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Biochemical potential evaluation and kinetic modeling of methane production from six agro-industrial wastewaters in mixed culture Texte intégral
2021
Sales Morais, Naassom Wagner | Coelho, Milena Maciel Holanda | Silva, Amanda de Sousa e | Silva, Francisco Schiavon Souza | Ferreira, Tasso Jorge Tavares | Pereira, Erlon Lopes | dos Santos, André Bezerra
Methane (CH₄) production from anaerobic digestion of solid and liquid agro-industrial wastes is an attractive strategy to meet the growing need for renewable energy sources and promote environmentally appropriate disposal of organic wastes. This work aimed at determining the CH₄ production potential of six agro-industrial wastewaters (AWW), evaluating the most promising for methanization purposes. It also aims to provide kinetic parameters and stoichiometric coefficients of CH₄ production and define which kinetic models are most suitable for simulating the CH₄ production of the evaluated substrates. The AWW studied were swine wastewater (SW), slaughterhouse wastewater (SHW), dairy wastewater (DW), brewery wastewater (BW), fruit processing wastewater (FPW), and residual glycerol (RG) of biodiesel production. RG was the substrate that showed the highest methanization potential. Exponential kinetic models can be efficiently applied for describing CH₄ production of more soluble substrates. On the other hand, logistic models were more suitable to predict the CH₄ production of more complex substrates.
Afficher plus [+] Moins [-]Towards understanding the effects of oceanic plastic pollution on population growth for a South American fur seal (Arctocephalus australis australis) colony in Chile Texte intégral
2021
Perez-Venegas, Diego Joaquín | Valenzuela-Sánchez, Andrés | Montalva, Felipe | Pavés, Héctor | Seguel, Mauricio | Wilcox, Chris | Galbán-Malagón, Cristóbal
Entanglement of pinnipeds with plastic debris is an emerging conservation and animal welfare issue worldwide. However, the origins and long-term population level consequences of these entanglements are usually unknown. Plastic entanglement could produce a combination of wounds, asphyxiation, or inability to feed that results in the death of a certain percentage of individuals from the total population. In this research, we report on the consequent effect of plastic entanglement on population growth demographics in a South American fur seal (Arctocephalus australis australis) colony on Guafo Island, southern Chile. Using a stochastic matrix population model structured according to age and sex, and assuming an otherwise stable population, we explored population growth rates under five scenarios with differing rates of entanglement: A) a zero rate of plastic entanglement, B) entanglement rates (number of entangled individuals as a proportion of the total number of individuals) as observed in our study population (overall entanglement ratio of 1.2 × 10⁻³); and for the other scenarios, entanglement ratios as reported in the literature for other pinniped colonies around the world: C) 3.04 × 10⁻³, D) 4.42 × 10⁻², and E) 8.39 × 10⁻². Over the 30 years forecasting period and starting with a population size of ∼2950 individuals, the population growth rate was lower under all scenarios with rates of entanglement greater than zero (scenarios B-E). In comparison with scenario A, at the end of the 30-year period forecasted, we calculated a projected decrease in population size of between 20.34% (scenario B) and 91.38% (scenario E). These results suggest that even the lowest levels of entanglement in pinnipeds as reported in the literature might have significant effects over time on population-level dynamics. Our research offers potential insight when devising policy for the management and limitation of plastic pollution in the oceans, and indeed for the conservation and management policy of affected marine species. Furthermore, whilst there are some limitations to our methodology, it offers a straightforward and potentially useful approach for the standardized prediction of impacts at a population level of different rates of plastic pollution and entanglement and could be applied in distinct populations of the same species around the world.
Afficher plus [+] Moins [-]Combined influences of transgenerational effects, temperature and insecticide on the moth Spodoptera littoralis Texte intégral
2021
Massot, Manuel | Bagni, Thibaut | Maria, Annick | Couzi, Philippe | Drozdz, Thomas | Malbert-Colas, Aude | Maïbèche, Martine | Siaussat, David
Combined influences of transgenerational effects, temperature and insecticide on the moth Spodoptera littoralis Texte intégral
2021
Massot, Manuel | Bagni, Thibaut | Maria, Annick | Couzi, Philippe | Drozdz, Thomas | Malbert-Colas, Aude | Maïbèche, Martine | Siaussat, David
Climate warming is expected to impact the response of species to insecticides. Recent studies show that this interaction between insecticides and temperature can depend on other factors. Here, we tested for the influence of transgenerational effects on the Insecticide × Temperature interaction in the crop pest moth Spodoptera littoralis. Specifically, we analysed reaction norms among experimental clutches based on a split-plot design crossing the factors temperature, insecticide and clutch. The study was performed on 2280 larvae reared at four temperatures (23, 25, 27 and 29 °C), and their response to the insecticide deltamethrin (three concentrations and a control group) was tested. Temperature had a global influence with effects on larval survival, duration of development, pupal body mass, and significant reaction norms of the clutches for temperature variations of only 2 °C. In addition to the expected effect of deltamethrin on mortality, the insecticide slightly delayed the development of S. littoralis, and the effects on mortality and development differed among the clutches. Projection models integrating all the observed responses illustrated the additive effects of deltamethrin and temperature on the population multiplication rate. Variation in the response of the clutches showed that transgenerational effects influenced the impact of insecticide and temperature. Although no evidence indicated that the Insecticide × Temperature interaction depended on transgenerational effects, the studies on the dependence of the Insecticide × Temperature interaction on other factors continue to be crucial to confidently predict the combined effects of insecticides and climate warming.
Afficher plus [+] Moins [-]Combined influences of transgenerational effects, temperature and insecticide on the moth Spodoptera littoralis Texte intégral
2021
Massot, Manuel | Bagni, Thibaut | Maria, Annick | Couzi, Philippe | Drozdz, Thomas | Malbert-Colas, Aude | 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 | Climate warming is expected to impact the response of species to insecticides. Recent studies show that this interaction between insecticides and temperature can depend on other factors. Here, we tested for the influence of transgenerational effects on the Insecticide x Temperature interaction in the crop pest moth Spodoptera littoralis. Specifically, we analysed reaction norms among experimental clutches based on a split-plot design crossing the factors temperature, insecticide and clutch. The study was performed on 2280 larvae reared at four temperatures (23, 25, 27 and 29°C), and their response to the insecticide deltamethrin (three concentrations and a control group) was tested. Temperature had a global influence with effects on larval survival, duration of development, pupal body mass, and significant reaction norms of the clutches for temperature variations of only 2°C. In addition to the expected effect of deltamethrin on mortality, the insecticide slightly delayed the development of S. littoralis, and the effects on mortality and development differed among the clutches. Projection models integrating all the observed responses illustrated the additive effects of deltamethrin and temperature on the population multiplication rate. Variation in the response of the clutches showed that transgenerational effects influenced the impact of insecticide and temperature. Although no evidence indicated that the Insecticide x Temperature interaction depended on transgenerational effects, the studies on the dependence of the Insecticide x Temperature interaction on other factors continue to be crucial to confidently predict the combined effects of insecticides and climate warming.
Afficher plus [+] Moins [-]Polychlorinated biphenyl quinone regulates MLKL phosphorylation that stimulates exosome biogenesis and secretion via a short negative feedback loop Texte intégral
2021
Peng, Lu | Wang, Yawen | Yang, Bingwei | Qin, Qi | Song, Erqun | Song, Yang
Polychlorinated biphenyls (PCBs) are one of the most refractory organic environmental pollutants that ubiquitous existence in nature. Due to the polymorphism of their metabolic pathway and corresponding downstream metabolites, PCBs’ toxicities are complicated and need extended investigation. In the present study, we discovered a novel regulatory mechanism of PCB quinone metabolite-driven programmed cell death (PCD), namely, necroptosis. We first confirmed that PCB quinone induces cancerous HeLa and MDA-MB-231 cells necroptosis via the phosphorylation of mixed lineage kinase domain-like MLKL (p-MLKL). Then, we found that PCB quinone-stimulated p-MLKL enhances exosome biogenesis and secretion. Exosome interacts with p-MLKL and releases p-MLKL to the outside of the cell, and ultimately alleviating PCB quinone-induced necroptosis. The inhibition of exosome secretion by GW4869 significantly elevated necroptotic level, indicating the establishment of a short negative feedback loop of MLKL-exosome secretion upon PCB quinone challenge. Since exosome-mediated signaling showed great implications in various human diseases, this work may provide a new mechanism for PCBs-associated toxicity.
Afficher plus [+] Moins [-]PAHs in an urban-industrial area: The role of lichen transplants in the detection of local and study area scale patterns Texte intégral
2021
Lucadamo, L. | Gallo, L. | Corapi, A.
Spatial variation of the levels of polycyclic aromatic hydrocarbons (PAHs) was evaluated within an urban-industrial district where the main anthropogenic pressures are a 15 MW biomass power plant (BPP) and road traffic. The use of a high-density lichen transplant network and wind quantitative relationships made it possible to perform a hierarchical analysis of contamination. Combined uni-bi and multivariate statistical analyses of the resulting databases revealed a dual pattern. In its surroundings (local scale), the BPP affected the bioaccumulation of fluoranthene, pyrene and total PAHs, although a confounding effect of traffic (mostly petrol/gasoline engines) was evident. Spatial variation of the rate of diesel vehicles showed a significant association with that of acenaphthylene, acenaphthene, fluorene, anthracene and naphthalene. The series of high-speed wind values suggests that wind promotes diffusion rather than dispersion of the monitored PAHs. At the whole study area scale, the BPP was a source of acenaphthylene and acenaphthene, while diesel vehicles were a source of acenaphthylene. PAHs contamination strongly promotes oxidative stress (a threefold increase vs pre-exposure levels) in lichen transplants, suggesting a marked polluting effect of anthropogenic sources especially at the expense of the mycobiont. The proposed monitoring approach could improve the apportionment of the different contributions of point and linear anthropogenic sources of PAHs, mitigating the reciprocal biases affecting their spatial patterns.
Afficher plus [+] Moins [-]Factors affecting the exposure to physicochemical and microbiological pollutants in vehicle cabins while commuting in Lisbon Texte intégral
2021
Buitrago, N.D. | Savdie, J. | Almeida, S.M. | Verde, S Cabo
Commuters are exposed to a variety of physicochemical and microbiological pollutants that can lead to adverse health effects. This study aims to evaluate the indoor air quality (IAQ) in cars, buses and trains in Lisbon, to estimate inhaled doses while commuting and to evaluate the impacts of cleaning and ventilation on the IAQ. Particulate matter with diameter lower than 1, 2.5 and 10 μm (PM₁, PM₂.₅ and PM₁₀), black carbon (BC), carbon monoxide (CO), carbon dioxide (CO₂) volatile organic compounds (VOCs), formaldehyde (CH₂O) and total airborne bacteria and fungi were measured and bacterial isolates were identified. Results showed that the type of ventilation is the main factor affecting the IAQ in vehicle cabins. Under the fan off condition, the concentration of BC was lower, but the concentration of gases such as CO₂, CO and VOC tended to accumulate rapidly. When the ventilation was used, the coarse particles were filtered originating the decrease of indoor concentrations. Commuters travelling in trains received the lowest dose for all chemical pollutants, except VOC, mainly because railways are further away from the direct vehicular emissions. Commuters travelling in cars without ventilation received the highest inhaled dose for almost all pollutants despite having the lowest travel duration. Airborne microbiota was highly affected by the occupancy of the vehicles and therefore, the fungi and bacterial loads were higher in trains and buses. Most of the isolated species were human associated bacteria and some of the most abundant species have been linked to respiratory tract infections.
Afficher plus [+] Moins [-]Respiratory mortality associated with ozone in China: A systematic review and meta-analysis Texte intégral
2021
Zhang, Yifan | Ma, Yuxia | Feng, Fengliu | Cheng, Bowen | Shen, Jiahui | Wang, Hang | Jiao, Haoran | Li, Mingji
This systematic review and meta-analysis was performed to obtain updated evidence regarding the short-term effect of ozone on respiratory mortality in China. We systematically searched the Embase, PubMed, Scopus, Web of Science, China National Knowledge Internet, and Wanfang databases for relevant studies. After screening based on the inclusion criteria, 12 studies with 19 estimates were selected for further meta-analysis. The results revealed that respiratory mortality significantly increased by 0.55% (95% confidence interval: 0.24%–0.85%; Q = 39.47, I² = 54.4%, P = 0.002, tau² < 10⁻⁵) for every 10-μg/m³ increase in the maximum 8-h average concentration of ozone. Furthermore, differences in combined estimates were observed between various regions and lag structures. The combined effect of single-day lags was generally larger than that of multiday lags; the estimate of mortality for the population in the north was larger than that for the population in the south. The sensitivity analysis demonstrated that the main findings were stable; funnel plots with Egger’s and Begg’s tests indicated no significant publication bias in our analysis.
Afficher plus [+] Moins [-]Significant influence of phosphorus resources on the growth and alkaline phosphatase activities of Microcystis aeruginosa Texte intégral
2021
Xie, En | Su, Yuping | Deng, Songqiang | Kontopyrgou, Maria | Zhang, Dayi
It is well-accepted that phosphorus, particularly orthophosphate, is a determinant factor in aquatic eutrophication. However, numerous kinds of phosphorus sources exist in real world scenario, and limited studies have characterized the pairwise relationships among abundant different phosphorus sources and the physiological behaviour of algae. The present study developed a high-throughput assay to investigate the effects of 59 different phosphorus sources (equal initial concentration of total phosphorus) on the growth and alkaline phosphatase (AKP) activities of Microcystis aeruginosa, a model cyanobacteria whose predominance holds sway in lake eutrophication. M. aeruginosa cultivated with nucleoside monophosphates (NMPs) had higher growth, relative AKP activities and residual orthophosphate, which were positively intercorrelated. Oppositely, non-NMPs cultivation of M. aeruginosa led to negative relationships between the relative AKP activities and their growth or residual orthophosphate. These results indicated distinct mechanisms for M. aeruginosa to utilize different phosphorus sources in real-world scenario, and both phosphorus source and content are determinant factors on the growth and physiological behaviour of M. aeruginosa. Given the complicated and vast phosphorus pool in the natural environment, phosphorus resources might significantly alter the abundance and physiological behaviour of M. aeruginosa and other bloom-forming algae, then influence the phytoplanktonic community structure and affect the possibility and intensity of algal bloom. Our work hints the underestimation of the restriction factors in lake eutrophication and provides a new tool to study the driven forces of phytoplanktonic community dynamics as phosphorus from both internal and external sources.
Afficher plus [+] Moins [-]Effects of exposure to prothioconazole and its metabolite prothioconazole-desthio on oxidative stress and metabolic profiles of liver and kidney tissues in male mice Texte intégral
2021
Meng, Zhiyuan | Tian, Sinuo | Sun, Wei | Liu, Li | Yan, Sen | Huang, Shiran | Zhu, Wentao | Zhou, Zhiqiang
Prothioconazole (PTC), a popular agricultural fungicide, and its main metabolite prothioconazole-desthio (PTCd) are receiving great attention due to their toxicological effects in the non-target organisms. This study investigated their dosage-dependent (1 and 5 mg/kg BW/day) toxicological effects on oxidative stress and metabolic profiles of liver and kidney tissues using male mice. PTC and PTCd significantly inhibited the growth phenotype including body weights gain, liver and kidney indices. Furthermore, these effects were deeply investigated using the biomarkers of oxidative stress, and metabolomics. Notably, these effects were dose and tissue-dependent. Specifically, the more serious impacts involving oxidative stress and metabolic disorders were observed in the high concentration treatment groups. Also, the liver tissue was more severely affected than the kidney tissue. Lastly, the change in oxidative stress biomarkers and metabolomics profile revealed that PTCd induced more severe toxic effects than the parent compound PTC. In brief, these results indicate that exposure to PTC and PTCd could cause potential health risks in mammals.
Afficher plus [+] Moins [-]Exposure to fine particulate matter-bound polycyclic aromatic hydrocarbons, male semen quality, and reproductive hormones: The MARCHS study Texte intégral
2021
Chen, Qing | Wang, Furong | Yang, Huan | Wang, Xiaogang | Zhang, Aihua | Ling, Xi | Li, Lianbing | Zou, Peng | Sun, Lei | Huang, Linping | Chen, Hongqiang | Ao, Lin | Liu, Jinyi | Cao, Jia | Zhou, Niya
Exposure to outdoor fine particulate matter (PM₂.₅)-bound polycyclic aromatic hydrocarbons (PAHs) is linked to reproductive dysfunction. However, it is unclear which component of PAHs is responsible for the adverse outcomes. In the Male Reproductive Health in Chongqing College Students (MARHCS) cohort study, we measured the exposure levels of 16 PAHs by collecting air PM₂.₅ particles and assessed eight PAHs metabolites from four parent PAHs, including naphthalene, fluorene, phenanthrene, and pyrene in urine samples. We investigated compositional profiles and variation characteristics for 16 PAHs in PM₂.₅, and then assessed the association between PAHs exposure and semen routine parameters, sperm chromatin structure, and serum hormone levels in 1452 samples. The results showed that naphthalene (95% CI: −17.989, −8.101), chrysene (95% CI: −64.894, −47.575), benzo[a]anthracene (95% CI: −63.227, −45.936) and all the high molecular weight (HMW) PAHs in PM₂.₅ were negatively associated with sperm normal morphology. Most of the low molecular weight (LMW) PAHs, such as acenaphthylene, fluorene, phenanthrene, fluoranthene, pyrene, chrysene, benzo[a]anthracene, ∑LMW PAHs and ∑16 PAHs, were correlated with increased sperm motility (all corrected P < 0.05). On the other hand, sperm normal morphology was all negatively associated with urinary metabolites of ∑OH-Nap (95% CI: −5.611, −0.536), ∑OH-Phe (95% CI: −5.741, −0.957), and ∑OH-PAHs (95% CI: −5.274, −0.361). Urinary concentrations of ∑OH-PAHs were found to be negatively associated with sperm high DNA stainability (HDS) (P = 0.023), while ∑OH-Phe were negatively associated with serum testosterone level and sperm HDS (P = 0.004). Spearman correlation analysis showed that except for the urinary OH-Nap metabolites, the rest of the urinary OH-PAHs metabolites were negatively correlated with their parent PAHs in air. The results of this study suggest that various PAHs’ components may affect reproductive parameters differently. Inhalation of PAHs in air, especially HMW PAHs, may be a potential risk factor for male reproductive health.
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