• Food Science of Animal Resources
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• v.30 no.2
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• pp.277-285
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• 2010

The objective of this study was to manufacture spent layer chicken meat products by natural freeze-drying. The spent layers of chickens that were slaughtered at 80 wk were obtained from a local slaughter house and separated into two halves of carcasses. The samples were divided into the following groups: 1) control (non-curing), 2) curing, and 3) curing with 2% trehalose before drying. The cured meats were placed at $2^{\circ}C$ for 7 d and then transferred to a natural drying spot located in Injae City, Gangwondo, Korea. The experiment was conducted from January to March in 2008. The average temperature, RH, and wind speed were $-1.5^{\circ}C$, 63%, and 1.8 m/sec, respectively. The cured treatments showed higher pH, lower Aw and lower shear force value compared with the control. Based on the results of TBARS (2-thiobarbituric acid reactive substances) level and volatile basic nitrogen value, lipid oxidation and protein deterioration were inhibited in curing treatments during drying. Trehalose acted as a humectant because it maintained a lower water activity despite the relatively higher moisture content during drying. The polyunsaturated fatty acids content and sensory attributes were higher in cured treatments than in the control during drying. Most of the bacterial counts in the treated groups were lower by 2 Log CFU/g after 1 mon of drying, and Salmonella spp. and Listeria spp. were not found in any treatment. There was also no microbial safety problem associated with dried meat products. Based on the results of this experiment, dried meat products could be manufactured from precured spent layer chickens by natural freeze-drying during winter.

• Journal of the Korean Arthroscopy Society
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• v.14 no.3
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• pp.180-187
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• 2010

Purpose: Rotator cuff tears involving the subscapularis are less common than those involving the superior and posterior rotator cuff. The purpose of the present study was to report the clinical results of repair of isolated traumatic tears of the subscapularis tendon. Materials and Methods: Fifteen patients (13 males, 2 females; mean age 46.2 years; range 35 to 52) with unilateral ruptures of the subscapularis tendon after trauma who underwent arthroscopic repair between February 2003 and October 2008 were reviewed retrospectively. All the cases were isolated tears of the subscapularis without the involvement of any other rotator cuff tendon and were followed for at least two years (mean 28 months). The entire subscapularis was involved in 9 cases and the tear was localized to the upper two thirds in 6 cases. The preoperative and postoperative status of patients with isolated subscapularis tears were analyzed using the Constant Score, American Shoulder and Elbow Society Index (ASES Index) and postoperative integrity was determined through magnetic resonance imaging. Results: The average clinical outcome scores and strength were all improved significantly at the time of the final follow-up. The constant shoulder score improved from 41.5 to 81.3 points (P<0.05) compared to before surgery and ASES index improved from 46.4 to 89.6 points (P<0.05) postoperatively. Thirteen patients (87%) were satisfied with the result of the treatment. The total tears were significantly more improved by surgery than the partial tears. In 12 of 15 patients (80%) were judged to reveal healed tendon on magnetic resonance imaging at a mean of 13 months postoperatively. The postoperative score was significantly lower for the patients with a failed repair than it was for those with an intact repair (P<0.05). Conclusion: Repair of traumatic isolated subscapularis tears through arthroscopic techniques effectively restores patient function with regard to pain, mobility, strength and postoperative tendon integrity. The postoperative integrity of the repair correlates with the functional results and the total tears were more improved by surgery than the partial tears, but future studies may be needed.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.8-9
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• 2011

On 4 September 2010 an earthquake of magnitude 7.1 on the Richter scale occurred on the Canterbury Plains in the South Island of New Zealand. The Canterbury Plains are an area of extensive groundwater and spring fed surface water systems. Since the September earthquake there have been several thousand aftershocks (Fig. 1), the largest being a 6.3 magnitude quake which occurred close to the centre of Christchurch on 22February 2011. This second quake caused extensive damage to the city of Christchurch including the deaths of 189 people. Both of these quakes had marked hydrological impacts. Water is a vital natural resource for Canterburywith groundwater being extracted for potable supply and both ground and surface water being used extensively for agricultural and horticultural irrigation.The groundwater is of very high quality so that the city of Christchurch (population approx. 400,000) supplies untreated artesian water to the majority of households and businesses. Both earthquakes caused immediate hydrological effects, the most dramatic of which was the liquefaction of sediments and the release of shallow groundwater containing a fine grey silt-sand material. The liquefaction that occurred fitted within the empirical relationship between distance from epicentre and magnitude of quake described by Montgomery et al. (2003). . It appears that liquefaction resulted in development of discontinuities in confining layers. In some cases these appear to have been maintained by artesian pressure and continuing flow, and the springs are continuing to flow even now. In spring-fed streams there was an increase in flow that lasted for several days and in some cases flows remained high for several months afterwards although this could be linked to a very wet winter prior to the September earthquake. Analysis of the slope of baseflow recession for a spring-fed stream before and after the September earthquake shows no change, indicating no substantial change in the aquifer structure that feeds this stream.A complicating factor for consideration of river flows was that in some places the liquefaction of shallow sediments led to lateral spreading of river banks. The lateral spread lessened the channel cross section so water levels rose although the flow might not have risen accordingly. Groundwater level peaks moved both up and down, depending on the location of wells. Groundwater level changes for the two earthquakes were strongly related to the proximity to the epicentre. The February 2011 earthquake resulted in significantly larger groundwater level changes in eastern Christchurch than occurred in September 2010. In a well of similar distance from both epicentres the two events resulted in a similar sized increase in water level but the slightly slower rate of increase and the markedly slower recession recorded in the February event suggests that the well may have been partially blocked by sediment flowing into the well at depth. The effects of the February earthquake were more localised and in the area to the west of Christchurch it was the earlier earthquake that had greater impact. Many of the recorded responses have been compromised, or complicated, by damage or clogging and further inspections will need to be carried out to allow a more definitive interpretation. Nevertheless, it is reasonable to provisionally conclude that there is no clear evidence of significant change in aquifer pressures or properties. The different response of groundwater to earthquakes across the Canterbury Plains is the subject of a new research project about to start that uses the information to improve groundwater characterisation for the region. Montgomery D.R., Greenberg H.M., Smith D.T. (2003) Stream flow response to the Nisqually earthquake. Earth & Planetary Science Letters 209 19-28.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.59-66
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• 2011

This study was conducted to investigate the effect of vase material and floral preservative treatment over time on flower color, leaf color and flower size of cut flowers Rosa hybrida 'Aqua' and 'Corvernet', and Gerbera jamesonii 'Honeymoon' and 'Golden Time' stuck in a glass, porcelain, or onggi (pottery with a dark bronze glaze) vase containing either tap water or a floral preservative solution. The ${\Delta}E$ values in flower color of 'Aqua' rose at 8 days after treatment with a floral preservative in onggi and porcelain vases were low. The ${\Delta}E$ value of 'Covernet' rose treated with floral preservative in an onggi vase was the lowest and L value was the closest to that of petals of cut flowers at just before treatment (control). The ${\Delta}E$ value of 'Honeymoon' gerbera treated with a floral preservative in an onggi vase was the lowest and a value of 58.81 and b value of 34.29 were the closest to that of the control group as color of cut flowers in an onggi vase was similar to the color at the beginning of treatment. The ${\Delta}E$ value of 'Golden Time' gerbera treated in an onggi vase was significantly lower than that in a porcelain or glass vase and a value of -7.81 treated with a floral preservative solution in an onggi vase was the closest to the control and b value was high in an onggi vase as well. The L, a, and b values in leaf color of roses were similar to each value of the control and ${\Delta}E$ value of 3.25 measured in an onggi vase was lower than that in a porcelain or glass vase. Flower diameter of 'Covernet' and 'Golden Time' roses treated with a floral preservative in an onggi vase was greater than that in other treatments. From these results, the floral preservative applied to a holding solution is assumed to improve the quality and freshness of cut roses and gerberas by inhibiting microbes propagation and by promoting uptake of water and nutrients. The onggi vase with fine pores will promote the expression and maintenance of flower and leaf colors and may increase flower diameter by high air permeability.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.413-420
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• 2019

In this study, a sample preparation method and a simultaneous determination method by ultra-high performance liquid chromatography coupled with tandem mass spectrometry for 9 isomers of chlorogenic acid and arbutin in fruits were developed. The samples were extracted using 90% methanol (pH 3.0), with the solutions being shaken and then sonicated for 10 min each. After centrifugation at 4,000 rpm for 10 min, the extraction was concentrated under a vacuum at $40^{\circ}C$ using a vacuum evaporator. The residue was dissolved in 5 mL of 5% methanol and filtered through a $0.45{\mu}m$ membrane before UHPLC-MS/MS analysis. The separations were performed on a C18 column with gradient elution of water (containing 0.1% formic acid) and methanol (containing 0.1% formic acid). The specificity, linearity, limit of detection, limit of quantification, accuracy, and precision of the proposed methods were also evaluated.

• Food Science and Preservation
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• v.15 no.5
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• pp.743-748
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• 2008

Amyloid $\beta$ peptide ($A{\beta}$) is known to increase oxidative stress in nerve cells, leading to apoptosis that is characterized by free radical formation and lipid peroxidation. Neurodegenerative diseases such as Alzheimer's disease (AD) are characterized by large deposits of $A{\beta}$ in the brain. In our study, neuronal protective effects of green tea, along with water activity (0.813), and leaf storage periods (fresh leaf, or leaf stored for up to 4 weeks) were investigated. We measured protective effects against $A{\beta}$-induced cytotoxicity in neuron-like PC12 cells. Powdered green tea was extracted with distilled water at $70^{\circ}C$ for 5 min, and this extract was freeze-dried and stored at $-20^{\circ}C$ until use. In cell viability assays using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), the fresh extract, and that obtained after 1 week of leaf storage, showed the best protective effects against $A{\beta}$-induced neurotoxicity. As oxidative stress causes membrane breakdown, the protective effect of green tea extracts was investigated using lactate dehydrogenase (LDH) and trypan blue exclusion assays. LDH release into the medium was inhibited (by 20-25%) in all tests. In addition, all green tea extracts (fresh, or stored before extraction for up to 4 weeks) showed better cell protective effects ($93.3{\pm}1.8-96.2{\pm}2.4$) than did vitamin C ($91.0{\pm}1.6$), used as a positive control. The results suggest that effectiveness of green tea extracts falls with prolonged leaf storage.

• Korean Journal of Remote Sensing
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• v.37 no.6_2
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• pp.1859-1867
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• 2021

This study investigated seasonal characteristics of the particulate matter (PM) in the atmosphere and rainwater quality in Busan, South Korea, and evaluated the seasonal effect of PM₁₀ concentration in the atmosphere on the rainwater quality using multivariate statistical analysis. The concentration of PM in the atmosphere and meteorological observations(daily precipitation amount and rainfall intensity) are obtained from automatic weather systems (AWS) by the Korea Meteorological Administration (KMA) from March 2020 to August 2020. Rainwater samples (n = 216, 13 rain events) were continuously collected from the beginning of the precipitation using the rainwater collecting device at Pukyong National University. The samples were analyzed for pH, EC (electrical conductivity), water-soluble cations(Na⁺, Mg²⁺, K⁺, Ca²⁺, and NH₄⁺), and anions(Cl^-, NO₃^-, and SO₄^2-). The concentration of PM₁₀ in the atmosphere was steadily measured before and after the precipitation with a custom-built PM sensor node. The measured data were analyzed using principal component analysis (PCA) and Pearson correlation analysis to identify relationships between the concentration of PM₁₀ in the atmosphere and rainwater quality. In spring, the daily average concentration of PM₁₀ (34.11 ㎍/m³) and PM_2.5 (19.23 ㎍/m³) in the atmosphere were relatively high, while the value of daily precipitation amount and rainfall intensity were relatively low. In addition, the concentration of PM₁₀ in the atmosphere showed a significant positive correlation with the concentration of water-soluble ions (r = 0.99) and EC (r = 0.95) and a negative correlation with the pH (r = -0.84) of rainwater samples. In summer, the daily average concentration of PM₁₀ (27.79 ㎍/m³) and PM_2.5 (17.41 ㎍/m³) in the atmosphere were relatively low, and the maximum rainfall intensity was 81.6 mm/h, recording a large amount of rain for a long time. The results indicated that there was no statistically significant correlation between the concentration of PM₁₀ in the atmosphere and rainwater quality in summer.

• 기호학연구
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• no.57
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• pp.91-120
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• 2018

This study was contemplated about an aspects of modernity that was discovered of ImcheonByeolgok(林川別曲) written by Okgukjae Lee, Un-young in 18th Century. It was composed time that unprecedented state in the 18th century. So, I considered that Modernity was the most appeared at 18th Century. During this period, Changes has happened in ideology and system in terms of politics, economy, society and culture. This change is the beginning of a new modern consciousness. There is also a tendency to think of Imcheonbyeolgok as the autobiographical story of Lee, Yun-young. It seems that Lee, Yun-young has a progressive scholarly thought, but he did not reveal his own situation by insulting him. Therefore, I am not realistically valid for being able to see it as an autobiographical story that he actually experienced. Also, although ImcheonByeolgok is known as a love song, it is hard to see it as a love song because its satirical features are strong. and It is characterized by the peculiar form of narrative being described as a dialogue. I picked two aspects of modernity in ImcheonByeolgok. One is resistance to love and desire, and the other is disintegration of the order of identity. The two aspects of this paper were presented as Greimas's Actant Model. ImcheonByeolgok is the result of efforts to show the changing modern Joseon Dynasty's elements in the form of resistance and resistance to Joseon's feudal society, such as Confucian ideology and identity systems. Thus, I suggested the corrupt ruling class of Joseon's feudal society and the exploited working class life as an old living and a grandmother instead of 'resistance' and 'disposal' in the 18th century. The criticism of traditional feudal societies that emerged in the 18th century turned out to be a hegemony that distinguishes the Middle Ages from the Modern Age, which resulted in differences between the ages before and after the 18th century. Although these hegemony were not clearly distinguished in household literature in the 18th century, it was established and developed in the 19th century. I suggested that Lim's Star Song was an important work that played an important role in bringing about this change.

• Pediatric Infection and Vaccine
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• v.25 no.3
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• pp.123-131
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• 2018

Purpose: Cytomegalovirus (CMV) infection is mostly asymptomatic but can be detrimental to certain hosts. We investigated changes of CMV seroprevalence in Koreans before and after the year 2000. Methods: We reviewed laboratory values of patients who were tested for CMV immunoglobulin G (IgG) at Samsung Medical Center, Seoul, Korea, from January 1995 to December 2015. Changes in seroprevalence were analyzed by gender, age, region, and tested year period (period 1, 1995-2005 vs. period 2, 2006-2015). Results: Overall CMV seropositivity was 94.1% (10,900/11,584). There was no significant difference for CMV seropositivity among the two periods (94.2% vs. 94.1%) (P=0.862). CMV seropositivity in the 11 to 20-year age group in period 2 (78.8%) was significantly lower than that of period 1 (89.9%) (P=0.001). The seropositivity of individuals aged 31-40 years (97.4%) was significantly higher than that of younger age groups (P<0.001) and lower than that of older age groups (P<0.001). Of 2,441 females of reproductive age (from 15 to 49), CMV seropositivity was 97% (2,467/2,441). The seropositivity in women aged 20-24-years was higher than that of men in the same age group (97.6% vs. 85.6%, P=0.003). No significant difference was observed among different regions. Conclusions: Overall CMV seropositivity of Koreans was estimated to be 94% and the average seropositivity of reproductive women was 97%. Monitoring of the changes in seroprevalence including the reproductive age group is needed in the future.

• Economic and Environmental Geology
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• v.52 no.3
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• pp.223-230
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• 2019

The calcination of oyster shells have been studied as the possible substitute for the limestone used as an absorbent of $SO_2$ gas. However, since pure shells can not be used in calcination process, some impurities are contained and the changes in the characteristics of the calcination products are expected. In this study, the surface characteristics of the calcination products are investigated by mineralogical analysis according to the contents of NaCl, which can be derived from sea water, and sediments on the surface of the shell as impurities. The marine sediments on the shells were mainly composed of quartz, albite, calcite, small amounts of amphibole and clay minerals such as ilite, chlorite and smectite. After calcination of oyster shells mixed with 0.2-4.0 wt% sediments at $900^{\circ}C$ for 2 hours, regardless of the dehydration, dehydroxylation, and phase change of these minerals at the lower temperature than this experiment, no noticeable changes were observed on the specific surface area of the calcined product. However, when mixed with 0.1 to 2.0 wt% NaCl, the specific surface area generally increases as compared with the shell sample before calcination. The specific surface area increases with increasing amount of salt, and then decreases again. This is closely related to the changes of surface morphology. As the amount of NaCl increases, the morphology of the surface is similar to that of gel. It changes into a slightly angular, smaller particle and again looks like gel with increasing amount of NaCl. Our results show that NaCl affects morphological changes probably caused by melting of some oyster shells, but may have different effects on the specific surface area of calcination product depending on the NaCl contents.