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A Method to Obtain the CT Attenuation Coefficient and Image Noise of Various Convolution Kernels in the Computed Tomography (Convolution Kernel의 종류에 따른 CT 감약계수 및 노이즈 측정에 관한 연구)

  • Kweon, Dae-Cheol;Yoo, Beong-Gyu;Lee, Jong-Seok;Jang, Keun-Jo
    • Korean Journal of Digital Imaging in Medicine
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    • v.9 no.1
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    • pp.21-30
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    • 2007
  • Our objective was to evaluate the CT attenuation coefficient and noise of spatial domain filtering as an alternative to additional image reconstruction using different kernels in abdominal CT. Derived from thin collimated source images was generated using abdomen B10 (very smooth), B20 (smooth), B30 (medium smooth), B40 (medium), B50 (medium sharp), B60 (sharp), B70 (very sharp) and B80 (ultra sharp) kernels. Quantitative CT coefficient and noise measurements provided comparable HU (hounsfield) units in this respect. CT attenuation coefficient (mean HU) values in the abdominal were 60.4$\sim$62.2 HU and noise (7.6$\sim$63.8 HU) in the liver parenchyma. In the stomach a mean (CT attenuation coefficient) of -2.2$\sim$0.8 HU and noise (10.1$\sim$82.4 HU) was measured. Image reconstructed with a convolution kernel led to an increase in noise, whereas the results for CT attenuation coefficient were comparable. Image medications of image sharpness and noise eliminate the need for reconstruction using different kernels in the future. CT images increase the diagnostic accuracy may be controlled by adjusting CT various kernels, which should be adjusted to take into account the kernels of the CT undergoing the examination.

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Culture Conditions Affecting Spore Germination, Prothallus Propagation and Sporophyte Formation of Dryopteris nipponensis Koidz. (참지네고사리의 포자발아, 전엽체 및 포자체 번식에 영향을 미치는 배양 조건)

  • Jang, Bo Kook;Cho, Ju Sung;Lee, Ki Cheol;Lee, Cheol Hee
    • Horticultural Science & Technology
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    • v.35 no.4
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    • pp.480-489
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    • 2017
  • We investigated a suitable method for in vitro germination of spores, propagation of prothalli, and the formation of sporophytes in the fern Dryopteris nipponensis Koidz. Spore germination rate was relatively high regardless of culture medium. Prothallus development was faster in Knop medium than in Murashige and Skoog (MS) media. Prothalli used in all experiments were obtained from germinated spores, and were cultivated in different concentrations of media components. The active formation of sexual organs such as antheridium made 1MS medium suitable for prothallus propagation, although there was a lower propagation ratio compared to Knop medium. Growth and morphogenesis of prothalli were most effective on 1MS medium containing 2% sucrose, and 60 mM of total nitrogen source with 20:40 mM ratio of $NH_4{^+}:NO_3{^-}$. To select a suitable soil composition for sporophyte formation, ground prothalli were cultivated on single and mixed soils using bed soil, peat moss, perlite, and decomposed granite for 14 weeks. Bed soil promoted sporophyte formation and growth regardless of single or mixed use. In particular, a mixture of bed soil and decomposed granite in a 2:1 ratio (v:v) led to accelerated sporophyte formation ($0.83/cm^2$).

Development of Portable Laryngeal Stroboscope (휴대형 후두 스트로보스콥의 개발)

  • Lee, Jae-Woo;Kwon, Soon-Bok;Lee, Byung-Joo;Lee, Jin-Choon;Goh, Eui-Kyung;Chon, Kyong-Myong;Wang, Soo-Geun;Ro, Jung-Hoon
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.17 no.1
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    • pp.28-37
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    • 2006
  • Purpose: Evaluation of vocal cord vibration is very important in cases of voice disorders. There are several equipments for examining the vocal fold vibration such as laryngeal stroboscope, ultra high-speed digital imaging system, and videokymograph. Among these, laryngeal stroboscope is the most popular equipment because of easy to examine the laryngeal pathology. However, current laryngo-stroboscopes are too bulky to move and relatively expensive. The purpose of this research is to develope a portable laryngeal stroboscope of equivalent performance with the current equipments. Methods and Materials: Recently developed high luminescent white LEDs(light emitting diodes) are placed at the head of the endoscope as light sources for the CCD image sensor which is also placed at the head with imaging lens. This arrangement eliminates the bulky light source like expensive halogen or xenon lamps as well as the optical light guiding cables. The LEDs are controlled to flash in phase with the voice frequency of the examinee. The CCD captures these strobo images and converts them into video signals for examinations. Results: There was no functional differences between preexisting stroboscope and the newly developed stroboscope of this study. LED light sources and microprocessor based control circuits of the stroboscope enabled the development of flicker-less, hand-held, portable and battery-operating stroboscope. Conclusion: The developed stroboscope is cost-effective, small-sized, easy to use and very easy desirable to bring and to use in any place.

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Effect of By-Product Gypsum Fertilizer on Methane Gas Emissions and Rice Productivity in Paddy Field

  • Park, Jun-Hong;Sonn, Yeon-Kyu;Kong, Myung-Suk;Zhang, Yong-Seon;Park, Sang-Jo;Won, Jong-Gun;Lee, Suk-Hee;Seo, Dong-Hwan;Park, So-Deuk;Kim, Jang-Eok
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.1
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    • pp.30-35
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    • 2016
  • Rice cultivation in paddy field affects the global balance of methane ($CH_4$) as a key greenhouse gas. To evaluate a potential use of by-product gypsum fertilizer (BGF) in reducing $CH_4$ emission from paddy soil, $CH_4$ fluxes from a paddy soil applied with BGF different levels (0, 2, 4 and $8Mg\;ha^{-1}$) were investigated by closed-chamber method during rice cultivation period. $CH_4$ flux significantly decreased (p<0.05) with increasing level of BGF application. $8Mg\;ha^{-1}$ of BGF addition in soil reduced $CH_4$ flux by 60.6% compared to control. Decreased soil redox potential (Eh) resulted in increasing $CH_4$ emission through a $CO_2$ reduction reaction. The concentrations of dissolved calcium (Ca) and sulfate ion (${SO_4}^{2-}$) in soil pore water were significantly increased as the application rate of BGF increased and showed negatively correlations with $CH_4$ flux. Decreased $CH_4$ flux with BGF application implied that ${SO_4}^{2-}$ ion led to decreases in electron availability for methanogen and precipitation reaction of Ca ion with inorganic carbon including carbonate and bicarbonate as a source of $CH_4$ formation under anoxic condition. BGF application also increased rice grain yield by 16% at $8Mg\;ha^{-1}$ of BGF addition. Therefore, our results suggest that BGF application can be a good soil management practice to reduce $CH_4$ emission from paddy soil and to increase rice yield.

Sterols from the Seed of Cowpea (Vigna sinensis K.) (동부로부터 sterol의 분리 동정)

  • Cui, En-Ji;Park, Hee-Jung;Wu, Qian;Chung, In-Sik;Kim, Ji-Young;Baek, Nam-In
    • Journal of Applied Biological Chemistry
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    • v.53 no.2
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    • pp.77-81
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    • 2010
  • The seed of cowpea (Vigna sinensis K.) was extracted with 80% aqueous methanol (MeOH). And the concentrated extract was partitioned with ethyl acetate (EtOAc), n-butanol (n-BuOH) and $H_2O$, successively. The repeated silica gel and octadecyl silica gel (ODS) column chromatographic separations for the EtOAc and n-BuOH fractions led to isolation of four sterols. And the chemical structures of the compounds were determined as a mixture of stigmasterol and $\beta$-sitosterol with the ratio of 4 to 3 (1), 7-ketositosterol (2), and stigmasterol 3-O-$\beta$D-glucopyranoside (3) from the interpretation of spectroscopic data including nuclear magnetic resonance (NMR) spectrum metric, mass (MS) spectrum metric and infrared (IR) spectroscope. This study reports the first isolation of $\beta$-sitosterol, 7-ketositosterol, and stigmasterol 3-O-$\beta$-D-glucopyranoside from the seed of Vigna sinensis K. In addition, compound 2, 7-ketositosterol, is rarely occurred in natural source including plant.

Analysis of Molecular Expression in Adipose Tissue-Derived Mesenchymal Stem Cells : Prospects for Use in the Treatment of Intervertebral Disc Degeneration

  • Jin, Eun-Sun;Min, Joongkee;Jeon, Sang Ryong;Choi, Kyoung Hyo;Jeong, Je Hoon
    • Journal of Korean Neurosurgical Society
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    • v.53 no.4
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    • pp.207-212
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    • 2013
  • Objective : Recent studies have shown encouraging progress toward the use of autogenic and allogenic mesenchymal stem cells (MSCs) to arrest, or even lead to partial regeneration in, intervertebral disc (IVD) degeneration. However, this technology is still in its infancy, and further development is required. The aim of this study was to analyze whether rat adipose-derived mesenchymal stem cells (ADMSC) can differentiate towards IVD-like cells after treatment with transforming growth factor ${\beta}3$ (TGF-${\beta}3$) in vitro. We also performed quantitative analysis of gene expression for ADMSC only, ADMSCs treated with TGF-${\beta}3$, and co-cultured ADMSCs treated with TGF-${\beta}3$. Methods : ADMSCs were sub-cultured to homogeneity and used in fluorocytometry assays for CD11, CD45, and CD90/Thy1. ADMSCs were differentiated in spheroid culture towards the chondrogenic lineage by the presence of TGF-${\beta}3$, dexamethasone, and ascorbate. We also co-cultured pure ADMSCs and nucleus pulposus cells in 24-well plates, and performed immunohistochemical staining, western blotting, and RT-PCR for quantitative analysis of gene expression. Results : Results of fluorocytometry were positive for CD90/Thy1 and negative for CD11 and CD45. TGF-${\beta}3$-mediated induction of ADMSCs led to the expression of the differentiation markers of intervertebral disc-like cells, such as aggrecan, collagen II, and sox-9. Co-cultured ADMSCs treated with TGF-${\beta}3$ showed higher expression of differentiation markers and greater extracellular matrix production compared with ADMSCs treated with TGF-${\beta}3$ alone. Conclusion : ADMSC treated with TGF-${\beta}3$ may be an attractive source for regeneration therapy in degenerative IVD. These findings may also help elucidate the pathologic mechanism of MSC therapy in the degeneration of IVD in vivo.

RNAi-Mediated Gene Silencing of Trcot1 Induces a Hyperbranching Phenotype in Trichoderma reesei

  • Gao, Fei;Li, Mengzhu;Liu, Weiquan;Bai, Yingguo;Tao, Tu;Wang, Yuan;Zhang, Jie;Luo, Huiying;Yao, Bin;Huang, Huoqing;Su, Xiaoyun
    • Journal of Microbiology and Biotechnology
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    • v.30 no.2
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    • pp.206-215
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    • 2020
  • Trichoderma reesei is the major filamentous fungus used to produce cellulase and there is huge interest in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted in retarded sporulation on potato dextrose agar and dwarfed colonies on minimal medium agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with hyphal growth unit length values decreased to 73.0 ㎛/tip compared to 239.8 ㎛/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.

Genomic and Proteomic Analysis of Microbial Function in the Gastrointestinal Tract of Ruminants - Review -

  • White, Bryan A.;Morrison, Mark
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.6
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    • pp.880-884
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    • 2001
  • Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.

Is Colorectal Cancer A Western Disease? Role of Knowledge and Influence of Misconception on Colorectal Cancer Screening among Chinese and Korean Americans: A Mixed Methods Study

  • Lu, Xiaoxiao;Holt, Cheryl L;Chen, Julia C;Le, Daisy;Chen, Jingjing;Kim, Gil-yong;Li, Jun;Lee, Sunmin
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.11
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    • pp.4885-4892
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    • 2016
  • Background: Chinese and Korean Americans have lower colorectal cancer (CRC) screening rates than other racial/ ethnic groups, which may be explained by a low level of CRC knowledge and a high level of misconceptions. This study explores the role of knowledge in CRC screening among these groups. Methods: Chinese (N=59) and Korean (N=61) Americans older than 50 were recruited from the Washington D.C. Metropolitan area. They completed a detailed survey and participated in focus groups to discuss their knowledge on CRC and CRC screening. Seventeen physicians, community leaders, and patient navigators participated in key informant interviews. Using a mixed methods approach, data were analyzed quantitatively and qualitatively. Results: Participants lacked knowledge about CRC and CRC screening. More than half did not know that screening begins at age 50 and there are several types of tests available. More than 30% thought CRC screening was not necessary if there were no symptoms or there was nothing they could do to prevent CRC. Focus group findings suggested understanding about CRC was limited by an inadequate source of linguistically and culturally relevant health information. For example, many participants considered CRC a western condition mainly caused by unhealthy diet. This led to under-estimations about their susceptibility to CRC. Knowledge was positively associated with self-reported screening. Participants who had higher knowledge scores were more likely to report ever having had a colonoscopy and confidence in ability to have CRC screening. Conclusions: Mixed-methods analysis provides multi-faceted perspectives on CRC knowledge and its influence on screening. Study findings can help inform interventions to increase CRC screening among Chinese and Korean Americans.

A Study on the Environmental Factors Affecting the Population of the Wintering Waterbirds in Wonju-Stream (원주천의 월동수조류 군집에 영향을 미치는 환경요인 연구)

  • Park, Yung Wook;Lee, Hwang Goo;Won, Kyung Ho;Choi, Jun Kil
    • Journal of Wetlands Research
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    • v.19 no.4
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    • pp.409-422
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    • 2017
  • In order to understand the environmental factors affecting the waterbird community in winter, we divided the watershed into 6 sections and investigated the size of the stream, the water quality, benthic invertebrates, and fish including birds. The influences on the community of water birds in Wonju stream were river structure, temperature and water quality. Among the structure of the river, the factors affecting the waterbird community in winter were the width of the stream and the width of the flowing water. The wider the width, the more species and the number of the winter waterbirds were. As the width of river water was wide, the smaller the width and width of the waterway, the fewer the population. The temperature changes of the wintering season affected the community of water birds because it led to freezing of rivers. The sections that were not frozen showed a significant increase and decrease in the temperature drop and rise. The values of pH, water temperature, COD, BOD, TN, TP and total E. coli increased with the increase of the downstream waterbirds population in the water quality survey. The water quality of S6 was affected by the downstream sewage treatment plant The number of wintering waterbirds was also highest. The effluent from the sewage treatment plant seems to have a considerable influence on the water quality. The increase of several items such as TN promotes the nutrition of the river, which leads to the accumulation of organic matter and the proliferation of aquatic organisms. This may be the cause of the increase in winter waterbirds as a food source. The benthic macroinvertebrate communities and fish communities did not show any correlation with the wintering water-birds communities.