• Journal of Life Science
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• v.30 no.3
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• pp.239-249
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• 2020

Persimmon flowers are fruit-bearing female, pollen-bearing male, or hermaphrodite, containing both a pistil and a stamen. Using prominent PCNA persimmons as male parents is very important for breeding programs, as the selection procedure for new cultivars bearing male flowers requires a long time and a large field in a traditional crossbreeding method. To improve breeding efficiency through early selection of male flower-bearing plants at the seedling stage, analysis was performed on 88 major cultivars whose gender expressions are known, using two male flower selection markers recommended by Akagi et al. The OGI locus marker and DISx-AF4S marker results showed that 83 and 72 cultivars, respectively, matched in terms of gender expression and marker analysis. For the OGI locus marker, 890 plants were selected from 2,509 seedlings obtained from crossbreeding with the mother plant "Migamjosang," which was the breeding cultivar. Comparing the gender expression of the flowers and the marker with 1,186 crossbred seedlings, excluding the unfertilized and dead plants, inconsistencies were found in 401 plants (33.8%). For the DISx-AF4S marker, 636 plants were selected from 889 seedlings obtained from 12 cross-combinations. The results of the sex expression and marker analysis were compared to 379 plants, excluding the unfertilized and dead plants, and inconsistencies were found in 247 plants (65.2%). These results indicate that the examined DISx-AF4S and OGI locus markers would not be suitable for utilization in the breeding field.

• Development and Reproduction
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• v.13 no.2
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• pp.115-122
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• 2009

Spermatogenesis and ultrastructural characteristics of sperm of brackish water diploid Corbicula japonica were investigated by electron microscope observations. Based on the cytological studies, the spermatozoon of this species (brackish water diploid) C japonica is approximately 55 ${\mu}m$ in length. The sperm head (about 12 ${\mu}m$ long) is elongated and tapers with a slight curve. Sperm nucleus is about 7.90 ${\mu}m$ long, and the acrosome is about 2.70 ${\mu}m$ long: The morphologies of the sperm nucleus type and the acrosome shape of this species are a long arrow-like type and long cone-like shape, respectively. The sperm head of this species (external fertilization, dioecious and oviparous species) is partially modified from that of the primitive type, as seen in triploid Corbicula species (internal fertilization, hermaphrodite and ovoviparous species), reported by some authors. However, this species produces uniflagellate spermatozoa, unlike freshwater triploid hermaphroditic clams being possessed of partially modified biflagellate spermatozoa. Diploid C japonica is similar to those of other bivalves being possessed of a short midpiece containing four mitochondria surrounding the centrioles. The axoneme of the sperm tail flagellum consists of nine pairs of microtubules at the periphery and a pair at the center. The axoneme of the sperm tail shows a 9+2 structure, and from uniflagellate sperm cross sectioned, in particular, wing-like axonernal lateral fins are observed, as seen in external fertilization fishes.

• Development and Reproduction
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• v.5 no.2
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• pp.137-144
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• 2001

Gametogenesis and gonadal development of the sea squirt Halocythia roretzi, which is two years old were investigated by histological study. The specimens were collected in Guryong-po coastal area Kyoungsangbuk-do, Korea from May 1996 to April 1997. The sea squirt is hermaphrodite and oviparous. The ovary is located in the inner wall of the tunic year-round, but the testis can be distinguished from in June. The ovary is composed of 6∼8 gonoducts at the left side and 8∼10 ones at the right side, the testis consists of the complex gonad having irregular sacular structures. Oogonia in the ovarian sac were 11.7∼15.6 ${\mu}m$ in diameter. The early developing oocytes were 39.6∼47.6 ${\mu}m$ and nucleus 10.0∼25.0 ${\mu}m$ in diameter. Oocytes in the ovarian sacs during vitellogenesis were 158.6∼210.0 ${\mu}m$, and fully ripe oocytes which were to 210.0∼230.9 ${\mu}m$ in diameter had several test cells in the cortical parts showing a characteristic of vertebrate. The testis showed a general spermatogenesis as in the marine animals. The three-year old sea squirt occurred the first spawning between January to February under 10$^{\circ}C$

• The Journal of Art Theory & Practice
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• no.13
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• pp.97-132
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• 2012

1799 Francisco de Goya published Los Caprichos with 80 aquatint etchings. On 6 February he advertised it on the front page of the Diario de Madrid. The long advertisement which began with "a collection of prints of capricious subjects, invented and etched by Don Francisco Goya" informed purpose, themes and methods of this collection of prints. According to this advertisement Goya "has chosen as subjects for his work, from the multitude of follies and mistakes common in every civil society and from the vulgar prejudices and lies authorized by custom, ignorance or self-interest, those that he has thought most fit to provide material for ridicules, and at the same time to exercise the artist's imagination." The text emphasized that the 'author' of this series didn't to want to criticise any individual and to be a copyist. From his phantasy Goya invented many creatures like the anthropic, humanized animals etc.. With Los Caprichos he stood on the threshold to Romanticism. The early researchers of Los Caprichos classified its author, Goya as an enlightened intellectual. The similarity of the themes of the series with the subjects of the Enlightenment, his some enlightened 'friends' and the idea to avoid the prevalent mystification of his life supported this theory. But this trend became revised since the 80's of the last century. This made possible to research Goya's works in new perspective and to see that Goya didn't criticise the Spanish society and his contemporaries. Rather he showed its reality and parodied through creatures which are mixtures of the reality that he observed, and visions that he invented. Characters and scenes in Goya's prints are ambiguous and equivocal. They have the values which are defined by the dualistic metaphysic in Europe as oppositional, like good and evil for example, at the same time. Goya himself also appeared in various types in this series. This ambiguousness, or "polyphony", as Jennis Tomlinson defined, is a symptom of the decay of the belief in the Enlightenment which spreaded in Europe as a result of the attack of Bastille and the French Revolution. Goya's self-portrait in pl. 43 of this series, "El sue$\tilde{n}$o de la razon produce monstruos" shows the complex psychology of him and his contemporaries as well. As the rest etchings after this print show witchcraft and monsters reside in the world in which the reason of the Enlightenment and the through the reason weakened God's rule lost their authority. In this thesis I will examine and analyse how Goya represented in Los Caprichos the nature of man and its society, as complex being in which the 'antagonistic' value couple as good and evil couldn't be divided, but are united.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.39-49
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• 2007

We investigated to understand the differences in the karyotypes and the reproductive characteristics between the diploid clam, Corbicula japonica in the brackish water and the triploid clam, C. fluminea in the freshwater. The number of chromosomes of the diploid C. japonica were 38, which can be grouped into 19 pairs of two homologues. These can be divided into 11 pairs of telocentric, 4 pairs of subtelocentric, 3 pairs of submetacentric and one pair of metacentric chromosomes. C. japonica is oviparous and dioecious. The clam has two pairs of gills, with the inner and outer-demibranchs, however, they do not act mainly as marsupia. External fertilization occurs in the brackish water. The triploid marsh clam, C. fluminea has 54 chromosomes, which can be grouped into 18 sets of three homologues. These 18 sets can be divided into one metacentric group, five submetacentric groups and 12 subtelo- or telocentric groups. C. fluminea is ovoviviparous and functional hermaphrodite. The triploid condition may be closely related to hermaphroditism. This species has the inner-demibranchs acting mainly as marsupia. The depletion of ripe eggs occurred in the inner-demibranchs of the gill during the incubatory periods, and ripe eggs produced in the hermaphroditic follicles in the gonad during the non-incubatory periods. The gonad developmental stages of two marsh clams (C. japonica and C. fluminea) can be divided into five stages: early active stage, late active stage, ripe stage, partially spawned stages, and spent/inactive stage.

• Journal of Sericultural and Entomological Science
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• v.52 no.2
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• pp.147-154
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• 2014

We bred a mulberry cultivar named Palcheong, through local adaptability test, which is under registration as a new cultivar for fruit production. Local adaptability test had been carried out at four places (Suwon, Kongju, Wanju, and Jinju) for seven years from 2007. This is belonging to (Morus Lhou(Ser.) Koidz.) selected among mulberry genetic resources preserved in Suwon. Its sex expression was hermaphrodite, which can be used for the production of seedling for fruit production by artificial crossing as pollen parent Palchung showed lower yielding in fruit productivity by 16% compared to control cultivar 'Chungil (Morus alba L.)' for five years. Although Palchung was higher in sugar content of mulberry fruits, it was bigger than that of 'Chungil'. It is adaptable to every where except the places where cold damage and sclerotic disease happen frequently.

• Development and Reproduction
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• v.9 no.2
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• pp.95-103
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• 2005

Reproductive cycle, gonadosomatic index(GSI), egg diameter composition, first sexual maturity, sexually matured length(50% of first sexual maturity), and sex ratio of Amusium japonicum japonicum, were investigated by histological observations and morphometric data. Samples were collected monthly from the subtidal zone of Sogwipo, Jejudo, Korea, for two years. The sun and moon scallop Amusium japonicum japonicum is dioecious. Monthly variation in the GSI showed similar patterns with the reproductive cycle. Ripe oocytes were about $70{\sim}90\;{\mu}m$ in diameter and had thick egg membranes. The spawning period was from November to January, and the main spawning occurred between November and December when the seawater temperature was relatively low. From monthly changes in egg diameter composition, the spawning period was once a year, although the number of spawning frequencies is assumed to occur more than twice during the spawning season. The reproductive cycle of this species could be divided into five successive stages: early active stage(April to June), late active stage(June to September), ripe stage(October to November), spawning stage(November to January), and spent/resting stage(February to April). First sexual maturities in female and male scallops ranging from 85.1 to 90.0mm in shell length were over 50% and they were 100% for scallops over 90.0mm in shell length. In this population, sexually matured shell lengths(50% of rate of group maturity) in females and males were 86.96 and 86.59mm, respectively. The female to male sex ratio among individuals over 85.1mm in shell length was not significantly different from 1:1($X^2=0.18$, p>0.05). No evidence of hermaphrodite was found in histological sections of any scallop examined.