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Non-ablative Fractional Thulium Laser Irradiation Suppresses Early Tumor Growth

  • Yoo, Su Woong;Park, Hee-Jin;Oh, Gyungseok;Hwang, Soonjoo;Yun, Misun;Wang, Taejun;Seo, Young-Seok;Min, Jung-Joon;Kim, Ki Hean;Kim, Eung-Sam;Kim, Young L.;Chung, Euiheon
    • Current Optics and Photonics
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    • v.1 no.1
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    • pp.51-59
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    • 2017
  • In addition to its typical use for skin rejuvenation, fractional laser irradiation of early cancerous lesions may reduce the risk of tumor development as a byproduct of wound healing in the stroma after the controlled injury. While fractional ablative lasers are commonly used for cosmetic/aesthetic purposes (e.g., photorejuvenation, hair removal, and scar reduction), we propose a novel use of such laser treatments as a stromal treatment to delay tumorigenesis and suppress carcinogenesis. In this study, we found that non-ablative fractional laser (NAFL) irradiation may have a possible suppressive effect on early tumor growth in syngeneic mouse tumor models. We included two syngeneic mouse tumor models in irradiation groups and control groups. In the irradiation group, a thulium fiber based NAFL at 1927 nm was used to irradiate the skin area including the tumor injection region with 70 mJ/spot, while no laser irradiation was applied to the control group. Numerical simulation with the same experimental condition showed that thermal damage was confined only to the irradiation spots, sparing the adjacent tissue area. The irradiation groups of both tumor models showed smaller tumor volumes than the control group at an early tumor growth stage. We also detected elevated inflammatory cytokine levels a day after the NAFL irradiation. NAFL treatment of the stromal tissue could potentially be an alternative anticancer therapeutic modality for early tumorigenesis in a minimally invasive manner.

Recycling of Suspended Particulates by Atmospheric Boundary Depth and Coastal Circulation (대기경계층과 연안순환에 의한 부유입자의 재순환)

  • Choe, Hyo
    • Journal of Environmental Science International
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    • v.13 no.8
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    • pp.721-731
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    • 2004
  • The dispersion of suspended particulates in the coastal complex terrain of mountain-inland basin (city)-sea, considering their recycling was investigated using three-dimensional non-hydrostatic numerical model and lagrangian particle model (or random walk model). Convective boundary layer under synoptic scale westerly wind is developed with a thickness of about I km over the ground in the west of the mountain, while a thickness of thermal internal boundary layer (TIBL) is only confined to less than 200m along the eastern slope of the mountain, below an easterly sea breeze circulation. At the mid of the eastern slop of the mountain, westerly wind confronts easterly sea breeze, which goes to the height of 1700 m above sea level and is finally eastward return flow toward the sea. At this time, particulates floated from the ground surface of the city to the top of TIBL go along the eastern slope of the mountain in the passage of sea breeze, being away the TIBL and reach near the top of the mountain. Then those particulates disperse eastward below the height of sea-breeze circulation and widely spread out over the coastal sea. Total suspended particulate concentration near the ground surface of the city is very low. On the other hand, nighttime radiative cooling produces a shallow nocturnal surface inversion layer (NSIL) of 200 m thickness over the inland surface, but relatively thin thickness less than 100m is found near the mountain surface. As synoptic scale westerly wind should be intensified under the association of mountain wind along the eastern slope of mountain to inland plain and further combine with land-breeze from inland plain toward sea, resulting in strong wind as internal gravity waves with a hydraulic jump motion bounding up to about 1km upper level in the atmosphere in the west of the city and becoming a eastward return flow. Simultaneously, wind near the eastern coastal side of the city was moderate. Since the downward strong wind penetrated into the city, the particulate matters floated near the top of the mountain in the day also moved down along the eastern slope of the mountain, reaching the. downtown and merging in the ground surface inside the NSIL with a maximum ground level concentration of total suspended particulates (TSP) at 0300 LST. Some of them were bounded up from the ground surface to the 1km upper level and the others were forward to the coastal sea surface, showing their dispersions from the coastal NSIL toward the propagation area of internal gravity waves. On the next day at 0600 LST and 0900 LST, the dispersed particulates into the coastal sea could return to the coastal inland area under the influence of sea breeze and the recycled particulates combine with emitted ones from the ground surface, resulting in relatively high TSP concentration. Later, they float again up to the thermal internal boundary layer, following sea breeze circulation.

A Study on the Computational Simulation of Cyclic Voltammetry using Semi-infinite Diffusion Model (반무한 확산모델을 이용한 순환전위법의 전산모사에 관한 연구)

  • Cho, Ha-Na;Kim, Tae-Yong;Yoon, Do-Young
    • Journal of the Korean Electrochemical Society
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    • v.14 no.3
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    • pp.138-144
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    • 2011
  • The transport phenomena of electron and ion around the electrode have been analyzed, herein the computational program to simulate the electrochemical signal of cyclic voltammetry has been implemented. For the dominant mass-transfer system, the governing equation and its boundary conditions are confined to the semi-infinite diffusion model and the reversible reaction at the electrode. In order to obtain the numerical solutions of cyclic voltammetry, MATLAB was used for the explicit finite difference method. Experimental results from the cyclic voltammetry of electrochemical system(10 mM $K_3Fe(CN)_6$ and 0.1M KCl) upon the ITO glass substrate were compared with the numerical solutions. Present program explains the experimental results fairly well, where they approached the simulated ones closely with deceasing the scan rate. Furthermore, the effects of electrode area, electrochemical reaction constants and transfering coefficients in the cyclic voltammetry were discussed quantitatively.

Phytoplankton Studies In Korean Waters 1. Phytoplankton Survey Of The Surface In The Korea Strait In Summer Of 1965 (한국해역의 식물플랑크톤의 연구 1. 1965년 하계의 한국해협 표층수의 식물 플랑크톤의 양과 분포)

  • Choe, Sang
    • 한국해양학회지
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    • v.1 no.1_2
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    • pp.14-21
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    • 1966
  • A phytoplankton study in the Korean waters has been commenced from 1964 as parts of the primary production studies in the Korean waters and the cruise for the cooperative studies of the Kuroshio from 1965 to 1968. Samples are taken by dipping 300-500 ml of sea water from the surface, and then fixed by adding neutralized formalin. The phytoplankton identification and cell counts are made on samples carefully after concentrated by decanting and centrifuging in the laboratory. This report deals with the surface phytoplankton obtained during the period of August 14-27, 1965 at twenty-three stations in the Korea Strait. Fifty nine species in seventeen genera of diatoms are detected from the samples collected at the stations. Among them seven species in five genera are considered to be purely neritic or cold water species and eight species in four genera are oceanic species of the Kuroshio. The highest phytoplankton standing crops are found in the sea area neighboring coastal waters of southern Korea, and the species distribution show anomalies in normally oceanic species being confined to neritic waters. There are distinct genera compositions of eastern, western and intermediate sea areas in the Kore Strait.

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A Back-Pressure Algorithm for Lifetime Extension of the Wireless Sensor Networks with Multi-Level Energy Thresholds (센서네트워크 수명 연장을 위한 에너지 임계값 기반 다단계 Back-Pressure 알고리즘)

  • Jeong, Dae-In
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.12B
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    • pp.1083-1096
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    • 2008
  • This paper proposes an energy-aware path management scheme, so-called the TBP(Threshold based Back-Pressure) algorithm, which is designed for lifetime extension of the energy-constrained wireless sensor networks. With the goal of fair energy consumptions, we extensively utilize the available paths between the source and the sink nodes. The traffic distribution feature of the TBP algorithm operates in two scales; the local and the whole routing area. The threshold and the back-pressure signal are introduced for implementing those operations. It is noticeable that the TBP algorithm maintains the scalability by defining both the threshold and the back-pressure signal to have their meanings locally confined to one hop only. Throughout several experiments, we observe that the TBP algorithm enhances the network-wide energy distribution. which implies the extension of the network lifetime. Additionally, both the delay and the throughput outcomes show remarkable improvements. This shows that the energy-aware path control scheme holds the effects of the congestion control.

Axial behavior of steel reinforced lightweight aggregate concrete columns: Analytical studies

  • Mostafa, Mostafa M.A.;Wu, Tao;Fu, Bo
    • Steel and Composite Structures
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    • v.38 no.2
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    • pp.223-239
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    • 2021
  • This paper presents the analytical modeling and finite element (FE) analysis, using ABAQUS software, of the new types of steel reinforced lightweight aggregate concrete (SRLAC) columns with cross-shaped (+shaped and X-shaped) steel section, using proposed three analytical and two FE models in total. The stress-strain material models for different components in the columns, including the confined zones of the lightweight aggregate concrete (LWAC) using three and four concrete zones divisions approaches and with and without taking into account the stirrups reaction effect, are established first. The analytical models for determining the axial load-deformation behavior of the SRLAC columns are drawn based on the materials models. The analytical and FE models' results are compared with previously reported test results of the axially loaded SRLAC columns. The proposed analytical and FE models accurately predict the axial behavior and capacities of the new types of SRLAC columns with acceptable agreements for the load-displacement curves. The LWAC strength, steel section ratio, and steel section configuration affect the contact stress between the concrete and steel sections. The average ratios of the ultimate test load to the three analytical models and FEA model loads, Put /Pa1, Put /Pa2, Put /Pa3, and Put /PFE1, for the tested specimens are 0.96, 1.004, 1.016, and 1.019, respectively. Finally, the analytical parametric studies are also studied, in terms of the effects of confinement, LWAC strength, steel section ratio, and the reinforcement ratio on the axial capacity of the SRLAC column. When concrete strength, confinements, area of steel sections, or reinforcement bars ratio increased, the axial capacities increased.

Change of the Scientific Name for the Opah in Korea to Lampris megalopsis (Lampridae, Lampriformes) (한국산 "붉평치"의 Lampris megalopsis(붉평치과, 이악어목)로의 학명 변경)

  • Yu-Jin Lee;Hak-Bin Hwang;Jin-Koo Kim
    • Korean Journal of Ichthyology
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    • v.35 no.2
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    • pp.136-140
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    • 2023
  • A single opah specimen (705 mm SL) was collected from Samcheok, South Korea on November, 2014, and firstly reported as Lampris guttatus by Jeong et al. (2015). Thereafter Lampris lauta was revived and three additional species (Lampris australensis, Lampris incognitus, Lampris megalopsis) were newly reported (Underkoffler et al., 2018). Therefore, it needs to review the scientific name of the Korean opah. The first reported opah specimen from Korea is now preserved as stuffed specimen at the Seodaemun Museum of Natural History in Seoul. We re-investigated the morphological features of stuffed specimen. It was characterized by having the following morphological combinations; orbital diameter is greater than 5% of fork length, whole body including head with white irregular spots, all fins are deep red. In addition, L. guttatus is confined to North Atlantic Ocean, whereas L. megalopsis is distributed worldwide from temperate to tropical waters. Therefore, our comprehensive study suggests that the scientific name of opah (L. guttatus) reported in Korea must be changed to L. megalopsis based on morphological characteristics and distribution area.

A Study on the Mediating Effect of Self-esteem on the Relationship between Economic Status and Happiness among the Elderly (노인의 경제상태가 행복에 미치는 영향: 자아존중감의 매개효과)

  • Yoon, Myeong Sook;Lee, Myo Sook
    • 한국노년학
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    • v.32 no.2
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    • pp.397-413
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    • 2012
  • The purpose of this study was to examine the mediating effect of self-esteem on the relationship between economic status and happiness among the elderly. The subjects of this study were 641 people over 65 years old around 4 metropolitan area. Structural Equation Modeling in AMOS 18.0 was adopted to examine measurement model and mediating effects of self-esteem by using Bootstrapping method. The results were as followings. First, subjects who had higher education, higher income, married, religion, higher marital satisfaction, no chronic disease, voluntary work participation showed more higher happiness. Second, the analysis resulted confined the full mediation effects of self-esteem in the relations between the economic status and happiness of the elderly. Based on these findings suggested that social work intervention service should be discussed to increase the level of self-esteem for the happiness among the elderly.

Abundance and Occupancy of Forest Mammals at Mijiang Area in the Lower Tumen River (두만강 하류 밀강 지역의 산림성 포유류 풍부도와 점유율)

  • Hai-Long Li;Chang-Yong Choi
    • Korean Journal of Environment and Ecology
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    • v.37 no.6
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    • pp.429-438
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    • 2023
  • The forest in the lower Tumen River serves as an important ecosystem spanning the territories of North Korea, Russia, and China, and it provides habitat and movement corridors for diverse mammals, including the endangered Amur tiger (Panthera tigris) and Amur leopard (Panthera pardus). This study focuses on the Mijiang area, situated as a potential ecological corridor connecting North Korea and China in the lower Tumen River, playing a crucial role in conserving and restoring the biodiversity of the Korean Peninsula. This study aimed to identify mammal species and estimate their relative abundance, occupancy, and distribution based on the 48 camera traps installed in the Mijiang area from May 2019 to May 2021. The results confirmed the presence of 18 mammal species in the Mijiang area, including large carnivores like tigers and leopards. Among the dominant mammals, four species of ungulates showed high occupancy and detection rates, particularly the Roe deer (Capreolus pygargus) and Wild boar (Sus scrofa). The roe deer was distributed across all areas with a predicted high occupancy rate of 0.97, influenced by altitude, urban residential areas, and patch density. Wild boars showed a predicted occupancy rate of 0.73 and were distributed throughout the entire area, with factors such as wetland ratio, grazing intensity, and spatial heterogeneity in aspects of the landscape influencing their occupancy and detection rates. Sika deer (Cervus nippon) exhibited a predicted occupancy rate of 0.48, confined to specific areas, influenced by slope, habitat fragmentation diversity affecting detection rates, and the ratio of open forests impacting occupancy. Water deer (Hydropotes inermis) displayed a very low occupancy rate of 0.06 along the Tumen River Basin, with higher occupancy in lower altitude areas and increased detection in locations with high spatial heterogeneity in aspects. This study confirmed that the Mijiang area serves as a habitat supporting diverse mammals in the lower Tumen River while also playing a crucial role in facilitating animal movement and habitat connectivity. Additionally, the occupancy prediction model developed in this study is expected to contribute to predicting mammal distribution within the disrupted Tumen River basin due to human interference and identifying and protecting potential ecological corridors in this transboundary region.

Welfare Regime of Park, Jeong-hee Authoritarian Anti-communism Developmental State. (박정희 정권시기 한국 복지체제: 반공개발국가, 복지국가의 기능적 등가물)

  • Yoon, Hongsik
    • 한국사회정책
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    • v.25 no.1
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    • pp.195-229
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    • 2018
  • This study has examined how the welfare system has changed as it has passed through the most controversial period in Korean modern history. The welfare system has changed in a way that adapts to the need for export-led economic growth. Industrialization centered on light industry, which started in the mid-1960s, absorbed the labor force that existed in the rural areas and commodified them, thereby creating a momentum for Korean society to get out of poverty. However, the public de-commodification, ie social security system, adapted to the commodification of the labor force has been institutionalized only in a very limited area and people. Indeed, the de-commodification system was confined to the area directly linked to the reproduction of the labor force. Even so, the target was very limited in the abundance of labor in rural areas. Compulsory medical insurance was rejected because of corporate burden, and industrial accidents insurance was introduced centering on large-scale workplaces. As the Korean economy began to move from the light industry to the heavy industry in the 1970s, the commodificated labor force changed from a low skilled labor force to a skilled male labor force. It is at this time that dual structures have begun to be created between workers employed in export-oriented large enterprises and workers employed in domestic-oriented SMEs. Therefore, the system of de-commodification that supports the reproduction of labor power in response to social risks has also been institutionalized centering on large-scale workplaces.