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Heart disease is the leading cause of mortality in the U.S. with approximately 610,000 people dying every year. Effective therapies for many cardiac diseases are lacking, largely due to an incomplete understanding of their genetic basis and underlying molecular mechanisms. Zebrafish (Danio rerio) are an excellent model system for studying heart disease as they enable a forward genetic approach to tackle this unmet medical need. In recent years, our team has been employing electrocardiogram (ECG) as an efficient tool to study the zebrafish heart along with conventional approaches, such as immunohistochemistry, DNA and protein analyses. We have overcome various challenges in the small size and aquatic environment of zebrafish in order to obtain ECG signals with favorable signal-to-noise ratio (SNR), and high spatial and temporal resolution. In this paper, we highlight our recent efforts in zebrafish ECG acquisition with a cost-effective simplified microelectrode array (MEA) membrane providing multi-channel recording, a novel multi-chamber apparatus for simultaneous screening, and a LabVIEW program to facilitate recording and processing. We also demonstrate the use of machine learning-based programs to recognize specific ECG patterns, yielding promising results with our current limited amount of zebrafish data. Our solutions hold promise to carry out numerous studies of heart diseases, drug screening, stem cell-based therapy validation, and regenerative medicine.

In this study, we analyze the economic effects from the Korean Astronaut Program (KAP) and the subsequent Science Culture Diffusion Activity (SCDA). Korea has had a huge practical effect on the development of science and technology and has increased international awareness of Korea by producing Korea's first astronaut. There has also been a large, ripple effect on space related industries. In addition, the KAP has exercised a far-reaching influence on Korean society and culture by boosting all science and engineering and inspiring national pride. After the KAP, astronauts' outreach activities, such as lectures for the general public; interviews on television, newspapers and magazines; participating in children's science camps; and distributing publications and DVDs about astronaut program for general public, were instituted for diffusing science culture. Thus, positive effects such as the promotion of Korea's level of technology, student interest in science and engineering fields, and the expansion of the industrial base were reinforced after the KAP. This study is aimed at evaluating the economic significance and the value of return through analyzing the effects of the KAP and the subsequent Science Culture Diffusion Activity.

PURPOSE This study was designed to evaluate the effect of microgravity on the diurnal variation of intraocular pressure (IOP). METHODS IOPs were measured with the pressure phosphene tonometer in 1 subject (the first Korean astronaut) during spaceflight. IOPs were measured every 3 hours during day time (6 times per day) at 2 separate days in space with 3 repeated measurements at each time on both eyes. A total of 72 measurements were obtained during spaceflight. To obtain control IOP data, IOP was measured using the same protocol on ground before spaceflight. RESULTS Mean IOP increased by 26.3% during spaceflight compared with that on ground [16.47 ± 0.60 (SD) mm Hg vs. 13.04 ± 0.74 mm Hg, P

The paper presents an overview of the scientific space experiments in the Korean Astronaut Program (KAP) that were conducted on the International Space Station (ISS), beginning with launch of the Soyuz TMA-12 spacecraft with the first Korean astronaut and two Russian astronauts on April 8, 2008 and returning to Earth on April 19, 2008. During the 10 days aboard the ISS, the Korean astronaut successfully completed thirteen scientific experiments in biology, life science, material science, earth science, and system engineering, five educational space experiments, and three kinds of international collaboration experiments. These experiments were the first Korean manned space experiments and these missions were the first steps toward the manned space exploration by Korea. In this paper, we briefly discuss the descriptions, conduct, and results of the space experiments and discuss future plans. In addition, the lessons learned with respect to the performing of these manned space experiments on the ISS are presented.

We present the experimental study to realize a DNA separation chip using asymmetrically-switched nonuniform electric fields. The DNA separation chip redistributes DNA molecules within a specific area based on the size- and field-dependent nonlinearity of DNA drift velocity. The present chip is composed of a width variable channel to distribute nonuniform electric field, a DNA loading slit and a pair of electrodes to apply electric field. We focus on the design of DNA separation chips with identifying the nonlinearity of DNA drift velocity using three different DNA molecules (11.1kbp, 15.6kbp, and 48.5kbp) in the chips. It is demonstrated that different size of DNA shows different net migration in different direction under the asymmetrically-switched n onuniform electric field.기호설명 E 전기장 T 전기장 인가 주기 M DNA 분자의 크기 1. 서론 본 연구은 DNA 분리소자에 관한 것으로, 채널 내에 형성된 불균일한 전기장의 방향이 변함에 따라, DNA는 그 6cm크기에 따라 알짜이동 방향과 속도가 달라지게 된다. 본 논문에서는 이론적으로 제시된 바 있는 (1)이러한 래칫(ratchet) 효과를 실험적으로 검증하였다. 제안한 DNA분리소자(Fig. 1)에서는 비대칭 교차전기장(Fig. 2) 6mm미소유로을 양단에 인가하고 미소유로의 폭을 변화시켜 불균일 전기장을 형성하였다. 기존의 전기영동 소자

This storytelling course will bring, in meaningful terms, insightful concepts, methods and tools that are used in the air and space domains. HCI for complex engineered systems challenges conventional HCI solutions to propose new kinds of approaches that turn out to be very useful for solving HCI complex problems. Participants will design devices usable on Earth using accumulated knowledge and tips from aerospace experience. Creativity, in the sense of synthesis and integration, and design thinking will be at the center of this course, where participants will learn how to state and solve a complex design problem, and deliver the resulting product.

This paper presents the experimental study to realize a DNA separation chip based on the self-focusing effect in a micropillar array. The present self-focusing chip redistributes DNA molecules within a specific area of micropillar arrays based on the size- and field-dependent nonlinearity of DNA drift velocity. Compared to conventional electrophoresis chips, the present self-focusing chip reduces a substantial amount of the separation channel length, the influence of sample starting location, and the necessity of time-consuming continuous monitoring process. We focus on the design of DNA self-focusing chips, with identifying the nonlinearity of DNA drift velocity using three different DNA molecules including λ DNA(48.5 kbp), micrococcus DNA(115 kbp), and T4 DNA(169.8 kbp) in microfabricated test chips. It is demonstrated that the present DNA self-focusing chips have potentials not only for the miniaturization of DNA analysis systems, but also for the tunable capability of the target DNA size to be separated, trapped and extracted.

This paper presents an integrated deoxyribose nucleic acid (DNA) trapping and extraction microchip based on the electrophoresis using periodically crossed electric fields in the micropillar array. The extraction microchip, integrated with a micropillar array, microchannels, nano-gap entropic barriers, loading and unloading windows, has been fabricated by a 3-mask microfabrication process. Using the electric field crossed at 120°, the microchip is designed to trap the DNA molecules, whose reorientation time is longer than the period of the crossed field, within the micropillars distributed at 60° direction. In the fabricated extraction microchip, three different DNA molecules, including λ DNA (48.5 kbp), micrococcus DNA (115 kbp) and T4 DNA (168.9 kbp) show the reorientation times of 4.80 ± 0.44 s, 7.12 ± 0.75 s and 9.71 ± 0.30 s, respectively, at the crossed electric field of 6.25 V/cm. Among three DNA molecules, T4 DNA could not come out of the micropillar array for the electric field of 6.25 V/cm crossed at the period of 10 s. We have demonstrated that the present DNA extraction microchip separates DNA molecules larger than a critical value, which can be adjusted by the period of the electric field across the micropillar array.

This paper presents the experimental study to realize a DNA separation chip based on the self-focusing effect in a microfabricated PDMS chip. The present self-focusing chip redistributes DNA molecules within a specific area based on the size- and field-dependent nonlinearity of DNA drift velocity. Compared to conventional electrophoresis chips, the present self-focusing chip offers the advantages of simple structure, short separation channel length, and starting-point independent DNA separation. We focus on the design of DNA self-focusing chips, with identifying the nonlinearity of DNA drift velocity using three different DNA molecules (11.1kbp, 15.6kbp, and 48.5kbp) in test chips. It is demonstrated that the present DNA self-focusing chips have potentials not only for the miniaturization of DNA analysis systems, but also for the tunable capability of the target DNA size to be separated, trapped and extracted.

This paper presents the first experimental study to realize a DNA separation chip based on the self-focusing effect in a micropillar array. The present self-focusing chip redistributes DNA molecules within a specific area of micropillar arrays based on the size- and field-dependent nonlinearity of DNA drift velocity. Compared to conventional electrophoresis chips, the present self-focusing chip reduces a substantial amount of the separation channel length, the influence of sample starting location, and the necessity of time-consuming continuous monitoring process. We focus on the design of DNA self-focusing chips, with identifying the nonlinearity of DNA drift velocity using three different DNA molecules including /spl lambda/ DNA (48.5 kbp), micrococcus DNA (115 kbp), and T4 DNA (169.8 kbp) in microfabricated test chips. It is demonstrated that the present DNA self-focusing chips have potentials not only for the miniaturization of DNA analysis systems, but also for the tunable capability of the target DNA size to be separated, trapped and extracted.

We present a novel cell counter using a fixed control volume and double electrical sensing zones at the inlet and outlet of the control volume. The present cell counter measures cell concentration based on the difference of the counted cell numbers from the double electrical sensing zones at inlet and outlet of the fixed control volume. In the experimental study, we use the RBC samples of three different concentrations and compare the results from the fabricated device with those from hemacytometer. Using the fabricated devices, we make two different measurements: 1) Cell concentration measurement using single electrical sensing at a fixed flow-rate of 10 /spl mu/l/min.; 2) Cell concentration measurement using double electrical sensing with the fixed control volume of 22.9/spl plusmn/0.98 /spl mu/l. Compared to hemacytometer, the single and double electrical sensing methods show the maximum errors of 20.3% and 16.1%, respectively, which are in the measurement error range of hemacytometer. We also observe that the present cell counter has an immunity for flow-rate change.