Study of Nonstoichiometry and Physical Properties of the $Ca_xEu_{1-x}FeO_{3-y}$ System

Roh, Kwon-Sun,Ryu, Kwang-Sun,Ryu, Kwang-Hyun,Yo, Chul-Hyun Korean Chemical Society 1994 Bulletin of the Korean Chemical Society Vol.15 No.7

A series of samples of the ${Ca_xEu_{1-x}FeO_{3-y}$ (x=0.00, 0.25, 0.50, 0.75, and 1.00) system has been prepared at $1,250^{\circ}C$ under an atmospheric air pressure. X-ray diffraction analysis of the solid solution assigns the structure of the compositions of x=0.00, 0.25, 0.50, and 0.75 to the orthoferrite-type orthorhombic system, and that of x=1.00 to the brownmillerite-type orthorhombic one. The mole ratios of $Fe^{4+}$ ion in the solid solutions or ${\tau}$ values were determined by the Mohr's salt analysis and nonstoichiometric chemical formulas of the system were formulated from x, ${\tau}$, and y values. From the result of the Mossbauer spectroscopy, the coordination and magnetic property of the iron ion are discussed. The electrical conductivities are measured as a function of temperature. The activation energy is minimum at the composition of x=0.25. The conduction mechanism can be explained by the hopping of electrons between the mixed valences of $Fe^{3+}\;and\;Fe^{4+}$ ions.

간으로 전이된 소세포암의 면역조직화학적 및 전자현미경 관찰

노선희,정규원,박재정,문일환,배서은,유 권,조민선 이화여자대학교 의과대학 2009 EMJ (Ewha medical journal) Vol.32 No.1

Small cell lung cancer accounts for about 20% of all lung cancers. At the time of diagnosis, the majority of patients already have metastasis. The liver is one of the most common sites of distant metastasis of lung cancer. Small cell lung cancer arises from neuroendocrine cells which produce hormone, hormone producing granules can be seen under electron microscope . A 65-year-old male was admitted to hospital because of jaundice and right upper quadrant pain. The chest roentgenogram and chest computed tomography(CT) scan showed a 3 cm mass in right upper lobe with bilateral mediastinal lymphadenopathy and right pleural effusion. The abdomen CT scan revealed multiple masses in the liver with heterogenous pattern suggesting metastatic orgin. Though the immunohistochemistry and electron miscroscopy, he was diagnosed as metastatic small cell lung cancer of liver. We report a case of the Immunohistochemical and Electron Microscopic Observation of Metastatic Small Cell Lung Cancer of Liver.

The Clinical Meaning of Benign Colon Uptake in 18F-FDG PET: Comparison with Colonoscopic Findings

Sun Hee Roh,정성애,김성은,Hye-In Kim,Min Jin Lee,태정현,Ju Young Choi,심기남,정혜경,김태헌,Kwon Yoo,문일환,김범산 대한소화기내시경학회 2012 Clinical Endoscopy Vol.45 No.2

Background/Aims: Benign colon 18F-fluorodeoxyglucose (FDG) uptake is frequently observed in asymptomatic individuals. Aims of this study were to investigate the benign colon uptake by whole body FDG-positron emission tomography (PET) in asymptomatic adults and to correlate those results with colonoscopic and histologic findings. Methods: Among 3,540 subjects who had undergone FDG-PET, 43 subjects who were diagnosed to have benign colon uptake in FDG-PET and underwent colonoscopy were retrospectively reviewed. Subjects were classified as diffuse or focal groups based on their FDG uptake patterns. PET results were analyzed together with colonoscopic and histologic findings. Results: Forty-three subjects showed benign colon uptake in FDG-PET; 28 of them were shown as the diffuse group, while other 15 subjects were classified as the focal group. Five subjects among those showed diffuse uptake were diagnosed as adenoma. Seven among 15 subjects who showed focal uptake were diagnosed as adenocarcinoma (n=2), adenoma (n=3), or non-neoplastic polyp (n=2). Positive predictive values were 25% in the diffuse group and 47% in the focal group. Conclusions: We recommend that patients showing benign FDG uptake in the colon should be further evaluated by colonoscopy, especially for patients with focal FDG uptake.

Ecological Risk Assessment of Chemicals Migrated from a Recycled Plastic Product

Roh, Ji-Yeon,Kim, Min-Hyuck,Kim, Woo Il,Kang, Young-Yeul,Shin, Sun Kyoung,Kim, Jong-Guk,Kwon, Jung-Hwan The Korean Society of Environmental Toxicology 2013 환경독성보건학회지 Vol.28 No.-

Objectives: Potential environmental risks caused by chemicals that could be released from a recycled plastic product were assessed using a screening risk assessment procedure for chemicals in recycled products. Methods: Plastic slope protection blocks manufactured from recycled plastics were chosen as model recycled products. Ecological risks caused by four model chemicals - di-(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), cadmium (Cd), and lead (Pb)-were assessed. Two exposure models were built for soil below the block and a hypothetic stream receiving runoff water. Based on the predicted no-effect concentrations for the selected chemicals and exposure scenarios, the allowable leaching rates from and the allowable contents in the recycled plastic blocks were also derived. Results: Environmental risks posed by slope protection blocks were much higher in the soil compartment than in the hypothetic stream. The allowable concentrations in leachate were $1.0{\times}10^{-4}$, $1.2{\times}10^{-5}$, $9.5{\times}10^{-3}$, and $5.3{\times}10^{-3}mg/L$ for DEHP, DINP, Cd, and Pb, respectively. The allowable contents in the recycled products were $5.2{\times}10^{-3}$, $6.0{\times}10^{-4}$, $5.0{\times}10^{-1}$, and $2.7{\times}10^{-1}mg/kg$ for DEHP, DINP, Cd, and Pb, respectively. Conclusions: A systematic ecological risk assessment approach for slope protection blocks would be useful for regulatory decisions for setting the allowable emission rates of chemical contaminants, although the method needs refinement.

單調增加荷重을 받는 平面 트러스의 複合 非線型 擧動에 關한 硏究

權寧煥,金和中,金明璇,魯德煥 경북대학교 산업기술연구소 1990 産業技術硏究誌 Vol.18 No.-

The object of this study is that develop computer program as being derive simple formula considering complex (material and geometric) nonlinear, and select the most useful truss in efficiency with the analysis Howe truss, Fink truss, Pratt truss and Warren truss. The complex nonlinear behavior is considered in this paper, so is acquired following results. 1. We developed program that could analyze complex nonlinear of plane truss. 2. In view of the results analyzied the numerical analysis example of plane truss, When Howe truss, Fink truss, Pratt truss, and Warren truss are equal to weight and span, and the same load is loaded. Among the trusses of same weight, Warren truss is the most useful in efficiency. And When height of warren truss is changed, the lower height of truss, the more useful in efficiency

강박장애 환자의 인지기능이상에 대한 2년 추적 연구

노규식,신민섭,박희수,하태현,신용욱,김명선,권준수 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.5

Objectives : The purpose of this study was to investigate the changes of cognitive dysfunctions in patients with Obsessive-compulsive disorder (OCD) over the two-year of pharmacological treatment. Methods : The thirty-three OCD patients and thirteen normal subjects were administered the neuropsychological tests and clinical evaluations twice (at the baseline and two-year). Results : In spite of the two-year treatment, the accuracy of delayed recall on the Rey-Osterrieth Complex Figure Tests (RCFT), the numbers of responses on the category and letter test of Controlled Oral Word Association Test (COWA), the response time on the Trail Making Test part A (TMT-A) remained significantly impaired in the OCD patients compared with the normal controls. Conclusion : These findings suggest that the cognitive dysfunctions such as visuospatial memory and verbal fluency might be the underlying persisting neuropathophysiology of OCD.

Persistent cognitive dysfunction in patients with obsessive-compulsive disorder: A naturalistic study

ROH, KYU SIK,SHIN, MIN SUP,KIM, MYUNG-SUN,HA, TAE-HYUN,SHIN, YONG-WOOK,LEE, KYUNG JIN,KWON, JUN SOO Blackwell Science Pty 2005 Psychiatry and clinical neurosciences Vol.59 No.5

<P>Abstract </P><P>The purpose of the present study was to investigate the changes in the cognitive dysfunctions of patients with obsessive-compulsive disorder (OCD) over a 1-year period of pharmacological treatment. Twenty-one OCD patients and 20 normal subjects underwent neuropsychological tests and clinical evaluations on three separate occasions (baseline, 4 months, and 1 year after the start of medications). OCD patients continued to show significant impairments in the following cognitive measures compared with the normal controls: accuracy of immediate and delayed recall on the Rey-Osterrieth complex figure tests, the numbers of responses on the category fluency test, the response time on the trail making test – part A, and the number of perseverative response and perseverative errors on the Wisconsin card sorting test. The findings in this study suggested that impaired performance on cognitive domains, such as visuospatial memory and verbal fluency may underline the pathology of OCD.</P>

Guidelines for Mobile Laboratories for Molecular Diagnostic Testing of COVID-19

Roh Kyoung Ho,Hong Ki Ho,Nam Myung-Hyun,Kim Taek Soo,Seong Moon-Woo,이진경,Bae Sookyoung,Huh Hee Jae,Ahn Jeong-Yeal,Lim Jinsook,Kim Gab Jung,Park Jae Sun,Kim Hyun Yeong,Yoo Cheon Kwon,Lee Hyukmin 대한진단검사의학회 2022 Annals of Laboratory Medicine Vol.42 No.5

With the rapid spread of the coronavirus disease (COVID-19), the need for rapid testing and diagnosis and consequently, the demand for mobile laboratories have increased. Despite this need, there are no clear guidelines for the operation, maintenance, or quality control of mobile laboratories. We provide guidelines for the operation, management, and quality control of mobile laboratories, and specifically for the implementation and execution of COVID-19 molecular diagnostic testing. These practical guidelines are primarily based on expert opinions and a laboratory accreditation inspection checklist. The scope of these guidelines includes the facility, preoperative evaluation, PCR testing, internal and external quality control, sample handling, reporting, laboratory personnel, biosafety level, and laboratory safety management. These guidelines are useful for the maintenance and operation of mobile laboratories not only in normal circumstances but also during public health crises and emergencies.

중환자 가족의 돌봄 경험에 관한 연구

노은선,김경희,권혜진 성인간호학회 1997 성인간호학회지 Vol.9 No.2

The purpose of this study is to build up the foundation to prepare the effective nursing intervention devices for the seriously ill patient's families nursing through the nurse understanding of the experiences of the seriously ill patient's families in the field by setting up grounded theory. In this study, the subjects is the 6 famillies members of ICU patients, who were being cared in university hospital and the data were collected from 4.15 to 5, 1996 by the recording and transcring the interview. The intervention lastd from 2 hours to 2 and a half hours. The data were analyzed in the frame-work of grounded theory as mapped out by Strauss & Corbin. The core category in the analysis of the experiences of the familes of the seriouly ill patients was the process of setting the "distress". In the process of dats analysis, the categories were 19 conceptions-'serious', 'bad', 'fear', 'press', 'heartburn', 'impatient', 'insufficient', 'change of patients's status', 'economic ability', 'familly relationship', 'willed power', 'request', 'direct caring', 'passive effort', 'control', 'receive', 'tired', 'blame'. These categories were again grouped into 12 categories, including 'exigency', 'overwhelming', 'worry', 'change of status', 'economic ability', 'relationship', 'caring will', 'active caring', 'passive response', 'accept', 'exhaustion','blame'. In the above mentioned categories, 'overwhelming' and 'worry' were categorized into the "distress!". On the basis of the patterns that have emerged on process of data analysis, the five below were confirmed. (1) When the patient's status is worse and economic ability is bad and the family relation to the patient is close and the distress is expressed with active caring willness is strong, the distress is expressed with active caring and brings about accept and blame. (2) When the family relation to the patient is distant and the distress decrease and the subjects's caring willness is weak, the distress is expressed with passive response and brings about accept and exhaustion in spite of the patient's status is worse and bad economic ability. (3) When the patient's status is worse and economic ability is bad and the family relation to the patient is close and the distress increase, the subject's caring willness is strong, the distress is expressd with passive response and brings about accept and exhausion. (4) When the patient's status is improve and economic ability is good and the distress decrease and the subject's caring willing is strong, the distress is expressed with active caring and brings about accept and blame in spite of the family relation to the patient is close. (5) When the patient's status isn improve and economic ability is bad and the family relation to the patient is close and the distress increase, the subject's caring willness is strong, the distress is expressed with active caring and brings about accept and blame.

Premixed TiC–Ni composite powder prepared by mechanical milling of Ti–Ni alloy/graphite mixture and subsequent heat treatment

Kwon, Hanjung,Kim, Jiwoong,Jung, Sun-A,Suh, Chang-Yul,Kil, Dae-Sup,Roh, Ki-Min,Kim, Wonbaek,Lim, Jae-Won Elsevier 2014 Powder technology Vol.253 No.-

<P><B>Abstract</B></P> <P>The non-equilibrium (Ti,Ni)C solid-solution phase was prepared by mechanical milling of a Ti–Ni alloy/graphite mixture. The formation of the non-equilibrium (Ti,Ni)C solid solution was confirmed by X-ray diffraction. The (Ti,Ni)C solid-solution phase was found to decompose into TiC and finely dispersed Ni during the heat treatment in vacuum obviously due to the thermal instability of the non-equilibrium phase. The instability of the (Ti,Ni)C phase was clearly demonstrated by the consideration on the Gibbs free energy of formation of the phase. This new method allows the production of premixed TiC–Ni composite powder having a fine and uniform composition which may provide enhanced properties over the conventionally mixed TiC–Ni powder.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Gibbs free energies of formation of (Ti,Ni)C were obtained from first-principles calculations. </LI> <LI> Thermodynamic instability and decomposition of the (Ti,Ni)C phase were investigated. </LI> <LI> (Ti,Ni)C phase was formed by mechanically alloying Ti-Ni alloy and graphite. </LI> <LI> TiC-Ni powder with Ni was obtained by decomposing the (Ti,Ni)C phase. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>