• The Korean Journal of Malacology
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• v.29 no.4
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• pp.273-281
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• 2013

In order to evaluate how the effects of aquacultural environment, such as temperature, salinity, DO, SS, Chlorophyll-a, COD and nutritive salts on Cupped oysters, an investigational study was conducted between September to December of 2011. During the study, different intermediate cage farms on the surface of the sea were used to culture and compare the growth and survival rate of the Cupped oysters in different fishing environments. The different intermediate cage farms used were Wonsando-ri, Chang-ri, and Pado-ri. In January of 2012, these oysters were transplanted to a horizontal net farm in a mudflat until July of that year. The adaptation rates of the Cupped oysters were tested at differential exposure times at varying intertidal periods. Wonsando-ri showed the highest water temperature and Chlorophyll-a levels, while the salinity was found to be within range of stable conditions among all three intermediate cage farms. Once the Cupped oysters were at the horizontal net farm, the growth was measured at distinct tidal exposure time of 1, 3, and 5 hours, whereby the growth rate was highest at 3, 1, and 5 hours, respectively. In addition, the oysters cultivated in intermediate cage farms had longer shell lengths compared to shell heights, while oysters cultured in the horizontal net farm had larger shell heights than shell lengths.

• Korean Journal of Environment and Ecology
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• v.31 no.4
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• pp.397-408
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• 2017

The purpose of this study is to identify the home range and habitat using pattern of the native species, Mauremys reevesii, and the exotic species, Trachemys scripta elegans, and to analyze the mutual competition relationship of the two species. This study was conducted at the Goldfish square pond, which is located in the upper part of the valley of Cheonggye mountain from August 2, 2010 to January 30, 2011. We used the three artificially proliferating M. reevesii and three T. scripta elegans which were inhabited in the ponds and reservoirs for monitoring study after attaching the transmitter to each of them. We measured the home range and the habitat utilization radius of three individuals of each species and the environmental factors such as temperature, humidity and soil and water temperature around the Goldfish square pond. As our results, it was analyzed that the M. reevesii and T. scripta elegans have a redundant ecological positions in various aspects such as limited sunbathing places, food resource utilization, hibernation place, etc. We also found that the relatively small M. reevesii was being pushed out of the competition by the relatively big. Further investigation of food competition and habitat utilization should be necessary for these two species for the natural habitats, their home range, food competition, and habitat utilization. The result of this study will be the basic data M. reevesii's restoration project.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.78-85
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• 2015

Population ecology of Rhodeus uyekii (Pisces: Acheilognathinae) was investigated at the Bongseocheon, Mankyeonggang (River) in Korea, from January to December 2014. It mainly inhabits the slow-flowing waters having mud bottoms. Measurement of the standard length of the population indicated that the following standardization: 24~29 mm are one year old, 30~35 mm are two years old, 36~39 mm are three years old, and >40 mm group are regarded over four years old (October in 2014). The spawning season was from March to June, with water temperatures in the range $11.5{\sim}27.0^{\circ}C$. The sex ratio of female : male was 1 : 0.77. The number of eggs in the ovaries was 104~168 ($mean{\pm}SD$: $124{\pm}18.1$). The size of the matured eggs was 2.8~3.5 ($3.2{\pm}0.15$) mm in the long axis, and 1.4~1.5 ($1.4{\pm}0.03$) mm in the short axis. The eggs were found in Unio douglasiae and the number of eggs, larvae or both was 3~18 ($10.2{\pm}5.0$). Stomach contents were mainly phytoplanktons such as the genera Navicular, Cocconeis, Cymbella (Bacilariophyceae) and Cloniophora (Chlorophyceae).

• Korean Journal of Plant Taxonomy
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• v.50 no.2
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• pp.89-119
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• 2020

Species invasions have rapidly increased due to the substantial growth of global trade in the recent past. As the awareness of the negative effects on natural ecosystems derived from alien species has grown, many countries and lawmakers have enacted rules and policies on the conservation of indigenous plants. Unfortunately, in Korea, research on species invasion is seriously lacking despite the growing number of alien species. In the current study, we report alien plants that have intentionally and/or unintentionally been introduced in Korea and also presented a checklist of invasive plants found both in the literature and in field surveys. We reviewed all documented records of alien plants, i.e., scientific papers, illustrated books, and annual reports. We also categorized alien plants by origin, time of introduction, naturalization, and the rate of their spread. The results revealed that there are 619 alien plant taxa (96 families, 353 genera, 595 species, 6 subspecies, 11 varieties, 1 forma, and 6 hybrids) occurring in Korea. Among these, 30 taxa are archaeophytes (Arc.), 214 are potentially invasive plants (PIPs), and 375 are invasive alien plants (IAPs). In addition, IAP taxa consist of grades 5 (widespread, WS) to 1 (potential spread, PS) of alien plants according to the rate of spread in Korea. Our results suggested that the number of alien plants is likely to keep growing; thus, the distribution should be regularly monitored and the list of alien plants must be updated.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.69-78
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• 2017

Cordyceps militaris has been used in traditional Chinese medicine owing to its anticancer and immunomodulatory activities. Germanium compounds have also been shown to be associated with many pharmacological functions, such as antimicrobial, antiviral, antitumor, antimutagenic, and immunomodulating effects. In this study, we examined the biological properties of hot water extract from mycelial liquid culture of germanium-enriched C. militaris (CMGe). CMGe displayed a concentration-dependent antiproliferation activity against four human cancer cell lines. The antiproliferative activity of CMGe was 2-4-fold lower than that of hot water extract from mycelial liquid culture in C. militaris (CM). However, CM had a concentration-dependent cytotoxicity to human bone marrow-derived mesenchymal stem cells (MSCs). Contrastingly, CMGe did not cause any cellular damage to MSCs. MSCs cultured with CMGe displayed an increased proliferative activity with no cytotoxic effect. The oral administration of CMGe inhibited increased tumor volume and weight compared with the control group. CMGe has the potential to be used as an industrial product in medicinal foods as well as in pharmaceutical products.

• Membrane Journal
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• v.27 no.3
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• pp.248-254
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• 2017

In order to secure the reliability of pathogenic microorganisms such as Cryptosporidium and Giaridia, which are chlorophilic protozoans, membrane filtration systems have been widely used in water purification process. hese integrity tests are classified into direct and indirect methods. Based on the bubble point theory, the pressure-based test in the direct method is presented in the USEPA Guidance Manual with sensitivity to detect a minimum size of pathogenic microorganisms of $3{\mu}m$ or more. Indirect methods are widely used in that they are capable of continuous operation in on-line state, but there is a very low sensitivity of damage detection compared to the direct method, and there is a limit that can not specify the damage area, so it is necessary to improve this sensitivity. In this study, we compared the LRVDIT and UCL values according to the type of membrane defect, number of fiber breaks, and initial set pressure value through the Integrity Test by Pressure Decay Test (PDT).

• Journal of Wetlands Research
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• v.17 no.1
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• pp.91-100
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• 2015

The aim of this study is to compare and analyze plant monitoring results of 2012 and 2013 for three artificial wetlands of Binae, Sedo, and Okpo areas in Namhan river, Keum river, and Nakdong river respectively. As the results, the Binae wetland in 2013 shows the same environment with 2012, that is, Willow and Common reed were dominant and the distributed plants in the wetland were Phragmites japonica Steud, Carex dispalta Boott, and Humulus japonicus in lowland of river side. Especially, Humulus japonicus was increased in summer season and Willow was increased in lowland of 초원. In Okpo wetland, Water chestnut was appeared in 2013 which it was not in 2012. Reed distribution was reduced in 2013 comparing to 2012 but Pussy willow distribution was not changed in 2013. In Sedo wetland, Secondary grassland was artificially planted in 2013 and so the colony was changed to Chinese Lespedeza and also most of plant colony was changed to Colt's-tail. Therefore, we can know that wetted transition rather than dried transition will be occurred in the Binae wetland. However, the Okpo wetland has monotonic change and so the transition will be proceeded with long time. The Sedo wetland showed wetted and dried transitions exist together. Therefore, the wetland will be changed to Reeds, Common reed, and Willow colonies.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.219-239
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• 2017

This study was carried out to investigate the vascular plants of the protected area for forest genetic resource conservation in the National Yonghyeon natural recreation forest. The vascular plants collected 7 times (from February to September 2014) were consist of total 460 taxa; 95 families, 280 genera, 398 species, 3 subspecies, 50 varieties and 9 forms respectively. The 6 taxa of Korean endemic plants and 8 taxa of Korean rare plants were investigated. The floristic regional indicator plants found in this area were 43 taxa comprising 7 taxa of grade IV, 7 taxa of grade III, 12 taxa of grade II, 17 taxa of grade I. The naturalized plants were 39 taxa, therefore naturalized ratio was 8.5%. 460 taxa listed consist of 189 taxa (41.1%) of edible plants, 155 taxa (33.7%)of medicinal plants, 177 taxa (38.5%) of pasture plants, 52 taxa (11.3%) of ornamental plants, 17 taxa (3.7%)of timber plants, 12 taxa (2.6%) of fiber plants and 3 taxa (0.7%) of industrial plants. The vegetation status of investigated area was comparatively well conserved, but human-induced damage is increasingly greater. Therefore, a long-term monitoring of vascular plants and vegetation movement must become accomplished.

• Journal of the Korea Concrete Institute
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• v.27 no.5
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• pp.511-519
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• 2015

Methods such table flow, slump and outflow time have used to be as a main evaluation criteria regards to fluidity of concrete. Since those methods mentioned above have some inaccuracies which are up to its condition of test. Studies that evaluate fluidity applying the rheology has increased its portion in this field. Meanwhile, demands for AAS binder have been increased in accordance with its demand for this market, studies for rheology of AAS binder are little though. Therefore, this paper mainly deals a rheological peculiarity of AAS binder according to its condition of W/B ratio and alkali activators. The fluidity of AAS paste was evaluated with the index of table flow and outflow time. And shear stress following its shear rate was analyzed through rheological test. Rheological parameters were deduced through this rheological test of Bingham model and analyzed its interrelation with fluidity test. As the final outcome, it proposed the interrelation among table flow, yield stress, viscosity and outflow time. In basis of this study, we would like to suggest a reference for mixing AAS mortars and concretes.

• Journal of the Korean Dietetic Association
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• v.14 no.1
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• pp.51-63
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• 2008

The purpose of this study was to understand the management status of food wastes in school meal to find the effective ways that would reduce and recycle them. Data was collected using questionnaires from 223 school dietitians located in Jeonbuk area. The results were as followed : 1) Waste was managed by the dietitians(54.7%) and cook(42.2%). The waste disposal contract was made by dietitians(65.0%), executives(31.4%). Therefore, school dietitians had primary responsibilities in the waste management. 2) As disposal ways, 48.9% processed municipal solid waste and food waste together and 46.6% processed separately. 3) A half of schools(52.9%) produced food wastes weighed under 10$\sim$15kg daily and using food wastes as animal food for farms was most popular method to dispose(87.4%). 4) Reasons to have food-wastes were disliking the taste of menu(50.2%) and the inappropriate ways of dealing with remaining food(64.1%) and donating to food bank(33.6%) in order. 5) The suggested ways to reduce the food-waste was to improve on cooking method(72.2%), changing of portion size(61.0%), measuring the amount of leftover food(53.4%) and requesting cooperation to educators(52.9%). 6) The reported consequences of reducing the food waste were: lowered grocery expenses(46.2%), and inspiring students on helping environmental preservation(23.8%). Therefore, the administration should work on finding a method to reduce food-waste and a way to use these resources efficiently. It is important to induct student's attitude on recycling remaining products by using food bank via nutrition education. Dietitian also should consider to reduce the leftover of food by using a standardized recipe.