• 천문학회보
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• 제42권2호
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• pp.54.3-55
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• 2017

The Deep Lens Survey (DLS), a precursor to the Large Synoptic Survey Telescope (LSST), is a 20 deg2 survey carried out with NOAO's Blanco and Mayalltelescopes. DLS is unique in its depth reaching down to ~27th mags in BVRz bands. This enables a broad redshift baseline and is optimal for investigating cosmological evolution of the large scale structure. Galaxy-galaxylensing is a powerful tool to estimate averaged matter distribution around lensgalaxies by measuring shape distortions of background galaxies. The signal from galaxy-galaxy lensing is sensitive not only to galaxy halo properties, but also to cosmological environment at large scales. In this study, we measure galaxy-galaxy lensing and galaxy clustering, which together put strong constraints on the cosmological parameters. We obtain significant galaxy-galaxy lensing signals out to ~20 Mpc while tightly controlling systematics. The B-mode signals are consistent with zero. Our lens-source flip test indicates that minimal systematic errors are present in DLS photometric redshifts. Shear calibration is performed using high-fidelity galaxy image simulations. We demonstrate that the overall shape of the galaxy-galaxy lensing signal is well described by the halo model comprised of central and non-central halo contributions. Finally, we present our preliminary constraints on the matter density and the normalization parameters.

• 천문학회보
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• 제44권2호
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• pp.73.4-73.4
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• 2019

Most of the galaxy mass is known to be occupied by dark matter. However, it is difficult to directly measure the mass and distribution of dark matter in a galaxy. Recently, the velocity dispersion of the stellar population in a galaxy's center has been suggested as a possible probe of the mass of the dark matter halo. In this study, we test and verify this hypothesis using the kinematics of the satellite galaxies of isolated galaxies. We use the Friends-of-Friends (FoF)algorithm to build a catalog of primary galaxies and their satellite galaxies from the Sloan Digital Sky Survey (SDSS) DR 12. We calculate the dynamical mass of the primary galaxies from the velocity dispersion of their satellite galaxies. We then investigate the correlation between the dynamical mass and the central velocity dispersion of the primary galaxies. The stellar velocity dispersion of the central host galaxies has a strong linear correlation with the velocity dispersion of their satellite galaxies. Also, the stellar velocity dispersion of the central galaxy is strongly correlated with the dynamical mass of the galaxy, which can be described as a power law. The results of this study show that the central velocity dispersion of the primary galaxies is a good proxy for tracing the mass of dark matter halo.

• 대한의용생체공학회:의공학회지
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• 제33권4호
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• pp.169-176
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• 2012

Tumor cell morphology is closely related to its migratory behaviors. An active tumor cell has a highly irregular shape, whereas a spherical cell is inactive. Thus, quantitative analysis of cell features is crucial to determine tumor malignancy or to test the efficacy of anticancer treatment. We use 3D time-lapse phase-contrast microscopy to analyze single cell morphology because it enables to observe long-term activity of living cells without photobleaching and phototoxicity, which is common in other fluorescence-labeled microscopy. Despite this advantage, there are image-level drawbacks to phase-contrast microscopy, such as local light effect and contrast interference ring. Therefore, we first corrected for non-uniform illumination artifacts and then we use intensity distribution information to detect cell boundary. In phase contrast microscopy image, cell is normally appeared as dark region surrounded by bright halo ring. Due to halo artifact is minimal around the cell body and has non-symmetric diffusion pattern, we calculate cross sectional plane which intersects center of each cell and orthogonal to first principal axis. Then, we extract dark cell region by analyzing intensity profile curve considering local bright peak as halo area. Finally, we calculated the Fourier descriptor that morphological characteristics of cell to classify tumor cells into active and inactive groups. We validated classification accuracy by comparing our findings with manually obtained results.

• 대한두경부종양학회지
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• 제15권1호
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• pp.66-69
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• 1999

Background and Objectives: It is critical to distinguish benign from malignant thyroid nodule and to select a patient for surgery. Even though the U/S study dose not make great contribution to diagnose a malignant thyroid nodule, it is widely used in the evaluation of anatomic feature of thyroid. The authors tried to estimate the efficacy of the U/S study in preoperative diagnosis of malignant thyroid nodule. Materials and Method: At the department of General Surgery of Ajou University, 75 patients who were operated after diagnosis with thyroid nodule by U/S study between July 1996 to June 1997 were retrospectively analyzed. By comparing the U/S impression that implies malignant thyroid nodule to FNAC and post-operative pathologic results ware as follows. Results: 1) Absence of cystic change, presence of internal hypoechogenicity, lobulation, calcification, thick and irregular halo, and nodule more than 4cm in diameter on U/S were considered significant statistically for the diagnosis of malignancy(Chi-square test, p<0.05) 2) Presence of internal hypoechogenicity or thick and irregular halo has the validity in Logistic regression analysis. 3) FNAC was done in 65 case. 19 case were malignant, 11 case were suspicious and 46 patients were benign (sensitivity 52.6%, specificity 87%). 4) The findings of U/S which are hypoechogenic and thick and irregular halo show 82% sensitivity and 97% specificity. In combination with the findings of FNAC that imply benign or suspicious lesions, the sensitivity was 100% and the specificity was 97%. Conclusion: This study suggest that the hypoechogenicity and thick and irregular halo on U/S are important information for the diagnosis of thyroid malignancy which were considered benign or suspicious after FNAC.

• Archives of Pharmacal Research
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• 제17권6호
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• pp.483-486
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• 1994

A series of 6-[N-(halophenyl)amino]-7-chloro-5, 8-quinolinedione derivatives 1-10 were tested for antifungal susceptibilities, in vitro, aginst pathogenic Candida species such as C. ablbicans, C glabrata, C. krusei, C. parapsilosis and C. tropicalis. The MICs were determined by the standard macrodilution techniques, according to the NCCLS 1992 guidelines. The 6-[N-(halo-standard macrodilution techniques, according to the NCCLS 1992 gidelines. The 6-[N-(halo-phenyl)amino]-7-chloro-5, 8-quinolinedione derivatives showed generally potent antifungal activities against pathogenic Candida species. Among them, derivative 1, 2, 5, and 7 showed more potent antifungal activities than kietoconazole. All derivatives 1-10 had specially potent activities against C. torpicalis. Derivative 1 and 2 containing 9N-3, 4-dihalo-phenyl)amino moiety exhibited the potent antifugal activities. Derivative 2 with (3, 4-dichlorophenyl)amino substitutent was the most effetive in preventing the growth of Candida species at MICs 4.mu.g/ml respectively.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.191-193
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• 2000

B. macerans 유래의 CGTase를 yeast surface display기술을 이용하여 S. cerevisiae의 표면에 발현된 것을 halo-test와 immunofluorescence microscopy와 flow cytometry를 통하여 확인하였다. 재조합 효모는 효소의 cyclization작용을 저해하고 CD의 분해작용을 촉진하는 glucose와 maltose를 제거하는 발효공정과 표면 발현된 CGTase의 cyclization 공정을 동시에 수행할 수 있어 CD의 생산, 분리공정을 효율적으로 개선하였다.

• 공업화학
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• 제18권1호
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• pp.17-23
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• 2007

제지용 무기안료에 항균기능과 광촉매 탈취기능을 부여하기 위해 hybridization system을 이용하여 Ag 용액과 $TiO_2$로 표면 개질 처리하여 기능성 무기안료를 제조하고, 이를 이용하여 항균 및 탈취 기능을 갖는 특수지를 제조한 후 내항균 특성을 평가하였다. 내항균 평가로는 균의 생성여부를 눈으로 직접 확인 할 수 있는 halo test법, 균들의 생육 저하효과를 확인하는 방법인 inhibition growth test와 정균감소법을 사용하였다. 또한 제조된 항균기능성 특수지를 벽지용도로 적용하고자 하였으며, 내항균 평가 시 항균벽지 주위로 선명한 클리어 존이 형성되어 균의 성장 억제를 육안으로 확인할 수 있었다. 항균 및 탈취기능을 지니는 특수지의 휘발성 유기화합물 분해능 평가를 위한 benzene의 광촉매 분해 효율실험에서 반응시간 80min 동안 45~50%의 제거효율을 보였으며, 반응시간 30 min 정도에서 분해효율이 90% 이상 도달함을 알 수 있었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.159-160
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• 2020

This study examined the potentials for developing a biological coating material with high chloride resistance. The bacteria strains isolated were Halomonas alkaliphile, Halomonas venusta, and Sulfidobacter mediterraneus. Test results revealed that the developed approach is very promising in reducing the chloride ion diffusion coefficient of concrete.

• 대한인간공학회지
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• 제6권1호
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• pp.41-44
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• 1987

Researches were made on foot-warming, anti-bacteria and deodorant treatment. Feet, the very important organ to human body, perspire much and their temperature is lower than those of other parts. Hence, keeping feet warm, sanitary and deodorant is the area of this study. Latex sponge of activated carbon, impregnated open cell foam, treated with Vikol DZ-anti-bacteria finishing agent, was developed and tested for warmth-keeping by KSK 0560 test method and for sanitization by AATCC 90 HALO test method and for deodorization by wearing tests. The results show that the new developed latex spongee has warmth-keeping ratio of 2.5 times higher than that of the conventional spong and it has an excellent anti-bacteria effect. Actual wearing function tests also show that it improves significantly the performance of deodorization, sanitization, warmth-keeping and bulkiness.

• 한국염색가공학회지
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• 제6권4호
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• pp.1-8
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• 1994

To improve the antimicrobial activity and crease resistance of Korean traditional Hansan ramie fabrics, partially saponified polyethylene(PPS) was used as a softening water repellent agent and 3-(trimethoxysilyl)propyl dimethyl octadecyl ammonium chloride(QAC) as a antimicrobial agent. The antimicrobial activity was effective by treatments of PPS, QAC and PPS/QAC for shake flask test. For the halo test, PPS/QAC showed good antimicrobial activity. It was found that the desirable composition of H$_{2}$O/PPS/QAC is 98/1/1 for improving the antimicrobial activity and crease resistance of the fabrics.