Recent growth of children in the two Koreas: A meta-analysis

Height differences between the two Koreas were injected into the U.S. presidential debate. The purpose of this article is to report briefly the height, weight, and body mass index (BMI) differences between North and South Korean children by using previous sources and new data. This study employs South Korean data published by the Korean Research Institute for Standards and Science in 1997 and by the Korean Agency for Technology and Standards in 2004, comparing them to North Korean data stemming from the 1997 and 2002 nutritional surveys conducted by the United Nations. Furthermore, this article makes use of anthropometric measurements of North Korean refugee children immigrating to South Korea from 2000 to 2007. In 1997, South Korean preschool children were found on average to be 6-7 cm (2-3 in.) taller and about 3 kg (6.6 pounds) heavier than their Northern counterparts; in 2002, the average gap was about 8 cm (3 in.) and 3 kg (6.6 pounds), and the BMI gap was about 1. North Korean boys and girls escaping to South Korea were also found to be on average about 3-4 cm (1-1.6 in.) shorter and 1 kg (2.2 pounds) lighter than their Southern peers.     

Alien flora of the Korean Peninsula

The Korean Peninsula has been divided into the countries of North and South Korea since 1948. This adoption of different political and socio-economic regimes has significantly changed economic activity and international exchange by those nations, thus affecting the introduction of alien plants. Our study objective was to provide a comprehensive, up-to-date inventory of the alien flora on the Korean Peninsula and to analyse how the partitioning between North and South Korea has influenced the numbers and status of those alien plants. We identified pre-1876 aliens that were brought to the Korean Peninsula before 1876, when Korea opened up to foreign countries, and also determined the post-1876 aliens that were introduced after 1876. Plants in the latter group were further classified into those that arrived before the outbreak of the Korean War in 1950 (1876–1950 aliens) and those introduced since then (post-1950 aliens). We investigated the regions of origin, family compositions, and invasion status of those alien taxa. In total, 504 alien taxa were identified, with 102 taxa being pre-1876 and 117 being 1876–1950 aliens. After the Korean War, the number of alien plants in South Korea more than doubled (276 taxa), whereas the number reported for North Korea was considerably lower (33 taxa). This might be due to enhanced economic activity and a larger human population in South Korea. Climatic differences as well as variations in the recording intensity for alien flora between North and South Korea may also have contributed to the large contrast in numbers of new alien species recorded during the last decades. Coordinated measures between the two nations are necessary if the spread of invasive alien plants onto the Korean Peninsula is to be reduced.     

Genetic characteristics of Y-chromosome short tandem repeat haplotypes from cigarette butt samples presumed to be smoked by North Korean men

Korea has been divided into South Korea and North Korea for over 70 years. DNA profiles of the North Korean population have never been reported in the Y-chromosome STR Haplotype Reference Database (YHRD; https://yhrd.org). To investigate genetic features of Y-chromosome STR haplotypes of the North Korean population for the first time. Genomic DNA was isolated from 838 cigarette butts assumed to have been smoked by North Korean men and amplified with PowerPlex Y23 (PPY23) kit. Statistical parameters were calculated using Nei’s formula and analysis of molecular variance (AMOVA). Multidimensional scaling (MDS) plot was constructed by the AMOVA tool and neighbor-joining (NJ) tree was constructed by MEGA 6.06. A total of 121 haplotypes were analyzed for PPY23 loci from a sample population. Haplotype diversity and discrimination capacity were 0.9992 and 0.9837, respectively. Genetic diversities ranged from 0.2981 to 0.9716. For the 16 Y-filer loci and eight minimal loci, respectively 90.9 and 82.6% of the matched haplotypes were estimated to belong to haplogroup O, representing the Southeast and East Asian type. The MDS plot and NJ tree indicated that the samples are most closely related to South Korean. In addition, p-value in the pairwise comparison to the South Korean was slightly above statistical significance (p?=?0.0534). The Y-STR haplotypes of the samples were unique and highly genetically polymorphic. Despite the separation between North and South Korea for 70 years, they can still be considered a single genetic population, based on Y-STR haplotypes.     

A History of and Recent Developments Concerning the Korean Peninsula Northern Limit Line (NLL)

Abstract

Measures to ease tensions and prevent military conflicts adjacent to the Korean Peninsula Northern Limit Line (NLL) are an integral part of the ongoing reconciliatory efforts between the South and the North. Despite controversies over the validity of the NLL, it has served as a de facto maritime demarcation line in the absence of an agreed-upon maritime demarcation line under the Armistice Agreement. North Korea has persistently attempted to invalidate the NLL, while South Korea has supported the status quo of the NLL as a military demarcation line. The South and North have recently created a buffer zone across the NLL in the West Sea amid talks for North Korea’s denuclearization.     

Korean Peninsula Maritime Issues

In the unique situation of the Korean Peninsula, which is still technically in a state of war, maritime issues are increasingly becoming critical in the relations between South Korea and North Korea. While cooperation in maritime affairs has helped to ease tensions and paved a way to reconciliatory efforts, maritime disputes adjacent to the Northern Limit Lines in the West and East Seas and maritime security issues such as South Korea's engagement in the Proliferation Security Initiative remain a source of conflict. This article looks at maritime affairs on the Korean Peninsula—a leading area of cooperation between the South and the North as well as a potential conflict flash point.     

The biological standard of living in the two Koreas

Height data of North Korean escapees are analyzed to assess changes in their biological standard of living. In contrast to the population of South Korea, as well as to that of most of the rest of the world, North Koreans did not experience an increase in physical stature during the second half of the 20th century. The divergence between the height of North- and South-Koreans began among the birth cohorts of the late 1940s and became increasingly pronounced thereafter. This is an indication of the adverse socio-economic circumstances prevailing in the northern part of the Korean peninsula.     

Unstable vivax malaria in Korea

Korean vivax malaria had been prevalent for longtime throughout the country with low endemicity. As a result of the Korean war (1950-1953), malaria became epidemic. In 1959-1969 when the National Malaria Eradication Service (NMES) was implemented, malaria rates declined, with low endemicity in the south-west and south plain areas and high endemic foci in north Kyongsangbuk-do (province) and north and east Kyonggi-do. NMES activities greatly contributed in accelerating the control and later eradication of malaria. The Republic of Korea (South Korea) was designated malaria free in 1979. However, malaria re-emerged in 1993 and an outbreak occurred in north Kyonggi-do and north-west Kangwon-do (in and/or near the Demilitarized Zone, DMZ), bordering North Korea. It has been postulated that most of the malaria cases resulted from bites of sporozoite-infected females of An. sinensis dispersed from North Korea across the DMZ. Judging from epidemiological and socio-ecological factors, vivax malaria would not be possible to be endemic in South Korea. Historical data show that vivax malaria in Korea is a typical unstable malaria. Epidemics may occur when environmental, socio-economical, and/or political factors change in favor to malaria transmission, and when such factors change to normal conditions malaria rates become low and may disappear. Passive case detection is a most feasible and recommendable control measure against the unstable vivax malaria in Korea in cost-effect point of view.     

Tissue parasitic helminthiases are prevalent at Cheongjin, North Korea

We investigated a small-scale serological survey to screen tissue-parasitic helminthiases of North Koreans as one of research programs for re-unification of Korea. Soil-transmitted helminthiases were found highly prevalent among North Korean residents at the border with China. ELISA using 4 tissue-parasitic helminth antigens was applied to 137 residents living in Cheongjin-shi, Hamgyeongbuk-do, North Korea and 133 female refugees in South Korea in 2004-2005. Among a total of 270 samples, 31 (11.5%), 25 (9.3%), and 11 (4.1%) were positive for specific IgG antibodies to antigens of Clonorchis sinensis, Taenia solium metacestode, and sparganum, respectively. The overall positive rate was 21.5%; 38.2% in males and 15.8% in females. The present finding suggests that tissue parasites, such as C. sinensis, T. solium metacestode and sparganum are highly prevalent in some limited areas of North Korea. These foodborne tissue-parasitic helminthiases should be considered for future control measures of parasitic diseases in North Korea.     

Genetic diversity and genetic structure of the endangered Manchurian trout, <Emphasis Type="Italic">Brachymystax lenok tsinlingensis</Emphasis>, at its southern range margin: conservation implications for future restoration

The Manchurian trout, Brachymystax lenok tsinlingensis (family: Salmonidae), is a cold freshwater fish endemic to Northeast Asia. South Korean populations of this species, which comprise its southern range limit, have recently decreased markedly in size and are now becoming critically endangered. We assessed the current population status of this species in South Korea by estimating the levels of genetic diversity and genetic structure of five natural and four restored populations using mitochondrial DNA (mtDNA) control region sequences and eight nuclear microsatellite loci. Levels of within-population genetic diversity were low, suggesting that past effective population sizes (N _e) have been small. Each population had one or a maximum of two mtDNA haplotypes. Microsatellite allelic richness (AR) was significantly higher for natural populations (mean AR?=?3.51; 95% confidence interval, 3.00–4.03) than for restored populations (mean AR?=?2.61; 2.38–2.98). South Korean populations were significantly genetically isolated from one another, with private mtDNA haplotypes and microsatellite alleles, suggesting that limited gene flow has been occurring among populations. A mtDNA phylogeny revealed that South Korean lineages were more closely related to those of China than to those of North Korea and Russia. Overall, we suggest that future restoration efforts aimed at South Korean populations should consider the genetic characteristics reported here, which should help to fulfil effective conservation strategies for this highly cherished species. Our results will inform other conservation efforts, including assisted migration of freshwater fish populations at the equatorial end of the geographical range limit of the species.     

Genetic status of Asiatic black bear (Ursus thibetanus) reintroduced into South Korea based on mitochondrial DNA and microsatellite loci analysis

The Asiatic black bear is one of the most endangered mammals in South Korea owing to population declines resulting from human exploitation and habitat fragmentation. To restore the black bear population in South Korea, 27 bear cubs from North Korea and Russian Far East (Primorsky Krai) were imported and released into Jirisan National Park, a reservoir of the largest wild population in South Korea, in 2004. To monitor the success of this reintroduction, the genetic diversity and population structure of the reintroduced black bears were measured using both mitochondrial and nuclear DNA markers. Mitochondrial D-loop region DNA sequences (615 bp) of 43 Japanese black bears from previous study and 14 Southeast Asian black bears in this study were employed to obtain phylogenetic inference of the reintroduced black bears. The mitochondrial phylogeny indicated Asiatic black bear populations from Russian Far East and North Korea form a single evolutionary unit distinct from populations from Japan and Southeast Asia. Mean expected heterozygosity (H(E)) across 16 microsatellite loci was 0.648 for Russian and 0.676 for North Korean populations. There was a moderate but significant level of microsatellite differentiation (F(ST) = 0.063) between black bears from the 2 source areas. In addition, genetic evidences revealed that 2 populations are represented as diverging groups, with lingering genetic admixture among individuals of 2 source populations. Relatedness analysis based on genetic markers indicated several discrepancies with the pedigree records. Implication of the phylogenetic and genetic evidences on long-term management of Asiatic black bears in South Korea is discussed.     

韩国旧石器时代晚期石叶工业的年代与特征

本文介绍了韩国石叶组合的区域特征,并在近期研究的基础上对人类向朝鲜半岛的迁移进行了概述。除了西伯利亚的阿尔泰地区等及华北的水洞沟外,石叶组合在东亚地区的旧石器遗址中十分罕见。1990年底,韩国密阳市的Koreri遗址发现了一个典型的石叶石器工业遗存。在过去的十年间,韩国还发现了数个重要的遗址。朝鲜半岛的砾石石器工业一直持续到旧石器时代晚期的较早阶段,而在大约40kaBP,朝鲜半岛出现了石叶组合。在这些典型的石叶地点中,未发现大多数种类的重型工具。这些特征表明,朝鲜半岛的石叶工业可能是人类迁移的结果。目前还没有证据表明韩国的石叶工具工业在25~10 kaBP被细石叶工业取代,相反,这两种文化可能是由移居朝鲜半岛的不同人群产生的,在细石叶的使用用群体迅速扩散到整个朝鲜半岛时,石叶工业仍然延续,在25~15 kaBP的时间里与细石叶工业并存。     

Microsatellite DNA Analysis Revealed a Drastic Genetic Change of Plasmodium vivax Population in the Republic of Korea During 2002 and 2003

Background

Vivax malaria was successfully eliminated in the Republic of Korea (South Korea) in the late 1970s, but it was found to have re-emerged from 1993. In order to control malaria and evaluate the effectiveness of malaria controls, it is important to develop a spatiotemporal understanding of the genetic structure of the parasite population. Here, we estimated the population structure and temporal dynamics of the transmission of Plasmodium vivax in South Korea by analyzing microsatellite DNA markers of the parasite.

Methodology/Principal Findings

We analyzed 14 microsatellite DNA loci of the P. vivax genome from 163 South Korean isolates collected from 1994 to 2008. Allelic data were used to analyze linkage disequilibrium (LD), genetic differentiation and population structure, in order to make a detailed estimate of temporal change in the parasite population. The LD analysis showed a gradual decrease in LD levels, while the levels of genetic differentiation between successive years and analysis of the population structure based on the Bayesian approach suggested that a drastic genetic change occurred in the South Korean population during 2002 and 2003.

Conclusions/Significance

Although relapse and asymptomatic parasite carriage might influence the population structure to some extent, our results suggested the continual introduction of P. vivax into South Korea through other parasite population sources. One possible source, particularly during 2002 and 2003, is North Korea. Molecular epidemiology using microsatellite DNA of the P. vivax population is effective for assessing the population structure and temporal dynamics of parasite transmission; information that can assist in the elimination of vivax malaria in endemic areas.     

Disciplinary citizenship in South Korean NGOs' narratives of resettlement for North Korean refugees

This article explores how non-governmental organizations (NGOs) in South Korea articulate and implement disciplinary citizenship in the resettlement of North Korean refugees. Fieldwork based on in-depth interviews reveals that NGOs play a pivotal role in carrying out the state-led resettlement project at the local level. As disciplinary agents, NGOs mirror the state's policy in their emphasis on self-sufficiency and workfare as they encourage North Koreans to become economically productive citizens. Concomitantly, they emphasize civic contributions and volunteerism as a remedy for improving the social reputation of North Koreans as welfare recipients to that of contributing citizens. This focus on active, responsible citizenship aims at disciplining North Koreans to become docile subjects at the bottom of the social ladder, despite persistent economic difficulties and social marginalization in South Korea. Thus, refugees are pressured not only to achieve economic self-sufficiency, but to contribute to society in order to claim their sociocultural citizenship.     

Invasion pathway of the honeybee pest,small hive beetle,Aethina tumida (Coleoptera: Nitidulidae) in the Republic of Korea inferred by mitochondrial DNA sequence analysis

The small hive beetle (SHB), Aethina tumida, is native to the Sub-Saharan region of Africa, but it became invasive in many countries after its first introduction to the USA in 1996. The SHB is a destructive pest of the honey industry and can cause damage in apiaries due to feeding on the honey, pollen, honey bee brood and honey fermentation. SHB was recently found infesting honeybee colonies in the South-Eastern part of Korea, Miryang city in 2016. No inference of the origin or the pathway of the invasion into Korea has been made, so far. We analyzed partial cytochrome oxidase I gene of mitochondrial DNA to unveil the possible source of the invasive populations of SHB in South Korea. A Bayesian inference tree and median joining haplotype network revealed a strong relationship between South Korean and North American populations suggesting that the SHB in South Korea came from the USA. Low genetic variation among Korean populations suggests that the invasion might have occurred in a single event with small number of founders. In addition, a new global distributional map of SHB is provided.     

The current state of korean paleoanthropology

The hominid fossil and Paleolithic archaeology records from the Korean Peninsula are extensive, but relatively little is known about the Korean human evolutionary record outside this region. The Korean paleoanthropological record is reviewed here in light of major research issues, including the hominid fossil record, relative and chronometric dating, lithic analysis, hominid subsistence, and the presence of bone tools, art and symbolism. Some of the major conclusions drawn from this review include: (1) hominid fossils have been found in nine separate sites on the Korean Peninsula; (2) possible Homo erectus fossils are present in North Korea; (3) Ryonggok Cave, in North Korea, has exposed the remains of at least five archaic Homo sapiens individuals; (4) a possible burial of an anatomically modern Homo sapiens child, discovered in Hungsu Cave in South Korea, has been tentatively dated to roughly 40,000 years ago; (5) handaxes and cleavers have been found at a number of sites near Chongokni and they appear to date to at least 100,000 years ago; and (6) taphonomic studies are necessary for addressing issues related to determining the nature of hominid-carnivore interaction over similar resources (e.g. carcasses and shelter); and the presence/absence of Early Paleolithic bone tools, art, and symbolism in Korea.     

Reemerging vivax malaria: changing patterns of annual incidence and control programs in the Republic of Korea

Changing patterns of the reemerging Plasmodium vivax malaria in the Republic of Korea (South Korea) during the period 1993 to 2005 are briefly analyzed with emphasis on the control measures used and the effects of meteorological and entomological factors. Data were obtained from the Communicable Diseases Monthly Reports published by the Korea Center for Disease Control and Prevention, and webpages of World Health Organization and United Nations. Meteorological data of Kangwon-do (Province) were obtained from local weather stations. After its first reemergence in 1993, the prevalence of malaria increased exponentially, peaking in 2000, and then decreased. In total, 21,419 cases were reported between 1993 and 2005 in South Korea. In North Korea, a total of 916,225 cases were reported between 1999 and 2004. The occurrence of malaria in high risk areas of South Korea was significantly (P > 0.05) correlated with the mosquito population but not with temperature and rainfall. Control programs, including early case detection and treatment, mass chemoprophylaxis of soldiers, and international financial aids to North Korea for malaria control have been instituted. The situation of the reemerging vivax malaria in the Republic of Korea is remarkably improving during the recent years, at least in part, due to the control activities undertaken in South and North Korea.     

Plant communities dominated by Salix gracilistyla in Korean Peninsula and Japan

Riverside vegetation dominated by Salix gracilistyla was analysed. In total, 77 phytocoenological relevés from Japan and both Korean Republics were compared. Based on 20 own relevés from Kumgang-san Mts (North Korea) a new association Artemisio feddei-Salicetum gracilistylae was described. It occupies alluvia of rivers and streams flooded for several times yearly. This species-rich community differs from the most similar, but species-poor association Salicetum gracilistylae Minamikawa 1963, described from Japan and known also from South Korea by numerous differential taxa.     

Molecular phylogeny and biogeography of the Korean woodroaches Cryptocercus spp

Phylogenetic relationships and biogeography of Northeast Asian Cryptocercus were inferred based on the DNA sequences of mitochondrial COII and 16S rRNA genes and nuclear 18S rRNA gene. The results suggest that two clades exist in Korean populations. The southwestern population (Cryptocercus from Jiri-san) was more closely related to the populations from Northeast China and eastern Russia than to all the other Korean Cryptocercus. According to molecular-based estimated divergence times, the divergence event occurred between Cryptocercus in Jiri-san, Northeast China and eastern Russia and those in the remaining South Korea during the Miocene (7.5-17.4Myr ago), and then the divergence event between Cryptocercus in Jiri-san and those in Northeast China and eastern Russia occurred 0.8-1.9Myr ago. In the Korean Peninsula, Jiri-san is located in the most southwestern region among the high mountains surveyed. The location is the farthest from Northeast China and eastern Russia among sampling localities in South Korea. Thus, it was unexpected that the southwestern populations are more closely related to those from Northeast China and eastern Russia rather than to the other Korean Cryptocercus. Based on Korean topography and estimated divergence times, possible scenarios are proposed for the current geographical distribution of Korean Cryptocercus.     

Microsatellite DNA analysis reveals lower than expected genetic diversity in the threatened leopard cat (<Emphasis Type="Italic">Prionailurus bengalensis</Emphasis>) in South Korea

To optimize conservation efforts, it is necessary to determine the risk of extinction by collecting reliable population information for a given species. We developed eight novel, polymorphic microsatellite markers and used these markers in conjunction with twelve existing markers to measure genetic diversity of South Korean populations of leopard cat (Prionailurus bengalensis), a species for which population size and habitat area data are unknown in the country, to assess its conservation status. The average number of alleles and the observed heterozygosity of the species were 3.8 and 0.41, respectively, and microsatellite diversity was lower than the average genetic diversity of 57 populations of 12 other felid species, and lower than that of other mammal populations occurring in South Korea, including the raccoon dog (Nyctereutes procyonoides), water deer (Hydropotes inermis), and endangered long-tailed goral (Naemorhedus caudatus). Furthermore, analysis of genetic structure in the national leopard cat population showed no clear genetic differentiation, suggesting that it is not necessary to divide the South Korean leopard cat population into multiple management units for the purposes of conservation. These results indicate that the genetic diversity of the leopard cat in South Korea is unexpectedly low, and that the risk of local extinction is, as a result, substantial. Thus, it is necessary to begin appropriate conservation efforts at a national level to conserve the leopard cat population in South Korea.     

Trends in butterfly species richness in response to the peninsular effect in South Korea

Aim The Korean peninsula is elongated in shape and is connected to the Asian continent on the north. The peninsular effect – a decline in species density or richness as a function of distance from the mainland base (towards the distal tip) of a peninsula – was evaluated for plants and animals in different peninsulas. The aims of the present study were to describe the pattern of butterfly species diversity and to determine what factors may be responsible for this pattern along the Korean peninsula. The distribution pattern of butterfly species in South Korea before and after the Korean War was also investigated. Location South Korea (34–38° N, 126–129° E). Methods Forty‐three quadrats, each 1/2° latitude by 1/2° longitude, and three data sets – butterfly distribution data from 1938 to 1950, butterfly distribution data from 1976 to 1999, and the combined data – were analysed. The influence of four variables – latitude, longitude, area and maximum altitude – on each quadrat was investigated using multiple regression analysis. Results and conclusion The analyses revealed a marked peninsular effect: there was a significant positive correlation between butterfly species richness and latitude. Additionally, habitat diversity, expressed as maximum altitude, was significantly correlated with butterfly species richness. I conclude that both the geographical orientation and habitat diversity contribute to butterfly species diversity across South Korea. Comparison of ranges between the older and recent data sets suggests that geographical distributions of several species are dramatically reduced in size. These species may be used for future conservation activities in South Korea.