• Title/Summary/Keyword: Evolutionary Process

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What Characteristics Do Preservice Teachers Show During Trilobite Classification Activities? (예비교사들은 삼엽충 분류활동 중에 어떤 특성을 보이는가?)

  • Lim, Sungman
    • Journal of the Korean Society of Earth Science Education
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    • v.12 no.1
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    • pp.40-53
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    • 2019
  • This study was to analyze the inquiry characteristics of preservice teachers as they classify trilobites. For the study, 70 preservice teachers attending teacher training university participated. The classification tasks used in the study were 9 photos of trilobite fossils. The preservice teachers' inquiry activity was to classify the evolutionary processes of trilobites after observing trilobite fossils by group and then to construct a phylogenetic tree. The results of the study are as follows. First, preservice teachers observed the external features of the trilobites and constructed systematic classification results based on their observed contents. Second, preservice teachers classified trilobites using various classification criteria. Third, the phylogenetic tree of preservice teachers and the phylogenetic tree of scientists were very similar. The preservice teachers constructed a sphylogenetic tree based on the observation and inference of the change from a simple form to a complex form, which is a general evolution process of the trilobite fossil claimed by scientists. These results suggest that group-based inquiry activities with sufficient time are very effective and that the experience of inquiry activities is very important for preservice teachers.

Optimal Design of a Hybrid Structural Control System using a Self-Adaptive Harmony Search Algorithm (자가적응 화음탐색 알고리즘을 이용한 복합형 최적 구조제어 시스템 설계)

  • Park, Wonsuk
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.31 no.6
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    • pp.301-308
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    • 2018
  • This paper presents an optimal design method of a hybrid structural control system considering multi-hazard. Unlike a typical structural control system in which one system is designed for one specific type of hazard, a simultaneous optimal design method for both active and passive control systems is proposed for the mitigation of seismic and wind induced vibration responses of structures. As a numerical example, an optimal design problem is illustrated for a hybrid mass damper(HMD) and 30 viscous dampers which are installed on a 30 story building structure. In order to solve the optimization problem, a self-adaptive Harmony Search(HS) algorithm is adopted. Harmony Search algorithm is one of the meta-heuristic evolutionary methods for the global optimization, which mimics the human player's tuning process of musical instruments. A self-adaptive, dynamic parameter adjustment algorithm is also utilized for the purpose of broad search and fast convergence. The optimization results shows that the performance and effectiveness of the proposed system is superior with respect to a reference hybrid system in which the active and passive systems are independently optimized.

Phylogenetic analysis of Neottia japonica (Orchidaceae) based on ITS and matK regions

  • SO, Ji-Hyeon;LEE, Nam-Sook
    • Korean Journal of Plant Taxonomy
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    • v.50 no.4
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    • pp.385-394
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    • 2020
  • To elucidate the molecular phylogeny of Neottia japonica, which is a terrestrial orchid distributed in East Asia, the internal transcribed spacer (ITS) of nuclear DNA and the matK of chloroplast DNA were used. A total 22 species of 69 accessions for ITS and 21 species of 114 accessions for matK phylogeny were analyzed with the maximum parsimony and Bayesian methods. In addition, we sought to establish a correlation between the distribution, morphology of the auricles and genetic association of N. japonica with phylogenetic data. The phylogenetic results suggest that N. japonica is monophyletic and a sister to N. suzukii in terms of the ITS phylogeny, while it is paraphyletic with N. suzukii in terms of the matK phylogeny. N. japonica and N. suzukii show similar morphologies of the lip and column, they both flower in April, and they are both distributed sympatrically in Taiwan. Therefore, it appears to be clear that N. japonica and N. suzukii are close taxa within Neottia, although there is incongruence between the nrDNA and cpDNA phylogenies of N. japonica. The incongruence between the two datasets may have various causes, meaning that further studies are needed to confirm the evolutionary process of N. japonica. The phylogenetic status of N. kiusiana, which was not included in previous studies, was as a sister to N. nidus-avis. Meanwhile, the ITS and matK phylogenies are unsuitable for identifying genetic associations with the characteristic of auricles. The phylogenetic topologies of Korean, Taiwanese and mainland Chinese individuals suggest that the populations of N. japonica in Korea originated from China's mainland and island areas. The characterization of regional gene differences could provide useful preliminary data for future studies.

Caution and Curation for Complete Mitochondrial Genome from Next-Generation Sequencing: A Case Study from Dermatobranchus otome (Gastropoda, Nudibranchia)

  • Do, Thinh Dinh;Choi, Yisoo;Jung, Dae-Wui;Kim, Chang-Bae
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.4
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    • pp.336-346
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    • 2020
  • Mitochondrial genome is an important molecule for systematic and evolutionary studies in metazoans. The development of next-generation sequencing (NGS) technique has rapidly increased the number of mitogenome sequences. The process of generating mitochondrial genome based on NGS includes different steps, from DNA preparation, sequencing, assembly, and annotation. Despite the effort to improve sequencing, assembly, and annotation methods of mitogenome, the low quality and/or quantity sequence in the final map can still be generated through the work. Therefore, it is necessary to check and curate mitochondrial genome sequence after annotation for proofreading and feedback. In this study, we introduce the pipeline for sequencing and curation for mitogenome based on NGS. For this purpose, two mitogenome sequences of Dermatobranchus otome were sequenced by Illumina Miseq system with different amount of raw read data. Generated reads were targeted for assembly and annotation with commonly used programs. As abnormal repeat regions present in the mitogenomes after annotation, primers covering these regions were designed and conventional PCR followed by Sanger sequencing were performed to curate the mitogenome sequences. The obtained sequences were used to replace the abnormal region. Following the replacement, each mitochondrial genome was compared with the other as well as the sequences of close species available on the Genbank for confirmation. After curation, two mitogenomes of D. otome showed a typically circular molecule with 14,559 bp in size and contained 13 protein-coding genes, 22 tRNA genes, two rRNA genes. The phylogenetic tree revealed a close relationship between D. otome and Tritonia diomea. The finding of this study indicated the importance of caution and curation for the generation of mitogenome from NGS.

Web-based Personal Dose Management System for Data Recording on Dosimeter Usage: A Case of Tanzania Atomic Energy Commission

  • Mseke, Angela;Ngatunga, John Ben;Sam, Anael;Nyambo, Devotha G.
    • International Journal of Computer Science & Network Security
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    • v.22 no.2
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    • pp.15-22
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    • 2022
  • Modern technology drives the world, increasing performance while reducing labor and time expenses. Tanzania Atomic Energy Commission (TAEC) tracks employee's levels of exposure to radiation sources using dosimeters. According to legal compliance, workers wear dosimeters for three months and one month at the workplace. However, TAEC has problems in tracking, issuing and returning dosimeters because the existing tracking is done manually. The study intended to develop a Personal Dose Management System (PDMS) that processes and manages the data collected by dosimeters for easy and accurate records. During the requirements elicitation process, the study looked at the existing system. PDMS' requirement gathering included document reviews, user interviews, and focused group discussions. Development and testing of the system were implemented by applying the evolutionary prototyping technique. The system provides a login interface for system administrators, radiation officers, and Occupational Exposed Workers. The PDMS grants TAEC Staff access to monitor individual exposed workers, prints individual and institutional reports and manages workers' information. The system reminds the users when to return dosimeters to TAEC, generate reports, and facilitates dispatching and receiving dosimeters effectively. PDMS increases efficiency and effectiveness while minimizing workload, paperwork, and inaccurate records. Therefore, based on the results obtained from the system, it is recommended to use the system to improve dosimeter data management at the institution.

Complete genome sequencing and comparative genomic analysis of Lactobacillus acidophilus C5 as a potential canine probiotics

  • Son, Seungwoo;Lee, Raham;Park, Seung-Moon;Lee, Sung Ho;Lee, Hak-Kyo;Kim, Yangseon;Shin, Donghyun
    • Journal of Animal Science and Technology
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    • v.63 no.6
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    • pp.1411-1422
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    • 2021
  • Lactobacillus acidophilus is a gram-positive, microaerophilic, and acidophilic bacterial species. L. acidophilus strains in the gastrointestinal tracts of humans and other animals have been profiled, but strains found in the canine gut have not been studied yet. Our study helps in understanding the genetic features of the L. acidophilus C5 strain found in the canine gut, determining its adaptive features evolved to survive in the canine gut environment, and in elucidating its probiotic functions. To examine the canine L. acidophilus C5 genome, we isolated the C5 strain from a Korean dog and sequenced it using PacBio SMRT sequencing technology. A comparative genomic approach was used to assess genetic relationships between C5 and six other strains and study the distinguishing features related to different hosts. We found that most genes in the C5 strain were related to carbohydrate transport and metabolism. The pan-genome of seven L. acidophilus strains contained 2,254 gene families, and the core genome contained 1,726 gene families. The phylogenetic tree of the core genes in the canine L. acidophilus C5 strain was very close to that of two strains (DSM20079 and NCFM) from humans. We identified 30 evolutionarily accelerated genes in the L. acidophilus C5 strain in the ratio of non-synonymous to synonymous substitutions (dN/dS) analysis. Five of these thirty genes were associated with carbohydrate transport and metabolism. This study provides insights into genetic features and adaptations of the L. acidophilus C5 strain to survive the canine intestinal environment. It also suggests that the evolution of the L. acidophilus genome is closely related to the host's evolutionary adaptation process.

In silico genome wide identification and expression analysis of the WUSCHEL-related homeobox gene family in Medicago sativa

  • Yang, Tianhui;Gao, Ting;Wang, Chuang;Wang, Xiaochun;Chen, Caijin;Tian, Mei;Yang, Weidi
    • Genomics & Informatics
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    • v.20 no.2
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    • pp.19.1-19.15
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    • 2022
  • Alfalfa (Medicago sativa) is an important food and feed crop which rich in mineral sources. The WUSCHEL-related homeobox (WOX) gene family plays important roles in plant development and identification of putative gene families, their structure, and potential functions is a primary step for not only understanding the genetic mechanisms behind various biological process but also for genetic improvement. A variety of computational tools, including MAFFT, HMMER, hidden Markov models, Pfam, SMART, MEGA, ProtTest, BLASTn, and BRAD, among others, were used. We identified 34 MsWOX genes based on a systematic analysis of the alfalfa plant genome spread in eight chromosomes. This is an expansion of the gene family which we attribute to observed chromosomal duplications. Sequence alignment analysis revealed 61 conserved proteins containing a homeodomain. Phylogenetic study sung reveal five evolutionary clades with 15 motif distributions. Gene structure analysis reveals various exon, intron, and untranslated structures which are consistent in genes from similar clades. Functional analysis prediction of promoter regions reveals various transcription binding sites containing key growth, development, and stress-responsive transcription factor families such as MYB, ERF, AP2, and NAC which are spread across the genes. Most of the genes are predicted to be in the nucleus. Also, there are duplication events in some genes which explain the expansion of the family. The present research provides a clue on the potential roles of MsWOX family genes that will be useful for further understanding their functional roles in alfalfa plants.

An Agent Based Simulation Model for the Analysis of Team Formation (팀 결성 분석을 위한 행위자 기반 시뮬레이션 모형)

  • Yee, Soung-Ryong
    • Journal of the Korea Society for Simulation
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    • v.19 no.4
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    • pp.169-178
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    • 2010
  • Agent based simulation is an approach for the analysis of a system's long term behavior where the entities in the system behave independently by their own judgement and memory, but influence each other to cope with given environment. In this paper we developed an agent based simulation model for the analysis of behavioral mechanism of team formation. In the process of team formation members' mutual preference is an important factor although each member can join up with one's own will. Also a team performance can vary by the member's own experience. We implemented the developed model using Netlogo 4.1, and verified the model by simulation. From the simulation results we found that the model successfully performed necessary functions using behavioral rules, judgments, and evolutionary processes by memory. As a further study we will be able to apply the model for analyzing various ecological behavior of team formation.

Software Industry and Patents : Legal Evolution and Economic Arguments (소프트웨어 산업과 특허: 법적 진화와 경제적 쟁점)

  • Hahn, Yoon-Hwan
    • Journal of Korea Society of Industrial Information Systems
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    • v.15 no.2
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    • pp.99-113
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    • 2010
  • Beyond the rapid normalization process of patents in software industry, complex legal evolution and rigorous economic arguments underlie the crucial environmental transformation of the industry. In this article, we trace the evolutionary history for the theory and practice of patents in software industry from both legal and economic perspectives. First, we study the legal disputes and cases in light with the underpinnings of patent policy transformation, and then delve into the economic backrounds of the pros and cons for software patents, with special focus on the generic economic peculiarities of software industry. The fact that historical and practical policy and law in Korea have been largely affected from those of USA, and relative deficiency in the law, economics and management literature are the main motivation of the study, and we hope this study to contribute to the decision making of policymakers as well as law and business practitioners.

Tracing history of the episodic accretion process in protostars

  • Kim, Jaeyeong;Lee, Jeong-Eun;Kim, Chul-Hwan;Hsieh, Tien-Hao;Yang, Yao-Lun;Murillo, Nadia;Aikawa, Yuri;Jeong, Woong-Seob
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.66.3-67
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    • 2021
  • Low-mass stars form by the gravitational collapse of dense molecular cores. Observations and theories of low-mass protostars both suggest that accretion bursts happen in timescales of ~100 years with high accretion rates, so called episodic accretion. One mechanism that triggers accretion bursts is infalling fragments from the outer disk. Such fragmentation happens when the disk is massive enough, preferentially activated during the embedded phase of star formation (Class 0 and I). Most observations and models focus on the gas structure of the protostars undergoing episodic accretion. However, the dust and ice composition are poorly understood, but crucial to the chemical evolution through thermal and energetic processing via accretion burst. During the burst phase, the surrounding material is heated up, and the chemical compositions of gas and ice in the disk and envelope are altered by sublimation of icy molecules from grain surfaces. Such alterations leave imprints in the ice composition even when the temperature returns to the pre-burst level. Thus, chemical compositions of gas and ice retain the history of past bursts. Infrared spectral observations of the Spitzer and AKARI revealed a signature caused by substantial heating, toward many embedded protostars at the quiescent phase. We present the AKARI IRC 2.5-5.0 ㎛ spectra for embedded protostars to trace down the characteristics of accretion burst across the evolutionary stages. The ice compositions obtained from the absorption features therein are used as a clock to measure the timescale after the burst event, comparing the analyses of the gas component that traced the burst frequency using the different refreeze-out timescales. We discuss ice abundances, whose chemical change has been carved in the icy mantle, during the different timescales after the burst ends.

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