• Journal of Chest Surgery
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• v.18 no.1
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• pp.1-6
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• 1985

Isolated sinus node cells of the rabbit were used to assess the effects of extracellular Na, K, Ca and Mg concentrations on cardiac pacemaker activity. With intracellular glass micro-electrodes spontaneous action potentials of SA node were recorded and the effects of various ions and their blockers were analyzed in terms of the cycle length, the amplitude and the duration of action potentials, the results obtained were as follows. 1. Sodium reduction [up to 30%] decreased the amplitude of action potential and lengthened the cycle length. TTX, specific blocker of Na channel slightly lengthened the cycle length. 2. Increasing potassium ion concentration, the duration of action potential decreased and the frequency increased in 6mM, however, spontaneous action potential was stopped in 24 mM. Barium ion known to be decreasing K conductance increased the duration of action potential but no significant change in the cycle length was noticed. 3. Calcium ion has shortening effect on the duration and the cycle length of action potential but not with dose-dependent manner. Cadmium ion .[0.02mM] lengthened cycle length and the duration of action potential. 4. Increasing the concentration of magnesium ion the cycle length was lengthened, significantly.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.5 no.2
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• pp.181-195
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• 1998

This study is to evaluate the decubitus ulcer healing effect of occlusive dressing with hydrocolloid and traditional dry dressing for home care nursing clients. Study design was quasi-experimental pre-post test design. Control group(15 person) was treated decubitus wound with traditional dry gauze dressing, and experimental group(17 persons) was treated decubitus ulcer with occlusive dressing with hydrocolloid and calcium alginate(17 persons). Study period was from 8/1/97 to 12/31/97. Subject subjects was 17 males and 15 females with 2nd phase over decubitus ulcer aged 30 to 70 who have been registered as home care nursing clients in Nurse's Association in Seoul city. Outcome variables were stages, size of decubitus ulcer, pain at dressing time and exudate amount. Study result as follows. Occlusive dressing with hydrocolloid was superior to traditional gauze dressing decreasing ulcer size and phase, and shortening treatment period. Dressing change of occlusive dressing was easier than that of traditional gauze dressing. In conclusion, occlusive dressing was recommended to treat decubitus ulcer in home care patients even if hydrocolloid is expensive to gauze dressing because of treatment effect and easeness of dressing.

• Speech Sciences
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• v.7 no.1
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• pp.187-201
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• 2000

This study was done to investigate the English vowels in relation to the foreign accent. In this study, I also tried to find out the foreign accent of the English diphthong /o/ and front low vowel /${\ae}$/ when Koreans speak English. The reason why I chose these vowels is that these vowels, /o/ and /${\ae}$/, are difficult for Koreans to discern and pronounce. Koreans show a foreign accent in their pronunciation. In order to find out the reason for a Korean foreign accent, experiments were carried out with the help of acoustic instruments. According to the results of the experiment, Koreans showed a foreign accent in their English pronunciation of vowels in relation to their utterance positions. Americans showed a final lengthening effect but Koreans showed a final shortening effect. This means that Koreans showed a foreign accent in the final stressed syllable of a sentence. In addition to this, the duration of two English vowels, /o/ and /${\ae}$/, showed considerably different features between Koreans and Americans. In fact, in the pronunciation of the diphthong /o/, the tongue moves from one position to another. The two articulations of a diphthong can be described as the nucleus plus a glide. However, most Koreans have no idea of this phenomenon and pronounce the diphthongs like two separate monophthongs. This causes a great difference in the lengths of English diphthong /o/ between Koreans and Americans.

• Biomedical Science Letters
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• v.19 no.3
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• pp.188-194
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• 2013

Ulcerative colitis (UC) is an inflammatory bowel disease, which is a chronic gastrointestinal disorder. Adenophorae Radix (AR) has been used as a traditional medicine for various diseases including strengthening cardiac function, allaying a fever, and easing pain and cough. However, the regulatory effects of AR in intestinal inflammation are not yet understood. This study attempted to determine the effect of AR in dextran sulfate sodium (DSS) - induced colitis in mice. The colitis mice were induced by drinking water containing 5% DSS for 7 days. The results showed that mice treated with DSS showed remarkable clinical signs, including weight loss, and reduced colon length. Administration of AR attenuated weight loss, colon shortening and inhibited the levels of interleukin (IL) - 6 in DSS - treated colon tissues. These results provide experimental evidence that AR might be a useful therapeutic medicine for patients with UC.

• Korean Journal of Animal Reproduction
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• v.25 no.3
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• pp.231-235
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• 2001

Gestation duration of cow is an important economical trait. Shortening the gestation duration decreases the production cost and increases the competitiveness of Hanwoo industry. Thus, this study was carried out to analyse the effect of expected factors on gestation duration and make an alternative idea for reduced gestation duration. Gestation duration was not affected by cow-parity, but significantly affected by farm, Al year and sire. Therefore, reducing the gestation duration of Hanwoo may require both providing optimum feeding environment and nutrition management for cow and selecting optimum sire for AI.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.262-266
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• 2009

To evaluate the anticolitic effect of red ginseng (RG, the steamed root of Panax ginseng CA. Meyer, Araliaceae), RG and its representative constituents, ginsenosides Rg3 and Rh2, were orally administered to dextran sulfate sodium (DSS)-induced colitic mice and inflammatory markers investigated. RG and its constituents, ginsenosides Rg3 and Rh2, inhibited colon shortening and myeloperoxidase activity induced by DSS. The ginsenosides Rg3 and Rh2 inhibited mRNA expression of interleukin (IL)-$1{\beta}$ as well as protein levels of IL-$1{\beta}$ and IL-6. These ginsenosides also inhibited the activation of a transcription nuclear factor (NF)-${\kappa}B$. Ginsenoside Rh2 was a more potent inhibitor than ginsenoside Rg3. The anticolitic effects of these ginsenosides were comparable with sulfasalazine.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.54-59
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• 2008

The poor maintenance and management of HVAC systems finally lead to the shortening of the life expectancy and result in the increase of operating costs and energy consumptions due to low efficiencies. Also, it is essential to try to develop ways to adequately maintain and to use the building facilities efficiently in order to preserve earth environment and the limited resource. In this study, an analysis on the maintenance and management cost for HVAC systems was carried out with the capacity of equipment. Besides, the LCC(Life Cycle Cost) based analysis was carried out to verify the effect of the doing maintenance and management. As the results, the case of the good maintenance and management is able to save LCC to 11 % than the case of the poor method.

• Phonetics and Speech Sciences
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• v.6 no.2
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• pp.141-151
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• 2014

This study reports anti-hierarchical initial-syllable lengthening of an utterance-internal phrase in Korean. That is, the phrase-initial syllable (e.g., /a/ of "apa-do" or /ma/ of "mapa-do") starting with a voiced phoneme (i.e., vowels or voiced consonants) manifests itself as significantly longer when it is preceded by another phrase without a pause than when it leads an utterance or follows a pause utterance-internally. The phenomenon was examined with regard to two other factors: (1) tempo and (2) tenseness of the consonant (/p, $p^{\prime}$, $p^h$/) following the target syllable /a/. First, the effect of tempo on initial lengthening was not significant. Apart from the statistical significance, however, a tendency was observed, i.e., the slower the tempo is, the greater the lengthening. By contrast, the faster the tempo is, the higher the ratio (%) of lengthening. Second, contrary to our expectations, initial-syllable lengthening was even greater before tense stops /$p^{\prime}$, $p^h$/ than before lax stop /p/ regardless of tempo, and it was remarkable when it comes to the ratio (%), which means that initial lengthening is free of the pre-consonantal vowel shortening effect. Final-syllable lengthening is a pre-boundary marker, while the initial-syllable lengthening is regarded as a post-boundary marker of a phrase.

• Journal of Biosystems Engineering
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• v.38 no.1
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• pp.41-47
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• 2013

Purpose: The objectives of this study were to construct the solar drying system with evacuated tubular solar collector and to investigate its performance in comparison with indoor and outdoor dryings. Methods: Solar drying system was constructed with using CPC (compound parabolic concentrator) evacuated tubular solar collector. Solar drying system is mainly composed of evacuated tubular solar collector with CPC reflector, storage tank, water-to-air heat exchanger, auxiliary heater, and drying chamber. Performance test of solar drying system was conducted with drying of agricultural products such as sliced radish, potato, carrot, and oyster mushroom. Drying characteristics of agricultural products in solar drying system were compared with those of indoor and outdoor ones. Results: Solar drying system showed considerable effect on reducing the half drying time for all drying samples. However, outdoor drying was more effective than indoor drying on shortening the half drying time for all of drying samples. Solar drying system and outdoor drying for oyster mushroom showed the same half drying time. Conclusions: Oyster mushroom could be dried easily under outdoor drying until MR (Moisture Ratio) was reached to about 0.2. However, solar drying system showed great effect on drying for most samples compared with indoor and outdoor dryings, when MR was less than 0.5.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.11
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• pp.904-913
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• 2002

In this study, a dynamic analysis of the reciprocating compression mechanism considering viscous friction force of a piston used in small refrigeration compressors is performed. The length of cylinder in this class of compressors is shortening to diminish the frictional losses of the piston-cylinder system. So, the contacting length between piston and cylinder liner is in variable with the rotating crank angle around the BDC of the reciprocating piston. In the problem formulation of the compression mechanism dynamics, the change in bearing length of the piston and all corresponding viscous forces and moments are considered in order to determine the trajectories of piston and crankshaft. The piston orbits for viscous friction model and Coulomb friction model were used to compare the effect of the friction forces of piston on the dynamic trajectories of piston. To investigate the effect of friction force acting on the piston for the dynamic characteristics of crankshaft, comparison of the crankshaft loci is given in both viscous model and Coulomb model. Results show that the viscous friction force of piston must be considered in calculating for the accurate dynamic characteristics of the reciprocating compression mechanism.