• Korean Journal of Microbiology
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• v.44 no.2
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• pp.98-104
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• 2008

We constructed the null mutants of fission yeast Schizosaccharomyces pombe rsml gene that is thought to be involved in mRNA export. Though rsm1 gene is not essential for growth, the null mutant strain constructed by replacing the rsm1-coding region with an $kan^{r}$ gene showed growth retardation and mRNA export defects compared to wild type strain. We constructed double mutants which harbor rsm1 null allele and mutant allele of genes involved in mRNA export. The mex67 or npp106 null allele, when combined with rsm1 null allele, showed an additive effect on growth retardation and mRNA export defects. On the other hand, the thp1 null allele restored the defects of growth and mRNA export of rsm1 null mutant. These results suggest that rsm1 plays a role in mRNA export from the nucleus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.1
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• pp.76-90
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• 1993

To clarify the relations between photoperiodism and x-organ of eyestalks to the control of gonadal maturation in a freshwater prawn, Macrobrachium nipponense, the present investigation was performed with following examinations: 1) the influence of water temperature and daylength on the control of gonadal maturation, 2) the effect of eyestalk ablation on the gonadal maturation, 3) the seasonal variation of histology of MEX-organ (medulla externa X-organ) in the eyestalk. In previtellogenesis period (December${\sim}$March) and vitellogenesis period (April${\sim}$May), gonadal maturation was considerablely influnced by water temperature. In these periods, GSI increased and gonads were matured with water temperature rising without regard to photoperiod conditions (12L/12D and 15L/9D). In spawning period (June${\sim}$August), however, gonadal maturation was influenced by photoperiod condition. While high value of GSI was kept at long photoperiod regime (15L/9D), GSI was decreased at short photoperiod regime (12L/12D). In resting period (September${\sim}$November), no rematuration was occurred at all the experimental regimes combinated with water temperatures ($16^{\circ}C,\;22^{\circ}C,\;28^{\circ}C$) and photoperiod (12L/12D, 15L/9D). Effect of X-organ which inhibite the gonadal maturation was stronger in resting period than that in previtellogenesis and ealy spawning periods by observations on the effectiveness of eyestalk ablation on the gonadal maturation. In MEX-organ of eyestalk, the number of neurosecretory cells of which size was over $20{\mu}m$ in diameter varied according to the reproductive cycle. The number of cells increased $77{\pm}12$ in resting period, and decreased $55{\pm}7$ in vitellogenesis period. Volume of Bellonci's organ, however, increased in vitellogenesis period in comparison with that in resting period.

• Journal of Microbiology
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• v.42 no.1
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• pp.32-36
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• 2004

We have previously isolated three synthetic lethal mutants from Schizosaccharomyces pombe in order to identify mutations in the genes that are functionally linked to spmex67 with respect to mRNA export. A novel rsm1 gene was isolated by complementation of the growth defect in one of the synthetic lethal mutants, SLMex1. The rsml gene contains no introns and encodes a 296 amino-add-long protein with the RING finger domain, a C3HC4 in the N-terminal half. The Δrsm1 null mutant is viable, but it showed a slight poly(A)$\^$＋/ RNA accumulation in the nucleus. Also, the combination of Δrsm1 and Δspmex67 mutations confers synthetic lethality that is accompanied by the severe poly(A)$\^$＋/ RNA export defect. These results suggest that rsm1 is involved in mRNA export from the nucleus.

• Journal of Communications and Networks
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• v.4 no.4
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• pp.363-369
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• 2002

Towards the deployment of 3rd generation systems, Virtual Home Environment (VHE), stemming from 3GPP, appears to be a powerful concept advocating the provision and delivery of personalized services to roaming users across network and terminal boundaries. This paper aims to expose the pathway for materializing the VHE concept, via the specification, implementation and evaluation of a prototype. Core aspects for realizing the concept such as the business and roaming models are presented, while a VHE enabling architecture utilizing key technologies (OSA/Parlay, MExE, and USAT) is introduced. The proposed architecture has already been evaluated by performing an initial trial demonstration. Currently it is being extended to support VHE service provision to roaming users, an aspect to be addressed by the final trial.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.105.2-105.2
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• 2012

The upper ionosphere of Mars has been explored by many spacecraft like Mariners, Mars, Viking, and recently by MGS and MEX. MARSIS (Mars Advanced Radar for Subsurface and Ionospheric Sounding) aboard Mars Express Orbiter is operating from August 2005. MARSIS provides topside ionospheric traces, of which yield electron density profiles for altitudes above the primary ionospheric peak. A large amounts of data is useful for investigation of the Martian ionospheric environments under the changing conditions like solar activity, seasons, and solar zenith angle. We studied the characteristics of the Martian ionosphere through analysis of MARSIS data in the various conditions. We expect that our results contribute for understanding of the Martian ionospheric environment.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.91-97
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• 2018

The evolutionally conserved TREX complex member, Yra1/ALY, belongs to the REF (RNA and export factor binding proteins) family of hnRNP-like proteins, which has been implicated in multiple processes including transcription, nuclear RNA stability, and mRNA export. Fission yeast, Schizosaccharomyces pombe, genome encodes two members of REF proteins. In addition to Mlo3 known previously as an mRNA export factor, there is the other REF protein, Tho4, which is predicted as a component of THO complex. Here we showed that deletion of tho4 (SPBC106.12c) gene does not inhibit both growth and nuclear mRNA export. However, overexpression of tho4 displays growth retardation and slight accumulation of $poly(A)^+$ RNA in the nucleus. Neither ${\Delta}tho4$ ${\Delta}mlo3$ nor ${\Delta}tho4$ ${\Delta}mex67$ double mutants exhibit additive growth defect. Moreover, yeast two-hybrid and co-immunoprecipitation analysis did not show that the Tho4 protein interacted with any members of TREX complex and mRNA export factor Rae1. Contrary to expectation, these observations support that the S. pombe Tho4 is not a component of TREX complex, and not directly involved in bulk mRNA export from the nucleus.

• ALGAE
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• v.35 no.3
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• pp.237-252
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• 2020

Temperate rocky reefs dominated by the giant kelp, Macrocystis pyrifera, support diverse assemblages of benthic macroalgae that provide a suite of ecosystem services, including high rates of primary production in aquatic ecosystems. These forests and the benthic macroalgae that inhabit them are facing both short-term losses and long-term declines throughout much of their range in the eastern Pacific Ocean. Here, we quantified patterns of benthic macroalgal biomass and irradiance on rocky reefs that had intact kelp forests and nearby reefs where the benthic macroalgae had been lost due to deforestation at three sites along the California, USA and Baja California, MEX coasts during the springs and summers of 2017 and 2018. We then modeled how the loss of macroalgae from these reefs impacted net benthic productivity using species-specific, mass-dependent rates of photosynthesis and respiration that we measured in the laboratory. Our results show that the macroalgal assemblages at these sites were dominated by a few species of stipitate kelps and fleshy red algae whose relative abundances were spatially and temporally variable, and which exhibited variable rates of photosynthesis and respiration. Together, our model estimates that the dominant macroalgae on these reefs contribute 15 to 4,300 mg C m^-2 d^-1 to net benthic primary production, and that this is driven primarily by a few dominant taxa that have large biomasses and high rates of photosynthesis and / or respiration. Consequently, we propose that the loss of these macroalgae results in the loss of an important contribution to primary production and overall ecosystem function.

• Korean Journal of Veterinary Research
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• v.61 no.2
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• pp.12.1-12.9
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• 2021

The mosquito-borne pathogen Zika virus may result in neurological disorders such as Guillain-Barré syndrome and microcephaly. The virus is classified as a member of the Flaviviridae family and its wide spread in multiple continents is a significant threat to public health. So, there is a need to develop animal models to examine the pathogenesis of the disease and to develop vaccines. To examine the clinical profile during Zika virus infection, we infected neonatal and adult wild-type mice (C57BL/6 and Balb/c) and compared the clinical signs of African-lineage strain (MR766) and Asian-lineage strain (PRVABC59, MEX2-81) of Zika virus. Consistent with previous reports, eight-week-old female Balb/c mice infected with these viral strains showed no changes in body weight, survival rate, and neurologic signs, but demonstrated increases in the weights of spleens and hearts. However, one-day-old neonates showed significantly lower survival rate and body weight with the African-lineage strain than the Asian-lineage strain. These results confirmed the pathogenic differences between Zika virus strains. We also evaluated the clinical responses in neonatal and adult mice of different strains. Our findings suggest that these are useful mouse models for characterization of Zika virus for vaccine development.

• Magazine of the Korea Concrete Institute
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• v.3 no.3
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• pp.129-139
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• 1991

The mechanical hehavior of relIlforced concrete beams with steel fibers is investigated 111 the present study. An expenmental program was set up and several series of rem forced concrete beams have been tested, including two senes of singly-reinforced concrete beams and one senes of doubly-reinforced concrete beams. It was found from th, :se measurements that the crack widths lIlcrease almost llIlearly With the lIlcrease of steel stress and that the crack Widths at the same loadlJ1g stages are greatly reduced as the contents of steel fibers increase. The present study also IJ1chcates that the ductiiIty and the ultJmate resistance are remarkably enhanced due to the addition of steel fibers. A theoretical mex1e1 for the flexural analysis of fiber-reinforced concrete beam which takes into account the effects of fibers JS also proposed.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.5
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• pp.661-670
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• 2007

To investigate the market potential for developing Gochujang(a traditional Korean hot pepper soybean paste) products in the UK including the European market, a qualitative consumer study utilizing focus groups was conducted on the $23rd{\sim}25^{th}$ of May, 2005. The focus group approach utilizes small groups of consumers and is very effective in determining the ways in which a product can be used, by examining consumer perceptions on the overall sensory properties of a product as well as variations in taste, flavour, and texture. A series of six consumer group studies were carried out in three different locations around the UK. Each group involved approximately eight respondents(a total of 48 respondents) and ran for at least 90 minutes. The respondents were recruited by specific criteria to achieve a cross-section of ages and genders. All respondents purchased, prepared, and ate home-cooked Oriental/Far Eastern cuisine. Consumer reactions to Gochujang in its traditional form, and in manufactured products, were explored in terms of appearance, texture, flavour, and taste the consumers' perceived uses and applications for products were also examined. Many consumers were familiar with ethnic cuisines such as Chinese, Thai, Japanese, Indian, and Tex/Mex, already preparing these foods using various convenience products at home at least twice a week. However, Korean cuisine was not mentioned by any of the respondents. The Gochujang sauce presented during the interview had broad based appeal mainly as a dipping sauce, and to a lesser degree as a marinade. Traditional Gochujang has the potential to inspire consumers who are looking for novel and authentic world cuisine products. From the sensory evaluations of various prototypes developed according to consumer reactions during the focus group interviews, three prototypes(a sauce for chicken, dipping sauce type, and BBQ sauce type) were determined for further consumer preference studies.