• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.376-381
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• 1992

In order to study the effect of modified atmosphere storage on extending shelf life of mushrooms, oyster mushroom and Shiitake were wrapped with polyethylene film (PE, $50\;{\mu}m$), and stored at $0.5^{\circ}C$. Mushrooms packed with conventional hardboard box (4kg) lost marketability within $5{\sim}6$ days due to weight loss, shrinkage, browning, spore formation and/or mycellium growth. PE-packing could prevent or retard the deterioration of the mushrooms in the aspects of appearance, texture, discoloration, and microbial contamination. This situation can be best characterized by the reduced respiration rate resulted from the elevated level of carbon dioxide and the reduced level of oxygen in the bag. Although the appearance of the oyster mushroom was maintained for one month, its shelf life was limited to 15 days because of tissue softening. Discoloration of the pileus of shiitake mushroom appears to be the most important factor to determine its marketability. For example, extension of shelf life of Dongo was limited to 15 days, principally due to the browning of the pileus. Shelf life of Hawgo whose color of the pileus changed little over the experimental period, however, could be extened to more than one month.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.108-114
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• 2017

The effect of 1-methylcyclopropene (1-MCP) at $1.0{\mu}L{\cdot}L^{-1}$ was compared with control and $10{\mu}L{\cdot}L^{-1}$ ethylene treatment to evaluate softening control of apple (Malus ${\times}$ domestica Borkh.) fruit for 180 days at $0.5^{\circ}C$ in the air, followed for 28 days at a room temperature. 1-MCP or 1-MCP+ethylene treatment maintained high fruit titratable acidity and firmness after 120 days during the cold storage, which was similarly observed for 28 days at a room temperature. 1-MCP treatment maintained fruit firmness more than 14 N during the cold storage and shelf-life at room temperature. Fruit surface red color was not consistently affected by the treatments during the cold storage but enhanced more than 4.0 by 1-MCP at 21- and 28-days of room temperature. Control or ethylene treatment advanced overall preceeding of fruit softening as rapid ethylene production and respiration rates at 90 days during the cold storage increased to a climacteric maximum. Therefore, pre 1-MCP-treated fruit maintained high fresh condition at a long-term low storage + approximately one month room temperature-storage under $10{\mu}L{\cdot}L^{-1}$ ethylene treatment.

• Journal of fish pathology
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• v.13 no.1
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• pp.21-29
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• 2000

A new nutritional disease has occurred among the hatchery-reared Korean bullhead fingerlings (Pseudobagrus fulvidraco) in the Chonbuk Province in September 1997. Diseased fish were all dead within 3-7 days, showing sluggish behavior, head up and tail down swimming. Most characteristic clinical signs were anaemia, clubbed and fused gill, skin desquamation. haemorrhage around the mouth and at the base of pectoral fins. Any causative bacteria and parasites were not isolated from the lesions and internal organs of the diseased fish. The hepatosomatic index, red blood cell count, hematocrit, hemoglobin and erythrocytes size of peripheral blood in the diseased fish were remarkably decreased compared with those of normal fish. In the histopathological observations, epithelial hyperplasia of the gill filaments initiated at the base of the gill was pronounced. This symptom was the characteristic appearence of all the diseased fish. A 0.6% saline bath and feeding a pantothenic acid-supplemented diet were conducted to decrease the mortality. Ten days after 0.6% saline bath or 25 days after feeding a pantothenic acid supplemented diet resulted in decreasing in the mortality. Microscopic appereance of the gill from the recovered fish was similar to that of the gill from healthy fish. These results indicate that the disease was caused by deficency of pantothenic acid in their diet and that 0.6% saline bath or supplementation of pantothenic acid in the diet was an effective way to decrease the mortality.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1987.05a
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• pp.15.2-16
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• 1987

사성이란 후두의 발생기능에 장애가 있을 때 생기는 후두질환의 가장 대표적인 주증상으로 인간 문화의 발달에 병행되어서 대화에 의한 전달수단이 중요시되고 또한 암에 대한 인식이 높아져 사성을 호소하는 환자들이 많아지는 경향이 있다. 이에 저자는 1980년 1월부터 1984년 12월까지 이화여자대학교 의과대학 부속병원 이비인후과 외래에 내원한 신외래환자 총 24,949명 중 사성을 주소로 한 800명의 환자에 대하여 병력지를 기준하여 각 질환을 통계적으로 분석 검토하여 다음과 같은 성적을 얻었다. 1) 이비인후과 외래환자 총 24,949명중 사성환자는 800명으로 약 3.2%이었다. 2) 외래사성환자 800명중 남자 336명, 여자 464명으로 남녀비는 약 1 : 1.4이었다. 3) 질환별로는 급성 후두염 248예(31.0%), 만성 후두염 186예(23.3%), 성대결절 160예(20.0%), 성대폴립 90예(11.3%), 성대마비 56예(7.0%), 후두 유두종 12예(1.5%), 후두암 9예(1.1%)이었다. 4) 연령별로는 30대가 213예(26.6%), 20대가 190예(23.8%), 40대가 179예(22.4%)의 순이었다. 5) 각 질환별 최다연령은 급성 후두염 30대 73예(29.4%), 만성 후두염 30대 53예(28.5%), 성대결절 30대 52예(32.5%), 성대폴립 40대 26예(28.9%), 성대마비 40대 14예(25.0%), 후두암 50대 6예(66.7%)이었다. 6) 발병부터 초진까지의 기간은 10일 이내가 153예(19.1%)로 제일 많았고 1개월∼3개월 138예(17.3%), 11일∼l개월 119예(14.9%)의 순이었다. 7) 각 질환에 따른 발병부터 초진까지의 기간의 최다분포는 급성 후두염은 10일 이내가 117예(47.2%), 만성 후두염은 3개월∼6개월이 44예(23.7%), 성대결절은 3개월∼6개월이 40예(25.0%), 성대폴립은 6개월∼1년이 20예(22.2%), 성대마비는 10일이내가 12예(21.4%)이었다. 8) 질환별 동반증상 분포는 사성만을 호소한 경우가 394예(41.4%)로 가장 많았고 동반증상으로는 인두통, 이물감, 객담, 기침, 연하장애, 호흡곤란의 순이었다. 9) 저자의 연도별 사성환자의 평균발생빈도(3.2%)를 문(1981)의 1975년 1월부터 1979년 12월(만 5년간)까지의 평균발생빈도(2.9%)와 비교할 때 증가하였다.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.187-192
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• 2021

This study was conducted to compare the quality of baby leaves grown under several temperature conditions and the storage properties of MA storage for romaine lettuce. It was grown for 5 weeks under an artificial light source (200 µmol·m^-2·s^-1) in a chamber at 21℃, 28℃, and 35℃. The growth and quality of red romaine lettuce that grown in different temperatures were investigated at the end of cultivation, and the oxygen, carbon dioxide, and ethylene concentrations in the 20,000 cc OTR film and perforated film packed with lettuces were measured for 36 and 12 days, respectively. The red romaine lettuce baby leaf was examined for color, chlorophyll, and visual quality at the end of storage. The maximum quantum yield of baby leaf grown in different temperatures at 7days before the harvest was higher at 21℃ and 28℃ growth temperature treatments. On harvest day, the leaf length measured was longest at 28℃, and the leaf width was wider at 21℃ and 28℃, and the number of leaves was similar to 5-6 at all cultivation temperatures. Leaf weight, root weight, and dry weight were found to be higher at 21℃, and tended to decrease as the cultivation temperature increased. The concentration of ethylene in the film of the MA storage treatments was maintained at 1~2 µL·L^-1 until the end of storage in all treatments regardless of the cultivation temperature. Oxygen concentration in the MA treatment used 20,000 OTR film was maintained at around 19.5%, and carbon dioxide concentration around 1% that was satisfied the CA conditions. Both Hunter a^* and b^* values were generally higher in the MA storage treatment at the end of storage day. The chlorophyll content was decreased as the cultivation temperature increased, and was lower in the MA storage treatment than in the perforated film treatment. Visual quality was 3 points or higher in the MA storage treatment at 21℃ growth treatment, and it was maintained marketability. As the above results, the growth of baby leaves of romaine lettuce was the best at 21℃ treatment, and the lower the cultivation temperature, the longer the shelf life. And it was possible to extend the shelf life by 3 times by showing excellent visual quality at the MA storage treatment that satisfies the carbon dioxide concentration of CA condition until the end of storage day.

• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.966-971
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• 2003

Purpose : It is now well established that infection and inflammation play an important role in the pathogenesis of ischemic brain damage. The loss of neutrophils from systemic circulation is an associated finding in injury mediated by granulocyte. Periventricular leukomalacia(PVL) caused by ischemia is the principal form of brain injury in premature infants. This study was conducted to evaluate whether the low neutrophil count is associated with periventricular leukomalacia(PVL) in premature infants. Methods : Retrospective review of medical records was undertaken. Subjects were premature infants with a birth weight of less than 1,500 gm, admitted to the Neonatal Intensive Care Unit of Kyungpook University Hospital. A complete blood count of peripheral blood was done within the 1st hour of life. Neutropenia was defined as absolute neutrophil count < $1,500/mm^3$, PVL as increased periventricular echodensities followed by cyst formation on ultrasonography or corresponding signs on brain MRI. Results : Thirteen infants out of a total population of 37 revealed neutropenia. Respiratory distress syndrome and requirement for respiratory support were not different between infants with neutropenia( neutropenia group) and infants without neutropenia(control group). Intraventricular hemorrhage (IVH) and grade 3 and 4 IVH were more frequent in neutropenia group(P<0.05). There was no statistically significant increase of PVL in neutropenia group. The neutrophil count was $18,760.0{\pm}10,266.1/mm^3$, $7,272.0{\pm}7,435.0/mm^3$ infants with PVL and $11,131.7{\pm}3,386.5/mm^3$, $2,407.5{\pm}1,933.1/mm^3$ in infants without PVL, respectively. The frequency of mechanical ventilation and artificial surfactant therapy was higher in infants with PVL compared with infants without PVL, but statistical analysis was not performed due to small number of subjects. Conclusion : A low number of neutrophils in the systemic circulation was not associated with an increased risk of PVL in premature infants.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.05a
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• pp.35-81
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• 1998

Distinct Element Method(DEM) has a great advantage to model the discontinuous behaviour of jointed rock masses such as rotation, sliding, and separation of rock blocks. Geometrical data of joints by a field monitoring is not enough to model the jointed rock mass though the results of DE analysis for the jointed rock mass is most sensitive to the distributional properties of joints. Also, it is important to use a properly joint law in evaluating the stability of a jointed rock mass because the joint is considered as the contact between blocks in DEM. In this study, a stochastic modelling technique is developed and the dilatant rock joint is numerically modelled in order to consider th geometrical and mechanical properties of joints in DE analysis. The stochastic modelling technique provides a assemblage of rock blocks by reproducing the joint distribution from insufficient joint data. Numerical Modelling of joint dilatancy in a edge-edge contact of DEM enable to consider not only mechanical properties but also various boundary conditions of joint. Preprocess Procedure for a stochastic DE model is composed of a statistical process of raw data of joints, a joint generation, and a block boundary generation. This stochastic DE model is used to analyze the effect of deviations of geometrical joint parameters on .the behaviour of jointed rock masses. This modelling method may be one tool for the consistency of DE analysis because it keeps the objectivity of the numerical model. In the joint constitutive law with a dilatancy, the normal and shear behaviour of a joint are fully coupled due to dilatation. It is easy to quantify the input Parameters used in the joint law from laboratory tests. The boundary effect on the behaviour of a joint is verified from shear tests under CNL and CNS using the numerical model of a single joint. The numerical model developed is applied to jointed rock masses to evaluate the effect of joint dilation on tunnel stability.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.239-247
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• 2008

The objective of this investigation was to examine oxygen consumption (OC) and operculum movement number (OMN) of rainbow trout Oncorhynchus mykiss as a function of changes in water temperature (WT). The WT of the rearing facility was increased from $4^{\circ}C$ to $28^{\circ}C$ stepwise at $1^{\circ}C$ day at each WT (5, 10, 15, 17, 20, 23, 26, and $28^{\circ}C$) then OC and OMN were measured. The OC of the fish increased linearly with WT: O=25.0240 WT+17.5400 in the range of $4{\sim}23^{\circ}C$ However, at 26 and $28^{\circ}C$ the OC declined to around the level at $10^{\circ}C$. The OMN also increased linearly with temperature: OMN=4.4847 WT+59.2150 in the range of $4{\sim}23^{\circ}C$ but at 26 and $28^{\circ}C$ the OMN of the fish dropped slightly. The OC and OMN of the fish showed peak at $23^{\circ}C$ with the lowest values at $4^{\circ}C$. In the range of $4{\sim}23^{\circ}C$, the relationship between OC and OMN of the fish was expressed as a linear equation: OC=0.0923 OMN-308.2100. The OC of fish transferred from $15^{\circ}C$ to certain temperatures without acclimation showed a lower OC at 5 and $10^{\circ}C$ but above $15^{\circ}C$ the OC increased/decreased with temperature. The trout died in temperatures above $28^{\circ}C$ even when acclimated step by step with a $1^{\circ}C$ day increase in WT. In this experiment, a negative physiological changs occurred in the experimental fish at $23^{\circ}C$ suggesting that the optimal physiological temperature range of rainbow trout is $10{\sim}20^{\circ}C$.

• Journal of Animal Environmental Science
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• v.18 no.sup
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• pp.21-28
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• 2012

Since the temperature during summer is higher than the temperature which is suitable for milking cows, high temperature stress have severely affected dairy farmers due to decreased milk production. This study was carried out to investigate the effect of rainwater sprinkling system for reducing heat stress in milking cows during intense heat time. Treatment conditions were divided into 2 types ; No rainwater sprinkling (T1) and Rainwater sprinkling (T2). Temperature in the milking cow shed, feed intake, milk yield, respiration rate and rectal temperature were measured to investigate the effect of hot environment on the physiological, productive responses in milkig cows. The results obtained are summarized as follows : The daily milk yields were 24.5 and 27.4 kg per head in T1 and T2 during experimental period. The respiration rate was significantly higher in T1 than those of T2. The rectal temperature in T1 ($40.6^{\circ}C$) was higher than those of T2 ($39.8^{\circ}C$). It was suggested that rainwater sprinkling system installed in the dairy cow shed was effective means to reduce heat stress of milking cow.