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ABSTRACTProjects aimed at recording the unique values and characteristics of geographical regions, in terms of human, social, and economic aspects, have been increasing in number, along with plans to apply these data to future planning directions. However, such projects tend to develop gradually and in a uniform direction, contrary to its original intention. To address these problems, a survey method with consideration for regional characteristics is presented here. In addition, after local lifestyle is investigated, more effective procedures are needed to ensure that outcomes are actively utilized in local revitalization plans and that residents can access and use the data. This study proposes improvement directions for the South Korean context via examination of the progress, characteristics, and limitations of utilization of the results of such life-culture projects, based on a multiple case analysis of these projects in Seoul.

Agricultural environment is often contaminated with various chemicals (e.g., pesticides, heavy metals) and microplastics due to the uses of plastic products. The effects of chemical contaminants or microplastics on terrestrial environment have been extensively studied, but the studies on the co-presence of chemical contaminants and microplastics are relatively limited. This study was set to investigate the effect of co-presence of microplastics (i.e., low-density polyethylene (LDPE) and polyvinyl chloride (PVC) microplastic films) and chemical contaminants (i.e., cadmium (Cd) and procymidone (PCM)) in soil on the lettuce growth and Cd and PCM uptake by lettuce using pot tests. The lettuce leaf lengths were not affected by the presence of only Cd or PCM, but the rates of change in the lettuce leaf number were adversely affected by the presence of PCM. The presence of only LDPE or PVC in soil at the concentrations used in this study did not have significant impacts on the lettuce growth. But the co-presence of Cd and LDPE and the co-presence of PCM and PVC resulted in the negligible increases in the lettuce leaf length and leaf number with time, although the lettuce growths were statistically similar in the Cd- or PCM-contaminated soils regardless of the presence of microplastics. The results suggest that the adverse effects of Cd or PCM can be intensified by the co-presence of microplastics, and the effects can be different depending on the types of microplastics. The promoted adverse effects of chemical contaminants in the co-presence of microplastics can be supported by the tendency of the increased absorption of Cd or PCM by lettuce in the co-presence of microplastics. Overall, this study shows the need for management of both chemical contaminants and microplastics that may reside in the agricultural environment.

ABSTRACTThe purpose of this study is to propose a direction for improvement by analyzing the characteristics of Goshiwon, non-dwellings. For this purpose, before analyzing the policy alternatives and plans for improvement, this study classify the highly density area of Goshiwons by analyzing the characteristics of its residents. First, this study derived the process and limitations of the related laws by analyzing the policies and regulations about the domestic Goshiwons. Second, this study analyzed the precedent research and case studies about domestic Goshiwons. Third, the types of Goshiwons were classified according to the distribution of resident types. Finally, this study proposes a policy alternative by analyzing the planning characteristics of the representative cases by types.

For the efficient separation of lipid extracted from microalgae cells, a novel membrane was devised by introducing a functional polymer coating onto a membrane surface by means of an initiated chemical vapor deposition (iCVD) process. To this end, a steel-use-stainless (SUS) membrane was modified in a way that its surface energy was systemically modified. The surface modification by conformal coating of functional polymer film allowed for selective separation of oil–water mixture, by harnessing the tuned interfacial energy between each liquid phase and the membrane surface. The surface-modified membrane, when used with chloroform-based solvent, exhibited superb permeate flux, breakthrough pressure, and also separation yield: it allowed separation of 95.5 ± 1.2% of converted lipid (FAME) in the chloroform phase from the water/MeOH phase with microalgal debris. This result clearly supported that the membrane-based lipid separation is indeed facilitated by way of membrane being functionalized, enabling us to simplify the whole downstream process of microalgae-derived biodiesel production.

AbstractMalachite green (MG) has been widely used in the dyeing industry and as a fungicide and an antiseptic in the aquaculture industry. However, MG is very dangerous and cytotoxic to mammalian cells, and its discharge into receiving waters results in environmental problems in aquatic ecosystems. To remove this soluble dye from aqueous solutions, adsorption by inorganic clay is often used. In the case of the triphenylmethane dye family, molecular structure changes occur with changes in pH. As a result, chromatic MG+at a neutral pH turns into the protonated MG (MGH2+) at an acidic pH and into the carbinol base form at a basic pH. In this study, taking into consideration the potential for MG structural change, batch sorption experiments for kinetics (5–1.17, 10–2.94, and 20–5.90 MG mg/mL at 293, 303, and 313 K) and thermodynamics (calculated activation energy (Ea) = 2.09 kJ/mol) as well as tests of the feasibility of column flushing were conducted using talc to remove MG from aqueous solutions (100% removal after 140 pore volumes of a 12-h run). We studied specific removal behaviors of MG by talc for pH values > 8.0, where MG molecules that had adsorbed onto the talc predominantly changed to the carbinol base form and were retained on the talc.

We investigated the effect of particle size during oxidation and the sono-Fenton process in an open-air system (without air supply) containing microscale zero-valent iron (MZVI) and nanoscale zero-valent iron (nZVI) on the degradation of 1,4-dioxane (1,4-D) at neutral pH. Time-dependent concentrations of 1,4-D, H2O2, and ionic Fe were measured as a function of MZVI and nZVI loading during oxidation and sono-Fenton (without addition of H2O2). The optimal loading of MZVI and nZVI for 1,4-D degradation were determined to be 0.5 g/L during both oxidation and sono-Fenton, and 0.2 and 0.1 g/L during both oxidation and sono-Fenton, respectively. Overall, the optimal loading of MZVI in both the oxidation and sono-Fenton system showed better 1,4-D degradation efficiency compared with the optimal loading of nZVI for 6 h: approximately 60.00 and 76.65% removal efficiencies for MZVI oxidation and sono-Fenton, respectively, while approximately 47.13 and 60.98% removal efficiencies for nZVI oxidation and sono-Fenton, respectively. Consequently, the smaller size of ZVI did not enhance 1,4-D degradation efficiency during the oxidation and sono-Fenton at neutral pH.

Abstract: Water extract of ginseng was fermented using various lactic acid bacteria, and their anti-Helicobacter pylori activity was evaluated. The fermented ginseng extracts evidenced anti-H. pylori activity, including anti-bacterial, anti-adhesion, and urease inhibition effects. Among the four types of lactic acid bacteria, Lactobacillus plantarum MG 208 evidenced the most profound anti-H. pylori activity in fermented ginseng. Therefore, fermented ginseng extract containing L.plantarum MG 208 could prove useful as functional diet for the protection of the gastric environment against H. pylori.

Enveloping porphyrin arrays: Supramolecular arrays of self‐assembled tetrakis(4‐sulfonatophenyl)porphyrin (TPPS) molecules have been enveloped with an ultrathin layer of titanium dioxide (see picture; scale bar: 25 nm). Integration of the hybrid components at close‐to‐molecular dimensions preserves optical and chiral properties of J‐aggregate superstructures but also enhances photocatalytic activity of TiO2.

The authors present a light extraction improvement at a low operation voltage from p-GaN patterned InGaN/GaN light-emitting diodes (LEDs) fabricated using size-controllable nanosphere lithography and subsequent inductively coupled plasma etching. A 300-nm polystyrene (PS) nanosphere array was used as an etching mask in order to produce ordered pillar patterns on the p-GaN layer, during which the top and bottom size of the pillars were tailored to optimize the electrical and optical properties by varying the diameter of the PS nanosphere masks. Three LEDs, without patterns and with pillar patterns of 210 nm and 240 nm diameter, were compared with each other, in which the LED with 240 nm diameter pillar patterns showed the highest output power (32.6% higher than that of the LEDs without patterns) in both its electroluminescence and photoluminescence measurements.

Trichloroethylene (TCE) is a common contaminant in water and groundwater, known as suspected carcinogens, and its presence in the environment is of significant concern. Nano-scale zero-valent iron (NZVI) has emerged as an excellent reduction catalyst due to fast degradation of chlorinated solvents. However aggregation of NZVI is a serious limitation. In this study, NZVI was coated with nonionic surfactant to overcome its aggregation and to enhance its dispersion. The synthesized NZVI using water-based solution method produced nanowire-like structures mostly and a few portion of NZVI showed a spherical shape. For the modification of NZVI by surfactant, the amount of Tween 80® used to be adsorbed onto NZVI was ca. 8 mmol/kg of NZVI. The volume size distribution of the obtained surfactant modified NZVI (SNZVI) increased to d90%(cumulative size at 90%) = 2.03 µm and at 0.79 µm of mean size, while that of bare NZVI had diameter with d90%(cumulative size at 90%) = 14.12 µm and at 4.54 µm of mean size. The maximum adsorption amount of humic acid (HA) onto SNZVI was 18.70 mg/g and that of NZVI was 20.05 mg/g. For TCE removal in the presence of HA, SNZVI was not enhanced for TCE removal efficiency, compared with NZVI removal. And TCE removal using SNZVI was inhibited as HA concentration increased, but TCE degradation efficiency increased at high concentration of HA. Based on reduction of size and the reactivity of SNZVI, the present results can be applied for in situ groundwater remediation.

Iron(III)‐entrapped γ‐alumina nanosorbents were prepared by an environmentally benign method using an ionothermal process based on an ionic liquid to synthesize the γ‐alumina host and a sonochemical method to entrap the iron(III) guest. The morphology of the alumina depends on the aluminum precursor used, giving aligned bundled and randomly debundled γ‐alumina nanorods as well as wormlike mesoporous alumina. In particular, the rodlike structure shows significantly greater mesoporosity than the wormlike porous γ‐alumina structure. Moreover, entrapment of iron(III) in the γ‐alumina nanosorbents with randomly debundled rodlike structures leads to the greatest AsVremoval capacity and the fastest adsorption rate as compared to the other FeIII‐entrapped adsorbents, as a result of its larger surface area and pore sizes. Thus, this method provides a clean and effective route to an advanced host–guest adsorbent system for application in the removal of arsenic from drinking water.

Methyl mercaptan oxidase was successfully induced inThiobacillus thioparusTK-m using methyl mercaptan gas, and was purified for the detection of mercaptans. The purification procedure involved a DEAE (diethylaminoethyl)-Sephacel, or Superose 12, column chromatography, with recovery yields of 47.5 and 48.5%, and specific activities of 374 and 1240.8 units/mg-protein, respectively. The molecular weight of the purified methyl mercaptan oxidase was 66.1kDa, as determined by SDS-PAGE. The extract, from gel filtration chromatography, oxidizes methyl mercaptan, producing formaldehyde, which can be easily detected by the purpald-coloring method. The optimized temperature for activity was found to be at 55°C. This enzyme was inhibited by both NH4Cl and (NH4)2SO4, but was unaffected by either KCl or NaCl at less than 200 mM. With K2SO4, the activity decreased at 20 mM, but recovered at 150 mM. In the presence of methanol, full activity was maintained, but decreased in the presence of glycerin, ethanol and acetone 43, 78 and 75%, respectively.

Removal of hydrophobic organic contaminants (HOCs) using an additive-enhanced electrokinetic method was studied in a model system. Kaolinite and phenanthrene were selected as a model clay soil and a representative HOC, respectively. Three different chemically-synthesized surfactants along with two different biosurfactants were used to remove phenanthrene. Hydrogen peroxide was also used to degrade phenanthrene. Electrokinetic (EK) column experiments were performed using these additives. When no additive was used, a removal efficiency of phenanthrene was 4.23% after 2 weeks. When surfactants were added in the EK system, the removal efficiencies after 2 weeks were as follows: APG 11.1%, Brij 30 6.31%, SDS 9.97%, MEL 16.2% and BS-UC 17.4%. Among surfactants, biosurfactants had higher removal efficiencies than chemically-synthesized surfactants. When hydrogen peroxide was used, 54.7% of initial amount was removed at a current of 5 mA for 2 weeks. Even a higher removal efficiency was achieved (84.2%) at 10 mA within 1 week. These results suggest a detailed future study on the chemical treatment by hydrogen peroxide incorporated with EK method to remove phenanthrene from clay soil.

Summary: A series of pH/temperature-sensitive hydrogels composed of maleilated chitosan (MC) and N-isopropylacrylamide (NIPAAm) were prepared and characterized with respect to their swelling behaviors, change of lower critical solution temperature (LCST). These hydrogels showed broad pH-sensitivities below 32 °C, but above that temperature exhibited sharp pH-dependent phase transition behaviors which depended on the content of MC in the hydrogels. The change of ratio of NIPAAm to MC in weight did not affect LCST significantly, while it affected equilibrium water content (EWC) at high pH region. The hydrogels also exhibited a typical of reversibility depending on temperature and pH.

Summary: Biodegradable alginate-derived polymeric surfactants (APSs) with a linear alkyl group (C8, C12, C16) were synthesized by oxidation followed by reductive amination of 2,3-dialdehydic alginate. The oxidized alginates and all APSs were characterized by spectral and X-ray diffractometry analysis. The sonicated suspension test was employed to form self-aggregates in aqueous solution. In the case of 40% CHO-C8 APS, the lowest interfacial tension, 31.5 mNm−1, was obtained at the c.m.c. value of 1.35 g L−1. A biodegradability test on the 30% CHO-C12 APS system suggested that it would be attacked by a soil microorganism, Aspergillus niger.

Methyl mercaptan oxidase was successfully induced fromRhodococcus rhodochrousIGTS8 using methyl mercaptan gas and purified to homogeneity for the detection of mecrcaptans. The purification procedure involved DEAE-Sephacel and Superose 12 column chromatography with recovery yields of 85.8 and 83.3%, and a specific activity of 92.7 and 303.4 units/mg-protein, respectively. The molecular weight of purified methyl mercaptan, oxidase was determined to be 64.5 kDa by SDS-PAGE. The extract from gel filtration chromatography oxidizes methyl mercaptan to produce formaldehyde, which can be easily detected by the purpald-coloring method. Optimum temperature for activity was achieved at 60°C. This enzyme was inhibited by both K2SO4and NaCl at concentration of less than 100 mM and recovered to original activity at concentration of 200 mM. In the presence of methanol, the activity decreased by 33%.

ABSTRACTPulsed-field gel electrophoresis, ribotyping, and fingerprinting analysis of 22 invasive isolates of multidrug-resistant (MDR) pneumococci from Korea showed that 59 to 82% were genetically related. DNA sequencing of the PBP 2B gene showed relatively uniform alterations in nucleotides (5.4 to 7.8%) and amino acids (3.0 to 4.3%), while Asn-276?Lys, Arg-285?Cys and Ser-305?Phe substitutions were unique to Korean MDR strains, suggesting the spread of a few epidemic clones of resistant pneumococci within Korea.

Glycolipids produced byPseudomonas aeruginosaYPJ-80 were characterized by chromatographic and spectroscopic techniques as a mixture of two rhamnolipids. For recovery of glycolipids from the culture broth, various isolation methods including ultrafiltration, adsorption and solvent extraction were compared. Ultrafiltration showed the best results in terms of glycolipids recovery. Further purification for spectroscopic analysis was carried out by adsorption chromatography and preparation thin layer chromatography. From the spectroscopic analysis, such as IR spectroscopy, FAB-MS,1H-NMR and13C-NMR and hydrolysis analysis, the glycolipids were identified as L-α-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoate and 2-O-α-L-rhamnopyranosyl-α-L-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoate. Monorhamnolipid and dirhamnolipid lowered the surface tension of water to 28.1 mN/m and 29.3 mN/m, respectively.

Normal root of Hyoscyamus nigerwas cultivated in various nutrient conditions to optimize root growth and scopolamine production. Nitrate or phosphate concentration had little effect on root growth, while the low levels of nitrate or phosphate enhanced specific scopolamine content by 44% and 39%, respectively. Glucose or fructose was not adequate for the root culture as a carbon source, while the root growth was markedly enhanced at high sucrose concentration (up to 9%). The growth rate (0.59g dw./L.d.) and scopolamine productivity (1.98 mg/L.d.) was increased greater in roots with 9% initial sucrose concentration as compared to 3% sucrose (0.28 g dw./L.d., 0.98 mg/L.d.)

Production of galacto-oligosaccharide (GO), including trisaccharide and tetrasaccharide, was performed using a β-galactosidase in water-hydrophobic solvent mixtures. A maximum GO concentration of 45% (w/w) was attained in a 95% cyclohexane/5% water mixture from a 55% (w/w) of lactose at 60°C and pH 6.0, while a maximum of 38% GO in aqueous media. GO production decreased with an increase in surfactant concentration. The optimum water content for GO production showed a broad range from 2.5 to 10% (v/v). Solvent properties, such as log P and the dipole moment, had no relation to GO production.

Lipases and proteases from different sources were screened for their ability to catalyze the transesterification of glucose and activated N-blocked phenylalanine. A commercial protease from Bacillus licheniformiswas found to be most effective for this purpose. On a basis of 13C-NMR analysis, glucose was acylated at the C-6 position. The enzyme showed a broad substrate specificity toward various monosaccharides.

Chlorella vulgaris was cultivated in wastewater discharged from a steel-making plant with the aim of developing an economically feasible system to remove ammonia from wastewater and CO2 from flue gas simultaneously. Since no phosphorus compounds existed in wastewater, external phosphate (15·3–46·0 g m^-3) was added to the wastewater. After adaptation to 5% (v/v) CO2, the growth of C. vulgaris was significantly improved at a typical concentration of CO2 in flue gas of 15% (v/v). Growth of C. vulgaris in raw wastewater was better than that in wastewater buffered with HEPES at 15% (v/v) CO2. CO2 fixation and ammonia removal rates were estimated as 26·0 g CO2 m^-3 h^-1 and 0·92 g NH3 m^-3 h^-1, respectively, when the alga was cultivated in wastewater supplemented with 46·0 g PO4³ m^-3 without pH control at 15% (v/v) CO2. © 1997 SCI.

Root tips of Hyoscyamus niger were cultivated on agar or in liquid medium, and patterns of elongation and branching were investigated. The elongation of roots compared to branching, particularly tertiary root branching, was more effective in liquid medium than on agar medium. The number (0.06 per cm) of tertiary roots which branched out from secondary roots was far less than that (4.2 per cm) of secondary roots from primary root particularly in liquid medium. When the secondary roots were cut from the primary root in liquid medium, branching of tertiary roots was markedly enhanced, from 8.4 to 17.5. Scopolamine content in the cut roots increased by 46.3% compared to that in normal roots.

Chlorella vulgarisUTEX259 was cultivated using two different methods of gas supply. In one method the CO2concentration in bubbled gas was held constant and in the other method it was increased gradually. Algal growth was almost linear after a short period of lag phase in both methods. With the constant CO2concentration, the CO2fixation rate in the linear growth phase decreased over 10%(v/v) CO2, while the rate increased up to 6% CO2. However, the rate was enhanced by using the latter incremental increase method, especially under a higher concentration of CO2. The maximum rate of CO2fixation was 52 mg CO2/l·h at 20% CO2during the gradual increase of CO2concentration.

AbstractRemoval of copper from a solution was investigated to evaluate the cation-exchange capacities of apple residues from agricultural wastes. The effects of solution pH, ionic strength, co-ion, ligands, initial metal concentrations, and particle size of apple residues were studied. The optimal pH range for copper removal by apple residues was shown to be from pH 5.5 to 7.0, and the maximum percentage of copper removal was 91.2%. Increasing ionic strength, up to 0.1 N, has little effect on metal uptake. The presence of co-ions such as lead decreases the removal capacity of copper as expected. The presence of ligands, such as EDTA and ammonia, also reduces metal removal efficiency due to the formation of a metal-ligand complexation in solution. Equilibrium of copper sorption was established very rapidly initially and decreased markedly after 1 hour. Equilibrium isotherms of copper fit the Langmuir equation adequately. Column experiments showed that the dynamic capacity of chemically modified apple residues was four to five times higher than that of raw residues which contained acidic groups such as carboxylic and phenolic functional groups. The adsorbed copper ions were completely recovered with three bed volumes of 0.5 N HCl. Thus, modified apple residues could be applied successfully for metal removal from wastewater.

A simple method of UV-spectrophotometric assay for biosolubilized coals was developed. An optimum wavelength for the assay was found to be in the range of 430 to 470 nm. An acid precipitation step must be included in order to remove microbial metabolites and media components before the assay.

A simple purification method has been developed in which flavonoid compounds are selectively adsorbed onto a polycarboxyl ester resin (XAD-7) from methanol extract of ginkgo leaves. When 1.0 g dried gingko leaves was extracted with 100 ml of methanol, about 98% of total flavonoid compounds was recovered by selective adsorption. The pH did not affect the adsorption of flavonoids but at high pH the chemical structure of flavonoids was changed and the adsorption decreased to almost zero. As the solution polarity played a key role in the selective adsorption, the amount of water added to the methanol extract was critical for the recovery and loading of flavonoids. Using standard flavonoids, kaempferol and quercetin, the optimal water content was 80% and the recovery was 80% with 10 g of resin dosage/l. [ABSTRACT FROM AUTHOR]

Emerging evidences have reported that periodontitis can be a risk factor for the pathogenesis of various systemic diseases. Porphyromonas gingivalis(Pg), one of the crucial pathogens in chronic periodontitis, has been spotlighted as a potential cause for the promotion and acceleration of periodontitis-associated systemic disorders. To investigate the association between Pgand intestinal disease or homeostasis, we treated Pg-derived lipopolysaccharide (LPS) in murine colitis model or intestinal organoid, respectively. Pg-derived LPS (PgLPS) was administrated into chemically induced murine colitis model and disease symptoms were monitored compared with the infusion of LPS derived from E. coli(EcLPS). Organoids isolated and cultured from mouse small intestine were treated with Pgor EcLPS and further analyzed for the generation and composition of organoids. In vivo observations demonstrated that both Pgand EcLPS exerted slight protective effects against murine colitis. PgLPS did not affect the generation and growth of intestinal epithelial organoids. Among subtypes of epithelial cells, markers for stem cells, goblet cells or Paneth cells were changed in response to PgLPS. Taken together, these results indicate that PgLPS leads to partial improvement in colitis and that its treatment does not significantly affect the self-organization of intestinal organoids but may regulate the epithelial composition.

The pH-stat fed-batch culture of Pseudomonas aeruginosaYPJ-80 was done to produce a rhamnolipid biosurfactant. With glucose as the sole carbon source, the final concentrations of cells and rhamnolipid biosurfactant obtained in 25 h were 25 g cell dry weight/l and 4.4 g/l, respectively.

We demonstrate improved electrical and optical properties of indium tin oxide (ITO)/Al reflectors, via SF6plasma treatments, for vertical-type GaN light emitting diodes. A 200 nm thick ITO film was deposited and annealed at 650°Cto obtain ohmic contacts with p-GaN, after which SF6and O2plasma were applied on ITO before the Al deposition to effectively increase the work function of ITO and decrease the roughness of the ITO surface. The SF6plasma-treated ITO/Al reflector showed the lowest specific contact resistance of 9.83×10−4Ωcm2and the highest reflectance of 91% at 460 nm, compared to as-deposited and O2plasma-treated ITO/Al reflectors.