• Title/Summary/Keyword: Lee Sam

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Study on the Methods of Detection and Analysis for Responding Inorganic Acids Spill (무기산 누출 사고 대응을 위한 탐지·분석 방법 연구)

  • Lee, Jin Seon;Jung, Mi Suk;Kim, Ki Joon;Ahn, Sung Young;Yoon, Young Sam;Yoon, Junheon
    • Korean Journal of Hazardous Materials
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    • v.2 no.1
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    • pp.6-11
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    • 2014
  • There have been frequent chemical leaks over the past 10 years. Particularly, inorganic acids like sulfuric acid, nitric acid, and hydrogen chloride take up 37 % of the total chemical accidents which took place for the past 10 years. When an acid chemical leak happens, fume is generated, diffusing into the air, which might cause serious damage to health of local residents and the environment. However, most of the acid-based chemicals, detecting and analysis methods have not been settled considering the frequency of accidents. In this study, we investigated detection and analysis methods to quickly analyze accident sites and evaluate the impacts on environments. Reviewing local and international test analysis methods of acids suggested that nitric acid, sulfuric acid, hydrogen chloride and hydrogen fluoride can be analyzed with IC. It was also found that UV is better for the analysis of hydrogen fluoride and GC/MS for acrylic acid. The analytical methods suggested in the official test methods basically have limitations of consuming much time at stages of preparation and analysis. Considering prompt responses to chemical accidents, further studies should be done to compare the applicability of rapid monitoring methods such as FT-IR, IMR-MS and SIFT-MS.

Influence of a Pre- and Postconditioning Treadmill Exercise on Intracerebral Hemorrhage-induced Apoptotic Neuronal Cell Death in Rats

  • Ko, Il-Gyu;Shin, Mal-Soon;Sim, Young-Je;Kim, Chang-Ju;Lee, Sam-Jun
    • Korean Journal of Exercise Nutrition
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    • v.13 no.2
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    • pp.115-122
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    • 2009
  • Intracerebral hemorrhage (ICH) is a common cause of stroke, and it occurs mainly in the striatum, thalamus, cerebellum, and pons. Physical exercise is known to ameliorate neurologic impairment induced by various brain insults. In the present study, the influence of pre-and post-conditioning of treadmill exercise on spatial learning ability, the lesion volume, and apoptotic neuronal cell death in the striatum following ICH in rats was investigated. ICH in the striatum was induced by injection of collagenase using strereotaxic instrument. The rats in the pre-exercise group were scheduled to run on a treadmill before ICH induction for 2 consecutive weeks. The rats in the post-exercise group were scheduled to run on a treadmill after ICH induction for 2 weeks. The rats in the pre-exercise and post-exercise group were scheduled to run on a preconditioning treadmill exercise 2 weeks before ICH induction until postconditioning treadmill exercise 2 weeks after ICH induction, except the day of surgery. For this study, radial arm maze task, Nissl staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and immunohistochemistry for caspase-3 were performed. Our date showed that treadmill exercise suppressed the ICH-induced apoptotic neuronal cell death and decreased lesion volume in the stratum. Treadmill exercise also alleviated the ICH-induced impairment of spatial learning ability. Preconditioning treadmill exercise before the ICH insult and postconditioning treadmill exercise after the ICH insult showed similar effectiveness on the recovery of ICH. In this study, however, preconditioning exercise before the ICH insult and postconditioning exercise after the ICH insult showed the most potent effectiveness on the recovery of ICH.

Treadmill exercise ameliorates post-traumatic stress disorder-induced memory impairment in Sprague-Dawley rats

  • Kim, Tae-Woon;Seo, Jin-Hee;Jung, Sun-Young;Kim, Dae-Young;Kim, Chang-Ju;Lee, Sam-Jun
    • Korean Journal of Exercise Nutrition
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    • v.15 no.4
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    • pp.173-182
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    • 2011
  • Post-traumatic stress disorder (PTSD) is a stress-related mental disorder induced by severe external stressors such as assault, disaster or severe accident. We investigated the effects of treadmill exercise on short-term memory in relation to apoptosis and cell proliferation in the hippocampus following PTSD. Stress to the pregnant rats was induced by exposure of maternal rats to the hunting dog in an enclosed room. Exposure time was 10 min, repeated three times per day, with 1 hour interval. Exposure of maternal rats to the hunting dog was continued 7 days after pregnancy until delivery. The pregnant rats in the exercise groups were forced to run on a treadmill for 30 min once a day for the same duration of stress exposure. Step-down avoidance task for short-term memory, western blot for Bcl-2, Bax, and immunohistochemistry for caspase-3, 5-bromo-2'-deoxyuridine (BrdU), and Ki-67 were conducted. Maternal rats exposed to stress during pregnancy showed short-term memory impairment. Expressions of Bax, Bcl-2, ratio of Bax to Bcl-2, and caspase-3 in the hippocampus were increased in the PTSD rats. Cell proliferation in the hippocampal dentate gyrus was decreased in the PTSD rats. Treadmill exercise alleviated short-term memory impairment and suppressed expressions of Bax, the ratio of Bax to Bcl-2, and caspase-3. Treadmill exercise also increased cell proliferation. The present results indicate that treadmill exercise alleviated PTSD-induced short-term memory impairment by suppressing apoptotic cell death and enhancing cell proliferation in the hippocampus.

The Effect of Scalp Acupuncture and rTMS on Neuromotor Function in Photothrombotic Stroke Rat Model

  • Jong-Seong Park;Eun-Jong Kim;Min-Keun Song;Jung-Kook Kim;Ganbold Selenge;Sam-Gyu Lee
    • Biomedical Science Letters
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    • v.29 no.4
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    • pp.263-273
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    • 2023
  • This study aimed to investigate effect of scalp acupuncture (SA) and repetitive transcranial magnetic stimulation (rTMS) intervention on neuromotor function in photothrombotic cerebral infarction (PCI) rat model. Sixty male SD rats were used. PCI was induced on M1 cortex of right frontal lobe. SA was performed at the Qianding (GV21), Xuanli (GB6) acupoints of ipsilesional M1. Low-frequency rTMS was delivered to contralesional M1. All rats were randomly divided into 4 groups: group A, normal (n, 15); group B, PCI without any stimulation intervention (n, 15); group C, PCI with SA (n, 15); group D, PCI with rTMS (n, 15). Rota-rod test and Ladder rung walking test (LWT) were done weekly for 8 weeks after PCI. SA or rTMS was started from post-PCI 4th day as protocol for 8 weeks. H/E stain and IHC were done. Western blot and qRT-PCR study were performed for MAP2 and BDNF from ipsilesional M1 peri-infarction tissue. Brain MRI study was conducted to quantify the volume of cerebral infarction. As a result, left forelimb and hindlimb function significantly improved more in group C and D than control group, with expressed more BDNF and MAP2. And brain MRI showed focal infarction of right M1 after PCI, and infarction volume progressively decreased in group C and D than group B from post-PCI 5th to 8th week. SA or rTMS was more effective than no intervention group on neuromotor function of PCI rat model. The functional recovery was associated with stimulation intervention-related neurogenesis.

Isolated unilateral temporalis muscle hypertrophy of unknown etiology: a case report and literature review

  • Jun Ho Choi;Seung Yeon Choi;Jae Ha Hwang;Kwang Seog Kim;Sam Yong Lee
    • Archives of Craniofacial Surgery
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    • v.24 no.6
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    • pp.278-283
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    • 2023
  • The initial instance of isolated unilateral temporalis muscle hypertrophy (IUTMH) was reported in 1990. Since then, only few cases have been documented. The cause of this condition remains ambiguous; however, it is presumed to be linked to compensatory and stress-induced hypertrophy. We introduce a rare case of the diagnosis and treatment of IUTMH. A 39-year-old woman presented with a steadily enlarging pain-free swelling on the left side of her face, first noticed a month ago. Apart from a hyperthyroidism medication regimen her medical history was unremarkable. She had no history of temporomandibular joint disease, bruxism, surgery, or trauma. However, she complained of having been under substantial stress lately. Contrast-enhanced magnetic resonance imaging revealed asymmetric temporalis muscle hypertrophy. The treatment plan consisted of administering type A botulinum toxin injections into left temporalis muscle, supplemented by lifestyle changes and relaxation techniques. At a follow-up visit 9 months after the injections, the muscle contour was normalized both in physical and in radiologic examinations. While further supportive evidence is needed, it can be anticipated that cosmetic treatment with botulinum toxin, rather than surgical interventions, will become the standard treatment of IUTMH.

$H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FIR Filters for Discrete-time State Space Models

  • Lee, Young-Sam;Jung, Soo-Yul;Seo, Joong-Eon;Han, Soo-Hee;Kwon, Wook-Hyun
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.401-404
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    • 2003
  • In this paper, $H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FIR filters are newly proposed for discrete-time state space signal models. The proposed filters require linearity, unbiased property, FIR structure, and independence of the initial state information in addition to the performance criteria in both $H_2$ and $H_{\infty}$ sense. It is shown that $H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FIR filter design problems can be converted into convex programming problems via linear matrix inequalities (LMIs) with a linear equality constraint. Simulation studies illustrat that the proposed FIR filter is more robust against uncertainties and has faster convergence than the conventional IIR filters. the conventional IIR filters.

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Effects of Sawdust and Urea Application on Disease Severity and Streptomyces scabiei Pathogen Dynamics (톱밥 및 요소의 투입이 감자 더뎅이병 병원균(Streptomyces scabiei) 및 감자 더뎅이병 이병도 지수에 미치는 영향)

  • Bak Gyeryeong;Lee Jeong-Tae;Jee Sam-nyu
    • Journal of Environmental Science International
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    • v.32 no.11
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    • pp.777-788
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    • 2023
  • Potato common scab disease is caused by pathogens belonging to Streptomyces spp. and results in a serious yield loss worldwide. Despite decades of research aimed at disease management, a definitive control method remains undiscovered. This study aims to explore the correlation between the C/N ratio and urea application with potato common scab pathogen dynamics and disease severity. We applied sawdust with a high C/N ratio and urea into the soil prior to potato cropping, both in pot and field experiments. Disease severity assessments and quantification of the TxtB gene were conducted at the harvest stage. Furthermore, culture experiments were performed to assess the direct impact of urea on the pathogen. Our findings revealed that higher disease severity was correlated with a high C/N ratio application and pathogenic gene quantity. Urea exhibited a direct influence on S. scabiei activity, reducing the disease severity in pot experiments. However, the effects of urea application on disease suppression in the conductive field were inconclusive. Although the results of urea application experiments displayed inconsistencies between pot and field trials, urea worked as the control to suppress S. scabiei activity. Further investigations are needed under various field conditions to confirm these findings.

Structural safety analysis for separator of young Mytilus galloprovincialis in marine farming (지중해담치 양식 어업 치패분리장비의 구조적 안전성 고찰)

  • Yong-Ju LEE;Sang-Hyuk PARK;Ju-Sam PARK
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.328-335
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    • 2023
  • In this paper, among the various facilities used in marine farming, young bivalves of the Mytilus galloprovincialis of marine farming was placed on the deck of the fishing vessel to evaluate the environment conditions and drive shaft movement by rolling affecting the separator for the young bivalves and a clean process. There were a few studies on stress analysis of development facilities because it was difficult to access the fishing site due to the use of imported equipment and the lack of development of domestic equipment. In this study, stress analysis of the fixed part of separator for young bivalves and its adjacent part was performed on various phases when the vessel was tilted by rolling using the finite element method. In addition, the structural safety of the internal blade under the driving conditions according to the movement of the drive shaft by the hydraulic motor was confirmed through structural analysis. As a result, the connection part between the deck and the separator by rolling was confirmed to have higher stress than that of other parts due to stress concentration. In addition, it was confirmed that the maximum stress occurred on the connection part between blades. Even though the safety of the separator for marine farming was confirmed by structural analysis, it is necessary to comprehensively consider the age of vessels, the material of the deck, and the corrosion of the deck.

Spiritual Care Guide in HospiceㆍPalliative Care

  • Kyung-Ah Kang;Do-Bong Kim;Su-Jin Koh;Myung-Hee Park;Hye Yoon Park;Deuk Hyoung Yoon;Soo-Jin Yoon;Su-Jeong Lee;JI-Eun Choi;Hyoung-Suk Han;Jiyoung Chun
    • Journal of Hospice and Palliative Care
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    • v.26 no.4
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    • pp.149-159
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    • 2023
  • The Spiritual Care Guide in HospiceㆍPalliative Care is evidence-based and focuses on the universal and integral aspects of human spirituality-such as meaning and purpose, interconnectedness, and transcendence-which go beyond any specific religion. This guide was crafted to improve the spiritual well-being of adult patients aged 19 and older, as well as their families, who are receiving end-of-life care. The provision of spiritual care in hospice and palliative settings aims to assist patients and their families in finding life's meaning and purpose, restoring love and relationships, and helping them come to terms with death while maintaining hope. It is recommended that spiritual needs and the interventions provided are periodically reassessed and evaluated, with the findings recorded. Additionally, hospice and palliative care teams are encouraged to pursue ongoing education and training in spiritual care. Although challenges exist in universally applying this guide across all hospice and palliative care organizations in Korea-due to varying resources and the specific environments of medical institutions-it is significant that the Korean Society for Hospice and Palliative Care has introduced a spiritual care guide poised to enhance the spiritual well-being and quality of care for hospice and palliative care patients.

Development and validation of a clinical phantom reproducing various lesions for oral and maxillofacial radiology research

  • Han-Gyeol Yeom;Jo-Eun Kim;Kyung-Hoe Huh;Won-Jin Yi;Min-Suk Heo;Sam-Sun Lee
    • Imaging Science in Dentistry
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    • v.53 no.4
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    • pp.345-353
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    • 2023
  • Purpose: The objective of this study was to propose a method for developing a clinical phantom to reproduce various diseases that are clinically prevalent in the field of dentistry. This could facilitate diverse clinical research without unnecessarily exposing patients to radiation. Materials and Methods: This study utilized a single dry skull, which was visually and radiographically examined to evaluate its condition. Existing lesions on the dry skull were preserved, and other relevant lesions were artificially created as necessary. These lesions were then documented using intraoral radiography and cone-beam computed tomography. Once all pre-existing and reproduced lesions were confirmed by the consensus of 2 oral and maxillofacial radiologists, the skull was embedded in a soft tissue substitute. To validate the process, cone-beam computed tomography scans and panoramic radiographs were obtained of the fabricated phantom. All acquired images were subsequently evaluated. Results: Most lesions could be identified on panoramic radiographs, although some sialoliths and cracked teeth were confirmed only through cone-beam computed tomographic images. A small gap was observed between the epoxy resin and the bone structures. However, 2 oral and maxillofacial radiologists agreed that this space did not meaningfully impact the interpretation process. Conclusion: The newly developed phantom has potential for use as a standardized phantom within the dental field. It may be utilized for a variety of imaging studies, not only for optimization purposes, but also for addressing other experimental issues related to both 2- and 3-dimensional diagnostic radiography.