• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.254-258
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• 2005

We have conducted in vitro reconstitution study of ferritin from its subunits FerH and FerL. For the reconstitution, FerH was produced from an expression vector construct in Escherichia coli and was purified from a heat treated cell extract by using one-step column chromatography. FerL was expressed as inclusion bodies. The denatured form of FerL was obtained by a simple washing step of the inclusion bodies with 3 M urea. The reconstitution experiment was conducted with various molar ratios of urea-denatured FerH and FerL to make the ferritin nanoparticle with a controlled composition of FerH and FerL. SDS-PAGE analysis of the reconstituted ferritins revealed that the reconstitution required the presence of more than 40 molar$\%$ of FerH in the reconstitution mixture. The assembly of the subunits into the ferritin nanoparticle was confmned by the presence of spherical particles with diameter of 10 nm by the atomic force microscopic image. Further analysis of the particles by using a transmission electron microscope revealed that the reconstituted particles exhibited different percentages of population with dense iron core. The reconstituted ferritin nanoparticles made with molar ratios of [FerH]/[FerL]=l00/0 and 60/40 showed that 80 to $90\%$ of the particles were apoferritin, devoid of iron core. On the contrary, all the particles formed with [FerH]/[FerL]=85/ 15 were found to contain the iron core. This suggests that although FerH can uptake iron, a minor portion of FerL, not exceeding $40\%$ at most, is required to deposit iron inside the particle.

• Molecules and Cells
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• v.20 no.2
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• pp.256-262
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• 2005

The neuronal cytoskeleton is essential for establishment of neuronal polarity, but mechanisms controlling generation of polarity in the cytoskeleton are poorly understood. The nonreceptor tyrosine kinase, Fer, has been shown to bind to microtubules and to interact with several actin-regulatory proteins. Furthermore, Fer binds p120 catenin and has been shown to regulate cadherin function by modulating cadherin-${\beta}$-catenin interaction. Here we show involvement of Fer in neuronal polarization and neurite development. Fer is concentrated in growth cones together with cadherin, ${\beta}$-catenin, and cortactin in stage 2 hippocampal neurons. Inhibition of Fer-p120 catenin interaction with a cell-permeable inhibitory peptide (FerP) increases neurite branching. In addition, the peptide significantly delays conversion of one of several dendrites into an axon in early stage hippocampal neurons. FerP-treated growth cones also exhibit modified localization of the microtubule and actin cytoskeleton. Together, this indicates that the Fer-p120 interaction is required for normal neuronal polarization and neurite development.

• Korean Chemical Engineering Research
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• v.55 no.4
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• pp.473-477
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• 2017

The polymer membrane of proton exchange membrane fuel cell (PEMFC) has a great influence on PEMFC performance and durability. In this study, hydrogen permeability, fluorine emission rate (FER), lifetime, and performance of Nafion membranes with different thicknesses were measured to investigate the effect of thickness of polymer membrane on performance and durability. The relationship between membrane thickness and lifetime was obtained from the relationships between hydrogen permeability and membrane thickness, hydrogen permeability and FER, FER and lifetime. As the membrane became thicker, the hydrogen permeability and FER decreased and the lifetime increased. On the other hand, the performance decreased with increasing membrane resistance. The membrane thickness range satisfying both performance and durability was 25 to $28{\mu}m$.

• Polymer(Korea)
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• v.27 no.3
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• pp.176-182
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• 2003

The fluorine-containing epoxy resin, 2-trifluorotoluene diglycidylether (FER) was prepared by reaction of 2-chloro-${\alpha}$,${\alpha}$,${\alpha}$-trifluorotoluene with glycerol diglycidylether in the presence of pyridine catalyst. Curing behavior of FER/DDM system was investigated using dynamic and isothermal DSC. Cure activation energy (Ea) was determined by Flynn-Wall-Ozawa's equation. The rheological properties of FER/DDM system were studied under isothermal condition using a rheometer. Cross-linking activation energy (Ec) was determined from the Arrhenius equation based on gel time and curing temperature. As a result, the chemical structure of FER was confirmed by FT-IR, $\^$13/C NMR, and $\^$19/F NMR spectroscopy. The cure activation energy of FER/DDM system was 55.4 kJ/mol and conversion and conversion rate were increased with the curing temperature. The cross-linking activation energy of FER/DDM system was 41.6 kJ/mol and gel time was decreased with the curing temperature.

• Bulletin of the Korean Mathematical Society
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• v.55 no.1
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• pp.187-204
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• 2018

Let $R={\bigoplus}_{{\alpha}{\in}{\Gamma}}\;R_{\alpha}$ be a graded integral domain, H be the set of nonzero homogeneous elements of R, and ${\star}$ be a semistar operation on R. The purpose of this paper is to study the properties of $quasi-Pr{\ddot{u}}fer$ and UMt-domains of graded integral domains. For this reason we study the graded analogue of ${\star}-quasi-Pr{\ddot{u}}fer$ domains called $gr-{\star}-quasi-Pr{\ddot{u}}fer$ domains. We study several ring-theoretic properties of $gr-{\star}-quasi-Pr{\ddot{u}}fer$ domains. As an application we give new characterizations of UMt-domains. In particular it is shown that R is a $gr-t-quasi-Pr{\ddot{u}}fer$ domain if and only if R is a UMt-domain if and only if RP is a $quasi-Pr{\ddot{u}}fer$ domain for each homogeneous maximal t-ideal P of R. We also show that R is a UMt-domain if and only if H is a t-splitting set in R[X] if and only if each prime t-ideal Q in R[X] such that $Q{\cap}H ={\emptyset}$ is a maximal t-ideal.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.123-126
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• 2011

As the number of users of smart phone and smart pad are increasing, the deployment of WiFi APs has been accelerated. Also Internet local broadcasting service will be activated near future. But transmission error is the critical problem, due to the one-way transmission of the data to the receivers. In this paper, FER is analysed according to BER and frame length, and repetitive transmission technique is proposed to reduce the effective FER.

• Bulletin of the Korean Mathematical Society
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• v.56 no.6
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• pp.1485-1495
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• 2019

The purpose of this paper is to compute the number of semistar operations of certain classes of finite dimensional $Pr{\ddot{u}}fer$ domains. We prove that ${\mid}SStar(R){\mid}={\mid}Star(R){\mid}+{\mid}Spec(R){\mid}+ {\mid}Idem(R){\mid}$ where Idem(R) is the set of all nonzero idempotent prime ideals of R if and only if R is a $Pr{\ddot{u}}fer$ domain with Y -graph spectrum, that is, R is a $Pr{\ddot{u}}fer$ domain with exactly two maximal ideals M and N and $Spec(R)=\{(0){\varsubsetneq}P_1{\varsubsetneq}{\cdots}{\varsubsetneq}P_{n-1}{\varsubsetneq}M,N{\mid}P_{n-1}{\varsubsetneq}N\}$. We also characterize non-local $Pr{\ddot{u}}fer$ domains R such that ${\mid}SStar(R){\mid}=7$, respectively ${\mid}SStar(R){\mid}=14$.

• Annual Conference on Human and Language Technology
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• 1995.10a
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• pp.195-207
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• 1995

일본어는 한자, 히라가나, 가다가나 등 다양한 종류의 문자를 사용하며 이들의 혼용 비율이 매우 높아 띄어쓰기를 하지 않아도 문서의 가독성을 유지한다. ICOT 사전, EDR 사전, ATLAS I/JK사전 등 기존의 전자 사전에서 복합 자종의 표제어가 차지하는 비율(한자+히라가나의 표제어 제외)은 평균 8.8%로 그 수가 매우 작다. 따라서, 문장 내에서 자종의 변화는 단어를 구분하는 하나의 delimiter로 이용될 수 있다. 본 시스템에서는 형태소 분석의 전단계로 전처리기를 두어 자종정보(character type information)에 의한 fragment 분리 및 예외 단어, 정형표현 처리를 수행하며 각 fragment 의 형태소 분석 방법을 제시한다. 형태소 분석기는 전처리기의 처리 결과를 입력받아 각각의 fragment를 전처리기가 제시한 분석 방법에 따라 분석하여 입력 문장의 가능한 모든 분석을 추출한다. 이 방법은 불필요한 사전 탐색과 접속 체크 회수를 줄여 분석 성능을 향상시킨다.

• Korean Journal of Veterinary Service
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• v.35 no.4
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• pp.307-312
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• 2012

Iron deficiency anemia is also recognized as a serious disorder in many livestock, especially, piglets. We previously studied that the iron-fortified yeast (Saccharomyces cerevisiae) producing Sus scrofa ferritin heavy-chain (FER) was bioavailable to mice with iron deficiency. In this study, we determined whether FER could improve iron deficiency in piglets. The bioavailability of FER was examined by measuring body weight gain, hemoglobin concentration and hematocrit value in suckling and weaning piglets. We found that FER significantly increased hemoglobin value and the hematocrit ratio in suckling piglets (P<0.05). Furthermore, FER treatment significantly enhanced body weight gain in both groups of the suckling and weaning piglets (P<0.05). These results suggest that the iron-fortified recombinant yeast strain is helpful in iron absorption in piglets.

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.25-33
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• 2023

The purpose of this study is to evaluate the impact of intermediate features on FER performance. To achieve this objective, intermediate features were extracted from the input images at specific layers (FM1~FM4) of the pre-trained network (Resnet-18). These extracted intermediate features and original images were used as inputs to the vision transformer (ViT), and the FER performance was compared. As a result, when using a single image as input, using intermediate features extracted from FM2 yielded the best performance (training accuracy: 94.35%, testing accuracy: 75.51%). When using the original image as input, the training accuracy was 91.32% and the testing accuracy was 74.68%. However, when combining the original image with intermediate features as input, the best FER performance was achieved by combining the original image with FM2, FM3, and FM4 (training accuracy: 97.88%, testing accuracy: 79.21%). These results imply that incorporating intermediate features alongside the original image can lead to superior performance. The findings can be referenced and utilized when designing the preprocessing stages of a deep learning model in FER. By considering the effectiveness of using intermediate features, practitioners can make informed decisions to enhance the performance of FER systems.