• Title/Summary/Keyword: Viviparous

Search Result 68, Processing Time 0.032 seconds

Uptake of Polysacchride with Development of Alimentary Tract in Embryo of Ditrema temmincki (Teleostei: Imbiotocidae) (망상어 (Ditrema temmincki) 체내자어의 소화관 발달에 따른 다당류의 흡수)

  • LEE Jung Sick;CHIN Pyung
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.29 no.4
    • /
    • pp.438-449
    • /
    • 1996
  • Development of alimentary tract and nutrient absorption in embryo of the viviparous teleost surfperch, Ditrema temmincki were investigated with histochemical methods. Just after hatching mouth of the embryo was opened, and the end part of alimentary tract was opened in TL 4.0 mm. Mucosal folds in the alimentary tract appeared at posterior region from TL 5.0 mm. In TL 30.0 mm, the alimentary tract of the embryo could be distinguished into pharynx, esophagus, anterior intestine, mid intestine, posterior intestine, rectum and anus. From over TL 50.0 mm, the internal histological patterns of the alimentary tract showed similar structures as seen in the adult. The mucous cells in the pharynx were positively reacted to PAS in TL 7.0 mm. PAS positive goblet cell appeared in the intestine from 25.0 mm, from TL 30.0 mm in the rectum, from TL 40.0 mm in the anus and from 50.0 mm in the esophagus. Yolky materials were absorbed completely in TL 6.0 mm. PAS positive polysaccharide absorptive cells began to appear at the posterior parts of the intestine in TL 7.0 mm and appeared in TL 13.0 mm at the rectum, in TL 15.0 mm at the anterior intestine and in TL 40.0 mm at the anterior part of anus. During the gestation period, nutrient absorptive type of the embryo within the maternal body is a placental analogues type of metrotrophy.

  • PDF

Expression of Cytochrome P450 Aromatase Genes during Sex Differentiation in Korean Rockfish, Sebastes schlegeli (조피볼락, Sebastes schlegeli의 성분화 기간 중 Cytochrome P450 Aromatase 유전자의 발현)

  • Lee, Chan-Hee;Kwon, Joon-Yeong
    • Development and Reproduction
    • /
    • v.11 no.3
    • /
    • pp.195-203
    • /
    • 2007
  • Sex determination and sex differentiation are influenced by genotype in many gonochoristic fish. Cytochrome P450 aromatase (CYP19) is the terminal enzyme in steridogenic pathway that converts androgens into estrogens. In this study, partial fragments of aromatase genes (ovarian aromatase, P450aromA and brain aromatase, P450aromB) were cloned and sequenced in Korean rockfish (Sebastes schlegeli), and gene specific primers were designed based on their sequences. Using these primers, aromatase gene expression during sex differentiation was investigated by RT-PCR. Expression of these aromatase genes were detected both in the head and body parts at 35 dab (days after birth). The number of fish that expressed the aromatase genes decreased at 52 dab, implying down-regulation of these genes. However, these genes were expressed at 59 dab in almost all fish studied here. The expression patterns of both genes are similar throughout the investigated period except for 45 dab where the expression of P450aromB was detected in more fish than that of P450aromA both in the head and body parts. Timing of sex differentiation in this species has been shown to be at around $50{\sim}65$ dab by histological analysis. However, the results from this study suggest that sex differentiation of rockfish may take place $1{\sim}2$ weeks earlier than the period proposed previously. The results also suggest that the mechanism of sex differentiation in viviparous fish may be similar to that in oviparous fish in terms of the importance of aromatase action during the critical period.

  • PDF

Characteristics of bovine pulmonary parasites in Bangladesh

  • Rahman, A. K. M. Anisur;Begum, Nurjahan;Rahman, Md Siddiqur;Song, Hee-Jong
    • Korean Journal of Veterinary Service
    • /
    • v.32 no.1
    • /
    • pp.83-85
    • /
    • 2009
  • In a cross-sectional abattoir survey of bovine pulmonary diseases in Mymensingh, during September 2001 to April 2002, subclinical Dictyocaulus viviparous infection was found in mesoendemic level in Bangladeshi adult zebu cattle. The number of mature lung worms varied from $1{\sim}18$ in individual lungs. One to five mature lung worms were most frequent (74.2%) followed by 6 to 10(19.3%) and $11{\sim}18$ (6.5%). Of the total 123 mature worms collected from 31 lungs, there were 50 (40.7%) male and 73 (59.3%) female worms. The female lungworms (mean length 14.41mm) were significantly (P<0.01) larger than the male lungworms (mean length 11.28mm). The number of hydatid cysts varied from $1{\sim}80$ in individual lungs. One to five ($1{\sim}5$) cysts were recorded most commonly (76.0%) followed by $11{\sim}80$ (20.0%) and $6{\sim}10$ (4%). The size (diameter) of the hydatid cysts ranged from $2{\sim}12cm$. Of the total 203 hydatid cysts collected from 31 lungs 45 (22.2%) cysts were fertile and 158 (77.8%) cyst were sterile.

Molecular Identification and Fine Mapping of a Major Quantitative Trait Locus, OsGPq3 for Seed Low-Temperature Germinability in Rice

  • Nari Kim;Rahmatullah Jan;Jae-Ryoung Park;Saleem Asif;Kyung-Min Kim
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2022.10a
    • /
    • pp.283-283
    • /
    • 2022
  • Abiotic stresses such as high/low temperature, drought, salinity, and submergence directly or indirectly influence the physiological status and molecular mechanisms of rice which badly affect yield. Especially, the low temperature causes harmful influences in the overall process of rice growth such as uneven germination and the establishment of seedlings, which has become one of the main limiting factors affecting rice production in the world. It is of great significance to find the candidate genes controlling low-temperature tolerance during seed germination and study their functions for breeding new rice cultivars with immense low-temperature tolerance during seed germination. In this study, 120 lines of Cheongcheong/Nagdong double haploid population were used for quantitative trait locus analysis of low-temperature germinability. The results showed significant difference in germination under low different temperature conditions. In total, 4 QTLs were detected on chromosome 3, 6, and 8. A total of 41 genes were identified from all the 4 QTLs, among them, 25 genes were selected by gene function annotation and further screened through quantitative real time polymerase chain reaction. Based on gene function annotation and level of expression under low-temperature, our study suggested OsGPq3 gene as a candidate gene controlling viviparous germination, ABA and GA signaling under low-temperature. This study will provide a theoretical basis for marker-assisted breeding.

  • PDF

A Critical Review of Language Typology: for the subjecthood of Korean linguistics (언어유형론의 비판적 고찰 한국어는 교착어, 불어는 굴절어라는 것의 의미를 묻다)

  • 목정수
    • Lingua Humanitatis
    • /
    • v.6
    • /
    • pp.185-211
    • /
    • 2004
  • Korean linguistics or linguistics In Korea has the viviparous limitation that on the one hand, it was influxed from Europe and Japan and on the other hand, these days the American linguistics takes the initiative in Korea. That's why Korean linguistics cannot be free of the problems of 'dependence/independence', 'central/marginal', etc. It calls for two conditions to study the nature of Korean itself and to establish the independence of Korean linguistics in this situation. The first condition is that we should reveal some peculiarities of Korean in itself. The second condition is that we should reveal universals of Korean by comparing it objectively with other languages which are typologically and genealogically different. 1 think the first is important but the latter is more important. To meet the second condition, we analysed the expansion structure of NP in Korean and French, and suggested a new tree-diagram for describing equivalently the NP structure of the two languages. As for VP structure, we suggested some possibilities of comparing the final endings in Korean with personal pronouns in French, and of comparing the prefinal ending 'si' in Korean with the second plural pronoun 'vous', etc. As a result of the comparison of Korean and French, we came to conclusion that Korean is a inflectional agglutinative language while French is a agglutinative inflectional one. In other words, they are same in 'typus', are different in 'topos'. This may be a surprising/unexpected conclusion. But this, we think, can lead us to much closer approach to the nature of the two languages Korean and French.

  • PDF

Distribution and Ecology of Genus Corbicula in the North Kyungsang Province I. Distribution and Classification of Genus Corbicula in the North Kyungsang Province (경상북도 재첩자원 분포 및 생태 조사 1.경상북도산 재첩선(Corbicula) 이매패류)

  • 주문규;변경숙;장명호
    • Journal of Aquaculture
    • /
    • v.11 no.4
    • /
    • pp.581-592
    • /
    • 1998
  • To know on the distribution and ecological characteristics of genus Corbicula field survey made from August 1997 to July 1998 in the North Kyungsang Province. Three species, i.e. Corbicula japonica, C. leand and C. papyracea, were inhabited in the North Kyungsang Provice. C. japonica was dioecious and oviparous species and C. leana and C. papyracea were monoecious and viviparous species.

  • PDF

Changes in Plasma Steroid Hormone Levels and Gonad Development by the Control of Photoperiods and Water Temperatures on Timing of Sexual Maturity of Rockfish (Sebastes schlegeli)

  • Baek Hea-Ja;Park Moo-Eog;Lee Young-Don;Kim Hyung-Bae;Rho Sum
    • Fisheries and Aquatic Sciences
    • /
    • v.7 no.1
    • /
    • pp.16-22
    • /
    • 2004
  • Plasma steroid hormone levels in the viviparous rockfish (Sebastes schlegeli) were examined in relation to gonadal histology under controlled photoperiods and water temperatures. To investigate those effects in S. schlegeli the photoperiod was maintained at 15L:9D in June and then it was gradually decreased to 9L: 15D in October. It was then gradually increased to 12L:12D in January, followed by 14L:I0D in February. The water temperature was $19-20^{\circ}C$ in July. From August to October, it was from $18^{\circ}C\;to\;12^{\circ}C$. Then, it was dropped to a low of $19-11^{\circ}C$ in November to December and then gradually increased to $14-15^{\circ}C$ in February. In females, both plasma $estradiol-l7\beta\;$ (E2) and testosterone (T) levels from August to February showed a similar pattern in both the treatment and the control groups. In the treatment group, the peaks of plasma E2 and T were observed in November, and the peaks were closely correlated to histological observations. Oocytes contained many yolk globules (final vitellogenic oocytes), and oocytes at the migratory nucleus stage increased in size. Plasma levels of progesterone did not change much throughout the experimental period. However, in the control group, the peaks of E2, T, and progesterone were observed in February. These results indicate that the controlled photoperiod and water temperature accelerated sexual maturity, corresponding to the advancement of plasma E2 and T peaks by approximately 3 months. In males, plasma T levels showed a similar pattern from August to October in the treatment and control groups, though levels in the treatment group were higher than those in the control group. From histological observations, the treatment group copulated one month earlier.

Phase of Overhead Flooding Damage during Maturation of Rice (벼 성숙기 침관수 피해양상)

  • Choi Jang-Soo;Ann Deok-Jong;Choi Chung-Don;Lee Seong-Phil;Choi Boo-Sull
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.2 no.4
    • /
    • pp.148-155
    • /
    • 2000
  • The typhoon and flooding injury in rice were investigated both the region of downpour at the middle of August and the region of typhoon 'Yanni' at the late of September, 1998 in Kyongbuk provincial of Korea. More than 10% of rice stem were buried by soil inundation, the heading was delayed and the high node tiller was brought out. Yield components were deteriorated and yield was reduced. As the clay in the muddy water was attached on grains of rice, the yield was greatly reduced by reason of low grain filling ratio and polished rice ratio. The injury of muddy water was less at yellow ripening stage than at early ripening stage. On the other hand, the muddy water injury was reduced by the fungicide 'Benomyl' and 'Daconil' treatments. The degree of lodging according to varieties and ripening stages was not made a great difference, while the lodging was mainly occurred in the early transplanting time. In a week after lodging, viviparous spikes were occurred in almost all varieties, the degree of viviparity was shown highly in order of early maturing, middle maturing and late maturing varieties in the field as well as in laboratory test. The viviperous spikes were greatly occurred in the lodging toward hill space within row than row space because the more grains were touched on the ground.

  • PDF

A Study on the Buddhist Contents in the Bencaoshengyabanji (『본초승아반게(本草乘雅半偈)』의 불교(佛敎) 관련 설명에 대한 고찰)

  • Ahn, Jinhee;Yun, Ki-ryoung;Nan, Jie
    • Journal of Korean Medical classics
    • /
    • v.34 no.4
    • /
    • pp.27-64
    • /
    • 2021
  • Objectives : This paper examined the Buddhist contents within the text, Bencaoshengyabanji(本草乘雅半偈). Methods : Medicinals that were searched through Buddhist vocabulary were examined. Results & Conclusions : Medicinals that quoted the Lengyanjing were related to the Water-Fire interaction, food and medicine, and karma, while those that quoted the Shidian were related to 無上道, 去惡殺蟲, 樞機滑利, and 生生之氣. Those related to the Great Earth of the Four Elements corrected the body's form based on Metal Qi, while those related to the Great Water were connected to the circulation of water dampness. Those related to the Great Fire were deeply related to Yang Qi, and those related to the Great Wind were connected to Wind control. Of the Four Origins, medicinals that were viviparous lowered Qi, while those that were oviparous were related to communicating Shen, treating diseases of the Conception Vessel, and the closing and opening of day and night. Medicinals originating from dampness were related to urination and fluid management, while those of metamorphosis were related to the process of Qi. Those related to emptiness were related to the communication of the Qi system, while those related to 六根六塵 were connected to calming the Shen and strengthening the will, and smoothing the nine orifices. Medicinals related to 圓通 were used for improving eyesight and hearing and controlling the closing and opening. Lu Zhi-yi's analysis of medicinals through the Lengyanjing is original in that it suggested a new perspective other than previous theories on pharmacology which were based on the Yin-Yang and Five Phases and Rising/Lowering/Floating/Sinking theories, but also pedantic and exaggerated. The Bencaoshengyabanji is a unique text on medicinals which analyzed each medicinal under Buddhist influence. However, it also followed the contexts of other previous texts on medicinals, and influenced Zou shu.

Change of Seed Yield, Germination Rate and Hard Seed Rate with Harvest Time in Hairy Vetch (Vicia villosa Roth) (헤어리베치 수확 시기에 따른 종자 수량, 발아율 및 경실종자 비율 변화 양상)

  • Ku, Ja-Hwan;Kim, Min-Tae;Son, Beom-Young;Lee, Jin-Seok;Kim, Jung-Tae;Hwang, Jong-Jin;Baek, Seong-Bum;Moon, Jung-Kyung;Kwon, Young-Up
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.32 no.2
    • /
    • pp.157-164
    • /
    • 2012
  • This experiment was conducted to investigate an optimum harvest time for hairy vetch (HV) seed production. The seeds were harvested at 5 times, 35, 42, 48, 54, and 58 days after flowering (DAF) in 2009 and 2010. In 2011, 3 times of harvest, 39, 49, and 53 DAF were done at Suwon, middle part of Korea. HV plants were harvested and threshed by manually at each time. Seed yield, yield components, germination rate, hard seed rate, and viviparous germination rate were investigated. The highest seed yield represented 54 DAF in 2009, 42 DAF in 2010, and 49 DAF in 2011. When the triticale, HV support plant, comes to early lodging, the time of highest yield was delayed. 1,000-seed weight linearly increased from 35 DAF to 54 DAF. The later harvested seed showed a trend of increasing germination and hard seed ratio. However, viviparous germination had occurred because of in rainy season. In conclusion, it was presumed that an optimum harvest time for safe seed production in HV should be during 42 DAF ~ 54 DAF before the rainy season considering seed yield, 1,000-seed weight and germination.