• Applied Microscopy
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• v.47 no.4
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• pp.238-241
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• 2017

A study on the visual cell and eyeball of the endemic Korean species Liobagrus mediadiposalis was investigated by light and electron microscopes. The retina of a small and 2 mm-diameter round eye was thin, $151.0{\pm}4.0{\mu}m$ and has two visual cells, a single cone and a rod cell. The single cone cells are short and thick, $18.0{\pm}0.9{\mu}m$ in length and $5.1{\pm}0.7{\mu}m$ (n=30) in diameter, while the rod cells are longer and thinner, $54.8{\pm}2.9{\mu}m$ in length and $3.3{\pm}0.6{\mu}m$ in diameter. The cone cells are seen an irregular and random mosaic pattern, and the rod cells are also randomly situated at between cone cells. As a rare phenomenon, such structure is one of characteristics reflecting the eye of a nocturnal and bottom-dwelling freshwater fish. The ultrastructure of visual cells was observed with scanning and transmission electron microscopy, both cone and rod cells are divided into an inner segment with numerous mitochondria and an outer segment with stacks of membrane discs.

• Childhood Kidney Diseases
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• v.25 no.1
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• pp.40-43
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• 2021

Enuresis is intermittent urinary incontinence during sleep at night in children aged 5 years or older. The main pathophysiology of enuresis involves nocturnal polyuria, abnormal sleep arousal, and low functional bladder capacity. In rare cases, enuresis is an early symptom of endocrine disorders such as diabetes or thyroid disorders. Herein, we report a case of a 12-year-old girl with enuresis as a rare initial presentation of Graves' disease. She complained of nocturnal enuresis from a month before visiting our clinic. She also complained of urinary frequency, headache, and weight loss. On physical examination, she had tachycardia, intention tremors, and a diffuse goiter on her anterior neck with bruit on auscultation. Her thyroid function test results revealed hyperthyroidism, and Graves' disease was diagnosed as the thyroid stimulating hormone receptor autoantibody was positive. After treatment for Graves' disease with methimazole, symptoms of enuresis resolved within 2 weeks as she became clinically and biochemically euthyroid. In children with secondary enuresis, Graves' disease should be considered as a differential diagnosis, and signs of hyperthyroidism should be checked for carefully.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.636-644
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• 2019

The purpose of this study was to investigate the callings of nocturnal birds using bioacoustic recording technology to identify species and to analyze the ecological characteristics of each species. Three sites - Seoraksan National Park, National Institute of Ecology, and Mudeungsan National Park - were investigated. The investigation period was from the middle of April 2018 to early March 2019 for Seoraksan national park, from late February of 2018 to the middle of February 2019 for the National Institute of Ecology, and from the middle of February 2018 to the end of August 2018 for Mudeungsan National Park. The main research results are as follows. Firstly, nocturnal bird species identified by the survey included Caprimulgus indicus, Otus sunia, Zoothera aurea, Bubo bubo, and Strix uralensis, 5 species in total. Secondly, the breeding call period of each species was from early May to early August for C. indicus, from early April to the end of September for O. sunia, from early March to early October for Z. aurea, from late September to early February for B. bubo, and from mid-January to early March for S. uralensis. Thirdly, the mating call rhythm was between 16:00 and 10:00 on the following day for all the observed species in the three regions, and the peak time zone was from 20:00 to 06:00 on the following day. Fourthly, there was no correlation between the cumulative call frequency and the precipitation for each species. Fifthly, the mean temperature during the period when the specific calls of nocturnal birds were detected was -4.00 ℃ for S. uralensis, 2.58 ℃ for B. bubo, 13.66 ℃ for Z. aurea, 19.50 ℃ for O. sunia, and 20.77 ℃ for C. indicus. The ANOVA results showed that there was a significant difference in mean temperature for the calling by species and that the mean temperature was S. uralensis, B. bubo, Z. aurea, and O. sunia-C. indicus, in the ascending order, for 4 groups in total. The period of the specific mating calls confirmed by the study is a period in which the frequency of calls was the highest among the periods when the specific calls were detected. Since it is associated with the known mating period of each species, the period of the high frequency of calls confirmed by the bioacoustic monitoring can be regarded as the mating season. This study is meaningful in that it is the early research that has used the bioacoustic recording technology to identify species and ecological characteristics of species of nocturnal birds in Korea.

• Journal of the Korean Geographical Society
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• v.30 no.3
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• pp.230-241
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• 1995

The Characteristics of nocturnal temperature fields were analyzed to understand the factors of freezing-and-cold damages on orange orchards in Cheju Island. Temperatures were measured from January 7th through 27, 1995 at 25 sites in an area of 1x1.25$ extrm{km}^2$, Wasan-ri, Chochon-up, Pukcheju-kun located on the northeastern slope of Mt.Hanla. Several other weather elements such as wind and cloud were observed as supplementary data. Surface weather maps were also analyzed to clarify the influence of prevailing pressure patterns on the temperature fields. The vertical temperature profiles were obtained at the height from the ground up to 360 cm in 30 cm intervals at site 3, a frost hollow, and site 10 on the upper slope. The results show that freezing damages occured in the hollows, terrain depressions, rather than at the upper slope due to nocturnal radiation cooling as well as accumulation of cold airflow from Mt.Hanla. Windbreaks of densely planted Japanese ceders with stone-walls also roled as obstacles to the cold airflow in nights with Clear skies and light winds. The maximum intensity of temperature inversion in hollows, quasi-cold air lake, was 3.1$^{\circ}C$. Cold air from Mt.Hanla was trapped in the depressions up to a height of 90cm forming frost pocket. Man-made facilities such as shelterbelt or stone-wall which are built to prevent the penetration of cold north-westeries in winter aggravated the cold damage. The differance of daily minimum temperatures between before and behind shelterbelts was 2.$0^{\circ}C$. The man-made convection by smudgin which raised the temperatures up to 3.8$^{\circ}C$ can reduce the cold damage in the hellows.

• Clinics in Shoulder and Elbow
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• v.18 no.3
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• pp.133-137
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• 2015

Background: The aim of this study was to investigate the demographic and clinical characteristics of patients with primary frozen shoulder in a Korean population. Methods: A total of 1,373 patients whose shoulders were diagnosed with primary frozen shoulder across 11 resident-training hospitals were reviewed retrospectively. Various demographic characteristics and clinical characteristics according to gender and presence of diabetes were evaluated. Results: The average age of patients was 55.4 years. Gender proportion was 58.3% females and 41.7% males. The frozen shoulder involved the non-dominant arm in 60.7% of patients and the bilateral arms in 17.6% of patients. The average duration of symptoms was 8.9 months, and 51.3% of patients had experienced nocturnal pain. Comorbidities associated with frozen shoulder in our sample of patients included diabetes (18.7%), cardiovascular diseases (17.7%), thyroid diseases (5.4%), and cerebrovascular diseases (3.6%). The diabetic group was correlated with the following demographic and clinical characteristics: old age, involvement of the dominant arm, nocturnal pain, long duration of symptoms, and no history of trauma. Further, we found that, in males, having a frozen shoulder was significantly correlated with a history of trauma; in females, having a frozen shoulder was significantly correlated with having thyroid diseases. Conclusions: These demographic data of primary frozen shoulder in the Korean population were consistent with those of previously reported epidemiologic studies. Primary frozen shoulder with diabetes was correlated with old age, bilateral involvement, long duration of symptoms, and nocturnal pain.

• Sleep Medicine and Psychophysiology
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• v.4 no.2
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• pp.201-212
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• 1997

Objectives: We attempted to study sleep habits and insomnia-associated factors in Korean rural adult population. Methods : In 1,441 adult subjects of three rural communities selected by cluster sampling, we administered an epidemiologic survey using questionnaire methods from July 14, 1996 to July 28, 1996. Results : 1) Mean sleep latency and mean time to sleep again after awakening during nocturnal sleep were longer in females than in males. Females suffered more frequently from insomnia symptom, awakening during nocturnal sleep. morning headache, dysphoric mood in the morning, and the feeling of 'not refreshed' on waking-up than males. 2) The older age group (defined as those older than 65 years) was found to have earlier bed-time, longer sleep latency, more frequent nocturia, longer time to sleep again after awakening during nocturnal sleep, and more frequent insomnia symptom. 3) The presence of insomnia symptom more than once a week was significantly associated with suffering from physical illness, being divorced-separated-widowed, frequently feeling depressed, nocturia, or low education level. 4) In multiple logistic regression analysis, old age, being female, low education level, frequently feeling depressed, and nocturia were independently associated with the presence of insomnia symptom more than once a week. Conclusion : We conclude that, in a Korean rural adult population, insomnia symptom increases with age and females usually suffer more from insomnia symptom than males. In addition, low education level, feeling depressed mood frequently, and nocturia are found to be significantly associated independently with the presence of insomnia symptom more than once a week.

• Sleep Medicine and Psychophysiology
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• v.10 no.1
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• pp.12-19
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• 2003

Sleepiness, or hypersomnia, is a relatively common complaint and one of the main problems of modern society. Accurate evaluation and diagnosis of sleepiness are important. The methods used for evaluating sleepiness are subjective measures or self-evaluations, performance decrease measures, sleep propensity measures, and arousal decrease measures. A clear and detailed history is important in differential diagnosis of sleepiness because symptoms of sleepiness may be expressed in terms of 'tiredness' or 'fatigue' that do not directly denote sleepiness. Comprehensive diagnostic evaluation is also invaluable because these symptoms may result from a variety of causes ranging from medical disorders to insufficient nocturnal sleep.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2001.06a
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• pp.68-71
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• 2001

밝고 바람이 없는 저녁, 지표근처의 냉각은 많고 일출 전후에 최저기온이 나타난다(Nishiyama, 1985). 그리고 기온은 지표근처에서 가장 낮고 고도가 높아질수록 높아진다. 이러한 상태를 지표역전(surface inversion) 또는 지면역전(ground inversion)이라 한다. 지표 역전층은 지표근처에 강한 복사냉각(radiative cooling)에 의해 형성되고, 다른 하나는 차가운 공기의 drainage에 의해 이류(advection) 되어 지표근처에 축적된다.(중략)

• Animal Systematics, Evolution and Diversity
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• v.25 no.1
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• pp.65-80
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• 2009

Pyrgotidae is a small acalyptrate family including about 370 species worldwide and little attention has been given to their systematics until recently. Latest changes in taxonomic status of some of the Korean species made this review inevitable. In the present study, the Korean pyrgotid species are reviewed with discussion of their taxonomic status. We also provide a revised key to all 14 Korean species (seven Adapsilia, three Eupyrgota, two Parageloemyia, one Porpomastix, and one Tephritopyrgota species) supplemented by digital images to facilitate accurate identification.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2018.06a
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• pp.136-136
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• 2018