• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2293-2298
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• 2010

Focused electrospray (FES) deposition method is presented for matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. FES ion optics consists of two cylindrical focusing electrodes capped with a truncated conical electrode through which an electrospray emitter passes along the cylindrical axis. A spray of charged droplets is focused onto a sample well on a MALDI target plate under atmospheric pressure. The shape and size distributions of matrix crystals are visualized by scanning electron microscope and the mass spectra are obtained by time-of-flight mass spectrometry. Angiotensin II, bradykinin, and substance P are used as test samples, while $\alpha$-cyano-4-hydroxycinnamic acid and dihydroxybenzoic acid are employed as matrices. FES of a sample/matrix mixture produces fine crystal grains on a 1-3 mm spot and reproducibly yields the mass spectra with little shot-to-shot and spot-to-spot variations. Although FES greatly stabilizes the signals, the space charge due to matrix ions limits the detection sensitivity of peptides. To avoid the space charge problem, we adopted a dual FES/FES mode, which separately deposits matrix and sample by FES in sequence. The dual FES/FES mode reaches the detection sensitivity of 0.88 amol, enabling ultrasensitive of peptides by homogeneously depositing matrix and sample under atmospheric pressure.

• 전자공학회논문지A
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• 제33A권5호
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• pp.132-141
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• 1996

The pixelated phase grating has been studied as a kind of diffraction gratings splitting and input beam into multiple spots. It consists of regular size cells which produce phase delays, and each cell provokes the phase delay up to sixteen levels. We have compared and analyzed the characteristics of multi-level phase gratings, laying streess on efficiency and resulted pattern. Experimental resutls obtained form fabricated grating have been presented, and the real-time method using a liquid-crystal spatial light modulator has been demonstrated through experiments. Gratings making meams with specific intensities have been designed and optical images have been generated by them. In order to specific intensities have been designed and optical images have been genrated by them. In order to decide the phase delay of each cell, optimization conditon consists of diffraction efficiency and target values. One period of phase gratings fabricated with surface relief was less than 256${\mu}m{\times}256{\mu}m$ and size of each cell was 1${\mu}m{\times}1{\mu}m$ surface relief grating has been made by coating photoresist on the glass plate, writing information pattern by Ar laser and developing it. in the experiment for real-tiem processing liquid-crystal display of epson video projector has been used.

• Biomolecules & Therapeutics
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• 제22권5호
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• pp.445-452
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• 2014

The purpose of this study was to investigate the therapeutic effects of DA-9801, an optimized extract of Dioscorea species, on diabetic peripheral neuropathy in a type 2 diabetic animal model. In this study, db/db mice were treated with DA-9801 (30 and 100 mg/kg, daily, p.o.) for 12 weeks. DA-9801 reduced the blood glucose levels and increased the withdrawal latencies in hot plate tests. Moreover, it prevented nerve damage based on increased nerve conduction velocity and ultrastructural changes. Decrease of nerve growth factor (NGF) may have a detrimental effect on diabetic neuropathy. We previously reported NGF regulatory properties of the Dioscorea genus. In this study, DA-9801 induced NGF production in rat primary astrocytes. In addition, it increased NGF levels in the sciatic nerve and the plasma of type 2 diabetic animals. DA-9801 also increased neurite outgrowth and mRNA expression of Tieg1/Klf10, an NGF target gene, in PC12 cells. These results demonstrated the attenuation of diabetic peripheral neuropathy by oral treatment with DA-9801 via NGF regulation. DA-9801 is currently being evaluated in a phase II clinical study.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5977-5981
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• 2015

Background: Worldwide, breast cancer is the most common cancer diagnosed among women and a leading cause of cancer deaths. The age of onset in Iran has become reduced by a decade for unknown reasons. Herceptin, a humanized monoclonal antibody, is a target therapy for breast cancer cells with over expression of HER2-neu receptors, but it is an expensive drug with only 20% beneficial rate of survival. This study introduces a novel approach to enhance the efficacy of this drug through immunoconjugation of the antibody to botulinum toxin. Decreasing the cost and adverse effects of the antibody were secondary goals of this study. Materials and Methods: Botulinum toxin was conjugated with Herceptin using heterobifunctional cross linkers, succinimidyl acetylthiopropionate (SATP) and sulfo-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) according to the supplier's guidelines and tested on two breast cancer cell lines: SK-BR-3 and BT-474. Toxin and Herceptin were also used separately as controls. The cytotoxicity assay was also performed using the new bioconjugate on cultured cells with Alamar blue and a fluorescence plate reader. Results: Herceptin-Toxin bioconjugation significantly improved Herceptin efficacy on both breast cancer cell lines when compared to the control group. Conclusions: Toxin-Herceptin bioconjugation can be a potential candidate with increased efficiency for treating breast cancer patients with over expression of the HER2 receptor.

• Journal of Advanced Marine Engineering and Technology
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• 제37권8호
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• pp.893-904
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• 2013

NSGA-II와 함께 크리깅 메타모델기반 다목적최적설계 전략을 3차원 CFD 시뮬레이션을 통해 액셜 피스톤 펌프의 밸브 플레이트 형상을 최적화하는데 적용하였다. 펌프의 압력 변동을 저감하고 수력 효율을 최대화하기 위한 최적설계 과정은 두 단계, 즉 (1) 밸브 플레이트 상의 6개 형상 설계 변수를 선정하고 각 설계변수의 변화에 따른 CFD 해석을 수행하며, (2) CFD 데이터를 이용한 NSGA-II에 기반한 다목적최적설계 접근방식으로 최소 맥동 압력과 펌프 효율 설계에 대해 파레토 프론트를 평가하는 것으로 구성된다. 이들 결과로부터 최소 맥동 압력을 가지며 액셜 피스톤 펌프의 목표 효율에 도달하는 최적 절충해를 선택할 수 있었다.

• Geomechanics and Engineering
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• 제23권4호
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• pp.339-349
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• 2020

This study investigates the feasibility of using the results of the UPV (ultrasonic pulse velocity) test to assess the UCS (unconfined compressive strength) of unsaturated soil. A series of laboratory tests was conducted on samples of unsaturated lateritic soils of northern Taiwan. Specifically, the unconfined compressive test was combined with the pressure plate test to obtain the unconfined compressive strength and its matric suction (s) of the samples. Soil samples were first compacted at the designated water content and subsequently subjected to the wetting process for saturation and the following drying process to its target suction using the apparatus developed by the authors. The correlations among the UCS, s and UPV were studied. The test results show that both the UCS and UPV significantly increased with the matric suction regardless of the initial compaction condition, but neither the UCS nor UPV obviously varied when the matric suction was less than the air-entry value. In addition, the UCS approximately linearly increased with increasing UPV. According to the investigation of the test results, simplified methods to estimate the UCS using the UPV or matric suction were established. Furthermore, an empirical formula of the matric suction calculated from the UPV was proposed. From the comparison between the predicted values and the test results, the MAPE values of UCS were 4.52-9.98% and were less than 10%, and the MAPE value of matric suction was 17.3% and in the range of 10-20%. Thus, the established formulas have good forecasting accuracy and may be applied to the stability analysis of the unsaturated soil slope. However, further study is warranted for validation.

• Nutrition Research and Practice
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• 제6권4호
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• pp.366-374
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• 2012

In order to create a worker-friendly environment for institutional foodservice, facilities operating with a dry kitchen system have been recommended. This study was designed to compare the work safety and work environment of foodservice between wet and dry kitchen systems. Data were obtained using questionnaires with a target group of 303 staff at 57 foodservice operations. Dry kitchen facilities were constructed after 2006, which had a higher construction cost and more finishing floors with anti-slip tiles, and in which employees more wore non-slip footwear than wet kitchen (76.7%). The kitchen temperature and muscular pain were the most frequently reported employees' discomfort factors in the two systems, and, in the wet kitchen, "noise of kitchen" was also frequently reported as a discomfort. Dietitian and employees rated the less slippery and slip related incidents in dry kitchens than those of wet kitchen. Fryer area, ware-washing area, and plate waste table were the slippery areas and the causes were different between the functional areas. The risk for current leakage was rated significantly higher in wet kitchens by dietitians. In addition, the ware-washing area was found to be where employees felt the highest risk of electrical shock. Muscular pain (72.2%), arthritis (39.1%), hard-of-hearing (46.6%) and psychological stress (47.0%) were experienced by employees more than once a month, particularly in the wet kitchen. In conclusion, the dry kitchen system was found to be more efficient for food and work safety because of its superior design and well managed practices.

• 한국구조물진단유지관리공학회 논문집
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• 제24권2호
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• pp.1-8
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• 2020

원자력발전소와 같은 발전플랜트 시설의 경우 건물 자체뿐만 아니라 내부에 설치된 비구조요소의 내진안정성 또한 중요하다. 특히, 전기기기가 부착되는 캐비닛 구조물 등은 지진에 대비하여 기능적 안전성이 확보되어야 한다. 이에 따라 본 연구에서는 기존 발전플랜트 내부에서 운용 중인 전기기기 캐비닛 구조물의 동특성을 파악하고, 동적거동 시 발생되는 응답 수준을 분석하였다. 그리고 내진보강 방법 중 제진 방식을 적용하기 위해 강재 플레이트 댐퍼를 채택하고 대상기기의 크기에 적합하게 조정하였다. 또한, 최적의 보강방안을 도출하기 위해 부착위치에 따른 변수를 설정하고 보강 전·후의 지진동 입력에 의한 응답에 대하여 분석하는 연구를 수행하였다.

• Food Science and Biotechnology
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• 제16권6호
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• pp.1072-1077
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• 2007

Bacterial endospores, especially those of Bacillus and Clostridium genera, are the target of sterilization in various foods. We used Bacillus subtilis ATCC 6633 spores to screen novel antimicrobial substances against spores from medicinal plants. We collected 79 types of plant samples, comprising 42 types of herbs and spices and 37 types of medicinal plants used in traditional medicine in Korea and China. At a concentration of 1%(w/v), only 14 of the ethanol extracts exhibited antimicrobial activity against B. subtilis spores of at least 90%. Crude extracts of Torilis japonica, Gardenia jasminoides, Plantago asiatica, Fritllaria, and Arctium lappa showed particularly high sporicidal activities, reducing the spore count by about 99%. Consideration of several factors, including antimicrobial activity, extraction yields, and costs of raw materials, resulted in the selection of T. japonica, G. jasminoides, A. lappa, and Coriandrum sativum for the final screening of novel antimicrobial substances. Verification tests repeated 10 times over a 4-month period showed that the ethanol extract of T. japonica fruit reduced aerobic plate counts of B. subtilis spores the most, from $10^7$ to $10^4\;CFU/mL$ (99.9%) and with a standard deviation of 0.21%, indicating that this fruit is the most suitable for developing a novel antimicrobial substance for inactivating B. subtilis spores.

• 센서학회지
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• 제7권2호
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• pp.90-96
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• 1998

Cross capacitor 원리를 이용하여 $1.95{\pm}0.5\;mm$ 이하의 미소변위를 비접촉으로 정확하게 측정할 수 있는 새로운 전기용량 센서를 설계 제작하였다. 전극의 구조는 센서와 측정 대상체가 각각 하나의 전극으로 작용하여야 하는 기존의 2-전극형 및 3-전극형 센서들이 지니고 있는 단점을 보완하기 위하여 2개의 전극(high, low전극)을 센서의 면에 형성한 4-전극형 센서로 제작하였다. 센서의 전극은 직경 17 mm 두께 0.7 mm인 사파이어 평행원판위에 구리를 사용하여 전극간 간격유지를 0.2 mm로 일정하게 함과 동시에 완전대칭을 이루도록 제작하였다. 따라서 이 센서는 측정대상체가 금속, 비금속에 관계없이 센서와 측정대상체와의 미소변위 및 간격을 측정 할 수가 있다. 측정범위 $1.95{\pm}0.5\;mm$에서의 correlation coefficient는 0.9987, $1.95{\pm}0.25\;mm$에서는 0.9995로 측정되었다.