• Journal of Korean society of Dental Hygiene
• /
• v.12 no.3
• /
• pp.521-531
• /
• 2012

Objectives : The aim of this study was to evaluate the relation between the state of dental health(number of natural teeth) and nutritional status of Korean elderly using Korean Dietary Reference Intakes, which was an objective standard for nutritional intake based on database of Korea National Health and Nutrition Examination Survey, large scale of sample obtained by the government. Methods : Complex sampling procedure was used to analyze the fourth data(2007-2009) of Korea National Health and Nutrition Examination Survey. When preparing planning file, the estimator of variance as a stratification variance (variance name : kstrata), population of survey unit as a cluster variance(variance name : PSU), and previous exam and nutritional related weighted as a weighted were analyzed by considering reproduced survey and nutritional related total weighted. Complex samples chi-square test was used to estimate the relation between number of natural teeth and inadequate intake and relation factors included in the model were analyzed by complex samples logistic regression analysis. Results : The group of edentulous had a higher risk to intake less nutrient, except calcium, riboflavin and vitamin C than recommended level comparing to reference group which had natural teeth more than 20(phosphate : OR=1.763; 95% CI=1.273-2.443, thiamine : OR=1.748; 95% CI=1.276-2.395, protein : OR=1.610; 95% CI=1.213-2.138). Conclusions : The number of teeth in Korean elderly over 65 years old had a relation with nutritional status in this investigation. Especially, intake level of nutrients was different between the edentulous group and the reference group. Therefore, dental health care is needed from young and middle age to keep health dental condition for through whole life as well as old age. Although the dental condition of the aged is not good, it is evitable to educate them about the relation between dental health and nutritional ingestion to take balanced nutrition, we think.

• Journal of Veterinary Clinics
• /
• v.31 no.1
• /
• pp.46-50
• /
• 2014

A 7-year-old spayed female Welsh corgi presented with a mass of the skull. The mass was diagnosed as multilobular bone tumor and surgically removed. To treat a large bone defect after the tumor removal, custom-made artificial bone fabricated by a 3-dimensional ink-jet printer was implanted in the defect. Follow-up computed tomography evaluation was performed for 4.3 years. The implant was well integrated with the skull and had covered the large bone defect during the follow-up period. Gradual degradation of the implant began 6 weeks after surgery. It provides an additional option for the treatment of large bone defect.

• Korean Journal of Soil Science and Fertilizer
• /
• v.30 no.2
• /
• pp.168-177
• /
• 1997

This study was carried out to find the physico-chemical properties of soils and the rice growth at the pilot project rice farm of Buchanan city, Liberia. The results were as follows. Soils were classified as Plinthic Ferralsols. Real tropical soils had an oxic B horizon of 30cm thick with diffused horizon boundaries. The surface soils have Ochric A horizon with low organic matter. Plinthite was distributed throughout the whole soil profile unevenly. Exposed to sun light, Plinthite was dried out, hardened, and developed irreversibly into ironstone. There were 286 termite hills in 20ha in the project area. The pH value of the termite hills was higher than that of the ordinary soil two units. Soils of the termite hills had higher contents of carbon, nitrogen, available phosphate and exchangeable bases, especially calcium(2,000mg/kg). Available Fe contents was 230~330mg/kg in the surface soil, and 2,200mg/kg in the subsoil. This caused bronzing of rice in a few days after transplanting. The tolerance of Fe toxicity was lower in Korean cultivars than in Liberian cultivars. The tolerant cultivar was Hangang among Korean cultivars and Nizersail and Suakoko 8 among Liberian cultivars. Area weighted average percolation rate was 8.3mm/day and infiltration rate was 2~2.5mm/hr.

• Journal of the Korean GEO-environmental Society
• /
• v.10 no.5
• /
• pp.27-32
• /
• 2009

This study evaluates tripolyphosphate's ability to treat AMD (Acid Mine Drainage). Based on the batch test results for reaction between tripolyphosphate and AMD obtained from Munkyung coal mine, $4.7{\times}10^{-3}$ mole is the optimum dosage of tripolyphosphate for AMD treatment. $Ca^{2+}$ concentration is decreased from $16.4mg/{\ell}$ to $5.6mg/{\ell}$, in other words, the removal rate of $Ca^{2+}$ is 65.9%. $Fe^{3+}$ concentration is decreased from $3.7mg/{\ell}$ to $0.02mg/{\ell}$, that is, the removal rate of $Fe^{3+}$ is 99.5%. $SO{_4}^{2-}$ concentration ranges from $526.8mg/{\ell}$ to $566.5mg/{\ell}$, which shows no obvious decrease. After dosing up tripolyphosphate, $Na^+$ concentration in AMD ranges from $549.8mg/{\ell}$ to $599.3mg/{\ell}$ and orthophosphate concentration in AMD ranges from $6.82mg/{\ell}$ to $7.60mg/{\ell}$. It was found that the precipitate in the order of amount is Apatite${\gg}{\beta}$-tricalcium phosphate > $Fe(OH)_3$ from SEM, XRF, XRD analyses. Consequently, the treatment by tripolyphosphate is effective in pH buffering and in the removal of $Ca^{2+}$ and $Fe^{3+}$.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.32 no.6
• /
• pp.514-523
• /
• 2006

The purpose of the present study was to evaluate the effects of several implant surface treatments to the bone formation, by placing Machined implants, 75${\mu}m$ Calcium phosphate-blasted implants and $Al_2O_3$-blasted and acid-etched implants in rabbit tibia through histomorphometric study. Two animals of each group were sacrificed at 2, 4, 8 weeks. The specimens containing the implants were dehydrated and embedded into hard methylmethacrylate plastic. Thereafter, the sections were ground to 50${\mu}m$. The specimens were stained with Villanueva bone stain for a light microscopic study. The results were as follows; 1. When the surface roughness of three different implants was measured by Surfcorder, the Ra of the Machined group, the RBM group and the SLA group was 0.16${\mu}m$, 0.44${\mu}m$, and 1.08${\mu}m$. 2. When examining the surfaces of the implants in the scanning microscope, Machined implant has the smooth surface with a few scratches, RBM implant has the rough surface with curled ridges and valleys, and SLA implant has the rough surface structures such as sharp protruding parts and micropits measuring 1-2${\mu}m$ in diameter. 3. After 2 weeks of implantation, the percentage of bone-to-implant contact of the Machined group, the RBM group and the SLA group was 26.86%, 35.40% and 45.99%. However, its differences between each group decreased during the healing periods. 4. After 2 weeks of implantation, the percentage of bone area inside the threads of the Machined group, the RBM group and the SLA group were 21.55%, 30.43% and 41.18%. However, its difference of bone area between machined group and surface treatment groups was maintained but the difference within the surface treatment groups decreased during the healing periods. In summary, the amount of bone formation in RBM and SLA group was greater than Machined group in early healing stage. These results suggest that RBM and SLA implants can reduce the healing period for osseointegration and may be suitable for early function.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.6
• /
• pp.729-733
• /
• 2006

Small yellowish brown crystals were found in some concentrated oyster extracts which prepared by heating with the drip and washed water of boiled oyster in oyster processing factories. We collected those crystals by filtering the oyster extracts and analysed X ray diffraction (XRD), scanning electron microscopy (SEM) and minerals by ICP. Those were composed of moisture (8.1%), organic materials (21.6%) and inorganic materials (70.2%). Those major inorganic materials were determined as Ca (53.8%) and P (43.8%), from the ICP and elucidated those crystal as brushite $(CaHPO_4{\cdot}2H_2O)$ by XRD and SEM. Organic materials contained crude protein (33.7%) consisting of 7 amino acids. It is presumed that brushite may be formed by the reaction of excess Ca with P in the oyster extracts during concentrating process under higher temperature.

• Journal of Nutrition and Health
• /
• v.41 no.6
• /
• pp.539-549
• /
• 2008

This study was conducted to examine food and nutrient intakes of weekday and weekend with 329 high school boys residing in Seoul using the 3-day food record. Frequency for breakfast skipping was the highest as compared with lunch and dinner skipping. Frequencies for breakfast and lunch skipping were significantly higher in weekend than weekday (p<0.05). The daily average food, vegetable food and animal food intakes were 1,327.6 g, 800.5 g, and 425.8 g, respectively. Total food and vegetable food intakes of weekday were significantly higher than weekend(p<0.05). The dietary variety score(DVS) was 20.5 in daily average, 23.3 in weekday and 15.1 in weekend, which showed significantly higher in weekday than weekend(p<0.05). The daily averages of energy, protein, fat and carbohydrate intake were 2244.9 kcal, 89 g, 72.6 g, and 311.2 g, respectively. Fat intake was significantly lower and carbohydrate, fiber, phosphate, iron, sodium, potassium, vitamin A, niacin, folate, and vitamin C intakes were significantly higher in weekday than weekend (p<0.05). The percentages of energy intake from carbohydrate, protein, and fat were 55.4%, 15.8%, 28.8% in daily average, 56.8%, 15.8%, 27.4% in weekday and 53.6%, 15.8%, 30.7% in weekend, respectively. The percentages of energy intake from carbohydrate in weekday and weekend were below 60%, and that from fat was above 27% in weekday and weekend. Carbohydrate intake was significantly higher and fat intake was significantly lower in weekday than weekend(p<0.05). Energy intakes of daily average, weekday and weekend were above 83% as compared with estimated energy requirement(EER). Intakes of dietary fiber, calcium, potassium, vitamin C, riboflavin and folate were below 75% as compared with adequate intake(AI) or recommended intake(RI). Mean adequacy ratios(MAR), an index of overall dietary quality were 0.78 in daily average, 0.80 in weekday and 0.75 in weekend. MAR of weekend showed significantly lower than weekday(p<0.05). This study revealed that the overall nutrient intake status was worse in weekend than weekday among high school boys.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.7 no.1
• /
• pp.40-49
• /
• 2004

This work carried out to define the characteristic of Cymbidium kanran habitat at Mt. Halla in Jejudo, Korea from the ecological point of view including geological and topographical features, air and soil temperature, relative humidity, fluctuations of light intensity, habitat vegetation, distribution altitude, area limit, and etc. And another goal of this study consider the conservation counterplan of the cymbidium habitat. Natural distribution areas of the cymbidium were observed more abundantly on the well drained south and east-facing slopes. Soil acidity was ranged from pH 4.1 to 5.3, and electric conductivity was ranged from 176.4 to 299.9 us/cm (average 215.3 us/cm). Base-saturation percentage of the habitat soil was below 50%, bulk density 0.42g/$cm^2$, particle density 2.05g/$cm^2$, humus content 26%, total nitrogen 0.82%, available phosphate 4.2 mg/kg, exchangeable potassium 0.63 Cmol/kg, calcium 0.44 Cmol/kg and magnesium 0.67 Cmol/kg. Annual mean air temperature was $15.4^{\circ}C$, however, air temperature was ranged $11.7{\sim}18.2^{\circ}C$ in spring, $21.2{\sim}23.8^{\circ}C$ in summer, $12.8{\sim}22.0^{\circ}C$ in fall and $5.5{\sim}7.8^{\circ}C$ in winter season. Annual mean soil temperature at depth of 10cm was $13.2^{\circ}C$ And minimum value was recorded $4.7^{\circ}C$ on January, and maximum value $22.5^{\circ}C$ on August. Relative humidity was ranged 90.8~94.7% in summer, 80.8~91.5% in fall and 77.6~84.2% in winter season. Minimum value was 56.5% on December, and maximum value was 100% on July and August. Light intensities were ranged from 400 to 1,800 lux at the greater part of Cymbidium kanran sites in Jejudo. Summer regarded as an lower light intensities was recorded to be range of 500~600 lux; however, autumn and winter were shown higher light regimes ranged from 3,500 to 3,800 lux. Therefore, one must be suprised that the cymbidium grow at the light condition of 6 lux (minimum) or 10,000 lux (maximum). Tree species keeping higher frequency rate and density were Eurya japonica, Camellia japonica, Castanopsis cuspidata, Carpinus laxiflora and Pinus densiflora. Number of trees growing in a 5${\times}$5m quardrat was 35 as an average, and proportion of evergreen versus deciduous was 5:1. Distribution altitude of the orchid habitat was ranged from 120m (low) to 840m (high) from sea level on the south facing slope of Mt. Halla, and was ranged eastern borderline of Gujwaup, Bukjejugun to western boundaries of Jungmundong, Seogwipo city. For the stable conservation of Cymbidium kanran habitat, sunlight regimes must be increased more by means of cutting trees or twigs in the site.

• Korean Journal of Organic Agriculture
• /
• v.20 no.4
• /
• pp.687-702
• /
• 2012

The objective of this study was to determine crop rotation effects on potato yield, soil chemical and microbiological properties from a short-term field experiment from 2010 to 2011 in Jeju Island, Korea. Potato cropping systems included continuous and rotation sequences of soybean (Glycine max(L.) Merr.), barley (Hordeum vulgare var. hexastichon), rapeseed (Brassica napus L.) and broccoli (Brassica oleracea var. italica). Crop rotations increased the yields of potato from 31% to 52% compared with continuous potato. Marketable yield of potato was highest under soybean plus rapeseed rotation by $20.97MT\;ha^{-1}$ and lowest under continuous cropping by $11.95MT\;ha^{-1}$. The incidence and severity of scab disease was significantly lower in tubers from crop rotation with soybean plus barley. Differences in marketable tuber yields among rotations were associated with potato scab disease. Especially, incidence and severity of potato scab were strongly correlated with soil pH, exchangeable calcium, and bacteria population of the soil. Crop rotations significantly increased soil pH, available phosphate, exchangeable K and Ca, especially in crop rotations with soybean plus barley or rapeseed. Soil microbial biomass C of crop rotations with soybean plus barley or rapeseed, was also significantly higher compared with monoculture. In conclusion, crop rotation may decrease the incidence of soil-born pathogen by increasing soil chemical properties and soil microbial biomass. Overall, potato crop productivity was generally maintained in rotations that contained soybean plus barley or rapeseed but declined under continuous cropping system.

• Korean Journal of Environmental Agriculture
• /
• v.39 no.1
• /
• pp.50-57
• /
• 2020

BACKGROUND: Biochar is used in various environmental fields, such as water quality and soil restoration, and affects soil fertility and nutrient cycling. Also, when crops are grown on biochar-applied soil, their characteristics may be affected. Biochar is used especially with commercial vegetable seedlings. METHODS AND RESULTS: The objective of this study was to determine the effects of biochar content in seeding mixes on early growth of lettuce (Lactuca sativa L.), Chinese cabbage (Brassica rapa L.), and red pepper (Capsicum annuum L.). Treatments consisted of a control (0: 10, ratio of biochar to seeding mixes (w/w)), 1: 9 (biochar 10%), 3: 7 (biochar 30%), 5: 5 (biochar 50%), and 7: 3 (biochar 70%). The biochar was made from risk husk and had a C/N ratio of 104. As the mixing ratio of biochar increased, pH increased whereas EC and nitrogen content decreased. The highest phosphorus content was with the treatment of 30% biochar, while there were significant increases in the weight of lettuce seedlings and concentrations of T-N, P₂O₅, K₂O, MgO, and Na with the treatments of 30% and 50% biochar. Although the weight of Chinese cabbage seedlings increased with the treatment of 10% biochar, the increase was not statistically significant. Also, there was an increase in the weight of red pepper seedlings with the treatment of 30% biochar, but the increase was not statistically significant. With increases in the biochar mixing ratio, the K₂O concentration of red pepper seedlings increased, but the concentrations of P₂O₅, CaO, MgO, and Na decreased. It was believed that this was because of absorption inhibition by calcium-phosphate formation in the seeding mixes owing to increased pH. CONCLUSION: In conclusion, adding biochar to seeding mixes is considered to be an important mean for growing healthy vegetable seedlings. More field experiments are needed to verify the effect of biochar on vegetable crop growth over the entire growing season.