• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.64.1-64.1
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• 2019

The first high-resolution spectroscopic and new multiband photometric observations of the semi-detached Algol type binary XZ CMi were performed at the Bohyunsan Optical Astronomy Observatory (BOAO) and the Sobaeksan Optical Astronomy Observatory (SOAO), respectively. A total of 34 spectra were obtained using the 1.8 m reflector of the BOAO equipped with the Bohyunsan Optical Echelle Spectrograph to construct the radial velocity (RV) curves of the eclipsing pair. New BVRI photometric light curves were also covered by using the SOAO 61cm reflector and a CCD camera. A detailed analysis of all eclipse timings shows that the orbital period of XZ CMi has varied in an upward parabolic variation superposed on a sinusoidal oscillation with a period of 38.0 yr and a semi-amplitude of 0.0071 days. From the spectral analysis, the effective temperature and the projected rotational velocity of the primary component were determined to be T_eff,1 = 7387±161 K and v₁sini = 122±6 km s^-1, respectively. Our simultaneous synthesis of the double-lined RV and BVRI light curves gives the reliable system parameters of XZ CMi with a mass ratio (q) of 0.314, an orbital inclination (i) of 81.9 deg and a large temperature difference (∆T) of 2481 K. The individual masses and radii of both components are M₁ = 1.91±0.08M_⊙, M₂ = 0.60±0.02M_⊙, R₁ = 1.60±0.02R_⊙, R₂ = 1.13±0.02R_⊙, respectively. Although the primary component is located inside the δ Sct and γ Dor instability strips, no evidence of pulsation in the system was detected. The possible evolutionary status of XZ CMi is discussed.

• Journal of The Korean Association For Science Education
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• v.26 no.7
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• pp.813-825
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• 2006

The purpose of this study was to identify students' conceptions and their conceptualization traits in terms of the explanation of subjects: human, animals, and plants. A questionnaire was specially developed to make sure students' conceptions of evolution, students' explanation patterns with the five evolutionary explanations: creationism, internal will explanation, theological explanations, use and disuse explanation and natural selection after mutation and perceived ideas of evolution in terms of the genetic characters of human, animals and plants. 1,540 elementary, middle and high school students participated in responding to the questions. The data was collected and analyzed cross-sectionally by age. Results showed that students' evolutionary explanations were different among each subject: human, animals and plants. Students had concentrated with more 'theological explanations' than 'internal will explanation' and 'use and disuse explanation' about plant evolution. 'Natural selection after mutation explanation' was less represented in explaining human characters. This result showed that the anthropocentric thoughts had influenced students' evolution conceptions. Accordingly, as student's age, 'theological explanation' and 'internal will explanation' became least used in explaining the theory of creation. 'Use and disuse explanation' attained more representation in their explanation. In addition, the diversity of students' evolutionary explanations was getting less attention as age increases. Among youngers, 'theological explanation', 'internal will explanation' and 'use and disuse explanation' showed an even number of responses. The elders responded with more 'use and disuse explanation'. This result let us infer that 'use and disuse explanation' was strongly adhered to by student cognitive structures. Many students recognized that evolution was a kind of scientific hypothesis with little evidence. They have had a little interest in evolution and conceptualized it through informal educational sources. This study mentions that to teach evolution more effectively, teachers should make 'use and disuse explanation' adhere strongly to students' cognitive structure.

• 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.

• Asia pacific journal of information systems
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• v.18 no.2
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• pp.73-94
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• 2008

When individuals collaborated in virtual settings, communication is medicated through a variety of communication technologies, and is associated not only with communication effectiveness but also with socio-emotional interactions among group members. In this regards, scholars have examined how technology-mediated communication systems can be designed and used to facilitated communication interaction. However, the empirical results of the previous studies have revealed inconsistencies in the effects of communication media on users' behavioral or attitudinal responses, and on their viable effectiveness in organizations. Some studies claim that computer-mediated communication(CMC) is task-oriented but not suitable for emotional expression since it hinders close interpersonal interaction. On the other hand, some studies argue that individuals are able to develop interpersonal relationships more effectively in a CMC environment than in an FtF-environment. Due to the different perspectives, a theoretical gap exists, and it leads to the inconsistent research findings. The purpose of this paper is to combine the two different perspectives into single unified model, thereby providing a more realistic and comprehensive understanding about virtual collaboration. The present study here sought to answers the following questions with organizational communication perspective: What are the major components of virtual collaboration? What factors affect the performance of virtual collaboration? And what kind of managerial efforts should organization make in order to facilitate CMC media effectiveness in virtual collaboration? Although there is a certain belief that new media, namely technology-mediated communication support would create new opportunities, the problem of "how" or "why" has been an important question that is still not fully addressed. In this regards, we collectively reexamined previous literatures with major issues which are still controversial and integrated various theoretical activity within computer-mediated communication domain: task-oriented approach, socio-emotional approach, and evolutionary psychological approach. Our first contribution is to develop a framework for virtual collaboration by combining two different perspectives into a single unified model, providing a more realistic and comprehensive understanding. The second main contribution is the joint modeling of both social presence and cognitive effort, and the effects on two distinct but important communication outcomes(i.e., take performance and relational development). We tested the research hypotheses which were developed based on the various CMC theories using data gathered through a self-administered mail survey of 127 individuals of 69 virtual workgroups. The proposed model was supported, providing preliminary evidence that the tension between two opposite view should be integrated. The results show that the individual's psychological processes(social presence and cognitive effort) in a virtual environment significantly mediated the effect of CMC inputs (media richness, user adaptation, and shared contest) on the CMC outputs (task performance and relational development). Furthermore, this study shows that the lack of perceived media richness of CMC media can be complemented by user adaptation and shared context. Based on the results, we discuss how communication system should be designed and implemented so as to promote virtual interaction as well as how a virtual workgroup should be composed to complement the lack of media richness. A virtual collaboration using CMC media may create new value by overcoming the logistical constraints. On the other hand, it may also generate various managerial risks such as communicational depersonalization, process dissatisfaction, and low cohesion. Therefore, this study suggests that organization managers should carefully choose the CMC mediums and monitor individual member's cognitive and affective psychological processes during virtual collaboration to reduce potential risks in virtual collaboration.

• The Journal of the Korean Society for Microbiology
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• v.35 no.3
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• pp.263-271
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• 2000

A clinical isolate of Klebsiella pneumoniae K7746 produced the extended-spectrum ${\beta}$-lactamase (ESBL) SHV-12. A 6.6 kb BamHI fragment containing the $bla_{SHV-12}$ gene of K7746 strain was cloned into pCRScriptCAM vector resulting in the recombinant plasmid p7746-Cl. The restriction map of 3.6 kb inserted DNA and sequences immediately surrounding $bla_{SHV-12}$ of p7746-C1 were homologous to plasmid pMPA2a carrying $bla_{SHV-2a}$. In addition, both $bla_{SHV-12}$ and $bla_{SHV-2a}$ were expressed from a common hybrid promoter made of the -35 region derived from the left inverted repeat of IS26 and the -10 region from the $bla_{SHV}$ promoter itself. The results indicate that $bla_{SHV-12}$ and $bla_{SHV-2a}$ may have evolved from a common ancestor in the sequential order of $bla_{SHV-2a}$ first, followed by $bla_{SHV-12}$. Furthermore, by the PCR mapping method using primers corresponding to the IS26 and $bla_{SHV}$, the association between IS26 and $bla_{SHV}$ was studied in 12 clinical isolates carrying $bla_{SHV-2a}$, 27 clinical isolates carrying $bla_{SHV-12}$, and 5 reference strains carrying $bla_{SHV-1}$ to $bla_{SHV-5}$. All 39 strains carrying $bla_{SHV-2a}$ or $bla_{SHV-12}$ were positive by the PCR, providing confirmative evidence that IS26 has been involved in the evolution and dissemination of $bla_{SHV-2a}$ and $bla_{SHV-12}$. But 5 reference strains carrying $bla_{SHV-1}$ to $bla_{SHV-5}$ were negative by the PCR. Therefore, we concluded that the molecular evolutionary pathway of $bla_{SHV-2a}$ and $bla_{SHV-12}$ may be different from that of other $bla_{SHV-ESBL}$, e.g., $bla_{SHV-2}$, $bla_{SHV-3}$, $bla_{SHV-4}$, and $bla_{SHV-5}$.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.912-919
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• 2017

Objective: Identification of the candidate genes that play key roles in phenotypic variations can provide new information about evolution and positive selection. Interleukin (IL)-32 is involved in many biological processes, however, its role for the immune response against various diseases in mammals is poorly understood. Therefore, the current investigation was performed for the better understanding of the molecular evolution and the positive selection of single nucleotide polymorphisms in IL-32 gene. Methods: By using fixation index ($F_{ST}$) based method, IL-32 (9375) gene was found to be outlier and under significant positive selection with the provisional combined allocation of mean heterozygosity and $F_{ST}$. Using nucleotide sequences of 11 mammalian species from National Center for Biotechnology Information database, the evolutionary selection of IL-32 gene was determined using Maximum likelihood model method, through four models (M1a, M2a, M7, and M8) in Codeml program of phylogenetic analysis by maximum liklihood. Results: IL-32 is detected under positive selection using the $F_{ST}$ simulations method. The phylogenetic tree revealed that goat IL-32 was in close resemblance with sheep IL-32. The coding nucleotide sequences were compared among 11 species and it was found that the goat IL-32 gene shared identity with sheep (96.54%), bison (91.97%), camel (58.39%), cat (56.59%), buffalo (56.50%), human (56.13%), dog (50.97%), horse (54.04%), and rabbit (53.41%) respectively. Conclusion: This study provides evidence for IL-32 gene as under significant positive selection in goat.

• Journal of Astronomy and Space Sciences
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• v.29 no.2
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• pp.151-161
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• 2012

An intensive analysis of 148 timings of V700 Cyg was performed, including our new timings and 59 timings calculated from the super wide angle search for planets (SWASP) observations, and the dynamical evidence of the W UMa W subtype binary was examined. It was found that the orbital period of the system has varied over approximately $66^y$ in two complicated cyclical components superposed on a weak upward parabolic path. The orbital period secularly increased at a rate of $+8.7({\pm}3.4){\times}10^{-9}$ day/year, which is one order of magnitude lower than those obtained by previous investigators. The small secular period increase is interpreted as a combination of both angular momentum loss (due to magnetic braking) and mass-transfer from the less massive component to the more massive component. One cyclical component had a $20.^y3$ period with an amplitude of $0.^d0037$, and the other had a $62.^y8$ period with an amplitude of $0.^d0258$. The components had an approximate 1:3 relation between their periods and a 1:7 ratio between their amplitudes. Two plausible mechanisms (i.e., the light-time effects [LTEs] caused by the presence of additional bodies and the Applegate model) were considered as possible explanations for the cyclical components. Based on the LTE interpretation, the minimum masses of 0.29 $M_{\odot}$ for the shorter period and 0.50 $M_{\odot}$ for the longer one were calculated. The total light contributions were within 5%, which was in agreement with the 3% third-light obtained from the light curve synthesis performed by Yang & Dai (2009). The Applegate model parameters show that the root mean square luminosity variations (relative to the luminosities of the eclipsing components) are 3 times smaller than the nominal value (${\Delta}L/L_{p,s}{\approx}0.1$), indicating that the variations are hardly detectable from the light curves. Presently, the LTE interpretation (due to the third and fourth stars) is preferred as the possible cause of the two cycling period changes. A possible evolutionary implication for the V700 Cyg system is discussed.

• Plant Biotechnology Reports
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• v.5 no.4
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• pp.331-344
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• 2011

The well-conserved NBS domain of resistance (R) genes cloned from many plants allows the use of a PCR-based approach to isolate resistance gene analogs (RGAs). In this study, we isolated an RGA (CapRGC) from Capsicum annuum "CM334" using a PCR-based approach. This sequence encodes a protein with very high similarity to Rx genes, the Potato Virus X (PVX) R genes from potato. An evolutionary analysis of the CapRGC gene and its homologs retrieved by an extensive search of a Solanaceae database provided evidence that Rx-like genes (eight ESTs or genes that show very high similarity to Rx) appear to have diverged from R1 [an NBS-LRR R gene against late blight (Phytophthora infestans) from potato]-like genes. Structural comparison of the NBS domains of all the homologs in Solanaceae revealed that one novel motif, 14, is specific to the Rx-like genes, and also indicated that several other novel motifs are characteristic of the R1-like genes. Our results suggest that Rx-like genes are ancient but conserved. Furthermore, the novel conserved motifs can provide a basis for biochemical structural. function analysis and be used for degenerate primer design for the isolation of Rx-like sequences in other plant species. Comparative mapping study revealed that the position of CapRGC is syntenic to the locations of Rx and its homolog genes in the potato and tomato, but cosegregation analysis showed that CapRGC may not be the R gene against PVX in pepper. Our results confirm previous observations that the specificity of R genes is not conserved, while the structure and function of R genes are conserved. It appears that CapRGC may function as a resistance gene to another pathogen, such as the nematode to which the structure of CapRGC is most similar.

• Journal of Life Science
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• v.23 no.2
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• pp.324-331
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• 2013

The addition and removal of N-acetylglucosamine (GlcNAc) molecules on serine or threonine residues of a protein is called O-GlcNAcylation. This post-translational modification occurs on both cytoplasmic and nuclear protein, and is fast and reversible as comparable to phosphorylation. In contrast to the phospho-signaling cycles, this emerging moon-lightening signaling is cycled by only two enzymes, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). The simple machinery is a good evolutionary adaptation of a cell for quick accommodation to continuously fluctuating intra- and extracellular microenvironments. Rather than "switching" on or off a specific proteins - this would be done by phosphorylation where numerous specific kinases and phosphatases are involved - O-GlcNAcylation would play a "rheostat" which would be much more delicately increase or decrease the efficacy of signal transductions in response to cellular nutrient and stress conditions. Interestingly, recent evidence indicates that O-GlcNAc is further modified by phosphorylation. The O-GlcNAc-P will upgrade the modulation efficiency of cellular processes to continuous 'analogue' level. So far, only one protein AP180 was reported to have O-GlcNAc-P on Thr310. But, proteomic data from our laboratory indicate that there are multiple O-GlcNAc-P proteins, constituting "O-GlcNAc-P'om". This will focus on the possibility of existence of "O-GlcNAc-P'om".

• Anatomy & Biological Anthropology
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• v.31 no.4
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• pp.105-119
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• 2018

Archaeogenetics is an academic discipline that aims to establish scientific facts of human history by integrating ancient DNA analyses with archaeological and anthropological evidence. After ancient DNA research was initiated about 30 years ago, it has been innovated so rapidly that the range of analysis has been extended toward the whole genome sequence of ancient genomes in recent 10 years. By this development, researchers have been able to study in detail the origins and migration patterns of hominin species and ancient human populations by approaches of evolutionary genetics. This study has reviewed main principles of the archaeogenetic analysis and the current trends of ancient genome studies with recent achievements. While sampling techniques and statistical analyses have been improved, typical research methods have been established by the findings on hominins and ancient western Eurasia populations. Recently, archaeogenecists have been applying the methods to studying those in other geographical areas. Nonetheless, there is still the lack of ancient genome research about populations in Eastern Asia including the Korean peninsula. This review ultimately aims to predict possibilities and promise of future ancient genome studies of ancient Korean populations.