• Title/Summary/Keyword: Capillary

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Analysis of the Effect of Superplasticizer combined CASB on Ultra High Strength Mortar and Concrete Using Mineral Admixture (광물질 혼화재 사용 초고강도 모르타르 및 콘크리트에 CASB 화합 고성능감수제의 효과분석)

  • Han, Cheon-Goo;Yoo, Seung-Yeup
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.6 no.1
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    • pp.72-79
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    • 2011
  • This study is performed to analyze the effects of CASB by applying the superplasticizer combined CASB on the ultra high strength mortar and concrete that uses different mineral admixture depending on whether the silica fume was used and the results are summarized below. From the characteristics of Fresh mortar and concrete, the fluidity was lower in B2-CASB than B2-PC from the mixing of CASB and based on the viscosity of the mortar and concrete in the binary proportion but in the ternary proportion, B3-CASB showed a larger fluidity than B3-PC because of a reduction in the restriction level due to the effects of an improvement of particle size distribution. The compression strength was higher in ternary proportion than in binary proportion and higher in CASB than in PC from the characteristics of hardening mortar and concrete and this is analyzed as a result of increased minuteness from the calcium silicate hydrates produced from the pozzolan reaction of a mineral admixture, SF, and also the charging effects of capillary pore of CASB. Overall, when using the nanomaterial, CASB in combination with a superplasticizer, the fluidity and the strength aspects of the ternary proportion of ultra high strength mortar and concrete with silica fume may be improved to a higher quality.

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A study of gingival blood flow using laser Doppler flowmetry (Laser Doppler Flowmetry를 이용한 치은혈류량에 관한 연구)

  • Kim, Hyung Soo;Lee, Zang-Hee;Song, Hyung-Geun;Kim, Byung-Ock;Han, Kyung-Yoon
    • Journal of Periodontal and Implant Science
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    • v.28 no.2
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    • pp.309-320
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    • 1998
  • The periodontal health has been evaluated clinically by various epidemiological indices, and in researches by measurement of gingival crevicular fluid. Laser Doppler flowmetry is a reliable and objective method that allows immediate measurement of erythrocyte flux in approximately one cubic mm of the capillary bed without disturbing the tissues. The purpose of the present study was to determine whether human gingival blood flow was different according to measuring area, measuring time, and sex or not. Forty volunteers with good general and periodontal health, aged early twenties and unmarried, were selected. Laser Doppler flowmetry($floLAB^{(R)}$, Moor Instruments Ltd., England) was applied to measure the gingival blood flow of marginal gingiva, interdental papilla, attached gingiva and alveolar mucosa. The blood flow of interdental papilla was measured at 9-10 AM, 1-2 PM, and 5-6 PM. The difference of blood flow according to measuring area and measuring time was statistically analyzed by one way AOVA and Dunkan test, and the difference of blood flow between men and women was statistically analyzed by t-test. (1) Mean blood flow was significantly higher in alveolar mucosa than in the gingiva(p<0.05), and there was no significant difference in blood flow between marginal gingiva and interdental papilla(p>0.1). (2) Mean blood flow was significantly higher at 5-6 PM than at 9-10 AM and 1-2 PM(p<0.05). But there was no significant difference in gingival blood flow between 9-10 AM and 1-2 PM(p>0.1). (3) There was no significant difference in gingival blood flow between men and women(p>0.1). The above results suggest that the measurment of gingival blood flow using laser Doppler flowmetry may be clinically applicable to early determination of gingival inflammation and evaluation of healing status, but further studies are necessary to standardize and simplify the measuring procedure.

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Effect of Crumb Rubber on the Wear Tolerance of Korean Lawngrass (폐타이어 칩이 한국들잔디의 내답압성에 미치는 영향)

  • Lee, Chung-Hwan;Kim, Ki-Sun
    • Asian Journal of Turfgrass Science
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    • v.17 no.1
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    • pp.19-33
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    • 2003
  • The objective of this study was to evaluate the effects of crumb rubber recycled from used tires as a soil incorporation and topdressing materials on a trafficked Korean lawngrass‘Zenith’(Zoysia japonica). In Exp 1, incorporation treatments included three particle sizes (PS: coarse =4∼6.35 mm, medium =2∼4 mm, and One : less than 2 mm in diameter) and two incorporation rate (IR: 10 and 20%). Wear treatments were applied 30 passes per day by compactor weights being 60 kg with soccer shoes. Topdressing treatments included three PS and two topdressing depth (TD: 5 and 10 mm). Wear treatments were the same as described in Exp 1. In Exp 1, the treatment with medium PS+IR 20 resulted in the tendency to have high total clipping yield. There was no significant difference in clipping yield, turfgrass visual color, coverage, and root length among the treatments. Compared to control, tissue Zn levels increased about 6.5-fold by the treatments. The treatment with fine PS +IR 20 caused a less peak deceleration than coarse PS +IR 10. Total porosity, air-filled porosity, and capillary porosity increased with fine PS +IR 20. In Exp 2, compared to controls, however, there was a difference in turfgrass visual color after the termination of traffic treatment. There was no difference in root length. The treatment with fine PS + TD 10 resulted in the highest total clipping yield. As a result of soil physical analysis, soil penetration resistance was reduced by the treatments. The treatment with coarse PS resulted in a less peak deceleration than fine PS. In conclusion, turfgrass growth was increased by crumb rubber incorporation which enhanced soil physical properties. The crumb rubber topdressing was able to cushion the crown tissue area while still providing a smooth and uniform surface, improve overall turfgrass quality, and reduce compaction.

A Study on the Mechanical and Rheological Properties of the Recycled Polyethylene Composites with Ground Waste Tire Powder (재생 폴리에틸렌/폐타이어 분말 복합체의 기계적 특성 및 유변학적 특성에 관한 연구)

  • Kye, H.;Shin, K.;Bang, D.
    • Elastomers and Composites
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    • v.41 no.2
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    • pp.97-107
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    • 2006
  • The recycled polyethylene composites with various ratio of ground waste tire powder were manufactured by using a fully intermeshing co-rotating twin screw extruder for the reuse of waste tire scrap. In this investigation, the ground waste tire powders (GWTP) were blended with virgin HDPE and recycled polyethylene in the weight ratio of 0 to 50 wt.%. Mechanical properties such as tensile strength, elongation at break and impact strength were measured by using ASTM standard. The experimental results for the various composite showed that the tensile strength of composites decreased with increasing GWTP ratio, while elongation at break increased with the amounts of GWTP. On the other hand, the impact strength for the three kinds of composites showed maximum at the 30 wt.% of GWTP and then decreased. Morphology of the fracture surface tends to be rough with increasing waste tire powder content. Rheological properties were investigated by measuring the shear viscosity against shear rates and softening temperatures. They showed that melt viscosity of rubber composites in this study subsequently increased with increasing GWTP content as a result of increase of flow resistance against external stress and followed a Power-law behavior.

POST-EXTUBATION ACUTE RESPIRATORY DISTRESS SYNDROME OCCURRED IN THE ORTHOGNATHIC SURGERY PATIENT : A CASE REPORT (악교정 수술 환자에서 발관 후 발생된 급성 호흡곤란 증후군 : 증례보고)

  • Park, Ji-Young;Lee, Jung-A;Yun, Sung-Hun;Park, Min-Kyou;Kim, Chang-Hyun;Park, Je-Uk
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.29 no.1
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    • pp.79-84
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    • 2007
  • Acute respiratory distress syndrome(ARDS) is severe acute hypoxic respiratory failure state with dynamic impairment in oxygen and carbon dioxide transfer with the need for high levels of supplementary oxygen and a high minute ventilation. This syndrome is caused by pulmonary edema due to increased permeability of the alveolar capillary barrier by various factors. ARDS is an uncommon, but a potentially life-threatening complication. Therefore, immediate diagnosis and appropriate therapy must be performed. The present case is post-extubation ARDS immediately occurred in an orthognathic surgery patient who are healthy 19-year-old man. He rapidly recovered from ARDS without complication by early diagnosis and proper treatment. This case report was aimed to describe the process of the development, possible causes and the management of ARDS occurred in an orthognathic surgery patient

Quantification and Varietal Variation of Rutin in Mulberry Fruits (뽕나무 계통별 오디함유 rutin 분석 및 품종변이)

  • Kim Hyun-bok;Kim Sun-lim
    • Journal of Sericultural and Entomological Science
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    • v.46 no.1
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    • pp.1-5
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    • 2004
  • Rutin has many beneficial effects on human health. It was established that rutin antagonizes the increase of capillary fragility associated with hemorrhagic disease, reduces high blood pressure, decreases the permeability of the vessels, and has an antiedema effect, reduces the risk of arteriosclerosis, and shows antioxidant activity. Rutin analysis with mulberry fruits was carried out by high-performance liquid chromatography (HPLC) to reveal the possibility of source of functional food. As a result, mean content of fifty accessions was 0.14±0.050% DW. Among the tested fifty accessions, 'Sabangso' was showed the highest rutin in 0.29%DW, whereas 'Simseol' was the lowest content in 0.05% DW. Also, we researched the change of rutin content according to harvested date. The rutin contents of earlier harvested groups were higher than later harvested groups. Simultaneously, fruity characteristics as well as rutin content were researched and analyzed to select the functional mulberry varieties for the production of fruit. From the six accessions which were contained high rutin content, we selected three suitable varieties such as 'Ficus', 'Kangsun', and 'Palcheongsipyung'.

A case of Pulmonary Veno-occlusive Disease (폐정맥 패쇄에 의한 폐고혈압증 1예)

  • Cho, Jae-Youn;Lee, Sang-Youb;Lee, Sang-Hwa;Park, Sang-Myeon;Suh, Jeong-Kyung;Shim, Jae-Jeong;In, Kwang-Ho;Kang, Kyung-Ho;Yoo, Se-Hwa;Kim, Kwang-Taek
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.274-279
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    • 1996
  • Pulmonary veno-occlusive disease is a rare cause of pulmonary hypertension in which the primary abnormality is obliterative obstruction of pulmonary veins, especially venules. Clinicaly, we should suspect this disease in the case of congestive cardiac failure with pulmonary hypertension, chronic interstitial pulmonary edema, and normal or elevated wedge pressure on cardiac catheterization. We experience a case of pulmonary hypertension due to pulmonary veno-occlusive disease. A 55-years -old woman developed progressive dry cough and dyspnea for 3 months. Physical examination showed normal heart sounds, diffuse crackles in the whole lung fields. The liver was not palpable and pitting edema was absent. The diagnosis was made by chest HRCT, 2-D echocardiography, normal pulmonary capillary wedge pressure on cardiac catheterization, and confirmed by thoracoscopic lung biopsy. This patient was treated with vasodilator(calcium antagonist) and with mild symptomatic improvement. We reported a case of pulmonary veno-occlusive disease with review of literatures.

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Comparative Sampling Procedures for the Volatile Flavor Components of Codonopsis lanceolata (전처리 방법에 따른 더덕(Codonopsis lanceolata)의 휘발성 향기성분 비교 분석)

  • Kim, Jung-Han;Kim, Kyoung-Rae;Kim, Jae-Jung;Oh, Chang-Hwan
    • Korean Journal of Food Science and Technology
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    • v.24 no.2
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    • pp.171-176
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    • 1992
  • Volatile flavor components of Codonopsis lanceolata were extracted by gas co-distillation (GCD), solvent extraction/fractionation (SEF), and headspace sampling (HSS) methods. The extracts were analyzed by dual-capillary gas chromatography-retention index (GC-RI) and gas chromatography-mass spectrometry(GC-MS). The two extracts prepared by SEF and HSS gave more similar fragrance to the Codonopsis lanceolata than the GCD extract. The GC profiles of the SEF and HSS extracts were similar to each other except for differences in peak areas. The extract prepared by SEF gave a sweet note while the extract prepared by HSS gave a green note. The GCD extract began to give a burnt note of herb medicine with prolonged distillation. Rapid extraction of flavor components from Codonopsis lanceolata was possible in several short steps by SEF and HSS methods compared to GCD. GC-MS and GC-RI were used for peak identification. GC-RI was more effective for identification of isomers, and polar FFAP column was more suitable for identification of polar compounds. From Codonopsis lanceolata we identified 35 volatile flavor constituents, 24 of which have not been previously reported by simultaneous distillation extraction method $^{(5)}$. trans-2-Hexanal, cis-3-hexen-1-ol, trans-2-hexen-1-ol, and hexanol were considered key components of the green note and 1-octen-3-ol, the component of the fresh note. Esters, including amyl propionate, seem to be responsible for the sweet note particular to Codonopsis lanceolata.

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Flux Decline Behavior in Cross-flow Microfiltration of Inorganic Colloidal Suspensions (무기 콜로이드 현탁액의 십자류 정밀여과에 의한 투과유속의 감소거동)

  • Nam Suk-Tae;Han Myeong-Jin
    • Membrane Journal
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    • v.15 no.4
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    • pp.338-348
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    • 2005
  • The permeate flux decline on microfiltration capillary membrane operation was investigated with inorganic colloidal solutions. The permeate flux of the alumina solution is two times higher in average than that of the bentonite solution. The flux decline with increase in operation time was less in the alumina solution than in the bentonite solution. The rate of initial flux decline until 10 min was higher on the bentonite solution over the alumina solution. The decline in permeate flux was due to both the cake formation and the pore blocking. The latter effect was higher in the operation of the bentonite solution. In comparing the ratio of each fouling component to the total fouling fur the $1.0\;kg_f/cm^2$ TMP condition, complete blocking was $9.35\%$, standard blocking was about $6.82\%$ and cake filtration was $83.83\%$, respectively. With the increase in cross flow velocity, the permeate flux increased by $6.0\%$ for the alumina solution and by 14.0 for the bentonite solution. With the increase in average pore size fromm $0.24\;{\mu}m\;to\;0.34\;{\mu}m$, the permeate flux increases 1.61 times for the alumina solution and 1.76 times far the bentonite solution.

Angiogenic Effect of Cardiac Ankyrin Repeat Protein Overexpression in Vascular Endo-thelial Cell (Cardiac Ankyrin Repeat Protein의 과량발현이 혈관내피세포에서 갖는 혈관신생 촉진 효과)

  • Kong, Hoon-Young;Byun, Jong-Hoe
    • Korean Journal of Microbiology
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    • v.44 no.4
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    • pp.282-288
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    • 2008
  • Tissue ischemia resulting from the constriction or obstruction of blood vessels leads to an illness that may affect many organs including the heart, brain, and legs. In recent years, considerable progress has been made in the field of therapeutic angiogenesis and the new approaches are expected to cure those "no-option patients" who are unsuited to conventional therapies. Although single angiogenic growth factor may be successful in inducing angiogenesis, combination of multiple growth factors is increasingly sought these days to augment the therapeutic responses. This trend is proper in light of the fact that blood vessel formation is a complex and multi-step process that requires the actions of many different factors. To meet the growing need for functionally significant blood flow recovery in the ischemic tissues, a novel strategy that can provide concerted actions of multiple factors is required. One way to achieve such a goal is to use a transcription factor that can orchestrate the expression of multiple target genes in the ischemic region and thus induce significant level of angiogenesis. Here, a putative transcription factor, cardiac ankyrin repeat protein (CARP), was evaluated in adenoviral vector context for angiogenic activity in human umbilical vein endothelial cells. The results indicated significant increase in proliferation, capillary-like structure formation, and induction of vascular endothelial growth factor, a typical angiogenic gene. Taken together, these results suggest that CARP represents itself as a novel target for therapeutic angiogenesis and warrants further investigation.