• 한국의류산업학회지
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• 제20권5호
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• pp.600-607
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• 2018

Polypropylene fibers, while having many advantages such as light weight, sweat fast drying, water-repellent, drainage, thermal insulation, anti-static property has a drawback in dyeing. In recent years, the development of dyeable polypropylene fibers has expanded its value in the textile market. The purpose of this study is to fabricate composite spun yarns using polypropylene, acrylic, rayon and wool and to analyze tensile properties, uniformity characteristics, bending properties, hairiness, and surface shape according to the degree of fineness and blended ratio. The specimens consisted of 100% polypropylene spun yarn pp30, pp40 and ppa(pp/acrylic), ppr(pp/rayon), ppw(pp/wool), 5 altogether sed in this study. The results of the study are as follows. The breaking strength of polypropylene spun yarn blended with rayon and acrylic was higher than that of 100% polypropylene spun yarn. The polypropylene spun yarn is higher the fineness been shown to decrease the breaking strength and elongation. The bending properties of polypropylene spun yarns were in the order of ppa>ppr>pp40>pp30>ppw. The unevenness of ppw, ppr, and ppa was higher than pp40 and pp30. With the exception of ppw with crimp properties, pp30 and pp40 were found to have a hairiness index greater than ppr, ppa. In the microscopic photographs of polypropylene spun yarn, pp30, which had the highest hairiness index, was found to have a thick yarn and a large number of hairs, and ppw had hairs of 3 mm or more protruding elongated outwardly.

• Safety and Health at Work
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• 제12권2호
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• pp.244-248
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• 2021

Background: Sunburn is the main avoidable cause of skin cancer. Beach lifeguards spend many hours exposed to the effects of solar radiation during their work day, precisely at times of the year when levels of solar irradiation are highest. The aim of this study is to quantify the risk to beach lifeguards of sun exposure. Methods: A descriptive cross-sectional study was carried out in the Western Costa del Sol, southern Spain, during the summer of 2018. The research subjects were recruited during a skin cancer prevention course for beach lifeguards. All participants were invited to complete a questionnaire on their habits, attitudes, and knowledge related to sun exposure. In addition, ten were specially monitored using personal dosimeters for three consecutive days, and the results were recorded in a photoprotection diary. A descriptive analysis (mean and standard deviation for the quantitative variables) was performed, and inter-group differences were evaluated using the Mann-Whitney U test. Results: Two hundred fifteen lifeguards completed the questionnaire, and 109 met the criteria for inclusion in this analysis. The mean age was 23.8 years (SD: 5.1), 78.0% were male, 71.5% were phototype III or IV (Fitzpatrick's phototype), and 77.1% had experienced at least one painful sunburn during the previous summer. The mean daily personal ultraviolet exposure per day, the minimal erythema dose, and the standard erythema dose, in J/m², were 634.7 [standard deviation (SD): 356.2], 2.5 (SD: 1.4) and 6.35 (SD: 3.6), respectively. Conclusion: Beach lifeguards receive very high doses of solar radiation during the work day and experience correspondingly high rates of sunburn. Intervention strategies to modify their sun exposure behavior and working environment are necessary to reduce the risk of skin cancer for these workers and to promote early diagnosis of the disease.

• Radiation Oncology Journal
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• 제9권1호
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• pp.1-6
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• 1991

2-ODG가 쥐의 섬유육종(FSall)에 미치는 영향에 대한 연구로 에너지 신진대사는 체내에서의 $^{31}P$-자기공명 분광기를 이용하여 관찰하였고 세포 증식 능력은 유세포 분석기를 사용하여 연구하였다. 성장속도는 10개의 세포를 $C_3Hf/Sed$ 쥐의 발등에 이식한 후 3차원적으로 측정하여 관찰하였다. 2-DDG를 투여한 경우에는 이식후 12일에 복강내로 주사하였다. 이식후 12일의 종양의 평균 크기는 $250mm^3$이었다. Fsall종양의 성장속도는 semilog graph의 기울기와 종양의 doubling time으로 측정하였다. 2-DDG를 투여한 후 성장속도가 감속되었다. 5~12일 사이의 성장속도의 기울기가 0.828, 종양의 Idubling time이 0.84일이고 대조군에서는 13~28일 사이의 기울기가 0.218, doubling time이 3.2일인 반면 2-DOG 투여군에서는 성장속도의 기울기가 0.135이고 doubling time이 5.1일이었다. $^{31}P$-자기공명 분광기를 이용하여 2-DDG의 영향을 분석해 본 결과 2-DDG 투여후 종양증식 속도의 감속과 더불어 phosphornonester (PME)와 inorganic phosphate (Pi)의증가속도가 감소하였다. 이것은 2-DDG투여후 세포의 괴사가 감소하였다는 의미가 있다. 유세포 분석기를 이용하여 종양의 증식 능력을 분석한 결과는 2-DDG 투여후 5-phase와 G2+M phase의 DNA분포가 크게 증가하였다. 이것은 2-DDG투여후 세포가 좀더 방사선에 민감한 cycle로 진행함을 의미하는 것으로 해석할 수 있다. 이에 저자들은 2-DDG가 Fsall 종양세포에 미치는 흥미있는 결과를 토대로 방사선 치료에 미치는 영향과실제 이용 가능성에 대하여 더 연구하고자 한다.

• 천문학논총
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• 제27권4호
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• pp.311-316
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• 2012

Lyman break Galaxies are galaxies selected in the rest-frame ultraviolet. But, one important and missing information for these Lyman break galaxies is the amount of dust attenuation. This is crucial to estimate the total star formation rate of this class of objects and, ultimately, the cosmic star formation density. AKARI, Spitzer and Herschel are therefore the major facilities that could provide us with this information. As part of the Herschel Multi-tiered Extragalactic Survey, we have began investigating the rest-frame far-infrared properties of a sample of more than 4,800 Lyman Break Galaxies in the GOODS-North fiels. Most LBGs are not detected individually, but we do detect a sub-sample of 12 objects at 0.7 < z <1.6 and one object at z = 2.0. The ones detected by Herschel SPIRE have redder observed NUV-U and U-R colors than the others, while the undetected ones have colors consistent with average LBGs at z > 2.5. We have analysed their UV-to-FIR spectral energy distributions using the code cigale to estimate their physical parameters. We find that LBGs detected by SPIRE are high mass, luminous infrared galaxies. They also appear to be located in a triangle-shaped region in the $A_{FUV}$ vs. $logL_{FUV}$ diagram limited by $A_{FUV}$ = 0 at the bottom and by a diagonal following the temporal evolution of the most massive galaxies from the bottom-right to the top-left of the diagram. In a second step, we move to the larger COSMOS field where we have been able to detect 80 Lyman break galaxies (out of ~ 15,600) in the far infrared. They form the largest sample of Lyman break galaxies at z > 2.5 detected in the far-infrared. We tentatively name them Submillimeter Lyman break galaxies (S-LBGs).

• 한국환경보건학회지
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• 제39권5호
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• pp.465-473
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• 2013

Objectives: This study was undertaken to analyze Staphylococcus aureus from cultivation environments for agricultural products and to confirm antibiotic resistance and enterotoxin genes for the isolated S. aureus. Methods: A total of 648 samples were collected from apple, peach, ginseng and balloon flower farms. S. aureus was isolated from soil, agricultural water, personal hygiene elements (hands, gloves and clothes) and work utensils (boxes). Results: S. aureus was detected in a total of 25 samples and 72 strains were isolated. The resistance rate of the isolated S. aureus strains was confirmed at 33.3%, with 24 resistant strains among the total of 72. Fourteen different patterns types were found, and three pattern types (NV, OX, VA) were confirmed most frequently. As result of the detection of enterotoxin gene type, four gene types (sea: 1, sed: 4, seg: all isolated S. aureus, sei: all isolated S. aureus) were analyzed among a total of nine types. Conclusions: This study demonstrates that personal hygiene techniques should be properly managed, such as washing and sterilization before or after work, because agricultural contamination by S. aureus frequently developed through improper management.

• 한국환경과학회지
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• 제10권5호
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• pp.315-321
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• 2001

This study was conducted to estimate the decomposition capacity for organic matter by microbe of tidal flat sediments (Hajae, Dongjin and Mankyung). The decomposition rate constants (K') have been determined by Thomas slope method and compared with the values of each tidal flats. The decomposition rates of organic matter by microbe were initially very slow, but at the end of 12 hours, very sharply increased. The values of decomposition rate constant for Dongjin, Mankyung and Hajae tidal flat sediment were 1.364$day^{-1}$/, 1.080d$day^{-1}$ and 0.735$day^{-1}$, respectively. The decomposition rate constant of Dongjin tidal flat sediment which affected by livestock wastewater was higher than others. The decomposition quantity (mg/g/day) of organic matter by microbe of tidal flat sediments was 0.4mg/g/day for Dongjin, 0.36mg/g/day for Mankyung and 0.36mg/g/day for Hajae. The average of decomposition quantity was 0.37mg/g/day. To calculate purification capacity (kg/ha) of organic matter by microbe, we applied to two assumption ; 1) biological action by microbe is occur within 0.1cm under surface 2) specific gravity of sediment are 2.5g/$\textrm{cm}^2$. The purification capacity of organic matter by microbe of tidal flat sediment was calculated to 9.25kg/ha. The relationships between decomposition rate constant (K') and ignition loss (I. L), chemical oxygen demand by sediment (CO $D_{sed}$), total carbon(TC), silt and clay as index of organic matter were a high positive($R^2$=0.97~1.00).

• 천문학회보
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• 제37권1호
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• pp.74.2-74.2
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• 2012

We present [Fe II] 1.64 ${\mu}m$ imaging observations for jets and outflows from young stellar objects over the northern part (-24'${\times}$45') of the Carina Nebula, a typical evolved massive star forming region. The observations were performed with IRIS2 of Anglo-Autralian Telescope and the seeing was -1.5". Several jets and outflows features are detected at seven different regions, and one new Herbig-Haro Object is identified. The [Fe II] features have knotty and elongated shapes, and distribute around the triangular area formed by the star clusters Tr 14, Tr 15, and Tr 16, which contain many massive stars. The [Fe II] feature shows a highest detection rate (3.2 %) for the earliest stage YSOs, and the rate decreases as the stage evolves. The low detection rate (1.5 %) of [Fe II] features from the numerous YSOs seem to be related with the severe radiation environment of the Carina Nebula. The outflow rate shows reasonable relations with the physical parameters of the corresponding YSOs-derived from the SED fitting-such as the accretion luminosity, the stellar mass, the stellar age, the disk accretion rate, etc.

• 한국산림과학회지
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• 제10권1호
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• pp.5-6
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• 1970

한라산에 자라는 구상나무는 4개의 품종으로 구성되었다. 이 중에서 푸른 구상나무와 붉은 구상나무는 학계에 새로 보고하는 것이기에 그의 원기재(原記載)와 더불어 발표한다. 검 구상나무는 지리산에서 발견된바 있으나 한라산에서는 이번이 처음이다. 목련나무의 대목(大木)도 여기에서 처음발견 되었다.

• The Korean Journal of Physiology and Pharmacology
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• 제22권4호
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• pp.427-436
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• 2018

The objective of this study was to analyze the concurrent treatment effects of ursolic acid (UA) and low-intensity treadmill exercise and to confirm the effectiveness of UA as an exercise mimetic to safely improve muscle atrophy-related diseases using Sprague-Dawley (SD) rats with skeletal muscle atrophy. Significant muscle atrophy was induced in male SD rats through hind limb immobilization using casting for 10 days. The muscle atrophy-induced SD rats were group into four: SED, sedentary; UA, daily intraperitoneal UA injection, 5 mg/kg; EX, low-intensity (10-12 m/min, $0^{\circ}$ grade) treadmill exercise; and UEX, daily intraperitoneal UA injection, 5 mg/kg, and low-intensity (10-12 m/min, $0^{\circ}$ grade) treadmill exercise. After 8 weeks of treatment, endurance capacity was analyzed using a treadmill, and tissues were extracted for analysis of visceral fat mass, body weight, muscle mass, expression of muscle atrophy- and hypertrophy-related genes, and endurance capacity. Although the effects of body weight gain control, muscle mass increase, and endurance capacity improvement were inadequate in the UA group, significant results were confirmed in the UEX group. The UEX group had significantly reduced body weight and visceral fat, significantly improved mass of tibialis anterior and gastrocnemius muscles, and significantly decreased atrophy-related gene expression of MuRF1 and atrogin-1, but did not have significant change in hypertrophy-related gene expression of Akt and mTOR. The endurance capacity was significantly improved in the EX and UEX groups. These data suggest that concurrent treatment with low-intensity exercise and UA is effective for atrophy-related physical dysfunctions.

• 한국가축번식학회지
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• 제21권3호
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• pp.229-238
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• 1997

Chromosome condensation and swelling of the donor nucleus have been known as the early morphological indicators of chromatin remodelling after injection of a foreign nucleus into an enucleated recipient cytoplasm. The effects of non-preactivation and electrical preactivation of recipient cytoplasm, prior to fusing a donor nucleus, on the profile of nuclear remodelling in the nuclear transplant rabbit embryos were evaluated. The embryos of 16-cell stage were collected and synchronized to G1 phase of 32-cell stage. The recipient cytoplasms were obtained by removing the first polar body and chromosome mass by non-disruptive microsurgical procedure. The separated G1 phase blastomeres of 32-cell stage were injected into non-preactivated recipient cytoplasms. Otherwise, the enucleated recipient cytoplasms were preactivated by electrical stimulation and the separated G1 phase blastomeres of 32-cell stage were injected. After culture until 20h post-hCG injection, the nuclear transplant oocytes were electrofused by electrical stimulation. The nuclei of nuclear transplant embryos fused into non-preactivated and/or preactivated recipient cytoplasm were stained by Hoechst 33342 at 0, 1.5, 2, 4, 6, 8, 10 hrs post-fusion and were observed under an fluorescence microscopy. Accurate measurements of nuclear diameter were revealed with an ocular micrometer at 200$\times$. Upon blastomere fusion into non-preactivated recipient cytoplasm, a prematurely chromosome condensation at 1.5 hrs post-fusion and nuclear swelling at 8 hrs post-fusion were occurred as 91.6% and 86.1%, respectively. But the nuclei of nuclear transplant embryos fused into preactivated recipient cytoplasm, as o, pp.sed to non-preactivated recipient cytoplasm, were not occurred chromosome condensation and extensive nuclear swelling. Nuclear diameter fused into non-preactivated and preactivated recipient cytoplasm at hrs post-fusion was 30.2$\pm$0.74 and 15.2$\pm$1.32${\mu}{\textrm}{m}$, respectively. These results indicated that onset of unclear condensation and swelling which was associated with oocytes activation were critical steps in the process of chromatin swelling. Futhermore, complete reprogramming seemed only possible after remodelling of the donor nucleus by chromosome condensation and nuclear swelling.