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Studies on a Plan for Afforestation at Tong-ri Beach Resort(II) -Analyses of Crown Amounts and Soil Properties in the Disaster-damage Prevention Forests of Pinus thunbergii PARL., the Valuation on Soil Properties for Planting and Planning for Afforestation- (통리(桶里) 해수욕장(海水浴場) 녹지대(綠地帶) 조성(造成)에 관(關)한 연구(硏究)(II) -곰솔 해안방재림(海岸防災林)의 수관량(樹冠量) 및 토양분석(土壤分析), 식재기반평가(植栽基盤評價) 및 녹지대계획(綠地帶計劃)-)

  • Cho, Hi Doo
    • Journal of Korean Society of Forest Science
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    • v.77 no.3
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    • pp.303-314
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    • 1988
  • Tong-ri beach has not enough vegetation to be enjoyed by the sea bathers and to be satisfied with preventing the disaster-damages, but mixed forest near the beach can work its funtions and the old forest of Pirus thunbergii $P_{ARL}$. near the beach do a Little. Therefore it is very urgent to plant more trees near the beach for bathers and disaster-damage prevention. This study was carried out for planning an afforestation, with reporting upon the crown amounts and soil properties of disaster-damage prevention forests of P. thunbergii $P_{ARL}$. planted on the coast sand dunes in 1970 and 1976, and with reporting upon the valuation on soil properties of the lands near the beach in order to set the afforestation site. The results are as follows : 1. In disaster-damage prevention forests, crown surface area and crown volume became increasingly greater in proportion to the height. To D.B.H., crown volume also became increasingly greater in proportion, but crown surface area was directly proportional. 2. In comparison to sail characteristics of sand dune, those of the forests were in large quantity in OM, T-N and avail. $SiO_2$, and almost in the same in avail. $P_2O_5$, but in small quantity in exchangeable canons : K, Ca, Mg and Na. 3. EC, Cl and pH were in small value in the forest soils, but CEC was in large value in those soils. 4. Above facts showed that the forests fulfill their functions for preventing disaster-damages and improve their soil properties. 5. The forests have naturally been thinned up to 34% in 17 years and 39% in 11 years, and one can easily pass through the forest(planted in 1970), because of its sufficient clear-length(2.71m) and its space to pass. 6. A plan for afforestation was oracle nut after judging several sites by the evaluation on the soil properties and considering the best relaxation and the prevention of the various disaster-damages upon which were reported in the last issue. 7. Afforestation should be kept for maintaining its appropriate density for best relaxation and disaster-damage prevention.

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Comparisons of Unicortical and Bicortical Lateral Mass Screws in the Cervical Spine : Safety vs Strength (경추부의 후관절 나사못 고정술에서 단피질삽입법과 양피질 삽입법 간의 특성에 관한 비교)

  • Park, Choon-Keun;Hwang, Jang-Hoe;Ji, Chul;Lee, Jae Un;Sung, Jae Hoon;Choi, Seung-Jin;Lee, Sang-Won;Seybold, Eric;Park, Sung-Chan;Cho, Kyung-Suok;Park, Chun-Kun;Kang, Joon-Ki
    • Journal of Korean Neurosurgical Society
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    • v.30 no.10
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    • pp.1210-1219
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    • 2001
  • Introduction : The purpose of this study was to analyze the safety, pullout strength and radiographic characteristics of unicortical and bicortical screws of cervical facet within cadaveric specimens and evaluate the influence of level of training on the positioning of these screws. Methods : Twenty-one cadavers, mean 78.9 years of age, underwent bilateral placement of 3.5mm AO lateral mass screw from C3-C6(n=168) using a slight variation of the Magerl technique. Intraoperative imaging was not used. The right side(unicortical) utilized only 14mm screws(effective length of 11mm) while on the left side to determine the length of the screw after the ventral cortex had been drilled. Three spine surgeons(attending, fellow, chief resident) with varying levels of spine training performed the procedure on seven cadavers each. All spines were harvested and lateral radiographs were taken. Individual cervical vertebrae were carefully dissected and then axial radiographs were taken. The screws were evaluated clinically and radiographically for their safety. Screws were graded clinically for their safety with respect to the spinal cord, facet joint, nerve root and vertebral artery. The grades consisted of the following categories : "satisfactory", "at risk" and "direct injury". Each screw was also graded according to its zone placement. Screw position was quantified by measuring a sagittal angle from the lateral radiograph and an axial angle from the axial radiograph. Pull-out force was determined for all screws using a material testing machine. Results : Dissection revealed that fifteen screws on the left side actually had only unicortical and not bicortical purchase as intended. The majority of screws(92.8%) were satisfactory in terms of safety. There were no injuries to the spinal cord. On the right side(unicortical), 98.9% of the screws were "satisfactory" and on the left side(bicortical) 68.1% were "satisfactory". There was a 5.8% incidence of direct arterial injury and a 17.4% incidence of direct nerve root injury with the bicortical screws. There were no "direct injuries" with the unicortical screws for the nerve root or vertebral artery. The unicortical screws had a 21.4% incidence of direct injury of the facet joint, while the bicortical screws had a 21.7% incidence. The majority of "direct injury" of bicortical screws were placed by the surgeon with the least experience. The performance of the resident surgeon was significantly different from the attending or fellow(p<0.05) in terms of safety of the nerve root and vertebral artery. The attending's performance was significantly better than the resident or fellow(p<0.05) in terms of safety of the facet joint. There was no relationship between the safety of a screw and its zone placement. The axial deviation angle measured $23.5{\pm}6.6$ degrees and $19.8{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The resident surgeon had a significantly lower angle than the attending or fellow(p<0.05). The sagittal angle measured $66.3{\pm}7.0$ degrees and $62.3{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The attending had a significantly lower sagittal angle than the fellow or resident(p<0.05). Thirty-three screws that entered the facet joint were tested for pull-out strength but excluded from the data because they were not lateral mass screws per-se and had deviated substantially from the intended final trajectory. The mean pull-out force for all screws was $542.9{\pm}296.6N$. There was no statistically significant difference between the pull-out force for unicortical($519.9{\pm}286.9N$) and bicortical($565.2{\pm}306N$) screws. There was no significant difference in pull-out strengths with respect to zone placement. Conclusion : It is our belief that the risk associated with bicortical purchase mandates formal spine training if it is to be done safely and accurately. Unicortical screws are safer regardless of level of training. It is apparent that 14mm lateral mass screws placed in a supero-lateral trajectory in the adult cervical spine provide an equivalent strength with a much lower risk of injury than the longer bicortical screws placed in a similar orientation.

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Effects of Pranlukast on Ovalbumin Induced Early-Phase Bronchoconstriction in Guinea Pigs (기니픽에서 Ovalbumin으로 유발된 즉시형 기관지 수축반응에 대한 Pranlukast의 효과)

  • Lee, Sin-Hyung;Shim, Jae-Jeong;Kim, Kyung-Kyu;Jeong, Hye-Cheol;Kwon, Young-Hwan;Kim, Je-Hyeong;Lee, Sung-Yong;Lee, So-Ra;Lee, Sang-Youb;Cho, Jae-Youn;In, Kwang-Ho;Yoo, Se-Hwa;Kang, Kyung-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.5
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    • pp.697-708
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    • 1999
  • Background : Leukotriene (LT) $C_4$, $D_4$, and $E_4$, the main components of slow-reacting substance of anaphylaxis (SRS-A), have been suggested to play an important role in bronchial asthma such as antigen-induced bronchoconstriction, airway hyperreactivity, and pulmonary eosinophil accumulation. The purpose of this study was to evaluate the effects of treatment with the cysteinyl-LTs (cys-LTs) antagonist, pranlukast on allergen-induced guinea pig asthma model. Methods : Guinea pigs of treatment and placebo groups were sensitized by subcutaneous injection of ovalbumin(OVA) and challenged by inhalation of aerosolized OVA (1% weight/volume OVA). Normal control group did not sensitize with OVA. Oral ingestion of pranlukast and normal saline to the treatment and placebo groups was performed. In the treatment and placebo groups, airway resistance was measured before and after oral ingestion. Serum $LTC_4$ and eosinophilic infiltration of the bronchiolar and peribronchiolar tissues were measured after ingestion in the treatment and placebo groups. Results : Allergen-induced airway constriction developed in 20 (8 in treatment group, 12 in placebo group) among 35 guinea pigs. Airway resistance was significantly decreased at 3 and 6 minutes after OVA challenge in the pranlukast treatment group. In the placebo group, there was no difference of airway resistance between before and after saline ingestion. Serum $LTC_4$ levels showed 348.4 pg/ml in the treatment group, 373.9 pg/ml in the placebo group, and 364.4 pg/ml in the control group. There were no statistically significant difference between treatment and placebo group (p=0.232), and treatment and control group (p=0.501). Eosinophilic infiltrations in the peribronchiolar region per one-microscopic field ($\times$400 high power fields) demonstrated 7.06 in the treatment group, 19.2 in the placebo group, and 4.50 in the control group. There was significant decrement of eosinophilic infiltration in the treatment group which was compared with placebo group (p=0.001). Conclusion : These results demonstrate that pranlukast, a cys-LTs receptor antagonist, can attenuate allergen induced early-phase bronchoconstriction and eosinophilic infiltration in the bronchiolar tissues.

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Comparison of Nutrient Intakes of Korean Elderly People Living in Rural Area Between 24-hour Recall and Food Frequency Method (24시간회상법과 식품섭취빈도조사법을 이용한 농촌지역 노인의 영양소 섭취수준 비교)

  • Cho, Young-Eun;Lee, Soo-Lim;Cho, Eun-Hyun;Lomeda, Ria-Ann L;Kwak, Eun-Hee;Kim, Yang-Ha;Kwun, In-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.6
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    • pp.698-707
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    • 2006
  • Precise and correct assessment of nutrient intake using appropriate dietary intake method is necessary to improve the nutritional status of the target people group. It is more likely so in elderly people since their dietary habits and inadequate nutrient intakes are of special concern even worse in rural areas. Two popular methods of gathering dietary intake are 24-hour recall and food frequency method (or food frequency questionnaire). In the present study, we conducted both 24-hour recall and food frequency method on 120 rural elderly people $(aged\;65{\sim}74\;years)$, 62 male and 58 female. The dietary intakes were analyzed and the correlation of the dietary intake between 24-hour recall and food frequency method to determine the reliability between two methods. Also each nutrient intake was compared to recommended dietary allowance (RDA) or nutrient reference value (NRV) as appropriate. Even correlation did not show significance between the two methods except for dietary fiber intake (0.65 at p<0.01) and energy-yielding nutrients which mostly showed similar results with nutrient intake level. These support the possible reliability between 24-hours record and food frequency method that is also shown on the cases of most mineral and vitamin intakes. Thus, the food frequency method used in this study for the assessment of nutrient intakes of the elderly people would be reliable for the assessment of the nutrient intake along with the 24-hour recall. Also, the present study results suggested that rural female elderly people would be under optimal nutriture status due to the lower food intake measured by 24-hour recall. The optimal food frequency method would be considered to be developed for the precise nutrient assessment.