• Tuberculosis and Respiratory Diseases
• /
• v.41 no.2
• /
• pp.135-143
• /
• 1994

Background: The cell mediated immunity has an important role in the pathogenesis of tuberculosis. sIL-2R has been known as a sensitive marker of T lymphocyte activation Elevated serum levels of sIL-2R have been found in patients with lymphoproliferative disorders, organ transplantation, autoimmune diseases, and various granulomatous diseases. Elevated levels of sIL-2R have been also found in the serum and pleural fluid of the patients with tuberculosis. To evaluate the diagnostic value of sIL-2R in the differentiation of tuberculous pleurisy and nontuberculous pleurisy. We measured the level of sIL-2R in the sera and pleural fluids of 12 patients with tuberculous pleurisy and 32 patients with nontuberculous pleurisy. Method: Samples of pleural fluid and serum were centrifuged at 2500 rpm for 10 min to remove cell pellets. Soluble IL-2R was measured with a sandwitch enzyme immunoassay using the Cellfree(r) Interleukin-2 Receptor Test kit(T-cell science,Inc. Cambridge, MA). Results: The results obtained were as follows: 1) The sIL-2R level in pleural fluid of the patients with tuberculous pleurisy was higher than that of patients with nontuberculous pleurisy(P<0.005). 2) When the sIL-2R level above 5,000 u/ml in pleural fluid was used as the cut-off value to diagnose tuberculous pleurisy, it had a sensitivity of 84.6% and a specificity of 90.9%. 3) The sIL-2R level in the sera of the patients with tuberculous pleurisy was higher than that of patients with bacterial pleural effusions and normal control group(P<0.05) and there was no difference of levels compared with malignant pleural effusions and transudative pleural effusions(P>0.05). 4) In patients with tuberculous pleurisy, the mean concentration of sIL-2R in pleural fluid was higher than that in serum(P<0.005). Conclusion: These findings suggest that the measurement of elevated levels of pleural fluid sIL-2R in tuberculous pleurisy may be useful in the differential diagnosis between patients with tuberculous pleurisy and nontuberculous pleurisy.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.4
• /
• pp.2429-2432
• /
• 2013

Background and Objectives: Yanting in Sichuan Province is one of the highest risk areas of esophageal cancer (EC) in the world. We here summarize the epidemiology of EC in Yanting using data from the national screening programme during 2006-2011. Methods: Random cluster sampling was used to select a proportion of natural villages from six towns in Yanting, and residents aged 40-69 years old were invited for screening. Participants were screened using endoscopy with iodine staining and then confirmed by histological examinations. Results: The overall detection rates of low-grade hyperplasia (LH), moderate hyperplasia (MH), high-grade hyperplasia (HH), carcinoma in situ (CIS), intramucosal carcinoma (IC) and invasive carcinoma (INC) were 5.33%, 1.28%, 0.68%, 0.15%, 0.06% and 0.29%, respectively. The detection rates of LH, MH, HH and INC increased with age, reaching the peak among those aged 60-65 years, and the prevalences of LH and MH were higher among men than among women. In addition, the detection rates of hyperplasia were much higher in mountainous than in hilly areas. Conclusions: Among the high risk population, there are a great number of people with early-stage EC or precancerous conditions who do not have presenting symptoms. In particular, the elderly, men, or those living in mountainous areas are the most vulnerable population. It is therefore important to reinforce health education and screening services among such high risk populations.

• The Journal of the Acoustical Society of Korea
• /
• v.24 no.7
• /
• pp.423-430
• /
• 2005

In this paper. a microphone array beamforming algorithm that reduces the signal distortion caused by reverberation and near-field effect in car environment is proposed. When reverberation or near-field effect is present, an optimum beamformer should be constructed with a steering vector consisting of transfer functions between source and microphones, but it is generally difficult to estimate transfer functions on-line without knowledge of the source signal. Instead, a sub-optimal beamforming algorithm that reduces signal distortion is proposed. It is constructed with steering vectors consisting of relative transfer functions between reference sensor and other sensors. In order to evaluate the performance of the proposed algorithm. we had recorded noisy speech database in a car, and performed speech recognition experiments with HMM Toolkit (HTK) released by Cambridge University. The recognition rate of the proposed algorithm was 15 percents higher than that of the conventional far-field beamformers in best case.

• Journal of Microbiology
• /
• v.40 no.1
• /
• pp.11-19
• /
• 2002

Mice immunized with equine herpesvirus type-1(EHV-1) L-particles skewed a significant increase (p<7.75) in serum antibody titers. Upon a booster dose four weeks lateral antibody titers increased significantly. Interestingly, immunization via intravenous or intramuscular route induced significantly higher (p<0.75) antibody titers. However, mice iummunized with UV-treated L-particles, visions or immunization via intranasal route induced lower antibody titers. Upon challenge inoculation with wildtype EHV-1, our data showed there was a poor correlation between antibody titers and protection against virus replication. Therefore, the role of cell-mediated immunity Inwards protection was investigated. As predicted, the strongest cell-mediated immunity, as measured by delayed-hypersensitivity test, was detected in mice immunized with live virus particles. The magnitude of cell-mediated immune response correlated with the efficacy of L-particles as immunizing agent. The highest efficacy, as indicated in mice immunized via intranasal routed was highly correlated with cell-mediated immunity. A similar phenomenon was also demonstrated in mice immunized intranasally with UV-treated L-particles. However, the degree of protection was reduced when mice immunized intravenously or intramuscularly with UV-treated L-particles. In conclusion, protection conferred in these animals was highly implicated by immune cells and the least by antibodies. The route of immunization and the nature of the antigen also contributed to the efficacy of L-particles as immunizing agent. In contrast to that of herpes simplex virus type 1, our data showed EHV-1 non-infectious L-particles are highly suitable for immunization of the host against EHV-1 disease.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.9B
• /
• pp.822-831
• /
• 2008

This paper examines the theoretical and empirical technology diffusion processes to understand the Korean success in the internet access service markets. In order to do this, first, we propose an integrated demand diffusion model in terms of competition of inter-and intra-technologies and market structure as represented by the number of operators in the market. Second, by using the proposed model, we analyze the dynamic diffusion processes of Korean internet access services such as Narrow-band technology including Dial modem vs. Broad-band technology including ISDN, xDSL and Cable modem. The competition of inter-and intra-technologies as well as the extent of market competition has made a positive effect on the diffusion patterns of internet access demand. And also we propose, based on the proposed model and its empirical results, several implications for diffusion strategies and policies in the future of ICT market in Korea.

• Korean Journal of Logic
• /
• v.15 no.1
• /
• pp.155-190
• /
• 2012

As far as Hilbert's Program is concerned, there seems to be important differences in the development of Wittgenstein's thoughts. Wittgenstein's main claims on this theme in his middle period writings, such as Wittgenstein and the Vienna Circle, Philosophical Remarks and Philosophical Grammar seem to be different from the later writings such as Wittgenstein's Lectures on the Foundations of Mathematics (Cambridge 1939) and Remarks on the Foundations of Mathematics. To show that differences, I will first briefly survey Hilbert's program and his philosophy of mathematics, that is to say, formalism. Next, I will illuminate in what respects Wittgenstein was influenced by and criticized Hilbert's formalism. Surprisingly enough, Wittgenstein claims in his middle period that there is neither metamathematics nor proof of consistency. But later, he withdraws his such radical claims. Furthermore, we cannot find out any evidences, I think, that he maintained his formerly claims. I will illuminate why Wittgenstein does not raise such claims any more.

• STI Policy Review
• /
• v.5 no.1
• /
• pp.1-33
• /
• 2014

Despite a commonly held belief that standards obstruct innovation, recent research shows that they can actually play critical roles in supporting various activities of technological innovation. Thus, providing an innovation-friendly environment through standardization has been gaining much attention in recent years; however, there is as yet limited understanding, due to complex dynamics and high uncertainties associated with innovation, as well as a variety of different types and functions of standards with various stakeholders involved. The problem becomes even more challenging for standardization in highly complex systems, such as Information and Communication Technology (ICT) systems, where a large number of domains and components are involved, along with various types of stakeholders. In order to deal with such complexity and variations, a systematic approach of standardization roadmapping has been used in many technology-leading countries as a strategic policy tool for supporting effective management of standardization. Despite its wide adoption, the current understanding of standardization roadmapping is somewhat limited, leaving significant challenges for policymakers and standards organizations in terms of how to structure and manage roadmapping exercises, and how the government should get involved. In this regard, the current research explores existing standardization roadmaps in various contexts related to ICT systems (ICT in Korea, Smart Grid in the US, and electromobility in Germany), as there is a particular need for systematic development of strategies for such complex systems of ICT. Focusing on various aspects of standardization roadmapping exercises such as their structures, processes, and participants, their common features and key characteristics are identified. Comparing these roadmaps also reveal distinct differences between standardization roadmapping approaches adopted by different countries in different contexts. Based on lessons learnt from existing practices, the study finally provides insight for the Korean ICT standards community on the ways in which their standardization roadmapping approach can be improved to support anticipatory management of standardization activities more effectively. It is expected that the current research can not only provide increased understanding of standardization roadmaps, but also help policymakers and standards organizations to develop more effective strategies for supporting innovation through the systematic management of standardization.

• Korean Journal of Logic
• /
• v.14 no.1
• /
• pp.77-102
• /
• 2011

This paper is about the problems that Quine's criterion of ontological commitment creates for Nominalists. Quine's clear criterion of ontological commitment, summarized as "to be is to be the value of a variable", means that when we accept a sentence to be true, we are committed to the existence of things that must exist for the sentence to be true. The criterion causes problems for Nominalists. According to Quine's criterion, Nominalists who consider "Humility is a virtue" as true should accept the existence of the property, humility. However, Nominalists are reluctant to accept that properties such as humility exist, although they wish to accept what is meant by "humility is a virtue". The way out of this predicament is presenting a paraphrase which delivers what Nominalists wanted to say through the original sentence without ontological commitment to the property. Several attempts were made to paraphrase such sentences, only to fail. In this paper, successful paraphrases will be presented to cope with previously discussed difficulties. Beforehand, several issues involved in the Quine's criterion will be clarified. Also, Lewis's critical objection that we should give up the business of paraphrase will be discussed.

• Journal of Magnetics
• /
• v.6 no.2
• /
• pp.47-52
• /
• 2001

We present the magnetisation reversal dynamics of epitaxial Fe thin films grown on GaAs(001) and InAs(001) studied as a function of field sweep rate in the range 0.01-160 kOe/s using magneto-optic Kerr effect (MOKE). For 55 and 250 ${\AA}$ Fe/GaAs(001), we find that the hysteresis loop area A follows the scaling relation $A\propto H_{\alpha} \;with\; \alpha=0.03\sim0.05$ at low sweep rates and 0.33~0.40 at high sweep rates. For the 150${\AA}$ Fe/InAs(001) film, $\alpha$is found to be ~0.02 at low sweep rates and ~0.17 at high sweep rates. The differing values of $\alpha$ are attributed to a change of the magnetisation reversal process with increasing sweep rate. Domain wall motion dominates the magnetisation reversal at low sweep rates, but becomes less significant with increasing sweep rate. At high sweep rates, the variation of the dynamic coercivity $H_c{^*}$ is attributed to domain nucleation dominating the reversal process. The results of magnetic relaxation studies for easy-axis reversal are consistent with the sweeping of one or more walls through the entire probed region (~100$\mu m$). Domain images obtained by scanning Kerr microscopy during the easy cubic axis reversal process reveal large area domains separated by zigzag walls.

• The Korean Journal of Physiology and Pharmacology
• /
• v.16 no.3
• /
• pp.167-174
• /
• 2012

Natural killer (NK) cells provide one of the initial barriers of cellular host defense against pathogens, in particular intracellular pathogens. Because bone marrow-derived hematopoietic stem cells (HSCs), lymphoid protenitors, can give rise to NK cells, NK ontogeny has been considered to be exclusively lymphoid. Here, we show that porcine c-$kit^+$ bone marrow cells (c-$kit^+$ BM cells) develop into NK cells in vitro in the presence of various cytokines [interleukin (IL)-2, IL-7, IL-15, IL-21, stem cell factor (SCF), and fms-like tyrosine kinase-3 ligand (FLT3L)]. Adding hydrocortisone (HDC) and stromal cells greatly increases the frequency of c-$kit^+$ BM cells that give rise to $CD2^+CD8^+$ NK cells. Also, intracellular levels of perforin, granzyme B, and NKG2D were determined by RT-PCR and western blotting analysis. It was found that of perforin, granzyme B, and NKG2D levels significantly were increased in cytokine-stimulated c-$kit^+$ BM cells than those of controls. And, we compared the ability of the cytotoxicity of $CD2^+CD8^+$ NK cells differentiated by cytokines from c-$kit^+$ BM cells against K562 target cells for 28 days. Cytokines-induced NK cells as effector cells were incubated with K562 cells as target in a ratio of 100 : 1 for 4 h once a week. In results, $CD2^+CD8^+$ NK cells induced by cytokines and stromal cells showed a significantly increased cytotoxicity 21 days later. Whereas, our results indicated that c-$kit^+$ BM cells not pretreated with cytokines have lower levels of cytotoxicity. Taken together, this study suggests that cytokines-induced NK cells from porcine c-$kit^+$ BM cells may be used as adoptive transfer therapy if the known obstacles to xenografting (e.g. immune and non-immune problems) were overcome in the future.