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1.
Plant Cell ; 34(7): 2747-2764, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35385118

RESUMO

Many glycine-rich RNA-binding proteins (GR-RBPs) have critical functions in RNA processing and metabolism. Here, we describe a role for the tomato (Solanum lycopersicum) GR-RBP SlRBP1 in regulating mRNA translation. We found that SlRBP1 knockdown mutants (slrbp1) displayed reduced accumulation of total chlorophyll and impaired chloroplast ultrastructure. These phenotypes were accompanied by deregulation of the levels of numerous key transcripts associated with chloroplast functions in slrbp1. Furthermore, native RNA immunoprecipitation-sequencing (nRIP-seq) recovered 61 SlRBP1-associated RNAs, most of which are involved in photosynthesis. SlRBP1 binding to selected target RNAs was validated by nRIP-qPCR. Intriguingly, the accumulation of proteins encoded by SlRBP1-bound transcripts, but not the mRNAs themselves, was reduced in slrbp1 mutants. Polysome profiling followed by RT-qPCR assays indicated that the polysome occupancy of target RNAs was lower in slrbp1 plants than in wild-type. Furthermore, SlRBP1 interacted with the eukaryotic translation initiation factor SleIF4A2. Silencing of SlRBP1 significantly reduced SleIF4A2 binding to SlRBP1-target RNAs. Taking these observations together, we propose that SlRBP1 binds to and channels RNAs onto the SleIF4A2 translation initiation complex and promotes the translation of its target RNAs to regulate chloroplast functions.


Assuntos
Solanum lycopersicum , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/genética , Fotossíntese/genética , Polirribossomos/metabolismo
2.
Semin Dial ; 37(2): 178-185, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37798864

RESUMO

BACKGROUND: Citrate anticoagulation is an important anticoagulation method in hemodialysis (HD) but cannot completely prevent the occurrence of coagulation in the extracorporeal circulation (ECC) circuit, and the clinical coagulation status can significantly affect the effect of citrate anticoagulation. In this study, the relationships between clinical coagulation status indicators and coagulation in the ECC circuit in HD patients receiving individualized citrate anticoagulant were studied to explore indicators that may predict coagulation in the ECC circuit. METHODS: This study was a single-center, retrospective clinical study, and clinical data and laboratory tests related to the coagulation status of HD patients receiving individualized regional citrate anticoagulation (RCA) were collected. The relationships between indicators commonly used in clinical practice to evaluate clinical coagulation status and coagulation in the ECC circuit were statistically analyzed to find indicators that can predict the occurrence of coagulation in the ECC circuit. RESULTS: The individualized RCA had a good anticoagulation effect, and the actual citrate infusion rate in nearly 80% of the patients was within ±10% of the theoretical infusion rate. The combined diseases or conditions that affect the coagulation status in vivo may increase the incidence of coagulation in the ECC circuit. The clinical D-dimer level is an independent risk factor that affects and can predict coagulation in the ECC circuit, with a cutoff value of 2.03 mg/L, sensitivity of 59%, and specificity of 78%. CONCLUSION: Individualized RCA can meet the needs of most HD treatments. Abnormal coagulation status in HD patients may increase the incidence of coagulation in the ECC circuit during individualized RCA for HD, and the D-dimer level can predict the occurrence of coagulation in the ECC circuit during this treatment.


Assuntos
Ácido Cítrico , Diálise Renal , Humanos , Ácido Cítrico/farmacologia , Ácido Cítrico/uso terapêutico , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Estudos Retrospectivos , Anticoagulantes/uso terapêutico , Citratos/uso terapêutico , Circulação Extracorpórea
3.
Psychol Res ; 86(3): 757-768, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34009467

RESUMO

In complex interactive scenarios, action understanding lies at the heart of social interactions. Nevertheless, the ability to understand action intention may differ among people. The current study distinguished two groups of participants with different social intention-understanding abilities (high and low) based on a perspective-taking task to investigate the influence of social intention on object affordance under conditions of individual and cooperative action intention. In the affordance perception experiment, participants were shown a video with the presenter reaching to grasp an object in different grips and asked to classify objects into kitchen or non-kitchen items by pressing the left- or right-hand button under the two intention conditions. The results showed that the object affordance effects were modulated by the participants' understanding of social intention in the interactive scenarios. Specifically, the object affordance effects were observed only in the high perspective-taking ability group under the condition of cooperative action intention. However, under the condition of individual action intention, object affordance effects were shown in both the high and low perspective-taking ability groups, and the difference between the two groups was not significant. This study suggests that processing of object affordance depends greatly on the contextual correspondence of perception and action and that the understanding of cooperative action intention can affect the activation of object affordance.


Assuntos
Intenção , Desempenho Psicomotor , Mãos/fisiologia , Força da Mão , Humanos , Desempenho Psicomotor/fisiologia
4.
Opt Express ; 29(6): 8698-8709, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820312

RESUMO

In this investigation, we propose a strip segmentation phase (SSP) method for a spatial light modulator (SLM) to generate independent multifocal spots when the beam passes through a high numerical aperture (NA) lens. With the SSP method, multifocal spots can be generated with each spot independently, flexibly and uniformly distributed. The performance of the SSP method is first validated with numerical simulation. Then, by applying the modulation method with SLM and importing the beams into an inverted fluorescence microscopy system with a high-NA lens, the spot distribution and their shapes can be observed by fluorescent image. The fluorescent image exhibits high uniformity and high consistency with the aforementioned numerical simulations. Finally, we dynamically load a series of phase maps on SLM to realize continuous and independent spot movement in a multifocal array. By laser direct writing on photoresist, a complex NWU-shape structure can be realized flexibly with multi-task fabrication capability. The SSP method can significantly improve the efficiency and flexibility of laser direct writing. It is also compatible with most recent techniques, e.g., multiphoton absorption, stimulated emission depletion and photo-induced depolymerization etc., to realize parallel super-resolution imaging and fabrications.

5.
Bull Environ Contam Toxicol ; 102(5): 721-729, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30756128

RESUMO

Mercury contamination in soil and water has become a major concern to environmental quality and human health. Among the existing remediation technologies for mercury pollution control, sorption via iron-based materials has received wide attention as they are environmental friendly and economic, and their reactivity is high and controllable through modulating the morphology and surface properties of particulate materials. This paper aimed to provide a comprehensive overview on environmental application of a variety of iron-based sorbents, namely, zero valent iron, iron oxides, and iron sulfides, for mercury remediation. Techniques to improve the stability of these materials while enhancing mercury sequestration, such as nano-scale size control, surface functionalization, and mechanical support, were summarized. Mechanisms and factors affecting the interaction between mercury and iron-based materials were also discussed. Current knowledge gaps and future research needs are identified to facilitate a better understanding of molecular-level reaction mechanisms between iron-based materials and mercury and the long-term stability of the immobilized mercury.


Assuntos
Recuperação e Remediação Ambiental/métodos , Ferro/química , Mercúrio/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Solo
6.
Conscious Cogn ; 57: 84-93, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29190489

RESUMO

The present study investigated the roles of bottom-up mask-triggered inhibition and top-down inhibition in semantic categorization using the single negative priming (NP) paradigm. The masking (bottom-up) and ignore instructions (top-down, i.e., instructing participants to ignore the primes) were manipulated in Experiments 1-3 and Experiment 4, respectively. No priming was observed when only the masking was manipulated (Experiments 2 and 3), but NP was observed when a possible top-down ignore strategy (Experiment 1) or an ignore instruction (Experiment 4) was added. The results indicate that bottom-up mask-triggered inhibition cannot elicit semantic single NP by itself. However, top-down inhibition from an ignore instruction or ignore strategy is critical for triggering reliable semantic single NP. The findings suggest that semantic single NP originates from a push-pull mechanism by facilitating responses to unrelated trials and inhibiting responses to related trials. The experimental evidence also suggests that unconscious processes can be modulated by top-down control.


Assuntos
Função Executiva/fisiologia , Inibição Psicológica , Reconhecimento Visual de Modelos/fisiologia , Mascaramento Perceptivo/fisiologia , Semântica , Adolescente , Adulto , Estado de Consciência/fisiologia , Feminino , Humanos , Masculino , Leitura , Adulto Jovem
7.
J Environ Sci (China) ; 67: 378-386, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29778171

RESUMO

The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate (AD) harvested from a wastewater treatment plant. The combination of zero valent iron (ZVI, 0-4.0g/g total solids (TS)) and hydrogen peroxide (HP, 0-90mg/g TS) under pH3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18mg HP/g TS and 2.0g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP+ZVI conditioning.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Esgotos , Águas Residuárias/química
8.
Environ Sci Technol ; 48(7): 3986-94, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24568693

RESUMO

Iron sulfide (FeS) nanoparticles were prepared with sodium carboxymethyl cellulose (CMC) as a stabilizer, and tested for enhanced removal of aqueous mercury (Hg(2+)). CMC at ≥0.03 wt % fully stabilized 0.5 g/L of FeS (i.e., CMC-to-FeS molar ratio ≥0.0006). FTIR spectra suggested that CMC molecules were attached to the nanoparticles through bidentate bridging and hydrogen bonding. Increasing the CMC-to-FeS molar ratio from 0 to 0.0006 enhanced mercury sorption capacity by 20%; yet, increasing the ratio from 0.0010 to 0.0025 diminished the sorption by 14%. FTIR and XRD analyses suggested that precipitation (formation of cinnabar and metacinnabar), ion exchange (formation of Hg0.89Fe0.11S), and surface complexation were important mechanisms for mercury removal. A pseudo-second-order kinetic model was able to interpret the sorption kinetics, whereas a dual-mode isotherm model was proposed to simulate the isotherms, which considers precipitation and adsorption. High mercury uptake was observed over the pH range of 6.5-10.5, whereas significant capacity loss was observed at pH < 6. High concentrations of Cl(-) (>106 mg/L) and organic matter (5 mg/L as TOC) modestly inhibited mercury uptake. The immobilized mercury remained stable when preserved for 2.5 years at pH above neutral.


Assuntos
Carboximetilcelulose Sódica/química , Ferro/química , Mercúrio/química , Nanopartículas/química , Sulfetos/química , Água/química , Adsorção , Cloretos/química , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Cinética , Pós , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo
9.
Environ Sci Technol ; 48(24): 14392-9, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25420231

RESUMO

This work explored the formation mechanism of marine oil snow (MOS) and the associated transport of oil hydrocarbons in the presence of a stereotype oil dispersant, Corexit EC9500A. Roller table experiments were carried out to simulate natural marine processes that lead to formation of marine snow. We found that both oil and the dispersant greatly promoted the formation of MOS, and MOS flocs as large as 1.6-2.1 mm (mean diameter) were developed within 3-6 days. Natural suspended solids and indigenous microorganisms play critical roles in the MOS formation. The addition of oil and the dispersant greatly enhanced the bacterial growth and extracellular polymeric substance (EPS) content, resulting in increased flocculation and formation of MOS. The dispersant not only enhanced dissolution of n-alkanes (C9-C40) from oil slicks into the aqueous phase, but facilitated sorption of more oil components onto MOS. The incorporation of oil droplets in MOS resulted in a two-way (rising and sinking) transport of the MOS particles. More lower-molecular-weight (LMW) n-alkanes (C9-C18) were partitioned in MOS than in the aqueous phase in the presence of the dispersant. The information can aid in our understanding of dispersant effects on MOS formation and oil transport following an oil spill event.


Assuntos
Hidrocarbonetos/química , Lipídeos/química , Poluição por Petróleo , Petróleo , Poluentes Químicos da Água/química , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Biopolímeros/química , Biopolímeros/metabolismo , Floculação
10.
Int Urol Nephrol ; 56(1): 295-302, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37347360

RESUMO

OBJECTIVE: To evaluate the safety and effectiveness of an individualized regional citrate anticoagulation (RCA) protocol for hemodialysis. METHODS: In this single-center, retrospective study, blood coagulation in the extracorporeal circulation, adverse reactions, in vivo ionized calcium (iCa2+) concentrations, and the infusion dose of citrate during RCA in hemodialysis were observed in 98 patients from February 2021 to March 2022. RESULTS: A total of 98 patients underwent RCA during hemodialysis 362 times, and blood coagulation occurred in the extracorporeal circulation 29 times. Among the 29 cases of coagulation, most of the patients exhibited hypercoagulability, and among approximately 80% of the treatments, the deviation between the actual infusion rate of citrate in the extracorporeal circulation and the theoretical value was ± 10%. After hemodialysis, pH values and bicarbonate ion (HCO3-) levels were clearly improved, and online conductivity monitoring (OCM) values and blood coagulation scores in the extracorporeal circulation were identical to those measured in similar studies. CONCLUSION: An individualized RCA protocol for hemodialysis is safe, effective, simple, and inexpensive and can meet the needs of individualized treatment; therefore, its application is worthy of promotion.


Assuntos
Anticoagulantes , Ácido Cítrico , Humanos , Ácido Cítrico/uso terapêutico , Estudos Retrospectivos , Anticoagulantes/efeitos adversos , Citratos/uso terapêutico , Coagulação Sanguínea , Diálise Renal/métodos , Cálcio
11.
Sci Total Environ ; 944: 173928, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38871308

RESUMO

Mercury (Hg) pollution in soil has grown into a severe environmental issue. Effective in situ immobilization techniques are crucially demanded. In this study, we explored the application of carboxymethyl cellulose stabilized iron sulfide nanoparticles (CMC-FeS) for in situ immobilization of Hg in soil. CMC-FeS (a CMC-to-FeS molar ratio of 0.0004) was prepared via the reaction between FeSO4 and Na2S using CMC as a stabilizer. Remedying the Hg-polluted soil using 0.03 % CMC-FeS via batch experiments effectively reduced the acid leachable Hg by 97.5 % upon equilibrium after 71 days. Column elution tests demonstrated that the addition of CMC-FeS decreased the peak Hg concentration by 89.9 % and the total Hg mass eluted by 94.9 % after 523 pore volumes. CMC-FeS immobilized Hg in soil via chemical precipitation, ion exchange, and surface complexation. After the CMC-FeS treatment, Hg was transformed from more available exchangeable, carbonate-bound, and organic material-bound forms into the less available residual fraction, reducing the environmental risk of soil Hg from medium to low. The application of CMC-FeS boosted the soil enzyme activities and enhanced the soil bacterial diversity whereas decreased the production of methylmercury. CMC-FeS also facilitated long-term immobilization of Hg in soil. The acid leachable Hg and relative Hg bioaccessibility was decreased. Lift cycle assessment indicated that the preparation and application of CMC-FeS for in situ Hg remediation in soil met green chemistry principles. The present study confirms that CMC-FeS can be applied as an efficient and "green" amending agent for long-term Hg immobilization in soil/sediment.

12.
Int J Surg ; 110(6): 3839-3847, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489547

RESUMO

BACKGROUND: Deep learning (DL)-assisted detection and segmentation of intracranial hemorrhage stroke in noncontrast computed tomography (NCCT) scans are well-established, but evidence on this topic is lacking. MATERIALS AND METHODS: PubMed and Embase databases were searched from their inception to November 2023 to identify related studies. The primary outcomes included sensitivity, specificity, and the Dice Similarity Coefficient (DSC); while the secondary outcomes were positive predictive value (PPV), negative predictive value (NPV), precision, area under the receiver operating characteristic curve (AUROC), processing time, and volume of bleeding. Random-effect model and bivariate model were used to pooled independent effect size and diagnostic meta-analysis data, respectively. RESULTS: A total of 36 original studies were included in this meta-analysis. Pooled results indicated that DL technologies have a comparable performance in intracranial hemorrhage detection and segmentation with high values of sensitivity (0.89, 95% CI: 0.88-0.90), specificity (0.91, 95% CI: 0.89-0.93), AUROC (0.94, 95% CI: 0.93-0.95), PPV (0.92, 95% CI: 0.91-0.93), NPV (0.94, 95% CI: 0.91-0.96), precision (0.83, 95% CI: 0.77-0.90), DSC (0.84, 95% CI: 0.82-0.87). There is no significant difference between manual labeling and DL technologies in hemorrhage quantification (MD 0.08, 95% CI: -5.45-5.60, P =0.98), but the latter takes less process time than manual labeling (WMD 2.26, 95% CI: 1.96-2.56, P =0.001). CONCLUSION: This systematic review has identified a range of DL algorithms that the performance was comparable to experienced clinicians in hemorrhage lesions identification, segmentation, and quantification but with greater efficiency and reduced cost. It is highly emphasized that multicenter randomized controlled clinical trials will be needed to validate the performance of these tools in the future, paving the way for fast and efficient decision-making during clinical procedure in patients with acute hemorrhagic stroke.


Assuntos
Aprendizado Profundo , Hemorragias Intracranianas , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Sensibilidade e Especificidade
13.
Nanomaterials (Basel) ; 14(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38786793

RESUMO

In order to prepare biomass-derived carbon materials with high specific capacitance at a low activation temperature (≤700 °C), nanoporous carbon materials were prepared from zanthoxylum bungeanum peels and seeds via the pyrolysis and KOH-activation processes. The results show that the optimal activation temperatures are 700 °C and 600 °C for peels and seeds. Benefiting from the hierarchical pore structure (micropores, mesopores, and macropores), the abundant heteroatoms (N, S, and O) containing functional groups, and plentiful electrochemical active sites, the PAC-700 and SAC-600 derive the large capacities of ~211.0 and ~219.7 F g-1 at 1.0 A g-1 in 6 M KOH within the three-electrode configuration. Furthermore, the symmetrical supercapacitors display a high energy density of 22.9 and 22.4 Wh kg-1 at 7500 W kg-1 assembled with PAC-700 and SAC-600, along with exceptional capacitance retention of 99.1% and 93.4% over 10,000 cycles at 1.0 A g-1. More significantly, the contribution here will stimulate the extensive development of low-temperature activation processes and nanoporous carbon materials for electrochemical energy storage and beyond.

14.
J Ind Microbiol Biotechnol ; 40(12): 1433-41, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24052228

RESUMO

A cDNA gene (AufaeA), which encodes a mature polypeptide of the type-A feruloyl esterase from Aspergillus usamii E001 (abbreviated to AuFaeA), was cloned and heterologously expressed in Pichia pastoris GS115. One transformant, labeled as P. pastoris GSFaeA4-8, expressing the highest recombinant AuFaeA (reAuFaeA) activity of 10.76 U/ml was selected by the flask expression test. The expressed reAuFaeA was purified to homogeneity with an apparent molecular weight of 36.0 kDa by SDS-PAGE analysis, and characterized using the model substrate of methyl ferulate (MFA). The purified reAuFaeA was optimally active at pH 5.0 and 45 °C, and highly stable at pH 4.0-6.5 and 45 °C or below. Its activity was not significantly affected by metal ions tested and EDTA. The K m and V max of reAuFaeA towards MFA were 4.64 mM and 115.5 U/mg, respectively. High-performance liquid chromatography analysis showed that only 9.7 % of total alkali-extractable ferulic acid (FA) was released from destarched wheat bran by reAuFaeA alone. The released FA increased to 36.5 % when reAuFaeA was used together with a recombinant Aspergillus usamii GH family 11 xylanase A, indicating a synergistic interaction between them.


Assuntos
Aspergillus/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Ácidos Cumáricos/metabolismo , Fibras na Dieta/metabolismo , Proteínas Fúngicas/metabolismo , Sequência de Aminoácidos , Aspergillus/genética , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/isolamento & purificação , Clonagem Molecular , Biologia Computacional , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida , Endo-1,4-beta-Xilanases/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Dados de Sequência Molecular , Peso Molecular , Pichia/enzimologia , Pichia/genética , Reação em Cadeia da Polimerase , Conformação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos
15.
Int J Artif Organs ; 46(6): 329-336, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37278534

RESUMO

OBJECTIVE: To investigate non-anticoagulant factors that affect blood coagulation in the extracorporeal circulation (ECC) circuit of regional citrate anticoagulation (RCA) protocol for hemodialysis (HD). METHOD: The clinical characteristics of patients undergoing an individualized RCA protocol for HD between February 2021 and March 2022 were collected; Coagulation scores, pressures in various parts of the ECC circuit, the incidence of coagulation, and citrate concentrations in the ECC circuit during treatment were determined, and non-anticoagulant factors affecting coagulation in the ECC circuit were analyzed. RESULT: The lowest clotting rate was 2.8% in patients with arteriovenous fistula in various vascular access. Patients on Fresenius dialysis had a lower rate of clotting in the cardiopulmonary bypass line than patients on other brands of dialyzer. Low-throughput dialyzers are less likely to clot than high-throughput dialyzers. There are significant differences in the incidence of coagulation among different nurses during citrate anticoagulant hemodialysis. CONCLUSION: In the process of citrate anticoagulant hemodialysis, non-anticoagulant factors such as coagulation status, vascular access, dialyzer selection, and operator quality will affect the anticoagulant effect.


Assuntos
Anticoagulantes , Ácido Cítrico , Humanos , Ácido Cítrico/farmacologia , Ácido Cítrico/uso terapêutico , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Estudos Retrospectivos , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Coagulação Sanguínea , Citratos/farmacologia , Citratos/uso terapêutico , Circulação Extracorpórea
16.
Chemosphere ; 337: 139207, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37364639

RESUMO

Atrazine is a toxic endocrine disruptor. Biological treatment methods are considered to be effective. In the present study, a modified version of the algae-bacteria consortia (ABC) was established and a control was simultaneously set up to investigate the synergistic relationship between bacteria and algae and the mechanism by which atrazine is metabolized by those microorganisms. The total nitrogen (TN) removal efficiency of the ABC reached 89.24% and the atrazine concentration was reduced to below the level recommended by the Environment Protection Agency (EPA) regulatory standards within 25 days. The protein signal released from the extracellular polymeric substances (EPS) secreted by the microorganisms triggered the resistance mechanism of the algae, and the conversion of humic acid to fulvic acid and electron transfer constituted the synergistic mechanism between the bacteria and algae. The mechanism by which atrazine is metabolized by the ABC mainly consists of hydrogen bonding, H-pi interactions, and cation exchange with atzA for hydrolysis, followed by a reaction with atzC for decomposition to non-toxic cyanuric acid. Proteobacteria was the dominant phylum for bacterial community evolution under atrazine stress, and the analysis revealed that the removal of atrazine within the ABC was mainly dependent on the proportion of Proteobacteria and the expression of degradation genes (p < 0.01). EPS played a major role in the removal of atrazine within the single bacteria group (p < 0.01).


Assuntos
Atrazina , Atrazina/análise , Águas Residuárias , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental
17.
Micromachines (Basel) ; 14(3)2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36985086

RESUMO

Flow cytometry is a widespread and powerful technique whose resolution is determined by its capacity to accurately distinguish fluorescently positive populations from negative ones. However, most informative results are discarded while performing the measurements of conventional flow cytometry, e.g., the cell size, shape, morphology, and distribution or location of labeled exosomes within the unpurified biological samples. Herein, we propose a novel approach using an anti-diffraction light sheet with anisotroic feature to excite fluorescent tags. Constituted by an anti-diffraction Bessel-Gaussian beam array, the light sheet is 12 µm wide, 12 µm high, and has a thickness of ~0.8 µm. The intensity profile of the excited fluorescent signal can, therefore, reflect the size and allow samples in the range from O (100 nm) to 10 µm (e.g., blood cells) to be transported via hydrodynamic focusing in a microfluidic chip. The sampling rate is 500 kHz, which provides a capability of high throughput without sacrificing the spatial resolution. Consequently, the proposed anti-diffraction light sheet flow cytometry (ADLSFC) can obtain more informative results than the conventional methodologies, and is able to provide multiple characteristics (e.g., the size and distribution of fluorescent signal) helping to distinguish the target samples from the complex backgrounds.

18.
Polymers (Basel) ; 15(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904376

RESUMO

Photothermal slippery surface has broad applications in many research fields for noncontacting, loss-free, and flexible droplet manipulation capability. In this work, with specific morphologic parameters and modified base materials doped by Fe3O4, a high-durability photothermal slippery surface (HD-PTSS) was proposed and implemented based on ultraviolet (UV) lithography to achieve repeatability of more than 600 cycles. The instantaneous response time and transport speed of HD-PTSS were related to near-infrared ray (NIR) powers and droplet volume. Meanwhile, the durability was closely related to the morphology of HD-PTSS, which impacts the recovering of a lubricant layer. The droplet manipulation mechanism of HD-PTSS was discussed in depth, and the Marangoni effect was found to be the key factor for the durability of HD-PTSS.

19.
Nanotechnology ; 23(29): 294007, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22743738

RESUMO

Mercury (Hg) is one of the most pervasive and bio-accumulative metals in the environment. Yet, effective in situ remediation technologies have been lacking. This study investigated the effectiveness of a class of soil-deliverable FeS nanoparticles for in situ immobilization of Hg in two field-contaminated soils from a New Jersey site and one sediment from an Alabama site. The nanoparticles were prepared using sodium carboxymethyl cellulose (CMC) as a stabilizer. Transmission electron microscopy measurements revealed a particle size of 34.3 ± 8.3 nm (standard deviation), whereas dynamic light scattering gave a hydrodynamic diameter of 222.5 ± 3.2 nm. Batch tests showed that at an FeS-to-Hg molar ratio of 28:1-118:1, the nanoparticles reduced water-leachable Hg by 79%-96% and the TCLP (toxicity characteristic leaching procedure) based leachability by 26%-96%. Column breakthrough tests indicated that the nanoparticles were deliverable in the sediment/soil columns under moderate injection pressure. However, once the external pressure was removed, the delivered nanoparticles remained virtually mobile under typical groundwater flow conditions. When the Hg-contaminated soil and sediment were treated with 52-95 pore volumes of a 500 mg l(-1) FeS nanoparticle suspension, water-leachable Hg was reduced by 90%-93% and TCLP-leachable Hg was reduced by 65%-91%. The results warrant further field demonstration of this promising in situ remediation technology.


Assuntos
Carboximetilcelulose Sódica/química , Recuperação e Remediação Ambiental/métodos , Compostos de Ferro/química , Mercúrio/isolamento & purificação , Nanopartículas/química , Poluentes do Solo/isolamento & purificação , Sedimentos Geológicos/análise , Nanopartículas/ultraestrutura , Solo/análise , Sulfetos/química
20.
Water Res ; 208: 117884, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837810

RESUMO

Nanoplastics (NPs) pollution of aquatic systems is becoming an emerging environmental issue due to their stable structure, high mobility, and easy interactions with ambient contaminants. Effective removal technologies are urgently needed to mitigate their toxic effects. In this study, we systematically investigated the removal effectiveness and mechanisms of a commonly detected nanoplastics, carboxyl-modified polystyrene (PS-COOH) via coagulation and sedimentation processes using aluminum chloride (AlCl3) as a coagulant. PS-COOH appeared as clearly defined and discrete spherical nanoparticles in water with a hydrodynamic diameter of 50 nm. The addition of 10 mg/L AlCl3 compressed and even destroyed the negatively charged PS-COOH surface layer, decreased the energy barrier, and efficiently removed 96.6% of 50 mg/L PS-COOH. The dominant removal mechanisms included electrostatic adsorption and intermolecular interactions. Increasing the pH from 3.5 to 8.5 sharply enhanced the PS-COOH removal, whereas significant loss was observed at pH 10.0. High temperature (23 °C) favored the removal of PS-COOH compared to lower temperature (4 °C). High PS-COOH removal efficiency was observed over the salinity range of 0 - 35‰. The presence of positively charged Al2O3 did not affect the PS-COOH removal, while negatively charged SiO2 reduced the PS-COOH removal from 96.6% to 93.2%. Moreover, the coagulation and sedimentation process efficiently removed 90.2% of 50 mg/L PS-COOH in real surface water even though it was rich in inorganic ions and total organic carbon. The fast and efficient capture of PS-COOH by AlCl3 via a simple coagulation and sedimentation process provides a new insight for the treatment of NPs from aqueous environment.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Cloreto de Alumínio , Microplásticos , Poliestirenos , Dióxido de Silício , Água , Poluentes Químicos da Água/análise
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