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Kumar BN, Ramana DKV, Harinath Y, Seshaiah K, Wang MC. Separation and preconcentration of Cd(II), Cu(II), Ni(II), and Pb(II) in water and food samples using Amberlite XAD-2 functionalized with 3-(2-nitrophenyl)-1H-1,2,4-triazole-5(4H)-thione and determination by inductively coupled plasma-atomic emission spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:11352-11358. [PMID: 21919486 DOI: 10.1021/jf202409c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A separation and preconcentration procedure was developed for the determination of trace amounts of Cd(II), Cu(II), Ni(II), and Pb(II) in water and food samples using Amberlite XAD-2 fuctionalized with a new chelating ligand, 3-(2-nitrophenyl)-1H-1,2,4-triazole-5(4H)-thione (Amberlite XAD-2-NPTT). The chelating resin was characterized by Fourier transform infrared spectroscopy (FT-IR) and used as a solid sorbent for enrichment of analytes from samples. The sorbed elements were subsequently eluted with 10 mL of 1.0 M HNO(3), and the eluates were analyzed by inductively coupled plasma-atomic emission spectrometry. The influences of the analytical parameters including pH, amount of adsorbent, eluent type and volume, flow rate of the sample solution, volume of the sample solution, and effect of matrix on the preconcentration of metal ions have been studied. The optimum pH for the sorption of four metal ions was about 6.0. The limits of detection were found to be 0.22, 0.18, 0.20, and 0.16 μg L(-1) for Cd(II), Cu(II), Ni(II), and Pb(II), respectively, with a preconcentration factor 60. The proposed method was applied successfully for the determination of metal ions in water and food samples.
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Chang Chien SW, Chang CH, Chen SH, Wang MC, Madhava Rao M, Satya Veni S. Effect of sunlight irradiation on photocatalytic pyrene degradation in contaminated soils by micro-nano size TiO2. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:4101-4108. [PMID: 21762957 DOI: 10.1016/j.scitotenv.2011.06.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 06/12/2011] [Accepted: 06/22/2011] [Indexed: 05/31/2023]
Abstract
The enhanced catalytic pyrene degradation in quartz sand and alluvial and red soils by micro-nano size TiO(2) in the presence and absence of sunlight was investigated. The results showed that the synergistic effect of sunlight irradiation and TiO(2) was more efficient on pyrene degradation in quartz sand and red and alluvial soils than the corresponding reaction system without sunlight irradiation. In the presence of sunlight irradiation, the photooxidation (without TiO(2)) of pyrene was very pronounced in alluvial and red soils and especially in quartz sand. However, in the absence of sunlight irradiation, the catalytic pyrene degradation by TiO(2) and the photooxidation (without TiO(2)) of pyrene were almost nil. This implicates that ultra-violet (UV) wavelength range of sunlight plays an important role in TiO(2)-enhanced photocatalytic pyrene degradation and in photooxidation (without TiO(2)) of pyrene. The percentages of photocatalytic pyrene degradation by TiO(2) in quartz sand, alluvial and red soils under sunlight irradiation were 78.3, 23.4, and 31.8%, respectively, at 5h reaction period with a 5% (w/w) dose of the amended catalyst. The sequence of TiO(2)-enhanced catalytic pyrene degradation in quartz sand and alluvial and red soils was quartz sand>red soil>alluvial soil, due to different texture and total organic carbon (TOC) contents of the quartz sand and other two soils. The differential Fourier transform infrared (FT-IR) spectra of degraded pyrene in alluvial soil corroborate that TiO(2)-enhanced photocatalytic degradation rate of degraded pyrene was much greater than photooxidation (without TiO(2)) rate of degraded pyrene. Based on the data obtained, the importance for the application of TiO(2)-enhanced photocatalytic pyrene degradation and associated organic contaminants in contaminated soils was elucidated.
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Chang Chien SW, Chang CH, Chen SH, Wang MC, Madhava Rao M, Satya Veni S. Oxidative degradation of pyrene in contaminated soils by δ-MnO2 with or without sunlight irradiation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:4078-86. [PMID: 21752426 DOI: 10.1016/j.scitotenv.2011.06.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 06/01/2011] [Accepted: 06/07/2011] [Indexed: 05/21/2023]
Abstract
The enhanced oxidative degradation of pyrene in quartz sand and alluvial and red soils by micro-nano size birnessite (δ-MnO(2)) in the presence and absence of sunlight was investigated. The degradation of pyrene by δ-MnO(2) in quartz sand showed very little synergistic effect of sunlight irradiation on δ-MnO(2) oxidizing power. However, pyrene degradation by δ-MnO(2) in alluvial and red soils was greater under solar irradiation than the combination of photooxidation of pyrene and oxidation of pyrene by δ-MnO(2). The oxidative degradation percentages of pyrene by δ-MnO(2) under sunlight irradiation are 94.8, 97.7, and 100% for alluvial soil, red soil, and quartz sand, respectively. Oxidative degradation percentages of pyrene by δ-MnO(2) in alluvial and red soils with irradiation of sunlight almost attained a maximum at 1 h with a 5% (w/w) dose of the amended oxidant. Due to their different total organic carbon (TOC) contents, the sequence of enhanced oxidative degradation of pyrene by δ-MnO(2) in quartz sand and alluvial and red soils was quartz sand>red soil>alluvial soil. Further, this study revealed that δ-MnO(2)-enhanced oxidative degradation of pyrene is very pronounced in contaminated soils in situ even at deep soil layers where irradiation by sunlight is very limited.
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Resnick LB, Wang MC, Kaplan J. Task analysis in curriculum design: a hierarchically sequenced introductory mathematics curriculum. J Appl Behav Anal 2010; 6:679-709. [PMID: 16795452 PMCID: PMC1310886 DOI: 10.1901/jaba.1973.6-679] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A method of systematic task analysis is applied to the problem of designing a sequence of learning objectives that will provide an optimal match for the child's natural sequence of acquisition of mathematical skills and concepts. The authors begin by proposing an operational definition of the number concept in the form of a set of behaviors which, taken together, permit the inference that the child has an abstract concept of "number". These are the "objectives" of the curriculum. Each behavior in the defining set is then subjected to an analysis that identifies hypothesized components of skilled performance and prerequisites for learning these components. On the basis of these analyses, specific sequences of learning objectives are proposed. The proposed sequences are hypothesized to be those that will best facilitate learning, by maximizing transfer from earlier to later objectives. Relevant literature on early learning and cognitive development is considered in conjunction with the analyses and the resulting sequences. The paper concludes with a discussion of the ways in which the curriculum can be implemented and studied in schools. Examples of data on individual children are presented, and the use of such data for improving the curriculum itself, as well as for examining the effects of other treatment variables, is considered.
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Chang Chien SW, Chen CY, Chang JH, Chen SH, Wang MC, Mannepalli MR. Sorption of toluene by humic acids derived from lake sediment and mountain soil at different pH. JOURNAL OF HAZARDOUS MATERIALS 2010; 177:1068-1076. [PMID: 20106594 DOI: 10.1016/j.jhazmat.2010.01.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 12/17/2009] [Accepted: 01/06/2010] [Indexed: 05/28/2023]
Abstract
Contamination of soil and groundwater with BTEX compounds (benzene, toluene, ethylbenzene, and xylene) depends on the sorption behavior of these compounds by soil organic matter (SOM) and humic acids (HAs). In this study sorption of toluene by HAs extracted from lake sediment and mountain soil was investigated. HA suspensions were adjusted to pH 4.00, 6.00, or 8.00 and made to the concentration of 200 mg L(-1). Each HA suspension or solution was subjected to particle size analysis using high performance particle sizer (HPPS). The particle size of HA from lake sediment was around 1000-1200 nm while that from mountain soil was 220-320 nm at suspension pH 4.00. Kinetic studies showed that sorption of toluene by the two HAs followed pseudo-first-order and mainly pseudo-zero-order kinetics. At suspension pH 4.00, the sorption of toluene by the two HAs was best described by Langmuir and Temkin adsorption isotherm models. Further, sorption of toluene by the lake sediment HA was significantly greater than that by mountain soil HA. It was thus suggested that the lake sediment HA with larger particle size may develop beneficially chemical conformation for sorption of toluene and related compounds in soil and associated environments.
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Reddy DHK, Seshaiah K, Reddy AVR, Rao MM, Wang MC. Biosorption of Pb2+ from aqueous solutions by Moringa oleifera bark: equilibrium and kinetic studies. JOURNAL OF HAZARDOUS MATERIALS 2010; 174:831-8. [PMID: 19853374 DOI: 10.1016/j.jhazmat.2009.09.128] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 09/25/2009] [Accepted: 09/25/2009] [Indexed: 05/19/2023]
Abstract
Biosorption of Pb(2+) from aqueous solution by biomass prepared from Moringa oleifera bark (MOB), an agricultural solid waste has been studied. Parameters that influence the biosorption such as pH, biosorbent dose, contact time and concentration of metal ion were investigated. The experimental equilibrium adsorption data were tested by four widely used two-parameter equations, the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherms. Results indicated that the data of Pb(2+) adsorption onto MOB were best fit by the Freundlich model. The adsorption capacity (Q(m)) calculated from the Langmuir isotherm was 34.6mgPb(2+)g(-1) at an initial pH of 5.0. Adsorption kinetics data were analyzed using the pseudo-first-, pseudo-second-order equations and intraparticle diffusion models. The results indicated that the adsorption kinetic data were best described by pseudo-second-order model. Infrared (IR) spectral analysis revealed that the lead ions were chelated to hydroxyl and/or carboxyl functional groups present on the surface of MOB. Biosorbent was effective in removing lead in the presence of common metal ions like Na(+), K(+), Ca(2+) and Mg(2+) present in water. Desorption studies were carried out with dilute hydrochloric acid for quantitative recovery of the metal ion as well as to regenerate the adsorbent. Based on the results obtained such as good uptake capacity, rapid kinetics, and its low cost, M. oleifera bark appears to be a promising biosorbent material for the removal of heavy metal ions from wastewater/effluents.
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Rao MM, Ramana DK, Seshaiah K, Wang MC, Chien SWC. Removal of some metal ions by activated carbon prepared from Phaseolus aureus hulls. JOURNAL OF HAZARDOUS MATERIALS 2009; 166:1006-1013. [PMID: 19135782 DOI: 10.1016/j.jhazmat.2008.12.002] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2008] [Revised: 11/15/2008] [Accepted: 12/01/2008] [Indexed: 05/27/2023]
Abstract
Removal of lead [Pb(II)], zinc [Zn(II)], copper [Cu(II)], and cadmium [Cd(II)] from aqueous solutions using activated carbon prepared from Phaseolus aureus hulls (ACPAH), an agricultural waste was studied. The influence of various parameters such as effect of pH, contact time, adsorbent dose, and initial concentration of metal ions on the removal was evaluated by batch method. The removal of metal ions by ACPAH was pH dependent and the optimum pH values were 7.0, 8.0, 7.0 and 6.0 for Cu(II), Cd(II), Zn(II), and Pb(II), respectively. The sorption isotherms were studied using Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin isotherm models. The maximum adsorption capacity values of ACPAH for metal ions were 21.8 mg g(-1) for Pb(II), 21.2 mg g(-1) for Zn(II), 19.5 mg g(-1) for Cu(II), and 15.7 mg g(-1) for Cd(II). The experiments demonstrated that the removal of metal ions followed the pseudo-second-order kinetic model. Desorption experiments were carried out using HCl solution with a view to regenerate the spent adsorbent and to recover the adsorbed metal ions.
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Chang Chien SW, Chen HL, Wang MC, Seshaiah K. Oxidative degradation and associated mineralization of catechol, hydroquinone and resorcinol catalyzed by birnessite. CHEMOSPHERE 2009; 74:1125-1133. [PMID: 19028396 DOI: 10.1016/j.chemosphere.2008.10.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 10/10/2008] [Accepted: 10/14/2008] [Indexed: 05/27/2023]
Abstract
Abiotic degradation and mineralization of catechol, hydroquinone, and resorcinol catalyzed by birnessite (delta-MnO2) was investigated. Studies were carried out by monitoring changes of pE versus time and pH versus time of the reaction systems during the initial 10 h reaction period and release of CO2 and associated reactions at the end of a 90 h reaction period. The reactions under anoxic condition were compared with aeration condition. The reactions were carried out in suspensions at initial pH of 6.0 under air and N2 atmosphere at room temperature and free of microbial activity. These results indicated that kinetic-related changes of pE versus time and pH versus time were dependent on structural characteristics of phenolic compound and aeration or anoxic condition in the reaction system. The sequence of the mineralization of phenolic compounds catalyzed by delta-MnO2 in presence of air expressed by CO2 release was catechol > hydroquinone > or = resorcinol and the differences were significant. However, under an N2 atmosphere the amounts of CO2 released were drastically reduced with insignificant differences among the three reaction systems. Further, phenolic compound degradations, dissolved and adsorbed Mn, and oxidation state of Mn in delta-MnO2 were also determined to elucidate the catalytic efficacy mediated by both O2 and delta-MnO2 in the reaction systems.
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MacLeod KE, Gee GC, Crawford P, Wang MC. Neighbourhood environment as a predictor of television watching among girls. J Epidemiol Community Health 2008; 62:288-92. [PMID: 18339819 DOI: 10.1136/jech.2007.061424] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Television watching, a sedentary activity, has been associated with overweight in children. While the family environment is known to influence television watching, little is known about the influence of the neighbourhood environment. This study is an exploratory examination of the association of socioeconomic characteristics of the neighbourhood environment with television watching among 9-10 year old girls. METHODS Data collected by the Berkeley site of the National Heart, Lung and Blood Institute Growth and Health Study (NGHS) in 1987-8 from 787 girls who had a complete set of measurements relevant to the analysis were used. These measures included parental education, household income, race and weekly hours spent watching television. Addresses of the girls were geocoded and the median household income for the census tracts in which they lived was used to indicate neighbourhood socioeconomic characteristics. Multilevel modelling procedures were used to estimate fixed effect coefficients for individual and neighbourhood level variables. RESULTS Living in high income areas was associated with less television watching, a finding that held even when controlling for parental education, household income and race. Race and parental education were also associated with television watching. CONCLUSION Television watching among girls was associated not only with the socioeconomic characteristics of their households, but also of their neighbourhoods. Future studies should explore the mechanisms that mediate this relation and determine if these results are generalisable to other populations.
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Lin HT, Wang MC, Seshaiah K. Mobility of adsorbed arsenic in two calcareous soils as influenced by water extract of compost. CHEMOSPHERE 2008; 71:742-749. [PMID: 18035393 DOI: 10.1016/j.chemosphere.2007.10.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2007] [Revised: 10/08/2007] [Accepted: 10/11/2007] [Indexed: 05/25/2023]
Abstract
The mobility of arsenic (As) in soil affects both the bio-toxicity of As and the groundwater quality, which in turn indirectly affects the quality of edible part of crops and human health, if the crops were irrigated with As contaminated groundwater. A vertical soil column simulates the depth of a soil profile in a real soil environment. Thus soil column experiment is much more pertinent to soil environment than a batch experiment to simulate solute movement as well as leaching through soil profile. A laboratory soil column experiment was conducted to determine the extent of As leaching from soil percolated with influent that contained organic substances. The water extract of compost (WEC) was used as the source of organic substances. The results of As breakthrough curves (BTCs) showed that less pore volumes of influents were required to reach the relative concentration ratio of 1 (C/C0=1) for the two calcareous soils treated with influent that contained WEC. The concentrations of As in the column effluents of soils percolated with 0.01M KCl in WEC were significantly higher than those percolated with 0.01M KCl with the same volumes of effluents collected. This clearly indicates that dissolved as well as deprotonated organic substances which are negatively charged have higher potential for competing the adsorption sites with As on soils, leading to increasing mobility of As in soil and associated environments. Further, it is observed that the characteristics of soil components related to As adsorption affected the adsorption as well as desorption processes and subsequent mobility of As in soil environment as influenced by organic substances.
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Rao MM, Rao GPC, Seshaiah K, Choudary NV, Wang MC. Activated carbon from Ceiba pentandra hulls, an agricultural waste, as an adsorbent in the removal of lead and zinc from aqueous solutions. WASTE MANAGEMENT (NEW YORK, N.Y.) 2008; 28:849-58. [PMID: 17416512 DOI: 10.1016/j.wasman.2007.01.017] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Revised: 11/07/2006] [Accepted: 01/19/2007] [Indexed: 05/14/2023]
Abstract
The ability of low-cost activated carbon prepared from Ceiba pentandra hulls, an agricultural waste material, for the removal of lead and zinc from aqueous solutions has been investigated. In the batch tests experimental parameters were studied, including solution pH, contact time, adsorbent dose and initial metal ions concentration. The adsorbent exhibited good sorption potential at pH 6.0. Maximum removal of lead (99.5%) and of zinc (99.1%) with 10 g/l of sorbent was observed at 50 mg/L sorbate concentration. Removals of about 60-70% occurred in 10 min, and equilibrium was attained at around 50 min for both metals. The functional groups (CO, SO,-OH) present on the carbon surface were responsible for the adsorption of metal ions. The adsorption parameters were analysed using both the Freundlich and Langmuir models. The data are better fitted by the Freundlich isotherm as compared to Langmuir model, and the adsorption capacities for lead and zinc were 25.5 and 24.1 mg/g, respectively. Kinetics of adsorption obeyed a second order rate equation and the rate constant was found to be 2.71 x 10(-2) and 2.08 x 10(-2) g/mg/min for lead and zinc, respectively. The desorption studies were carried out using dilute HCl, and the effect of HCl concentration on desorption was studied. Maximum desorptions of 85% for lead and 78% for zinc were attained with 0.15 M HCl.
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Chien SWC, Wang MC, Huang CC, Seshaiah K. Characterization of humic substances derived from swine manure-based compost and correlation of their characteristics with reactivities with heavy metals. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:4820-7. [PMID: 17497878 DOI: 10.1021/jf070021d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Various composts contain a significant amount of humic substances including humic acid (HA) and fulvic acids (FAs). The FA fraction in soils is considered to be sensitive to agronomic and environmental factors. In this study, three fractions of humic substances, HA (MW > 1000 Da), FA (MW > 1000 Da), and FA (MW < 1000 Da) were extracted from swine manure-based compost and characterized, and then, their reactivities were correlated with heavy metals. Compositions of the three fractions of humic substances were characterized by elemental and total acidity analyses and electron spin resonance (ESR), Fourier transform infrared (FTIR), and 13C nuclear magnetic resonance with cross-polarization and magic-angle spinning spectroscopic techniques. Elemental analyses indicated that HA has higher contents of C, H, N, and S than those of FAs. However, FA (MW > 1000) and especially FA (MW < 1000) have higher contents of O than that of HA (MW > 1000). The g values of the ESR spectra of the three fractions showed that the organic free radical characteristics and the widths of the spectra and free radical concentrations of the three fractions are significantly different. The FTIR spectra indicated that HA (MW > 1000) is abundant in C=C bonds while FA (MW > 1000), especially FA (MW < 1000), are abundant in C=O bonds. In addition, 13C NMR spectra indicate that carboxyl contents of FA (MW > 1000), especially FA (MW < 1000), are higher than that of HA (MW > 1000). The sequence of the reactivity in terms of acidic functional groups was FA (MW < 1000) > FA (MW > 1000) > HA (MW > 1000). Elemental and functional group compositions of the three fractions significantly correlated with reported reactivities with heavy metals. The application of swine manure-based compost containing HA and FAs fractions to soil and associated environments may thus significantly affect the concerned reactions with organic and inorganic compounds including pollutants.
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Tseng CC, Huang JJ, Wang MC, Wu AB, Ko WC, Chen WC, Wu JJ. PapG II adhesin in the establishment and persistence of Escherichia coli infection in mouse kidneys. Kidney Int 2007; 71:764-70. [PMID: 17290293 DOI: 10.1038/sj.ki.5002111] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Most human pyelonephritogenic Escherichia coli express the PapG II adhesin. However, the role of the PapG II adhesin in enhancing the establishment and persistence of E. coli infection in the kidney is controversial. A pyelonephritogenic strain, EC114, which possesses one copy of the papG II gene, but without other virulence factors (such as S/F1C-fimbriae, hemolysin, and cytotoxic necrotizing factor 1) was selected for the construction of a papG II mutant. The resulting papG II mutant was confirmed by polymerase chain reaction, Southern hybridization, and agglutination assay, and designated as MEC114. We compared MEC114 with the parental strain (EC114) for colonization ability in the bladder and kidney of female BALB/c mice, which were challenged transurethrally with 50 microl of a low (5x10(4) CFU (colony-forming unit)) or high (5x10(8) CFU) dose of EC114 or MEC114 and assessed 1, 3, and 7 days after inoculation. Geometric means of quantitative bacterial counts in the kidney were significantly decreased when challenged with MEC114 on day 3 after inoculation, at both low and high dose (P<0.05), as compared with EC114. On the seventh day, both strains were mainly cleared from the kidney. Renal biopsy showed a similar degree of inflammatory response to both strains 1, 3, and 7 days after inoculation. In brief, the PapG II adhesin can enhance the early establishment of E. coli infection in the kidney, but the bacteria do not maintain infection owing to the host immune response.
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Chien SWC, Wang MC, Chiu CL, Lin YM, Lai SY. The contents and forms of solid-phase species of radioactive strontium and cesium in Taiwan soils. ENVIRONMENTAL MONITORING AND ASSESSMENT 2007; 125:29-39. [PMID: 16927194 DOI: 10.1007/s10661-006-9236-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Accepted: 03/01/2006] [Indexed: 05/11/2023]
Abstract
This study was to investigate the activities and contents of (137)Cs in the profiles of selected arable and forest soils in Taiwan and various solid-phase species of (85)Sr and (137)Cs in selected arable soils in Taiwan. The gamma (gamma) ray spectra of the collected soil samples and some of the soils amended with (85)Sr and (137)Cs were measured. The data indicate that the arable soils from Sanhsing series, Sanhsing Township and Chuangwei series, Chuangwei Township, Ilan County, and from Tunglochuan series, Pinglin Township, Taipei County shows significantly higher radioactivity of (137)Cs (ND - 11.0 +/- 0.2 Bq kg(-1)). Furthermore, the radioactivity of (137)Cs in the mountain soils (1.24 +/- 0.07 - 42 +/- 1 Bq kg(-1)) from Yuanyang Lake Nature Preserve among Ilan, Taoyuan, and Hsinchu Counties is the highest among the investigated mountain forest soils. This may be mainly attributed to the fact that Ilan County is located in the northeastern part of Taiwan and faces the northeastern and northern seasonal winds with lots of precipitation annually from mid-autumn through mid-spring next year and is receiving greater amount of fallouts yearly. Due to longer reaction period (>or=3 y) of (137)Cs with soil components, (137)Cs was mainly in the forms bound to oxides and to organic matter in the soil amended with (137)Cs and in the soil contaminated with (137)Cs. On the contrary, due to shorter reaction period (<60 d) of (85)Sr with soil components, (85)Sr was mainly in exchangeable form and partially in the forms bound to carbonates and oxides in the soils amended with (85)Sr.
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Liao YC, Chien SWC, Wang MC, Shen Y, Hung PL, Das B. Effect of transpiration on Pb uptake by lettuce and on water soluble low molecular weight organic acids in rhizosphere. CHEMOSPHERE 2006; 65:343-51. [PMID: 16554084 DOI: 10.1016/j.chemosphere.2006.02.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 02/04/2006] [Accepted: 02/06/2006] [Indexed: 05/07/2023]
Abstract
The effect of transpiration (high and low) on Pb uptake by leaf lettuce and on water soluble low molecular weight organic acids (LMWOAs) in rhizosphere has been studied. After two weeks of growth the plants were cultured in greenhouse for more four weeks and two days. Pb(NO(3))(2) solutions of different concentrations (100, 200, and 300 mg l(-1) of Pb) were then added to the quartz sand pots of different plants and studies were initiated. Blank experiments (without treating the quartz sand pots with Pb(NO(3))(2) solutions) were also run in parallel. No significant differences in the growth of the plants with the concentrations of added Pb(NO(3))(2) solutions were observed by both low and high transpirations at the end of the 0, 3rd, and 10th days of studies. The total evaporation of the volatiles during 10 days did not depend on the concentration of Pb(2+) but with high transpiration the rate of evaporation was significantly higher than with low transpiration. Uptake of Pb by shoots and roots of the plants was found to be proportional to the concentration of various Pb(NO(3))(2) solutions added and more accumulation was observed in roots than in shoots at the end of 3rd and 10th days. High transpiration created more Pb uptake than low transpiration did. One volatile acid, propionic acid and nine non-volatile acids, lactic, glycolic, oxalic, succinic, fumaric, oxalacetic, D-tartaric, trans-aconitic, and citric acids in rhizosphere quartz sands were identified and quantified by gas chromatography (GC) analysis. D-Tartaric and citric acids were major among the non-volatile acids. The amount of LMWOAs in rhizosphere quartz sands increased with the higher amount of Pb uptake and also with the duration of studies. The total quantities of the LMWOAs in the rhizosphere quartz sands were significantly higher under high transpiration with 300 mg l(-1) Pb solution addition at the end of 10th day. The present study shows prominent correlation between transpiration and uptake of heavy metal and interesting correlation between Pb contaminated level and quantity of water soluble LMWOAs in rhizosphere quartz sands. The latter thus deserves of further studies.
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Chang Chien SW, Wang MC, Hsu JH, Seshaiah K. Influence of fertilizers applied to a paddy-upland rotation on characteristics of soil organic carbon and humic acids. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:6790-9. [PMID: 16939341 DOI: 10.1021/jf061275m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The qualitative and quantitative characteristics of soil organic carbon (SOC) and related humic acids (HAs) extracted from the soils of field plots were investigated after 8 years of annual paddy (Oryza sativa L.) and upland maize (Zea mays L.) rotation with various fertilizations. Seven fertilization treatments were selected: Ck (no inputs); Chem (chemical fertilizer of NPK); Comp (swine compost); Comp + 33% of Chem N rate; Comp + 67% of Chem N rate; GM (legume green manure) + 33% of Chem N rate; and peat + 33% of Chem N rate. Organic and inorganic nitrogen inputs of six treatments were equivalent with respect of nitrogen content, but Comp, GM, and peat treatments were complemented with various amounts of inorganic N. After harvest of the eighth paddy crop, surface soil samples collected from the plots were subjected to soil characterizations and extraction of humic substances, which were used for chemical, spectroscopic (FTIR, 13C NMR, ESR, X-ray diffractometry), delta13C, and 14C dating analyses. The yields of HAs extracted from the seven treatments were significantly different. Treatment containing persistent organic compound such as the peat + 33% N treatment increased the humification process in topsoils and produced higher yield of HA. Spectroscopic analyses revealed that fertilization treatments changed the functional groups, alkyl C, crystalline characteristics, and delta13C ratios of HAs and turnover rate of SOC considerably. The SOC of the peat + 33% N treatment had the highest mean residence time of 3100 years. Various fertilizer treatments are correlated with turnover rate of SOC and related HAs, which are associated with concerned carbon sequestration as well as mitigation of CO2 emission in the soil environment.
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Chang Chien SW, Wang MC, Huang CC. Reactions of compost-derived humic substances with lead, copper, cadmium, and zinc. CHEMOSPHERE 2006; 64:1353-61. [PMID: 16490235 DOI: 10.1016/j.chemosphere.2005.12.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2005] [Revised: 12/07/2005] [Accepted: 12/19/2005] [Indexed: 05/06/2023]
Abstract
Thermodynamic stability constants of the formation of complexes from the reactions of humic substances with various metals are usually used as parameters to judge the reactivities of both humic substances and metals. However, in calculating the thermodynamic stability constants, complicated processes for the acquisition of activities of components in reactions are absolutely inevitable. In this study, we investigated the average conditional concentration quotients of the complexes formed from the reaction of metals with humic substances and the relations of these quotients to thermodynamic stability constants. The characterized humic substances including HA (MW>1,000), FA (MW>1,000), and FA (MW<1,000) extracted from a swine compost were prepared to react with Pb, Cu, Cd, and Zn at 25 degrees C and at pH 4.00 and 6.50. Reactions of HA (MW>1,000), FA (MW>1,000), and FA (MW<1,000) with the four metals were carried out at 1:0.1, 1:0.5, 1:1, 1:5, and 1:10 ligand:metal stoichiometry. The concentrations of the free ions of Pb, Cu, Cd, and Zn in the reaction systems of metal-HA suspensions and metal-FA solutions were measured by anodic stripping voltammetry (ASV). The sequence of the average conditional concentration quotients of the formed complexes from the reaction of humic substances with metals was FA(MW<1,000)>FA(MW>1,000)>HA(MW>1,000), showing the relative reactivities of the fractions of swine compost-derived humic substances. The sequence of reacting metals with humic substances was Pb>Cu>Cd>Zn, which is in good agreement with the sequence reported by judging the thermodynamic stability constants. The average conditional concentration quotients of the formed complexes from the reaction of humic substances with metals were thus useful parameters that can be directly related to thermodynamic stability constants and other parameters.
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Wang MC, Liu SX, Liu PB. Gene expression profile of multiple myeloma cell line treated by realgar. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2006; 25:243-9. [PMID: 16918137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In order to elucidate the molecular mechanism of Realgar treatment for multiple myeloma (MM), cDNA microaaray was used to compare the gene expression profiles of MM cell line RPMI8226 at 72 hrs pre- and post-Realgar treatment on three separate days. 54 up-regulated and 60 down-regulated genes were identified by cDNA microarray. Further analysis screened out 17 up-regulated and 3 down-regulated genes with Z-score greater than 2 or less than -2, which can be considered the significantly altered genes after Realgar treatment in this study. CCL2, CCL3, BTG1,TNFAIP3, TNFAIP8, SLC38A2, IGFBP4 were important up-regulated genes and they were associated with a variety of cell life functions such as cell growth, cell-cell signaling, regulation of apoptosis and cell homeostasis based on biological process of gene. There are only 3 significantly down-regulated genes (Z-score <-2.0) involved in muscle contract. Several of these genes have been previously identified in relation to MM in published papers. Subsequent validation of selected genes (CCL2, TNFAIP3 and BTG1) by reverse transcription polymerase chain reaction was consistent with our microarray analysis. CCL2 may be involved in MM pathobiology by tumor growth suppression. BTG1 could be used as a potential treatment-related biomarker for monitoring the therapy effect and the remission status of leukemia patients.
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Rao GPC, Seshaiah K, Rao YK, Wang MC. Solid phase extraction of Cd, Cu, and Ni from leafy vegetables and plant leaves using amberlite XAD-2 functionalized with 2-hydroxy-acetophenone-thiosemicarbazone (HAPTSC) and determination by inductively coupled plasma atomic emission spectroscopy. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:2868-72. [PMID: 16608202 DOI: 10.1021/jf0600049] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A method for solid phase extraction of trace metals, namely, Cd, Cu, and Ni, using Amberlite XAD-2 functionalized with a new chelating ligand, 2-hydroxy-acetophenone-3-thiosemicarbazone (Amberlite XAD-2-HAPTSC), has been developed. The optimum experimental conditions for the quantitative sorption of three metals, pH, effect of flow rate, concentration of eluent, sorption capacity, kinetics of sorption, and the effect of diverse ions on the sorption of analytes have been investigated. The chelating resin could be reused for more than 20 cycles of sorption-desorption without any significant change (<1.5%). The accuracy of the proposed procedure was evaluated by standard reference materials. The proposed method was applied for the determination of trace metal ions in leafy vegetable samples collected from different sources and medicinal plant leaves.
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Wang MC, Bachrach LK, Van Loan M, Hudes M, Flegal KM, Crawford PB. The relative contributions of lean tissue mass and fat mass to bone density in young women. Bone 2005; 37:474-81. [PMID: 16040285 DOI: 10.1016/j.bone.2005.04.038] [Citation(s) in RCA: 187] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Revised: 03/25/2005] [Accepted: 04/29/2005] [Indexed: 11/29/2022]
Abstract
Although obesity is associated with increased risk of many chronic diseases including cardiovascular disease, diabetes, hypertension, and cancer, there is little evidence to suggest that obesity increases risk of osteoporosis. In fact, both weight and body mass index (BMI) are positive predictors of bone mass in adults, suggesting that those who are overweight or obese may be at lower risk of osteoporosis. However, recent evidence suggests that in children and adolescents, obesity may be associated with lower rather than higher bone mass. To understand the relation of fat mass to bone mass, we examined data gathered from an ethnically diverse group of 921 young women, aged 20-25 years (317 African Americans, 154 Asians, 322 Caucasians, and 128 Latinas) to determine how fat mass (FM) as well as lean tissue mass (LTM) is associated with bone mass. Bone mass, FM, and LTM were measured using dual energy X-ray absorptiometry (GE Lunar Corp, Madison, WI). Bone mass was expressed as bone mineral density (BMD; g/cm2) and bone mineral apparent density (BMAD; g/cm3) for the spine and femoral neck, and as BMD and bone mineral content (BMC; g) for the whole body. Regression techniques were used to examine the following: (1) in separate equations, the associations of LTM and FM with each bone mass parameter; and (2) in the same equation, the independent contributions of LTM and FM to bone mass. LTM and FM were positively correlated with BMD at all skeletal sites. When the contributions of FM and LTM were examined simultaneously, both FM and LTM continued to be positively associated with bone mass parameters but the effect of FM was noted to be smaller than that of LTM. We conclude that in young women, LTM has a greater effect than fat mass on bone density per kg of tissue mass.
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Lin HT, Wang MC, Li GC. Complexation of arsenate with humic substance in water extract of compost. CHEMOSPHERE 2004; 56:1105-1112. [PMID: 15276723 DOI: 10.1016/j.chemosphere.2004.05.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2003] [Revised: 04/29/2004] [Accepted: 05/10/2004] [Indexed: 05/24/2023]
Abstract
The interactions of environmental toxicants with organic substances affect the speciation and dynamics, and subsequent toxicity, mobility, and fate of toxicants in the environment. For the purpose of understanding the complexation of As(V) with humic substances, arsenate-containing solutions with As concentrations from 1 to 8 mgl(-1) were prepared to react with the water extract of compost (WEC). All the reaction systems including the control were incubated for 48 h at 25 degrees C. The complexation of As(V) with humic substance was examined by dialysis and ion exchange techniques. From 30% to 51% of added As(V) reacted with organic substance in WEC to form an As-metal-organic complex. This was verified as a hydrophobic organic fraction after separation of As-metal-organic complex fraction from the hydrophilic fraction by XAD-8 resin. The complex substance was also identified as a humic substance by the method of proton binding formation function determination. This suggests that cations, such as Ca and Mg, and especially Fe, Al, and Mn act in cation bridging in the complexation of As(V) with humic substance. The role of metals in the complexation of As(V) with humic substance in terrestrial and especially aquatic environments thus merits close attention.
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Yang KY, Wang MC, Yeo SJ, Lo NN. Minimally invasive unicondylar versus total condylar knee arthroplasty--early results of a matched-pair comparison. Singapore Med J 2003; 44:559-62. [PMID: 15007494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Fifty consecutive patients with isolated medial compartmental osteoarthritis of the knee were treated with minimally invasive unicompartmental knee arthroplasty (UKA). An equal number of patients with total knee arthroplasty (TKA) performed in the same period were selected and matched with respect to age, pre-operative range of motion and radiological grade of knee arthrosis. Both groups of patients were prospectively followed up. Comparison of the two groups at six months show that patients with minimally invasive UKA have less blood loss, quicker rehabilitation, earlier ambulation, shorter hospitalisation stay and better post-operative range-of-motion with reduced hospitalisation cost. Reflecting on a six-month follow-up and immediate post-operative events, we conclude that minimally invasive UKA is a relatively more cost effective procedure than TKA for these patients.
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Abstract
The soil-flushing method enhanced by ultrasonic waves is a new technique that potentially can become an effective method for in situ remediation of the ground contaminated by NAPL hydrocarbons. This study investigated the effectiveness of ultrasound enhancement in the soil-flushing method for a range of conditions involving soil type, soil density, flushing rate, and sonication power. The study was conducted in the laboratory using specially designed and fabricated equipment. The test results indicated that the rate of contaminant extraction increased considerably with increasing sonication power up to the level where cavitation occurred. The effectiveness of sonication-enhanced soil-flushing can be expressed as a function of (D(10))(2)*i, in which D(10) is the effective grain size, and i is the hydraulic gradient.
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Wang MC, Chen HM. Forms and distribution of selenium at different depths and among particle size fractions of three Taiwan soils. CHEMOSPHERE 2003; 52:585-593. [PMID: 12738296 DOI: 10.1016/s0045-6535(03)00240-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The bioavailability of selenium in soils for plants depends more on its forms than on its total concentration. The purpose of the present study was to examine the solid-phase forms of selenium at different depths of three soil series representing major farming soil groups in Taiwan as well as the amounts of selenium in sand, silt and clay fractions of the soils. The study was conducted by means of sequential extraction to obtain the amounts of selenium and the distribution of various solid-phase forms of selenium at different depths of Pinchen (121 degrees 11(')E, 24 degrees 55(')N), Toulun-Sheto (120 degrees 55(')E, 24 degrees 50(')N), and Chunliao (120 degrees 25(')E, 23 degrees 57(')N) soil series. The amounts of metal oxide-bound form of selenium in the three soil series were the largest, with those of Pinchen and Toulun-Sheto soil series exceeding 50% of the total amounts of selenium and that of Chunliao soil series maintained at 30-40%. In the Pinchen and Toulun-Sheto soil series, the amounts of selenium in clay fractions were the largest, with a significant difference between the clays with and without metal oxides and organic matter removed. The amounts of selenium remained high in silt and/or sand fractions of the Chunliao soil series with metal oxides and organic matter removed. Metal oxide and organic matter contents of the three soil series mainly affect the amounts of various solid-phase forms of selenium and their distribution in different depths and particle size fractions of the soils. This observation of selenium associated with soil constituents was in good agreement with the results of the adsorption of selenite and selenate by the three soil series.
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Zhang SX, Tani T, Yamaji S, Ma CM, Wang MC, Cai- SQ, Zhao YY. Glycosyl flavonoids from the roots and rhizomes of Asarum longerhizomatosum. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2003; 5:25-30. [PMID: 12608635 DOI: 10.1080/1028602031000080423] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Two new glycosyl flavonoids including a glycosyl aurone, together with six known flavonoids were isolated from the roots and rhizomes of Asarum longerhizomatosum. The structures of the two new compounds were elucidated as 4,6,4'-trihydroxy-aurone-4,6-di-O-beta-D-glucopyranoside (7, caulesauroneside) and naringenin-7,4'-di-O-beta-D-glucopyranoside (8, caulesnarinside). The six known flavonoids were identified as naringenin (1), naringenin-5-O-beta-D-glucopyranoside (2), naringenin-7-O-beta-D-glucopyranoside (3), chalcononaringenin-2'-O-beta-D-glucopyranoside (4), naringenin-5,7-di-O-beta-D-glucopyranoside (5), chalcononaringenin-2',4'-di-O-beta-D-glucopyranoside (6), respectively. This is the first report of the isolation of aurones in the family Aristolochiaceae.
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