• Journal of The Korean Association For Science Education
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• v.26 no.4
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• pp.492-501
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• 2006

Gender differences in TIMSS 2003 science achievement by item type, benchmark, and content area were examined by producing a Gender Differences Index (GDI) in this study. International trends identified that male students performed better than female students in TIMSS 2003 science achievement in all types of items. The overall achievement of Korean male students was better than Korean female students, especially in multiple-choice type items. Male students outperformed females in three benchmarks, including advanced, high, and intermediate international benchmark, but they did not outperform females in the low international benchmark when gender differences of the international average as well as the Korean average were taken into account. The results of the analysis of the international average and the Korean average by content area showed that gender differences were the greatest in earth science and smallest in chemistry. In life science, female students excelled when considering the international average while male students excelled when considering the average of Korean students' performance. In addition, the number of items in which male students outperformed females was larger in both factual knowledge and the conceptual understanding domain. Implications for reducing gender differences in science achievement in Korea based on the results were provided.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.3
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• pp.41-51
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• 2024

This study aimed to analyze the effects of ESG management activities of auto parts manufacturers on organizational trust, organizational immersion, and job satisfaction, and to examine the intermediate effects of organizational trust and organizational immersion between ESG management activities and job satisfaction. Research models and hypotheses were established by referring to the theoretical background and empirical analysis of the preceding studies, and 221 questionnaires were secured for members of Busan and Gyeongnam-based auto parts manufacturers C, E, G, and S for empirical analysis. The results of the study are as follows. First, energy saving, regional cluster construction, and compliance ethics management were statistically significant in identifying the relationship between ESG management activities and organizational trust. Second, in the analysis of the impact of ESG management activities on organizational immersion, compliance ethics management showed significant results (+). Third, the analysis of the relationship between organizational trust and job satisfaction showed a significant result of affection (+). Fourth, organizational immersion has been analyzed to have an effect on Jung (+) that is significant for job satisfaction. Finally, the analysis of the parameters of organizational trust and organizational immersion showed that both variables had a medium effect. In conclusion, it was an opportunity for auto parts makers to recognize that they can increase their members' job satisfaction by making efforts to increase trust and immersion in the organization through ESG activities.

• Journal of Radiation Industry
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• v.18 no.1
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• pp.35-42
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• 2024

Demand for RW transportation is expected to increase due to the continuous generation of RW from nuclear power plants and facilities, decommissioning of plants, and saturation of spent fuel temporary storage facilities. The locational aspect of plants and radiation protection optimization for the public have led to an increasing demand for maritime transportation, necessitating to apprehend the overseas and domestic current status. Given the potential long-term radiological impact on the public in the event of a sinking accident, a pre-transportation exposure assessment is necessary. The objective of this study is to investigate the overseas and domestic RW maritime transportation current status and overseas dose assessment cases for the public in sinking accident. Selected countries, including Japan, UK, Sweden, and Korea, were examined for transport cases, Japan and the U.S were chosen for dose assessment case in sinking accidents. As a result of the maritime transportation case analysis, it was performed between nuclear power plants and reprocessing facilities, from plants to disposal or intermediate storage facilities. HLW and MOX fuel were transported using INF 3 shipments, and all transports were performed low speed of 13 kn or less. As a result of the dose assessment for the public in sinking accident, japan conducted an assessment for the sinking of spent fuel and vitrified HLW, and the U.S conducted for the sinking of spent fuel. Both countries considered external exposure through swimming and working at seashore, and internal exposure through seafood ingestion as exposure pathway. Additionally, Japan considered external exposure through working on board and fishing, and the U.S considered internal exposure through spray inhalation and desalinized water and salt ingestion. Internal exposure through seafood ingestion had the largest dose contribution. The average public exposure dose was 20 years after the sinking, 0.04 mSv yr^-1 for spent fuel and 5 years after the sinking, 0.03 mSv yr^-1 for vitrified HLW in Japan. In the U.S, it was 1.81 mSv yr^-1 5 years after the sinking of spent fuel. The results of this study will be used as fundamental data for maritime transportation of domestic RW in the future.

• Journal of Korean Society of Forest Science
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• v.29 no.1
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• pp.20-53
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• 1976

For the purpose of detecting the capability of the trees to resist air pollution and of determining the tree species best suited for purification of polluted air, particularly with regard to $SO_2$ contamination, six following ornamental tree species were selected as experimental materials: i.e., Hibiscus syriacus L., Ginkgo biloba L., Forsythia koreana Nak., Syringa dilatata Nak., Larix leptolepis Gordon, and Pinus rigida Miller. The susceptiblities of the trees were observed and analyzed on the basis of area ratio of smoke injury spots to the total leaf area. The results of the experiments are as follows: I. The Susceptibilities to Sulfur Dioxide. (1) The decreasing order of tolerance to $SO_2$ by species was as follows: 1. Hibiscus syriacus 2. Ginkgo biloba, 3. Forsythia koreana, 4. Syringa dilatata, 5. Larix leptolepis, and 6. Pinus rigida. In general, Hibiscus syriacus and Ginkgo biloba can be grouped as the most resistant and Larix leptolepis and Pinus rigida as the least resistant and Forsythia koreana and Syringa dilatata as of intermediate resistance. (2) The sulfur content of the leaves treated by $SO_2$ increased in proportion to the increase of the concentration of the fumigation. The content in the coniferous species proved to be less than that of the broad-leaved species, but Ginkgo biloba proved to contain as much sulfur as broad-leaved species. (3) The earlier-stage leaves fumigated in June with the $SO_2$ concentration up-to-l-ppm showed that sulfur content increases in proportion to the increase of the concentration of the fumigation, but the difference between concentration was not so significant. (4) The later-stage leaves fumigated in October showed higher sulfur content than the earlier stage leaves, and a wider range of difference in sulfur content was detected among different concentrations. The limit of fumigation resulting in culmination of sulfur absoption in broad-leaved species, such as Syringa dilatata, Hibiscus syriacus, and Forsythia koreana proved to be around 0.6 ppm. (5) Due to the sprouting ability and the adventitious bud formation, the recovery from $SO_2$ fumigation was prominent in Hibiscus syriacus, Syringa dilatata, and Forsythia koreana. (6) The differences in the smoke spot color were recognized by species: namely, dirt-brown in Syringa dilatata, brilliant yellowish-brown in Pinus rigida and Ginkgo biloba, whitish-yellow in Hibiscus syriacus and reddish-brown in Forsythia koreana. (7) The leaf margins proved to be most susceptible, and the leaf bases of the mid-rib most tolerant. In both Ginkgo biloba and Larix leptolepis, the younger leaves were more resistant to $SO_2$ than the older ones. II. The ulfur Content of the Leaves of the Ornamental Trees Growing in the City of Seoul. (1) The sulfur contents in the leaves of the Seoul City ornamental trees showed a remarkably higher value than those of the leaves in the non-polluted areas. The sulfur content of the leaves in the non-polluted area proved to be in the following descending order: Salix pseudo-lasiogyne Leveille, Ginkgo biloba L., Alianthus altissima swingle, Platanus orientalis L., and Populus deltoides Marsh. (2) In respect to the sulfur contents in the leaves of the ornamental trees in the city of Seoul, the air pollution proved to be the worst in the areas of Seoul Railroad Station, the Ahyun Pass, and the Entrance to Ewha Womans University. The areas of Deogsu Palace, Gyeongbog Palace, Changdeog Palace, Changgyeong Park and the Hyehwa Intersection were least polluted, and the areas of the East Gate, the Ulchi Intersection and the Seodaemun Intersection are in the intermediate state.

• Parasites, Hosts and Diseases
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• v.28 no.1
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• pp.45-52
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• 1990

Intestinal histopathological changes due to infection with Echinostcma hortense (Trematoda) were studied in rats after experimental infection with the metacercariae. The metacercariae were obtained from the tadpoles of Rana nigrcmaculata, a second intermediate host infected in the laboratory. Total 18 albino rats(Sprague-Dawley) were given 200 matacercariae each and sacrificed on the day 1, 3, 7, 11, 22 or 44 post-infection(PI) Segments of- the small intestine at 1, 3, 5, 8 and 30 cm posterior to the pylorus(PTP) were rejected and studied histopathologically. 1. The flukes were seen to have intruded into the intervillous space in the upper small intestine at early stages(1∼3 days PI), however, they were located mainly in the intestinal lumen at later stages(7∼44 days PI) . The flukes were sucking and destroying the epithelial layers of villi with their oral and ventral suckers. 2. Histopathological changes of the intestine were recognizable in as early as 1∼3 days after infection, and the changes became severer as the infection progressed. 3. The intestinal mucosa was histopathologically characterized by villous atrophy and crypt hyperplasia throughout the infection period. Major villous changes were blunting, fusion, severe destruction and loss of epithelial layers of villi. Villous/crypt(V/C) height ratio was remarkably reduced from 3 : 1 in controls to 1 : 1 in severely infected animals. In the stroma of villi, inaamma- tory cell infiltrations, vascular congestion, edema, and/or fibrosis were recognized. The goblet cells were increased in number after 11 days PI. It was revealed in the present study that the pathological changes in the intestine of rats infected with E. hortense were chieay confined to the mucosal layer of the upper small intestine, however, the changes were very severe accompanying remarkable destruction of villi and loss of mucosal integrity, and persistent until 44 days PI.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.965-973
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• 2014

Three studies were conducted to investigate whether a chelated Cu can replace $CuSO_4$ as a growth promoter in pigs. In Exp. 1, a total of 240 piglets (Large White${\times}$Landrace, $7.36{\pm}0.10kg$) were randomly allocated to 1 of 3 treatments with 8 replicates and 10 piglets per pen. Treatments included a NRC control ($CuSO_4$, 6 mg/kg), two Cu supplementations from either $CuSO_4$ or $Cu(HMTBa)_2$ at 170 mg/kg. Pigs fed $Cu(HMTBa)_2$ were 6.0% heavier than pigs fed either the NRC control or 170 mg/kg $CuSO_4$ (p = 0.03) at the end of the experiment. During the 42 days of experimental period, pigs fed $Cu(HMTBa)_2$ gained 9.0% more (p = 0.01), tended to eat more feed (p = 0.09), and had better feed efficiency (p = 0.06) than those fed $CuSO_4$. Compared with the 6 mg/kg $CuSO_4$ NRC control, liver Cu was increased 2.7 times with 170 mg/kg $CuSO_4$ supplementation, and was further increased with $Cu(HMTBa)_2$ (4.5 times, p<0.05). In Exp. 2, a total of 616 crossbred piglets (PIC, $5.01{\pm}0.25kg$) were randomly allocated to 1 of 4 treatments with 7 replicates and 22 piglets per pen. Treatments included a NRC control (from $CuSO_4$), and three pharmaceutical levels of Cu (150 mg/kg) supplemented either from C$CuSO_4$, tri-basic copper chloride ($Cu_2[OH]_3C1$), or $Cu(HMTBa)_2$. Pigs fed $CuSO_4$ or $Cu(HMTBa)_2$ had better feed efficiency (p = 0.01) and tended to gain more (p = 0.08) compared with those fed the NRC control. Pigs fed $Cu_2[OH]_2C1$ were intermediate. Pigs fed $Cu(HMTBa)_2$ had the highest liver Cu, which was significantly higher than those fed ($Cu_2[OH]_3C1$) or the negative control (p = 0.01). In Exp. 3, a total of 1,048 pigs (PIC, $32.36{\pm}0.29kg$) were allotted to 6 treatments with 8 replicates per treatment and 20 to 22 pigs per pen. The treatments included a NRC control with 4 mg/kg Cu from $CuSO_4$, a positive control with 160 mg/kg Cu from $CuSO_4$, and incremental levels of $Cu(HMTBa)_2$ at 20, 40, 80, and 160 mg/kg. During the overall experimental period of 100 days, no benefit from 160 mg/kg $CuSO_4$ was observed. Pigs fed $Cu(HMTBa)_2$ had increased ADG (linear and quadratic, $p{\leq}0.05$) and feed efficiency (linear and quadratic, $p{\leq}0.05$) up to 80 mg/kg and no further improvement was observed at 160 mg/kg for the whole experimental period. Pigs fed 80 mg/kg $Cu(HMTBa)_2$ weighed 1.8 kg more (p = 0.07) and were 2.3 kg heavier in carcass (p<0.01) compared with pigs fed 160 mg/kg $CuSO_4$. In addition, loin depth was increased with increased $Cu(HMTBa)_2$ supplementation with pigs fed 80 mg/kg $Cu(HMTBa)_2$ had the greatest loin depth (p<0.05). In summary, $Cu(HMTBa)_2$ can be used to replace high $CuSO_4$ as a growth promoter in nursery and grower-finisher pigs.

• Clinical and Experimental Pediatrics
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• v.51 no.1
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• pp.73-77
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• 2008

Purpose : p16 gene, mapped to the 9p21 chromosomal region, has emerged as a candidate tumor suppressor gene in human neoplasm. It is an inhibitor of cyclin-dependent kinase and inhibits Rb phosphorylation. In a variety of tumors including childhood acute lymphoblastic leukemia (ALL), deletion and/or mutation of the p16 gene has been found. Despite their high frequency, the prognostic importance of p16 alterations is still controversial in ALL and has been reported to be either unfavorable or similar to that of other patients. We studied the correlation between loss of p16 protein confirmed by immunohistochemical staining and clinical outcomes of patients diagnosed as ALL. Methods : We performed an immunohistochemical staining for p16 protein in 74 cases of bone marrow biopsy slide initially diagnosed as ALL between January 1998 and December 2006. We reviewed the clinical manifestations, laboratory findings, treatment outcomes retrospectively. Results : Of 74 slides, 12 were negative for p16 protein. Seven were males and 5 were females with a median age at diagnosis was 5.8 (1.3-18.8) years. Initial WBC were 17,225 $(500-403,300)/{\mu}L$. By immunologic surface marker analysis, 7 patients were early pre-B CALLA (+) and 5 patients were T-cell ALL. Two patients of intermediate risk group had relapsed and died. Three patients had family history of breast cancer. Four patients died and overall survival rates were $53.5{\pm}18.7%$. Conclusion : Loss of p16 protein is supposed to be an independent risk factor of childhood ALL associated with poor outcomes. In clinical setting, the clinician must take into account p16 status, not only at the genomic but also at the protein level. Further clinical experience on thoroughly investigated cases will help a better understanding between p16 status and clinical outcomes.

• Journal of the Korean Geographical Society
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• v.43 no.3
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• pp.296-311
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• 2008

In order to examine the rates and factors of path widening in Mount Halla, the retreat of path sidewalls was monitored at 32 sites of Seongpanak Hiking Trail located between 875 m and 1,400 m in elevation. The mean rate of sidewall retreat for the period 2002-2008 is 50.6 mm, equivalent to 10.0 mm/yr. The retreat rate of frozen period is 19.3 mm/yr, while the rate of unfrozen period is 4.3 mm/yr. The latter is divided into the rainy and dry periods that exhibit the retreat rates of 5.9 mm/yr and 2.9 mm/yr, respectively. The retreat rate of sidewalls is also varied with seasons; winter shows the maximum rate of 42.2 mm/yr, while summer exhibits the minimum rate of 1.3 mm/yr. Spring and fall show the intermediate rates of 13.9 mm/yr and 6.4 mm/yr, respectively. Soil hardness and elevation are not closely related to the retreat rate of sidewalls, even though the retreat rate is larger at the north-faced sidewalls than the south-faced sidewalls during the frozen period. Pipkrake is likely to be the most important factor contributing to the path widening in that the retreat of winter months accounts for 76.7% of the total retreat. The hiking trail is placed under the climatic conditions which develop pipkrake in 85 days annually. In addition, it is usual to observe the path sidewall covered with pipkrake in the freezing month of December and the thawing months of March and April. On the other hand, deflation and rainsplash erosion are not important due to the weak wind speed and the forested trail. Rainwash is also insignificant in that the path has been almost paved to mitigate trampling effects. Although biological activity is not dominant, hikers cause a large retreat of sidewalls in the thawing months since they would walk on the sidewalls to avoid snow-melting pools on the path.

• Korean Journal of Poultry Science
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• v.29 no.1
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• pp.59-75
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• 2002

The present study was conducted to compare the disease resistance to fowl typhoid among White Leghorn (WL) known as possessing greater genetic resistance to Salmonella, Rhode Island Red (RIR) susceptible to the disease and their mating crossbreed, WL ${\times}$RIR. Also, it was carried out to compare fowl typhoid-resistance among Hyline white${\times}$Hyline brown(HwHb), Hw${\times}$lsa brown(Hwlb), Isa white${\times}$lb(Iwlb), Iw${\times}$ Hb(IwHb) and Ib ${\times}$ Iw(IbIw) in order to select crossbreed chickens which have disease resistance to fowl typhoid and simultaneously produce the brown eggs which our domestic consummers prefer There was no death of WL chickens challenged with Sal. gallinarum at each 2, 5 and 8 wk of age, while average 86.2 to 64.1% of RIR chickens tested died at the same challenge age during the test period of 2 weeks. Their maiting crossbreed, WL ${\times}$ RIR were intermediate between the two breeds. weight gains of tested chickens were significantly higher in WL and WL ${\times}$RIR without difference between them than RIR. In recovery rate of tested strain of Sal. gallinarum from braun, heart, fiver, spleen and cecum of chickens challenged, WL ${\times}$RIR fell between the other two breeds, with somewhat higher rate then WL but much lower then RIR. In the disease resistance determination test using HwHb, Hwlb, Iwlb, IwHb and IbIw$.$ crossbreed chickens experimentally infected with Sal. gallinarum, it was recognized that all of crossbreeds tested developed marked resistance to fowl typhoid, based on the results judged by the measurement parameters of mortality, weight gain, recovery rate of challenged strain of bacteria, and positive rate of agglutination antibody, and HwHb had a tittle higher disease resistance then ethers.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.27-32
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• 2010

This study was conducted to reclassify Anryong series based on the second edition of Soil Taxonomy and to discuss the formation of Anryong series distributed on the mountain foot slope. Morphological properties of typifying pedon of Anryong series were investigated and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon of Anryong series has brown (7.5YR 4/4) loam Ap horizon (0-22 cm), strong brown (7.5YR 4/6) cobbly clay loam BAt horizon (22-35 cm), strong brown (7.5YR 4/6) cobbly clay loam Bt1 horizon (35-55 cm), reddish brown (5YR 5/4) cobbly clay loam Bt2 horizon (55-82 cm), and brown (7.5YR 5/4) cobbly clay loam Bt3 horizon (82-120 cm). The typifying pedon has an argillic horizon from a depth of 22 to 120 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. It can be classified as Ultisol, not as Alfisol. It has udic soil moisture regime, and can be classified as Udult. Also that meets the requirements of Typic Hapludults. It has 18-35% clay at the particle-size control section, and have mesic soil temperature regime. Therefore Anryong series can be classified as fine loamy, mesic family of Typic Hapludults, not as fine loamy, mesic family of Ultic Hapludalfs. Anryong series occur on mountain foot slope positions in colluvial materials derived from acid and intermediate crystalline rocks. They are developed as Ultisols with clay mineral weathering, translocation of clays to accumulate in an argillic horizon, and leaching of base-forming cations from the profile for relatively long periods under humid and temperate climates in Korea.