• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.502-506
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• 1996

Tc-99m myocardial perfusion agents such as Tc-99m sestamibi or Tc-99m tetrofosmin has advantages over T1-201 for myocardial perfusion scan fuck as low attenuation and easy availability. However, Tc-99m agents do not redistribute so they need to be given T times, namely after stress and at rest. To evaluate whether rest image is needed in patients showing normal stress image, 43 patients who underwent both myocardial perfusion scan and coronary angiography and showed normal stress images were evaluated. Findings of rest images of them were evaluated whether they change the diagnosis or treatment plans. Among 43 patients who showed normal stress myocardial perfusion imaging, 31 (72.1%) showed no additional informations. However, among 5 patients with vasospastic angina 4 (80%) showed abnormal rest images in spite of normal stress images. So, when vasospastic angina is suspected clinically, rest image could be helpful in identifying patients with coronary vasospasm. In conclusion, rest myocardial perfusion images were not helpful in 72.1 % of patients with angina when stress images were normal. In only exception was those with vasospastic angina.

• Journal of Mechanical Science and Technology
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• v.19 no.11
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• pp.1967-1974
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• 2005

The subsurface stress field caused by both normal loads and tangential loads has been evaluated using the rectangular patch solution. The effect of tangential loading on the subsurface stress field has been investigated in detail for both the cylinder-on-cylinder contact and a spur gear teeth contact. For the cylinder-on-cylinder contact, the subsurface stress fields are moved more to the direction of tangential loads and the positions where the maximum stress occur are getting closer to the surface with the increasing tangential loads. The subsurface stress fields of the gear teeth contact are expanded more widely to the direction of tangential loads with the increasing tangential loads. The friction coefficient of a gear teeth contact is low because they are operated in a lubricated condition, and therefore surface tractions in the EHL condition hardly affect on the subsurface stress field.

• The Journal of Korean Medicine
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• v.28 no.3 s.71
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• pp.183-196
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• 2007

Objective : This study was conducted in order to find the effects of Gammaekdaejo-tang (Ganmaidazao-tang, GDT) by subjecting rats to immobilization stress, thereby inducing depression, anxiety and acquisition-retention defects. Method : Rats treated with normal saline, GDT 200mg/kg and GDT 400mg/kg were subjected to stress by immobilization. Afterwards, behavior changes were observed by elevated plus maze test, acquisition test and retention test in the Morris water maze. The results were obtained by immunohistochemically measuring stress hormone (corticosteroid) levels in the blood. Results and Conclusions : 1. The open arm test in the elevated plus maze showed that compared with the normal group, the time spent decreased in the control group and increased in the GDT 400mg/kg group. 2. The locomotor activity test in the elevated plus maze revealed that the control group showed significant activity decrease compared with the normal group but significant increase in the GDT 400mg/kg group. 3. The acquisition test in the Morris water maze showed that the acquisitive ability of the control group significantly deteriorated on the 3rd and 4th day compared with the normal group, but improved significantly in the GDT 200mg/kg and GDT 400mg/kg groups. 4. The retention test on the 7th day in the Morris water maze revealed that the retentive ability of the control group significantly deteriorated compared with the normal group, but the retentive ability of the GDT 400mg/kg group significantly improved. 5. The blood levels of corticosteroid in the control group increased significantly compared with the normal group but the levels of corticosterone in the blood of the GDT 400mg/kg group significantly decreased.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.4
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• pp.509-516
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• 2011

The performance of naked neck and normal chicken was evaluated with respect to growth, carcass, immune, biochemical and stress parameters under winter and summer seasons to assess the suitability of naked neck birds under high temperatures in the global scenario of climate change. The growth performance was significantly ($p{\leq}0.05$) higher in naked neck chicken in the summer season. The dressing percentage was significantly ($p{\leq}0.05$) higher in naked neck birds in both winter and summer season because of reduced plumage. The thigh, giblet and feather proportion significantly ($p{\leq}0.05$) varied between naked neck and normal chickens in summer season. The humeral immune response to sheep red blood cells (SRBC), Newcastle disease vaccine (NDV) and cutaneous basophil hypersensitivity (CBH) did not show any significant differences among the chicken groups. The protein and cholesterol concentration observed was within the normal ranges. The total cholesterol levels in plasma were significantly ($p{\leq}0.05$) lower in naked neck birds in both the seasons. H:L ratio was significantly ($p{\leq}0.05$) lower in summer season indicating less stress in naked neck chicken. Basophil and eosinophil concentration was significantly ($p{\leq}0.05$) higher in normal chicken in summer. The lipid peroxidation was higher in full feathered birds under summer stress. The enzyme glutathione reductase (GR) levels were significantly higher during the summer and varied significantly ($p{\leq}0.05$) between the normal and naked neck chicken in both seasons. The results indicated that the naked neck birds performed significantly better at high ambient temperatures with respect to growth, carcass and biochemical parameters. It was concluded that the ability of the naked neck chicken to adapt to high temperatures foresees a viable option for the biological mitigation of climate change.

• Journal of the Korean Home Economics Association
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• v.43 no.5 s.207
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• pp.199-219
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• 2005

The purpose of this study was to investigate the prevalence and to identify the related factors of overweight among young children. The study subjects were 138 children, aged 3-5, attending child care centers in the Kyungbuk area. We assessed a wide range of collected variables including general characteristics, anthropometric data, dietary habits, stress, food preferences, and food frequencies of young children, and anthropometric data and general characteristics of their parents. The results of this study were analyzed with $\chi$$^{2}$_ or t-test using SPSS package program. The subjects were classified into two groups using the weight for length index WLI criteria: normal group(n=101) and overweight group(n=37). Forty-nine percent of mothers of overweight children did not recognize their child's current overweight status. Scores for encountering criticized-violent situation stress, hurt-pride stress and total stress were higher in the overweight group than in the normal group. The frequency of snacking and the appetite of the overweight group were increased compared to those of the normal group. The overweight group had higher preferences for salad, kimbab, boiled rice with meat, vegetables and Chinese noodles, chicken, shell, banana, soybean milk, hotdog, and potato than the normal group. The overweight group showed higher consumption frequencies of pan-fried foods, egg, laver and strawbery compared to the normal group. Therefore, our results suggest that obese young children, as well as their parents, need more nutritional counseling education about dietary habits, food preference, recognition of normal weight and strategies for actively coping with stresstopreventandtreatobesityandtomaintainhealth. .

• Archives of Plastic Surgery
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• v.49 no.1
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• pp.115-120
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• 2022

Background In addition to vascular endothelial cells, vascular smooth muscle cells (VSMCs) are subject to continuous shear stress because of blood circulation. The angiogenic properties of VSMCs in extracranial arteriovenous malformations (AVMs) may exceed those of normal blood vessels if the body responds more sensitively to mechanical stimuli. This study was performed to investigate the hypothesis that rapid angiogenesis may be achieved by mechanical shear stress. Methods VSMCs were obtained from six patients who had AVMs and six normal controls. The target genes were set to angiopoietin-2 (AGP2), aquaporin-1 (AQP1), and transforming growth factor-beta receptor 1 (TGFBR1). Reverse-transcriptase polymerase chain reaction (RT-PCR) and real-time PCR were implemented to identify the expression levels for target genes. Immunofluorescence was also conducted. Results Under the shear stress condition, mean relative quantity values of AGP2, AQP1, and TGFBR1 in AVM tissues were 1.927±0.528, 1.291±0.031, and 2.284±1.461 when compared with neutral conditions. The expression levels of all three genes in AVMs were higher than those in normal tissue except for AQP1 under shear stress conditions. Immunofluorescence also revealed increased staining of shear stress-induced genes in the normal tissue and in AVM tissue. Conclusions Shear stress made the VSMCs of AVMs more sensitive. Although the pathogenesis of AVMs remains unclear, our study showed that biomechanical stimulation imposed by shear stress may aggravate angiogenesis in AVMs.

• Proceedings of the KSPS conference
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• 1996.10a
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• pp.207-207
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• 1996

The neutral tone is one of the most important distinguishing features in Beijing Mandarin, but there are two completely different views on its linguistic function: a special tone(Xu, 1980) versus weak stress(Chao, 1968). In this paper, the acoustic manifestation of the neutral tone will be explored to show that it is closely related to weak stress. 122 disyllabic words in which the second syllable carries the neutral tone, including 22 stress pairs, were uttered by a native male speaker of Beijing dialect and analysed by Kay Digital Sonagraph 5500-1. The results of the acoustic analysis are presented as follows: 1) The first two formants of the medial and the syllabic vowel moves towards that of central vowel with a greater magnitude in the syllable with the neutral tone than in the syllable with any of the four normal tones. Also the vowel ending, and nasal coda /n/ and / / in the syllable with the neutral tone tends to be deleted. 2) In the syllables with the neutral tone, there are strong carryover coarticulations between the medial and syllabic vowel and the preceding unvoiced consonant. In general, the vowel is affected to move towards the position of the central vowel with more greater magnitude by coronal consonant than by labial or velar consonant. 3) In the syllable with the neutral tone, when and only when it precedes a syllable with tone-4, the high vowel following [f], [ts'], [s], [ts'], [s], [tc'] or [c] tends to be voiceless. 4) It can be seen from the acoustical results of 22 stress pairs that the duration of the syllable with the neutral tone is on the average reduced to 55% of that of the syllable with the four normal tones, and the duration of the final in the syllable with neutral tone is on the average reduced to 45% of that of the final in the syllable with the four normal tones(Lin & Yan 1980). 5) The FO contour of the neutral tone is highly dependent on the preceding normal tone(Lin & Yan 1993). For a number of languages it has been found that the vowel space is reduced as the level of stress placed upon the vowel is reduced(Nord 1986). Therefore we reach the conclusion that the syllable with neutral tone is related to weak stress(Lin & Yan 1990). The neutral tone is not a special tone because the preceding normal tone.

• Geomechanics and Engineering
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• v.14 no.4
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• pp.337-344
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• 2018

The study of the mining effect influenced by a normal fault has great significance concerning the prediction and prevention of fault rock burst. According to the occurrence condition of a normal fault, the stress evolution of the working face and fault plane, the movement characteristics of overlying strata, and the law of fault slipping when the working face advances from footwall to hanging wall are studied utilizing UDEC numerical simulation. Then the inducing-mechanism of fault rock burst is revealed. Results show that in pre-mining, the in situ stress distribution of two fault walls in the fault-affected zone is notably different. When the working face mines in the footwall, the abutment stress distributes in a "double peak" pattern. The ratio of shear stress to normal stress and the fault slipping have the obvious spatial and temporal characteristics because they vary gradually from the higher layer to the lower one orderly. The variation of roof subsidence is in S-shape which includes slow deformation, violent slipping, deformation induced by the hanging wall strata rotation, and movement stability. The simulation results are verified via several engineering cases of fault rock burst. Moreover, it can provide a reference for prevention and control of rock burst in a fault-affected zone under similar conditions.

• Korean Journal of Human Ecology
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• v.4 no.1
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• pp.1-12
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• 1995

The purpose of this research is to provide fundamental data, which is essential to develop counselling and educational program for autistic family, analyzing family stress and coping strategies of severely autistic child family, mildly autistic child family and normal child family. The result of this research is as follows: There are significant differences among severely autistic child family, mildly autistic child family and normal child family applying to three types of family stress. Also there are significant differences among severely autistic child family, mildly autistic child family and normal child family applying to religions supporting methods and relatives and friend's supporting methods. This research is not discussed that autistic child family with not education. Therefore the follow-up studies need to know that difference between with education and not with education.

• Korea-Australia Rheology Journal
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• v.11 no.3
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• pp.225-232
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• 1999

This study presents 1-dimensional simple model for sheet casting or rectangular fiber spinning process. In order to achieve this goal, we introduce the concept of force flux balance at the die exit, which assigns for the extensional flow outside the die the initial condition containing the information of shear flow history inside the die. With the Leonov constitutive equation that predicts non-vanishing second normal stress difference in shear flow, we are able to describe the anisotropic swelling behavior of the extrudate at least qualitatively. In other words, the negative value of the second normal stress difference causes thickness swelling much higher than width of extrudate. This result implies the importance of choosing the rheological model in the analysis of polymer processing operations, since the constitutive equation with the vanishing second normal stress difference is shown to exhibit the characteristic of isotropic swelling, that is, the thickness swell ratio always equal to the ratio in width direction.