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1.
Chemosphere ; 251: 126442, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32169715

RESUMO

This study aimed to compare the effectiveness of MAER and L20 resin for the adsorption treatment of secondary effluent, and evaluate the applicability of ozone oxidation for the reuse of desorption eluate. Bench-scale adsorption experiments showed that the MAER resin exhibited higher efficiency than L20 resin in removal of COD within 600 treated bed volumes (BV), which declined from 32.5% to 14.1% in the first and sixth treatment loading of 100 BV. On the other hand, the L20 resin displayed obviously higher removal efficiency of total nitrogen (TN) than MAER resin within 600 BV, which dropped from 74.6% to 9.8% at the same condition. The ozone oxidation treatment could achieve desirable reuse of desorption eluate, although its chemical oxygen demand (COD) concentration increased gradually in line with the reuse numbers. The uptake of COD, TN and total phosphorus declined steadily by using ozone treated eluate as the regenerant in successive adsorption-desorption cycles, but increased obviously with a new batch of regenerant. Overall, the resin adsorption could efficiently remove organic and inorganic matters from secondary effluent, while the treatment loop including desorption eluate oxidation and eluate reuse could markedly enhance the concentration ratio of treated effluent.

2.
Soft Matter ; 16(12): 2928-2932, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32154538

RESUMO

A diversified and biocompatible rhythmic deformation (RD) system is successfully fabricated by coupling a heterogeneous hydrogel with a pH oscillator. By tailoring the geometry of the building blocks, a heterogeneous hydrogel actuator with diversity could be easily constructed through interfacial adhesion. Moreover, the RD behaviour can be regulated by the system temperature and actuator shape.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32174106

RESUMO

Phase change memory (PCM) is regarded as a promising technology for storage-class memory and neuromorphic computing, owing to the excellent performances in operation speed, data retention, endurance, and controllable crystallization dynamics, whereas the high power consumption of PCM remains to be a short-board characteristic that limits its extensive applications. Here, Sc-doped Bi0.5Sb1.5Te3 has been proposed for high-speed and low-power PCM applications. An operation speed of 6 ns and a threshold current of 0.7 mA have been achieved in 190 nm Sc0.23Bi0.5Sb1.5Te3 PCM, which consumes lower power than GeSbTe and ScSbTe PCM. A good endurance of 5 × 105 has been achieved, which is attributed to the small volume change of 4% during phase change and a good homogeneity phase in the crystalline state. The structure of amorphous Sc0.23Bi0.5Sb1.5Te3 has been characterized by experimental and theoretical methods, showing the existence of a large amount of crystal-like structural factions, which can efficiently minimize the atomic movements required for crystallization and subsequently improve the operation speed and power efficiency. The low diffusivity of Sc and Bi at room temperature and the rapidly increased diffusivity of Bi at elevated temperatures are fundamental for the high data retention of 94 °C and the fast crystallization in Sc0.23Bi0.5Sb1.5Te3. The combination of high atomic mobility and minimized atomic movements during crystallization ensures the high speed and low power consumption of Sc0.23Bi0.5Sb1.5Te3 PCM, which can promote its application to energy-efficient systems, that is, AI chips and wearable electronics.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32037493

RESUMO

Globally, odorant incidents are occurring at an increasing frequency, magnitude, and duration under the dual influences of eutrophication and climate change. However, the contribution of multiple ecotypes to odorant production in the complicated and dynamic lake ecosystems remains unclear. In this study, the odorants and environmental conditions in algae-dominated zones (ADZs) and macrophyte-dominated zones (MDZs) in Lake Taihu were identified and characterized. Results showed that the ADZs were characterized by an abundance of pigments and nutrients and low DO levels, while the MDZs were featured as high TOC/TN ratios and high DO levels. Most odorants in ADZs and several in MDZs exceeded the odorant threshold content. The dominant odorants were dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS), ß-ionone and ß-cyclocitral in ADZs, which were associated with the accumulation and decomposition of algal detritus. For MDZs, the dominant odorants were 2-methylisoborneol (2-MIB) and geosmin, which were at least partially attributed to the massive addition of bait in a traditional aquaculture area. In addition, the odorant concentration in the water of ADZs was approximately 3 to 21 times higher than that in MDZs, while in the benthic sediment, the odorant concentration in ADZs was approximately 2 to 3 orders of magnitude higher than in MDZs. This study highlights the production and accumulation of nuisance odorants in the benthic sediment of ADZs, indicating a risk of diffusion from the sediment to the water column. This was supported by the correlation of odorants in the water column with that in the sediment. The results of this study will be helpful for the management of different ecotypes suffering from nuisance odorants problems.

5.
Environ Pollut ; 261: 114212, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32109823

RESUMO

Volatile fatty acids (VFAs) are a major component of dissolved organic matter in alkaline fermentation supernatants. In this study, effects of different VFAs (acetate, propionate, and butyrate) on phosphorus recovery, as magnesium ammonium phosphate (MgNH4PO4·6H2O, or MAP), were studied. Results showed that optimal pH was 9.5 and MAP purity was ∼70% in VFA-free wastewater. With VFA addition, MAP purities of precipitates were higher, reaching 75%-85%. The crystalline characterization of precipitates suggested that VFAs had a weak complexation ability with Mg2+ and NH4+. Further, pH changes during the MAP crystallization process were monitored and results indicated VFAs only contributed to the alkalinity condition, which, in turn, improved the MAP crystallization process. These data provide for a better understanding of P recovery by MAP precipitates from VFA-rich fermented supernatants.

6.
Turk J Gastroenterol ; 31(1): 42-48, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32009613

RESUMO

BACKGROUND/AIMS: Studies evaluating submucosal tunneling endoscopic resection (STER) for the treatment of upper gastrointestinal submucosal tumors (SMTs) have recently increased. However, the efficacy and safety of STER for the treatment of large symptomatic SMTs in the esophagus have not been well investigated. The aim of the present study was to evaluate the efficacy and safety of STER for the treatment of large symptomatic SMTs in the esophagus. METHODS: A total of 24 patients with large symptomatic SMTs in the esophagus who underwent STER in our hospitals between January 2015 and May 2018 were included in the study. The tumors were confirmed to be of muscularis propria layer origin. Treatment outcomes, complications, and follow-up results were retrospectively analyzed. RESULTS: All 24 lesions were resected en bloc with STER. The mean maximum transverse diameter of the lesions was 4.7 (3.5-6.5) cm. The mean maximum longitudinal diameter of the lesions was 2.1 (1.5-3.0) cm. The mean duration from mucosal incision to complete mucosal closure was 65 (50-115) min. Postoperative pathological diagnosis confirmed 18 cases with leiomyomas, 4 cases with stromal tumors, and 2 cases with schwannomas. There were no major complications. There were no residual lesions or disease recurrence during follow-up. CONCLUSION: STER is safe and effective for the treatment of large symptomatic SMTs of muscularis propria layer origin in the esophagus.

7.
Environ Sci Pollut Res Int ; 27(2): 2319-2327, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31776910

RESUMO

Ammonia (NH3) volatilization from paddy soils is a main source of atmospheric NH3 and the magnitude is affected by many factors. Because of the complex field condition, it is difficult to identify the relative importance of individual factor on NH3 volatilization process in different locations and at different times. In this study, the grey relational entropy method was used to evaluate the relative impact of four main factors (i.e., nitrogen fertilizer application rate, NH4-N concentration, pH, and temperature of the floodwater) on NH3 volatilization loss from three different field experiments. The results demonstrated that floodwater NH4-N concentration was the most important factor governing NH3 volatilization process. Floodwater pH was the second most important factor, followed by temperature of the floodwater and nitrogen fertilizer application rate. We further validated the grey relational entropy method with NH3 volatilization loss data from other published study and confirmed the order of importance for the four factors. We hope the findings of this study will be helpful for guiding design to reduce paddy soil NH3 emission.

8.
Environ Pollut ; 256: 113453, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672349

RESUMO

Eutrophic freshwater lake ecosystems are receiving increasing public attention due to a global increase in large-scale harmful cyanobacterial blooms in surface waters. However, the contribution of phytodetritus accumulation in benthic sediments post-bloom remains unclear. In this study, field investigations were performed using microsensors to evaluate benthic phytodetritus mats by measuring TOC/TN ratios, pigments, biodegradable compounds and odorants as descriptive parameters. Results show that the massive amount of phytodetritus trapped by aquatic plants gradually evolved into benthic cyanobacterial detritus mats, which were characterized as anoxic, reductive and low pH. It was confirmed that the occurrence of odorants is more serious in the detritus mats due to decay and decomposition of the accumulated phytodetritus. The mean odorant content in the vegetated zones was 3-52 times higher than that in the unvegetated zones. The dominant odorants were dimethyl trisulfide (DMTS), ß-ionone and ß-cyclocitral, with mean contents of 52.38 ng·(g·dw)-1, 162.20 ng·(g·dw)-1 and 307.51 ng·(g·dw)-1, respectively, in the sediment. In addition, odorant production appears to be associated with the distribution of biodegradable compounds in the sediment. This is supported by the marked correlation observed between biodegradable compounds and odorants. Multiple regression analysis showed that biodegradable compounds can be used as indicators to predict odorant content in the sediment. It is noteworthy that the odorant trend in the water column and sediment is symmetrical, indicating a risk of diffusion from the sediment to the water column. This study helps to clarifying the contributions of benthic cyanobacterial detritus mats to odorant production in shallow eutrophic lakes. The information provided herein may also be useful for future management of aquatic ecosystems.


Assuntos
Cianobactérias/fisiologia , Monitoramento Ambiental , Odorantes , Ecossistema , Eutrofização , Sedimentos Geológicos/microbiologia , Lagos/química , Sulfetos
9.
Sci Total Environ ; 698: 134328, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783469

RESUMO

In eutrophic lacustrine ecosystems, drifting algal blooms are easily trapped by emergent macrophytes in downwind littoral zones, potentially altering carbon cycling processes; yet, knowledge remains limited about the mechanisms driving these changes. In this study, Microcystis and Phragmites, two dominant photosynthetic organisms in a hypereutrophic (Lake Taihu, China), were collected to simulate their co-decomposition processes. We demonstrate how molecular-level biomarkers could be used to elucidate the degradation dynamics of these two distinct organic forms in mixtures. Microcystis-derived carbon accelerated the decomposition rate of mixed systems (positive co-metabolism effect), rather than retarding it. The decomposition rate of TOC (total organic carbon) directly measured in the mixed treatments was 14% higher than when the two substrates were incubated alone. The use of specific fatty acid biomarkers facilitated more accurate tracking, demonstrating 1.09 times higher decomposition rates for Phragmites detritus in mixed treatments than in single Phragmites treatments. Furthermore, Microcystis showed 0.98 times higher decomposition rates in mixed treatments than in single treatments. The addition of Microcystis detritus to Phragmites detritus might meet microbial stoichiometric requirements, increasing the abundance of decomposing bacteria in Phragmites detritus, and accelerating decomposition rates, resulting in the co-metabolism of Microcystis and Phragmites carbon. Given the increasing occurrence of algal blooms in eutrophic lakes, the processes documented here might enhance greenhouse gas emissions from lakes with continued global climate warming.


Assuntos
Monitoramento Ambiental , Lagos/química , Poluentes da Água/análise , Biomarcadores , China , Ecossistema , Eutrofização , Sedimentos Geológicos , Microcystis
10.
Aquat Toxicol ; 219: 105374, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862549

RESUMO

Phytoremediation is an effective and environmentally friendly approach to treat antibiotic contaminated water, however, the mechanisms of migration and transformation of antibiotics in plant tissues are still far from clear. In this study, the floating macrophyte Eichhornia crassipes was exposed to a series of antibiotic ciprofloxacin (CIP) concentrations. The results showed that the CIP was taken up and accumulated in the roots, which were the major accumulative tissue. CIP content increased with lipid content. During cultivation, the root bioconcentration factor (RCF) gradually increased. The average CIP content detected in aerial parts was 12.80 µg g-1, an order of magnitude lower than in the roots. At low CIP concentrations, the highest leaf bioconcentration factor (LCF) and transfer factor (TF) indicated highly efficient translocation from roots to aerial parts. The soluble protein growth rate of leaves, which is associated with metabolic activity, increased following CIP exposure. Overall, eight major transformation products in E. crassipes tissues were identified, and three possible transformation pathways were proposed involving the processes of desethylation, dehydroxylation, oxidation, hydroxylation and cleavage of the piperazine and quinoline rings. These findings could prove beneficial for improving the management or amelioration methods used for treating water contaminated with antibiotics.


Assuntos
Antibacterianos/análise , Bioacumulação , Ciprofloxacino/análise , Eichhornia/efeitos dos fármacos , Poluentes Químicos da Água/análise , Antibacterianos/metabolismo , Biodegradação Ambiental , Biotransformação , Ciprofloxacino/metabolismo , Eichhornia/metabolismo , Poluentes Químicos da Água/metabolismo
12.
Huan Jing Ke Xue ; 40(12): 5367-5374, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854608

RESUMO

To reveal the distribution characteristics of carbon, nitrogen and phosphorus in the sediments of Zhushan Bay at Taihu Lake, sedimentary columns were collected and sliced by 2 cm vertically from ten sampling points in three sections of Zhushan Bay. The content of total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) were determined for each slice to reveal their horizontal and vertical distribution. The results showed that:spatially, the content of TN, TP, and TOC increased in the surface sediments of Zhushan Bay from the open lake area to the bay, and inside the bay these indexes were significantly higher than in the open lake area (P<0.01). The content of TN, TP, and TOC in the surface sediments in the bay (section A) were 1.53 mg·g-1, 1.55 mg·g-1, and 11.31 mg·g-1, respectively, while in the surface sediments near the open lake (section C) they were only 0.75 mg·g-1, 0.57 mg·g-1, and 6.70 mg·g-1, respectively. Vertically, a feature of surficial enrichment was shown, and the contents of carbon, nitrogen and phosphorus in all three sections showed a decreasing trend with increase of depth. The contents of TN, TP and TOC in the surface sediments are 2-3 times, 2-5 times, and 2-3 times those in the bottom sediments, respectively. Generally, the average TP content in the sediment of Zhushan Bay is 0.93 mg·g-1, suggesting an apparent heavy pollution, while the average TN content is 1.11 mg·g-1 as slight pollution. According to the organic nitrogen index and comprehensive pollution index, the northern part of Zhushan Bay is suffering from heavy pollution, where the organic pollution is relatively strong. The TP pollution index is between 1.03 and 3.87, indicating heavy pollution in Zhushan Bay.

13.
Huan Jing Ke Xue ; 40(10): 4505-4512, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854818

RESUMO

In shallow eutrophic lakes, benthic bioclastic deposits accumulate abundant organic carbon derived from macrophyte detritus. Taking the typical macrophyte-dominated Xukou Bay as the study area, field investigations were performed using sediment cores to evaluate benthic phytodetritus accumulation. Specifically, nutrient contents, TOC/TN ratios, pigmentation, and biodegradable compounds were measured as descriptive parameters. The results show that the benthic bioclastic deposit had accumulated abundant pigments, nutrients, and biodegradable compounds derived from macrophytes detritus. These were mainly localized in the top 15 cm of sediments. Nitrogen loading in the sediments was significantly higher than phosphorous loading, with a distinct spatial difference; the total nitrogen content ranged from 127.2-2092.8 mg·kg-1 and total phosphorous content ranged from 222.1-528.4 mg·kg-1. Moreover, nitrogen loading (1033.6 mg·kg-1) in the vegetated zones were higher than in the unvegetated zones (325.2 mg·kg-1). In addition, carbohydrate (3.7 mg·g-1) was the dominant component of sedimentary bioclastic material, with lipids (2.8 mg·g-1) being the second most abundant of the biodegradable compounds. The major sources of nutrients and biodegradable compounds in the sediment were massive aggregates of macrophyte detritus. The pigment, nutrient, and biodegradable compound contents in the vegetated zones were significantly higher than in unvegetated zones (P<0.01). The benthic eutrophic state showed a trend from mesotrophic to eutrophic in Xukou Bay, which should be given more attention in the future management of freshwater lake ecosystems.


Assuntos
Ecossistema , Monitoramento Ambiental , Lagos , China , Eutrofização , Sedimentos Geológicos , Nitrogênio , Fósforo
14.
Environ Sci Pollut Res Int ; 26(33): 34510-34520, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31643015

RESUMO

The odor problem caused by the decay of aquatic plants is widespread in many freshwater lakes. In this study, the spatial distributions of seven taste and odor (T&O) compounds (dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, 2-methylisoborneol, geosmin, ß-cyclocitral, and ß-ionone) in the sediments and overlying water of the east of Taihu Lake were investigated. The effects of plant and physico-chemical parameters on the release of T&O compounds were also analyzed. The results showed that high concentrations of T&O compounds were detected in the area where Eichhornia crassipes was flourishing. Volatile organic sulfur compounds were not found in the water source area, which was not covered by aquatic plants. High plant biomass and aquiculture activities might increase the release of the taste and odor compounds. The correlation between the concentrations of odorous compounds and nutrients in the sediment was also analyzed. The production of odorants was positively correlated with the nitrogen, and they may migrate from sediment to overlying water. The result suggested that controlling the plant density and aquaculture activities could reduce the release of odorous compounds.


Assuntos
Organismos Aquáticos/química , Odorantes/análise , Plantas/química , Paladar , Aldeídos , China , Diterpenos , Sedimentos Geológicos/química , Lagos/química , Naftóis , Norisoprenoides , Sulfetos , Compostos Orgânicos Voláteis , Poluentes Químicos da Água/análise
15.
Bioresour Technol ; 294: 122160, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563112

RESUMO

In this study, alkaline fermentation was applied to promote organics and P recovery from polyaluminum chloride (PACl)-enhanced primary sedimentation sludge. Coagulant results demonstrated that the optimum PACl dosage of 100 mg/L resulted in the effective concentration of 73% of organic matter and 90% of P from wastewater into sludge. Batch fermentation results highlighted the ability of alkaline fermentation in improving the biodegradability of PACl sludge. More specifically, at pH 11, 43.3% of soluble organics and 36.49% of P were released to the fermentation supernatant. Furthermore, P fractionation fermented sludge results revealed that partial Al-P dissolution and organic phosphorus hydrolysis were the main drivers of the released P. Finally, at pH 11, 85% of P was recovered as magnesium ammonium phosphate from the fermentation supernatant at the 2:1 Mg/P molar ratio. In conclusion, 24.9% of organics and 27.9% of P from raw wastewater were converted to valuable products via alkaline fermentation.


Assuntos
Fósforo , Esgotos , Hidróxido de Alumínio , Fermentação , Concentração de Íons de Hidrogênio
16.
Bioresour Technol ; 293: 122068, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31479856

RESUMO

This work aimed to examine a permanent magnetic cation-exchange resin (MCER) for synergistic co-removal of Cu(II) and tetracycline (TC) from their mixed solutions. Batch adsorption experiments and characterizations were performed to elucidate the adsorption mechanisms. The adsorption of Cu(II) followed the Langmuir isotherm model in most cases, while Freundlich isotherm model was more suitable for fitting TC adsorption, which was due to the surface coordination between adsorbed Cu(II) and TC and the formation of multilayer MCER-Cu-TC complexes. The equilibrium TC adsorption amount in binary Cu/TC system was about 5.5-13.5 times of that in sole system, whereas Cu(II) uptake was nearly unchanged. Decomplexing-bridging was ascribed as the primary mechanism, which involved the [Cu-TC] decomplexing and [resin-Cu] bridging for TC uptake. Moreover, these MCER microbeads could be reused with negligible loss in adsorption capacity during five adsorption-desorption cycles, indicative of great potential in synergistic co-removal of organics-Cu complexes from aqueous solutions.


Assuntos
Cobre , Poluentes Químicos da Água , Adsorção , Resinas de Troca de Cátion , Cinética , Tetraciclina
17.
Environ Pollut ; 254(Pt A): 112954, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31398637

RESUMO

Organic matter-induced black bloom frequently occurs in a number of large eutrophic shallow lakes; this can result in the release of malodorous compounds and has a negative impact on water quality. In the study, a microcosm system containing Zizania latifolia (Z. latifolia), a common aquatic plant, was established and the release of seven taste and odour compounds, dimethyl sulphide (DMS), dimethyl disulphide (DMDS), dimethyl trisulphide (DMTS), 2-methylisoborneol (MIB), geosmin (GSM), ß-cyclocitral, and ß-ionone, was investigated. The results showed that these compounds were all detected during Z. latifolia decay, and that volatile organic sulphur compounds (VOSCs), such as DMS, DMDS, and DMTS, were the main factors responsible for the strong foul odour (the maximum reached 5.0 µg L-1). The release of odorous compounds was stronger during the initial seven days, and then progressively decreased in the middle stage of the experiment. Furthermore, large amounts of nutrients were released into the overlying water; nutrient concentration increased with increasing plant biomass. A positive correlation was observed between the odorant concentration and plant biomass. These results indicate that the density of aquatic plants should be controlled as part of future management of aquatic ecosystems.


Assuntos
Biodegradação Ambiental , Ecossistema , Odorantes/análise , Poaceae , Aldeídos , Diterpenos , Lagos , Naftóis , Norisoprenoides , Sulfetos , Paladar , Compostos Orgânicos Voláteis , Qualidade da Água
18.
CNS Neurol Disord Drug Targets ; 18(8): 621-630, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31389319

RESUMO

BACKGROUND & OBJECTIVE: Tenidap, a selective human inwardly rectifying potassium (Kir) 2.3 channel opener, has been reported to have antiepileptic effect in the pilocarpine temporal lobe epilepsy rat model in our previous study. However, the effect of tenidap on neurons and its relationship with the epileptiform bursting charges in neuron is still required to be explored. METHODS: In this study, cyclothiazide (CTZ) induced cultured hippocampal neuron epileptic model was used to study the antiepileptic effect of tenidap and the relationship between Kir2.3 channel and the neuronal epileptiform burst. RESULTS: Patch clamp recording showed that both acute (2h) and chronic (48h) CTZ pre-treatment all significantly induced robust epileptiform burst activities in cultured hippocampal neurons, and tenidap acutely application inhibited this highly synchronized abnormal activities. The effect of tenidap is likely due to increased activity of Kir2.3 channels, since tenidap significantly enhanced kir current recorded from those neurons. In addition, neurons overexpressing Kir2.3 channels, by transfection with Kir2.3 plasmid, showed a significant large increase of the Kir current, prevented CTZ treatment to induce epileptiform burst discharge. CONCLUSION: Our current study demonstrated that over activation of Kir2.3 channel in hippocampal neurons could positively interference with epileptiform burst activities, and tenidap, as a selective Kir2.3 channel opener, could be a potential candidate for seizure therapy.

19.
Environ Sci Pollut Res Int ; 26(29): 30348-30355, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31435908

RESUMO

Antibiotic residues pose a threat to the health of aquatic organisms. The effects and accumulation of antibiotic ciprofloxacin (CIP) in a floating macrophyte (Eichhornia crassipes) under hydroponic conditions were investigated. It was found that E. crassipes exposure to CIP (< 1000 µg L-1) could maintain a stable photosynthesis efficiency. In response to CIP stress, catalase and peroxidase activities of leaves were 7.24-37.51 nmol min-1 g-1 and 98.46-173.16 U g-1, respectively. The presence of CIP did not inhibit the growth of the plant. After 14 days of exposure, tender leaves became white and withered, ascribed to the decline of chlorophyll content and chlorophyll fluorescence parameters. The CIP concentrations, absorbed by E. crassipes, were highest in the roots, followed by white aerial parts and green aerial parts at CIP concentrations of 100 and 1000 µg L-1. These findings demonstrated that E. crassipes could absorb and tolerate CIP in a limited time-scale and imply an alternative solution for phytoremediation in water bodies contaminated with antibiotics.


Assuntos
Antibacterianos/análise , Organismos Aquáticos/efeitos dos fármacos , Ciprofloxacino/análise , Eichhornia/efeitos dos fármacos , Poluentes Químicos da Água/análise , Antibacterianos/metabolismo , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Biodegradação Ambiental , Clorofila/metabolismo , Ciprofloxacino/metabolismo , Ecotoxicologia , Eichhornia/crescimento & desenvolvimento , Eichhornia/metabolismo , Hidroponia , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Poluentes Químicos da Água/metabolismo
20.
Neuroscience ; 415: 18-30, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325561

RESUMO

Previous studies have focused on the effects of N-methyl-D-aspartate receptor (NMDAR) blockade on neonates, but little is known about the effect of the embryonic NMDAR blockade on offspring, especially the long-lasting effect, on behavior in adulthood. Here, pregnant rats at E14 were treated with ketamine for 5 successive days and undergone multiple behavior tests, electrophysiology experiment, and Western blotting analysis to detect the alterations in their offspring. We found that embryonic ketamine treatment induced anxiety-like behavior in adulthood (8-week old) offspring. At the same period, we observed an attenuation of NMDA-evoked current as well as decreased NR2A and NR2B membrane expression in the prefrontal cortex (PFC), but not in the hippocampus or amygdala. Selective inhibition experiments with NR2A or NR2B specific antagonists suggested that embryonic ketamine treatment induced NMDAR current attenuation was likely mediated by changes in NR2A subunit. Moreover, at the 4-week time point, NMDA-evoked current was unchanged in PFC, but enhanced in hippocampal CA1 area, which may be caused by the over expression of NR2B in the hippocampus at 4-week time. Furthermore, NR2B knockdown, by using NR2B-shRNA lentivirus, in the hippocampal CA1 area at 3-4-week of age significantly rescued the decrease in NR2A expression in the PFC and anxiety-like behavior observed at 8-week adult offspring rats. In conclusion, our results suggested that embryonic ketamine treatment induced anxiety-like behavior and the downregulation of NMDAR function in PFC in the adulthood period of offspring, which might result from the enhanced function of NMDARs in the hippocampus at the 4-week juvenile time point.

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