Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 123
Filter
Add more filters

Country/Region as subject
Affiliation country
Publication year range
1.
Genomics ; 116(1): 110755, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38061481

ABSTRACT

Acute lung injury (ALI) is a serious illness that develops suddenly, progresses rapidly, has a poor treatment response and a high mortality rate. Studies have found that circular RNAs (circRNA) play a critical role in several diseases, but their role in ALI remains unclear. The aim of this study was to identify circRNAs that are associated with ALI and investigate their potential molecular mechanisms. A comparison of lung circRNA and microRNA expression profiles in mice with ALI and controls was performed by RNA-sequencing. A bioinformatic analysis was conducted to identify differentially expressed (DE) RNAs, to construct competitive endogenous RNA (ceRNA) networks, and to analyze their function and pathways. Then, a protein-protein interaction (PPI) network was generated by the Search Tool for the Retrieval of Interacting Genes database, and hub genes were identified using Cytoscape. Furthermore, a key ceRNA subnetwork was constructed based on these hub genes. Overall, we found 239 DE circRNAs and 42 DE microRNAs in ALI mice compared to controls. Additionally, the molecular mechanism of ALI was further understood by building ceRNA networks based on these DE genes. ALI-induced circRNAs are mostly function in the inflammatory response and metabolic processes. Moreover, DE circRNAs are primarily involved in the nuclear factor (NF)-kappa B and PI3K-Akt signaling pathways. Seven hub genes were derived from the PPI network of 191 genes, followed by the construction of circRNA-miRNA-hub gene subnetworks. In this study, circRNA profiles are remarkably changed in mice with LPS-triggered ALI, and their potential contribution to the disease is revealed.


Subject(s)
Acute Lung Injury , MicroRNAs , Mice , Animals , RNA, Circular/genetics , Lipopolysaccharides/toxicity , RNA-Seq , RNA, Messenger/metabolism , Phosphatidylinositol 3-Kinases/genetics , Gene Expression Profiling , MicroRNAs/metabolism , Acute Lung Injury/chemically induced , Acute Lung Injury/genetics , Gene Regulatory Networks
2.
BMC Genomics ; 25(1): 320, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38549066

ABSTRACT

BACKGROUND: Stigma exsertion is an essential agricultural trait that can promote cross-pollination to improve hybrid seed production efficiency. However, the molecular mechanism controlling stigma exsertion remains unknown. RESULTS: In this study, the Nicotiana tabacum cv. K326 and its two homonuclear-heteroplasmic lines, MSK326 (male-sterile) and MSK326SE (male-sterile and stigma exserted), were used to investigate the mechanism of tobacco stigma exsertion. A comparison of the flowers between the three lines showed that the stigma exsertion of MSK326SE was mainly due to corolla shortening. Therefore, the corollas of the three lines were sampled and presented for RNA-seq analysis, which found 338 candidate genes that may cause corolla shortening. These genes were equally expressed in K326 and MSK326, but differentially expressed in MSK326SE. Among these 338 genes, 15 were involved in hormone synthesis or signal transduction pathways. Consistently, the content of auxin, dihydrozeatin, gibberellin, and jasmonic acid was significantly decreased in the MSK326SE corolla, whereas abscisic acid levels were significantly increased. Additionally, seven genes involved in cell division, cell cycle, or cell expansion were identified. Protein-protein interaction network analysis identified 45 nodes and 79 protein interactions, and the largest module contained 20 nodes and 52 protein interactions, mainly involved in the hormone signal transduction and pathogen defensive pathways. Furthermore, a putative hub gene coding a serine/threonine-protein kinase was identified for the network. CONCLUSIONS: Our results suggest that hormones may play a key role in regulating tobacco stigma exsertion induced by corolla shortening.


Subject(s)
Nicotiana , Transcriptome , Nicotiana/genetics , Disclosure , Indoleacetic Acids/metabolism , Hormones/metabolism , Flowers/metabolism
3.
J Environ Manage ; 336: 117653, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36893542

ABSTRACT

To evaluate the long-term climate change impacts on groundwater fluctuations of the Ardabil plain, Iran, a groundwater level (GWL) modeling was proposed in this study. Accordingly, the outputs of Global Climate Models (GCMs) under the sixth report of Coupled Model Intercomparison Project (CMIP6) and future scenario of the Shared Socioeconomic Pathway 5-8.5 (SSP5-8.5), were used as climate change forcing to the Machine learning (ML) models. The GCM data were first downscaled and projected for the future via Artificial Neural Networks (ANNs). Based on the results, compared to 2014 (the last year of the base period), the mean annual temperature may increase by 0.8 °C per decade until 2100. On the other hand, the mean precipitation may decrease by about 8% compared to the base period. Then, the centroid wells of clusters were modeled by Feedforward Neural Network (FFNN), examining different input combination sets to simulate both autoregressive and non-autoregressive models. Since each of the ML models can extract different kinds of information from a dataset, after finding the dominant input set via FFNN, GWL time series were modeled via various ML methods. The modeling results indicated that the ensemble of shallow ML models could lead to a 6% more accurate outcome than the individual shallow ML models, and 4% than the deep learning models. Also, the simulation results for future GWLs illustrated that temperature can impact groundwater oscillations directly, whereas precipitation may not have uniform impacts on the GWLs. The uncertainty evolving in the modeling process was quantified and observed to be in acceptable range. Modeling results showed that the main reason for the declining GWL in the Ardabil plain could be primarily linked to the excessive exploitation of the water table, while climate change impact could be also notable.


Subject(s)
Climate Change , Groundwater , Computer Simulation , Neural Networks, Computer , Iran
4.
J Prosthet Dent ; 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37940472

ABSTRACT

STATEMENT OF PROBLEM: Tooth preparation is a fundamental aspect of prosthodontics and serves as a focal point in preclinical courses. Conventional pedagogy relies heavily on the expertise of instructors, whereas digital technology has the potential to offer instantaneous feedback. The efficacy of a digital assessment system in comparison with traditional teaching methods remains uncertain. PURPOSE: The purpose of this study was to compare the training effects of traditional assessment and digital evaluation on tooth preparations for the metal-ceramic crowns performed by preclinical students on the convergence angle and tooth reduction. MATERIAL AND METHODS: A total of 40 predoctoral students were randomly divided into the digital group and the traditional group to complete tooth preparation for a metal-ceramic crown on a left mandibular first molar. Students in the traditional group were taught by an experienced instructor, while the digital group students were trained by an objective digital assessment system without instructor guidance. Each student completed the tooth preparation in 20 min, received feedback according to the respective training methods, and later prepared another tooth. In this way, all students completed 4 tooth preparations in 2 weeks. All preparations were evaluated by an optical scanner. Parameters for comparing the digital group with the traditional group were the convergence angle and reduction at different stages. Questionnaires on the digital training system were answered by the students of the digital group. The t tests or Wilcoxon signed rank tests and chi-squared tests were used to analyze the differences between the 2 groups (α=.01). RESULTS: A decreasing trend in convergence angle was seen in both groups, but the 2 groups were statistically similar (P>.01). After training, a decreasing trend was seen in under-reduction and overreduction on 5 surfaces in the digital group. Conversely, in the traditional group, a noteworthy increase was seen in under-reduction on the distal surface (P=.002). Nevertheless, no significant difference was found between the 2 groups (P>.01). According to the results of the questionnaire, over 80% of the students had a positive attitude toward the digital assessment system, and more than 80% of the students expressed their interest in the digital assessment system for tooth preparation training. CONCLUSIONS: Traditional teaching and digital feedback provided similar training effects to improve the quality of tooth preparations for preclinical dental students.

5.
Environ Sci Technol ; 56(18): 13314-13326, 2022 09 20.
Article in English | MEDLINE | ID: mdl-36041071

ABSTRACT

Fe0 is a promising electron donor for autotrophic denitrification in the simultaneous removal of nitrate and phosphorus in low C/N wastewater. However, P removal may inevitably inhibit bio-denitrification. It has not been well recognized and led to an overdose of iron materials. This study employed carbon-coated zerovalent iron (Fe0@C) to support autotrophic denitrification to mitigate the inhibition effects of P removal and enhance both N and P removal. The critical role of the carbon shell in Fe0@C was to block the direct contact between Fe0 and P and NO3--N, to maintain the Fe0 activity. Besides, P inhibited the chemical reduction of NO3--N by competing for Fe0 active sites. This indirectly boosted H2 generation and promoted bio-denitrification. P removal displayed negligible effects on microbial species but indirectly enhanced the nitrogen metabolic activities because of promoted H2 in Fe0@C-based autotrophic denitrification. Bio-denitrification, in turn, strengthened Fe-P co-precipitation by promoting the formation of ferric hydroxide as a secondary adsorbent for P removal. This study demonstrated an efficient method for simultaneous N and P removal in autotrophic denitrification and revealed the synergistic interactions among N and P removal processes.


Subject(s)
Carbon , Denitrification , Autotrophic Processes , Bioreactors , Iron , Nitrates , Nitrogen , Phosphorus , Wastewater
6.
Environ Res ; 204(Pt A): 111903, 2022 03.
Article in English | MEDLINE | ID: mdl-34454932

ABSTRACT

The bacteria (including pathogenic bacteria) attached to road deposited sediments (RDS) may interrelate with the microbe in the atmosphere, soil and water through resuspension and wash-off, and is of great significance to human and ecological health. However, the characteristics of bacterial communities with different time scale on RDS were unknown to dates. Climate change prolonged the dry days between rain events in many areas, making the varied trend of bacterial communities might be more significant in short term. This study revealed the characteristics of bacterial communities on RDS in urban and suburban areas through seasonal and daily scale. The correlations between other factors (land use, particle size, and chemical components) and the bacterial communities were also analyzed. It was found that the season showed a higher association with the bacterial community diversity than land use and particle size in urban areas. The bacterial community diversity increased substantially throughout the short-term study period (41 days) and the variation of dominant bacteria could be fitted by quadratic function in suburbs. In addition, urbanization notably increased the bacterial community diversity, while the potential pathogenic bacteria were more abundant in the suburban areas, coarse RDS (>75 µm), and in spring. The chemical components on RDS showed special correlations with the relative abundance of dominant bacteria. The research findings would fill the knowledge gap on RDS bacterial communities and be helpful for the future research on the assembly process of bacterial communities.


Subject(s)
Environmental Monitoring , Geologic Sediments , Bacteria , Humans , Rain , Seasons
7.
J Environ Manage ; 323: 116187, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36261960

ABSTRACT

The accurate estimation of coastal water quality parameters (WQPs) is crucial for decision-makers to manage water resources. Although various machine learning (ML) models have been developed for coastal water quality estimation using remote sensing data, the performance of these models has significant uncertainties when applied to regional scales. To address this issue, an ensemble ML-based model was developed in this study. The ensemble ML model was applied to estimate chlorophyll-a (Chla), turbidity, and dissolved oxygen (DO) based on Sentinel-2 satellite images in Shenzhen Bay, China. The optimal input features for each WQP were selected from eight spectral bands and seven spectral indices. A local explanation strategy termed Shapley Additive Explanations (SHAP) was employed to quantify contributions of each feature to model outputs. In addition, the impacts of three climate factors on the variation of each WQP were analyzed. The results suggested that the ensemble ML models have satisfied performance for Chla (errors = 1.7%), turbidity (errors = 1.5%) and DO estimation (errors = 0.02%). Band 3 (B3) has the highest positive contribution to Chla estimation, while Band Ration Index2 (BR2) has the highest negative contribution to turbidity estimation, and Band 7 (B7) has the highest positive contribution to DO estimation. The spatial patterns of the three WQPs revealed that the water quality deterioration in Shenzhen Bay was mainly influenced by input of terrestrial pollutants from the estuary. Correlation analysis demonstrated that air temperature (Temp) and average air pressure (AAP) exhibited the closest relationship with Chla. DO showed the strongest negative correlation with Temp, while turbidity was not sensitive to Temp, average wind speed (AWS), and AAP. Overall, the ensemble ML model proposed in this study provides an accurate and practical method for long-term Chla, turbidity, and DO estimation in coastal waters.


Subject(s)
Environmental Pollutants , Water Quality , Remote Sensing Technology , Environmental Monitoring/methods , Chlorophyll , Machine Learning , Oxygen
8.
J Environ Manage ; 323: 116234, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36261962

ABSTRACT

Due to the mass production and daily use of plastic products, the potential toxicity of microplastics to the water environment has attracted worldwide attention. In this work, the effect of typical microplastics (PET) on the performance of activated sludge from membrane bioreactors (MBR) was evaluated. The impacts on biological removal efficiency were unconspicuous with continuous dosing of 60 particles/L. However, further investigations revealed that PET particle accumulation caused adverse impacts on settleability and dewaterability. The SVI value increased from 53.3 ml/g MLSS to 69.9 ml/g MLSS and the CST in the PET reactor increased by 22%. Nevertheless, hydrophobicity was reduced by 49.2%. Mechanism studies exposed that the PET microplastics accumulation improved extracellular polymeric substances (EPS) from 116.96 mg/L to 138.70 mg/L and caused cell membrane damage. The abundance and diversity of microbial community reduced in activated sludge in PET reactor compared with control reactor. These phenomena revealed a possible hypothesis that the microplastic particles increased EPS and cytotoxicity of activated sludge. However, the rate of transmembrane pressure (TMP) build-up was significantly mitigated in PET-MBR compared to that in a control-MBR (1.27 folds), which attributes that physical scour of particles may still alleviate membrane contamination in MBR.


Subject(s)
Microplastics , Sewage , Microplastics/toxicity , Plastics , Polyethylene Terephthalates , Membranes, Artificial , Bioreactors , Water
9.
J Environ Manage ; 302(Pt A): 113995, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34700080

ABSTRACT

Microplastics (MPs) have recently attracted much attention due to their widespread distribution in the aquatic environment. Microplastics can act as a vector of heavy metals in the aquatic environment, causing a potential threat to aquatic organisms and human health. This review mainly summarized the occurrence of microplastics in the aquatic environment and their interaction with heavy metals. Then, we considered the adsorption mechanisms of MPs and heavy metals, and further critically discussed the effects of microplastics properties and environmental factors (e.g., pH, DOM, and salinity) on the adsorption of heavy metals. Finally, the potential risks of combined exposure of MPs and heavy metals to aquatic biota were briefly evaluated. This work aims to provide a theoretical summary of the interaction between MPs and heavy metals, and is expected to serve as a reference for the accurate assessment of their potential risks in future studies.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Adsorption , Humans , Metals, Heavy/toxicity , Microplastics , Plastics , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
10.
Water Sci Technol ; 85(3): 900-913, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35166709

ABSTRACT

The enzyme-linked immunosorbent assay (ELISA), as a universal method for the determination of Microcystins, is of great significance for the rapid detection of Microcystins pollution. This study aimed to propose a simplified validation method for Microcystins ELISA kit by summarizing related documents and guidelines. After summarizing and clarifying from 20 validation parameters, 11 parameters were selected to simplify the validation of Microcystins ELISA kit. In addition, the acceptable range and validation details of each parameter were analyzed. The results indicated that the coefficient of determination of the Microcystin-LR standard curve was higher than 0.99. The concentration of quality control samples was within control limits. The accuracy of spiked and proficient samples was within 70%-130%. The variability of intra-assay, inter-assay, and reproducibility was less than 11, 15 and 21%, respectively. The LOD and LLOQ were 0.002 µg/L and 0.05 µg/L, respectively. When the concentration of Microcystins exceeded 5 µg/L, it was recommended to dilute the samples to the working range before detection. The specificity was estimated with seven Microcystin analogues and three amino acids, indicating that the cross-reactivity was less than 30%. These results revealed that the ELISA kit was satisfactory for detecting Microcystins in water.


Subject(s)
Microcystins , Water , Enzyme-Linked Immunosorbent Assay , Reproducibility of Results
11.
BMC Endocr Disord ; 21(1): 88, 2021 Apr 29.
Article in English | MEDLINE | ID: mdl-33926416

ABSTRACT

BACKGROUND: B lymphocyte activating factor (BAFF) is a growth factor regulating B lymphocytes survival and maturation. Serum BAFF levels were elevated in patients affected with autoimmune thyroid diseases (AITD), including Graves' disease (GD) and Hashimoto's thyroiditis (HT). The aim of this study is to explore the association of expression levels of BAFF and its receptors with AITD. METHODS: Fifty-two GD patients, 39 Hashimoto's thyroiditis (HT) patients and 23 healthy controls (HC) were recruited in this study. Serum BAFF levels were measured by ELISA. Expression of BAFF receptors, including BAFF receptor 3 (BR3) and transmembrane activator and calcium-modulating and cyclophilin ligand interactor (TACI), on B lymphocytes were analyzed by flowcytometry. Effects of steroids on serum BAFF levels and expression of BR3 and TACI were also observed in 10 patients with Graves' orbitopathy (GO) receiving steroids therapy. RESULTS: Serum BAFF levels were significantly elevated from 0.93 ± 0.24 ng/ml in HC to 1.18 ± 0.33 ng/ml in GD (P = 0.0027) and 1.02 ± 0.24 ng/ml in HT (P = 0.0331). BR3 expression on peripheral B lymphocytes were elevated in GD (mean MFI: 4.52 ± 2.06 in GD vs. 3.00 ± 0.87 in HC, P = 0.0015), while TACI expression on peripheral B lymphocytes were decreased in GD without significance (mean MFI: 7.96 ± 4.06 in GD vs. 9.10 ± 3.37 in HC, P = 0.1285). Expression of BR3 and TACI was not changed significantly in HT patients. Steroids significantly suppressed serum BAFF concentrations (from 1.18 ± 0.27 ng/ml to 0.97 ± 0.10 ng/ml, P = 0.0364) and BR3 expression in GO patients (mean MFI from 6.26 ± 4.91 to 4.05 ± 1.58, P = 0.0083). CONCLUSIONS: Altered expression of BAFF and its receptor may mediate the autoimmunity in GD. Restoring the normal expression profile of receptors for BAFF could be a new strategy to treat GD.


Subject(s)
B-Cell Activation Factor Receptor/metabolism , B-Lymphocytes/metabolism , Graves Disease/blood , Adult , Autoimmunity/immunology , B-Cell Activating Factor/metabolism , Case-Control Studies , China , Female , Graves Disease/immunology , Graves Disease/metabolism , Graves Ophthalmopathy/blood , Graves Ophthalmopathy/immunology , Graves Ophthalmopathy/metabolism , Hashimoto Disease/blood , Hashimoto Disease/immunology , Hashimoto Disease/metabolism , Humans , Male , Middle Aged , Young Adult
12.
Environ Sci Technol ; 54(12): 7611-7618, 2020 06 16.
Article in English | MEDLINE | ID: mdl-32396342

ABSTRACT

The aqueous-aqueous membrane extractive process is an ideal approach to remove recalcitrant organics from highly saline and harsh wastewater. However, it is still challenging to develop highly efficient membranes for the extractive process. In this work, three-tiered polydimethylsiloxane (PDMS)/polyvinylidene fluoride (PVDF) nanofiber/nonwoven fabric composite membranes were prepared by electrospinning and electrospray printing for the first time. An ultrathin and defect-free PDMS selective layer was fabricated on the surface of a PVDF/nonwoven fabric nanofibrous substrate by electrospray printing. Meanwhile, the thicknesses of the PDMS selective layer were able to be finely controlled by electrospray printing. The novel three-tiered composite membrane #N3-1 with the thinnest PDMS layer (3.0 ± 0.4 µm) and a thin and porous supporting layer showed an exceptionally high k0 of 37.9 ± 2.8 × 10-7 m/s and an excellent salt rejection above 99.95% over a 105 h continuous operation. Moreover, #N3-1 exhibited outstanding k0 at feed pH of 2 and 11 over 100 h without loss of salt rejection. In addition, the effects of the nonwoven fabric supporting layer on the phenol mass transfer coefficient (k0, m/s) of resultant extractive membranes were also studied symmetrically. A thin and porous nonwoven supporting layer #N3 was capable of improving the k0 of resultant composite membrane significantly.


Subject(s)
Nanofibers , Phenol , Membranes, Artificial , Porosity , Wastewater
13.
Med Sci Monit ; 26: e924457, 2020 Jun 19.
Article in English | MEDLINE | ID: mdl-32559181

ABSTRACT

BACKGROUND Early interventions have been believed to have a positive influence on the neurodevelopment of infants. Our Child Health Center has carried out parenting training for parents of infants for several years to promote the neurobehavioral development of infants at an early stage. MATERIAL AND METHODS We enrolled 117 families with term infants age 0-3 months who had completed a parenting training class at the Child Health Center of the Department of Pediatrics, the Third Xiangya Hospital. Parenting training included 4 parts: nursing, intelligence, social contact, and physical ability. A nurse practitioner demonstrated procedures to parents, who then performed them at home for 1 month. The Neonatal Behavioral Neurological Assessment (NBNA) was used to evaluate infants before and 1 month after parenting training. RESULTS In the comparative analysis before and after parenting training, there was a significant increase in the NBNA scores. For the infants whose parents received parenting training, the NBNA scores in total score (33.74±0.19 before parenting training vs. 36.69±0.20 after 1 month), neonatal behavioral capacity (10.19±0.14 before parenting training vs. 11.26±0.10 after 1 month), passive muscle tension (7.28±0.07 before parenting training vs. 7.82±0.04 after 1 month), and initiative muscle tension (4.29±0.08 before the parenting training vs. 5.61±0.13 after 1 month) were significantly higher one month before (P<0.01). CONCLUSIONS Term infant neurobehavior was associated with participation in parenting training, suggesting that these practices of parenting training support better early neurobehavioral development of infants.


Subject(s)
Child Development , Infant Behavior , Muscle Tonus , Parents/education , Reflex , Early Intervention, Educational , Female , Humans , Infant , Infant, Newborn , Male , Parenting , Social Behavior
14.
Ecotoxicol Environ Saf ; 189: 109914, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31761551

ABSTRACT

Recently, a large quantity of carbon nanotubes (CNTs) enters the environment due to the increasing production and applications. More and more researches are focused on the fate and possible ecological risks of CNTs. Some literatures summarized the effects of CNTs on the chemical behavior and fate of pollutants. However, little reviewed the effects of CNTs on the biodegradation of pollutants. In general, the effects of CNTs on the biodegradation of pollutants and the related mechanisms were summarized in this review. CNTs have positive or negative effects on the biodegradation of contaminants by affecting the functional microorganisms, enzymes and the bioavailability of pollutants. CNTs may affect the microbial growth, activity, biomass, community composition, diversity and the activity of enzymes. The decrease of the bioavailability of pollutants due to the sorption on CNTs also causes the reduction of the biodegradation of contaminants. In addition, the roles of CNTs are controlled by multiple mechanisms, which are divided into three aspects i.e., properties of CNTs, environment condition, and microorganisms themself. The better understanding of the fate of CNTs and their impacts on the biochemical process in the environment is conducive to determine the release of CNTs into the environment.


Subject(s)
Biodegradation, Environmental , Environmental Pollutants , Nanotubes, Carbon , Biomass
15.
Molecules ; 25(17)2020 Aug 19.
Article in English | MEDLINE | ID: mdl-32824998

ABSTRACT

Azobenzene (AB) units were successfully introduced into poly(1,6-heptadiyne)s in order to ensure smooth synthesis of double- and single-stranded poly(1,6-heptadiyne)s (P1 and P2) and simultaneously realize the self-assembly by Grubbs-III catalyst-mediated metathesis cyclopolymerization (CP) of AB-functionalized bis(1,6-heptadiyne) and 1,6-heptadiyne monomers (M1 and M2). Monomers and polymers were characterized by 1H NMR, mass spectroscopy, and GPC techniques. The double-stranded poly(1,6-heptadiyne)s exhibited a large scale of ordered ladder nanostructure. This result was attributed to the π-π attractions between end groups along the longitudinal axis of the polymers and van der Waals interactions between the neighboring polymeric backbones. While the Azo chromophore connected in the side chain of P2 induced conformation of micelles nanostructure during the CP process without any post-treatment. Furthermore, the photoisomerization of Azo units had an obviously different regulatory effect on the conjugated degree of the polymer backbone, especially for the single-stranded P2, which was attributed to the structural differences and the interaction between AB chromophores in the polymers.


Subject(s)
Azo Compounds/chemistry , Nanostructures/chemistry , Polymerization , Polymers/chemistry , Catalysis , Magnetic Resonance Spectroscopy , Molecular Conformation
16.
Small ; 15(23): e1901008, 2019 06.
Article in English | MEDLINE | ID: mdl-30972930

ABSTRACT

Highly active photocatalysts driving chemical reactions are of paramount importance toward renewable energy substitutes and environmental protection. As a fascinating Aurivillius phase material, Bi2 MoO6 has been the hotspot in photocatalytic applications due to its visible light absorption, nontoxicity, low cost, and high chemical durability. However, pure Bi2 MoO6 suffers from low efficiency in separating photogenerated carriers, small surface area, and poor quantum yield, resulting in low photocatalytic activity. Various strategies, such as morphology control, doping/defect-introduction, metal deposition, semiconductor combination, and surface modification with conjugative π structures, have been systematically explored to improve the photocatalytic activity of Bi2 MoO6 . To accelerate further developments of Bi2 MoO6 in the field of photocatalysis, this comprehensive Review endeavors to summarize recent research progress for the construction of highly efficient Bi2 MoO6 -based photocatalysts. Furthermore, benefiting from the enhanced photocatalytic activity of Bi2 MoO6 -based materials, various photocatalytic applications including water splitting, pollutant removal, and disinfection of bacteria, were introduced and critically reviewed. Finally, the current challenges and prospects of Bi2 MoO6 are pointed out. This comprehensive Review is expected to consolidate the existing fundamental theories of photocatalysis and pave a novel avenue to rationally design highly efficient Bi2 MoO6 -based photocatalysts for environmental pollution control and green energy development.

17.
Biomacromolecules ; 20(5): 2058-2067, 2019 05 13.
Article in English | MEDLINE | ID: mdl-31009574

ABSTRACT

The purpose of this study was to fabricate a low-immunogenicity fish collagen (FC) and bioactive nanohydroxyapatite (n-HA) enhanced poly(lactide- co-glycolide) (PLGA) nanofibrous membrane for guided bone regeneration (GBR) via electrospinning. The physicochemical properties and morphology study revealed that FC and n-HA particles were homogeneously dispersed in the PLGA fibrous matrix. Notably, the formation of enhanced polymeric chain network due to the interaction between FC and PLGA significantly improved the tensile strength of the PLGA membrane. The incorporation of FC altered the degradation behavior of fibers and accelerated the degradation rate of the PLGA-based membranes. Moreover, the membranes exhibited favorable cytocompatibility with bone mesenchymal stem cells (BMSCs) and human gingiva fibroblasts (HGF) cells. More importantly, the optimized membrane satisfied the requirements of the 'Biological evaluation of medical devices' during the incipient biosafety evaluation. All the results indicate that this composite fibrous membrane exhibits significant potential for guided bone or tissue regeneration.


Subject(s)
Bone Regeneration , Collagen/chemistry , Durapatite/chemistry , Membranes, Artificial , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Tissue Scaffolds/chemistry , Biocompatible Materials/chemistry , Fibroblasts , Fish Proteins/chemistry , Humans , Mesenchymal Stem Cells
19.
Biotechnol Lett ; 40(7): 1067-1075, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29736595

ABSTRACT

OBJECTIVE: A modified method was used for cell entrapped beads (CEBs) preparation and two aeration intensities (low and high aeration intensity) was supplied as factors to investigate the change of quorum quenching performance for membrane biofouling in membrane bioreactor (MBR). RESULTS: Dehydrogenase activity and growth trend of activated sludge were improved at high aeration intensity. Compared with C-MBR (with vacant beads), QQ-MBR (with CEBs) had more stable quorum quenching activity and longer application time at high aeration intensity, in which the proteins and polysaccharides were reduced by 15 and 20%, respectively. The difference of EPS concentration in mixed liquor was attributed to the protein concentration controlled by quorum quenching bacteria, meanwhile sufficient organics was necessary to maintain the process. CONCLUSIONS: The better settleability, greater stability and relatively lower hydrophobicity of activated sludge properties was achieved with quorum quenching. The scouring effect of CEBs was promoted at high aeration intensity, further controlling the membrane biofouling.


Subject(s)
Biofouling/prevention & control , Bioreactors/microbiology , Membranes/microbiology , Quorum Sensing , Sewage/microbiology , Polysaccharides/analysis , Proteins/analysis
20.
Opt Express ; 24(7): 7299-318, 2016 Apr 04.
Article in English | MEDLINE | ID: mdl-27137020

ABSTRACT

Considering the measuring range limitation of a single sensor system, multi-sensor system has become essential in obtaining complete image information of the object in the field of 3D image reconstruction. However, for the traditional multi-sensors worked independently in its system, there was some point in calibrating each sensor system separately. And the calibration between all single sensor systems was complicated and required a long time. In this paper, we present a flexible 3D reconstruction method based on phase-matching in multi-sensor system. While calibrating each sensor, it realizes the data registration of multi-sensor system in a unified coordinate system simultaneously. After all sensors are calibrated, the whole 3D image data directly exist in the unified coordinate system, and there is no need to calibrate the positions between sensors any more. Experimental results prove that the method is simple in operation, accurate in measurement, and fast in 3D image reconstruction.

SELECTION OF CITATIONS
SEARCH DETAIL