• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.25-39
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• 1984

The author has sought to determine the time and the sequence of permanent teeth eruption in Korean children. The study group consisted of 15,671 healthy children (male 8,015 ; female 7,656) aged 5-13 years old who lived in Seoul or Cheongju. The results were as follows : 1. The eruption times of permanent teeth were 0.45 years earlier in females than in males. 2. The ages corresponding to $ER_{50}$ of permanent teeth were as follows : In Maxilla 1) central incisor was 7.37 yrs 2) lateral incisor was 8.50 yrs 3) canine was 10.83 yrs 4) 1st premolar was 10.30 yrs 5) 2nd premolar was 11.09 yrs 6) 1st molar was 6.49 yrs 7) 2nd molar was 12.79 yrs In Mandible 1) central incisor was 6.40 yrs 2) lateral incisor was 7.41 yrs 3) canine was 10.18 yrs 4) 1st premolar was 10.26 yrs 5) 2nd premolar was 11.15 yrs 6) 1st molar was 6.32 yrs 7) 2nd molar was 12.05 yrs 3. The eruption sequence of permanent teeth by Z-test was as follow: In Male 1st : Mandibular 1st molar, and Mandibular central incisor 2nd : Maxillary 1st molar 3rd : Maxillary central incisor 4th : Mandibular lateral incisor 5th : Maxillary lateral incisor 6th : Mandibular canine, Maxillary and Mandibular 1st premolar 7th : Maxillary canine 8th : Maxillary and Mandibular 2nd premolar 9th : Mandibular 2nd molar 10th : Maxillary 2nd molar In Female 1st : Mandibular 1st molar, and Mandibular central incisor 2nd : Maxillary 1st molar 3rd : Mandibular lateral incisor, Maxillary central incisor 4th : Maxillary lateral incisor 5th : Mandibular canine, Maxillary and Mandibular 1st premolar 6th : Maxillary canine 7th : Maxillary and Mandibular 2nd premolar 8th : Mandibular 2nd molar 9th : Maxillary 2nd molar 4. The corresponding permanent teeth in the mandible generally erupted earlier than the corresponding permanent teeth in the maxilla by an average of 0.73 years, but the mean eruption time of mandibular 1st premolars was almost the same as those of maxillary 1st premolars, and the mean eruption time of mandibular 2nd premolars was 0.06 years later than those of maxillary 2nd premolars. 5. There is no significant difference between left and right arch in the eruption time and sequence. 6. Generally, the ages of permanent teeth eruption tended to be earlier than those of Dr. Cha's data from 1963.

• Nuclear Engineering and Technology
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• v.52 no.6
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• pp.1099-1109
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• 2020

The performance of gadolinium burnable absorber (GdBA) for reactivity control in UO₂ and (U, Th)O₂ fuels and its impact on spent fuel characteristics was performed. Five fuel assemblies: one without GdBA fuel rod and four each containing 16, 24, 34 and 44 GdBA fuel rods in both fuels were investigated. Reactivity swing in all the FAs with GdBA rods in UO₂ fuel was higher than their counterparts with similar GdBA fuel rods in (U, Th)O₂ fuel. The excess reactivity in all FAs with (U, Th)O₂ fuel was higher than UO₂ fuel. At the end of single discharge burn-up (~ 49.64 GWd/tHM), the excess reactivity of (U, Th) O₂ fuel remained positive (16,000 pcm) while UO₂ fuel shows a negative value (-6,000 pcm), which suggest a longer discharge burn-up in (U, Th)O₂ fuel. The concentration of plutonium isotopes and minor actinides were significantly higher in UO₂ fuel than in (U, Th)O₂ fuel except for ²³⁶Np. However, the concentration of non-actinides (gadolinium and iodine isotopes) except for ¹³⁵Xe were respectively smaller in (U, Th)O₂ fuel than in UO₂ fuel but may be two times higher in (U, Th)O₂ fuel due to its potential longer discharge burn-up.

• Journal of Life Science
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• v.22 no.3
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• pp.298-305
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• 2012

The general term flavonoids is often used to categorize a family of natural compounds that are highly abundant in all higher plants, and which in recent years have attracted scientific interest as therapeutics. Lutein is a xanthophyll and one of 600 known naturally occurring carotenoids. It is found in green vegetables such as spinach and kale, and has been demonstrated to exert anti-inflammatory activities. However, its anti-allergic effect in the Th1/Th2 immune response is poorly understood. In this study, we attempt to determine whether lutein regulates inflammatory mediators in an ovalbumin (OVA)-induced murine asthma model. To address this, mice were sensitized and challenged with OVA, and then treated with lutein before the last OVA challenge. Administration of lutein significantly suppressed the OVA-induced airway hyper-responsiveness. It also resulted in a significant alleviation of the infiltration of inflammatory cells into the bronchoalveolar lavage. Additionally, lutein attenuated the increased expression of Th2 responses in OVA-challenged mice. These results demonstrate that lutein is a potent inhibitor that reduces Th2 immune responses. Furthermore, they show that the immunopharmacological function is mediated by a pathway that involves and is regulated by Th2 immune response.

• Journal of Acupuncture Research
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• v.34 no.2
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• pp.39-48
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• 2017

Objectives : In this study, we investigated the immunomodulatory and antioxidant effect of MOK, a pharmacopuncture medicine, in concanavalin A (Con A)-stimulated mouse splenocytes. Methods : Primary splenocytes were isolated from ICR mice. The splenocytes were treated with MOK extract (1.25, 2.5, 5, 10, and 20 mg/mL) for 30 min and then stimulated with Con A (200 ng/mL) for the indicated times. Cell viability of the splenocytes was measured using an MTT assay. The mRNA expression of Th1/Th2 cytokines ($IFN-{\gamma}$, IL-4, IL-10, and Foxp3) and antioxidant enzymes (HO-1 and MnSOD) was measured by RT-PCR. Results : Addition of MOK extract at 2.5, 5, and 10 mg/mL in Con A-stimulated splenocytes significantly decreased the production of $IFN-{\gamma}$ and significantly increased the expression of IL-4, IL-10, and Foxp3 mRNA. MOK extract also increased the mRNA expression of HO-1 and MnSOD in splenocytes. Conclusion : MOK extract modulated the Th1/Th2 immune response via the regulation of cytokine levels in splenocytes and exerted an antioxidant effect via the upregulation of antioxidant proteins.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.681-693
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• 2007

Background and Objective : Atractylodes japonica (AJ) is a commonly-used herbal medicine in Asian countries such as Korea, China and Japan. The present study was designated to evaluate the direct effects of AJ on helper T cell activities and on Th1/Th2 lineage development in vitro. Materials and Methods : Spleen cells from 8-week BALB/c mice were cultured in CR extracts containing medium without activation for 24 hours and with activation for 48 hours. CD4+ T cells were isolated and analyzed for mRNA expression levels of INF-$\gamma$, IL-4, T-bet and GATA-3 by RT-PCR and secretion cytokines levels of INF-$\gamma$, IL-2, IL-4, IL-5 and IL-10 by ELISA. Results : The results demonstrated that AJ had no mitogenic effects on unstimulated CD4+ T cells, but augmented CD4+T-cell proliferation upon activation with anti-CD3/anti-CD28 antibodies in a dose-dependent manner. AJ treatment significantly increased CD4+ T cell population and IFN-$\gamma$ expression was significantly enhanced, while IL-4 expression significantly decreased. In addition, in vitro Th1/Th2 polarization experiments revealed that AJ enhanced IFN-$\gamma$ secretion in Th1 cells, but reduced the IL-4 in Th2 cells in dose-dependent manner. Conclusion : These results suggest that AJ treatment could be a desirable alternative therapy for the prevention or correction of Th2 dominant pathological disorders, such as allergy and asthma.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.439-449
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• 2019

The purpose of this research was to evaluate the effects of different sowing dates on growth characteristics, seed productivity and feed value of triticale in Gyeongbuk province. The experiment was conducted from September 2015 to July 2017, using triticale "Joseong" cultivar of 150 kg of seed/ha and sown at 10 days intervals from different sowing dates ($30^{th}$ September, $10^{th}$, $20^{th}$ and $30^{th}$ October) in 2015 and 2016, respectively. The emergence date in the autumn season was 8 - 18 days after sowing in 2015 and 2016. The heading, flowering and maturing periods were the fastest on $30^{th}$ September compared to the other sowing dates. The average number of stem and panicle per unit area were 409.3 - 428.5 and 330.9 - 334.0 on $30^{th}$ September and $10^{th}$ October, which were higher than those sown on $20^{th}$ and $30^{th}$ October, 2015 and 2016, respectively (p < 0.05), and the average number of grain and kernel weight was 47.1 - 48.1 and 2.2 - 2.3 g on $30^{th}$ September and $10^{th}$ October, which were higher than the late sowing dates. In case of seed yield as affected by different sowing dates, the highest yield was found on the sowing plot of late September and $10^{th}$ October, which were 5,680 and 5,918 kg/ha, respectively (p < 0.05). However, the average CP content was 10.7%, CF content was 2.8% and TDN content was 85.3. In conclusion, $30^{th}$ September and $10^{th}$ October were the appropriate sowing dates for a forage self-sufficiency system in Gyeongbuk.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.1
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• pp.153-170
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• 1989

Recently, frequently using hyperbaric oxygen therapy is known for its effectiveness on the healing of problem wounds such as osteomyelitis, osteoradionecrosis and gas gangrenous wound etc. The main objectives of this study was to determine the best protocol of its application of hyperbaric oxygen therapy. Author used 238 rats (Sprague-Dawley strain) deviding into 2 Groups, experimental I group for skin and experimental II group for palatal mucosal ischemic wounds, and observed its effects by microscopically. The obtained results summarized as follows; 1. Severe infiltration of inflammatory cells was observed in initial stages of both control and experimental I group. The infiltration showed decreasing tendency at 5th day of experimental D, E, F group while at 8th day in control group In d, f of experimental II group showed decreasing tendency at 8th experimental day while at 12th day in control group. 2. Macrophages appeared at 2nd day in D of experimental I group while at 6th day in control group. In d, f of experimental II group appeared at 6th day while at 10th day in control group. 3. As to the proliferation of capillary blood vessels showed at 3-4 day in most of experimental I group severely while at 8th day in control group. In experimental II group, it was at 8th day and 12th day respectively. 4. The proliferation of fibroblasts showed rather rapider in experimental I group, at 4-6th day, while at 8th day in control group. In experimental II group, it was at 8th day and 12th day respectively. 5. As to the collagen formations, it was at 4th day in experimental I group while at 8th day in control group. In experimental II group, it was at 6th day and 10th day respectively. 6. 5 rats (2.0 %) in E group and 8 rats (3.4 %) in f group showed oxygen toxic reaction, such as unstable attitude and tremor, during the experiments. This hyperbaric oxygen animal experiments disclosed excellent effects on the ischemic wound healing and it is thought to be the best protocol of its application was on D group (2.5 ATM. and 2 hrs, exposure).

• Journal of Veterinary Clinics
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• v.20 no.3
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• pp.384-388
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• 2003

To establish the method of estrus induction using the injection of PGF$_2$$\alpha$ㆍ the 60 dairy cows treated by PGF$_2$$\alpha$ㆍ at 6, 8, 10, 12, 14, and 16 day of estrous cycle, recpectively. The plasma progesterone concentrations at day of injection of PGF$_2$$\alpha$ㆍ were $1.5\pm$1.3 (mean$\pm$SD) ng/ml at 6 days of estrous cycle, 3.7$\pm$1.4 ng/ml at 8 days, 6.5$\pm$1.8 ng/ml at 10 days, 7.9$\pm$2.0 ng/ml at 12 days, 6.5$\pm$2.5 ng/ml at 14 days, and 2.5$\pm$1.2 ng/m] at 16 days, respectively. The percentages of induction of estrus after PGF$_2$$\alpha$ㆍ treatment were 52.8% at 3th day after treatment, 21.7% at 4th day, 8.3% within 2th day, and ] 7.2% after 5th day, respectively. The percentages of cows conceived at first service after induction of estrus were 73.3% on 16 days of estrous cycle at treatment, 66.7% on 10 and 14 days, 63.3% on 8 and 12 days, and 53.3% on 6 day, respectively. The percentages of cows conceived on first service were 70.5% at 3th day after induction, 66.7% at 4th day and 65% at 5th day, respectively. These results suggest that the PGF$_2$$\alpha$ㆍ treatment at regressing stage of corpus luteum showed high induction of estrus and pregnancy rate, and there were high induction of estrus and pregnancy rate at 3th and 4th day after PGF$_2$$\alpha$ㆍ treatment.

• Journal of The Korean Association For Science Education
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• v.21 no.1
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• pp.102-113
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• 2001

In order to compare with the 6th and 7th science curricular for the inquiry skill elements in the elementary and secondary school, we divided skill domains into five classes which were process skill, step skill for inquiry instruction, inquiry activity skill, manipulative skill and breeding-farming skill. And then we investigated the kinds and frequencies for the inquiry skill elements of the 6th and 7th curricular in the elementary and secondary school. The results were as follows: 1. The total kinds of inquiry skill element showed 17 kinds in the 6th curriculum and 23 kinds in the 7th. Therefore, the 7th curriculum was higher 1.4 times than the 6th curriculum in the kinds of skill elements. 2. The total frequencies for the inquiry skill elements of the 6th curriculum were 408 and those of the 7th were 729. Therefore, the 7th curriculum was about 1.8 times as many as the 6th. 3. In the kinds of inquiry skill elements according to the school levels, the course of the elementary school showed 14 kinds in the 6th curriculum and 18 kinds in the 7th. The course of middle school showed 7 kinds in 6th and 16 kinds in 7th. The integrated science course of high school was 10 kinds in the 6th and 10 kinds in the 7th. The skill elements in four science curricular of the high school course showed total 11 kinds in the 6th and 21 kinds in the 7th. And then the kinds of inquiry skill elements of the 7th curriculum in the middle and high school course showed about 2 times as many as the 6th curriculum. In the school level, the increase of skill elements showed the highest in the middle school course, and then in the high school course. 4. The total skill elements from the elementary school to the high school in the 6th science curriculum showed 17 kinds and in the order from the highest to the lowest rates, such as experimenting 20%, observing 15%, interpreting and analyzing data 13%, investigating 9%, measuring 7%, drawing a conclusion and assessment 7%, discussion 6%, communicating 5%, classifying 4%, recognizing problems and formulating hypothesis 4%, predicting 3%, designing and carrying out an experiment 3%, collecting and treating data 2%, manipulating skill 1%, modeling 0.5%, breeding and farming 0.3% and inferring 0.2%. 5. The total skill elements from the elementary school to the high school in the 7th curriculum appeared 23 kinds and in the order from the highest to the lowest rates, such as drawing a conclusion and assessment 31%, investigating 14%, collecting and treating data 8%, observing 7%, experimenting 7%, recognizing problems and formulating hypothesis 6%, interpreting and analyzing data 4%, measuring 3%, discussion 3%, manipulating skill 3%, modeling 3%, classifying 2%, project 2%, educational visits 1%, controlling variables 1%, predicting 1%, inferring 1%, operational definition 1%, communicating 1%, designing and carrying out an experiment 0.3%, breeding and farming 0.3%, applicating a number 0.2% and relating with time and space 0.2%. In the conclusion, the 7th curriculum was added 6 kinds of skill elements to the 6th curriculum, such as operational definition, applicating a number, relating with time and space, controlling variables, educational visits and project.

• School Mathematics
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• v.3 no.2
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• pp.233-248
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• 2001

In pthis aper, mathematical terms in 7th elementary mathematics curriculum(from now, in short, 7th curriculum)are reexamined critically. In 7th curriculum there are 123 terms, which seems to be selected cautiously But it is not sure. There are lots of evidences for selecting terms incautiously, Through these evidences, following conclusions are induced: (1) Terms were not selected strictly. There are many terms omitted in 7th curriculum, which are necessary for understanding mathematical concepts. (2) There were no rational principles for selecting terms in 7th curriculum. Any rational principles can not be found out among terms in 7th curriculum. (3) Mathematical terms and real life terms in 7th curriculum were not distinguished explicitly. There were some real life terms in 7th curriculum, which were significant for understanding mathematical concepts. But other real life terms which is significant also for understanding mathematical concepts were not contained in 7th curriculum.