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Structural and Functional Determinants of Physiological Pliability in Kyllinga brevifolia Rottb. for Survival in Hyper-Saline Saltmarshes Texto completo
2021
Mumtaz, Sahar | Hameed, Mansoor | Ahmad, Farooq | Ahmad, M. S. A. (Muhammad Sajid Aqeel) | Ahmad, Iftikhar | Ashraf, Muhammad | Saleem, Muhammad Hamzah
The role of morpho-anatomical adaptations of six Kyllinga brevifolia populations in successfully invading hyper-saline environments was investigated. Physiological and anatomical characteristics showed a high degree of plasticity indicating its adaptability potential to a variety of environmental conditions. The population from hyper-saline saltmarsh Sahianwala was exposed to physiological drought for a long time and its survival relied on the prevention of water loss attained by decreased stomatal density and area, lignin deposition in the inner and outer cortical region, especially outside vascular tissue. Larger cells of cortical storage parenchyma aided in water storage and wide metaxylem vessels in better conduction of solutes. Higher accumulation of shoot Ca²⁺ in this habitat protected neutralized the impact of the enhanced shoot and root Na⁺ ion uptake. Organic osmoprotectants like total free amino acid, proline, soluble proteins, and sugars accumulated in a higher quantity that contributed towards an osmotic adjustment in Sahianwala population. Population from seasonal inundation (Treemu Headworks) showed larger root aerenchyma to supply sufficient oxygen for respiration, broader xylem vessels for better water and nutrient conduction, and greater density of leaf stomata for better transpiration. Maximum shoot and root length, total leaf area, and water potential were observed in the least saline Chinyot population indicating its best growth potential in a slightly saline aquatic environment. Each population showed specific physiological and anatomical modifications to colonize their respective habitats.
Mostrar más [+] Menos [-]The migration, transformation, and risk assessment of heavy metals in residue and bio-oil obtained by the liquefaction of pig manure Texto completo
2021
Luan, Hui | Liu, Fen | Long, Shundong | Liu, Zhuangzhuang | Qi, Yanting | Xiao, Zhihua | Fang, Jun
The total contents and chemical speciation analysis of Zn, Cu, Pb, Cr, Mn, Ni, Cd, and As in pig manure (PM), liquefaction residues (LRs), and bio-oils (BOs) derived from PM by liquefaction with ethanol as a solvent at 180–300 °C were thoroughly investigated in this study. The environment risk assessment, leachability, and bioavailability of heavy metals in PM and LRs were studied. The results showed that more than 75% of heavy metals remained in LRs. The total contents of heavy metals in LRs were markedly elevated, but those in BOs gradually decreased with the increase in liquefaction temperature. Moreover, the acid soluble/exchangeable fraction and reducible fraction (F1 + F2) of heavy metals in LRs and BOs was significantly reduced, while oxidizable fraction and stable fraction (F3 + F4) desirably increased after liquefaction. Furthermore, the potential risk of heavy metals in LRs was decreased in comparison to that in PM, but the risk of Pb, Mn, and As had not been obviously reduced; therefore, the LRs from the liquefaction of PM should be pretreated before recycling. Temperatures from 220 to 260 °C were the optimum conditions for disposing of PM by liquefaction with ethanol.
Mostrar más [+] Menos [-]Removal of nickel from neutral mine drainage using peat-calcite, compost, and wood ash in column reactors Texto completo
2021
Richard, Dominique | Neculita, Carmen Mihaela | Zagury, Gérald J.
The effectiveness of compost, peat-calcite, and wood ash to remove Ni from a circum-neutral-contaminated mine water was tested in continuous flow experiments. Materials were compared in 4.8-L columns at hydraulic residence times (HRT) of ∼ 16.5 h over the course of 2.5–4 months. During this period, all columns successfully treated over 400 L of synthetic contaminated neutral drainage (4.05 mg/L Ni), mainly through sorption processes. Mid-column results (HRT ∼ 9 h) indicated that wood ash was the most effective material for Ni removal, and chemical extractions revealed that retained Ni was less mobile in this spent material. The pH-increasing properties of wood ash played a major role in this material’s performance, but a pH correction would be required in the initial stages of full-scale treatment to maintain the effluent within regulatory limits (6–9.5). Scaled to full-sized, mid-column results indicated that treatment cell sizes, designed for the 1-year treatment of a high discharge (10 m³/h)–contaminated effluent (4.05 mg/L Ni), would be the smallest with wood ash (< 500 m³), followed by compost (600 ± 140 m³) and peat-calcite (720 ± 50 m³).
Mostrar más [+] Menos [-]In vivo exposure of marine mussels to venlafaxine: bioconcentration and metabolization Texto completo
2021
Gomez, Elena | Boillot, Clothilde | Martinez Bueno, Maria Jesus | Munaron, Dominique | Mathieu, Olivier | Courant, Frédérique | Fenet, Hélène
Pharmaceuticals are present in natural waters, thus contributing to the general exposure of aquatic organisms, but few data are available on the accumulation of these substances in marine organisms. The present study evaluated the in vivo bioconcentration of an antidepressant—venlafaxine (VLF)—in marine mussels (Mytilus galloprovincialis) during 7 days of exposure at nominal 10 μg/L concentration, followed by a 7-day depuration period. The bioconcentration factor (BCF) was 265 mL/g dry weight (dw). VLF accumulation reached an average tissue concentration of 2146 ± 156 ng/g dw within 7 days, showing a first-order kinetics process. N-desmethylvenlafaxine (N-VLF) and O-desmethylvenlafaxine (O-VLF) metabolites were quantified in mussel tissues, whereas N,N-didesmethylvenlafaxine (NN-VLF) was only recorded as being detected. These three metabolites were also quantified in water, indicating an active metabolism and VLF excretion in Mediterranean mussels. Complementary experiments conducted at nominal concentrations of 1, 10, and 100 μg/L for 7 days confirmed the VLF bioconcentration and metabolism and allowed us to quantify a supplementary metabolite, i.e., N,O-didesmethylvenlafaxine (NO-VLF), in mussel tissues. These results encourage further research on a more complete characterization of metabolism and on any disturbances linked to bioconcentration of VLF on bivalves.
Mostrar más [+] Menos [-]Adiantum capillus-veneris Linn protects female reproductive system against carbendazim toxicity in rats: immunohistochemical, histopathological, and pathophysiological studies Texto completo
2021
Madboli, Abd El-Nasser A. | Seif, Mohamed M.
This experimental study is done to clarify the protective role of the Adiantum capillus-veneris linn plant extracts (ACVL) in Sprague-Dawley female rat reproductive organs that are intoxicated by carbendazim pesticide (CBZ). This aim is achieved by the immunohistochemical detection of the inflammatory marker NF-ҡB-P65. This aim is achieved by the immunohistochemical detection of the inflammatory marker NF-ҡB-P65 and also, description of the histopathological and pathophysiological changes. Thirty-two rats were divided into four groups (n = 8) and were daily treated orally for 4 weeks. The first group as a control, the second group was treated with ACVL plant extract 200 mg/kg b.w., the third group was treated with CBZ 25 mg/kg b.w., and the fourth group was treated with CBZ 25 mg + ACVL plant extract 200 mg/kg b.w. The pathophysiological results showed that in the third group, the ovarian tissue malondialdehyde content was elevated, but the fourth group exhibited it at a normal level. Reductions in the ovarian tissue content of glutathione, superoxide dismutase activity, 3β-hydroxysteroid dehydrogenase, 17β-hydroxysteroid dehydrogenase, and also serum FSH, LH, and estradiol hormones were observed in the third group, while, in the fourth group, all these items recorded normal level. The histopathological findings in the third group exhibited severe congestion and hemorrhage in the ovaries, oviducts, myometrium, gastric submucosa, splenic white pulps, and brain subarachnoid spaces. The fourth group showed protection from the congestion and hemorrhage, and no histopathological changes occurred. The immunohistochemical results in the third group revealed strong positive immunoreaction against the NF-ҡB-P65 antigen in the uterus and stomach. Ovaries, spleen, and brain showed moderate positive immunoreaction. The fourth group disclosed negative immunoreaction for the NF-ҡB-P65 antigen. In conclusion, CBZ toxicity induced histopathological changes in female rat reproductive organs. CBZ induced changes in the enzymatic activities measured in ovarian and brain tissue homogenates. CBZ causes an elevation in NF-ҡB P65 as an inflammatory marker, especially in the uterus and stomach. The ACVL plant extract acts as a protective factor to prevent the CBZ toxicity and also has an anti-inflammatory effect by decreasing the synthesis of NF-ҡB-P65.
Mostrar más [+] Menos [-]Characteristics of colloids and their affinity for heavy metals in road runoff with different traffic in Beijing, China Texto completo
2021
Du, Xiaoli | Liang, Hui | Fang, Xing | Cui, Shenshen | Li, Junqi
The characteristics of colloids in urban road runoff with different traffic in Beijing, China, such as concentration, particle size, chemical property, and affinity for heavy metals were determined. The concentration of colloids was high, and an evident first flush effect was found in the runoff of road with heavy traffic. A large portion of colloids were distributed in the range of 1–10 μm. Traffic activity, rainfall intensity, and time of sample collection would not change the size distribution of colloids in the road runoff. The chemical property of colloids in the road runoff would be influenced by the soil erosion nearby green space, causing the content of organic colloids was high. The correlation coefficient between the concentration of colloids in colloidal fractions and the concentration of heavy metals (Cu, Zn, Cd, Pb, Fe, and Mn) in the road runoff with different traffic decreased with the same sequence from 0.02–0.2 μm, 0.2–0.45 μm, 0.45–1 μm, to 1–10 μm, suggesting that the heavy metals had stronger affinity for the colloids with small size. The concentration of Cu, Pb, and Zn exhibited significant correlations with the concentration of organic colloids in the road runoff. More aggregated spherical particles were found in the TEM image of the road runoff with heavy traffic. Zeta potentials and RMV data showed that the colloids with smaller size and the colloids in the road runoff with lighter traffic were much more stable.
Mostrar más [+] Menos [-]Protective effect of Beta vulgaris roots supplementation on anemic phenylhydrazine-intoxicated rats Texto completo
2021
Abd-El-Fattah, Mohy Eldin | Dessouki, Amina A. | Abdelnaeim, Noha S. | Emam, Bassant M.
Anemia is a public health problem that affects many people worldwide. Beetroot (Beta vulgaris) is a plant supposed to have many healthy features. The present study was done to evaluate the anti-anemic effect of beetroot supplement on anemia induced by phenylhydrazine in albino rats. Fifty rats were randomly divided into five equal groups. The control group was kept normal rats. In the second group, anemia was induced in rats by intraperitoneal injection of phenylhydrazine at 60 mg/kg in 3 divided doses daily, for 3 consecutive days. The last three groups received phenylhydrazine as the anemic group. Then, the third group received beetroot extract in dose 200 mg/kg for 24 days. The fourth group received beetroot powder in dose 1000 mg/kg for 24 days. The last group received iron (III) hydroxide polymaltose complex in dose 5mg/kg for 24 days. Our results showed that hemolytic anemia induced by phenylhydrazine in rats caused alteration in the blood picture, iron indices, serum biochemical parameters, antioxidant biomarkers, and histopathological picture. However, the supplementation with beetroot ameliorated these alterations, especially beetroot powder which showed powerful health effects compared to beetroot extract and iron preparation.
Mostrar más [+] Menos [-]Possible human health risk of some heavy metals from consumption of tilapia fish from Lake Mariut, Egypt Texto completo
2021
Shaaban, Nashwa A. | El-Rayis, Osman A. | Aboeleneen, Marwa S.
Lake Mariut Main Basin (MB) is not only one of the three basins composing Lake Mariut (LM) but is also the main source of the popular tilapia fish to Alexandrian people. Unfortunately, this basin was consistently for about 50 successive years receiving a continuous discharge of agricultural, sewage, and industrial effluents. This has led to contamination of the flesh of its tilapia fish living there particularly with some toxic heavy metals like Cd and Pb. Lately, in 2010, a rehabilitation program was adopted and carried out to save this vital MB from such intensive pollution. This had been achieved by diverting all those polluting sources. The present work is made after elapsing about 7 years from the diversion process date, to assess and evaluate the levels of those two metals (in addition to the other four one’s Fe, Cu, Cr, and Zn) in the edible flesh part besides the liver and gills of this fish (Nile tilapia spec., Oreochromis niloticus), and in ambient water of this restored basin to measure the efficiency of the rehabilitation program on quality of endogenous fish. A simultaneous parallel sampling program was also commenced for the other two basins of LM. The obtained results revealed that the concentration level of the studied metals in each of the muscles of the fish and the ambient water of the restored MB becomes now not only almost alike the metal levels of the corresponding compartments of the other two basins of LM, but also they became at concentration levels lay below those of their counterpart permissible limits in fish and water recommended by national and international standards. Health risk assessment indices: bioaccumulation factor (BAF), metal pollution index (MPI), estimated daily intake (EDI), hazardous index (HI), and relative risk (RR) for the present case were estimated, assessed, and subsequently evaluated. All are referring to a fact that MB is currently in good environmental condition and producing safe fish for human consumption.
Mostrar más [+] Menos [-]Treatment of the actual landfill leachate in different constructed wetlands through intermittent and varied aeration mode Texto completo
2021
Wang, Yi | Wang, Wen-Huai | Zhang, Heng | Yan, Fei-Long | Li, Jia-Jun
This study focused on the removal of organic matter and nitrogen and explored the feasible operation strategies to achieve short-cut nitrification and denitrification in two constructed wetlands (CWs), which were designed to treat the actual landfill leachate from a small county in parallel. The two CWs were horizontal sub-surface flow constructed wetlands (HFCW) with partial-area aeration and vertical sub-surface flow constructed wetlands (VFCW) with full-area aeration. The experimental results showed that both CWs could achieve an excellent organic matter and nitrogen removal performance under the conditions of intermittent aeration with high frequency and medium intensity (2 h of aeration and 4 h of rest). The removal efficiencies of COD and total nitrogen by HFCW were 89.08% and 73.22%, and the corresponding values of VFCW were 84.51% and 71.44%, respectively. Meanwhile, the inhibition kinetics model indicated that HFCW with partial-area aeration could enhance the free ammonium (FA) tolerance of ammonium-oxidizing bacteria (AOB) and reduce the conversion percentage of ammonia nitrogen. In addition, the intermittent aeration mode with high frequency and medium intensity could keep the DO concentration below under 0.60 mg L⁻¹ in HFCW, which helped to achieve stable short-cut nitrification and ensure the average nitrite accumulation rate (NAR) reach 50.96%. These results suggested that the intermittent aeration in partial-area could achieve successful short-cut nitrification in HFCW, thereby improving the removal efficiency of nitrogen in landfill leachate.
Mostrar más [+] Menos [-]Autotrophic nitrogen removal for decentralized treatment of ammonia-rich industrial textile wastewater: process assessment, stabilization and modelling Texto completo
2021
Visigalli, Simone | Turolla, Andrea | Bellandi, Giacomo | Bellucci, Micol | Clagnan, E. (Elisa) | Brusetti, Lorenzo | Jia, Mingsheng | Di Cosmo, Roberto | Menin, Glauco | Bargna, Martina | Bergna, Giovanni | Canziani, Roberto
Digital textile printing (DTP) is a game-changer technology that is rapidly expanding worldwide. On the other hand, process wastewater is rich in ammoniacal and organic nitrogen, resulting in relevant issues for discharge into sewer system and treatment in centralized plants. The present research is focused on the assessment of the partial nitritation/anammox process in a single-stage granular sequencing batch reactor for on-site decentralized treatment. The technical feasibility of the process was assessed by treating wastewater from five DTP industries in a laboratory-scale reactor, in one case investigating long-term process stabilization. While experimental results indicated nitrogen removal efficiencies up to about 70%, complying with regulations on discharge in sewer system, these data were used as input for process modelling, whose successful parameter calibration was carried out. The model was applied to the simulation of two scenarios: (i) the current situation of a DTP company, in which wastewater is discharged into the sewer system and treated in a centralized plant, (ii) the modified situation in which on-site decentralized treatment for DTP wastewater is implemented. The second scenario resulted in significant improvements, including reduced energy consumption (− 15%), reduced greenhouse gases emission, elimination of external carbon source for completing denitrification at centralized WWTP and reduced sludge production (− 25%).
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