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91.
C. M. Lee J. H. Kim M. H. Kang K. D. Eom H. M. Park 《The Journal of small animal practice》2014,55(5):274-277
A seven‐month‐old, entire, male miniature schnauzer dog was referred with acute vomiting, inappetence and depression primarily as a result of a gastric foreign body (pine cones). During investigations, thoracic radiographs revealed increased volume of the right lung lobes, deviated cardiomediastinal structures and elevation of the heart from the sternum. Thoracic computed tomography revealed left cranial lung lobe hypoplasia and extension of the right cranial lung parenchyma across the midline to the left hemithorax. Branches of the right pulmonary vessels and bronchi also crossed the midline and extended to the left caudal lung lobe. These findings suggested that the right and left lungs were fused. In humans this finding is consistent with horseshoe lung, which is an uncommon congenital malformation. To the authors’ knowledge, this case represents the first report of such a pulmonary anomaly in a dog. 相似文献
92.
Sang-Bum Park Min Lee Dong-Won Son Sang-Min Lee Jong-In Kim 《Journal of Wood Science》2014,60(1):74-79
Authors established a new manufacturing technology for crack-free carbonized boards by pressing and carbonizing the medium-density fiberboard. Industrialization of new functional carbon materials was performed by investigating the fundamental properties of the carbonized boards. To be used as a construction material, the carbonized board needs to satisfy the fire performance regulation. In this study, the carbonized boards were manufactured from medium-density fiberboard (c-MDF) at different temperatures and then fire performance including flame retardancy and smoke toxicity was analyzed using a cone calorimeter and noxious gas analyzer. The results show that as the carbonization temperature increases, weight loss ratio decreases and flame retardancy increases. In the c-MDF at 800 and 1000 °C, no external damage was observed after combustion. These c-MDFs satisfy the total heat release (standard below 8 MJ/m2) and heat release rate (standard below 200 kW/m2) regulations according to the Building Standard Law of Korea and Japan. In addition, the c-MDFs showed the lower total smoke release (TSR, 0.213 m2/m2) than that of virgin MDF (94.281 m2/m2). The c-MDF at 800 and 1000 °C were, therefore, classified as a class III flame retardancy material and can be used as indoor finishing material. 相似文献
93.
Jong-Hak Yun Katsuhiro Nakao Ikutaro Tsuyama Motoki Higa Tetsuya Matsui Chan-Ho Park Byoung-Yoon Lee Nobuyuki Tanaka 《Journal of Forest Research》2014,19(1):174-183
To quantitatively assess future change of evergreen broad-leaved tree species’ distributions in human-disturbed landscapes of the Korean Peninsula under climate change, potential habitats (PHs) were projected for four important evergreen broad-leaved tree species (Quercus acuta, Castanopsis sieboldii, Machilus thunbergii, and Neolitsea sericea) by species distribution models (SDMs). The distribution data (presence/absence) of the target species in Korea and Japan were used as response variables for SDMs, and climatic data were used as explanatory variables. Three general circulation models under A2 emission scenarios were used as future climate scenarios for the years 2070–2099. Potential habitats masked by land-use data (PHLUs) were projected to assess the impact of anthropogenic activities. Highly accurate SDMs were obtained for all the target species. The current PHs were decreased to 21–35 % by the anthropogenic activities. Future PHLUs for all the target species were projected to increase by 2.0–18.5 times of current PHLUs. These results suggest that all the target species are applicable as indicator species for monitoring in the Korean Peninsula, even if anthropogenic effects are incorporated. Variation of the increasing rate was caused by the differences in the response to temperature changes. M. thunbergii responded sensitively to the increase of minimum temperature of coldest month and had a largest increase in PHLUs under future climate. Therefore, M. thunbergii is considered to be most appropriate species for monitoring the changes of horizontal distributions above all focal evergreen broad-leaved tree species. 相似文献
94.
95.
Sang Kyu Park Sangho Roh Jong-Im Park 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):73-80
Various somatic cell nuclear transfer (SCNT) techniques for mammalian species have been developed to adjust species-specific procedures to oocyte-associated differences among species. Species-specific SCNT protocols may result in different expression levels of developmentally important genes that may affect embryonic development and pregnancy. In the present study, porcine oocytes were treated with demecolcine that facilitated enucleation with protruding genetic material. Enucleation and donor cell injection were performed either simultaneously with a single pipette (simplified one-step SCNT; SONT) or separately with different pipettes (conventional two-step SCNT; CTNT) as the control procedure. After blastocysts from both groups were cultured in vitro, the expression levels of developmentally important genes (OCT4, NANOG, EOMES, CDX2, GLUT-1, PolyA, and HSP70) were analyzed by real-time quantitative polymerase chain reaction. Both the developmental rate according to blastocyst stage as well as the expression levels CDX2, EOMES, and HSP70 were elevated with SONT compared to CTNT. The genes with elevated expression are known to influence trophectoderm formation and heat stress-induced arrest. These results showed that our SONT technique improved the development of SCNT porcine embryos, and increased the expression of genes that are important for placental formation and stress-induced arrest. 相似文献
96.
Hepatic cysteinesulphinate decarboxylase activity in fish 总被引:2,自引:0,他引:2
97.
Highly aligned ultrafine fibers of Poly (amide-co-imide) PAI (torlon)/Poly (trimellitic anhydride chloride-co-4, 4′-methylene dianiline) (PTACM) blends have been prepared by using mechano-electrospinning. Employing a mixed solvent system of DMSO and THF alongwith water coagulation bath as a medium, continuous fibers with improved mechanical properties have been obtained. The continuity of the fibers is strongly dependent on the solvent mixing ratio of DMSO and THF (6:4). Continuous fibers with the most uniform diameter are obtained when a 30 % of PAI and PTACM (1:1) resins by weight is used in the blending solution. The aligned fibers are further coated with silver nanoparticles using a one-step process by passing the electrospunned fibers through PEG solution and a silver precursor solution followed by reduction in a continuous process. The advantage of our method lies in a uniform silver coating on a single fiber that can be coated continuously on a larger length scale (~Km). The mechanical properties of these fibers are dramatically improved after their alignment. Better electrical conductivity is obtained for these fibers after they are coated with silver nanoparticles. The highly aligned silver decorated fibers utilizes a novel electroless continuous process using Polyethylene glycol (PEG), which shows good binding properties and can be used for various bio and electronic applications. 相似文献
98.
This study evaluated the potential application of an atmospheric plasma (AP) treatment as a pre-treatment for digital textile printing (DTP) of polyester (PET) fabrics and cotton, in order to determine its viability as an alternative to the usual chemical treatment. The surface properties of the AP-treated fabrics were examined through scanning electron microscopy (SEM) and contact angle, and the physical properties, such as electrostatic voltage and water absorbance, were tested. The properties of cotton and PET with the AP treatment were found to be dependent on number of repetitions and electric voltage. Although no remarkable surface differences were observed by SEM in the fabrics before and after treatment, the static contact angle of the PET after AP treatment was decreased from 85 ° to 24 ° at wave. In addition, the charge decay time decreased as the voltage and number of treatments increased. The absorption height of PET changed after exposure to 7 mm with increasing measurement time. The K/S with and without the AP pre-treated and DTP finished cotton was better than that with the usual chemical modification. In PET, the 0.5 kW and 1 time AP-treated specimen showed the highest K/S values. 相似文献
99.
Chang Soo Lee Kwan Han Yoon Jae Cheol Park Hong-Un Kim Young-Bin Park 《Fibers and Polymers》2014,15(7):1493-1499
Poly(ethylene terephthalate) (PET)/CaCO3 and PET/modified-CaCO3 (m-CaCO3) nanocomposites were prepared by melt blending. The morphology indicated that m-CaCO3 produced by reacting sodium oxalate and calcium chloride, was well dispersed in PET matrix and showed good interfacial interaction with PET compared to CaCO3. No significant differences in the thermal properties such as, glass transition, melting and degradation temperatures, of the nanocomposites were observed. The thermal shrinkage of PET at 120 °C was 10.8 %, while those of PET/CaCO3 and PET/m-CaCO3 nanocomposites were 2.9–5.2 % and 1.2–2.8 %, respectively depending on filler content. The tensile strength of PET/CaCO3 nanocomposite decreased with CaCO3 loading, whereas that of PET/m-CaCO3 nanocomposites at 0.5 wt% loading showed a 17 % improvement as compared to neat PET. The storage modulus at 120 °C increased from 1660 MPa for PET to 2350 MPa for PET/CaCO3 nanocomposite at 3 wt% loading, and 3230 MPa for PET/m-CaCO3 nanocomposite at 1 wt% loading. 相似文献
100.
Park Jong-Yoon Yu Young-Seok Hwang Soon-Jin Kim Chulgoo Kim Seong-Joon 《Paddy and Water Environment》2014,12(1):65-75
Suitable and practicable best management practices (BMPs) need to be developed due to steadily increasing agricultural land development, intensified fertilization practices, and increased soil erosion and pollutant loads from cultivated areas. The soil and water assessment tool model was used to evaluate the present and future proper BMP scenarios for Chungju dam watershed (6,642 km2) of South Korea, which includes rice paddy and upland crop areas. The present (1981–2010) and future (2040s and 2080s) BMPs of streambank stabilization, building recharge structures, conservation tillage, and terrace and contour farming were examined individually in terms of reducing nonpoint source pollution loads by applying MIROC3.2 HiRes A1B and B1 scenarios. Streambank stabilization achieved the highest reductions in sediment and T-N, and slope terracing was a highly effective BMP for sediment and T-P removal in both present and future climate conditions. 相似文献