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1.
Artigo em Inglês | MEDLINE | ID: mdl-38836739

RESUMO

Objectives: Rheumatoid Arthritis (RA) can accelerate atherosclerosis (AS) plaque formation. High prevalence of AS has been demonstrated in early-stage RA patients. Therefore, there is an urgent need to investigate what mechanisms and key molecules accelerate AS in RA to improve the management of RA. Methods: We retrieved gene expression data for RA (GSE45291) and atherosclerosis (GSE28829) from Gene Expression Omnibus (GEO). Seventeen key genes were identified, and the top one candidate hub gene was SLAM family member 8 (SLAMF8). To investigate the role of SLAMF8 in AS and RA, U937 cells were differentiated into macrophages using Phorbol 12-myristate 13-acetate (PMA) and further transformed into foam cells by oxidized low-density lipoprotein (ox-LDL) treatment and siRNA was manipulated to knock down SLAMF8. Flow Cytometry was employed to assess cell state. The mRNA and protein expressions of the genes were investigated using western blot and RT-qPCR. Results: SLAMF8 was screened as a key gene by bioinformatic methods. Compared to Mφ, SLAMF8, TLR4 and inflammatory cytokines, tumor necrosis factor α (TNF-α), and Interleukin 6 (IL-6) were noticeably expressed in foam cells. Knockdown of SLAMF8 could remarkably curtail TLR4, TNF-α, and IL-6 protein levels. Antagonizing SLAMF8 could attenuate inflammatory factors and apoptosis of foam cells by inhibiting the TLR4 pathway, thus mitigating the severity of AS in RA. Conclusions: Our work demonstrated that SLAMF8 promoted AS in patients with RA by inducing inflammation and apoptosis of foam cells via TLR4 signaling. Therefore, SLAMF8 could be a possible therapeutic spot for AS in RA patients.

2.
New Phytol ; 238(3): 1004-1018, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36495263

RESUMO

To what degree plant ecosystems thermoregulate their canopy temperature (Tc ) is critical to assess ecosystems' metabolisms and resilience with climate change, but remains controversial, with opinions from no to moderate thermoregulation capability. With global datasets of Tc , air temperature (Ta ), and other environmental and biotic variables from FLUXNET and satellites, we tested the 'limited homeothermy' hypothesis (indicated by Tc & Ta regression slope < 1 or Tc < Ta around midday) across global extratropics, including temporal and spatial dimensions. Across daily to weekly and monthly timescales, over 80% of sites/ecosystems have slopes ≥1 or Tc > Ta around midday, rejecting the above hypothesis. For those sites unsupporting the hypothesis, their Tc -Ta difference (ΔT) exhibits considerable seasonality that shows negative, partial correlations with leaf area index, implying a certain degree of thermoregulation capability. Spatially, site-mean ΔT exhibits larger variations than the slope indicator, suggesting ΔT is a more sensitive indicator for detecting thermoregulatory differences across biomes. Furthermore, this large spatial-wide ΔT variation (0-6°C) is primarily explained by environmental variables (38%) and secondarily by biotic factors (15%). These results demonstrate diverse thermoregulation patterns across global extratropics, with most ecosystems negating the 'limited homeothermy' hypothesis, but their thermoregulation still occurs, implying that slope < 1 or Tc < Ta are not necessary conditions for plant thermoregulation.


Assuntos
Ecossistema , Plantas , Regulação da Temperatura Corporal , Temperatura , Mudança Climática
3.
Macromol Rapid Commun ; 42(18): e2100028, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33851449

RESUMO

Hydrogels with improved mechanical properties can expand to a greater range of applications. The fabrication of conventional toughened hydrogels typically requires precise modifications, multiple components, and complex steps. Here, a straightforward "one-step" polymerization method for the in situ preparation of hydrogels in aqueous solutions, is reported. Inspired by polymerization-induced self-assembly (PISA), water-miscible monomers are copolymerized during the hydrogel fabrication; the growing blocks eventually form physical bridges thus providing a mechanism for effective energy dissipation. The rheological and mechanical properties are evaluated and the results reveal that this strategy can be an effective approach to design mechanically enhanced hydrogels for a wide range of applications.


Assuntos
Hidrogéis , Água , Polimerização , Reologia
4.
Brief Bioinform ; 15(4): 637-47, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23396756

RESUMO

Bioinformatics is challenged by the fact that traditional analysis tools have difficulty in processing large-scale data from high-throughput sequencing. The open source Apache Hadoop project, which adopts the MapReduce framework and a distributed file system, has recently given bioinformatics researchers an opportunity to achieve scalable, efficient and reliable computing performance on Linux clusters and on cloud computing services. In this article, we present MapReduce frame-based applications that can be employed in the next-generation sequencing and other biological domains. In addition, we discuss the challenges faced by this field as well as the future works on parallel computing in bioinformatics.


Assuntos
Biologia Computacional , Coleta de Dados , Linguagens de Programação
5.
Sensors (Basel) ; 15(9): 23218-48, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26389903

RESUMO

Data gathering is a key operator for applications in wireless sensor networks; yet it is also a challenging problem in mobile sensor networks when considering that all nodes are mobile and the communications among them are opportunistic. This paper proposes an efficient data gathering scheme called ADG that adopts speedy mobile elements as the mobile data collector and takes advantage of the movement patterns of the network. ADG first extracts the network meta-data at initial epochs, and calculates a set of proxy nodes based on the meta-data. Data gathering is then mapped into the Proxy node Time Slot Allocation (PTSA) problem that schedules the time slots and orders, according to which the data collector could gather the maximal amount of data within a limited period. Finally, the collector follows the schedule and picks up the sensed data from the proxy nodes through one hop of message transmissions. ADG learns the period when nodes are relatively stationary, so that the collector is able to pick up the data from them during the limited data gathering period. Moreover, proxy nodes and data gathering points could also be timely updated so that the collector could adapt to the change of node movements. Extensive experimental results show that the proposed scheme outperforms other data gathering schemes on the cost of message transmissions and the data gathering rate, especially under the constraint of limited data gathering period.

6.
Environ Pollut ; 350: 124015, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657892

RESUMO

Water security remains a critical issue given the looming threats of industrial pollution, necessitating comprehensive assessments of water quality to address seasonal fluctuations and influential factors while formulating effective strategies for decision makers. This study introduces a novel approach for evaluating water quality within a complex riverine zone in South Korea: Han River that encompasses five river streams situated at each junction of North and South streams (including Gyeongan Stream) that ultimately leading towards Paldang Lake. By utilizing the monthly water characteristic data from the year 2013-2022 across 14 different locations, the significant seasonal trends and potential influences on water quality are identified. The water quality here is calculated with the proposed method of sub-index water quality index (s-WQI). A combinatorial prediction approach of s-WQI for each location is conducted through a collective of data preprocessing approaches including Hampel filtering and feature selection in prior to the machine learning predictions. In return, light gradient boosting (LGB) is the most accurate predictor by outperforming other prediction algorithms, especially through LGB-Pearson and LGB-Spearman combinations for North and South stream intersections, and LGB-Pearson for Paldang Lake. To further evaluate the robustness of this evaluation and extending the results to a foreseeable scenario, a seasonal based Monte-Carlo Simulation with 10,000 attempts targeting the water characteristic distributions obtained from each location considered are carried out to identify the risk bounds within. The results are further interpreted with SHAP analysis on identifying the contributions of each water characteristics towards the water quality through local and global spectrum. This research yields practical implications, offering tailored strategies for water quality enhancement and early warning systems. The integration of AI-based prediction and feature selection underscores the transformative potential of computational techniques in advancing data-driven water quality assessments, shaping the future of environmental science research.


Assuntos
Monitoramento Ambiental , Rios , Qualidade da Água , Rios/química , Monitoramento Ambiental/métodos , República da Coreia , Análise Espaço-Temporal , Aprendizado de Máquina , Poluentes Químicos da Água/análise , Estações do Ano , Poluição da Água/estatística & dados numéricos
7.
Sci Total Environ ; 947: 174426, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969123

RESUMO

Photosynthesis provides carbon sources and energy for crop growth and development, and the widespread presence of microplastics and plastic plasticisers in agricultural soils affects crop photosynthesis, but the mechanism of the effect is not clear. This study aims to investigate the effects of different microplastics and plasticizers on cucumber photosynthesis. Using polyvinyl chloride (PVC), polyethylene (PE), polystyrene (PS), and di-n-octyl phthalate (DOP) as representative microplastics and plasticizers, we assessed their impact on cucumber photosynthesis. Our results reveal significant alterations in key parameters: intercellular CO2 concentration (Ci) and transpiration rate (Tr) increased across all treatments, whereas stomatal limit value (Ls) and water use efficiency (WUE) decreased. Notably, PS + DOP treatment led to a significant reduction in the maximum efficiency of photosystem II (Fv/Fm) and ATP accumulation. Furthermore, PE and PS + DOP treatments decreased lycopene and ɛ-carotene synthesis rates, as well as abscisic acid (ABA) accumulation. All treatments inhibited the conversion of ß-carotene into strigolactone (SL) and decreased chlorophyll synthesis rates, with PS + DOP exhibiting the most severe impact. Regarding chlorophyll degradation pathways, PVC and PE treatments reduced chlorophyll decomposition rates, whereas DOP with PS promoted degradation. PE and PS treatments also impaired light energy capture, electron transport, and the structural stability of photosystems I and II, as well as photosynthetic capacity and NADPH and ATP synthesis rates. Our findings underscore the differential impacts of microplastics and plasticizers on cucumber photosynthesis, with PS + DOP having the most detrimental effect. These results shed light on the complex interactions between microplastics and plant physiology, highlighting the urgent need for mitigation strategies in agricultural practices to safeguard crop productivity and environmental sustainability.

8.
RSC Adv ; 14(28): 20339-20350, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38932982

RESUMO

Four benzophenones, three dihydrocoumarins, and two coumarins were synthesised by a 1-3 step reaction, with yields ranging from 6.2 to 35%. Next, we investigated the in vitro antitumour activity of these compounds. Compounds 1, 8, and 9 exhibited strong antitumour activity and were considered promising candidates in this field. In particular, compound 1 exhibited very strong inhibitory activity against HL-60, A-549, SMMC-7721, and SW480 cells, with IC50 values of 0.48, 0.82, 0.26, and 0.99 µM, respectively. Finally, the antitumour mechanism of compound 1 was investigated through network pharmacology and molecular docking analyses, which identified 22 key genes and 21 tumour pathways. AKT1, ALB, CASP3, ESR1, GAPDH, HSP90AA1, and STAT3 were considered as potential target hub genes for compound 1. These results will enable the future development of benzophenone and its derivatives.

9.
Molecules ; 18(2): 2052-60, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23385341

RESUMO

The aim of this study was to investigate novel chalcones with potent anti-inflammatory activities in vivo. Chalcone and two chalcone analogues (compound 5 and 9) were evaluated using a caudal fin-wounded transgenic zebrafish line "Tg(mpx:gfp)" to visualize the effect of neutrophil recruitment dynamically. Results showed that treatment with compound 9 not only affected wound-induced neutrophil recruitment, but also affected Mpx enzymatic activity. Moreover, protein expression levels of pro-inflammatory factors (Mpx, NFκB, and TNFα) were also regulated by compound 9. Taken together, our results provide in vivo evidence of the anti-inflammatory effects of synthesized chalcone analogues on wound-induced inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Chalcona/análogos & derivados , Chalcona/farmacologia , Peixe-Zebra/metabolismo , Nadadeiras de Animais/cirurgia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Chalcona/síntese química , Chalcona/química , Larva/efeitos dos fármacos , Larva/enzimologia , Modelos Animais , Infiltração de Neutrófilos/efeitos dos fármacos , Peroxidase/metabolismo , Cicatrização/efeitos dos fármacos
10.
IEEE Trans Neural Netw Learn Syst ; 34(9): 5354-5365, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35500078

RESUMO

Trajectory planning is one of the indispensable and critical components in robotics and autonomous systems. As an efficient indirect method to deal with the nonlinear system dynamics in trajectory planning tasks over the unconstrained state and control space, the iterative linear quadratic regulator (iLQR) has demonstrated noteworthy outcomes. In this article, a local-learning-enabled constrained iLQR algorithm is herein presented for trajectory planning based on hybrid dynamic optimization and machine learning. Rather importantly, this algorithm attains the key advantage of circumventing the requirement of system identification, and the trajectory planning task is achieved with a simultaneous refinement of the optimal policy and the neural network system in an iterative framework. The neural network can be designed to represent the local system model with a simple architecture, and thus it leads to a sample-efficient training pipeline. In addition, in this learning paradigm, the constraints of the general form that are typically encountered in trajectory planning tasks are preserved. Several illustrative examples on trajectory planning are scheduled as part of the test itinerary to demonstrate the effectiveness and significance of this work.

11.
J Colloid Interface Sci ; 645: 493-501, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37159991

RESUMO

Improving the performance of proton exchange membranes (PEMs) through the synthesis of sulfonated polymers with elaborate molecular structures has received extensive approval. However, the tedious synthetic process and consequently high costs restrain their possible substitution for Nafion, a classic PEM material. Herein, a series of semi-crystalline sulfonated poly(ether ketone)s with fluorene-based units were prepared via direct copolymerization of commercially available monomers and followed post-sulfonation, namely SPEK-FD-x, where × represents the molar ratio of the fluorene-containing monomer to the employed bisphenol monomers. The entire synthetic pathway was facile without involving hardly accessible materials. Subsequently, various properties of SPEK-FD-x membranes were investigated and further compared with Nafion 117. Due to the formation of the well-defined hydrophilic-hydrophobic microphase separation morphology and the reinforcement of the PEK crystalline regions, the SPEK-FD-x membranes exhibited outstanding proton conductivity, resistance for methanol permeation, as well as dimensional, thermal, oxidative, and mechanical stability. Among them, the overall behavior of the SPEK-FD-25 membrane was comparable to or even greater than that of Nafion 117, most importantly, it also performed decently in both H2/air fuel cells and direct methanol fuel cells. Therefore, with the straightforward synthesis and superior performance, the SPEK-FD-x membranes may serve as a promising alternative to Nafion.

12.
ACS Appl Mater Interfaces ; 15(36): 42603-42610, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37639524

RESUMO

Organic materials have garnered intensive focus as a new group of electrodes for lithium-ion batteries (LIBs). However, many reported organic electrodes so far still exhibit unsatisfying cycling stability because of the dissolution in the electrolytes. Herein, a novel azo-linked hexaazatrianphthalene (HATN)-based polymer (AZO-HATN-AQ) is designed and fabricated by the polymerization of trinitrodiquinoxalino[2,3-a:2',3'-c]phenazine (HATNTN) and 2,6-diaminoanthraquinone (DAAQ). The abundant redox-active sites, extended π-conjugated planar conformation, and low energy gap endow the AZO-HATN-AQ electrode with high theoretical capacity, excellent solubility resistance, and fast Li-ion transport. In particular, the fully lithiated AZO-HATN-AQ still keeps the planar structure, contributing to the excellent cycling stability. As a result, AZO-HATN-AQ cathodes show high specific capacity (240 mAh g-1 at 0.05 A g-1), prominent rate capability (98 mAh g-1 at 8 A g-1), and outstanding cycling stability (120 mAh g-1 after 2000 cycles at 4 A g-1 with 85.7% capacity retention) simultaneously. This study demonstrates that rational structure design of the polymer electrodes is an effective approach to achieving excellent comprehensive electrochemical performance.

13.
IEEE Trans Neural Netw Learn Syst ; 34(9): 5255-5267, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37015565

RESUMO

The Hamilton-Jacobi-Bellman (HJB) equation serves as the necessary and sufficient condition for the optimal solution to the continuous-time (CT) optimal control problem (OCP). Compared with the infinite-horizon HJB equation, the solving of the finite-horizon (FH) HJB equation has been a long-standing challenge, because the partial time derivative of the value function is involved as an additional unknown term. To address this problem, this study first-time bridges the link between the partial time derivative and the terminal-time utility function, and thus it facilitates the use of the policy iteration (PI) technique to solve the CT FH OCPs. Based on this key finding, the FH approximate dynamic programming (ADP) algorithm is proposed leveraging an actor-critic framework. It is shown that the algorithm exhibits important properties in terms of convergence and optimality. Rather importantly, with the use of multilayer neural networks (NNs) in the actor-critic architecture, the algorithm is suitable for CT FH OCPs toward more general nonlinear and complex systems. Finally, the effectiveness of the proposed algorithm is demonstrated by conducting a series of simulations on both a linear quadratic regulator (LQR) problem and a nonlinear vehicle tracking problem.

14.
Adv Sci (Weinh) ; 10(25): e2302654, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37381631

RESUMO

Special separation membranes are widely employed for separation and purification purposes under challenging operating conditions due to their low energy consumption, excellent solvent, and corrosion resistance. However, the development of membranes is limited by corrosion-resistant polymer substrates and precise interfacial separation layers. Herein, polyaniline (PANI) is employed to achieve insitu anchoring of multiple interfaces, resulting in the fabrication of polyaniline@graphene oxide/polyether ether ketone (PANI@GO/PEEK) membranes. Insitu growth of PANI achieves the adequate bonding of the PEEK substrate and GO separation interface, which solves the problem of solution processing of PEEK and the instability of GO layers. By bottom-up confined polymerization of aniline, it could control the pore size of the separation layer, correct defects, and anchor among polymer, nano-separation layer, and nano-sheet. The mechanism of membrane construction within the confined domain and micro-nano structure modulation is further explored. The membranes demonstrate exceptional stability realizing over 90% rejection in 2 m HCl, NaOH, and high temperatures. Additionally, -membranes exhibit remarkable durability after 240 days immersion and 100 h long-term operation, which display the methanol flux of 50.2 L m-2 h-1 and 92% rejection of AF (585 g mol-1 ). This method substantially contributes to special separation membranes by offering a novel strategy.

15.
Drug Chem Toxicol ; 35(3): 341-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22289409

RESUMO

We used ultraviolet (UV)-induced fin damage in zebrafish as a system for evaluating the chemopreventive potential of flavonoids. Chemopreventive effects of each compound, including flavone, flavanone, and chalcone, on fin development were evaluated using Kaplan-Meier analysis and Cox proportional hazards regression. Results showed that 1) flavone has the highest capacity to protect zebrafish fins from UV-induced damages among other groups; 2) zebrafish fins in the UV+1 ppm flavone group are 1.02~9.60 times more likely to return to normal fins than ones in the UV-only group, but fins in the UV+20 ppm flavone group are only 0.45~5.66 times more likely to recover; and 3) flavone significantly reduced ROS production in UV-exposed zebrafish embryos, which may attenuate UV-mediated apoptosis. In conclusion, zebrafish can be used as a system for comparing the UV-protection efficacy of flavonoids.


Assuntos
Nadadeiras de Animais/efeitos dos fármacos , Nadadeiras de Animais/efeitos da radiação , Flavonas/farmacologia , Lesões Experimentais por Radiação/prevenção & controle , Raios Ultravioleta , Peixe-Zebra/embriologia , Animais , Apoptose/efeitos da radiação , Chalcona/química , Chalcona/farmacologia , Flavanonas/química , Flavanonas/farmacologia , Flavonas/química , Marcação In Situ das Extremidades Cortadas , Estimativa de Kaplan-Meier , Estrutura Molecular , Modelos de Riscos Proporcionais , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Molecules ; 17(7): 8206-16, 2012 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-22777189

RESUMO

We described herein a concise synthesis of 3',4'-diaminoflavone 10. This new, three-step synthetic approach is more efficient than the conventional seven-step synthetic method. The route is shortened significantly by introducing the amino moieties early and eliminating the need for nitro group reduction. The other two analogues, 5,7-dihydroxy-3',4'-diaminoflavone 11 and 5,7-dimethoxy-3',4'-diaminoflavone 12, were also synthesized similarly. The above three compounds, along with flavone, were evaluated for their antioxidant and UVB-protection abilities on zebrafish larvae. The data showed that compound 10 exhibited the best result, with -102.3% of ROS-scavenging rate.


Assuntos
Antioxidantes/síntese química , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Flavonas/síntese química , Flavonas/farmacologia , Peixe-Zebra/metabolismo , Animais , Antioxidantes/química , Apoptose/efeitos da radiação , Citoproteção/efeitos dos fármacos , Citoproteção/efeitos da radiação , Flavonas/química , Sequestradores de Radicais Livres/farmacologia , Larva/citologia , Larva/efeitos dos fármacos , Larva/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta
17.
J Colloid Interface Sci ; 610: 905-912, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34865743

RESUMO

Membrane fouling during the use of separation membrane has always been the main reason for the degradation of membrane performance. The traditional solution is complicated and inefficient, so we proposed multi-step integration method to prepare antifouling zwitterionic poly(aryl ether sulfone) (PAES-Z-x) ultrafiltration (UF) membrane with higher efficiency. We designed and synthesized a bisphenol precursor containing tertiary amine groups, which could provide reactive sites for grafting zwitterionic group. Afterwards, the zwitterionic modified UF membrane was prepared by graft copolymerization and non-solvent-induced phase separation (NIPS). The morphology, hydrophilicity, water flux and rejection of the PAES-Z-x membrane could be optimized by tuning zwitterion content. The hydration layer formed by zwitterions effectively reduced the adsorption of proteins and endowed the membrane good antifouling properties. The resulting membrane showed the pure water flux increased (up to 311 L m-2h-1 bar-1), high bovine serum albumin (BSA) rejection (97%) and good water flux recovery ratio (FRR) (82.8%). Zwitterionic antifouling PAES UF membrane prepared by a simple and effective method provided a new direction for improving PAES UF membrane's antifouling performance.


Assuntos
Incrustação Biológica , Incrustação Biológica/prevenção & controle , Membranas Artificiais , Soroalbumina Bovina , Sulfonas , Ultrafiltração
18.
Adv Sci (Weinh) ; 9(2): e2102439, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34761546

RESUMO

Scintillators, which can convert high-energy ionizing radiation into visible light, have been serving as the core component in radiation detectors for more than a century of history. To address the increasing application demands along with the concern on nuclear security, various strategies have been proposed to develop a next-generation scintillator with a high performance in past decades, among which the novel approach via structure control has received great interest recently due to its high feasibility and efficiency. Herein, the concept of "structure engineering" is proposed for the exploration of this type of scintillators. Via internal or external structure design with size ranging from micro size to macro size, this promising strategy cannot only improve scintillator performance, typically radiation stopping power and light yield, but also extend its functionality for specific applications such as radiation imaging and therapy, opening up a new range of material candidates. The research and development of various types of structured scintillators are reviewed. The current state-of-the-art progresses on structure design, fabrication techniques, and the corresponding applications are discussed. Furthermore, an outlook focusing on the current challenges and future development is proposed.

19.
Sci Total Environ ; 803: 149868, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34481163

RESUMO

To investigate the mechanisms and potential risks of river eco-remediation, river water, sediment, and biofilms in remediation facilities were sampled from a 2-year full scale eco-remediation site in an urban river in southeastern China. The samples from both remediated and adjacent control areas were analyzed for chemical properties and functional microbial community structures. The eco-remediation significantly changed the community structures in the river and introduced much more diverse functional microorganisms in facility biofilms. Corresponding to effective reduction of organics and ammonium in river water, some labile-organics-degrading and ammonia-oxidizing gene families showed higher abundances in river water of remediated area than control area, and were obviously more abundant in facility biofilms than in river water and sediment. The eco-remediation facilities showed obvious absorption of N, P, and heavy metals (Mn, CrVI, Fe, Al, As, Co), contributing to nutrients and metals removal from river water. The eco-remediation also increased transparency and sedimentation of some heavy metals (Cu, Pb, Zn), which probably associated with colloids breakdown. Various metal-resistance microorganisms showed different abundances between facility biofilms and sediment, in accordance with relative metals. Most detected pathogens were not significantly affected by eco-remediation. However, our measurements in sediment and facilities showed heavy metals accumulation and development of some pathogens and several antibiotic-resistance pathogens, alerting us to investigate and control these potential risks to ecosystem and human health.


Assuntos
Metais Pesados , Microbiota , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Rios , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Adv Sci (Weinh) ; 9(1): e2103706, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34766471

RESUMO

Confined polymerization is an effective method for precise synthesis, which can further control the micro-nano structure inside the composite material. Polyaniline (PANI)-based composites are usually prepared by blending and original growth methods. However, due to the strong rigidity and hydrogen bonding of PANI, the content of PANI composites is low and easy to agglomerate. Here, based on confined polymerization, it is reported that polyaniline /polyether ether ketone (PANI/PEEK) film with high PANI content is synthesized in situ by a one-step method. The micro-nano structure of the two polymers in the confined space is further explored and it is found that PANI grows in the free volume of the PEEK chain, making the arrangement of the PEEK chain more orderly. Under the best experimental conditions, the prepared 16 µm-PANI/PEEK film has a dielectric constant of 205.4 (dielectric loss 0.401), the 75 µm-PANI/PEEK film has a conductivity of 3.01×10-4 S m-1 . The prepared PANI/PEEK composite film can be further used as electronic packaging materials, conductive materials, and other fields, which has potential application prospects in anti-static, electromagnetic shielding materials, corrosion resistance, and other fields.

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