이 연구의 목적은 청년층의 이동이 인구 재분포에 미치는 영향을 분석하는 것이다. 이를 위해 청년층의 이동을 대학 진학과 취업 목적으로 구분하고, 다양한 스케일에서 조이동강도와 인구이동 유효도 지수를 산출하였다. 주요 연구 결과는 다음과 같다. 첫째, 대학 진학 관련 이동은 시군구뿐만 아니라 모든 스케일에서 인구 재분포에 상당히 큰 역할을 하고 있었다. 둘째, 취업 이동은 특정 권역에 집중되는 경향이 있었고, 이동 범위도 대학 진학을 위한 이동에 비해 상대적으로 좁은 범위에 국한되어 나타났다. 셋째, 청년층의 대학 및 취업을 위한 이동의 영향력은 성별에 따라 편차가 존재하였다. 넷째, 성비를 사례로 탐색한 결과 한 지역의 인구학적 결과는 청년층의 인구이동과 밀접한 관련성이 있는 것으로 판단된다. 본 연구의 결과는 향후 우리나라의 지역별 인구문제 진단 및 대응책 마련에 중요한 시사점을 제공한다.
원명교체기에 발발한 난수산의 난은 명나라 초기 중국 동남해안 해상 세력의 첫 번째 반란으로 명나라와 그 후세의 동아시아 해양정책에 깊은 영향을 미쳤다. 중국 쪽 사료에는 난수산의 난이 평정되었을 때 때까지 만 기록돼 있어 반란자인 난수산민들에 대한 후속처치 결과는 오랫동안 알려지지 않았다. 20세기 말에 이르러서야 학자들은 『이문』, 『고려사』, 『고려사절요』 등 한국사료를 이용하여 난수산의 난이 진압된 후에 난수 산민들이 한반도로 망명하게 된 경위를 밝혀졌다. 하지만 대부분 연구 성과는 사건 자체가 동아시아 해역의 국제정세에 미치는 영향을 중점적 으로 분석하였기 때문에 사건의 주인공인 난수산민들이 한반도에 망명하 게 된 후에 정착한 ‘이주’ 속성은 크게 부각되지 않았다. 본 연구는 선행 연구를 바탕으로 동아시아 이주사의 시각에서 한반도에 정착한 난수산민 들의 도주 행방, 인원 구성, 활동 지역, 생계 활동 등에 대한 분석을 통 해 그들이 한반도 서남해안지역을 이주지로 선택한 이유와 이주 이후 어 떻게 생활했는지를 밝혔다. 이를 통해 동아시아 이주사 연구의 새로운 역사 실마리를 더할 수 있을 것으로 기대된다.
악성 간문부 담관 폐쇄(malignant hilar biliary obstruction, MHBO) 치료를 위해 시행되는 내시경 담관배액술은 후속 치료, 생존율 및 환자 삶의 질 향상에 필수적이다. 그러나 간문부 담관의 복잡한 해부학적 특징으로 인해 시술의 난이도가 높고 시술 관련 우발증의 위험이 있다. 본 고에서는 완전 피막형 자가팽창성 금속 스텐트(fully covered self-expandable metal stent, fcSEMS)를 이용한 나란한 양측 삽입 담관배액술을 시행 후 근위부 담관내 이탈(proximal stent migration)이 발생한 증례를 보고한다. 현재까지 MHBO에 대해서는 어떤 종류의 스텐트를 어떠한 방법으로 시술할지에 대하여 충분한 근거가 정립되어 있지는 않다. 그렇지만 본 증례와 같이 fcSEMS를 사용할 경우 스텐트 이탈 위험성이 ucSEMS보다 높다는 것은 인지하고 있어야 하겠으며, 환자 진료 시 이러한 사항을 고려하여 적절한 대비가 필요하겠다. 향후 이러한 스텐트 이탈을 줄일 수 있는 다양한 예방법이 고안된다면 많은 도움이 될 것으로 기대 된다.
Climate change has made outbreaks of insect-transmitted plant viruses increasingly unpredictable. Understanding spatio-temporal dynamics of insect vector migration can help forecast virus outbreaks, but the relationship is often poorly characterized. The incidence of Beet curly top virus (BCTV) was examined in 2,196 tomato fields in California from 2013-2022. In addition, we experimentally showed dispersal of the beet leafhopper, the only known vector of BCTV is negatively correlated with plant greenness, and we estimated spring migration timing using a vegetation greenness-based model. Potential environmental factors and spring migration time of beet leafhoppers were associated with BCTV incidence. We found BCTV incidence is strongly associated with spring migration timing rather than environmental factors themselves. In addition, the vegetation greenness-based model was able to accurately predict the severe BCTV outbreaks in 2013 and 2021 in California. The predictive model for spring migration time was implemented into a web-based mapping system, serving as a decision support tool for management purposes.
An ameroid constrictor (AC) was placed to occlude the shunt vessel in a dog diagnosed with a single extrahepatic portocaval shunt, and the patient showed favorable outcomes post-surgery. However, the 1-year postoperative assessment revealed that the shunt vessel was completely occluded, but the AC had migrated into the abdominal cavity. The examination of the surgically removed migrated AC revealed an internal space filled with fibrous tissues with no swelling in the casein, and notably, the key remained securely in place. This is the first veterinary medicine case in which migration of the AC without dislodgement of ameroid key was identified.
심린 길은 싱가포르 태생으로 어린 시절 다양한 국가로 이주하며 성장하였다. <숲>은 그와 같은 길의 자전적 경험이 반영된 사진 작품이다. 길은 싱가포르와 말레 이시아에 있는 열대 숲의 식물들에 텍스트가 인쇄된 종이를 삽입한 후 16점의 흑백 사진을 촬영하여 <숲>을 구성하였다. 열대 식물에 이식된 종이 텍스트들은 그곳의 기후와 환경에 따라 식물과 함께 자라나거나 부패하는 등의 과정을 겪는다. 즉 낯선 장소로의 이식과 적응의 과정 거치는 것이다. 특히 <숲>이 제작된 장소와 길이 이용 한 종이 텍스트들은 과거 식민주의적 이주의 역사와 깊이 관련된 요소들이었다. 길은 이와 같은 <숲>을 통해 이주민으로서의 자신의 정체성뿐 아니라 식민주의적 이주가 이루어졌던 장소들의 의미 변화 과정을 이야기한다.
To ensure the safety of disposal facilities for radioactive waste, it is essential to quantitatively evaluate the performance of the waste disposal facilities by using safety assessment models. This paper addresses the development of the safety assessment model for the underground silo of Wolseong Low-and Immediate-Level Waste (LILW) disposal facility in Korea. As the simulated result, the nuclides diffused from the waste were kept inside the silo without the leakage of those while the integrity of the concrete is maintained. After the degradation of concrete, radionuclides migrate in the same direction as the groundwater flow by mainly advection mechanism. The release of radionuclides has a positive linear relationship with a half-life in the range of medium half-life. Additionally, the solidified waste form delays and reduces the migration of radionuclides through the interaction between the nuclides and the solidified medium. Herein, the phenomenon of this delay was implemented with the mass transfer coefficient of the flux node at numerical modeling. The solidification effects, which are delaying and reducing the leakage of nuclides, were maintained the integrity of the nuclides. This effect was decreased by increasing the half-life and the mass transfer coefficient of radionuclides.
The Colloid Formation and Migration (CFM) international joint research initiative continues as a part of the GTS’s Radionuclide Retardation Programme, which has been in progress since 1984. This project focuses on examining the formation of colloids from a bentonite-engineered barrier system and exploring how these colloids impact the migration of radionuclides in fractured host rock when subjected to advective flow. Phase 1 of the project was launched in 2004 and concluded in early 2008, focusing on preliminary studies related to in-situ boundary conditions, predicting models, and supplementary lab works. Following that, Phase 2 spanned from 2008 to 2013 and aimed at fortifying the field setup by adding three new monitoring boreholes and suitable instrumentation in both the boreholes and tunnel. This phase also tested the system’s resilience while mapping the flow domain. Phase 3 kicked off in January 2014 and extended until December 2018. During this period, the Long-term In-situ Test (LIT) was introduced in May 2014, featuring a set of compacted bentonite rings laced with radionuclide tracers. These were placed in a borehole to serve as a colloid and radionuclide source. CFM Phase 4 initiative commenced in January 2019, marking the successful deployment of the i-BET (In-situ Bentonite Erosion Test). This project component involves placing approximately 50 kg of compacted bentonite in a natural water-conducting shear zone. Korea Atomic Energy Research Institute (KAERI) joined CFM in 2008 to examine the behavior of colloid generation and migration with radionuclides in the Underground Research Laboratory. The fourth phase of the CFM project was also scheduled to include a post-mortem evaluation of the LIT and additional tracer experiments in the well-mapped MI shear zone. This study aims to provide an interim update on the ongoing i-BET, a key component of Phase 4 of the CFM project. We will also discuss the current status of the post-mortem analysis for the LIT experiment. In addition, we will outline plans for the forthcoming Phase VI of the project. These plans will continue to advance our understanding of radionuclide migration and the influence of bentonite-based disposal systems.
멸강나방은 중국 내 개체군이 북쪽 지역으로 2차 이주를 할 때, 봄철 제트기류를 타고 국내로 유입되는 비래해 충이다. 집단으로 발생 시 벼, 옥수수, 수수 등 여러 작물에 큰 피해를 준다. 2020년과 2021년 북방접경 세 지역(백령 도, 연천, 고성)과 수원 지역에서 성페로몬트랩을 이용하여 멸강나방의 성충 발생 시기를 탐지하였다. 일반적으 로 수원지역은 4월 하순 혹은 5월 상순에 최초 유인되었으나 두 해 여러 지역에서 공통적으로 탐지되는 시기는 6월 초중순이었다. 미국 해양대기청(NOAA)에서 제공하는 역궤적 분석프로그램(HYSPLIT)을 이용하여 각 지 역에서 멸강나방이 포획된 날짜 별 지상 300, 500, 700, 1000 m의 36~72시간 역궤적 분석을 수행하였다. 이후 같은 시기에 중국 내 멸강나방이 분포할 가능성이 높은 지역(32~40 ºN)을 비래 근원지로 추정하였다. 2021년 수원과 백령도에서 공통적으로 산둥성(山东省)이 근원지로 추정되었다. 공통적으로 산둥성(山东省)과 장수성(江苏 省)이 주 비래지로 추정되었고, 추가적으로 백령도는 허베이성(河北省), 수원은 안후이성(安徽省), 허베이성(河 北省), 저장성(浙江省)도 가능성이 있는 지역으로 추정되었다.
Ctenoplusia agnata (Lepidoptera: Noctuidae) is a polyphagous pest that damage on crops belonging to the Fabaceae and Brassicaceae, and it is known as a migratory pest. In this study, we investigated pattern of occurrence to trace invasion characteristics using sex pheromone traps and conducted genetic analysis of captured individuals while also exploring their correlation with air currents. Our findings suggest that C.agnata exhibits an annual occurrence of four generations in Korea, with the second or third generation, primarily active from July to September, posing a significant threat to soybean. Genetic analysis revealed the presence of 17 haplotypes, and trajectory modeling confirmed the influence of air currents from Kyushu, Japan and Zhejiang, China etc. These results are expected to be used as a comprehensive management of C.agnata and other migratory moth species.
This research presents a conceptual framework for a comprehensive understanding of the causes of user migration from social media networking sites. The results of our survey show that users’ intentions to switch social media platforms are influenced by user satisfaction, alternative attractiveness, peer influence, and perceived switching costs.
The engineered barrier system (EBS) is an indispensable element of a deep geological repository (DGR) designed to prevent the discharge of radioactive materials into the environment. The buffer material is a vital component of the EBS by creating a physical and chemical barrier that prevents the migration of radioactive materials. In the disposal environment, gases can be generated from the corrosion of the canister. When the gas generation rate exceeds the diffusion rate, the buffer material’s performance can deteriorate by the physical damage induced by the increase in pore pressure. Therefore, understanding the EBS’s behavior under gas generation conditions is crucial to guarantee the longterm safety and performance of the DGR. Lab-scale and field-scale experiments have been conducted to examine the stability of the buffer material concerning gas generation and movement by the previous researchers. To evaluate long-term stability for more than 100,000 years, it is essential to assess stability using a numerical model verified by these experiments. This study investigated the effect of interfacial characteristics on the numerical modeling accuracy of experimental simulation while verifying a numerical model through field-scale experimental results. The findings of this study are expected to furnish fundamental data for establishing numerical analysis guidelines for the longterm stability assessment of disposal systems.
The safe disposal of high-level radioactive waste is a critical concern in many countries, especially in the context of the increasing use of nuclear power to overcome climate change. To provide a comprehensive understanding of the behavior of the radionuclides in the crystalline natural barrier, sorption of the artificially synthesized high-level radioactive waste (HLW) leachate was conducted. Granite (-1,000 m from ground level) and biotite gneiss (-100 m from ground level) rock cores were collected from Gyeongju and Gwacheon, respectively. The rock cores were milled with a jaw crusher and steel disk mill and then sieved. The crushed rocks with a diameter of 0.6 – 1.0 mm were selected, washed three times with deionized water, and then dried. To synthesize the simulated HLW leachate, representative elements (U(VI), Se(IV), Mo(VI), and Ni(II)) were added to natural groundwater collected from Gyeongju. The kinetic sorption experiment was performed in a polypropylene bottle with a solid-to-liquid ratio of 100 g/L in the orbital shaking incubator (200 rotations per min, 25.0°C). After the sorption, the supernatants were filtered by a 0.2-μm polytetrafluoroethylene syringe filter and subsequently analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). Through the kinetic change of aqueous concentration, the contact time has been determined to be 7 days. Ni(II) showed the highest distribution coefficients (Kd = 0.81 L/m2 for granite and 8 – 16 L/m2 for biotite gneiss), followed by U(VI) (Kd = 0.03 – 0.04 L/m2 for granite and 0.04 – 0.05 L/m2 for biotite gneiss). Highly mobile nuclides such as Se(IV) (Kd = 0.02 L/m2 for granite and 0.03 L/m2 for biotite gneiss) and Mo(VI) (Kd = 0.01 – 0.02 L/m2 for granite and 0.01 L/m2 for biotite gneiss) showed the lowest distribution coefficient. Our study provides insights into the migration-retention behaviors of the HLW leachate with granite and biotite gneiss in geological systems and verifies the sorption parameters, e.g., distribution coefficients, experimentally produced by other groups to ensure the safe disposal of HLW.
The surge in food delivery systems during the coronavirus 2019 pandemic necessitated this study of heavy metal migration from food contact materials (FCMs). A total of 104 samples of FCMs, comprising 51 polypropylene (PP), 21 polyethylene (PE), and 32 polystyrene (PS) samples of six different types of FCMs (containers, covers, table utensils, cups, pouches, and wrappers) used for food delivery distributed in Korea, were collected and investigated for migration of three heavy metals (Pb, Cd, and As) using inductively coupled plasma–mass spectrometry (ICP-MS) to determine whether they complied with Korea’s Standards and Specifications for Utensils, Containers, and Packages. Acetic acid (4%, v/v) was used as the food simulant, and tests were performed at 100oC (in harsh conditions) for 30 min. Linearity of Pb, Cd, and As showed acceptable results with a coefficient of determination (R2) value of 0.9999. Limit of detection (LOD) and limit of quantification (LOQ) of Pb, Cd, and As were 0.001, 0.001, and 0.001 μg/L and 0.002, 0.003, and 0.003 μg/L, respectively. Accuracy and precision results complied with the criteria presented in the European Commission Joint Research Centre guidelines. The average concentration of Pb, Cd, and As migration detected in a total of 104 samples was 0.009–0.260 μg/L, which was very low compared with the migration specification set in the Standards and Specifications for Utensils, Containers, and Packages. The maximum level of Pb corresponded to 0.23% of the migration limit. There were no samples exceeding the limit. Thus, this study confirmed that the heavy metal contents of FCMs used for delivery food distributed in Korea were safely managed. The data from this study represent an invaluable source for science-based safety management of hazardous heavy metals migrating from FCMs used in the food delivery industry.
본 논문의 주된 연구목적은 인구이동이 인구재분포에 미치는 영향력을 분석하기 위한 방법론적 토대를 공고히 하고, 그것을 바탕으로 우리나라 인구이동의 편향성 혹은 불균형성의 시공간적 역동성을 탐색하는 것이다. 방법론적인 측면에서, 인구이동 유효도 지수(MEI)가 순이동률(NMR)에 비해 보다 적절한 측도인 것으로 판단되었다. MEI는 NMR에 비해 측도로서의 타당도가 높으며, ‘소인구문제’로부터 상대적으로 자유롭고, 인구이동의 현재적 역동성을 파악하는데 상대적으로 유리한 것으로 평가되었다. 덧붙여 MEI는 NMR에 비해 스케일 확장성이 월등해 다중 스케일을 고려한 연구 프레임워크의 수립에 훨씬 유리한 것으로 판단되었다. MEI에 기반한 분석 프레임워크를 우리나라의 최근 25년간(1998~2022년)의 데이터에 적용하여 분석하였다. 연구 결과를 요약하면 다음과 같다. 첫째, 전역 스케일의 분석 결과, 지난 25년간 전역적 MEI 값이 대략 5~10% 안에서 변동하는 경향을 보였으며, 특정한 시계열적 패턴을 보여주었다. 둘째, 지역별 스케일 분석의 결과, MEI가 NMR에 비해 인구이동의 역동성을 파악하는데 더 적절한 도구라는 사실이 입증되었다. 셋째, 지역-특수적 스케일 분석의 결과, 특별・광역시별로 매우 독특한 인구 교환 양상의 패턴이 드러났으며, 스케일 확장성이라는 측면에서 MEI는 NMR에 비해 월등하다는 사실이 입증되었다. 넷째, 지역간 스케일의 분석 결과, 인구이동 편향성이 두드러진 플로들이 확인되었다. 본 연구에서 제시된 연구 프레임워크는 다양한 방향으로 확장될 수 있는데, 집단 개별화 연구, 다변량 기법의 적용, 보다 작은 공간단위의 연구 등이다.
Oral squamous cell carcinoma (OSCC) is the most common type of head and neck cancer and is associated with high recurrence, poor treatment, and low survival rates. Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that regulates the response to hypoxia, a major factor in the tumor microenvironment that affects tumor development and progression in various cancer types. However, microRNA (miRNA) sequence analysis revealed that only a few miRNAs targeting HIF-1α had been discovered. In the present study, we investigated HIF-1α expression in OSCC and the effect of HIF-1α-targeting miRNAs on the progression and metastatic potential of OSCC. We analyzed public databases to explore which miRNAs target HIF-1α expression. In addition, the expression of proteins involved in the cell cycle, proliferation, and apoptosis in HSC-2 cells was analyzed after miRNA-126 mimic treatment. Furthermore, to investigate the effect of miRNA-126 on the proliferation and invasion ability of OSCC cells, 5-ethynyl-2′-deoxyuridine and Transwell assays were performed. The activities of MMP-2 and MMP-9 were evaluated via gelatin zymography. Our results showed that miRNA-126, which targets HIF-1α, enhances OSCC cell proliferation by regulating the cell cycle and reinforces the cell mobility of OSCC via HIF-1α expression. These findings suggest that miRNA-126 may be a novel marker for OSCC treatment and the development of new tools for patients with OSCC.
Colloid Formation and Migration (CFM) project is being carried out within the Grimsel Test Site (GTS) Phase Ⅵ. Since 2008, the Korea Atomic Energy Research Institute (KAERI) has joined CFM to investigate the behavior of colloid-facilitated radionuclide transport in a generic Underground Research Laboratory (URL). The CFM project includes a long-term in-situ test (LIT) and an in-rock bentonite erosion test (i-BET) to assess the in-situ colloid-facilitated radionuclide transport through the bentonite erosion in the natural flow field. In the LIT experiment, radionuclide-containing compacted bentonite was equipped with a triple-packer system and then positioned at the borehole in the shear zone. It was observed that colloid transport was limited owing to the low swelling pressure and low hydraulic conductivity. Therefore, a postmortem analysis is being conducted to estimate the partial migration and diffusion of radionuclides. The i-BET experiment, that focuses more on bentonite erosion, was newly designed to assess colloid formation in another flow field. The i-BET experiment started with the placement of compacted bentonite rings in the double-packer system, and the hydraulic parameters and bentonite erosion have been monitored since December 2018.
Bioactive flavonoids have been shown to improve the biological activity of stem cells derived from different sources in tissue regeneration. The goal of this study was to see how naringin, a natural flavonoid discovered in citrus fruits, affected the biological properties of human dental pulp stem cells (HDPSCs). In this study, we found that naringin increases the migratory ability of HDPSCs. Naringin increased matrix metalloproteinase-2 (MMP-2) and C-X-C chemokine receptor type 4 (CXCR4) mRNA and protein expression in HDPSCs. ARP100, a selective MMP-2 inhibitor, and AMD3100, a CXCR4 antagonist, both inhibited the naringin-induced migration of HDPSCs. Furthermore, naringin increased osteogenic differentiation of HDPSCs and the expression of the osteogenic-related marker, alkaline phosphatase in HDPSCs. Taken together, our findings suggest that naringin may be beneficial on dental tissue or bone regeneration by increasing the biological activities of HDPSCs.
This paper explores the effect of the digital economy on human migration in Guangdong Province. This paper measures the effect of digital economy development on human migration in 21 prefecture-level cities in Guangdong Province, China, from 2011 to 2019 using a fixed-effects model. The results of this study show that there is a significant positive effect of digital economy on net migration rate, and there is a significant negative effect on emigration rates. There is also a significant pull effect of economic development level and health-care level on migration. This finding holds after introducing instrumental variables estimation. This study provides explanatory mechanisms and empirical evidence for the development of digital economy and human migration, which helps to understand the mechanism of action between the development of digital economy and human migration. On this basis, this study puts forward policy recommendations, which provide some reference basis for the formulation of policies on digital economy and talent introduction in Guangdong Province.