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Bisphenol S exposure affects gene expression related to intestinal glucose absorption and glucose metabolism in mice 全文
2019
Rezg, Raja | Abot, Anne | Mornagui, Bessem | Knauf, Claude
Bisphenol S, an industrial chemical, has raised concerns for both human and ecosystem health. Yet, health hazards posed by bisphenol S (BPS) exposure remain poorly studied. Compared to all tissues, the intestine and the liver are among the most affected by environmental endocrine disruptors. The aim of this study was to investigate the molecular effect of BPS on gene expression implicated in the control of glucose metabolism in the intestine (apelin and its receptor APJ, SGLT1, GLUT2) and in the liver (glycogenolysis and/or gluconeogenesis key enzymes (glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK)) and pro-inflammatory cytokine expression (TNF-α and IL-1β)). BPS at 25, 50, and 100 μg/kg was administered to mice in water drink for 10 weeks. In the duodenum, BPS exposure reduces significantly mRNA expression of sodium glucose transporter 1 (SGLT1), glucose transporter 2 (GLUT2), apelin, and APJ mRNA. In the liver, BPS exposure increases the expression of G6Pase and PEPCK, but does not affect pro-inflammatory markers. These data suggest that alteration of apelinergic system and glucose transporters expression could contribute to a disruption of intestinal glucose absorption, and that BPS stimulates glycogenolysis and/or gluconeogenesis in the liver. Collectively, we reveal that BPS heightens the risk of metabolic syndrome.
显示更多 [+] 显示较少 [-]Simultaneous removal of nitrogen oxides and sulfur dioxide using ultrasonically atomized hydrogen peroxide 全文
2019
Wei, Jiaqi | Gu, Junjie | Guo, Junheng | Li, Wei | Wang, Chenglong | Zhang, Jinli
A new method was developed for denitrification and desulfurization using hydrogen peroxide with the aid of an ultrasonic nebulizer to obtain high removal efficiency of NOx and SO₂. Comparing with the atomizing nozzles having the aperture size of 0.01~0.02 mm, the droplets generated using the ultrasonic nebulizer show the smallest d₅₀ value of 7.2 μm, with 72% possessing the size less than 10 μm. Based on the numerical simulation of the vaporization rate of droplets, it is indicated that the droplets with the size of 7.2 μm can be vaporized totally at very short residence time (0.11 s) under 130 °C. Effects of influence factors including the reaction temperature, the initial H₂O₂ concentration, pH value, and the flue gas flow rate were studied on the removal efficiencies of NO and SO₂. Using the in-series double-oxidation subsystems with H₂O₂ concentration of 6 wt%, pH 5.0, and the reaction temperature of 130 °C, the removal efficiencies of SO₂ and NO are respectively 100% and 89.3% at the short residence time of 1.8 s, and the removal efficiency of NO can be increased to 100% as the residence time is longer than 3.7 s. It is confirmed that the ultrasonically atomized H₂O₂ can indeed enhance the removal efficiencies of NO and SO₂ at the optimal temperature, owing to the fast vaporization rate of fine droplets as well as the formation of more active radicals to be captured by NO and SO₂ simultaneously. The results here provide a promising route to remove effectively the emissions of NO and SO₂ simultaneously. Graphical abstract
显示更多 [+] 显示较少 [-]The agro-enabled urban revolution, pesticides, politics, and popular culture: a case study of land use, birds, and insecticides in the USA 全文
2019
Brain, Richard A. | Anderson, Julie C.
Urbanization is an inevitable process in human civilization. When populations expand, socio-economic and political dynamics typically shift from agricultural predominance to one of industry and services. Accordingly, agrarian societies transform from diffuse rural communities to dense urban centers. By 2050, the world’s population is projected to reach 9.1 billion, with the urban population growing from 50 to 70%. Inevitably, this ever-expanding urban frontier encroaches along the human-ecological interface, creating a challenge for conservation and biodiversity. For the past 30 years, agricultural cropland area in the USA has remained fairly constant, despite significant population growth over the same time period. Thus, agricultural production in America has more than kept pace with rapid population growth and global export demand without increasing the farmland footprint at the expense of wildlife habitat. This is primarily due to considerable advances made in pesticide development, safety, and regulation, coupled with soil conservation and genetically modified crops. Still, the potential contribution of agriculture to ecosystem impairment remains contentious, particularly with regard to current use of pesticides. Recently, significant focus has been placed on the state of bird populations in the USA. Many species are considered imperiled, and this is often attributed in the popular media to pesticide use. However, focusing solely on the agricultural/chemical story as a significant driver of species viability and ecological risk within the broader biodiversity and conservation narrative lacks context and perspective. Moreover, the hypothesis that pesticides are indirectly affecting bird population status via reductions in food resources should be considered with caution and within the context of other likely causes. This work explores the dynamics between historical land use, human-controlled activity, and bird population trends from a holistic perspective within the USA. The aim is to provide context, developed from a relative comparison of potential contributing factors, in order to help inform discussion and foster dialogue between industry, academia, government, non-governmental organizations, and the public.
显示更多 [+] 显示较少 [-]Amorphous iron sulfide nanowires as an efficient adsorbent for toxic dye effluents remediation 全文
2019
Gadisa, Bekelcha Tesfaye | Appiah-Ntiamoah, Richard | Kim, Hern
Environmental and health concerns arising from the toxicity of organic dye effluents is still the issue of the twenty-first century. In that regard, this study presents iron sulfide (FeS₂) for its use in environmental remediation application. Amorphous phase FeS₂ nanowires were synthesized by PVP-assisted solvothermal reaction and were characterized using XRD, XPS, BET, FE-SEM, and EDS techniques. The amorphous phase FeS₂ is attractive from material synthesis point of view as its synthesis does not require delicate control over the process parameters, unlike the crystalline phase. The 1-D nanowire FeS₂ had a high surface-to-volume ratio with negative zeta potential within a wide pH range. Having those surface and microstructural properties, these nanowires exhibited excellent adsorption property towards model organic dyes, Congo red (anionic), and methylene blue (cationic), with theoretical adsorption capacity of 118.86 and 48.82 mg g⁻¹, respectively. Adsorption kinetics and isotherm models were implemented to study the adsorption processes at different adsorption conditions (pH, adsorbent loading, initial adsorbate concentration). The pH dependence of the adsorption and FT-IR analysis evidenced the prevalence of both physisorption and chemisorption during the adsorption of Congo red. Recyclability test proved the excellent performance of this amorphous FeS₂ nanowire adsorbent for three consecutive cycles. Considering its ease of synthesis, excellent adsorption property, and cyclic performance, the as-prepared adsorbent could be a promising material for dye effluents treatment.
显示更多 [+] 显示较少 [-]Determination of endogenous substance change in PM2.5-induced rat plasma and lung samples by UPLC-MS/MS method to identify potential markers for lung impairment 全文
2019
Fan, Ronghua | Ren, Qingquan | Zhou, Tao | Shang, Lei | Ma, Mingyue | Wang, Bolun | Xiao, Chunling
Exposure to fine particulate matter (PM₂.₅) could induce lung impairment aggravation. Moreover, endogenous substances are known to play a significant role in lung impairment. Therefore, the research objectives was to investigate the influence of PM₂.₅-induced lung impairment on the levels of the eight endogenous substances, γ-aminobutyric acid (GABA), acetylcholine (ACh), glutamate (Glu), serotonin (5-HT), 5-hydroxyindole-3-acetic acid (5-HIAA), noradrenaline (NE), dopamine (DA), and 3, 4-dihydroxyphenylacetic acid (DOPAC). A sensitive UPLC-MS/MS method for the simultaneous determination of these endogenous substances in rat plasma and lung tissues was developed. The validated method was successfully applied for comparing profiles of analytes in rat plasma and lung tissues. The results indicated that five endogenous substances, namely, GABA, Ach, Glu, DA, and DOPAC, had a significant change in the rats with PM₂.₅-induced lung impairment.
显示更多 [+] 显示较少 [-]Preparation of AgCl/TNTs nanocomposites for organic dyes and inorganic heavy metal removal 全文
2019
Tsai, Cheng-Yen | Liu, Chen-Wuing | Hsi, Hsing-Cheng | Lin, Kuen-Song | Lin, Yi-Wen | Lai, Li-Chi | Weng, Tsung-Nan
In this study, TiO₂ nanotubes (TNTs) and AgCl-modified TNTs nanocomposites with multiple crystal phases were synthesized through a hydrothermal method without calcination. The resultant samples had a large Brunauer-Emmett-Teller surface area. Additionally, the Ag modification process reduced the recombination rate of electron-hole pairs in the synthesized sample and possessed more oxygen vacancy sites. The surface area of the AgCl-modified TNTs was smaller than that of non-modified TNTs sample; however, the nanocomposites exhibited outstanding photocatalytic performance and adsorption properties. AgCl compounds present on the TNTs surface effectively interacted with Hg⁰, improving the dye photodegradation efficiency. The Hg⁰ removal efficiencies of the TNTs and AgCl-modified TNTs samples were about 63% and 86%, respectively. The crystal violet (CV) and malachite green (MG) removal efficiencies of the AgCl-modified TNTs sample were around 57% and 72%, respectively. Both dyes photodecomposition efficiencies for AgCl-modified TNTs sample are higher than those of TNTs sample. The oxygen vacancy on the AgCl-modified TNTs surface was determined to be advantageous for OH⁻ and arsenate adsorption through ligand exchange. The maximum adsorption quantity of As⁵⁺ calculated by Langmuir equation was 15.38 mg g⁻¹ (TNTs) and 21.10 mg g⁻¹ (AgCl-modified TNTs).
显示更多 [+] 显示较少 [-]Hybrid UV-C/microfiltration process in membrane photoreactor for wastewater disinfection 全文
2019
Rodríguez-Chueca, Jorge | Mesones, Sandra | Marugán, Javier
A novel hybrid UV-C/microfiltration process for water disinfection is presented, and its application in continuous mode operation to the removal of different pathogen germs (Escherichia coli, Enterococcus faecalis, and Candida albicans) present in urban wastewater. The membrane photoreactor is based on porous stainless steel membranes coated with a TiO₂ layer and illuminated by a UV-C lamp (254 nm). A valve actuator in the outlet of the UV-C stream allows operation of the system under conditions of constant transmembrane pressure (TMP) keeping the UV-C contact time in few seconds, significantly lower than the typical irradiation time employed in TiO₂ photocatalytic processes. An E. coli removal of up to 4-log in the permeate stream and up to 2-log in the UV-C outlet was achieved with a 0.2 μm membrane operating with a TMP of 0.5 bar and a UV-C contact time as low as 8 s. The microbial balance data from the cells recovered from the membrane confirmed that 96–98% of the removed microorganisms died due to the UV-C action over the membrane surface. Modification of the membrane with a TiO₂ layer has been also shown to be a suitable way to improve both the UV-C inactivation and the filtration efficiency. The results reported in this work constitute a proof of concept of the synergy between UV-C and filtration that can be achieved in a hybrid UV-C/microfiltration system, being a good example of process intensification where two products of different quality can be simultaneously obtained.
显示更多 [+] 显示较少 [-]Recycling of the scrap LCD panels by converting into the InBO3 nanostructure product 全文
2019
Assefi, Mohammad | Maroufi, Samane | Sahajwalla, Veena
Preparation of the value-added products from e-waste resources is an important step in the recycling process. The present paper aims to propose a methodology for the recovery of In from scrap LCD panel via preparation of InBO₃ nanostructure. Discarded LCD panel was subjected to a recycling process through crushing, milling, and oxalic acid leaching to prepare In₂(C₂O₄)₃·6H₂O. Through the leaching process, B(OH)₃ from glass part (alumina borosilicate) has been leached out along with indium oxalate hydrated. Further thermal treatment on these extracted materials at 600 °C could result in the formation of InBO₃ nanostructures with an average particle size of 20 nm. A multistep mechanism based on thermodynamic calculations for the recycling of the InBO₃ form extracted precursors was proposed. Graphical abstract
显示更多 [+] 显示较少 [-]Assessing the solar PV power project site selection in Pakistan: based on AHP-fuzzy VIKOR approach 全文
2019
Solangi, Yasir Ahmed | Shah, Syed Ahsan Ali | Zameer, Hashim | Ikram, Muhammad | Saracoglu, Burak Omer
Pakistan has an abundant solar power potential which can be effectively utilized for the electricity generation. There are various sites across the country which have sufficient solar irradiation across the year, and thus, suitable for the installation of solar photovoltaic (PV) power projects. This study, therefore, aims to undertake research on the establishment of solar power project site selection in Pakistan. In this context, 14 promising cities of Pakistan are considered as alternatives and studied in terms of economic, environmental, social, location, climate, and orography criteria and further supplemented with 20 sub-criteria. Initially, the analytical hierarchy process (AHP) method has been used to prioritize each of the main criteria and sub-criteria. Later, fuzzy VlseKriterijuska Optimizacija I Komoromisno Resenje (F-VIKOR) method has been employed to prioritize the 14 alternatives. The present investigation reveals that Khuzdar (C2), Badin (C3), and Mastung (C7) are the most suitable cities for the installation of solar PV power projects in Pakistan. Finally, the outcome of the sensitivity analysis revealed that obtained results are reliable and robust for the installation of solar PV power projects in Pakistan. This study shall assist government, energy planners, and policymakers in making cities sustainable by establishing solar power projects in Pakistan.
显示更多 [+] 显示较少 [-]Effects of Cr(VI) exposure on electrocardiogram, myocardial enzyme parameters, inflammatory factors, oxidative kinase, and ATPase of the heart in Chinese rural dogs 全文
2019
Lü, Jianwei | Liu, Kangping | Qi, Mengzhu | Geng, Hao | Hao, JiaJia | Wang, Run | Zhao, Xiaona | Liu, Yongxia | Liu, Jianzhu
Heavily chromium-polluted areas, where people are prohibited from entering, are paradises for stray dogs. In this study, stray dogs were used to study the effects of chromium exposure on the heart of dogs in severely Cr(VI)-contaminated rural areas of China. The dogs were given water (control), low dose (L, 0.92 mg/kg), medium dose (M, 1.15 mg/kg), and high dose (H, 1.38 mg/kg) of Cr(VI). The changes of electrocardiogram (ECG), myocardial enzyme parameters, inflammatory factors, oxidative kinase, and ATPase were measured to determine the toxicity of chromium on the heart of dogs. Results showed that the ST segment of ECG increased significantly, and the amplitude of T wave increased in the experimental group. The myocardial enzyme (CK-MB, AST, CK, and LDH) content in groups M and H increased significantly over time. The values of CAT, T-SOD, IL-10, and ATPase (K⁺-Na⁺-ATPase and Ca²⁺-Mg²⁺-ATPase) decreased with the increase of Cr(VI) dose, and the content of MDA, IL-1β, IL-8, and TNF-α increased with the increase of Cr(VI) dose. Our study suggested that the heart of Chinese rural dog was damaged by Cr(VI), and Cr(VI) could cause oxidative damage and alteration of ATPase content in dogs.
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