• Title/Summary/Keyword: Sequential relationship

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Relationship between Physicochemical Properties, Heavy Metal Contents and Magnetic Susceptibility of Soils (토양의 물리화학적 특성, 중금속 함량, 대자율 간의 상호관계 연구)

  • Chon, Chul-Min;Park, Jeong-Sik;Kim, Jae-Gon;Lee, Youn-Soo
    • Journal of the Mineralogical Society of Korea
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    • v.23 no.4
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    • pp.281-295
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    • 2010
  • This paper deals with magnetic susceptibility, mineralogy, soil properties (pH, EC, CEC, loss on ignition), iron and manganese oxides, the content and partitioning of heavy metals (As, Cd, Cr, Cu, Ni, Pb, Zn), and their mutual relationship in the soil samples of an unpolluted, abandoned mine area, and industrial complex area. The various minerals derived from weathered bedrock were identified by X-ray diffraction in the unpolluted soil samples, except for the magnetic minerals. XRD analysis also revealed the existence of hematite and magnetite related to mine tailings and waste rocks in the abandoned mine area samples. The industrial complex area samples had carbonate minerals, such as calcite and dolomite, that might be due to anthropogenic deposition. The sum of the reducible, oxidizable, and residual fractions was over 80% for the abandoned mine area samples and over 50% for the industrial complex area samples using the sequential extraction method. The industrial complex area samples had a relatively high carbonate fraction that was associated with carbonate minerals. The content of aqua regia-extractable Fe, Mn, As, and Zn had a high positive correlation with the content of the dithionite-citrate-bicarbonate (DCB)-extractable method related to Fe/Mn oxide phases. The 54% and 58% of aqua regia-extractable Fe and As content, respectively, acted together with the concentrations of the DCB-extractable phases. Magnetic susceptibility values of total samples ranged from 0.005 to $2.131{\times}10^{-6}m^3kg^{-1}$. The samples including iron oxide minerals, such as hematite and magnetite, had a high magnetic susceptibility. The magnetic susceptibility showed a significant correlation with the heavy metals, Cd (r=0.544, p<0.05), Cr (r=0.714, p<0.01), Ni (r=0.645, p<0.05), Pb (r=0.703, p<0.01), and Zn (r=0.496, p<0.01), as well as Fe (r=0.608, p<0.01) and Mn (r=0.615, p<0.01). The aqua regia-extractable Fe and Mn content had a significant positive correlation with Cd, Cr, Cu, Ni, and Zn. However, the DCB-extractable Fe and Mn content had a significant positive correlation with As and Ni, indicating that the heavy metals were associated with Fe and Mn oxide minerals.

Potassium Supply Characteristics in Different Forest Soils (지역별(地域別) 산림토양(山林土壤)의 K(Potassium) 공급(供給) 특성(特性))

  • Jin, Hyun-O;Kim, Jun-Hwan
    • Journal of Korean Society of Forest Science
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    • v.90 no.1
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    • pp.64-73
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    • 2001
  • Generally potassium in the soil can be remained as water soluble, exchangeable, and available types, respectively. Theses types of potassiums are also known to keep their kinetic relationships to each other. The Purpose on this research was to investigate types and relationships of potassium in the soil, and the characteristics of potassium supply in different forest soils. The results could be summarized as follows; 1. The amounts of available potassium in A and B horizon soils by continuous leaching with 0.01N-HCl were as follows : for A Horizon soils, pohang(Gray brown forest soils), Changsung (Brown forest soils), and Youngwol(Dark red forest soils) were ranged from 0.2me/l00g to 0.8me/100g, Taean(Red and Yellow forest soils) was 0.1-0.6me/100g, Kapyung(Brown forest soils) was 0.2-0.4me/100g. For the B layer, Youngwol was 0.1-0.5me/100g, Pohang, Taean, Kapyung were 0.1-0.4me/100g, Changsung was 0.1-0.3me/100g, respectivly. 2. Of ten times-pulse leaching with 0.01N-HCl for A layer soil, more 80% of total available potassium leaching were recovered by the second pulse as leachate for Pohang, Changsung, Youngwol, while similar amounts of potassium in the leachate were obtained with the third pulse leaching for Kapyung, Taean, respectively, On the other hand, the 80 % release of available potassium from the B layer soil was obtained by the second pulse leaching for all areas investigated. 3. For the relationships between soluble potassium and exchangeable potassium, the exchangeable potassium was increased while the soluble potassium was not changed significantly in B layer. And both soluble potassium and exchangeable potassium in A layer were similar. For the relationship between exchangeable potassium and available potassium in both A and B layers, the amounts of available potassium increased by 1.2 to 1.5 times as the exchangeable potassium increased. 4. For distribution of all types of potassium throughout locations investigated, the types of potassium were in the decreasing orders of available, exchangeable, and soluble. 5. The simplified method for an analysis of all types of potassium by sequential leaching with 0.01N-HCl should be developed not only with respect to time-saving and efficiency but also verification of the relationship between available potassium and tree growth.

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Knowledge graph-based knowledge map for efficient expression and inference of associated knowledge (연관지식의 효율적인 표현 및 추론이 가능한 지식그래프 기반 지식지도)

  • Yoo, Keedong
    • Journal of Intelligence and Information Systems
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    • v.27 no.4
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    • pp.49-71
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    • 2021
  • Users who intend to utilize knowledge to actively solve given problems proceed their jobs with cross- and sequential exploration of associated knowledge related each other in terms of certain criteria, such as content relevance. A knowledge map is the diagram or taxonomy overviewing status of currently managed knowledge in a knowledge-base, and supports users' knowledge exploration based on certain relationships between knowledge. A knowledge map, therefore, must be expressed in a networked form by linking related knowledge based on certain types of relationships, and should be implemented by deploying proper technologies or tools specialized in defining and inferring them. To meet this end, this study suggests a methodology for developing the knowledge graph-based knowledge map using the Graph DB known to exhibit proper functionality in expressing and inferring relationships between entities and their relationships stored in a knowledge-base. Procedures of the proposed methodology are modeling graph data, creating nodes, properties, relationships, and composing knowledge networks by combining identified links between knowledge. Among various Graph DBs, the Neo4j is used in this study for its high credibility and applicability through wide and various application cases. To examine the validity of the proposed methodology, a knowledge graph-based knowledge map is implemented deploying the Graph DB, and a performance comparison test is performed, by applying previous research's data to check whether this study's knowledge map can yield the same level of performance as the previous one did. Previous research's case is concerned with building a process-based knowledge map using the ontology technology, which identifies links between related knowledge based on the sequences of tasks producing or being activated by knowledge. In other words, since a task not only is activated by knowledge as an input but also produces knowledge as an output, input and output knowledge are linked as a flow by the task. Also since a business process is composed of affiliated tasks to fulfill the purpose of the process, the knowledge networks within a business process can be concluded by the sequences of the tasks composing the process. Therefore, using the Neo4j, considered process, task, and knowledge as well as the relationships among them are defined as nodes and relationships so that knowledge links can be identified based on the sequences of tasks. The resultant knowledge network by aggregating identified knowledge links is the knowledge map equipping functionality as a knowledge graph, and therefore its performance needs to be tested whether it meets the level of previous research's validation results. The performance test examines two aspects, the correctness of knowledge links and the possibility of inferring new types of knowledge: the former is examined using 7 questions, and the latter is checked by extracting two new-typed knowledge. As a result, the knowledge map constructed through the proposed methodology has showed the same level of performance as the previous one, and processed knowledge definition as well as knowledge relationship inference in a more efficient manner. Furthermore, comparing to the previous research's ontology-based approach, this study's Graph DB-based approach has also showed more beneficial functionality in intensively managing only the knowledge of interest, dynamically defining knowledge and relationships by reflecting various meanings from situations to purposes, agilely inferring knowledge and relationships through Cypher-based query, and easily creating a new relationship by aggregating existing ones, etc. This study's artifacts can be applied to implement the user-friendly function of knowledge exploration reflecting user's cognitive process toward associated knowledge, and can further underpin the development of an intelligent knowledge-base expanding autonomously through the discovery of new knowledge and their relationships by inference. This study, moreover than these, has an instant effect on implementing the networked knowledge map essential to satisfying contemporary users eagerly excavating the way to find proper knowledge to use.

Fractionation of Heavy Metals and Correlation with Their Contents in Rice Plant Grown in Paddy near Smelter Area (제련소 인근 논 토양 중 중금속 형태 분류 및 수도체중 중금속 함량과의 상관성)

  • Kim, Seong-Jo;Baek, Seung-Hwa;Moon, Kwang-Hyun
    • Korean Journal of Environmental Agriculture
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    • v.15 no.1
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    • pp.1-10
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    • 1996
  • The contents of heavy metals in soil near the Janghang smelter area were observed to understand present status and relationship between their fraction and the absorption by rice. The soil samples were taken from the eight sites of the paddy fields in 1982 and 1990, and analysis on heavy metals including Cd, Zn, Cu and Pb was performed. The results were as follows: Total contents of heavy metals in the samples of 1990 were higher than those of 1982. The order of increasing ratio was Cu > Zn > Pb > Cd and the variation of Cd content by sequential differente extracting was residual > exchangeable > dilute acid-extractable fractions and its increasing range was from 38 to 71% during nine years. The ratio of immobile heavy metals bound within an oxide or silicate matrix of Fe-Mn oxide bound and residual in surface soil was that Cd, Pb, Cu and Zn were 31.65, 42.22, 76.57 and 79.49%, respectively, and their mobile ratios of exchangeable, dilute acid-extractable and organically bound were more than 20.28%. Those of mobile Cd, Pb, Cu and Zn were 68.35, 55.78, 23.43 and 20.28%, respectively. Correlation between the heavy metal contents in surface soil and those in tissue of rice plant, such as leaf blade, leaf sheath, stem and panicle axis, were significant, but were not significant in subsurface soil. The dilute acid-extractable and organically bound fractions of Cd, Cu, Pb and Zn in surface soil were more significantly correlated with those in tissues of paddy rice.

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Effect of Visual Perception by Vision Therapy for Improvement of Visual Function (시각기능 개선을 위한 시기능훈련이 시지각에 미치는 영향)

  • Lee, Seung Wook;Lee, Hyun Mee
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.4
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    • pp.491-499
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    • 2015
  • Purpose: This study was to examine how decline of visual function affects visual perception by assessing visual perception after improving visual function through visual training, and observing the change in the cognitive ability of visual perception. Methods: This study analyzes the visual perceptual evaluation (TVPS_R) of 23 children below age 13($8.75{\pm}1.66$) who have visual abnormalities, and improves visual function after conducting vision training (vision therapy) of the children. Results: Convergence increased from average $3.39{\pm}2.52{\Delta}$ (prism) to $13.87{\pm}6.04{\Delta}$ in the measurement of long-distance disparate points, and from average $5.48{\pm}3.42{\Delta}$ to $18.43{\pm}7.58{\Delta}$ in the measurement of short-distance disparate points. Short-distance diplopia points increased from $25.87{\pm}7.33cm$ to $7.48{\pm}2.87cm$, and as for accommodative insufficiency, short-distance blur points increased from $19.57{\pm}7.16cm$ to $7.09{\pm}1.88cm$. In the visual perceptual evaluation performed before and after improving visual function, 6 items except visual memory showed statistically significant improvement. By order of significant improvement, response gap was highest with $17.74{\pm}16.94$(p=0.000) in visual closure, followed by $15.65{\pm}17.11$(p=0.000) in visual sequential-memory, $13.65{\pm}16.63$(p=0.001) in visual figure-ground, $12.74{\pm}18.41$(p=0.003) in visual form-constancy, $6.48{\pm}10.07$ (p=0.005) in visual discrimination, and $4.17{\pm}9.33$(p=0.043) in visual spatial-relationship. In the visual perception quotient that added up these scores, the response gap was $15.22{\pm}8.66$(p=0.000), showing a more significant result. Conclusions: Vision training enables efficient visual processing and improves visual perceptual ability. It was confirmed that improvement of visual function through visual training not only improves abnormal visual function but also affects visual perception of children such as learning, perception and recognition.

An Ethnographic Study about Taegyo Practice in Korea (태교 실천에 대한 일상생활 기술적 연구)

  • 김현옥
    • Journal of Korean Academy of Nursing
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    • v.27 no.2
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    • pp.411-422
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    • 1997
  • The purpose of this study is twofold : (i) to investigate how much effort the married couples are making for the good health of both the pregnant woman and her unborn child from the time of their marriage to and during the period of conception : and (ii) to comprehensive investigate socio-cultural back-grounds which affect prenatal effort. Result of this study provide a basis for the prenatal care program which will be appropriate to our culture. This study has been done by the ethnographic research method. The subjects of this study are 53 people in all consisting of 33 pregnant women and 20 husbands. In order to investigate socio-cultural factors which influence Taegyo, producers of Taegyo music were interviewed. In addition the researcher surveyed the markets of Taegyo music, participated in special courses of prenatal education, analyzed the content of the books and periodicals dealing with Taegyo, and collected the concept of Taegyo distributed by the mass media. The full-fledged study continued for eight months from February to August.1996. The data were analyzed as soon as they were collected. Spradly's(1979, 1980) developmental, sequential method of domain analysis. taxonomic analysis, componential analysis, and theme analysis in this order was adopted as the procedure of analyzing the data. To obtain the exactness of study, Sandelowski's (1986) four criteria, that is, Credibility, Fittingness, Auditability, and Confirmability were applied to all stages of data collection, data analysis, the interpretation of the result, and the description of the result. The following are the result : 1. The couples' Taegyo at the stage of preconception was related to their physical, psychological, spiritual conditions under which a healthy baby will be born. Specific methods they prefer are : "the choice of one's spouse." "physical check-up," "physical good health, " "praying, " and so on. 2. When the marriod couple have sex in order to conceive, their Taegyo was related to the imposition of their physical, psychological, and environmental conditions. Specific methods they prefer are : "having sex at specific time, " "having sex in nice place." "to purify their minds while having sex," and so on. 3. The married couples' Taegyo while they are in pregnancy was related to the imposition of their physical. psychological, emotionmental. environmental, social and spiritual conditions. Specific methods they prefer are : "listening to music. " "reading," "looking at beautiful things only," "to avoid looking at or listening to bad things." "to eat food in good shape, " "to avoid drugs," "eating Korean herbal medicine." "sexual abstinence," "to avoid dangerous places," "to keep emotional tranquility," "moderate exercises and rest." "leading a pure life." "praying." "being aware of their words and behavior." "for the couple to keep a good relationship." "interaction with their unborn child," "to support Taegyo for pregnant women," and so on. 4. The married couple put Taegyo into practice on the basis of the following principles : the principle of respecting an unborn child, the principle of forming a good disposition. the principle of top-down parental love, the principle of synergy between a pregnant woman and her unborn child, the principle of expecting a good child, the principle of forming a good habit, and the principle of acquiring a parental role. 5. The practice of Taegyo is influenced by such factors as the married couple, the supporting system, and the mass media. As the husband -and-wife factor, their information of Taegyo, the degree of importance is assigned to their characters, their time to spare, their healthiness, the age of pregnant woman, their conception plan, their religion, their belief of the Taegyo effects, and the birth of a baby in this order. The factor of the supporting system consists of her husband's support, her family support, and her neighbor's support. The mass media factors include the broadcasting media, books specialized in Taegyo, periodicals for pregnant women, booklets for advertizing powdered milk, Taegyo music of record manufacturing companies, and the teaching materials for gifted children. Among these the mass media is especially taking advantage of Taegyo as its main source of economic profits are leading the public behavior pattern to a prodigal one. Taegyo is a self-control behavior which requires practice for the following : the physical and psychological good health of the pregnant woman and her unborn child, the development of the unborn child's good character, the development of the unborn child's intelligence and talents, the expectation of the unborn child's good features. shape a good habit, the expectation of the unborn child's bright future, and the learning of a parental role, the expectation of male birth. Above all it is a type of our good cultural tradition which pursues a value higher than the one that the prenatal care does. The principles of pregnancy care inherent in the habit of Taegyo will provide us a guideline for the development of the prenatal care.

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Pollution of Pb in paddy field soil and rice plants at roadside areas;I. Pollution of Pb in paddy field soil and its chemical forms (도로변(道路邊)에 인접(隣接)한 경작지(耕作地) 토양(土壤) 및 작물체중(作物體重)의 연오염(鉛汚染) 제(第)1보(報) 경작지(耕作地) 토양중(土壤中)의 연오염(鉛汚染) 및 화학적(化學的) 형태(形態))

  • Lee, Seog-June;Kim, Jang-Eok
    • Korean Journal of Environmental Agriculture
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    • v.10 no.1
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    • pp.1-10
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    • 1991
  • The object of this stduy was to investigate the pollution of Pb in paddy field soil with different distance from roadside and to find out the relationship between the ratio of chemical fractions of total Pb and soil characteristics. Lead from automobiles is exhausted as particulates composed primarily of halide compounds (PbBrCl, $PbBr_2$, $PbCl_2$). The samples of soil were collected directly from the paddy fields with different distance from the roadside of highway and expressway which are located in Kyungpook province. A sequential extraction procedure was used to fractionate Pb in paddy field soil into the disignated forms of water soluable, exchangeable, organically bounded, carbonate, sulfide, and residual Pb. Results obtained are summerized as follows. 1. The content of Pb in paddy field soil was the highest in Chungdo, 30.0 ppm, the lowest in Koryung, 14.8 ppm, and the total average content was 21.9 ppm. The effect of traffic volume was not clear, but a slight difference according to the order of opened year of roads was showed. 2. The effect of distance from roadside was not clear. The content of Pb in paddy field soil with different distance from roadside was 22.2 ppm within l0m, 22.1 ppm in 10∼30m, 22.2 ppm in 30∼50m. and 21.3 ppm beyond 50m. 3. The distribution of Pb fractions in soil showed a wide difference depending on soil properties. The average content of exchangeable. organically bounded, carbonate, sulfide, and residual Pb was 8.6%, 33.6%, 29.8%, 21.5%, and 6.7%, of total Pb in the soil, respectively. 4. The content of organically bounded Pb in soil showed highly positive correlation with organic matter and CEC, while the content of exchangeable Pb was highly negative correlation. 5. With higher soil organic matter and CEC, organically bounded Pb fraction tend to be higher but exchangeable Pb fraction tend to be lower. Other forms of Pb showed no difference with soil organic matter contend and CEC. The distribution of Pb fraction related to CEC showed similiar tendency with that of organic matter content.

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Behaviors of Arsenic in Paddy Soils and Effects of Absorbed Arsenic on Physiological and Ecological Characteristic of Rice Plant I. Distribution of Arsenic Fractions in Paddy Soils and their Relations to Arsenic Content in Brown Rice (토양중(土壤中) 비소(砒素)의 행동(行動)과 수도(水稻)의 비소흡수(砒素吸收)에 의(依)한 피해(被害) 생리(生理), 생태(生態)에 관(關)한 연구(硏究) I. 토양중(土壤中) 비소(砒素)의 형태(形態)와 현미중(玄米中) 비소함량(砒素含量)과의 관계(關係))

  • Lee, Min-Hyo;Lim, Soo-Kil;Kim, Bok-Young
    • Korean Journal of Environmental Agriculture
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    • v.5 no.1
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    • pp.35-42
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    • 1986
  • This study was carried out to investigate the distribution of arsenic (As) fractions in paddy soils in relation to some soil characteristics and to find out the relationship between As fractions in soil and As content in brown rice. Soils and rice samples were collected from paddy field adjacent to arsenic mining and refinery sites. Sequential extraction procedures were used to fractionate As in soils into the designated forms of water soluble-As, Al-As, Fe-As, Ca-As, and residual-As. The results obtained were as follows: 1. The percent distribution of As fractions in soil showed a wide difference depending on some soil properties. The relative abundance of the extractable inorganic As fractions was in the order of Fe-As>Al-As>Ca-As>Water soluble-As regardless of mining and refinery sites. Residual-As fraction was more abundant in mining site than in refinery site. 2. With increasing soil pH, the percent distribution of Fe-As and Al-As fractions were decreased, but that of Ca-As and Residual-As fractions increased. The percent distribution of Al-As fraction in soil was negatively correlated with soil CEC, but others showed positive relationships. 3. Active Al and Fe content, and exchangeable Ca content in soil were positively correlated with the percent distribution of Al-As, Fe-As, and Ca-As fractions in soil respectively, and higher correlation between them was shown in mining site than in refinery site. 4. Soil As fractions, except for water soluble-As, showed significant correlation with among each others and also with 1N HCl extration method using as the common soil As extractant in Korea. 5. Arsenic content in brown rice had highly significant correlation with Al-As fraction in soil and it also showed significant correlation with Fe-As and Ca-As fractions, Total-As, and 1N-HCl extractable As.

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Failure Properties of Common Tendon Origins at the Human Elbow after Static and Repetitive Loading (정적 및 반복하중 시의 주관절 Tendon의 파괴 물성치 측정)

  • Han, Jeong-Su;Lee, Gwan-Hui;Yu, Jae-Yeong
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.393-401
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    • 1998
  • Based on clinical observations, it is suspected that the bone-tendon origin is the site where piratical failure, leading to pathophysiological changes in the humeral epicondyle after repetitive loading, is initiated Mechanical properties and failure patterns of the common extensor and flexor tendons of the humeral epicondyle under static and repetitive loading have not been well documented. Our goal was to determine mechanical properties of failure strength and strain changes, to correlate strain changes and the number of cyclic repetitions, and to identify the failure pattern of bone-tendon specimens of common extensor and flexor tendons of the humeral epicondyle. Mechnaical properties of human cadaver bone-tendon specimens of the common extensor and flexor tendons of the humeral epicondyle were tested under two different loading rates. No statistically significant difference in ultimate tensile strength was found between male and female specimens or between slow (10 mm/sec) and fast elongation (100 mm/sec) rates. However, a statistically significant difference in ultimate tensile strength between the common extensor (1190.0 N/$cm^2{\pm}$388.8) and flexor 1922.0 N/$cm^2{\pm}$764.4)tendons was found (p<0.05). When loads of 25%, 33%, and 41% of the ultimate tensile strength of their contralateral sides were applied, the number of cycles required to reach 24% strain change for the common extersor and flexor tendons were approximately 8,893, 1,907, and 410, respectively. The relationship between cycles and loads was correlated ($R^2$=0.46) Histological observation showed that complete or partial failure after tensile or cyclic loadings occurred at the transitional zone, which is the uncalcified fibrocartilage zone between tendon and bone of the humeral epicondyle. Sequential histological sections revealed that failure initiated at the upper, medial aspect of the extensor carpi radialis brevis tendon origin. Biomechanical and hstological data obtained in this study indicated that the uncalcified fibrocartilage zone at the bone-tendon origin of the common extensor and flexor tendons is the weak anatomical structure of the humeral epicondyle.

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Mapping and Race Specific Reaction of the Resistance Gene Pi45(t) in Rice (벼 도열병 저항성 유전자 Pi45(t)의 균계 특이적 반응과 고밀도지도 작성)

  • Kim, Dong-Min;Ju, Hong-Guang;Yang, Paul;Han, Seong-Sook;Roh, Jae-Hwan;Ahn, Sang-Nag
    • Korean Journal of Breeding Science
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    • v.43 no.1
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    • pp.42-49
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    • 2011
  • QTL analysis for blast resistance was carried out using 140 $BC_3F_3$ lines derived from a cross between Ilpum as a recurrent parent and Moroberekan as a donor parent. 140 $BC_3F_3$ lines with the parents were inoculated with nine blast isolates. To identify QTLs for resistance to nine blast isolates, 134 SSR markers showing polymorphisms between the parents were genotyped for the 140 $BC_3F_3$ lines. A total of 17 resistance QTLs to nine isolates were detected on chromosomes 2, 3, 4, 6, 7, 9 and 10. The phenotypic variance explained by each QTL ranged from 8.2% to 26.4%. The Moroberekan alleles contributed the positive effect at these 17 QTL loci. In a previous study, the QTL, Pi45(t) for durable resistance to blast was identified using a sequential planting method. To know the relationship between Pi45(t) and the isolate-specific resistance gene, an $F_2$ population was developed from a cross between Ilpum and an introgression line harboring Pi45(t). $F_3$ lines segregating for the Pi45(t) were inoculated to three isolates. $F_3$ lines from the $F_2$ plants with the Moroberekan segment at the target region showed resistance to two isolates. This result seems to indicate that the Pi45(t) and the isolate-specific resistance gene are tightly linked or the resistance is controlled by the same gene(s). The markers linked to genes controlling blast resistance would be useful in developing blast resistance lines in the breeding program.