• Journal of Environmental Science International
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• v.33 no.8
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• pp.575-581
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• 2024

Insect pests are a significant threat to stored crops and can lead to considerable economic losses and reduced crop quality. Traditional pest control methods often involve chemical treatments, which have adverse environmental and health effects. This study evaluated the effectiveness of controlling the environment using LED lighting and plant-derived odor barriers as a dual strategy for insect pest control. The storage environment was altered using LED lights that emitted specific wavelengths (580-585 nm) and by reducing other wavelengths (300-500 nm). This light environment was combined with an insect odor barrier derived from Cinnamomum verum, Illicium verum, and Artemisia annua, and their duel impact on the behavior and frequency of insect pests under real storage conditions was determined. The findings revealed significant changes in the frequencies of various insect orders, indicating differential responses to light wavelengths and odor barriers. Notably, the introduction of an anti-insect light and odor barrier environment reduced Diptera and Hemiptera frequencies, which could potentially reduce pest intrusion. The results underscore the potential use of integrated light and odor barriers as a noninvasive and environmentally friendly approach to pest management. This study identifies the specific wavelengths and odor combinations that effectively deter insect pests and contribute to the development of more efficient and sustainable pest control methods. It also highlights the importance of understanding insect behavior and frequency changes in response to novel deterrent strategies.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.150-157
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• 2010

In this study, we investigated the differences of mapping understanding and the types of mapping errors by the levels of students' cognitive/affective variables and the relationships between mapping understanding and these variables in learning 'concentration and reaction rate' with analogy. After administering the tests regarding logical thinking ability, visual imagery ability, analogical reasoning ability, self efficacy, and need for cognition as pretests, students learned with analogy. Then, students' familiarity and mapping understanding were examined. Analyses of the results revealed that the scores of the mapping understanding for the students with higher levels of all cognitive/affective variables except visual imagery ability and familiarity were significantly higher than those for the students with lower levels. The differences in the types of the mapping errors such as overmapping, failure to map, impossible mapping, artificial mapping, mismapping, rash mapping, and retention of a base feature were also found by the levels of students' cognitive and affective variables. The scores of students' mapping understanding were positively correlated with those of all cognitive and affective variables. The results of multiple regression analysis indicated that students' science achievement, logical thinking ability, and familiarity were significant predictors of mapping understanding. Educational implications of these findings are discussed.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.446-452
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• 2003

Some new nanohybrid materials have been synthesized by intercalating the oxotitanium(IV) meso-tetrakis(4- sulfonatophenyl) porphyrin$(O=Ti^{(IV)} TSPP)$ into the Zn/Al layered double hydroxides (LDHs), and their structures and photophysical properties have been investigated by various laser spectroscopic techniques. According to the XRD pattern of the synthesized nanohybrid materials, the macrocycle plane of $O=Ti^{(IV)}$ TSPP are grafted perpendicular to the LDH layers. The $O=Ti^{(IV)}$ TSPP-intercalated LDH exhibits band broadening of the absorption spectrum and a blue shift of Q-band as compared to that observed in solution. Resonance Raman spectral measurements demonstrate that the positively charged LDHs give rise to a slight decrease of the electronic density of the porphyrin ring accompanying a small change of the electronic distribution of the $O=Ti^{(IV)}$ TSPP. Consequently the LDH environment affects the energies of the two highest occupied molecular orbitals (HOMOs) of the $O=Ti^{(IV)}$) TSPP, $a_{1u}$ and $a_{2u}$, producing a mixed orbital character. Being consistent with these electronic structural changes of $O=Ti^{(IV)}$ TSPP in LDH, both the fluorescence spectral change and the fsdiffuse reflectance transient measurements imply that the photoexcitation of the $O=Ti^{(IV)}$ TSPP intercalated into LDH undergoes fast relaxation to the O=Ti(IV) $TSPP^+-LDH^- $charge transfer (CT) state within a few picoseconds, followed by a photoinduced electron transfer between the O=Ti(IV) TSPP and LDHs with a rate constant greater than %1×10^{10}S^{-1}$. No evidence is found for back electron transfer. In conclusion, the $O=Ti^{(IV)}$ TSPP intercalated LDH seems to be a possible candidate for an artificial reaction center for an efficient solar energy conversion system.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.509-518
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• 2011

In this study, we investigated the effects of analogy-generating in small group in elementary science-gifted education upon the types and the mapping errors of student-generated analogies, and the perceptions of the instruction. Fifth graders (N=37) at two science-gifted classes in two elementary schools were selected and assigned to individualistic analogygenerating (IA, n=19) and pair analogy-generating (PA, n=18) groups. After the students of each group performed the experiment and were taught about 'saturated solution' concept in the first class, they administered the test on the self-generating analogies on the concept in the second class. The students in the PA group also administered the test on perceptions of analogy-generating in small group and some of them were interviewed deeply. The results revealed that the students in the PA group made more verbal/pictorial, structural/functional, enriched, and higher systematic analogies than those in the IA group. However, there were little difference between the two groups in the subcategories of artificiality (artificial and everyday) and abstraction (abstract and concrete). The students in the PA group fewer mapping errors than those in the IA group. Many students in PA group perceived the analogy-generating in small group positively upon various cognitive and motivational aspects. However, they also pointed a few disadvantages of the activity. Educational implications of these findings are discussed.

• The Journal of Engineering Geology
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• v.13 no.1
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• pp.1-16
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• 2003

Geochemical characteristics of groundwater in the different kinds of various lithology such as Haman formation, Panyaweol formation, Jusan andesitic formation and Palgongsan granite is distinguished by mineralogical and chemical compositions. The Concentration of the majority of solutes in groundwaters of Haman and Panyaweol formation is higher than in that of andesite and granite. Higher concentration of $HCO_3^{-}{\;}and{\;}SO_4^{2-}$ anions in the groundwater is peculiar. High concentrations of $Ca^{2+},{\;}Mg^{2+},{\;}HCO_3^{-}$ in the groundwaters of the sedimentary rocks result mainly from reaction of $CO^{2-}$ charged water with calcite and weathered feldspars. With the Piper diagram, the groundwaters of Haman formations are mainly plotted in $CaSO_4-CaCl_2$ type, whereas those of Panyaweol formations are plotted in the bothside of $Ca(HCO_3)_2{\;}and{\;}CaSO_4-CaCl_2$ type. Thses two different types of $Ca(HCO_3)_2{\;}and{\;}CaSO_4-CaCl_2$ groundwater were originated from dissolution of calcite($Ca(HCO_3)_2)$ and the oxidation of pyrite($CaSO_4-CaCl_2$), respectively. And it also is influenced by anthropogenic contamination. Three factors were extracted from the factor analysis for chemical data. Factor 1, controlled by $SO_4^{2-},{\;}Na^{+},{\;}Ca^{2+}$ and Fe, explains the dissolution of calcite, plagioclase and oxidation of pyrite. Factor 2, controlled by $HCO_3^{-}{\;}and{\;}Mg^{2+}$, mainly explains the dissolution of Mg-carbonates and dolomitization. Factor 3, controlled by $Cl^{-},{\;}K^{+}{\;}and{\;}NO_3^{-}$, is subject to the influence of artificial pollution including industrial waste water disposal. In this study area, some industrial complex which is close to Keumho river show the higher score of factor 3.

• Journal of the Korean Society of Tobacco Science
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• v.13 no.2
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• pp.5-20
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• 1991

For the quality enhancement of harvested-year leaf tobacco to the quality of 2-year naturally aged leaf tobacco, cellulose and nicotine degradative bacteria were isolated and identified. Effects of artificial fermentation treated cellulase and nicotine degradative bacteria on the quality of leaf tobacco were investigated from the chemical and sensory points of view. 1, Changes in chemical composition of leaf tobacco resulted from the addition of cellulase extracted from Cellulomonas sp. [3ml(${\mu}{\textrm}{m}$ D-glucose/ml. mil-1) of enzymes solution 11009 of leaf tobacco] and nicotine degradative bacteria, Pseudomonas sp. 2ml(IX109 cells$\div$ 100g of leaf tobacco), and subsequently fermented at 40${\mu}{\textrm}{m}$$^{\circ}C$, 65% R. H. for 40 days are as follows : 1) Content of crude fiber decreased 12% It took 9 min, 53 sec. to reach full combustion in control group but took only 7 min. 47 sec. in the treated group, taking almost equal time to 2-year naturally aged leaf tobacco(7 min. 35sec.). 2) Light intensity of control group was 60.96% with bright lemon color but that of treated leaf tobacco accounted for 47.69 with orange to dark brown color series, which was almost equal to the value, 45.69, of 2-year naturally aged leaf tobacco. 3) Linoleic acid, serving mild taste among organic acids, amounted to 1.llmg/g in control group but increased to 1.35m9/9 in the treated leaf tobacco, identical to the content(1.35mg/g) of 2-year naturally aged leaf tobacco. 4) Content of solanone, on of the typical leaf tobacco flavor compounds, accounted for 2.95% in control group but increased to 2.87% in treated group. 5) Methyl furan, useful flavor compound in smoke composition, accounted for 17.6$\mu\textrm{g}$/cig. in control group but increased to 25.9$\mu\textrm{g}$/cig. in treated group. However, acroleine decreased from 69.3$\mu\textrm{g}$/cig. in control group to 58.6$\mu\textrm{g}$/cig. in treated group 2. In sonsory test, mild taste evaluation of control group scored 5.47 and treated group 7.93 which was evaluted almost equal to the value(8.00) of 2-year naturally aged leaf tobacco. Aroma evaluation of control group scored 5.60, treated group 8.20, and 2-year naturally aged leaf tobacco 8.33. In addition, total harmony taste of control group showed 5.67, treated group 8.07 (p<0.01), and 2-year naturally aged leaf tobacco 8.00. From these results, it can be said that quality of treated leaf tobacco is not inferior to that 2-year naturally aged leaf tobacco.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1141-1141
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• 2001

The aim of the study was to evaluate the performance of 3 calibration methods, modified partial least squares (MPLS), local PLS (LOCAL) and artificial neural network (ANN) on the prediction of chemical composition of forages, using a large NIR database. The study used forage samples (n=25,977) from Australia, Europe (Belgium, Germany, Italy and Sweden) and North America (Canada and U.S.A) with information relative to moisture, crude protein and neutral detergent fibre content. The spectra of the samples were collected with 10 different Foss NIR Systems instruments, which were either standardized or not standardized to one master instrument. The spectra were trimmed to a wavelength range between 1100 and 2498 nm. Two data sets, one standardized (IVAL) and the other not standardized (SVAL) were used as independent validation sets, but 10% of both sets were omitted and kept for later expansion of the calibration database. The remaining samples were combined into one database (n=21,696), which was split into 75% calibration (CALBASE) and 25% validation (VALBASE). The chemical components in the 3 validation data sets were predicted with each model derived from CALBASE using the calibration database before and after it was expanded with 10% of the samples from IVAL and SVAL data sets. Calibration performance was evaluated using standard error of prediction corrected for bias (SEP(C)), bias, slope and R2. None of the models appeared to be consistently better across all validation sets. VALBASE was predicted well by all models, with smaller SEP(C) and bias values than for IVAL and SVAL. This was not surprising as VALBASE was selected from the calibration database and it had a sample population similar to CALBASE, whereas IVAL and SVAL were completely independent validation sets. In most cases, Local and ANN models, but not modified PLS, showed considerable improvement in the prediction of IVAL and SVAL after the calibration database had been expanded with the 10% samples of IVAL and SVAL reserved for calibration expansion. The effects of sample processing, instrument standardization and differences in reference procedure were partially confounded in the validation sets, so it was not possible to determine which factors were most important. Further work on the development of large databases must address the problems of standardization of instruments, harmonization and standardization of laboratory procedures and even more importantly, the definition of the database population.

• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.1
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• pp.102-112
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• 1999

The purpose of this study is to evaluate the effects of design criteria and environmental conditions of the site of created tidal flats on the structure and function of man-made ecosystem. Seven constructed tidal flats and three natural tidal flats were studied taking the difference in the location (wave height and tidal current), inflow of river water, slope of tidal flat and age after the construction completed into consideration. Parameters studied were physico-chemical and biological characteristics of soils and rate of respiration. The natural tidal flats had higher contents of silt, nitrogen and organic matter compared with the constructed ones. The natural ones had reductive zone below 2cm, whereas the constructed ones had aerobic zone from the surface to below 20cm. The bacterial population in the soil of the constructed tidal flats was one to two orders of magnitude lower than that in the natural ones. Both biomass of macrobenthos and microbial respiration rate, however, were not different significantly between the natural and the constructed tidal flats. There was an exceptional constructed tidal flat with similar physico-chemical and biological characteristics to the natural ones. It is most probable that sufficient conditions to have similar tidal flats to natural ones are the location in enclosed bay or calm coastal area. Thus, to make man-made tidal flats with the same characteristics as those in natural ones, man-made tidal flats should be designed and/or located to enhance the accumulation of silt on tidal flat. It is important to select a place having low water motion for construction of tidal flat.

• Journal of Life Science
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• v.30 no.10
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• pp.919-929
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• 2020

Aromatic compounds are widely used in the chemical, food, polymer, cosmetic, and pharmaceutical industries and are produced by mainly chemical synthesis using benzene, toluene, and xylene or by plant extraction methods. Due to many rising threats, including the depletion of fossil fuels, global warming, the strengthening of international environmental regulations, and the excessive harvesting of plant resources, the microbial production of aromatic compounds using renewable biomass is regarded as a promising alternative. By integrating metabolic engineering with synthetic and systems biology, artificial biosynthetic pathways have been reconstituted from L-tryptophan biosynthetic pathway in relevant microorganisms, such as Escherichia coli and Corynebacterium glutamicum, enabling the production of a variety of value-added aromatic compounds, such as 5-hydroxytryptophan, serotonin, melatonin, 7-chloro-L-tryptophan, 7-bromo-L-tryptophan, indigo, indirubin, indole-3-acetic acid, violacein, and dexoyviolacein. In this review, we summarize the characteristics, usage, and biosynthetic pathways of these aromatic compounds and highlight the latest metabolic engineering strategies for the microbial production of aromatic compounds and suitable solution strategies to overcome problems in increasing production titers. It is expected that strain development based on systems metabolic engineering and the optimization of media and bioprocesses using renewable biomass will enable the development of commercially viable technologies for the microbial production of many aromatic compounds.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.662-673
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• 2019

Root-knot nematodes (RKNs) are among the most destructive plant-parasites worldwide, and RKN control has been attempted mainly using chemical nematicides. However, these chemical nematicides have negative effects on humans and the environment, thus necessitating the search for eco-friendly alternative RKN control methods. Here, we screened nematicidal lactic acid bacteria (LAB) isolated from kimchi and evaluated their efficacy as biocontrol agents against RKNs. Of 237 bacterial strains, Lactobacillus brevis WiKim0069 showed the strongest nematicidal activity against the second-stage juveniles (J2) of Meloidogyne incognita, M. arenaria, and M. hapla and inhibited the egg hatch of M. incognita. The culture filtrate of WiKim0069 had a pH of 4.2 and contained acetic acid (11,190 ㎍/ml), lactic acid (7,790 ㎍/ml), malic acid (470 ㎍/ml), and succinic acid (660 ㎍/ml). An artificial mixture of the four organic acids produced by WiKim0069 also induced 98% M. incognita J2 mortality at a concentration of 1.25%, indicating that its nematicidal activity was derived mainly from the four organic acids. Application of WiKim0069 culture filtrate suppressed the formation of galls and egg masses on tomato roots by M. incognita in a dose-dependent manner in a pot experiment. The fermentation broth of WiKim0069 also reduced gall formation on melon under field conditions, with a higher efficacy (62.8%) than that of fosthiazate (32.8%). This study is the first report to identify the effectiveness of kimchi LAB against RKNs and to demonstrate that the organic acids produced by LAB can be used for the RKN management.