• Analytical Science and Technology
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• v.32 no.6
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• pp.243-251
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• 2019

Microplastics (MP) are found in large quantities in the oceans, posing a major threat to the ecosystem. In Korea, MPs have been reported to be detected in sea salts. In order to analyze MPs, information on their composition, size, and shape is required. FT-IR microscopy is used frequently to measure sizes larger than 20 ㎛. Recently, however, Raman microscopy, which can analyze ultrafine plastics below 20 ㎛, has been applied extensively. In this study, 10.0 g samples of commercially available salts were dissolved and filtered through a 45 ㎛ mesh filter with a size of 25.4 mm × 25.4 mm. These filtered samples were then analyzed by both FT-IR microscopy and Raman microscopy. A total of four MPs, including three polyethylene (PE) of size 70-100 ㎛ and a polypropylene (PP) of size 170 ㎛, were detected by FT-IR microscopy, while 10 MPs, including nine PE of size 10-120 ㎛ and one polystyrene (PS) of size 40 ㎛, were detected by Raman microscopy. Approximately, 1,000 MPs/kg was estimated, which was almost two times higher than the previous reported levels (~550-681 particles/kg in sea salts); this is because Raman microscopy can detect much smaller MPs than FT-IR microscopy. A total of 113 particles were found using Raman microscopy: Carbon (35, 31.5 %), minerals (28, 25 %), and glass (16, 14.4 %) were dominant, forming around 70% of the total, but MPs (10, 8.8 %) and cellulose (5, 4.5 %) were also found. Raman microscopy has great potential as an accurate method for measuring MPs, as it can measure smaller size MPs than FT-IR microscopy. It also has a reduced sample preparation time.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.9-16
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• 2010

A previous study has shown that the g.17924G>A polymorphism of fatty acid synthase (FASN) is associated with unsaturated fatty acid composition in the Hanwoo beef, hence this study was conducted to evaluate the effect of single nucleotide polymorphisms (SNPs) within FASN gene on the selection phenotypes of Hanwoo breeding stock. A total of 925 progeny test steers were used to genotype g.11280G>A, g.13125T>C, and g.17924G>A polymorphisms and significant associations were found among g.11280G>A, g.17924G>A, and carcass traits, such as carcass weight, backfat thickness, and beef quantity index. No significant association was found between g.13125T>C and carcass traits. Although the degree of linkage disequilibrium (LD) was not strong among g.11280G>A, g.13125T>C, and g.17924G>A in the LD analysis, four major haplotype classes were formed with the genotypic information within the FASN gene; the frequencies of the halpotypeswere -GCG-[0.378], -ATG-[0.301], -GTA-[0.191], and -ACG-[0.063], respectively. Phenotypic association was performed among these haploptypes, and the haplotype 2 (-ATG-)was significantly associated with higher carcass weight when compared to the other haplotypes, i.e. haplotype 1 (-GCG-) and haplotype 3 (-GTA-). A copy number of the FASN haplotype 3 (-GTA-) had also a significant association with carcass weight of subjects. In conclusion, it was observed that two polymorphisms (g.11280G>A and g.17924G>A) and their haplotypes within the FASN gene are consistently associated with carcass traits. Therefore, it is desirable to use the FASN polymorphisms for pre-selection program as genetic marker with improved carcass yield and beef quality of the Hanwoo sire at the Hanwoo Improvement Center as well as for commercial Hanwoo producers, the FASN genotypic information can be used for a part of selecting Hanwoo dam for superior calf production.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.665-676
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• 2003

To investigate the chemical characteristics of PM$\_$2.5/ in Seoul, Korea, atmospheric particulate matters were collected using a PM$\_$10/ dichotomous sampler including PM$\_$10/ and PM$\_$2.5/ inlet during the period of October 2000 to September 2001. The Inductively Coupled Plasma-Mass Spectromety (ICP-MS), ion Chromatography (IC) methods were used to determine the concentration of both metal and ionic species. A statistical analysis was performed for the heavy metals data set using a principal component analysis (PCA) to derived important factors inherent in the interactions among the variables. The mean concentrations of ambient PM$\_$2.5/ and PM/sub10/ were 24.47 and 45.27 $\mu\textrm{g}$/㎥, respectively. PM$\_$2.5/ masses also showed temporal variations both yearly and seasonally. The ratios of PM$\_$2.5/PM$\_$10/ was 0.54, which similar to the value of 0.60 in North America. Soil-related chemical components (such as Al, Ca, Fe, Si, and Mn) were abundant in PM$\_$10/, while anthropogenic components (such as As, Cd, Cr, V, Zn and Pb) were abundant in PM2s. Total water soluble ions constituted 30∼50 % of PM$\_$2.5/ mass, and sulfate, nitrate and ammonium were main components in water soluble ions. Reactive farms of NH$_4$$\^$+/were considered as NH$_4$NO$_3$ and (NH$_4$)$_2$SO$_4$ during the sampling periods. In the results of PCA for PM$\_$2.5/, we identified three principal components. Major contribution to PM$\_$2.5/ seemed to be soil, oil combustion, unidentified source. Further study, the detailed interpretation of these data will need efforts in order to identify emission sources.

• The Journal of Engineering Geology
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• v.22 no.1
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• pp.95-111
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• 2012

This study investigated the relationship between the geochemical environment and the occurrence of natural radioactive materials (uranium and Rn-222) in borehole groundwater at an Icheon site. The drill core recovered from the study site consists mainly of biotite granite with basic dykes. The groundwater samples were collected at four different depths in the borehole using the double-packed system. The pH range of the groundwater was 6.5~8.6, and the chemical type was Ca-$HCO_3$. The ranges of uranium and Rn-222 concentrations in the groundwater were 8.81~1,101 ppb and 5,990~11,970 pCi/L, respectively, and concentrations varied greatly with depth and collection time. The ranges of uranium and thorium contents in drill core were 0.53~18.3 ppm and 6.66~17.5 ppm, respectively. Microscope observations and electron microprobe analyses revealed the presence of U and Th as substituted elements for major composition of monazite, ilmenite, and apatite within K-feldspar and biotite. Although the concentration of uranium and thorium in the drill core was not high, the groundwater contained a high level of natural radioactive materials. This finding indicates that physical factors, such as the degree of fracturing of an aquifer and the groundwater flow rate, have a greater influence on the dissolution of radioactive materials than does the geochemical condition of the groundwater and rock. The origin of Rn-222 can be determined indirectly, using an interrelationship diagram of noble gas isotopes ($^3He/^4He$ and $^4He/^{20}Ne$).

• Health Policy and Management
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• v.2 no.1
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• pp.42-65
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• 1992

To survey the specialties or sujects of practice displayed by the private practitioners the authors visited 691 clinics in Taegu from April 1 to May 18, 1991, At the same time, a mail questionnaire was administered to ask the number of displayed subjects of practice, and the reasons for displaying the subjects, reasons for not displaying in case of no specialty was displayed, composition of patients, and role as a specialist. The questionnaire was returned by 308(44.6%) practitioners. The distributions of private practitioners by specialty were 13.9% for internal medicine (IM), 11.7% for pediatrics(Ped), 13.0% for obstetrics '||'&'||' gynecology(OBGY), 11.1% for general surgery(GS), 10.0% for family practice(FP), and 5.3% for general practitioner(GP). Ninety percent of the specialists have displayed their specialty in their offices. Among all the private practitioners, 61.9% of them have displayed their subjects of practice and 23.7% have shown telephone number. Among private practitioners who displayed the subjects of practice, 80.6% have signs of 'subjects of practice'. Mean number of the displayed subjects of practice for the all private practitioners is 1.20, and 1.93 for the private practitioners who displayed subjects of practice. FP and GS have displayed their subjects of practice in 91.2% and 87.0% respectively and OBGY have displayed in 32.2%, the lowest percentage among all the soecuaktues. IM specialists displays pediatrics as a major subject of practice in 72.1% the pediatricians display IM in 88.9% the OBGYs display pediatrics in 77.8%, and the GSs display IM in 51.9%. Most commonly displayed subjects of practice are Ped and IM. Sixty-five percent of the private practitioners answered that they don't display their specialties because their clinics are "primary health care facility". The reasons for displaying the subjects of practice and its relevance with their own specialty(45.6%), and the difficulty in clinic management only with the patients for their own specialty(36.9%). The proportion of clinics whose patients of other specialty are than their own specialty accounted less than 10% was 52.8% and that accounted more than 51% was 16.0%. Specially, 51.4% of GS specialists cared more than 51% of patients of other specialty area than their own specialty. Most of the patients of IM, Ped, and OBGY specialists are the patients of their own specialty. However, 56.8% of GS care more of IM patients and only 24.3% of them care mostly GS patients, The respondents to the mail questionnaire who stated that they can not play the role of specialist well are 30.5% and especially 72.9% of the GS specialists state so. The proportion of respondents who do not suffort the private practice of specialists is 71.1%. Among the surgical specialists, 82.7% of them rarely perform operation. The reasons for not performing operation are insufficient insurance fee (76.9%), and risk of operation(58.0%), so as the OBGY specialists. Above finidngs suggest that most of the specialists, especially surgeons, in the private practice can not play their role as a specialist. It is necessary to develop a policy that facilitates the production of practice and the retention of the specialists in the hospitals.s.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.447-455
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• 2011

To investigate the effects of the improvement of postharvest quality on fresh tomato, antimicrobial microperforated (AMP) films were prepared and their antimicrobial abilities were observed. AMP films were made by coating different types of natural antimicrobial agents such as cinnamon, clove, and clary sage essential oils into microperforated (MP) films. Cinnamon essential oil of 10% (v/v) has proven to be very effective as inhibitor of the mold growth on tomato, compared to the clove and clary sage essential oils. Quality changes of fresh tomatoes packed using the natural AMP films (AMP10 and AMP30) and MP films (MP10 and MP30) during storage were evaluated. Total microbial growth, weight loss, firmness, lycopene content, and decay rate as the major quality parameters were monitored over 9 days at $15^{\circ}C$. The oxygen transmission rates and mechanical properties between the natural AMP and MP films were also compared. There was no significant difference in change of oxygen transmission rate, tensile strength and elongation between the AMP and MP films. For storage studies, the freshness of tomato packaged in AMP30 film was higher than that in OPP film (the control), MP10, MP30, and AMP10 films. Especially, AMP30 film exhibited high efficiency compared to the control for tomato decay during storage periods. Based on the results, the microperforation and antimicrobial properties of the packaged films may significantly affect the maintenance of an optimum gas composition within the package atmosphere for increasing the storage life and quality of produce. They were also effective on the inhibition of microbial growth by controlled release of antimicrobial agent at an appropriate rate from the package into the tomato. Natural antimicrobial agent coating microperforated films could use potential functional package as a method of extending the freshness of postharvest tomato for storage.

• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.356-367
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• 2012

Community structure of fish and inhabiting status of endangered species, Cobitis choii and Gobiobotia naktongensis were investigated in the Ji Stream, a tributary of the Geum River Drainage System of Korea from May to October 2011. Ten to 23 fish species inhabited upper stream (St. 1~St. 4) with a Aa-Bb river type composed of mostly pebble and cobble bottoms, 16~28 species did middle stream (St. 5~St. 7) with a Bb type composed of mostly cobble and boulder bottoms, and 20-29 species did lower stream (St. 8~St. 10) with a Bb-Bc type composed of mostly sand bottoms. A total of 44 species belonging to nine families were found in the stream during the survay. The dominant species were in the order of Zacco platypus (37.2%), Pungtungia herzi (5.8%) and Pseudogobio esocinus (5.5%). Other abundant species included Acheilognathus lanceolatus (5.3%), Zacco koreanus (5.2%), Hemibarbus longirostris (4.9%) and Squalidus gracilis majimae (3.5%). Among residing species, 16 species were endemic to Korea, two (Cobits choii and Gobiobotia naktongensis) were endangered, and one (Micropterus salmoides) was non-indigenous. The similarity index based on species composition and abundance clearly delineated the fish community of the Ji Stream according to the three major sections, which were defined at the above. Dominance index gradually decreased toward downstream, while diversity, evenness and species richness indexes gradually increased toward downstream. The two endangered species, C. choii and G. naktongensis co-occurred at the lower stream due to the prevalence of a sandy substratum.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.192-197
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• 2011

Rice spent water (RSW) is generated when rice is rinsed before cooking. RSW has been discarded into sewerages due to its low usage in our daily life and become a major domestic wastewater for many years. But RSW can be used as a value-added resource because it contains various beneficial bioactive components. Therefore, fermented rice spent water (FRSW) has been already produced in our previous value-added fermentation process. In this study, proximate compositions and contents of other typical fermentation products were compared between RSW and FRSW. Both RSW and FRSW contain approximately 99.3% moisture and 0.7% total solids. Compared to those of RSW on a dry basis, carbohydrate content of FRSW was decreased by 44.8% and crude protein, lipid, and ash contents of FRSW were increased by 16.4%, 18.8%, and 36.6%, respectively. In addition, starch granules of RSW were intact as those of rice flour were, but those of FRSW were not. RSW did not have lactic acid, but FRSW had 212.13 and 181.25 g/kg D- and L-lactic acid, respectively. Free amino and ammoniacal nitrogen contents of FRSW were 12 and 7 times higher than those of RSW, respectively. Lactic acid, free amino, and ammonical nitrogen contents were considered to be increased in FRSW because carbohydrates could be disintegrated into lactic acids and proteins into free amino or ammoniacal nitrogens during the fermentation process.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.496-502
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• 2004

The development of sesame varieties which contain high contents of lignan compounds has been progressed in Korea. This study was carried out to get the basic information for the breeding of high quality sesame varieties and the development of health functional food sources using lignan compounds from sesame. The contents of sesamin and sesamolin were $4.08\pm1.74$ and $2.47\pm0.68mg/g$, respectively, from sesame cultivated in 2002 and those were $4.08\pm1.51$ and $2.48\pm0.69mg/g$, respectively, from sesame cultivated in 2003. The content of sesamine was high in the order of Danbaek (6.22 mg/g), Seongbun (5.94 mg/g), Namda (5.83 mg/g), and Naman (5.59 mg/g) producted in 2002 and Seongbun (6.27 mg/g), Dasak (5.53 mg/g), Danbaek (5.50 mg/g), chinbaek (5.45 mg/g), and Seodun (5.41 mg/g) producted in 2003. The content of sesmoline was high in the order of Hwangbaek (3.27 mg/g), Seongbun (3.26 mg/g), Annam (3.22 mg/g), Hanseom (3.17 mg/g), and Danbaek (3.16 mg/g) producted in 2002, and Seongbun (3.21 mg/g), Seodun (3.14 mg/g), Pungan (3.10 mg/g), Naman (3.09 mg/g), and Danbaek (3.04 mg/g) producted in 2003. The contents of sesamin and sesamolin of Yangbaek, which has used as a standard variety for sesame breeding, were relatively lower than in any other varieties. These resluts suggest that Yangbaek is not the proper variety as a standard variety for development of high quality sesame. In conclusion, proper good variety as a standard variety for sesame breeding must be determined after careful consideration on the major quality factors including crude oil and lignan compounds as well as agricultural characteristics to develop high quality sesame varieties containing high contents of lignan compounds.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.393-408
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• 2018

This study was carried out to investigate how chlorella dry powder added to the feed of laying hens influences on the egg quality and the composition of egg yolk's fatty acid. Moisture content, ash content, crude protein content, and crude fat content were 12.8%, 10.8%, 18.0% and 2.5%, respectively. The moisture content of the chlorella powder added to the feed was about 1.54%, the ash content was 6.53%, the crude protein content was 54.56%, and the crude fat content was 2.45 %. After feeding chlorella, compared to the control, the color of egg shell significantly became darker. The hardness of egg shell was increased for 10 days after chlorella feeding and was significantly strengthened. Thickness of egg shell was significantly thicker. The height of egg whites was increased. After 10 days of providing chlorella, the quality of egg white was 92.0 HU (Haugh Unit), which was significantly higher than 84.8 HU, the quality of the control. The color of egg yolk significantly revealed more yellow than that of the control. Egg weight was increased by 7.5% after 15 days of feeding chlorella. Protein content was increased by 11.9% and 10.7% after 10 and 15 days of feeding, respectively. The major compositions of fatty acid content of egg yolk fed with chlorella diet were oleic acid, trans-linoleic acid, palmitic acid, ${\alpha}$-linolenic acid, stearic acid, DHA, EPA, palmitoleic acid, and heptadecanoic acid, respectively. Palmitoleic acid was decreased in the eggs fed with chlorella diet compared to the control. The Saturated Fatty Acid (SFA) content of the control was higher than that of the eggs fed with chlorella. The content of Unsaturated Fatty Acid (UFA) was higher in egg yolks fed with chlorella than in the control. The ratio of UFA to Saturated Fatty Acid (SFA) was higher in egg yolks fed with chlorella than in the control. These results suggest that the addition of chlorella to the feed of the laying hens brings positive effects on the improvement of egg quality and lowering of the Unsaturated Fatty Acid of egg yolk.