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Hybridization by an Electrical Force and Electrochemical Genome Detection Using an Indicator-free DNA on a Microelectrode-array DNA Chip

  • Choi, Yong-Sung;Lee, Kyung-Sup;Park, Dae-Hee
    • Bulletin of the Korean Chemical Society
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    • v.26 no.3
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    • pp.379-383
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    • 2005
  • This research aims to develop DNA chip array without an indicator. We fabricated microelectrode array by photolithography technology. Several DNA probes were immobilized on an electrode. Then, indicator-free target DNA was hybridized by an electrical force and measured electrochemically. Cyclic-voltammograms (CVs) showed a difference between DNA probe and mismatched DNA in an anodic peak. Immobilization of probe DNA and hybridization of target DNA could be confirmed by fluorescent. This indicator-free DNA chip microarray resulted in the sequence-specific detection of the target DNA quantitatively ranging from $10^{-18}\;M\;to\;10^{-5}$ M in the buffer solution. This indicator-free DNA chip resulted in a sequence-specific detection of the target DNA.

Experimental Investigation on Key Parameters in Air-powered Needle-free Injection System for Skin Treatment (피부 치료를 위한 공압식 무침 주사 시스템의 주요 인자에 관한 실험적 연구)

  • Kim, Jung Kyung;Mohizin, Abdul;Lee, Seung Ku
    • Journal of the Korean Society of Visualization
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    • v.16 no.1
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    • pp.42-47
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    • 2018
  • A needle-free injector is one of the new non-invasive players in impregnating the biological barriers. It is considered as the next phase in drug delivery and therapeutic applications. One of the major fields of application is in skin remodeling procedures. Although many studies were carried out in understanding the principle in the needle-free injection procedure, fewer studies were done with the aim of therapeutic applications. In the present study, we tried to identify key parameters that affect the jet divergence and peak stagnation pressure on the skin surface in a conventional needle-free injector for skin treatment. A summary of the working principle and effect of the key parameters are presented.

Modelling of evaporation from free water surface

  • Song, Wei-Kang;Chen, Yibo
    • Geomechanics and Engineering
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    • v.21 no.3
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    • pp.237-245
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    • 2020
  • The process of evaporation from free water surface was simulated in a large scale environmental chamber under various controlled atmospheric conditions and also was modelled by a new mass transfer model. Six evaporation tests were conducted with increasing wind speed and air temperature in the environmental chamber, and hence the effect of atmosphere parameters on the evaporation process and the corresponding response of water were investigated. Furthermore, based on the experiment results, seven general types of mass transfer models were evaluated firstly, and then a new model consisted of wind speed function and air relative humidity function was proposed and validated. The results show that the free water evaporation is mainly affected by the atmospheric parameters and the evaporation rate increases with the increasing air temperature and wind speed. Both the air and soil temperatures are affected by the energy transformation during water evaporation. The new model can satisfactorily describe the evaporation process from free water surface under different atmospheric conditions.

Disease Free Survival among Molecular Subtypes of Early Stage Breast Cancer between 2001 and 2010 in Iran

  • Najafi, Behrouz;Anvari, Saeid;Roshan, Zahra Atrkar
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5811-5816
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    • 2013
  • Background: Breast cancer is the most common cancer among women. Molecular subtypes are important in determining prognosis. This study evaluated five-year disease-free survival among four molecular subtypes in patients with early stages of breast cancer. Materials and Methods: In this retrospective descriptive-analytical study, information on patients with breast cancer between 2001-2010 was evaluated. Five hundred ninety two patients in the early stages of breast cancer (stages 1 and 2) were selected to undergo anthracycline-based chemotherapy. Relapse, death or absence (censor) were considered as the end of the study. Patients based on ER, PR and HER-2 expression were divided into four subtypes (luminal A, luminal B, HER-2 enriched and triple negative). Information based upon questionnaire was analysed. To show the patients survival rate, life table and Kaplan-Meyer methods were used, and for comparing mean survival among different groups, the Log-Rank test was utilized. Results: Mean age at diagnosis was $47.9{\pm}9.6$. Out of the 592 patients, 586 were female (99%) and 6 were male (1%). Considering breast cancer molecular subtypes, 361 patients were in the luminal A group (61%), 49 patients in the luminal B group (8.3%), 48 patients in the HER-2 enriched group (8.1%) and 134 in the triple negative group (22.6%). Mean disease-free survival was 53.7 months overall, 55.4 months for the luminal A group, 48.3 months for the luminal B group, 43 months for the HER-2enriched group and 54.6 months for the triple negatives. Disease free survival differed significantly among the molecular subtypes (p value=0.0001). Conclusions: The best disease-free survival rate was among the luminal A subgroup and the worst disease-free survival rate was among the HER-2 enriched subgroup. Disease free survival rate in the HER-2 positive groups (luminal B and HER-2 enriched) was worse than the HER-2 negative groups (luminal A and triple negative).

Muscle Free Flap Transplantation in Chronic Osteomyelitis of the Lower Extremities (하지의 만성 골수염에 시행된 근 유리 판 이식술)

  • Lee, Jun-Mo;Song, Kwang-Hun;Park, Jong-Hyuk
    • Archives of Reconstructive Microsurgery
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    • v.18 no.2
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    • pp.49-54
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    • 2009
  • Purpose: To evaluate the result of muscle free flap transplantation in chronic osteomyelitis of the tibia and calcaneus occurred from open fractures and exposed bones and internal fixatives. Materials and Methods: The free muscle flap were transferred in the tibia and calcaneus and followed up average 7.3 years at the department of orthopedic surgery from March 1997 to September 2009. Six patients were male and 1 case female averaged 50.3 years of age. Two latissimus dorsi myocutaneous free flaps were transplanted to the exposed 2/3 of the tibia with soft tissue defect, one rectus abdominis muscle free flap to the mid 1/3 of the tibia and four gracilis muscle free flaps to the distal 1/3 of the tibia and calcaneus. Results: At average 7.2 years follow-up, all of the 7 cases obtained solid bone union in the X-ray and kept sound soft tissues without pus discharges. The overall result of bone union, healed soft tissues defect and normal knee and ankle joint range of motion were excellent. Conclusion: The free muscle flap transferred to the chronic osteomyelitis of the tibia and calcaneus showed excellent results in bone union and eradication of the pus forming bacteria by its abundant blood flow.

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Analysis of Performance on Asymmetric LED Lens Design Using Three-Dimensional Free-Form Surface Expression (3차원 자유곡면식을 이용한 LED 비대칭 렌즈 설계 및 성능 비교 분석)

  • Lee, Chang Soo;Lee, Soo Young;Hyun, Dong Hoon
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.26 no.3
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    • pp.328-336
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    • 2017
  • The exit surface of a lens is designed using a three-dimensional free-form expression in order to easily modify a curved surface. This enables the design of numerical values and mathematical things using three-dimensional free-form expression, and enhances precision because it can be fine-tuned via numerical control. The standard of "Classification of Luminaire Light Distribution" for outdoor lighting fixtures by IESNA is adopted in order to examine the correlation between three-dimensional free-form surface expression and lighting performance. The variation of light distribution type and range is analyzed using the values of maximum light intensity and 50% light intensity. The actual tolerance occurs owing to parameters such as the thickness of the lens, the distance between LEDs, and the movement of the center of the incident surface; the effects of changes in these parameters on the performance are compared and analyzed.