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The Yeongnam Massif is located in the southern part of the Korean Peninsula and holds key elements in understanding the Palaeoproterozoic tectonic evolution of north‐east Asia during the amalgamation of the Columbia supercontinent. In this study, we have conducted geochronological and geochemical studies on the mafic intrusive along the northern margin of the Yeongnam Massif. Sensitive high‐resolution ion microprobe (SHRIMP) U–Pb zircon dating on two amphibolite and one gabbro samples in the Damyang area show that the amphibolites crystallized at ~1.87 Ga and the gabbro crystallized at ~87.6 Ma. The 1.87 Ga Damyang amphibolites are simultaneous with the Muju and Okbang amphibolites along the northern margin of the Yeongnam Massif. They also show similar geochemical characteristics, including tholeiitic basalt composition, enriched Light Rare Earth Elements (LREE) and large ion lithosphile elements (LILEs), depleted high field strength elements (HFSEs), and slightly enriched but various Hf isotopes, indicating that they originated from an enriched but heterogeneous mantle source with fluid addition. Thus, the 1.87 Ga amphibolites along the northern margin of the Yeongnam Massif were probably emplaced in an arc‐related setting. Combined with the 2.02–1.96 Ga magmatism, it is proposed that the subduction might have lasted during the 2.02–1.85 Ga interval and mantle‐derived magma rose up due to the roll‐back process between 1.88–1.85 Ga. [ABSTRACT FROM AUTHOR]

The Korean Peninsula mainly comprises the Paleoproterozoic Gwanmo, Nangnim, Gyeonggi, and Yeongnam massifs from north to south. The Paleoproterozoic basement is rarely exposed in the Paleozoic Taebaeksan basin, which is located in the northeastern part of the Okcheon belt between the Gyeonggi and Yeongnam massifs. One of the most important issues in the tectonic interpretation of the Korean Peninsula is whether Paleoproterozoic rocks in the Taebaeksan basin have an affinity with those in the Gyeonggi or Yeongnam massifs. To solve this problem, we focused on the petrogenesis of the Imgye gabbroic diorite, Jungbongsan granite, and Jangsan quartzite in the Imgye area of the Taebaeksan basin. The Imgye gabbroic diorite shows mafic to intermediate compositions with slightly enriched LREEs compared to HREEs, slightly positive Rb, K, and Pb anomalies, and negative Ta, Nb, and P anomalies. The Imgye gabbroic diorite formed in a volcanic arc tectonic setting. The geochemical compositions of the Jungbongsan granite show enriched LREEs compared to HREEs with negative Eu anomalies, and reveal strong positive Rb, Th, K, and Pb anomalies with negative Ba, Ta, Nb, Sr, P, Eu, and Ti anomalies. This Jungbongsan granite also formed in an arc tectonic setting like the Imgye gabbroic diorite. LA-ICP-MS zircon age dating of the Imgye gabbroic diorite gives an intrusion age of 1948 ± 21 Ma, whereas SHRIMP U–Pb zircon age dating on the Jungbongsan granite yields an emplacement age of 1873 ± 14 Ma. The εHf(t) values of the Imgye gabbroic diorite are from 3.5 to 9.7, whereas those of the Jungbongsan granite are from −2.9 to 0.6. These data imply that the Imgye gabbroic diorite formed from a depleted mantle in the arc tectonic environment, whereas the Jungbongsan granite formed by reworking pre-existing crust material in the arc environment. The detrital zircons in the Jangsan quartzite show ages ranging from 3.06 to 1.85 Ga, with a peak concentration of ca. 2.5 Ga. Previous studies have suggested that the northern Gyeonggi and Nangnim massifs underwent collision-related magmatism and metamorphism at ca. 1.93–1.90 Ga, and then post-collisional magmatism and metamorphism at ca. 1.89–1.83 Ga, whereas the southern Gyeonggi massif underwent subduction-related magmatism and metamorphism at ca. 1.94–1.92 Ga, and then post-collision-related magmatism and metamorphism at ca. 1.84–1.78 Ga. By contrast, subduction-related events were recognized in the northern Yeongnam massif at ca 2.02–1.96 Ga and 1.90–1.85 Ga. This work, combined with the previous studies, suggests that the Paleoproterozoic basement in the Imgye area of the Taebaeksan basin can be correlated with the Paleoproterozoic basement of the northern Yeongnam massif rather than with those of the Nangnim and Gyeonggi massifs. [ABSTRACT FROM AUTHOR]

The southwestern Gyeonggi Massif features many faults. The main faults are NE-striking faults, including the Jeonju and Kwangju faults, and they are cut by N-S- and NNE-striking faults. Additionally, E-W-, WNW-, and NW-striking faults occur as minor faults. Historical earthquakes with magnitudes greater than 5.0 have occurred on or near these faults. Earthquakes with focal depths shallower than 12 km have generally occurred on the NE-, NNE-, and N-S-striking faults, while those with hypocenters deeper than 12 km have occurred on the NW-, WNW-, and NE-striking faults or do not show a relationship with any faults. The instrumental earthquakes with magnitudes greater than 5.0 in the Korean Peninsula mainly have hypocenters deeper than 12 km, and their epicenters form a NW-oriented trend. These data effectively reflect two seismogenic layers with a boundary at ca. 12 km, as suggested in a previous study. The recent earthquake in the Haenam area occurred in the lower seismogenic layer. The shallower earthquakes seem to be the result of the reactivation of pre-existing faults. In comparison, the deeper earthquakes tend to occur on recently formed or newly formed faults related to the present regional stress of the Korean Peninsula. The shear-wave velocity tomography of the southwestern Gyeonggi Massif at 1 km corresponds well to the geology. In contrast, the shear-wave velocity variations at 5–9 km generally correspond to the locations of brittle faults. The depth of the ~3.5 km/s isovelocity line is quite irregular and is deeper in areas with active fault movement. In the Gyeongsang basin, the relationship between the shear-wave velocity and faults is somewhat unclear because the thickness of low-density sedimentary rocks is up to 8 km. Shear-wave velocity tomography at 13 km can be used to identify areas with high shear stress. These data indicate that shear-wave velocity tomography may provide different information depending on the depth and that the brittle faults in this region may not extend to a depth of 13 km. [ABSTRACT FROM AUTHOR]

• Nangrim and northern Gyeonggi Massif can be correlated to Jiao-Liao-Ji belt. • Southern Gyeonggi Massif may not be correlated to northern Gyeonggi Massif. • Sobaeksan Gneiss Complex cannot correlated to Nangrim Massif. Correlation of the Paleoproterozoic rocks of the Korean Peninsula and China has been considered to be important for the tectonic evolution of Northeast Asia, yet it is still unclear. Recently considerable new data have been obtained from the Korean Peninsula and China providing a better opportunity to correlate the Paleoproterozoic rocks of the Korean Peninsula and China. Intermediate–P/T metamorphism and post–collisional magmatism have been found to have occurred during ca. 1.95–1.83 Ga not only in the Jiao–Liao–Ji belt on the eastern North China Craton but also in the Nangrim and northern Gyeonggi Massifs within the Korean Peninsula representing that these Paleoproterozoic rocks can be correlated. These events occurred as a result of the collision between the Longgang Block of the eastern North China Craton and the Nangrim Massifs of the Korean Peninsula. On the other hand, the southeastern Gyeonggi Massif underwent an arc–related magmatic and metamorphic events during ca. 1.96–1.91 Ga suggesting that the Paleoproterozoic rocks in southeastern Gyeonggi Massif cannot be correlated with those in northern Gyeonggi Massif. The Yeongnam Massif is unlikely correlated to the Nangrim and northern Gyeonggi Massifs and the eastern North China Craton because arc–related igneous activity occurred during ca. 2.00–1.85 Ga in the Sobaeksan Gneiss Complex in the central to northeastern Yeongnam Massif. The Jirisan Gneiss Complex in the southwestern Yeongnam Massif underwent intermediate–P/T metamorphism that is followed by post–collisional magmatic and low–P/T metamorphic events during ca. 1.92–1.86 Ga and these events may be correlated to those in the eastern Cathaysia Block on the South China Craton. The Paleoproterozoic correlation between the Korean Peninsula and China in this study supports a tectonic model in which the Permo–Triassic Dabie–Sulu continental collision belt in China extends into the Hongseong–Odaesan collision belt in the Gyeonggi Massif within the Korean Peninsula. [ABSTRACT FROM AUTHOR]

The Hongcheon-Chuncheon areas located in the northern Gyeonggi Massif on the Korean Peninsula consist of Neoarchean (ca. 2.61–2.49 Ga) and middle Paleoproterozoic (ca. 2.09 Ga) metagranitoids, the Euiam Gneiss Complex (ca. 1.89–1.87 Ga), and metasedimentary units, including the Yongduri Gneiss Complex and Euiam Group. The Neoarchean metagranitoids intruded at ca. 2.61–2.49 Ga and underwent polymetamorphism at ca. 1.92–1.87 Ga and 229 Ma. Whole-rock geochemical data indicate that they were formed by partial melting of low-K mafic rock in the lower crust due to heat supplied from the underplated mafic magma chamber in the arc tectonic setting. The Paleoproterozoic metagranitoids are classified into three types based on geochronology and whole rock chemistry: ca. 2.09 Ga, ca. 1.90 Ga, and ca. 1.89–1.87 Ga metagranitoids that formed in an arc tectonic setting, a syn-collisional tectonic setting, and a post-collision tectonic setting, respectively. The Paleoproterozoic 1st stage metasedimentary rocks (paragneisses) deposited in the Yongduri Gneiss Complex experienced Paleoproterozoic metamorphism, whereas the 2nd stage metasedimentary rocks deposited in the Euiam Group did not experience Paleoproterozoic metamorphism. The 1st stage metasedimentary rocks (paragneisses) were deposited after 2.05–1.95 Ga in an arc tectonic setting; they experienced intermediate-P/T metamorphism (780–860 °C/8.7–11.0 kbar) at ca. 1.91 Ga and then low-P/T metamorphism (710–750 °C/6.0–6.5 kbar) at ca. 1.86 Ga. The 2nd metasedimentary rocks were deposited after ca. 1.88–1.83 Ga and metamorphosed at ca. 234–230 Ma. Together with previous data, these data indicate that the Hongcheon-Chuncheon areas have Archean remnants and experienced similar Paleoproterozoic tectonothermal events recognized from the Jiao-Liao-Ji Belt formed by the collision between the Longgang Block of the North China Craton and the Nangrim Massif of the Korean Peninsula, suggesting that the northern Gyeonggi Massif can be correlated to the North China Craton. [ABSTRACT FROM AUTHOR]

Most Cretaceous igneous rocks in the northeastern North China Cratons (NCC) and southeastern South China Cratons (SCC) in Northeast Asia are interpreted to have formed in the extensional tectonic environment caused by subducted slab roll-back. On the other hand, the Cretaceous magmatism in the proto-Southwest Japan was confirmed to have occurred in the compressional state produced by the paleo-Pacific plate subduction. The granitoids and enclaves in the northern Gyeonggi Massif intruded at ca. 110–109 Ma and 112 Ma respectively, and the granite and pyroclastic rock in the northcentral Yeongnam Massif were formed at 106 Ma and 103 Ma respectively. The enclaves in the Ganghwa area which located in northern Gyeonggi Massif have high whole-rock Sr isotope composition (0.70748–0.71181) and low whole-rock εNd(t) (−14 to −15) value and low zircon εHf(t) (−19.2 to −14.7) values with enrichment of LILE, suggesting their origin from enriched lithospheric mantle metasomatized by subducted slab sediment. The Early Cretaceous granitoids on the northern Gyeonggi and northcentral Yeongnam massifs have adakite like geochemical composition which are derived from the lower crust instead of subducted oceanic crust derived melt. The geochemical features of the Early Cretaceous igneous rocks in the Korean Peninsula including the study area imply that the Early Cretaceous magmatism on the Korean Peninsula mainly occurred in the extension regime caused by slab roll-back of the paleo-Pacific plate as in the NCC. On the other hand, the igneous rocks formed at 80–66 Ma in the Korean Peninsula have geochemical characteristics similar to that in the Cretaceous igneous rocks in proto-Southwest Japan, indicating that the 80–66 Ma magmatism in the Korean Peninsula were produced by the subduction of the paleo-Pacific plate. The Cretaceous igneous rocks in the northeastern NCC and on the Korean Peninsula show a southeastward-younging trend from 145 Ma to 80 Ma, indicating that southeastward slab roll-back had started at 145 Ma and continued until 80 Ma. Arc-related igneous activity occurred from 116 Ma in southwestern Japan and propagated northward, resulting arc related magmatism in the northern margin of proto-southwestern Japan and the southeastern margin of the Korean Peninsula at 80–66 Ma. [Display omitted] • Enriched lithospheric mantle origin of Early Cretaceous Ganghwa enclave. • Melting of lower crust related adakitic signature in the granitoids. • 120–100 Ma Extension related magmatism in the Korean Peninsula (KP). • Southeastward younging trend from 145 Ma in North China Cratons to 80 Ma in KP. • 80–66 Ma arc related magmatism in the southeastern margin of KP. [ABSTRACT FROM AUTHOR]

In this retrospective cohort study, we compared the survival of patients detected by screening with those detected based on symptoms, according to their tumor stages. After propensity score matching, 2,130 patients with papillary or follicular thyroid cancer, identified by screening detection (SD) and clinical detection (CD), were included. We compared the survival rates of patients identified by SD and CD in the early and advanced stages of thyroid cancer. Cox proportional hazard models were used to compare the hazard ratios (HRs) for mortality between the two groups. Of the 1,065 patients in each group, 12 (1.1%) died in the SD group, compared to 44 (4.1%) in the CD group, during an average 9.4 years (p<0.001). For early stage, there was no significant difference in all-cause and thyroid cancer-specific mortality between the two groups (p = 0.08, p = 0.0502). However, for advanced stage, the survival rates in the SD group were significantly higher than in the CD group (p<0.001, p = 0.004). Moreover, after adjusting for covariates, the HRs of all-cause mortality of the SD group was significantly lower than that of the CD group for the advanced stage patients (HRs: 0.37 [95% CIs: 0.17–0.80]), while no significant difference was observed in the early stage. While screening for thyroid cancer was not beneficial for early stage patients, our findings suggest that detection via screening is associated with better survival for patients with advanced stage cancer. However, the effects of selection bias and lead time bias could not be entirely excluded. [ABSTRACT FROM AUTHOR]

The Meso-Neoproterozoic Gubongsan group in the Chuncheon area of the northern Gyeonggi massif in the southern Korean Peninsula was studied to check its correlation with the Meso-Neoproterozoic rocks of the Sangwon system in the northern Korean Peninsula and those of the Qingbaikou system in the southeastern margin of the North China craton. The Gubongsan group consists of the Pyeongchonri, Siniri, and Gamjeongri formations and the upper limit of sedimentation ages of each formation are 1058 Ma, 978 Ma, and 845 Ma, respectively. The detrital zircons in the Pyeongchonri and Siniri formations have two age peaks of ∼1.6–1.5 Ga and 1.2–1.1 Ga. The detrital zircons in the Gamjeongri formation has an age peak of 0.9 Ga. The Gubongsan group was intruded by metabasite and meta-intermediate rock ca. 888–795 Ma. To the south of the Gubongsan group, metabasite intruded ca. 910 Ma. These igneous rocks are plotted in the within-plate basalt field and have enriched LREE without negative Nb, Ta, and Ti anomalies. They show ε Hf (t) values from −1.72 to 14.10 and are plotted between E -MORB and OIB within the MORB array, representing that they formed from the juvenile mantle. This study represents that the sedimentation in the Gubongsan group occurred during Neoproterozoic in the extensional rifting environment with igneous activities in the later stage of extension. The metabasite in the Gubongsan group shows similar Neoproterozoic emplacement age and extension-related geochemical characteristics to the Sariwon sill in the Sangwon system located in the southern Nangnim massif, and the Dalian and Chulan sills in the Qingbaikou system of the southeastern margin of the North China craton. Not only the correlation of metabasite but also the youngest age of the detrital zircons and age provenance in the sedimentary rocks of the Gubongsan group are similar to those of the Sangwon system and the Qingbaikou system. This study represents that the Meso-Neoproterozoic rocks in the Gubongsan group can be correlated with those in the Sangwon system and the Qingbaikou system. These correlations indicate that the northern Gyeonggi massif can be correlated with the southern Nangnim massif and the southeastern margin of the North China craton. • The Meso-Neoproterozoic Gubongsan Group occurs in the northern Gyeonggi massif. • Rift-related metabasite intruded the Gubongsan Group (GG) during 888–795 Ma. • The GG can be correlated to the Sangwon system in the southern Nangnim massif. • The GG can be correlated to the Qingbaikou system in the North China craton (NCC). • The northern Gyeonggi massif in the Korean Peninsula can be correlated to the NCC. [ABSTRACT FROM AUTHOR]

Background: The actual prescription pattern of immunosuppressive agents in kidney transplantation is unclear. Methods: We investigated the pattern and trend of immunosuppressive treatment for kidney transplant patients in South Korea. A total of 636 patients at nine transplant centers were enrolled and followed for one year. We reviewed medical records and evaluated induction therapy, as well as the changing pattern and cause of maintenance therapy. Results: Most patients (n = 621, 97.6%) received induction therapy often comprising basiliximab (n = 542, 85.2%). The triple therapy including calcineurin inhibitor, mycophenolic acid, and steroids was the major initial maintenance immunosuppression (n = 518, 81.4%), but its proportion decreased by 14% (81.4% to 67.5%) after 1 year. Almost 40% of patients changed immunosuppressive regimen during the 1-year follow-up, most often at an early period (60.2% within the first 4 months). The primary reason for the change was gastrointestinal discomfort (n = 113, 29.8%), followed by infection (112, 29.6%). The most common changing pattern was mycophenolic acid withdrawal (n = 155, 39.1%). Conclusion: The initial immunosuppressive regimen is prone to change within the first year of kidney transplantation. Further studies are needed to evaluate the benefits and risks in patients who changed immunosuppressants. [ABSTRACT FROM AUTHOR]

The spatial-temporal distribution of the Triassic post-collision-related and arc-related plutons in the Korean Peninsula is key to unraveling the positions of the Triassic collisional boundary and subduction zones in East Asia. Zircon U Pb dating of the Hajodae Granite, part of the granite-syenite-gabbro complex in the Yangyang area of the northeastern Gyeonggi Massif, gives a weighted mean 206Pb/238U age of 228.0 ± 2.3 Ma as the time of magmatism with a low zircon crystallization temperature of ∼770 °C. The Hajodae Granite and two-mica granites from the same complex belong to the shoshonitic to high-K and ferroan series and show high Rb/Sr and Rb/Ba ratios, suggesting melting of upper crustal materials and subsequent fractional crystallization. They plot in the post-collisional tectonic setting fields in trace element discrimination diagrams. Monzogabbros from the same complex are characterized by enrichment in LREEs and depletion in HREEs similar to those of OIB, with inherited subduction enrichments, suggesting their post-collisional tectonic setting. The southern limit of the post-collision-related Triassic plutons (∼235–225 Ma) in the Korean Peninsula marks a clear line defined as the Hongseong-Yangpyeong-Odesan (HYO) Belt within the Gyeonggi Massif, implying that the belt is the collisional boundary between the North China and South China Cratons. The Namhangjin Diorite in the southeastern Gyeonggi Massif yields weighted average zircon 206Pb/238U ages of 224.9 ± 2.0 Ma and 220.2 ± 2.1 Ma as the time of magmatism. They are characterized by low Y contents (9–12 ppm) and high Sr/Y ratios (91–135), indicating their adakitic nature. They are highly depleted in HREEs with convex-downward patterns between MREEs and HREEs in the C1 chondrite-normalized diagram, suggesting the presence of residual garnet and hornblende. They are characterized by high contents of compatible elements, including Cr (150–290 ppm), Ni (50–70 ppm), and MgO (3.47–5.24 wt%), have high Mg# of 60.4–63.4, and show higher zircon crystallization temperatures of ∼820–850 °C, suggesting that the Namhangjin Diorite was generated by the partial melting of delaminated lower crust due to extension related to slab roll-back of the subduction zone along the margin of northeastern Asia. Together with previous data, this study indicates that the Triassic igneous activity in the northern Gyeonggi Massif occurred in a post-collisional tectonic setting, whereas that in the southern Gyeonggi Massif, Ogcheon Belt, and Yeongnam Massif occurred in a subduction- or slab roll-back-related tectonic setting. [Display omitted] • Delaminated lower crustal adakitic rocks are confirmed from the Gyeonggi Massif. • Post-collisional plutons are present only north of the northern Gyeonggi Massif. • The collisional boundary of the North and South China Cratons in Korea is clarified. • Permo–Triassic subduction occurred along the eastern and southern margins of Korea. [ABSTRACT FROM AUTHOR]

Background: In Korea, cancer is the third leading cause of death among adolescents and young adults (AYAs). However, cancer incidence and survival trends among AYAs (15–29 years) have never been studied in Korea. Therefore, this study aimed to investigate the incidence and relative survival rates and their trends among AYAs in Korea. Materials and Methods: Cancer incidence data from 1999–2010 were obtained from the Korea Central Cancer Registry (KCCR). Each cancer was classified into subgroups according to the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) AYA site recode. Percent distributions, age-specific incidence rates, age-standardized incidence rates per million, and annual percent changes (APCs) were calculated for AYAs according to sex. Five-year relative survival rates were estimated for cases diagnosed between 1993 and 2010 and followed up to 2011. Results: The age-standardized incidence rates of all cancers combined were 196.4 and 367.8 per million for males and females, respectively (male-to-female (M/F) ratio: 0.5). The age-standardized incidence rates increased from 208.7 per million in 1999 to 396.4 per million in 2010, and the APC was 6.3% (P<0.001). The five most common cancers among AYAs were thyroid carcinoma, non-Hodgkin lymphoma, stomach carcinoma, breast carcinoma, and acute myeloid leukemia. In males, the 5-year relative survival rate improved, from 46.5% in 1993–1995 to 75.9% in 2006–2010. In females, the 5-year relative survival rate also improved, from 66.7% in 1993–1995 to 89.1% in 2006–2010. Conclusions: Our study showed increases in cancer incidence and improvements in the 5-year relative survival rate among Korean AYAs. This study also provides additional data regarding temporal and geographic trends in cancer that may enhance future efforts to identify factors affecting cancer incidence and responses to treatment among AYAs. [ABSTRACT FROM AUTHOR]

Objective: Our study aims to describe changes in carcinoma in situ (CIS) and invasive cervical carcinoma (ICC) in Korean women diagnosed between 1993 and 2009. Methods: All cases of CIS and invasive cervical carcinoma diagnosed from 1993 to 2009 in the Korean National Cancer Incidence database were analyzed. Age-standardized rates (ASRs) and annual percent changes (APCs) in incidence rates were compared according to age and histological type. Additionally, we used Korea National Health and Nutrition Examination Survey (KNHANES) to know the association between screening rate for cervical cancer and incidence rate of cervical cancer. Results: Between 1993 and 2009, 72,240 cases of ICC were reported in Korea. Total incidence rate of ICC was 14.7 per 100,000 females. ASRs of ICC declined 3.8% per year, from 19.3 per 100,000 in 1993 to 10.5 per 100,000 in 2009. Although the overall incidence rate of adenocarcinoma remained stable, invasive squamous cell carcinoma showed a decreasing trend (APC −4.2%). For women aged 60–79 years, ASRs for squamous cell carcinoma increased from 1993 to 2001, and decreased from 2001 to 2009 (APC: −4.6%). Total 62,300 cases of CIS were diagnosed from 1993 to 2009. Total incidence rate of CIS was 12.2 per 100,000 females. ASRs of CIS increased 5.7% per year, from 7.5 per 100,000 in 1993 to 19.0 per 100,000 in 2009. Adenocarcinoma in situ increased 13.2% per year. There was a strong positive correlation between screening rate for cervical cancer and incidence rate for CIS (p-value = 0.03) whereas screening rate showed a strong negative correlation with incidence rate for squamous ICC (p-value = 0.04). Conclusions: The increasing trend in CIS, coupled with a decreasing trend in ICC, suggests the important role of cervix cancer screening. The incidence of adenocarcinoma showed a plateau, but the incidence of adenocarcinoma in situ showed an increasing trend. [ABSTRACT FROM AUTHOR]

We analyzed the results of a multiphasic personal inventory test to confirm whether Moyamoya disease (MMD) affects the psychopathology in a group of young male Koreans. The authors manually reviewed the results of the Korean military multiphasic personal inventory (KMPI) for the examination of conscripts in Korea from July 2006 to May 2010. The normal volunteers group ( N = 200) was composed of those males who do not have any brain disease or brain trauma. The MMD group ( N = 37) was composed of those with MMD. There were more abnormal results in the MMD group (32.4 %) than in the normal volunteers group (13.0 %, p < 0.001). Results of the Neurosis Set showed that the anxiety scale, the depression scale and the somatization scale were more increased in the MMD group than that in the normal volunteer group ( p = 0.014, 0.002 and 0.006, respectively). Results of the Social Relation Set showed that the aggregation scale was more increased in the MMD group than that in the normal volunteers group ( p = 0.017). Young males with MMD may have more tendencies to have abnormal results of a multiphasic personal inventory test as compared to that of normal volunteers, suggesting that MMD may cause psychopathology in young Korean males. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, Clonorchis sinensis (C. sinensis) ancient DNA (aDNA) was successfully extracted from human remains discovered in a tomb dating to the medieval Joseon dynasty of Korea. The presence of C. sinensis eggs was confirmed by microscopic observation, after which a PCR-based aDNA analysis was performed using primer sets designed for the amplification of nuclear ribosomal internal transcribed spacer 1 (ITS1), 2 (ITS2) and mitochondrial cytochrome c oxidase 1 (CO1) genes. The sequences obtained were 100% homologous to some contemporary C. sinensis gene sequences reported from Korea and other East Asian countries. We believe that the results of our analysis expand the temporal and geographical scopes of research on the history of C. sinensis infection in different human populations. [Copyright &y& Elsevier]

Abstract: Of the parasite eggs discovered in ancient samples from Korean archaeological sites, Paragonimus spp. are of particular importance in that they are regarded as one of the most insidious trematode infection sources. Although their infection prevalence decreased rapidly in the early 20th century, archaeoparasitological studies on the species are still required, as historical knowledge of paragonimiasis remains far from comprehensive. Fortunately, we recently were given a chance to examine a medieval Korean mummy in a good state of preservation. Using morphological techniques, we discovered evidence of ectopic paragonimiasis in the sample from the 17th-century female. When the ITS 2 gene was extracted, amplified and sequenced from Paragonimus eggs, it showed 100% homology to the sequences of modern Paragonimus westermani reported from Korea and Japan, forming a cluster distinct from South Asian P. westermani. Our report is the first-ever analysis of ancient Paragonimus DNA from any archaeological field in the world. The ectopic paragonimiasis diagnosis made in this study, especially involving the liver sample, also is the first of its kind in archaeoparasitology. [Copyright &y& Elsevier]

Statural growth in human populations is a sensitive indicator of socio-economic well-being, and improvements in socio-economic status are reflected in secular increases in adult height. In the present study, we investigated the statures of historical Korean societies to show how stature changed over time. Applying Fujii's equation, derived from modern Japanese, to the measurement of femora removed from 15th- to 19th-century Joseon tombs, the average heights of Korean adults during the Joseon dynasty were estimated to be 161.1 ± 5.6 cm and 148.9 ± 4.6 cm for males and females, respectively. Plotting statures for successive historical societies against time revealed that Korean heights remained relatively unchanged through to the end of the 19th century, a pattern that differs from that seen in many Western countries in which stature transiently decreases after the Middle Ages. In contrast, a sharp increase in Korean stature was observed at the beginning of the 20th century, similar to trends seen in other nations (although exact timing varies in different countries). There were no accompanying changes of stature sexual dimorphism. The data reported in this study reflect the unique historical experience of Korea; the relative isolation of Joseon society, the late onset of modernization (at the end of the 19th century), and the later occurrence of industrialization (during the 1960s). Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Summary: In our previous CT and post-factum dissection studies on medieval Korean mummies, well preserved internal organs generally were found to have been displaced to the dorsal side of the body cavity. This movement seems to have been caused by the effect of gravitational force exerted over long burial durations. However, when we recently examined a newly discovered medieval Korean mummy (SN1-2) by CT, most of the mummified organs were found to have remained in their natural positions. Our post-factum dissection of SN1-2 showed that the organs might have undergone expansion by posthumous gas formation, after which they hardened into a stone-like state, which mitigated against their displacement. Similar CT findings were made in the case of a second Korean mummy (KU-1). Since the internal organs within the thoracic cavity were discovered to be in their natural positions, we suspected that they, like those in the case of SN1-2, had also been changed into stony structures. However, the post-factum dissection showed that the internal organs of KU-1 had neither hardened nor been displaced to the back wall of the thoracic cavity, owing possibly to the presence of a pleural adhesion. Overall, our results indicated that CT alone might be inadequate for correct estimation of the preservation status of internal organs in Korean mummies. This calls for further accumulation of dissection data, against which CT diagnoses can be compared and by which they can be improved. [ABSTRACT FROM AUTHOR]

Summary: Sex determination is very integral to examinations conducted by anatomists on human skeletons discovered in the archaeological field. In Korea, as in other countries, cultural or anatomical information has been the tool of first resort in making such determinations. In cases in which anatomical examination has revealed only borderline characteristics, PCR-based analysis of X/Y-chromosome genes has been employed. Even so, there are as yet very few reports on how accurately the respective results correspond with each other. In this study on 34 examined medieval Korean skeletons, 11 (32.3%) showed perfectly matching results for the three methods of sex determination. In the cases in which the cultural and anatomical findings were discordant, the amelogenin assay corroborated either the former or the latter. Although we must admit the relatively limited role of aDNA analysis, when only very small amounts of amplifiable DNA remain, we believe that the amelogenin assay can be very meaningful to Korean anatomists when employed in adjunct to conventional anatomically or culturally based sex determination. [ABSTRACT FROM AUTHOR]

Abstract: A paleo-parasitological study was performed on soil samples from archaeological sites in the old district of Seoul Metropolitan City (Old Seoul City) where the capital of the Joseon Kingdom was constructed about 600 years ago. The sampling sites were the original locations of the Royal Palace Wall, Yukjo Street and the Royal Arsenal. Microscopic examinations showed that parasite eggs of Clonorchis sinensis, Diphyllobothrium latum, Ascaris sp. and Trichuris sp. remained in the soil strata, which were estimated to represent the 14th-19th centuries. We suspect that the medieval citizens of Old Seoul City, numbering around 200,000, might have been made vulnerable to parasite infection by a combination of bad hygiene, inadequate sewer system and seasonal flooding. [Copyright &y& Elsevier]

Abstract: A new partial smoke extraction system for the Busan–Geoje immersed tunnel was investigated experimentally using simulated tunnel fires. The tests were performed in a 1:20-scale model tunnel with a smoke extraction duct between two traffic tubes. The fire corresponded to a 5-MW full-scale fire, based on Froude modeling. Isothermal and thermal experimental models were considered. The performance of the partial smoke extraction system was quantified under natural and longitudinal ventilation conditions. The results showed that the smoke extraction efficiency of the natural ventilation was 30% better than with longitudinal ventilation, because of smoke stratification in the tunnel. Additionally, the efficiency obtained from the thermal model was comparable to that from the isothermal model under both ventilation conditions. The results suggested that the use of a partial smoke extraction system without longitudinal ventilation improved the initial visibility during tunnel fires. [Copyright &y& Elsevier]

Abstract: Despite high prevalence of Trichuris trichiura infection, PCR-based analysis on T. trichiura from archaeological samples has not been established so far. In the present study, we sought to perform PCR-based amplification of T. trichiura aDNA using the sediments from medieval tomb of Korea. The presence of Trichuris eggs were first detected by microscopic observation; then confirmed by PCR-based aDNA analysis. Obtained sequence showed 100% homology to that of the small subunit ribosomal RNA (SSUrRNA) gene of T. trichiura but distinct from that of other Trichuris species. PCR-based aDNA analysis in this study can serve as effective method to confirm the presence of T. trichiura eggs in the soils or coprolites collected from archaeological sites. [Copyright &y& Elsevier]

Abstract: We conducted a paleo-parasitological study on soil samples from the ancient moat ruins of Weolseong palace, of the Silla Dynasty (BC 57–AD 935) of Korea. Based on the cultural remains found in the mud-soil layer, the layer was precipitated onto the floor of a moat between the 5th and 8th centuries AD. We found Trichuris trichiura eggs only in that mud-soil layer, whereas no parasite eggs were identified in the other archaeological strata of the ruins. As T. trichiura eggs are shed only in human feces, we speculated that palace toilet contents were continually drained into the moat; therefore, at a certain point in time after construction, the moat finally became a ditch around the palace. Structures in the stone embankments of the moat, possibly designed to make the water flow continuously in one direction, might reflect the Silla people''s efforts to alleviate the ever-increasing problems inherent in a moat. [Copyright &y& Elsevier]

The degree of organotin contamination was determined in samples of ten species of fish and shellfish that were representative of the Korean fish market. Shellfish and fish samples were collected in the fish markets of eight big cities in Korea (Gangneung, Ulsan, Pusan, Daegu, Guangju, Daejun, Incheon and Seoul). The edible portion of total 160 samples were analyzed for organotin compounds such as monobutltin (MBT), dibutyltin (DBT), tributyltin (TBT), monophenyltin (MPT), diphenyltin (DPT) and TPT (triphenyltin) by GC-MSD SIM mode after propylation and Florisil clean-up. Generally organotin levels of fish were higher than shellfish. The highest concentration of TBT was found in mackerel (average 67.02 ng/g-wet wt.) among fish and shellfish. TBT usually accounted higher percentage than that of MBT and DBT in most samples. However, the average concentration order of PTs in the tested samples was MPT > TPT > DPT except saury. [ABSTRACT FROM AUTHOR]

Kawasaki disease is a leading cause of acquired heart disease in children. The prevalence rate varies in different ethnic groups. Recently, with the clinical application of molecular genetic technology, human leukocyte antigen (HLA) polymorphisms associated with several diseases have been identified by DNA analysis. This study aimed to assess the association of HLA alleles with susceptibility and complications of Kawasaki disease in Korean children. In this study, DNA was extracted from 74 children with a diagnosis of Kawasaki disease. The polymorphisms of the HLA-A, -B, -C, and -DRB1 alleles of patients with Kawasaki disease were determined by polymerase chain reaction (PCR)–amplification refractory mutation system (ARMS) and PCR–sequence-specific primer (SSP) analysis. The polymorphisms identified were compared with those of 159 normal healthy control subjects. There was a significant increase in the frequencies of the HLA-B35, -B75, and -Cw09 alleles in patients with Kawasaki disease compared with the healthy control group. There was no increase in the frequency of HLA-DRB1 alleles among the Kawasaki disease patients compared with a healthy control group. When the patients with Kawasaki disease were divided into two subgroups, with or without coronary complications, the Kawasaki disease patients with coronary complications showed a significantly increased frequency of the HLA-DRB1*11 allele compared with the healthy control group and increased frequency of HLA-DRB1*09 in a comparison of the subgroups. This study suggests that polymorphisms in some alleles of B and C in HLA class I genes are associated with Kawasaki disease in Korean children. [ABSTRACT FROM AUTHOR]

In the Punggi area of the northeastern part of the Yeongnam Massif, one of Precambrian basement terrains in Korean Peninsular, the metamorphic grade increases from the amphibolite- to the granulite-facies zones towards the southeast. The boundary of the granulite-facies zone is defined by the orthopyroxene (Opx)-In reaction in metabasites. As metamorphic grade increases across the Opx-In isograd, the mineral assemblage in calcic metabasites is changed from clinopyroxene-amphibole-plagioclase to orthopyroxene-clinopyroxene-amphibole-plagioclase, and that in alkali metabasites from garnet-orthoamphibole-plagioclase to garnet-orthopyroxene-plagioclase. The metamorphic rocks in the granulite-facies zone were overprinted by upper amphibolite-facies retrograde metamorphism. During retrograde metamorphism, cordierite and spinel formed in the migmatitic gneiss. The P–T conditions of granulite-facies metamorphism are 767–815 °C and 6.0–8.4 kb and the P–T conditions for the retrograde stage are 595–707 °C/4.7–6.4 kb. A U–Pb zircon age of 1904±9 Ma has been obtained from a garnet granitic gneiss and is inferred to date the emplacement of its precursor. This is consistent with the intrusion age of precursors to most orthogneisses in other parts of the Yeongnam Massif. The same sample has yielded a Sm–Nd whole rock-garnet age of 617±38 Ma, which is inferred to represent a late Proterozoic metamorphic event of upper amphibolite facies. [Copyright &y& Elsevier]

To further understand the metamorphic evolution in the southern margin of the Jiao-Liao-Ji Belt in the Liaodong area, a detailed petrological and geochronological study was performed on representative metapelites from the South Liaohe Group. The peak metamorphic stage (M1) of the samples is represented by the mineral assemblage of garnet-biotite-plagioclase-sillimanite-quartz-magnetite in sample DD24-1 and garnet-biotite-plagioclase-ilmenite-quartz in sample DD24–2. The post-peak metamorphic stage (M2) is indicated by the appearance of cordierite with the mineral assemblage of biotite-cordierite-garnet-plagioclase-K feldspar-sillimanite-quartz-magnetite-ilmenite in sample DD24-1. The P-T calculations using pseudosections and conventional geothermobarometry imply that the M1, M2 and final retrograde stage (M3) metamorphisms occurred at 865–890 °C and 6.9–9.2 kbar, 840–860 °C and 5.3–6.2 kbar, and 570–670 °C and 3.3–4 kbar, respectively. The zircon SHRIMP U–Pb age data show that M1 metamorphism occurred 1867 ± 11 Ma and 1866 ± 8 Ma for samples DD24-1 and DD24–2, respectively. Together with previous studies, this study confirms that a low-P/T type granulite facies regional metamorphic event with a clockwise P-T path occurred in the South Liaohe and the Ji'an groups during 1.87–1.84 Ga. Together with the simultaneous postcollisional igneous activity in the South Liaohe and Ji'an groups, the low-P/T type metamorphism indicates that postcollisional activity occurred in the South Liaohe and Ji'an groups during 1.87–1.84 Ga due to slab break off after the collision. Combined with the prevailing postcollisional activity in the Nangrim Massif on the Korean Peninsula, this study suggests that the Longgang Block in the North China Craton subducted under the Nangrim Massif on the Korean Peninsula. • The southern margin of South Liaohe Group experienced low-P/T type metamorphism. • The low-P/T type metamorphism occurred at ~1.87 Ga with a clockwise P-T path. • The peak metamorphic conditions are 860–890 °C and 6.9–9.2 kbar. • The low-P/T type metamorphism occurred in the postcollisional tectonic setting. • The Longgang Block was subducted under the Nangrim Massif before collision. [ABSTRACT FROM AUTHOR]

Jangbong Island is located in the coastal area of the northwestern Gyeonggi Massif, and its basement is composed of Paleoproterozoic gneiss. The basement is covered by Neoproterozoic metasedimentary rocks such as pelitic schist, calc-schist, and quartz schist. These rocks are intruded by mafic dikes metamorphosed under amphibolite facies conditions. In the study area, two different metamorphic conditions are confirmed: the first was intermediate-P/T peak metamorphism (680-630 °C/8.6-7.3 kbar), and the second was low-P/T metamorphism (600-560 °C/5.7-3.1 kbar) showing a clockwise P-T path. All rocks in the studied area are intruded by Triassic gabbro and granite. Age measurement using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) yields intrusion ages of 917 ± 33 Ma and 873 ± 32 Ma for metabasites. Two different metamorphic ages are also obtained from them: 255 ± 12 ~ 254.3 ± 1.3 Ma and 231.5 ± 1.9 ~ 229.8 ± 1.4 Ma for the first and second metamorphic episodes, respectively. The Triassic gabbro yields an intrusion age of 229.1 ± 0.57 Ma and formed in a post-collisional tectonic setting with Triassic granite. The geochemical analysis confirms that Jangbong Island metabasites formed in a within-plate tectonic setting and are all alkaline basalts and mostly tholeiitic. The 917-873 Ma rift-related mafic intrusion is well matched with the Neoproterozoic rift-related mafic intrusions in the northern Gyeonggi Massif and along the southeastern margin of the North China Craton (NCC). The 255-254 Ma intermediate-P/T peak metamorphism is well matched with the collisional event in the northern Gyeonggi Massif, and the 231-230 Ma low-P/T metamorphism and 229 Ma post-collisional igneous activity are well correlated with post-collisional events in the northern Gyeonggi Massif. Together with previous data, these data support the correlation between the northern Gyeonggi Massif and the NCC. • Mafic dykes intruded at 917-873 Ma in the within-plate tectonic setting • Intermediate-P/T peak metamorphism during the Permo-Triassic collision (255-254 Ma) • Low-P/T metamorphism with intrusion of post-collisional igneous rocks (231-230 Ma) • Mafic dykes in the NGM can be correlated with those in the southeastern margin of NCC [ABSTRACT FROM AUTHOR]

Jurassic dioritic to granitic igneous rocks extensively intrude into the southern Korean Peninsula, including the Yuseong area located at the boundary between the southern margin of the Gyeonggi Massif and the northern margin of the Okcheon Belt. In this study, the petrogenesis and sources of Jurassic igneous rocks in the Yuseong area were investigated. The U–Pb zircon age data from the Jurassic plutonic rocks in the Yuseong area give two igneous ages, ca. 178–177 Ma and 169–168 Ma, indicating that two stages of igneous activity occurred in the Yuseong area during the Jurassic. The geochemical characteristics of Jurassic diorites indicate that they originated from enriched mid-ocean ridge basalt (E-MORB; Nb/Yb = 5.63–7.27; Zr/Yb = 118–156). The enriched Th/Yb ratios (5.5–8.0) in the diorites imply that they experienced crustal contamination during magma ascent. The Jurassic granitoids in the Yuseong area are divided into I- and S-type granites. The Jurassic I-type granitoids may have formed via the partial melting of mafic rocks with mixtures of 10–40% pelite-derived melt, while the S-type granites originated from felsic pelite. The Jurassic diorites have low Nb/Th ratios with depletion of the Nb and Ta components, indicating that they formed in a volcanic arc tectonic environment. On the other hand, the Jurassic granitoids show two different tectonic environments: a volcanic arc, and a syncollisional environment. The granites with syncollisional character are S-type granites, and may give incorrect information about tectonic setting because of the changes in the trace elements of the S-type granite due to fractional crystallization. Early Jurassic (200–190 Ma) igneous rocks are distributed only in the southeastern Korean Peninsula, including the Yeongnam Massif; Jurassic igneous rocks formed at ca. 190–180 Ma occur mainly in the Okcheon Belt and southern Gyeonggi Massif, which includes the Yuseong area. Middle Jurassic igneous rocks widely intruded from the Okcheon Belt, through the Gyeonggi and Nangrim massifs in the Korean Peninsula, to the Liaoning area in the North China Craton at 180–160 Ma. This distribution pattern of the Jurassic granitoids suggests that flat subduction started after 180 Ma in Northeast Asia. [ABSTRACT FROM AUTHOR]

The Neoproterozoic rocks recognized in several locations on the Korean Peninsula provide important insight into the geological correlation between the Korean Peninsula and China and for understanding the tectonic processes occurring in northeastern Asia. The Gogunsan Islands, located on the southwestern margin of the Gyeonggi Massif of the Korean Peninsula, consist of Neoproterozoic igneous and sedimentary rocks. The sedimentary rocks in the Gogunsan Islands are divided into the Maldo and Bangchukdo Formations. The Maldo Formation was deposited sometime between 950 and 894 Ma and intruded by or tectonically contacted Neoproterozoic igneous rocks 930–894 Ma in an arc tectonic setting. The εHf (t) values of metabasites (3.63 to −5.09) and metagranitoids (3.29 to −5.76) indicate that the metabasites were formed from 1.67–1.32 Ga depleted mantle and the metagranitoids were formed by the reworking of ancient crust, which formed from 2.14–1.57 Ga depleted mantle. The metabasites in the Maldo Formation underwent intermediate-P/T amphibolite-facies metamorphism (4.35 ± 1.15 kbar and 465 ± 15 °C) with strong deformation before the deposition of the Bangchukdo Formation, indicating a collision event. The Bangchukdo Formation was deposited after 792–763 Ma in the rifting tectonic setting. The data in this and previous studies suggest that the Neoproterozoic igneous rocks in the Gogunsan Islands can be correlated to arc-related Neoproterozoic rocks formed during the Jiangnan orogeny on the southern margin of the Yangtze Block in the South China Craton. Along the Jiangnan orogenic belt, the arc stage was followed by the collision between the Yangtze and Cathaysia Blocks. The collision may have started in the Korean Peninsula and propagated westwards into South China. • Gogunsan Islands(GI) located in southwestern Gyeonggi Massif in Korean Peninsula. • The Maldo Formation(MF) in GI underwent intermediate-P/T metamorphism. • Neoproterozoic igneous rocks intruded the MF at 930-894 Ma in arc tectonic setting. • The Bangchukdo Formation was deposited after 792–763 Ma in rifting tectonic setting. • GI can be correlated with the Jiangnan orogenic belt in the South China Craton. [ABSTRACT FROM AUTHOR]

The Neoproterozoic igneous rocks in the northern and southern Gyeonggi Massifs in the southern Korean Peninsula are important for the interpretation of the Neoproterozoic tectonic evolution of the Korean Peninsula and northeastern Asia. The Gonamsan and Chuncheon metabasites in the northern Gyeonggi Massif intruded in a within-plate tectonic setting at ca. 851–873 Ma and 888 Ma, respectively. The Nb/Yb ratios (7–23) of these metabasites represent enriched mid-ocean ridge basalt (E-MORB) to ocean island basalt (OIB) characteristics. Most zircons found within the Gonamsan metabasites have positive ε Hf (t) values and Paleoproterozoic to Mesoproterozoic isotopic model ages (T DM2). These metabasites have initial 87Sr/86Sr ratios that range between 0.7033 and 0.7058 and ε Nd (t) values of −0.68 to 5.02. These geochemical characteristics of these metabasites indicate that these rocks formed in a rift-related environment. The Neoproterozoic metabasites from the Dangjin area in the southwestern Gyeonggi Massif can be subdivided into arc and rift types. The Dangjin arc-type metabasites intruded at ca. 820–833 Ma. These metabasites have Nb/Yb ratios of 4–7, Nb/U ratios of 3.58–27.5 and show an increase in Th/Nb ratios with increasing La/Sm ratios. Most zircons from these metabasites have negative ε Hf (t) values and Paleoproterozoic-Archean T DM2 ages, except one that has positive ε Hf (t) values and a Mesoproterozoic T DM2 age. Most these metabasites have initial 87Sr/86Sr ratios of 0.7048–0.7105 and negative ε Nd (t) values from −11.67 to −5.25. These geochemical characteristics indicate that the arc type Dangjin metabasites experienced crustal contamination during differentiation in an arc tectonic environment. The rift-related Dangjin metabasites intruded at ca. 793 Ma in a similar manner to the Gonamsan and Chuncheon metabasites. The Nb/Yb ratios (8–11) of these metabasites are higher than those of the arc-type metabasites. These metabasites have lower initial 87Sr/86Sr ratios of 0.704 and higher ε Nd (t) values of 1.96 than the Dangjin arc-type metabasites. Together with the results of previous work, this study indicates that the tectonic setting of the Dangjin-Hongseong area was an arc during the period 820–900 Ma and then changed into a rift during the period 703–793 Ma. The Neoproterozoic igneous rocks in the northern Gyeonggi Massif can be correlated with those formed in the within-plate tectonic setting in the southern and southeastern margins of the North China Craton during the period 830–930 Ma. On the other hand, the Neoproterozoic igneous rocks in the southwestern Gyeonggi Massif can be correlated to the Neoproterozoic arc- and rift-related igneous rocks in the northern margin of South China Craton, which intruded during 850–871 and 637–820 Ma, respectively. Unlabelled Image • Rift related events occurred in the northern Gyeonggi Massif (NGM) at 742–888 Ma • The arc-related igneous rocks intruded the southwestern GM (SGM) during 820–900 Ma • The SGM was intruded by rift-related igneous rocks at 703–793 Ma • The Neoproterozoic rocks in the NGM can be correlated with the North China Craton • The Neoproterozoic rocks in the SGM can be correlated with the South China Craton [ABSTRACT FROM AUTHOR]

• Jinan area experienced granulite facies metamorphism at ~8.5–7 kbar and 800-760 ℃. • The peak metamorphism occurred at1.87–1.84 Ga along with a clockwise P-T path. • Porphyritic granitoids intruded at 1.87–1.84 Ga in a post collisional tectonic setting. • The post collisional igneous and metamorphic activities occurred simultaneously after collision. • This study suggests the existence of subduction before collision in the JLJB. The Jiao-Liao-Ji Belt (JLJB) is a Paleoproterozoic collisional belt between the Longgang Block in the northeastern North China Craton and the Nangrim Massif on the Korean Peninsula. The Jinan area, located in the northeastern JLJB, was intruded by monzogranite at 2151 ± 6 Ma and then intruded again by porphyritic granites at 1842 ± 5 Ma in a postcollisional tectonic setting. The monzogranite and an associated gabbro were metamorphosed into metamonzogranite and metabasite at 1868 ± 11 Ma–1846 ± 3 Ma. Pelitic granulites occur together with the porphyritic granites. The pelitic granulites have peak metamorphic mineral assemblages of garnet + biotite + plagioclase + K-feldspar + sillimanite + quartz + ilmenite and underwent retrograde metamorphism, as evidenced by the presence of cordierite and muscovite. Pseudosection analysis of the granulites yields peak metamorphic conditions of ~8.5–7 kbar and 800–760 °C, and conventional geothermobarometry analysis of garnet rims and adjacent minerals yields retrograde metamorphic conditions of ~5–3.5 kbar and 740–680 °C. Dating of monazite from the two granulites demonstrates that peak metamorphism occurred between 1840 ± 2 Ma and 1847 ± 4 Ma. These results, together with the findings of previous studies, indicate that in the Liaodong and Jinan areas of the JLJB, igneous and metamorphic activities occurred together at ~1.85 Ga in a postcollisional tectonic setting, suggesting that collision between the Longgang Block and the Nangrim Massif occurred before ~1.85 Ga. [ABSTRACT FROM AUTHOR]

Most of the mid to late Cretaceous igneous rocks in the southeastern margin of the Northeast Asian continent are interpreted to be formed due to upwelling of asthenospheric mantle caused by slab rollback and associated back-arc extension. However, the tectonic environments for the mid-Cretaceous igneous rocks in the Korean Peninsula is uncertain. The Jinan Basin is one of the Cretaceous pull-part basins in the southern Korean Peninsula. The mid-Cretaceous volcanic rocks occur in association with the Jinan Basin. In this study, we investigated whole-rock major and trace element geochemistry and Sr-Nd-Pb isotope compositions of the mid-Cretaceous volcanic rocks in the Jinan Basin to understand their petrogenesis and tectonic environments. Also, U-Pb zircon age of sedimentary and volcanic rocks in the Jinan Basin was determined to constrain the age of sedimentation and igneous activities. The results show that sedimentation started at least from 97.7 Ma and continued until 89.5 Ma. The sedimentary sequences were intermittently extruded by rhyolitic and andesitic magma 90–89 Ma, and later intruded by basaltic trachyandesite 84 Ma. The volcanic rocks in the Jinan Basin show geochemical features of alkaline to high-K calc-alkaline magma series with strong enrichment in large ion lithophile elements and light rare earth elements relative to high field strength elements. The mafic and intermediate volcanic rocks are distinguished from the typical continental arc magmas by enrichment in incompatible elements such as Y and Zr with high Zr/Y, suggesting that they originated from an enriched source. The basaltic trachyandesites and andesite have Sr isotope ratios (87Sr/86Sr i) of 0.708769–0.709484 and Nd isotope ratios (143Nd/144Nd i) of 0.511782–0.511886, which indicate that they formed from mantle which was contaminated with crustal component in their petrogenesis. The Pb isotope data (206Pb/204Pb = 17.572–18.158, 207Pb/204Pb = 15.535–15.640 and 208Pb/204Pb = 38.366–38.921) suggest that the crustal component should have experienced a prolonged evolution with a low μ value. The Mg# (46–57) and Cr contents (40–180 ppm) in the mafic to intermediate rocks higher than typical crustal melts at a given range of SiO 2 , showing that they evolved from a mantle-derived primary magma. We attribute the crust-like geochemical and isotopic signature of the Jinan mafic and intermediate igneous rocks to the partial melting of enriched lithospheric mantle metasomatized by subduction components and subsequent crustal assimilation during magma ascent and pooling at the mid-crustal depth of ~9–10 km. The geochemical and isotopic features of the Jinan volcanic rocks are similar to those of the mid-Cretaceous basaltic volcanic rocks in the Yeongdong and Gyeongsang Basins, South Korea and the southeastern margin of South China Craton (SCC). This may suggest that the partial melting of the enriched lithospheric mantle, induced by slab rollback of the paleo-Pacific plate and upwelling of the asthenospheric mantle, was widespread underneath the southeastern Korean Peninsular as well as the southeastern margin of SCC. • The Jinan Basin locates in the southern Korean Peninsula (SKP). • Volcanic activity in the Jinan Basin occurred during mid-Cretaceous (mid-C). • Mid-C igneous activities in SKP formed due to back-arc extension. • The extension caused asthenospheric mantle upwelling supplying heat. • Mid-C volcanic rocks in SKP formed by partial melting of enriched SCLM. [ABSTRACT FROM AUTHOR]

• Arc metamorphism in the northcentral Yeongnam Massif at ca. 1.87–1.86 Ga. • Arc magmatism in the northcentral Yeongnam Massif at ca. 1.87–1.69 Ga. • The arc events are linked to that in the northeastern Yeongnam Massif. • The Yeongnam Massif does not correlate with the North China Craton. The Paleoproterozoic basement of the Korean Peninsula consists of three massifs, the Nangrim, Gyeonggi and Yeongnam Massifs, from north to south. In the Muju area of the northcentral Yeongnam Massif, amphibolites intruded the Paleoproterozoic metasedimentary rocks and orthogneisses. The amphibolites can be divided into Type-I and Type-II amphibolites. The whole-rock geochemical data and zircon Lu–Hf composition of the amphibolites suggest that the Type-I and Type-II amphibolites formed in an island and continental arc tectonic setting, respectively, and both amphibolites were derived from enriched mantle sources. Zircon U–Pb dating reveals that the Type-I and Type-II amphibolites were emplaced at ca. 1.87 Ga and 1.69 Ga, respectively. The surrounding metasedimentary rock (migmatite) underwent upper amphibolite facies (720–730 °C and 7.3–7.4 kbar) metamorphism and then underwent amphibolite facies retrograde metamorphism (520–622 °C and 1.7–3.5 kbar). The zircon U–Pb dating reveals that the peak metamorphism occurred at ca. 1.87–1.86 Ga. The geothermal gradient (approximately 32 °C/km) during peak metamorphism correlates with that of the arc area, indicating that metamorphism occurred in an arc tectonic setting. These data suggest that the northcentral Yeongnam Massif underwent arc-related magmatic and metamorphic events during ca. 1.87–1.69 Ga. This finding indicates that the northcentral Yeongnam Massif does not correlate well with the Nangrim and northern Gyeonggi Massifs, which are correlated with the eastern North China Craton, because the Nangrim and Gyeonggi Massifs underwent postcollisional igneous activity during ca. 1.88–1.84 Ga. [ABSTRACT FROM AUTHOR]

Abstract: The tectonic relationship between Korea, China and Japan has been a topic of debate since several decades. Several recent studies have brought to light new aspects of Korean geology including the finding of Late Permian to Triassic eclogite facies metamorphism from the Hongseong area. There has also been substantial progress on the understanding of the tectonic history of East China. New reports of Paleozoic and Triassic high-P/T metamorphic belts have also come from Japan. This thematic issue of Gondwana Research presents a timely integration of new information that aids in reconstructing the tectonic relationship between Korea, China and Japan. This issue begins with a set of four papers dealing with the tectonic relationship between Korea, China and Japan. The next five papers deal with various aspects of Korean geology from Late Proterozoic to Cenozoic. Subsequent five papers are related to the geology of Japan. The next three papers deal with the tectonic interpretation of the Sino-Korean plate. Evidence for Permo-Triassic collision between the Indo-china and South China blocks is reported in the next paper. We thank reviewers for providing thorough and constructive reviews on the manuscripts for this issue. We also thank the International Association for Gondwana Research for providing us the opportunity to publish this thematic issue. [Copyright &y& Elsevier]

Abstract: CALPHAD XXXIX (May 23–28, 2010) was held in Jeju, Korea, organized by Byeong-Joo Lee, Chang-Seok Oh, Joonho Lee, Jae-Hyeok Shim and Hyuck Mo Lee. 125 registered participants presented 73 oral contributions and 52 posters, including 5 invited talks by experimental researchers from various materials research fields in a specially inserted session named “experiments that need thermodynamic analysis”. Poster sessions were held on the evening of Monday and Tuesday. A “Young Calphadian Meeting” was also organized on Tuesday evening after the poster session with A. Pelton, B. Sundman and J. Ågren as invited speakers. There was a conference excursion to the Jeju forkvillage during Wednesday afternoon. The Best Paper Award for papers published in 2009 in the CALPHAD journal and a Best Poster Award for one of the conference’s posters were conferred during the conference dinner on Wednesday evening. The abstracts and titles of oral presentations and titles of poster presentations are summarized in this report. [Copyright &y& Elsevier]

The chemical behavior of major inorganic ions in the streams of the Mankyung River area (South Korea) was investigated. Mixing with effluent from the Jeonju STP (a municipal sewage treatment plant in Jeonju City) was the most important process in regulating the water chemistry of the streams. The effluent was chemically distinct relative to the stream waters in inorganic composition. Behavior of various ions was evaluated by comparing their concentrations with the concentration of chloride, a conservative chemical species. It was revealed that concentrations of chloride and sulfate, the total concentration of major cations, and electrical conductivity in the stream were controlled only by mixing, indicating their conservative behavior similar to chloride. Alkalinity and concentration of nitrate, however, were regulated by various reactions such as mixing, photosynthesis, respiration, and decomposition of organic matter. Streamflows were estimated by observing chemical composition of the effluent and those of up/downstream waters. Estimated flows based on the conservative chemical parameters were nearly the same as those directly measured using an area–velocity method, indicating the validity of the chemistry-based method. [Copyright &y& Elsevier]

• Arc magmatism occurred along the northern Yeongnam Massif at ca. 2.02–1.96 Ga. • Paleoproterozoic igneous rocks were metamorphosed ca. 1.89–1.87 Ga. • Crustal growth and reworking events occurred at ca. 3.25 Ga and 2.02 Ga, respectively. • Yeongnam Massif underwent different tectonothermal event compared to the North China Craton. The Jangsu-Gokseong area is located in the southwestern part of the Yeongnam Massif and mainly consists of Precambrian metagranitoids (metagranite, metaleucogranite and metagranodiorite) with minor migmatite and marble. Sensitive high-resolution ion microprobe (SHRIMP) zircon U–Pb dating shows that the metagranitoids emplaced during ca. 2.02–1.96 Ga and metamorphosed at ca. 1.89–1.87 Ga. The metagranitoids show calc-alkaline trends, enrichment in large lithophile elements and negative Nb and Ta anomalies with low Sr/Y (<12), Nb/Th (<1) and Nb/Zr (<0.1) ratios. The metagranitoids have negative ε Hf (t) values (−1.63 to −6.41) with a Paleoarchean two-stage model age (T DM2 = 3.25 Ga). These data suggest that the protoliths of the metagranitoids were derived from ancient crustal materials with metagraywacke or metatonalitic compositions and formed in a subduction-related setting. The intrusion ages and geochemical composition of the metagranitoids in the study area match well with those of Paleoproterozoic metagranitoids distributed along the northern margin of the central to northeastern Yeongnam Massif. These metagranitoids show that Paleoproterozoic (ca. 2.02–1.96 Ga) subduction-related magmatism occurred widely along the northern margin of the Yeongnam Massif, which has not been reported from the Gyeonggi and Nangrim massifs on the Korean Peninsula and the Jiao-Liao-Ji belt in the eastern North China Craton. Therefore, the Yeongnam Massif might have existed as a separate crustal unit at least during the Paleoproterozoic. [ABSTRACT FROM AUTHOR]

Background: Previous studies showed that the insulin resistance (IR) could be related to depression. However, this association is still equivocal in the general population. Herein, we aimed to investigate the association between IR and depressive symptoms in a large sample in South Korea.Methods: A cross-sectional study was carried out for 165,443 Korean men and women who received a health checkup including various clinical parameters and the Center for Epidemiologic Studies Depression scales (CES-D). Subjects were stratified into subgroups by CES-D score, sex, age, and presence of diabetes. The odd ratios (ORs) for homeostasis model assessment of insulin resistance (HOMA-IR) were compared between groups using multivariable logistic regression analyses.Results: After adjusting covariates (e.g. smoking, family income, marriage state, unemployment status, average alcohol use, BMI, physical activity, systolic blood pressure, diabetes), increased IR was weakly associated with greater depressive symptoms (adjusted OR=1.01 [95% CI 1.0001-1.03]). Subgroup analysis revealed this association was statistically significant in females (adjusted OR=1.03, [95% CI 1.001-1.06]), non-diabetic group (adjusted OR=1.04, [95% CI 1.02-1.06]), and young participants under the age of thirty (adjusted OR=1.17, [95% CI 1.07-1.27]). But we couldn't find significant association in diabetic and middle to elderly participants.Conclusions: This study demonstrates that there is a relationship between IR and depressive symptoms in the Korean general population. Results from this epidemiological study revealed that young adults and non-diabetic individuals with increased IR may be related with depressive symptoms. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Prevalence and distribution of dental caries in medieval Korean society were evaluated. Materials and methods: Two thousand and nine hundred teeth samples of 126 individuals collected from 16th to 18th century Korean tombs. Results: Preservation status of sample was good. The prevalence of ante- and postmortem tooth loss was 4.4% and 14.2%, respectively. The total caries prevalence was 3.9%. The tooth surface most frequently affected by dental caries was occlusal (4.5%), followed by approximal (2.1%), buccal (1.5%), and lingual (1.1%) surfaces. Discussion: The prevalence of dental caries in Joseon Dynasty skeleton collection was lower than have been found in other collections of similar chronology. The low consumption of refined sugar in medieval Korean society might be a possible explanation, though the technical limitations inherent in such comparison studies preclude definitive conclusions. [Copyright &y& Elsevier]

Abstract: Background: Endoglin is a component of the transforming growth factor-β receptor complex and is predominantly expressed on the cell surface of endothelial cells. It plays an important role in vascular growth and development. There have been conflicting reports on whether a polymorphic variant, in the endoglin gene, is associated with risk for IAs. In this study, we investigated whether polymorphisms of the endoglin gene are associated with the development of cerebral aneurysms in a Korean population. Methods: This was a hospital-based, case-control study conducted at the Chonnam University Hospital, Gwangju, Korea. The study population consisted of 342 patients who had been treated for intracranial aneurysm and 253 healthy, hospital-based controls. Two polymorphic loci were amplified by polymerase chain reaction. The well-known in/del in intron 7 of the endoglin gene and the rs1800956 coding nonsynonymous SNP were amplified by PCR and analyzed by MADGE or the pyrosequencing system. Results: The endoglin insertion polymorphism was not associated with IAs in comparisons between cases and controls (OR, 0.11 [95% CI, 0.79-1.57] vs OR, 0.88 [95% CI, 0.50-1.56]). An association was found with rs1800956 in the heterozygous type (OR, 1.71); however, the association was not evident for the homozygous type. These differences were statistically significant. In addition, the C allele was significantly associated with an increased risk for IAs (OR, 1.73). Conclusion: The rs1800956 (G/C transversion with D366H substitution, National Center for Biotechnology Information SNP database) of endoglin may play an important role in the pathogenesis of IAs in the Korean population. However, the in/del of intron 7 was not associated with an increased risk for IAs, which is consistent with the findings of previous reports. [Copyright &y& Elsevier]

• The granitoids are of higher in potassium than sodium. • SIMS zircon dating gives Neoarchean-early Paleoproterozoic protoliths ages (2.45–2.56 Ga). • Multiple metamorphic events at ~2.50 Ga, 1.8–1.9 Ga, ~160 Ma were identified. • The magmatism corresponds to incorporating juvenile crustal components and reworking of older Archean crust. • The Archean – Paleoproterozoic multiple magmatism and metamorphism of the RM are similar with eastern NCC. The geology of the Korean Peninsula's northern part is little known to the international community. Even though this area is a critical link between various eastern Asia terranes, its tectonic architecture and geochronological framework are still gaps in knowledge. This study reports integrated field, geochemical and geochronological characteristics of the Precambrian gneissic rocks from this region, focusing on the Rangnim Massif. The studied samples are divisible into three groups according to their field occurrence as granitic gneiss, fine-grained biotite gneiss and leuco-veins. The essential mineralogy of all these rocks is biotite (Bt), muscovite (Mu), plagioclase (Pl), K-feldspar (Kf) and quartz. The analyzed samples show high SiO 2 (65.92–77.63 wt%) and Al 2 O 3 (10.23 to 17.56 wt%) contents, low MgO and CaO. Their K 2 O contents is mostly higher than Na 2 O. SIMS (Secondary Ion Mass Spectrometry) zircon U-Pb dating of the eleven samples yields magmatic protolith ages of 2454–2567 Ma and multiple metamorphic overprintings during the earliest Paleoproterozoic (~2.45 Ga), Paleoproterozoic (1.87–1.93 Ga) and Jurassic (160 Ma). The presence of these potassic granitoids in different locations indicate the high extent maturation of Neoarchean continental crust in the Rangnim Massif. Zircon Lu-Hf isotopic results of these samples show large variations, mostly plotting between the Depleted mantle linear model line and Chondritic Uniform Reservoir (CHUR) line, but some have negative ε Hf (t) values. Considering that their protoliths are all crust melting products, it can be concluded that the Neoarchean magmatism incorporated both juvenile crustal components as well as a reworking of older crust. This is supported by the detection of rare early Archean xenocrysts. Based on Juvenile crust having ε Hf values of ~0 before 3500–3600 Ma, it is concluded that the reworked components were Eoarchean in age, not Hadean. Magmatic as well as Precambrian metamorphic pulses of the Rangnim Massif show broad similarities with the eastern North China Craton, Gyeonggi and Yeongnam Massifs and southwest Japan, which seem to suggest that they might share a coherent Precambrian basement and evolutionary history, at least before the end of late Paleoproterozoic. [ABSTRACT FROM AUTHOR]

Metagonimiasis is foodborne intestinal parasitism occurring by the definitive hosts' ingestion of raw or undercooked fish, mostly commonly sweetfish. Most Metagonimus infection is caused by Metagonimus yokogawai but also rarely by Metagonimus takahashii as well as Metagonimus miyatai. Despite recent molecular work on Metagonimus spp., there are still insufficient data to reveal the genetic characteristics of ancient M. yokogawai in a wide geo-historical scope. In this study, we were successful in the analysis of M. yokogawai ancient DNA (aDNA) using coprolite samples retrieved from 16th- to 17th-century Korean mummies. In BLAST and phylogenetic analyses, M. yokogawai 28S rDNA of Korean mummies were clustered along with the 28S rDNA taxa of M. takahashii and M. miyatai in GenBank. Conversely, the cytochrome c oxidase subunit I (COI) of M. yokogawai aDNA from Korean mummies was distinctly clustered apart from M. takahashii and M. miyatai sequences. This study is the first report of its kind to identify M. yokogawai aDNA retrieved from the archaeological specimens and confirms the usefulness of COI in molecular diagnosis of M. yokogawai. Considering the rarity of reports on the genetics of genus Metagonimus spp., our study will be fundamental for the future study of M. yokogawai paleogenetics., (© American Society of Parasitologists 2020.)

Although parasitic infection by Trichuris trichiura is a very common intestinal helminthic disease worldwide, there is still insufficient information on the genetic characteristics of ancient T. trichiura in different spatiotemporal perspectives. Utilizing coprolite specimens obtained from 15th-18th century mummies dating to the Joseon Dynasty, we analyzed small-subunit ribosomal RNA, internal transcribed spacer 2, and ATP synthase subunit 8 of T. trichiura ancient DNA (aDNA). In BLAST and phylogenetic analyses, the T. trichiura aDNA sequences of this study belong to a separate cluster that is evidently distinct from the other genus Trichuris spp. reported in GenBank. This report characterizes T. trichiura aDNA of pre-20th century East Asia, and in so doing, it also proves the potential of aDNA analysis for differential diagnosis of T. trichiura in cases where ancient parasite eggs are morphologically indeterminate for species identification.

Background: Elevated blood pressure (BP) is a component of the metabolic syndrome (MetS), and one third of individuals with hypertension simultaneously have MetS. However, the evidence is still unclear regarding the predictive ability of BP for incident MetS., Methods: In total, 5,809 Koreans without baseline MetS were grouped by baseline systolic (SBP) and diastolic BP (DBP) and monitored for 10 years to identify incident MetS. A Cox proportional hazards model was used to evaluate the HR and 95% CI for MetS according to SBP and DBP. Subgroup analysis was conducted in the normotensive population based on a new guideline of the American College of Cardiology and the American Heart Association., Results: High-BP groups tended to have worse metabolic profiles than the lowest-BP group in both SBP and DBP categories. In all of the participants, elevated SBP and DBP levels were significantly associated with the increased HR for MetS, even after adjusting for covariates. Subgroup analysis for normotensive participants indicated that the HR for MetS increased proportionally to both SBP (<110 mm Hg: reference, 110-119 mm Hg: HR = 1.60 [95% CI 1.40-1.84], and 120-129 mm Hg: HR = 2.12 [95% CI 1.82-2.48]) and DBP levels (<70 mm Hg: reference, 71-74 mm Hg: HR = 1.31 [95% CI 1.09-1.58], and 75-79 mm Hg: HR = 1.51 [95% CI 1.25-1.81])., Conclusion: The risk of incident MetS increased proportionally to baseline SBP and DBP, and this was identically observed even in normotensive participants., (© 2019 S. Karger AG, Basel.)

Background: Although impaired glucose tolerance (IGT) is a definite risk factor for type 2 diabetes mellitus (T2DM), there is limited information about the risk stratification for incident T2DM within IGT group. Thus, we aimed to evaluate the incidental risk for T2DM according to 2-h plasma glucose (2-h PG) level of oral glucose tolerance test (OGTT) and phenotype of IGT., Methods: 7654 Korean participated in the Korean Genome and Epidemiology Study (KoGES) were stratified by 2-h PG levels of OGTT, and followed up for 63,665 person-years. Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidential interval (CI) for T2DM according to 2-h PG levels of OGTT with adjustment for multiple covariates. Subgroup analysis was performed by gender and the presence of impaired fasting glucose (IFG) or not., Results: Within IGT, the adjusted HRs for T2DM significantly increased proportionally to 2-h PG level [<140mg/dL: reference, 140-159mg/dL: 3.07 (2.67-3.54), 160-179mg/dL: 5.44 (CI 4.66-6.34), 180-199mg/dL: 7.91 (CI 6.53-9.59)]. IGT combined with IFG had the profoundly increased HRs than isolated IFG. Even within normal glucose tolerance (NGT), 2-h PG level≥120mg/dL had the higher risk for T2DM than other NGT groups. These associations were more dominant in male than female., Conclusion: The highest level of 2h-PG (180-199mg/dL) in IGT and IGT with IFG were strong predictor for T2DM. 2-h PG of 120-139mg/dL was more significantly associated with T2DM within NGT, and male was more susceptible for T2DM than female., (Copyright © 2017. Published by Elsevier B.V.)

We analyzed Ascaris ancient DNA of cytochrome b, cytochrome c oxidase subunit 1, NADH dehydrogenase subunit 1, and internal transcribed spacer 1 genes extracted from the feces or precipitates of 15- to 18th-century Korean mummies. After multiple Ascaris genes in ancient samples were successfully amplified by polymerase chain reaction (PCR), consensus sequences could be determined by the alignment of the sequences of cloned PCR products. The obtained sequences of each gene were highly similar to those of Ascaris spp. reported thus far but were genetically distinct from Baylisascaris, Parascaris, and Toxascaris spp. The current report establishes that the genetic characteristics of the Ascaris spp. infecting pre-modern Korean societies were not uniform but were diverse to some degree.

In the coprolites of 4 recently discovered Joseon mummies of Korea, we found Ascaris lumbricoides , Trichuris trichiura , Metagonimus yokogawai , Paragonimus westermani , and Clonorchis sinensis eggs. The current finding was compared with previous paleoparasitological data, and with recent national survey data from Korea. For A. lumbricoides and T. trichiura , similar patterns of infection prevalence were observed between the national survey of 1961 and our current Joseon data. Some of the trematode species (C. sinenesis and P. westermani) showed much higher infection prevalences among the Joseon Koreans than among their 1960s descendants. The present results indicate that the decrease in trematode infection rates might have begun earlier than was the case for nematode infection.

Gymnophalloides seoi is a trematode species discovered as recently as 1993. Interestingly, ancient G. seoi eggs were identified in our earlier study on a 17th Century female mummy unearthed in a Korean county (HD-1) where G. seoi infection, according to a nationwide survey of 2001, was considered not to have been endemic. Although we suspected that the geographical distribution of G. seoi might have contracted over the past several hundred years from wider coastal areas on the Korean peninsula to the much more restricted region delineated by the survey, there has been only the single, above-noted report of an ancient G. seoi infection in a currently non-endemic area. As such, more evidence is needed before our contraction theory of G. seoi infection prevalence can be confirmed as fact. Our current report in this regard will perhaps help to end the controversy. In a newly discovered 17th Century male mummy found in another Korean county considered non-endemic by the 2001 survey, we identified a large number of ancient G. seoi eggs. We believe that this additional evidence for a wider distribution of G. seoi infection prior to the 20th Century is invaluable support for our earlier hypothesis.

Unlabelled: A rare find of a mummified child from the 16th century AD, in Korea, with relatively preserved organs, enabled a search for ancient hepatitis B virus (aHBV) DNA sequences from laparoscopic-derived liver biopsies. Analysis of the complete aHBV genome (3,215 base pairs) revealed a unique HBV genotype C2 (HBV/C2) sequence commonly spread in Southeast Asia, which probably represents an HBV that infected the Joseon Dynasty population in Korea. Comparison of the aHBV sequences with contemporary HBV/C2 DNA sequences revealed distinctive differences along four open reading frames. Genetic diversity between contemporary and recovered aHBV/C2 DNA may be the result of immunologic, environmental, and/or pharmacologic pressures. The calculated time of most recent common ancestor suggests that the Korean HBV sequence origin dates back at least 3,000 years and possibly as long as 100,000 years. This isolate most likely represents the earliest human HBV sequence that colonized Southeast Asia by human migration., Conclusion: This study describes the complete sequence of the oldest HBV isolate and the most ancient full viral genome known so far., (Copyright © 2012 American Association for the Study of Liver Diseases.)

Purpose: This study aimed to estimate the prevalence and incidence of cerebrovascular disease (CVD) and stroke in Korean male adolescents., Materials and Methods: The authors reviewed all medical certificates, medical records, and radiologic images from the examinations of Korean military conscription from January 2008 to May 2011., Results: Of the 101,156 examinees, 40 had CVD and stroke during adolescence. The overall prevalence and incidence of CVD and stroke was 39.54 cases per 100,000 adolescents and 2.08 cases per 100,000 adolescents per year, respectively and these were similar to the worldwide data. There were 3 cases of aneurysm, 3 cases of dural arteriovenous fistula, 11 cases of arteriovenous malformation, 4 cases of cavernous hemangioma, 4 cases of cerebrovascular infarction, 16 cases of Moyamoya disease, and 1 case of missing data. The incidence of arteriovenous malformation (0.57 cases per 100,000 adolescents per year) was lower than the incidence for the worldwide general population. The incidence of Moyamoya disease was higher than that in any other country (15.82 cases per 100,000 adolescents, vs. 0.83 cases per 100,000 adolescents per year)., Conclusion: We observed ischemic and hemorrhagic stroke, each accounting for approximately half of cases, and high incidence of Moyamoya disease with low incidence of arteriovenous malformation in Korean male adolescents.