• Journal of the Korean Dietetic Association
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• v.9 no.4
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• pp.307-315
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• 2003

This study was to investigate the relation of nutrients intake, health status, and bone mineral density in middle-aged women. Daily nutrients intake were analyzed by convenient method. The BMD of subjects were measured by Dual Energy X-ray Absorptiometry(DEXA). BMD was measured at the spine(vertebrae L2-L4) and femur(neck, Ward's triangle and trochanter). The nutrients intake of subjects were higher than recommended dietary allowances(RDA) except for calorie, iron, calcium, vitamin B1. Nutrients intake of vitamin A(p<0.05), iron(p<0.01), vitamin $B_2$(p<0.05), niacin(p<0.05), and vitamin C(p<0.05) between $\leq$49 yr group and $\geq$50 yr group. Mean daily intake of calcium was much less than the Korean RDA, 78.5% in $\leq$49 yr group and 77.3% in $\geq$50 yr group. 35.8% of the subjects under 50 years of age($\leq$49 yr group) and 77.4% of the subjects from 50 years up($\geq$50 yr group) were classified as osteopenia or osteoporosis. BMD of L2-L4 were positively correlated with height(p<0.05), weight(p<0.05) and BMI(p<0.05). BMD of femoral neck was positively correlated with BMI(p<0.05), BMD of Ward's triangle was positively correlated with weight(p<0.001). But BMD of L2-L4 and femoral neck were negatively correlated with age(p<0.05), menarche(p<0.05). BMD of Ward's triangle was negatively correlated with age(p<0.001). The BMD of L2-L4 were positively correlated with animal protein(p<0.05), calcium(p<0.05) and iron(p<0.05). The BMD of femoral neck was positively correlated with animal protein(p<0.05). The BMD of Ward's triangle was positively correlated with animal protein(p<0.001) and iron(p<0.001). The above results suggest that it should be difficult to prevent middle-aged women's bone destruction through nutrients intake. Further investigation is necessary to prove the mutual relations between BMD, exercise, and calcium intake. Therefore, middle-aged women will need proper exercise as well as Ca supplementation in order to prevent osteoporosis with aging.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.634-639
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• 2006

In order to develop a disease-resistant root stock for the growth of watermelon, an efficient regeneration system of the gourd(Lagenaria leucantha Duch.) inbred line GO701-2 via organogenesis was established in this experiment. Using proximal parts of cotyledon explant excised from germinated seedling in vitro, maximum adventitious shoot formation (39%) was achieved on MS medium where cytokinin (BA) and auxin (IAA) were added at a concentration of 3mg/L and 0.1mg/L, respectively. Roots of the elongated shoots were successfully formed on MS medium without adding any plant growth regulators. The cucumber CsGolS1 gene known as a resistance gene against biotic and abiotic stresses, was constructed into the binary vector pBI121 under the control of CaMV 35S promoter. When the gene was introduced into the genome of gourd by Agrobacterium-mediated transformation, putative transgenic plants were obtained with the transformation efficiency of approximately 20 percent.

• Polymer(Korea)
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• v.32 no.1
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• pp.13-18
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• 2008

For the evaluation of brominated flame retardants included in polymeric electronic devices, we investigated the extraction methods and solvent systems for four different types of polymers of PC (polycarbonate), PP (polyropylene), PET (poly(ethylene terephthalate)) and PBT (poly(butylene terephthalate)) using different solvent systems of hexane/acetone, THF, toluene, and THF/toluene. In order to compare the extraction efficiency of different methods and solvent systems, the deca-BDE (decabromo diphenyl ether) flame retardant was included in PC, PP, PET and PBT systems and subsequently extracted by soxhlet, ultrasonic, accelerated solvent, microwave and supercritical fluid extraction methods. The amount of the extracted flame retardant was monitored to evaluate the extraction efficiency. The ultrasonic extraction method was found not to be acceptable as an extraction method for the polymer systems mainly due to a low salvation efficiency of the organic solvents. Soxhlet, accelerated solvent and microwave extraction methods exhibited over 80% of extraction efficiency for toluene. The supercritical fluid extraction method, which has been used as an extraction method for flame retardants in polymers, showed the extraction efficiencies of ca. 100% for PC and PP in the optimal extraction conditions of $60^{\circ}C$ and 120 bar.

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.554-564
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• 1994

세균이 세포내 공생하는 xD strain과 모 세포주인 tD strain Amoeba proteus의 열충격 대응의 차이를 알아 보기 위하여 방사선 동위원소로 표지된 아미노산을 Ca2+_less Chalkley's 용액에서 음작용 경로를 통하여 90분 동안 흡수하게 하고, 저온 및 고온 스트레스에 대하여 새로 합성되는 스트레스 대응 단백질의 양상을 1, 2차원 전기영동 및 자기방사 사진법에 의해서 비교하였다 저온(10"C) 충격에 대응하여 아메바는 두 strain 모두 56.0 kDa, pl 6.0 단백질을 강하게 발현하였으며, xD strain에서는 tD strain과 달리 저온 충격 초기에 66 0 kDa, pl 5.5 단백질의 발현이 중단되었다. 한편 고온(33"C) 열충격에 대하여 두 strain 아메바에서 모두 10여종의 단백질이 새합성되는 것으로 확인되었으며, tD 아메바에는 이들 단백질의 새합성이 완만하게 이루어지는데 비하여 xD 아메바에서는 그중 66.0 kDa 단백질이 고온 대응 단백질로서 신속하게 새합성되는 것으로 나타났다. 이외에도 2차원 전기 영동 분석을 통하여 열충격에 의해서 발현이 촉진되는 다수의 단백질들을 탐지하였다 탐지된 아메바의 열충격 단백질은 분자량에 따라 hsp100군 2종, hsp90군, 3종, hsp70군 및 hsp60군 각 1종, 그리고 small csp군 4종으로 분류해 볼 수 있었다 두 분석의 결과를 종합해 보면 tD 아메바에는 저온 및 고온 충격에 대하여 열충격 단백질의 합성이 완만하게 상승하는 데 비하여 xD strain에서는 신속하게 이루어졌다. 이상의 결과로 보아 아메바의 세포내 공생 세균은 숙주의 열충격 대응기작에 변화를 야기한 것으로 판단된다한 것으로 판단된다. 10mg과 20mg의 estrogen 처리구 사이에 유두 직경, 길이 그리고 용적의 증가량에 있어서는 차이가 없었다. 10mg 및 20mg의 estrogen 처리는 초발정일령을 각각 20일 및 124일 단축시켰다. 전체적으로 이러한 결과는 송아지에 estradiol의 삽입은 성장과 유선 발달을 촉진시키고 초발정일령을 단축시킬수 있다는 것을 강력하게 지적한다. 일치하지 않으므로 더욱 정밀한 조사를 실시하여 분류학상의 위치를 정확히 밝혀 볼 필요가 있을 것으로 생각되었다.연한 도구이자 정신활동으로 보게함으로써, 주제 및 연구방법에서 획일성보다 다양성과 창조성이 강조되고 있다. 그리고 연구에 있어서 주제 의 다양성을 통해 보다 현실생활에 밀접하게 연결되어야 할 필요성은 학문이나 과학의 사회 성에 대한 새로운 인식을 가져다 주고 있다. 이러한 지리교육과정의 좌표의 변화된 측면들 을 고려하여, 지리교육과정의 새로운 방향은 다음의 세가지로 모색될 수 있다. 첫째, 爭點中 心 地理敎育課程이다. 사회쟁점에 대한 접근은 쟁점의 이해와 문제해결에의 지리적 관점의 활용을 통해 학습내용의 시사성과 사실성을 높힐 수 있다. 이때 문제해결능력을 통해 현대 시민의 자질 및 능력을 기를 수 있음은 물론, 다른 한편으로 실제세계 즉 학생의 실생활, 사 회, 국가, 세계에서 일어나는 일들과의 관련성을 갖게 함으로써, 내적 동기화와 외적인 자극 을 강력하게 결합할 수 있을 것이다. 이는 개인적 유관적합성과 사회적 유관적합성을 동시 에 확보하는 데 유리할 것이다. 둘째, 思考中心 地理敎育課程이다. 지리교육은 학생들을 지 식 및 기능의 숙달자가 되도록 할 것이 아니라 기본적 문장해독력의 수준을 넘어 능력있는 사고자로 길러내는 것을 목표로 하여야 한다.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.1-8
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• 2006

The purpose of this study was to evaluate normalized jerk according to shoes, slope, and velocity during walking. Eleven different test subjects used three different types of shoes (running shoes, mountain climbing boots, and elevated forefoot walking shoes) at various walking speeds(1.19, 1.25, 1.33, 1.56, 1.78, 1.9, 2, 2.11, 2.33m/sec) and gradients(0, 3, 6, 10 degrees) on a treadmill. Since there were concerns about using the elevated forefoot shoes on an incline, these shoes were not used on a gradient. Motion Analysis (Motion Analysis Corp. Santa Rosa, CA USA) was conducted with four Falcon high speed digital motion capture cameras. Utilizing the maximum smoothness theory, it was hypothesized that there would be differences in jerk according to shoe type, velocity, and slope. Furthermore, it was assumed that running shoes would have the lowest values for normalized jerk because subjects were most accustomed to wearing these shoes. The results demonstrated that elevated forefoot walking shoes had lowest value for normalized jerk at heel. In contrast, elevated forefoot walking shoes had greater normalized jerk at the center of mass at most walking speeds. For most gradients and walking speeds, hiking boots had smaller medio-lateral directional normalized jerk at ankle than running shoes. These results alluded to an inverse ratio for jerk at the heel and at the COM for all types of shoes. Furthermore, as velocity increased, medio-lateral jerk was reduced for all gradients in both hiking boots and running shoes. Due to the fragility of the ankle joint, elevated forefoot walking shoes could be recommended for walking on flat surfaces because they minimize instability at the heel. Although the elevated forefoot walking shoes have the highest levels of jerk at the COM, the structure of the pelvis and spine allows for greater compensatory movement than the ankle. This movement at the COM might even have a beneficial effect of activating the muscles in the back and abdomen more than other shoes. On inclines hiking boots would be recommended over running shoes because hiking boots demonstrated more medio-lateral stability on a gradient than running shoes. These results also demonstrate the usefulness of normalized jerk theory in analyzing the relationship between the body and shoes, walking velocity, and movement up a slope.

• Korean Journal of Materials Research
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• v.3 no.5
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• pp.443-450
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• 1993

Self-alignment gatc Schottky contact structure on Si- implanted GaAs was formed by plasma enhanced chemical vapor dcposirion. Tungsten nitride thin films (ahclut 1600$\AA$) \vcre dopositcd on GaAs at $350^{\circ}C$ in order to fahricarc GaAs 1Cs and ttwn rapidly annealed at $750^{\circ}C$ to $900^{\circ}C$. Thermal charac tcristics of PECVD)-$W_{67}N_{43}$/GaAs structure were investigated by X-ray diffraction, photolumintesccnce. and optical deep level transient specrroscopy. Results revealed that $W_{67}N_{33}$ gate was more thermally sta ble with GaAs substrate than W gate and Si atoms implanted In $W_{67}N_{33}$/GaAs structure became morr active than those In W/GaAs after annealing. I-V characteristics of $W_{67}N_{33}$/GaAs diod c exhibired a nearly ideal diode behavior. The termal stability of $W_{67}N_{33}$/GaAs diode was better than that of W/GaAs diode with the post annealing at temperatures from 800 to $900^{\circ}C$ for 20s without As overpressure.

• Journal of Pharmaceutical Investigation
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• v.26 no.1
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• pp.33-41
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• 1996

In order to study the effect of phenobarbital(PB) on the hepatic transport of diltiazem(DTZ), $Ca^{2+}$ channel blocker, we used isolated hepatocytes of rat which was intraperitoneally pretreated with phenobarbital sodium(75 mg/kg) for four days once a day. For the isolation of rat liver cells, a modification of the two step procedure of Seglen was used. DTZ was dissolved in incubation buffer to the final DTZ concentrations of 200, 400, 600, 800 and 1000 ng/ml in order to elucidate the uptake characteristics of DTZ by hepatocytes. Reactions were stopped at 10, 20, 30, 45, 60, 90, 120 and 300 sec. The initial velocity was determined by disappearance of diltiazem in the hepatocyte suspension. On the other hand, to determine the effect of PB on the in vitro hepatic intrinsic clearance of DTZ we obtained the metabolism rates of DTZ in the control and the PB-pretreated rat hepatocyte at various time intervals. According to pretreatment with PB, the size of hepatocyte and the amount of protein per $10^6$ cells were significantly (p<0.01) increased from $26.92{\pm}0.1364\;m$ to $35.31{\pm}1.00\;m$ and from $468{\pm}6.5\;{\mu}g/10^6$ cells to $628.8{\pm}12.1{\mu}g/10^6$ cells, respectively. In the case or hepatic uptake of diltiazem, $K_m$ was not different in the normalization by cell numbers and increased from $2.90\;{\mu}M\;to\;13.89\;{\mu}M$ in the normalization by protein amount. $V_max$ was increased regardless of normalization by protein amount and cell numbers, from $1.21\;{\mu}mole/min \;{\cdot}\;mg\;protein\;to\;3.96\;{\mu}mole/min\;{\cdot}\;mg\;protein\;and\;from\;2.38\;{\mu}mole/min\;{\cdot}\;10^6\;cells\;to\;2.83\;{\mu}mole/min\;{\cdot}\;10^6\;cells$, respectively. The in vitro hepatic intrinsic clearance of DTZ was significantly (p<0.01) increased from $0.640{\pm}0.038\;ml/mim\;{\cdot}\;10^6\;cells\;to\;2.385{\pm}0.212\;ml/min\;{\cdot}\;10^6\;cells$ due to PB-pretreatment. These results suggest that the uptake of DTZ by hepatocyte is extremely fast and PB enhances the hepatic intrinsic metabolic clearance of DTZ.

• Journal of Microbiology and Biotechnology
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• v.24 no.4
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• pp.489-496
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• 2014

High levels of extracellular xylanase activity (211.79 IU/mg) produced by Paenibacillus sp. NF1 were detected when it was submerged-cultured. After three consecutive purification steps using Octyl-Sepharose, Sephadex G75, and Q-Sepharose columns, a thermostable xylanase (XynNF) was purified to homogeneity and showed a molecular mass of 37 kDa according to SDS-PAGE. The specific activity of the purified XynNF was up to 3,081.05 IU/mg with a 14.55-fold purification. The activity of XynNF was stimulated by $Ca^{2+}$, $Ba^{2+}$, DTT, and ${\beta}$-mercaptoethanol, but was inhibited by $Fe^{2+}$, $Zn^{2+}$, $Fe^{2+}$, $Cu^{2+}$, SDS, and EDTA. The purified XynNF displayed a greater affinity for oat spelt xylan with the maximal enzymatic activity at $60^{\circ}C$ and pH 6.0. XynNF, which was shown to be cellulose-free, with high stability at high temperature ($70^{\circ}C-80^{\circ}C$) and low pH range (pH 4.0-7.0), is potentially valuable for various industrial applications. The enzyme hydrolyzed oat spelt xylan to yield mainly xylooligosaccharides (95.8%) of 2-4 degree of polymerization (DP2-4). Moreover, the majority of the xylooligosacharides (DP2-4) products was xylobiose (61.5%). The thermostable xylanase (XynNF) thus seems potentially usefull in the production of xylooligosaccharides.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.599-607
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• 2000

In this research, ${NH_4}^+-N$ and ${PO_4}^{3-}-P$ in wastewater were removed by crystallization. Nitrogen and phosphate have been regarded as key nutrients in the eutrophication of rivers and lakes. Struvite, $MgNH_4PO_4{\cdot}6H_2O$, is insoluble in alkaline solutions. Fertilizer industry wastewater contains organic and nitrogen concentration of 330 mg/L and 550 mg/L, respectively. Nitrogen in this wastewater cannot be treated by conventional biological treatment without physicochemical pretreatment, because nitrogen concentration is relatively high compared to organic concentration. Magnesium ions used in this study were from bittern and commercial magnesium salts of $MgCl_2$ and $Mg(OH)_2$. Bittern obtained as a by-product of seasalt manufacture contains $8,000mg\;Ca^{2+}/L$ and $32,000mg\;Mg^{2+}/L$. Optimum initial pH was 10.5~11.0 and the reaction was complete or done in 2 min. Nitrogen removal efficiency using bittern, $MgCl_2 $ and $Mg(OH)_2$ (as source of $Mg^{2+}$) was 71 %, 81% and 83%. respectively. Phosphate removal efficiency was 99%, 98% and 93%, respectively. Therefore, bittern, $MgCl_2$ and $Mg(OH)_2$ can be efficiently used as $Mg^{2+}$ source for crystallization of nitrogen and phosphate. However, bittern is economically favorable $Mg^{2+}$ source for removing nitrogen and phosphate in wastewater.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.446-451
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• 1997

The primary alcohol groups of four kinds of polysaccharides (com starch, rice starch, sweet potato starch, and cellulose), with different structures and water solubilities, were oxidized to carboxyl groups using 2,2,6,6-tetramethyl-1-piperidine oxoammonium ion (TEMPO) at $25^{\circ}C$. The optimum pH, TEMPO content, and NaBr content for the TEMPO/hypobromite-catalyzed oxidation of the polysaccharides were $10.5{\sim}11.0$, 10 mmol/mol primary alcohol, and 0.49 mmol/mol primary alcohol, respectively. The oxidation degree for the primary alcohol group was more than 90% for all four kinds of the polysaccharides. The oxidation process greatly increased the water solubility of the polysaccharides. Water-insoluble polysaccharide such as cellulose became water-soluble to the extent of 8.42% (w/v). And also, the polysaccharides with very low water solubility (less than 0.10% (w/v)) such as com starch, rice starch, and sweet potato starch had high water solubility of approximately 45%(w/v). The gel-forming abilities with calcium ion were determined. The oxidized polysaccharides are new anionic polymers with unique structures that could have application as gums, gels, and films.