• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.164-171
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• 2005

Codium fragile (Suringar) Hariot, an edible green alga is farmed in Korea by natural blooming zygotes attachment. Experiments were conducted to reveal the conditions for artificial seed production of C. fragile by sexual and asexual reproduction. Growth was compared between zygotes attachment (sexual reproduction) and isolated utricles with medullary filaments (asexual reproduction). Zygotes and isolated utricles with medullary filaments were cultured under different light conditions (10, 20, 40, 60 and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and temperatures (5, 10, 15, 20 and $25^{\circ}C$) under 16:8LD. Maximum growth of zygote was $261.3{\pm}21.0\;{\mu}m$ under $15^{\circ}C$ and $20\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 13 days culture. Maximum regeneration of isolated medullary filament was $8.1{\pm}1.7\;mm$ per one isolated utricle under $20^{\circ}C$ and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 15 days culture. After intermediate culture during two months in the field, morphogenesis occurred in both sexual and asexual reproduction, and growth of young thalli was not significantly different (p>0.05) between the both reproduction methods. Even though seed production of C. fragile is possible in both sexual and asexual reproduction, the mass artificial seed production of asexual reproduction is much more effective than that of sexual reproduction that is too much affected by maturity.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1576-1584
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• 2008

In this study, canonical correlation analysis (CCA) was applied to estimate the relationship between three different sexual maturity traits (X set: days to first egg (DFE), weight of the first egg (WFE), body weight at first egg (BWFE)) and level of nutrient intake (Y set: energy (EI) and protein intake (PI)) or the egg production traits at two different periods (Z set: number of egg (NE1 and NET) and weight of egg (WE1 and WET) from 22 to 25 (Wfirst) and 22 to 33 wk of age (Wall), respectively), which were measured from 64 egg-type pullets (Isa Brown) manipulated for time of access to energy and protein sources to onset of egg production. Partial CCA (PCCA) was used to eliminate the contribution of differences in the levels of nutrient intake to canonical variables for X and Z sets at the first production period. Estimated canonical correlation coefficients between X set and Y set (0.429, p = 0.042), X set and Z set (0.390, p = 0.007 for Wfirst) and within Z set (between Wfirst and Wall; 0.780, p<0.001), and partial canonical correlation coefficient between X set and Z set (0.415, p = 0.009) were significant. Canonical weights and loadings from CCA indicated that the BWFE had the largest contribution compared to the DFE and WFE to variation of egg number produced at two different periods. The results from PCCA indicated that the contribution of PI and EI to the degree of the correlation between canonical variables for X and Z sets were unfavourable. In conclusion, the effect of body weight at sexual maturity upon the availability of nutrients can have a higher contribution to variation of egg production in pullets if the contribution of differences in nutrient intakes to onset of egg production were eliminated.

• Journal of Ecology and Environment
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• v.31 no.2
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• pp.107-113
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• 2008

We measured a set of 37 morphological characteristics in 97 specimens of adult Korean chub, Zacco koreanus, trapped in the Milyang River, Korea, in May and October of 2005. Twelve out of thirty-seven morphometric measurements were significantly different between the sexes. In particular, both the pectoral fin length and the direct distance between the insertion of the dorsal fin and the insertion of the anal fin were highly significant (p < 0.001). This sexual dimorphism may reflect the outcome of sexual selection in this species.

• Child Health Nursing Research
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• v.8 no.3
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• pp.313-321
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• 2002

We would like to suggest the guideline of use of materials of sexual education for adolescent in school by examining the status of use of materials and by evaluating the video materials frequently used. Survey was done by enquetes on status of use of materials of sexual education from school nurses in 190 primary, 44 middle and 50 high schools in Seoul, Kyonggi-do and Kangwon-do from August 1999 to February 2000. The frequently used 84 videotapes were evaluated on their contents. As for the status of use, 99.3% of subjected schools possessed the materials for sexual education. Decision of purchase was determined according to the review of contents (92.6%). Information about materials was received by the advertisement in newspapers or broadcasting (46.1%) or recommendation of peer teacher (32.4%). Videotape was most frequently used (64.1%) rather than books or CD. Teachers concerns on the materials were the educational content according to developmental stage of students (41.9%), content provoking interest (33.5%) and concrete guide for teacher (10.6%). As for the evaluation of the contents of videotapes, a subject of education was not described out of 46.6%. Videotape producer were mostly the Government-affiliated institutes or non-profit organizations (86.8%). The year of production was indicated from 41.7%. Running time range of 21-30 minutes was highest (55.9%). The price was marked in only one videotape. Subjects of contents were general sexual education (34.5%), sexual violence or sexual harassment (21.4%), pregnancy and contraception (14.2%) and AIDS and sexually transmitted diseases (8.3%) and dating and adolescent change (4. 8%), and etc (11.9 %). According to above results, we suggested that materials for sexual education should be completed with a description on the subjected group, summary of content, information on the tape producer, year of production, running time and sale price.

• The Korean Journal of Ecology
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• v.17 no.4
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• pp.463-469
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• 1994

For better understanding of population dynamics of Symplocarpus renifolius, some aspects of seed production were studied in natural populations for 3 years. The rate of reproducing plants (RP) was 8.06% among the whole studied. The RPs were 0.0% in leaf size class under 500cm2 per individual, and 3.6% in 500~1,000cm2, and 44.3% in over 3,000cm2. The resource allocated to sexual organ was 11.6% of total biomass at the end of growing season, and that to belowground was about 80% regradless of presence or absence of sexual organ. In the previous and the next years of seed production, the energy allocated to sexual organ didn't affect the changes of leaf size, year by year. After flowing season. Especially, a large number of sex organ were degraded in April, a period of pollination and fertilization. The number of seeds per individual was degraded in April, a period of pollination and fertilization. The number of seeds per individual was 13~22 and didn't relate to leaf size. But the weight per seed increased along leaf size per individual. Therefore, in S.renifolius population, large individual produced large seeds rather than many seeds.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.508-524
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• 1999

We would like to identify the current status and the problem of the material for sexual education in Korea by analyzing the contents and the subjects of the materials. The 274 materials were collected from 80 institutes from March 1999 to June 1999. The collected ones were analyzed according to title. year of production. producer. subjects of materials and contents. Also, the materials in the internet was searched. Result were summarized by the descriptive statistics with SPSS/PC as followings: Type of materials were video tape (155), books (70), projection slides (43) and CD-ROM (6); Number of production from each institute were 54 from Planned Parenthood Federation of Korea, 39 from Korea Broadcasting System. 23 from Seoul School Health Center. 22 from Seoul Education and Science Research Institute, 16 from Korea Sexual Violence Relief Center, 13 from Republic of Korean National Redcross. and 10 from Korea Educational Development Institute; Subjects of the materials were middle and high school children (55), teachers (35), primary schoolchildren (17) and adult (14), preschool children (5). One hundred forty eight materials did not indicate the specific subjects; Thirty institutes had been providing the information for sexual education and the counseling. According to the above results. we suggest the followings: The systematic development of materials for sexual education appropriate to the specific subjects should be done: Materials in the CD-ROM and internet homepage should be developed more and more; The evaluation tool should be developed and adapted to the materials for the recommendation of the good materials; Database of the sexual materials should be provided for further development, evaluation and utilization.

• Child Health Nursing Research
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• v.9 no.4
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• pp.408-419
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• 2003

Purpose: This study was done to develop a reliable and appropriate evaluation tool for sexual educational materials and to apply it to video materials for recommendation of excellent materials. Method: The items of the content for evaluation were based on the previous studies on the sexual education and evaluation tools. After testing validity and reliability of tool, final evaluation tool for sexual educational materials was developed. The evaluation tool was applied to 84 video materials and the excellent materials were recommended. Result: The final evaluation tool for sexual educational materials which consisted of two parts was developed. One is the evaluation of basic information which includes 8 items: target population, type of materials, producer, year of production, subject, theme, running time, and guide book. The other is the evaluation of content which includes 36 items related to characteristics of material, purpose, efficiency and scope of content. After applying the tool to 84 video materials, 39 excellent sexual education materials were suggested. Conclusion: The systematic development of materials for sexual education appropriate to the specific subjects should be done. Producers should describe the basic information on the outside of materials. For recommending the excellent materials, the periodical standardized evaluation of sexual educational materials should be done, and the database of the excellent materials should be provided for further utilization.

• Mycobiology
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• v.37 no.4
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• pp.247-250
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• 2009

Twenty-five isolates of Fusarium fujikuroi acquired from rice seeds and rice plants evidencing symptoms of Bakanae disease were evaluated to determine their mating types and characterize the formation of their sexual state. The mating types of the isolates were evaluated via multiplex PCR with the diagnostic primers of the mating-type (MAT) region: GFmat1a, GFmat1b, GFmat2c, and GFmat2d. Among the 25 isolates, 11 were identified as MAT-1 (male), and 14 as MAT-2 (female). Four MAT-1 isolates and three MAT-2 isolates were mated and cultured to evaluate the optimal culture conditions for the production of their sexual states. Among four tested media, 10% V8 juice agar proved optimal for the perithecial production of the isolates. The isolates also generated the largest numbers of perithecia when incubated at 23oC in alternating cycles of 12 hr fluorescent light and NUV fluorescent light and 12 hr darkness.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.236-244
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• 2014

The plant pathogen Fusarium graminearum causes Fusarium head blight in cereal crops and produces mycotoxins that are harmful to animals and humans. For the initiation and spread of disease, asexual and sexual reproduction is required. Therefore, studies on fungal reproduction contribute to the development of new methods to control and maintain the fungal population. Screening a previously generated transcription factor mutant collection, we identified one putative $C_2H_2$ zincfinger transcription factor, pcs1, which is required for both sexual and asexual reproduction. Deleting pcs1 in F. graminearum resulted in a dramatic reduction in conidial production and a complete loss of sexual reproduction. The pathways and gene ontology of pcs1-dependent genes from microarray experiments showed that several G-protein related pathways, oxidase activity, ribosome biogenesis, and RNA binding and processing were highly enriched, suggesting that pcs1 is involved in several different biological processes. Further, overexpression of pcs1 increased conidial production and resulted in earlier maturation of ascospores compared to the wild-type strain. Additionally, the vegetative growth of the overexpression mutants was decreased in nutrient-rich conditions but was not different from the wild-type strain in nutrient-poor conditions. Overall, we discovered that the pcs1 transcription factor positively regulates both conidiation and sexual reproduction and confers nutrient condition-dependent vegetative growth.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.184-188
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• 2001

In a summer study during May to July, involving 12 young Murrah buffalo bulls at forty months of average age, the effects of multiple shower vs single shower body cooling and vitamin A, D and E supplementation on the sexual behaviour, semen quality and freezability were investigated. The animals were divided into two groups (6 animals in each group) and housed in a half-walled shed with proper spacing, the feeding management being identical. The bulls in the control group were given a single shower at 1000 h, whereas the experimental bulls were given four showers at 10,12,14 and 16 h. In addition, the experimental bulls were given vitamin A, D and E injections at fifteen day intervals. The sexual behaviour of bulls was observed in terms of reaction time, sexual aggressiveness and ejaculatory thrust. Semen quality of all the bulls was assessed in terms of volume, mass activity, live-dead sperm and sperm concentration, sperm motility and morphology, and acrosomal abnormality. The sexual behaviour did not vary significantly between the groups, whereas semen quality differed significantly for volume, per cent live sperms, total sperms per ejaculate and total live sperm per ejaculate between groups. It can be concluded that sexual behaviour was not influenced by the thermal comfort treatment coupled with periodic vitamin A, D and E injections. But the treatments improved most of the seminal traits in the experimental group of bulls. However, benefit of treatment was not reflected in the freezability traits of the semen.