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1.
Adv Mater ; 36(26): e2313209, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38591644

RESUMO

Metal nanoparticle (NP) cocatalysts are widely investigated for their ability to enhance the performance of photocatalytic materials; however, their practical application is often limited by the inherent instability under light irradiation. This challenge has catalyzed interest in exploring high-entropy alloys (HEAs), which, with their increased entropy and lower Gibbs free energy, provide superior stability. In this study, 3.5 nm-sized noble-metal-free NPs composed of a FeCoNiCuMn HEA are successfully synthesized. With theoretic calculation and experiments, the electronic structure of HEA in augmenting the catalytic CO2 reduction has been uncovered, including the individual roles of each element and the collective synergistic effects. Then, their photocatalytic CO2 reduction capabilities are investigated when immobilized on TiO2. HEA NPs significantly enhance the CO2 photoreduction, achieving a 23-fold increase over pristine TiO2, with CO and CH4 production rates of 235.2 and 19.9 µmol g-1 h-1, respectively. Meanwhile, HEA NPs show excellent stability under simulated solar irradiation, as well high-energy X-ray irradiation. This research emphasizes the promising role of HEA NPs, composed of earth-abundant elements, in revolutionizing the field of photocatalysis.

2.
Adv Sci (Weinh) ; 11(17): e2400099, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38417112

RESUMO

Metal sulfide-based homojunction photocatalysts are extensively explored with improved photocatalytic performance. However, the construction of metal sulfide-based S-scheme homojunction remains a challenge. Herein, the fabrication of 2D CdIn2S4 nanosheets coated 3D CdIn2S4 octahedra (referred to as 2D/3D n-CIS/o-CIS) S-scheme homojunction photocatalyst is reported by simply adjustment of polyvinyl pyrrolidone amount during the solvothermal synthesis. The formation of S-scheme homojunction within n-CIS/o-CIS is systematically investigated via a series of characterizations, which can generate an internal electric field to facilitate the separation and migration of photogenerated electron-hole pairs. The 2D/3D n-CIS/o-CIS composite exhibits significantly improved photocatalytic activity and stability in the selective oxidation of phenylcarbinol (PhCH2OH) to benzaldehyde (PhCHO) when compared to pure n-CIS and o-CIS samples under visible light irradiation. It is hoped that this work can contribute novel insights into the development of metal sulfides S-scheme homojunction photocatalysts for solar energy conversion.

3.
Chem Commun (Camb) ; 60(21): 2914-2917, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38372145

RESUMO

Nickel-based electrocatalysts for water oxidation suffer from low activity and poor stability. In this work, 0.015 mg cm-2 TiO2 nanosheets anchored on Ni foam addressed these problems after electrochemical activation. In situ investigations, including Raman spectra, corroborated the enhanced generation of highly active Ni(III)-O-O species on Ni foam in the presence of trace TiO2.

4.
Water Res ; 249: 121008, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38096729

RESUMO

Phytoremediation, which is commonly carried out through hydroponics and substrate-based strategies, is essential for the effectiveness of nature-based engineered solutions aimed at addressing excess nitrogen in aquatic ecosystems. However, the performance and mechanisms of plants involving nitrogen removal between different strategies need to be deeply understood. Here, this study employed in-situ cultivation coupled with static nitrogen tracing experiments to elucidate the influence of both strategies on plant traits associated with nitrogen removal. The results indicated that removal efficiencies in plants with substrate-based strategies for ammonium nitrogen and nitrate nitrogen were 30.51-71.11 % and 16.82-99.95 %, respectively, which were significantly higher than those with hydroponics strategies (25.98-58.18 % and 7.29-79.19 %, respectively). Similarly, the plant nitrogen uptake rates in the substrate-based strategy also generally showed higher levels compared to hydroponics strategies (P < 0.05). Meanwhile, the microorganisms-mediated nitrous oxide emission rates in the substrate-based strategy during summer (unamended: 0.00-0.58 µg/g/d; potential: 3.35-7.65 µg/g/d) were obviously lower than those in the hydroponics strategy (unamended: 2.23-11.70 µg/g/d; potential: 9.72-43.09 µg/g/d) (P < 0.05). Notably, analysis of similarity tests indicated that the influences of strategy on the above parameters generally surpass the effects attributable to interspecies plant differences, particularly during summer (R > 0, P < 0.05). Based on statistical and metagenomic analyses, this study revealed that these differences were driven by the stabilizing influence of substrate-based strategy on plant roots and enhancing synergistic interplay among biochemical factors within plant-root systems. Even so, phytoremediation strategies did not significantly alter the characteristics of plants with regards to their tendency towards ammonium nitrogen uptake (up to 87.68 %) and dissimilatory nitrate reduction to ammonium as primary biological pathway for nitrogen transformation which accounted for 53.66-96.47 % nitrate removal. In summary, this study suggested that the substrate-based strategy should be a more effective strategy for enhancing the nitrogen removal ability of plants in subtropical river restoration practices.


Assuntos
Compostos de Amônio , Nitratos , Ecossistema , Biodegradação Ambiental , Rios , Nitrogênio/metabolismo , Desnitrificação
5.
Water Res ; 246: 120737, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37857011

RESUMO

Reliable and cost-effective methods for monitoring microbial activity are critical for process control in wastewater treatment plants. The dehydrogenase activity (DHA) test has been recognized as an efficient measure of biological activity due to its simplicity and broad applicability. Nevertheless, the existing DHA test methods suffer from imperfections and are difficult to implement as routine monitoring techniques. In this work, an accurate and cost-effective modified DHA approach was developed and the procedure for the DHA test was critically evaluated with respect to the standard construction, sample pretreatment, incubation and extraction conditions. The feasibility of the modified DHA test was demonstrated by comparison with the oxygen uptake rate and adenosine triphosphate in a sequencing batch reactor. The sensitivities of the two typical tetrazolium salts to toxicant inhibition by heavy metals and antibiotics were compared, revealing that 2,3,5-triphenyltetrazolium chloride (TTC) exhibited a higher sensitivity. Furthermore, the sensitivity mechanism of the two DHA tests was elucidated through electrochemical experiments, theoretical analysis and molecular simulations. Both tetrazolium salts were found to be effective artificial electron acceptors due to their low redox potentials. Molecular docking simulations revealed that TTC could outperform other tetrazolium salts in accepting electrons and hydrogens from dehydrogenase. Overall, the modified DHA approach presents an accurate and cost-effective way to measure microbial activity, making it a practical tool for wastewater treatment plants.


Assuntos
Antibacterianos , Purificação da Água , Simulação de Acoplamento Molecular , Sais de Tetrazólio/química , Sais de Tetrazólio/farmacologia , Antibacterianos/farmacologia , Oxirredutases
6.
Environ Pollut ; 337: 122619, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37757937

RESUMO

To comprehensively understand antibiotic resistant genes (ARGs) profile in the subtropical drinking water river-reservoir system, this study selected Dongzhen river-reservoir system in Mulan Creek as object to investigate the spatial-temporal characteristics of ARGs diversity, bacterial host and resistance mechanism, and to analyze the key environmental factors driving ARGs profile variation. The results indicated that a total of 440 ARGs were detected in the target system, and the ARGs distribution pattern in the reservoir was attributed to autologous evolution or the comprehensive influence of feeding river system. The predominant bacterial host at different sites showed similar variations to dominated ARGs, and Proteobacteria, Actinobacteria and Bacteroidetes harbored most ARGs at phylum level, which showed the highest proportions of 74%, 37% and 35%, respectively. Antibiotic efflux was the primary resistance mechanism in all samples from wet season (45%-60%), yet the samples from dry season exhibited multiple resistance mechanisms, including inactivation (37%-52%), efflux (44%), and target alteration (43%). The total relative abundances of ARGs in the target system ranged from 0.89 × 10-2 to 1.71 × 10-2, and seasonal variation had a more significant influence on ARGs abundance than spatial variation (R = 0.68, P < 0.01). Environmental factors analysis indicated that the concentrations of nitrite nitrogen and total organic carbon were significant factors explaining ARGs number and various resistance mechanism proportions (P < 0.01), accounting for 48.7% and 61.1% of the variation, respectively; ammonia nitrogen concentration, total organic carbon concentration, temperature and pH were the significant influence factors on the relative abundance of ARGs (P < 0.05), with standardized regression weights of 0.700, 1.414, 1.447, and 1.727, respectively. In summary, in the surface water of the target system, ARGs diversity was primarily driven by ARGs horizontal transfer and antibiotics biosynthesis. Nutrients mainly promoted ARGs abundance by providing abundant energy, rather than increasing bacterial reproductive capacity.


Assuntos
Água Potável , Genes Bacterianos , Rios , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , Carbono , Nitrogênio
7.
Environ Res ; 237(Pt 2): 116999, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37634690

RESUMO

To understand the dynamics of planktonic microbial community and its metabolism processes in subtropical drinking water river-reservoir system with lower man-made pollution loading, this study selected Dongzhen river-reservoir system in Mulan Creek as object to investigate spatial-temporal characteristics of community profile and functional genes involved in biological metabolism, and to analyze the influence of environmental factors. The results indicated that Proteobacteria and Actinobacteria were the most diverse phyla with proportion ranges of 9%-80% in target system, and carbohydrate metabolism (5.76-7.12 × 10-2), amino acid metabolism (5.78-7.21 × 10-2) and energy metabolism (4.07-5.17 × 10-2) were found to be the dominant pathways of biological metabolism. Although there were variations in biological properties both spatially and temporally, seasonal variation had a greater influence on microbial community and biological metabolism, than locational differences. Regarding the role of environmental factors, this study revealed that microbial diversity could be affected by multiple abiotic factors, with total organic carbon, total phosphorus and temperature being more influential (absolute value of standardized regression weights >2.13). Stochastic processes dominated the microbial community assembly (R2 of neutral community model = 0.645), while niche-based processes differences represented by nutrients, temperature and pH level played secondary roles (R > 0.388, P < 0.01). Notably, the synergistic influences among the environmental factors accounted for the higher percentages of community variation (maximum proportion up to 17.6%). Additionally, pH level, temperature, and concentrations of dissolved oxygen, carbon and nitrogen were found to be the significant factors affecting carbon metabolism pathways (P < 0.05), yet only total organic carbon significantly affected on nitrogen transformation (P < 0.05). In summary, the microbial profile in reservoir is not completely dominated by that in feeding river, and planktonic microbial community and its metabolism in subtropical drinking water river-reservoir system are shaped by multiple abiotic and biotic factors with underlying interactions.

8.
Bioresour Technol ; 385: 129381, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37352992

RESUMO

This study aims at evaluating two-phase and single-phase reactors for treating sulfate wastewater with low COD/SO42- ratios. Additionally, a new process of gas stripping in an acidogenesis phase is proposed to reduce hydrogen sulfide (H2S) inhibition and enhance biomethanation. The two-phase performed better than the single-phase in terms of COD removal, CH4 production and H2S resistance. After 30 days of stripping, the COD and sulfate degradation rates increased from 85.16% to 91.09% and from 49.39% to 63.07% in the two-phase, respectively. In contrast, without stripping, they were from 79.21% to 64.37% and from 50.26% to 53.15% in the single-phase, respectively. The microbial biodiversity was augmented via stripping, including norank_f__Spirochaetaceae, Petrimonas, Desulfurella and Blvii28_wastewater-sludge_group. Stripping operation enhanced the dissimilatory sulfate reduction, amino acid metabolism and possibly sulfate-dependent anaerobic ammonia oxidation (S-ANAMMOX). This study provides a promising strategy to improve sulfate reduction and reduce H2S inhibition under a low COD/SO42- ratio.


Assuntos
Sulfeto de Hidrogênio , Águas Residuárias , Anaerobiose , Eliminação de Resíduos Líquidos , Oxirredução , Sulfatos/metabolismo , Reatores Biológicos
9.
J Hazard Mater ; 443(Pt A): 130130, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36265379

RESUMO

With rapid urbanization, microplastics and natural organic matters (NOMs) are ubiquitous in aquatic environment, and microplastics could act as carriers for organic matters in the aqueous solution and may pose a potential risk. In this study, the adsorption behaviors and mechanism of typical NOM, humic acid (HA), on polyvinyl chloride (PVC) and polystyrene (PS) microplastics were investigated. Various influence factors such as solution pH, ions species and concentrations, particle size, and coexisting surfactants were studied. The results suggested that HA adsorption onto PVC and PS was low pH-dependent, and ion species and concentrations have a significant impact on the adsorption capacity. In addition, the particle size of PVC and PS microplastics exhibited a significant correlation with HA adsorption, and the adsorption process was influenced by the surfactant species and concentrations. Moreover, the adsorption behaviors of HA in different real water environments were tested, and UV aging exhibited the opposite effects on adsorption capacity of PVC and PS. Furthermore, the adsorption mechanisms of HA onto PVC and PS were explored, indicating halogen bonding, hydrogen bonding, and π-π interaction play important roles in the adsorption process.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Adsorção , Cinética , Cloreto de Polivinila , Poluentes Químicos da Água/análise , Substâncias Húmicas/análise , Água , Poliestirenos , Tensoativos , Íons
10.
JAMA ; 328(8): 728-736, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35997729

RESUMO

Importance: Concurrent chemoradiotherapy has been the standard treatment for stage II nasopharyngeal carcinoma (NPC) based on data using 2-dimensional conventional radiotherapy. There is limited evidence for the role of chemotherapy with use of intensity-modulated radiation therapy (IMRT). Objective: To assess whether concurrent chemotherapy can be safely omitted for patients with low-risk stage II/T3N0 NPC treated with IMRT. Design, Setting, and Participants: This multicenter, open-label, randomized, phase 3, noninferiority clinical trial was conducted at 5 Chinese hospitals, including 341 adult patients with low-risk NPC, defined as stage II/T3N0M0 without adverse features (all nodes <3 cm, no level IV/Vb nodes; no extranodal extension; Epstein-Barr virus DNA <4000 copies/mL), with enrollment between November 2015 and August 2020. The final date of follow-up was March 15, 2022. Interventions: Patients were randomly assigned to receive IMRT alone (n = 172) or concurrent chemoradiotherapy (IMRT with cisplatin, 100 mg/m2 every 3 weeks for 3 cycles [n = 169]). Main Outcomes and Measures: The primary end point was 3-year failure-free survival (time from randomization to any disease relapse or death), with a noninferiority margin of 10%. Secondary end points comprised overall survival, locoregional relapse-free survival, distant metastasis-free survival, adverse events, and health-related quality of life (QOL) measured by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (QLQ-C30; range, 0-100 points; minimum clinically important difference ≥10 for physical function, symptom control, or health-related QOL; higher score indicates better functioning and global health status or worse symptoms). Results: Among 341 randomized patients (mean [SD] age, 48 [10] years; 30% women), 334 (98.0%) completed the trial. Median follow-up was 46 months (IQR, 34-58). Three-year failure-free survival was 90.5% for the IMRT-alone group vs 91.9% for the concurrent chemoradiotherapy group (difference, -1.4%; 1-sided 95% CI, -7.4% to ∞; P value for noninferiority, <.001). No significant differences were observed between groups in overall survival, locoregional relapse, or distant metastasis. The IMRT-alone group experienced a significantly lower incidence of grade 3 to 4 adverse events (17% vs 46%; difference, -29% [95% CI, -39% to -20%]), including hematologic toxicities (leukopenia, neutropenia) and nonhematologic toxicities (nausea, vomiting, anorexia, weight loss, mucositis). The IMRT-alone group had significantly better QOL scores during radiotherapy including the domains of global health status, social functioning, fatigue, nausea and vomiting, pain, insomnia, appetite loss, and constipation. Conclusions and Relevance: Among patients with low-risk NPC, treatment with IMRT alone resulted in 3-year failure-free survival that was not inferior to concurrent chemoradiotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT02633202.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Quimiorradioterapia , Cisplatino , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Infecções por Vírus Epstein-Barr/complicações , Feminino , Herpesvirus Humano 4 , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/etiologia , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/etiologia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Qualidade de Vida , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
11.
Chin Med Sci J ; 37(2): 103-117, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35256042

RESUMO

Objective To explore the association between lipid profiles and left ventricular hypertrophy in a Chinese general population. Methods We conducted a retrospective observational study to investigate the relationship between lipid markers [including triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL-cholesterol, apolipoprotein A-I, apolipoprotein B, lipoprotein[a], and composite lipid profiles] and left ventricular hypertrophy. A total of 309,400 participants of two populations (one from Beijing and another from nationwide) who underwent physical examinations at different health management centers between 2009 and 2018 in China were included in the cross-sectional study. 7,475 participants who had multiple physical examinations and initially did not have left ventricular hypertrophy constituted a longitudinal cohort to analyze the association between lipid markers and the new-onset of left ventricular hypertrophy. Left ventricular hypertrophy was measured by echocardiography and defined as an end-diastolic thickness of the interventricular septum or left ventricle posterior wall > 11 mm. The Logistic regression model was used in the cross-sectional study. Coxmodel and Coxmodel with restricted cubic splines were used in the longitudinal cohort. Results In the cross-sectional study, for participants in the highest tertile of each lipid marker compared to the respective lowest, triglycerides [odds ratio (OR): 1.250, 95%CI: 1.060 to 1.474], HDL-cholesterol (OR: 0.780, 95%CI: 0.662 to 0.918), and lipoprotein(a) (OR: 1.311, 95%CI: 1.115 to 1.541) had an association with left ventricular hypertrophy. In the longitudinal cohort, for participants in the highest tertile of each lipid marker at the baseline compared to the respective lowest, triglycerides [hazard ratio (HR): 3.277, 95%CI: 1.720 to 6.244], HDL-cholesterol (HR: 0.516, 95%CI: 0.283 to 0.940), non-HDL-cholesterol (HR: 2.309, 95%CI: 1.296 to 4.112), apolipoprotein B (HR: 2.244, 95%CI: 1.251 to 4.032) showed an association with new-onset left ventricular hypertrophy. In the Coxmodel with forward stepwise selection, triglycerides were the only lipid markers entered into the final model. Conclusion Lipids levels, especially triglycerides, are associated with left ventricular hypertrophy. Controlling triglycerides level potentiate to be a strategy in harnessing cardiac remodeling but deserve to be further investigated.


Assuntos
Colesterol , Hipertrofia Ventricular Esquerda , Biomarcadores , HDL-Colesterol , Estudos Transversais , Humanos , Hipertrofia Ventricular Esquerda/epidemiologia , Estudos Retrospectivos , Triglicerídeos
12.
Chemosphere ; 287(Pt 1): 131962, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34450369

RESUMO

A fish scale-based porous activated biochar with defined pore size (DPBC) was fabricated by a one-step calcination and activation method. The DPBC possessed an ultrahigh specific surface area of 3370 m2 g-1 and its pore diameter centered at 1.49 nm which fits into the ciprofloxacin (CIP) molecular dimension, making it an ideal adsorbent for CIP adsorption due to the molecular pore-filling effect. The maximum Langmuir monolayer adsorption capacity of DPBC for CIP was higher than 1000 mg g-1 and the equilibrium time was less than 4 h, superior to most adsorbents reported in literature. Thermodynamic analysis indicated the adsorption process was spontaneous and endothermic. Notably, fixed-bed experiments showed an encouraging adsorption performance towards CIP, with a high saturated dynamic adsorption capacity of 880.3 mg g-1. Both Thomas and Yoon-Nelson models predict the fixed-bed column adsorption performance well. Hydrophobic effect, π-π interaction, π-π EDA, cation exchange, hydrogen bonding formation, pore filling effect, electrostatic and cation-π interaction involved in the CIP adsorption on the DPBC.


Assuntos
Ciprofloxacina , Poluentes Químicos da Água , Adsorção , Animais , Carvão Vegetal , Cinética , Poluentes Químicos da Água/análise
13.
Chem Commun (Camb) ; 58(3): 451-454, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34904975

RESUMO

We unprecedentedly report spatially separated CoNx nanodots on carbon nanotubes (CNTs) via a facile formamide condensation reaction. To our knowledge, CoNx-CNTs outperform the activities of current catalysts in peroxymonosulfate activation. CoNx-CNT-oriented radical-free degradation of contaminants shows robust anti-interference capacity toward environmental conditions. Our work will stimulate general interest in designing cost-effective and versatile quantum-/atom-sized catalysts with fully exposed active sites for water purification and beyond.

14.
Chemosphere ; 288(Pt 3): 132634, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34699882

RESUMO

Arsenic is a highly toxic pollutant and exists in inorganic and organic forms in groundwater and industrial wastewater. It is of great importance to reduce the arsenic content to lower levels in the water (e.g., <10 ppb for drinking) in order to minimize risk to humans. In this study, a Fe-Mn-Zr ternary magnetic sorbent was fabricated via precipitation for removal of inorganic and organic arsenate. The synthesis of sorbent was optimized by Taguchi method, which leads to an adsorbent with higher adsorption capacity. The adsorption of As(V) was pH dependent; the optimal removal was achieved at pH 2 and 5 for inorganic and organic As(V), respectively. Contact time of 25 h was sufficient for complete adsorption of both inorganic and organic As(V). The adsorption isotherm study revealed that the adsorbent performed better in sequestration of inorganic As(V) than that of organic As(V); both adsorption followed the Langmuir isotherm with maximum adsorption capacities of 81.3 and 16.98 mg g-1 for inorganic and organic As(V), respectively. The existence of anions in the water had more profound effect on the adsorption of organic As(V) than the inorganic As(V). The co-existing silicate and phosphate ions caused significantly negative impacts on the adsorption of both As(V). Furthermore, the existence of humic acid caused the deterioration of inorganic As(V) removal but showed insignificant impact on the organic As(V) adsorption. The mechanism study demonstrated that ion exchange and complexation played key roles in arsenic removal. This study provides a promising magnetic adsorptive material for simultaneous removal of inorganic and organic As(V).


Assuntos
Arsênio , Poluentes Químicos da Água , Purificação da Água , Adsorção , Arsênio/análise , Humanos , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Água , Poluentes Químicos da Água/análise
15.
Membranes (Basel) ; 11(4)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801696

RESUMO

Electrospun nanofiber with interconnected porous structure has been studied as a promising support layer of polyamide (PA) thin-film composite (TFC) forward osmosis (FO) membrane. However, its rough surface with irregular pores is prone to the formation of a defective PA active layer after interfacial polymerization, which shows high reverse salt leakage in FO desalination. Heat-curing is beneficial for crosslinking and stabilization of the PA layer. In this work, a nanofiber-supported PA TFC membrane was conceived to be cured on a hot water surface with preserved phase interface for potential "defect repair", which could be realized by supplementary interfacial polymerization of residual monomers during heat-curing. The resultant hot-water-curing FO membrane with a more uniform superhydrophilic and highly crosslinked PA layer exhibited much lower reverse salt flux (FO: 0.3 gMH, PRO: 0.8 gMH) than that of oven-curing FO membrane (FO: 2.3 gMH, PRO: 2.2 gMH) and achieved ∼4 times higher separation efficiency. It showed superior stability owing to mitigated reverse salt leakage and osmotic pressure loss, with its water flux decline lower than a quarter that of the oven-curing membrane. This study could provide new insight into the fine-tuning of nanofiber-supported TFC FO membrane for high-quality desalination via a proper selection of heat-curing methods.

16.
Huan Jing Ke Xue ; 42(1): 283-292, 2021 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-33372480

RESUMO

This study attempted to shorten the time wasted at the startup of a complete autotrophic nitrogen removal over nitrite (CANON) process in a tidal flow constructed wetland (TFCW) to achieve higher nitrogen removal rates. Thus, the starting performance and the related microbiological characteristics of different kinds of filter media filling the TFCW were explored at an appropriate drainage rate. The results showed that the physicochemical properties of the filter medium could significantly affect the quantity and activity of the functional microbes (especially ANAMMOX bacteria) enriched in the TFCWs, leading to fluctuations of the starting time and nitrogen transformation rates of the systems filled with five different kinds of filter media. Compared with that of gravel, the quantity and activity of ANAMMOX bacteria in the bed could be enhanced to different degrees as the TFCW was filled with ceramsite, zeolite, broken bricks, and lobster shells. Correspondingly, the starting times of the TFCWs with the CANON process were shortened, and their nitrogen removal performances could also be optimized. When the hydraulic loading rate of the TFCW was 0.96 m3·(m2·d)-1, the initiation of the CANON process could be accomplished successfully in the system filled with lobster shells within 300 cycles, since AOB and ANAMMOX bacteria could become dominant quickly in the packing bed. Moreover, the TN and NH4+-N removal rates could reach up to (88.37±1.19)% and (91.03±0.66)%, respectively, followed by those of broken bricks, zeolite, ceramsite, and gravel.

17.
J Hazard Mater ; 401: 123608, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33113718

RESUMO

Electrospun nanofibrous membranes (ENFMs) have many superior advantages, such as large specific surface area, high porosity, easy modification, good flexibility, and easy separation for recycling, which are consider as excellent adsorbents. In this paper, the research progress in the adsorption of heavy metals in water treatment by ENFMs is reviewed. Three types of ENFMs, including organic polymer ENFMs, organic polymer/inorganic material composite ENFMs and inorganic ENFMs are summarized, and their adsorption capacities for heavy metals in water are compared. The adsorption selectivity and capacity of ENFMs for heavy metals are depended largely on the type and number of functional groups on the surface of membranes, and usually the more the functional groups, the higher the adsorption capacity. The adsorption mechanisms of ENFMs are also mainly determined by the type of functional groups on the membrane. At present, the main challenge is to achieve the mass production of high-quality nanofibers and their actual application in the treatment of heavy metal-containing wastewater. Therefore, more consideration should be focused on the improvement of stability, mechanical strength and reusability of ENFMs. This review may provide an insight for the development of ENFMs-based adsorbents for heavy metals separation and water purification in the future.

18.
Front Psychol ; 11: 1555, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765356

RESUMO

Reaction-time variability is a critical index of sustained attention. However, researchers still lack effective measures to establish the association between neurophysiological activity and this behavioral variability. Here, the present study recorded reaction time (RT) and cortical electroencephalogram (EEG) in healthy subjects when they continuously performed an alternative responding task. The frontal theta activity and reaction-time variability were examined trial by trial using the measures of standard deviation (SD) in the time domain and amplitude of low-frequency fluctuation (ALFF) in the frequency domain. Our results showed that the SD of reaction-time variability did not have any correlation with the SD of trial-by-trial frontal theta activity, and the ALFF of reaction-time variability has a significant correlation with the ALFF of trial-by-trial frontal theta activity in 0.01-0.027 Hz. These results suggested the methodological significance of ALFF in establishing the association between neurophysiological activity and reaction-time variability. Furthermore, these findings also support the low-frequency fluctuation as a potential feature of sustained attention.

19.
EMBO Mol Med ; 12(9): e12050, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32657028

RESUMO

Metabolic reprogramming plays important roles in development and progression of nasopharyngeal carcinoma (NPC), but the underlying mechanism has not been completely defined. In this work, we found INSL5 was elevated in NPC tumor tissue and the plasma of NPC patients. Plasma INSL5 could serve as a novel diagnostic marker for NPC, especially for serum VCA-IgA-negative patients. Moreover, higher plasma INSL5 level was associated with poor disease outcome. Functionally, INSL5 overexpression increased, whereas knockdown of its receptor GPCR142 or inhibition of INSL5 reduced cell proliferation, colony formation, and cell invasion in vitro and tumorigenicity in vivo. Mechanistically, INSL5 enhanced phosphorylation and nuclear translocation of STAT5 and promoted glycolytic gene expression, leading to induced glycolysis in cancer cells. Pharmaceutical inhibition of glycolysis by 2-DG or blockade of INSL5 by a neutralizing antibody reversed INSL5-induced proliferation and invasion, indicating that INSL5 can be a potential therapeutic target in NPC. In conclusion, INSL5 enhances NPC progression by regulating cancer cell metabolic reprogramming and is a potential diagnostic and prognostic marker as well as a therapeutic target for NPC.


Assuntos
Neoplasias Nasofaríngeas , Fator de Transcrição STAT5 , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glicólise , Humanos , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética
20.
Int J Mol Sci ; 21(7)2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276422

RESUMO

Muscle growth and development are important aspects of chicken meat production, but the underlying regulatory mechanisms remain unclear and need further exploration. CRISPR has been used for gene editing to study gene function in mice, but less has been done in chick muscles. To verify whether postnatal gene editing could be achieved in chick muscles and determine the transcriptomic changes, we knocked out Myostatin (MSTN), a potential inhibitor of muscle growth and development, in chicks and performed transcriptome analysis on knock-out (KO) muscles and wild-type (WT) muscles at two post-natal days: 3d (3-day-old) and 14d (14-day-old). Large fragment deletions of MSTN (>5 kb) were achieved in all KO muscles, and the MSTN gene expression was significantly downregulated at 14d. The transcriptomic results indicated the presence of 1339 differentially expressed genes (DEGs) between the 3d KO and 3d WT muscles, as well as 597 DEGs between 14d KO and 14d WT muscles. Many DEGs were found to be related to cell differentiation and proliferation, muscle growth and energy metabolism. This method provides a potential means of postnatal gene editing in chicks, and the results presented here could provide a basis for further investigation of the mechanisms involved in muscle growth and development.


Assuntos
Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Miostatina/genética , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas , Galinhas , Edição de Genes
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