• Title/Summary/Keyword: Hybrid functional

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Co-expression of a novel ankyrin-containing protein, rSIAP, can modulate gating kinetics of large-conductance calcium-activated potassium channel from rat brain.

  • Lim, Hyun-Ho;Park, Chul-Seung
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.45-45
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    • 2003
  • We isolated a novel ankyrin-repeat containing protein, rSIAP (rSlo Interacting Ankyrin-repeat Protein), as an interacting protein to the cytosolic domain of the alpha-subunit of rat large-conductance Ca$\^$2+/-activated K$\^$+/ channel (rSlo) by yeast two-hybrid screening. Affinity pull-down assay showed the direct and specific interaction between rSIAP and rSlo domain. The channel-binding proteins can be classified into several categories according to their functional effects on the channel proteins, i.e. signaling adaptors, scaffolding net, molecular tuners, molecular chaperones, etc. To obtain initial clues on its functional roles, we investigated the cellular localization of rSIAP using immunofluorescent staining. The results showed the possible co-localization of rSlo and rSIAP protein near the plasma membrane, when co-expressed in CHO cells. We then investigated the functional effects of rSIAP on the rSlo channel using electrophysiological means. The co-expression of rSIAP accelerated the activation of rSlo channel. These effects were initiated at the micromolar [Ca$\^$2+/]$\_$i/ and gradually increased as [Ca$\^$2+/]$\_$i/ raised. Interestingly, rSIAP decreased the inactivation kinetics of rSlo channel at micromolar [Ca$\^$2+/]$\_$i/, while the rate was accelerated at sub-micromolar [Ca$\^$2+/]$\_$i/. These results suggest that rSIAP may modulate the activity of native BK$\_$Ca/ channel by altering its gating kinetics depending on [Ca$\^$2+/]$\_$i/. To localize critical regions involved in protein-protein interaction between rSlo and rSIAP, a series of sub-domain constructs were generated. We are currently investigating sub-domain interaction using both of yeast two-hybrid method and in vitro binding assay.

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Synthesis of Reduced Graphene-metal Hybrid Materials via Ion-exchange Method and its Characterization (이온교환법에 의한 환원 그래핀-금속 하이브리드 소재의 합성 및 특성)

  • Park, Aeri;Kim, Sumin;Kim, Hyun;Han, Jong Hun
    • Journal of the Microelectronics and Packaging Society
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    • v.27 no.4
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    • pp.25-37
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    • 2020
  • In this study, hybridization of graphene oxide and metal was carried out by the functional groups containing oxygen and thermal treatment for reduction in order to enhance the electrical conductivity and magnetic properties of graphene materials. Graphene-metal hybrid materials were synthesized using the oxygen-containing functional groups (-OH, -COOH and so on) on the surface of graphene oxide by replacing them with metal ions via ion exchange method as well as thermal reduction. The metals used in this study were Fe, Ag, Ni, Zn, and Fe/Ag, and it was confirmed that metal particles of uniform size were well dispersed on the graphene surface through SEM, TEM, and EDS. All of the metal particles on the graphene surface had an oxide-crystalline structure. To check the electrical properties, sheet resistance of the rGO-metal hybrid sample was measured on the PET film made by the dip-coating, and the specific resistance was calculated by measuring the thickness of the specimen through SEM. As a result, the specific resistance was in the range of 2.14×10-5 and 3.5×10-3 ohm/cm.

Assessing Density Functional Theories to Compute the OH Stretching Frequencies of Water Molecules in Condensed Phases (응축상 물 분자의 OH 수축 진동수 계산을 위한 전자밀도 범함수 비교)

  • Kiyoung, Jeon;Mino, Yang
    • Journal of the Korean Chemical Society
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    • v.67 no.1
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    • pp.13-18
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    • 2023
  • We evaluate electron density functional theories for the computation of 0-1 and 1-2 transition energies of local OH stretching motion of water molecules in condensed phases. By examining thirteen density functionals and nine sets of basis functions, it was found that the optimal combination that predicts the transition energies highly correlated with those calculated by the coupled cluster theory, CCSD(T), is the hybrid density functional theory developed by Head-Gordon group, ωB97X(D)/6-31+G*.

Development and Evaluation of Hyaluronic Acid-Based Hybrid Bio-Ink for Tissue Regeneration

  • Lee, Jaeyeon;Lee, Se-Hwan;Kim, Byung Soo;Cho, Young-Sam;Park, Yongdoo
    • Tissue Engineering and Regenerative Medicine
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    • v.15 no.6
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    • pp.761-769
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    • 2018
  • BACKGROUND: Bioprinting has recently appeared as a powerful tool for building complex tissue and organ structures. However, the application of bioprinting to regenerative medicine has limitations, due to the restricted choices of bio-ink for cytocompatible cell encapsulation and the integrity of the fabricated structures. METHODS: In this study, we developed hybrid bio-inks based on acrylated hyaluronic acid (HA) for immobilizing bio-active peptides and tyramine-conjugated hyaluronic acids for fast gelation. RESULTS: Conventional acrylated HA-based hydrogels have a gelation time of more than 30 min, whereas hybrid bio-ink has been rapidly gelated within 200 s. Fibroblast cells cultured in this hybrid bio-ink up to 7 days showed >90% viability. As a guidance cue for stem cell differentiation, we immobilized four different bio-active peptides: BMP-7-derived peptides (BMP-7D) and osteopontin for osteogenesis, and substance-P (SP) and Ac-SDKP (SDKP) for angiogenesis. Mesenchymal stem cells cultured in these hybrid bio-inks showed the highest angiogenic and osteogenic activity cultured in bio-ink immobilized with a SP or BMP-7D peptide. This bio-ink was loaded in a three-dimensional (3D) bioprinting device showing reproducible printing features. CONCLUSION: We have developed bio-inks that combine biochemical and mechanical cues. Biochemical cues were able to regulate differentiation of cells, and mechanical cues enabled printing structuring. This multi-functional bio-ink can be used for complex tissue engineering and regenerative medicine.

A decision making framework model for the selection of a RP using hybrid multiple attribute decision making techniques (3차원 조형장비 선정을 위한 복합 다요소 의사결정 구조 모델 개발에 관한 연구)

  • Byun, Hong-Seok
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.7 no.3
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    • pp.87-95
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    • 2008
  • The purpose of this study is to provide a decision support to select an appropriate rapid prototyping(RP) machine that suits the application of a part. Selection factors include concept model, form/fit/functional model, pattern model for molding, material property, build time and part cost that greatly affect the performance of RP machines. However, the selection of a RP is not an easy decision because they are uncertain and vague. For this reason, the aim of this research is to propose hybrid multiple attribute decision making approaches to effectively evaluate RP machines. In addition, because subjective considerations are relevant to selection decision, a fuzzy logic approach is adopted. The proposed selection procedure consists of several steps. First, we identify RP machines that the users consider. After constructing the evaluation criteria, we calculate the weights of the criteria by applying the fuzzy Analytic Hierarchy Process(AHP) method. Finally, we construct the fuzzy Technique of Order Preference by Similarity to Ideal Solution(TOPSIS) method to achieve the ranking order of all machines providing the decision information for the selection of RP machines.

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Cloning and Characterization of Liver cDNAs That Are Differentially Expressed between Chicken Hybrids and Their Parents

  • Sun, Dong-Xiao;Wang, Dong;Yu, Ying;Zhang, Yuan
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.12
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    • pp.1684-1690
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    • 2005
  • Using mRNA differential display technique, we investigated differential gene expression in hybrids relative to their parents in a diallel cross involving four chicken breeds in order to provide an insight into the molecular basis of heterosis in chicken. The results indicated that there was extensive differential gene expression between chicken F1 hybrids and their parents which was classified into four kinds of patterns as following: (1) bands only detected in hybrid F1; (2) bands only absent in hybrid F1; (3) bands only detected in parent P1 or P2; (4) bands absent in parent P1 or P2. Forty-two differentially expressed cDNAs were cloned and sequenced, and their expression patterns were confirmed by Reverse-Northern dot blot. Sequence analysis and database searches revealed that genes showed differential expression between hybrid and parents were regulatory and functional genes involved in metabolism, mRNA splicing, transcriptional regulation, cell cycles and protein modification. These results indicated that hybridization between two parents can cause changes in expression of a variety of genes. In conclusion, that the altered pattern of gene expression in hybrids may be responsible for heterosis in chickens.

Concept Analysis of Health Literacy for Patients with Cardiovascular Disease using Hybrid Model

  • Sim, Jeong Eun;Hwang, Seon Young
    • Research in Community and Public Health Nursing
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    • v.30 no.4
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    • pp.494-507
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    • 2019
  • Purpose: The purpose of this study is to provide a clear definition of the health literacy for patients with cardiovascular disease by analyzing the dimensions and properties using Hybrid concept analysis. Methods: The concept of health literacy of patients with cardiovascular disease was analyzed according to the cyclic process of theoretical phase-field work phase-final analysis phase presented in the Hybrid model. We reviewed 26 literatures and conducted in-depth interviews with 13 patients with cardiovascular disease. Results: The concept of health literacy in cardiovascular patients is derived from two dimensions and five attributes. Literacy skills, health information search ability and health information utilization skills were derived as attributes in the individual functional dimension, while active communication with the medical team and utilization of health information support resources were derived at the interrelational dimension. It is defined as the individualized and integrated ability of an individual to explore and utilize the various health information needed to make appropriate health decisions during the chronic course after diagnosis of cardiovascular disease, to communicate proactively with medical staffs and to utilize support resources. Conclusion: This study will contribute to the development and related research of health literacy measurement tools that can be used in cardiovascular nursing practice based on the attributes and indicators of health literacy for patients with cardiovascular disease.

Effects of the Surfactant and the Quaternary Ammonium Functional Groups on the Removal of Perrhenate Anions using Mesoporous Anion-Exchange Resins in Aqueous Solutions (암모늄 기능기와 계면활성제가 포함된 메조포러스 음이온교환수지를 이용한 수용액중 퍼리네이트(Perrhenate) 음이온 제거)

  • Lee, Byunghwan;Chung, Yeon-Sung;Park, Chulhwan
    • Korean Chemical Engineering Research
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    • v.46 no.2
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    • pp.436-442
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    • 2008
  • Organic-inorganic hybrid mesoporous anion-exchange resins were prepared for the adsorption of anions from aqueous solutions. The prepared samples were characterized using nitrogen adsorption-desorption measurements, Fourier transform infrared (FTIR) spectroscopy, and elemental analyses. Batch and kinetic experiments were performed to examine the anion-exchange performances of the prepared samples. Among the prepared samples, the hybrid mesoporous anion-exchange resins functionalized with tributylammonium groups showed higher adsorption capacities for perrhenate ions than did the resin functionalized with trimethylammonium groups. The surfactant, hexadecylamine, which had hydrophobic alkyl chains, also showed affinity for hydrophobic perrhenate anions.

High Efficiency AMOLED Using Hybrid of Small Molecule and Polymer Materials Patterned by Laser Transfer

  • Chin, Byung-Doo;Suh, Min-Chul;Kim, Mu-Hyun;Kang, Tae-Min;Yang, Nam-Choul;Song, Myung-Won;Lee, Seong-Taek;Kwon, Jang-Hyuk;Chung, Ho-Kyoon;Wolk, Martin B.;Bellmann, Erika;Baetzold, John P.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.163-166
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    • 2003
  • Laser-Induced Thermal Imaging (LITI) is a laser addressed patterning process and has unique advantages, such as high-resolution patterning with over-all position accuracy of the imaged stripes within 2.5 micrometer and scalability to large-size mother glass. This accuracy is accomplished using real-time error correction and a high -resolution stage control system that includes laser interferometers. Here the new concept of mixed hybrid system which complement the advantages of small molecular and polymeric materials for use as an OLED; our system can realize the easy processing of polymers and high luminance efficiency of recently developed small molecules. LITI process enables to pattern the stripes with excellent thickness uniformity and multi-stacking of various functional layers without using any type of fine metal shadow mask. In this study, we report a full-color hybrid OLED using the multi-layered structure of small molecular/polymeric species.

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Performance Enhancement of a DBS receiver using Hybrid Approaches in a Real-Time OS Environment (실시간처리 운영체계 환경에서 Hybrid 방식을 이용한 디지털 DBS 위성수신기 성능개선)

  • Seong, Yeong-Rak;Jung, Kyeong-Hoon;Kang, Dong-Wook;Kim, Ki-Doo;Kim, Sung-Hoon
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2005.11a
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    • pp.117-120
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    • 2005
  • A Digital Broadcasting Satellite (DBS) receiver converts digital A/V streams received from a satellite to analog NTSC A,/V signals in real-time. Multi-tasking is an efficient way to improve the utilization of the processor core in real-time applications. In this paper, we propose a hybrid approach with a balanced trade-off between hardware kernel and multi-tasking programming to increase a system throughput. First, the schedulability of the critical hard real-time tass in the DBS receiver is verified by using a simple feasibility test. Then. several soft real-time tasks are thoughtfully programmed to satisfy functional requirements of the system.

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