• Title/Summary/Keyword: Stabilization materials

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Preliminary Results of Fractionated Stereotactic Radiotherapy for Benign Brain Tumors (양성 뇌종양에 대한 분할 정위 방사선치료의 예비 결과)

  • Choi, Byung-Ock;Kang, Ki-Mun
    • Radiation Oncology Journal
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    • v.21 no.1
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    • pp.10-18
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    • 2003
  • Purpose : To evaluate the role of fractlonated sterotactic radiotherapy (FSRT) in the management of benign brain tumors, we reviewed the clinical, and radiographic responses of patients treated. Methods and Materials : Between March 1995 and March 2002, 36 patients with benign brain tumors were treated by FSRT. The pathological diagnoses consisted of pituitary adenomas (12 patients), cranio-pharyngiomas (5 patients), meningiomas (10 patients), and acoustic neurinomas (9 patients). Radiotherapy doses of 25 to 35 Gy (3~6 Gy/fraction, 5~10 fractions) were prescribed to the 85~90% isodose line, depending upon the location, size and volume of the tumors. The median clinical and radiographical follow up periods were 31 (range, 2~74) and 21 (range, 4~56) months, respectively. Results : In the 35 patients that could be evaluated for their clinical response, 13 (37.1%) were considered improved, 16 (45.7%) stable and 6 (17.2%) worse. Of the 33 patients who had radiographic studies, tumor shrinkage was noted in 17 (51.5%), tumor stabilization in 13 (39.4%), and tumor progression in 3 (9.1%). Of the 17 tumor shrinkage patients, 7 (21.2%) showed a complete response. Acute radiation-induced complications occurred iin 11 (30.6%) patients. Conclusions : FSRT is considered a safe and effective treatment method for begin brain tumors, but large numbers of patients, with relatively long follow-up periods are needed to assess the exact role or effect of FSRT.

The Effect of $\beta$-Tricalcium Phosphate and Deproteinized Bovine Bone on Bone Formation in the Defects of Rat Calvaria (흰쥐 두개골 결손부에서 베타-트리칼슘 인산염과 탈단백우골의 골형성 효과)

  • Jung, Seung-Gon;Park, Hong-Ju;Ryu, Sun-Youl
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.32 no.4
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    • pp.313-323
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    • 2010
  • Purpose: This study was conducted to evaluate the effect of beta-tricalcium phosphate (Cerasorb$^{(R)}$, Germany) and deproteinized bovine bone (Bio-Oss$^{(R)}$, Switzerland) grafted to the defect of rat calvaria artificially created and the effect of use of absorbable membrane (BioMesh$^{(R)}$, Korea) on new bone formation. Materials and Methods: Transosseous circular calvarial defects with diameters of 5 mm were prepared in the both parietal bone of 30 rats. In the control group I, no specific treatment was done on the defects. In the control group II, the defects were covered with absorbable membrane. In the experimental group I, deproteinized bovine bone was grafted without absorbable membrane; in the experimental group II, deproteinized bovine bone was grafted with absorbable membrane; in the experimental group III, beta-tricalcium phosphate was grafted without absorbable membrane; in the experimental group IV, beta-tricalcium phosphate was grafted with absorbable membrane. The animals were sacrificed after 3 weeks and 6 weeks respectively, and histologic and histomorphometric evaluations were performed. Results: Compare to the control groups, the experimental groups showed more newly formed bone. Between the experimental groups, beta-tricalcium phosphate showed more resorption than deproteinized bovine bone. Stabilization of grafted material and interception of the soft tissue invasion was observed in the specimen treated with membrane. There was no statistical difference between the experimental group I, III and experimental group II, IV classified by graft material, but statistically significant increase in the amount of newly formed bone was observed in the experimental group I, II and II, IV classified by the use of membrane (P<0.05). Conclusion: Both beta-tricalcium phosphate and deproteinized bovine bone showed similar osteoconductibility, but beta-tricalcium phosphate is thought to be closer to ideal synthetic graft material because it showed higher resorption rate in vivo. Increased new bone formation can be expected in bone graft with use of membrane.

Magnetic resonance imaging Usefulness after Medial Meniscus Posterior Root Tear Repair (내측 반월상 연골판 후각 기시부 파열 봉합 후 추시 자기공명영상 검사의 유용성)

  • Chon, Jegyun;Kim, Jun-Beom;Lee, Bong-Ju
    • Journal of the Korean Arthroscopy Society
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    • v.17 no.1
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    • pp.6-10
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    • 2013
  • Purpose: This study intends to verify the usefulness of magnetic resonance imaging (MRI) for estimate recovery after arthroscopic pull-out repair at root tears of medial meniscus. Materials and Methods: We performed 17 patients who examined MRI and arthroscopy among patients who had received repair of medial meniscus from November, 2007 to June, 2011. To determine restoration meniscus, we performed arthroscopy and MRI. Results: Lysholm knee scores before and after operation were average 56.4 and 79.0 and visual analogue scale (VAS) score was improved from 8 points to 3 points. From secondary look arthroscopy performed after operation, 17 cases showed stabilization after regeneration. However, In MRI, cleft sign implying root tears of medial meniscus was observed in all cases before and after operation, ghost sign was observed in 10 cases and 9 cases respectively, radial linear defect was showed 17 cases and 15 cases respectively. Conclusion: It was not useful that MRI after medial meniscus repair in non-anatomical site, to consider restoration of medial meniscus. To evaluate for recovery medial meniscus after repair more exactly, secondary arthroscopy would be required.

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A Study on Effects of Vulcanization Systems on Cross-linking and Degradation Reactions of NR/CR Blends Using Dynamic DSC and TGA (Dynamic DSC와 TGA를 이용한 NR/CR 고무블렌드의 가황시스템이 가교 및 열화반응에 미치는 영향 연구)

  • Min, Byung-kwon;Park, DongRyul;Ahn, WonSool
    • Korean Chemical Engineering Research
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    • v.47 no.2
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    • pp.169-173
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    • 2009
  • Effects of variations sulfur/accelerator ratio on cross-linking and thermal degradation behavior of NR/CR rubber compounds were studied using both dynamic DSC and non-isothermal TGA. DSC thermograms of the given samples were obtained with several different heating rates, and after cross-liked in DSC, TGA thermograms with the same samples also obtained. Kissinger analysis was applied to assess the activation energies for the cross-linking and thermal decomposition processes. Results showed that the formation and thermal decomposition reaction of the samples occurred in the overall temperature range of $120{\sim}180^{\circ}C$ and $350{\sim}450^{\circ}C$, respectively, exhibiting that data could be well-fittable by Kissinger method. Furthermore, formation activation energy by DSC was estimated as $83.0{\pm}5.0kJ/mol$, which was much smaller than that of degradation by TGA, $147.0{\pm}2.0kJ/mol$. From these results, it was considered that, although variations of sulfur/accelerator ratio in the present experiments affected little on the formation mechanism and/or thermal degradation, they could play roles as the catalysts which lower the activation energy of formation. Because of stabilization after formation reaction, however, they have no more effects on the lowering the activation energy, showing higher values when decomposition, caused by main-chain scissions.

Efficacy and Tolerability of Weekly Docetaxel, Cisplatin, and 5-Fluorouracil for Locally Advanced or Metastatic Gastric Cancer Patients with ECOG Performance Scores of 1 and 2

  • Turkeli, Mehmet;Aldemir, Mehmet Naci;Cayir, Kerim;Simsek, Melih;Bilici, Mehmet;Tekin, Salim Basol;Yildirim, Nilgun;Bilen, Nurhan;Makas, Ibrahim
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.3
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    • pp.985-989
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    • 2015
  • Background: Docetaxel, cisplatin, 5-fluorouracil (DCF) given every three weeks is an effective, but palliative regimen and significantly toxic especially in patients who have a low performance score. Here, we aimed to evaluate the efficacy and tolerability of a weekly formulation of DCF in locally advanced and metastatic gastric cancer patients. Materials and Methods: 64 gastric cancer patients (13 locally advanced and 51 metastatic) whose ECOG (Eastern Cooperative Oncology Group) performance status (PS) was 1-2 and who were treated with at least two cycles of weekly DCF protocol as first-line treatment were included retrospectively. The weekly DCF protocol included $25mg/m^2$ docetaxel, $25mg/m^2$ cisplatin, and 24 hours infusion of $750mg/m^2$ 5-fluorouracil, repeated every week. Disease and patient characteristics, prognostic factors, treatment response, grade 3-4 toxicity related to treatment, progression free survival (PFS) and overall survival (OS) were evaluated. Results: Of the patients, 41 were male and 23 were female; the median age was 63 (29-82) years. Forty-one patients were ECOG-1 and 23 were ECOG-2. Of the total, 81.2% received at least three cycles of chemotherapy. Partial response was observed in 28.1% and stabilization in 29.7%. Overall, the disease was controlled in 57.8% whereas progression was noted in 42.2%. The median time to progression was 4 months (95%CI, 2.8-5.2 months) and median overall survival was 12 months (95%CI, 9.2-14.8 months). The evaluation of patients for grade 3-4 toxicity revealed that 10.9% had anemia, 7.8% had thrombocytopenia and 10.9% had neutropenia. Non-hematologic toxicity included renal toxicity (7.8%) and thrombosis (1.6%). Conclusions: In patients with locally advanced or metastatic gastric cancer who were not candidates for DCF administered every-3-weeks, a weekly formulation of DCF demonstrated modest activity with minimal hematologic toxicity, suggesting that weekly DCF is a reasonable treatment option for such patients.

A study on the Recovery of waste fluids of the conservation treatment of waterlogged wooden artifacts (수침목재유물보존처리 폐액의 재활용에 관한 연구)

  • Yang, Seok-Jin;Kim, Jong-Hwa;Song, Ju-Yeong;Lee, Soo
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.1
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    • pp.108-115
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    • 2012
  • Archaeological waterlogged woods found under the sea, in lakes, or in swamp environments are generally weak and fragile. If waterlogged wood materials were taken out of the water and left without modification, they would collapse and lose their original dimensions completely. Conservation is performed to replace the water with chemical agents and to give dimensional stabilization and durability. EDTA and PEG are the most commonly used in the preservation of wood. pH control-precipitation method is used for recovery of EDTA from waste fluid of archeological waterlogged wood conservation treatment. The black substance is eliminated from wood as Fe-EDTA complex are formed and EDTA is separated and precipitated from Fe-EDTA complexes at pH 2.68 or less. The result of analysis of the precipitated products and the commercial EDTA by FT-IR and FE-SEM showed that precipitated product by pH adjusted was not a type of Fe-EDTA complex, but pure EDTA. Waste fluid produced in PEG treatment shows the black color and has an offensive odor by organic matter extracted from wood. Color of waste fluid is decolored with oxidation reaction by peroxy hydrate. In FT-IR and SEM-EDX of PEG after freeze-drying process, no significant change of functional groups induced from oxidation is observed, and any metal ion does not exist in the solid PEG specimen. The molecular weight of PEG is measured using GPC and viscometry. Properties of PEG before and after preservation treatment, and after oxidation with $H_2O_2$ were not changed. Consequently, the peroxidation with $H_2O_2$ is a reasonable and simple method to decolor the used PEG solution.

A Study Based on Molecular Orbital Theory of Polymerization of Oxetane High Explosives (옥세탄 고폭 화약류의 중합반응에 관한 분자 궤도론적 연구)

  • Kim, Joon-Tae
    • Applied Chemistry for Engineering
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    • v.20 no.2
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    • pp.159-164
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    • 2009
  • Monomers of oxetane high explosives were theoretically examined in terms of reactivity, reaction mechanism and process of polymerization substituted by azido $(-CH_2N_3)$, nitrato $(-CH_2ONO_2)$ and hydrazino $(-CH_2N_2H_3)$ which belong to the 5th class hazardous materials and have explosiveness under acid catalyst using MINDO/3, MNDO, and AMI methods for formal charge, heat of formation, and energy level. Nucleophilicity and base of oxetane high explosives could be explained by negative charge size of oxetane oxygen atom and reactivity of oxetane in the growth stage of polymerization under acid catalyzer could be expected to be governed by positive charge size of axial carbon atom and low LUMO energy of electrophile. It could be estimated that carbenium ion was more beneficial in the conversion process of oxetane high explosives than that of stabilization energy (13.90~31.02 kcal/mole) of oxonium ion. In addition, concentration of oxonium ion and carbenium ion in equilibrium state influenced mechanism and it was also estimated that $S_N1$ mechanism reacts faster than that of $S_N2$ in prepolymer growth stage considering quick equilibrium based on form and calculation of polymerization under acid catalyzer.

A Study on the Apparel Industry and the Clothing Culture of North Korea (북한(北韓)의 의류산업(衣類産業)과 의생활문화(衣生活文化) 연구(硏究))

  • Cho, Kyu-Hwa
    • Journal of Fashion Business
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    • v.5 no.4
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    • pp.158-175
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    • 2001
  • The purpose of this study was to understand and improve the clothing habits and the apparel industry of North Korea in preparation for the reunification of South and North Korea. For this study, literary data, reports, periodicals, interviews and internet data of the two Koreas were reviewed. North Korean clothing habits used to be monotonous and uniform but nowadays people's clothes have become somewhat brighter in color and more diverse in design than before. In particular, liberal and individual dressing habits appeared among the privileged classes. When taking part in national events, women have to wear the traditional Korean costume, Hanbok, while men wear business suits for formal wear. In general, men don't wear Hanbok. Students have to be in uniforms but blue jeans, T-shirts with English logos were popular among them reflecting their sensitivity and openness towards western cultures. The brides usually wear pink Hanboks and the bridegrooms wear black business suits for their wedding. North Koreans also wear Hanbok on national holidays like South Koreans. Clothing is the most important item in the trade of process commission between North and South Korea. Trading items are mid to low end men's clothing for the most part due to less emphasis on fashion in the North. The processing is indirect trade and composed of sample making and contracting, sending out materials and production, carrying in goods and setting accounts. To activate South-North trade, establishment of infrastructure, stabilization of shipping, reducing high costs of distribution, building direct communication system by setting up office in a neutral zone and simplifying procedures in applying for the South and North Korea Economic Cooperation Fund. On the other hand, clothing and textiles education is carried on at art colleges, light industries colleges and commercial colleges in Pyongyang. Clothing institutes which study Hanbok and Western clothes, are installed in each city and province. Graduates who majored in clothing and textiles are posted in institutes or apparel factories. Their job is designing, patternmaking and sewing for their customers. Most of them are women and in good state of economic conditions. The North Korean clothing industry has been the core national industry that has developed based on overseas demand form the mid 1980s. The standard is that of South Korea in the early 1980s. In 1999, trade of North Korean textile products with trade counterparts such as Japan and China was $1.3 million in exports and $1.27 in imports. Of this amount the export takes up 25.4% of the total exports in North Korea. However, fundamentally even in sectors that are irrelevant to politics such as the fashion clothing industry, trust between the South and North should be a prerequisite. Only through this can exchange between North and South and economic cooperation contribute towards the reunification.

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The Analysis of Effect of Biopolymer Treated Soils in Seed Spray Method in the River Embankment (제방 녹화공법에서 바이오폴리머 처리토의 효능 분석)

  • Seo, Seunghwan;Jin, Seungnam;Chang, Ilhan;Chung, Moonkyung
    • Ecology and Resilient Infrastructure
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    • v.6 no.4
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    • pp.304-313
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    • 2019
  • Biopolymer based on microbial β-glucan and xanthan gum is effective for vegetation and has a function of enhancing soil strength, which can be used as soil reinforcement and stabilization materials in river embankment. The purpose of this study is to verify the vegetation effect of the surface of levee by biopolymer with seed spraying method. Mixed soils with biopolymer were used to cover the surface of embankments. The strength is higher in biopolymer-treated soil and xanthan gum based biopolymer has advantage for quality control in field scale. In addition, the vegetation of F. arundinacea and L. perenne showed various reactions with types of biopolymers. Biopolymer has a positive effect on the vegetation of them. In contrast, root growth tended to decrease in biopolymer-treated soils. The results indicate that root growth is slow down due to increasing ability to retain water in biopolymer-treated soil. In order to apply biopolymer to river embankment, it is necessary to examine the effects of biopolymers on a wide range of plant species in river embankment.

Evaluation of the Stability of Geomembrane Liner System in Closed Waste Landfill (사용종료 폐기물 매립장의 멤브레인 차수시스템 안정성 평가)

  • Lee, Heung-Gil;Oh, Young-In
    • Journal of the Korean Geosynthetics Society
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    • v.9 no.1
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    • pp.39-46
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    • 2010
  • Recently, the effective use of closed waste landfill nearby urban areas has been demanded, because of the lack of the usable land. However, the reuse of closed landfill is needed an adequate stabilization of liner system. But most of these places are consisted of steep slope and hence it is necessary to use the geosynthetics liners in there. Liner system of waste landfills is an important facility which prevents leachate outgoing from the landfills and also groundwater infiltrating from surroundings into the landfills. During the waste disposal stage, differential settlement and tensile stress of the geosynthetic materials could occur due to impact load of trucks and dozers, waste loads and weak foundation soils. In this study, the tensile strength and tracer test were performed to evaluate the stability of geomembrane liner systems. Based on the tensile strength test result of in-situ geomembrane sample, the yield tensile strength maintain the suitable strength by specification and current law. However, according to the tracer test, the damage of geomembrane liner was detected on sanitary landfill section.

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