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Effects of Endocrine Disrupting Chemicals on the Nervous System (내분비계 교란물질이 신경계에 미치는 영향)

  • Shin, Hyun Seung;Wi, Jae Ho;Lee, Seung Hyun;Choi, Soo Min;Jung, Eui-Man
    • Journal of Life Science
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    • v.32 no.1
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    • pp.70-77
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    • 2022
  • Endocrine disrupting chemicals (EDCs) have been attracting significant attention in modern society, owing to the increased incidence rate of various diseases along with population growth. EDCs are found in many commercial products, including some plastic bottles and containers, detergents, liners of metal food cans, flame retardants, food, toys, cosmetics, and pesticides. EDCs have a hormonal effect on the human body, which disrupts the endocrine system, notably affecting sexual differentiation and normal reproduction, and can trigger cancer as well. Recently, the association between neurological diseases and EDCs has become a hot topic of research in the field of neuroscience. Considering that EDCs negatively affect not only neuronal proliferation and neurotransmission but also the formation of the neuronal networks, EDCs may induce neurodevelopmental disorders, such as autism spectrum disorders and attention-deficit/hyperactivity disorder as well as neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. In light of these potentially deleterious outcomes, important efforts have been underway to minimize the exposure to EDCs through appropriate regulations and policies around the world, but chemicals that have not yet been associated with endocrine disrupting properties are still in wide use. Therefore, more epidemiological investigations and research are needed to fully understand the effects of EDCs on the nervous system.

DOI Detector Design using Different Sized Scintillators in Each Layer (각 층의 서로 다른 크기의 섬광체를 사용한 반응 깊이 측정 검출기 설계)

  • Seung-Jae, Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.1
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    • pp.11-16
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    • 2023
  • In preclinical positron emisson tomography(PET), spatial resolution degradation occurs outside the field of view(FOV). To solve this problem, a depth of interaction(DOI) detector was developed that measures the position where gamma rays and the scintillator interact. There are a method in which a scintillation pixel array is composed of multiple layers, a method in which photosensors are arranged at both ends of a single layer, a method in which a scintillation pixel array is constituted in several layers and a photosensor is arranged in each layer. In this study, a new type of DOI detector was designed by analyzing the characteristics of the previously developed detectors. In the two-layer detector, different sizes of scintillation pixels were used for each layer, and the array size was configured differently. When configured in this form, the positions of the scintillation pixels for each layer are arranged to be shifted from each other, so that they are imaged at different positions in a flood image. DETECT2000 simulation was performed to confirm the possibility of measuring the depth of interaction of the designed detector. A flood image was reconstructed from a light signal acquired by a gamma-ray event generated at the center of each scintillation pixel. As a result, it was confirmed that all scintillation pixels for each layer were separated from the reconstructed flood image and imaged to measure the interaction depth. When this detector is applied to preclinical PET, it is considered that excellent images can be obtained by improving spatial resolution.

A Literature Review of Tongue Movement and Measurement Tools for Dysphagia (연하장애 환자의 혀 운동 및 측정 도구에 대한 고찰)

  • Kim, Jin-Yeong;Son, Yeong-Soo;Hong, Deok-Gi
    • Therapeutic Science for Rehabilitation
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    • v.11 no.4
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    • pp.55-68
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    • 2022
  • Objective : This review aimed to provide information for clinical application by confirming the principles and characteristics of the tool through a review of tongue movement and measurement tools for patients with swallowing disorders. Results : We identified 15 tools used as tongue exercises and measurement tools in the field of dysphagia. According to principle, the tools were classified as either a bulb sensor, resistive sensor sheet, mouthpiece with sensor, or other techniques. The bulb sensor was easy to use but had limitations in fixing the position when measuring tongue pressure. The resistive sensor sheet could be measured at a more stable position than the bulb sensor. A mouthpiece with a sensor could be used in an individual's oral cavity such that the position was fixed when measuring the tongue pressure. Other techniques had the advantage of being wireless and capable of sensing light. Conclusion : Based on this literature review, it is necessary to facilitate the selection of the best tool for quantitative tongue measurement in dysphagia. The review can also be used to develop a Korean tongue movement tool model that can be used in hospitals and community centers.

Physiological and Psychological Responses to Landscape Experiences in a Natural Forest and a VR Forest (자연숲과 VR숲의 경관 체험에 따른 생리 및 심리적 반응)

  • Kim, Il-Doo;Shin, Won-Soep
    • Korean Journal of Environment and Ecology
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    • v.36 no.5
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    • pp.525-534
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    • 2022
  • In this study, we investigated the psychological and physiological effects of experiences in real natural forests and virtual forests using artificially controllable VR. The experiment tested 60 adult college students in a natural forest and a graduate seminar room where external light was blocked. It evaluated the effects of the natural and the VR forest environments by comparing the psychological and physiological recovery of the subjects. Psychometric testing using the PANAS psychological index showed increased positive emotions and decreased negative emotions after experiencing forest scenery in the natural and VR forest environments. And a stress index, based on measuring cortisol in saliva, decreased significantly in the subjects in both environments. The experiment results can be used to support the creation of a psychological and physiological recovery environment with VR for those who cannot go to the natural forest due to certain restrictions such as physical distance, mobility difficulties, etc. It is expected that the results will be the basis for further research into the visual effects of forest healing and also for widening the use of VR, a technology of the fourth industry, in the field of forestry.

Comprehensive Literature Study on Efficacy of Marine Therapeutic Resources (해양치유자원의 효능관련 기존의 연구문헌 분석)

  • Kim, Choong-Gon;Cho, Hyeon-Jin
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.4
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    • pp.121-136
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    • 2022
  • Purpose : Marine therapy is an activity that promotes public health such as constitution improvement, immunity improvement, and anti-aging by utilizing marine therapeutic resources such as seawater, mud, seaweed, salt and sea climate. In Europe developed countries, the marine therapy industry has been developing for centuries, with France, Germany, and Israel leading the way. Currently, it has achieved great industrial achievements and is of great help in improving the human health. The purpose of this study is to investigate how marine therapeutic resources benefit to human health, as well as how to study and utilize their efficacy. We analyzed previous research articles related to the effects of marine therapeutic resources. Methods : The study included a total of 830 published literatures in the last 20 years from the Republic of Korea and other contries. PubMed and Google Scholar were utilized to collect the foreign source while the local scientific publications were accessed through the Korean Education and research Information Service (KERIS) and Korean studies Information Service System (KISS). The keywords used to search foreign literature were "marine therapy", "Thalassotherapy", "seawater", "deep seawater", "saline groundwater", "sand therapy", "mud therapy", "hydrotherapy", "seaweed", "Sun light", "sea salt", "marine animal", and "marine microorganisms" were combined, and for the domestic literature, the keywords were "marine therapy", "marine therapeutic resources", "seawater", and "sand". Results : A total of 830 research papers were found as a result of searching for domestic and international papers related to marine therapeutic resources. The collected documents were classified into 175 seawater resources, 259 marine mineral resources, 41 marine environment, and 355 marine organisms. The efficacy of each marine therapeutic resources was analyzed. By resources type, there were about 213 papers on the efficacy of seaweed, followed by about 175 papers on seawater, 142 on microorganisms, 124 on mud/peat, and sand, salt, minerals and others are appeared in order (Table 1). Conclusion : Korea has the highest marine biodiversity index, excellent tidal flats, four distinct seasons, and various sea environments of the East sea, Yellow sea, South sea and Jeju sea. For this reason, Korea has a much more diverse marine therapeutic resources than other advanced countries in the marine therapy industry. prebiously, we thought that the sea was only valuable as a shipping port and fishery industry. But now, it been shown that the ocean can become a new industrial field which can contribute to human health and well-being by providing healing and therapy to people through the gift of marine resources.

A Study of the Characteristics of Highly Spatially Resolved CW-laser-based Aerosol Lidar (고공간분해능 연속 광원을 이용한 미세먼지 라이다의 신호 특성에 관한 연구)

  • Sim, Juhyeon;Kim, Taekeong;Ju, Sohee;Noh, Youngmin;Kim, Dukhyeon
    • Korean Journal of Optics and Photonics
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    • v.33 no.1
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    • pp.1-10
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    • 2022
  • In this study we introduce a new method for high-spatial-resolution continuous wave (CW) aerosol lidar that has a high spatial resolution in the near field and a low spatial resolution at long distances. A normal lidar system uses a nanosecond-pulse laser and measures the round-trip TOF between the aerosol and laser to obtain range resolution. In this study, however, we propose a new type of spatially resolving aerosol lidar that uses laser-scattering images. Using a laser-light-scattering image, we have calculated the distance of each scattering aerosol image for a given pixel, and recovered the short-range aerosol extinction. For this purpose, we have calculated the distance image and the contribution range of the aerosol to the given one-pixel image, and finally we have calculated the extinction coefficients of the aerosol with range-resolved information. In the case of traditional aerosol lidar, we can only obtain the aerosol extinction coefficients above 400 m. Using our suggested method, it was possible to extend the range of the extinction coefficient lower then several tens of meters. Finally, we can remove the unknown short-range region of pulsed aerosol lidar using our method.

Perceptions of Academic Journals and Scholarly Events in Library and Information Science: An Online Survey (문헌정보학 분야 학술지 및 학술행사 인식 연구 - 설문조사 결과를 중심으로 -)

  • Jongwook Lee;Soojung Kim;Sanghee Oh
    • Journal of the Korean Society for Library and Information Science
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    • v.57 no.1
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    • pp.365-386
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    • 2023
  • The purpose of this study is to investigate the perception of academic journals and scholarly events published and operated by the four major academic societies in library and information science (Korean Library and Information Science Society, Korean Society for Library and Information Science, Korean Biblia Society for Library and Information Science, and Korea Society for Information Management). An online survey was carried out to know the members' perceptions of journals' quality, number, review process, publication/distribution, readership, practicality, interdisciplinarity, internationalization, and differentiation. In addition, the reasons for participation and non-participation in scholarly events, the degree of achievement of the purpose, differentiation between scholarly events, and ways to revitalize joint academic conferences were examined. A total of 197 members of the four societies completed the survey. The findings showed that the overall quality of the four journals was good, but they still needed to be improved in the review process, publication and distribution, readership, practicality, and internationalization. Strategies to specialize each journal needed to be considered as well. To revitalize scholarly events, large-scale joint academic conferences can be organized to encourage the participation of researchers and practitioners, considering both academic and social aspects of research and practice. This study mainly reported the results of the online survey. Also, it shed light on the suggestions to improve the academic journals and scholarly events in the field of library and information science based on the findings from the case studies of international academic journals and events as well as the group discussions and feedback from the participants at the joint conferenece held in December 2022.

Growth and Photocurrent Properties of $CuGaSe_2$ Single Crystal ($CuGaSe_2$ 단결정 박막 성장과 광전류 특성)

  • K.J. Hong
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.03a
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    • pp.81-81
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    • 2003
  • The stochiometric mixture of evaporating materials for the CuGaSe$_2$ single crystal thin films were prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal CuGaSe$_2$, it was found tetragonal structure whose lattice constant no and co were 5.615$\AA$ and 11.025$\AA$, respectively. To obtains the single crystal thin films, CuGaSe$_2$ mixed crystal was deposited on throughly etched GaAs(100) by the Hot Wall Epitaxy(HWE) system. The source and substrate temperature were 61$0^{\circ}C$ and 45$0^{\circ}C$ respectively, and the growth rate of the single crystal thin films was about 0.5${\mu}{\textrm}{m}$/h. The crystalline structure of single crystal thin films was investigated by the double crystal X-ray diffraction(DCXD). Hall effect on this sample was measured by the method of van der pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30K to 150K and by polar optical scattering in the temperature range 150K to 293K. The optical energy gaps were found to be 1.68eV for CuGaSe$_2$ single crystal thin films at room temperature. The temperature dependence of the photocurrent peak energy is well explained by the Varshni equation then the constants in the Varshni equation are given by a=9.615$\times$ 10$^{-4}$ eV/K, and $\beta$=335K. From the photocurrent spectra by illumination of polarized light of the CuGaSe$_2$ single crystal thin films. We have found that values of spin orbit coupling ΔSo and crystal field splitting ΔCr was 0.0900eV and 0.2498eV, respectively. From the PL spectra at 20K, the peaks corresponding to free bound excitons and D-A pair and a broad emission band due to SA is identified. The binding energy of the free excitons are determined to be 0.0626eV and the dissipation energy of the acceptor-bound exciton and donor-bound exciton to be 0.0352eV, 0.0932eV, respectively.

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Quality Improvement in Perilla III. Varietal Differences of Protein Content and Amino Acid Composition in Perilla (들깨의 성분개량 연구 III. 들깨 품종의 단백질 함량과 아미노산 조성)

  • Lee, Jung-Il;Park, Chung-Berm;Son, Seuk-Yeong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.1
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    • pp.15-22
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    • 1993
  • Korean local collected strains of perilla were analyzed on their protein and amino-acid contents in the seed. The strains analyzed were 80 of which grown in the experimental field of Crop Experiment Station at Suwon in 1991. This experiment was performed to obtain the basic informations on the varietal differences of protein and amino-acid contents and further applied in the breeding project for quality improvement of perilla. The seed protein contents of 80 perilla varieties ranged from 17.9% to 24.6% and the average content was 24.6%. There were no differences in protein contents according to the maturity and 1,000 seed weight, but differed by the seed coat color showing 1.4% higher content in light gray than that of drak brown, which may suggest that the seed coat color could be used as a marker gene for breeding high protein varieties. While the total essential amino-acid contents of collected perilla ranged from 36.41% to 44.85%, the mean of 40.55%, the non-essential amino-acid contents was 47.23%~60.01% with the mean of 55.29%. Moreover, there was high positive correlation between the essential amino-acid contents and seed coat color. The essential amino-acids of perilla has an exceptionally high content of arginine, leucine, but methionine indeed being almost marginal. Of the essential amino-acids, lysine, methionine and valine were contained higher compared with the FAO recommendation level.

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D4AR - A 4-DIMENSIONAL AUGMENTED REALITY - MODEL FOR AUTOMATION AND VISUALIZATION OF CONSTRUCTION PROGRESS MONITORING

  • Mani Golparvar-Fard;Feniosky Pena-Mora
    • International conference on construction engineering and project management
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    • 2009.05a
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    • pp.30-31
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    • 2009
  • Early detection of schedule delay in field construction activities is vital to project management. It provides the opportunity to initiate remedial actions and increases the chance of controlling such overruns or minimizing their impacts. This entails project managers to design, implement, and maintain a systematic approach for progress monitoring to promptly identify, process and communicate discrepancies between actual and as-planned performances as early as possible. Despite importance, systematic implementation of progress monitoring is challenging: (1) Current progress monitoring is time-consuming as it needs extensive as-planned and as-built data collection; (2) The excessive amount of work required to be performed may cause human-errors and reduce the quality of manually collected data and since only an approximate visual inspection is usually performed, makes the collected data subjective; (3) Existing methods of progress monitoring are also non-systematic and may also create a time-lag between the time progress is reported and the time progress is actually accomplished; (4) Progress reports are visually complex, and do not reflect spatial aspects of construction; and (5) Current reporting methods increase the time required to describe and explain progress in coordination meetings and in turn could delay the decision making process. In summary, with current methods, it may be not be easy to understand the progress situation clearly and quickly. To overcome such inefficiencies, this research focuses on exploring application of unsorted daily progress photograph logs - available on any construction site - as well as IFC-based 4D models for progress monitoring. Our approach is based on computing, from the images themselves, the photographer's locations and orientations, along with a sparse 3D geometric representation of the as-built scene using daily progress photographs and superimposition of the reconstructed scene over the as-planned 4D model. Within such an environment, progress photographs are registered in the virtual as-planned environment, allowing a large unstructured collection of daily construction images to be interactively explored. In addition, sparse reconstructed scenes superimposed over 4D models allow site images to be geo-registered with the as-planned components and consequently, a location-based image processing technique to be implemented and progress data to be extracted automatically. The result of progress comparison study between as-planned and as-built performances can subsequently be visualized in the D4AR - 4D Augmented Reality - environment using a traffic light metaphor. In such an environment, project participants would be able to: 1) use the 4D as-planned model as a baseline for progress monitoring, compare it to daily construction photographs and study workspace logistics; 2) interactively and remotely explore registered construction photographs in a 3D environment; 3) analyze registered images and quantify as-built progress; 4) measure discrepancies between as-planned and as-built performances; and 5) visually represent progress discrepancies through superimposition of 4D as-planned models over progress photographs, make control decisions and effectively communicate those with project participants. We present our preliminary results on two ongoing construction projects and discuss implementation, perceived benefits and future potential enhancement of this new technology in construction, in all fronts of automatic data collection, processing and communication.

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