• Animal Systematics, Evolution and Diversity
• /
• v.36 no.2
• /
• pp.154-158
• /
• 2020

The Asian crested ibis Nipponia nippon is one of the world's most endangered species. Except for the Sanxii population from China, it is known that all of the crested ibis populations from East Asia have been extinguished. In these days, most of them are being inbred as captive populations in China, South Korea, and Japan, which caused their low expected genetic diversity. Microsatellite markers are well known as a suitable DNA marker for exploring genetic diversity among captive populations of a variety of endangered species. In the present study, ten microsatellite markers were developed for the captive populations of the South Korean crested ibis, which were employed to examine the level of genetic diversity with the two founders from Sanxii, China and the 70 descendants of them. As a result, the mean number of gene diversity, observed heterozygosity, and expected heterozygosity of the captive population were 0.70, 0.84, and 0.70 respectively. It revealed that the captive population of South Korea is as genetically more stable than we expected. In addition, the principal coordinates analysis and genetic structure analyses showed that the captive population of N. nippon can be divided into the two different genetic groups. The developed microsatellite markers here could be helpful for crested ibis conservation in East Asian countries such as China and Japan as well as South Korea.

• Annals of Hepato-Biliary-Pancreatic Surgery
• /
• v.28 no.3
• /
• pp.371-380
• /
• 2024

Backgrounds/Aims: The published data had contradictory information on the role of adjuvant therapy on resected periampullary carcinomas (PACA). The study was performed to evaluate the survival benefit of adjuvant treatment. Methods: This was a propensity score matched case-control study from a prospectively maintained database from 2004-2019. The study included patients with nonpancreatic PACA who underwent curative resection. The patients (cases) who received adjuvant chemotherapy were compared with patients (controls) who were observed alone after surgery. Results: Of 510 patients with PACA, 230 patients (cases = 107, controls = 123) formed the unmatched study cohort. After propensity score matching, 140 patients (cases = 70, controls = 70) formed the matched study cohort. The median overall survival (OS) was similar in cases than controls in the unmatched population but doubled non-significantly in cases after matching (unmatched population, 54 months vs. 54 months, p-value = 0.624; matched population, 71 months vs. 36 months, p-value = 0.087). However, the median recurrence-free survival (RFS) was non significantly higher in the control group (unmatched population, 59 months vs. 38 months, p-value = 0.195; matched population, 53 months vs. 40 months, p-value = 0.797). In cox regression analysis, age < 60 years, advanced T stage, and presence of perineural invasion were independent factors for worse RFS, while tumor recurrence was an independent factor for poor OS. Conclusions: Patients with nonpancreatic PACA may have an OS benefit from adjuvant chemotherapy, and this needs to be validated with large prospective randomized studies.

• Korean Journal of Adult Nursing
• /
• v.16 no.2
• /
• pp.245-255
• /
• 2004

Purpose: this study was to evaluate Cognitive Function Test for the Korean population. Digit Forward (DF), Digit Backward (DB) and Trail Making Test-A(TMT-A) and the translated version of the Trail Making Test-B (TMT-B) were used. The study examined the performance of Korean normal adult population whose age ranged from 20 to over 80. It was predicted that performances of the Korean population would be different from that of the United States population due primarily to their differences in language, and education. Method: Normal Korean adults at the Daejeon Metropolitan City and Chungchung Province (N=298) participated in this study. Seven age scores were evaluated; 20~29, 30~39, 40~49, 50~59, 60~69, 70~79, & >80s. The effects of age, gender, and years of education was examined, which yielded significant age and education effects. The scores were further specified accordingly in terms of years of education (0, 1~6, 7~12, 13~16, & >17), and gender. Result: As the age increased cognitive function score decreased. As the years of education increased, cognitive function scores increased. There was no difference in cognitive function scores according to gender. Age and year of education had significant effects on cognitive function and explained 52-58% of variants of each test. Conclusion: The data of the cognitive function tests are expected to be utilized for research purposes such as basic and clinical studies, as well as practical purpose such as cognitive assessment for traumatic brain injury, stroke, and elderly and nursing education for assessment tools.

• Korean Journal of Health Education and Promotion
• /
• v.6 no.2
• /
• pp.58-65
• /
• 1989

This study analyzes the structural characteristics of rapid changes in Korean population, using the data of a census and other data on the changes in the population. Major findings are : 1. During 1950~1955, annual increase rate of population was about 1.02%, about 2.88% during 1955~1960, and 1.36% during 1980~1985. It is expected to decrease to 0.07% during 2015~2020. 2. Major Age Composition 0~14 is expected to reduce to 16.5% in 2020 from 41.2% in 1955, while the ratio of population aged 15~64 is expected to increase to 72.1% from 55.5%. Furthermore, for the population group of age 65 and over is expected to increase from a mere 3.3% to 11.4%. 3. The aging index of population is expected to increase to 69.5 in 2020 from 8.0 in 1955 and so the old dependency ratio is expected to 15.9 from 6.0 4. The median age is expected to 40.2 in 2020 from 19.0 in 1955. 5. In 2020 the child-woman ratio is expected to reduce to 22.3 from 64.7 in 1955. 6. In 2020 the age index of 0~4 is expected to 57.4 from 169.4 in 1955, and the age index of 65~69 to 261.7 from 95.6 on the contrary.

• Animal Bioscience
• /
• v.34 no.4
• /
• pp.525-532
• /
• 2021

Objective: Old World camels are a valuable genetic resource for many countries around the world due to their adaptation to the desert environment. At present, Old World camels have encountered the challenge of unprecedented loss of genetic resources. Through our research, we would reveal the population structure and genetic variation in Old World camel populations, which provides a theoretical basis for understanding the germplasm resources and origin and evolution of different Old World camel populations. Methods: In the present study, we assessed mtDNA control region sequences of 182 individuals from Old World camels to unravel genetic diversity, phylogeography, and demographic dynamics. Results: Thirty-two haplotypes confirmed by 54 polymorphic sites were identified in the 156 sequences, which included 129 domestic and 27 wild Bactrian camels. Meanwhile, 14 haplotypes were defined by 47 polymorphic sites from 26 sequences in the dromedaries. The wild Bactrian camel population showed the lowest haplotype and nucleotide diversity, while the dromedaries investigated had the highest. The phylogenetic analysis suggests that there are several shared haplotypes in different Bactrian camel populations, and that there has been genetic introgression between domestic Bactrian camels and dromedaries. In addition, positive values of Tajima's D and Fu's Fs test demonstrated a decrease in population size and/or balancing selection in the wild Bactrian camel population. In contrast, the negative values of Tajima's D and Fu's Fs test in East Asian Bactrian camel populations explained the demographic expansion and/or positive selection. Conclusion: In summary, we report novel information regarding the genetic diversity, population structure and demographic dynamics of Old World camels. The findings obtained from the present study reveal that abundant genetic diversity occurs in domestic Bactrian camel populations and dromedaries, while there are low levels of haplotype and nucleotide diversity in the wild Bactrian camel population.

• Proceedings of The Korean Society of Health Promotion Conference
• /
• 1999.07a
• /
• pp.117-128
• /
• 1999

Before considering health promotion programs carried out in Japan, I would like to explain a summary of today's health conditions of Japan for a while. Current major concern in public health world as well as political or economic world is an aging society. To say more precisely, it would be an aging society with relatively small children's population. Estimated total population is 126,166,000 in 1997. Among these, almost 10% population lives in Tokyo Metropolitan Area.(omitted)

• Research in Mathematical Education
• /
• v.25 no.1
• /
• pp.45-63
• /
• 2022

Multicultural students are a rapidly growing population in South Korea. Previous studies from the South Korean mathematics education community have reported low mathematics achievement levels of this population compared to Korean-born students. However, a systematic literature review was hardly employed. This study aims to synthesize the factors that affect the mathematics achievement of multicultural students to provide directions for future research and practical directions. Using an Opportunity-Propensity framework suggested by Byrnes and Miller, this study analyzed twenty-seven peer-reviewed journal articles on this topic. The results showed that the majority of the studies focused on the impact of the opportunity factors such as mathematics curriculum and teachers on mathematics achievements. We suggest that more studies regarding distal factors (e.g., students' prior achievement) and propensity factors (e.g., prerequisite knowledge) are needed.

• Korean Journal of Environmental Biology
• /
• v.27 no.1
• /
• pp.20-30
• /
• 2009

To study reproductive dynamics of a Gold-spotted pond frog (Rana chosenica) population located at Gangnae, Cheongwon, Chungbuk, Korea, we monitored the population over 207 days between April 17$^{th}$ 2007 and December 18$^{th}$ 2008 using a drift fence accompanied with 20 pitfall traps. The population was located in an agricultural wetland, compromising three small ponds. Gold-spotted pond frogs immigrated into the wetland between April 16$^{th}$ and June 17$^{th}$ and emigrated from the wetland between September 21$^{st}$ and November 12$^{th}$. Precipitation showed a positive correlation with the number of migrated frogs in Autumn 2007 and Spring 2008, but other environmental factors such as air and water temperatures and relative humidity did not show any significant relationships. In general, small frogs first migrated into and from the wetland, but the trend was not strong. Female gold-spotted pond frogs were bigger than males. During the autumn migration, small frogs of which snout-vent length was smaller than 20 mm were found, indicating that successful breeding occurred in the population. Our results could be useful to conserve this endangered species in Korea.

• Korean Institute of Interior Design Journal
• /
• v.14 no.3 s.50
• /
• pp.156-164
• /
• 2005

Like other countries undergoing the aging of the population, increases in the aged population have raised serious issues in Korea. The proportion of elderly will be foreseen over $14\%$ of population in 2019, over $20\%$ in 2026 in korea. Due to the rapid increasing in the aged population, it calls for social countermeasures urgently, And recent researches about attitude to the aged find out in general negative attitude to the aged of other generations. It is thought desirable that comprehension to the aged of the commonalty should be educated on the school basis or a variety of informal ways. The study aims to determine the space formation of the senior simulation center that suggest to be considered for the effective education and preparation for the aging of all social members, particularly for the younger generation. In such space formation, it is important to work out a plan of efficiency education according to the systematic environmental setting with a focus on the minimization of problematic behaviors and living disabilities of aging, as interactive experiences gain malfunctions by aging. This study is expected to promote a focus on the integration of the whole generations and improved design management for the environment of a welfare policy for the aged.

• Proceedings of the Zoological Society Korea Conference
• /
• 1997.10b
• /
• pp.290.2-290
• /
• 1997

No Abstract, See Full Text