• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.30.2-31
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• 2017

Compact elliptical (cE) galaxies are in a rare class of stellar systems characterized by high stellar densities, small sizes, high velocity dispersion, and high metallicity corresponding to elliptical galaxies. cE galaxies have been observed around massive galaxies, so they could be formed under strong influences of tidal stripping and truncation. However, the recent discovery of isolated cE galaxies requires the need of new formation scenarios. We aim at finding cE galaxies in various environments using SDSS DR12, and studying stellar population of cEs as function of environments. Based on the typical properties of cE galaxies, we selected cE candidates by restricting that low-luminosity Mg > 19.5 mag, small sizes Re < 700 pc, and high velocity dispersions ${\sigma}$ > $60kms^{-1}$. Since effect radii of cE candidates are mostly smaller than the seeing size of SDSS photometry, we calculated the effective radius by fitting a Sersic profile. In addition, we assumed that host galaxies have brightness with Mr < -21 mag, and an environmental parameter is computed as distances between cE galaxies and host-galaxies. We found 112 cE galaxies at z < 0.05, which have high sersic indices (mean value is 5.2) similar to the typical massive elliptical galaxies. Mgb values of cE galaxies increase as the distances from the host galaxies decrease. Especially, for cEs close to the host galaxies (NcE; $D_{host}$ < 300 pc), the Mgb values are similar to those of massive elliptical galaxies, which is consistent with the previous studies. On the other hand, cE galaxies distant from the host galaxies (DcE; Dhost >300 pc) have lower Mgb values than the conventional cE. The Mgb values follow the ${\sigma}$-Mgb relation of elliptical galaxies, and are connected to its faint end. This can be explained as a result of different merger histories for differing environments. For example, NcE galaxies are formed by tidal stripping by massive galaxies as suggested by previous studies, but DcE galaxies could be linked with high-redshift spheroids (e.g. red nuggets) which have not evolved into present-day elliptical galaxies because of the environmental influences.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2153-2158
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• 2014

Beclin 1 is a key factor for initiation and regulation of autophagy, which is a cellular catabolic process involved in tumorigenesis. To investigate the role of alternative splicing of Beclin1 in the regulation of autophagy in leukemia cells, Beclin1 mRNA from 6 different types of cell lines and peripheral blood mononuclear cells from 2 healthy volunteers was reversely transcribed, subcloned, and screened for alternative splicing. New transcript variants were analyzed by DNA sequencing. A transcript variant of Beclin 1 gene carrying a deletion of exon 11, which encoded a C-terminal truncation of Beclin 1 isoform, was found. The alternative isoform was assessed by bioinformatics, immunoblotting and subcellular localization. The results showed that this variable transcript is generated by alternative 3' splicing, and its translational product displayed a reduced activity in induction of autophagy by starvation, indicating that the spliced isoform might function as a dominant negative modulator of autophagy. Our findings suggest that the alternative splicing of Beclin 1 might play important roles in leukemogenesis regulated by autophagy.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.117-123
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• 1999

Consumer surplus is to be a value concerning a time horizon. Especially it is very important how long time horizon would be chosen in contingent market. This study aimed to provide causes of difference recreation benefits through discount rate in many aspects. The data were collected by personal interviews with visitors in Songnisan National Park. The respondents answered yes or no, dichotomous choice, on recreation benefits according to a chosen time horizon, one year or five years. The probit model was used in the analysis. In order to avoid the truncation bias of upper bound, the median was chosen as the recreation benefits of visitor. As the result, the value was evaluated to be 16,569 Won for one year and 27,111 Won for five years. The discount rate is estimated 153% annually to coincide different recreation benefits. The reasons of the high discount rate were to be interpreted as following five types : (1)uncertainty of future consumption (2)increasing of probability of the substitution owing to increasing of time horizon (3)recognization of different time horizons (4) effect by the price ratio of goods and utility function (5) overestimation of the recreation benefits owing to a basic premium of payment vehicle.