• Title/Summary/Keyword: Reverse function

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Current status on plant functional genomics (식물 유전자 연구의 최근 동향)

  • Cho, Yong-Gu;Woo, Hee-Jong;Yoon, Ung-Han;Kim, Hong-Sig;Woo, Sun-Hee
    • Journal of Plant Biotechnology
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    • v.37 no.2
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    • pp.115-124
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    • 2010
  • As the completion of genome sequencing, large collection of expression data and the great efforts in annotating plant genomes, the next challenge is to systematically assign functions to all predicted genes in the genome. Functional genome analysis of plants has entered the high-throughput stage. The generations and collections of mutants at the genome-wide level form technological platform of functional genomics. However, to identify the exact function of unknown genes it is necessary to understand each gene's role in the complex orchestration of all gene activities in the plant cell. Gene function analysis therefore necessitates the analysis of temporal and spatial gene expression patterns. The most conclusive information about changes in gene expression levels can be gained from analysis of the varying qualitative and quantitative changes of messenger RNAs, proteins and metabolites. New technologies have been developed to allow fast and highly parallel measurements of these constituents of the cell that make up gene activity. We have reviewed currently employed technologies to identify unknown functions of predicted genes including map-based cloning, insertional mutagenesis, reverse genetics, chemical mutagenesis, microarray analysis, FOX-hunting system, gene silencing mutagenesis, proteomics and chemical genomics. Recent improvements in technologies for functional genomics enable whole-genome functional analysis, and thus open new avenues for studies of the regulations and functions of unknown genes in plants.

Cloning and Characterization of ${\Delta}^1$-Pyrroline-5-Carboxylate Synthetase Genes and Identification of Point Mutants in Medicago truncatula

  • Song, Ki-Hoon;Song, Dae-Hae;Lee, Jeong-Ran;Kim, Goon-Bo;Choi, Hong-Kyu;Penmetsa, R. Varma;Nam, Young-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.52 no.4
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    • pp.458-468
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    • 2007
  • To tolerate environmentally adverse conditions such as cold, drought, and salinity, plants often synthesize and accumulate proline in cells as compatible osmolytes. ${\Delta}^1$-Pyrroline-5-carboxylate synthetase(P5CS) catalyzes the rate-limiting step of proline biosynthesis from glutamate. Two complete genes, MtP5CS1 and MtP5CS2, were isolated from the model legume Medicago truncatula by cDNA cloning and bacterial artificial chromosome library screening. Nucleotide sequence analysis showed that both genes consisted of 20 exons and 19 introns. Alignment of the predicted amino acid sequences revealed high similarities with P5CS proteins from other plant species. The two MtP5CS genes were expressed in response to high salt and low temperature treatments. Semi-quantitative reverse transcription-polymerase chain reaction showed that MtP5CS1 was expressed earlier than MtP5CS2, indicating differential regulation of the two genes. To evaluate the reverse genetic effects of nucleotide changes on MtP5CS function, a Targeting Induced Local Lesions in Genomes approach was taken. Three mutants each were isolated for MtP5CS1 and MtP5CS2, of which a P5CS2 nonsense mutant carrying a codon change from arginine to stop was expected to bring translation to premature termination. These provide a valuable genetic resource with which to determine the function of the P5CS genes in environmental stress responses of legume crops.

Impaired Hippocampal Synaptic Plasticity and Enhanced Excitatory Transmission in a Novel Animal Model of Autism Spectrum Disorders with Telomerase Reverse Transcriptase Overexpression

  • Rhee, Jeehae;Park, Kwanghoon;Kim, Ki Chan;Shin, Chan Young;Chung, ChiHye
    • Molecules and Cells
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    • v.41 no.5
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    • pp.486-494
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    • 2018
  • Recently, we have reported that animals with telomerase reverse transcriptase (TERT) overexpression exhibit reduced social interaction, decreased preference for novel social interaction and poor nest-building behaviors-symptoms that mirror those observed in human autism spectrum disorders (ASD). Overexpression of TERT also alters the excitatory/inhibitory (E/I) ratio in the medial prefrontal cortex. However, the effects of TERT overexpression on hippocampal-dependent learning and synaptic efficacy have not been investigated. In the present study, we employed electrophysiological approaches in combination with behavioral analysis to examine hippocampal function of TERT transgenic (TERT-tg) mice and FVB controls. We found that TERT overexpression results in enhanced hippocampal excitation with no changes in inhibition and significantly impairs long-term synaptic plasticity. Interestingly, the expression levels of phosphorylated CREB and phosphorylated $CaMKII{\alpha}$ were significantly decreased while the expression level of $CaMKII{\alpha}$ was slightly increased in the hippocampus of TERT-overexpressing mice. Our observations highlight the importance of TERT in normal synaptic function and behavior and provide additional information on a novel animal model of ASD associated with TERT overexpression.

Urbanization of Large Cities in Korea : Assessing Development Stages using Migration and Commuting data (한국 대도시의 도시화 특성 : 이동, 통근자 자료 분석을 통한 도시화 단계의 실증적 검토)

  • Kwon, Sang-Cheol
    • Journal of the Korean association of regional geographers
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    • v.17 no.5
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    • pp.536-553
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    • 2011
  • New urbanization different from the manufacturing based urban growth has been widely discussed in post-modern city, consumption city and others to reflect the urban changes in qualitative manner. Urbanization stage models consider large cities to be in mature stage, reurbanization and the stages are assumed to be experienced successively in lower sized cities. However, since the industrial restructuring implies new urbanization experiences, this study examines new urbanization in diverse aspects such as the population change and the geographic and social characteristics of commuters and migrants for the 6 large cities in Korea. Seoul follows the urbanization stages in order while other 5 large cities are divergent in their transition from the industrial city. Regional large cities reveal broad reverse commuting and selective in-migration of economically active households for better work and housing opportunities available in central cities. Similar to the consumption city thesis with enhanced cultural and recreational amenities in western cities, the widening urban residential function including housing and other services is a new urbanization characteristic of large cities in Korea.

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Fault Detection through the LASAR Component modeling of PLD Devices (PLD 소자의 LASAR 부품 모델링을 통한 고장 검출)

  • Pyo, Dae-in;Hong, Seung-beom
    • Journal of Advanced Navigation Technology
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    • v.24 no.4
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    • pp.314-321
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    • 2020
  • Logic automated stimulus and response (LASAR) software is an automatic test program development tool for logic function test and fault detection of avionics components digital circuit cards. LASAR software needs to the information for the logic circuit function and input and output of the device. If there is no component information, normal component modeling is impossible. In this paper, component modeling is carried out through reverse design of programmable logic device (PLD) device without element information. The developed LASAR program identified failure detection rates through fault simulation results and single-seated fault insertion methods. Fault detection rates have risen by 3% to 91% for existing limited modeling and 94% for modeling through the reverse design. Also, the 22 case of stuck fault with the I/O pin of EP310 PLD were detected 100% to confirm the good performance.

A Proposal of Output Method of Round Window Stimulation Type Middle Ear Implants using Acoustic Transmission (공기 전도형 출력을 갖는 정원창 자극형 인공중이의 출력방식 제안)

  • Seong, Kiwoong;Lee, KyuYup;Kim, Myoung Nam;Cho, Jin-Ho
    • Journal of Korea Multimedia Society
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    • v.21 no.6
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    • pp.678-684
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    • 2018
  • In order to broaden the indication of middle ear implant, research has been actively conducted on the reverse output method that stimulates the round window. However, it is very difficult to transmit the vibration output effectively because the indivisual anatomical difference of the round window niche is very large and also the visual field is not secured even by a skilled otolaryngologic surgeon. In this paper, we propose a new reverse stimulation method of middle ear implants that transmits energy to the inner ear by using air as a medium. This can compensate for the disadvantages of the conventional method of transmitting vibration energy and minimizes the energy transfer efficiency interference due to the combination of the excitation point and the output device. It was shown that forward and backward transfer characteristics were obtained by cadaveric experiments, and it was shown that it can overcome the acoustical impedance of high round window and transmit energy to inner ear. The receiver, which is the output device of the conventional hearing aids, can generate a constant volume velocity, so it can have a high output at a limited volume, such as a round window niche. So, suggested method can overcome the high acoustical impedance of the round window and deliver acoustic energy to the inner ear.

Passive UHF RFID Propagation Characteristics and Reconsideration of Link budget on Practical Communication Area (수동형 UHF RFID 인터페이스에 대한 Link budget의 재해석 및 전파 환경 요소 분석)

  • Jung, Jin-Woo;Park, Kyoung-Tae;Roh, Hyoung-Hwan;Park, Jun-Seok;Kim, Hyeong-Seok
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.469-472
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    • 2008
  • In this paper, we discuss the recent trends on the passive UHF RFID tag chip design techniques and several important system parameters. We also summarize link budget studies on both conventional and modem UHF RFID communications. The paper highlights the reverse link limited case, which has known to be the minor concern if reader continuous wave (CW) can reach the tag in sufficient level. This makes sense when the tag sensitivity is rather high (over 10-12${\mu}W$); however, since the tag chip fabrication technologies have been developed by time, the tag chip threshold levels are now less-dominant in determining link margin. If the tag limitation can be alleviated, the forward link limited case can be resolved; thus, we rather focus on the path-loss problem. Since the path-losses are still exist in both forward and reverse links, and it can be doubled while CW travels the reader-tag-reader path because forward link and reverse link are on the same distance. Consider if reader receiver sensitivity is very high in the worst case. In this case, weaken tag response (i.e., backscatters) cannot reach the level that reader receiver can process tag data; bit-error rate can be higher. Overall, backscatter levels should be high enough so that reader receiver can correctly function. After discussing link budget, we carried out practical measurements on fading effects between two circularly polarized UHF RFID antennas in a small scale area.

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Restoration of Membrane Performance for Damaged Reverse Osmosis Membranes through in-situ Healing (손상된 역삼투막의 in-situ 힐링을 통한 막 성능 복원)

  • Yun, Won Seob;Rhim, Ji Won;Cho, Young Ju
    • Membrane Journal
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    • v.29 no.2
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    • pp.96-104
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    • 2019
  • The purpose of this paper is whether or not the in-situ restoration of the reverse osmosis (RO) membranes which its membrane function is lost is possible. The damaged RO membranes are double coated through the salting-out method by the poly(styrene sulfonic acid) sodium salt as the cationic exchange polymer and the polyethyleneimine as the anionic exchange polymer and also conducted the opposite order of the coating materials. And according to the concentration, time and ionic strength, the flux and rejection are measured for the coated membranes. Then the best coating condition is to apply for the RO membrane module of the household water purifier to know the possibility of the in-situ restoration for the commercial module. When the condition of the PEI 30,000 ppm (IS = 0.1)/PSSA 20,000 ppm (IS = 0.7) is applied, the rejection was enhance from 69% for the damaged module to 86% (90% for the pristine module).

Study on the comparison result of Machine code Program (실행코드 비교 감정에서 주변장치 분석의 유효성)

  • Kim, Do-Hyeun;Lee, Kyu-Tae
    • Journal of Software Assessment and Valuation
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    • v.16 no.1
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    • pp.37-44
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    • 2020
  • The similarity of the software is extracted by the verification of comparing with the source code. The source code is the intellectual copyright of the developer written in the programming language. And the source code written in text format contains the contents of the developer's expertise and ideas. The verification for judging the illegal use of software copyright is performed by comparing the structure and contents of files with the source code of the original and the illegal copy. However, there is hard to do the one-to-one comparison in practice. Cause the suspected source code do not submitted Intentionally or unconsciously. It is now increasing practically. In this case, the comparative evaluation with execution code should be performed, and indirect methods such as reverse assembling method, reverse engineering technique, and sequence analysis of function execution are applied. In this paper, we analyzed the effectiveness of indirect comparison results by practical evaluation . It also proposes a method to utilize to the system and executable code files as a verification results.

Evaluation of Reverse Electrodialysis based on the Number of Cell Pairs and Stack Size Using Patterned Ion Exchange Membrane (패턴형 이온교환막을 이용한 스택의 셀 수 및 크기에 따른 역전기투석 성능 평가)

  • Dong-Gun Lee;Hanki Kim;Namjo Jeong;Young Sun Mok;Jiyeon Choi
    • New & Renewable Energy
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    • v.19 no.2
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    • pp.31-39
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    • 2023
  • Salinity gradient energy can be generated from a mixture of water streams with different salt concentrations by using reverse electrodialysis (RED). In this study, we evaluated the effect of stack size and number of cell pairs on the energy efficiency and specific energy of the RED process. Additionally, we studied the prementioned parameters to maximize the power density of RED. The performance of the RED stack which used a patterned ion exchange membrane, was evaluated as a function of stack size and feed flow rate. Moreover, it was noted that an increase in stack size increased the ion movement through the ion exchange membrane. Furthermore, an increase in feed flow rate led to a reduction in the concentration variation, resulting in an increase in OCV and power density. The energy efficiency and specific energy for 100 cells in the 10 × 10 cm2 stack were the highest at 12% and 0.05 kWh/m3, respectively, while the power density from 0.33 cm/s to 5 × 5 cm2 stack was the highest at 0.53 W/m2. The study showed that the RED performance can be improved by altering the size of the stack and the number of cell pairs, thereby positively affecting energy efficiency and specific energy.