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A new perspective into the impact of renewable and nonrenewable energy consumption on environmental degradation in Argentina: a time–frequency analysis Texte intégral
2022
Adebayo, Tomiwa Sunday | Rjoub, Husam
In most nations across the world, the fundamental goal of economic policy is to achieve sustainable economic growth. Economic development, on the other hand, may have an influence on climate change and global warming, which are major worldwide concerns and problems. Thus, this research offers a new perceptive on the influence of renewable and nonrenewable energy consumption on CO₂ emissions in Argentina utilizing data from the period between 1965 and 2019. The current research applied the wavelet tools to assess these interconnections. The outcomes of these analyses reveal that the association between the series evolves over both frequency and time. The current analysis uncovers notable wavelet coherence and significant lead and lag connections in the frequency domain, while in the time domain, contradictory correlations are indicated among the variables of interest. From an economic perspective, the outcomes of the wavelet analysis affirm that in the medium and long term, renewable energy consumption contributes to environmental sustainability. Furthermore, in the medium term, trade openness mitigates CO₂, although in the long term, no significant connection was found. Moreover, both nonrenewable energy and economic growth contribute to environmental degradation in the short and long term. Finally, the frequency domain causality outcomes reveal that in the long term, economic growth, trade openness, and nonrenewable energy can predict CO₂ emissions. The present analysis offers an innovative insight into the interconnection and comovement between CO₂ and trade openness, renewable energy utilization, and GDP in the Argentinean economy. The findings from this research should be of interest to economists, researchers, and policymakers.
Afficher plus [+] Moins [-]Root anatomy, growth, and development of Typha domingensis Pers. (Typhaceae) and their relationship with cadmium absorption, accumulation, and tolerance Texte intégral
2022
de Oliveira, Jean Paulo Vitor | Pereira, Márcio Paulo | Duarte, Vinícius Politi | Corrêa, Felipe Fogaroli | de Castro, Evaristo Mauro | Pereira, Fabricio José
Typha domingensis Pers. is a plant that grows in marshy environments, where cadmium (Cd) accumulates. The root is the first organ that comes into contact with the metal. The aim of this study was to evaluate the effect of Cd on the roots of T. domingensis. The experiment was conducted in a greenhouse using different Cd concentrations: (1) 0 µM (control), (2) 10 µM, and (3) 50 µM, with 10 replicates for 90 days. The plants were placed in plastic containers containing 5 L of nutrient solution modified with the different Cd concentrations. At the end of the experiment, the roots were measured, sampled, fixed, and subjected to usual plant microtechniques. The slides were observed and photographed under light microscopy and analyzed in ImageJ software. To measure Cd absorption, atomic-absorption spectrometry was used. The data were subjected to analysis of variance and comparison of means by the Scott-Knott test at P < 0.05. When exposed to 50 µM of Cd, the roots accumulated 99.35% of the Cd. At this concentration, there was a reduction in the exodermis but there was an increase in the diameter of the cortical cells and in the proportion of aerenchyma in the cortex. There was an increase in the root cap, which guaranteed the protection of the primary meristems. Therefore, T. domingensis adjusts its root anatomy improving the Cd tolerance and shows potential for phytoremediation purposes.
Afficher plus [+] Moins [-]Chromatographic methods for the determination of a broad spectrum of UV filters in swimming pool water Texte intégral
2022
Mokh, Samia | Nassar, Rania | Berry, Atika | Khatib, Mohammad El | Doumiati, Samah | Taha, Mariam | Ezzeddine, Raed | Al Iskandarani, Mohamad
This paper describes an analytical approach based on solid-phase extraction (SPE) followed by analysis using liquid and gas chromatography coupled to mass spectrometry detectors for a determination of 18 organic UV filters from water samples. Extraction method parameters were optimized: 250 ml of water sample loaded on Chromabond C18 cartridges after adjustment to pH 4 and then eluted with acetonitrile. The mobile phase and the parameters of the mass spectrometer, as well as those of the ionization source, were tested to enhance detection sensitivity. During method validation, the extracted target compounds showed good recoveries (> 68%) with acceptable values in terms of repeatability (RSDᵣ) and reproducibility (RSDR), where relative standard deviations values were lower than 20%. The validated method was applied to 10 water samples collected from different swimming pools located in Lebanon from which eight UV filters among the eighteen targets compounds were detected at concentrations ranged between 1 and 2526 µg L⁻¹. The most detected compounds were padimate-O (OD-PABA) and octocrylene (OCR). This study represents the first available data on the occurrence of UV filter residues in Lebanese swimming pool opening hence future perspectives and insights to evaluate their degradation by-products and their toxicity on human health and marine ecosystem.
Afficher plus [+] Moins [-]Measuring economic, social and environmental wellbeing of Asian economies Texte intégral
2022
Sharmin, Mowshumi | Dey, Sima Rani | Islam, Md Tariqul
This study aims to address the economic, social, and environmental wellbeing issues simultaneously by measuring the carbon intensity of wellbeing (CIWB) of Asian economies employing Prais-Winsten and pooled OLS estimator. The measure of CIWB is made taking into account a ratio of the two indicators—CO₂ emissions per capita and life expectancy at birth. There is a paucity of studies that concentrate on human and social wellbeing indicators (i.e., water, sanitation, life expectancy) together applying the Environmental Kuznets Curve (EKC) hypothesis. Therefore, we have also investigated the EKC hypothesis as this theory hypothesizes the link involving human and environmental wellbeing and development. The findings utilizing the two econometric techniques indicate that in both the estimation models urban population access to an improved water source and total population access to improved water source has consistently negative and significant effects on CIWB. The fertility rate and prevalence of HIV pose no threat to CIWB. These findings demonstrate that social and human wellbeing indicators of the Asian economies are sustainable to this moment as they are lowering CIWB which is desirable. Contrary, GDP per capita, exports as a percent of GDP, and urban population have a significant and positive impact on CIWB which poses a challenge for the sustainability issue. We also have found the existence of the EKC hypothesis indicating environmental quality will increase past a turning point. The findings of the paper are well matched with the view of the “Economic and ecological modernization” theory and “human ecology” theory.
Afficher plus [+] Moins [-]Polybrominated diphenyl ethers BDE-47 and BDE-99 modulate murine melanoma cell phenotype in vitro Texte intégral
2022
Steil, Gisleine Jarenko | Buzzo, João Luiz Aldinucci | de Oliveira Ribeiro, Ciro Alberto | Filipak Neto, Francisco
Cancer is one of the leading causes of mortality worldwide. Even with the advances of pharmaceutical industry and treatments, the mortality rate for various types of cancer remains high. In particular, phenotypic alterations of tumor cells concerning drug efflux, migratory and invasive capabilities may represent a hurdle for cancer treatment and contribute to poor prognosis. In the present study, we investigated the effects of polybrominated diphenyl ethers (PBDEs) used as flame retardants on phenotypic features of melanoma cells that are important for cancer. Murine melanoma B16-F1 (less metastatic) and B16-F10 (more metastatic) cells were exposed to 0.01–1.0 nM of BDE-47 (2,2′,4,4′-tetrabromodiphenyl ether), BDE-99 (2,2′,4,4′,5-pentabromodiphenyl ether), and the mixture of both (at 0.01 nM) for 24 h (acute exposure) and 15 days (chronic exposure). The polybrominated diphenyl ethers (PBDEs) did not affect cell viability but led to increased drug efflux transporter activity, cell migration, and colony formation, as well as overexpression of Abcc2 (ATP-binding cassette subfamily C member 2), Mmp-2 (matrix metalloproteinase-2), Mmp-9 (matrix metalloproteinase-9), and Tp53 (tumor protein p53) genes and downregulation of Timp-3 (tissue inhibitor of metalloproteinase 3) gene in B16-F10 cells. These effects are consistent with increased aggressiveness and malignancy of tumors due to exposure to the flame retardants and raise some concerns on the effects such chemicals may have on melanoma treatment and cancer prognosis.
Afficher plus [+] Moins [-]The effect of salinity on the interaction between microplastic polyethylene terephthalate (PET) and microalgae Spirulina sp Texte intégral
2022
Hadiyanto, Hadiyanto | Muslihuddin, Muslihuddin | Khoironi, Adian | Pratiwi, Wahyu Zuli | Fadlilah, Muthia’ah Nur | Fuad, Muhammad | Afiati, Norma | Dianratri, Inggar
The increasing use of plastic over the last few decades has had an impact of plastic pollution in aquatic ecosystems. Plastic pollutions may be in the form of microplastics either from primary or secondary sources. These microplastics will indirectly affect human health through the food chain. This research was aimed at evaluating the interaction between microplastic and microalgae that are a source of food supplements. The experiment was conducted by investigating the impact of microplastic polyethylene terephthalate (PET) on microalga Spirulina sp. cultivated in fresh water and saline water (7 ppt salinity) for 14 days. The growth rate and morphology of Spirulina sp. and PET were evaluated. The result showed that the presence of PET and salinity decreased Spirulina sp. growth rate in cultivation by 0.174 day⁻¹ and reduced nutrient removal rates. However, the salinity system on medium-added PET was indicated that there are influences of Spirulina sp. against PET, where PET can be degraded by Spirulina sp. in the state of water with a salinity 7 ppt. FTIR graphic seems if there is any peak declination within PET augmentation in media with 0 ppt salinization. Nonetheless, the peak augmentation happened within PET augmentation in media with 7 ppt salinity. This signifies if there is an augmentation of PET salinization can be degraded by Spirulina sp. as the polysaccharide sources. PET is resistant to degradation due to its aromatic group. Based on the results scanning electron microscope (SEM), Spirulina sp. which growth with PET had a more uneven shape compared with a control variable.
Afficher plus [+] Moins [-]A perspective review on medicinal plant resources for their antimutagenic potentials Texte intégral
2022
Malik, Sumira | Kaur, Kawaljeet | Prasad, Shilpa | Jha, Niraj Kumar | Kumar, Vinay
Mutagens present in the environment manifest toxic effects and are considered as serious threat for human health and healthcare. Recent reports reveal that medicinal plant resources are being explored for identifying potent antimutagenic as well as cancer preventing agents. There is mounting evidence that cancer and other mutation-related diseases can be prevented with the use of medicinal pant resources including crude extracts, active fractions, phytochemicals, and pure phytomolecules. These medicinal plant resources possessing antimutagenic potentials have been shown to target molecular mechanisms underlying the mutagenic impacts. Technological advents and high-throughput screening/activity methods have revolutionized this field, though several potent plants and their active principles have been reported as effective antimutagens. The translational success rate needs to be improved, but the trends are encouraging. In this review, we present the current understandings and updates on various mutagens in the environment, toxicities related/attributed to them, the resultant mutations (and cancer), and how medicinal plants come to the rescue. A perspective review has been presented on whether and how medicinal plant resources can be an effective approach for addressing mutagens in the environment. An account of medicinal plant resources used as antimutagenic agents has been given along with the underlying mechanism of action and their therapeutic potential in various models of cancer. Recent success stories, current challenges, and future prospects are discussed.
Afficher plus [+] Moins [-]The effects of anaerobic reactor post-treatments by rapid filtration systems and conventional techniques Texte intégral
2022
da Silva, Cleber Pinto | de Campos, Sandro Xavier
Although anaerobic reactors are an excellent alternative in the treatment of domestic effluents, they have the disadvantage of requiring post-treatment. Many technologies have been studied and, recently, rapid filtration systems have been presented as a viable alternative for post-treatment. This work compared post-treatment techniques for anaerobic upflow sludge blanket (UASB) reactors by rapid filtration systems (double filtration (DF); triple filtration with clinoptilolite (TFc); and triple filtration with activated carbon (TFac)) to conventional systems (facultative pond (FP); biological filter (BF); biological filter with recirculation and decantation (BFD)), verifying their potential for improvement of the final effluent quality. The UASB effluent post-treatments by FP, BF, BFD, DF, TFc, and TFac were evaluated. The removal of turbidity in both BFD and FP post-treatments was below 75%. The DF, TFc, and TFac treatments showed over 99% removal of the same parameters. COD removal in the FP, BF, and BFD post-treatments was over 10%, while in the DF, TFc, and TFac treatments, it was over 80%. The greatest total phosphorus removal was observed in TFc and TFac, whose values were over 99%. The best removal of ammoniacal nitrogen, 99% was observed in the TFc treatment. Regarding Al, Cd, Cr, Cu, Mn, Ni, Pb, and Zn removal, all rapid filtration systems showed better performance when compared to conventional systems. The DF, TFc, and TFac systems showed over 90% removal of most metals evaluated, while the FP and BF treatments presented values below 50% for most metals, and in the BFD system, the removal values were below 80% for most metals. The results indicate that rapid filtration systems were better at removing all evaluated parameters when compared to conventional systems.
Afficher plus [+] Moins [-]Modified fractional-order model for biomass degradation in an up-flow anaerobic sludge blanket reactor at Zenein Wastewater Treatment Plant [Erratum: April 2022, v.29(17); p.25987] Texte intégral
2022
El-Seddik, Mostafa M. | Galal, Mona M. | Rozaik, Ehab H. | Radwan, Ahmed G.
This paper presents a modified fractional-order model (FOM) for microorganism stimulation in an up-flow anaerobic sludge blanket (UASB) reactor treating low-strength wastewater. This study aimed to examine the famine period of methanogens due to biomass accumulation in the UASB reactor over long time periods at a constant organic loading rate (OLR). This modified model can investigate the substrate biodegradation in a UASB reactor while considering substrate diffusion into biological granules during the feast and famine periods of methanogens. The Grünwald-Letnikov numerical technique was used to indicate the effect of biomass degradation on the biogas production rate and substrate biodegradation in a UASB reactor installed at Zenein Wastewater Treatment Plant (WWTP) in Giza, Egypt. Several fractional orders were applied in the dynamic model at biomass concentrations of [Formula: see text] and [Formula: see text] in the reactor bed and blanket zones, respectively. An OLR of [Formula: see text] using the calibrated kinetic parameters at [Formula: see text] was applied to comply with the experimental outcomes. The simulation results indicate that the removal efficiency of chemical oxygen demand (COD) was maintained at approximately [Formula: see text], whereas the biogas production rate declined from [Formula: see text] in the reactor bed zone due to a decline in food to microorganism (F/M) ratio from [Formula: see text] during the sludge retention time (SRT) in the UASB reactor.
Afficher plus [+] Moins [-]Potential ability of tobacco (Nicotiana tabacum L.) to phytomanage an urban brownfield soil Texte intégral
2022
Di Lodovico, Eliana | Marchand, Lilian | Oustrière, Nadège | Burges, Aritz | Capdeville, Gaelle | Burlett, Régis | Delzon, Sylvain | Isaure, Marie-Pierre | Marmiroli, Marta | Mench, Michel J.
The ability of tobacco (Nicotiana tabacum L. cv. Badischer Geudertheimer) for phytomanaging and remediating soil ecological functions at a contaminated site was assessed with a potted soil series made by fading an uncontaminated sandy soil with a contaminated sandy soil from the Borifer brownfield site, Bordeaux, SW France, at the 0%, 25%, 50%, 75%, and 100% addition rates. Activities of sandblasting and painting with metal-based paints occurred for decades at this urban brownfield, polluting the soil with metal(loid)s and organic contaminants, e.g., polycyclic aromatic hydrocarbons, in addition to past backfilling. Total topsoil metal(loid)s (e.g., 54,700 mg Zn and 5060 mg Cu kg⁻¹) exceeded by seven- to tenfold the background values for French sandy soils, but the soil pH was 7.9, and overall, the 1M NH₄NO₃ extractable soil fractions of metals were relatively low. Leaf area, water content of shoots, and total chlorophyll (Chl) progressively decreased with the soil contamination, but the Chl fluorescence remained constant near its optimum value. Foliar Cu and Zn concentrations varied from 17.8 ± 4.2 (0%) to 27 ± 5 mg Cu kg⁻¹ (100%) and from 60 ± 15 (0%) to 454 ± 53 mg Zn kg⁻¹ (100%), respectively. Foliar Cd concentration peaked up to 1.74 ± 0.09 mg Cd kg⁻¹, and its bioconcentration factor had the highest value (0.2) among those of the metal(loid)s. Few nutrient concentrations in the aboveground plant parts decreased with the soil contamination, e.g., foliar P concentration from 5972 ± 1026 (0%) to 2861 ± 334 mg kg⁻¹ (100%). Vulnerability to drought-induced embolism (P50) did not differ for the tobacco stems across the soil series, whereas their hydraulic efficiency (Ks) declined significantly with increasing soil contamination. Overall, this tobacco cultivar grew relatively well even in the Borifer soil (100%), keeping its photosynthetic system healthy under stress, and contaminant exposure did not increase the vulnerability of the vascular system to drought. This tobacco had a relevant potential to annually phytoextract a part of the bioavailable soil Zn and Cd, i.e., shoot removals representing here 8.8% for Zn and 43.3% for Cd of their 1M NH₄NO₃ extractable amount in the potted Borifer soil.
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