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Effects of Spartina alterniflora invasion on quality of the red-crowned crane (Grus japonensis) wintering habitat
2019
Wang, Juan | Liu, Hongyu | Li, Yufeng | Liu, Ling | Xie, Fufu | Lou, Cairong | Zhang, Huabing
The core zone of the Yancheng National Natural Reserve (YNNR) in China is the largest wintering habitat of red-crowned cranes (cranes) in the world. However, the invasion of Spartina alterniflora (S. alterniflora) not only changed the original landscape structure of the wetlands but also impacted the cranes’ habitats in the YNNR. In this paper, field investigation data and landscape pattern indices were used to analyze the effects of the S. alterniflora invasion on the habitat quality of wintering cranes. The results indicate that the seep weed (Suaeda salsa) in the natural wetland and the common reed (Phragmites australis) in the managed wetland both provide suitable habitats for cranes. However, the cranes prefer the natural wetland more. The explosive growth of S. alterniflora in the natural area has led to a significant reduction of the cranes’ habitat. The area of crane habitat decreased from 52.07 km² in 2000 to 22.36 km² in 2015. As a result of the S. alterniflora invasion, the benthic biomass has declined, which has negatively impacted the quantity and structure of the food utilized by the cranes. This study has both theoretical and practical significance and provides a scientific basis for protecting the wintering habitat of the red-crowned cranes.
显示更多 [+] 显示较少 [-]Assessing the solar PV power project site selection in Pakistan: based on AHP-fuzzy VIKOR approach
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 [-]Nongreen revolution: a case study of wild-grown edible mushroom
2019
Gurbuz, Ismail Bulent
Mushroom’s biological content has a positive effect on human welfare which is called “nongreen revolution”. It has an economic and social component that provides long-term food nutrition, environmental conservation, and regeneration of valuable resources. This article provides evidence that mushrooms can be a healthy food alternative to meat. In this study, analyzed data was collected from Marmara region of Turkey using a survey method. A survey questionnaire was prepared and distributed to a total sample size of 408 participants. Linear regression model y = α + β1×1+β2×2 was administered to determine the relationship of the variables. Secondary data were also used for the literature of the study. The study revealed that the consumption of mushroom accounts for 13.2% of the consumption of meat at the time of mushroom collection period. Consequently, it showed also that for every 1% increase in consumption of two species of mushrooms (Lactarius semisanguifluus and Macrolepiota procera var.) meat consumption decreases (−4.39, −2.97%).
显示更多 [+] 显示较少 [-]Sonophotocatalytic treatment of rhodamine B using visible-light-driven CeO2/Ag2CrO4 composite in a batch mode based on ribbon-like CeO2 nanofibers via electrospinning
2019
Sabzehmeidani, Mohammad Mehdi | Karimi, Hajir | Ghaedi, Mehrorang
CeO₂/Ag₂CrO₄ composite photocatalyst was successfully fabricated using electrospinning and calcination and chemical precipitation method based on CeO₂ ribbon-like fibers and characterized by field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS) and Fourier-transform infrared spectroscopy (FT-IR). The as-obtained CeO₂/Ag₂CrO₄ composite used photocatalytic performance in the sonophotodegradation of rhodamine B in aqueous solution under visible-light (LED) irradiation. DRS analysis illustrates that CeO₂/Ag₂CrO₄ composite exhibited enhanced absorption in the visible region-attributed CeO₂ nanofibers. The effect of four effective parameters including initial concentration of rhodamine B (RhB), photocatalyst dosage, pH, and irradiation time was studied and optimized using central composite design. The kinetic studies confirmed ability of pseudo first-order reaction based on the Langmuir–Hinshelwood model for fitting empirical data, while its rate constant (kₒbₛ), L–H rate constants (kᵣ), and L–H adsorption constants (KA) were 0.0449 min⁻¹, 11.66 mg L⁻¹ min⁻¹ and 1.09E−3 mg L⁻¹, respectively. The enhanced photocatalytic activity could be ascribed to the ultrasound field and formation of a heterojunction system among CeO₂ and Ag₂CrO₄, which lead to a better mass transfer and higher efficiency of charge electron–hole separation, respectively.
显示更多 [+] 显示较少 [-]Evaluation of the environmental noise problems in holiday villages: a case study from Antalya, Turkey
2019
Gürsoy, Özge | Yüğrük Akdağ, Neşe
Not only the appeal of the sun, natural, and historical beauties but also architectural features and business advantages of the accommodation facilities emerge as important factors in tourism development. Holiday villages differ from other types of accommodation facilities in terms of their functions and services. It is important to provide tourists acceptable levels of comfort in holiday villages offering various functions. One of these comfort conditions is acoustic comfort, which involves noise control. Noise emitted from various indoor and outdoor facilities is the main component impacting acoustic comfort in holiday villages. In this study, a holiday village in Antalya, Turkey with an open area of 120,000 m² was examined to identify noise exposure conditions of outdoor areas. Pools, restaurants, animation areas, playgrounds, and courts are the main outdoor noise sources in this holiday village. The noise emitted by these sources during daytime (Ld) and evening time (Le) are shown in noise maps. The open areas affected by 65 LAₑq noise level extend to an area of 55,500 and 21,000 m² during Ld and Le, respectively. With the noise barriers around the main noise sources, impacted open areas are reduced by 13% in Ld and 12% in Le. The results of this study clearly reveals the importance of resolving the issue of environmental noise in the most efficient and cost-effective way in terms of settlement and planning, especially in areas with dominant noise sources like holiday villages.
显示更多 [+] 显示较少 [-]Genotoxic, cytotoxic, and neurotoxic responses in Anodonta cygnea after complex metal mixture treatment
2019
Butrimavičienė, Laura | Stankevičiūtė, Milda | Kalcienė, Virginija | Jokšas, Kęstutis | Baršienė, Janina
Environmental effects associated with the release of various metals even at maximum permissible concentrations (MPC) to the aquatic ecosystems are evident. In the present work, time-dependent increase in accumulated metals amount in gills of Anodonta cygnea after exposure to complex metal (Zn 0.1, Cu 0.01, Ni 0.01, Cr 0.01, Pb 0.005, and Cd 0.005 mg/L, MPC accepted for the inland waters in EU) mixture at various time points (1, 2, 4, 7, 14, and 28 days) was investigated. Statistically significant increase of Cu and Cd was determined in mussel’s gills after 7-day exposure, in comparison to control group; moreover, significantly elevated concentration of Cu was measured and after 14-day treatment (in comparison to control and pre-exposure group). Concentrations of five (Cu, Ni, Cr, Pb, and Cd) out of 6 investigated metals were statistically increased in gills tissue after 28-day treatment. Moreover, complex metal mixture has demonstrated tissue- and time-dependent genotoxicity (∑Gentox) and cytotoxicity (∑Cytox) responses in mussels. After 4-day exposure, there were found the highest ∑Gentox levels in gills cells and haemocytes. Two-day treatment of mussels resulted in the highest and statistically significant induction of ∑Cytox level (in gills). Furthermore, after short-term (4 days) exposure, statistically significant inhibition of AChE activity in hemolymph of metal mixture–exposed mussels, in comparison to control and pre-exposure group, was found. Comparison of investigated responses in different tissue of A. cygnea discloses new information about metal mixture (at MPC) impacts at different treatment time. According to the obtained geno- and cytotoxicity data, it is suggested that gills are more sensitive tissue. Environmentally relevant trace metal concentrations when existing in mixture are able to cause adverse effects in A. cygnea; therefore, biological effects at different levels of organism are expected as a realistic scenario.
显示更多 [+] 显示较少 [-]Bisphenol S exposure affects gene expression related to intestinal glucose absorption and glucose metabolism in mice
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 [-]Neonicotinoid insecticide design: molecular docking, multiple chemometric approaches, and toxicity relationship with Cowpea aphids
2019
Bora, Alina | Suzukiski, | Funar-Timofei, Simona
Neonicotinoids are the fastest-growing class of insecticides successfully applied in plant protection, human and animal health care. The significant resistance increases led to the urgent need for alternative new neonicotinoids, with improved insecticidal activity. We performed molecular docking to describe a common binding mode of neonicotinoids into the nicotinic acetylcholine receptor, and to select the appropriate conformations to derive models. These were further used in a QSAR study employing both linear and nonlinear approaches to model the inhibitory activity against the Cowpea aphids. Linear modeling was performed by multiple linear regression and partial least squares and nonlinear modeling by artificial neural networks and support vector machine methods. The OECD principles were considered for QSAR models validation. Robust models with predictive power were found for neonicotinoid diverse structures. Based on our QSAR and docking outcomes, five new insecticides were predicted, according to the model applicability domain, the ligand efficiencies, and the binding mode. Therefore, the developed models can be confidently used for the prediction of the insecticidal activity of new chemicals, saving a substantial amount of time and money and, also, contributing to the chemical risk assessment.
显示更多 [+] 显示较少 [-]Large eddy simulation of turbulent flow structure in a rectangular embayment zone with different population densities of vegetation
2019
Xiang, Ke | Yang, Zhonghua | Huai, Wenxin | Ding, Ran
Dead-water zones (DWZs) in natural open channels, formed by embayment or consecutive groins, can provide favorable growth conditions for aquatic organisms. Although flow hydrodynamics in side-cavity zones have been well studied, the impact of vegetation on recirculating flow is rarely considered. This study adopts large eddy simulation (LES) to examine the flow field in a rectangular embayment zone with different population densities of vegetation. The numerical model is validated by mean streamwise velocity data collected near mid-depth in the physical experiment. Vegetation rearranges the circulation structure in the DWZ and weakens the velocity and turbulent kinetic energy. This negative effect increases with increasing population density. With the development of the shedding vortex induced in the front edge of the channel–embayment interface, the large-scale coherent structure forms in the mixing layer and is hardly affected by the variation of population density. As the population density increases, the mean retention time first decreases and then increases as a result of the combined action of three factors, namely, the large-scale coherent structure, the plant-induced Karman vortex street, and the blocking effect of dense vegetation.
显示更多 [+] 显示较少 [-]The effect of dimethoate pesticide on some biochemical biomarkers in Gammarus pulex
2019
Serdar, Osman
In this presented study, it was aimed to determine the effects of pesticides on non-target organisms on the freshwater amphipod, Gammarus pulex, by biochemical responses. Acute toxicity value (LC₅₀) in G. pulex of the dimethoate pesticide was determined. The superoxide dismutase (SOD), glutathione S-transferaz (GST), glutathione peroxidase (GPx), and catalase (CAT) activities and malondialdehyde (MDA), glutathione (GSH) levels of the G. pulex organism exposed to the subletal concentrations were analyzed by ELISA for 24 and 96 h. In conclusion, the present study demonstrated the abilities of dimethoate pesticide induce to oxidative stress. The results revealed that MDA, GSH levels SOD, CAT, GPx, and GST activities of G. pulex can be used as an effective biomarkers.
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