• 제목/요약/키워드: Unusual-behavior

검색결과 133건 처리시간 0.032초

Solid Lipid Nanoparticles as Drug Delivery System for Water-Insoluble Drugs

  • Li, Rihua;Lim, Soo-Jeong;Choi, Han-Gon;Lee, Mi-Kyung
    • Journal of Pharmaceutical Investigation
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    • 제40권spc호
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    • pp.63-73
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    • 2010
  • Solid lipid nanoparticles (SLNs) have emerged to combine the advantages of polymeric nanoparticles and lipid emulsions in early 1990s. SLNs can present several desirable properties derived from the solid state core. When formulating SLNs, there should be careful considerations about the physical state of the inner solid lipid core and its polymorphism and supercooling behavior. In this review, SLNs were compared to lipid emulsion and emulsion of supercooled melt to understand the unusual behaviors compared to lipid emulsions and to have insights into stability and release mechanism. SLNs have been regarded as biocompatible system because lipids are usually well-tolerable ingredients than polymers. Several studies showed good tolerability of SLNs in terms of cytotoxicity and hemolysis. Similar to various other nanoparticulate drug delivery systems, SLNs can also change biodistribution of the incorporated drugs in a way to enhance therapeutic effect. Most of all, large scale production of SLNs was extablished wihtout using organic solvents. Although there is no SLN product in the market till date, several advantagious properties of SLNs and the progress we have seen so far would make commercial product of SLNs possible before long and encourage research community to apply SLN-based formulations for water-insoluble drugs.

Applicability of Existing Fracture Initiation Models to Modern Line Pipe Steels

  • Shim, Do Jun
    • 한국압력기기공학회 논문집
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    • 제12권2호
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    • pp.1-24
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    • 2016
  • The original fracture criteria developed by Maxey/Kiefner for axial through-wall and surface-cracked pipes have worked well for many industries for a large variety of relatively low strength and toughness materials. However, newer line pipe steels have some unusual characteristics that differ from these older materials. One example is a test data that has demonstrated that X80 line-pipe with an axial through-wall-crack can fail at pressures about 30 percent lower than predicted with commonly used analysis methods for older steels. Thus, it is essential to review the currently available models and investigate the applicability of these models to newer high-strength line pipe materials. In this paper, the available models for predicting the failure behavior of axial-cracked pipes (through-wall-cracked and external surface-cracked pipes) were reviewed. Furthermore, the applicability of these models to high-strength steel pipes was investigated by analyzing limited full-scale pipe fracture initiation test results. Based on the analyzed results, the shortcomings of the available models were identified. For both through-wall and surface cracks, the major shortcomings were related to the characterization of the material toughness, which generally leads to non-conservative predictions in the J-T analyses. The findings in this paper may be limited to the test data that were consider for this study. The requisite characteristics of a potential model were also identified in the present paper.

Seismic design strategy of cable stayed bridges subjected to strong ground motions

  • Xu, Yan;Duan, Xinzhi;Li, Jianzhong
    • Structural Engineering and Mechanics
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    • 제51권6호
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    • pp.909-922
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    • 2014
  • In this paper, we present an alternative seismic design strategy for cable stayed bridges with concrete pylons when subjected to strong ground motions. The comparison of conventional seismic design using supplemental dampers (strategy A) and the new strategy using nonlinear seismic design of pylon columns (strategy B) is exemplified by one typical medium span cable stayed bridge subjected to strong ground motions from 1999 Taiwan Chi-Chi earthquake and 2008 China Wenchuan earthquake. We first conducted the optimization of damper parameters according to strategy A in response to the distinct features that strong ground motions contain. And then we adopted strategy B to carry out seismic analysis by introducing the elastic-plastic elements that allowing plasticity development in the pylon columns. The numerical results show that via strategy A, the earthquake induced structural responses can be kept in the desired range provided with the proper damping parameters, however, the extra cost of unusual dampers will be inevitable. For strategy B, the pylon columns may not remain elastic and certain plasticity developed, but the seismic responses of the foundation will be greatly decreased, meanwhile, the displacement at the top of pylon seems to be not affected much by the yielding of pylon columns, which indicates the pylon nonlinear design can be an alternative design strategy when strong ground motions have to be considered for the bridge.

폐 전이를 일으킨 재발성 거대세포종 - 증례 보고 - (Metastasising Recurrent Giant Cell Tumor - A Case Report -)

  • 김태승;박준식
    • 대한골관절종양학회지
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    • 제7권2호
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    • pp.73-79
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    • 2001
  • 슬관절을 중심으로 대퇴골 원위부, 경골 근위부에 호발하는 거대세포종은 양성 종양임에도 불구하고 그 생물학적 양상이 때로는 매우 공격적이어서 심한 골파괴를 초래하여 치료적 측면에서 관절의 연골면을 보존하는 문제에 봉착하게 된다. 또한, 소파술과 단순한 골이식술을 시행한 경우 재발 가능성이 매우 높으며, 간혹 폐전이에 대한 보고도 있는바 양성으로서의 거대세포종이 항상 관심의 대상이 되고 있다. 본 교실에서는 25세 남자 환자에서 대퇴골 원위부에 발생한 양성의 거대세포종을 골소파술과 methylmethacrylate 충전을 시행하였으나, 수술 후 2년 후에 재발과 더불어 폐 전이를 일으킨 예에 대해서 문헌 고찰과 함께 증례 보고하는 바이다.

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초현실주의 예술의 조형성과 Schiaparelli 의상디자인 (Surrealist Art and Elsa Schiaparelli's Fashion Design)

  • 장동림
    • 대한가정학회지
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    • 제28권2호
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    • pp.1-14
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    • 1990
  • The purpose of this paper was to examine the relationship between Surrealism and Schiaparelli's fashion design in the 1930s. Surrealism, derived from Dadaism, was based on Freud's analysis of dream imagery and human sexual behavior. Its style was characterized by the partial figure and the dislocation of body part, and the placement of the figure and its part in unanticipated settings. The objective of Surrealism was to exploit the unconsciousness and the interpretation of the body became an abiding. Surrealists were interested in the nature of clothing and in the specific characteristic of fashion, so, they moved into the world of fashion; fashion advertising window display and fashion photograph. The fantasy of Surrealism stimulated Schiaparelli to use wit and shock tactics, bold and unusual combination of colors, striking embroideries with crazy themes like circus and astrology. The character of her clothes was boldness and chic. She created humorous trompe-l'oel sweater, leg of mutton sleeve, tweed evening suit, shocking pink, peculiar accessories such as hats and buttons. She collaborated with many artists like Dali, Cocteau and Berard, and drew on all the latest artistic trends into the fashion arena from Cubism and African Art to Surrealism. Her Surrelist dress provided a play of illusions and affected today;s avant-grade style.

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Damage detection on output-only monitoring of dynamic curvature in composite decks

  • Domaneschi, M.;Sigurdardottir, D.;Glisic, B.
    • Structural Monitoring and Maintenance
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    • 제4권1호
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    • pp.1-15
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    • 2017
  • Installation of sensors networks for continuous in-service monitoring of structures and their efficiency conditions is a current research trend of paramount interest. On-line monitoring systems could be strategically useful for road infrastructures, which are expected to perform efficiently and be self-diagnostic, also in emergency scenarios. This work researches damage detection in composite concrete-steel structures that are typical for highway overpasses and bridges. The techniques herein proposed assume that typical damage in the deck occurs in form of delamination and cracking, and that it affects the peak power spectral density of dynamic curvature. The investigation is performed by combining results of measurements collected by long-gauge fiber optic strain sensors installed on monitored structure and a statistic approach. A finite element model has been also prepared and validated for deepening peculiar aspects of the investigation and the availability of the method. The proposed method for real time applications is able to detect a documented unusual behavior (e.g., damage or deterioration) through long-gauge fiber optic strain sensors measurements and a probabilistic study of the dynamic curvature power spectral density.

Chemical Modification of Carbon Nanotubes and Preparation of Polystyrene/Carbon Nanotubes Composites

  • Ham, Hyeong-Taek;Koo, Chong-Min;Kim, Sang-Ouk;Park, Yeong-Suk;Chung, In-Jae
    • Macromolecular Research
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    • 제12권4호
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    • pp.384-390
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    • 2004
  • Single-walled carbon nanotubes (SWNTs) have been chemically modified through the formation of carboxylic acid functionalities or by grafting octadecylamine and polystyrene onto them. We purified SWNTs with nitric acid to remove some remaining catalysts and amorphous carbon materials. After purification, we broke the carbon nanotubes and shortened their lengths by using a 3:1 mixture of concentrated sulfuric acid and nitric acid. During these purification and cutting processes, carboxylic acid units formed at the open ends of the SWNTs. Octa-decylamine and amino-terminated polystyrene were grafted onto the cut SWNTs by condensation reactions between the amine and carboxylic acid units. The cut SWNTs did not disperse in organic solvents, but the octadecylamine-grafted and polystyrene-grafted SWNTs dispersed well in dichloromethane and aromatic solvents (e.g., benzene, toluene). Composites were prepared by mixing polystyrene with the octadecylamine-grafted or polystyrene-grafted SWNTs. Each composite had a higher dynamic storage modulus than that of a pristine polystyrene. The composites exhibited enhanced storage moduli, complex viscosities, and unusual non-terminal behavior when compared with a monodisperse polystyrene matrix because of the good dispersion of carbon nanotubes in the polystyrene matrix.

하천제방축조재료로서 시멘트혼합토의 특성 (Characterization of Cemented Sand for Building of Levee)

  • 정우섭;김영수
    • 한국방재학회 논문집
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    • 제6권4호통권23호
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    • pp.29-36
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    • 2006
  • 최근 이상기후 및 집중호우로 인해 낙동강유역의 많은 지역이 재산 및 인명손실을 크게 입고 있으며 제방축조 재료의 획득 및 운송비등의 증가로 인해 재해방지차원의 제방축조에 여러 가지 어려움을 겪고 있는 실정이다. 본 연구에서는 낙동강 하상의 모래를 이용하여 소량의 시멘트를 혼합한 시멘트혼합토에 대해 삼축압축실험을 통해 시멘트혼합율에 따른 특성을 규명하고자 한다. 이를 위하여 낙동강유역 하상 모래와 시멘트의 혼합율을 변화시키면서 실내시험을 실시하였다. 제체재료의 적합성 검토, 설계 및 해석에 필요한 기초자료를 제공하기위해 다짐시험 및 표준삼축압축시험을 실시하여 시멘트혼합율에 따른 강도, 변형에 따른 응력 및 거동특성 등을 분석하였다.

혀에 발생한 선편평세포암의 증례보고 (A CASE REPORT OF ADENOSQUAMOUS CELL CARCINOMA INVOLVING SUBMUCOSAL GLAND AND TONGUE)

  • 방만혁;이동근;엄인웅;민승기;권혁도;김은철
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제16권2호
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    • pp.196-201
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    • 1994
  • One case of an unusual form of carcinoma involving the submucosal gland and duct of tongue was reported and reviewed. According to Gerughty et al(1968) four distinct component parts were classified : ductal carcinoma in situ(involvement of the ductal epithelium by in situ carcinomatous changes), squamous cell carcinoma, and a mixed carcinoma(combination of glandular and squamous characteristics and occasionally consisted of large nests composed of "glassy" cell). This tumor was fond to be extremely aggressive and highly malignant. The histopathologic features and the clinical behavior of this tumor were sufficiently distinctive to warrant the designation adenosquamous carcinoma : exhibit concomitant glandular and squamous neoplasm. The mode of therapy was evaluated and the treatment of choice appears to be radical surgery. So, we has done the radical neck dissection and partial glossectomy. However, the limited number of cases indicated that collection and subsequent analysis of additional cases must be performed before any definitive conclusion can be drawn.

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Radiographic manifestations of fibroblastic osteosarcoma: A diagnostic challenge

  • Tahmasbi-Arashlow, Mehrnaz;Barnts, Kelcie Louise;Nair, Madhu K.;Cheng, Yi-Shing Lisa;Reddy, Likith V.
    • Imaging Science in Dentistry
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    • 제49권3호
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    • pp.235-240
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    • 2019
  • Osteosarcoma is the most common primary bone tumor after plasma cell neoplasms. Osteosarcoma has diverse histological features and is characterized by the presence of malignant spindle cells and pluripotent neoplastic mesenchymal cells that produce immature bone, cartilage, and fibrous tissue. Osteosarcoma most frequently develops in the extremities of long bones, but can occur in the jaw in rare cases. The clinical and biological behavior of osteosarcoma of the jaw slightly differs from that of long-bone osteosarcoma. The incidence of jaw osteosarcoma is greater in the third to fourth decades of life, whereas long-bone osteosarcoma mostly occurs in the second decade of life. Osteosarcoma of the jaw has a lower tendency to metastasize and a better prognosis than long-bone osteosarcoma. Radiographically, osteosarcoma can present as a poorly-defined lytic, sclerotic, or mixed-density lesion with periosteal bone reaction response. Multi-detector computed tomography is useful for identifying the extent of bone destruction, as well as soft tissue involvement of the lesion. The current case report presents a fibroblastic osteosarcoma involving the left hemimandible with very unusual radiographic features.