• Title/Summary/Keyword: Within-group differences

Search Result 1,122, Processing Time 0.03 seconds

The Leaf Morphological Variation of Ten Regions of Natural Populations of Machilus thunbergii in Korea (후박나무 10개 천연집단의 엽형질 변이)

  • Yang, Byeong-Hoon;Song, Jeong-Ho;Lee, Jae-Cheon;Park, Young-Goo
    • Journal of agriculture & life science
    • /
    • v.45 no.3
    • /
    • pp.25-33
    • /
    • 2011
  • This study was conducted to examine genetic variation on leaf characteristics of Machilus thunbergii populations. Ten populations were subjected to multivariate analysis for 9 characteristics of leaf morphology. Average length of leaf blade, leaf width, petiole length, vein number were 9.8cm, 4.0cm, 1.8cm, 8.4 respectively, while angle of leaf base and leaf apex were $67.9^{\circ}$ and $78^{\circ}$ respectively. The coefficient of variation (C.V.) on leaf characteristics was 20% which indicate similar features among the populations. Nested analysis showed statistically signigicant differences among populations as well as among individuals within populations. Genetic relationship between populations using complete linkage method showed four groups to Euclidean distance 1.2 and did not show a tendency to cluster into the same group. There were three principal components that had a meaningful eigenvalue over 1.0 among the 9 components. The explanatory power of the top three main components on the total variation was 92.8%. The first principal component (PC) was explained about 40.3% which is mainly correlated with maximum leaf width and the second PC was explained about 28.7% which is correlated with leaf blade length. The third PC was explained about 23.8% which is correlated with petiole length ($X_3$). These characters were important factors for analysis of the relationship among natural populations of M. thunbergii.

A comparative study on child rights through the application of a child rights index ('아동권리지수' 적용을 통한 아동권리 비교 연구)

  • Lee, Bong Joo;Shin, Won Young
    • Journal of the Korean Society of Child Welfare
    • /
    • no.58
    • /
    • pp.171-203
    • /
    • 2017
  • There has been a growing number of research about children's development indicators and child well-being indicators. After the Convention on the Rights of the Child (CRC) and concluding observations on the second report of Korea, the effort to monitor and measure children's rights and the use of child rights indicators has increased within policy and academic research. However, few indicators provide a realization of children's rights. The purpose of this paper was to analyze children's own perceptions of their rights and to develop a children's rights index to measure children's rights. In this study, a children's rights index was developed from 38 indicators categorized into nine components and four domains (survival rights, development rights, protection rights, and participation rights) to measure children's rights. Data were gathered from 17,000 elementary and middle school children and their parents in 16 cities. The survey revealed significant differences in the children's rights index by region and age group. There was also a correlation between the economic circumstances of both households and communities and the children's rights index. In the light of the findings, it is suggested that there is a need to increase public investment on children and to raise awareness of children's rights in order to improve children's rights and to decrease disparity.

A Study on the Time-sharing Condominium use Behavior by Demographic Characterristics (인구통계변인에 따른 휴양콘도미니엄 이용행태 연구)

  • Kim, Jong Won;Ban, Seung Ju;Kim, Jae Tae
    • Korea Real Estate Review
    • /
    • v.24 no.1
    • /
    • pp.91-104
    • /
    • 2014
  • This paper studied condo selection attributes that affected satisfaction, recommendation and revisitation, in particular, investigated gender and age differences. Research target is the group who revisited time-sharing condominium within one year. The paper seeks to understand factors that affect and contribute to customer satisfaction and intentions for reuse. This study model was analyzed by the basic statistical analysis, factor analysis, reliability analysis and multiple analysis, using SPSS 18.0 and AMOS 18.0. We found that 5 condo selection attributes that have significant affect on user satisfaction: facility, service, product, accessibility and expense. Furthermore it was evident that user satisfaction has a significant effect on condo recommendation and intentions of reuse. With regard to sex, for male users expense, accessibility and service had a significant effect on their satisfaction level, while for female users, product was most important. User satisfaction both have a significant effect on recommendation and intentions of reuse but for females this was more evident. Regarding the age, for 20~30 age band, service and product factor had a significant effect on user satisfaction in order, whereas, for the age band of over 40s, expense, product and facility factors were important. User satisfaction of both have a significant effect on recommendation and intentions of reuse. In the meantime user satisfaction of 20~30 age band had a bigger positive significant effect on recommendation and intentions of reuse than the age band over 40s.

Study on the Evaluation Criteria of Termite Dust for Rapid Control of Wooden Structures Damaged by Termites (흰개미 가해 목조건축물의 급속 방제를 위한 분말형 약제(Termite Dust) 평가 기준 연구)

  • Im, Ik Gyun;Chung, Yong Jae
    • Journal of Conservation Science
    • /
    • v.35 no.3
    • /
    • pp.227-235
    • /
    • 2019
  • In Korea, various methods are applied to prevent wooden structures from being damaged by termites. However, since there is no way to quickly bring toxic substances in contact with the termites inside the timber, it leads to the damage of wooden cultural property due to the prolonged period of controlling the termites. Accordingly, an indoor evaluation criteria study was conducted for the introduction of powder-type termiticides in Korea, which produced rapid control effects by drilling wood and directly contacting and transferring toxic substances inside the timber. First, contact toxicity and transfer ability of termite dusts were evaluated to establish the criteria for evaluation of effectiveness against Reticulitermes speratus. The contact toxicity confirmed 100% mortality of fipronil, deltamethrin and cyfluthrin termite dusts within 24 h of contact; however, differences occurred in the active ingredient transfer time to the sublethal. In addition, in the case of transfer ability evaluation, the rate of mortality gradually decreased under 1:9 and 1:25 ratio conditions; however, the difference in the reduction rate was identified depending on the type of termite dust. the results of the evaluation of compressive strength of the wood showed that the difference in the measured values between the control group and the conditions of perforation 1 to 3 times, which does not significantly affect the compressive strength of wood. In this study, the criteria of termite dust selection and evaluation method of dust-type termiticides were presented and the applicability of the method was identified.

Marine ecosystem risk assessment using a land-based marine closed mesocosm: Proposal of objective impact assessment tool (육상 기반 해양 폐쇄형 인공생태계를 활용한 해양생태계 위해성 평가: 객관적인 영향 평가 tool 제시)

  • Yoon, Sung-Jin
    • Korean Journal of Environmental Biology
    • /
    • v.39 no.1
    • /
    • pp.88-99
    • /
    • 2021
  • In this study, a land-based marine closed mesocosm (LMCM) experiment was performed to objectively assess the initial stability of an artificial ecosystem experiment against biological and non-biological factors when evaluating ecosystem risk assessment. Changes in the CV (coefficient of value) amplitude were used as data to analyze the stability of the experimental system. The CV of the experimental variables in the LMCM groups (200, 400, 600, and 1,000 L) was maintained within the range of 20-30% for the abiotic variables in this study. However, the difference in CV amplitude in biological factors such as chlorophyll-a, phytoplankton, and zooplankton was high in the 600 L and 1,000 L LMCM groups. This result was interpreted as occurring due to the lack of control over biological variables at the beginning of the experiment. In addition, according to the ANOVA results, significant differences were found in biological contents such as COD (chemical oxygen demand), chlorophyll-a, phosphate, and zooplankton in the CV values between the LMCM groups(p<0.05). In this study, the stabilization of biological variables was necessary to to control and maintain the rate of changes in initial biological variables except for controllable water quality and nutrients. However, given the complexity of the eco-physiological activities of large-scale LMCMs and organisms in the experimental group, it was difficult to do. In conclusion, artificial ecosystem experiments as a scientific tool can distinguish biological and non-biological factors and compare and analyze clear endpoints. Therefore, it is deemed necessary to establish research objectives, select content that can maintain stability, and introduce standardized analysis techniques that can objectively interpret the experimental results.

Usual intake of dietary isoflavone and its major food sources in Koreans: Korea National Health and Nutrition Examination Survey 2016-2018 data

  • Kim, Yoona;Kim, Dong Woo;Kim, Kijoon;Choe, Jeong-Sook;Lee, Hae-Jeung
    • Nutrition Research and Practice
    • /
    • v.16 no.sup1
    • /
    • pp.134-146
    • /
    • 2022
  • BACKGROUND/OBJECTIVES: Accumulating evidence has shown the beneficial effects of isoflavone on health. There is limited information on the usual isoflavone intake for Koreans. This study examined the usual intake of total isoflavone and its major food sources in Koreans according to age and gender. SUBJECTS/METHODS: The dietary intake data of 21,271 participants aged 1 yrs and older from the Korea National Health and Nutrition Examination Survey (KNHANES) VII 2016-2018 were analyzed. The average isoflavone intake was estimated based on the 24-h dietary recall data in KNHANES and the isoflavone database from the Korea Rural Development Administration (RDA) and literatures. The usual isoflavone intake was estimated by applying the ratio of within- and between-participant variance estimated from the 2009 KNHANES data to the 7th KNHANES (2016-2018) data. The variance of the isoflavone intake was calculated using MIXTRAN macro with intake data for two days in the 2009 KNHANES. Complex sample analysis with stratified variables and integrated weights was conducted. RESULTS: The mean total isoflavone intake in the Korean population aged 1 yrs and older (n = 21,271) was 139.27 mg/d, which was higher than the usual intake of 47.44mg/d. Legumes were a major contributing food group (91%), with arrowroot being a major individual contributor to the isoflavone intake (67.2%), followed by 21.3% of soybean, 5.4% of bean sprouts, and 2.1% of tofu. The usual isoflavone intake was highest in the participants aged 50 to 64 yrs old and increased with age until 50 to 64 yrs and then decreased with further increases in age. The usual isoflavone intake of participants aged 65 yrs and older was higher for men than for women, showing gender differences. CONCLUSIONS: The usual dietary intake of isoflavone varied according to age and gender in the Korean population. This study showed that the usual isoflavone intake was lower than the average isoflavone intake. The difference between percentiles of the usual isoflavone intake was similarly smaller than the average intake. An estimation of average intake can be hindered by the occasional consumption of foods high in isoflavones, suggesting that the usual intake estimation method can be more appropriate. Further research will be needed to establish isoflavone dietary guidelines regarding the effects of isoflavone intake on health outcomes.

Validation of a physical activity classification table in Korean adults and elderly using a doubly labeled water method (한국 성인과 노인을 대상으로 이중표식수법을 이용한 신체활동분류표 타당도 평가)

  • Hye-Ji Han ;Ha-Yeon Jun;Jonghoon Park;Kazuko Ishikawa-Takata;Eun-Kyung Kim
    • Journal of Nutrition and Health
    • /
    • v.56 no.4
    • /
    • pp.391-403
    • /
    • 2023
  • Purpose: This study evaluated the validity of a physical activity classification table (PACT) based on total energy expenditure (TEE) and physical activity level (PAL) measured using the doubly labeled water (DLW) method in Korean adults and the elderly. Methods: A total of 141 (male 70, female 71) adults and elderly were included. The reference standards TEEDLW, PALDLW were measured over a 14-day period using DLW. A 24-hour physical activity diary was kept for three days (two days during the week and one day on the weekend). PALPACT was calculated by classifying the activity type and intensity using the PACT. PALPACT was multiplied by resting energy expenditure measured by indirect calorimetry to estimate TEEPACT. Results: The mean age of the study participants was 50.5 ± 18.8 years, and the mean body mass index was 23.4 ± 3.3 kg/m2. A comparison of TEEDLW and TEEPACT by sex and age showed no significant differences. The bias, the difference between TEEDLW and TEEPACT, was male 17.3 kcal/day and female -4.5 kcal/day. The percentage of accurate predictions (values within ± 10% of the TEEDLW) of TEEPACT was 58.6% in males and 54.9% in females, with the highest prediction values in the age group 40-64 years (70.9%) in males and over 65 years (73.9%) in females. The spearman correlation coefficient (r) between TEEPACT and TEEDLW was 0.769, indicating a significant positive correlation (p < 0.001). Conclusion: In this study, the use of a new PACT for calculating TEE and PAL was evaluated as valid. A web version of the software program and a smartphone application need to be developed using PACT to make it easier to apply for research purposes.

Effects of packaging method and root trimming on quality of green onion (Allium fistulosum L.) during storage (대파(Allium fistulosum L.)의 포장 방법과 뿌리 손질이 저장 중 품질에 미치는 영향 )

  • Ji Weon Choi;MiAe Cho;Ki-Sik Jung;Jae Han Cho;Ji Hyun Lee;Sooyeon Lim
    • Food Science and Preservation
    • /
    • v.31 no.3
    • /
    • pp.433-443
    • /
    • 2024
  • This study investigated the effect of packaging method and root trimming on quality of green onions during storage. Two packaging methods (tied with string, S or packaged with film bag, FP) and two root trimming states (attaching the roots without trimming, AR or cutting the roots leaving about 5 mm, CR) were treated after harvest. Then, the green onions stored at 20℃ for 8 days and 1℃ for 6 weeks to investigate changes in quality. When stored at 20℃, the differences in marketability between S and FP were minimal, while when stored at 1℃, the marketability of the FP remained higher than that of S. The leaf color change in CR progressed faster than in the AR treatment group, leading to faster quality deterioration. The occurrence of weight loss, browning, and softening of stems progressed as the storage period elapsed. However, except weight loss, they were at a level that did not affect marketability within the marketability limit period determined by color change and wiltig of leaves. The allicin and quercetin contents of stems increased in the early stages when quality deteriorated after harvest but decreased as quality deterioration became more severe.

Effect of surfactant lavage in severe meconium aspiration syndrome (중증 태변 흡인 증후군에서 인공 폐표면활성제 세정요법의 효과에 관한 비교 연구)

  • Lee, Soon Min;Kim, He Min;Jeon, Ji Hyun;Park, Min Soo;Park, Kook In;Namgung, Ran;Lee, Chul
    • Clinical and Experimental Pediatrics
    • /
    • v.51 no.4
    • /
    • pp.367-371
    • /
    • 2008
  • Purpose : The surfactant dysfunction may play an important role in meconium aspiration syndrome (MAS). We aim to evaluate the effect of surfactant lavage in the treatment of term infants with MAS. Methods : The medical records of 15 neonates with severe MAS admitted at Yongdong Severance Hospital from 2005 to 2007 were reviewed and analyzed. Seven infants with severe MAS necessitating mechanical ventilation underwent tracheobronchial lavage with 20 mL/kg of diluted (5.3 mg phospholipid/mL) surfactant saline suspension ($Newfactan^{(R)}$). Data regarding clinical outcomes was assessed by comparison with 8 control infants with equally severe MAS retrospectively. Results : In the lavage group, radiological improvement was evident after 6 hours of treatment. The duration of artificial ventilation and duration of hospital day were also significantly shorten in the lavage group compared with the control group. The mean oxygen index, mean ventilation index improved significantly within the first 6 hours after treatment. No differences were found in the incidence of major complications and mortality between the two groups. Conclusion : The surfactant lavage seems to be an effective and safe method for treatment of severe MAS. A multicenter, large scaled randomized controlled trial is needed for further study.

A Comparative Study of Information Delivery Method in Networks According to Off-line Communication (오프라인 커뮤니케이션 유무에 따른 네트워크 별 정보전달 방법 비교 분석)

  • Park, Won-Kuk;Choi, Chan;Moon, Hyun-Sil;Choi, Il-Young;Kim, Jae-Kyeong
    • Journal of Intelligence and Information Systems
    • /
    • v.17 no.4
    • /
    • pp.131-142
    • /
    • 2011
  • In recent years, Social Network Service, which is defined as a web-based service that allows an individual to construct a public or a semi-public profile within a bounded system, articulates a list of other users with whom they share connections, and traverses their list of connections. For example, Facebook and Twitter are the representative sites of Social Network Service, and these sites are the big issue in the world. A lot of people use Social Network Services to connect and maintain social relationship. Recently the users of Social Network Services have increased dramatically. Accordingly, many organizations become interested in Social Network Services as means of marketing, media, communication with their customers, and so on, because social network services can offer a variety of benefits to organizations such as companies and associations. In other words, organizations can use Social Network Services to respond rapidly to various user's behaviors because Social Network Services can make it possible to communicate between the users more easily and faster. And marketing cost of the Social Network Service is lower than that of existing tools such as broadcasts, news papers, and direct mails. In addition, Social network Services are growing in market place. So, the organizations such as companies and associations can acquire potential customers for the future. However, organizations uniformly communicate with users through Social Network Service without consideration of the characteristics of the networks although networks have different effects on information deliveries. For example, members' cohesion in an offline communication is higher than that in an online communication because the members of the offline communication are very close. that is, the network of the offline communication has a strong tie. Accordingly, information delivery is fast in the network of the offline communication. In this study, we compose two networks which have different characteristic of communication in Twitter. First network is constructed with data based on an offline communication such as friend, family, senior and junior in school. Second network is constructed with randomly selected data from users who want to associate with friends in online. Each network size is 250 people who divide with three groups. The first group is an ego which means a person in the center of the network. The second group is the ego's followers. The last group is composed of the ego's follower's followers. We compare the networks through social network analysis and follower's reaction analysis. We investigate density and centrality to analyze the characteristic of each network. And we analyze the follower's reactions such as replies and retweets to find differences of information delivery in each network. Our experiment results indicate that density and centrality of the offline communicationbased network are higher than those of the online-based network. Also the number of replies are larger than that of retweets in the offline communication-based network. On the other hand, the number of retweets are larger than that of replies in the online based network. We identified that the effect of information delivery in the offline communication-based network was different from those in the online communication-based network through experiments. So, you configure the appropriate network types considering the characteristics of the network if you want to use social network as an effective marketing tool.