• Phonetics and Speech Sciences
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• v.5 no.4
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• pp.201-207
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• 2013

This study is a follow-up study of Han and Kang (2013) and Kang and Han (2013) which examined cross-generational changes in the Korean vowels /o/ and /u/ using acoustic analyses of the vowel formants of these two vowels, their Euclidean distances and the overlap fraction values generated in SOAM 2D (Wassink, 2006). Their results showed an on-going approximation of /o/ and /u/, more evident in female speakers and non-initial vowels. However, these studies employed non-words in a frame sentence. To see the extent to which these two vowels are merged in real words in spontaneous speech, we conducted an acoustic analysis of the formants of /o/ and /u/ produced by two age groups of female speakers while reading a letter sample. The results demonstrate that 1) the younger speakers employed mostly F2 but not F1 differences in the production of /o/ and /u/; 2) the Euclidean distance of these two vowels was shorter in non-initial than initial position, but there was no difference in Euclidean distance between the two age groups (20's vs. 40-50's); 3) overall, /o/ and /u/ were more overlapped in non-initial than initial position, but in non-initial position, younger speakers showed more congested distribution of the vowels than in older speakers.

• Phonetics and Speech Sciences
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• v.5 no.2
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• pp.25-31
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• 2013

This study examined cross-generational changes in the vowel system of Seoul Korean. Acoustic analyses of the vowel formants of /o/ and /u/, and their Euclidean distances in the vowel space were undertaken to explore an on-going merger of these two vowels as proposed in previous acoustic studies and a phonological analysis by Chae (1999). A robust cross-generational change of /o/ and /u/ was found, more evident for female speakers than for male speakers. For female speakers, with each successive generation, /o/ became increasingly approximated with /u/, regardless of the syllable positions that the target vowels were posited, whereas the cross-generational differences in the Euclidean distances were only shown in the second syllable position for the male speakers. These results demonstrate that 1) women are more advanced than men in the on-going approximation of /o/ and /u/; 2) the approximation of /o/ and /u/ is common in the non-initial position. Taken together, the merger of /o/ and /u/ appears to be in progress in Seoul Korean.

• Molecules and Cells
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• v.26 no.6
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• pp.590-594
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• 2008

brc-2, an ortholog of BRCA2 in Caenorhabditis elegans, is essential in the maintenance of genetic integrity. In C. elegans, cellular location correlates with meiotic progression, and transgene-induced cosuppression is observed in the germ line but not in somatic cells. We used these unique features to dissect the role of brc-2 in the germ line from that in somatic cells. In situ hybridization of wild type animals revealed that brc-2 gene expression was higher in oocytes than in other germline cells, and was barely detectable in mitotic cells. In contrast, germ cells containing multicopies of the brc-2 transgene showed no significant in situ hybridization signal at any oogenesis stage, confirming that brc-2 expression was functionally cosuppressed in the transgenic germ line. RAD-51 foci formation in response to DNA damage was abrogated in brc-2-cosuppressed germ cells, whereas wild-type germ cells showed strong RAD-51 foci formation. These germ cells exhibited massive chromosome fragmentation and decompaction instead of six bivalent chromosomes in diakinesis. Accordingly, lethality was observed after the early stage of germline development. These results suggest that brc-2 plays essential roles in chromosome integrity in early prophase, and therefore is crucial in meiotic progression and embryonic survival.

• Molecules and Cells
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• v.38 no.3
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• pp.251-258
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• 2015

Germline mutations in the breast cancer type 2 susceptibility gene (BRCA2) are linked to familial breast cancer and the progressive bone marrow failure syndrome Fanconi anaemia. Established Brca2 mouse knockout models show embryonic lethality, but those with a truncating mutation at the C-terminus survive to birth and develop thymic lymphoma at an early age. To overcome early lethality and investigate the function of BRCA2, we used T cell-specific conditional Brca2 knockout mice, which were previously shown to develop thymic lymphoma at a low penetrance. In the current study we showed that the number of peripheral T cells, particularly na$\ddot{i}$ve pools, drastically declined with age. This decline was primarily ascribed to improper peripheral maintenance. Furthermore, heterozygous mice with one wild-type Brca2 allele manifested reduced T cell numbers, suggesting that Brca2 haploinsufficiency might also result in T cell loss. Our study reveals molecular events occurring in Brca2-deficient T cells and suggests that both heterozygous and homozygous Brca2 mutation may lead to dysfunction in T cell populations.

• Progress in Medical Physics
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• v.15 no.3
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• pp.128-133
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• 2004

The fMRI response of the somatosensory cortex was investigated with vibrotactile stimulation. Three different frequencies of 8, 15, or 25 Hz were applied in order to mainly focus on the hemodynamic response of Meissner corpuscles sensitive to frequencies of 5-40 Hz. A closed-system, pneumatically-driven, rubber diaphragm was fabricated that overcame many of the limitations of existing vibrotactile devices and produced robust sensory cortex activation in an fMRI experiment. Increasing frequency vs. activation area was analyzed in terms of signal percent change and number of pixels. Our preliminary results indicated that the distribution of the signal percentage change widened and more activated pixels were obtained with higher frequencies.

• Korean Journal of Optics and Photonics
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• v.26 no.4
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• pp.187-194
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• 2015

A system of infrared camera optics with wide field of view and anamorphic lenses is proposed, and its validity verified through manufacture. The infrared camera produced provides a wide field of view of over 100 degrees in the horizontal direction, and an even greater magnification in the vertical direction. As a result, the system can have a wider surveillance range and improved detection ability at the same time. In addition, a new optomechanical automatic athermalization mechanism is proposed and applied to the infrared camera. Its performance and utility is proved through testing.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.9_10 s.146
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• pp.1295-1305
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• 2005

The study was based on a three-stage, non-repetitive factorial experiment in which chemical-rotted kenaf fibers were treated separately with hydrogen peroxide concentrations of $0.5\%,\;1\%\;and\;2\%$, with pH solutions of 7, 9 and 11, and treatment times of 30, 60 and 90 minutes. Under optimal conditions, the study was conducted to determine the bleaching efficiency by the addition of chelators, penetrants and surfactants. The bleaching effects on the kenaf fibers were high in high hydrogen peroxide concentration, high in alkali solution pH, low in long treatment time. The optimal level of hydrogen peroxide on bleaching effects were at $2\%$ hydrogen peroxide concentration, with pH of 11 and treatment time of 60 minutes. Under the conditions of $2\%$ hydrogen peroxide concentration, pH 11 and treatment time of 60 minutes, the addition of chelator: Sodim Pyrophosphate(SP), Citric Acid(CA) made the bleaching effects of the kenaf fibers high.

• MALSORI
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• no.40
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• pp.1-12
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• 2000

This paper investigated how $/\int/$ in English and German is perceived and interpreted in the loanwords in Korean. $/\int/$ in these languages does not show one-to-one correspondence in Korean: $/\int/$ in the coda position in English and German is perceived as [swi] in Korean while $/\int/$ in the onset position is perceived as [syu]. This paper examined phonetic characteristics of $/\int/$ in English and German through its acoustic analysis and attempted to figure out which factor could explain this surface distribution of [swi] and [syu]; phonological (onset vs. coda) or phonetic (coarticulation) factor. Two acoustic features of $/\int/$ in English and German were examined: duration and energy Peak frequency of the frication noise. German $/\int/$ Perceived as [swi] in Korean showed higher energy Peak frequency and longer duration than that perceived as [syu] in Korean. English iii perceived as [swi] also showed longer duration than that Perceived as [syu] in Korean but energy Peak frequency showed different behavior. English $/\int/$ showed coarticulation with the preceding vowel rather than being affected by its position in the syllable in English. This paper concludes that 1)Phonetic characteristics used are duration and energy Peak frequency of its frication noise when $/\int/$ in English and German are adopted in Korean, 2)duration is used prior to energy peak frequency, which can be used as an enhancing feature.

• Child Health Nursing Research
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• v.23 no.4
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• pp.494-504
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• 2017

Purpose: The aim of this study was to analyze Neonatal Intensive Care Unit nurses' behaviors while soothing newborns with bronchopulmonary dysplasia. Methods: An observational study was used to assess nurses' soothing behaviors. Data were collected from September, 2012 to March, 2013 using an audio-video recording system. Participants were eight babies and 12 nurses caring for those babies. After obtaining parental permission, the overall process of each episode from nurses' engagement in soothing to the end of soothing was recorded. Then a researcher interviewed each participating nurse. Data from 18 episodes were transcribed as verbal and nonverbal nursing behaviors and then categorized by two researchers. Results: There were 177 observed soothing behaviors which were classified with the five sensory-based categories (tactile, oral, visual, auditory, vestibular). Most frequently observed soothing behavior was 'Gently talking' followed by 'Removing irritant', and 'Providing non-nutritive sucking'. Nurses' perceived soothing behaviors were similar to the observed soothing behaviors except for 'Gently talking'. Conclusion: Nurses used diverse and mixed soothing behaviors as well as recognizing those behaviors as essential nursing skills. Nurses' soothing behaviors identified in this study can be used to comfort babies and to enhance their developmental potential in accordance with individual characterstics or cues.

• The Research Journal of the Costume Culture
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• v.22 no.5
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• pp.702-711
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• 2014

This study was performed to investigate the hand size growth of Korean adolescents boys. Subjects were between 14 and 19 years (n=352). We collected the right hand size data of 19 measurements from each subject using 3D hand scanner. The total 26 hand measurements were analyzed including seven calculated measurements. Subjects were divided into three age groups (early, middle and late). Their hand size were compared. The results showed that all hand length measurements were significantly difference among age groups. Adolescent boys hands were sharply grown at age 16 years old. The hand dimensions of middle age group were compared with twenties men (n=215). There were significant differences between two groups. The middle age adolescents' hands were shorter and thicker than twenties men. Subjects were also divided by weight and height. Weight and height was closely related to hand size. The heavier and taller subjects had the thicker hand. Their fingers were longer than others. The adolescent boys and twenties men who were taller than the twenties' average height (173.4cm) were compared. Twenties men's hands were longer and thinner than that of adolescent boys. These results imply that the male adolescent hands grow short and thick in the adolescent period. Fingers continuously grow up as a long and thin shape after adolescent period.