• 제목/요약/키워드: Silver College

검색결과 543건 처리시간 0.028초

Zinc Sulfide-selenium X-ray Detector for Digital Radiography

  • Park, Ji-Koon;Kang, Sang-Sik;Kim, Jae-Hyung;Mun, Chi-Woong;Nam, Sang-Hee
    • Transactions on Electrical and Electronic Materials
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    • 제3권4호
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    • pp.16-20
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    • 2002
  • The high bias voltage associated with the thick layer (typically 500-1000 ㎛) of selenium required to have an acceptable x-ray absorption in radiography and fluoroscopy applications may have some practical inconvenience. A hybrid x-ray detector with zinc sulfide-amorphous selenium structure has been developed to improve the x-ray sensitivity of a a-Se based flat-panel digital imaging detector. Photoluminescence(PL) characteristic of a ZnS:Ag phosphor layer showed a light emission peak centered at about 450 nm, which matches the sensitivity spectrum of selenium. The dark current of the hybrid detector showed similar characteristics with that of a a-Se detector. The x-ray sensitivity of hybrid and a-Se x-ray detector was 345 pC/㎠/mR and 295 pC/㎠/mR at an applied voltage of 10 V/㎛, respectively. The purpose of this study was to evaluate the pertinence of a solution using a thin selenium layer, as a photosensitive converter, with a thick coating of silver doped zinc sulfide phosphor.

측면수직보조전계에 의한 전기영동전착 기술 (Electrophoretic Deposition Technique by Vertical Lateral Assisted Field)

  • 소대화;전용우;박정철;번점국
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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    • pp.82-85
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    • 2003
  • This dissertation describes an optimization method for fabricating thick films with superconducting YBCO powders by electrophoresis technique. The lateral alternating applied voltage caused to shake the superconducting powder vertically to the deposition field during the process of the oriented deposition so that it was deposited along the c-axis on the silver tape with shaky-aligned EPD. As the result, the optimized thin film fabrication method was obtained to get more dense and uniform surface morphology as well as the improved critical current density. For commercial utilization and efficiency, in this dissertation, alternating voltage of 25-120 V/cm in frequency of 60Hz was proposed to apply it as a subsidiary source for shaky-flow deposition so that the fabricated thin film showed uniform surface morphology with less voids and cracks and $T_{c.zero}$ of 90 K and the critical current density of $3419A/cm^2$.

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인공타액에서 아말감 초기부식에 대한 실험적 연구 (AN EXPERIMENTAL STUDY ON THE INITIAL AMALGAM CORROSION IN ARTIFICIAL SALIVA)

  • 김미자;이명종
    • Restorative Dentistry and Endodontics
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    • 제17권2호
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    • pp.287-306
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    • 1992
  • The amounts of copper, mercury, silver, tin, and zinc released from conventional, dispersed phase and spherical high copper content amalgam immersed in artificial saliva soln. for periods of 2 hours, 1 day, 7 days, 30 days has been measured using Neutron Activation analysis and Atomic Absorption Spectrophotometry. The second electron image and EDX of the surface of samples immersed in artificial saliva were observed using SEM. The following results were obtained. 1. The dispersed non-$\gamma_2$ amalgam released more Hg, Ag than the $\gamma_2$-amalgams. Later a decrease of the release rate could be observed. 2. The dispersed high copper amalgam released more copper than low-copper amalgam and the release rate was decreased with time. But the amounts of copper released from Tytin increased with time. 3. Zinc was released all the experiment time. 4. EDAX showed that surface was composed of Ca,P, Sn, Ag, Zn, and Cu, but C1 was not detected. 5. The discontinued destructed surface was observed from the polished amalgam surface. High copper amalgam was destructed more than low copper amalgam.

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Geographic Variation of Granulilittorina exigua (Littorinidae, Gastropoda) in Korea Based on the Mitochondrial Cytochrome b Gene Sequence

  • Song, Jun-Im;Suh, Jae-Hwa;Kim, Sook-Jung
    • Animal cells and systems
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    • 제4권3호
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    • pp.267-272
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    • 2000
  • Partial sequence of the mitochondrial cytochrome b gene was analyzed to investigate genetic variation from 10 geographic populations of Granulilittorina exigua in Korea. The sequence of 282 base pairs was determined by PCR-directed silver sequencing method. The sequences of two species within the genus Littorina reserved in NIH blast search were utilized to determine geographic variations of species referred. The levels of mtDNA sequence differences were 0.00-2.54% within populations and 0.71-4.43% between populations. There were four amino acid differences between representative species of the genera Granulilittorina and Littorina, but no differences within populations of the genus Granulilittorina. The UPGMA and the N-J trees based on Tamura-Nei genetic distance matrix were constructed, which showed that the genus Granulilittorina was divided into three groups such as eastern (even exception for Tokdo population), southern, and western regional populations. The degrees of genetic divergence within populations of each group were p=0.021, p=0.019, and p=0.018, respectively. The divergence between the eastern and southern populations was p=0.032, showing closer relationship than with the western populations (p=0.052). Based on the diverged time estimation, the eastern and southern populations of Granulilittorina exigua in Korea diverged from the western populations about 2.1 MYBP, and the eastern and southern populations diverged from each other about 1.3 MYBP.

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뇌졸중 환자가족의 가족부담감과 건강관련 삶의 질 (Caregiver Burden and Health-related Quality of Life Among Stroke Caregivers)

  • 김은영;신은영;김윤미
    • 한국보건간호학회지
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    • 제18권1호
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    • pp.5-13
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    • 2004
  • Purpose: This study was performed to examine the relationship between caregiver burden and health-related quality of life (HRQOL) in family caregivers of stroke patients in the community. Methods: Subjects were 33 stroke patients who had a experience of hospitalization during last 1 year and their family. Data were obtained from personal interview by nursing students in October, 2003. We assessed the functional status of stroke patients, caregiver burden and the HRQOL of caregivers using SF-8. Results: A higher subjective burden was related to dependent functional status of patients than independent(P<.01). The independent cognitive function of stroke patients and good health of caregivers were related to high HRQOL of caregivers. PCS and MCS of HRQOL were negatively correlated to subjective burden, -.34(p<.01) and -.37(p<.05). Conclusion: We founded functional status of stroke patients. caregiver burden and HRQOL of caregivers were related to each other. To improve the HRQOL of caregiver, decreasing burden of caregivers and the functional status improvement of stroke patients must be considered.

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기억강화프로그램이 노인의 인지기능, 자아존중감과 기억수행에 미치는 영향 (Influence of Memory Intensive Training Program on Cognitive Function, Memory Performance, and Self-Esteem in Elderly People)

  • 정명숙;김정화
    • 재활간호학회지
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    • 제13권2호
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    • pp.161-170
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    • 2010
  • Purpose: This study was to confirm the influence of memory intensive training program on the elderly people's cognitive function, memory performance, and self-esteem. Method: Using a quasi-experimental or experimental design, 60 elderly aged over 60 years randomly assigned the experimental and control groups completed pretest-post evaluation. The experimental group participated in the memory intensive training program was offered to the participants in the experimental group for three weeks (2times/week). The t-test and $X^2$-test using SAS program. Results: 1) The cognitive function was significantly higher in the experimental group compared to that in the control group (t=3.26, p=.002). 2) The memory performance that included immediate word recall tasks, word recognition tasks and delayed word recall tasks was significantly higher in the experimental group than in the control group (t=5.30, p<.001). The experimental group showed significantly higher scores for memory performance than the control group (t=5.30, p<.001). 3) The self-esteem was higher in the experimental group than in the control group, but there was no significant difference between the two groups (t=1.94, p=.058). Conclusion: The Memory Intensive Training Program could be an effective intervention for improving cognitive function, and memory performance of the elderly people.

수면장애에 관한 동서의학적 고찰 및 국내 간호연구 분석 (A Bibliographic Study about Comparison of Eastern-Western Medicine on Sleep Disturbances and Trend Analysis of Korean Nursing Research)

  • 전상희;장정미
    • 동서간호학연구지
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    • 제15권1호
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    • pp.43-53
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    • 2009
  • Purpose: This study is to summarize of Western-Eastern books and articles on sleep disturbances and to analyze the trends of nursing research in Korea. Methods: The Western-Eastern books and articles on sleep disturbances were comprehensively reviewed. The 70 articles published from 1981-2008 of Korean nursing research about sleep disturbances were reviewed using a structured form. Results: In Oriental medicine, the main cause of sleep disorder is unbalance of Yin and Yang, the treatments are herb therapy, acupuncture, moxibustion, psychotherapy, sleep hygiene, etc. In Western medicine, the International Classification of Sleep disorder is dyssomnia, parasomnia, mental/neurologic or other medical disorders, proposed sleep disorder and the treatments are pharmacotherapy, cure treatment of sleep hygiene, cause, behavior and perception. The number of nursing research and experimental study about sleep disorder in Korea is increasing. The most common subjects were hospitalized patients and the elderly, Of the 34 experimental studies, foot reflexology was the most commonly used as a nursing intervention. Conclusions: Nurses should concern more on patients' or clients' sleep disturbances to increase their quality of life. This literature study is useful for the access to effective nursing intervention for sleep disturbances.

Cytomegalovirus retinitis with panretinal occlusive vasculopathy concealed by hypertensive uveitis: a case report

  • Seongyong Jeong
    • Journal of Yeungnam Medical Science
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    • 제41권4호
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    • pp.300-305
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    • 2024
  • Cytomegalovirus (CMV) retinitis is a rare disease, and overlapping manifestations involving the anterior segment are extremely uncommon. We report a patient who initially presented with persistent corneal edema and was later diagnosed with CMV retinitis. A 72-year-old man with uncontrolled intraocular pressure (IOP) in his right eye visited a tertiary hospital. At initial presentation, the IOP was 36 mmHg and the fundus was not clear due to corneal edema. Spectral domain optical coherence tomography revealed paracentral acute middle maculopathy (PAMM). Panretinal obstructive vasculopathy was observed on ultra-widefield fluorescein angiography. Three weeks later, trabeculectomy was performed to resolve the persistently high IOP. Once corneal edema improved, a white patch-like peripheral lesion and silver wire-like retinal vasculature were observed. Polymerase chain reaction of the aqueous humor was positive for CMV. Oral valganciclovir and intravitreal ganciclovir were administered as antiviral therapies. Despite treatment for 4 months, the final visual acuity was no light perception, with persistent corneal edema and neovascularization of the iris. We describe a rare case of the simultaneous occurrence of hypertensive uveitis and CMV retinitis. The presence of PAMM could be an initial identifiable sign of CMV retinitis, even in the presence of media opacity.

Social Network Characteristics and Body Mass Index in an Elderly Korean Population

  • Lee, Won Joon;Youm, Yoosik;Rhee, Yumie;Park, Yeong-Ran;Chu, Sang Hui;Kim, Hyeon Chang
    • Journal of Preventive Medicine and Public Health
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    • 제46권6호
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    • pp.336-345
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    • 2013
  • Objectives: Research has shown that obesity appears to spread through social ties. However, the association between other characteristics of social networks and obesity is unclear. This study aimed to identify the association between social network characteristics and body mass index (BMI, $kg/m^2$) in an elderly Korean population. Methods: This cross-sectional study analyzed data from 657 Koreans (273 men, 384 women) aged 60 years or older who participated in the Korean Social Life, Health, and Aging Project. Network size is a count of the number of friends. Density of communication network is the number of connections in the social network reported as a fraction of the total links possible in the personal (ego-centric) network. Average frequency of communication (or meeting) measures how often network members communicate (or meet) each other. The association of each social network measure with BMI was investigated by multiple linear regression analysis. Results: After adjusting for potential confounders, the men with lower density (<0.71) and higher network size (4-6) had the higher BMI (${\beta}$=1.089, p=0.037) compared to the men with higher density (>0.83) and lower size (1-2), but not in the women (p=0.393). The lowest tertile of communication frequency was associated with higher BMI in the women (${\beta}$=0.885, p=0.049), but not in the men (p=0.140). Conclusions: Our study suggests that social network structure (network size and density) and activation (communication frequency and meeting frequency) are associated with obesity among the elderly. There may also be gender differences in this association.

Optimization of Agrobacterium-mediated transformation procedure for grapevine 'Kyoho' with carrot antifreeze protein gene

  • Shin, Hye Young;Kim, Gi Hoon;Kang, Sang Jae;Han, Jeung-Sul;Choi, Cheol
    • Journal of Plant Biotechnology
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    • 제44권4호
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    • pp.388-393
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    • 2017
  • We report an Agrobacterium-mediated transformation procedure optimized for 'Kyoho' that is a major table grapevine cultivar in Korea, and its transgenic plants with antifreeze protein gene of carrot (DcAFP). The full length of DcAFP coding region in accordance with the previous report was isolated from young leaves of carrot and recombined into a plant transformation vector. Ethylene inhibitors such as silver nitrate and aminoethoxyvinylglycin (AVG) supplemented in a co-cultivation medium distinctly increased frequency of shoot regeneration when explants were sub-cultured in a selection medium: particularly ten-fold higher in treatment with 0.1 mg/L AVG than one without ethylene inhibitor. Among various antibiotics and their concentrations, the combination of 150 mg/L cefotaxime plus 150 mg/L $Clavamox^{TM}$ was selected for elimination of Agrobacterium cells in addition to minimization of adverse effect on shoot regeneration, while 50 mg/L kanamycin monosulfate effectively suppressed regeneration of non-transgenic shoots. Applying the elucidated culture condition, we finally obtained a total of 5 transgenic 'Kyoho' plantlets with DcAFP, of which integration with the grapevine genome and transcription was confirmed by nucleic acid analyses.