• Title/Summary/Keyword: four classes

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Comparison of Microscopy and Pigment Analysis for Determination of Phytoplankton Community Composition: Application of CHEMTAX Program (식물플랑크톤 군집조성 파악을 위한 현미경관찰법과 지표색소분석법 비교 연구: CHEMTAX 프로그램 활용)

  • Kim, Dokyun;Choi, Jisoo;Oh, Hye-Ji;Chang, Kwang-Hyeon;Choi, Kwangsoon;Shin, Kyung-Hoon
    • Korean Journal of Ecology and Environment
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    • v.54 no.4
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    • pp.303-314
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    • 2021
  • To understand how to efficiently observe the biomass and community of phytoplankton, phytoplankton sampling was carried out from June to October 2019 at the Yeongju dam sediment control reservoir(YJ) and Bohyeonsan dam reservoir(BH1 and BH2). The results derived from microscopic observation, such as the conventional phytoplankton qualitative/quantitative analysis, and from the CHEMTAX method based on the pigments, were compared. The relative contribution of phytoplankton, calculated by the microscopy and CHEMTAX methods, showed a significant difference in all four classes: cryptophyta, chlorophyta, cyanobacteria, and diatoms. In addition, the correlation between the two observation methods was poor. This might be caused by methodological differences in microscopy that do not consider the varying cell sizes among phytoplankton species. In this study, by converting the cells into carbon, the slope between both carbon biomasses based on microscopy and CHEMTAX was improved close to the 1 : 1 line, and the y-intercept was closer to 0 for cryptophyta and diatoms. For cyanobacteria, the slope increased, the y-intercept decreased, and the plot approached 1 : 1 although the correlation coefficients were not improved in all classes. The present study suggests that application of CHEMTAX based on pigment analysis could be a possible approach to efficiently determine the relative carbon proportions of individual classes of phytoplankton community composition.

Context-Based Design and Its Application Effects in Science Classes (맥락을 중요시하는 과학 수업 전략의 개발 및 적용)

  • Jung, Suk-Jin;Shin, Young-Joon
    • Journal of Korean Elementary Science Education
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    • v.43 no.1
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    • pp.48-63
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    • 2024
  • This study aims to develop a class procedure for the application of classrooms that value context and to conduct science classes using this procedure to examine the effects. Among various contexts related to scientific knowledge, the study develops a teaching procedure for designing classes that focus on the contexts of discovery and real life. After verifying the content validity of the context-based design and the program to which it was applied, a class was conducted, and the responses of the children were checked. The final draft of the lesson design completed after revision and supplementation is as follows: context-based design was presented in four stages, namely, presenting, exploring the context, adapting the context, and organizing (share and synthesizing; PEAS). The goal is to enable people to experience the overall flow of scientific knowledge instead of focusing on the acquisition of fragmentary knowledge by covering a wide range of topics from the social and historical contexts in which scientific knowledge was created to its use in real life. To aid in understanding the newly proposed class procedure and verifying its effectiveness, we developed a program by selecting the "My Fun Exploration," 2. Biology and Environment unit of the second semester of the fifth grade. The result indicated that the elementary science program that applied the context-centered design effectively improved the self-directed learning ability of students. In addition, the effect was especially notable in terms of intrinsic motivation. As the students experienced the contexts of discovery and real life related to scientific knowledge, they developed the desire to actively participate in science learning. As this becomes an essential condition for deriving active learning effects, a virtuous cycle in which meaningful learning can occur has been created. Based on the implications, developing programs that apply context-based design to various areas and contents will be possible.

Dechlorination of Individual Congeners in Aroclor 1248 as Enhanced by Chlorobenzoates, Chlorophenols, and Chlorobenzenes

  • Kim, Jong-Seol;Cho, Young-Cheol;Frohnhoefer, Robert C.;Rhee, G-Yull
    • Journal of Microbiology and Biotechnology
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    • v.18 no.10
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    • pp.1701-1708
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    • 2008
  • Previous investigations showed that three classes of haloaromatic compounds (HACs; chlorobenzoates, chlorophenols, and chlorobenzenes) enhanced the reductive dechlorination of Aroclor 1248, judging from the overall extent of reduction in CI atoms on the biphenyl. In the present study, we further investigated the kind of polychlorinated biphenyl (PCB) congeners involved in the enhanced dechlorination by four isomers belonging to each class (2,3-, 2,5-, 2,3,5-, and 2,4,6-chlorobenzoates; 2,3-, 3,4-, 2,5-, and 2,3,6-chlorophenols; and 1,2-, 1,2,3-, 1,2,4-, and penta-chlorobenzenes). Although the PCB congeners involved in the enhanced dechlorination varied with the HACs, the enhancement primarily involved para-dechlorination of the same congeners (2,3,4'-, 2,3,4,2'-plus 2,3,6,4'-, 2,5,3',4'- plus 2,4,5,2',6'-, and 2,3,6,2',4'-chlorobiphenyls), regardless of the HACs. These congeners are known to have low threshold concentrations for dechlorination. To a lesser extent, the enhancement also involved meta dechlorination of certain congeners with high threshold concentrations. There was no or less accumulation of 2,4,4'- and 2,5,4'-chlorobiphenyls as final products under HAC amendment. Although the dechlorination products varied, the accumulation of ortho-substituted congeners, 2-, 2,2'-, and 2,6-chlorobiphenyls, was significantly higher with the HACs, indicating a more complete dechlorination of the highly chlorinated congeners. Therefore, the present results suggest that the enhanced dechlorination under HAC enrichment is carried out through multiple pathways, some of which may be universal, regardless of the kind of HACs, whereas others may be HAC-specific.

Classification of Mental States Based on Spatiospectral Patterns of Brain Electrical Activity

  • Hwang, Han-Jeong;Lim, Jeong-Hwan;Im, Chang-Hwan
    • Journal of Biomedical Engineering Research
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    • v.33 no.1
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    • pp.15-24
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    • 2012
  • Classification of human thought is an emerging research field that may allow us to understand human brain functions and further develop advanced brain-computer interface (BCI) systems. In the present study, we introduce a new approach to classify various mental states from noninvasive electrophysiological recordings of human brain activity. We utilized the full spatial and spectral information contained in the electroencephalography (EEG) signals recorded while a subject is performing a specific mental task. For this, the EEG data were converted into a 2D spatiospectral pattern map, of which each element was filled with 1, 0, and -1 reflecting the degrees of event-related synchronization (ERS) and event-related desynchronization (ERD). We evaluated the similarity between a current (input) 2D pattern map and the template pattern maps (database), by taking the inner-product of pattern matrices. Then, the current 2D pattern map was assigned to a class that demonstrated the highest similarity value. For the verification of our approach, eight participants took part in the present study; their EEG data were recorded while they performed four different cognitive imagery tasks. Consistent ERS/ERD patterns were observed more frequently between trials in the same class than those in different classes, indicating that these spatiospectral pattern maps could be used to classify different mental states. The classification accuracy was evaluated for each participant from both the proposed approach and a conventional mental state classification method based on the inter-hemispheric spectral power asymmetry, using the leave-one-out cross-validation (LOOCV). An average accuracy of 68.13% (${\pm}9.64%$) was attained for the proposed method; whereas an average accuracy of 57% (${\pm}5.68%$) was attained for the conventional method (significance was assessed by the one-tail paired $t$-test, $p$ < 0.01), showing that the proposed simple classification approach might be one of the promising methods in discriminating various mental states.

Members of Ectocarpus siliculosus F-box Family Are Subjected to Differential Selective Forces

  • Mahmood, Niaz;Moosa, Mahdi Muhammad;Matin, S. Abdul;Khan, Haseena
    • Interdisciplinary Bio Central
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    • v.4 no.1
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    • pp.1.1-1.7
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    • 2012
  • Background: The F-box proteins represent one of the largest families of proteins in eukaryotes. Apart from being a component of the ubiquitin (Ub)/26 S proteasome pathways, their regulatory roles in other cellular and developmental pathways have also been reported. One interesting feature of the genes encoding the proteins of this particular family is their variable selection patterns across different lineages. This resulted in the presence of lineage specific F-box proteins across different species. Findings: In this study, 48 non-redundant F-box proteins in E. siliculosus have been identified by a homology based approach and classified into three classes based on their variable C-terminal domains. A greater number of the F-box proteins have domains similar to the ones identified in other species. On the other hand, when the proteins having unknown or no C-terminal domain (as predicted by InterProScan) were analyzed, it was found that some of them have the polyglutamine repeats. To gain evolutionary insights on the genes encoding the F-box proteins, their selection patterns were analyzed and a strong positive selection was observed which indicated the adaptation potential of the members of this family. Moreover, four lineage specific F-box genes were found in E. siliculosus with no identified homolog in any other species. Conclusions: This study describes a genome wide in silico analysis of the F-box proteins in E. siliculosus which sheds light on their evolutionary patterns. The results presented in this study provide a strong foundation to select candidate sequences for future functional analysis.

Effect of Single Nucleotide Polymorphisms of Acetyl-CoA Carboxylase α(ACACA) Gene on Carcass Traits in Hanwoo (Korean Cattle)

  • Shin, Sung-Chul;Heo, Jae-Pil;Chung, Eui-Ryong
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.6
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    • pp.744-751
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    • 2011
  • Meat production and quality traits in beef cattle are largely affected by genetic factors. Acetyl-Coenzyme A carboxylase-${\alpha}$ (ACACA) plays a key role in the regulation and metabolism of fatty acid biosynthesis in mammalian animals. The gene encoding ACACA enzyme was chosen as a candidate gene for carcass and meat traits. In this study, we investigated effects of single nucleotide polymorphisms (SNPs) in the ACACA gene on beef carcass and meat traits in Hanwoo (Korean cattle) populations. We have sequenced a fragment of intron I region of the Hanwoo ACACA gene and identified two SNPs. Genotyping of the two SNP markers (g.2344T>C and g.2447C>A) was carried out using PCR-SSCP analysis in 309 Hanwoo steers to evaluate their association with carcass and meat production traits. The g.2344C SNP marker showed a significant increasing effect on LW (p = 0.009) and CW (p = 0.017). Animals with the CC genotype had higher CW and LW compared with TT and TC genotypes (p<0.05). The g.2447A SNP marker was associated with higher MC (p = 0.019). Animals with the AA genotype had higher MC than animals with CC and CA genotypes (p<0.05). Although the degree of linkage disequilibrium (LD) was not strong between g.2344T>C and g.2447C>A in the LD analysis, four major haplotype classes were formed with two SNP information within the ACACA gene. We constructed haplotypes using the HaploView software package program and analyzed association between haplotypes and carcass traits. The haplotype of ACACA gene significantly affected the LW (p = 0.027), CW (p = 0.041) and MC (p = 0.036). The effect of h1 haplotype on LW and CW was larger than that of h3 haplotype. Animals with the h1 haplotype also had greater MC than did animals with h2 haplotype. Consequently, the ACACA gene could be useful as a DNA marker for meat production traits such as carcass yield and meat contents in Hanwoo.

Regression Model for Estimating Biomass of Natural Pinus densifrola Forests in Northeast Area of Mt. Paekdu (백두산 동북부지역 소나무 천연림 biomass 추정모델)

  • 김영환;이돈구;맹헌우
    • Journal of Korea Foresty Energy
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    • v.17 no.1
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    • pp.23-29
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    • 1998
  • This study was carried out to develop the regression model for estimating biomass of natural Pinus densiflora forests by stand density in northeast Chinese area of Mt. Paekdu. Four allometric regression models(W=aD$^b$, W=a(D$^2$H)$^b$. logW=a+b$\cdot$ logD+cD and logW=a+b$\cdot$log(D$^2$H)+c(D$^2$H)) were used to estimate biomass for each of the tree components. The suitable regression model for estimating biomass of stem, bark and whole tree above ground was logW=a+b$\cdot$log(D$^2$H)+c(D$^2$H), and that for biomass of branch, needle and needle area, logW=a+b$\cdot$logD+cD for all of the stand density classes.

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Research on Classification of Human Emotions Using EEG Signal (뇌파신호를 이용한 감정분류 연구)

  • Zubair, Muhammad;Kim, Jinsul;Yoon, Changwoo
    • Journal of Digital Contents Society
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    • v.19 no.4
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    • pp.821-827
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    • 2018
  • Affective computing has gained increasing interest in the recent years with the development of potential applications in Human computer interaction (HCI) and healthcare. Although momentous research has been done on human emotion recognition, however, in comparison to speech and facial expression less attention has been paid to physiological signals. In this paper, Electroencephalogram (EEG) signals from different brain regions were investigated using modified wavelet energy features. For minimization of redundancy and maximization of relevancy among features, mRMR algorithm was deployed significantly. EEG recordings of a publically available "DEAP" database have been used to classify four classes of emotions with Multi class Support Vector Machine. The proposed approach shows significant performance compared to existing algorithms.

Comparing the Ethical Knowledge, Ethical Values and Class Satisfaction by Students' Cognitive Style to Develope the Convergent Nursing Ethic Class (융복합 간호윤리수업 개발을 위한 학생의 인지양식에 따른 윤리지식, 윤리적 가치관과 수업만족도 비교)

  • Jeong, Sun-Young;Kim, Chang-Hee
    • Journal of Digital Convergence
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    • v.13 no.11
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    • pp.205-216
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    • 2015
  • The purpose was to compare the ethical knowledge, values and class satisfaction by students' cognitive style to develop the convergent nursing ethic class considering cognitive style. Questionnaires were collected from 149 freshmen after 12 hours classes for four weeks from October 1st to 30th 2013. Group Embedded Figure Test was used as a cognitive style measurement tool. 62.4% of them were field-dependent. There was a significant difference in cognitive style and ethical knowledge according to high school division. The ethical value was different significantly according to the nursing science satisfaction. Class satisfaction was different significantly according to reason for applying to nursing and nursing science satisfaction. There were no significant differences in ethical knowledge and values by cognitive style. Class satisfaction was higher in field-dependent students. This conclusion will give baseline data to develop nursing education program based on cognitive style.

Is Sorting Hat in Harry Potter Identity Identifier for Adolescents?

  • Bahn, Geon Ho;Sun, Je Young Hannah;Hwangbo, Ram;Hong, Minha;Park, Jin Cheol;Cho, Seong Woo
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.28 no.1
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    • pp.38-43
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    • 2017
  • This study analyzes the role of the Sorting Hat in structuring the identity of the characters in the Harry Potter series written by J. K. Rowling. In the different stages of adolescence, one explores and re-establishes one's identity. One's sense of identity is determined by the commitments made regarding personal and social traits. However, it is difficult to establish a concrete identity formation process theory that is communicable to adolescents. In Harry Potter, the characters' identities are reflected upon the Sorting Hat and are continuously molded throughout the book. The Sorting Hat provides nurturing experiences based on temperament. Based primarily on their temperament, it sorts the students into four houses, each with their own distinct characteristics. Once sorted, the houses become the living and learning communities in which the students share the same dormitory and classes until their graduation. Within the community, the students seek connections, supportive relationships, and understanding within the group. The taking on of the group identity is an explanatory variable in the formation of individual identity. The Sorting Hat provides the students with stability and a safe boundary. After being sorted based on their temperament, the inexperienced and immature adolescents can explore different options under the guidance of the Hat before making a definite commitment. By presenting them with an appropriate environment (such as a mentor, friend, or family member), the Hat further shapes their identity and integrates the identity elements ascribed in the beginning. By providing experiences and interactions based on their unique temperament and environment, the Sorting Hat plays a crucial role in establishing the students' identities. The Sorting Hat can be an ideal model for finding one's identity during adolescence.