• IMMUNE NETWORK
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• 제20권1호
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• pp.2.1-2.19
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• 2020

Acute viral infection or vaccination generates highly functional memory CD8 T cells following the Ag resolution. In contrast, persistent antigenic stimulation in chronic viral infection and cancer leads to a state of T-cell dysfunction termed T-cell exhaustion. We and other have recently identified a novel subset of exhausted CD8 T cells that act as stem cells for maintaining virus-specific CD8 T cells in a mouse model of chronic lymphocytic choriomeningitis virus infection. This stem cell-like CD8 T-cell subset has been also observed in both mouse and human tumor models. Most importantly, in both chronic viral infection and tumor models, the proliferative burst of Ag-specific CD8 T cells driven by PD-1-directed immunotherapy comes exclusively from this stem cell-like CD8 T-cell subset. Therefore, a better understanding of the mechanisms how CD8 T-cell subsets are regulated during chronic viral infection and cancer is required to improve the current immunotherapies that restore the function of exhausted CD8 T cells. In this review, we discuss the differentiation of virus-specific CD8 T cells during chronic viral infection, the characteristics and function of CD8 T-cell subsets, and the therapeutic intervention of PD-1-directed immunotherapy in cancer.

• 품질경영학회지
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• 제29권2호
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• pp.37-45
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• 2001

A survival variable is a non-negative random variable X with distribution function F(t) satisfying F(0) : 0 and a survival function F(t): 1-F(t). This variable is said to be New Better than Used of specified age t$_{0}$ if F(x+ t$_{0}$)$\leq$F(x).F(t$_{0}$) for all x$\geq$0 and a fixed t$_{0}$. We propose the test for H$_{0}$ : F(x+t$_{0}$)=F(x).F(t$_{0}$) for all x$\geq$0 against H$_1$: F(x+t$_{0}$) $\leq$ F(x).F(t$_{0}$) for all x$\geq$0 when the specified age to is unknown but can be estimated from the data when t$_{0}$=ζ$_{p}$, the pth percentile of F. This test statistic, which is based on the normalized spacings between the ordered observations, is readily applied in the case of small sample. Also, our test is more simple than Ahmad's test (1998). Finally, the performance of our test is presented.our test is presented.

• Tuberculosis and Respiratory Diseases
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• 제86권4호
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• pp.304-318
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• 2023

Background: Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment and significantly contribute to immune evasion. We investigated the effects of CAFs on the immune function of CD4+ and CD8+ T cells in non-small cell lung cancer (NSCLC). Methods: We isolated CAFs and normal fibroblasts (NFs) from tumors and normal lung tissues of NSCLC patients, respectively. CAFs were co-cultured with activated T cells to evaluate their immune regulatory function. We investigated the effect of CAF conditioned medium (CAF-CM) on the cytotoxicity of T cells. CAFs were also co-cultured with activated peripheral blood mononuclear cells and further incubated with cyclooxygenase-2 (COX2) inhibitors to investigate the potential role of COX2 in immune evasion. Results: CAFs and NFs were isolated from the lung tissues (n=8) and lymph nodes (n=3) of NSCLC patients. Immune suppressive markers, such as COX2 and programmed death-ligand 1 (PD-L1), were increased in CAFs after co-culture with activated T cells. Interestingly, CAFs promoted the expression of programmed death-1 in CD4+ and CD8+ T cells, and strongly inhibited T cell proliferation in allogenic and autologous pairs of CAFs and T cells. CAF-CM decreased the cytotoxicity of T cells. COX2 inhibitors partially restored the proliferation of CD4+ and CD8+ T cells, and downregulated the expression of COX2, prostaglandin E synthase, prostaglandin E2, and PD-L1 in CAFs. Conclusion: CAFs promote immune evasion by suppressing the function of CD4+ and CD8+ T cells via their effects on COX2 and PD-L1 in NSCLC. The immunosuppressive function of CAFs could be alleviated by COX2 inhibitors.

• 충청수학회지
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• 제28권2호
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• pp.331-343
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• 2015

Invertible transformations over n-bit words are essential ingredients in many cryptographic constructions. When n is large such invertible transformations are usually represented as a composition of simpler operations such as linear functions, S-P networks, Feistel structures and T-functions. Among them we study T-functions which are probably invertible transformations and are very useful in stream ciphers. In this paper we study the number of single cycle T-functions satisfying some conditions and characterize single cycle T-functions on $(\mathbb{Z}_2)^n$ generated by some elements in $(\mathbb{Z}_2)^{n-1}$.

• 대한수학회논문집
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• 제16권4호
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• pp.621-626
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• 2001

Let { $A_{>o}$ t= exp(M log t)} $_{t}$ be a dilation group where M is a real n$\times$n matrix whose eigenvalues has strictly positive real part, and let $\rho$be an $A_{t}$ -homogeneous distance function defined on ( $R^{n}$ ). Suppose that K is a function defined on ( $R^{n}$ ) such that /K(x)/$\leq$ (No Abstract.see full/text) for a decreasing function defined on (t) on R+ satisfying where wo(x)=│log│log (x)ll. For f$\in$ $L_{1}$ ( $R^{n}$ ), define f(x)=sup t>0 Kt*f(x)=t-v K(Al/tx) and v is the trace of M. Then we show that \ulcorner is a bounded operator of $L_{-{1}( $R^{n}$ ) into $L^1$,$\infty$( $R^{n}$).

• Kyungpook Mathematical Journal
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• 제59권1호
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• pp.65-71
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• 2019

This paper is concerned with the existence of positive solutions of the nonlinear Neumann boundary value problems $$\{u^{{\prime}{\prime}}+a(t)u={\lambda}b(t)f(u),\;t{\in}(0,1),\\u^{\prime}(0)=u^{\prime}(1)=0$$, where $a,b{\in}C[0,1]$ with $a(t)>0,\;b(t){\geq}0$ and the Green's function of the linear problem $$\{u^{{\prime}{\prime}}+a(t)u=0,\;t{\in}(0,1),\\u^{\prime}(0)=u^{\prime}(1)=0$$ may change its sign on $[0,1]{\times}[0,1]$. Our analysis relies on the Leray-Schauder fixed point theorem.

• 한국정보통신학회논문지
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• 제24권1호
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• pp.138-140
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• 2020

As the IoT is applied to home and industrial networks, data generated by the IoT is being processed at the cloud edge. Intrusion detection function is very important because it can be operated by invading IoT devices through the cloud edge. Data delivered to the edge network in the cloud environment is traffic at the application layer. In order to determine the intrusion of the packet transmitted to the IoT, the intrusion should be detected at the application layer. This paper proposes the intrusion detection function at the application layer excluding normal traffic from IoT intrusion detection function. As the proposed method, we obtained the intrusion detection result by decision tree method and explained the detection result for each feature.

• 기본간호학회지
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• 제6권3호
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• pp.507-521
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• 1999

Yu-Dong-Kong exercise is to produce heat from rubbing hands and is composed of 10 different types of exercise using warmed hands. The objective of this research is to evaluate the effect of Yu-Dong-Kong exercise on physical function and emotional state in elderly. The design of research is Nonequivalent Control Group Pretest-Posttest Design. The independent variable is Yu-Dong-Kong exercise, and the dependent variables are physical function and emotional state. Subjects are 18 elderly in the experimental group and 16 elderly in control group. All of them are above 60 year old and live in 1-city, Kyonggi-do. The exercise period was 4 weeks and data were collected from April to August in 1998. The exercise frequency was once a day. The exercise duration was from 10 to 20 minutes. The measurement tools are modified 1) Cornell Medical Index-Health questionnaire and 2) Geriatric Depression Scale. Collected data were analyzed by t-test and paired t-test based on the purposes of research using SPSS-Window package. The results are summarized as follows : 1. There was no difference in pre-exercise physical function between two groups (t=-.95, p=.35). 2. The hypothesis that 'physical function in the experimental group will be improved compared to the control group' was not supported by t-test(t=-.925, p=.362). However. the physical function in the experimental group showed much improvement than that in the control group. 3. The hypothesis that 'emotional state in the experimental group will be improved compared to the control group' was not supported by t-test(t=-1.715, p=.096). However, the emotional state in the experimental group showed much improvement than that in the control group. 4. The hypothesis that 'physical function will be improved in the post-exercise compared to pre-exercise' was not supported by paired t-test(t=.302, p=.766) However, a slight improvement in the physical function was found. For the further study, it is recommended to reevaluate the effect of Yu-Dong-Kong exercise through large number of subjects and long-term study. Also, a separate study with different type of subjects is recommended. In addition, continuation and compliance this strategy for exercise should be developed.

• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.1013-1017
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• 2003

A thermophilic nonspore-forming rod isolated from hay compost in Korea was subjected to a taxonomic study. The microorganism, designated as $SC-1^T$, was identified as a nitrate-reducing and nonmotile bacterium. Although the strain was negatively Gram-stained, a KOH test showed that the strain $SC-1^T$ belonged to a Gram-positive species. Growth was observed between 45 and $70^{\circ}C$. The optimal growth temperature and pH were $60^{\circ}C$ and pH 7.5, respectively. The G+C content of the genomic DNA was 65 mol% and the major quinone types were MK-6 and MK-7. A phylogenetic analysis based on 16S rDNA sequences revealed that the strain $SC-1^T$ was most closely related to Symbiobacterium thermophilum. However, the level of DNA-DNA relatedness between strain $SC-1^T$ and the type strain for Symbiobacterium thermophilum was approximately 30%. Accordingly, on the basis of the phenotypic traits and molecular systematic data, the strain $SC-1^T$ would appear to represent a new species within the genus Symbiobacterium. The type strain for the new species is named $SC-1^T$ ($=KCTC\;0307BP^T;\;DSM15906^T$).

• 한국융합학회논문지
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• 제12권11호
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• pp.457-466
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• 2021

본 연구는 갱년기 여성들에게 취약하다고 알려진 기억력과 주의집중력, 언어기능을 증진시키기 위해 개발된 모바일 앱 기반 인지훈련 프로그램의 효과를 규명하고자 하였다. 기억력 저하를 호소하는 만 40세에서 60세 사이의 갱년기 여성 40명을 대상으로 실시하였다. 모바일 앱 기반의 인지훈련은 8주간의 프로그램으로 회기당 20~30분, 3회/주 수행하여 총 24회기였다. 조사는 기초조사를 포함한 사전조사와 사후조사로 진행되었다. 연구변수는 객관적 인지기능(전반적 인지기능, 기억력, 주의집중력, 언어기능)과 주관적 인지기능, 삶의 질이었다. 연구결과 전반적 인지기능(t=-8.688, p<.001)과 기억력(t=-4.765, p<.001), 주의집중력 정반응수(t=-7.293, p<.001), 언어기능 중 고빈도 단어에 대한 정반응수(Z=-2.179, p=.036), 저빈도 단어에 대한 정반응수(Z=-2.737, p=.009), 삶의 질(t=-3.358, p=.002)은 모두 통계적으로 유의하였으나 주관적 인지기능은 통계적으로 유의한 차이가 없는 것으로 나타났다. 기능성 앱을 통해 제공되었된 인지훈련 프로그램은 인지기능을 향상시키는데 도움을 주었으며 전문가의 개입 없이도 가정에서 접근하기 쉬운 인지 중재도구로 활용될 수 있을 것이다.