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1.
Environ Sci Pollut Res Int ; 26(24): 25178-25189, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31256407

ABSTRACT

Today's climate change is a major problem and challenge for the global environment and human civilization, and it can lead to dramatical floods over specific regions. As climate change intensifies, climate change adaptation strategies, such as flood insurance, energy taxes, and other risky financial strategies, have drawn worldwide attention and discussion. Risk control methods have been widely used to mitigate the impact of climate change on past flood losses, but past risk control strategies on climate change have not focused on the exploration of the relationship between environment, society, and humans. Based on the theoretical model of pro-environmental behavior, this study compares and analyzes four theoretical models and proposes a modified competitiveness model to effectively predict the pro-environmental behavior of college students with partial least squares (PLS) manner. Social norm could play a dominant role of mediator between risk perception, place attachment, and pro-environmental behavior. Although risk perception and local attachment are positively related to risk financial strategy, the promotion of social norms will increase the intention of risk financial strategy. For intention of risk financial strategies within pro-environmental behavior, the efficiency of enhancing local attachment was higher than that of risk perception.


Subject(s)
Climate Change , Conservation of Natural Resources , Social Norms , Acclimatization , Adaptation, Physiological , Floods , Humans , Intention , Models, Theoretical , Young Adult
2.
Environ Sci Pollut Res Int ; 26(33): 33936-33945, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30008166

ABSTRACT

Spatial correlation of pollution of the water resource in Taipei, Taiwan, were examined by analyzing the antibiotic resistance patterns (ARPs) of 96 Escherichia coli colonies, which were isolated from 7 sampling sites in 3 river sections. The ARPs were the growth patterns of isolated E. coli colonies in the medium with seven kinds of antibiotics, including ampicillin, chlortetracycline, erythromycin, oxytetracycline, streptomycin, tetracycline, and salinomycin of different concentrations. The results showed that the survival rate of E. coli decreased with increasing concentration of antibiotics; however, various ARPs under different antibiotics of different concentrations significantly increased both the useful information and complexities. Hierarchical cluster analysis (HCA) and two-stage principal component analysis (PCA) were applied to analyze the spatial correlations and interrelations of distinct ARPs among sampling sites in this study. It was found that the seven sampling sites can be categorized into three groups which may represent three possible pollution characteristics.


Subject(s)
Drug Resistance, Microbial/genetics , Environmental Monitoring , Escherichia coli/genetics , Ampicillin , Chlortetracycline , Drug Resistance, Microbial/drug effects , Erythromycin , Escherichia coli/drug effects , Rivers , Streptomycin , Taiwan , Tetracycline , Water Pollution/analysis
3.
Anal Chem ; 90(22): 13796-13805, 2018 11 20.
Article in English | MEDLINE | ID: mdl-30372032

ABSTRACT

Capturing phosphopeptides from complicated biological samples is essential for the discovery of new post-translational modification sites and disease diagnostics. Although several two-dimensional (2-D) materials have been used for phosphopeptides capturing, metal-organic framework (MOF) nanosheets have not been reported. The Ti-based MOF nanosheets have well-defined 2-D morphology, high density of active sites, large surface area, and an ultrathin structure. Phosphopeptides can be efficiently extracted and superior detection limits of 0.1 fmol µL-1 can be achieved even for an extremely low molar ratio of phosphoprotein/nonphosphoprotein (1:10000) mixtures. The selectivity over nonphosphopeptides can be enhanced further by pretreatment with a 10 mM salt solution (ß-glycerophosphate disodium, NaCl, or KCl). The performance of 2-D Ti-based MOF nanosheets is much better than Zr-based MOF (Zr-BTB) nanosheets or any other Ti-based 3-D MOF counterpart, such as MIL-125 and NH2-MIL-125. The nanosheets were used for in situ isotope labeling for abnormally regulated phosphopeptides analysis from serum samples of type 2 diabetes patients. The relative quantitative results showed that three of the phosphorylated fibrinogen peptides A (FPA, DpSGEGDFLAEGGGV, DpSGEGDFLAEGGGVR, and ADpSGEGDFLAEGGGVR) were down-regulated, while the other isoform (ADpSGEGDFLAEGGGV) was up-regulated in the serum samples of type 2 diabetes patients compared with those of healthy volunteers. Finally, proteomics analysis showed selective enrichment of phosphopeptides with 2-D Ti-based MOF nanosheets from real samples, including tryptic digests of mouse brain neocortex lysate, mouse spinal cord lysate, and mouse testis lysate, followed by LC-MS/MS analysis. Total numbers of 2601, 3208, and 2866 phosphopeptides were successfully identified from the three samples, respectively. The 2-D Ti-based MOF nanosheets significantly improved sample preparation for mass spectrometric analysis in phosphopeptides and phosphoproteomics research.


Subject(s)
Diabetes Mellitus/blood , Metal-Organic Frameworks/metabolism , Nanostructures , Peptides/metabolism , Phosphoproteins/blood , Amino Acid Sequence , Animals , Case-Control Studies , Humans , Mice , Peptides/chemistry , Phosphorylation
4.
Anal Chim Acta ; 1032: 91-98, 2018 Nov 22.
Article in English | MEDLINE | ID: mdl-30143226

ABSTRACT

We proposed some exfoliated Ti-based metal-organic frameworks (MOFs) nanosheets as matrices with ultrahigh ionization efficiency, free matrix background, significant dispersibility and acidic resistance. Combining the features between MOFs and 2-D nanomaterials, the NTU-9 nanosheets matrix also demonstrated suitable band gap energy and superior photoabsorption properties, much better than other representative MOFs. A wide range of small molecules that involving low mass region were also analyzed with NTU-9 nanosheets as the matrices in both positive-ion and negative-ion reflector modes. The ultra-efficient NTU-9 nanosheets matrix was successfully applied to serum for quantitative determination of glucose as a clinical diagnosis indicator of diabetes mellitus.


Subject(s)
Carbohydrates/chemistry , Glucose/analysis , Lasers , Metal-Organic Frameworks/chemistry , Nanostructures/chemistry , Titanium/chemistry , Humans , Particle Size
5.
J Am Chem Soc ; 139(24): 8312-8319, 2017 06 21.
Article in English | MEDLINE | ID: mdl-28538098

ABSTRACT

Two-dimensional metal-organic framework (MOF) nanosheets are utilized as effective enzyme inhibitors, providing an inspiring means to enhance the control of cellular processes as well as improve our understanding of the surface chemistry between MOFs and enzymes. In this paper, we demonstrated that the activity of α-chymotrypsin (ChT) can be effectively inhibited with 96.9% inhibition by 2-D Cu(bpy)2(OTf)2 nanosheets, while Zn2(bim)4 nanosheets show no significant inhibition effect toward ChT. Kinetic studies revealed that the material acts as a competitive inhibitor toward ChT. Furthermore, fluorescence and circular dichroism spectroscopy reveal that the 2-D MOF nanosheets do not change the secondary structure of the enzyme. The Cu(II) center of the 2-D nanosheets binds the 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) molecules in the buffer, leading to an electrostatic interaction between the nanosheets and the enzyme. In addition, the irreversible coordination interactions between Cu(II) center and His-57 played an important role during the inhibition process, as supported by ionic strength experiments and UV absorbance changes of Cu(II) d-d transitions. As a result, the substrate is prevented from reaching the active sites of the enzyme causing enzyme inhibition. The modulation of enzyme activity by 2-D MOF nanosheets opens up a new direction for the exploration of the MOF-bio interface in physiological and catalytic systems.


Subject(s)
Chymotrypsin/antagonists & inhibitors , Chymotrypsin/metabolism , Metal-Organic Frameworks/pharmacology , Nanostructures/chemistry , Serine Proteinase Inhibitors/pharmacology , Kinetics , Metal-Organic Frameworks/chemistry , Models, Molecular , Molecular Structure , Osmolar Concentration , Particle Size , Serine Proteinase Inhibitors/chemistry
6.
Chem Commun (Camb) ; 52(88): 12984-12987, 2016 Oct 27.
Article in English | MEDLINE | ID: mdl-27747340

ABSTRACT

Stable 2-D metal-organic framework nanosheets were utilized as a superior clean-background matrix for MALDI-TOF MS analysis of small biomolecules and pollutants in both positive and negative ion modes. The matrix could unusually afford up to 1000 mM of the salt concentrations in the monitoring of the enzymatic hydrolysis of neurotransmitter acetylcholine.

7.
Environ Sci Pollut Res Int ; 23(6): 5255-67, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26561328

ABSTRACT

Decabromodiphenyl ether (DBDE), which has been identified as an endocrine disrupting compound, is used as brominated flame retardant, and this can result in serious bioaccumulation within ecological systems. The objective of this study was to explore DBDE bioremediation (25 mg/kg) using laboratory scale soil slurry microcosms. It was found that effective biodegradation of DBDE occurred in all microcosms. Various biometabolites were identified, namely polybrominated diphenyl ethers congeners and hydroxylated brominated diphenyl ether. Reductive debrominated products such as tri-BDE to hepta-BDE congeners were also detected, and their total concentrations ranged from 77.83 to 91.07 ng/g. The mechanism of DBDE biodegradation in soil slurry microcosms is proposed to consist of a series of biological reactions involving hydroxylation and debromination. Catechol 2,3-oxygenase genes, which are able to bring about meta-cleavage at specific unbrominated locations in carbon backbones, were identified as present during the DBDE biodegradation. No obvious effect on the ecological functional potential based on community-level physiological profiling was observed during DBDE biodegradation, and one major facultative Pseudomonas sp. (99 % similarity) was identified in the various soil slurry microcosms. These findings provide an important basis that should help environmental engineers to design future DBDE bioremediation systems that use a practical microcosm system. A bacterial-mixed culture can be selected as part of the bioaugmentation process for in situ DBDE bioremediation. A soil/water microcosm system can be successfully applied to carry out ex situ DBDE bioremediation.


Subject(s)
Biodegradation, Environmental , Environmental Pollutants , Environmental Restoration and Remediation/methods , Flame Retardants , Halogenated Diphenyl Ethers , Soil Microbiology , Environmental Pollutants/analysis , Environmental Pollutants/isolation & purification , Environmental Pollutants/metabolism , Flame Retardants/analysis , Flame Retardants/isolation & purification , Flame Retardants/metabolism , Halogenated Diphenyl Ethers/analysis , Halogenated Diphenyl Ethers/isolation & purification , Halogenated Diphenyl Ethers/metabolism
8.
Biomed Res Int ; 2014: 765652, 2014.
Article in English | MEDLINE | ID: mdl-25197659

ABSTRACT

Synthetic sewage containing high concentrations of pharmaceuticals and personal care products (PPCPs, mg/L level) was treated using an anoxic/aerobic (A/O) reactor coupled with a microbial fuel cell (MFC) at hydraulic retention time (HRT) of 8 h. A novel design of solid plain graphite plates (SPGRPs) was used for the high surface area biodegradation of the PPCP-containing sewage and for the generation of electricity. The average CODCr and total nitrogen removal efficiencies achieved were 97.20% and 83.75%, respectively. High removal efficiencies of pharmaceuticals, including acetaminophen, ibuprofen, and sulfamethoxazole, were also obtained and ranged from 98.21% to 99.89%. A maximum power density of 532.61 mW/cm(2) and a maximum coulombic efficiency of 25.20% were measured for the SPGRP MFC at the anode. Distinct differences in the bacterial community were presented at various locations including the mixed liquor suspended solids and biofilms. The bacterial groups involved in PPCP biodegradation were identified as Dechloromonas spp., Sphingomonas sp., and Pseudomonas aeruginosa. This design, which couples an A/O reactor with a novel design of SPGRP MFC, allows the simultaneous removal of PPCPs and successful electricity production.


Subject(s)
Bioelectric Energy Sources , Bioreactors , Graphite/chemistry , Household Products/analysis , Pharmaceutical Preparations/isolation & purification , Sewage , Aerobiosis , Anaerobiosis , Bacteria/growth & development , Biodegradation, Environmental , Biodiversity , Bioelectric Energy Sources/microbiology , Bioreactors/microbiology , Denaturing Gradient Gel Electrophoresis , Electricity , Sewage/microbiology , Species Specificity
9.
Bioresour Technol ; 102(18): 8437-44, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21429742

ABSTRACT

Anaerobic fermentative biohydrogen production, the conversion of organic substances especially from organic wastes to hydrogen gas, has become a viable and promising means of producing sustainable energy. Successful biological hydrogen production depends on the overall performance (results of interactions) of bacterial communities, i.e., mixed cultures in reactors. Mixed cultures might provide useful combinations of metabolic pathways for the processing of complex waste material ingredients, thereby supporting the more efficient decomposition and hydrogenation of biomass than pure bacteria species would. Therefore, understanding the relationships between variations in microbial composition and hydrogen production efficiency is the first step in constructing more efficient hydrogen-producing consortia, especially when complex and non-sterilized organic wastes are used as feeding substrates. In this review, we describe recent discoveries on bacterial community composition obtained from dark fermentation biohydrogen production systems, with emphasis on the possible roles of microorganisms that co-exist with common hydrogen producers.


Subject(s)
Biofuels/microbiology , Biotechnology/methods , Clostridium/metabolism , Enterobacter/metabolism , Fermentation/physiology , Hydrogen/metabolism , Anaerobiosis
10.
Dalton Trans ; 39(33): 7659-65, 2010 Sep 07.
Article in English | MEDLINE | ID: mdl-20644894

ABSTRACT

Solvothermal reactions of CuCN with a set of flexible bipyrazolyl-based ligands with different spacer lengths [(dmpz)(CH(2))(n)(dmpz)] (dmpz = 3,5-dimethyl-pyrazolyl; n = 1-6) gave rise to six [CuCN](n)-based coordination polymers [(CuCN)(3)L](n) (1: L = dmpzm; 2: L = dmpze), [(CuCN)(2)L](n) (3: L = dmpzpr; 4: L = dmpzb; 5: L = dmpzp; 6: L = dmpzh). Compounds 1-6were characterized by elemental analysis, IR, powder X-ray diffraction and single-crystal X-ray diffraction. 1 or 2 exhibits a 1D scolopendra-like chain assembled from a rare 1D zigzag [CuCN](n) chain with [CN-Cu-CN-Cu-L] (1: L = dmpzm; 2: L = dmpze) side arms. 3 or 4 shows a 2D (6,3) wave-like layer in which [Cu(6)(mu-CN)(6)L(2)](n) (L = dmpzpr or dmpzb) double chains are interconnected by pairs of L bridges. 5 consists of two [CuCN](n) single chains that are linked by dmpzp bridges to form a rare 1D chain with an oblong channel. has a 3D network in which the 2D [Cu(10)(mu-CN)(10)(dmpzh)(3)](n) layers are interconnected by pairs of dmpzh bridges. In addition, the photoluminescent properties of 1-6 in the solid state at ambient temperature were investigated.

11.
J Ind Microbiol Biotechnol ; 35(11): 1481-91, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18712535

ABSTRACT

Sulfate-reducing bacteria (SRB), which cause microbiologically influenced material corrosion under anoxic conditions, form one of the major groups of microorganisms responsible for the generation of hydrogen sulfide. In this study, which is aimed at reducing the presence of SRB, a novel alternative approach involving the addition of magnesium peroxide (MgO2) compounds involving the use of reagent-grade MgO2 and a commercial product (ORC) was evaluated as a means of inhibiting SRB in laboratory batch columns. Different concentrations of MgO2 were added in the columns when black sulfide sediment had appeared in the columns. The experimental results showed that MgO2 is able to inhibit biogenic sulfide. The number of SRB, the sulfide concentration and the sulfate reducing rate (SRR) were decreased. ORCtrade mark as an additive was able to decrease more effectively the concentration of sulfide in water and the SRB-control effect was maintained over a longer time period when ORCtrade mark was used. The level of oxidation-reduction potential (ORP), which has a linear relationship to the sulfide/sulfate ratio, is a good indicator of SRB activity. As determined by fluorescence in-situ hybridization (FISH), most SRB growth was inhibited under increasing amounts of added MgO2. The concentration of sulfide reflected the abundance of the SRB. Utilization of organic matter greater than the theoretical SRB utilization rate indicated that facultative heterotrophs became dominant after MgO2 was added. The results of this study could supply the useful information for further study on evaluating the solution to biocorrosion problems in practical situations.


Subject(s)
Magnesium Compounds/pharmacology , Oxygen/metabolism , Peroxides/pharmacology , Sulfur-Reducing Bacteria/drug effects , Sulfur-Reducing Bacteria/growth & development , Microbial Viability/drug effects , Sulfates/metabolism , Sulfides/metabolism , Sulfur-Reducing Bacteria/metabolism
12.
Bioresour Technol ; 98(2): 478-83, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16439114

ABSTRACT

This work evaluates the addition of solid phase oxygen, a magnesium peroxide (MgO(2)) formulation manufactured by Regenesis (oxygen-releasing compounds, ORC), to inhibit the production of hydrogen sulfide (H(2)S) in an SRB-enriched environment. The initial rate of release of oxygen by the ORC was determined over a short period by adding sodium sulfite (Na(2)SO(3)), which was a novel approach developed for this study. The ability of ORCs to control H(2)S by releasing oxygen was evaluated in a bench-scale column containing cultured sulfate reducing bacteria (SRB). After a series of batch tests, 0.4% ORC was found to be able to inhibit the formation of H(2)S for more than 40 days. In comparison, the concentration of H(2)S dropped from 20 mg S/L to 0.05 mg S/L immediately after 0.1% hydrogen peroxide (H(2)O(2)) was added, but began to recover just four days later. Thus, H(2)O(2) does not seem to be able to inhibit the production of sulfide for an extended period of time. By providing long-term inhibition of the SRB population, ORC provides a good alternative means of controlling the production of H(2)S in water.


Subject(s)
Hydrogen Sulfide/chemistry , Magnesium Compounds/chemistry , Oxygen/chemistry , Peroxides/chemistry , Water Purification/methods , Water/chemistry , Hydrogen Peroxide/chemistry
13.
Bioresour Technol ; 88(2): 107-13, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12576003

ABSTRACT

Wastewater microorganisms of nitrification and denitrification were cultivated to compose two biofilm modules, termed the permeable support bioreactor (PSB) and the membrane feeding substrate bioreactor (MFSB). PSB and MFSB were combined in a single tank to develop a double-biofilm reactor, which was used to treat nitrogen contaminants in wastewater. With a membrane supplement of substrates (O(2) and CH(3)OH), the D.O. and COD levels were at a low value in the bulk solution thus inhibitive effects between nitrification and denitrification were minimized. Simultaneous nitrification/denitrification was conducted in the reactor and the double-biofilm reactor achieved high nitrification and denitrification efficiency, of 96.5% and 82%, respectively.


Subject(s)
Biofilms , Bioreactors , Nitrogen/isolation & purification , Waste Disposal, Fluid/methods , Water Purification/methods , Membranes, Artificial , Nitrogen/metabolism , Polyvinyl Alcohol/chemistry , Water Movements
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