• Title/Summary/Keyword: $T_2$ contrast

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Examining the Effects of Trained Peer Feedback on EFL Students' Writing

  • Kim, Bo-Ram
    • English Language & Literature Teaching
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    • v.15 no.2
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    • pp.151-168
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    • 2009
  • The present study investigates the impact of trained peer feedback on the quantity and quality of revisions made by EFL students at a low-intermediate level. Peer review training was carried out in experimental group through four in-class training sessions and four peer dyad-instructor conferences after class. Students' $1^{st}$ drafts with written peer feedback and revised drafts prior to and post training were collected and analyzed. Results reveal that after training the students produced more revisions in response to their peer comments (96% of total revisions) and those revisions were counted as enhanced in quality (93% of peer-triggered revisions). In contrast, the results of paired t-test within control group indicate that there was no significant difference between two data collected from week 3 and week 16 (t = -.57, df =19, p = .577 at p < .05). The findings suggest that training as an ongoing process of teacher intervention contributes to effectiveness of the peer feedback activity. The study provides pedagogical implications for how to structure and implement peer review training for the sake of its direct strength in an EFL writing class.

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Clinical Application of Functional MRI : Motor Cortex Activities by Acupuncture

  • Choe, Bo-Young
    • Journal of the Korean Magnetic Resonance Society
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    • v.6 no.2
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    • pp.89-93
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    • 2002
  • We report a preliminary fMRI evidence of modulation of somatomotor areas by acupuncture in GB34 acupoint. GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MR scanner, functional MR imaging was performed in five normal volunteers in two stimulation paradigms; acupuncture manipulation on GB34 and sham points. Group analysis form five individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6% whereas very few areas were activated when sham stimulation is given. Our results suggest that acupuncture fMRI study can be safely conducted in 3T environment and stimulation in GB34 modulate the cortical activities of the somatomotor area in human.

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Magnetic resonance imaging features of the biceps tendon rupture in a Labrador retriever dog

  • Cho, Hyunju;Choi, Hojung;Lee, Youngwon
    • Korean Journal of Veterinary Research
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    • v.60 no.4
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    • pp.233-236
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    • 2020
  • A five-year-old spayed female Labrador retriever presented with right forelimb lameness one day earlier. Radiographs and computed tomography of the right shoulder joint revealed conspicuous enthesophytes, bone cyst, and bone fragment at the intertubercular groove. Magnetic resonance imaging showed a loss of continuity of the biceps tendon and inhomogeneous hyperintense signal of the surrounding soft tissue and moderate synovial fluid on T2- and proton density-weighted images with contrast enhancement on the postcontrast T1-weighted images. The dog was diagnosed with tenosynovitis and biceps tendon rupture with osteoarthritis based on a comprehensive evaluation of the computed tomography and magnetic resonance imaging features.

Superconductivty and magnetic properties of $(Ru_{1-x}Nb_x)Sr_2(Sm_{1.4}Ce_{0.6})Cu_2O_z$

  • Lee, H.K.;Bae, S.M.;Lee, J.M.
    • Progress in Superconductivity and Cryogenics
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    • v.15 no.3
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    • pp.1-4
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    • 2013
  • We investigated the effect of Nb substitution for Ru on the structural and magnetic properties of $(Ru_{1-x}Nb_x)\;Sr_2(Sm_{1.4}Ce_{0.6})Cu_2O_z$ Samples. X-ray diffraction measurements indicated that nearly single-phase samples are formed in the range from x = 0 to 1.0. The superconducting transition temperature determined from the inflection in the field-cooled magnetic susceptibility decreased only slightly from $T_c$ = 25 K for x = 0 to $T_c$ = 22 K for x = 1.0, in consistent with the change in room temperature thermopower of the samples. However, the Nb substitution for Ru above x = 0.25 significantly suppressed the weak ferromagnetic component of the field-cooled magnetic susceptibility. It was also found that the Nb substitution for Ru results in an enhanced diamagnetic susceptibility with Nb content above x = 0.5 in both zero field-cooled and field-cooled magnetization measurements, in contrast to the behavior of the samples with $x{\leq}0.5$ in which the diamagnetic susceptibility decreases as the Nb content increases.

A Kinetic Study on Aminolysis of t-Butyl 4-Pyridyl Carbonate and Related Compounds: Effect of Leaving and Nonleaving Groups on Reaction Mechanism

  • Kang, Ji-Sun;Lee, Jae-In;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.2971-2975
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    • 2012
  • Second-order rate constants $k_N$ have been measured spectrophotometrically for nucleophilic substitution reactions of t-butyl 4-pyridyl carbonate 8 with a series of alicyclic secondary amines in $H_2O$ at $25.0{\pm}0.1^{\circ}C$. The Br${\emptyset}$nsted-type plot for the reactions of 8 is linear with ${\beta}_{nuc}$ = 0.84. The ${\beta}_{nuc}$ value obtained for the reactions of 8 is much larger than that reported for the corresponding reactions of t-butyl 2-pyridyl carbonate 6 (i.e., ${\beta}_{nuc}$ = 0.44), which was proposed to proceed through a forced concerted mechanism. Thus, the aminolysis of 8 has been concluded to proceed through a stepwise mechanism with a zwitterionic tetrahedral intermediate $T^{\pm}$, in which expulsion of the leaving-group from $T^{\pm}$ occurs at the rate-determining step (RDS). In contrast, aminolysis of benzyl 4-pyridyl carbonate 7 has been reported to proceed through two intermediates, $T^{\pm}$ and its deprotonated form $T^-$ on the basis of the fact that the plots of pseudo-first-order rate constant $k_{obsd}$ vs. amine concentration curve upward. The current study has demonstrated convincingly that the nature of the leaving and nonleaving groups governs the reaction mechanism. The contrasting reaction mechanisms have been rationalized in terms of an intramolecular H-bonding interaction, steric acceleration, and steric inhibition.

Analyses of Security Consideration and Vulnerability based on Internet of Things (사물인터넷 기반의 시스템을 위한 보안 취약성 및 고려사항 분석)

  • Jang, Chang-hwan;Jo, Sung-ho;Lee, Jin-hyup;Kim, Jung-Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.491-494
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    • 2017
  • Recently, IoT has been supported by ICT technology with a variety of ICT powers. In May 2014, Information and Communication Strategy Committee announced the 'Basic plan for Internet of Things'. Also on Febuary 24 this SAME year, KISA(Korea Internet&Security Agency) provides many projects related to IoT, such as announcement of 'K-Global Project' for start-up and venture support related to IoT and ICT companies. In contrast to the various services of Internet of Things, when a connection is made between object-to-object or person-to-object wired and wireless networks, security threats have occurred in the process of communication. We analyzed these kinds of security threats related to Internet of things, and gave a consideration for requirement.

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S&T Collaboration in Developing Countries: Lessons from Brazilian Collaboration Activities with South Korea

  • Fink, Daniel;Hameed, Tahir;So, Minho;Kwon, Youngsun;Rho, Jae Jeung
    • STI Policy Review
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    • v.3 no.2
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    • pp.92-110
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    • 2012
  • An active policy role is suggested for collaboration that will enhance national level Science and Technology (S&T) capabilities. In contrast, some studies see a limited role of policy support for collaborative S&T research at the individual level (including research groups or institutional levels) due to their self-organizing nature. Two views on S&T collaboration look at different levels but existing research largely ignores the context of developing countries. This paper shows how S&T collaborations between Brazil and Korea have developed over the past two decades. The paper indicates the gaps between initiation and the actual establishment of collaborative research at national and individual levels, differences in the focus areas of research, differences in resources and project planning, and the nature of collaborations. Collaborative research activities at the national level were initiated before the individual level but activated later than the individual level; in addition, the focus areas of research were laid down earlier at the national level with individual collaborations focused on different areas. Project types remained different at each level (i.e. top-down and bottom-up) or with a slightly changing mix. This study suggests appropriate policy measures (such as the timely and effective information collection of activities at different levels and proactive coordination) that could reduce the gaps in the timing and alignment of research areas. This paper also alludes to an evolutionary model to develop S&T collaboration among developing countries.

Effects of Carbofuran and Compensation of Phenobarbital sodium in the NIH 3T3 Fibroblast and Rat Kidney (Carbofuran이 NIH 3T3섬유모세포와 흰쥐의 신장에 미치는 영향과 Phenobarbital sodium의 보상효과에 관한 연구)

  • 한두석;임요섭;한성수
    • Toxicological Research
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    • v.13 no.1_2
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    • pp.87-94
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    • 1997
  • This study was carried out to investigate toxicity of insecticide carbofuran and compensatory effects of phenobarbital sodium (PB) in vivo and in vitro. Sprague Dawley male rats were used as experimental animals and divided into carbofuran only administered group and simultaneous application group of carbofuran and PB. At 30 rain and 1, 3, 6, 12, 24, 48 and 96 hrs after each treatment, the animals were sacrificed by decapitation. Kidney were immediately removed, immersed in fixatives, and processed with routine method for light microscopic study. Paraffin sections were stained with H-E, PAM and PAS. $5.0\times 10^4$ cell/ml of NIH 3T3 fibroblast in each well of 24 multidish were cultured: After 24 hours, the cells were treated with solution of six groups; control group cultured in media only, carbofuran $MTT_50$ or $NR_50$ group cultured in the media containing carbofuran $MTT_50$ or $NR_50$ and four experimental groups cultured in the media containing carbofuran $NR_50$ plus various concentratins of PB. After the NIH 3T3 fibroblast of all groups were cultured in same condition for 48 hours, Tetrazolium MTT (MTT) and NR (neutral red) assay were performed to evaluate the cytotoxicity of cell organelles. Under the light microscope, atrophic change of renal corpuscles were frequently observed in 1 and 2 days after carbofuran treatment. The increase of the mesangium was apparent in 1 and 2 days after carbofuran treatment. Necrotic changes of the epithelium and loss of brush border of proximal tubules were most severe at 2 and 3 days after carbofuran treatment, respectively. In contrast, there were no evidences of the toxic effects on renal tissues at 48hrs in carbofuran-PB treated groups. Carbofuran $MTT_50$ and $NR_50$ were 78$\mu M$, 82.5$\mu M$ respectively. MTT and NR quantities were significantly increased in carbofuran-PB 100$\mu M$ treatment group and carbofuran-PB 100$\mu M$ treatment group. On the basis of these results, it is obvious that PB has compensatory effects against carbofuran toxicity.

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Survey on Self Care, Respiratory Difficulty, Sleep Impediment, Anxiety and Depression among Patients with Neuromuscular Disease dependent on Home Mechanical Ventilator (재가 가정용인공호흡기 적용 신경근육계 질환자의 호흡곤란, 수면장애, 불안 및 우울에 관한 연구)

  • Hwang, Moon Sook;Lee, Mi Kyung;Song, Jong Rye
    • Korean Journal of Adult Nursing
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    • v.28 no.5
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    • pp.595-606
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    • 2016
  • Purpose: This study aimed to investigate the influencing factors on self care, respiratory difficulty, sleep impediment, anxiety and depression among patients with neuromuscular disease who are dependent on Home Mechanical Ventilator (HMV). Methods: 157 patients were recruited through hospital based home nursing care departments and HMV rental centers. Data were collected by questionnaires. The analytic methods were n(%)/$M{\pm}SD$, $x^2$/t-test or ANOVA and multiple linear regression. Results: Patients with Amyotrophic lateral sclerosis were more likely to utilize HMV, had shorter periods of morbidity and the most extended daily use of HMV. As for medical equipment, they had ambu-bag (87.2%) and oxygenator (15.4%). Reports of respiratory difficulty and sleep impediment were low. There were no significant difference. In contrast, reported anxiety and depression were high and showed significant difference between non invasive HMV and invasive HMV. Anxiety contributes to respiratory difficulty (t=3.62, p=.002), sleep impediment (t=2.06, p=.042), and depression (t=7.24, p<.001). However, home nursing care exerts a positive influence in reducing anxiety (t=-2.73, p=.008). Conclusion: Anxiety contributes to respiratory difficulty, sleep impediment, and depression. However, those who use home nursing care reported less anxiety. Home nursing care positively impacts patients dependent on HMV as a practical service and available resource.

Distribution of Length Variation of the mtDNA 9-bp Motif in the Intergenic COII/tRNAX$^{Lys}$ Region in East Asian Populations

  • Han Jun Jin;Jeon Won Choi;Dong Jik Shin;Jung Min Kim;Wook Kim
    • Animal cells and systems
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    • v.3 no.4
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    • pp.393-397
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    • 1999
  • Length variations in human mitochondrial DNA (mtDNA) offer useful markers in the study of female aspects of human population history. One such length variation is a 9-bp deletion in the small noncoding segment located between the COII and Iysine tRNA genes (COII/tRNA/$^{Lys}$ intergenic region) which usually contain two tandemly arranged copies of a 9-bp sequence (ccccctcta) in human mtDNA. The mtDNA 9-bp deletion and polymorphic variants of expanded 9-bp repeat motif in the intergenic COII/tRNA$^{Lys}$ region have been found at varying frequencies among different human ethnic groups. We have examined the length variation of the mtDNA COII/tRNA$^{Lys}$ intergenic region from a total of 813 individuals in east Asian populations. The occurrence of the 9-bp deletion was found to be relatively homogeneous in northeast Asian populations (Chinese, 14.2%; Japanese, 14.3%: Koreans, 15.5%), with the exception of Mongolians (5.1%). In contrast, Indonesians (25.0%) and Vietnamese (23.2%) of the southeast Asian populations appeared to have relatively high frequencies of the 9-bp deletion. We identified the existence of a new expanded 9-bp repeat motif which likely resulted from a slipped mispairing insertion of six more cytosines in the intergenic COII$^{Lys}$ region. It was present at low frequencies in the Korean (2/349) and Japanese populations (2/147). Based on the results of this study, the Korean population may reflect a close genetic affinity with the Japanese and Chinese populations than the others surveyed east Asian populations.

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