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1.
Appl Opt ; 58(29): 8092-8100, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31674368

RESUMO

Laser-plane-based vision reconstruction is an important approach for 3D profile measurement and optical inspection. This study develops a 3D reconstruction method to measure the object with a flexible method. The active vision reconstruction includes an external camera and a 3D reference with an internal camera and laser projector. The 3D calibration object, the external camera, and the 3D reference constitute a closed loop. The internal camera, the 3D calibration object, and the 3D reference compose the other closed loop. The intrinsic invariants of the 3D reference with an internal camera and laser projector are determined by the two loops above. The benefit of the method is to cancel the position constraint for the active vision system with the cubic LED reference and the monocular external camera. Furthermore, as the external camera captures only the images of the 3D reference, the reconstruction system of the projector and the camera is flexible to observe the occlusion location on the measured object. The methods, including the calibration model and reconstruction model of the measurement system, are verified by experiments to demonstrate the potential applications.

2.
Genes (Basel) ; 10(11)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671638

RESUMO

Whereas a majority of monogenean flatworms are ectoparasitic, i.e., parasitize on external surfaces (mainly gills) of their fish hosts, Enterogyrus species (subfamily Ancyrocephalinae) are mesoparasitic, i.e., parasitize in the stomach of the host. As there are numerous drastic differences between these two environments (including lower oxygen availability), we hypothesized that this life-history innovation might have produced adaptive pressures on the energy metabolism, which is partially encoded by the mitochondrial genome (OXPHOS). To test this hypothesis, we sequenced mitochondrial genomes of two Ancyrocephalinae species: mesoparasitic E. malmbergi and ectoparasitic Ancyrocephalus mogurndae. The mitogenomic architecture of E. malmbergi is mostly standard for monogeneans, but that of A. mogurndae exhibits some unique features: missing trnL2 gene, very low AT content (60%), a non-canonical start codon of the nad2 gene, and exceptionally long tandem-repeats in the non-coding region (253 bp). Phylogenetic analyses produced paraphyletic Ancyrocephalinae (with embedded Dactylogyrinae), but with low support values. Selective pressure (PAML and HYPHY) and protein structure analyses all found evidence for adaptive evolution in cox2 and cox3 genes of the mesoparasitic E. malmbergi. These findings tentatively support our hypothesis of adaptive evolution driven by life-history innovations in the mitogenome of this species. However, as only one stomach-inhabiting mesoparasitic monogenean was available for this analysis, our findings should be corroborated on a larger number of mesoparasitic monogeneans and by physiological studies.

3.
J Chem Phys ; 151(13): 130902, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31594326

RESUMO

Solar water splitting promises a solution to challenges associated with the intermittent nature of solar energy. Of different implementations, photoelectrochemical water splitting, where one or more photoelectrodes harvest light and catalyze water splitting, represents a convenient platform to understand the governing principles of charge behaviors, especially at the light absorber|H2O interface. This Perspective recognizes and discusses the importance of the photoelectrode surface to solar water splitting performance. It presents discussions within the context of a prototypical water splitting material, Ta3N5, which has gained growing attention lately for its outstanding initial performance. Insights into the mechanisms by which Ta3N5 functions are presented, followed by examples of recent efforts to circumvent the issues that Ta3N5 decays rapidly under solar water splitting conditions. Our visions on the future directions of semiconductor-based solar water splitting will be presented at the end.

4.
Hum Mol Genet ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31625563

RESUMO

G4C2 repeat expansions in an intron of C9ORF72 cause the most common familial amyotrophic lateral sclerosis and frontotemporal dementia (collectively, C9ALS/FTD). Mechanisms and mediators of C9ALS/FTD pathogenesis remain poorly understood. C9orf72 and Smcr8 form a protein complex. Here we show that expression of Smcr8, like C9orf72, is reduced in C9ALS/FTD mouse models and patient tissues. Since Smcr8 is highly conserved between human and mouse, we evaluated the effects of Smcr8 downregulation in mice. Smcr8 knockout (KO) mice exhibited motor behavior deficits which resemble those of C9ALS/FTD mouse models, and displayed axonal swellings in their spinal cords and neuromuscular junctions. These deficits are caused by impaired autophagy-lysosomal functions due to disrupted axonal transport in mutant motor neurons. Consistent with its interaction with C9orf72 and their downregulation in patient tissues, Smcr8 deficiency exacerbated autophagy-lysosomal impairment in C9orf72 KO mice. The disease relevance of Smcr8 downregulation was reflected by exacerbated axonal swellings and gain of toxicity pathology arising from Smcr8 haploinsufficiency in a mouse model of C9ALS/FTD. Thus, our in vivo studies suggested that Smcr8 deficiency impairs axonal transport dependent autophagy-lysosomal function and exacerbates axonal degeneration and gain of toxicity in C9ALS/FTD mouse models.

5.
Rev Sci Instrum ; 90(9): 094703, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31575219

RESUMO

A sub-microsecond-range pulse generator based on an antiresonance network and transmission line transformer (TLT) is presented in this paper. The three-section antiresonance network (TSAN) and three-stage TLT take the roles of the pulse forming module and pulse voltage boosting module of this generator, respectively. The TSAN is applied to obtain a high quality and fixed flat top quasisquare pulse with fewer sections, and the three-stage TLT is used to obtain a higher voltage gain. Experimental results show that if the charging voltage of the TSAN is about 15.0 kV, the amplitude and pulse duration of the output voltage of the TSAN are about 7.2 kV and 400 ns, respectively, which correspond to the theoretical calculation results. Meanwhile, the amplitude of the output voltage of TLT is about 22.0 kV, so the voltage step-up ratio of the three-stage TLT is about 3.05. This generator displayed in the publication can transmit voltage pulses with low loss.

6.
Gen Comp Endocrinol ; 285: 113291, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31568758

RESUMO

Melanocortin-1 receptor (MC1R) has important roles in regulating pigmentation and inflammation. Melanocortin receptor accessory protein 2 (MRAP2) modulates trafficking, ligand binding, and signaling of mammalian melanocortin receptors. However, the effect of MRAP2 on fish MC1R has not been extensively studied. Herein, we cloned the orange-spotted grouper (Epinephelus coioides) mc1r, which had a 972 bp open reading frame encoding a putative protein of 323 amino acids. Grouper mc1r was mainly expressed in the brain, skin, testis, spleen, head kidney, and kidney. EcoMC1R showed high constitutive activities in both Gs-cAMP and ERK1/2 pathways, which could be differentially modulated by grouper MRAP2 (EcoMRAP2). Three agonists, including α-melanocyte-stimulating hormone (MSH), ß-MSH, and ACTH, could bind to EcoMC1R and dose-dependently increase intracellular cAMP production. EcoMRAP2 had no effect on the IC50 in binding assay or EC50 in cAMP assay; however, it dose-dependently decreased the cell surface expression and maximal response to the three agonists. EcoMRAP2 increased basal ERK1/2 activation but did not alter α-MSH-stimulated ERK1/2 activation. This study extends the knowledge base of fish MC1R pharmacology and its regulation by MRAP2.

7.
Neuroimmunomodulation ; : 1-17, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31665717

RESUMO

OBJECTIVES: Cortical neuron-released exosomes have been demonstrated to block inflammasome activation in the central nervous system. This study aimed to investigate whether cortical neuron-released exosomal microRNA-181c-3p (miR-181c-3p) affected ischemic brain injury (IBI). METHODS: An IBI rat model was established by middle cerebral artery occlusion (MCAO). Astrocytes collected from rats were exposed to exosomes derived from cortical neurons to investigate the effect of exosomes on chemokine (C-X-C motif) ligand 1 (CXCL1) expression and inflammatory response. Then, ectopic expression was induced in astrocytes treated with oxygen and glucose deprivation (OGD). RESULTS: CXCL1 was identified to be an upregulated gene in IBI by microarray-based gene expression profiling. Additionally, upregulation of CXCL1 and promoted inflammatory response was also found in MCAO rats. miR-181c-3p was downregulated in OGD-treated cortical neurons and exosomes derived from OGD-treated cortical neurons. Exosomes derived from OGD-treated cortical neurons decreased the expression of CXCL1 and inflammatory factors in astrocytes, and exosomes delivered miR-181c-3p to decrease CXCL1 expression in astrocytes. CXCL1 was a target gene of miR-181c-3p. Delivery with miR-181c-3p mimic and siRNA against CXCL1 (si-CXCL1) was shown to inhibit inflammation in astrocytes by downregulating CXCL1. CONCLUSION: Collectively, exosomal miR-181c-3p derived from cortical neurons exerts protective effects on neuroinflammation in astrocytes via downregulation of CXCL1 in an IBI rat model.

8.
Water Res ; 167: 115137, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585386

RESUMO

Two submerged anaerobic membrane bioreactors (AnMBRs) with and without powdered activated carbon (PAC) were studied to revisit the effect of PAC on membrane fouling performance by long-term operation when treating synthetic sewage. The results showed that PAC remained efficient for membrane fouling control after long-term operation (over 140 d), and it reduced the fouling rate at a hydraulic retention time of 8 h from 3.12 to 0.89 kPa/d. PAC mainly mitigated the membrane fouling by restraining the formation of a cake layer while generating a gel layer on the membrane surface, which was attributed to the PAC-induced microbial community change in mixed liquor and the membrane surface. Microbial community analysis indicated the genera Pseudomonas (26.5%) and Methanothrix (79.21%) were the predominant bacteria and archaea, respectively, in the gel layer, and this result is completely different from the presence of a high abundance of Levilinea (7.1%), Aminivibrio (4.9%) and Methanothrix (90.04%) in the cake layer on the membrane surface without PAC. The significant difference in the predominant microbes in the membrane surface layer was attributed to the reduced enrichment of Levilinea and Methanothrix with PAC addition.

9.
Eur Radiol ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31630235

RESUMO

PURPOSE: To identify the diagnostic performance of magnetic resonance (MR) imaging for patients with adnexal torsion and to develop a predictive model for necrosis related to torsion. METHODS: The institutional ethics committee approved this retrospective study. A total of 56 women with a preoperative pelvic MR scan and a surgical and pathologic diagnosis of adnexal torsion were enrolled from five institutions. Three radiologists reviewed the MR images independently. The kappa value of interrater agreement was assessed. Differences between patients treated with conservative surgery and adnexectomy were evaluated by univariate and multivariate logistic regression analyses. Receiver operating characteristic (ROC) curve analysis was used to assess the ability of the model to predict ovarian necrosis. RESULTS: Fifty-six patients were divided into the conservative surgery group (24/56, 42.9%) or the adnexectomy group (32/56, 57.1%) depending on the surgical outcomes. The radiographic features related to torsion were interpreted by three raters retrospectively with substantial interrater agreement (kappa > 0.60). Older reproductive age and pedicle hemorrhagic infarction were significantly associated with adnexectomy (p < 0.05). At multivariate analysis, pedicle hemorrhagic infarction (odds ratio = 10.476 [95% confidence interval 1.103, 99.504; p = 0.041]) was associated with adnexectomy. Using the predictive model (older reproductive age and pedicle hemorrhagic infarction), a receiver operating characteristic curve was generated with an area under the curve (AUC = 0.870 ± 0.049). CONCLUSION: The presence of pedicle hemorrhagic infarction and older reproductive age can predict necrosis of adnexal torsion and may be used to guide the optimal treatment strategy. KEY POINTS: • Pedicle hemorrhagic infarction and older reproductive age are predictors of necrosis in adnexal torsion in patients of reproductive age (AUC = 0.870 ± 0.049). • Cystic wall thickening, enlarged vascular pedicle, tubal thickening, and uterine deviation are associated with a high risk for adnexal torsion, occurring in more than half of the cases in this study. • MR findings are useful for the definitive diagnosis of adnexal torsion and for the prediction of adnexal necrosis.

10.
Nanomedicine ; : 102100, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31648038

RESUMO

Development of a sensitive, rapid and easy-to-use liquid biopsy method is of imperative clinical value for point-of-care caner diagnostics. Here, a label-free and modification-free nanotechnology based on surface-enhanced Raman spectroscopy (SERS) was employed for DNA analysis. Using the SERS signals of phosphate backbone as internal standard, quantitative detection for nucleobases was achieved even at single base level. The method combined with principal component analysis and linear discriminant analysis was further applied for real blood circulating DNA detection for the first time, and an ideal diagnostic sensitivity of 83.3% and specificity of 82.5% could be obtained for differentiating the nasopharyngeal cancer from the normal group, demonstrating promising potential as an alternative nanotechnology for nasopharyngeal cancer screening based on liquid biopsy.

11.
BMC Cardiovasc Disord ; 19(1): 223, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619168

RESUMO

BACKGROUND: Coronary heart disease (CHD) is a complex disease caused by multi-factors and a major threat to human health. Circular RNAs (circRNAs) have critical roles in various biological processes and diseases. This study explores the independent role of circRNAs and their interaction with environmental factors in CHD. METHODS: A case-control study was conducted from March 2015 to September 2017 in Fuzhou, China. A total of 585 CHD patients and 585 gender- and age-matched healthy controls were enrolled. Questionnaire survey, health examination and molecular biology laboratory testing were conducted. Microarray technology and quantitative real-time polymerase chain reaction (PCR) were used to profile the expression levels of circRNAs. The area under the curve (AUC) of the receiver operating characteristic (ROC) was used to determine the diagnostic cut-offs. Multivariate logistic regression and multiplicative analysis were used to analyse the effects of environmental factors and hsa_circ_0008507, hsa_circ_0001946, hsa_circ_0000284 and hsa_circ_0125589 on CHD. RESULTS: The expression profile of circRNAs showed that 3423 circRNAs were differentially expressed at P < 0.05, but none pass multiple testing correction. qRT-PCR further confirmed the expression levels of hsa_circ_0008507, hsa_circ_0001946 and hsa_circ_0000284 in peripheral blood leukocytes in CHD cases were higher than those in non-CHD subjects (All p < 0.05). Hsa_circ_0008507 (OR = 1.29; 95% CI: 1.11-1.50), hsa_circ_0001946 (OR = 1.20; 95% CI: 1.01-1.42) and hsa_circ_0000284 (OR = 2.05; 95% CI: 1.32-3.19) were independent risk factors for CHD after controlling other common environmental risk factors. The AUC for hsa_circ_0008507, hsa_circ_0001946 and hsa_circ_0000284 was 0.75, 0.71 and 0.68, respectively. Compared with non-smoking individuals with low hsa_circ_0008507 expression, the smokers with high hsa_circ_0008507 expression showed the highest magnitude of OR in CHD risk. Additionally, a statistically significant multiplicative interaction was found between hsa_circ_0008507 and smoking for CHD. CONCLUSIONS: Hsa_circ_0008507, hsa_circ_0001946 and hsa_circ_0000284 were closely related to the occurrence and development of CHD. The combination of smoking and high hsa_circ_0008507 expression causes the occurrence and development of CHD.

13.
World J Gastroenterol ; 25(31): 4468-4480, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31496625

RESUMO

BACKGROUND: Activation of hepatic stellate cells (HSCs) is a pivotal event in the onset and progression of liver fibrosis. Loss of microRNA-194 (miR-194) has been reported in activated HSCs, but the actual role of miR-194 in liver fibrosis remains uncertain. AIM: To explore the role and potential mechanism of miR-194-mediated regulation of liver fibrosis in vitro and in vivo. METHODS: The expression of miR-194 was examined in human fibrotic liver tissues, activated HSCs, and a carbon tetrachloride (CCl4) mouse model by qPCR. The effects of AKT2 regulation by miR-194 on the activation and proliferation of HSCs were assessed in vitro. For in vivo experiments, we reintroduced miR-194 in mice using a miR-194 agomir to investigate the functions of miR-194 in liver fibrosis. RESULTS: MiR-194 expression was notably lacking in activated HSCs from both humans and mice. Overexpression of miR-194 (OV-miR-194) inhibited α-smooth muscle actin (α-SMA) and type I collagen (Col I) expression and suppressed cell proliferation in HSCs by causing cell cycle arrest in G0/G1 phase. AKT2 was predicted to be a target of miR-194. Notably, the effects of miR-194 knockdown in HSCs were almost blocked by AKT2 deletion, indicating that miR-194 plays a role in HSCs via regulation of AKT2. Finally, miR-194 agomir treatment dramatically ameliorated liver fibrosis in CCl4-treated mice. CONCLUSION: We revealed that miR-194 plays a protective role by inhibiting the activation and proliferation of HSCs via AKT2 suppression. Our results further propose miR-194 as a potential therapeutic target for liver fibrosis.

14.
Ann Plast Surg ; 83(4S Suppl 1): S50-S54, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31513066

RESUMO

BACKGROUND: Current understanding of steroid treatments for keloids is in regards to modulation of inflammation, proliferation, and apoptosis, with no in vivo study on the latter. Using a nude mouse model, we investigated whether triamcinolone acetonide (TA) injections induce keloids regression through enhancing apoptosis. MATERIALS AND METHODS: Thirty-six keloid specimens (1 × 1 cm) were harvested from 6 patients and separated into sets of 2 from the same patient: no treatment and intralesional TA injection (0.4 mg/mL/kg) at 8 weeks of postimplantation. One set was implanted in each of 18 randomly selected nude mice, which were separated into 3 groups based on time of keloid harvesting after treatment: group A, 2 weeks; group B, 8 weeks; and group C, 14 weeks. Each group had 1 set of specimen from each patient. Histological staining was performed with hematoxylin and eosin stain. Immunohistochemistry staining was performed for human-prolyl 4-hydroxylase (hPH4) and caspase 3 protein, along with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. RESULTS: All keloid specimens survived, with no noted overgrowth. Hematoxylin and eosin staining revealed dense extracellular matrix and viable fibroblasts, and hPH4 immunohistochemistry revealed strong expression, demonstrating keloid viability. Caspase 3 protein and TUNEL expressions were significantly increased in the treatment versus control groups, demonstrating that TA injections induced apoptosis. CONCLUSIONS: Triamcinolone acetonide intralesional injections significantly increased apoptosis in keloids, represented by increased caspase 3 protein and TUNEL expressions, supporting that steroids suppress keloids in part owing to enhancement of apoptosis.

15.
Biosens Bioelectron ; 143: 111599, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476600

RESUMO

The reliable quantitative analysis of tumor biomarkers in circulating blood is crucial for cancer early screening, therapy monitoring and prognostic prediction. Herein, a novel biosensor combing surface-enhanced Raman spectroscopy (SERS) and surface molecularly imprinted polymer (SMIP) technology was developed for quantitative detection of carcinoembryonic antigen (CEA) that is closely related to several common cancers. Owing to the use of SMIP, recognition sites with high affinity to the target of interest can be well imprinted on the surface of SERS substrate, leading to a more stable and specific capture ability. In addition, two layers of core-shell nanoparticles were integrated to this SERS substrate to form highly efficient electromagnetic enhancement for SERS measurement via the generation of lots of "hot spot". Besides, a unique Raman reporter (CC) with silent Raman signals at 2024 cm-1 was capsulated in the nanoparticles to avoid the optical noises originating from endogenous molecules at fingerprint region (300-1800 cm-1). Meanwhile, we employed an internal standard molecular (CN) to real time correct the fluctuating signals of Raman reporter when performing the quantitative analysis. Due to these features, a limit of detection (LOD) of 0.064 pg mL-1 with the detection range of 0.1 pg mL-1 - 10 µg mL-1 can be achieved by this assay. Excitingly, this technology even showed wonderful performances for CEA detection in real blood from cancer patients, demonstrating great potential for biomarker-based cancer screening.

16.
Nat Commun ; 10(1): 3911, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477730

RESUMO

Chemical cross-linking of proteins coupled with mass spectrometry analysis (CXMS) is widely used to study protein-protein interactions (PPI), protein structures, and even protein dynamics. However, structural information provided by CXMS is still limited, partly because most CXMS experiments use lysine-lysine (K-K) cross-linkers. Although superb in selectivity and reactivity, they are ineffective for lysine deficient regions. Herein, we develop aromatic glyoxal cross-linkers (ArGOs) for arginine-arginine (R-R) cross-linking and the lysine-arginine (K-R) cross-linker KArGO. The R-R or K-R cross-links generated by ArGO or KArGO fit well with protein crystal structures and provide information not attainable by K-K cross-links. KArGO, in particular, is highly valuable for CXMS, with robust performance on a variety of samples including a kinase and two multi-protein complexes. In the case of the CNGP complex, KArGO cross-links covered as much of the PPI interface as R-R and K-K cross-links combined and improved the accuracy of Rosetta docking substantially.

17.
J Pathol ; 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31531867

RESUMO

Molecular signalling mediated by the phosphatidylinositol-3-kinase (PI3K)-Akt axis is a key regulator of cellular functions. Importantly, alteration of the PI3K--Akt signalling underlies the development of different human diseases, thus prompting the investigation of the pathway as a molecular target for pharmacologic intervention. In this regard, recent studies showed that small molecule inhibitors of PI3K, the upstream regulator of the pathway, reduced the development of inflammation during acute pancreatitis, a highly debilitating and potentially lethal disease. Here we investigated whether a specific reduction of Akt activity, by using either pharmacologic Akt inhibition, or genetic inactivation of the Akt1 isoform selectively in pancreatic acinar cells, is effective in ameliorating the onset and progression of the disease. We discovered that systemic reduction of Akt activity did not protect the pancreas from initial damage and only transiently delayed leukocyte recruitment. However, reduction of Akt activity decreased acinar proliferation and exacerbated ADM formation, two critical events in the progression of pancreatitis. These phenotypes were recapitulated upon conditional inactivation of Akt1 in acinar cells, which resulted in reduced expression of 4E-BP1, a multifunctional protein of key importance in cell proliferation and metaplasia formation. Collectively, our results highlight the critical role played by Akt1 during the development of acute pancreatitis in the control of acinar cell proliferation and ADM formation. In addition, these results harbour important translational implications as they raise the concern that inhibitors of PI3K-Akt signalling pathways may negatively affect the regeneration of the pancreas. Finally, this work provides the basis for further investigating the potential of Akt1 activators to boost pancreatic regeneration following inflammatory insults. This article is protected by copyright. All rights reserved.

18.
Chembiochem ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31476106

RESUMO

The absolute configuration of fusaterpenol (GJ1012E) was revised by the enantioselective deuteration strategy. A bifunctional enzyme with a terpene synthase and a prenyltransferase domain from Aspergillus brasiliensis was characterised as variediene synthase and the absolute configuration of its product was elucidated. The uniform absolute configurations of these and structurally related di- and sesterterpenes together with a common stereochemical course for the geminal methyl groups of GGPP unravel a similar conformational fold of the substrate in the active sites of the terpene synthases. For variediene a thermal reaction observed during GC/MS analysis was studied in detail for which a surprising mechanism was uncovered.

19.
J Hazard Mater ; 383: 121172, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31522062

RESUMO

In this study, magnetic ordered mesoporous Fe/Ce bimetal oxides (OMICs) were successfully synthesized via the modified sol-gel-based inverse micelle method. The textural/structure properties, surface chemistry and adsorption behavior of OMICs could be easily adjusted by using the calcination temperature. The sintering of samples would decrease the surface area, while expand the pore and crystallite size, which resulted in the formation of highly ordered inner-connected structure. Compared with pure mesoporous iron oxides (MI) and mesoporous cerium oxides (MC), this ordered mesoporous iron-cerium bimetal oxides (OMIC-3, 450 °C) exhibited remarkable arsenic adsorption performance. The maximum adsorption capacities of As(III) and As(V) for OMIC-3 were 281.34 and 216.72 mg/g, respectively, and both As(III)/As(V) adsorption kinetics were well described by the pseudo-second order. The ionic strength and coexisting ions (except SiO32- and PO43-) did not affect arsenic removal, while humic acid (HA) significantly influenced on the arsenic removal even at a lower concentration. The adsorption mechanism study revealed that both the surface charge and surface M-OH groups of OMIC-3 were played the key roles in arsenic removal. The reusable property suggested that this magnetic OMIC-3 was a promising excellent adsorbent for decontamination of arsenic-polluted (especially As(III)-polluted) wastewater.

20.
Toxicon ; 170: 51-59, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31526809

RESUMO

Cu2+ and Zn2+, two ubiquitous metals in water environments, can widely trigger algae blooms at favourable environmental conditions. This paper elucidates the roles of Cu2+ and Zn2+ in the proliferation of Microcystis aeruginosa (M. aeruginosa) and synthesis of Microcystins (MCs). Findings indicate significant influences of increasing Cu2+ and Zn2+ concentrations on cell proliferation at limited available phosphorus concentrations of less than 0.1 mg/L. By contrast, Cu2+ and Zn2+ notably affected MCs production at all the inoculated phosphorus concentrations. The critical concentrations of 1 µg/L and 5 µg/L for Cu2+ and Zn2+, respectively, are determined to trigger rapid cell proliferation and MCs production. Furthermore, the impacts of Cu2+ and Zn2+ on nitrogen absorption and, subsequently, on amino acids (AAs) formation in cells, is likely key in MCs synthesis. The two AAs Alanine (Ala) and glutamic acid (Glu) demonstrate the most notable variations with the concentrations of Cu2+ & Zn2+.

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