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Effect of supra-nutritional selenium-enriched probiotics on hematobiochemical, hormonal, and Doppler hemodynamic changes in male goats Texto completo
2020
Mandour, Ahmed S. | Samir, Haney | El-Beltagy, Marwa A. | Abdel-Daim, Mohamed M. | Izumi, Watanabe | Ma, Danfu | Matsuura, Katsuhiro | Tanaka, Ryou | Watanabe, Gen
In this study, the influence of supra-nutritional organic selenium (Se) supplement on hematology and plasma biochemicals, including antioxidant parameters and plasma reproductive hormones, as well as blood flow characteristics in the supratesticular and common carotid arteries (STA and CCA, respectively) were investigated. For this purpose, 15 male goats were used and classified into three equal groups according to the supplementation of the basal diet (BD): negative control (NC), probiotic (Pro), and Se-probiotic (Se-Pro) groups. Blood perfusion in the STA and CCA was assessed by Doppler ultrasonography at three different time intervals: at the experimental onset (T0), 3 weeks of dietary supplement (T3), and after 6 weeks of observation (T6). Concomitantly, blood samples were withdrawn for hematobiochemical and hormonal changes. Results revealed no evidence of clinical abnormality, with some enhanced hematological parameters and antioxidant (SOD and GPX) levels in goats of the Se-Pro and Pro groups. High concentrations of FSH were found in the Se-Pro at T6 compared to its values in other groups. Similarly, testosterone levels were elevated in the Pro and Se-Pro groups at T3 compared to other time points. There were significant increases in levels of IGF-1 in the Pro and Se-Pro groups compared to the NC group. Significant (P < 0.05) increases in the values of the blood volume within the CCA and the STA were noted in the Se-Pro group, and the highest values were observed at T6 (CCA, 427.4 ± 33 ml/min; STA, 49.9 ± 5.0 ml/min). In conclusion, supra-nutritional organic selenium improves some hematobiochemical parameters, reproductive hormones, and the blood perfusion within the CCA and STA in goats.
Mostrar más [+] Menos [-]Impacts of anthropogenic activities and calculation of the relative risk of violating surface water quality standards established by environmental legislation: a case study from the Piracicaba and Paraopeba river basins, Brazil Texto completo
2020
Soares, Ana Luiza Cunha | Pinto, Carolina Cristiane | Oliveira, Sílvia Corrêa
The nonparametric test of Kruskal–Wallis and relative risk were used to evaluate surface water quality allowed to an identification of the most degraded water bodies in Piracicaba River and Paraopeba River basins, two important hydrographic basins in Brazil. Total manganese, dissolved iron, and fecal contamination indicator were considered the most relevant parameters for the characterization of water quality in the basins. The Peixe River, in Nova Era, and Pedras Creek, in Betim, were considered the most impacted water bodies in the Piracicaba River and Paraopeba River basins, respectively. The analysis of violations and the relative risk confirmed that both basins are subject to impacts resulting from economic activities. On comparing the relative risks, the Paraopeba River basin showed a higher risk of violation for 5-day biological oxygen demand (BOD₅), total manganese, total phosphorus, total suspended solids, and turbidity, while the Piracicaba River basin showed a higher risk of violation for fecal contamination indicator. The release of domestic sewage and industrial effluents, mining activities, and diffuse pollution from agriculture and pasture areas were responsible for the surface water quality deterioration in these basins. The results show the need for investment in basic sanitation, improved treatment efficiency for industrial effluents, adequate soil management, riparian vegetation preservation, and environmental education actions.
Mostrar más [+] Menos [-]Responses of nitrogen transformation and dissolved oxygen in constructed wetland to biochar and earthworm amendment Texto completo
2020
Zhou, Lei | Wang, Jiajun | Xu, Defu | Li, Yingxue | Yao, Bin | Howard, Alan
Many constructed wetland systems are facing the problem of low dissolved oxygen (DO) and reduced nitrogen removal efficiency. In this study, an experimental constructed wetland system is designed and used to investigate the effect of biochar (rice husk biochar (RHB), coconut shell biochar (CSB), and wood biochar (WB) and earthworm on DO concentration, nitrogen transformation, and ammonia nitrogen removal. Specifically, effects of different biochar and earthworm on NH₄⁺-N in wastewater, N content of Phragmites australis, NH₄⁺-N and NO₃⁻-N content in substrates, microbial nitrification and denitrification potentials, and the DO concentration were investigated. Results show that the addition of biochar and earthworm increased the removal efficiency of NH₄⁺-N from wastewater. The addition of RHB and WB significantly increased the concentration of DO by 21.4% and 25.7% (P < 0.05) respectively in the constructed wetland. The addition of earthworm significantly increased the DO concentration in the constructed wetland system by an average of 30.35% (P < 0.05).The N content of P. australis increased when biochar and earthworm were introduced into the constructed wetland system, with higher relative N content observed in the above-ground biomass. NO₃⁻-N content increased, but NH₄⁺-N decreased in the substrate. Addition of both biochar and earthworm increased nitrification and denitrification potentials. However, no significant increase in denitrification potential was observed when only biochar was added. The removal efficiency of NH₄⁺-N from wastewater is significantly positively correlated with the DO, nitrification, and denitrification potential, and nitrogen content of above-ground part of P. australis (P < 0.05). Results suggest that the DO concentration in constructed wetland systems could be improved by the addition of biochar and earthworm. These findings imply that both biochar and earthworm could be added into constructed wetlands to solve the low DO concentration and improve the removal efficiency of nitrogen.
Mostrar más [+] Menos [-]Population structure of Nile tilapia and its impact on fisheries of a tropical impacted reservoir, Central India Texto completo
2020
Johnson, Canciyal | Sarkar, Uttam Kumar | Koushlesh, Sathis Kumar | Das, Archan Kanti | Das, Basantakumar | Naskar, Bablu Kumar
Length-frequency data of Nile tilapia (Oreochromis niloticus) was studied using 1250 specimens of both sexes combined with maximum length and weight of 44.5 cm (TL) and 1050 g respectively through gill net catch at different landing sites of Halali Reservoir, Madhya Pradesh. The data were grouped into classes of 10-mm intervals and various parameters of population dynamics of fish were analysed and computed using the FiSAT-II software package (FAO-ICLARM Stock Assessment Tools). The length-weight parameters were found to be at W = 0.001 L ².⁹⁶ where b = 2.96 and a = 0.001. Growth parameters L∞ and K of the species were L∞ = 46.73 cm and K = 0.63/year respectively; the annual rates of natural (M) and fishing mortality (F) were found to be 0.60 and 0.72 respectively. The estimated values for the exploitation rate (E) using the length-converted catch curve and virtual population analysis were 0.54 and 0.42 respectively. The recruitment pattern shows that O. niloticus was recruited in the fishery during April with one peak. Based on the data analysis, the stock in the Halali Reservoir does not exceed the maximum fishing pressure (Emax = 0.55) and there is selective mortality towards adult fish sizes. The introduction of Nile tilapia improved the total catch per unit of effort (CPUE), as well as increased the number of active fishers. Conversely, a significant reduction in the CPUE of other commercially important indigenous species was observed after the introduction of Nile tilapia in the reservoir. Therefore, for management purpose, this study suggests that the existing effort in terms of gill net mesh size which target size (TL—15.0 to 25.0 cm) individuals of length group is to be increased to exert more fishing pressure on Nile tilapia population in the reservoir to decline its abundance in the long term.
Mostrar más [+] Menos [-]Enhanced removal of phosphate and ammonium by MgO-biochar composites with NH3·H2O hydrolysis pretreatment Texto completo
2020
Xiao, Ran | Zhang, Han | Tu, Zhineng | Li, Ronghua | Li, Songling | Xu, Zhongyang | Zhang, Zengqiang
In this study, a novel MgO-biochar composite was generated for nutrient recovery from biogas slurry using magnesium chloride (MgCl₂) and ammonia hydroxide (NH₃·H₂O). Biochar properties, including pH, CEC, pHpzc, magnesium content, surface area, and total pore volume (Vₜₒₜₐₗ), were evaluated. Moreover, the removal of NH₄⁺ and PO₄³⁻ in both single and bi-solute system were investigated. Results indicated that NH₃·H₂O pretreatment and MgO-coating enhanced biochar pH, CEC, and pHpzc. Additionally, there were generally higher surface area and Vₜₒₜₐₗ in MgAWS₅₅₀. The maximum adsorption capacities for NH₄⁺ and PO₄³⁻, respectively, increased as WS₅₅₀ (0.555 and 1.57 mg g⁻¹) < MgWS₅₅₀ (15.4 and 21.8 mg g⁻¹) < MgAWS₅₅₀ (17.5 and 31.3 mg g⁻¹). Moreover, higher removal efficiencies were achieved in the bi-solute system, and over 25% and 90% of NH₄⁺ and PO₄³⁻, respectively, was removed from biogas slurry by MgASW₅₅₀. Mechanically, NH₄⁺ removal was mainly attributed to ionic exchange, while PO₄³⁻ adsorption on MgO-coated biochars was due to electrostatic attraction and precipitation. Furthermore, the formation of struvite (MgNH₄PO₄·6H₂O) further enhanced N and P in the bi-solute system.
Mostrar más [+] Menos [-]Health risk assessment of heavy metals in cosmetic products sold in Iran: the Monte Carlo simulation Texto completo
2020
Ghaderpoori, Mansour | Kamarehie, Bahram | Jafari, Ali | Alinejad, Abdol Azim | Hashempour, Yalda | Saghi, Mohammad Hossein | Yousefi, Mahmood | Oliveri Conti, Gea | Mohammadi, Ali Akbar | Ghaderpoury, Afshin | Ferrante, Margherita
Cosmetics can contain harmful compounds such as heavy metals. Several metals have a cumulative effect on the body, especially fatty tissues, and may have different health effects on the human body over the long term. Therefore, the main objective of this study was to assess the health risks of heavy metals in cosmetics in Iran. Also, in this study, Monte Carlo simulation was used to investigate uncertainties. In this study, heavy metals data of cosmetics were extracted from studies carried out at intervals 2010–2018. International and Iranian databases such as Google Scholar, Web of Science, Springer, Science Direct, PubMed, Scopus, Irandoc, Magiran, Scientific Information Database (SID), and Information Institute for Scientific (ISC) were searched for this purpose. In this study, the index of the Margin of Safety was calculated to determine the risk of human contact with metallic impurities in cosmetic products used by humans. In the selected period, 11 studies were conducted on the measurement of heavy metals in cosmetics in Iran. In these studies, cosmetics such as eye shadow, eye pencil, powder, cream, and lipstick were studied. The Margin of Safety (MoS) values calculated for different metals were higher than the established safe standard by WHO. The highest and lowest amount of systemic exposure dosage in all types of cosmetic investigated (lipstick, cream, eye pencil, face powder, and eye shadow) was related to Fe and Hg. The mean hazardous quotient (HQ) for Cd, Cr, Ni, Cu, Mn, Zn, Pb, and Hg was 1.05E-03, 1.03E-01, 7.95E-03, 2.59E-03, 1.05E-03, 4.98E-03, 7.22E-04, 1.85E-01, and 1.35E-05, respectively. The highest HQ (6.10E-01) was found for Pb, which was observed in the cream.
Mostrar más [+] Menos [-]Cadmium immobilization in aqueous solution by Aspergillus niger and geological fluorapatite Texto completo
2020
Okolie, Christopher Uche | Chen, Haoming | Zhao, Yexin | Tian, Da | Zhang, Lin | Su, Mu | Jiang, Zhonquan | Li, Zhen | Li, Huixin
This study investigated the application of fungus Aspergillus niger and geological fluorapatite (FAp) to cadmium (Cd) immobilization in aqueous solution. The initial Cd concentrations were set at 100, 50, 25, and 10 mg L⁻¹. The mineralogy of the products was investigated by using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and attenuated total reflection–infrared spectroscopy (ATR-IR). In both A. niger + FAp + Cd and A. niger + Cd treatments, A. niger secreted abundant oxalic acid, then dissolved the FAp, and reacted with Cd²⁺ cations to produce relatively insoluble Cd oxalate. Meanwhile, FAp can provide P source to improve microbial growth. The fungal tolerance to Cd²⁺ was identified at around 100 mg L⁻¹. The final Cd concentrations of 13.7, 3.2, and 0.2 mg L⁻¹ were recorded for A. niger + FAp + Cd treatments with initial Cd concentrations of 50, 25, and 10 mg L⁻¹ respectively. Meanwhile, it was observed that the Cd concentration at 25 mg L⁻¹ stimulated higher bioactivities of A. niger, which further enhanced Cd bioremediation. The immobilization efficiency (%) of the treatments at low to medium Cd concentrations was in the order: Asp + FAp > Asp > FAp, while FAp alone was most efficient at the high Cd concentration of 100 mg L⁻¹. This research provides insights into the mechanisms of combining fungus and FAp as a composite to Cd contamination at various Cd levels.
Mostrar más [+] Menos [-]Arsenate removal from underground water by polystyrene-confined hydrated ferric oxide (HFO) nanoparticles:effect of humic acid Texto completo
2020
Deng, Yirong | Zhang, Qingjian | Zhang, Qingrui | Zhong, Yin | Peng, Ping’an
Arsenic decontamination from groundwater is an urgent but still challenging task. Polystyrene-based hydrated ferric oxide (denoted as D201-HFO) nanocomposite is a new emerging current adsorbent for efficient arsenate removal in natural waters; the resulting materials can interact with arsenate, mainly driven by inner complexation and static interaction and the existing HA effects on adsorption was well investigated. Results reveals that low concentrations of HA (below 25 mg/L) coexistence led to negligible effects on As(V) removal, but high levels of HA (100 mg/L) exerted outstanding sorption competition to As(V) removal; kinetics results revealed the HA additions brought about the diffusion prolonging and capacity decline, due to the large molecule structure of HA. Column experiments further showed the slight decrease application capacity of 810 BV by HA additions, with satisfactory saturation capacity; significantly, the presence of HA also exerted negligible influences on regeneration performances. All the sorbents with or without HA could be well regenerated by binary alkaline and salt mixture.
Mostrar más [+] Menos [-]Influence of green waste compost on Pb-polluted soil remediation, soil quality improvement, and uptake by Pakchoi cabbage (Brassica campestris L. ssp) Texto completo
2020
Liu, Yuanxin | Sun, Xiangyang | Li, Song | Li, Suyan | Zhou, Wenjie | Ma, Qixue | Zhang, Jiali
Green waste compost (GWC) has been widely used as organic mulches, growing media, soil organic fertilizer, and amendment in Beijing, China. The aim of this study is to determine the remediation efficiency of GWC on the Pb concentration in soil and uptake by pakchoi cabbage and to assess the activities of dehydrogenase, urease, and catalase after applying GWC. Original soil samples were spiked with Pb (NO₃)₂ of 500 mg/kg, and greenhouse pot experiment was carried out. Three seedlings of pakchoi cabbage (Brassica campestris L. ssp) were planted in plastic pots with mixture of soil amended with three levels of GWC (2%, 5%, and 10%, w/w). Soil and plant samples were collected over 45-day growth, after which Pb concentration and enzyme activities were assessed by laboratory analysis. The available Pb in soil and total Pb in roots and leaves of pakchoi cabbage greatly decreased after adding GWC, associated with significant increases in organic matter, water soluble organic carbon, total nitrogen, and available K and P, whereas pH was not a main factor controlling Pb speciation in this study. Activities of dehydrogenase, urease, and catalase were promoted with addition of GWC because physical properties, high organic matter, and organic carbon content rose by 9-fold, 40%, and 37% at 10% application rate, respectively. In conclusion, GWC could be an alternative option for the remediation of Pb-contaminated soil because of soil quality improvement and Pb reduction in soils and plants, without introducing extra heavy metals compared with other organic amendments.
Mostrar más [+] Menos [-]Effect of carbon nanotubes loading on the photocatalytic activity of BiSI/BiOI as a novel photocatalyst Texto completo
2020
Bargozideh, Samin | Tasviri, Mahboubeh | Ghabraei, Mana
In this paper, a simple hydrothermal method is employed to synthesize BiSI/BiOI/CNT nanocomposite with enhanced photocatalytic activity. The properties of the prepared samples were studied using nitrogen adsorption-desorption isotherm, photoluminescence, X-ray diffraction analysis (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), UV–vis diffuse reflectance spectroscopy (DRS), and electrochemical impedance spectroscopy (EIS). The loading amount of CNT had a significant influence on the photoactivity of the BiSI/BiOI/CNT composite. In this study, several BiSI/BiOI/CNT nanocomposite samples with various mass ratios of CNT were made-up for further investigation to scrutinize the influence of CNT content on the photocatalytic activity of the nanocomposite. Photocatalysis measurements revealed that 2% Wt of CNT possesses the highest photocatalytic activity in the visible light irradiation with 93.1% photodegradation of malachite green (MG) as a test dye. The enhanced photocatalytic performance can be due to the large surface area, excellent conductivity performance, and high absorption ability in the visible light region. The synergistic effect of the factors mentioned above makes BiSI/BiOI/CNT nanocomposite a high-performance photocatalyst under visible light irradiation. An appropriate reaction mechanism of dye photodegradation has suggested according to the result of active species trapping experiments.
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