• Title/Summary/Keyword: developmental pattern

Search Result 451, Processing Time 0.026 seconds

The Effects of Children's Metastrategic Activities on Strategies to Control Variables at a Scientific Reasoning Task

  • Jang, Myoung-Duk;Yang, Il-Ho;Jeong, Jin-Woo
    • Journal of the Korean earth science society
    • /
    • v.23 no.2
    • /
    • pp.154-165
    • /
    • 2002
  • The purpose of this study was to examine the effects of metastrategic exercise on a scientific reasoning strategy to control variables, and investigate the developmental patterns in the strategy usage within a given period. Two groups composed of 90 fifth grade students engaged in a scientific reasoning task over six daily sessions. Additionally, one group engaged in metastrategic exercise on fictional students' strategies of controlling variables on the task, while the other spent equivalent time on an unrelated task. Based upon results of the study, the following conclusions can be drawn. First, the metacognitive exercise on the strategy to control variables has positive and long-standing effects on the strategy performance at the reasoning task. The exercise also takes effect of near-transfer. Taking into consideration only about sixty minutes of metastrategic practice, the results provide the validity of the activity in order to develop children's reasoning strategies. Second, in a scientific reasoning task, each child seems to go through one out of two developmental patterns in their usage of reasoning strategies: gradual change or fundamental change. Considering the ratio of pattern of fundamental change between the two groups, it is clear that the metacognitive exercise influences the developmental pattern of strategy usage.

Intracellular Localization and Developmental Changes of Purine Catabolic Enzymes during Germination in Cotyledons of Rape Seedlings (발아중 유채자엽 퓨린 분해효소의 활성변화 및 세포내 위치)

  • 권덕기
    • Journal of Plant Biology
    • /
    • v.28 no.3
    • /
    • pp.225-232
    • /
    • 1985
  • Intracellular localization and the developmental changes in activities of uricase and allantoinase during germination were investigated with the cotyledons of rape(Brassica napus L.) seedlings. The development anddisappearance of uricase activity took place independently of light, but allantoinase activity was increased by light. The temporal pattern of uricase activity showed that uricolysis was actively taking place in the cotyledons during their early stages of germination. While uricase can be localized in the microbody fraction isolated from crude organelle extracts of the cotyledons by density gradient centrifugation, most of the allantoinase activity found in the microbody fraction did not appear to be an integral part of the microbody.

  • PDF

Taxonomy of the Genus Symphyocladia (Rhodophyta) (한국산 홍조식물 보라색 우무속(Symphyocladia)직물의 분류)

  • Lee, In-Kyu
    • Journal of Plant Biology
    • /
    • v.38 no.3
    • /
    • pp.297-303
    • /
    • 1995
  • Four species of Symphyocladia growing along the coast of Korea were investigated in taxonomic point of view. Characters available for identification of the species were; difference in gross morphology, degree of cortication in vegetative axis, presence or absence of vegetative trichoblasts, and developmental pattern of stichidia. Vegetative structure and reproductive organs in developmental anatomy were similar among species. Branching pattern and occurrence of vegetative trichoblasts adopted for systematic criteria between Pterosiphonieae and Polysiphonieae, and between Symphyocladia and Pterosiphonia were no more confidential. The degree of congenital fusion of laterals with the parent axes was considered as only main character to distinguish Symphyocladia from Pterosiphonia.

  • PDF

Structure and Dynamics of Korean Red Pine Stands Established as Riparian Vegetation at the Tsang Stream in Mt. Seorak National Park, Eastern Korea

  • Chun, Young-Moon;Park, Sung-Ae;Lee, Chang-Seok
    • Journal of Ecology and Environment
    • /
    • v.30 no.4
    • /
    • pp.347-356
    • /
    • 2007
  • The structure and dynamics of Korean red pine stands established in the riparian zone were studied in the Tsang stream in Mt. Seorak National Park, in east-central Korea. Pine stands were classified into four successional stages, the initial, establishing, competitive, and stabilizing stages, based on the age distribution of a dominant tree, Pinus densiflora, the vegetation stratification, and the microtopography of the riverine environment. The stages usually corresponded to disturbance frequencies, depending on the horizontal and vertical distances from the watercourse. Stands of the initial and establishing stages lacked tree or subtree layers, or both. As stands progressed through the developmental stages, soil particle size became finer and moisture retention capacity was improved. The stand ordination reflected the developmental stage, and the species ordination differentiated species specializing in relatively dry and wet habitats. The results of the analysis of vegetation dynamics provided ecological information which will be useful for understanding the developmental processes of vegetation established in riparian zones. Species diversity indices usually increased across developmental stages, following the typical pattern for successional processes. We discuss the importance and necessity of riparian vegetation in Korea, where most riparian forests have disappeared due to excessive human land use.

The Process of Modernization of the Site Plan and Plan of Conventional Rural Houses - Based on the Houses in SamGa Village, YongIn County Kying-gi Province - (주택의 배치 및 평면의 변화를 중심으로 본 재래식 농촌주택의 근대화 과정에 관한 연구 - 경기도 용인군 용인읍 삼가 1,3리 마을 주택을 중심으로 -)

  • Kim, Sung Woo;Lee, You Mee
    • Journal of architectural history
    • /
    • v.4 no.1
    • /
    • pp.79-92
    • /
    • 1995
  • The study is about the process of modernization of conventional rural houses in Kyung-gi province. It alms to identify the pattern of change, particularly focusing on the changes of the site plan and plan. The site of study is Samga Village, in YongIn County, near Seoul. The study discusses the process of modernization during the three decades from 1960 to 1980. The basic information was obtained through field research and site analysis, and the study relies predominatly on observational and statistical analysis. Four developmental stages can be clearly identified which are ; (1) Traditional type, (2)Modified-traditional type, (3) Saemaul type, and (4) The type of urban houses. The analysis was done through identification of changing site plan and plan. It is interesting to note that the changes of these elements show a certain pattern of sequential steps which also can be classified according to the four developmental stages mentioned above. The pattern of site design was consistantly maintained while plan and building system became very different However, the process of modernization of Korean rural houses was the process of producing a certain type of architecture that is not universal but uniquely Korean.

  • PDF

Prediction of Developmental Ability of In Vitro Fertilized Porcine Embryos by Analysis of Early Cleavage Pattern (체외수정 돼지 배아의 초기 분할 양상 분석에 의한 발달능 예측)

  • Jeon, Yu-Byeol;Biswas, Dibyendu;Yoon, Ki-Young;Hyun, Sang-Hwan
    • Journal of Embryo Transfer
    • /
    • v.24 no.1
    • /
    • pp.65-69
    • /
    • 2009
  • The aim of the present study was to investigate the cleavage pattern, its developmental ability and apoptosis of porcine embryo in vitro. Morphology data on a total of 919 embryos were analyzed retrospectively. Forty-eight hours after insemination, embryos were classified into five groups based on the cleavage state as follows; 1 cell, 2 cell, 4 cell, 5 to 8 cell and fragmentation. These groups were cultured another 120 hours and then evaluated for blastocyst formation. Blastocyst formation rates were significantly higher in 4 cell (42.5%) and 5 to 8 cell (48.6%) cleaving groups than in other groups (p<0.05). On the other hand, 2 cell and fragmentation groups produced 4.9% and 3,9% blastocysts, respectively. And we could verify that in the event of 2 cell block and fragmentation of embryo. To analyze the apoptotic frequency in preimplantation development of porcine IVF embryos, all cells of each blastocyst were performed by TUNEL assay. There were no significantly differences in the total cell numbers of embryos and apoptotic cell rate in blastocysts among the each classified groups. Data suggest that 4 cell and 5 to 8 cell cleaving embryos at 48 hour after insemination have high developmental competence, and may be an useful parameter to predict the development of preimplantation embryos and to study using preimplanation embryonic research.

Expression Patterns of SQS in Different Tissues in Amaranth Grains (Amaranthus cruentus L.)

  • Young-Jun Park
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2022.10a
    • /
    • pp.294-294
    • /
    • 2022
  • To date, there have been no reports on the cloning and characterization of a gene encoding SQS from Amaranthus, although there have been some reports on methods of extracting and purifying squalene from Amaranthus seeds. In this study, we monitored the expression pattern of the amaranth SQS gene in seeds at different developmental stages and in different tissues. The transcript expression pattern of the SQS gene was investigated using total RNA isolated from seeds at different stages of development. There were low levels of SQS transcripts at the early stage of seed development, and the levels remained low until the middle developmental stage. The expression of SQS increased rapidly to reach a peak at the mid-late developmental stage, and then declined dramatically. This pattern of expression was consistent with the results of RT-PCR analyses. All RNA samples generated a fragment of the expected size (183-bp). The amaranth SQS was expressed at low levels during the initial to middle stages of seed development, and its expression level increased at the mid-late development stage. Also The tissue-specific expression of amaranth SQS was determined by quantifying its mRNA in total RNA isolated from the leaves, petioles, stems, and roots of seedlings at the four- and six-leaf stages. Using qRT-PCR and RT-PCR analysis, we detected amaranth SQS transcripts in some of the tissues at the six-leaf stage, but in none of the tissues from plants at the four-leaf stage. SQS transcripts accumulated in almost equal amounts in stems and roots, while a lower level accumulated in leaves and petioles during seedling development at the four- to six-leaf stages. This study provides useful information about the molecular characterization of the SQS clone isolated from grain amaranth. A basic understanding of these characteristics will contribute to further studies on the amaranth SQS.

  • PDF

Comparative Ultrastructure of Secretory Granules of the Submandibular Gland in the Korean Spider Shrew, Sorex caecutiens, the Lesser White-toothed Shrew, Crocidura suaveolens and the Big White-toothed Shrew, Crocidura lasiura

  • Jeong, Soon-Jeong;Bae, Chun Sik;Lee, Hye-Yon;Choi, Baik-Dong;Yoon, Myung-Hee;Jeong, Moon-Jin
    • Applied Microscopy
    • /
    • v.42 no.4
    • /
    • pp.186-193
    • /
    • 2012
  • The ultrastructure of the secretory granules of the submandibular gland was examined in the Korean spider shrew, Sorex caecutiens, lesser white-toothed shrew, Crocidura suaveolens and big white-toothed shrew, C. lasiura. The mucous and serous acinar granules of S. caecutiens with a border of the lucid corona differed from those of C. suaveolens and C. lasiurar with a dense lateral border. The mucous acinar granules of C. lasiura with several bands producing a variety of patterns in the matrix were similar to those of C. suaveolens. The serous acinar granules of C. lasiura had a homogenous pale center surrounded by minute dense specks or had an unusual substructure showing a geometric pattern according to the inclusions in the pale matrix of the granules. This is the first report of an unusual substructure showing a geometric pattern of the serous acinar granules of C. lasiura. The myelin-like body was observed in the granular duct cell of the three species of shrew. The myelin-like body of S. caecutiens with layers of unit membranes was different from that of C. suaveolens and C. lasiura with paired membranes. Therefore, the layers composing of the paired membranes of the myelin-like body might be one of the characteristics of Crocidura.