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The microtubule-associated protein tau participates in neurotransmission regulation via its interaction with synaptic vesicles (SVs). The precise nature and mechanics of tau's engagement with SVs, especially regarding alterations in vesicle dynamics, remain a matter of discussion. We report an electrochemical method using a synapse-mimicking nanopipette to monitor vesicle dynamics induced by tau. A model vesicle of ~30â nm is confined within a lipid-modified nanopipette orifice with a comparable diameter to mimic the synaptic lipid environment. Both tau and phosphorylated tau (p-tau) present two-state dynamic behavior in this biomimetic system, showing typical ionic current oscillation, induced by lipid-tau interaction. The results indicate that p-tau has a stronger affinity to the lipid vesicles in the confined environment, blocking the vesicle movement to a higher degree. Taken together, this method bridges a gap for sensing synaptic vesicle dynamics in a confined lipid environment, mimicking vesicle movement near the synaptic membrane. These findings contribute to understanding how different types of tau protein regulate synaptic vesicle motility and to underlying its functional and pathological behaviours in disease.
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Cell migration is known to be a fundamental biological process, playing an essential role in development, homeostasis, and diseases. This paper introduces a cell tracking algorithm named HFM-Tracker (Hybrid Feature Matching Tracker) that automatically identifies cell migration behaviours in consecutive images. It combines Contour Attention (CA) and Adaptive Confusion Matrix (ACM) modules to accurately capture cell contours in each image and track the dynamic behaviors of migrating cells in the field of view. Cells are firstly located and identified via the CA module-based cell detection network, and then associated and tracked via a cell tracking algorithm employing a hybrid feature-matching strategy. This proposed HFM-Tracker exhibits superiorities in cell detection and tracking, achieving 75% in MOTA (Multiple Object Tracking Accuracy) and 65% in IDF1 (ID F1 score). It provides quantitative analysis of the cell morphology and migration features, which could further help in understanding the complicated and diverse cell migration processes.
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Algoritmos , Movimento Celular , Rastreamento de Células , Rastreamento de Células/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodosRESUMO
Electrochemical carbon dioxide reduction reaction using sustainable energy is a promising approach of synthesizing chemicals and fuels, yet is highly energy intensive. The oxygen evolution reaction is particularly problematic, which is kinetically sluggish and causes anodic carbon loss. In this context, we couple CO2 electrolysis with hydrogen oxidation reaction in a single electrochemical cell. A Ni(OH)2/NiOOH mediator is used to fully suppress the anodic carbon loss and hydrogen oxidation catalyst poisoning by migrated reaction products. This cell is highly flexible in producing either gaseous (CO) or soluble (formate) products with high selectivity (up to 95.3%) and stability (>100 h) at voltages below 0.9 V (50 mA cm-2). Importantly, thanks to the "transferred" oxygen evolution reaction to a water electrolyzer with thermodynamically and kinetically favored reaction conditions, the total polarization loss and energy consumption of our H2-integrated CO2 reduction reaction, including those for hydrogen generation, are reduced up to 22% and 42%, respectively. This work demonstrates the opportunity of combining CO2 electrolysis with the hydrogen economy, paving the way to the possible integration of various emerging energy conversion and storage approaches for improved energy/cost effectiveness.
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OBJECTIVE: The intestine is responsible for approximately one-third of uric acid (UA) excretion. The effect of commensal Enterococcus faecalis (E. faecalis), one of the most colonized bacteria in the gut, on UA excretion in the intestine remains to be investigated. The aim of this study was to evaluate the effect of commensal E. faecalis on UA metabolism and gut microbiota. METHODS: The 16S rRNA gene sequencing was used to examine the species of Enterococcus in mouse fecal content. E. faecalis strain was isolated from mouse feces and identified to be E. faecalis W5. The hyperuricemia (HUA) animal model was established with yeast-rich forage and 250 mg·kg-1 ·day-1 potassium oxonate. Oral administration of E. faecalis W5 was given for 20 days, serving as the Efa group. RESULTS: Disrupted intestinal barrier, activated proinflammatory response and low UA excretion in the intestine were found in HUA mice. After E. faecalis W5 treatment, the gut barrier was restored and serum UA level was decreased. Additionally, fecal and intestinal UA levels were elevated, intestinal urate transporter ABCG2 and purine metabolism were upregulated. Moreover, short-chain fatty acid levels were increased, and intestinal inflammation was ameliorated. CONCLUSIONS: Commensal E. faecalis W5 ameliorated HUA through reversing the impaired gut barrier, promoting intestinal UA secretion by regulating ABCG2 expression, and decreasing intestinal UA synthesis by regulating purine metabolism. The results may provide the potential for developing treatments for HUA through the intestine.
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Microbioma Gastrointestinal , Hiperuricemia , Camundongos , Animais , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Enterococcus faecalis , RNA Ribossômico 16S , PurinasRESUMO
To compare the pancreatic proteomics and autophagy between Rehmanniae Radix-and Rehmanniae Radix Praeparata-treated mice with type 2 diabetes mellitus(T2DM). The T2DM mouse model was established by high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days). The mice were then randomly assigned into a control group, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) catalpol groups, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) 5-hydroxymethyl furfuraldehyde(5-HMF) groups, and a metformin(250 mg·kg~(-1)) group. In addition, a normal group was also set and each group included 8 mice. The pancreas was collected after four weeks of administration and proteomics tools were employed to study the effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on protein expression in the pancreas of T2DM mice. The expression levels of proteins involved in autophagy, inflammation, and oxidative stress response in the pancreatic tissues of T2DM mice were determined by western blotting, immunohistochemical assay, and transmission electron microscopy. The results showed that the differential proteins between the model group and Rehmanniae Radix/Rehmanniae Radix Prae-parata group were enriched in 7 KEGG pathways, such as autophagy-animal, which indicated that the 7 pathways may be associated with T2DM. Compared with the control group, drug administration significantly up-regulated the expression levels of beclin1 and phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR and down-regulated those of the inflammation indicators, Toll-like receptor-4(TLR4) and Nod-like receptor protein 3(NLRP3), in the pancreas of T2DM mice, and Rehmanniae Radix showed better performance. In addition, the expression levels of inducible nitric oxide synthase(iNOS), nuclear factor erythroid 2-related factor 2(Nrf2), and heine oxygenase-1(HO-1) in the pancreas of T2DM mice were down-regulated after drug administration, and Rehmanniae Radix Praeparata demonstrated better performance. The results indicate that both Rehmanniae Radix and Rehmanniae Radix Praeparata can alleviate the inflammatory symptoms, reduce oxidative stress response, and increase the autophagy level in the pancreas of T2DM mice, while they exert the effect on different autophagy pathways.
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Diabetes Mellitus Tipo 2 , Camundongos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Estreptozocina/farmacologia , Dieta Hiperlipídica/efeitos adversos , Proteômica , Inflamação , Serina-Treonina Quinases TOR , Autofagia , MamíferosRESUMO
N-doped carbons (NCs) have excellent electrocatalytic performance in oxygen reduction reaction, particularly in alkaline conditions, showing great promise of replacing commercial Pt/C catalysts in fuel cells and metal-air batteries. However, NCs are vulnerable when biased at high potentials, which suffer from denitrogenation and carbon corrosion. Such material degradation drastically undermines the activity, yet its dynamic evolution in response to the applied potentials is challenging to examine experimentally. In this work, we used differential electrochemical mass spectroscopy coupled with an optimized cell and observed the dynamic behaviors of NCs under operando conditions in KOH electrolyte. The corrosion of carbon occurred at ca. 1.2 V vs RHE, which was >0.3 V below the measured onset potential of water oxidation. Denitrogenation proceeded in parallel with carbon corrosion, releasing both NO and NO2. Combined with the ex situ characterizations and density-functional theory calculations, we identified that the pyridinic nitrogen moieties were particularly in peril. Three denitrogenation pathways were also proposed. Finally, we demonstrated that transferring the oxidation reaction sites to the well-deposited metal hydroxide with optimized loading was effective in suppressing the N leaching. This work showed the dynamic evolution of NC under potential bias and might cast light on understanding and mitigating NC deactivation for practical applications.
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Alkaline water electrolysis (AWE) is among the most developed technologies for green hydrogen generation. Despite the tremendous achievements in boosting the catalytic activity of the electrode, the operating current density of modern water electrolyzers is yet much lower than the emerging approaches such as the proton-exchange membrane water electrolysis (PEMWE). One of the dominant hindering factors is the high overpotentials induced by the gas bubbles. Herein, the bubble dynamics via creating the superaerophobic electrode assembly is optimized. The patterned Co-Ni phosphide/spinel oxide heterostructure shows complete wetting of water droplet with fast spreading time (≈300 ms) whereas complete underwater bubble repelling with 180° contact angle is achieved. Besides, the current collector/electrode interface is also modified by coating with aerophobic hydroxide on Ti current collector. Thus, in the zero-gap water electrolyzer test, a current density of 3.5 A cm-2 is obtained at 2.25 V and 85 °C in 6 m KOH, which is comparable with the state-of-the-art PEMWE using Pt-group metal catalyst. No major performance degradation or materials deterioration is observed after 330 h test. This approach reveals the importance of bubble management in modern AWE, offering a promising solution toward high-rate water electrolysis.
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The precise manipulation of single cells plays a fundamental role for single cell measurement, which is crucial for understanding the diverse cellular mechanisms. Unusual single cell behavior could thus be identified by integrating with advanced analytical methods such as single cell omics, unraveling the intrinsic cellular heterogeneity hidden in ensemble measurements. Herein, this technical note reports a nanopipet-based versatile method for manipulation of an ultrasmall volume of liquid, which further enables the precise manipulation of single cells. Femtoliter volumes of cytoplasm were extracted from single living cells and analyzed by time-of-flight secondary ion mass spectrometry. Moreover, several kinds of exogenous components were injected simultaneously into a cell, offering a delicate tool for multi-imaging in single living cells.
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Análise de Célula Única , Espectrometria de Massa de Íon Secundário , Análise de Célula Única/instrumentaçãoRESUMO
This study investigated the differential mechanisms of Rehmanniae Radix and Rehmanniae Radix Praeparata in improving diabetes in mice through AMPK-mediated NF-κB/NLRP3 signaling pathway. The diabetic mouse model was established with high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days), after which the mice were randomly divided into model group, low-dose(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-dose(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, catalpol group(250 mg·kg~(-1)), 5-hydroxymethylfurfural(5-HMF) group(250 mg·kg~(-1)), metformin group(250 mg·kg~(-1)), with the normal group also set. The organ indexes of heart,liver, spleen, lung, kidney and pancreas were calculated after four weeks of administration. The pathological changes and fibrosis of pancreas, kidney and liver in mice were observed by hematoxylin-eosin(HE) staining and Masson staining. Western blot was used to determine the expression levels of Toll-like receptor-4(TLR4), nuclear factor-κB(NF-κB), Nod-like receptor protein 3(NLRP3),interleukin-1ß(IL-1ß), adenosine monophosphate-activated protein kinase(AMPK), phosphorylated AMPK(p-AMPK) in the pancreas, kidney and liver of mice. Compared with the model group, the administration groups witnessed significant decrease in the liver,spleen, kidney, pancreas and fat indexes of diabetic mice, and there was no significant difference in heart and lung indexes. The pathological states and fibrosis of pancreatic, kidney and liver tissues were significantly improved after administration. Additionally, the expression levels of TLR4, NF-κB and NLRP3 in pancreas, kidney and liver of diabetic mice were significantly lowered. The expression levels of p-AMPK/AMPK were enhanced significantly in kidney and liver of mice in Rehmanniae Radix group while in pancreas, kidney and liver in Rehmanniae Radix Praeparata group. This suggests that Rehmanniae Radix and Rehmanniae Radix Praeparata differ in the mechanism of regulating energy metabolism of multiple organs and thereby exerting anti-inflammatory effects to alleviate symptoms of diabetic mice.
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Diabetes Mellitus Experimental , NF-kappa B , Proteínas Quinases Ativadas por AMP/genética , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Extratos Vegetais , Rehmannia , Transdução de Sinais , EstreptozocinaRESUMO
Electrocatalysis is indispensable to various emerging energy conversion and storage devices such as fuel cells and water electrolyzers. Owing to their unique physicochemical properties, perovskite oxide materials are one of the most promising water oxidation (OER) catalysts solely comprising earth-abundant elements. Nonetheless, many perovskite oxide catalysts suffer from a number of inherent problems such as the A-site cation segregation on the surface, coarse particles due to agglomeration/sintering, and surface decomposition during catalytic reactions. Besides, the catalytic activity is often incomparable with those of the state-of-the-art catalysts. In this work, we developed a proton-assisted approach to mitigate these common challenges. The protonation via the interaction of oxygen vacancies and water molecules induced the formation of protonic defects and the lattice expansion of the perovskite, leading to the fracture of big particles to yield small nanoparticles. This hydration in an acidic solution also selectively removed the A-site cation segregates and generated a spinel/perovskite heterostructure on the surface. We verified this approach using three typical perovskite OER catalysts including Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), La0.6Sr0.4Co0.8Fe0.2O3 (LSCF), and La0.75Sr0.25MnO3 (LSM). The processed catalysts showed much improved activity while maintaining their excellent stability, surpassing most of today's OER catalysts based on complex oxides.
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BACKGROUND: There is still no general consensus on the optimal chemotherapeutic agent selection for transcatheter arterial chemoembolization (TACE) in unresectable hepatocellular carcinoma (HCC). The present study aimed to compare the efficacy and safety of TACE with raltitrexed plus liposomal doxorubicin (R + PGLD) vs. tegafur plus pirarubicin (T + P) in patients with unresectable HCC. METHODS: A total of 148 patients with unresectable HCC treated with TACE between January 2012 and December 2016 were retrospectively analyzed. Of them, 74 patients were in the R + PGLD group and 74 patients were in the T + P group (1:1). The treatment response of the tumor, overall survival (OS) time, and adverse effects were compared between the two groups. RESULTS: There were no significant differences in patient characteristics or embolization effect (lipiodol deposition) between the two groups (P>0.05). R + PGLD treatment had a better clinical efficacy than T + P treatment (OR: 64.9% vs. 45.9%, P=0.031; DC: 89.2% vs. 74.3%, P=0.032). Portal vein invasion, hepatic vein invasion, tumor size and BCLC stage were associated with OR or DC after TACE using R + PGLD treatment. Survival analysis revealed that patients who received TACE with R + PGLD had a better prognosis than those treated with T + P. Moreover, some complications in the R + PGLD group, including vomiting, myelosuppression and cardiotoxicity, were significantly lower than those in the T + P group (P<0.05). CONCLUSIONS: TACE with raltitrexed and liposomal doxorubicin could reduce the incidence of adverse reactions and significantly improve the OS of patients with unresectable HCC.
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Crop production, including mushroom farming, may cause significant changes to the underlying substrates which in turn, can influence crop quality and quantity during subsequent years. Here in this study, we analyzed the production of the medicinal mushroom Ganoderma lingzhi and the associated soil microbial communities and soil chemical features over 24 months from April 2015 to April 2017. This Basidiomycete mushroom, known as Lingzhi in China, is commonly found on dead trees and wood logs in temperate and subtropical forests. Its economic and medicinal importance have propelled the development of a diversity of cultivation methods. The dominant method uses wood logs as the main substrate, which after colonization by Lingzhi mycelia, are buried in the soil to induce fruiting. The soil microbial communities over the 24 months were analyzed using the Illumina HiSeq platform targeting a portion of the bacterial 16S rRNA gene and the fungal internal transcribed spacer 1 (ITS1). Overall, a significant reduction of Lingzhi yield was observed over our experimentation period. Interestingly, temporal changes in soil microbial compositions were detected during the 24 months, with the fungal community showing more changes than that of bacteria in terms of both species richness and the relative abundance of several dominant species after each fruiting. The soil chemical features also showed significant changes, with decreasing soil nitrogen and phosphorus concentrations and increasing soil pH and iron content after each fruiting. We discuss the implications of our results in sustainable Lingzhi production in soil.
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Bactérias , Produção Agrícola , Microbiota , Reishi/imunologia , Microbiologia do Solo , Solo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimentoRESUMO
The formation and accumulation of hydrates in high pressure oil and gas pipelines bring great risks to field development and deep-water transportation. In this paper, a high pressure flow loop equipped with visual window was used to study the growth process of hydrates in a pipe flow system and slurry flow characteristics. Deionized water, industrial white oil and CO2 were selected as the experiment medium. A series of experiments with different initial pressures (2.5-3 MPa), liquid loads (7-9 L), flow rates (25-35 kg min-1) and water cuts (60-100%) were designed and carried out. Specifically, hydrate formation and slurry flow characteristics in two different systems, pure water and oil-water emulsion system, were compared. Both of the systems experienced an induction stage, slurry flow stage and followed by a plugging stage. Although hydrate growth gradually ceased in the slurry flow stage, plugging still occurred due to the continuous agglomeration of hydrates. Visual observation showed that there were obvious stratification of the oil-water emulsion systems at the later time of slurry flow stage, which directly resulted in pipe blockage. The hydrate induction time of the flow systems gradually decreased with the increasing initial pressure, initial flow rate and water content. And the induction time tended to decrease first and then slowly increase with the increasing liquid loading. For emulsion systems, the apparent viscosity and friction coefficient of the hydrate slurry increased with the increasing water content, indicating that there were higher plugging risks compared to the pure water systems. Moreover, the results of sensitivity analysis showed that the water content was the main factor affecting the hydrate induction time, followed by the influence of liquid carrying capacity and flow rate, and the initial pressure had the least influence on the induction time. Conclusions obtained in this paper can provide some reference not only for the prevention and management of hydrates in pipelines, but also for the application of CO2 hydrate as a refrigerant.
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The initiation and evolution of the localized corrosion in carbon steel were investigated in a simulated marine environment of Xisha Island in the South China Sea. In the initial stage, localized corrosion occurred in the form of corrosion spot. The localized corrosion morphology and electrochemical information during corrosion process were tracked by field emission scanning electron microscopy energy dispersive spectrometry (FE-SEM-EDS), scanning vibrating electrode technique (SVET) and scanning Kelvin probe force microscopy (SKPFM). Localized corrosion was induced by the microcrevices around Al2O3 inclusions. The occluded cells and oxygen concentration cell formed in the pits could accelerate the localized corrosion. Pearlite accelerated the dissolution of the inside and surrounding ferrite via the galvanic effect between Fe3C and ferrite. Overall, the localized corrosion was initiated and evaluated under a synergistic effect of crevice corrosion, occluded cells, oxygen concentration cell and the galvanic couple between FeC3 and ferrite.
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BACKGROUND: Laparoscopic splenectomy (LS) is regarded as a second-line treatment for medically refractory idiopathic thrombocytopenic purpura (ITP), but the predictive factors for the long-term postoperative responses to ITP are still a matter of debate. We aimed to investigate the factors that can predict the long-term response after LS for Chinese patients with medically refractory ITP. METHODS: From January 2011 to September 2016, 78 Chinese patients with ITP who underwent LS were retrospectively analyzed. Twelve parameters were analyzed by univariate and multivariate methods. RESULTS: Univariate analysis revealed that platelet count on preoperative day (PRD) 1 (P < 0.001) and operative time (P = 0.011) were significantly associated with long-term response of ITP after LS. Multivariate analysis revealed that platelet count on PRD 1 was a predictive factor of long-term response (P < 0.001). Furthermore, a long-term, stable response of platelet count on PRD 1 of > 30.0 × 109/L was easier to achieve than a platelet count on PRD 1 ≤ 30.0 × 109/L after LS for ITP. CONCLUSIONS: LS is a valuable and effective option in the treatment of medically refractory ITP. Platelet count on PRD 1 is an independent predicting factor for long-term response after LS for Chinese patients with ITP.
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Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/cirurgia , Esplenectomia/métodos , Adolescente , Adulto , Idoso , Povo Asiático , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Prognóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Superhydrophobic materials hold great promise in emulsion separation, but they have inherent mechanical weakness and are ineffective to separate mixed surfactant-stabilized emulsions. Herein, we combined the adhesion ability of polyphenol-Fe3+ bis-complexes with the high mechanical strength of carbon nanotubes (CNTs) to construct a mechanically robust and superhydrophobic coating on a collagen fiber membrane (CFM). We demonstrated that both CNTs and polyphenolic complexes competed with the surfactants adsorbed onto the emulsion droplets, serving as efficient demulsifiers to various mixed surfactant-stabilized emulsions. CFM has a 3D fibrous structure and a high limiting oxygen index, which provides high flux and flame resistance. The as-prepared superhydrophobic membrane can separate diverse anionic/nonionic and cationic/nonionic surfactant-stabilized micro- and nanoemulsions under gravity, with a separation efficiency and flux up to 99.999 % and 1695â L m-2 h-1 , respectively. The membranes also retained the emulsion separation ability after sandpaper abrasion. These features demonstrate a practical technology for emulsion separation.
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Using vermicompost (CV) as raw material, its biochar (CVC350) was prepared at 350â and then their physio-biochemical properties were characterized. Furthermore, adsorption studies were performed in a batch system for removing Pb2+ and Cd2+ ions from solution. The characterization results revealed much higher surface area, smaller pore size, greater aromaticity and nonpolarity of CVC350 as compared to CV. Batch adsorption experiments revealed that both the adsorption of Pb2+ and Cd2+ onto CV or CVC350 fitted Langmuir isotherm model very well, and the maximum adsorption capacity of Pb2+ was in the order of CVC350>CV, but no difference was observed for the adsorption capacity of Cd2+ between CV and CVC350. The desorption studies showed that both CV and CVC350 had much higher adsorption rate for Pb2+ than that for Cd2+, and the Cd2+ adsorbed could be more easily desorbed from CV and CVC350 compared with that for the Pb2+ adsorbed. Both the dynamic adsorption process of Pb2+ onto CV and CVC350 was a rapid process, however, the adsorption process of Cd2+ onto CV and CVC350 could be separated into the first rapid step and the second slower step. The adsorption capacity of Pb2+ or Cd2+ onto CV and CVC350 was only affected by the much lower initial pH of the solution, besides, the adsorption capacity of Cd2+ onto CV and CVC350 was relatively more influenced by the initial pH compared with that of Pb2+. Moreover, FTIR analysis showed that the adsorption of Pb2+ and Cd2+on CV depended on the active sites such as aliphatic alcohol, aliphatic acid,carbonates as well as phosphate while that on CVC350 mainly relied on aromatic alcohol, aromatic acid and carbonates.
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Cádmio/isolamento & purificação , Carvão Vegetal , Chumbo/isolamento & purificação , Esterco , Poluentes do Solo/isolamento & purificação , Adsorção , Animais , Bovinos , Feminino , CinéticaRESUMO
PURPOSE: To evaluate the effect of different acid etching modes on bond strength between composite resin and non-carious sclerotic dentin, and to provide references for clinical application. MOTHODS: Thirty premolars with naturally-occurring non-carious cervical lesions were divided into 2 groups based on self-etch adhesive system AdperTM Easy one (AEO) and total-etch adhesive system AdperTM Single Bond2 (ASB2). Each group was further divided into 3 subgroups (ASB21, ASB22, ASB23, AEO1, AEO2, AEO3) and subjected to the following processing: ASB21 subgroup was etched for 15 s with 35% phosphoric acid and coated with binder for 15 s; ASB22 subgroup was etched for 30 s with 35% phosphoric acid and coated with binder for 15 s; ASB23 subgroup was etched for 15 s with 35% phosphoric acid and coated with binder for 30 s; AEO1 subgroup was only etched with binder for 20 s; AEO2 subgroup was etched with binder for 40 s; AEO3 subgroup was etched for 15 s with 35% phosphoric acid and coated with binder for 20 s. The samples were restored with composite resin; 24 h after saved in distilled water at room temperature, the teeth were cut into dumbbell-shaped specimens with surface areas of approximately 1.0 mm2. The microtensile bond strength (µTBS) was detected and evaluated by one-way ANOVA and SNK-q test using SPSS 17.0 software package. RESULTS: µTBS was given in MPa: AEO3>ASB22>ASB23>ASB21>AEO2>AEO1, AEO3 resulted in statistically highest bond strength and AEO1 had the lowest bond strength (P<0.05), ASB22 acquired bond strength just lower than AEO3 (P<0.05). CONCLUSIONS: Use of total-etch adhesive system increasing the etching time of phosphoric time can enhance bond strength. For self-etch adhesive system,both duplicated the time of adhesive treatment and use of phosphoric acid can improve the bond strength. Use of phosphoric acid to etch for 15 s and coated with self-etch adhesive system for 20 s achieved the highest bond strength. In either self-etch or total-etch adhesive system, use of phosphoric acid to etch for 15 s and coated with self-etch adhesive system for 20 s achieved optimal bond strength, there was the lowest bond strength when the self-etch adhesive system used as recommended time.