• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.294-303
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• 2008

Squid jigging fishery is very important in that there are about 1,000 jigging vessels more than 10 tonnage and about 5,000 ones less than 10 tonnage in Korea. But the cost of oil which is used to light fishing lamps, goes significantly up to almost one hundred million won for 50 tonnage vessels and forty million won in case of vessels less than 10 tonnage. This cost has almost taken 40% of total fishing costs. That is, the fishing business condition of squid jigging fishery is recently in the very difficult situation. As oil price increases, the business condition of the fishery gets worse and worse. Therefore it is very urgent to develop an economical fishing lamp, to solve this problem of fishery's business difficulty. This research aims at developing a fishing lamp for squid jigging fishery using the light emitting diode which has very excellent efficiency and durability. We made a water tank with 20 meters width which is a shape of raceway to research behavioral characteristics of Japanese flying squid to LED light, and made an experiment to investigate optimum wave of LED light to lure squid. The method is to establish LED lamps on both ends of water tank and to observe squid's behavior. Colors and wave lengths of LED lamps, used in experiment, are red(634nm), yellow(596nm), green(523nm), blue(454nm) and white(454nm+560nm). In experiment for attractive capability of LED lamp to squids, Japanese flying squid are highly attracted to blue lamp and white lamp. However, they are dispersed to red and yellow lamps. In addition, Japanese flying squid have moved and stayed in both dark ends of water tank. When compared intermittent lamp with continuous lamp, Japanese flying squid are highly attracted to intermittent lamp when intermittent interval is 0.25 second.

• ALGAE
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• v.26 no.2
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• pp.109-140
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• 2011

Taylor's (1960) floristic treatment of the benthic marine algae of the tropical and subtropical western Atlantic and Wynne's (2011) "checklist: third revision" serve as benchmarks in a review of changes made in the past half-century period. There has been a great increase in the number of recognized taxa of red, brown and green algae at all taxonomic ranks: from 758 to 1,393 species, an increase of 84%; from 231 to 406 genera, an increase of 75%; and from 63 to 106 families, an increase of 68%. In regard to recognized infraspecific taxa, the increase was less dramatic, from 140 to 185, thus a 32% change in the 50-year period. This review addresses the question: What factors were responsible for this proliferation of taxa that are now recognized in this domain of the tropical and subtropical western Atlantic? The answer is that many reasons contributed to these changes. Foremost among these causes have been the advances in gene-sequencing technologies. Revised phylogenetic relationships have led to many genera being divided into more than one genus, as well as new families and orders being delineated. Numerous examples of cryptic species have been discovered by gene-sequence and DNA-bar coding studies. This trend is depicted by case studies. Examples of genera being divided are Galaxaura, Liagora and Laurencia. Tricleocarpa and Dichotomaria have been segregated from Galaxaura. Trichogloeopsis, Ganonema, Izziella, Yamadaella, and Titanophycus have been segregated from Liagora. Chondrophycus, Osmundea, Palisada, and Yuzurura have been segregated from Laurencia. Examples are given of other genera present in this region of the western Atlantic that have been split up. Many genera have increased in terms of the number of species now assigned to them. Taylor's (1960) treatment recognized only two species in Hypoglossum, whereas Wynne's (2011) checklist contained a total of 9 species of Hypoglossum. Taylor's account included only two species of Botryocladia, but this number had grown to 15 in Wynne's checklist. Examples of new genera and species occurring in the region of the western Atlantic are given, and examples of taxa being newly reported for this domain are provided. An increase in the number of phycologists in Latin and South America, exploration of previously unexplored regions, and the increasing use of SCUBA for collecting and at greater depths have all contributed to the increase in the number of algal taxa that are now recognized as occurring in the tropical and subtropical western Atlantic.

• Journal of Korean society of Dental Hygiene
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• v.10 no.2
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• pp.311-322
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• 2010

Objectives : Since the program about sodium lauryl sulfate that might cause oral dryness and taste change including oral tissue allergy was on the air, the ingredients of D.I.Y dentifrices without sodium lauryl sulfate have been sold in online shopping mall and ordinary people can make the dentifrices easily. But there have not been any reports about the effect of dental plaque removal and preference about D.I.Y dentifrices. Therefore, this study was designed as a pilot study which aimed to investigate the effect of dental plaque removal and prefernece about D.I.Y dentifrices. Methods : 6 subjects were collected to test the effect of dental plaque removal with D.I.Y dentifrices with written consent. They didn't brushed the teeth during 12 hours until the check-up time on the next day. The O'leary index was calculated in baseline, 1 minute, 2 minute, 3 minute after brusing with D.I.Y dentifrices and market dentifrices. The preference about D.I.Y dentifrices through self-administered questionnaire was surveyed in 51 subjects after using D.I.Y dentifrices. Results : 1. The market dentifrices could remove larger amount of dental plaque than D.I.Y dentifrices, but, it wasn't significant. 2. In feeling refreshment, the market dentifrices had more positive answers significantly. 3. In feeling taste change, the market dentifries had more duration of taste change significantly. 4. In feeling oral dryness, the market dentifrices had more duration of oral dryness after toothbrushing. but, it wasn't significant. 5. As a result about reviewing the dental journals about ingredients of D.I.Y dentirices, green tea, sodium carbonate, bamboo salt, propolis had each evidence. But, We could not find out the evidences of calculus adhesion by corn starch, preservative by napri, disinfectant of peppermint. Conclusions : Although we cannot find the difference of the effect of dental plaque removal between D.I.Y dentifrices and market dentifrices, and D.I.Y dentifrices have the merits of decrease of oral dryness and taste change, it was suggested to have another test about stability and safety of D.I.Y dentifrices for safety of the user of D.I.Y dentifrices.

• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.345-353
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• 2015

The aim of this study is to develop residue analysis method for fenoxanil, a MBI (melanin biosynthesis inhibitor) propionamide fungicide, had mainly been used to control rice blast, and disease of other crops, fruits, and vegetables by using GLC/NPD and GC/MS. Extraction with acetone and partition with n-hexane/dichloromethane (80/20, v/v) were performed from hulled rice, soybean, Kimchi cabbage, green pepper, and apple, then column clean-up with florisil was applied. Mean recoveries were 82.2%-109.1% with less than 7.2% of coefficients of variation and limit of quantitation was set at the concentration of 0.04 mg/kg from the five agricultural products through the determination by GLC/NPD equipped with DB-5 capillary column and single laboratory validation. As a confirmatory method, GC/MS selected ion monitoring (SIM) was set from m/z 125.0, 188.9, and 293.0. Developed method is expected to apply the single residue analysis of fenoxanil in agricultural products.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.4
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• pp.541-548
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• 2013

Purpose: Marrow stromal cells (MSCs) have been known for their potential to trans-differentiate into neural and glial cells in vitro and in vivo. To investigate the influence of the developing host environment on the survival and morphological and molecular differentiation, murine MSCs transplanted into the eye of Brazilian opossum (Monodelphis domestica). Methods: Enhanced green fluorescent protein (GFP) - expressing MSCs were transplanted into developing Brazilian opossums. Animals were allowed to survive for up to 4 weeks after transplantation, at which time the eyes were prepared for immunohistochemical analysis. Results: Some transplanted MSCs survived and showed morphological differentiation into neural cells with some processes within the host vitreous chamber. Some transplanted cells expressed class III ${\beta}$-tubulin (TuJ1, a marker for neuronal cells) or glial fibrillary acid protein (GFAP, a marker for glial cells) or Nestin (a marker for neural stem cells). In addition, some transplanted cells were located in ganglion cell layer but did not show morphological and molecular differentiation. Conclusions: Our result show that the most effective stage of development for transplantation into the retina was postnatal day 16, which retinas developmentally corresponded to postnatal day 4-5 days mouse retina based on cell differentiation and lamination patterns. The present findings suggest that the age of the host appears to play a key role in determining cell fate in vivo.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.209-215
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• 2009

This study was performed to produce the processing factors of pesticides in dried carrot. It is essential data for establishing the maximum residue limits (MRLs) of pesticides in dried carrot. The target pesticides were azinphos-methyl, chlorpyrifos, captan, endosulfan and triclorfon. These pesticides are included Korea's MRL list in carrot and USA's MRL list in dried foods. To infiltrate these pesticides up to each MRL level in carrot, the dipping test was performed in laboratory. Also, the supervised residue trial of the pesticide for carrot was conducted in the green house to recognize the field trial's tendency. In the dipping test in laboratory (including drying examination), the processing factors of the carrot at various concentrations and temperatures could be evaluated. In field test, the processing factors were 5.9 for azinphos-methyl, 1.7 for captan, 7.6 for chlorpyrifos, 6 for endosulfan, 0 for trichlorfon, respectively. The dipping test in laboratory on various kinds of conditions showed more precise processing factors than field trial. The processing factors obtained from the dipping test of carrot were 0~4.7 at the various concentration of the pesticides, and 0~6.7 at various drying temperature. The lower level processing factors were 0~0.6 for trichlorfon and the higher level were 3.0~5.8 for chlorpyrifos. The highest processing factor was 9.1 for captan.

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.84-93
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• 2013

Validated analytical methods for isopyrazam are meager or lacking. In the present study, a single residual analytical method was developed for isopyrazam in selected commodities. Isopyrazam was analyzed in brown rice, soybean, green pepper, mandarin, cucumber, and Korean melon. We tried different solvents and methods through extraction, partition and purification steps to obtain best analytical results. For isopyrazam samples were extracted with acetonitrile, concentrated and partitioned with n-hexane, clean-up using florisil with n-hexane/ethylacetate (70/30) and analyzed with HPLC/UVD. The limit of quantitation (LOQ) for isopyrazam was 1.0 ng (S/N > 10) and method LOQ (MLOQ) was 0.04 mg $kg^{-1}$. Recovery ranged through 81.0~105.3% (syn-isomer) and 80.8~105.6% (anti-isomer) at fortification level of 0.04 (MLOQ), 0.4 (10 ${\times}$ MLOQ), and 2.0 (50 ${\times}$ MLOQ). The coefficient of variation (CV) for isopyrazam was less than 10% regardless of sample types. These results were further confirmed with LC/MS, respectively. The proposed method is highly reproducible and sensitive and is suitable for routine analysis.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.75-83
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• 2017

The single residue analytical method was developed for determining fungicide pencycuron residues in various agricultural commodities with high-performance liquid chromatography (HPLC). Pencycuron residue was extracted with acetone from representative crops such as Korean cabbage, apple, brown rice and green pepper. After ethyl acetate/n-hexane partition and subsequent clean-up with silica gel chromatography, pencycuron residue was quantified by reversed phase HPLC with UV detection at 240 nm. The suspected residue of pencycuron was confirmed using selected-ion monitoring (SIM) LC/mass spectrometry (MS). Instrumental limit of quantitation (ILOQ) and method LOQ (MLOQ) were set at 2 ng and 0.02 mg/kg, respectively. Overall recoveries of pencycuron from different crop samples fortified at three levels (MLOQ, 10MLOQ, 100MLOQ) were 72~108%. This proposed method could be useful as official analytical method for quantification of pencycuron residues in agricultural commodities.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.149-159
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• 2011

Bentazone is benzothiadiazole group herbicide, and used to foliage treatment. This herbicide have already been widely used for cereals and vegetables planting in worldwide. This experiment was conducted to establish a determination method for bentazone residue in crops using HPLC-UVD/MS. Bentazone residue was extracted with acetone (adjusted pH 1 with phosphoric acid) from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover bentazone from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The bentazone was quantitated by HPLC with UVD, using a YMC ODS AM 303 ($4.6{\times}250$ mm) column. The crops were fortified with bentazone at 3 levels per crop. Mean recovery ratio were ranged from 82.0% for a 0.2 mg/kg in apple to 97.9% for a 0.02 mg/kg in Chinese cabbage. The coefficients of variation were ranged from 0.5% for a 0.02 mg/kg in soybean to 9.7% for a 0.02 mg/kg in Chinese cabbage. Quantitative limit of bentazone was 0.02 mg/kg in representative five crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of bentazone in agricultural commodities.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.125-133
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• 2011

Ametryn is used in USA, China, and Japan, but not introduced in Korea yet. So, MRL (Maximum Residue Level), and analytical method of ametryn were not establishment in Korea. Therefore, this experiment was conducted to establish a determination method for ametryn residue in crops using HPLC-UVD/MS. Ametryn residue was extracted with acetone from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover ametryn from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The ametryn was quantitated by HPLC with UVD, using a Tosoh ODS 120T ($4.6{\times}250$ mm) column. The crops were fortified with ametryn at 2 levels per crop. Mean recovery ratio were ranged from 83.7% for a 0.2 mg/kg in soybean to 91.1% for a 1.0 mg/kg in hulled rice. The coefficients of variation were ranged from 1.2% for a 1.0 mg/kg in hulled rice to 3.6% for a 1.0 mg/kg in soybean. Quantitative limit of amatryn was 0.02 mg/kg in representative 5 crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of ametryne in agricultural commodities.