• Korean Journal of Applied Biomechanics
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• v.28 no.2
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• pp.87-92
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• 2018

Objective: The purpose of this study was to investigate the factors affecting two kinds of bat swing behavior through kinematic analysis. Method: A total of 32 high school baseball players participated in this study. The ball was placed on the tee-ball in a position where the subject could easily swing and the standard bat swing was performed as quickly and as accurately as possible using aluminum bats and wooden bats. Results: The aluminum bat showed a rapid swing speed of about 1.79 m/sec compared to the wooden bat. The speed of the batted ball was found to be significantly greater for the aluminum bat than for the wooden bat. In addition, although the difference between the shoulder-pelvis rotation angle according to the type of bat was not indicated, there was a statistically significant difference between the aluminum bat and the wooden bat in terms of the rotational angular velocity. Conclusion: Even though the results can explain the difference between the bat swing speed and the speed of the batted ball depending on the bat's material, it is difficult to explain the difference depending on the type of bat at the shoulder-pelvis rotation angle. However, shoulder-pelvic rotation angular velocity appears to be higher for the aluminum bat, and the differences in the type of bat is considered to be related to the batting swing factor.

• Korean Journal of Applied Biomechanics
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• v.23 no.2
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• pp.91-97
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• 2013

The purpose of this study was to compare the effect of a new warm-up condition, overloaded arm weights (721 g each arm, [OA]), on the bat speed during warm-up and immediately after warm-up with traditional warm-up conditions such as no-extra mass warm-up (control condition, [CO]) and overloaded bat warm-up (885 g donut on a bat, [OB]) conditions. Twenty male subjects who had competitive baseball experience participated in this study. Electromagnetic motion capture system was used to capture body segment motions. Results indicated that the OB showed significantly slower bat speed than the CO and OA did during warm-up (p<.05) and the bat speeds of OA and OB were similar. There was no main effect of different types of warm-up condition on the bat speed at post-warm-up swings. However, the first trial immediately after the OA and OB showed significant slower than the later trials (p<.05). Conclusively, the overloaded arm weights and overloaded bat did not show statistical superiority than the standard warm-up conditions in the deck circle and recovery time more than 3 minutes after loaded warm-up is recommended.

• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1421-1428
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• 2013

In this paper, we would like to test whether the hit at a particular bat has a dependency with the hitting results at the previous bats in professional baseball games. For this purpose, we used the 2011 Korean Baseball League data. We find out that the hitting percentage at a particular bat has no dependency with the hit at the previous bat, after reviewing the conditional probability of hit at each bat and the lift. From the independence test of hits at consecutive bats, and hit at a particular bat with no hits at previous bats, we can conclude that hits at particular bats are not dependent on the hits at previous bats in most cases. Hence, we can safely conclude that a hit at a particular bat is statistically independent from the hits at the previous bats.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.3
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• pp.506-514
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• 2020

Objective: We tested the hypothesis that increasing dietary copper (Cu) to gravid ewes would enhance brown adipose tissue (BAT) thermogenesis in their offspring. Methods: Twin-bearing ewes were assigned on d 70 of gestation to diets containing 3, 10, or 20 ppm dietary Cu (n = 8 per group). Twin lambs were assigned at birth to a cold (6℃) or warm (28℃) environmental chamber for 48 h. Blood was collected from ewes and from lambs and perirenal BAT was collected after 48 h in the environmental chambers. Results: Prenatal Cu exposure increased ewe plasma triiodothyronine (T₃) and thyroxine concentration (T₄) (p<0.01) but prenatal Cu exposure had no effect on lamb plasma concentrations of T₃, T₄, glucose, or nonesterified fatty acid concentration (p≥0.08). The high level of prenatal Cu exposure depressed 48-h rectal temperature (p = 0.03). Cold exposure decreased BAT norepinephrine (NE) and increased BAT dopamine (p≤0.01), but prenatal Cu exposure had no effect on BAT cytochrome C oxidase activity or BAT NE or dopamine (p≥0.07). However, BAT of lambs from high-Cu ewes maintained higher uncoupling protein-1 (UCP1) gene expression than BAT of lambs from low- and medium-Cu ewes following warm or cold exposure in environmental chambers (p = 0.02). Cold exposure caused near depletion of BAT lipid by 48 h (p<0.001), increased BAT cytochrome c oxidase activity (p<0.01), and depressed plasma fatty acid concentrations (p<0.001). Conclusion: Although prenatal Cu exposure increased BAT UCP1 expression during warm and cold exposure, prenatal cold Cu exposure depressed 48-h rectal temperature. Cold exposure decreased BAT lipid content by over 80% and decreased lamb plasma fatty acid concentration by over 40%, indicating that fuel reserves for thermogenesis were nearly depleted by 48 h of cold exposure.

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.1
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• pp.21-28
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• 2021

Purpose Brown fat, or brown adipose tissue (BAT), is involved in non-shivering thermogenesis and creates heat through glucose metabolism. BAT activation occurs stochastically by internal factors such as age, sex, and body mass index (BMI) and external factors such as temperature and environment. In this study, as a retrospective, electronic medical record (EMR) observation study, statistical analysis is conducted to confirm BAT activation and various factors. Materials and Methods From January 2018 to December 2019, EMR of patients who underwent PET/CT scan at the National Cancer Center for two years were collected, a total of 9155 patients were extracted, and 13442 case data including duplicate scan were targeted. After performing a univariable logistic regression analysis to determine whether BAT activation is affected by the environment (outdoor temperature) and the patient's condition (BMI, cancer type, sex, and age), A multivariable regression model that affects BAT activation was finally analyzed by selecting univariable factors with P<0.1. Results BAT activation occurred in 93 cases (0.7%). According to the results of univariable logistic regression analysis, the likelihood of BAT activation was increased in patients under 50 years old (P<0.001), in females (P<0.001), in lower outdoor temperature below 14.5℃ (P<0.001), in lower BMI (P<0.001) and in patients who had a injection before 12:30 PM (P<0.001). It decreased in higher BMI (P<0.001) and in patients diagnosed with lung cancer (P<0.05) In multivariable results, BAT activation was significantly increased in patients under 50 years (P<0.001), in females (P<0.001) and in lower outdoor temperature below 14.5℃ (P<0.001). It was significantly decreased in higher BMI (P<0.05). Conclusion A retrospective study of factors affecting BAT activation in patients who underwent PET/CT scan for 2 years at the National Cancer Center was conducted. The results confirmed that BAT was significantly activated in normal-weight women under 50 years old who underwent PET/CT scan in weather with an outdoor temperature of less than 14.5℃. Based on this result, the patient applied to the factor can be identified in advance, and it is thought that it will help to reduce BAT activation through several studies in the future.

• Journal of Environmental Science International
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• v.23 no.3
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• pp.521-525
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• 2014

The Ussurian tube-nosed bat (Murina ussuriensis) is a registered endangered species that has not been observed in South Korea since 1960. We were able to capture three individuals of M. ussuriensis between 2011 and 2013 at Sobaeksan National Park. The discovery of this species was the first time within 50 years. To collect basic data on the M. ussuriensis, we analyzed the external morphology and ultrasound characteristics of the captured bats. The results indicated that M. ussuriensis weigh approximately 5.2 g, which is less than that of a typical small bat such as Pipistrellus abramus. The bat's wing-type ratio was determined to be 1.22 and classified as a broad and short wingspan type. The bat uses FM signals for ultrasound with a peak frequency of 92 kHz. The M. ussuriensis seems to be a forest-dwelling bat that preys on insects by maneuvering expertly within the complex mazelike structure of forests. In the future, further research on the hibernation and foraging sites of the bats is necessary to protect and monitor the species.

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.2
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• pp.48-54
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• 2021

Purpose In ¹⁸F-FDG PET/CT, the absorption of ¹⁸F-FDG due to the activation of Brown Adipose Tissue (BAT) greatly interferes with the discrimination of lymph node malignant metastasis. Warming the patient's body temperature before and after injection of ¹⁸F-FDG to prevent FDG absorption by BAT is a safe and non-pharmacological approach. The purpose of this study was to identify and select patients with a high potential for BAT activation in advance, and to investigate whether BAT can inhibit FDG absorption when the body temperature is raised for a short time by directly applying heat to the target patient. Materials and Methods Among the patients who underwent ¹⁸F-FDG PET/CT at the National Cancer Center from January 2020 to December 2020, 825 female patients (415 in the thermal group, 410 in the non-thermal group) under 50 years old were included. The thermal group was administered heat for 10 minutes before injection of ¹⁸F-FDG. For statistical analysis, the Z test comparing the ratios between the two groups was used, and logistic regression analysis was performed to correct for important variables (BMI, outdoor temperature, blood sugar) according to the results of the previous retrospective study. Results Among 825 patients, 19 patients with BAT activated (Thermal group: 5(1.2%), Non-thermal group: 14(3.41%)) accounted for 2.3% of the total. As a result of performing the Z test to compare the ratios between the two groups, the activation of BAT in the thermal group was significantly decreased (P=0.034). In the univariate logistic regression analysis, the activation of BAT was also decreased in the thermal group (OR: 0.34, P<0.05). In the multivariate results, BAT activation increased in patients younger than 45 years old (OR: 4.46, P<0.05) and outdoor temperature less than 13.2 degrees (OR: 9.97, P<0.05). BAT activation tended to decrease in the thermal group, but there was no significant difference (OR: 0.37, P=0.066). Conclusion We confirmed that the activation of BAT tends to decrease by 62.5% in the group subjected to the thermal method, and it will be of great help in preventing FDG absorption of BAT more effectively in the future.

• Archives of Plastic Surgery
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• v.48 no.4
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• pp.440-447
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• 2021

Background Brown adipose tissue (BAT) is a potential target for anti-obesity treatments. Previous studies have shown that BAT activation causes an acute metabolic boost and reduces adiposity. Furthermore, BAT and BAT-derived cell transplantation reportedly help treat obesity by regulating glucose and fatty acid metabolism. However, since BAT transplantation leads to whole-body weight loss, we speculated that earlier approaches cause a generalized and unnecessary fat tissue loss, including in breast and hip tissues. Methods We transplanted white adipose tissue-derived or BAT-derived preadipocytes prepared from C57BL/6 mice into one side of the inguinal fat pads of an obese mouse model (db/db mice) to examine whether it would cause fat loss at the peri-transplant site (n=5 each). The same volume of phosphate-buffered saline was injected as a control on the other side. Six weeks after transplantation, the inguinal fat pad was excised and weighed. We also measured the concentrations of glucose, triglycerides, fatty acids, and total cholesterol in the peripheral blood. Results BAT-derived preadipocytes showed abundant mitochondria and high levels of mitochondrial membrane uncoupling protein 1 expression, both in vivo and in vitro, with a remarkable reduction in weight of the inguinal fat pad after transplantation (0.17±0.12 g, P=0.043). Only free fatty acid levels tended to decrease in the BAT-transplanted group, but the difference was not significant (P=0.11). Conclusions Our results suggest that brown adipocytes drive fat degradation around the transplantation site. Thus, local transplantation of BAT-derived preadipocytes may be useful for treating obesity, as well as in cosmetic treatments.

• Animal Systematics, Evolution and Diversity
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• v.25 no.1
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• pp.87-93
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• 2009

Taxonomic studies on two bat species, Nyctalus furvus Imaizumi and Yoshiyuki 1968 belonging to the Vespertilionidae, and Tadarida teniotis (Rafinesque) 1814 belonging to the Molossidae collected at Busan, Korea were carried out. The former, which has been known as an endemic species in Japan, is newly recorded in the Korean fauna and the latter is a very rare species which has not been collected since 1928 (Ognev, 1928) until two females were collected at Busan in this study, although Kishida and Mori (1931) reported the occurrence of the latter with no collecting record. Due to the addition of the former to the South Korean bat fauna, the bat fauna is composed of a total of twenty one species and one subspecies belonging to three families.

• Development and Reproduction
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• v.1 no.1
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• pp.9-24
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• 1997

To investigate the process of spermiogenesis of the Korean eastern Daubenton's bat, Myotis daubentonii ussuriensis, the testis obtained from mature male bats was studied by transmission electron microscope and were based on the variety and diagnostic characters of cell organells. The results obtained from the present study are as follows. According to the differentiation of the cell organells, the spermiogenesis of the Korean eastern Daubenton's bat, M. d. ussuriensis, was divided into Golg, cap, acrosome, maturation and spermiation phases. Besides, these Golgi, cap, acrosome, and maturation phase were subdivided into the steps of early and late phases repectively and matruation phase was subdivided into step of early, mid and late phases. Therfore, the spermiogenesisof M. d. ussuriensis has been divided into a total of 11 phases. The chromatin granules began to condense at the early cap phase, regularized at the acrosome phase, and a perfect nucleus of sperm was formed at the maturation phase. The chromatoid body was occurred in the upper cytoplasm of nucleus at the early Golgi phase, and it was accurred the posterior cytoplasm of the nucleus at the early maturatio phase. The formation of sperm tail began to be develop in the early golgi phase, and completed at the spermiation phase. The fiber structure of middle piece was consisted of nine outer doublets and two central singlet microtubules and Nos. 1, 5, 6 and 9 in the outer dense were larger than the others(2, 3, 4, 7, 8).