• Korean Journal of Plant Taxonomy
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• v.39 no.2
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• pp.80-85
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• 2009

Three Korean Broussonetia species (Moraceae) were reexamined based on morphological characters. The plants which has been used for making traditional paper Hanji in Korea are considered hybrid species between B. kazinoki and B. papyrifera, its natural habitat was firstly discovered in Is. Gageo (Jeonnam Province). Thus it is newly described as B. ${\times}$ hanjiana M. Kim. Its Korean name is changed into Daknamu instead of Kkujidaknamu. Therefore, Korean name for B. kazinoki is also changed into Aegidaknamu instead of Daknamu. Dioecious plants of Broussonetia kazinoki which were found in Is. Gageo are named as B. kazinoki for. koreana M. Kim (Gageo-Aegidaknamu).

• Journal of Aquaculture
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• v.11 no.4
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• pp.529-546
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• 1998

Gonadal part that developed by indifferentiation period for 6 months after hatching is made as gonad and fat body. These gonad are thin semi-transparant and undistinguished germ cell. Germinal epithelium is distinguished by development of gonad epithelial tissue from 7 months after hatching. Sex differentiation is begun by oogonia develoment at 8 months after hatching. Primary oocytes grow over germinal epithelium of gonadal cavity, at 9 months after hatching, gonadal cavity become ovarian cavity as they increasing. As soon as oocytes at 13 months after hatching are filled with the whole part of gonad, degeneration of oocyte is begun. And then, gonad has cavity tissue, a small number of oocyte are located in gonadal cavity. At 15 months after hatching, new primary oocyte develop and cavity of ovarian tissue in the central of ovarian cavity. Spermatogonia multiplicate and cavity tissue consist of testicular tissue. These gonad become hermaphrodite and then ditermine the sex of female and male. These results show the red sea bream is juvenile hermaphrodite and undif-ferentiated gonochoristic teleost. Male and female differentiation type of gonad is divided in undifferentiation stage, oogonia-like stage, ovary-like stage, ovary development stage, hermaphroditic testis stage, hermaphroditic ovary stage, and testis development stage. Undifferentiation stage is continued total lenth 18cm at 13 months after hatching. ovary-like stage is continued total length 11~18cm at 13 months after hatching. Ovary-like stage is continued total length 14~26cm at 10~14 months after hatching. Ovary development stage begins from total length 20cm, 14 months after hatching. At 20 months after hatching, 44 percent of total sampled individuals had ovary. Hermaphroditic ovary stage first begins total length 19~20 cm at 15 months after hatching, but it is not observed total length 28~29cm at 20months after hatching. Hermaphroditic testis stage first begins total length 21~22cm at 20months after hatching and is continued for 20months. Testis development stage first begins total length 20~21cm at 20 months after hatching, and is occupied 33 percent total length 28~29cm at 20 months. The beginning of sex differentiation more than 50 percent is from total length 16cm at 11 months after hatching. Sex determination begins total length 20cm, 14months after hatching in female and total length 20cm, 15 months after hatching in male. Sex determination more than 50 percent begins total length 23cm,, 17 months after hatching. Undifferentiated gonadal part of red sea bream consist gonad and fat body. As differentiation is going on and gonad is growing, fat body shrinks. This appearence is showed the same tendency in 3-year old red sea bream. 1.9mm larvae after hatching grow about 19mm larvae for 47 days. The relationship between the total length and body weight of larvae and juveniles in $BW=4.45{\times}10^{-6}TL^{3.4718}$ r=0.9820. Fishes in cage culture grow to maximum total length 28.4cm. The relationship between the total length and body weight of these fishes is $BW=2.36{\times}10^{-2}TL^{2.9180}$, r=0.9971. Undifferentiated gonadal part of red sea bream consist gonad and fat body. As differentiation is going on and gonad is growing, fat body shrinks.

• Parasites, Hosts and Diseases
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• v.21 no.1
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• pp.111-117
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• 1983

1979∼1980연 칠월초에 서부 비무장지대 (DMZ)에서 모기 유충채집을 실시한 바 Aedes alboscutellatus의 유충을 제집하여 사육한 결과 성충(♀,♂), 완전유충, 유충 및 편의 탈피각등 분류에 필요한 자료를 얻었다. 이 종은 Reisen등(1971)에 의하여 한국에서 처음 성충(♀)채집을 기록하였으나 이를 확증할 만한 표본이나 분류학적인 기재가 없어 분류상의 오독으로 간주되어 왔었다. 저자등은 본 채집을 통하여 분류상 필요한 모든 자료를 수집하였기에 성충(♀, ♂), 유충, 항, 자충생식기등의 특징을 Reinert(1973)의 기재와 상세히 비교 검토한 결과 웅충에서 gonostylar claw와 basal mesal lobe에 있는 강모의 수가 다르고 자웅충에서는 subspiracular area에 횐 비늘들이 모여있는 점을 발견하였다. 그러나 이들 차이점을 여기에서는 단지 지리적 변화로 간주하였으므로 더 많은 수의 채집을 통하여 보다 확실한 구각이 요구된다 이 표본의 장기보관을 위하여 암수 각 한개섹의 표본과 그에 수반되는 유충 및 편의 탈피곡 표본을 미국 Smithonian연구소에 보냈으며 나머지는 미 8군 예방의무부 곤충연구실에 보관되어 있다.

• The Korean Journal of Malacology
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• v.16 no.1_2
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• pp.35-41
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• 2000

We investigated the gonad index (GI), gonadal development, the reprodutive cycle and first sexual maturity of the venus clam, Cyclina sinensis by histological observation. Samples were collected from the intertidal zone of Komso Bay, Chollabuk-do, west coast of Korea, from April 1998 to March 1999. This clam is dioecious and oviparous. Monthly changes in the gonad index (GI) showed a similar pattern to the reproductive cycle. Ripe oocytes are about 90-100 ㎛ in diameter. The spawning period was between early July to September, and the main spawning occurred between July and August when the sea water temperature was over 20$\^{C}$ The reproductive cycle of this species can be divided into five successive stages: early active stage (February to April), late active stage (March to June), ripe stage (April to August), partially spawned stage (July to October), and spent / inactive stage (September to February). Percentages of first sexual maturity of female and male clams measuring 26.1-30.0 ㎜ in shell length were 53.3% and 62.5%, respectively, and 100% for the clams > 41.0 ㎜. It is assumed that both sexes begin reproduction at about two years age.

• Korean Journal of Microbiology
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• v.43 no.2
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• pp.77-82
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• 2007

In a homothallic ascomycete Aspergillus nidulans, sexual development is inhibited by various environmental stresses such as acetate medium, visible light and high osmolarity conditions. In order to study the genes involved in this stress-related regulatory network, we first attempted to isolate mutants that could develop cleistothecia even in the presence of any of those stresses including intensive visible light. More than 10,000 mutants were screened and 167 mutants were analyzed. Among them, 152 mutants underwent sexual development under the single stress condition of either high osmotic, high acetate or light condition but no sexual development in more than two stresses. Six mutants can produce cleistothecia under light or acetate stress but not in salt stress. Moreover, 6 mutants showed the ability to develop cleistothecia under the light but not under the acetate or osmo-stress. The mutants were revealed to have independent single gene mutation and grouped into different complementation groups (silA-F). The mutant alleles were all recessive to that of wild type. The light responsiveness of development implies the existence of delicate regulation process including reception and translocation of light signaling and determination of development.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.201-210
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• 1998

Sex ratios, and patterns of tree size and growth variation, resource allocation, spatial and age class distribution between the sexes were investigated in natural populations of the sexual trees, R. trichocarpa and R. sylvestris, and the mainly asexual, clonal tree, R. javanica of the dioecious Rhus (Anacardiaceae) distributed in Korea. Sex ratios for three species exhibited a significant degree of female bias, but among the populations, sex ratios were seen to vary quite widely. The measurement of tree size and annual increment of male trees in R. trichocarpa and R. sylvestris were significantly higher than those of female trees, but not significantly different in R. javanica. In all of the species, flowering branch number per individual and inflorescence number per branch of males outnumbered those of females. Branch number per individual, rachis(leaf) number per branch and rachis(leaf) number per inflorescence were more in females than in males. These results were considered as reproductive efforts to increase the pollen supply in males and the fruit production in females. Spatial distribution analysis in two different populations of R. trichocarpa indicated that males and females were randomly distributed in space, but seedlings were clumped around parental trees. Analysis of age class distributions between the sexual reproduction trees, R. triclaocarpa and R. sylvestris, and the asexual, clonal tree, R. javanica showed a different distribution in frequencies of males and females in each age class. These results showed that sexual and asexual reproduction tree species had almost different preference of habitats, and different sex ratio and annual growth.

• Korean Journal of Poultry Science
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• v.19 no.3
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• pp.113-123
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• 1992

This study was carried out to build up new synthetic egg Production lines which had sex linked gene for feather color sexing and had also superior combining ability for producing the best commercial chicks. In order to make autosexing layer line, the commercial layers which had Z$^{s}$ Z$^{s}$ and Z$^{s}$ W were mated. Among progeny, the chicks which had homozygote of silver gene and non-silver gene were selected for making dam and sire lines. Afterwards the closed flock breeding method was utilized to improve general performances of the each line. The performances of egg production in synthetic line were 161 day for age at sexual maturity, 219 eggs for total egg number to 60 weeks of age, 84% for hen-day egg production and 619 for average egg weight. There was no difference in egg production between new synthetic lines and imported breeds. In the analysis of genetic trends, the estimates of genetic parameter in the autosexing lines were similar to those of the general population of layer breeders. This results indicated the consistency of genetic variation from this selection.

• The Korean Journal of Malacology
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• v.19 no.2
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• pp.117-124
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• 2003

Reproductive cycle and sex ratio of the marsh clam Corbicula japonica, a oviparous clam, were investigated monthly by histological observation. Samples were collected in brackish water of Namdae stream on the east coast of Korea from November 2000 to October 2001. It was able to devide the reproductive cycle of this species into five successive stages; early active (April to June), late active (May to June), ripe (June to August), partially spawned (June to September), spent (September to January) and resting stage (February to April). The spawning period was from July to September, and the main spawning occurred between August and September when seawater temperatures reached above 26$^{\circ}C$. Mature eggs of Corbicula japonica were 60-70 ${\mu}m$ in diameter. The sex ratio of individuals over 10.1 mm in shell length was about 1:1 (x$^2$ = 1.22, p > 0.05).

• Computational Structural Engineering
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• v.12 no.1
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• pp.86-94
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• 1999

예비구조설계에서는 구조시스템 대안의 생성과 발전, 여러 방법과 대상에 따른 해석과 설계 다양한 요구조건과 구조적 특성을 고려한 여러 구조시스템 대안의 비교 및 선택 과정을 거친다. 그리고, 이러한 각 과정은 구조설계자의 경험적 지식을 바탕으로 하는 종합적인 사고와 판단에 따라서 단계적, 반복적으로 이루어진다. 그러므로, 예비구조설계에서는 정형화된 자료와 작어뿐 아니라 비정형화된 자료와 작업도 처리해야 한다. 따라서, 컴퓨터는 정형화된 자료와 작업을, 구조설계자는 비정형화된 자료와 작업을 직접 처리하고 이를 상호작용을 통하여 교환 및 지시하는 방식, 즉 구조설계자와 컴퓨터의 역할분담에 기초한 상호작용방식을 통하여 예비구조설계에 컴퓨터를 효율적으로 활용할 수 있을 것이다. 구조설계자와 컴퓨터의 역할분담에 기초한 상호작용을 원활히 지원하기 위해서는 구조시스템 대안의 기하학적 향상, 재료에 대한 자료를 효과적으로 제시할 수 있는 3차원 관점, 각 구조시스템 대안을 검토하고 비교하는 사항이 되는 다양한 요구조건에 대한 자료들을 관리하고 제시할수 있는 요구조건 관점이 필요하다. 그리고 예비 구조설계가 진행되어 온 과정, 방향, 설계의도등의 파악을 위한 바탕이 될 수 있는 작업과정관점, 구조시스템 대안 발전 관점이 필요하다. 예비구조설계의 프로세스 조절을 위한 상호작용을 효과적으로 지원하기 위해서는 컴퓨터가 수행 할 수 있는 정형화된 작업들을 예비구조설계의 진행순서인 구조시스템 대안의 생성과 발전, 구조시스템 대안의 해석과 설계, 구조시스템 대안의 선택에 따라서 나열하여 제시할 필요가 있다. 이를 통해서 구조설계자는 자신의 판단에 따라서 다음에 수행해야 할 작업을 결정하고, 그에 해당하는 정형화된 작업을 컴퓨터가 제시한 작업 중에서 선택하고 그 수행을 지시하여 자신의 경험적 지식과 설계의도에 맞추어 예비구조설계의 프로세스를 조절할 수 있다.정조합력은 유의차가 컸으나, 상반조합 능력은 없었다. 교배친의 우성효과는 컸다. 잡종강세 환경변이 및 상가적 작용도 컸다. 우성의 방향은 정의 방향이었으므로 우성귀전자가 크게 작용하였다. 이들 형질들의 귀전자들은 초우성을 나타내었다. 교배친의 자견층중의 우성순서는 잠120>잠114>잠108>잠119>잠118>잠107>잠117>잠113 순이었고, 웅견층중에서는 잠114>잠108>잠120>잠117>잠118>잠107>잠119>잠119>잠113 순이었다. 자견층 비율에서는 광의의 귀전력이 협의의 귀전력보다 컸고, 웅견층 비율에서는 같았다, 견층 비율에서는 일반조합 능력은 크게 나타났으나, 특정조합 능력과 상반조직 능력은 나타나지 않았다. 자견층 비율에서 교배친의 우성효과는 컸다. 자견층 비율에서는 교배친의 우성효과는 적었다. 자웅견층 비율의 잡종 강세는 적게 나타났다. 환경변이와 상가적 작계는 자웅견층 비율에서는 크게 나타났다. 우성의 방향은 자견층 비율에서는 정의 방향으로 우성 귀전자가 크게 작용하였으며, 자견층 비율에서는 정의 방향으로 우성 귀전자가 부분적으로 작용하였다. 교배친의 자견층 비율의 우성순서는 잠117>잠114>잠108>잠120>잠118>잠119>잠107>잠113 순이었고, 자견층 비율에서는 잠114>잠117>잠108>잠118>잠107>잠119>잠113>잠120의 순이었다.지방산의 조성이 많은 차이를 보였다.{2+}$ 26 및 $Na^+$ 26 mg $L^{-1}$이었다. 양액 재배 후 버려지는 폐양액 중의 무기성분 함량은 양액재배에 이용되는 원수에 비해 상당히 높아졌다.료로서 응용 가능성이 있음을 시사한다.약재료인 약초류 등을 이용하였는데 오랫동안 푹 삶아 그물에 곡류 등을 넣어 죽이나 밥으로 조리하였으며 면으로도 조리하였다. 이상과 같이 조선시대 주식류의 종류 및 조리방법에 대한

• Korean Journal of Plant Taxonomy
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• v.34 no.3
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• pp.245-264
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• 2004

For nine taxa of the genus Carex which consist of C. arenicola, C. chordorhiza, C. curta, C. gibba, C. laevissima, C. leiorhyncha, C. neuromrpa, C. maakii and C. remouscula with mixed pistillate and staminate flowers, morphological characters such as inflorescense, spikelet, inflorescence bract, utricle, pistillate and staminate scales, achene, length between two spikelets were observed to find useful characters for their identification. Especially, the shape and the number of spikelet were very useful characters to divide the treated nine taxa into two groups, the their keys were prepared. The first group was comprised of five species of C. arenicola, C. chordorhiza, C. curta, C. gibba, and C. remouscula, which were characterized by broadly oboval or narrowly elliptical shape of spikelet, and 3-9 spikelets per infIorescence and gradual decrease in length between two spikelets. The second group was composed of four species of C. laevissima, C. leiorhyncha, C. neurocarpa, C. maakii, which were distinguished by oval shape of spikelet, and 17-20 spikelets per infIorescence and repetition of increase.