• 한국과학교육학회지
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• 제29권3호
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• pp.277-290
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• 2009

In the era of the outcome-based education, multiple-choice test has been widely employed owing to its efficiency that enables educators to evaluate a quantity of students with much objectiveness. However, the prevalent test has not been reconsidered enough to overcome its apparent shortcomings: examiners' effort for developing plausible and faultless distracters defending from every falsification, and students' random guessing on key choices. For alleviating such defects, tiered test as an experimental format of multiple-choice tests has been suggested in science education. Since there has not accumulated much study on the implementation of tiered tests, our research aim is set to construct a framework suggesting statistical indexes for rationally discerning tiered units that develop an effective tiered test. Graded both by our tiered-scoring and by the conventional partial-scoring, the preliminary tiered test in secondary physics attests the improvement in its discrimination and difficulty distribution. The findings reveal that the two indexes discern effective tiered items: discrimination increase (Ct-p) and difficulty decrease (Dp-t). Based on the index information, 4 heterogeneous tier types are recommended in the content of secondary physics: directional manipulation, repeated calculation, diverse explanation, and plural variables.

• 대한한의학방제학회지
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• 제16권1호
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• pp.65-78
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• 2008

Objectives : this study was to access the effect of Hyeonggaeyeongyotang water extracts, a polyherbal formula has been used as folk medicine, on the fertility and early embryonic development of male and female Wistar rats when administered by oral gavage. Methods : In male rats, Hyeonggaeyeongyotang extract were dosed 4 weeks before pairing and 2 weeks after mating including the mating periods up to termination after necropsy of the majority of the females. In female rats, they were dosed 2 weeks before pairing, and from Day 0 to Day 7 of gestation. This study was conducted in accordance with the recommendations of the KFDA Guideline [2005-60] for Detection of Toxicity to Reproduction for Medicinal Products. Results: 1. No Hyeonggaeyeongyotang extract treatment-related changes on the clinical signs and mortalities, the Food consumptions, the Body weights and gains were demonstrated in all dosed levels tested in this study except for 500ml/kg-dosing male group in which a significant(p<0.05) increase of body gains was detected during day 0-7 after dosing. 2. No Hyeonggaeyeongyotang extract treatment-related changes on the pre-coital intervals, the estrus cycles, the mating index, conception rate and fertility index were demonstrated in all dosed levels tested in this study. 3. No Hyeonggaeyeongyotang extract treatment-related gross findings on reproductive organs, the weights of reproductive organs, histopathological findings on reproductive organs, the corpora lutea number, implantation site number, live fetus number, number of resorpted embryo and pre-and post-implatation loss were demonstrated in all dosed levels tested in this study. Conclusions : Base on the results, it is considered that the NOAEL (No-Observed-Adverse-Effect Level) for fertility and early embryonic development toxicity of Hyeonggaeyeongyotang extract was under 2000ml/kg/day in Wistar male and female rats because there no treatment-related changes on the fertility and early embryonic developmental index were demonstrated in all dosed levels tested.

• Journal of Ecology and Environment
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• 제41권7호
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• pp.182-190
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• 2017

Background: Baekdudaegan was designated in 2005 as a protected area to prevent destruction and conserve. However, there are many disturbed and destroyed areas. The total disturbed area amounts to $25.9km^2$ (0.94%), including $13.4km^2$ (0.49%) in the core area and $12.5km^2$ (0.45%) in the buffer area. This study aims to classify the vegetation types established in the disturbed areas and diagnose the current conditions for ecological restoration in the forest ecosystem. Methods: We surveyed the vegetation in the disturbed areas of Daegwallyeong and Chupungryeong and the surrounding natural areas. The survey conducted from July to September 2015 targeted a total of 54 quadrats by Braun-Blanquet method (Daegwallyeong, 22; Chupungryeong, 32). We also investigated the height and coverage of each layer. We classified the vegetation types based on the field data and analyzed the ratio of life form and the exotic plants, species richness, and vegetation index (Hcl). The Normalized Difference Vegetation Index (NDVI) was calculated from rapideye satellite imagery in 2014 and 2015. Results: Vegetation types were classified into 11 groups according to the criteria that included successional sere or plantation at first, followed by developmental stage and origins. As a result of the analysis of the survey data, species richness, vegetation index (Hcl), ratio of tree plants, and the NDVI tended to increase, while the ratio of the exotic plants tended to decrease with the time since disturbance. These indicators had the classified values according to the vegetation types with time since the disturbance. Conclusions: These indicators can be effectively used to diagnose the conditions of the present vegetation in the disturbed area of the Baekdudaegan area. In addition, the NDVI might be effective for the diagnosis of the disturbed status instead of the human efforts based on the higher spatial resolution of satellite imagery. Appropriate diagnosis of the disturbed forests in the Baekdudaegan area considering the established vegetation types is essential for the elaboration of restoration plans. In addition, restoration target and level should be different according to the disturbed status of restoration site.

• 한국패류학회지
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• 제20권1호
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• pp.75-84
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• 2004

Reproductive cycle, the condition index, sex ratio of the Pacific oysters, Crassostrea gigas were investigated by histological and morphometric data. The specimens were collected in the two oyster farms of Geoje and Namhae, Gyeongsangnam-do, Korea, from November 1995 to October 1996. Growth of shell length in two regions was similar, but growth of total weight of the oyster in Namhae was faster than that in Geoje oyster farm. The spawning periods in female and male clams were from July to October in Geoje and from June to October in Namhae oyster farm. Ripe oocytes were approximately 50 m in diameter. The reproductive cycle of in females and males in Geoje and Namhae oyster farms can be divided into five successive stages: early developing, late developing, ripe, partially spawned and spent/inactive. Monthly changes in gonad developmental phases showed somewhat different patterns between female and male clams except for the spawning period. On the whole, however, monthly changes in the gonad developmental phases showed a similar pattern in the same sex. The sex ratios of females to males in Geoje and Namhae oyster farms were not significantly different from a 1:1 sex ratio ($x^2$ = 0.55 (p > 0.05) in Geoje and $x^2$ = 0.27 ( p > 0.05) in Namhae). Artificial induction of maturation by heating of adult oysters (two-year-old) was investigated from 17 January to 18 March in 1996. Maturity at the fixed water temperature group of $20^{\circ}C$ was 80%, it showed the highest maturity of experimental groups cultured for five weeks. The survival (%) of Crassostrea gigas in the raised water temperature experimental groups (15, 20, $25^{\circ}C$) were over 98.5%, as similar to the control group (100%). But, the survival of C. gigas in the fixed water temperature experimental groups (15, 20, 25, $30^{\circ}C$) were decreased with the increase of the water temperatures. In the fixed water temperature experimental group of $30^{\circ}C$, the survival was 51.1%. Base on these results, the fixed water temperature of $20^{\circ}C$ was the best condition for artificial induction of sexual maturation.

• Clinical and Experimental Pediatrics
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• 제45권10호
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• pp.1199-1203
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• 2002

목 적: 언어발달장애를 주소로 내원하는 소아들을 대상으로 청성뇌간반응(ABR)을 선별검사로 시행함으로써 그 원인을 조기 발견하고 조기 치료함으로써 이들의 장애를 최소화하고 언어발달 과정에 도움을 주고자 본 연구를 시행하였다. 방 법 : 1999년 1월부터 2001년 12월까지 3년 동안 경북대학교병원 소아과에 언어발달장애를 주소로 내원한 18개월 이상 소아 139례를 대상으로 하여 청성뇌간반응(ABR)을 시행하였으며 이들의 임상진단과 ABR 이상에 따라 분류하였다. 결 과 : 전체 139례 중 ABR 검사상 이상소견을 보인 환아는 15례(10.8%)였으며 전반적 발달장애 7례, 발달성 언어장애 4례, 기타 4례로 나타났으며 이상소견을 보인 환아 중 7례는 전음성 난청이었으며 8례는 감각신경성 난청이었다. 또한 ABR 검사상 정상을 보인 18개월에서 7세 사이의 I파 및 V파의 평균잠복기 및 표준편차는 각각 $1.40{\pm}0.13$, $5.57{\pm}0.26$이었으며, I-V의 정점간 잠복기는 $4.18{\pm}0.24$였다. 중등도 이상의 감각신경성 난청환아의 4례에서 보청기를 착용하였으며 이들을 추적 관찰하였다. 결 론: 언어발달장애를 주소로 내원하는 소아들에게 선별검사로서의 ABR은 반드시 필요한 것으로 생각되며 이것을 통해 감각신경성 난청을 조기 발견하고 감각 신경성 난청의 경우 보청기를 사용하여 조기 치료함으로써 이들의 신경학적 발달 및 사회적 적응에 도움을 줄 수 있을 것이다.

• 대한감각통합치료학회지
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• 제18권3호
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• pp.1-13
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• 2020

목적 : 본 연구는 주의력결핍 과잉행동장애(Attention Deficit Hyperactivity Disorder; ADHD) 아동과 일반 아동을 대상으로 감각처리능력과 시지각 기술을 비교하고자 하였다. 연구방법 : 연구대상은 지역적 환경이 동일한 아동으로 선정하였다. 소아정신과에서 ADHD로 진단받은 아동 25명과 초등학교 1, 2학년의 일반 아동 51명을 대상으로 감각처리능력과 시지각 기술을 평가하였다. 아동의 감각처리능력을 측정하기 위해 감각프로파일(Sensory Profile; SP)을 사용하였고 시지각 기술을 측정하기 위해 한국판 시지각 발달검사(Korean Developmental Test of Visual Perception-2; K-DTVP-2)를 사용하였다. 두 군 간의 감각처리능력과 시지각 기술의 차이는 독립표본 t 검정을 사용하여 분석하였다. 결과 : ADHD 아동과 일반 아동의 감각프로파일(SP)의 모든 하위 영역에서 통계적으로 유의한 차이를 보였다. 감각요인을 비교한 결과 감각예민을 제외한 8가지 요인에서 통계적으로 유의한 차이를 보였다. K-DTVP-2의 모든 시지각 지수에서 유의한 차이를 보였다. K-DTVP-2의 하위 항목 표준점수를 비교한 결과 공간위치(p=.031), 도형-배경(p=.001), 시각 통합(p=.005), 눈-손 협응(p=.000), 따라 그리기(p=.044), 공간관계(p=.006)에서 통계적으로 유의한 차이를 보였다. 결론 : 본 연구는 임상에서 ADHD 아동의 행동의 특성을 이해하는데 감각처리능력과 시지각 기술이 중요하다는 근거가 되며 ADHD 아동의 평가, 교육 및 연구에 도움을 제공할 수 있다는 점에서 의미가 있다.

• Animal Bioscience
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• 제35권9호
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• pp.1340-1350
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• 2022

Objective: Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH. Methods: We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genome-wide selection signatures have been scanned with four methods: heterozygosity (H_P), fixation index (F_ST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (𝜃_π) ratio. Results: The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected. Conclusion: The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• 대한치과교정학회지
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• 제21권2호
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• pp.341-351
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• 1991

Dental maturity is one of the index of physiological maturity indicators. To investigate the relationship between dental maturity and chronological age, the author took the orthopantomograms of 984 students, aged 7 through 17 years, having normal occlusion. The orthopantomograms were examined and calcification degree of each tooth on the left side was rated according to the method described by Demirjian. On the basis of findings of this study, the following results were obtained. 1. The root completion periods of mandibular permanent teeth were as follows; Central Incisor M $8.32{\pm}1.03\;years$ F $7.96{\pm}1.04\;years$ Lateral Incisor M $9.40{\pm}1.30\;years$ F $9.01{\pm}0.90\;years$ Canine M $12.81{\pm}1.24\;years$ F $11.42{\pm}0.94\;years$ 1st Premolar M $12.76{\pm}1.74\;years$ F $12.19{\pm}1.33\;years$ 2nd Premolar M $13.31{\pm}1.88\;years$ F $12.88{\pm}1.49\;years$ 1st Molar M $9.60{\pm}1.69\;years$ F $9.30{\pm}1.16\;years$ 2nd Molar M $14.38{\pm}1.73\;years$ F $13.96{\pm}1.63\;years$ 2. Sexual differences in same age group at given calcification stage were not significant statistically. 3. The developmental order in mandibular permanent teeth was as follows; a) central incisor, b) lateral incisor, c) 1st molar, d) canine and 1st premolar, e) 2nd premolar, f) 2nd molar.

• 대한감각통합치료학회지
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• 제3권1호
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• pp.37-47
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• 2005

Objective : This study was to find out whether there was a difference between parenting stress of parents with and without sensory defensiveness and level of the quality of life, to analyze the factors related with parenting stress of parents and quality of life and to develop intervention program to improve quality of life of parents that care children with problem on sensory process. Methods : The population of this study was consisted of 82 children aged from 3 to 7 years and was treated occupational therapy in clinics or welfare centers for disabled persons. Parenting stress was assessed with Parenting Stress Index and the quality of life scales used by Lee Jeong-Eun was used to assess the level of quality of life. Result : The difference between parenting stress with and without sensory defensiveness and level of quality of life was only shown in parenting stress, and the correlation between parenting stress with and without sensory defensiveness and quality of life indicated negative correlation in both sensory defensiveness and no sensory defensiveness group(r=-0.52, r=-0.65, p<0.05). This study found there was significant difference between quality of life factors affecting parenting stress of parents and parenting stress factors affecting quality of life in sensory defensiveness and no sensory defensiveness group. Conclusion : The study showed that clinicians must develop appropriative intervention program with sensory defensiveness or without sensory defensiveness for decreasing parenting stress and increasing quality of life for their parents.