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Influence of eco-friendly phytotoxic metabolites from Lasiodiplodia pseudotheobromae C1136 on physiological, biochemical, and ultrastructural changes on tested weeds Full text
2020
Adetunji, Charles Oluwaseun | Oloke, Julius Kola | Phazang, Paomipem | Sarin, Neera Bhalla
In this study, the active metabolites from both the wild strain of Lasiodiplodia pseudotheobromae C1136 and three genetically enhanced strains of C1136 were obtained through random mutagenesis. The effect of the active metabolites from these strains was evaluated in relation to physiological, biochemical, and ultrastructural changes on the leaves of two weeds (Amaranthus hybridus and Echinochloa crus-galli). The phytotoxic metabolites secreted by the genetically enhanced strains showed a decrease in the pigments (chl a, chl b, and carotenoids), carbohydrate content, and the amino acid profile. On the other hand, an increase in total phenols of the tested leaves was observed when compared with the untreated leaves. The scanning electron microscopy showed the presence of damages, necrosis, degradation, and ultrastructural changes on the tested leaf tissues of the weeds. Also, increased lipid peroxidation and electrolyte leakage were also observed on the tested weeds treated with phytotoxic metabolites secreted by the genetically enhanced strains. We also showed that the phytotoxins from the strains of C1136 are biocompatible and that it improved soil CO₂ evolution, organic carbon content, and enzymatic activity (acidic and alkaline phosphatase, dehydrogenases, cellulase, catalase). The study validates the severe pathological effects of phytotoxic metabolites from the strains of C1136 on the leaves of the weeds presented in this study. The mode of action of the phytotoxic metabolites produced from this bioherbicidal isolates will go a long way in preventing environmental hazards.
Show more [+] Less [-]Ameliorative effect of boric acid against formaldehyde-induced oxidative stress in A549 cell lines Full text
2020
Arslan-Acaroz, Damla | Bayşu-Sozbilir, Nalan
Formaldehyde (HCHO) is a reactive agent and the most essential common carcinogenic environmental pollutant. The present study investigated the protective and ameliorative effects of boric acid (BA) against formaldehyde-induced oxidative stress in A549 cell lines. The first group served as a control, the second group was treated with only 100 μM formaldehyde, and the third, fourth, and fifth groups were treated with 2.5, 5, and 10 mM BA, respectively. The sixth, seventh, and eighth groups were treated with 2.5, 5, and 10 mM BA plus 100 μM formaldehyde, respectively. In A549 cell lines, formaldehyde treatment significantly decreased cell viability, glutathione level, and enzyme activities of superoxide dismutase and catalase; however, malondialdehyde levels of the cell lysate were found to increase compared with the control group. In addition, formaldehyde treatment did not significantly alter nitric oxide levels. Meanwhile, mRNA expression levels of Tnf-α, NFĸB, and caspase-3 significantly increased but the Bcl-XL level did not show significant alteration by formaldehyde treatment. In contrast, the BA treatment reversed the formaldehyde-induced alteration in A549 cell lines. Consequently, BA exhibited a protective effect in A549 cell line against formaldehyde-induced lipid peroxidation. Furthermore, it ameliorated the antioxidant status and mRNA expression levels of proinflammatory cytokines.
Show more [+] Less [-]Adverse effects of fly ashes used as immobilizing agents for highly metal-contaminated soils on Xenopus laevis oocytes survival and maturation—a study performed in the north of France with field soil extracts Full text
2020
Marchand, Guillaume | Demuynck, Sylvain | Slaby, Sylvain | Lescuyer, Arlette | Lemière, Sébastien | Marin, Matthieu
Amphibians are now recognized as the most endangered group. One of this decline causes is the degradation of their habitat through direct contamination of water, soil leaching, or runoff from surrounding contaminated soils and environments. In the North of France, the extensive industrial activities resulted in massive soil contamination by metal compounds. Mineral amendments were added to soils to decrease trace metal mobility. Because of the large areas to be treated, the use of inexpensive industrial by-products was favored. Two types of fly ashes were both tested in an experimental site with the plantation of trees in 2000. Aim of the present work was to investigate the effects of extracts from metal-contaminated soils treated or not for 10 years with fly ashes on Xenopus laevis oocyte using cell biology approaches. Indeed, our previous studies have shown that the Xenopus oocyte is a relevant model to study the metal ion toxicity. Survival and maturation of oocyte exposed to the soil extracts were evaluated by phenotypic approaches and electrophysiological recordings. An extract derived from a metal-contaminated soil treated for 10 years with sulfo-calcic ashes induced the largest effects. Membrane integrity appeared affected and ion fluxes in exposed oocytes were changed. Thus, it appeared that extracted elements from certain mineral amendments used to prevent the mobility of metals in the case of highly metal-contaminated soils could have a negative impact on X. laevis oocytes.
Show more [+] Less [-]Application of ANN and RSM on fluoride removal using chemically activated D. sissoo sawdust Full text
2020
Joshi, Saurabh | Bajpai, Shailendra | Jana, Somen
Response surface methodology (RSM) and artificial neural network (ANN) were used to generate a model for the optimization of fluoride removal using chemically activated Dalbergia sissoo sawdust (CADS). The single and collective effects of process parameters, i.e., solution pH, CADS dose, initial fluoride concentration, and contact time, were studied. The point of zero charge was found to be 4.2 with zeta potential analysis. In the first phase, a single-parameter study was performed to reveal dependency of fluoride removal on a particular process parameter. Positive effects of increment in CADS dose and contact time and negative effects of solution pH and initial fluoride concentration were observed. The second phase included RSM in which analysis of variance (ANOVA) was applied to test the feasibility of the mathematical model. The F value 1.91, R² value 0.87, and P value 0.11 show significance of the proposed model. Results obtained from the experiment set for central composite design (CCD) were used to predict the ANN response. Reasonable acceptable values of regression for training, test, and validation (0.76, 0.93, and 0.37) represent the suitability of the model. The ANN predicted 22.1% fluoride removal, which was close to the actual value (20.1%) and was comparable with CCD prediction (25.0%). BET surface area of CADS was found to be 76.33 m²/g. FTIR was performed to recognize the functional groups available for fluoride binding while SEM and EDX were conducted to ensure the changes in adsorbent surface morphology. Regeneration of CADS was feasible using an alkali medium. This study shows that CADS can be used for fluoride removal from aqueous stream in an efficient way.
Show more [+] Less [-]Characterization of anthropogenic materials on yellow-legged gull (Larus michahellis) nests breeding in natural and urban sites along the coast of Portugal Full text
2020
Lopes, Catarina S. | de Faria, Joana Pais | Paiva, Vitor H. | Ramos, Jaime A.
Anthropogenic materials are a persistent pressure on ecosystems, affecting many species. Seabirds can collect these materials to construct their nests, which may modify nest characteristics and cause entanglement of chicks and adults, with possible consequences on breeding success. The incorporation of anthropogenic materials in nests of seabird species that breed in both natural and urban environments, such as gulls, is poorly known. Here, we characterize and compare anthropogenic materials incorporated in yellow-legged gull (Larus michahellis) nests from two natural and two urban breeding sites across their Portuguese breeding range and during 2 consecutive years. Anthropogenic materials were found in 2.6% and 15.4% of gull nests from natural locations and in 47.6% and 95.7% of nests from urban breeding sites. No differences were found on hatching success between urban and natural breeding colonies. A significantly higher number of anthropogenic materials were found in the largest and more populated urban breeding colony, which on average included items of a greater mass but smaller size than items from the other three colonies. The higher incorporation of anthropogenic materials in urban locations could be a consequence of a lower access to natural nest construction materials and higher availability of anthropogenic debris. The quantity and diversity of anthropogenic materials incorporated in gull nests from urban locations indicate a need for improved debris management in urban settlements.
Show more [+] Less [-]Short-term effects of meteorological factors, air pollution, and sunspot on childhood hand, foot, and mouth disease in Tianjin, China: a new time series regression, 2014–2018 Full text
2020
Ji, Xue-Yue | Huang, Li-Yuan | Song, Jia | Fei, Chun-Nan | Liu, Jun | Liu, He
This study is aimed at defining the relationship between a set of environmental factors and childhood HFMD and then at estimating the related effect. The 16 environmental factors included meteorological, air pollution, and sunspot. A traditional TSR modified by using susceptible-infectious-recovery models and distribution lag nonlinear model was applied to estimate the short-term effects of daily environmental factors on children HFMD occurrence in 2014–2018 with adjustment of potential confounding factors. A total of 70,027 children aged 0–15 years with HFMD were enrolled. No significant effect was observed for daily sunspot numbers and average visibility. We found positive effects of the ambient average temperature, with an approximately m-shaped curve of the overall cumulative relationship, peaking at 25.6 °C with a relative risk (RR) of 1.45 (95% confidence intervals 1.21–1.73). The largest RR value of hot effect was achieved on the current day and then decreased by 2 days (total group, male group, and scatter group) or 1 day (female group and nursery group), and the effect lasted about 6 to 8 days from the lag 4 or lag 6 day. A greater association of temperature with HFMD for the female group and the scattered group was observed. This study suggests that ambient average temperature might be a risk factor for children HFMD in Tianjin. Further studies are warranted to confirm these findings.
Show more [+] Less [-]Chronic sublethal effects of ZnO nanoparticles on Tigriopus fulvus (Copepoda, Harpacticoida) Full text
2020
Prato, Ermelinda | Parlapiano, Isabella | Biandolino, Francesca | Rotini, Alice | Manfra, Loredana | Berducci, Maria Teresa | Maggi, Chiara | Libralato, Giovanni | Paduano, Luigi | Carraturo, Federica | Trifuoggi, Marco | Carotenuto, Maurizio | Migliore, Luciana
This study investigated for the first time the effects of ZnO nanoparticle (NP) chronic exposure (28 days) on Tigriopus fulvus. Acute toxicity (48 h) of three Zn chemical forms was assessed as well including the following: (a) ZnO nanoparticles (NPs), (b) Zn²⁺ from ZnO NP suspension after centrifugation (supernatant) and (c) ZnSO₄ H₂O. Physical-chemical and electronic microscopies were used to characterize spiked exposure media. Results showed that the dissolution of ZnO NPs was significant, with a complete dissolution at lowest test concentrations, but nano- and micro-aggregates were always present. Acute test evidenced a significant higher toxicity of Zn²⁺ and ZnSO₄ compared to ZnO NPs. The chronic exposure to ZnO NPs caused negative effects on the reproductive traits, i.e. brood duration, brood size and brood number at much lower concentrations (≥ 100 μg/L). The appearance of ovigerous females was delayed at higher concentrations of ZnO NPs, while the time required for offspring release and the percentage of non-viable eggs per female were significantly increased. ZnO NP subchronic exposure evidenced its ability to reduce T. fulvus individual reproductive fitness, suggesting that ZnO NPs use and release must be carefully monitored. Graphical abstract Graphical Abstract.
Show more [+] Less [-]Assessing the integration of solar power projects: SWOT-based AHP–F-TOPSIS case study of Turkey Full text
2020
Anser, Muhammad Khalid | Mohsin, Muhammad | Abbas, Qaiser | Chaudhry, Imran Sharif
Solar energy systems are a cheaper and easy solution to cope with severe energy crisis especially in emerging economies including Turkey which exerted huge efforts to enhance the existing solar power projects. However, the selection of the optimal site for the installation of solar projects needs vigorous investigation through various factors. Adequate quantitative scientific research is required for the process of site selection in Turkey. This paper categorizes various sites in Turkey through various factors such as economic, environmental, and social factors. Various major criteria have been combined through mathematical development to install the solar power project in remote areas of Turkey. The scientific evaluation of remote and rural solar projects in Turkey has been taken as a case study in the current paper. Additionally, the analytical hierarchy process (AHP) and F-VIKOR methods were used to aggregate the criteria. The results show that economic and social ratio is significant, whereas the transmission matrix, land cost, and the sun irradiance got a major score in order to generate electricity. The study results show that total sunshine time per year determined is 2741 h (a total of 7.5 h per day) and the total solar energy obtained each year is 1527 kWh per square meter per year (a total of 4.18 kWh per square meter per day).
Show more [+] Less [-]Miswak (Salvadora persica) modulated the growth performance, antioxidative response, and histopathological damage induced by zinc toxicity in Nile tilapia (Oreochromis niloticus) Full text
2020
Abd El-Naby, Asmaa S. | El Asely, Amel M. | Amin, Aziza A. | Samir, Fatma | El-Ashram, Ahmed | Dawood, Mahmoud A. O.
In this study, Nile tilapia fingerlings with average body weight (8.6 ± 0.06 g) were exposed to zinc (Zn) toxicity and tested its amelioration with miswak (Salvadora persica L.) (SP) supplemented diet. Five fish groups were fed on diets with SP at 0, 0.25, 0.5, 1.0, and 2.0% (T1, T2, T3, T4, and T5, respectively) diet without Zn exposure, while another five groups were exposed to Zn at 7 mg/L and co-supplemented with SP at 0, 0.25, 0.5, 1.0, and 2.0 % (T6, T7, T8, T9, and T10, respectively). After 12 weeks, fish-fed 1.0% SP diet (T4) achieved the highest growth and feed performances, while the lowest one was in Zn-exposed fish (T6) (P < 0.05). T6 and T7 groups showed the most inferior carcass protein and ash contents, while T4 and T5 showed the highest lipid content (P < 0.05). The level of Zn residue increased in fish exposed to Zn (P < 0.05). Fish exposed to Zn and fed SP showed high blood urea, catalase, ALT, AST, and total superoxide dismutase (T-SOD), while the malondialdehyde (MDA) was decreased (P < 0.05). Interestingly, miswak resulted in elevated catalase and T-SOD and reduced MDA in fish without Zn exposure (P < 0.05). Zn exposure causes abnormal histopathological characteristics in gills, hepatopancreas, posterior kidney, and musculature tissues of tilapia, while fish-fed SP showed regular, healthy, and protected histopathological characters. The results suggested that SP can induce the antioxidant responses that prepare Nile tilapia for a further suppressive oxidative condition (i.e., Zn exposure).
Show more [+] Less [-]Fiscal decentralization, environmental regulation, and pollution: a spatial investigation Full text
2020
Chen, Xia | Chang, Chun-Ping
To investigate the effects of regulation on environmental pollution under Chinese-style fiscal decentralization, this research analyzes annual data over the period 2003 to 2017 covering 30 provinces in China with the spatial economic model. The empirical results show significant spatial agglomeration effects on the emissions of wastewater, sulfur dioxide, and solid waste. Environmental regulation helps reduce discharge of wastewater and solid waste, but does not help reduce the emission of sulfur dioxide; because there is significantly positive externality in treating pollutants with high fluidity, cost is larger than revenue for local governments. The relationship between fiscal decentralization and pollutants shapes an inverted U-shaped curve. We finally offer some implications in accordance with our empirical finding, such as the intensity of environmental regulation should be suitable for economic development, different measures should be taken based on the fluidity of pollutants, and a new evaluation system should be established.
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