Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chemosphere ; 355: 141776, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522667

RESUMO

The efficient removal of phosphate from water environments was extremely significant to control eutrophication of water bodies and prevent further deterioration of water quality. In this study, oxygen vacancy-rich magnesium oxide (OV-MgO) microspheres were synthesized by a simple solvothermal method coupling high-temperature calcination. The effects of adsorbent dosage, contact time, initial pH and coexisting components on phosphate adsorption performance were examined. The physicochemical properties of OV-MgO microspheres and the phosphate removal mechanisms were analyzed by various characterization techniques. The maximum adsorption capacity predicted by the Sips isotherm model was 379.7 mg P/g for OV-MgO microspheres. The phosphate adsorption in this study had a fast adsorption kinetics and a high selectivity. OV-MgO microspheres had a good acid resistance for phosphate adsorption, but their adsorption capacity decreased under alkaline conditions. The electrostatic attraction, ligand exchange, surface precipitation, inner-sphere surface complexation and oxygen vacancy capture were mainly responsible for efficient removal of phosphate from aqueous solutions. This study probably promoted the development of oxygen vacancy-rich metal (hydr)oxides with potential application prospects.


Assuntos
Fosfatos , Poluentes Químicos da Água , Fosfatos/química , Óxido de Magnésio/química , Microesferas , Poluentes Químicos da Água/análise , Cinética , Adsorção
2.
Res Sq ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38464117

RESUMO

Background: Neurofilament Light (NfL) is a biomarker for early neurodegeneration in Alzheimer's disease (AD). This study aims to examine the association between plasma NfL and multi-modal neuroimaging features across the AD spectrum and whether NfL predicts future tau deposition. Methods: The present study recruited 517 participants comprising Aß negative cognitively normal (CN-) participants (n = 135), CN + participants (n = 64), individuals with mild cognitive impairment (MCI) (n = 212), and those diagnosed with AD dementia (n = 106). All the participants underwent multi-modal neuroimaging examinations. Cross-sectional and longitudinal associations between plasma NfL and multi-modal neuro-imaging features were evaluated using partial correlation analysis and linear mixed effects models. We also used linear regression analysis to investigate the association of baseline plasma NfL with future PET tau load. Mediation analysis was used to explore whether the effect of NfL on cognition was mediated by these MRI markers. Results: The results showed that baseline NfL levels and the rate of change were associated with Aß deposition, brain atrophy, brain connectome, glucose metabolism, and brain perfusion in AD signature regions. In both Aß positive CN and MCI participants, baseline NfL showed a significant predictive value of elevating tau burden in the left medial orbitofrontal cortex and para-hippocampus. Lastly, the multi-modal neuroimaging features mediated the association between plasma NfL and cognitive performance. Conclusions: The study supports the association between plasma NfL and multi-modal neuroimaging features in AD-vulnerable regions and its predictive value for future tau deposition.

3.
Opt Express ; 31(16): 25900-25914, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710464

RESUMO

Thermal blooming (TB) is one of the important factors affecting the quality of high-energy laser beams. Reasonable simulation of thermal blooming is important to the application of a high-energy laser. However, reported investigations on TB simulation are mainly based on one method, such as the perturbation method or the phase screen method, which often leads to obvious errors in some conditions. In the paper, the reasonable ranges of optical generalized distortion parameters for both methods are determined based on the reported experimental data, which solves the problem of accurate TB simulations for the first time. In addition, the dynamic effect of thermal blooming is also calculated. Finally, the formula method is presented to extract the phase of thermal blooming distortion. We then use LC-SLM (Liquid crystal spatial light modulator) to emulate thermal blooming effect in the lab. The experimental results are more consistent with the numerical simulation results than conventional phase extraction methods. Our work provides a quantitatively and programmable way to accurately simulate TB with LC-SLM in the lab.

4.
Network ; 34(3): 174-189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37218163

RESUMO

BACKGROUND: The use of shorter TR and finer atlases in rs-fMRI can provide greater detail on brain function and anatomy. However, there is limited understanding of the effect of this combination on brain network properties. METHODS: A study was conducted with 20 healthy young volunteers who underwent rs-fMRI scans with both shorter (0.5s) and long (2s) TR. Two atlases with different degrees of granularity (90 vs 200 regions) were used to extract rs-fMRI signals. Several network metrics, including small-worldness, Cp, Lp, Eloc, and Eg, were calculated. Two-factor ANOVA and two-sample t-tests were conducted for both the single spectrum and five sub-frequency bands. RESULTS: The network constructed using the combination of shorter TR and finer atlas showed significant enhancements in Cp, Eloc, and Eg, as well as reductions in Lp and γ in both the single spectrum and subspectrum (p < 0.05, Bonferroni correction). Network properties in the 0.082-0.1 Hz frequency range were weaker than those in the 0.01-0.082 Hz range. CONCLUSION: Our findings suggest that the use of shorter TR and finer atlas can positively affect the topological characteristics of brain networks. These insights can inform the development of brain network construction methods.


Assuntos
Imageamento por Ressonância Magnética , Descanso , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos
5.
Int J Mol Med ; 51(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36928163

RESUMO

The motility of the gallbladder (GB) involves the storage, concentration and delivery of bile. GB motor functions are controlled by multiple complex factors, such as extrinsic and intrinsic innervation, humoral factors and neuropeptides. GB emptying results from coordinated contractions of the muscular layers of the GB wall. Depolarization of GB smooth muscle (GBSM) depends on the activation of the regular depolarization­repolarization potential, referred to as slow waves (SWs). These rhythmic SWs of GBSM contraction are mediated by several cell types, including smooth muscle cells (SMCs), GB neurons, telocytes (TC) and specialized pacemaker cells called interstitial cells of Cajal (ICC). The present article introduced a new GB motor unit, the SMC­TC­ICC­neuron (STIN) syncytium. In GB, STIN cells provide pacemaker activity, propagation pathways for SWs, transduction of inputs from motor and sensory neurons and mechanosensitivity. The present review provided an overview of STIN cells, mechanisms generating GBSM contractile behavior and GB motility, and discussed alterations of STIN cell function under different disease conditions.


Assuntos
Células Intersticiais de Cajal , Vesícula Biliar , Miócitos de Músculo Liso , Células Gigantes , Neurônios , Motilidade Gastrointestinal/fisiologia
6.
J Environ Manage ; 329: 117104, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36603322

RESUMO

The quantitative description of the equilibrium data by the isotherm models is an indispensable link in adsorption studies. The previous review papers focus on the underlying assumptions, fitting methods, error functions and practical applications of the isotherm models, usually ignoring their curve characteristics, selection criteria and common controversies. The main contents of this review include: (i) effect of the model parameters on the isotherm curves; (ii) determination of the site energy distribution; (iii) selection criteria of the isotherm models; and (iv) elimination of some common controversies. It is of great significance to reveal the curve characteristics for selecting a proper isotherm model. The site energy distribution is conducive to understanding the physicochemical properties of the adsorbent surface. The complete isotherm is recommended to be correlated with the experimental data. The model parameter qmax should be cautiously adopted for comparison of the adsorbent performance. The residual plot can be used to diagnose the fitting quality of the isotherm models further. This review also addresses some common mistakes and controversies and thereby avoids their propagation in future publications.


Assuntos
Adsorção , Cinética
7.
Opt Express ; 30(24): 43590-43600, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523054

RESUMO

The unique performances of Epsilon-near-zero (ENZ) materials allow them to play a crucial role in many optoelectronic devices and have spawned a wide range of inventive uses. In this paper, we found that the modified PEDOT:PSS film formed with a kind of so-called "Metastable liquid-liquid Contact (MLLC)" solution treatment method can achieve a wide tuning of ENZ wavelength from 1270 nm to 1550 nm in the near-infrared region. We further analyzed the variation trend of imaginary permittivity for these samples with different ENZ wavelengths. The Berreman mode was successfully excited by a simple structural design to realize a tunable polarization absorber.

8.
Hum Brain Mapp ; 43(11): 3498-3507, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426973

RESUMO

Hierarchy is a fundamental organizational principle of the human brain network. Whether and how the network hierarchy changes in Alzheimer's disease (AD) remains unclear. To explore brain network hierarchy alterations in AD and their clinical relevance. Forty-nine healthy controls (HCs), 49 patients with mild cognitive impairment (MCI), and 49 patients with AD were included. The brain network hierarchy of each group was depicted by connectome gradient analyses. We assessed the network hierarchy changes by comparing the gradient values in each network across the AD, MCI, and HC groups. Whole-brain voxel-level gradient values were compared across the AD, MCI, and HC groups to identify abnormal brain regions. Finally, we examined the relationships between altered gradient values and clinical features. In the secondary gradient, the posterior default mode network (DMN) gradient values decreased significantly in patients with AD compared with HCs. Regionally, compared with HCs, both MCI and AD groups showed that most of the brain regions with increased gradient values were located in anterior DMN, while most of the brain regions with decreased gradient values were located in posterior DMN. The decrease of gradients in the left middle occipital gyrus was associated with better logical memory performance. The increase of gradients in the right middle frontal gyrus was associated with lower rates of dementia. The network hierarchy changed characteristically in patients with AD and was closely related to memory function and disease severity. These results provide a novel view for further understanding the underlying neuro-mechanisms of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Conectoma , Encéfalo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa
9.
J Coll Physicians Surg Pak ; 32(1): 105-107, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34983159

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver cancer. Hepatectomy and transcatheter arterial chemoembolisation (TACE) are generally accepted methods for the treatment of huge HCCs, but the most appropriate treatment is still controversial. We report a 43-year woman with giant HCC, who successfully underwent surgery. The patient was admitted with persistent right upper abdominal pain and fever. Before operation, we assessed the residual liver function and reserve capacity of the patient, and excluded the relevant surgical contra-indications. The results showed that the patient could tolerate surgical treatment, so we performed HCC resection, and the patient was successfully treated. Individualised treatment should be carried out according to tumor factors, baseline liver function and patient's functional status, so as to maximise the benefit to patients. Key Words: Huge hepatocellular carcinoma, Hepatectomy, TACE.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirurgia , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Estudos Retrospectivos
10.
Clin Imaging ; 81: 62-66, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34607094

RESUMO

PURPOSE: To survey the occurrence rate of ascites in patients with thecoma-fibroma and its potential correlation with tumor MR imaging characteristics. METHODS: A total of 40 patients with surgically proven thecoma-fibroma were enrolled in this retrospective study. We determined the tumor size, the components (solid or cystic) and their signal intensity features. Second, we identified ascites according to the fat-suppressed sagittal T2-weighted imaging sequence and divided all cases into two groups (with or without ascites). Furthermore, we explored the correlations of ascites with tumor size, tumor solidity, pathological types, patient's postmenopausal status and serum CA-125 levels by using the χ2 test. RESULTS: (1) Among the 40 cases, 15 tumors were fibromas, 15 thecomas, and 10 fibrothecomas. Nine patients (26.47%) had elevated CA-125 levels (>35.0 U/ml). (2) Thirty-one patients had ascites (77.50%), 29 of which had a small amount of ascites. Nine cases had no ascites (22.50%). (3) MRI showed a solid mass in 22 cases (55.0%), cystic mass in five cases (12.5%) and mixed solid-cystic mass in 13 cases (32.5%). The χ2 test revealed that the incidence of ascites was significantly correlated with tumor size, tumor solidity and serum CA-125 levels (P < 0.05), but not with menopause and pathological type (P > 0.05). CONCLUSION: Our data revealed that the incidence of ascites was 77.50% and was mainly correlated with tumor size and elevated CA-125 levels. These findings have potential value for improving the diagnosis and differential diagnosis of thecoma-fibroma.


Assuntos
Fibroma , Neoplasias Ovarianas , Tumor da Célula Tecal , Feminino , Fibroma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neoplasias Ovarianas/diagnóstico por imagem , Estudos Retrospectivos , Tumor da Célula Tecal/diagnóstico por imagem , Tumor da Célula Tecal/epidemiologia
11.
J Phys Chem B ; 125(30): 8494-8501, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34296879

RESUMO

The Bohart-Adams model was one of the most widely used breakthrough models in column experiments. However, it usually provided a poor fit for the modeling of an asymmetric breakthrough curve. This work proposed the n-order Bohart-Adams and fractal-like Bohart-Adams models. The former indicated a nonlinear decay process of the concentration of the adsorbate or residual capacity of the adsorbent, while the latter reflected a diffusion-limited process on the heterogeneous surfaces. The Bohart-Adams and modified Bohart-Adams models were mathematically equivalent. The applicability of the n-order Bohart-Adams and fractal-like Bohart-Adams models was validated by norfloxacin and Cu(II) adsorption in a fixed-bed column. Compared with the Bohart-Adams model, the two new models had better fitting performance with higher R2 and lower χ2 values, and all of the residuals were randomly distributed. The fractal-like Bohart-Adams and modified dose-response models provided the best fitting quality for the adsorption of Cu(II) (R2 = 0.9956 and χ2 = 7.56 × 10-4) and norfloxacin (R2 = 0.9991 and χ2 = 1.37 × 10-4), respectively. This work may provide a practical method for the modeling of the asymmetric breakthrough curves.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Difusão
12.
Front Aging Neurosci ; 13: 788765, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111039

RESUMO

Mild cognitive impairment (MCI) reversion refers to patients with MCI who revert from MCI to a normal cognitive state. Exploring the underlying neuromechanism of MCI reverters may contribute to providing new insights into the pathogenesis of Alzheimer's disease and developing therapeutic interventions. Information on patients with MCI and healthy controls (HCs) was collected from the Alzheimer's Disease Neuroimaging Initiative database. We redefined MCI reverters as patients with MCI whose logical memory scores changed from MCI to normal levels using the logical memory criteria. We explored intrinsic brain activity alterations in MCI reverters from voxel, regional, and whole-brain levels by comparing resting-state functional magnetic resonance imaging metrics of the amplitude of low-frequency of fluctuation (ALFF), the fractional amplitude of low-frequency fluctuation (fALFF), percent amplitude of fluctuation (PerAF), regional homogeneity (ReHo), and degree centrality (DC) between MCI reverters and HCs. Finally, partial correlation analyses were conducted between cognitive scale scores and resting-state functional magnetic resonance imaging metrics of brain regions, revealing significant group differences. Thirty-two patients with MCI from the Alzheimer's Disease Neuroimaging Initiative database were identified as reverters. Thirty-seven age-, sex-, and education-matched healthy individuals were also enrolled. At the voxel level, compared with the HCs, MCI reverters had increased ALFF, fALFF, and PerAF in the frontal gyrus (including the bilateral orbital inferior frontal gyrus and left middle frontal gyrus), increased PerAF in the left fusiform gyrus, and decreased ALFF and fALFF in the right inferior cerebellum. Regarding regional and whole-brain levels, MCI reverters showed increased ReHo in the left fusiform gyrus and right median cingulate and paracingulate gyri; increased DC in the left inferior temporal gyrus and left medial superior frontal; decreased DC in the right inferior cerebellum and bilateral insular gyrus relative to HCs. Furthermore, significant correlations were found between cognitive performance and neuroimaging changes. These findings suggest that MCI reverters show significant intrinsic brain activity changes compared with HCs, potentially related to the cognitive reversion of patients with MCI. These results enhance our understanding of the underlying neuromechanism of MCI reverters and may contribute to further exploration of Alzheimer's disease.

13.
Environ Sci Pollut Res Int ; 27(35): 43865-43869, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32740844

RESUMO

Besides adsorption rate constant, the half-life was also a basic factor that described the characteristics of adsorption kinetics. However, the direct prediction of the half-life was still a problem to be addressed urgently. In this work, the parameter τ was introduced into the pseudo-first-order (PFO), pseudo-second-order (PSO), pseudo-nth-order (PNO), and the corresponding fractal-like kinetic models (fractal-like PFO, fractal-like PSO, and fractal-like PNO) to directly predict the half-life by changing the boundary condition, i.e., the replacement of qt = 0, t = 0 by qt = qe/2, t = τ. The fitting performance of these kinetic models after modification was evaluated by nitrate adsorption on polyaniline-modified activated carbon (PAN/AC) and phosphate adsorption on zirconium-loaded Ca-montmorillonite. The results indicated that this type of model modifications did not influence the fitting performance and that the half-life was easily obtained only by the curve fitting. The practical significance of this work was to simultaneously predict the adsorption rate constant and half-life using the modified kinetic models.


Assuntos
Bentonita , Poluentes Químicos da Água , Adsorção , Meia-Vida , Concentração de Íons de Hidrogênio , Cinética , Fosfatos
14.
Water Res ; 179: 115728, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32359772

RESUMO

In the adsorption studies, the accurate estimation of the model parameters contributes to getting insights into adsorption behaviors and optimizing adsorber design. After reading the research work of Pap et al. (2020) carefully, it was found that the fitting results were questionable. Thus, this comment tried to address the following aspects: (i) Correction of the fitting results for the kinetic and isotherm models; (ii) Correct form of the Bohart-Adams model; (iii) Usage of the Clark model; and (iv) Effects of the partial or complete experimental data on the model parameters. This work is expected to help readers better understand the adsorption models and estimate the model parameters.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Carbonato de Cálcio , Cinética , Fosfatos , Águas Residuárias
15.
J Hazard Mater ; 394: 122508, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32248027

RESUMO

The Bohart-Adams model has been one of the most widely used breakthrough models for the modeling of dynamic adsorption behaviors of water pollutants in a fixed-bed column. However, the fitting quality was often questioned by many researchers when the Bohart-Adams model was correlated with the experimental data. Recently, Chu (2020) discussed the two simplified forms of the Bohart-Adams model and tested their applicability. In fact, in our previous study (Hu et al., 2019), it has been proved that the two forms represented the logistic and exponential functions in mathematical nature, respectively. The fitting quality depended on whether the experimental data approached the shape of the model curve. Besides, the curve characteristics and fitting ability of the original Bohart-Adams model were not revealed, and how to analyze asymmetrical breakthrough curve remained to be solved. This comment tried to expound the Bohart-Adams model completely. The authors hope that this work will be helpful for readers who are interested in the adsorption studies.

16.
Sci Total Environ ; 709: 136123, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31905557

RESUMO

The situation of eutrophication and shortage of phosphorus resources have triggered the development of new methods for the removal and recovery of phosphorus. In this study, a novel and highly efficient composite (nano-CaO2/BC) was fabricated by using the porous biochar (BC) to load calcium peroxide (CaO2) nanoparticles. The developed nano-CaO2/BC was applied to remove and recover phosphate from P-contained sewage. The phosphate removal performance of the composite was examined using the bulk solutions with different pH values, coexisting anions, composite dosages, and initial phosphate concentrations. The phosphate adsorption was a typical chemisorption process that agreed well with the pseudo-second-order kinetic model. Isotherm studies showed that the adsorption matched well with Langmuir-Freundlich and the maximum adsorption capacity at equilibrium was 213.22 ± 13.57 mg g-1 (298 K). The characterization results demonstrated that the predominant adsorption mechanism was precipitation. Moreover, the composite had good reusability. The seedling growth test confirmed that the P-laden composite can be mixed with soil to promote the growth of seedlings. Therefore, the method of "cycle back to soil" of used composite provided a way of resource utilization and waste disposal.

17.
Ecol Evol ; 9(18): 10432-10441, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31624558

RESUMO

Understanding the distribution and composition of soil microbes in bare patches is a critical step to improving ecological remediation. The effects of different vegetative restoration types on soil microbes within semi-arid bare patches remain unclear. Here, we evaluated the distribution of soil fungi and bacteria among different ecological restoration types at the southern Taihang Mountains. Analysis of variance showed that the chemical properties of soil with vegetation cover have higher nutrient quality than those of the exposed soil. The results also suggested that vegetative restoration significantly improved the diversity and the richness of the soil fungal and bacterial communities. Sequencing results showed that Ascomycota and Basidiomycota were the main soil fungal communities, whereas Proteobacteria, Acidobacteria, and Actinobacteria were the main soil bacterial communities. There were significant relationships between the contents of moisture, organic matter and organic carbon and the soil fungal/bacterial communities. Venn and network diagrams indicated that the vegetative restoration types largely influenced the soil fungi and weakly influenced the soil bacteria in the bare patches. This study discusses the importance of vegetative restoration in the ecological remediation of bare patches. These findings provide effective references for soil restorative measures, water conservation, and bare-spot reduction at the southern Taihang Mountains in future.

18.
Sci Rep ; 7(1): 581, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28373667

RESUMO

Acute pancreatitis (AP) is a common acute abdominal disease, 10-20% of which can evolve into severe AP (SAP) causing significant morbidity and mortality. Bone marrow-derived mesenchymal stem cells (BMSCs) have the potential of repairing SAP, but the detailed mechanism remains unknown. We demonstrate here that microRNA-9 (miR-9) modified BMSCs (pri-miR-9-BMSCs) can significantly reduce the pancreatic edema, infiltration, hemorrhage, necrosis, the release of amylase and lipase. Meanwhile, decreased local/systemic inflammatory response (TNF-α↓, IL-1ß↓, IL-6↓, HMGB1↓, MPO↓, CD68↓, IL-4↑, IL-10↑, and TGF-ß↑) and enhanced regeneration of damaged pancreas (Reg4↑, PTF1↑, and PDX1↑) are also promoted. But these effects diminish or disappear after antagonizing miR-9 (TuD). Besides, we find that miR-9 is negatively correlated with AP and miR-9 agomir which can mimic the effects of pri-miR-9-BMSCs and protect injured pancreas. Furthermore, we investigate that BMSCs deliver miR-9 to the injured pancreas or peripheral blood mononuclear cell (PBMC), which can target the NF-κB1/p50 gene and inhibit the NF-κB signaling pathway (p-P65↓, NF-κB1/p50↓, IκBα↑, IκBß↑). Taken together, these results show that miR-9 is a key paracrine factor of BMSCs attenuating SAP targeting the NF-κB1/p50 gene and suppressing the NF-κB signaling pathway.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Subunidade p50 de NF-kappa B/genética , Pancreatite Necrosante Aguda/etiologia , Animais , Apoptose/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Subunidade p50 de NF-kappa B/metabolismo , Pancreatite Necrosante Aguda/metabolismo , Pancreatite Necrosante Aguda/patologia , Pancreatite Necrosante Aguda/terapia , Interferência de RNA , Ratos , Transdução de Sinais , Fatores de Tempo , Transdução Genética
19.
Bioresour Technol ; 218: 307-17, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27372011

RESUMO

An up-flow partially aerated biological filter (U-PABF) was developed to study the removal of nitrogen and chemical oxygen demand (COD) from synthetic domestic wastewater. The removal of NH4(+)-N was primarily attributed to adsorption in the zeolite U-PABF and to bioprocesses in the ceramic U-PABF. When the hydraulic retention time (HRT) was 5.2h, the ceramic U-PABF achieved a good performance and the NH4(+)-N, total nitrogen (TN), and COD removal efficiency reached 99.08±8.79%, 72.83±0.68%, and 89.38±1.04%, respectively. The analysis of NH4(+)-N, NO3(-)-N, NO2(-)-N, and TN at different depths revealed the simultaneous existence of nitrification-denitrification, and anaerobic ammonium oxidation (anammox) in ceramic U-PABF. Illumina pyrosequencing confirmed the existence of Planctomycetes, which are responsible for anammox. The results indicated that the nitrification-denitrification and anammox all contributed to the high removal of NH4(+)-N, TN, and COD in the U-PABF.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Bactérias , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , Desnitrificação , Nitrificação , Nitrogênio , Águas Residuárias/microbiologia
20.
Water Sci Technol ; 73(5): 1211-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26942545

RESUMO

In the present study, a granular chitosan-Fe(III) complex was prepared as a feasible adsorbent for the removal of nitrate from an aqueous solution. There was no significant change in terms of nitrate removal efficiency over a wide pH range of 3-11. Nitrate adsorption on the chitosan-Fe(III) complex followed the Langmuir-Freundlich isotherm model. In order to more accurately reflect adsorption and desorption behaviors at the solid/solution interface, kinetic model I and kinetic model II were proposed to simulate the interfacial process in a batch system. Nitrate adsorption on the chitosan-Fe(III) complex followed the pseudo-first-order kinetic model and kinetic model I. The proposed half-time could provide useful information for optimizing process design. Adsorption and desorption rate constants obtained from kinetic model I and kinetic model II were beneficial to understanding the interfacial process and the extent of adsorption reaction. Kinetic model I and kinetic model II implied that nitrate uptake exponentially approaches a limiting value.


Assuntos
Quitosana/química , Compostos Férricos/química , Nitratos/química , Adsorção , Cinética , Óxidos de Nitrogênio , Poluentes Químicos da Água/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...