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Fish community diversity in a coastal zone at southeastern Gulf of California, Mexico Texte intégral
2022
Although the southeast region of the Gulf of California has a high fish diversity, due to the high biological productivity, the coastal area of Nayarit has few studies in this regard. The main objective of this work is to describe the variability of the structure of the ichthyofauna in the coastal zone of Nayarit during an annual cycle. Biological samples were collected at 10 stations during February, May, July, and December 2014. The temperature, depth, salinity, and organic material and carbonates in sediments were also recorded. The analysis of diversity includes three facets: ecological, taxonomic, and functional. A total of 82 species belonging to 56 genera, 31 families, 11 orders, and two classes were identified. The most abundant species included Selene peruviana, Stellifer wintersteenorum, Cathorops sp., and Larimus argenteus. Of the total of identified species, 62% were considered as rare according to their abundance and frequency. Although the environmental variables analyzed were variable, all diversity indices did not reveal an evident spatio-seasonal pattern. Likewise, most values of average taxonomic distinctness presented the expected values. However, some values showed a low taxonomic diversity. The indices of functional diversity showed a stable functional richness and redundancy in the attributes of the species.
Afficher plus [+] Moins [-]Instrumental and bioanalytical assessment of pharmaceuticals and hormone-like compounds in a major drinking water source—wastewater receiving Zayandeh Rood river, Iran Texte intégral
2022
Zayandeh Rood river is the most important river in central Iran supplying water for a variety of uses including drinking water for approximately three million inhabitants. The study aimed to investigate the quality of water concerning the presence of pharmaceutical active compounds (PhACs) and hormonelike compounds, which have been only poorly studied in this region. Sampling was performed at seven sites along the river (from headwater sites to downstream drinking water source, corresponding drinking water, and treated wastewater) affected by wastewater effluents, specific drought conditions, and high river-water demand. The targeted and nontargeted chemical analyses and in vitro bioassays were used to evaluate the presence of PhACs and hormonelike compounds in river water. In the samples, 57 PhACs and estrogens were detected with LC-MS/MS with the most common and abundant compounds valsartan, carbamazepine, and caffeine present in the highest concentrations in the treated wastewater in the concentrations of 8.4, 19, and 140 μg/L, respectively. A battery of in vitro bioassays detected high estrogenicity, androgenicity, and AhR-mediated activity (viz., in treated wastewater) in the concentrations 24.2 ng/L, 62.2 ng/L, and 0.98 ng/L of 17β-estradiol, dihydrotestosterone and 2,3,7,8-TCDD equivalents, respectively. In surface water samples, estrogenicity was detected in the range of <0.42 (LOD) to 1.92 ng/L of 17β-estradiol equivalents, and the drinking water source contained 0.74 ng/L of 17β-estradiol equivalents. About 19% of the estrogenicity could be explained by target chemical analyses, and the remaining estrogenicity can be at least partially attributed to the potentiation effect of detected surfactant residues. Drinking water contained several PhACs and estrogens, but the overall assessment suggested minor human health risk according to the relevant effect-based trigger values. To our knowledge, this study provides some of the first comprehensive information on the levels of PhACs and hormones in Iranian waters.
Afficher plus [+] Moins [-]Evaluating the aerobic xylene-degrading potential of the intrinsic microbial community of a legacy BTEX-contaminated aquifer by enrichment culturing coupled with multi-omics analysis: uncovering the role of Hydrogenophaga strains in xylene degradation Texte intégral
2022
Banerjee, Sinchan | Bedics, Anna | Harkai, Péter | Kriszt, Balázs | Alpula, Nagaraju | Táncsics, András
To develop effective bioremediation strategies, it is always important to explore autochthonous microbial community diversity using substrate-specific enrichment. The primary objective of this present study was to reveal the diversity of aerobic xylene-degrading bacteria at a legacy BTEX-contaminated site where xylene is the predominant contaminant, as well as to identify potential indigenous strains that could effectively degrade xylenes, in order to better understand the underlying facts about xylene degradation using a multi-omics approach. Henceforward, parallel aerobic microcosms were set up using different xylene isomers as the sole carbon source to investigate evolved bacterial communities using both culture-dependent and independent methods. Research outcome showed that the autochthonous community of this legacy BTEX-contaminated site has the capability to remove all of the xylene isomers from the environment aerobically employing different bacterial groups for different xylene isomers. Interestingly, polyphasic analysis of the enrichments disclose that the community composition of the o-xylene-degrading enrichment community was utterly distinct from that of the m- and p-xylene-degrading enrichments. Although in each of the enrichments Pseudomonas and Acidovorax were the dominant genera, in the case of o-xylene-degrading enrichment Rhodococcus was the main player. Among the isolates, two Hydogenophaga strains, belonging to the same genomic species, were obtained from p-xylene-degrading enrichment, substantially able to degrade aromatic hydrocarbons including xylene isomers aerobically. Comparative whole-genome analysis of the strains revealed different genomic adaptations to aromatic hydrocarbon degradation, providing an explanation on their different xylene isomer-degrading abilities.
Afficher plus [+] Moins [-]Synchronous Efficient Reduction of Cr (VI) and Removal of Total Chromium by Corn Extract / Fe (III) System Texte intégral
2022
Sun, He | Hua, Yuduo | Zhao, Yongsheng
In this study, a cost-effective and environmentally friendly composite system for the remediation of Cr (VI)-polluted groundwater was developed. The system of simultaneous reduction of Cr (VI) and precipitation of Cr (III) was innovatively constructed, using corncob extract as electron donor and Fe (III) as strengthening reagent. In the process of the total chromium removal, the addition of alkaline substances was not required, when pH ≤ 4 it showed an optimal reduction of Cr (VI). In addition, the removal rate of total chromium reached 88% within 120 min. To understand the mechanism of this system, we characterized the corn extract and particulate matter before and after the reaction. Fourier transform infrared spectroscopy and gas chromatography–mass spectrometry suggested that alcohols, phenols, and aldehydes provided the electrons that were required to reduce Cr (VI). As an electron shuttle, Fe (III) improved the efficiency of electron transfer, and Fe (II) and nano-zerovalent iron (nZVI) particles were formed during this process. X-ray diffraction and transmission electron microscopy analyses showed that FeOCl was formed under the action of the plant extract and adsorbed Cr (III), thus reducing total chromium. Both nZVI and FeOCl were covered with a layer of paste cap, which maintained the stability of their physical and chemical properties. The regulation of pH during the repair process was not required, and the cost of the process was significantly reduced. Therefore, this technology provides a new strategy for the in situ remediation of Cr (VI) pollution in groundwater.
Afficher plus [+] Moins [-]Can technology-driven cross-border mergers and acquisitions promote green innovation in emerging market firms? Evidence from China Texte intégral
2022
Li, Jingjing
Emerging markets face severe ecological and environmental problems in periods of economic and political transition. The existing literature analyses the impact of technology on environmental benefits and the role of technology on the green innovation of enterprises, mostly from the perspective of technology spillover in enterprises in mature markets. Based on a sample of 229 Chinese cross-border mergers and acquisitions (M&As), this paper explores the role of technology-driven cross-border M&As (TDC M&As) in green innovation, finding that TDC M&As have a significant promoting effect on green innovation. A higher degree of ownership concentration positively promotes the relationship between TDC M&As and green innovation in the enterprise. This paper divides enterprises into state-owned enterprises (SOEs) and political connection enterprises, with the nature of SOEs negatively affecting the relationship between TDC M&As and green innovation, the nature of political connections significantly promoting the relationship. Similarly, formal institutional distance negatively interacts with TDC M&As to affect the green innovation of enterprises, while informal distance interacts positively with TDC M&As. This paper has important implications for emerging market enterprises in realising the transformation of the mode of economic growth and achieving harmonious development between enterprises and the environment.
Afficher plus [+] Moins [-]Correlation between anxiety and resilience of healthcare workers during COVID-19 pandemic in the southwest of Iran Texte intégral
2022
Rayani, Saba | Rayani, Mohammad | Najafi-Sharjabad, Fatemeh
The pandemic of COVID-19 has had a negative impact on healthcare providers. Resilience is thought to protect against mental illnesses and to help people cope with stress more effectively. The purpose of this research is to determine the relationship between resilience and anxiety in healthcare workers during the COVID-19 pandemic. A cross-sectional online survey was carried out on 184 eligible healthcare workers recruited from health centers in Bushehr and Borazjan cities. Data collection was performed using standard questionnaires that consist of sociodemographic and COVID-19-related information, the Corona Disease Anxiety Scale, and the Connor-Davidson Resilience Scale. The data were analyzed using SPSS software and descriptive statistics. The Mann–Whitney U test, Independet Sample t-test, Kruskal–Wallis , and Spearman correlation test were applied for analyzing data. Statistical significance was set at a P-value of < 0.05. The age mean of the participants was 35.54 ± 7.11, and 40% of them experienced moderate and high levels of anxiety. Significant negative relationship was found between anxiety and resilience (r = − 0.211, p = 0.032). Those who experienced death from COVID-19 in family or friends were more anxious than their counterparts (p = 0.004). This study showed more than one-third of the participants experienced moderate and high levels of anxiety in response to the COVID-19 pandemic. Anxiety was found to be related to resilience, and the greater the resilience, the lower the overall anxiety score. In policy development, this can be used to improve the resilience of healthcare workers and prevent mental health illnesses.
Afficher plus [+] Moins [-]Intelligent modeling and optimization of environmentally friendly green enzymatic deinking of printed paper Texte intégral
2022
Ataeefard, Maryam | Tilebon, Seyyed Mohamad Sadati | Etezad, Seyed Masoud | Mahdavi, Saeed
Nowadays, the paper industry supplies its required fibers either from primary fibers, including wood and plants, or waste papers, called secondary fibers. One of the most challenging recycling processes is deinking of papers digitally printed with electrophotographic ink. In order to produce optically high-quality paper from recycled waste papers, deinking step is required at the desired levels. In this work, the environmentally friendly green enzymatic deinking of printed paper was modeled and optimized via an innovative approach called artificial intelligence method. The effect of treatment temperature, treatment time, and enzyme dosage on mechanical properties (tensile and burst strengths) as well as optical properties (whiteness and brightness) of handsheet was investigated. The developed code can appropriately learn the non-linear behavior of deinking process, and make decisions according to the pattern constructed intelligently. Finally, multi-objective optimization at the specified treatment temperature, treatment time, and enzyme dosage was performed to identify the best conditions for enzyme-deinked handsheet (maximized mechanical and optical properties).
Afficher plus [+] Moins [-]Amelioration of aluminum-induced hepatic and nephrotoxicity by Premna odorata extract is mediated by lowering MMP9 and TGF-β gene alterations in Wistar rat Texte intégral
2022
Ahmed, Walaa M. S. | Ibrahim, Marwa A. | Helmy, Nermeen A. | ElKashlan, Akram M. | Elmaidomy, Abeer H. | Zaki, Amr R.
This study aims to investigate the effect of Premna odorata (P. odorata) (Lamiaceae) on the hepatic and nephrotoxicity induced by aluminum chloride (AlCl₃) in rat. Wistar male rats were equally classified into four groups: control, P. odorata extract (500 mg/kg B.W.), AlCl₃ (70 mg/kg B.W.), and P. odorata extract plus AlCl₃ groups. All treatments were given orally for 4 weeks. Serum transaminases and some biochemical parameters, hepatic and renal antioxidant/oxidant biomarker; tumor necrosis factor-α (TNF-α); matrix metalloproteinase (MMP9) and transforming growth factor-β (TGF-β) mRNA expression; histopathological examination of the liver, and kidneys were investigated. The obtained results revealed that AlCl₃ significantly increased the activities of serum aspartate transaminase, alanine transaminase, and alkaline phosphatase as well as produced a significant increase in total cholesterol, triglyceride, urea, and creatinine concentrations, while there were no changes observed in the total protein, albumin, and globulin concentrations. Also, aluminum administration significantly decreased the reduced glutathione content and increased the catalase activity, malondialdehyde, and TNF-α concentrations in the liver and kidney tissue. Moreover, AlCl₃ results in congestion, degeneration, and inflammation of the liver and kidney tissue. Co-treatment of P. odorata extract with AlCl₃ alleviated its harmful effects on the previous parameters and reduced the histopathological alterations induced by AlCl₃. Therefore, Premna odorata may have a potent protective effect against oxidative stress induced by Al toxicity through downregulation of MMP9 and TGF-β gene expression.
Afficher plus [+] Moins [-]The role of private investment in ICT on carbon dioxide emissions (CO2) mitigation: do renewable energy and political risk matter in Morocco? Texte intégral
2022
Khan, Yasir | Oubaih, Hana | Elgourrami, Fatima Zahra
The present study proposed the relationship among private investment in information and communication technology (ICT), carbon emissions (CO₂), renewable energy, political risk, and economic growth over the period of 1985–2020 in Morocco. The dynamic ARDL simulations (ARDL) model suggests that private partnership in ICT plays a significant role in abating CO₂ emissions, the adaptation of renewable energy is a key contributor in CO₂ degradation, while economic growth shows a positive and significant association with CO₂ emissions, indicating that economic growth increases CO₂ emissions. The study also analyzed political risk in the study region, which indicates that low political risk mitigates CO₂ emissions in Morocco. The findings provide significant enlightenment to acknowledge the importance of private partnership in ICT for the purpose to decarbonize CO₂ emissions, and adopting the use of renewable energy. The findings also suggest that a stable political system is inventible towards low-carbon development.
Afficher plus [+] Moins [-]Appraisal of kinetin spraying strategy to alleviate the harmful effects of UVC stress on tomato plants Texte intégral
2022
Dawood, Mona F. A. | Abu-Elsaoud, Abdelghafar M. | Sofy, Mahmoud R. | Mohamed, Heba I. | Soliman, Mona H.
Increasing ultraviolet (UV) radiation is causing oxidative stress that accounts for growth and yield losses in the present era of climate change. Plant hormones are useful tools for minimizing UV-induced oxidative stress in plants, but their putative roles in protecting tomato development under UVC remain unknown. Therefore, we investigated the underlying mechanism of pre-and post-kinetin (Kn) treatments on tomato plants under UVC stress. The best dose of Kn was screened in the preliminary experiments, and this dose was tested in further experiments. UVC significantly decreases growth traits, photosynthetic pigments, protein content, and primary metabolites (proteins, carbohydrates, amino acids) but increases oxidative stress biomarkers (lipid peroxidation, lipoxygenase activity, superoxide anion, hydroxyl radical, and hydrogen peroxide) and proline content. Treatment of pre-and post-kinetin spraying to tomato plants decreases UVC-induced oxidative stress by restoring the primary and secondary metabolites’ (phenolic compounds, flavonoids, and anthocyanins) status and upregulating the antioxidant defense systems (non-enzymatic antioxidants as ascorbate, reduced glutathione, α-tocopherol as well as enzymatic antioxidants as superoxide dismutase, catalase, ascorbate peroxidase, glutathione peroxidase, glutathione-S-transferase, and phenylalanine ammonia-lyase). Thus, the application of Kn in optimum doses and through different modes can be used to alleviate UVC-induced negative impacts in tomato plants.
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