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What is the possible therapeutic effect of Ginkgo biloba on gastric ulcer induced by ammonia in albino rats? Полный текст
2020
El-Medany, Azza | Guemei, Aida Ahmed Said | Abdel Twab, Raeesa | Al-Matrafi, Tahani | El-Medany, Jamila
Gastric ulcer is a worldwide disease. Helicobacter pylori is one of the most common chronic bacterial infections that induce chronic inflammation in the gastric mucosa, mediated by an array of pro-and inflammatory cytokines. The aim of this study was to investigate the possible therapeutic effects of Ginkgo biloba extract on gastric ulcer induced by ammonium hydroxide in rats and the potential underlying mechanisms. The study was done on 32 adult male Wistar albino rats, divided equally into 4 groups: normal control, gastric ulcer–induced group using 1 ml of 1% NH₄OH orally, ulcer control group; rats received 1% carboxymethyl cellulose daily for 14 days after induction of ulcer and treated rats received orally 200 mg/kg Ginkgo biloba once daily for 14 days after induction of ulcer. The study revealed administration of ammonia showed multiple gastric lesions; edema, hyperemia, hemorrhage, and ulcers with a significant increase in ulcer score, myeloperoxidase (MPO), and interleukin-1β (IL-1β) and a significant decrease in reduced glutathione (GSH), mucus amount, and gastric pH. After the administration of Ginkgo biloba, there was an improvement in gastric lesions, with a significant reduction of ulcer score, MPO, and IL-1β and a significant increase in GSH, mucus content, and gastric pH. Moreover, collagen types I and IV were gradually increased in the treated group.
Показать больше [+] Меньше [-]Biochars derived from crop straws increased the availability of applied phosphorus fertilizer for maize in Ultisol and Oxisol Полный текст
2020
Baquy, M Abdulaha-Al | Jiang, Jun | Xu, Renkou
The extensive use of phosphorus (P) fertilizer is a common practice due to the suboptimal P in variable charge soils for better crop growth. The aim of this study was to increase our understandings and disclose the mechanisms for increase in P availability in Ultisol and Oxisol by biochars derived from crop straws. Incubation and greenhouse pot experiments were conducted to attain the objective. Results from incubation study indicated that biochars derived from different crop straws increased P recovery in both Ultisol and Oxisol. Biochars increased the repulsion of soil surface to phosphate (PO₄³⁻) anions due to increased soil CEC, and thus increased P recovery; acidic functional groups on biochars competed for soil sorption sites with PO₄³⁻, and thus increased P recovery. While the formation of insoluble PO₄³⁻ with divalent cations of calcium (Ca) and magnesium (Mg) from the biochars reduced P recovery. P recovery was increased with increasing soil pH and biochar application rate for each biochar type. The lower content of Ca²⁺ and Mg²⁺ in rice straw biochar led to greater increase in P recovery than canola and peanut straw biochars. When two soils were compared with each other, P recovery was higher in Ultisol than Oxisol due to the presence of large amount of Fe and Al oxides in Oxisol. Results from pot experiment showed that plant dry matter yield and P recovery by maize were increased with increasing rate of rice straw biochar applied over control. Therefore, application of P fertilizer in rice straw biochar–amended soils will increase P availability to crops and thus crop yields in variable charge soils.
Показать больше [+] Меньше [-]Leaf defense capacity of Japanese elm (Ulmus davidiana var. japonica) seedlings subjected to a nitrogen loading and insect herbivore dynamics in a free air ozone-enriched environment Полный текст
2020
Sugai, Tetsuto | Okamoto, Shota | Agathokleous, Evgenios | Masui, Noboru | Satoh, Fuyuki | Koike, Takayoshi
Japanese elm (Ulmus davidiana var. japonica) is a native species in cool-temperate forests in Japan. We investigated growth, physiological reactions, and leaf defense capacity of Japanese elm seedlings under nitrogen (N) loading (45.3 kg N ha⁻¹ year⁻¹) and seasonal insect dynamics in a free-air ozone (O₃)-enriched environment (about 54.5 nmol O₃ mol⁻¹) over a growing season. Higher leaf N content and lower condensed tannin content in the presence of N loading and lower condensed tannin content in elevated O₃ were observed, suggesting that both N loading and elevated O₃ decreased the leaf defense capacity and that N loading further enhanced the leaf quality as food resource of insect herbivores. Two major herbivores were observed on the plants, elm leaf beetle (Pyrrhalta maculicollis) and elm sawfly (Arge captiva). The peak number of observed insects was decreased by N loading. Visible foliar injury caused by N loading might directly induce the reduction of number of the observed elm sawfly individuals. While elevated O₃ slightly suppressed the chemical defense capacity, significantly lower number of elm leaf beetle was observed in elevated O₃. We conclude that N loading and elevated O₃ can alter not only the leaf defense capacity of Japanese elm seedlings but also the dynamics of elm leaf beetle and sawfly herbivores.
Показать больше [+] Меньше [-]Pathways regulating nitrogen removal in constructed ditch wetlands: effects of different inflow ratios and artificial aeration Полный текст
2020
Constructed ditch wetland (CDW) is a combination of idle ditch and constructed wetland, which is typically used in rural areas to remove pollutants from domestic wastewater. However, its low total nitrogen (TN) removal remains a pressing issue. To enhance total nitrogen removal, an approach of supplying water at two locations in the CDW at different influent flow ratios, combined with artificial aeration, was proposed to adjust carbon and oxygen distribution in the system. The highest average TN removal was achieved at low influent concentration (CDW4; influent flow ratio 1:2). The removal of TN in winter and spring were 58.93 and 83.26%, respectively. The distribution of carbon sources in the back zone enhanced denitrification. Of the high influent concentration treatments, CDW2 (2:1) achieved 16.97% more TN removal on average compared with CDW1 (3:0), after extra artificial aeration was applied in the front zone. However, nitrification was a limiting step in the system, which became the primary problem preventing pollutant purification. Moreover, nitrifying bacteria abundance was negatively correlated to the influent flow ratio and autotrophic denitrifying bacterial abundance was positively correlated to the influent flow ratios. Graphical abstract
Показать больше [+] Меньше [-]Multi-route human health risk assessment from trihalomethanes in drinking and non-drinking water in Abadan, Iran Полный текст
2020
Natural organic matter reacted with chlorine used for disinfection, and finally, trihalomethanes (THMs) are formatted. The main purpose of this study was to determine four THM concentrations and human health cancer risk and non-cancer risk assessment from exposure through oral ingestion, dermal contact, and inhalation for males and females in Abadan. Two sampling sites were selected, and five samples before and after treatment by two different water treatment systems (RO and ion exchange) were collected every week. Results showed that total THM concentrations before and after treatment by RO were 98.1 and 8.88 μg/L, and ion exchange ranged between 101.9 and 14.96 μg/L, respectively, that before treatment was upper than the maximum of 80 mg/L recommended by USEPA. Inhalation was the primary route of exposure by around 80–90% of cancer risk. Total cancer risk was higher than the USEPA acceptable limit of 10⁻⁶ via three exposure routes. Oral route has the higher hazard index values than dermal ways.
Показать больше [+] Меньше [-]Bulk and water-extractable organic matter from compost: evaluation of the selective dissolution in water using infrared absorbance ratios Полный текст
2020
Land application of composts affects concentration and composition of dissolved organic matter (OM) which plays important roles in soil functioning and may have effects on spreading of environmental pollution. Linking between the composition of bulk compost OM and its water-soluble fraction may, therefore, allow better understanding and prediction of the environmental impact of compost added to soil. The objectives of this study were to (i) examine composition-based links between bulk compost OM and water-extractable OM (WEOM), and (ii) evaluate and quantify selectivity of bulk compost OM dissolution, based on infrared (IR) absorbing functional groups. For that, 8 different composts and their freeze-dried WEOMs were characterized by mid-IR transmission spectroscopy. Compositions of compost OM and of WEOM were characterized in terms of ratios (R) defined on the basis of both areas and heights of specific IR absorbance bands in relation to absorbance by aliphatic CH groups. A simple novel approach is suggested, whereby selective dissolution of compost OM components is quantified by relating the R values determined for WEOM to those associated with compost OM. Significant similarities of IR spectra found in a series of WEOMs (and, to a lesser extent, in a series of compost OMs) suggest significant contributions of OM carboxylic groups to various bands. IR absorbance of compost OM contributed by hydrophilic and, specifically, carboxyl and carboxylate groups, when related to absorbance by aliphatic CH groups, can be used for predicting the indices characterizing WEOM composition, such as IR absorbance-based R values and aromaticity estimated from specific UV absorbance.
Показать больше [+] Меньше [-]The quantification of bisphenols and their analogues in wastewaters and surface water by an improved solid-phase extraction gas chromatography/mass spectrometry method Полный текст
2020
Caban, Magda | Stepnowski, Piotr
The study focused on the application of GC in the quantitative analysis of bisphenols and their analogues (12 analytes), and the improvement of solid-phase extraction for the whole water analysis of complex water samples. The role of silylation in the qualitative and quantitative analysis of bisphenols was investigated. Partial degradation occurred for selected targets during hot injection with the presence of a silylation agent. A PSA (primary and secondary amines) sorbent placed on the top of the solid-phase extraction (SPE) column sorbent was found to be a matrix component trap, mostly for humic acids. The whole water analysis was performed by washing the filters with methanol and recycling the extract to the sample. The validation of SPE-GC/MS(SIM) gave limits of detection of 1–50 ng/L for ten target bisphenols with a method recovery of between 87 and 133%. The application of the method was tested by the analysis of wastewater sampled from three wastewater treatment plants located in Poland, and municipal surface waters. The only analytes found were BPA and BPS, within the range of 16–1465 ng/L and < MDL-1249 ng/L in wastewater, and 170–3113 ng/L and < MDL-1584 ng/L in surface water, respectively.
Показать больше [+] Меньше [-]Life cycle assessment of most widely adopted solar photovoltaic energy technologies by mid-point and end-point indicators of ReCiPe method Полный текст
2020
Rashedi, A. | Khanam, Taslima
The present article focuses on a cradle-to-grave life cycle assessment (LCA) of the most widely adopted solar photovoltaic power generation technologies, viz., mono-crystalline silicon (mono-Si), multi-crystalline silicon (multi-Si), amorphous silicon (a-Si) and cadmium telluride (CdTe) energy technologies, based on ReCiPe life cycle impact assessment method. LCA is the most powerful environmental impact assessment tool from a product perspective and ReCiPe is one of the most advanced LCA methodologies with the broadest set of mid-point impact categories. More importantly, ReCiPe combines the strengths of both mid-point-based life cycle impact assessment approach of CML-IA, and end-point-based approach of Eco-indicator 99 methods. Accordingly, the LCA results of all four solar PV technologies have been evaluated and compared based on 18 mid-point impact indicators (viz., climate change, ozone depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, human toxicity, photochemical oxidant formation, particulate matter formation, terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity, ionising radiation, agricultural land occupation, urban land occupation, natural land transformation, water depletion, metal depletion and fossil depletion), 3 end-point/damage indicators (viz., human health, ecosystems and cost increases in resource extraction) and a unified single score. The overall study has been conducted based on hierarchist perspective and according to the relevant ISO standards. Final results show that the CdTe thin-film solar plant carries the least environmental life cycle impact within the four PV technologies, sequentially followed by multi-Si, a-Si and mono-Si technology.
Показать больше [+] Меньше [-]Analysis of surface water reveals land pesticide contamination: an application for the determination of chlordecone-polluted areas in Guadeloupe, French West Indies Полный текст
2020
Rochette, Romain | Bonnal, Vincent | Andrieux, Patrick | Cattan, Philippe
Analysis of surface water reveals land pesticide contamination: an application for the determination of chlordecone-polluted areas in Guadeloupe, French West Indies Полный текст
2020
Rochette, Romain | Bonnal, Vincent | Andrieux, Patrick | Cattan, Philippe
In Guadeloupe, the use between 1972 and 1993 of chlordecone, an organochlorine insecticide, has permanently contaminated the island’s soil, thus contaminating the food chain at its very beginning. There is today a strong societal requirement for an improved mapping of the contaminated zones. Given the extent of the areas to be covered, carrying out soil tests on each plot of the territory would be a long and expensive process. In this article, we explore a method of demarcating polluted areas. The approach adopted consists in carrying out, using surface water analyses, a hydrological delimitation that makes it possible to distinguish contaminated watersheds from uncontaminated ones. The selection of sampling points was based on the spatial analysis of the actual and potential contamination data existing at the beginning of the study. The approach was validated by soil analyses, after having compared the contamination data of the watersheds with the soil contamination data of the plots within them. The study thus made it possible to highlight new contaminated areas and also those at risk of contamination and to identify the plots to be targeted as a priority during future analysis campaigns by State services.
Показать больше [+] Меньше [-]Analysis of surface water reveals land pesticide contamination: an application for the determination of chlordecone-polluted areas in Guadeloupe, French West Indies Полный текст
2020
Rochette, Romain | Bonnal, Vincent | Andrieux, Patrick | Cattan, Philippe | Agrosystèmes tropicaux (ASTRO) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Département Environnements et Sociétés (Cirad-ES) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH) ; Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | We would like to thank the French Government as well as the Guadeloupe Water Office which, as part of the National Chlordecone Action Plan III, co-funded this study, as well as the drafting of this article with the help of the European Union and the Guadeloupe Region (ERDF RIVAGE project)
International audience | In Guadeloupe, the use between 1972 and 1993 of chlordecone, an organochlorine insecticide, has permanently contaminated the island’s soil, thus contaminating the food chain at its very beginning. There is today a strong societal requirement for an improved mapping of the contaminated zones. Given the extent of the areas to be covered, carrying out soil tests on each plot of the territory would be a long and expensive process. In this article, we explore a method of demarcating polluted areas. The approach adopted consists in carrying out, using surface water analyses, a hydrological delimitation that makes it possible to distinguish contaminated watersheds from uncontaminated ones. The selection of sampling points was based on the spatial analysis of the actual and potential contamination data existing at the beginning of the study. The approach was validated by soil analyses, after having compared the contamination data of the watersheds with the soil contamination data of the plots within them. The study thus made it possible to highlight new contaminated areas and also those at risk of contamination and to identify the plots to be targeted as a priority during future analysis campaigns by State services.
Показать больше [+] Меньше [-]Physico-chemical and agronomic results of soil remediation by In Situ Chemical Reduction applied to a chlordecone-contaminated nitisol at plot scale in a French Caribbean banana plantation Полный текст
2020
Mouvet, C. (Christophe) | Collet, Bastien | Gaude, Jean-Marie | Rangon, Luc | Bristeau, Sébastien | Senergues, Mathlide | Lesueur Jannoyer, Magalie | Jestin, Alexandra | Hellal, Jennifer | Woignier, Thierry
Physico-chemical and agronomic results of soil remediation by In Situ Chemical Reduction applied to a chlordecone-contaminated nitisol at plot scale in a French Caribbean banana plantation Полный текст
2020
Mouvet, C. (Christophe) | Collet, Bastien | Gaude, Jean-Marie | Rangon, Luc | Bristeau, Sébastien | Senergues, Mathlide | Lesueur Jannoyer, Magalie | Jestin, Alexandra | Hellal, Jennifer | Woignier, Thierry
The In Situ Chemical Reduction (ISCR) process was tested in a nitisol in a French Caribbean banana plantation using five different soil amendments. The addition of 2.8% or 4.0% of Zero Valent Iron (ZVI; dw/dw, 2 different trial plots) in the 0–40-cm soil layer lowered the initial chlordecone (CLD) concentration by up to 74% or 69% in 37 days or 94 days, with 75% of the decrease achieved after only 21 or 24 days of treatment depending on the trial plot. The addition of commercially available Daramend® was also tested by applying the 6% dose (dw/dw) recommended by the manufacturer and using either the regular alfalfa-based product or a bagasse-based product specifically formulated for the study. Both significantly lowered CLD concentrations, but to a lesser extent than with the ZVI-only amendment. A bagasse-ZVI mixture prepared on site produced results slightly better than the two Daramend®. The percentage decreases in CLD concentrations were correlated with the negative redox potentials achieved. In all the trial plots, dechlorinated transformation products appeared in the soil and soil water as the CLD concentrations decreased, with H atoms replacing up to 4 and 7 of the 10 Cl atoms, respectively. None of these degradation products appeared to accumulate in the soil or soil water during the treatment. Instead, the reverse occurred, with an overall downward trend in their concentrations over time. The effects of ISCR treatment on agronomic and human health–related parameters were measured in three different crops. The radishes produced with some treatments were visually of lower quality or smaller in size than those grown in the control plots. Lower yields were observed for the cucumbers and sweet potatoes grown after applying the bagasse-based amendments. Mortality among cucumber seedlings was observed after treatment with ZVI only. Simple operational solutions should suffice to remedy these negative agronomic effects. As regards human health–related effects, the CLD concentrations in radishes grown with three of the amendments were significantly lower than in the two control plots and well below the maximum residue level (MRL), which was substantially exceeded in the radishes grown on untreated soil. For cucumbers, the treatments with regular Daramend® and with a local bagasse-ZVI mixture produced fruits with CLD below the MRL and also below the concentrations in one of the two control plots. As for the sweet potatoes, adding a bagasse-ZVI mixture had a significant positive effect by decreasing contamination below the levels in the two control plots and below the MRL.
Показать больше [+] Меньше [-]Physico-chemical and agronomic results of soil remediation by In Situ Chemical Reduction applied to a chlordecone-contaminated nitisol at plot scale in a French Caribbean banana plantation Полный текст
2020
Mouvet, Christophe | Collet, Bastien | Gaude, Jean-Marie | Rangon, Luc | Bristeau, Sébastien | Senergues, Mathilde | Lesueur-Jannoyer, Magalie | Jestin, Alexandra | Hellal, Jennifer | Woignier, Thierry
The In Situ Chemical Reduction (ISCR) process was tested in a nitisol in a French Caribbean banana plantation using five different soil amendments. The addition of 2.8% or 4.0% of Zero Valent Iron (ZVI; dw/dw, 2 different trial plots) in the 0–40-cm soil layer lowered the initial chlordecone (CLD) concentration by up to 74% or 69% in 37 days or 94 days, with 75% of the decrease achieved after only 21 or 24 days of treatment depending on the trial plot. The addition of commercially available Daramend® was also tested by applying the 6% dose (dw/dw) recommended by the manufacturer and using either the regular alfalfa-based product or a bagasse-based product specifically formulated for the study. Both significantly lowered CLD concentrations, but to a lesser extent than with the ZVI-only amendment. A bagasse-ZVI mixture prepared on site produced results slightly better than the two Daramend®. The percentage decreases in CLD concentrations were correlated with the negative redox potentials achieved. In all the trial plots, dechlorinated transformation products appeared in the soil and soil water as the CLD concentrations decreased, with H atoms replacing up to 4 and 7 of the 10 Cl atoms, respectively. None of these degradation products appeared to accumulate in the soil or soil water during the treatment. Instead, the reverse occurred, with an overall downward trend in their concentrations over time. The effects of ISCR treatment on agronomic and human health–related parameters were measured in three different crops. The radishes produced with some treatments were visually of lower quality or smaller in size than those grown in the control plots. Lower yields were observed for the cucumbers and sweet potatoes grown after applying the bagasse-based amendments. Mortality among cucumber seedlings was observed after treatment with ZVI only. Simple operational solutions should suffice to remedy these negative agronomic effects. As regards human health–related effects, the CLD concentrations in radishes grown with three of the amendments were significantly lower than in the two control plots and well below the maximum residue level (MRL), which was substantially exceeded in the radishes grown on untreated soil. For cucumbers, the treatments with regular Daramend® and with a local bagasse-ZVI mixture produced fruits with CLD below the MRL and also below the concentrations in one of the two control plots. As for the sweet potatoes, adding a bagasse-ZVI mixture had a significant positive effect by decreasing contamination below the levels in the two control plots and below the MRL.
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