• Journal of Marine Life Science
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• v.9 no.1
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• pp.41-46
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• 2024

This study aimed to reconfirm the sex change scale and pattern of Tegillarca granosa. Although the sex ratio (female : male, female proportion) of T. granosa was 1:2.32 (30.2%) at the initial stage (2011) of the study, it was 1:0.94 (51.5%) after one year (2012) in the same population. The increase of the female proportion was greater in the 2+ year class (23.0%) when compared to the 1+ year class (19.2%). Overall, sex change ratio of 37.6% was observed in this population of T. granosa. The sex change ratio of the 2+ year class (39.3%) was higher than that of the 1+ year class (35.3%). And sex change ratio in the males (42.2%) was higher than that in the females (26.9%). The female proportion was the opposite of the result from 2006~2007, and one of the causes was presumed to be the difference in cumulative water temperature during the gonadal inactive stage (winter).

• The Korean Journal of Malacology
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• v.31 no.4
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• pp.315-322
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• 2015

The sex of bivalves is classified into gonochorism and hermaphroditism, and hermaphroditism is further divided into simultaneous (synchronous or functional), and sequential (asynchronous). The sequential hermaphroditism signifies sex reversal in accordance with seasons. In general, in the case of gonochoristic bivalves, manifestation of sex as female and male, after having identified the morphological sex, is limited to a period of the life cycle in any given individual. In order to accurately identify sex, continuous monitoring of changes in the sex during life cycle is necessary by tagging the sex. In the bivalves, sex reversal and sequential hermaphroditism has been reported in the Ostreidae, Pectinidae, Veneridae and Arcidae etc.. Most of these studies have reached this conclusion based on evidence derived from sex ratio change in accordance with the age within same populations. Sex change in the sequential hermaphroditic bivalves normally occurs when the gonad is undifferentiated between spawning seasons. Two factors are involved in sex determination and sex change in bivalves, namely genetic and environmental. However, more detailed research is needed on the effect of the genetic and environmental factors involved in sex determination and sex change of bivalves.

• The Korean Nurse
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• v.36 no.2
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• pp.49-63
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• 1997

This study was performed to provide preliminary data for the development of a useful instrument to measure the effect of sex education. The study was conducted with the voluntary participation of 155 college students enrolled in the course "Sexuality and Relationship" at Y university in Seoul. At the end of that course, they were asked to write freely about the change they had experienced on sexuality. All meaningful statements were elicited and classified into 7 categories; "Change of Knowledge", "Enlightenment", "Change of Attitude on Sexuality", "Buildup of Ability", "Buildup of. Identity", "Change of Emotion", "Change of Behavior:' There were significant changes in the areas of knowledge(28. 6%), enlightenment(27.4%), and attitudes(20.3%) about sexuality among these 7 categories. The Change of Knowledge category consists of 3 areas: "concretion of knowledge", "increase of information", and "correction of misunderstanding." In the category of Enlightenment, total 12 areas are included: "sex role", "erception of lack of knowledge", "importance of family", "life plan", "parent role", "value of life", "equality", "sexual autonomy", "importance of sexuality", "freedom of sexuality", "perception of sexual problem", and "meaning of love." The Attitude Change category consists of 8 areas. These are "being natural", "being progressive", "being sensitive", "being truthful", "being expressive", "being cautious", "being responsible", and "being confident". The category of Buildup of Ability includes 4 areas: "problem solving", "sex education", "relationship", and "communication". The category of Buildup of Identity includes "sexual identity", and "value of sexuality". The Emotional Change category includes 3 areas: "positive feeling", "negative feeling", and "breaking from negative feeling on sexuality". The Behavior Change category includes "sex-related behavioral change". In conclusion, up to now most researches on sex education effect measures only changes of knowledge, attitude, and behavior. But we believe the changes in "Enlightenment", "Buildup of Ability", "Buildup of Identity", "Change of Emotion", should be included in addition to knowledge, attitude, and behavior in the development of an instrument to measure the sex education effects. And the effect of sex education should measure the degree of learning of autonomy, enlightenment, and ability of behavior and so on rather than studying the simple changes in sexuality.enment", "Buildup of Ability", "Buildup of Identity", "Change of Emotion", should be included in addition to knowledge, attitude, and behavior in the development of an instrument to measure the sex education effects. And the effect of sex education should measure the degree of learning of autonomy, enlightenment, and ability of behavior and so on rather than studying the simple changes in sexuality.ng the simple changes in sexuality.

• Journal of the Korean Home Economics Association
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• v.29 no.3
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• pp.209-226
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• 1991

This study aimed at providing the basic data for the measurement of the attitude for socialization of household work by analysis of the attitude for socialization of houselhold work according to demographic variables, the degree of acceptance for living change. This study was composed of the attitude for the socialization of household work was based on time, quality, cost factor. The results of this study were as follows: 1. The attitude for socialization of household work was influenced by sex, age, marriage, sex $\times$ marriage and the degree of acceptance for living change. 2. The variables which affected the attitude for socialization of household work independently had influence on it in the following order : the degree of acceptance for living change, sex, house type. 3. The result of path analysis had confirmed that sex, age, income marriage, house type variable indirectly influenced the attitude for socialization of household work through the degree of acceptance for living change. Sex, and marriage variable directly influenced on the attitude for socialization of household work. Through the this study. The attitude for socialization of houselhold work was influnced by the degree of acceptance for living change. Change of household work is socialization of household work and right attitude to the socialization fof household work is necessary for satisfaction of variouse needs. for saving of time and money through the socialization of household work.

• Journal of the Korean Society of School Health
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• v.3 no.1
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• pp.119-134
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• 1990

The purpose of this study is to find out the need for sex education of middle school students and their parents. For the data collection, the survey was conducted during the period from September 10 to September 20, 1989 by using prepared questionnaire. A questionnaire was given to 592 students of 1st, 2nd and 3rd grade from four middle schools and to 408 their parents in Suwon City. The major results are summarized as follow; 1. Among the 25 questions were asked about knowledge of sex, the structure of reproductive organs, physical change during puberty, menstruation, Sexually stimulation and family plan were answered correctly by over 50% of the students. The higher the grade, the more the knowledge of sex. There was no significant difference between this knowledge and with eider sister or brother. Among the 20 questions were asked about knowledge of sex, sexually stimulation, pregnancy, emission, induced abortion and sexually transmitted disease were answered correctly by over 50% of the parents. 2. 30 questions were asked about attitude of sex, 47.7% of the students and 53.4% of the parents answered 'positive'. There was no significant difference between grade and sex of students. A significant difference '.vas not also found between years and education level of parents. 3. In case of students, experience of sex education was showed the structure of reproductive organs, physical change during puberty, temper during puberty, menstruation, emission more. In the event of parents, experience of sex education was showed the structure of reproductive organs, temper during puberty, menstruation, emission, relationship with apposite sex more. Most students felt that sex education should begin from the first grade of middle school and the first grade of high school strongly. In parents was showed the need for sex education from the primary school and the first grade of middle school highly. Namely, students and parents felt that sex education should begin from puberty. To help good developments and growth of middle school students with rapid change should be educated sex eduction properly for the occasion.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.12
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• pp.1503-1512
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• 1988

As the basic analysis to solve the within-and cross-speaker variability in phoneme based speech recognition, changes in pitch and formant frequencies of 8 Korean vowels with age and sex of speaker has been investigated by analyzing a large number fo samples. Conclusions obtained are as follows: 1) Changes in pitch frequency with age and sex of speaker for children are hard to distinguish and the difference of before and after the voice change is analyzed approximately 0.2 oct. for female an 0.9 oct. for male. 2) While most of the formants of vowel considerably change with the age of speaker, the change becomes smaller as the age becomes older. 3) While there is an indirect correlation between pitch and formant with change in age, it is hard to see a direct correlation. 4) When the objects of the recognition experiment by pitch and formants are various speakers in each age and sex, pitch also works as an efficient recognition parameter.

• Development and Reproduction
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• v.10 no.2
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• pp.79-84
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• 2006

We reviewed sex-change patterns in the wrasses Halichoeres poecilopterus, H. tenuispinis, Pteragogus flagellifer, and Pseudolabrus sieboldi inhabiting the coastal waters of Jeju, Korea, based on the sex distribution according to standard length and sex characteristics of the gonads. Halichoeres poecilopterus, H. tenuispinis, Pt. flagellifer, and Ps. sieboldi are protogynous hermaphroditic fish. Histological observations revealed that these wrasses are undelimited type 2 species because testicular tissue(spermatogenesis area) appears in most parts of the gonads during ovary of degenerative stage. Both initial- and terminal-phase males were present in the investigated populations, indicating that Halichoeres poecilopterus, H. tenuispinis, and Ps. sieboldi are of the diandric type. In contrast, Pt. flagellifer is considered a monandric type, because all males in the investigated populations were terminal-phase males produced via sex change from functional females.

• Research in Community and Public Health Nursing
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• v.10 no.1
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• pp.227-238
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• 1999

The goal of this study is to discover the effect of sex education on sex-related knowledge and attitudes of middle school girls. Non-equivalent control group pretest-posttest design was used. The number of experimental group students was 134 and the number of control group students was 134. A total of 268 second grade middle school girls were selected for a convenience sampling method. This study was carried out in a middle school located in Taegu City, Korea, from February 5 to February 18, 1998. To des cover the needs of sex education, the researcher sent a predesigned questionnaire to 1464 girls in 19 different middle schools. The sex education curriculum was designed on the basis of this survey's results. 'The Sex Education Teaching Plan' (published by the Research Institution of Korean School Health Education) and 'Sex and Happiness' (published by the Seoul City Education Ministry) were used to redesign the sex education curriculum and content. Fifty minute long sex education classes were taught to the experimental group every other day and the total number of classes was five. The contents of the teaching -learning plan for sex education were: 'The Characteristics of Adolescence', 'Pregnancy and Contraception', 'Friendship with the Opposite Sex and Prevention of Sexual Violence', 'Prevention of Venereal Disease', and 'Sex and Society'. To measure the degree of sex knowledge of the subjects, the researcher used the modified sex knowledge tools of Kim(l995) and Han(1997). The reliability values of these sex knowledge tools range from 0.71 to 0.74, using Cronbach's alpha. To measure the degree of sex attitude in the subjects, the researcher used the modified sex attitudes tools of Han(l997). The reliability values of these sex attitude tools range from 0.73 to 0.78 using Cronbach's alpha. The PC-SAS package program was used to analyse the data along with Frequency, Percentage, XLtest, t -test, and a paired t -test The results of this study were as follows; 1. The first hypothesis was accepted. The experimental group showed more change in sex - related knowledge than the control group(t =22. 76, p=0.0001). 2. The second hypothesis was accepted. The experimental group showed more change in sex-related attitudes than the control group (t=11.91, p=0.0001). In conclusion, the level of sex-related knowledge and sex-related attitudes of middle school girls who received sex education was higher than that of the girls who did not receive sex education. According to this research, planned sex education was effective in forming accurate knowlege and appropriate attitudes related to sex. Clearly, we must carry out a well-designed step by step sex education program that is well-suited to the sex education needs and the developmental level of the students.

• Animal cells and systems
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• v.13 no.4
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• pp.439-445
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• 2009

Cytochrome P450 aromatase (P450arom) catalyzes the conversion of androgens to estrogens and plays an important role in reproduction and development in vertebrates. We investigated the expression patterns of ovarian P450arom (P450aromA) and brain P450arom (P450aromB) mRNA during sex change in black porgy. Maturity was divided into seven stages from male to female (immature testis, mature testis, testicular portion of mostly testis, ovarian portion of mostly testis, testicular portion of mostly ovary, ovarian portion of mostly ovary, and mature ovary). P450aromA expression was significantly higher in the ovarian portion of mostly-ovarian stage fish, and P450aromB expression was highest in the brain of black porgy with mostly-ovarian gonads. Histology showed that testicular tissues were disintegrated with the development of ovarian tissue associated with an increase in the expression of the two P450arom mRNAs during sex change. Interestingly, among various tissues, P450aromA was only expressed in the ovary, and P450aromB was only expressed in the brain. To understand the role of gonadotropin-releasing hormone (GnRH) and estradiol ($E_2$), we injected exogenous hormone (GnRH analogue [GnRHa] and $E_2$) into immature black porgy. In the GnRHa group, expression of the two P450arom genes decreased 12 h after injection, and expression of the two P450arom genes were significantly higher at 6 dafter $E_2$ injection. These results provide useful baseline knowledge on the mechanism of natural sex change in black porgy.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.1
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• pp.100-111
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• 2004

The purpose of this study is to investigate fashion advertisements portraying ambiguous sex phenomena, including homosexuality codes and to analyze the meaning of these advertisements in order to develop effective fashion advertisements strategies. The method of this study was to observe the readings about ambiguous sex theory, including homosexuality, and analyze fashion advertisements that express this through the Internet and fashion journals. The ambiguous sex expression seen in fashion advertisements meet various consumers' needs which is what the latest advertisement market requires, and offer competitive brand image by fresh appeal. In the background, there are various complex factors like the change of contemporary spirit, and designers' tastes and values about homosexuality. The kinds of ambiguous sex expression techniques portrayed in fashion advertisements can be divided as the ambiguity of physical codes and the ambiguity of sex role identity. These advertisements do play a role as a public campaign for a change in society from the sociocultural point of view. And, from the economical viewpoint, they approach the consumer as a fresh marketing strategy. From the esthetic viewpoint, they express new esthetic sense named “edge” And seen from the designers' viewpoints, they express designers' private sexual identities.