastructure and public transport improvements, affect local and global environmental conditions. This work studies the effect of increased road capacity on traffic-related emissions in Bogotá using a tool that couples a transportation model with emission factors from COPERT IV. We followed a parametric approach varying transport supply and demand, comparing three scenarios: a baseline scenario that represents the transportation system in Bogota in 2015; scenario 1 incorporates five highway capacity-enhancement projects in Bogotá and assumes insensitive travel demand; scenario 2 incorporates the new highway projects but assumes a demand increase of 13% in vehicle trips with private cars. Results include daily and annual values of traffic-related emissions of five air pollutant criteria: CO, NOₓ, PM₁₀, SO₂, and VOC for the baseline scenario, scenario 1, and scenario 2. We found a reduction in emissions after adding highway capacity and assuming inelastic demand (scenario 1). Scenario 1 results in a 15% reduction in PM₁₀ emissions and a 10% reduction in NOₓ emissions. In contrast, results for scenario 2 suggest increased emissions for all air pollutant criteria (e.g., VOC and CO emissions increase by 21% and 22% compared with the baseline scenario). Therefore, new traffic demand would eliminate the emission savings observed in scenario 1 and could potentially further degrade air quality in Bogotá. While an exact estimate of induced demand that may result from highway expansion in Bogotá is not available, this analysis highlights that such projects could lead to an increase in emissions unless there is a combined effort to managing demand of private vehicle trips.
Показать больше [+] Меньше [-]Effects of low concentrations of deltamethrin are dependent on developmental stages and sexes in the pest moth Spodoptera littoralis Полный текст
2020
Malbert-Colas, Aude | Drozdz, Thomas | Massot, Manuel | Bagni, Thibaut | Chertemps, Thomas | Maria, Annick | Maïbèche, Martine | Siaussat, David
Effects of low concentrations of deltamethrin are dependent on developmental stages and sexes in the pest moth Spodoptera littoralis Полный текст
2020
Malbert-Colas, Aude | Drozdz, Thomas | Massot, Manuel | Bagni, Thibaut | Chertemps, Thomas | Maria, Annick | Maïbèche, Martine | Siaussat, David
Effects of low concentrations of pesticides, with no or moderate mortality of targeted species, are poorly studied even though these low concentrations are common under natural conditions. Studying their effects is critical because they can induce positive hormetic responses, possibly leading to greater pest multiplication and promoting the evolution of pest resistance. Here, we investigated the responses of the pest moth Spodoptera littoralis to low concentrations of deltamethrin, and tested for variation in effects of the pesticide between developmental stages and sexes. Indeed, we show that a given concentration of deltamethrin has different effects between stages, and even between sexes. Two experimental concentrations led to very high mortality early in S. littoralis development (4th larval instar), but only to low mortality rates in adults. Moreover, our highest experimental concentration had only detrimental effects in adult females, but improved the reproductive success of adult males. Model projections showed that the lethality from treatments at the 4th larval instar was the predominant effect. Because of the high multiplication rate of S. littoralis, it was also found that treatments with very similar effects on larval mortality can lead to either population extinction or rapid pest resurgence.
Показать больше [+] Меньше [-]Effects of low concentrations of deltamethrin are dependent on developmental stages and sexes in the pest moth Spodoptera littoralis Полный текст
2020
Malbert-Colas, Aude | Drozdz, Thomas | Massot, Manuel | Bagni, Thibaut | Chertemps, Thomas | Maria, Annick | Maïbèche, Martine | Siaussat, David | Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris) ; Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | Effects of low concentrations of pesticides, with no or moderate mortality of targeted species, are poorly studied even though these low concentrations are common under natural conditions. Studying their effects is critical because they can induce positive hormetic responses, possibly leading to greater pest multiplication and promoting the evolution of pest resistance. Here, we investigated the responses of the pest moth Spodoptera littoralis to low concentrations of deltamethrin, and tested for variation in effects of the pesticide between developmental stages and sexes. Indeed, we show that a given concentration of deltamethrin has different effects between stages, and even between sexes. Two experimental concentrations led to very high mortality early in S. littoralis development (4th larval instar), but only to low mortality rates in adults. Moreover, our highest experimental concentration had only detrimental effects in adult females, but improved the reproductive success of adult males. Model projections showed that the lethality from treatments at the 4th larval instar was the predominant effect. Because of the high multiplication rate of S. littoralis, it was also found that treatments with very similar effects on larval mortality can lead to either population extinction or rapid pest resurgence.
Показать больше [+] Меньше [-]A kind of NiO nanofilm photocatalyst supported on nano-PAA substrate for efficient degradation of organic dye wastewater Полный текст
2020
Huang, Yifei | Zhou, Yukun | Wang, Kaige
Dye wastewater has been becoming the focus of environmental protection and scientific research because of its serious harm to the environment and living organisms. A supported nano-porous anode alumina-NiO (nano-PAA-NiO) photocatalyst was prepared by calcining nano-PAA-NiCl₂ composite which was grown with a self-organization method. Its morphology and composition were investigated by means of SEM, EDS, and XRD. The specific surface area of nano-PAA-NiO was characterized with the N₂ adsorption and desorption isotherms. The band gap was calculated to be 3.0 eV with the UV–Vis absorption spectra. The species and optical properties of nano-PAA-NiO were investigated by FT-IR spectra and photoluminescence spectra. With the nano-PAA-NiO photocatalyst, the degradation rates of methyl orange (MO) were 94.3% under the optimum conditions, and it could reach 82% when the catalyst was reused for the third time. In addition, the photocatalytic mechanism was proposed, and the reactions followed the Langmuir–Hinshelwood model. The nano-PAA-NiO composite has an excellent effect for organic dye wastewater treatment and practical prospects in environmental protection.
Показать больше [+] Меньше [-]Effect of gibberellic acid on growth, biomass, and antioxidant defense system of wheat (Triticum aestivum L.) under cerium oxide nanoparticle stress Полный текст
2020
Iftikhar, Azka | Rizwan, Muhammad | Adrees, Muhammad | Ali, Shafaqat | ur Rehman, Muhammad Zia | Qayyum, Muhammad Farooq | Hussain, Afzal
Recently nanoparticles (NPs) are ubiquitous in the environment because they have unique characteristics which are the reason of their wide use in various fields. The release of NPs into various environmental compartments mainly ends up in the soil through water bodies which is a serious threat to living things especially plants. When present in soil, NPs may cause toxicity in plants which increase significance to minimize NPs stress in plants. Although gibberellic acid (GA) is one of the phytohormones that has the potential to alleviate abiotic/biotic stresses in crops plant, GA-mediated alleviation of cerium oxide (CeO₂) NPs in plants is still unknown, despite the large-scale application of CeO₂-NPs in various fields. The present study was performed to highlight the ability of foliar-applied GA in reducing CeO₂-NPs toxicity in wheat under soil exposure of CeO₂-NPs. We observed that CeO₂-NPs alone adversely affected the dry weights, chlorophyll contents, and nutrients and caused oxidative stress in plants, thereby reducing plant yield. GA coupled with CeO₂-NPs reversed the changes caused by CeO₂-NPs alone as indicated by the increase in plant growth, chlorophylls, nutrients, and yield. Furthermore, GA alleviated the oxidative stress in plants by enhancing antioxidant enzyme activities under CeO₂-NPs exposure than the NPs alone which further provided the evidence of reduction in oxidative damage in plants by GA. Overall, evaluating the potential of GA in reducing CeO₂-NPs toxicity in wheat could provide important information for improving food safety under CeO₂-NPs exposure.
Показать больше [+] Меньше [-]Alleviation of lead acetate-induced nephrotoxicity by Moringa oleifera extract in rats: highlighting the antioxidant, anti-inflammatory, and anti-apoptotic activities Полный текст
2020
Abdel-Daim, Mohamed M. | Alkahtani, Saad | Almeer, Rafa | Albasher, Gadah
Lead (Pb) is an environmental toxicant; its consumption can induce renal deficits. In this study, we explored the possible protective efficiency of Moringa oleifera extract (MOE) against lead acetate (PbAc)-mediated reprotoxicity. Four experimental groups of seven rats each were used: control, PbAc, MOE, and MOE+PbAc groups. All groups were given their respective treatment for 4 weeks. PbAc impaired the oxidative/antioxidative balance in the renal tissue, as shown by the decreased antioxidant proteins (glutathione, glutathione reductase, glutathione peroxidase, catalase, and superoxide dismutase) and increased oxidants (lipid peroxidation and nitric oxide). Additionally, PbAc enhanced the progression of kidney inflammation by increasing tumor necrosis factor-alpha, interleukin-1 beta, and nuclear factor kappa B associated with upregulation of inducible nitric oxide synthase. Moreover, a dysregulation in the apoptotic-regulating proteins (Bax, caspase-3, and Bcl2) were recorded upon PbAc exposure. Remarkably, MOE oral administration restored redox homeostasis, suppressed the inflammatory and apoptotic responses in the kidney tissue. Our findings point out that MOE could be used as an alternative remedy to overcome the adverse effects of Pb exposure, which may be due to its potent antioxidant, anti-inflammatory, and anti-apoptotic effects.
Показать больше [+] Меньше [-]An empirical study on energy utilization efficiency, economic development, and sustainable management Полный текст
2020
Pan, Xin-Xin | Chen, Mei-Lan | Ying, Li-Meng | Zhang, Fang-Fang
Based on the premise of sustainable development of the environment, how to achieve the balance of energy utilization, economic development, and sustainable management of the environment is becoming increasingly important in the process of stable economic development. This paper analyzes the concept of environmental Kuznets curve, taking 35 European countries as the research objects, first discusses the trend of energy utilization efficiency from 1990 to 2013, and then analyzes the relationship between energy efficiency and economic development. Empirical results show that labor has a significant negative impact on energy efficiency and the increase in labor input will reduce energy efficiency. If the added value of national manufacturing accounts for a higher percentage in GDP, it will have a negative impact on the effectiveness of energy utilization. In addition, when the national price level is high, price fluctuation will increase the price of energy utilization, or the cost of energy input in economic activities, which will further reduce the country’s energy efficiency performance. Lastly, the empirical study also found that energy efficiency and economic development showed a quadratic U-shaped relationship, indicating that the long-term energy efficiency of the country will first decline and then rise during economic activities.
Показать больше [+] Меньше [-]Geochemical features and potential environmental implications of heavy metals in mining-impacted sediments, south China Полный текст
2020
Yan, Bo | Xu, Da-Mao | Chen, Tao | Yan, ZiAng | Li, Lili
The present study was initiated to investigate the geochemical features and associated pollution risks of selected heavy metals in sediments near an active copper sulfide mines, south China. These results indicated that legacy contamination in sediments were mainly Cd (11.9 mg/kg), Cu (0.106%), Pb (0.189%), Zn (0.0958%), and As (0.158%). Furthermore, the geochemical variability of most elements, ranging from 5.66% for K₂O to 24.99% for Cd, was relatively lower. On the spatial scale, the variation patterns of multi-elements did not show a decreasing trend. The multivariate statistical analysis revealed that the significant enrichment of the studied elements was mostly related to the geochemical background and anthropogenic sources. Besides that, the stable climate might have positive influences on the leachability patterns of heavy metals in sediment profiles. According to the results of the potential ecological risk index (PERI), Cd, Cu, Pb, and As were identified as the riskiest elements due to their rather higher contribution ratios to pollution risk. In response to continuous exposure risks, the significant enrichment of these mining-derived elements should be preferentially concerned. Finally, some reasonable action is proposed for aquatic environment protection. Graphical abstract
Показать больше [+] Меньше [-]Phthalocyanine-sensitized evolution of hydrogen and degradation of organic pollutants using polyoxometalate photocatalysts Полный текст
2020
Wang, Ruixin | Liu, Yefeng | Zuo, Peng | Zhang, Zhendong | Lei, Nana | Liu, Yaqing
In this study, 2 (3), 9 (10), 16 (17), 23 (24)-tetrakis-(8-quinoline-oxy) phthalocyanine zinc(II) (ZnQPc) was prepared and then quaternized to obtain water soluble zinc phthalocyanine (ZnQPc⁴⁺). Then, ZnQPc⁴⁺ was used as a photosensitizer for a series of POM catalysts, including Dawson type K₆[α-P₂W₁₈O₆₂]·14H₂O (P₂W₁₈) and K₁₀[α-P₂W₁₇O₆₁]·20H₂O (P₂W₁₇) and Keggine type H₃PW₁₂O₄₀·xH₂O (PW₁₂). The Keggin type PW₁₂ showed higher efficiency with 18.2 μmol of H₂ evolution (turnover number (TON) = 14,550) for 6 h upon ZnQPc⁴⁺ sensitization in relation to two Dawson P₂W₁₇ and P₂W₁₈ in a visible light–driven water-soluble system with isopropanol and H₂PtCl₆·6H₂O. In addition, the complexes of ZnQPc⁴⁺ with a series of POM catalysts (P₂W₁₇, P₂W₁₈, and PW₁₂) were also used as photocatalysts for the degradation of methylene blue (MB) in water, and it was found that the complexes of ZnQPc⁴⁺ with P₂W₁₇ and PW₁₂ showed improved photocatalytic activity, and the degradation rates of MB reached 100% at a small dosage under natural pH and visible light. The high efficacy of POM catalysts for H₂ evolution and the degradation of MB were attributed to the sensitization of POMs by ZnQPc⁴⁺, which was enabled by the transfer of photogenerated electrons of ZnQPc⁴⁺ to the lowest unoccupied molecular orbital (LUMO) of POM.
Показать больше [+] Меньше [-]Bacterial-mediated synthesis of silver nanoparticles and their significant effect against pathogens Полный текст
2020
Saeed, Saira | Iqbal, Atia | Ashraf, Muhammad Aqeel
Silver nanoparticles are potent antimicrobials and could be used as a promising alternative of conventional antibiotics. The aim of this study was to isolate bacteria from soil that have ability to produce AgNPs by secondary metabolite activity and their elucidation against human pathogens. These strains Escherichia coli, Exiguobacterium aurantiacumm, and Brevundimonas diminuta with NCBI accession number MF754138, MF754139, and MF754140 respectively were grown for secondary metabolite production. The nanoparticles were confirmed and characterized by UV-Vis spectroscopy and transmission electron microscopy. The optimization study was also carried out to obtain the maximum production of silver nanoparticles. Three parameters, temperature, pH, and AgNO3 concentration, were used to optimize the production of silver nanoparticles. Antimicrobial potential of these nanoparticles was addressed on the Muller-Hinton Agar, and their zones of inhibitions were measured. TEM analysis revealed the size and shape of the silver nanoparticles. All types of AgNPs were spherical in shape; their size range is from 5 to 50 nm. The findings of optimization study showed the maximum production of silver nanoparticles at the pH 9, temperature 37 °C, and 1 mM AgNO3 concentration. All the strains exhibited the great potential as antimicrobial agents against MRSA and several other MDR bacteria with minimum 10 mm to maximum 28 mm zone of inhibition. It was concluded that the present study is an eco-friendly approach for the synthesis of AgNPs that will be beneficial to control the nosocomial infections triggered by MRSA and other human pathogens.
Показать больше [+] Меньше [-]Effects of extreme meteorological factors on daily mumps cases in Hefei, China, during 2011–2016 Полный текст
2020
Wu, Huabing | You, Enqing | Jiang, Chunxiao | Yang, Yuwei | Wang, Ling | Niu, Qingshan | Lu, Xuelei | Huang, Fen
Mumps remains one of the worldwide major health problems over the past decade. Seasonal variations of mumps indicate that meteorological factors play an important role in the development of mumps, but few studies have investigated the relationship between extreme meteorological factors and the incidence of mumps. Daily mumps cases and meteorological factors in Hefei, China, from 2011 to 2016 were obtained. A generalized additive model combined with the distributed lag nonlinear model (DLNM) was used to quantify the risk of extreme meteorological factors on mumps incidence. Nonlinear relationships were observed among all meteorological factors and mumps incidence. We found that extremely low and high temperatures increased the risk of mumps. The relative risks (RRs) of the cumulative effects along 30 lag days were 2.02 (95%CI: 1.14–3.56) and 2.42 (95%CI: 1.37–4.24), respectively. Both short and long sunshine duration had negative correlation on mumps, with cumulative RRs of 0.64 (95%CI: 0.46–0.92) and 0.57 (95%CI: 0.44–0.74), respectively. In the subgroup analysis, males were found to be more sensitive to extreme weather, especially extreme temperatures and sunshine duration. This study suggests that extreme meteorological factors, especially extreme temperatures and sunshine duration, exert a significant impact on the incidence of mumps. When formulating and implementing effective strategies to the prevention and control of mumps, authorities should take the effect caused by extreme meteorological factors into consideration and pay more attention to susceptible populations, such as male children and teenagers.
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