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Earthworm Composition and Seasonal Population Structure in Different Korean Golf Courses (우리나라 골프장의 지렁이 종 다양성 및 계절별 군집 구조)

  • Shin, Chong Chang;Hong, Yong;Lee, Dong Woon
    • Weed & Turfgrass Science
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    • v.5 no.3
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    • pp.155-164
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    • 2016
  • Earworm is very useful animal in soil ecosystem, however it is harmful for golf courses because they introduce many cast on turfgrass that reduces turf uniformity and play quality. However, no information has found on earthworm diversity and seasonal fluctuation in different Korean golf courses. In this study, we focused to carry out earthworm species composition and seasonal population structure in turfgrass of golf courses. During spring and fall season survey with direct digging and tea saponin drenching sampling in 5 different golf courses, 6 species under 3 families of earthworms were collected. Earthworm species composition and density was different among the golf courses. Aporrectodea caliginosa in Lumbricidae was dominant species in Anseong and Dongrae Benest Golf Club; however Amynthas carnosus in Megascolecidae was dominant species in Anyang and Glenrose Golf Club. Ap. caliginosa was collected only aclitellum in July and Am. carnosus was collected aclitellum and clitellum in August in golf courses. Seasonal population of earthworm was different depending on earthworm species (Am. hupeiensis was the highest in August and Ap. caliginosa was in April) however small number of collected earthworm species were not dominant trend in golf courses.

Effects of Food Quality and Temperature on life History Traits of Moina macrocopa Reared in Laboratory

  • Yoon, Seong Myeong;Lee, Jung Sup;Jung, Suk Hun;Baek, Kyoung Hwan;Chang, Cheon Young;Lee, Sung Kyu;Kim, Won
    • Animal cells and systems
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    • v.4 no.4
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    • pp.329-336
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    • 2000
  • Life table experiments were performed in order to examine the effects of food quality on Moina macrocopa fed with four kinds of algal foods, Botryococcus sp., Scenedesmus subspicatus, Selenastrum capricornutum, and Chlorella sp., at $20^{\circ}C$ . The temperature effects on M. macrocopa were also assessed, feeding Chlorella at $17^{\circ}C$,$20^{\circ}C$,$25^{\circ}C$, and a combination of $28^{\circ}C$ (light) and $25^{\circ}C$ (dark). The cartilaginous Botryococcs cells were Inappropriate food for Moina. Among the foods tested, Chlorella was the food of the best quality in all accounts of life history traits. Moina grown on Chlorella showed higher net reproductive rate ($R_0$), longer mean and maximum longevities, earlier mean age at maturity, longer mean carapace length at maturity, larger mean clutch size, and shorter mean time interval between clutch productions than those grown on Selenastrum and Scenedesmus. An optimal temperature for Moina was $20^{\circ}C$ . When Moina were grown on Chlorella at $20^{\circ}C$, they showed the highest r, the highest $R_0$, the shortest T, the longest mean longevity, the earliest mean age at maturity, the longest mean carapace length at maturity, and the largest mean clutch size. The results of life table experiments showed that the individual and population growth patterns were much more affected by low temperature $17^{\circ}C$, than by high temperature ($\geq 20^{\circ}C$). In the optimal condition, the r value was very high, 5.1 in $d^{-1}$. In conclusion, the food quality and the temperature are the most important factors to govern the size and continuity of Moina population, by which the individual growth rates and reproductivity of members in the population can be controlled to survive in their environment such as small and temporary water bodies in nature.

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Estimation of Duck House Litter Evaporation Rate Using Machine Learning (기계학습을 활용한 오리사 바닥재 수분 발생량 분석)

  • Kim, Dain;Lee, In-bok;Yeo, Uk-hyeon;Lee, Sang-yeon;Park, Sejun;Decano, Cristina;Kim, Jun-gyu;Choi, Young-bae;Cho, Jeong-hwa;Jeong, Hyo-hyeog;Kang, Solmoe
    • Journal of The Korean Society of Agricultural Engineers
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    • v.63 no.6
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    • pp.77-88
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    • 2021
  • Duck industry had a rapid growth in recent years. Nevertheless, researches to improve duck house environment are still not sufficient enough. Moisture generation of duck house litter is an important factor because it may cause severe illness and low productivity. However, the measuring process is difficult because it could be disturbed with animal excrements and other factors. Therefore, it has to be calculated according to the environmental data around the duck house litter. To cut through all these procedures, we built several machine learning regression model forecasting moisture generation of litter by measured environment data (air temperature, relative humidity, wind velocity and water contents). 5 models (Multi Linear Regression, k-Nearest Neighbors, Support Vector Regression, Random Forest and Deep Neural Network). have been selected for regression. By using R-Square, RMSE and MAE as evaluation metrics, the best accurate model was estimated according to the variables for each machine learning model. In addition, to address the small amount of data acquired through lab experiments, bootstrapping method, a technique utilized in statistics, was used. As a result, the most accurate model selected was Random Forest, with parameters of n-estimator 200 by bootstrapping the original data nine times.

Analysis of Factors Affecting Hand Hygiene Practices in Seafarers (선원들의 손위생 수행에 영향을 미치는 요인 분석)

  • Hwang, Jeong-Hee;Park, Eun-Kee;Yu, Byeng-Chul;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.34 no.1
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    • pp.73-86
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    • 2019
  • Seafaring is an important occupation that requires stringent hand hygiene practices as a basic method for preventing food-borne illness and infectious diseases when the diseases occur on board. The purpose of this study is to provide fundamental data for the prevention of food-borne illness and infectious disease on the ship by investigating the level of hand hygiene practices and influencing factors. A total of 222 seafarers were surveyed at a seafarers' educational institution between July and August 2017. Their hand hygiene practice were examined by a modified method using the guidelines which are recommended by the World Health Organization, the Centers for Disease Control and Prevention, and Hand Hygiene Australia. The mean of hand hygiene practice was 47.97 out of 75 points. By category, the most frequent hand hygiene practice was measured as 4.04 on a 5-point scale as 'after working'. Factors affecting hand hygiene practices were ship tonnage relating to in job characteristics, exercise in health-related characteristics, and soap in relation to the characteristics of the hand hygiene environment on board. To improve hand hygiene among seafarers, it is necessary to raise awareness of hand hygiene among seafarers who work on small ships in particular, and to improve the systems of hand hygiene on ships with continuous education, hygiene practice evaluation and feedback.

Diffusion Tensor-Derived Properties of Benign Oligemia, True "at Risk" Penumbra, and Infarct Core during the First Three Hours of Stroke Onset: A Rat Model

  • Chiu, Fang-Ying;Kuo, Duen-Pang;Chen, Yung-Chieh;Kao, Yu-Chieh;Chung, Hsiao-Wen;Chen, Cheng-Yu
    • Korean Journal of Radiology
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    • v.19 no.6
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    • pp.1161-1171
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    • 2018
  • Objective: The aim of this study was to investigate diffusion tensor (DT) imaging-derived properties of benign oligemia, true "at risk" penumbra (TP), and the infarct core (IC) during the first 3 hours of stroke onset. Materials and Methods: The study was approved by the local animal care and use committee. DT imaging data were obtained from 14 rats after permanent middle cerebral artery occlusion (pMCAO) using a 7T magnetic resonance scanner (Bruker) in room air. Relative cerebral blood flow and apparent diffusion coefficient (ADC) maps were generated to define oligemia, TP, IC, and normal tissue (NT) every 30 minutes up to 3 hours. Relative fractional anisotropy (rFA), pure anisotropy (rq), diffusion magnitude (rL), ADC (rADC), axial diffusivity (rAD), and radial diffusivity (rRD) values were derived by comparison with the contralateral normal brain. Results: The mean volume of oligemia was $24.7{\pm}14.1mm^3$, that of TP was $81.3{\pm}62.6mm^3$, and that of IC was $123.0{\pm}85.2mm^3$ at 30 minutes after pMCAO. rFA showed an initial paradoxical 10% increase in IC and TP, and declined afterward. The rq, rL, rADC, rAD, and rRD showed an initial discrepant decrease in IC (from -24% to -36%) as compared with TP (from -7% to -13%). Significant differences (p < 0.05) in metrics, except rFA, were found between tissue subtypes in the first 2.5 hours. The rq demonstrated the best overall performance in discriminating TP from IC (accuracy = 92.6%, area under curve = 0.93) and the optimal cutoff value was -33.90%. The metric values for oligemia and NT remained similar at all time points. Conclusion: Benign oligemia is small and remains microstructurally normal under pMCAO. TP and IC show a distinct evolution of DT-derived properties within the first 3 hours of stroke onset, and are thus potentially useful in predicting the fate of ischemic brain.

A Study of Stone Sculptures of Jagneung and Sareung - The Reinstatement and Stone Sculpture Simplification - (장릉(莊陵)과 사릉(思陵)의 석물 연구 - 추봉과 석물 간소화를 중심으로 -)

  • Kim, Yi Soon
    • Korean Journal of Heritage: History & Science
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    • v.45 no.1
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    • pp.34-51
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    • 2012
  • Jangneung (the Royal Tomb of King Danjong) and Sareung (the Royal Tomb of Queen Jeongsun) are simple in their design and layout. Not only are the sizes of the stone statues small, but stone soldiers are not installed at all despite the fact that Danjong at one point served as the King of Joseon. Moreover, only a pair of seoksu (stone animal) is installed for each Tomb. These royal tombs were originally made as common tombs and later upgraded as Royal Tombs when Danjong's royal status was reinstated posthumously in 1698. Thus, in comparison to royal tombs in general, the scale of these tombs is by far modest. For this paper, archival records and other literature for the burial upgrade process and the stone sculptures are examined; also, the stone sculptures have been examined and measured on-site, and they have been compared and analyzed based on the data thus obtained. Furthermore, this paper traces the historical context of the period in which the simplification of the stone sculptures took place for Jangneung and Sareung. The paper argues that the cause of the modest scale lies not so much in the fact that King Danjong had been dethroned as a commoner, but in the cataclysmic famine and epidemic that swept the country during the time when the two royal tombs were upgraded as such.

Are critical size bone notch defects possible in the rabbit mandible?

  • Carlisle, Patricia L.;Guda, Teja;Silliman, David T.;Hale, Robert G.;Baer, Pamela R. Brown
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.45 no.2
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    • pp.97-107
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    • 2019
  • Objectives: Small animal maxillofacial models, such as non-segmental critical size defects (CSDs) in the rabbit mandible, need to be standardized for use as preclinical models of bone regeneration to mimic clinical conditions such as maxillofacial trauma. The objective of this study is the establishment of a mechanically competent CSD model in the rabbit mandible to allow standardized evaluation of bone regeneration therapies. Materials and Methods: Three sizes of bony defect were generated in the mandibular body of rabbit hemi-mandibles: $12mm{\times}5mm$, $12mm{\times}8mm$, and $15mm{\times}10mm$. The hemi-mandibles were tested to failure in 3-point flexure. The $12mm{\times}5mm$ defect was then chosen for the defect size created in the mandibles of 26 rabbits with or without cautery of the defect margins and bone regeneration was assessed after 6 and 12 weeks. Regenerated bone density and volume were evaluated using radiography, micro-computed tomography, and histology. Results: Flexural strength of the $12mm{\times}5mm$ defect was similar to its contralateral; whereas the $12mm{\times}8mm$ and $15mm{\times}10mm$ groups carried significantly less load than their respective contralaterals (P<0.05). This demonstrated that the $12mm{\times}5mm$ defect did not significantly compromise mandibular mechanical integrity. Significantly less (P<0.05) bone was regenerated at 6 weeks in cauterized defect margins compared to controls without cautery. After 12 weeks, the bone volume of the group with cautery increased to that of the control without cautery after 6 weeks. Conclusion: An empty defect size of $12mm{\times}5mm$ in the rabbit mandibular model maintains sufficient mechanical stability to not require additional stabilization. However, this defect size allows for bone regeneration across the defect. Cautery of the defect only delays regeneration by 6 weeks suggesting that the performance of bone graft materials in mandibular defects of this size should be considered with caution.

Maximum tolerated dose estimations using various stopping rules in phase I clinical trial (제 1상 임상시험에서 다양한 멈춤 규칙을 이용한 최대허용용량 추정법)

  • Jeon, Soyoung;Kim, Dongjae
    • The Korean Journal of Applied Statistics
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    • v.35 no.2
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    • pp.251-263
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    • 2022
  • Phase I clinical trial is called 'Dose finding study'. It is first step of experimenting on humans with new drugs developed through animal experiments or vitro experiments. The important area of interest in designing Phase I clinical trial is determining the dose that acceptable level to the patients and provides the greatest efficacy. In this paper, we explain about methods to determine the maximum tolerated dose using various stopping rules. The SM3, NM, Rim, J3, BSM methods are compared through simulation. And we consider how the methods might be reformed. As a result of the simulation, BSM estimated the MTD closest to the target toxicity probability. J3 method required the least number of subjects. These results are due to the feature of the stopping rules of both methods. The BSM adds 2 or 1 subject at the same dose level when there is a toxic reaction. In addition, the J3 method has a smaller number of subjects than the other methods. If the methods are improved by combining these features, MTD can be estimated more efficiently. If the total number of subjects can be reduced while using the stopping rule of the BSM, accurate estimation is possible for a small number of subjects.

Evaluation of the efficacy of modified Samultang in female menopausal animal models using ovarian resection rats (난소절제 랫드를 이용한 여성갱년기 동물모델에서 변형 사물탕의 효능평가)

  • Hwang, Seonghee;Park, Sunyoung;Shin, Yong Kook
    • Journal of the Korea Convergence Society
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    • v.13 no.4
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    • pp.573-582
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    • 2022
  • In order to develop samultang with reduced side effects, modified samultang using omija was oral administered to rats with ovarian resection, and changes in evaluation indicators of functional efficacy in women's menopause were measured. In weight gain, relative weight of uterus and vagina, blood lipid-related indicators, and changes in blood estradiol, there was no statistically significant improvement effect in modified Samultang compared to the control group. However, the expression of estrogen receptor alpha and beta in intrauterine tissue tended to increase, and the expression of phosphorylated ERK, which is known to be involved in estrogen receptor signaling, showed a significant increase in activation in ERK and AKT. The expression amount of phosphorylation AKT was not significant, but showed an increasing tendency. Even though the test substance was administered in a relatively small dose, it is judged that the test substance modified Samultang has the ability to activate estrogen receptor. In the future, it is expected that it can be used as a useful natural mixture to show the efficacy of samultang with fewer gastrointestinal disorders.

Pathophysiological Functions of Deubiquitinating Enzymes in Obesity and Related Metabolic Diseases (탈유비퀴틴화 효소 DUBs의 비만 및 대사 관련 질환에서 병태생리학적 기능)

  • Lee, Seul Gi;Kwon, Taeg Kyu
    • Journal of Life Science
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    • v.32 no.6
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    • pp.476-481
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    • 2022
  • Ubiquitin signaling regulates virtually all aspects of eukaryotic biology and dynamic processes in which protein substrates are modified by ubiquitin. To regulate these processes, deubiquitinating enzymes (DUBs) cleave ubiquitin or ubiquitin-like proteins from these substrates. DUBs have been implicated in the pathogenesis of cancer, leading to the development of increasing numbers of small-molecule DUB inhibitors. On the other hand, recent studies have focused on the function of DUBs in metabolic diseases such as obesity, diabetes, and fatty liver diseases. DUBs play a positive or negative role in the progression and development of metabolic diseases. Their involvement in cell pathology and regulation of major transcription factors in metabolic syndrome has been examined in vitro and in animal and human biopsies. UCH, USP7, and USP19 were linked to adipocyte differentiation, body weight gain, and insulin resistance in genetic or diet-induced obesity. CYLD, USP4, and USP18 were found to be closely associated with fatty liver diseases. In addition, these liver diseases were accompanied by body weight change in certain cases. Collectively, in this review, we discuss the current understanding of DUBs in metabolic diseases with a particular focus on obesity. We also provide basic knowledge and regulatory mechanisms of DUBs and suggest these enzymes as therapeutic targets for metabolic diseases.