• Archives of Pharmacal Research
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• v.27 no.2
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• pp.127-135
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• 2004

Multiple drug administration is common in elderly, HIV, and cancer patients. Such treatments may result in drug-drug interactions due to interference at the metabolic enzyme level, and due to modulation of transporter protein functions. Both kinds of interference may result in altered drug distribution and toxicity in the human body. In this review, we have dealt with drug-drug interactions related to the most studied human transporter, P-glycoprotein. This transporter is constitutively expressed in several sites in the human body. Its function can be studied in vitro with different cell lines expressing P-glycoprotein in experiments using methods and equipment such as flow cytometry, cell proliferation, cell-free ATP as activity determination and Transwell culture equipment. In vivo experiments can be carried out by mdr1a(-/-) animals and by noninvasive methods such as NMR spectrometry. Some examples are also given for determination of possible drug-drug interactions using the above-mentioned cell lines and methods. Such preclinical studies may influence decisions concerning the fate of new drug candidates and their possible dosages. Some examples of toxicities obtained in clinics and summarized in this review indicate careful consideration in cases of polypharmacy and the requirement of preclinical studies in drug development activities.

• Structural Monitoring and Maintenance
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• v.9 no.3
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• pp.259-270
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• 2022

This study explores the use of the recently developed "strain-sensing smart skin" (S⁴) method for noncontact strain measurements on cement-based samples. S⁴ sensors are single-wall carbon nanotubes dilutely embedded in thin polymer films. Strains transmitted to the nanotubes cause systematic shifts in their near-infrared fluorescence spectra, which are analyzed to deduce local strain values. It is found that with cement-based materials, this method is hampered by spectral interference from structured near-infrared cement luminescence. However, application of an opaque blocking layer between the specimen surface and the nanotube sensing film enables interference-free strain measurements. Tests were performed on cement, mortar, and concrete specimens with such modified S⁴ coatings. When specimens were subjected to uniaxial compressive stress, the spectral peak separations varied linearly and predictably with induced strain. These results demonstrate that S⁴ is a promising emerging technology for measuring strains down to ca. 30 𝜇𝜀 in concrete structures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.37-39
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• 2022

As the COVID-19 pandemic hits the world, the Tokyo Olympics in 2021 will be held behind closed doors. Some broadcasters showed the heart rate of the players in real time using image processing-based non-contact measurement to convey the vividness of the scene on TV. However, since the non-contact model uses changes in the skin color of the players' faces according to blood circulation as a parameter, there is a possibility that errors may occur due to interference factors such as natural light or glasses. Therefore, in this paper, the non-contact heart rate measurement model and the contact heart rate measurement model are tested in an environment free from interference and their accuracy is analyzed.

• Journal of the Korean Society for Nondestructive Testing
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• v.13 no.2
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• pp.20-30
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• 1993

Electric Speckle Pattern Interferometry (ESPI) using a CW-laser, a video system and an image processor was applied to the thermal coefficient measurements on free thermal expansions at high temperatures : ESPI provides the distribution of in-plane displacement resolved in a preselected direction. ESPI retains the merits of little or no surface preparation, no contact with the surface and the real-time presentation of interference fringes. Appling ESPI at high temperatures, several problem which caused the reduction of fringe visibility were encountered. The problem on the turbulence in the hot air surrounding high temperature objects will be solved by using a vacuum chamber. The background radiations from the objects were suppressed considerably by an interference filter. The problem on the oxidation of the object surface could't be solved. The interference fringe, whose spacings were calculated by FFT to avoid human error, were observable up to $800^{\circ}C$. The results measured by ESPI were nearly equal to the data which have already been published, up to about $800^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.4
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• pp.456-464
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• 2010

RNA interference (RNAi) is an acknowledged useful and effective tool to study gene function in various cells. Here, we suppressed the Connexin 43 (Cx 43) gene expression during in vitro development of ovine pre-implantation embryos using the RNAi method. The 353 bp Cx 43 double-stranded RNA was microinjected into in vitro fertilized ovine zygotes, and the levels of target mRNA and protein were investigated. Control groups included uninjected zygotes or those injected with RNase-free water. The dsRNA injection resulted in the specific reduction of Cx 43 transcripts as analyzed by quantitative real-time RT-PCR and decreased protein levels as shown by Western blot analysis at the blastocyst stage. Microinjection of Cx 43 dsRNA led to 20.3%, 21.7% and 34.5% blastocyst rates and 19.2%, 37.5% and 41.3% hatched blastocyst rates in Cx 43 dsRNA-injected, water-injected and uninjected groups, respectively. Then the RNAi could not significantly affect cell number and cell death rates of blastocysts. Therefore, suppression of Cx 43 dsRNA and proteins did not apparently affect the development potential of ovine pre-implantation embryos but may play a role in embryo quality. RNAi technology is a promising approach to study gene function in early ovine embryogenesis.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.2
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• pp.46-54
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• 2007

We have fabricated and characterized MMI (Multimode Interference) coupled ring resonator with the total internal reflection mirrors and the semiconductor optical amplifier for the integration of the WDM (Wavelength Division Multiplexing) system. The TIR (Total Internal Reflection) mirrors were fabricated by self-aligned process and had losses of about 0.71 dB per mirror. Coupling in and out of a resonator was achieved using the extremely small MMI couplers. The MMI length and width used in the experiment were $119{\mu}m$ and $9{\mu}m$, respectively. The resulting FSR (Free Spectral Range) and on-off ratio were approximately 1.333 nm (162 GHz) and 13 dB, respectively.

• Journal of Sensor Science and Technology
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• v.22 no.2
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• pp.144-149
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• 2013

In this research, we developed a biosensor to detect lung cancer-specific biomarker using Anodic Aluminum Oxide (AAO) chip based on interference and nano surface plasmon resonance (nanoSPR). The nano-porous AAO chip was fabricated $2{\mu}m$ of pore-depth by two-step anodizing method for surface uniformity. NanoSPR has sensitivity to the refractive index (RI) of the surrounding medium and also provides simple and label-free detection when specific antibodies are immobilized to the Au-deposited surface of nano-porous AAO chip. To detect the lung cancer-specific biomarker, antibodies were immobilized on the surface of the chip by Self Assembled Monolayer (SAM) method. Since then lung cancer-specific biomarker was applied atop the antibodies immobilized layer. The specific reaction of the antigen-antibody contributed to the change in the refractive index that cause shift of resonance spectrum in the interference pattern. The Limit of Detection (LOD) was 1 fg/ml by using our nano-porous AAO biosensor chip.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.2 s.152
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• pp.198-209
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• 2007

In this paper, we present the gouging and collision-free tool-path generation for manufacturing model propellers using the 5-axis NC machine. Because it takes much time to generate tool-paths when we use general purpose CAD/CAM systems, a specific system would be necessary for marine propellers. Overall manufacturing process is composed of two steps: roughcut and finishcut steps. The roughcut is conducted using only 3-axis for efficient machining and the finishcut is done using 5-axis for avoiding collision. The tool-path that might happen to gouging is searched and the tool position is also decided for avoiding interference between the tool and the propeller blades. The present algorithm is applied extensively to the surface piercing propellers. Some results are demonstrated for its validation.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.19 no.1
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• pp.28-37
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• 2008

Objectives : This study was conducted in order to examine the reliability and validity of the Children's Color Trails Test (CCTT). The objective of the study was also to provide the Korean normative data for the CCTT. Methods : Normative samples consisted of 766 children and adolescents living in Seoul and aged from 5 to 15 years. Eighty children who were diagnosed with ADHD, based on the DSM-IV criterion, were recruited from Seoul National University Children's Hospital. Among them, 46 ADHD children were receiving medication, while 34 children were drug-free. Results : The scores of the CCTT were significantly correlated with those of the Stroop test. Three factors were extracted through factor analysis-visual tracking and cognitive flexibility, distractibility and susceptibility to interference, and simple attention and impulsivity. The completion time of the CCTT for all children tended to decrease as age increased. There were significant differences in the CCTT scores between the ADHD group receiving medication, the ADHD-drug free group and the normal groups. The CCTT also showed sound test-retest reliability. These results confirmed the reliability and validity of the CCTT. Finally, we provided the Korean normative data for the CCTT. Conclusion : These results suggest that the CCTT is a reliable and valid test, which can be used to assess frontal function related to child psychiatric disorders in Korean children.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8C
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• pp.655-662
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• 2012

In this work, we propose an airborne cognitive radio system that searches a new spectrum band to avoid a communication interruption due to the interference from many radar signals. We develop a method of fast spectrum sensing based on an effective frequency by recognizing the interfering radar as well as geographical information. This effective frequency is calculated by the free-space path loss between a base station and a fighter with the speed parameter. From our analysis, it is verified that the maximum frequency searching time is reduced by half by using our method.