• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.4
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• pp.270-282
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• 2012

This study was conducted to investigate the impact of sand addition to an intertidal for the development of the Manila clam habitat on benthic community structure. For this, we focused on the spatio-temporal changes in the surface sediment condition and benthic community structure before and after the event. Study site was an sandbank in Gonam-myeon, Taean-gun where sand added to on July 2010. We set three stations at each of sand adding area (experimental plot) and non sand-adding area (control plot) and did sampling works ten times from June 2010 to October 2011. Directly after the event, surface sediments changed to very coarse sand, but the state was not maintained over four months because of seasonal sedimentation and finally got back to very fine sand in eight months. The number of species and density were temporarily reduced right after the event and crustacean species such as Apocorophium acutum, Photis sp. were most negatively affected by the event. However, the number of species recovered from the reduction in three months and density did in four months due to the recolonization by the existing species and species in the vicinity of the plot. During the study period, dominant species continuously changed from the species such as A. acutum, Photis sp. at the time before the event, through the species such as Heteromastus filiformis, Macrophthalmus japonicus at the time right after the event, to the species such as Musculista senhousia, Ruditapes philippinarum, Mediomastus californiensis in the latter part of the study period. Although surface sediment properties and ecological indices recovered within a certain period after the event, the recovery of community structure has never been observed up to the end of the study.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.78-99
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• 2020

The Buddha triad and 16 Arhat statues carved on the rock surface at Seongbulsa temple is the only domestic remaining example of all 16 Arhats, so its academic value is very high. However, it is severely damaged and so required a stability evaluation through study of digital documentation and precise diagnosis for the purpose of comprehensive conservation. This process established that the Buddha statues were of similar scale, while the Arhats showed a wide variety of sizes, and the two kith and kin in the volume were larger than the Arhats. It was estimated that the statues of food for Buddha are similar to the Arhat statues, and most of the statues are well-formed. The rock used to carve the Buddha statues is banded gneiss with distinct foliation, alternating between white bands of quartz and feldspar and black bands composed of biotite. The Buddha statues have been damaged by physical weathering, discoloration, and biological contamination. In damage evaluations, joint (3.6 crack index), peeling (5.2%), exfoliation (1.7%), and falling off (0.1%) were observed on the rock surface of the Buddha statues. In particular, due to severe biological weathering, stage 9 and 10 biological coverage of the rock surface accounted for 57.5% of the total area, and stages 5 to 8 also accounted for a high share at 22.3%. The discoloration factors were shown to be dark brown and white with Fe, Ca, and S, and a large amount of C detected in the blackened contaminants, and the damage weight high in all areas. Discontinuities in different directions were identified in the rock surface. Analysis of potential rock failure types indicated that there is a possibility of plane and toppling failure, but wedge failure is unlikely to occur. The mean ultrasonic velocity of the main rock surface was 2,463m/sec, the lower part of the left side with a large number of joints was relatively low, and the highly weathered (HW) type to the completely weathered (CW) type concentrated distribution, showing weak properties. For the Buddha statues, conservation treatment is required for about 14.9% of micro cracks and 58.9% of exfoliation cracks. In addition, in order to improve the conservation environment of the Buddha statues, maintenance of drainage and ground preparations for the rock surface gradient and plants are necessary, and protection facilities should be reviewed for long-term conservation and management purposes.

• Journal of Life Science
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• v.27 no.9
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• pp.975-985
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• 2017

To investigate the beneficial effects of an agar gel mask (AGM) on UV-induced photoaging, SKH-1 hairless mice were treated with a topical application of AGM and an AGM dipped in essence (AGMdE). The mice were divided into an no radiation group, UV + AGM, UV + AGMdE, and UV + vehicle (PBS) treatment groups. Alterations in skin wrinkles, skin phenotype, histological structures, oxidative status, and toxicity were then evaluated during 4 weeks of exposure. The topical application of AGM and AGMdE inhibited wrinkle formation, suppressed the erythema index, prevented transepidermal water loss, and enhanced skin hydration. In addition, epidermal thickness recovered to a similar level as that in the no irradiation group in the UV + AGM and UV + AGMdE treatment groups compared with the UV + vehicle (distilled water) group. Furthermore, the expression levels of matrix metalloproteinase-1 (MMP-1) and tyrosinase were reduced in the UV + AGM and UV + AGMdE treatment groups, although the highest level varied. Moreover, superoxide dismutase (SOD) activity was significantly lower in the UV + AGM and UV + AGMdE treatment groups as compared with the UV + vehicle group. No significant alterations induced by most toxic compounds were measured in serum biochemical markers and liver and kidney histological features of the UV + AGM and UV + AGMdE treatment groups. These results suggest that AGM may protect against skin aging by regulating skin morphology, histopathological structures, and oxidative conditions.

• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.92-98
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• 2004

The adsorption and desorption of Pb, Cd, Co, Zn, Cr, Co, Ni, and Mo on the waste Undaria sp. were studied. Except for Pb. the mono adsorption rate for all heavy metals were lower than that of the heavy metals mixed. However, the adsorption capacity of the heavy metals by 1g of biosorption, in mixed heavy metals increased According to FT-IR analysis of the biosorbent after heavy metal biosorption, the replacement of the functional group by the heavy metals ions could be confirmed and the inverted peaks became larger after heavy metals adsorption. The adsorption equilibrium of heavy metals was reached in about 1 hour. The equilibrium parameters were determined based on Langmuir and Freundlich isotherms. The affinity of metals on the biosorbent decreased in the following order: Pb>Cu>Cr>Cd>Co. The desorption rate decreased in the following sequence: NTA>$H_2SO_4$>HCl>EDTA. The desorption rate of heavy metals by NTA increased with increase in the concentration from 0.1 to 0.3% but the desorption rate became constant beyond 0.3%. Therefore, it represented that desorption rate of heavy metals was suitable under optimized condition ($30^{\circ}C$, pH 2 and 0.3% NTA solution) and was fast with 80% or more the uptake occurring within 10 min of contact time.

• Journal of the Korean Arthroscopy Society
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• v.12 no.3
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• pp.172-179
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• 2008

Purpose: To evaluate the functional and structural results of arthroscopic double-row repair using combined knot-tying and knotless suture anchors in rotator cuff tears. Materials and Methods: From March 2006 to June 2007, twenty-one patients (15 males, 6 females; mean age 55.6 years; range 48 to 67) were included who underwent arthroscopic double-row repair for full-thickness tears of the rotator cuff following conservative treatment for a mean of 6.5 months (range 3 to 11). The tear size was carefully inspected arthroscopically and we found 2 small, 13 medium and 6 large-sized rotator cuff tears, with a mean tear size of 2.5cm(range 1.8 to 3.2). The repair constructs were consisted of horizontal mattress sutures using conventional knot-tying suture anchors medially and simple suture at the same level of medial row stitch with Bioknotless RC anchors (DePuy Mitek, Norwood, MA) as lateral row. Clinical and functional evaluations were made according to the range of motion, the ASES, UCLA scale and the isokinetic strength testing. Postoperative cuff integrity was determined through magnetic resonance imaging. The mean follow-up was 15 months (range 13 to 24). Results: The average clinical outcome scores and strength were all improved significantly at the time of the final follow-up (p < 0.01). Nineteen patients (90%) were satisfied with the result of the treatment. In 17 of 21 patients (81%) were judged to reveal healed tendon on magnetic resonance imaging at a mean of 7 months postoperatively. There were no significant functional differences according to the preoperative tear size (p<0.01), but large-sized tear shows less favorable structural results in 3 out of 6 cases(50%). Conclusion: Our results document the usefulness and variability of arthroscopic double-row rotator cuff repairs comparable to the results of the other types of double-row repairs.

• Journal of Environmental Impact Assessment
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• v.26 no.2
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• pp.160-170
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• 2017

The purpose of this study is to perform clustering of the habitat types and to identify the characteristics of species in the habitat types using mammal data (70,562) of the 3rd National Ecosystem Survey conducted from 2006 to 2012. The 15 habitat types recorded in the field-paper of the 3rd National ecosystem survey were reclassified, which was followed by the statistical analysis of mammal habitat types. In the habitat types cluster analysis, non-hierarchical cluster analysis (k-means cluster analysis), hierarchical cluster analysis, and non-metric multidimensional scaling method were applied to 14 habitat types recorded more than 30 times. A total of 7 Orders, 16 Families, and 39 Species of mammals were identified in the 3rd National Ecosystem Survey collected nationwide. When 11 clusters were classified by habitat types, the simple structure index was the highest (ssi = 0.07). As a result of the similarities and hierarchies between habitat types suggested by the hierarchical clustering analysis, the residential areas were the most different habitat types for mammals; the next following type was a cluster together with rivers and coasts. The results of the non-metric multidimensional scaling analysis demonstrated that both Mus musculus and Rattus norvegicus restrictively appeared in a residential area, which is the most discriminating habitat type. Lutra lutra restrictively appeared in coastal and river areas. In summary, according to our results, the mammalian habitat can be divided into the following four types: (1) the forest type (using forest as the main habitat and migration route); (2) the river type (using water as the main habitat); (3) the residence habitat (living near residential area); and (4) the lowland type (consuming grain or seeds as the main feeding resource).

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.152-159
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• 2002

The seasonal variations of nitrifying bacterial population sampled from 3 sites in Moon-Chon reservoir were analyzed by in situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes from August 2000 until July 2001. In addition, physico-chemical parameters such as temperature, pH, chi-a and DOC were measured to determine correlations between those factors and the size of nitrifying bacterial populations. Total bacterial numbers varied in the range of $0.8{\sim}1.5{\times}10^6\;cells/ml$ independent of sites and had the maximal values in March at all 3 stations. The ratio of eubacteria to total bacteria ranged from 44.9% to 79.5%, and the ratio of each nitrifying bacteria to eubacterial numbers reached only $1.0{\sim}7.4%$. The variations of ammonia-oxidizing bacteria ranged from $1.1{\times}10^4$ to $3.0{\times}10^4\;cells/ml$ without noticeable peak values whereas those of nitrite-oxidizing bacteria varied in $1.3{\sim}5.7{\times}10^4\;cells/ml$ with the increasing tendency in winter regardless of the sites. Moreover it was observed that the numbers of nitrite-oxidizing bacteria were higher than those of ammonia-oxidizing bacteria. Total bacterial numbers correlated with water temperature (r = 0.355, p<0.05) and DOC (r = 0.58G, p<0.01) positively whereas nitrite-oxidizing bacteria correlated with temperature (r = -0.416, p<0.05) and pH (r = -0.568, p = 0.001) negatively. In addition, DOC represented good correlations with eubacterial numbers (r = 0.448, p<0.01). These results indicate that temperature, DOC and pH might be one of the main factors affecting variations of bacterial populations in the aquatic ecosystem. It was also suggested that FISH method is a useful tool for detection of slow growing nitrifying bacteria.

• The Journal of the Petrological Society of Korea
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• v.19 no.3
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• pp.167-180
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• 2010

The geochemical studies on the plutonic rocks of the Geochang, the central part of the Ryongnam massif, were carried out in order to constrain the petrogenesis and the paleotectonic environment. The objects of this study are dioritic rocks, biotite granite and hornblende granite. The modal compositions indicate that the dioritic rocks are quartz diorite, quartz monzodiorite, tonalite, biotite granites are granodiorite, granite and hornblende granites are granite, quartz monzonite, quartz syenite. These rocks belong to the calc-alkaline series. Especially, trace elements such as Sr, Nb, Sr, Ti are depleted, suggesting that these rocks are produced in the subduction zone related to calc-alkaline series. Also, the studied granitic rocks correspond to peraluminous and I-type. Chondrite-normalized REE patterns show that LREE are enriched much more than HREE, and have weak Eu(-) anomaly. It is similar to pattern of Jurassic granitoids in the South Korea. Total REE value of the biotite granite and hornblende granite ranges 76.21~137.05 ppm and 73.84~483.21 ppm, respectively, also $(La/Lu)_{CN}$ value ranges 9.61~36.47 and 7.17~21.85. It is suggest that studied rocks suppor their emplacement at active continental margin. Also, these rocks are derived from magma generated by partial melting of lower continental crust materials.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.33-40
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• 2009

From 2006 to 2008, natural habitat of Sparassis crispa were surveyed for investigating ecological conditions at sixteen different sites in Korea. The investigated sites showed very wide altitudinal distribution ranged from 240 meters to 1,100 meters above the sea level. In general, S. crispa showed distinct feature of heart-rot fungi as it occurs on soils around the stems of larch (Larix kaempferi) and Korean white pine (Pinus koraiensis). But it also could be found on stems or on the stumps of dead trees, which indicated that the fungus might have several invasion routes and capabilities to grow on various ecological conditions. All of the sixteen sites were pure stands consisted with conifers such as larch or Korean white pine. The dominant tree layer showed $15.3{\sim}38.0$ meters for tree heights, thicker than twenty centimeters for the diameter at breast height (DBH), and all of them were older than thirty years. Since the stands were pure stand, species diversity of trees in the sites was extremely low. While the dominant tree layer showed only pure coniferous stand, the co-dominant tree layer, shrub layer and herbaceous layer showed more diverse features with higher Shannon-Wiener (H') indices. Soil texture of thirteen sites among sixteen investigated sites were loamy soils, and the contents of organic matter in soil were more or less higher than general forest soils in Korea with $3.79{\sim}14.32%$. The cation exchange capacity (CEC) was also relatively higher than general forest soils with $16.1{\sim}27.2$ cmol+/kg. The data indicated that the cauliflower mushroom occurring sites were relatively fertile than general forest soils. The soils were acidic with pH ranged from 4.2 to 5.2, which were typical features for conifer stands in Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.108-128
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• 2002

In order to investigate the ecological characteristics of phytoplankton communities around a nuclear power plant in Gori coastal waters of the South East Sea, Wolseong and Uljin coastal waters of the East Sea and Younggwang coastal waters of the Yellow Sea, the standing crops and chlorophyll-$\alpha$ concentrations of phytoplankton were studied during 1992~1996 and the relationships between standing crops and environmental variables were analyzed. The concentrations of nitrogenous nutrients were on average 0.101, 0.094, 0.072 and 0.108mg/$\ell$ and those of phosphorus were on average 0.007, 0.008, 0.006 and 0.009mg/$\ell$ in Gori, Wolseong, Uljin and Younggwang, respectively. The N:P ratios were highly variable, ranging from 3.2 to 57.3, from 3.1 to 109.0, from 2.6 to 102.0 and from 1.0 to 165.0 in Gori, Wolseong, Uljin and Younggwang, respectively. The concentrations of suspended solids were on average 18.7, 16.7, 11.6 and 52.7mg/$\ell$ and transparencies were on average 3.8, 5.4, 7.9 and 0.7 m in Gori, Wolseong, Uljin and Younggwang, respectively. Total standing crops of phytoplankton averaged 710,659, 687,508, 656,245 and 1,278,173cells/$\ell$ in Gori, Wolseong, Uljin and Yaunggwang, respectively. The standing crops of microplankton(>20${\mu}{\textrm}{m}$) averaged 357,546, 333,638, 276,407 and 592,975cells/$\ell$ those of nanoplankton(<20${\mu}{\textrm}{m}$) averaged 353,113, 353,870, 379,838 and 574,563cells/$\ell$ in Gori, Wolseong, Uljin and Younggwang, respectively. While standing crops of diatoms were averaged 282,009, 284,710, 238,758 and 574,563 cells/$\ell$, those of dinoflagellates were averaged 46,079, 35,401, 32,906 and 16,749 cells/$\ell$ in Gori, Wolseong, Uljin and Younggwang, respectively. The seasonal standing crops of diatoms in Gori, Wolseong and Uljin were higher in Spring than other seasons, but were lower in Summer than other seasons in Younggwang. The seasonal standing crops of dinoflagellates in Gori and Younggwang were higher in Summer than other seasons, but were higher in Autumn than other seasons in U]jin. Average of chlorophyll-$\alpha$ concentrations ranged from 2.16 to 4.28$\mu\textrm{g}$/$\ell$ in 4 study areas with the highest concentration occurred in Younggwang. Indices of species diversity ranged from 2.11 to 2.24 in 4 study areas. While community structures of phytoplankton were unstable during winter and stable during summer in Gori, Wolseong and Uljln coastal waters, those of phytoplankton were stable during winter and summer than during spring and autumn in Yaunggwang. The analysis results of Pearson product moment correlation coefficient between standing crops and environmental variables showed that distributions of standing crops were affected by transparencies, suspended solids, and some nutrient(N $O_3$$^{[-10]}$ -N, P $O_4$$^{3-}$-P), even though the degree of influences were a little different according to the season and the surveyed zone.