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1.
Chemosphere ; 251: 126442, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32169715

RESUMO

This study aimed to compare the effectiveness of MAER and L20 resin for the adsorption treatment of secondary effluent, and evaluate the applicability of ozone oxidation for the reuse of desorption eluate. Bench-scale adsorption experiments showed that the MAER resin exhibited higher efficiency than L20 resin in removal of COD within 600 treated bed volumes (BV), which declined from 32.5% to 14.1% in the first and sixth treatment loading of 100 BV. On the other hand, the L20 resin displayed obviously higher removal efficiency of total nitrogen (TN) than MAER resin within 600 BV, which dropped from 74.6% to 9.8% at the same condition. The ozone oxidation treatment could achieve desirable reuse of desorption eluate, although its chemical oxygen demand (COD) concentration increased gradually in line with the reuse numbers. The uptake of COD, TN and total phosphorus declined steadily by using ozone treated eluate as the regenerant in successive adsorption-desorption cycles, but increased obviously with a new batch of regenerant. Overall, the resin adsorption could efficiently remove organic and inorganic matters from secondary effluent, while the treatment loop including desorption eluate oxidation and eluate reuse could markedly enhance the concentration ratio of treated effluent.

2.
J Hazard Mater ; 393: 122395, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32135366

RESUMO

Transition-metal catalysts (TMCs) for peroxymonosulfate (PMS) activation suffer from low stability (i.e. severe metal leakage and poor reusability) when maintaining high activity in water decontamination. An innovative carbonate (CO32-)-mediated method to synchronously enhance the catalytic activity and stability of TMCs was developed herein. In a model PMS/Co3O4 nanowire system for bisphenol A (BPA) degradation, the first-order kinetic constant and total organic carbon removal ratio were increased by 202.27% and 71.32% upon adding CO32-, respectively. Meanwhile, the cobalt release amount was significantly reduced from 4.90 to 0.03 mg/L, and the number of reuse with high efficiency (>90% of BPA removal within 10 min) was augmented from 1 to 3 times. The CO32- buffered pH decline to repress metal leakage, and promoted Co(III) reduction into Co(II) to avoid the over-oxidation of catalyst. Under the driving of CO32-, the dominated reactive species were switched from •OH/SO4•- to 1O2 accompanying the migration of catalytic center from Co(II) to Co(III). The Co(III) and CO32-/OH- acted as electron and proton acceptors, respectively, to accelerate PMS decomposition into SO5•- and subsequent generation of vast 1O2. This work proposes a green way to construct novel 1O2-based catalytic systems with excellent activity and stability for pollution remediation.

3.
Int J Biol Macromol ; 149: 1285-1293, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32044372

RESUMO

A silica-sand/anionized-starch composite (CMS-SS) was prepared simply. CMS-SS was used as an efficient adsorbent for removal of cationic dyes [methyl blue (MB) and crystal violet (CV)] and metal ions [cupper(II), Cu(II)] from water in respective single and binary systems. Compared with the anionized-starch without silica sand, CMS-SS shows evidently improved adsorption capacities, i.e. approximately 653.31 ± 27.30, 1246.40 ± 34.10, and 383.08 ± 13.50 mg·g-1, for MB, CV, and Cu(II), respectively, ascribed to the additional carboxyl groups. The isotherms and kinetics study indicated that the Langmuir model and the pseudo-second-order model were more suitable. The adsorption process is thus a homogeneous monolayer chemisorption. The adsorptions of these three pollutants are spontaneous and exothermal processes driven by increasing entropy. The adsorption behaviors of CMS-SS have high pH dependence, and electrostatic attraction play an important role in adsorption. Dyes showed higher affinity to CMS-SS than metal ions causing a preferential adsorption of dye over Cu(II) in their aqueous mixture. This adsorbent after saturated adsorption could be rapidly separated from water due to its enlarged density after embedded silica sand; moreover, those rapidly recovered adsorbents were tried to use as new adsorbents for removal of an anionic dye from water due to the complete changes in their surface structures after saturated adsorption.

4.
ACS Appl Mater Interfaces ; 12(10): 12165-12175, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32057224

RESUMO

Natural organic matter (NOM), organic micropollutants (OMPs), and detrimental microorganisms are three major pollutants that affect water quality. To remove these pollutants, a quaternary ammonium-functionalized ß-cyclodextrin polymer (ß-CDP) is successfully synthesized in the aqueous phase. The N2 and CO2 adsorption/desorption analysis showed that the polymer mainly contains ultra-micropores (<1 nm), with a Langmuir surface area of 89 m2 g-1. Two kinds of NOM, humic acid and fulvic acid, and five OMPs, 2-naphthol (2-NO), 3-phenylphenol (3-PH), 2,4,6-trichlorophenol (2,4,6-TCP), bisphenol A (BPA), and bisphenol S (BPS), were selected as model pollutants to study the performance of ß-CDP and three kinds of commercial adsorbents, including granular activated carbon, DARCO-AC, and two resins, XAD-4 and D-201, were used for comparison. The polymer shows ultrarapid adsorption kinetics for the removal of these pollutants, with pseudo-second-order rate constants two to three orders of magnitude higher than that of the commercial activated carbon and resins. Due to the different adsorption sites of NOM and OMPs, ß-CDP can simultaneously remove these pollutants without competitive adsorption. The maximum adsorption capacity of ß-CDP for HA, FA, 2-NO, 3-PH, 2,4,6-TCP, BPA, and BPS based on the Langmuir model is 40, 166, 74, 101, 108, 103, and 117 mg g-1, respectively. After use, the polymer can be easily regenerated at room temperature. In addition, ß-CDP also showed excellent bactericidal properties due to the quaternary ammonium groups. At a concentration of 15 g L-1, ß-CDP can remove 98% of the tested Escherichia coli. Moreover, the synthesis of ß-CDP is simple, green, and easy to industrialize. All of these findings indicate that ß-CDP, as an ideal multifunctional material, presents potential for practical applications for water treatment and disinfection.

5.
Cell Biochem Funct ; 2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32064636

RESUMO

Long noncoding RNAs have been proved in regulating tumourigenesis, including hepatocellular carcinoma (HCC). However, up to date, the role of PCAT6 in HCC is rare to be reported. In current study, bioinformatics analysis and quantitative real-time PCR were applied to examine the expression of PCAT6 in HCC. The role of PCAT6 in cell proliferation, cell cycle arrest, apoptosis, and metastasis were detected in both gain- and loss-of-function studies by cell biological assays. Bioinformatics analysis was employed to investigate the PCAT6-related genes and pathways in HCC. And we found that PCAT6 was significantly upregulated in HCC tissues and correlated with poor overall survival and disease-free survival in HCC patients. Furthermore, elevated PCAT6 promoted cell proliferation, inhibited cell cycle arrest and cell apoptosis while deficiency of PCAT6 impaired cell proliferation, caused cell cycle arrest and induced cell apoptosis of HCC. Moreover, as for bioinformatics analysis, a total of 389 PCAT6-related genes were found in both HCC tissue and cell lines, and these promising target genes were highly enriched in various key pathways, such as Wnt, HIF-1 signalling pathway, and metabolic pathways. Additionally, among these genes, DCAF13, SNRPB2, RPS8, and FKBP1A were revealed to be overexpressed in HCC and predicted poor prognosis. Taken together, our findings illustrate that PCAT6 contributes to HCC progression and might be a potential target for HCC therapy. Bioinformatics analysis may present a new way for assessing the underlying mechanism of PCAT6 in HCC. SIGNIFICANCE OF THE STUDY: Hepatocellular carcinoma (HCC) is one of the most common and malignant tumours all over the world. In this study, we observed that PCAT6 was upregulated in HCC and correlated with poor prognosis of HCC patients. PCAT6 could promote cell proliferation, inhibit cell cycle arrest and cell apoptosis of HCC, suggesting PCAT6 exerts tumorigenic role in HCC. Moreover, bioinformatics analysis revealed a total of 389 PCAT6-related genes in both HCC tissue and cell lines, and these promising target genes were highly enriched in various key pathways, such as Wnt, HIF-1 signalling pathway, and metabolic pathways. These finding provided evidence that PACT6 may be identified as a strategy to treat HCC in the future.

6.
Chemistry ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32056301

RESUMO

The icosahedral [M@Pb12]3- (M = Co(1), Rh(2), Ir(3)) cluster ions were prepared from K4Pb9 and Co(dppe)Cl2 (dppe = 1,2-Bis(diphenylphosphino)ethane) / Rh(PPh3)3Cl / [Ir(cod)Cl]2 (cod = 1,5-cyclooctadiene), respectively, in the presence of 18-crown-6 / 2,2,2-cryptand in ethylenediamine / toluene solvent mixtures. The [K(2,2,2-cryptand)]+ salt of 1 and the [K(18-crown-6)]+ salt of 3 were characterized via X-ray crystallography; the ions 1 and 3 are isostructural and isoelectronic to the [Rh@Pb12]3- (2) ion as well as to  the group 10 clusters [M'@Pb12]2- (M' = Ni, Pd, Pt). The ions are all 26-electron clusters with near perfect icosahedral Ih point symmetry. Clusters 1-3 show record downfield 207Pb NMR chemical shifts due to σ-aromaticity of the cluster framework.  Calculated and observed 207Pb NMR chemical shifts and 207Pb-xM J-couplings (xM = 59Co, 103Rh, 193Ir) are in excellent agreement and DFT analysis shows that the variations of 207Pb-NMR chemical shifts for the [M@Pb12]2,3- ions (M = Co, Rh, Ir, Ni, Pd, Pt) are mainly governed by the perpendicularly oriented s11 component of the chemical shift anisotropy tensor. The laser desorption ionization time-of-flight (LDI-TOF) mass spectra contain the molecular ions as well as several new gas phase clusters derived from the parents. The DFT minimized structures of these ions are described.

7.
J Environ Manage ; 260: 110159, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090846

RESUMO

Sludge treatment wetlands (STWs) can effectively stabilize sludge, but the microbial community structure in this process is not well characterized. The purpose of this study was to investigate the characteristics of organic matter and nutrient removal and bacterial community in sludge treatment wetlands for treating sewage sludge. Three STWs units included unit STW1 with aeration tubes, unit STW2 with aeration tubes and reed planting and unit STW3 with reed planting. The degradation of organic matter and nutrient, sludge dewatering performance and microbial community dynamics in STWs were examined in feeding and resting periods. Our results showed that during the entire process of the experiment, total solids (TS) in STWs increased to 24-31%, volatile solids (VS) in STWs reduced to 43-47%, while the total kjeldahl nitrogen (TKN) and total phosphorous (TP) concentrations in STWs decreased to 25.1-35.5 mg/g d. w and 5.4-6.2 mg/g d. w. However, the removal efficiencies of organic matter and nutrient in STWs in the feeding period were higher than those in the resting period. Meanwhile, unit STW2 has the best removal performance in organic matter and nutrients during the whole experiment. Microbial community analysis using Illumina MiSeq sequencing technology showed that growth of plants in STWs improved bacterial diversity and richness which corresponded to high removal rates of organic matter and nutrient. Besides, principal coordinate analysis (PCoA) showed that the bacterial community composition in STWs obviously altered between the feeding and the resting periods.


Assuntos
Esgotos , Áreas Alagadas , Bactérias , Nutrientes , Fósforo , Eliminação de Resíduos Líquidos
9.
BMC Neurol ; 20(1): 59, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066399

RESUMO

BACKGROUND: Human leukocyte antigen-E (HLA-E) has been extensively investigated in various human cancers including glioma. However, the clinical significance of HLA-E expression in glioma patients has not been elucidated. The current study aimed to investigate the association of HLA-E expression with clinicopathological features and survival in patients with diffuse glioma. METHODS: A total of 261 glioma patients were enrolled, subsequently, mRNA microarray analysis was conducted to identify the relationship of HLA-E with clinicopathological features and patient survival. RESULTS: HLA-E was significantly overexpressed in high-grade gliomas compared to low-grade gliomas (LGGs). Moreover, HLA-E expression was significantly higher in diffuse astrocytomas than oligodendrogliomas (p = 0.032, t-test). Kaplan-Meier analysis showed that progression-free survival (PFS) and overall survival (OS) were significantly better in LGG patients with low HLA-E expression (p = 0.018 for PFS and p = 0.020 for OS, Log-rank test). Furthermore, HLA-E expression was identified to be an independent prognostic factor by Cox analysis (p = 0.020 for PFS and p = 0.024 for OS). CONCLUSIONS: This is the first study which identified the clinical significance of HLA-E in diffuse glioma. HLA-E expression was correlated with more aggressive tumor grade and histological type and was identified as an independent prognostic biomarker in LGG patients.

10.
Sci Rep ; 10(1): 852, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965022

RESUMO

Recent studies have revealed that feed-forward loops (FFLs) as regulatory motifs have synergistic roles in cellular systems and their disruption may cause diseases including cancer. FFLs may include two regulators such as transcription factors (TFs) and microRNAs (miRNAs). In this study, we extensively investigated TF and miRNA regulation pairs, their FFLs, and TF-miRNA mediated regulatory networks in two major types of testicular germ cell tumors (TGCT): seminoma (SE) and non-seminoma (NSE). Specifically, we identified differentially expressed mRNA genes and miRNAs in 103 tumors using the transcriptomic data from The Cancer Genome Atlas. Next, we determined significantly correlated TF-gene/miRNA and miRNA-gene/TF pairs with regulation direction. Subsequently, we determined 288 and 664 dysregulated TF-miRNA-gene FFLs in SE and NSE, respectively. By constructing dysregulated FFL networks, we found that many hub nodes (12 out of 30 for SE and 8 out of 32 for NSE) in the top ranked FFLs could predict subtype-classification (Random Forest classifier, average accuracy ≥90%). These hub molecules were validated by an independent dataset. Our network analysis pinpointed several SE-specific dysregulated miRNAs (miR-200c-3p, miR-25-3p, and miR-302a-3p) and genes (EPHA2, JUN, KLF4, PLXDC2, RND3, SPI1, and TIMP3) and NSE-specific dysregulated miRNAs (miR-367-3p, miR-519d-3p, and miR-96-5p) and genes (NR2F1 and NR2F2). This study is the first systematic investigation of TF and miRNA regulation and their co-regulation in two major TGCT subtypes.

11.
Sci Total Environ ; 712: 136370, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31945537

RESUMO

The aim of this research was to analyze the elimination of nutrients, antibiotics as well as antibiotic resistance genes (ARGs) in different sludge treatment wetlands (STWs) with or without reeds and aeration tubes. Five antibiotics, including oxytetracycline, tetracycline, azithromycin, sulfamethoxazole, and sulfadiazine; five ARGs, including two tetracycline ARGs (tetC and tetA), one macrolide ARGs (ermB), and two sulfonamide ARGs (sul1 and sul2); and one integrase gene (intI1) were determined in the surface and bottom layers of three STWs, respectively. The removal efficiencies of antibiotics in the bottom layer were lower than that in the surface layer, while the elimination efficiencies of ARGs showed opposite trend. Strong correlations were observed among the contents of antibiotics as well as related ARGs, and the abundance of ARGs had a strong correlation with intI1. The results demonstrated that the contents of these pollutants decreased during the resting period in all the STWs, while the wetland had reeds and aeration tubes performed the best.

12.
Water Res ; 172: 115526, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000127

RESUMO

Edible salt is essential to the health of humans and serves as a seasoning universally. Besides chloride, edible salt also contains other anions such as bromide, fluoride, sulfate, and carbonate due to incomplete removal during raw salt refinement. In a household cooking (e.g., soup making) process, a chlorine/monochloramine residual in tap water could react with bromide in edible salt and organic matter in food (e.g., rice, wheat) to form numerous brominated disinfection byproducts (Br-DBPs) at significant levels, which might induce adverse health effects to human beings. In this study, we solicited 20 edible salts of different types (i.e., sea salts, well and rock salts, lake salts, and bamboo salts) from nine countries and determined their bromide levels to be 67-375 mg/kg, with an average level of 173 mg/kg. A total of 25 polar Br-DBPs were detected and identified with structures/formulae in cooking water samples using ultra performance liquid chromatography/electrospray ionization-triple quadruple mass spectrometry (UPLC/ESI-tqMS) and high-resolution mass spectrometry. Effects of cooking conditions (e.g., disinfectant type and level, edible salt dose, organic matter type and dose, sequence and time interval of adding organic matter and salt, etc.) on the formation of polar Br-DBPs were investigated, and optimized cooking conditions with minimized formation of polar Br-DBPs were determined. Further aided with an Hep G2 cell cytotoxicity assay, it was found that the overall cytotoxicity of chlorinated and chloraminated cooking water samples prepared after cooking condition optimization was reduced by 57% and 22%, respectively, compared with those prepared before cooking condition optimization.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Culinária , Desinfecção , Halogenação , Humanos
13.
Water Res ; 171: 115437, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31893554

RESUMO

Despite plenty of literatures focused on the application of pre-ozonation prior to membrane, it was still unclear about the role of divalent cations (Ca2+ and Mg2+) in reverse osmosis (RO) membrane fouling mitigation. In this study, ozone pre-treatment (0.10, 0.25 and 0.50 mg O3/mg DOC (dissolved organic carbon)) was employed to oxidize model biopolymer, which was represented by bovine serum albumin (BSA) and sodium alginate (SA) in the presence of Ca2+ and Mg2+ (0.5, 1.0 and 2.0 mM). Cross-flow filtration was conducted to investigate RO membrane fouling by concentration mode. The results showed that at appropriate ozone dose there were measurable changes in physicochemical properties of BSA and SA, including increases in particle size, hydrophilicity, density of negative charge and carboxylic groups. Pre-ozonation markedly alleviated RO fouling by BSA at ozone dose of 0.25 mg O3/mg DOC when Ca2+ and Mg2+ concentrations raised from 0.5 to 2.0 mM since the increase in electrostatic (EL) repulsion and decrease in hydrophobic (HP) interaction compensated the increase in divalent cation bridging. Similar results were obtained for SA fouling in the presence of Mg2+. In contrast, the effect of pre-ozonation on SA fouling strongly depended on the concentration of Ca2+. In brief, it mitigated SA fouling at 0.5 mM Ca2+, whereas accelerated irreversible fouling at higher Ca2+ concentration (1.0 and 2.0 mM) due to the overwhelming effect of divalent cation bridging compared to EL and HP interactions, as revealed by adsorption experiments (in-situ streaming potential measurement). Pre-ozonation shifted the fouling layer from compact to porous and weakened the adhesion forces between foulants and membrane (foulants) except for SA containing 1.0 and 2.0 mM Ca2+. This study may provide the guidance for the application of pre-ozonation prior to RO filtration.


Assuntos
Ozônio , Purificação da Água , Biopolímeros , Membranas Artificiais , Osmose
14.
J Hazard Mater ; 384: 121492, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31677912

RESUMO

The development of high efficiency filter membranes, particularly those capable of removing trace heavy metals from drinking water sources, is a global challenge. In this study, a dual-functional membrane (PmGn@PVDF) was successfully developed by doping graphene oxide (GO) and then depositing polydopamine (PDA). The pure water flux (Jw) was 188 LMH/bar and Pb(II) could be effectively removed in the water volume of 2106.36 L m-2. Both PDA and GO performed positive functions. PDA layer exhibited a high affinity toward Pb(II) by chelating with amino groups. And doping GO maintained a high pure water flux, which had been decreased by the extra PDA layer. In addition, the effective treatment volume of Pb(II) was elevated to 5029.06 L/m2 by the co-existence of citric acid, since neutral PbHL coordinated with neutral NH2 and cationic PbL- interacted with NH3+ through electrostatic attraction. Furthermore, PmGn@PVDF showed the excellent anti-interference performance in high salt and nature organic matters solutions. Thus, this novel dual-functional membrane could be considered as a competitive alternative of NF/RO for the efficient and advanced removal towards heavy metals from natural water.

15.
Bioresour Technol ; 297: 122382, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31776103

RESUMO

The objective of this study was to evaluate the antagonistic effect of emerging pollutants of zinc oxide nanoparticles (ZnO NPs) and sodium dodecyl sulfate (SDS) on anaerobic digestion and explore their potential mechanism. The results indicated that at a low inhibitory concentration of ZnO NPs (1.0 mM), the practical co-inhibition was decreased by 24% and 18% in co-existence of 50 mg/L SDS and 300 mg/L SDS, respectively. More importantly, the co-existence of 300 mg/L SDS greatly enhanced methanogenesis of organics in seriously inhibited case (2.0 mM of ZnO NPs). The microbial community analysis showed that co-existed SDS enhanced the growth of Methanothrix, Methanosarcina and Methanobacterium. The antagonistic enhancement could be attributed to the net charge reversal, partially agglomeration of ZnO NPs and/or reduction of Zn2+ release in the presence of SDS. These findings could provide useful information for evaluating the co-inhibition of SDS and ZnO NPs on biological processes.


Assuntos
Nanopartículas Metálicas , Microbiota , Nanopartículas , Óxido de Zinco , Anaerobiose , Tensoativos
16.
J Clin Invest ; 130(1): 247-257, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31573981

RESUMO

Brown adipose tissue (BAT), as the main site of adaptive thermogenesis, exerts beneficial metabolic effects on obesity and insulin resistance. BAT has been previously assumed to contain a homogeneous population of brown adipocytes. Utilizing multiple mouse models capable of genetically labeling different cellular populations, as well as single-cell RNA sequencing and 3D tissue profiling, we discovered a brown adipocyte subpopulation with low thermogenic activity coexisting with the classical high-thermogenic brown adipocytes within the BAT. Compared with the high-thermogenic brown adipocytes, these low-thermogenic brown adipocytes had substantially lower Ucp1 and Adipoq expression, larger lipid droplets, and lower mitochondrial content. Functional analyses showed that, unlike the high-thermogenic brown adipocytes, the low-thermogenic brown adipocytes have markedly lower basal mitochondrial respiration, and they are specialized in fatty acid uptake. Upon changes in environmental temperature, the 2 brown adipocyte subpopulations underwent dynamic interconversions. Cold exposure converted low-thermogenic brown adipocytes into high-thermogenic cells. A thermoneutral environment had the opposite effect. The recruitment of high-thermogenic brown adipocytes by cold stimulation is not affected by high-fat diet feeding, but it does substantially decline with age. Our results revealed a high degree of functional heterogeneity of brown adipocytes.

17.
Chemosphere ; 241: 125023, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31606573

RESUMO

Zwitterionic pharmaceuticals and personal care products can interact with adsorbents in different ways due to their various properties. In this work, the effects of hydrophobicity and electrostatic potential were explored through the adsorption of ciprofloxacin (CPX) and tetracycline (TC) onto multifunctional resins. Nonionic surface interaction was dominant for the adsorption on high-surface-area resin GMA10. Thereinto, hydrophobic and π-π interaction dominant for hydrophobic CPX and hydrophilic TC, respectively. Electrostatic interaction played an important role for high-anion-exchange-capacity resin GMA90. Upon their adsorption onto GMA50 resin, the relatively separated positive and negative electrostatic potentials of CPX+- due to the greater distance (∼12.33 Å) between the anionic and cationic groups led to electrostatic attraction and interaction (Ea = 8.64 ±â€¯0.31 kJ/mol) and the vertical orientation of molecule on the surface. However, TC+-0 displayed nonionic surface interaction (Ea = 7.96 ±â€¯0.14 kJ/mol) due to its relatively neutral electrostatic potential arising from the adjacent functional groups. Hence, the surface of GMA50 was covered with TC+-0 molecules adsorbed parallel to the surface, thereby restricting TC+-0 adsorption. Coexisted with monovalent salts, CPX adsorption was facilitated due to the salting-out effect. By contrast, the salting-out effect for TC was extremely weak, and TC adsorption was restrained due to the competitive adsorption of salts.


Assuntos
Adsorção , Resinas de Troca de Ânions/química , Cosméticos/química , Tensoativos/química , Ciprofloxacino/química , Ciprofloxacino/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Resinas Sintéticas/química , Sais , Eletricidade Estática , Tetraciclina/química , Tetraciclina/isolamento & purificação
18.
Br J Cancer ; 122(3): 388-396, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31787749

RESUMO

BACKGROUND: Preoperative prediction of lymph node (LN) status is integral to determining the most appropriate treatment strategy for colorectal cancer (CRC). This study aimed to develop and validate a nomogram to predict LN metastasis in CRC preoperatively. METHODS: A total of 530 patients were enrolled and divided into training and validation cohorts. The tumour stroma percentage (TSP) of the preoperative biopsies was assessed. The risk factors for LN metastasis were selected, and a nomogram was constructed subsequently. The performance of the nomogram was assessed by using the AUROC and the calibration curve, and then validated in the validation cohort. RESULTS: High TSP was significantly associated with LN metastasis in both the training and validation cohorts. Computed tomography (CT)-reported T stage, CT-reported LN status, preoperative tumour differentiation, carcinoembryonic antigen, carbohydrate antigen 19-9 and TSP were independent predictors of LN metastasis in CRC. A nomogram incorporating the six predictors was constructed. The nomogram yielded good discrimination and calibration, with an AUROC of 0.846 (95% CI: 0.807-0.886) and 0.809 (95% CI: 0.745-0.872) in the training and validation cohorts, respectively. CONCLUSIONS: Assessment of TSP in the preoperative biopsies provided additional information about the LN status. The nomogram was useful for tailored therapy in CRC preoperatively.

19.
Chemosphere ; 243: 125321, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31733541

RESUMO

In this study, size exclusion chromatography with an array of absorbance, fluorescence, organic nitrogen and organic carbon detectors was used for characterizing property and treatability of effluent organic matter (EfOM) from 12 wastewater treatment plants. According to their apparent molecular weight (AMW), EfOM fractions were assigned to biopolymers (>20 kDa), humic substances that comprise sub-fractions of humic-like acids (HA-I & HA-II, 2.3-7.0 kDa) and fulvic-like acids (FA, 1.5-2.3 kDa), building blocks (0.55-1.5 kDa) and low molecular weight neutral substances (<550 Da). The fractions of biopolymers and low molecular weight neutral substances didn't show humic-like fluorescence, while the fractions of HA-II, FA and building blocks usually had signatures of both humic-like and protein-like fluorescence. Humic substances generally contributed the largest proportion of dissolved organic carbon and nitrogen (DOC & DON) in effluents. Coagulation removed EfOM fractions following the order of biopolymers > HA subfraction > FA subfraction > building blocks, while little removal of protein-like fluorescence in HA-II and FA subfractions was detected. Anion exchange treatment could effectively reduce DOC and DON concentrations; the sequence of the treatment efficiency was humic substances > biopolymers > building blocks. Increasing O3 doses caused DOC and DON of EfOM to be gradually transformed from large AMW fractions into small AMW fractions, while chromophores and fluorophores in HA subfractions were relatively more refractory than those in the other fractions. Size exclusion chromatography with multiple detectors are suggested to be an informative technique for estimating treatability of EfOM by advanced wastewater treatment processes.

20.
Water Res ; 170: 115361, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816568

RESUMO

Phosphorus removal is an important issue in the field of water and wastewater treatment. In this study, a starch-based flocculant (St-CTA), as an assisting agent, was fed after the application of traditional inorganic precipitant of ferric chloride (FeCl3) to remove inorganic and organic phosphorus from their respective simulated turbid wastewaters. The effects of various influencing factors, including CTA content of St-CTA, dosage, initial pH, initial turbidity, and initial total phosphorus (TP), were investigated systematically. This modified chemical sedimentation process assisted by St-CTA not only showed high efficient in removing TP and turbidity but also evidently reduced the required dosage of FeCl3. This combination exhibited better efficiency in removing organic TP than in removing inorganic TP from water. The synergistic mechanisms of FeCl3 and St-CTA were discussed in detail by combination of apparent removal effects and floc properties. St-CTA exhibits strong charge neutralization and bridging flocculation effects and can thus efficiently aggregate and precipitate various phosphorus and iron complexes previously formed through chemical sedimentation, adsorption, and chelation. Besides, the validation of this combination usage was further confirmed by treating a real wastewater, and half of the required FeCl3 dosage and one third of the total cost were saved after addition of only 0.4 mg/L St-CTA when 90% TP and 95% turbidity were reduced. This study thus provided a novel technique for the diminution of TP and turbidity in turbid wastewater, considerable reduction of FeCl3 dosage and final cost, and lowering of secondary pollution risk.


Assuntos
Fósforo , Purificação da Água , Floculação , Amido , Água
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